1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * New command line options
9 This is an alias for the --data-directory option.
11 * GDB supports printing and modifying of variable length automatic arrays
12 as specified in ISO C99.
14 * The ARM simulator now supports instruction level tracing
15 with or without disassembly.
19 GDB now has support for scripting using Guile. Whether this is
20 available is determined at configure time.
21 Guile version 2.0 or greater is required.
22 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
24 * New commands (for set/show, see "New options" below)
28 Invoke CODE by passing it to the Guile interpreter.
32 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
34 info auto-load guile-scripts [regexp]
35 Print the list of automatically loaded Guile scripts.
37 * The source command is now capable of sourcing Guile scripts.
38 This feature is dependent on the debugger being built with Guile support.
42 set print symbol-loading (off|brief|full)
43 show print symbol-loading
44 Control whether to print informational messages when loading symbol
45 information for a file. The default is "full", but when debugging
46 programs with large numbers of shared libraries the amount of output
49 set guile print-stack (none|message|full)
50 show guile print-stack
51 Show a stack trace when an error is encountered in a Guile script.
53 set auto-load guile-scripts (on|off)
54 show auto-load guile-scripts
55 Control auto-loading of Guile script files.
57 maint ada set ignore-descriptive-types (on|off)
58 maint ada show ignore-descriptive-types
59 Control whether the debugger should ignore descriptive types in Ada
60 programs. The default is not to ignore the descriptive types. See
61 the user manual for more details on descriptive types and the intended
64 * New features in the GDB remote stub, GDBserver
66 ** New option --debug-format=option1[,option2,...] allows one to add
67 additional text to each output. At present only timestamps
68 are supported: --debug-format=timestamps.
69 Timestamps can also be turned on with the
70 "monitor set debug-format timestamps" command from GDB.
72 * The 'record instruction-history' command now starts counting instructions
73 at one. This also affects the instruction ranges reported by the
74 'record function-call-history' command when given the /i modifier.
76 * The command 'record function-call-history' supports a new modifier '/c' to
77 indent the function names based on their call stack depth.
78 The fields for the '/i' and '/l' modifier have been reordered.
79 The source line range is now prefixed with 'at'.
80 The instruction range is now prefixed with 'inst'.
81 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
82 "record instruction-history" and "list" commands.
84 * The ranges given as arguments to the 'record function-call-history' and
85 'record instruction-history' commands are now inclusive.
87 * The btrace record target now supports the 'record goto' command.
88 For locations inside the execution trace, the back trace is computed
89 based on the information stored in the execution trace.
91 * The btrace record target supports limited reverse execution and replay.
92 The target does not record data and therefore does not allow reading
95 * The "catch syscall" command now works on s390*-linux* targets.
97 * The "compare-sections" command is no longer specific to target
98 remote. It now works with all targets.
100 * All native targets are now consistently called "native".
101 Consequently, the "target child", "target GNU", "target djgpp",
102 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
103 commands have been replaced with "target native". The QNX/NTO port
104 leaves the "procfs" target in place and adds a "native" target for
105 consistency with other ports. The impact on users should be minimal
106 as these commands previously either throwed an error, or were
107 no-ops. The target's name is visible in the output of the following
108 commands: "help target", "info target", "info files", "maint print
113 qXfer:btrace:read's annex
114 The qXfer:btrace:read packet supports a new annex 'delta' to read
115 branch trace incrementally.
119 ** Valid Python operations on gdb.Value objects representing
120 structs/classes invoke the corresponding overloaded operators if
124 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
126 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
127 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
128 its alias "share", instead.
130 *** Changes in GDB 7.7
132 * Improved support for process record-replay and reverse debugging on
133 arm*-linux* targets. Support for thumb32 and syscall instruction
134 recording has been added.
136 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
138 * GDB now supports Fission DWP file format version 2.
139 http://gcc.gnu.org/wiki/DebugFission
141 * New convenience function "$_isvoid", to check whether an expression
142 is void. A void expression is an expression where the type of the
143 result is "void". For example, some convenience variables may be
144 "void" when evaluated (e.g., "$_exitcode" before the execution of
145 the program being debugged; or an undefined convenience variable).
146 Another example, when calling a function whose return type is
149 * The "maintenance print objfiles" command now takes an optional regexp.
151 * The "catch syscall" command now works on arm*-linux* targets.
153 * GDB now consistently shows "<not saved>" when printing values of
154 registers the debug info indicates have not been saved in the frame
155 and there's nowhere to retrieve them from
156 (callee-saved/call-clobbered registers):
161 (gdb) info registers rax
164 Before, the former would print "<optimized out>", and the latter
165 "*value not available*".
167 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
172 ** Frame filters and frame decorators have been added.
173 ** Temporary breakpoints are now supported.
174 ** Line tables representation has been added.
175 ** New attribute 'parent_type' for gdb.Field objects.
176 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
177 ** New attribute 'name' for gdb.Type objects.
181 Nios II ELF nios2*-*-elf
182 Nios II GNU/Linux nios2*-*-linux
183 Texas Instruments MSP430 msp430*-*-elf
185 * Removed native configurations
187 Support for these a.out NetBSD and OpenBSD obsolete configurations has
188 been removed. ELF variants of these configurations are kept supported.
190 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
191 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
192 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
193 i[34567]86-*-openbsd3.[0-3]
194 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
195 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
196 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
200 Like "catch throw", but catches a re-thrown exception.
202 Renamed from old "maint check-symtabs".
204 Perform consistency checks on symtabs.
206 Expand symtabs matching an optional regexp.
209 Display the details of GDB configure-time options.
211 maint set|show per-command
212 maint set|show per-command space
213 maint set|show per-command time
214 maint set|show per-command symtab
215 Enable display of per-command gdb resource usage.
217 remove-symbol-file FILENAME
218 remove-symbol-file -a ADDRESS
219 Remove a symbol file added via add-symbol-file. The file to remove
220 can be identified by its filename or by an address that lies within
221 the boundaries of this symbol file in memory.
224 info exceptions REGEXP
225 Display the list of Ada exceptions defined in the program being
226 debugged. If provided, only the exceptions whose names match REGEXP
231 set debug symfile off|on
233 Control display of debugging info regarding reading symbol files and
234 symbol tables within those files
236 set print raw frame-arguments
237 show print raw frame-arguments
238 Set/show whether to print frame arguments in raw mode,
239 disregarding any defined pretty-printers.
241 set remote trace-status-packet
242 show remote trace-status-packet
243 Set/show the use of remote protocol qTStatus packet.
247 Control display of debugging messages related to Nios II targets.
251 Control whether target-assisted range stepping is enabled.
253 set startup-with-shell
254 show startup-with-shell
255 Specifies whether Unix child processes are started via a shell or
260 Use the target memory cache for accesses to the code segment. This
261 improves performance of remote debugging (particularly disassembly).
263 * You can now use a literal value 'unlimited' for options that
264 interpret 0 or -1 as meaning "unlimited". E.g., "set
265 trace-buffer-size unlimited" is now an alias for "set
266 trace-buffer-size -1" and "set height unlimited" is now an alias for
269 * The "set debug symtab-create" debugging option of GDB has been changed to
270 accept a verbosity level. 0 means "off", 1 provides basic debugging
271 output, and values of 2 or greater provides more verbose output.
273 * New command-line options
275 Display the details of GDB configure-time options.
277 * The command 'tsave' can now support new option '-ctf' to save trace
278 buffer in Common Trace Format.
280 * Newly installed $prefix/bin/gcore acts as a shell interface for the
283 * GDB now implements the the C++ 'typeid' operator.
285 * The new convenience variable $_exception holds the exception being
286 thrown or caught at an exception-related catchpoint.
288 * The exception-related catchpoints, like "catch throw", now accept a
289 regular expression which can be used to filter exceptions by type.
291 * The new convenience variable $_exitsignal is automatically set to
292 the terminating signal number when the program being debugged dies
293 due to an uncaught signal.
297 ** All MI commands now accept an optional "--language" option.
298 Support for this feature can be verified by using the "-list-features"
299 command, which should contain "language-option".
301 ** The new command -info-gdb-mi-command allows the user to determine
302 whether a GDB/MI command is supported or not.
304 ** The "^error" result record returned when trying to execute an undefined
305 GDB/MI command now provides a variable named "code" whose content is the
306 "undefined-command" error code. Support for this feature can be verified
307 by using the "-list-features" command, which should contain
308 "undefined-command-error-code".
310 ** The -trace-save MI command can optionally save trace buffer in Common
313 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
315 ** The command -data-list-register-values now accepts an optional
316 "--skip-unavailable" option. When used, only the available registers
319 ** The new command -trace-frame-collected dumps collected variables,
320 computed expressions, tvars, memory and registers in a traceframe.
322 ** The commands -stack-list-locals, -stack-list-arguments and
323 -stack-list-variables now accept an option "--skip-unavailable".
324 When used, only the available locals or arguments are displayed.
326 ** The -exec-run command now accepts an optional "--start" option.
327 When used, the command follows the same semantics as the "start"
328 command, stopping the program's execution at the start of its
329 main subprogram. Support for this feature can be verified using
330 the "-list-features" command, which should contain
331 "exec-run-start-option".
333 ** The new commands -catch-assert and -catch-exceptions insert
334 catchpoints stopping the program when Ada exceptions are raised.
336 ** The new command -info-ada-exceptions provides the equivalent of
337 the new "info exceptions" command.
339 * New system-wide configuration scripts
340 A GDB installation now provides scripts suitable for use as system-wide
341 configuration scripts for the following systems:
345 * GDB now supports target-assigned range stepping with remote targets.
346 This improves the performance of stepping source lines by reducing
347 the number of control packets from/to GDB. See "New remote packets"
350 * GDB now understands the element 'tvar' in the XML traceframe info.
351 It has the id of the collected trace state variables.
353 * On S/390 targets that provide the transactional-execution feature,
354 the program interruption transaction diagnostic block (TDB) is now
355 represented as a number of additional "registers" in GDB.
361 The vCont packet supports a new 'r' action, that tells the remote
362 stub to step through an address range itself, without GDB
363 involvemement at each single-step.
365 qXfer:libraries-svr4:read's annex
366 The previously unused annex of the qXfer:libraries-svr4:read packet
367 is now used to support passing an argument list. The remote stub
368 reports support for this argument list to GDB's qSupported query.
369 The defined arguments are "start" and "prev", used to reduce work
370 necessary for library list updating, resulting in significant
373 * New features in the GDB remote stub, GDBserver
375 ** GDBserver now supports target-assisted range stepping. Currently
376 enabled on x86/x86_64 GNU/Linux targets.
378 ** GDBserver now adds element 'tvar' in the XML in the reply to
379 'qXfer:traceframe-info:read'. It has the id of the collected
380 trace state variables.
382 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
385 * New 'z' formatter for printing and examining memory, this displays the
386 value as hexadecimal zero padded on the left to the size of the type.
388 * GDB can now use Windows x64 unwinding data.
390 * The "set remotebaud" command has been replaced by "set serial baud".
391 Similarly, "show remotebaud" has been replaced by "show serial baud".
392 The "set remotebaud" and "show remotebaud" commands are still available
393 to provide backward compatibility with older versions of GDB.
395 *** Changes in GDB 7.6
397 * Target record has been renamed to record-full.
398 Record/replay is now enabled with the "record full" command.
399 This also affects settings that are associated with full record/replay
400 that have been moved from "set/show record" to "set/show record full":
402 set|show record full insn-number-max
403 set|show record full stop-at-limit
404 set|show record full memory-query
406 * A new record target "record-btrace" has been added. The new target
407 uses hardware support to record the control-flow of a process. It
408 does not support replaying the execution, but it implements the
409 below new commands for investigating the recorded execution log.
410 This new recording method can be enabled using:
414 The "record-btrace" target is only available on Intel Atom processors
415 and requires a Linux kernel 2.6.32 or later.
417 * Two new commands have been added for record/replay to give information
418 about the recorded execution without having to replay the execution.
419 The commands are only supported by "record btrace".
421 record instruction-history prints the execution history at
422 instruction granularity
424 record function-call-history prints the execution history at
427 * New native configurations
429 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
430 FreeBSD/powerpc powerpc*-*-freebsd
431 x86_64/Cygwin x86_64-*-cygwin*
432 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
436 ARM AArch64 aarch64*-*-elf
437 ARM AArch64 GNU/Linux aarch64*-*-linux
438 Lynx 178 PowerPC powerpc-*-lynx*178
439 x86_64/Cygwin x86_64-*-cygwin*
440 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
442 * If the configured location of system.gdbinit file (as given by the
443 --with-system-gdbinit option at configure time) is in the
444 data-directory (as specified by --with-gdb-datadir at configure
445 time) or in one of its subdirectories, then GDB will look for the
446 system-wide init file in the directory specified by the
447 --data-directory command-line option.
449 * New command line options:
451 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
452 other initialization files, unlike -nx which disables all of them.
454 * Removed command line options
456 -epoch This was used by the gdb mode in Epoch, an ancient fork of
459 * The 'ptype' and 'whatis' commands now accept an argument to control
462 * 'info proc' now works on some core files.
466 ** Vectors can be created with gdb.Type.vector.
468 ** Python's atexit.register now works in GDB.
470 ** Types can be pretty-printed via a Python API.
472 ** Python 3 is now supported (in addition to Python 2.4 or later)
474 ** New class gdb.Architecture exposes GDB's internal representation
475 of architecture in the Python API.
477 ** New method Frame.architecture returns the gdb.Architecture object
478 corresponding to the frame's architecture.
480 * New Python-based convenience functions:
482 ** $_memeq(buf1, buf2, length)
483 ** $_streq(str1, str2)
485 ** $_regex(str, regex)
487 * The 'cd' command now defaults to using '~' (the home directory) if not
490 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
491 default for GCC since November 2000.
493 * The command 'forward-search' can now be abbreviated as 'fo'.
495 * The command 'info tracepoints' can now display 'installed on target'
496 or 'not installed on target' for each non-pending location of tracepoint.
498 * New configure options
500 --enable-libmcheck/--disable-libmcheck
501 By default, development versions are built with -lmcheck on hosts
502 that support it, in order to help track memory corruption issues.
503 Release versions, on the other hand, are built without -lmcheck
504 by default. The --enable-libmcheck/--disable-libmcheck configure
505 options allow the user to override that default.
506 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
507 This configure option allows the user to build GDB with
508 libbabeltrace using which GDB can read Common Trace Format data.
510 * New commands (for set/show, see "New options" below)
513 Catch signals. This is similar to "handle", but allows commands and
514 conditions to be attached.
517 List the BFDs known to GDB.
519 python-interactive [command]
521 Start a Python interactive prompt, or evaluate the optional command
522 and print the result of expressions.
525 "py" is a new alias for "python".
527 enable type-printer [name]...
528 disable type-printer [name]...
529 Enable or disable type printers.
533 ** For the Renesas Super-H architecture, the "regs" command has been removed
534 (has been deprecated in GDB 7.5), and "info all-registers" should be used
539 set print type methods (on|off)
540 show print type methods
541 Control whether method declarations are displayed by "ptype".
542 The default is to show them.
544 set print type typedefs (on|off)
545 show print type typedefs
546 Control whether typedef definitions are displayed by "ptype".
547 The default is to show them.
549 set filename-display basename|relative|absolute
550 show filename-display
551 Control the way in which filenames is displayed.
552 The default is "relative", which preserves previous behavior.
554 set trace-buffer-size
555 show trace-buffer-size
556 Request target to change the size of trace buffer.
558 set remote trace-buffer-size-packet auto|on|off
559 show remote trace-buffer-size-packet
560 Control the use of the remote protocol `QTBuffer:size' packet.
564 Control display of debugging messages related to ARM AArch64.
567 set debug coff-pe-read
568 show debug coff-pe-read
569 Control display of debugging messages related to reading of COFF/PE
574 Control display of debugging messages related to Mach-O symbols
577 set debug notification
578 show debug notification
579 Control display of debugging info for async remote notification.
583 ** Command parameter changes are now notified using new async record
584 "=cmd-param-changed".
585 ** Trace frame changes caused by command "tfind" are now notified using
586 new async record "=traceframe-changed".
587 ** The creation, deletion and modification of trace state variables
588 are now notified using new async records "=tsv-created",
589 "=tsv-deleted" and "=tsv-modified".
590 ** The start and stop of process record are now notified using new
591 async record "=record-started" and "=record-stopped".
592 ** Memory changes are now notified using new async record
594 ** The data-disassemble command response will include a "fullname" field
595 containing the absolute file name when source has been requested.
596 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
597 command, to allow pattern filling of memory areas.
598 ** New commands "-catch-load"/"-catch-unload" added for intercepting
599 library load/unload events.
600 ** The response to breakpoint commands and breakpoint async records
601 includes an "installed" field containing a boolean state about each
602 non-pending tracepoint location is whether installed on target or not.
603 ** Output of the "-trace-status" command includes a "trace-file" field
604 containing the name of the trace file being examined. This field is
605 optional, and only present when examining a trace file.
606 ** The "fullname" field is now always present along with the "file" field,
607 even if the file cannot be found by GDB.
609 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
610 You must have the LZMA library available when configuring GDB for this
611 feature to be enabled. For more information, see:
612 http://fedoraproject.org/wiki/Features/MiniDebugInfo
617 Set the size of trace buffer. The remote stub reports support for this
618 packet to gdb's qSupported query.
621 Enable Branch Trace Store (BTS)-based branch tracing for the current
622 thread. The remote stub reports support for this packet to gdb's
626 Disable branch tracing for the current thread. The remote stub reports
627 support for this packet to gdb's qSupported query.
630 Read the traced branches for the current thread. The remote stub
631 reports support for this packet to gdb's qSupported query.
633 *** Changes in GDB 7.5
635 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
636 for more x32 ABI info.
638 * GDB now supports access to MIPS DSP registers on Linux targets.
640 * GDB now supports debugging microMIPS binaries.
642 * The "info os" command on GNU/Linux can now display information on
643 several new classes of objects managed by the operating system:
644 "info os procgroups" lists process groups
645 "info os files" lists file descriptors
646 "info os sockets" lists internet-domain sockets
647 "info os shm" lists shared-memory regions
648 "info os semaphores" lists semaphores
649 "info os msg" lists message queues
650 "info os modules" lists loaded kernel modules
652 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
653 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
654 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
655 options and inspect the probe arguments using the new $_probe_arg family
656 of convenience variables. You can obtain more information about SystemTap
657 in <http://sourceware.org/systemtap/>.
659 * GDB now supports reversible debugging on ARM, it allows you to
660 debug basic ARM and THUMB instructions, and provides
661 record/replay support.
663 * The option "symbol-reloading" has been deleted as it is no longer used.
667 ** GDB commands implemented in Python can now be put in command class
670 ** The "maint set python print-stack on|off" is now deleted.
672 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
673 apply "flag enum"-style pretty-printing to any enum.
675 ** gdb.lookup_symbol can now work when there is no current frame.
677 ** gdb.Symbol now has a 'line' attribute, holding the line number in
678 the source at which the symbol was defined.
680 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
681 method 'value'. The former indicates whether the symbol needs a
682 frame in order to compute its value, and the latter computes the
685 ** A new method 'referenced_value' on gdb.Value objects which can
686 dereference pointer as well as C++ reference values.
688 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
689 which return the global and static blocks (as gdb.Block objects),
690 of the underlying symbol table, respectively.
692 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
693 object associated with a PC value.
695 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
696 of the address range occupied by code for the current source line.
698 * Go language support.
699 GDB now supports debugging programs written in the Go programming
702 * GDBserver now supports stdio connections.
703 E.g. (gdb) target remote | ssh myhost gdbserver - hello
705 * The binary "gdbtui" can no longer be built or installed.
706 Use "gdb -tui" instead.
708 * GDB will now print "flag" enums specially. A flag enum is one where
709 all the enumerator values have no bits in common when pairwise
710 "and"ed. When printing a value whose type is a flag enum, GDB will
711 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
712 (gdb) print (enum E) 3
715 * The filename part of a linespec will now match trailing components
716 of a source file name. For example, "break gcc/expr.c:1000" will
717 now set a breakpoint in build/gcc/expr.c, but not
720 * The "info proc" and "generate-core-file" commands will now also
721 work on remote targets connected to GDBserver on Linux.
723 * The command "info catch" has been removed. It has been disabled
726 * The "catch exception" and "catch assert" commands now accept
727 a condition at the end of the command, much like the "break"
728 command does. For instance:
730 (gdb) catch exception Constraint_Error if Barrier = True
732 Previously, it was possible to add a condition to such catchpoints,
733 but it had to be done as a second step, after the catchpoint had been
734 created, using the "condition" command.
736 * The "info static-tracepoint-marker" command will now also work on
737 native Linux targets with in-process agent.
739 * GDB can now set breakpoints on inlined functions.
741 * The .gdb_index section has been updated to include symbols for
742 inlined functions. GDB will ignore older .gdb_index sections by
743 default, which could cause symbol files to be loaded more slowly
744 until their .gdb_index sections can be recreated. The new command
745 "set use-deprecated-index-sections on" will cause GDB to use any older
746 .gdb_index sections it finds. This will restore performance, but the
747 ability to set breakpoints on inlined functions will be lost in symbol
748 files with older .gdb_index sections.
750 The .gdb_index section has also been updated to record more information
751 about each symbol. This speeds up the "info variables", "info functions"
752 and "info types" commands when used with programs having the .gdb_index
753 section, as well as speeding up debugging with shared libraries using
754 the .gdb_index section.
756 * Ada support for GDB/MI Variable Objects has been added.
758 * GDB can now support 'breakpoint always-inserted mode' in 'record'
763 ** New command -info-os is the MI equivalent of "info os".
765 ** Output logs ("set logging" and related) now include MI output.
769 ** "set use-deprecated-index-sections on|off"
770 "show use-deprecated-index-sections on|off"
771 Controls the use of deprecated .gdb_index sections.
773 ** "catch load" and "catch unload" can be used to stop when a shared
774 library is loaded or unloaded, respectively.
776 ** "enable count" can be used to auto-disable a breakpoint after
779 ** "info vtbl" can be used to show the virtual method tables for
780 C++ and Java objects.
782 ** "explore" and its sub commands "explore value" and "explore type"
783 can be used to recursively explore values and types of
784 expressions. These commands are available only if GDB is
785 configured with '--with-python'.
787 ** "info auto-load" shows status of all kinds of auto-loaded files,
788 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
789 sequences of commands files, "info auto-load python-scripts"
790 shows status of auto-loading Python script files,
791 "info auto-load local-gdbinit" shows status of loading init file
792 (.gdbinit) from current directory and "info auto-load libthread-db" shows
793 status of inferior specific thread debugging shared library loading.
795 ** "info auto-load-scripts", "set auto-load-scripts on|off"
796 and "show auto-load-scripts" commands have been deprecated, use their
797 "info auto-load python-scripts", "set auto-load python-scripts on|off"
798 and "show auto-load python-scripts" counterparts instead.
800 ** "dprintf location,format,args..." creates a dynamic printf, which
801 is basically a breakpoint that does a printf and immediately
802 resumes your program's execution, so it is like a printf that you
803 can insert dynamically at runtime instead of at compiletime.
805 ** "set print symbol"
807 Controls whether GDB attempts to display the symbol, if any,
808 corresponding to addresses it prints. This defaults to "on", but
809 you can set it to "off" to restore GDB's previous behavior.
811 * Deprecated commands
813 ** For the Renesas Super-H architecture, the "regs" command has been
814 deprecated, and "info all-registers" should be used instead.
818 Renesas RL78 rl78-*-elf
819 HP OpenVMS ia64 ia64-hp-openvms*
821 * GDBserver supports evaluation of breakpoint conditions. When
822 support is advertised by GDBserver, GDB may be told to send the
823 breakpoint conditions in bytecode form to GDBserver. GDBserver
824 will only report the breakpoint trigger to GDB when its condition
830 show mips compression
831 Select the compressed ISA encoding used in functions that have no symbol
832 information available. The encoding can be set to either of:
835 and is updated automatically from ELF file flags if available.
837 set breakpoint condition-evaluation
838 show breakpoint condition-evaluation
839 Control whether breakpoint conditions are evaluated by GDB ("host") or by
840 GDBserver ("target"). Default option "auto" chooses the most efficient
842 This option can improve debugger efficiency depending on the speed of the
846 Disable auto-loading globally.
849 Show auto-loading setting of all kinds of auto-loaded files.
851 set auto-load gdb-scripts on|off
852 show auto-load gdb-scripts
853 Control auto-loading of GDB canned sequences of commands files.
855 set auto-load python-scripts on|off
856 show auto-load python-scripts
857 Control auto-loading of Python script files.
859 set auto-load local-gdbinit on|off
860 show auto-load local-gdbinit
861 Control loading of init file (.gdbinit) from current directory.
863 set auto-load libthread-db on|off
864 show auto-load libthread-db
865 Control auto-loading of inferior specific thread debugging shared library.
867 set auto-load scripts-directory <dir1>[:<dir2>...]
868 show auto-load scripts-directory
869 Set a list of directories from which to load auto-loaded scripts.
870 Automatically loaded Python scripts and GDB scripts are located in one
871 of the directories listed by this option.
872 The delimiter (':' above) may differ according to the host platform.
874 set auto-load safe-path <dir1>[:<dir2>...]
875 show auto-load safe-path
876 Set a list of directories from which it is safe to auto-load files.
877 The delimiter (':' above) may differ according to the host platform.
879 set debug auto-load on|off
881 Control display of debugging info for auto-loading the files above.
883 set dprintf-style gdb|call|agent
885 Control the way in which a dynamic printf is performed; "gdb"
886 requests a GDB printf command, while "call" causes dprintf to call a
887 function in the inferior. "agent" requests that the target agent
888 (such as GDBserver) do the printing.
890 set dprintf-function <expr>
891 show dprintf-function
892 set dprintf-channel <expr>
894 Set the function and optional first argument to the call when using
895 the "call" style of dynamic printf.
897 set disconnected-dprintf on|off
898 show disconnected-dprintf
899 Control whether agent-style dynamic printfs continue to be in effect
900 after GDB disconnects.
902 * New configure options
905 Configure default value for the 'set auto-load scripts-directory'
906 setting above. It defaults to '$debugdir:$datadir/auto-load',
907 $debugdir representing global debugging info directories (available
908 via 'show debug-file-directory') and $datadir representing GDB's data
909 directory (available via 'show data-directory').
911 --with-auto-load-safe-path
912 Configure default value for the 'set auto-load safe-path' setting
913 above. It defaults to the --with-auto-load-dir setting.
915 --without-auto-load-safe-path
916 Set 'set auto-load safe-path' to '/', effectively disabling this
921 z0/z1 conditional breakpoints extension
923 The z0/z1 breakpoint insertion packets have been extended to carry
924 a list of conditional expressions over to the remote stub depending on the
925 condition evaluation mode. The use of this extension can be controlled
926 via the "set remote conditional-breakpoints-packet" command.
930 Specify the signals which the remote stub may pass to the debugged
931 program without GDB involvement.
933 * New command line options
935 --init-command=FILE, -ix Like --command, -x but execute it
936 before loading inferior.
937 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
938 execute it before loading inferior.
940 *** Changes in GDB 7.4
942 * GDB now handles ambiguous linespecs more consistently; the existing
943 FILE:LINE support has been expanded to other types of linespecs. A
944 breakpoint will now be set on all matching locations in all
945 inferiors, and locations will be added or removed according to
948 * GDB now allows you to skip uninteresting functions and files when
949 stepping with the "skip function" and "skip file" commands.
951 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
952 and "show remote hardware-watchpoint-length-limit". These allows to
953 set or show the maximum length limit (in bytes) of a remote
954 target hardware watchpoint.
956 This allows e.g. to use "unlimited" hardware watchpoints with the
957 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
958 watchpoints are slower than real hardware watchpoints but are
959 significantly faster than gdb software watchpoints.
963 ** The register_pretty_printer function in module gdb.printing now takes
964 an optional `replace' argument. If True, the new printer replaces any
967 ** The "maint set python print-stack on|off" command has been
968 deprecated and will be deleted in GDB 7.5.
969 A new command: "set python print-stack none|full|message" has
970 replaced it. Additionally, the default for "print-stack" is
971 now "message", which just prints the error message without
974 ** A prompt substitution hook (prompt_hook) is now available to the
977 ** A new Python module, gdb.prompt has been added to the GDB Python
978 modules library. This module provides functionality for
979 escape sequences in prompts (used by set/show
980 extended-prompt). These escape sequences are replaced by their
983 ** Python commands and convenience-functions located in
984 'data-directory'/python/gdb/command and
985 'data-directory'/python/gdb/function are now automatically loaded
988 ** Blocks now provide four new attributes. global_block and
989 static_block will return the global and static blocks
990 respectively. is_static and is_global are boolean attributes
991 that indicate if the block is one of those two types.
993 ** Symbols now provide the "type" attribute, the type of the symbol.
995 ** The "gdb.breakpoint" function has been deprecated in favor of
998 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
999 of a function. This class is based on the "finish" command
1000 available in the CLI.
1002 ** Type objects for struct and union types now allow access to
1003 the fields using standard Python dictionary (mapping) methods.
1004 For example, "some_type['myfield']" now works, as does
1005 "some_type.items()".
1007 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1010 ** A new function, "deep_items" has been added to the gdb.types
1011 module in the GDB Python modules library. This function returns
1012 an iterator over the fields of a struct or union type. Unlike
1013 the standard Python "iteritems" method, it will recursively traverse
1014 any anonymous fields.
1018 ** "*stopped" events can report several new "reason"s, such as
1021 ** Breakpoint changes are now notified using new async records, like
1022 "=breakpoint-modified".
1024 ** New command -ada-task-info.
1026 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1027 $sdir specifies the default system locations of shared libraries.
1028 $pdir specifies the directory where the libpthread used by the application
1031 GDB no longer looks in $sdir and $pdir after it has searched the directories
1032 mentioned in libthread-db-search-path. If you want to search those
1033 directories, they must be specified in libthread-db-search-path.
1034 The default value of libthread-db-search-path on GNU/Linux and Solaris
1035 systems is now "$sdir:$pdir".
1037 $pdir is not supported by gdbserver, it is currently ignored.
1038 $sdir is supported by gdbserver.
1040 * New configure option --with-iconv-bin.
1041 When using the internationalization support like the one in the GNU C
1042 library, GDB will invoke the "iconv" program to get a list of supported
1043 character sets. If this program lives in a non-standard location, one can
1044 use this option to specify where to find it.
1046 * When natively debugging programs on PowerPC BookE processors running
1047 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1048 watchpoints, which specify a mask in addition to an address to watch.
1049 The mask specifies that some bits of an address (the bits which are
1050 reset in the mask) should be ignored when matching the address accessed
1051 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1052 section in the user manual for more details.
1054 * The new option --once causes GDBserver to stop listening for connections once
1055 the first connection is made. The listening port used by GDBserver will
1056 become available after that.
1058 * New commands "info macros" and "alias" have been added.
1060 * New function parameters suffix @entry specifies value of function parameter
1061 at the time the function got called. Entry values are available only since
1067 "!" is now an alias of the "shell" command.
1068 Note that no space is needed between "!" and SHELL COMMAND.
1072 watch EXPRESSION mask MASK_VALUE
1073 The watch command now supports the mask argument which allows creation
1074 of masked watchpoints, if the current architecture supports this feature.
1076 info auto-load-scripts [REGEXP]
1077 This command was formerly named "maintenance print section-scripts".
1078 It is now generally useful and is no longer a maintenance-only command.
1080 info macro [-all] [--] MACRO
1081 The info macro command has new options `-all' and `--'. The first for
1082 printing all definitions of a macro. The second for explicitly specifying
1083 the end of arguments and the beginning of the macro name in case the macro
1084 name starts with a hyphen.
1086 collect[/s] EXPRESSIONS
1087 The tracepoint collect command now takes an optional modifier "/s"
1088 that directs it to dereference pointer-to-character types and
1089 collect the bytes of memory up to a zero byte. The behavior is
1090 similar to what you see when you use the regular print command on a
1091 string. An optional integer following the "/s" sets a bound on the
1092 number of bytes that will be collected.
1095 The trace start command now interprets any supplied arguments as a
1096 note to be recorded with the trace run, with an effect similar to
1097 setting the variable trace-notes.
1100 The trace stop command now interprets any arguments as a note to be
1101 mentioned along with the tstatus report that the trace was stopped
1102 with a command. The effect is similar to setting the variable
1105 * Tracepoints can now be enabled and disabled at any time after a trace
1106 experiment has been started using the standard "enable" and "disable"
1107 commands. It is now possible to start a trace experiment with no enabled
1108 tracepoints; GDB will display a warning, but will allow the experiment to
1109 begin, assuming that tracepoints will be enabled as needed while the trace
1112 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1113 locations with 4-byte instructions, when they were previously
1114 limited to locations with instructions of 5 bytes or longer.
1118 set debug dwarf2-read
1119 show debug dwarf2-read
1120 Turns on or off display of debugging messages related to reading
1121 DWARF debug info. The default is off.
1123 set debug symtab-create
1124 show debug symtab-create
1125 Turns on or off display of debugging messages related to symbol table
1126 creation. The default is off.
1129 show extended-prompt
1130 Set the GDB prompt, and allow escape sequences to be inserted to
1131 display miscellaneous information (see 'help set extended-prompt'
1132 for the list of sequences). This prompt (and any information
1133 accessed through the escape sequences) is updated every time the
1134 prompt is displayed.
1136 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1137 show print entry-values
1138 Set printing of frame argument values at function entry. In some cases
1139 GDB can determine the value of function argument which was passed by the
1140 function caller, even if the value was modified inside the called function.
1142 set debug entry-values
1143 show debug entry-values
1144 Control display of debugging info for determining frame argument values at
1145 function entry and virtual tail call frames.
1147 set basenames-may-differ
1148 show basenames-may-differ
1149 Set whether a source file may have multiple base names.
1150 (A "base name" is the name of a file with the directory part removed.
1151 Example: The base name of "/home/user/hello.c" is "hello.c".)
1152 If set, GDB will canonicalize file names (e.g., expand symlinks)
1153 before comparing them. Canonicalization is an expensive operation,
1154 but it allows the same file be known by more than one base name.
1155 If not set (the default), all source files are assumed to have just
1156 one base name, and gdb will do file name comparisons more efficiently.
1162 Set a user name and notes for the current and any future trace runs.
1163 This is useful for long-running and/or disconnected traces, to
1164 inform others (or yourself) as to who is running the trace, supply
1165 contact information, or otherwise explain what is going on.
1167 set trace-stop-notes
1168 show trace-stop-notes
1169 Set a note attached to the trace run, that is displayed when the
1170 trace has been stopped by a tstop command. This is useful for
1171 instance as an explanation, if you are stopping a trace run that was
1172 started by someone else.
1174 * New remote packets
1178 Dynamically enable a tracepoint in a started trace experiment.
1182 Dynamically disable a tracepoint in a started trace experiment.
1186 Set the user and notes of the trace run.
1190 Query the current status of a tracepoint.
1194 Query the minimum length of instruction at which a fast tracepoint may
1197 * Dcache size (number of lines) and line-size are now runtime-configurable
1198 via "set dcache line" and "set dcache line-size" commands.
1202 Texas Instruments TMS320C6x tic6x-*-*
1206 Renesas RL78 rl78-*-elf
1208 *** Changes in GDB 7.3.1
1210 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1212 *** Changes in GDB 7.3
1214 * GDB has a new command: "thread find [REGEXP]".
1215 It finds the thread id whose name, target id, or thread extra info
1216 matches the given regular expression.
1218 * The "catch syscall" command now works on mips*-linux* targets.
1220 * The -data-disassemble MI command now supports modes 2 and 3 for
1221 dumping the instruction opcodes.
1223 * New command line options
1225 -data-directory DIR Specify DIR as the "data-directory".
1226 This is mostly for testing purposes.
1228 * The "maint set python auto-load on|off" command has been renamed to
1229 "set auto-load-scripts on|off".
1231 * GDB has a new command: "set directories".
1232 It is like the "dir" command except that it replaces the
1233 source path list instead of augmenting it.
1235 * GDB now understands thread names.
1237 On GNU/Linux, "info threads" will display the thread name as set by
1238 prctl or pthread_setname_np.
1240 There is also a new command, "thread name", which can be used to
1241 assign a name internally for GDB to display.
1244 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1245 has been integrated into GDB.
1249 ** The function gdb.Write now accepts an optional keyword 'stream'.
1250 This keyword, when provided, will direct the output to either
1251 stdout, stderr, or GDB's logging output.
1253 ** Parameters can now be be sub-classed in Python, and in particular
1254 you may implement the get_set_doc and get_show_doc functions.
1255 This improves how Parameter set/show documentation is processed
1256 and allows for more dynamic content.
1258 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1259 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1260 have an is_valid method.
1262 ** Breakpoints can now be sub-classed in Python, and in particular
1263 you may implement a 'stop' function that is executed each time
1264 the inferior reaches that breakpoint.
1266 ** New function gdb.lookup_global_symbol looks up a global symbol.
1268 ** GDB values in Python are now callable if the value represents a
1269 function. For example, if 'some_value' represents a function that
1270 takes two integer parameters and returns a value, you can call
1271 that function like so:
1273 result = some_value (10,20)
1275 ** Module gdb.types has been added.
1276 It contains a collection of utilities for working with gdb.Types objects:
1277 get_basic_type, has_field, make_enum_dict.
1279 ** Module gdb.printing has been added.
1280 It contains utilities for writing and registering pretty-printers.
1281 New classes: PrettyPrinter, SubPrettyPrinter,
1282 RegexpCollectionPrettyPrinter.
1283 New function: register_pretty_printer.
1285 ** New commands "info pretty-printers", "enable pretty-printer" and
1286 "disable pretty-printer" have been added.
1288 ** gdb.parameter("directories") is now available.
1290 ** New function gdb.newest_frame returns the newest frame in the
1293 ** The gdb.InferiorThread class has a new "name" attribute. This
1294 holds the thread's name.
1296 ** Python Support for Inferior events.
1297 Python scripts can add observers to be notified of events
1298 occurring in the process being debugged.
1299 The following events are currently supported:
1300 - gdb.events.cont Continue event.
1301 - gdb.events.exited Inferior exited event.
1302 - gdb.events.stop Signal received, and Breakpoint hit events.
1306 ** GDB now puts template parameters in scope when debugging in an
1307 instantiation. For example, if you have:
1309 template<int X> int func (void) { return X; }
1311 then if you step into func<5>, "print X" will show "5". This
1312 feature requires proper debuginfo support from the compiler; it
1313 was added to GCC 4.5.
1315 ** The motion commands "next", "finish", "until", and "advance" now
1316 work better when exceptions are thrown. In particular, GDB will
1317 no longer lose control of the inferior; instead, the GDB will
1318 stop the inferior at the point at which the exception is caught.
1319 This functionality requires a change in the exception handling
1320 code that was introduced in GCC 4.5.
1322 * GDB now follows GCC's rules on accessing volatile objects when
1323 reading or writing target state during expression evaluation.
1324 One notable difference to prior behavior is that "print x = 0"
1325 no longer generates a read of x; the value of the assignment is
1326 now always taken directly from the value being assigned.
1328 * GDB now has some support for using labels in the program's source in
1329 linespecs. For instance, you can use "advance label" to continue
1330 execution to a label.
1332 * GDB now has support for reading and writing a new .gdb_index
1333 section. This section holds a fast index of DWARF debugging
1334 information and can be used to greatly speed up GDB startup and
1335 operation. See the documentation for `save gdb-index' for details.
1337 * The "watch" command now accepts an optional "-location" argument.
1338 When used, this causes GDB to watch the memory referred to by the
1339 expression. Such a watchpoint is never deleted due to it going out
1342 * GDB now supports thread debugging of core dumps on GNU/Linux.
1344 GDB now activates thread debugging using the libthread_db library
1345 when debugging GNU/Linux core dumps, similarly to when debugging
1346 live processes. As a result, when debugging a core dump file, GDB
1347 is now able to display pthread_t ids of threads. For example, "info
1348 threads" shows the same output as when debugging the process when it
1349 was live. In earlier releases, you'd see something like this:
1352 * 1 LWP 6780 main () at main.c:10
1354 While now you see this:
1357 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1359 It is also now possible to inspect TLS variables when debugging core
1362 When debugging a core dump generated on a machine other than the one
1363 used to run GDB, you may need to point GDB at the correct
1364 libthread_db library with the "set libthread-db-search-path"
1365 command. See the user manual for more details on this command.
1367 * When natively debugging programs on PowerPC BookE processors running
1368 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1369 which stop execution of the inferior whenever it executes an instruction
1370 at any address within the specified range. See the "PowerPC Embedded"
1371 section in the user manual for more details.
1373 * New features in the GDB remote stub, GDBserver
1375 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1376 and i686 LynxOS (version 5.x).
1378 ** GDBserver is now supported on Blackfin Linux.
1380 * New native configurations
1382 ia64 HP-UX ia64-*-hpux*
1386 Analog Devices, Inc. Blackfin Processor bfin-*
1388 * Ada task switching is now supported on sparc-elf targets when
1389 debugging a program using the Ravenscar Profile. For more information,
1390 see the "Tasking Support when using the Ravenscar Profile" section
1391 in the GDB user manual.
1393 * Guile support was removed.
1395 * New features in the GNU simulator
1397 ** The --map-info flag lists all known core mappings.
1399 ** CFI flashes may be simulated via the "cfi" device.
1401 *** Changes in GDB 7.2
1403 * Shared library support for remote targets by default
1405 When GDB is configured for a generic, non-OS specific target, like
1406 for example, --target=arm-eabi or one of the many *-*-elf targets,
1407 GDB now queries remote stubs for loaded shared libraries using the
1408 `qXfer:libraries:read' packet. Previously, shared library support
1409 was always disabled for such configurations.
1413 ** Argument Dependent Lookup (ADL)
1415 In C++ ADL lookup directs function search to the namespaces of its
1416 arguments even if the namespace has not been imported.
1426 Here the compiler will search for `foo' in the namespace of 'b'
1427 and find A::foo. GDB now supports this. This construct is commonly
1428 used in the Standard Template Library for operators.
1430 ** Improved User Defined Operator Support
1432 In addition to member operators, GDB now supports lookup of operators
1433 defined in a namespace and imported with a `using' directive, operators
1434 defined in the global scope, operators imported implicitly from an
1435 anonymous namespace, and the ADL operators mentioned in the previous
1437 GDB now also supports proper overload resolution for all the previously
1438 mentioned flavors of operators.
1440 ** static const class members
1442 Printing of static const class members that are initialized in the
1443 class definition has been fixed.
1445 * Windows Thread Information Block access.
1447 On Windows targets, GDB now supports displaying the Windows Thread
1448 Information Block (TIB) structure. This structure is visible either
1449 by using the new command `info w32 thread-information-block' or, by
1450 dereferencing the new convenience variable named `$_tlb', a
1451 thread-specific pointer to the TIB. This feature is also supported
1452 when remote debugging using GDBserver.
1454 * Static tracepoints
1456 Static tracepoints are calls in the user program into a tracing
1457 library. One such library is a port of the LTTng kernel tracer to
1458 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1459 When debugging with GDBserver, GDB now supports combining the GDB
1460 tracepoint machinery with such libraries. For example: the user can
1461 use GDB to probe a static tracepoint marker (a call from the user
1462 program into the tracing library) with the new "strace" command (see
1463 "New commands" below). This creates a "static tracepoint" in the
1464 breakpoint list, that can be manipulated with the same feature set
1465 as fast and regular tracepoints. E.g., collect registers, local and
1466 global variables, collect trace state variables, and define
1467 tracepoint conditions. In addition, the user can collect extra
1468 static tracepoint marker specific data, by collecting the new
1469 $_sdata internal variable. When analyzing the trace buffer, you can
1470 inspect $_sdata like any other variable available to GDB. For more
1471 information, see the "Tracepoints" chapter in GDB user manual. New
1472 remote packets have been defined to support static tracepoints, see
1473 the "New remote packets" section below.
1475 * Better reconstruction of tracepoints after disconnected tracing
1477 GDB will attempt to download the original source form of tracepoint
1478 definitions when starting a trace run, and then will upload these
1479 upon reconnection to the target, resulting in a more accurate
1480 reconstruction of the tracepoints that are in use on the target.
1484 You can now exercise direct control over the ways that GDB can
1485 affect your program. For instance, you can disallow the setting of
1486 breakpoints, so that the program can run continuously (assuming
1487 non-stop mode). In addition, the "observer" variable is available
1488 to switch all of the different controls; in observer mode, GDB
1489 cannot affect the target's behavior at all, which is useful for
1490 tasks like diagnosing live systems in the field.
1492 * The new convenience variable $_thread holds the number of the
1495 * New remote packets
1499 Return the address of the Windows Thread Information Block of a given thread.
1503 In response to several of the tracepoint packets, the target may now
1504 also respond with a number of intermediate `qRelocInsn' request
1505 packets before the final result packet, to have GDB handle
1506 relocating an instruction to execute at a different address. This
1507 is particularly useful for stubs that support fast tracepoints. GDB
1508 reports support for this feature in the qSupported packet.
1512 List static tracepoint markers in the target program.
1516 List static tracepoint markers at a given address in the target
1519 qXfer:statictrace:read
1521 Read the static trace data collected (by a `collect $_sdata'
1522 tracepoint action). The remote stub reports support for this packet
1523 to gdb's qSupported query.
1527 Send the current settings of GDB's permission flags.
1531 Send part of the source (textual) form of a tracepoint definition,
1532 which includes location, conditional, and action list.
1534 * The source command now accepts a -s option to force searching for the
1535 script in the source search path even if the script name specifies
1538 * New features in the GDB remote stub, GDBserver
1540 - GDBserver now support tracepoints (including fast tracepoints, and
1541 static tracepoints). The feature is currently supported by the
1542 i386-linux and amd64-linux builds. See the "Tracepoints support
1543 in gdbserver" section in the manual for more information.
1545 GDBserver JIT compiles the tracepoint's conditional agent
1546 expression bytecode into native code whenever possible for low
1547 overhead dynamic tracepoints conditionals. For such tracepoints,
1548 an expression that examines program state is evaluated when the
1549 tracepoint is reached, in order to determine whether to capture
1550 trace data. If the condition is simple and false, processing the
1551 tracepoint finishes very quickly and no data is gathered.
1553 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1554 for static tracepoints support.
1556 - GDBserver now supports x86_64 Windows 64-bit debugging.
1558 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1559 it understands register description.
1561 * The --batch flag now disables pagination and queries.
1563 * X86 general purpose registers
1565 GDB now supports reading/writing byte, word and double-word x86
1566 general purpose registers directly. This means you can use, say,
1567 $ah or $ax to refer, respectively, to the byte register AH and
1568 16-bit word register AX that are actually portions of the 32-bit
1569 register EAX or 64-bit register RAX.
1571 * The `commands' command now accepts a range of breakpoints to modify.
1572 A plain `commands' following a command that creates multiple
1573 breakpoints affects all the breakpoints set by that command. This
1574 applies to breakpoints set by `rbreak', and also applies when a
1575 single `break' command creates multiple breakpoints (e.g.,
1576 breakpoints on overloaded c++ functions).
1578 * The `rbreak' command now accepts a filename specification as part of
1579 its argument, limiting the functions selected by the regex to those
1580 in the specified file.
1582 * Support for remote debugging Windows and SymbianOS shared libraries
1583 from Unix hosts has been improved. Non Windows GDB builds now can
1584 understand target reported file names that follow MS-DOS based file
1585 system semantics, such as file names that include drive letters and
1586 use the backslash character as directory separator. This makes it
1587 possible to transparently use the "set sysroot" and "set
1588 solib-search-path" on Unix hosts to point as host copies of the
1589 target's shared libraries. See the new command "set
1590 target-file-system-kind" described below, and the "Commands to
1591 specify files" section in the user manual for more information.
1595 eval template, expressions...
1596 Convert the values of one or more expressions under the control
1597 of the string template to a command line, and call it.
1599 set target-file-system-kind unix|dos-based|auto
1600 show target-file-system-kind
1601 Set or show the assumed file system kind for target reported file
1604 save breakpoints <filename>
1605 Save all current breakpoint definitions to a file suitable for use
1606 in a later debugging session. To read the saved breakpoint
1607 definitions, use the `source' command.
1609 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1612 info static-tracepoint-markers
1613 Display information about static tracepoint markers in the target.
1615 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1616 Define a static tracepoint by probing a marker at the given
1617 function, line, address, or marker ID.
1621 Enable and disable observer mode.
1623 set may-write-registers on|off
1624 set may-write-memory on|off
1625 set may-insert-breakpoints on|off
1626 set may-insert-tracepoints on|off
1627 set may-insert-fast-tracepoints on|off
1628 set may-interrupt on|off
1629 Set individual permissions for GDB effects on the target. Note that
1630 some of these settings can have undesirable or surprising
1631 consequences, particularly when changed in the middle of a session.
1632 For instance, disabling the writing of memory can prevent
1633 breakpoints from being inserted, cause single-stepping to fail, or
1634 even crash your program, if you disable after breakpoints have been
1635 inserted. However, GDB should not crash.
1637 set record memory-query on|off
1638 show record memory-query
1639 Control whether to stop the inferior if memory changes caused
1640 by an instruction cannot be recorded.
1645 The disassemble command now supports "start,+length" form of two arguments.
1649 ** GDB now provides a new directory location, called the python directory,
1650 where Python scripts written for GDB can be installed. The location
1651 of that directory is <data-directory>/python, where <data-directory>
1652 is the GDB data directory. For more details, see section `Scripting
1653 GDB using Python' in the manual.
1655 ** The GDB Python API now has access to breakpoints, symbols, symbol
1656 tables, program spaces, inferiors, threads and frame's code blocks.
1657 Additionally, GDB Parameters can now be created from the API, and
1658 manipulated via set/show in the CLI.
1660 ** New functions gdb.target_charset, gdb.target_wide_charset,
1661 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1663 ** New exception gdb.GdbError.
1665 ** Pretty-printers are now also looked up in the current program space.
1667 ** Pretty-printers can now be individually enabled and disabled.
1669 ** GDB now looks for names of Python scripts to auto-load in a
1670 special section named `.debug_gdb_scripts', in addition to looking
1671 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1673 * Tracepoint actions were unified with breakpoint commands. In particular,
1674 there are no longer differences in "info break" output for breakpoints and
1675 tracepoints and the "commands" command can be used for both tracepoints and
1676 regular breakpoints.
1680 ARM Symbian arm*-*-symbianelf*
1682 * D language support.
1683 GDB now supports debugging programs written in the D programming
1686 * GDB now supports the extended ptrace interface for PowerPC which is
1687 available since Linux kernel version 2.6.34. This automatically enables
1688 any hardware breakpoints and additional hardware watchpoints available in
1689 the processor. The old ptrace interface exposes just one hardware
1690 watchpoint and no hardware breakpoints.
1692 * GDB is now able to use the Data Value Compare (DVC) register available on
1693 embedded PowerPC processors to implement in hardware simple watchpoint
1694 conditions of the form:
1696 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1698 This works in native GDB running on Linux kernels with the extended ptrace
1699 interface mentioned above.
1701 *** Changes in GDB 7.1
1705 ** Namespace Support
1707 GDB now supports importing of namespaces in C++. This enables the
1708 user to inspect variables from imported namespaces. Support for
1709 namepace aliasing has also been added. So, if a namespace is
1710 aliased in the current scope (e.g. namepace C=A; ) the user can
1711 print variables using the alias (e.g. (gdb) print C::x).
1715 All known bugs relating to the printing of virtual base class were
1716 fixed. It is now possible to call overloaded static methods using a
1721 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1722 and reinterpret_cast<> are now handled by the C++ expression parser.
1726 Xilinx MicroBlaze microblaze-*-*
1731 Xilinx MicroBlaze microblaze
1734 * Multi-program debugging.
1736 GDB now has support for multi-program (a.k.a. multi-executable or
1737 multi-exec) debugging. This allows for debugging multiple inferiors
1738 simultaneously each running a different program under the same GDB
1739 session. See "Debugging Multiple Inferiors and Programs" in the
1740 manual for more information. This implied some user visible changes
1741 in the multi-inferior support. For example, "info inferiors" now
1742 lists inferiors that are not running yet or that have exited
1743 already. See also "New commands" and "New options" below.
1745 * New tracing features
1747 GDB's tracepoint facility now includes several new features:
1749 ** Trace state variables
1751 GDB tracepoints now include support for trace state variables, which
1752 are variables managed by the target agent during a tracing
1753 experiment. They are useful for tracepoints that trigger each
1754 other, so for instance one tracepoint can count hits in a variable,
1755 and then a second tracepoint has a condition that is true when the
1756 count reaches a particular value. Trace state variables share the
1757 $-syntax of GDB convenience variables, and can appear in both
1758 tracepoint actions and condition expressions. Use the "tvariable"
1759 command to create, and "info tvariables" to view; see "Trace State
1760 Variables" in the manual for more detail.
1764 GDB now includes an option for defining fast tracepoints, which
1765 targets may implement more efficiently, such as by installing a jump
1766 into the target agent rather than a trap instruction. The resulting
1767 speedup can be by two orders of magnitude or more, although the
1768 tradeoff is that some program locations on some target architectures
1769 might not allow fast tracepoint installation, for instance if the
1770 instruction to be replaced is shorter than the jump. To request a
1771 fast tracepoint, use the "ftrace" command, with syntax identical to
1772 the regular trace command.
1774 ** Disconnected tracing
1776 It is now possible to detach GDB from the target while it is running
1777 a trace experiment, then reconnect later to see how the experiment
1778 is going. In addition, a new variable disconnected-tracing lets you
1779 tell the target agent whether to continue running a trace if the
1780 connection is lost unexpectedly.
1784 GDB now has the ability to save the trace buffer into a file, and
1785 then use that file as a target, similarly to you can do with
1786 corefiles. You can select trace frames, print data that was
1787 collected in them, and use tstatus to display the state of the
1788 tracing run at the moment that it was saved. To create a trace
1789 file, use "tsave <filename>", and to use it, do "target tfile
1792 ** Circular trace buffer
1794 You can ask the target agent to handle the trace buffer as a
1795 circular buffer, discarding the oldest trace frames to make room for
1796 newer ones, by setting circular-trace-buffer to on. This feature may
1797 not be available for all target agents.
1802 The disassemble command, when invoked with two arguments, now requires
1803 the arguments to be comma-separated.
1806 The info variables command now displays variable definitions. Files
1807 which only declare a variable are not shown.
1810 The source command is now capable of sourcing Python scripts.
1811 This feature is dependent on the debugger being build with Python
1814 Related to this enhancement is also the introduction of a new command
1815 "set script-extension" (see below).
1817 * New commands (for set/show, see "New options" below)
1819 record save [<FILENAME>]
1820 Save a file (in core file format) containing the process record
1821 execution log for replay debugging at a later time.
1823 record restore <FILENAME>
1824 Restore the process record execution log that was saved at an
1825 earlier time, for replay debugging.
1827 add-inferior [-copies <N>] [-exec <FILENAME>]
1830 clone-inferior [-copies <N>] [ID]
1831 Make a new inferior ready to execute the same program another
1832 inferior has loaded.
1837 maint info program-spaces
1838 List the program spaces loaded into GDB.
1840 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1841 show remote interrupt-sequence
1842 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1843 as the sequence to the remote target in order to interrupt the execution.
1844 Ctrl-C is a default. Some system prefers BREAK which is high level of
1845 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1846 Magic SysRq g. It is BREAK signal and character 'g'.
1848 set remote interrupt-on-connect [on | off]
1849 show remote interrupt-on-connect
1850 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1851 remote target when gdb connects to it. This is needed when you debug
1854 set remotebreak [on | off]
1856 Deprecated. Use "set/show remote interrupt-sequence" instead.
1858 tvariable $NAME [ = EXP ]
1859 Create or modify a trace state variable.
1862 List trace state variables and their values.
1864 delete tvariable $NAME ...
1865 Delete one or more trace state variables.
1868 Evaluate the given expressions without collecting anything into the
1869 trace buffer. (Valid in tracepoint actions only.)
1871 ftrace FN / FILE:LINE / *ADDR
1872 Define a fast tracepoint at the given function, line, or address.
1874 * New expression syntax
1876 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1877 GDB now parses 0b101010 identically with 42.
1881 set follow-exec-mode new|same
1882 show follow-exec-mode
1883 Control whether GDB reuses the same inferior across an exec call or
1884 creates a new one. This is useful to be able to restart the old
1885 executable after the inferior having done an exec call.
1887 set default-collect EXPR, ...
1888 show default-collect
1889 Define a list of expressions to be collected at each tracepoint.
1890 This is a useful way to ensure essential items are not overlooked,
1891 such as registers or a critical global variable.
1893 set disconnected-tracing
1894 show disconnected-tracing
1895 If set to 1, the target is instructed to continue tracing if it
1896 loses its connection to GDB. If 0, the target is to stop tracing
1899 set circular-trace-buffer
1900 show circular-trace-buffer
1901 If set to on, the target is instructed to use a circular trace buffer
1902 and discard the oldest trace frames instead of stopping the trace due
1903 to a full trace buffer. If set to off, the trace stops when the buffer
1904 fills up. Some targets may not support this.
1906 set script-extension off|soft|strict
1907 show script-extension
1908 If set to "off", the debugger does not perform any script language
1909 recognition, and all sourced files are assumed to be GDB scripts.
1910 If set to "soft" (the default), files are sourced according to
1911 filename extension, falling back to GDB scripts if the first
1913 If set to "strict", files are sourced according to filename extension.
1915 set ada trust-PAD-over-XVS on|off
1916 show ada trust-PAD-over-XVS
1917 If off, activate a workaround against a bug in the debugging information
1918 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1919 the GCC sources for more information about the GNAT encoding and
1920 PAD types in particular). It is always safe to set this option to
1921 off, but this introduces a slight performance penalty. The default
1924 * Python API Improvements
1926 ** GDB provides the new class gdb.LazyString. This is useful in
1927 some pretty-printing cases. The new method gdb.Value.lazy_string
1928 provides a simple way to create objects of this type.
1930 ** The fields returned by gdb.Type.fields now have an
1931 `is_base_class' attribute.
1933 ** The new method gdb.Type.range returns the range of an array type.
1935 ** The new method gdb.parse_and_eval can be used to parse and
1936 evaluate an expression.
1938 * New remote packets
1941 Define a trace state variable.
1944 Get the current value of a trace state variable.
1947 Set desired tracing behavior upon disconnection.
1950 Set the trace buffer to be linear or circular.
1953 Get data about the tracepoints currently in use.
1957 Process record now works correctly with hardware watchpoints.
1959 Multiple bug fixes have been made to the mips-irix port, making it
1960 much more reliable. In particular:
1961 - Debugging threaded applications is now possible again. Previously,
1962 GDB would hang while starting the program, or while waiting for
1963 the program to stop at a breakpoint.
1964 - Attaching to a running process no longer hangs.
1965 - An error occurring while loading a core file has been fixed.
1966 - Changing the value of the PC register now works again. This fixes
1967 problems observed when using the "jump" command, or when calling
1968 a function from GDB, or even when assigning a new value to $pc.
1969 - With the "finish" and "return" commands, the return value for functions
1970 returning a small array is now correctly printed.
1971 - It is now possible to break on shared library code which gets executed
1972 during a shared library init phase (code executed while executing
1973 their .init section). Previously, the breakpoint would have no effect.
1974 - GDB is now able to backtrace through the signal handler for
1975 non-threaded programs.
1977 PIE (Position Independent Executable) programs debugging is now supported.
1978 This includes debugging execution of PIC (Position Independent Code) shared
1979 libraries although for that, it should be possible to run such libraries as an
1982 *** Changes in GDB 7.0
1984 * GDB now has an interface for JIT compilation. Applications that
1985 dynamically generate code can create symbol files in memory and register
1986 them with GDB. For users, the feature should work transparently, and
1987 for JIT developers, the interface is documented in the GDB manual in the
1988 "JIT Compilation Interface" chapter.
1990 * Tracepoints may now be conditional. The syntax is as for
1991 breakpoints; either an "if" clause appended to the "trace" command,
1992 or the "condition" command is available. GDB sends the condition to
1993 the target for evaluation using the same bytecode format as is used
1994 for tracepoint actions.
1996 * The disassemble command now supports: an optional /r modifier, print the
1997 raw instructions in hex as well as in symbolic form, and an optional /m
1998 modifier to print mixed source+assembly.
2000 * Process record and replay
2002 In a architecture environment that supports ``process record and
2003 replay'', ``process record and replay'' target can record a log of
2004 the process execution, and replay it with both forward and reverse
2007 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2008 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2009 set execution-direction {forward|reverse}, for targets that support
2012 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2013 feature is available with a native GDB running on kernel version
2016 * GDB now has support for multi-byte and wide character sets on the
2017 target. Strings whose character type is wchar_t, char16_t, or
2018 char32_t are now correctly printed. GDB supports wide- and unicode-
2019 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2020 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2021 `printf'. This feature requires iconv to work properly; if your
2022 system does not have a working iconv, GDB can use GNU libiconv. See
2023 the installation instructions for more information.
2025 * GDB now supports automatic retrieval of shared library files from
2026 remote targets. To use this feature, specify a system root that begins
2027 with the `remote:' prefix, either via the `set sysroot' command or via
2028 the `--with-sysroot' configure-time option.
2030 * "info sharedlibrary" now takes an optional regex of libraries to show,
2031 and it now reports if a shared library has no debugging information.
2033 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2034 now complete on file names.
2036 * When completing in expressions, gdb will attempt to limit
2037 completions to allowable structure or union fields, where appropriate.
2038 For instance, consider:
2040 # struct example { int f1; double f2; };
2041 # struct example variable;
2044 If the user types TAB at the end of this command line, the available
2045 completions will be "f1" and "f2".
2047 * Inlined functions are now supported. They show up in backtraces, and
2048 the "step", "next", and "finish" commands handle them automatically.
2050 * GDB now supports the token-splicing (##) and stringification (#)
2051 operators when expanding macros. It also supports variable-arity
2054 * GDB now supports inspecting extra signal information, exported by
2055 the new $_siginfo convenience variable. The feature is currently
2056 implemented on linux ARM, i386 and amd64.
2058 * GDB can now display the VFP floating point registers and NEON vector
2059 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2060 can provide these registers (requires Linux 2.6.30 or later). Remote
2061 and simulator targets may also provide them.
2063 * New remote packets
2066 Search memory for a sequence of bytes.
2069 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2070 operation over reliable transport links. Use of this packet is
2071 controlled by the `set remote noack-packet' command.
2074 Kill the process with the specified process ID. Use this in preference
2075 to `k' when multiprocess protocol extensions are supported.
2078 Obtains additional operating system information
2082 Read or write additional signal information.
2084 * Removed remote protocol undocumented extension
2086 An undocumented extension to the remote protocol's `S' stop reply
2087 packet that permited the stub to pass a process id was removed.
2088 Remote servers should use the `T' stop reply packet instead.
2090 * GDB now supports multiple function calling conventions according to the
2091 DWARF-2 DW_AT_calling_convention function attribute.
2093 * The SH target utilizes the aforementioned change to distinguish between gcc
2094 and Renesas calling convention. It also adds the new CLI commands
2095 `set/show sh calling-convention'.
2097 * GDB can now read compressed debug sections, as produced by GNU gold
2098 with the --compress-debug-sections=zlib flag.
2100 * 64-bit core files are now supported on AIX.
2102 * Thread switching is now supported on Tru64.
2104 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2105 which will be allocated using malloc later in program execution.
2107 * The qXfer:libraries:read remote procotol packet now allows passing a
2108 list of section offsets.
2110 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2111 conditions handling signals delivered during attach or thread creation
2112 have also been fixed.
2114 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2115 From the user's standpoint, all unqualified instances of True and False
2116 are treated as the standard definitions, regardless of context.
2118 * GDB now parses C++ symbol and type names more flexibly. For
2121 template<typename T> class C { };
2124 GDB will now correctly handle all of:
2126 ptype C<char const *>
2127 ptype C<char const*>
2128 ptype C<const char *>
2129 ptype C<const char*>
2131 * New features in the GDB remote stub, gdbserver
2133 - The "--wrapper" command-line argument tells gdbserver to use a
2134 wrapper program to launch programs for debugging.
2136 - On PowerPC and S/390 targets, it is now possible to use a single
2137 gdbserver executable to debug both 32-bit and 64-bit programs.
2138 (This requires gdbserver itself to be built as a 64-bit executable.)
2140 - gdbserver uses the new noack protocol mode for TCP connections to
2141 reduce communications latency, if also supported and enabled in GDB.
2143 - Support for the sparc64-linux-gnu target is now included in
2146 - The amd64-linux build of gdbserver now supports debugging both
2147 32-bit and 64-bit programs.
2149 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2150 now support hardware watchpoints, and will use them automatically
2155 GDB now has support for scripting using Python. Whether this is
2156 available is determined at configure time.
2158 New GDB commands can now be written in Python.
2160 * Ada tasking support
2162 Ada tasks can now be inspected in GDB. The following commands have
2166 Print the list of Ada tasks.
2168 Print detailed information about task number N.
2170 Print the task number of the current task.
2172 Switch the context of debugging to task number N.
2174 * Support for user-defined prefixed commands. The "define" command can
2175 add new commands to existing prefixes, e.g. "target".
2177 * Multi-inferior, multi-process debugging.
2179 GDB now has generalized support for multi-inferior debugging. See
2180 "Debugging Multiple Inferiors" in the manual for more information.
2181 Although availability still depends on target support, the command
2182 set is more uniform now. The GNU/Linux specific multi-forks support
2183 has been migrated to this new framework. This implied some user
2184 visible changes; see "New commands" and also "Removed commands"
2187 * Target descriptions can now describe the target OS ABI. See the
2188 "Target Description Format" section in the user manual for more
2191 * Target descriptions can now describe "compatible" architectures
2192 to indicate that the target can execute applications for a different
2193 architecture in addition to those for the main target architecture.
2194 See the "Target Description Format" section in the user manual for
2197 * Multi-architecture debugging.
2199 GDB now includes general supports for debugging applications on
2200 hybrid systems that use more than one single processor architecture
2201 at the same time. Each such hybrid architecture still requires
2202 specific support to be added. The only hybrid architecture supported
2203 in this version of GDB is the Cell Broadband Engine.
2205 * GDB now supports integrated debugging of Cell/B.E. applications that
2206 use both the PPU and SPU architectures. To enable support for hybrid
2207 Cell/B.E. debugging, you need to configure GDB to support both the
2208 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2209 --enable-targets configure option.
2211 * Non-stop mode debugging.
2213 For some targets, GDB now supports an optional mode of operation in
2214 which you can examine stopped threads while other threads continue
2215 to execute freely. This is referred to as non-stop mode, with the
2216 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2217 section in the user manual for more information.
2219 To be able to support remote non-stop debugging, a remote stub needs
2220 to implement the non-stop mode remote protocol extensions, as
2221 described in the "Remote Non-Stop" section of the user manual. The
2222 GDB remote stub, gdbserver, has been adjusted to support these
2223 extensions on linux targets.
2225 * New commands (for set/show, see "New options" below)
2227 catch syscall [NAME(S) | NUMBER(S)]
2228 Catch system calls. Arguments, which should be names of system
2229 calls or their numbers, mean catch only those syscalls. Without
2230 arguments, every syscall will be caught. When the inferior issues
2231 any of the specified syscalls, GDB will stop and announce the system
2232 call, both when it is called and when its call returns. This
2233 feature is currently available with a native GDB running on the
2234 Linux Kernel, under the following architectures: x86, x86_64,
2235 PowerPC and PowerPC64.
2237 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2239 Search memory for a sequence of bytes.
2241 maint set python print-stack
2242 maint show python print-stack
2243 Show a stack trace when an error is encountered in a Python script.
2246 Invoke CODE by passing it to the Python interpreter.
2251 These allow macros to be defined, undefined, and listed
2255 Show operating system information about processes.
2258 List the inferiors currently under GDB's control.
2261 Switch focus to inferior number NUM.
2264 Detach from inferior number NUM.
2267 Kill inferior number NUM.
2271 set spu stop-on-load
2272 show spu stop-on-load
2273 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2275 set spu auto-flush-cache
2276 show spu auto-flush-cache
2277 Control whether to automatically flush the software-managed cache
2278 during Cell/B.E. debugging.
2280 set sh calling-convention
2281 show sh calling-convention
2282 Control the calling convention used when calling SH target functions.
2285 show debug timestamp
2286 Control display of timestamps with GDB debugging output.
2288 set disassemble-next-line
2289 show disassemble-next-line
2290 Control display of disassembled source lines or instructions when
2293 set remote noack-packet
2294 show remote noack-packet
2295 Set/show the use of remote protocol QStartNoAckMode packet. See above
2296 under "New remote packets."
2298 set remote query-attached-packet
2299 show remote query-attached-packet
2300 Control use of remote protocol `qAttached' (query-attached) packet.
2302 set remote read-siginfo-object
2303 show remote read-siginfo-object
2304 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2307 set remote write-siginfo-object
2308 show remote write-siginfo-object
2309 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2312 set remote reverse-continue
2313 show remote reverse-continue
2314 Control use of remote protocol 'bc' (reverse-continue) packet.
2316 set remote reverse-step
2317 show remote reverse-step
2318 Control use of remote protocol 'bs' (reverse-step) packet.
2320 set displaced-stepping
2321 show displaced-stepping
2322 Control displaced stepping mode. Displaced stepping is a way to
2323 single-step over breakpoints without removing them from the debuggee.
2324 Also known as "out-of-line single-stepping".
2327 show debug displaced
2328 Control display of debugging info for displaced stepping.
2330 maint set internal-error
2331 maint show internal-error
2332 Control what GDB does when an internal error is detected.
2334 maint set internal-warning
2335 maint show internal-warning
2336 Control what GDB does when an internal warning is detected.
2341 Use a wrapper program to launch programs for debugging.
2343 set multiple-symbols (all|ask|cancel)
2344 show multiple-symbols
2345 The value of this variable can be changed to adjust the debugger behavior
2346 when an expression or a breakpoint location contains an ambiguous symbol
2347 name (an overloaded function name, for instance).
2349 set breakpoint always-inserted
2350 show breakpoint always-inserted
2351 Keep breakpoints always inserted in the target, as opposed to inserting
2352 them when resuming the target, and removing them when the target stops.
2353 This option can improve debugger performance on slow remote targets.
2355 set arm fallback-mode (arm|thumb|auto)
2356 show arm fallback-mode
2357 set arm force-mode (arm|thumb|auto)
2359 These commands control how ARM GDB determines whether instructions
2360 are ARM or Thumb. The default for both settings is auto, which uses
2361 the current CPSR value for instructions without symbols; previous
2362 versions of GDB behaved as if "set arm fallback-mode arm".
2364 set disable-randomization
2365 show disable-randomization
2366 Standalone programs run with the virtual address space randomization enabled
2367 by default on some platforms. This option keeps the addresses stable across
2368 multiple debugging sessions.
2372 Control whether other threads are stopped or not when some thread hits
2377 Requests that asynchronous execution is enabled in the target, if available.
2378 In this case, it's possible to resume target in the background, and interact
2379 with GDB while the target is running. "show target-async" displays the
2380 current state of asynchronous execution of the target.
2382 set target-wide-charset
2383 show target-wide-charset
2384 The target-wide-charset is the name of the character set that GDB
2385 uses when printing characters whose type is wchar_t.
2387 set tcp auto-retry (on|off)
2389 set tcp connect-timeout
2390 show tcp connect-timeout
2391 These commands allow GDB to retry failed TCP connections to a remote stub
2392 with a specified timeout period; this is useful if the stub is launched
2393 in parallel with GDB but may not be ready to accept connections immediately.
2395 set libthread-db-search-path
2396 show libthread-db-search-path
2397 Control list of directories which GDB will search for appropriate
2400 set schedule-multiple (on|off)
2401 show schedule-multiple
2402 Allow GDB to resume all threads of all processes or only threads of
2403 the current process.
2407 Use more aggressive caching for accesses to the stack. This improves
2408 performance of remote debugging (particularly backtraces) without
2409 affecting correctness.
2411 set interactive-mode (on|off|auto)
2412 show interactive-mode
2413 Control whether GDB runs in interactive mode (on) or not (off).
2414 When in interactive mode, GDB waits for the user to answer all
2415 queries. Otherwise, GDB does not wait and assumes the default
2416 answer. When set to auto (the default), GDB determines which
2417 mode to use based on the stdin settings.
2422 For program forks, this is replaced by the new more generic `info
2423 inferiors' command. To list checkpoints, you can still use the
2424 `info checkpoints' command, which was an alias for the `info forks'
2428 Replaced by the new `inferior' command. To switch between
2429 checkpoints, you can still use the `restart' command, which was an
2430 alias for the `fork' command.
2433 This is removed, since some targets don't have a notion of
2434 processes. To switch between processes, you can still use the
2435 `inferior' command using GDB's own inferior number.
2438 For program forks, this is replaced by the new more generic `kill
2439 inferior' command. To delete a checkpoint, you can still use the
2440 `delete checkpoint' command, which was an alias for the `delete
2444 For program forks, this is replaced by the new more generic `detach
2445 inferior' command. To detach a checkpoint, you can still use the
2446 `detach checkpoint' command, which was an alias for the `detach
2449 * New native configurations
2451 x86/x86_64 Darwin i[34567]86-*-darwin*
2453 x86_64 MinGW x86_64-*-mingw*
2457 Lattice Mico32 lm32-*
2458 x86 DICOS i[34567]86-*-dicos*
2459 x86_64 DICOS x86_64-*-dicos*
2462 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2463 (mingw32ce) debugging.
2469 These commands were actually not implemented on any target.
2471 *** Changes in GDB 6.8
2473 * New native configurations
2475 NetBSD/hppa hppa*-*netbsd*
2476 Xtensa GNU/Linux xtensa*-*-linux*
2480 NetBSD/hppa hppa*-*-netbsd*
2481 Xtensa GNU/Lunux xtensa*-*-linux*
2483 * Change in command line behavior -- corefiles vs. process ids.
2485 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2486 attaching to process NUMBER fails, GDB no longer attempts to open a
2487 core file named NUMBER. Attaching to a program using the -c option
2488 is no longer supported. Instead, use the '-p' or '--pid' options.
2490 * GDB can now be built as a native debugger for debugging Windows x86
2491 (mingw32) Portable Executable (PE) programs.
2493 * Pending breakpoints no longer change their number when their address
2496 * GDB now supports breakpoints with multiple locations,
2497 including breakpoints on C++ constructors, inside C++ templates,
2498 and in inlined functions.
2500 * GDB's ability to debug optimized code has been improved. GDB more
2501 accurately identifies function bodies and lexical blocks that occupy
2502 more than one contiguous range of addresses.
2504 * Target descriptions can now describe registers for PowerPC.
2506 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2507 registers on PowerPC targets.
2509 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2510 targets even when the libthread_db library is not available.
2512 * The GDB remote stub, gdbserver, now supports the new file transfer
2513 commands (remote put, remote get, and remote delete).
2515 * The GDB remote stub, gdbserver, now supports run and attach in
2516 extended-remote mode.
2518 * hppa*64*-*-hpux11* target broken
2519 The debugger is unable to start a program and fails with the following
2520 error: "Error trying to get information about dynamic linker".
2521 The gdb-6.7 release is also affected.
2523 * GDB now supports the --enable-targets= configure option to allow
2524 building a single GDB executable that supports multiple remote
2525 target architectures.
2527 * GDB now supports debugging C and C++ programs which use the
2528 Decimal Floating Point extension. In addition, the PowerPC target
2529 now has a set of pseudo-registers to inspect decimal float values
2530 stored in two consecutive float registers.
2532 * The -break-insert MI command can optionally create pending
2535 * Improved support for debugging Ada
2536 Many improvements to the Ada language support have been made. These
2538 - Better support for Ada2005 interface types
2539 - Improved handling of arrays and slices in general
2540 - Better support for Taft-amendment types
2541 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2543 - Improved command completion in Ada
2546 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2551 set print frame-arguments (all|scalars|none)
2552 show print frame-arguments
2553 The value of this variable can be changed to control which argument
2554 values should be printed by the debugger when displaying a frame.
2559 Transfer files to and from a remote target, and delete remote files.
2566 Transfer files to and from a remote target, and delete remote files.
2568 * New remote packets
2575 Open, close, read, write, and delete files on the remote system.
2578 Attach to an existing process on the remote system, in extended-remote
2582 Run a new process on the remote system, in extended-remote mode.
2584 *** Changes in GDB 6.7
2586 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2587 bfd, libiberty and opcodes, as revealed by static analysis donated by
2588 Coverity, Inc. (http://scan.coverity.com).
2590 * When looking up multiply-defined global symbols, GDB will now prefer the
2591 symbol definition in the current shared library if it was built using the
2592 -Bsymbolic linker option.
2594 * When the Text User Interface (TUI) is not configured, GDB will now
2595 recognize the -tui command-line option and print a message that the TUI
2598 * The GDB remote stub, gdbserver, now has lower overhead for high
2599 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2601 * GDB for MIPS targets now autodetects whether a remote target provides
2602 32-bit or 64-bit register values.
2604 * Support for C++ member pointers has been improved.
2606 * GDB now understands XML target descriptions, which specify the
2607 target's overall architecture. GDB can read a description from
2608 a local file or over the remote serial protocol.
2610 * Vectors of single-byte data use a new integer type which is not
2611 automatically displayed as character or string data.
2613 * The /s format now works with the print command. It displays
2614 arrays of single-byte integers and pointers to single-byte integers
2617 * Target descriptions can now describe target-specific registers,
2618 for architectures which have implemented the support (currently
2619 only ARM, M68K, and MIPS).
2621 * GDB and the GDB remote stub, gdbserver, now support the XScale
2624 * The GDB remote stub, gdbserver, has been updated to support
2625 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2626 has been rewritten to use the standard GDB remote protocol.
2628 * GDB can now step into C++ functions which are called through thunks.
2630 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2632 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2633 layout. It also supports a TextSeg= and DataSeg= response when only
2634 segment base addresses (rather than offsets) are available.
2636 * The /i format now outputs any trailing branch delay slot instructions
2637 immediately following the last instruction within the count specified.
2639 * The GDB remote protocol "T" stop reply packet now supports a
2640 "library" response. Combined with the new "qXfer:libraries:read"
2641 packet, this response allows GDB to debug shared libraries on targets
2642 where the operating system manages the list of loaded libraries (e.g.
2643 Windows and SymbianOS).
2645 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2646 (DLLs) on Windows and Windows CE targets.
2648 * GDB now supports a faster verification that a .debug file matches its binary
2649 according to its build-id signature, if the signature is present.
2655 Enable or disable hardware flow control (RTS/CTS) on the serial port
2656 when debugging using remote targets.
2658 set mem inaccessible-by-default
2659 show mem inaccessible-by-default
2660 If the target supplies a memory map, for instance via the remote
2661 protocol's "qXfer:memory-map:read" packet, setting this variable
2662 prevents GDB from accessing memory outside the memory map. This
2663 is useful for targets with memory mapped registers or which react
2664 badly to accesses of unmapped address space.
2666 set breakpoint auto-hw
2667 show breakpoint auto-hw
2668 If the target supplies a memory map, for instance via the remote
2669 protocol's "qXfer:memory-map:read" packet, setting this variable
2670 lets GDB use hardware breakpoints automatically for memory regions
2671 where it can not use software breakpoints. This covers both the
2672 "break" command and internal breakpoints used for other commands
2673 including "next" and "finish".
2676 catch exception unhandled
2677 Stop the program execution when Ada exceptions are raised.
2680 Stop the program execution when an Ada assertion failed.
2684 Set an alternate system root for target files. This is a more
2685 general version of "set solib-absolute-prefix", which is now
2686 an alias to "set sysroot".
2689 Provide extended SPU facility status information. This set of
2690 commands is available only when debugging the Cell/B.E. SPU
2693 * New native configurations
2695 OpenBSD/sh sh*-*openbsd*
2698 unset tdesc filename
2700 Use the specified local file as an XML target description, and do
2701 not query the target for its built-in description.
2705 OpenBSD/sh sh*-*-openbsd*
2706 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2707 Toshiba Media Processor mep-elf
2709 * New remote packets
2712 Ignore the specified signals; pass them directly to the debugged program
2713 without stopping other threads or reporting them to GDB.
2715 qXfer:features:read:
2716 Read an XML target description from the target, which describes its
2721 Read or write contents of an spufs file on the target system. These
2722 packets are available only on the Cell/B.E. SPU architecture.
2724 qXfer:libraries:read:
2725 Report the loaded shared libraries. Combined with new "T" packet
2726 response, this packet allows GDB to debug shared libraries on
2727 targets where the operating system manages the list of loaded
2728 libraries (e.g. Windows and SymbianOS).
2732 Support for these obsolete configurations has been removed.
2740 i[34567]86-*-lynxos*
2741 i[34567]86-*-netware*
2742 i[34567]86-*-sco3.2v5*
2743 i[34567]86-*-sco3.2v4*
2745 i[34567]86-*-sysv4.2*
2748 i[34567]86-*-unixware2*
2749 i[34567]86-*-unixware*
2758 * Other removed features
2765 Various m68k-only ROM monitors.
2772 Various Renesas ROM monitors and debugging interfaces for SH and
2777 Support for a Macraigor serial interface to on-chip debugging.
2778 GDB does not directly support the newer parallel or USB
2783 A debug information format. The predecessor to DWARF 2 and
2784 DWARF 3, which are still supported.
2786 Support for the HP aCC compiler on HP-UX/PA-RISC
2788 SOM-encapsulated symbolic debugging information, automatic
2789 invocation of pxdb, and the aCC custom C++ ABI. This does not
2790 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2791 with aCC can still be debugged on an assembly level.
2793 MIPS ".pdr" sections
2795 A MIPS-specific format used to describe stack frame layout
2796 in debugging information.
2800 GDB could work with an older version of Guile to debug
2801 the interpreter and Scheme programs running in it.
2803 set mips stack-arg-size
2804 set mips saved-gpreg-size
2806 Use "set mips abi" to control parameter passing for MIPS.
2808 *** Changes in GDB 6.6
2813 Cell Broadband Engine SPU spu-elf
2815 * GDB can now be configured as a cross-debugger targeting native Windows
2816 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2817 running on a Windows system over TCP/IP to debug Windows programs.
2819 * The GDB remote stub, gdbserver, has been updated to support Windows and
2820 Cygwin debugging. Both single-threaded and multi-threaded programs are
2823 * The "set trust-readonly-sections" command works again. This command was
2824 broken in GDB 6.3, 6.4, and 6.5.
2826 * The "load" command now supports writing to flash memory, if the remote
2827 stub provides the required support.
2829 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2830 longer requires symbolic debug information (e.g. DWARF-2).
2835 unset substitute-path
2836 show substitute-path
2837 Manage a list of substitution rules that GDB uses to rewrite the name
2838 of the directories where the sources are located. This can be useful
2839 for instance when the sources were moved to a different location
2840 between compilation and debugging.
2844 Print each CLI command as it is executed. Each command is prefixed with
2845 a number of `+' symbols representing the nesting depth.
2846 The source command now has a `-v' option to enable the same feature.
2850 The ARM Demon monitor support (RDP protocol, "target rdp").
2852 Kernel Object Display, an embedded debugging feature which only worked with
2853 an obsolete version of Cisco IOS.
2855 The 'set download-write-size' and 'show download-write-size' commands.
2857 * New remote packets
2860 Tell a stub about GDB client features, and request remote target features.
2861 The first feature implemented is PacketSize, which allows the target to
2862 specify the size of packets it can handle - to minimize the number of
2863 packets required and improve performance when connected to a remote
2867 Fetch an OS auxilliary vector from the remote stub. This packet is a
2868 more efficient replacement for qPart:auxv:read.
2870 qXfer:memory-map:read:
2871 Fetch a memory map from the remote stub, including information about
2872 RAM, ROM, and flash memory devices.
2877 Erase and program a flash memory device.
2879 * Removed remote packets
2882 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2883 used it, and only gdbserver implemented it.
2885 *** Changes in GDB 6.5
2889 Renesas M32C/M16C m32c-elf
2891 Morpho Technologies ms1 ms1-elf
2895 init-if-undefined Initialize a convenience variable, but
2896 only if it doesn't already have a value.
2898 The following commands are presently only implemented for native GNU/Linux:
2900 checkpoint Save a snapshot of the program state.
2902 restart <n> Return the program state to a
2903 previously saved state.
2905 info checkpoints List currently saved checkpoints.
2907 delete-checkpoint <n> Delete a previously saved checkpoint.
2909 set|show detach-on-fork Tell gdb whether to detach from a newly
2910 forked process, or to keep debugging it.
2912 info forks List forks of the user program that
2913 are available to be debugged.
2915 fork <n> Switch to debugging one of several
2916 forks of the user program that are
2917 available to be debugged.
2919 delete-fork <n> Delete a fork from the list of forks
2920 that are available to be debugged (and
2921 kill the forked process).
2923 detach-fork <n> Delete a fork from the list of forks
2924 that are available to be debugged (and
2925 allow the process to continue).
2929 Morpho Technologies ms2 ms1-elf
2931 * Improved Windows host support
2933 GDB now builds as a cross debugger hosted on i686-mingw32, including
2934 native console support, and remote communications using either
2935 network sockets or serial ports.
2937 * Improved Modula-2 language support
2939 GDB can now print most types in the Modula-2 syntax. This includes:
2940 basic types, set types, record types, enumerated types, range types,
2941 pointer types and ARRAY types. Procedure var parameters are correctly
2942 printed and hexadecimal addresses and character constants are also
2943 written in the Modula-2 syntax. Best results can be obtained by using
2944 GNU Modula-2 together with the -gdwarf-2 command line option.
2948 The ARM rdi-share module.
2950 The Netware NLM debug server.
2952 *** Changes in GDB 6.4
2954 * New native configurations
2956 OpenBSD/arm arm*-*-openbsd*
2957 OpenBSD/mips64 mips64-*-openbsd*
2961 Morpho Technologies ms1 ms1-elf
2963 * New command line options
2965 --batch-silent As for --batch, but totally silent.
2966 --return-child-result The debugger will exist with the same value
2967 the child (debugged) program exited with.
2968 --eval-command COMMAND, -ex COMMAND
2969 Execute a single GDB CLI command. This may be
2970 specified multiple times and in conjunction
2971 with the --command (-x) option.
2973 * Deprecated commands removed
2975 The following commands, that were deprecated in 2000, have been
2979 set|show arm disassembly-flavor set|show arm disassembler
2980 othernames set arm disassembler
2981 set|show remotedebug set|show debug remote
2982 set|show archdebug set|show debug arch
2983 set|show eventdebug set|show debug event
2986 * New BSD user-level threads support
2988 It is now possible to debug programs using the user-level threads
2989 library on OpenBSD and FreeBSD. Currently supported (target)
2992 FreeBSD/amd64 x86_64-*-freebsd*
2993 FreeBSD/i386 i386-*-freebsd*
2994 OpenBSD/i386 i386-*-openbsd*
2996 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2997 are not yet supported.
2999 * New support for Matsushita MN10300 w/sim added
3000 (Work in progress). mn10300-elf.
3002 * REMOVED configurations and files
3004 VxWorks and the XDR protocol *-*-vxworks
3005 Motorola MCORE mcore-*-*
3006 National Semiconductor NS32000 ns32k-*-*
3008 * New "set print array-indexes" command
3010 After turning this setting "on", GDB prints the index of each element
3011 when displaying arrays. The default is "off" to preserve the previous
3014 * VAX floating point support
3016 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3018 * User-defined command support
3020 In addition to using $arg0..$arg9 for argument passing, it is now possible
3021 to use $argc to determine now many arguments have been passed. See the
3022 section on user-defined commands in the user manual for more information.
3024 *** Changes in GDB 6.3:
3026 * New command line option
3028 GDB now accepts -l followed by a number to set the timeout for remote
3031 * GDB works with GCC -feliminate-dwarf2-dups
3033 GDB now supports a more compact representation of DWARF-2 debug
3034 information using DW_FORM_ref_addr references. These are produced
3035 by GCC with the option -feliminate-dwarf2-dups and also by some
3036 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3037 to use -feliminate-dwarf2-dups.
3039 * Internationalization
3041 When supported by the host system, GDB will be built with
3042 internationalization (libintl). The task of marking up the sources is
3043 continued, we're looking forward to our first translation.
3047 Initial support for debugging programs compiled with the GNAT
3048 implementation of the Ada programming language has been integrated
3049 into GDB. In this release, support is limited to expression evaluation.
3051 * New native configurations
3053 GNU/Linux/m32r m32r-*-linux-gnu
3057 GDB's remote protocol now includes support for the 'p' packet. This
3058 packet is used to fetch individual registers from a remote inferior.
3060 * END-OF-LIFE registers[] compatibility module
3062 GDB's internal register infrastructure has been completely rewritten.
3063 The new infrastructure making possible the implementation of key new
3064 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3067 GDB 6.3 will be the last release to include the the registers[]
3068 compatibility module that allowed out-of-date configurations to
3069 continue to work. This change directly impacts the following
3079 powerpc bdm protocol
3081 Unless there is activity to revive these configurations, they will be
3082 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3084 * OBSOLETE configurations and files
3086 Configurations that have been declared obsolete in this release have
3087 been commented out. Unless there is activity to revive these
3088 configurations, the next release of GDB will have their sources
3089 permanently REMOVED.
3098 *** Changes in GDB 6.2.1:
3100 * MIPS `break main; run' gave an heuristic-fence-post warning
3102 When attempting to run even a simple program, a warning about
3103 heuristic-fence-post being hit would be reported. This problem has
3106 * MIPS IRIX 'long double' crashed GDB
3108 When examining a long double variable, GDB would get a segmentation
3109 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3110 IRIX long double values).
3114 A bug in the VAX stack code was causing problems with the "next"
3115 command. This problem has been fixed.
3117 *** Changes in GDB 6.2:
3119 * Fix for ``many threads''
3121 On GNU/Linux systems that use the NPTL threads library, a program
3122 rapidly creating and deleting threads would confuse GDB leading to the
3125 ptrace: No such process.
3126 thread_db_get_info: cannot get thread info: generic error
3128 This problem has been fixed.
3130 * "-async" and "-noasync" options removed.
3132 Support for the broken "-noasync" option has been removed (it caused
3135 * New ``start'' command.
3137 This command runs the program until the begining of the main procedure.
3139 * New BSD Kernel Data Access Library (libkvm) interface
3141 Using ``target kvm'' it is now possible to debug kernel core dumps and
3142 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3143 platforms. Currently supported (native-only) configurations are:
3145 FreeBSD/amd64 x86_64-*-freebsd*
3146 FreeBSD/i386 i?86-*-freebsd*
3147 NetBSD/i386 i?86-*-netbsd*
3148 NetBSD/m68k m68*-*-netbsd*
3149 NetBSD/sparc sparc-*-netbsd*
3150 OpenBSD/amd64 x86_64-*-openbsd*
3151 OpenBSD/i386 i?86-*-openbsd*
3152 OpenBSD/m68k m68*-openbsd*
3153 OpenBSD/sparc sparc-*-openbsd*
3155 * Signal trampoline code overhauled
3157 Many generic problems with GDB's signal handling code have been fixed.
3158 These include: backtraces through non-contiguous stacks; recognition
3159 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3160 call; backtrace through a signal trampoline; step into and out of
3161 signal handlers; and single-stepping in the signal trampoline.
3163 Please note that kernel bugs are a limiting factor here. These
3164 features have been shown to work on an s390 GNU/Linux system that
3165 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3167 * Cygwin support for DWARF 2 added.
3169 * New native configurations
3171 GNU/Linux/hppa hppa*-*-linux*
3172 OpenBSD/hppa hppa*-*-openbsd*
3173 OpenBSD/m68k m68*-*-openbsd*
3174 OpenBSD/m88k m88*-*-openbsd*
3175 OpenBSD/powerpc powerpc-*-openbsd*
3176 NetBSD/vax vax-*-netbsd*
3177 OpenBSD/vax vax-*-openbsd*
3179 * END-OF-LIFE frame compatibility module
3181 GDB's internal frame infrastructure has been completely rewritten.
3182 The new infrastructure making it possible to support key new features
3183 including DWARF 2 Call Frame Information. To aid in the task of
3184 migrating old configurations to this new infrastructure, a
3185 compatibility module, that allowed old configurations to continue to
3186 work, was also included.
3188 GDB 6.2 will be the last release to include this frame compatibility
3189 module. This change directly impacts the following configurations:
3199 Unless there is activity to revive these configurations, they will be
3200 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3202 * REMOVED configurations and files
3204 Sun 3, running SunOS 3 m68*-*-sunos3*
3205 Sun 3, running SunOS 4 m68*-*-sunos4*
3206 Sun 2, running SunOS 3 m68000-*-sunos3*
3207 Sun 2, running SunOS 4 m68000-*-sunos4*
3208 Motorola 680x0 running LynxOS m68*-*-lynxos*
3209 AT&T 3b1/Unix pc m68*-att-*
3210 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3211 decstation mips-dec-* mips-little-*
3212 riscos mips-*-riscos* mips-*-sysv*
3213 sonymips mips-sony-*
3214 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3216 *** Changes in GDB 6.1.1:
3218 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3220 The TUI (Text-mode User Interface) is now built as part of a default
3221 GDB configuration. It is enabled by either selecting the TUI with the
3222 command line option "-i=tui" or by running the separate "gdbtui"
3223 program. For more information on the TUI, see the manual "Debugging
3226 * Pending breakpoint support (also included in GDB 6.1)
3228 Support has been added to allow you to specify breakpoints in shared
3229 libraries that have not yet been loaded. If a breakpoint location
3230 cannot be found, and the "breakpoint pending" option is set to auto,
3231 GDB queries you if you wish to make the breakpoint pending on a future
3232 shared-library load. If and when GDB resolves the breakpoint symbol,
3233 the pending breakpoint is removed as one or more regular breakpoints
3236 Pending breakpoints are very useful for GCJ Java debugging.
3238 * Fixed ISO-C build problems
3240 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3241 non ISO-C code that stopped them being built using a more strict ISO-C
3242 compiler (e.g., IBM's C compiler).
3244 * Fixed build problem on IRIX 5
3246 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3247 wasn't able to compile compile on an IRIX 5 system.
3249 * Added execute permission to gdb/gdbserver/configure
3251 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3252 permission. This bug would cause configure to fail on a number of
3253 systems (Solaris, IRIX). Ref: server/519.
3255 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3257 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3258 has been updated to use constant array sizes.
3260 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3262 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3263 its generated DWARF Call Frame Info. This encoding was causing GDB to
3264 panic, that panic has been fixed. Ref: gdb/1628.
3266 * Fixed a problem when examining parameters in shared library code.
3268 When examining parameters in optimized shared library code generated
3269 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3270 not available''. GDB now correctly displays the variable's value.
3272 *** Changes in GDB 6.1:
3274 * Removed --with-mmalloc
3276 Support for the mmalloc memory manager has been removed, as it
3277 conflicted with the internal gdb byte cache.
3279 * Changes in AMD64 configurations
3281 The AMD64 target now includes the %cs and %ss registers. As a result
3282 the AMD64 remote protocol has changed; this affects the floating-point
3283 and SSE registers. If you rely on those registers for your debugging,
3284 you should upgrade gdbserver on the remote side.
3286 * Revised SPARC target
3288 The SPARC target has been completely revised, incorporating the
3289 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3290 support for LynxOS and SunOS 4 has been dropped. Calling functions
3291 from within GDB on operating systems with a non-executable stack
3292 (Solaris, OpenBSD) now works.
3296 GDB has a new C++ demangler which does a better job on the mangled
3297 names generated by current versions of g++. It also runs faster, so
3298 with this and other changes gdb should now start faster on large C++
3301 * DWARF 2 Location Expressions
3303 GDB support for location expressions has been extended to support function
3304 arguments and frame bases. Older versions of GDB could crash when they
3307 * C++ nested types and namespaces
3309 GDB's support for nested types and namespaces in C++ has been
3310 improved, especially if you use the DWARF 2 debugging format. (This
3311 is the default for recent versions of GCC on most platforms.)
3312 Specifically, if you have a class "Inner" defined within a class or
3313 namespace "Outer", then GDB realizes that the class's name is
3314 "Outer::Inner", not simply "Inner". This should greatly reduce the
3315 frequency of complaints about not finding RTTI symbols. In addition,
3316 if you are stopped at inside of a function defined within a namespace,
3317 GDB modifies its name lookup accordingly.
3319 * New native configurations
3321 NetBSD/amd64 x86_64-*-netbsd*
3322 OpenBSD/amd64 x86_64-*-openbsd*
3323 OpenBSD/alpha alpha*-*-openbsd*
3324 OpenBSD/sparc sparc-*-openbsd*
3325 OpenBSD/sparc64 sparc64-*-openbsd*
3327 * New debugging protocols
3329 M32R with SDI protocol m32r-*-elf*
3331 * "set prompt-escape-char" command deleted.
3333 The command "set prompt-escape-char" has been deleted. This command,
3334 and its very obscure effet on GDB's prompt, was never documented,
3335 tested, nor mentioned in the NEWS file.
3337 * OBSOLETE configurations and files
3339 Configurations that have been declared obsolete in this release have
3340 been commented out. Unless there is activity to revive these
3341 configurations, the next release of GDB will have their sources
3342 permanently REMOVED.
3344 Sun 3, running SunOS 3 m68*-*-sunos3*
3345 Sun 3, running SunOS 4 m68*-*-sunos4*
3346 Sun 2, running SunOS 3 m68000-*-sunos3*
3347 Sun 2, running SunOS 4 m68000-*-sunos4*
3348 Motorola 680x0 running LynxOS m68*-*-lynxos*
3349 AT&T 3b1/Unix pc m68*-att-*
3350 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3351 decstation mips-dec-* mips-little-*
3352 riscos mips-*-riscos* mips-*-sysv*
3353 sonymips mips-sony-*
3354 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3356 * REMOVED configurations and files
3358 SGI Irix-4.x mips-sgi-irix4 or iris4
3359 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3360 Z8000 simulator z8k-zilog-none or z8ksim
3361 Matsushita MN10200 w/simulator mn10200-*-*
3362 H8/500 simulator h8500-hitachi-hms or h8500hms
3363 HP/PA running BSD hppa*-*-bsd*
3364 HP/PA running OSF/1 hppa*-*-osf*
3365 HP/PA Pro target hppa*-*-pro*
3366 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3367 386BSD i[3456]86-*-bsd*
3368 Sequent family i[3456]86-sequent-sysv4*
3369 i[3456]86-sequent-sysv*
3370 i[3456]86-sequent-bsd*
3371 SPARC running LynxOS sparc-*-lynxos*
3372 SPARC running SunOS 4 sparc-*-sunos4*
3373 Tsqware Sparclet sparclet-*-*
3374 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3376 *** Changes in GDB 6.0:
3380 Support for debugging the Objective-C programming language has been
3381 integrated into GDB.
3383 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3385 DWARF 2's Call Frame Information makes available compiler generated
3386 information that more exactly describes the program's run-time stack.
3387 By using this information, GDB is able to provide more robust stack
3390 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3391 have been updated to use a new backtrace mechanism which includes
3392 DWARF 2 CFI support.
3396 GDB's remote protocol has been extended to include support for hosted
3397 file I/O (where the remote target uses GDB's file system). See GDB's
3398 remote protocol documentation for details.
3400 * All targets using the new architecture framework.
3402 All of GDB's targets have been updated to use the new internal
3403 architecture framework. The way is now open for future GDB releases
3404 to include cross-architecture native debugging support (i386 on amd64,
3407 * GNU/Linux's Thread Local Storage (TLS)
3409 GDB now includes support for for the GNU/Linux implementation of
3410 per-thread variables.
3412 * GNU/Linux's Native POSIX Thread Library (NPTL)
3414 GDB's thread code has been updated to work with either the new
3415 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3417 * Separate debug info.
3419 GDB, in conjunction with BINUTILS, now supports a mechanism for
3420 automatically loading debug information from a separate file. Instead
3421 of shipping full debug and non-debug versions of system libraries,
3422 system integrators can now instead ship just the stripped libraries
3423 and optional debug files.
3425 * DWARF 2 Location Expressions
3427 DWARF 2 Location Expressions allow the compiler to more completely
3428 describe the location of variables (even in optimized code) to the
3431 GDB now includes preliminary support for location expressions (support
3432 for DW_OP_piece is still missing).
3436 A number of long standing bugs that caused GDB to die while starting a
3437 Java application have been fixed. GDB's Java support is now
3438 considered "useable".
3440 * GNU/Linux support for fork, vfork, and exec.
3442 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3443 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3446 * GDB supports logging output to a file
3448 There are two new commands, "set logging" and "show logging", which can be
3449 used to capture GDB's output to a file.
3451 * The meaning of "detach" has changed for gdbserver
3453 The "detach" command will now resume the application, as documented. To
3454 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3457 * d10v, m68hc11 `regs' command deprecated
3459 The `info registers' command has been updated so that it displays the
3460 registers using a format identical to the old `regs' command.
3464 A new command, "maint set profile on/off", has been added. This command can
3465 be used to enable or disable profiling while running GDB, to profile a
3466 session or a set of commands. In addition there is a new configure switch,
3467 "--enable-profiling", which will cause GDB to be compiled with profiling
3468 data, for more informative profiling results.
3470 * Default MI syntax changed to "mi2".
3472 The default MI (machine interface) syntax, enabled by the command line
3473 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3474 "mi1", can be enabled by specifying the option "-i=mi1".
3476 Support for the original "mi0" syntax (included in GDB 5.0) has been
3479 Fix for gdb/192: removed extraneous space when displaying frame level.
3480 Fix for gdb/672: update changelist is now output in mi list format.
3481 Fix for gdb/702: a -var-assign that updates the value now shows up
3482 in a subsequent -var-update.
3484 * New native configurations.
3486 FreeBSD/amd64 x86_64-*-freebsd*
3488 * Multi-arched targets.
3490 HP/PA HPUX11 hppa*-*-hpux*
3491 Renesas M32R/D w/simulator m32r-*-elf*
3493 * OBSOLETE configurations and files
3495 Configurations that have been declared obsolete in this release have
3496 been commented out. Unless there is activity to revive these
3497 configurations, the next release of GDB will have their sources
3498 permanently REMOVED.
3500 Z8000 simulator z8k-zilog-none or z8ksim
3501 Matsushita MN10200 w/simulator mn10200-*-*
3502 H8/500 simulator h8500-hitachi-hms or h8500hms
3503 HP/PA running BSD hppa*-*-bsd*
3504 HP/PA running OSF/1 hppa*-*-osf*
3505 HP/PA Pro target hppa*-*-pro*
3506 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3507 Sequent family i[3456]86-sequent-sysv4*
3508 i[3456]86-sequent-sysv*
3509 i[3456]86-sequent-bsd*
3510 Tsqware Sparclet sparclet-*-*
3511 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3513 * REMOVED configurations and files
3516 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3517 IBM AIX PS/2 i[3456]86-*-aix
3518 i386 running Mach 3.0 i[3456]86-*-mach3*
3519 i386 running Mach i[3456]86-*-mach*
3520 i386 running OSF/1 i[3456]86-*osf1mk*
3521 HP/Apollo 68k Family m68*-apollo*-sysv*,
3523 m68*-hp-bsd*, m68*-hp-hpux*
3524 Argonaut Risc Chip (ARC) arc-*-*
3525 Mitsubishi D30V d30v-*-*
3526 Fujitsu FR30 fr30-*-elf*
3527 OS/9000 i[34]86-*-os9k
3528 I960 with MON960 i960-*-coff
3530 * MIPS $fp behavior changed
3532 The convenience variable $fp, for the MIPS, now consistently returns
3533 the address of the current frame's base. Previously, depending on the
3534 context, $fp could refer to either $sp or the current frame's base
3535 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3536 The GNU Source-Level Debugger''.
3538 *** Changes in GDB 5.3:
3540 * GNU/Linux shared library multi-threaded performance improved.
3542 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3543 `/proc', in preference to `ptrace' for memory reads. This may result
3544 in an improvement in the start-up time of multi-threaded, shared
3545 library applications when run under GDB. One GDB user writes: ``loads
3546 shared libs like mad''.
3548 * ``gdbserver'' now supports multi-threaded applications on some targets
3550 Support for debugging multi-threaded applications which use
3551 the GNU/Linux LinuxThreads package has been added for
3552 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3553 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3555 * GDB now supports C/C++ preprocessor macros.
3557 GDB now expands preprocessor macro invocations in C/C++ expressions,
3558 and provides various commands for showing macro definitions and how
3561 The new command `macro expand EXPRESSION' expands any macro
3562 invocations in expression, and shows the result.
3564 The new command `show macro MACRO-NAME' shows the definition of the
3565 macro named MACRO-NAME, and where it was defined.
3567 Most compilers don't include information about macros in the debugging
3568 information by default. In GCC 3.1, for example, you need to compile
3569 your program with the options `-gdwarf-2 -g3'. If the macro
3570 information is present in the executable, GDB will read it.
3572 * Multi-arched targets.
3574 DEC Alpha (partial) alpha*-*-*
3575 DEC VAX (partial) vax-*-*
3577 National Semiconductor NS32000 (partial) ns32k-*-*
3578 Motorola 68000 (partial) m68k-*-*
3579 Motorola MCORE mcore-*-*
3583 Fujitsu FRV architecture added by Red Hat frv*-*-*
3586 * New native configurations
3588 Alpha NetBSD alpha*-*-netbsd*
3589 SH NetBSD sh*-*-netbsdelf*
3590 MIPS NetBSD mips*-*-netbsd*
3591 UltraSPARC NetBSD sparc64-*-netbsd*
3593 * OBSOLETE configurations and files
3595 Configurations that have been declared obsolete in this release have
3596 been commented out. Unless there is activity to revive these
3597 configurations, the next release of GDB will have their sources
3598 permanently REMOVED.
3600 Mitsubishi D30V d30v-*-*
3601 OS/9000 i[34]86-*-os9k
3602 IBM AIX PS/2 i[3456]86-*-aix
3603 Fujitsu FR30 fr30-*-elf*
3604 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3605 Argonaut Risc Chip (ARC) arc-*-*
3606 i386 running Mach 3.0 i[3456]86-*-mach3*
3607 i386 running Mach i[3456]86-*-mach*
3608 i386 running OSF/1 i[3456]86-*osf1mk*
3609 HP/Apollo 68k Family m68*-apollo*-sysv*,
3611 m68*-hp-bsd*, m68*-hp-hpux*
3612 I960 with MON960 i960-*-coff
3614 * OBSOLETE languages
3616 CHILL, a Pascal like language used by telecommunications companies.
3618 * REMOVED configurations and files
3620 AMD 29k family via UDI a29k-amd-udi, udi29k
3621 A29K VxWorks a29k-*-vxworks
3622 AMD 29000 embedded, using EBMON a29k-none-none
3623 AMD 29000 embedded with COFF a29k-none-coff
3624 AMD 29000 embedded with a.out a29k-none-aout
3626 testsuite/gdb.hp/gdb.threads-hp/ directory
3628 * New command "set max-user-call-depth <nnn>"
3630 This command allows the user to limit the call depth of user-defined
3631 commands. The default is 1024.
3633 * Changes in FreeBSD/i386 native debugging.
3635 Support for the "generate-core-file" has been added.
3637 * New commands "dump", "append", and "restore".
3639 These commands allow data to be copied from target memory
3640 to a bfd-format or binary file (dump and append), and back
3641 from a file into memory (restore).
3643 * Improved "next/step" support on multi-processor Alpha Tru64.
3645 The previous single-step mechanism could cause unpredictable problems,
3646 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3647 of a software single-step mechanism prevents this.
3649 *** Changes in GDB 5.2.1:
3657 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3658 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3659 Fix, by Joel Brobecker imported from mainline.
3661 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3662 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3663 Fix, by Fred Fish, imported from mainline.
3665 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3666 Surprisingly enough, it works now.
3667 By Michal Ludvig, imported from mainline.
3669 i386 hardware watchpoint support:
3670 avoid misses on second run for some targets.
3671 By Pierre Muller, imported from mainline.
3673 *** Changes in GDB 5.2:
3675 * New command "set trust-readonly-sections on[off]".
3677 This command is a hint that tells gdb that read-only sections
3678 really are read-only (ie. that their contents will not change).
3679 In this mode, gdb will go to the object file rather than the
3680 target to read memory from read-only sections (such as ".text").
3681 This can be a significant performance improvement on some
3682 (notably embedded) targets.
3684 * New command "generate-core-file" (or "gcore").
3686 This new gdb command allows the user to drop a core file of the child
3687 process state at any time. So far it's been implemented only for
3688 GNU/Linux and Solaris, but should be relatively easily ported to other
3689 hosts. Argument is core file name (defaults to core.<pid>).
3691 * New command line option
3693 GDB now accepts --pid or -p followed by a process id.
3695 * Change in command line behavior -- corefiles vs. process ids.
3697 There is a subtle behavior in the way in which GDB handles
3698 command line arguments. The first non-flag argument is always
3699 a program to debug, but the second non-flag argument may either
3700 be a corefile or a process id. Previously, GDB would attempt to
3701 open the second argument as a corefile, and if that failed, would
3702 issue a superfluous error message and then attempt to attach it as
3703 a process. Now, if the second argument begins with a non-digit,
3704 it will be treated as a corefile. If it begins with a digit,
3705 GDB will attempt to attach it as a process, and if no such process
3706 is found, will then attempt to open it as a corefile.
3708 * Changes in ARM configurations.
3710 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3711 configuration is fully multi-arch.
3713 * New native configurations
3715 ARM NetBSD arm*-*-netbsd*
3716 x86 OpenBSD i[3456]86-*-openbsd*
3717 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3718 Sparc64 running FreeBSD sparc64-*-freebsd*
3722 Sanyo XStormy16 xstormy16-elf
3724 * OBSOLETE configurations and files
3726 Configurations that have been declared obsolete in this release have
3727 been commented out. Unless there is activity to revive these
3728 configurations, the next release of GDB will have their sources
3729 permanently REMOVED.
3731 AMD 29k family via UDI a29k-amd-udi, udi29k
3732 A29K VxWorks a29k-*-vxworks
3733 AMD 29000 embedded, using EBMON a29k-none-none
3734 AMD 29000 embedded with COFF a29k-none-coff
3735 AMD 29000 embedded with a.out a29k-none-aout
3737 testsuite/gdb.hp/gdb.threads-hp/ directory
3739 * REMOVED configurations and files
3741 TI TMS320C80 tic80-*-*
3743 PowerPC Solaris powerpcle-*-solaris*
3744 PowerPC Windows NT powerpcle-*-cygwin32
3745 PowerPC Netware powerpc-*-netware*
3746 Harris/CXUX m88k m88*-harris-cxux*
3747 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3748 ns32k-utek-sysv* ns32k-utek-*
3749 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3750 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3751 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3752 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3753 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3755 * Changes to command line processing
3757 The new `--args' feature can be used to specify command-line arguments
3758 for the inferior from gdb's command line.
3760 * Changes to key bindings
3762 There is a new `operate-and-get-next' function bound to `C-o'.
3764 *** Changes in GDB 5.1.1
3766 Fix compile problem on DJGPP.
3768 Fix a problem with floating-point registers on the i386 being
3771 Fix to stop GDB crashing on .debug_str debug info.
3773 Numerous documentation fixes.
3775 Numerous testsuite fixes.
3777 *** Changes in GDB 5.1:
3779 * New native configurations
3781 Alpha FreeBSD alpha*-*-freebsd*
3782 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3783 MIPS GNU/Linux mips*-*-linux*
3784 MIPS SGI Irix 6.x mips*-sgi-irix6*
3785 ia64 AIX ia64-*-aix*
3786 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3790 Motorola 68HC11 and 68HC12 m68hc11-elf
3792 UltraSparc running GNU/Linux sparc64-*-linux*
3794 * OBSOLETE configurations and files
3796 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3797 Harris/CXUX m88k m88*-harris-cxux*
3798 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3799 ns32k-utek-sysv* ns32k-utek-*
3800 TI TMS320C80 tic80-*-*
3802 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3803 PowerPC Solaris powerpcle-*-solaris*
3804 PowerPC Windows NT powerpcle-*-cygwin32
3805 PowerPC Netware powerpc-*-netware*
3806 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3807 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3808 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3809 Apple Macintosh (MPW) host N/A
3811 stuff.c (Program to stuff files into a specially prepared space in kdb)
3812 kdb-start.c (Main loop for the standalone kernel debugger)
3814 Configurations that have been declared obsolete in this release have
3815 been commented out. Unless there is activity to revive these
3816 configurations, the next release of GDB will have their sources
3817 permanently REMOVED.
3819 * REMOVED configurations and files
3821 Altos 3068 m68*-altos-*
3822 Convex c1-*-*, c2-*-*
3824 ARM RISCix arm-*-* (as host)
3828 * GDB has been converted to ISO C.
3830 GDB's source code has been converted to ISO C. In particular, the
3831 sources are fully protoized, and rely on standard headers being
3836 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3838 * The MI enabled by default.
3840 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3841 revised and enabled by default. Packages which use GDB as a debugging
3842 engine behind a UI or another front end are encouraged to switch to
3843 using the GDB/MI interface, instead of the old annotations interface
3844 which is now deprecated.
3846 * Support for debugging Pascal programs.
3848 GDB now includes support for debugging Pascal programs. The following
3849 main features are supported:
3851 - Pascal-specific data types such as sets;
3853 - automatic recognition of Pascal sources based on file-name
3856 - Pascal-style display of data types, variables, and functions;
3858 - a Pascal expression parser.
3860 However, some important features are not yet supported.
3862 - Pascal string operations are not supported at all;
3864 - there are some problems with boolean types;
3866 - Pascal type hexadecimal constants are not supported
3867 because they conflict with the internal variables format;
3869 - support for Pascal objects and classes is not full yet;
3871 - unlike Pascal, GDB is case-sensitive for symbol names.
3873 * Changes in completion.
3875 Commands such as `shell', `run' and `set args', which pass arguments
3876 to inferior programs, now complete on file names, similar to what
3877 users expect at the shell prompt.
3879 Commands which accept locations, such as `disassemble', `print',
3880 `breakpoint', `until', etc. now complete on filenames as well as
3881 program symbols. Thus, if you type "break foob TAB", and the source
3882 files linked into the programs include `foobar.c', that file name will
3883 be one of the candidates for completion. However, file names are not
3884 considered for completion after you typed a colon that delimits a file
3885 name from a name of a function in that file, as in "break foo.c:bar".
3887 `set demangle-style' completes on available demangling styles.
3889 * New platform-independent commands:
3891 It is now possible to define a post-hook for a command as well as a
3892 hook that runs before the command. For more details, see the
3893 documentation of `hookpost' in the GDB manual.
3895 * Changes in GNU/Linux native debugging.
3897 Support for debugging multi-threaded programs has been completely
3898 revised for all platforms except m68k and sparc. You can now debug as
3899 many threads as your system allows you to have.
3901 Attach/detach is supported for multi-threaded programs.
3903 Support for SSE registers was added for x86. This doesn't work for
3904 multi-threaded programs though.
3906 * Changes in MIPS configurations.
3908 Multi-arch support is enabled for all MIPS configurations.
3910 GDB can now be built as native debugger on SGI Irix 6.x systems for
3911 debugging n32 executables. (Debugging 64-bit executables is not yet
3914 * Unified support for hardware watchpoints in all x86 configurations.
3916 Most (if not all) native x86 configurations support hardware-assisted
3917 breakpoints and watchpoints in a unified manner. This support
3918 implements debug register sharing between watchpoints, which allows to
3919 put a virtually infinite number of watchpoints on the same address,
3920 and also supports watching regions up to 16 bytes with several debug
3923 The new maintenance command `maintenance show-debug-regs' toggles
3924 debugging print-outs in functions that insert, remove, and test
3925 watchpoints and hardware breakpoints.
3927 * Changes in the DJGPP native configuration.
3929 New command ``info dos sysinfo'' displays assorted information about
3930 the CPU, OS, memory, and DPMI server.
3932 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3933 display information about segment descriptors stored in GDT, LDT, and
3936 New commands ``info dos pde'' and ``info dos pte'' display entries
3937 from Page Directory and Page Tables (for now works with CWSDPMI only).
3938 New command ``info dos address-pte'' displays the Page Table entry for
3939 a given linear address.
3941 GDB can now pass command lines longer than 126 characters to the
3942 program being debugged (requires an update to the libdbg.a library
3943 which is part of the DJGPP development kit).
3945 DWARF2 debug info is now supported.
3947 It is now possible to `step' and `next' through calls to `longjmp'.
3949 * Changes in documentation.
3951 All GDB documentation was converted to GFDL, the GNU Free
3952 Documentation License.
3954 Tracepoints-related commands are now fully documented in the GDB
3957 TUI, the Text-mode User Interface, is now documented in the manual.
3959 Tracepoints-related commands are now fully documented in the GDB
3962 The "GDB Internals" manual now has an index. It also includes
3963 documentation of `ui_out' functions, GDB coding standards, x86
3964 hardware watchpoints, and memory region attributes.
3966 * GDB's version number moved to ``version.in''
3968 The Makefile variable VERSION has been replaced by the file
3969 ``version.in''. People creating GDB distributions should update the
3970 contents of this file.
3974 GUD support is now a standard part of the EMACS distribution.
3976 *** Changes in GDB 5.0:
3978 * Improved support for debugging FP programs on x86 targets
3980 Unified and much-improved support for debugging floating-point
3981 programs on all x86 targets. In particular, ``info float'' now
3982 displays the FP registers in the same format on all x86 targets, with
3983 greater level of detail.
3985 * Improvements and bugfixes in hardware-assisted watchpoints
3987 It is now possible to watch array elements, struct members, and
3988 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3989 on x86 targets no longer erroneously trigger when the address is
3992 * Improvements in the native DJGPP version of GDB
3994 The distribution now includes all the scripts and auxiliary files
3995 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3996 machines ``out of the box''.
3998 The DJGPP version can now debug programs that use signals. It is
3999 possible to catch signals that happened in the debuggee, deliver
4000 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4001 would kill the program being debugged.) Programs that hook hardware
4002 interrupts (keyboard, timer, etc.) can also be debugged.
4004 It is now possible to debug DJGPP programs that redirect their
4005 standard handles or switch them to raw (as opposed to cooked) mode, or
4006 even close them. The command ``run < foo > bar'' works as expected,
4007 and ``info terminal'' reports useful information about the debuggee's
4008 terminal, including raw/cooked mode, redirection, etc.
4010 The DJGPP version now uses termios functions for console I/O, which
4011 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4014 DOS-style file names with drive letters are now fully supported by
4017 It is now possible to debug DJGPP programs that switch their working
4018 directory. It is also possible to rerun the debuggee any number of
4019 times without restarting GDB; thus, you can use the same setup,
4020 breakpoints, etc. for many debugging sessions.
4022 * New native configurations
4024 ARM GNU/Linux arm*-*-linux*
4025 PowerPC GNU/Linux powerpc-*-linux*
4029 Motorola MCore mcore-*-*
4030 x86 VxWorks i[3456]86-*-vxworks*
4031 PowerPC VxWorks powerpc-*-vxworks*
4032 TI TMS320C80 tic80-*-*
4034 * OBSOLETE configurations
4036 Altos 3068 m68*-altos-*
4037 Convex c1-*-*, c2-*-*
4039 ARM RISCix arm-*-* (as host)
4042 Configurations that have been declared obsolete will be commented out,
4043 but the code will be left in place. If there is no activity to revive
4044 these configurations before the next release of GDB, the sources will
4045 be permanently REMOVED.
4047 * Gould support removed
4049 Support for the Gould PowerNode and NP1 has been removed.
4051 * New features for SVR4
4053 On SVR4 native platforms (such as Solaris), if you attach to a process
4054 without first loading a symbol file, GDB will now attempt to locate and
4055 load symbols from the running process's executable file.
4057 * Many C++ enhancements
4059 C++ support has been greatly improved. Overload resolution now works properly
4060 in almost all cases. RTTI support is on the way.
4062 * Remote targets can connect to a sub-program
4064 A popen(3) style serial-device has been added. This device starts a
4065 sub-process (such as a stand-alone simulator) and then communicates
4066 with that. The sub-program to run is specified using the syntax
4067 ``|<program> <args>'' vis:
4069 (gdb) set remotedebug 1
4070 (gdb) target extended-remote |mn10300-elf-sim program-args
4072 * MIPS 64 remote protocol
4074 A long standing bug in the mips64 remote protocol where by GDB
4075 expected certain 32 bit registers (ex SR) to be transfered as 32
4076 instead of 64 bits has been fixed.
4078 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4079 added to provide backward compatibility with older versions of GDB.
4081 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4083 The command ``set remotebinarydownload'' command has been replaced by
4084 ``set remote X-packet''. Other commands in ``set remote'' family
4085 include ``set remote P-packet''.
4087 * Breakpoint commands accept ranges.
4089 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4090 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4091 ``tracepoint passcount'' also accepts a range of tracepoints.
4093 * ``apropos'' command added.
4095 The ``apropos'' command searches through command names and
4096 documentation strings, printing out matches, making it much easier to
4097 try to find a command that does what you are looking for.
4101 A new machine oriented interface (MI) has been added to GDB. This
4102 interface is designed for debug environments running GDB as a separate
4103 process. This is part of the long term libGDB project. See the
4104 "GDB/MI" chapter of the GDB manual for further information. It can be
4105 enabled by configuring with:
4107 .../configure --enable-gdbmi
4109 *** Changes in GDB-4.18:
4111 * New native configurations
4113 HP-UX 10.20 hppa*-*-hpux10.20
4114 HP-UX 11.x hppa*-*-hpux11.0*
4115 M68K GNU/Linux m68*-*-linux*
4119 Fujitsu FR30 fr30-*-elf*
4120 Intel StrongARM strongarm-*-*
4121 Mitsubishi D30V d30v-*-*
4123 * OBSOLETE configurations
4125 Gould PowerNode, NP1 np1-*-*, pn-*-*
4127 Configurations that have been declared obsolete will be commented out,
4128 but the code will be left in place. If there is no activity to revive
4129 these configurations before the next release of GDB, the sources will
4130 be permanently REMOVED.
4134 As a compatibility experiment, GDB's source files buildsym.h and
4135 buildsym.c have been converted to pure standard C, no longer
4136 containing any K&R compatibility code. We believe that all systems in
4137 use today either come with a standard C compiler, or have a GCC port
4138 available. If this is not true, please report the affected
4139 configuration to bug-gdb@gnu.org immediately. See the README file for
4140 information about getting a standard C compiler if you don't have one
4145 GDB now uses readline 2.2.
4147 * set extension-language
4149 You can now control the mapping between filename extensions and source
4150 languages by using the `set extension-language' command. For instance,
4151 you can ask GDB to treat .c files as C++ by saying
4152 set extension-language .c c++
4153 The command `info extensions' lists all of the recognized extensions
4154 and their associated languages.
4156 * Setting processor type for PowerPC and RS/6000
4158 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4159 you can use the `set processor' command to specify what variant of the
4160 PowerPC family you are debugging. The command
4164 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4165 following PowerPC and RS6000 variants:
4167 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4168 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4170 403GC IBM PowerPC 403GC
4171 505 Motorola PowerPC 505
4172 860 Motorola PowerPC 860 or 850
4173 601 Motorola PowerPC 601
4174 602 Motorola PowerPC 602
4175 603 Motorola/IBM PowerPC 603 or 603e
4176 604 Motorola PowerPC 604 or 604e
4177 750 Motorola/IBM PowerPC 750 or 750
4179 At the moment, this command just tells GDB what to name the
4180 special-purpose processor registers. Since almost all the affected
4181 registers are inaccessible to user-level programs, this command is
4182 only useful for remote debugging in its present form.
4186 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4187 more extensive support for HP-UX. Added features include shared
4188 library support, kernel threads and hardware watchpoints for 11.00,
4189 support for HP's ANSI C and C++ compilers, and a compatibility mode
4190 for xdb and dbx commands.
4194 HP's donation includes the new concept of catchpoints, which is a
4195 generalization of the old catch command. On HP-UX, it is now possible
4196 to catch exec, fork, and vfork, as well as library loading.
4198 This means that the existing catch command has changed; its first
4199 argument now specifies the type of catch to be set up. See the
4200 output of "help catch" for a list of catchpoint types.
4202 * Debugging across forks
4204 On HP-UX, you can choose which process to debug when a fork() happens
4209 HP has donated a curses-based terminal user interface (TUI). To get
4210 it, build with --enable-tui. Although this can be enabled for any
4211 configuration, at present it only works for native HP debugging.
4213 * GDB remote protocol additions
4215 A new protocol packet 'X' that writes binary data is now available.
4216 Default behavior is to try 'X', then drop back to 'M' if the stub
4217 fails to respond. The settable variable `remotebinarydownload'
4218 allows explicit control over the use of 'X'.
4220 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4221 full 64-bit address. The command
4223 set remoteaddresssize 32
4225 can be used to revert to the old behaviour. For existing remote stubs
4226 the change should not be noticed, as the additional address information
4229 In order to assist in debugging stubs, you may use the maintenance
4230 command `packet' to send any text string to the stub. For instance,
4232 maint packet heythere
4234 sends the packet "$heythere#<checksum>". Note that it is very easy to
4235 disrupt a debugging session by sending the wrong packet at the wrong
4238 The compare-sections command allows you to compare section data on the
4239 target to what is in the executable file without uploading or
4240 downloading, by comparing CRC checksums.
4242 * Tracing can collect general expressions
4244 You may now collect general expressions at tracepoints. This requires
4245 further additions to the target-side stub; see tracepoint.c and
4246 doc/agentexpr.texi for further details.
4248 * mask-address variable for Mips
4250 For Mips targets, you may control the zeroing of the upper 32 bits of
4251 a 64-bit address by entering `set mask-address on'. This is mainly
4252 of interest to users of embedded R4xxx and R5xxx processors.
4254 * Higher serial baud rates
4256 GDB's serial code now allows you to specify baud rates 57600, 115200,
4257 230400, and 460800 baud. (Note that your host system may not be able
4258 to achieve all of these rates.)
4262 The i960 configuration now includes an initial implementation of a
4263 builtin simulator, contributed by Jim Wilson.
4266 *** Changes in GDB-4.17:
4268 * New native configurations
4270 Alpha GNU/Linux alpha*-*-linux*
4271 Unixware 2.x i[3456]86-unixware2*
4272 Irix 6.x mips*-sgi-irix6*
4273 PowerPC GNU/Linux powerpc-*-linux*
4274 PowerPC Solaris powerpcle-*-solaris*
4275 Sparc GNU/Linux sparc-*-linux*
4276 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4280 Argonaut Risc Chip (ARC) arc-*-*
4281 Hitachi H8/300S h8300*-*-*
4282 Matsushita MN10200 w/simulator mn10200-*-*
4283 Matsushita MN10300 w/simulator mn10300-*-*
4284 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4285 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4286 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4287 Mitsubishi D10V w/simulator d10v-*-*
4288 Mitsubishi M32R/D w/simulator m32r-*-elf*
4289 Tsqware Sparclet sparclet-*-*
4290 NEC V850 w/simulator v850-*-*
4292 * New debugging protocols
4294 ARM with RDI protocol arm*-*-*
4295 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4296 DDB and LSI variants of PMON protocol mips*-*-*
4297 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4298 PowerPC with SDS protocol powerpc{,le}-*-eabi
4299 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4303 All configurations can now understand and use the DWARF 2 debugging
4304 format. The choice is automatic, if the symbol file contains DWARF 2
4309 GDB now includes basic Java language support. This support is
4310 only useful with Java compilers that produce native machine code.
4312 * solib-absolute-prefix and solib-search-path
4314 For SunOS and SVR4 shared libraries, you may now set the prefix for
4315 loading absolute shared library symbol files, and the search path for
4316 locating non-absolute shared library symbol files.
4318 * Live range splitting
4320 GDB can now effectively debug code for which GCC has performed live
4321 range splitting as part of its optimization. See gdb/doc/LRS for
4322 more details on the expected format of the stabs information.
4326 GDB's support for the GNU Hurd, including thread debugging, has been
4327 updated to work with current versions of the Hurd.
4331 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4332 instruction set. ARM GDB automatically detects when Thumb
4333 instructions are in use, and adjusts disassembly and backtracing
4338 GDB's MIPS target configurations now handle the MIP16 16-bit
4343 GDB now includes support for overlays; if an executable has been
4344 linked such that multiple sections are based at the same address, GDB
4345 will decide which section to use for symbolic info. You can choose to
4346 control the decision manually, using overlay commands, or implement
4347 additional target-side support and use "overlay load-target" to bring
4348 in the overlay mapping. Do "help overlay" for more detail.
4352 The command "info symbol <address>" displays information about
4353 the symbol at the specified address.
4357 The standard remote protocol now includes an extension that allows
4358 asynchronous collection and display of trace data. This requires
4359 extensive support in the target-side debugging stub. Tracing mode
4360 includes a new interaction mode in GDB and new commands: see the
4361 file tracepoint.c for more details.
4365 Configurations for embedded MIPS now include a simulator contributed
4366 by Cygnus Solutions. The simulator supports the instruction sets
4367 of most MIPS variants.
4371 Sparc configurations may now include the ERC32 simulator contributed
4372 by the European Space Agency. The simulator is not built into
4373 Sparc targets by default; configure with --enable-sim to include it.
4377 For target configurations that may include multiple variants of a
4378 basic architecture (such as MIPS and SH), you may now set the
4379 architecture explicitly. "set arch" sets, "info arch" lists
4380 the possible architectures.
4382 *** Changes in GDB-4.16:
4384 * New native configurations
4386 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4387 M68K NetBSD m68k-*-netbsd*
4388 PowerPC AIX 4.x powerpc-*-aix*
4389 PowerPC MacOS powerpc-*-macos*
4390 PowerPC Windows NT powerpcle-*-cygwin32
4391 RS/6000 AIX 4.x rs6000-*-aix4*
4395 ARM with RDP protocol arm-*-*
4396 I960 with MON960 i960-*-coff
4397 MIPS VxWorks mips*-*-vxworks*
4398 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4399 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4401 Matra Sparclet sparclet-*-*
4405 The powerpc-eabi configuration now includes the PSIM simulator,
4406 contributed by Andrew Cagney, with assistance from Mike Meissner.
4407 PSIM is a very elaborate model of the PowerPC, including not only
4408 basic instruction set execution, but also details of execution unit
4409 performance and I/O hardware. See sim/ppc/README for more details.
4413 GDB now works with Solaris 2.5.
4415 * Windows 95/NT native
4417 GDB will now work as a native debugger on Windows 95 and Windows NT.
4418 To build it from source, you must use the "gnu-win32" environment,
4419 which uses a DLL to emulate enough of Unix to run the GNU tools.
4420 Further information, binaries, and sources are available at
4421 ftp.cygnus.com, under pub/gnu-win32.
4423 * dont-repeat command
4425 If a user-defined command includes the command `dont-repeat', then the
4426 command will not be repeated if the user just types return. This is
4427 useful if the command is time-consuming to run, so that accidental
4428 extra keystrokes don't run the same command many times.
4430 * Send break instead of ^C
4432 The standard remote protocol now includes an option to send a break
4433 rather than a ^C to the target in order to interrupt it. By default,
4434 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4436 * Remote protocol timeout
4438 The standard remote protocol includes a new variable `remotetimeout'
4439 that allows you to set the number of seconds before GDB gives up trying
4440 to read from the target. The default value is 2.
4442 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4444 By default GDB will automatically keep track of objects as they are
4445 loaded and unloaded by the dynamic linker. By using the command `set
4446 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4447 when shared library events occur, thus allowing you to set breakpoints
4448 in shared libraries which are explicitly loaded by the inferior.
4450 Note this feature does not work on hpux8. On hpux9 you must link
4451 /usr/lib/end.o into your program. This feature should work
4452 automatically on hpux10.
4454 * Irix 5.x hardware watchpoint support
4456 Irix 5 configurations now support the use of hardware watchpoints.
4458 * Mips protocol "SYN garbage limit"
4460 When debugging a Mips target using the `target mips' protocol, you
4461 may set the number of characters that GDB will ignore by setting
4462 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4463 every character. The default value is 1050.
4465 * Recording and replaying remote debug sessions
4467 If you set `remotelogfile' to the name of a file, gdb will write to it
4468 a recording of a remote debug session. This recording may then be
4469 replayed back to gdb using "gdbreplay". See gdbserver/README for
4470 details. This is useful when you have a problem with GDB while doing
4471 remote debugging; you can make a recording of the session and send it
4472 to someone else, who can then recreate the problem.
4474 * Speedups for remote debugging
4476 GDB includes speedups for downloading and stepping MIPS systems using
4477 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4478 and more efficient S-record downloading.
4480 * Memory use reductions and statistics collection
4482 GDB now uses less memory and reports statistics about memory usage.
4483 Try the `maint print statistics' command, for example.
4485 *** Changes in GDB-4.15:
4487 * Psymtabs for XCOFF
4489 The symbol reader for AIX GDB now uses partial symbol tables. This
4490 can greatly improve startup time, especially for large executables.
4492 * Remote targets use caching
4494 Remote targets now use a data cache to speed up communication with the
4495 remote side. The data cache could lead to incorrect results because
4496 it doesn't know about volatile variables, thus making it impossible to
4497 debug targets which use memory mapped I/O devices. `set remotecache
4498 off' turns the the data cache off.
4500 * Remote targets may have threads
4502 The standard remote protocol now includes support for multiple threads
4503 in the target system, using new protocol commands 'H' and 'T'. See
4504 gdb/remote.c for details.
4508 If GDB is configured with `--enable-netrom', then it will include
4509 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4510 acts as though it is a bank of ROM on the target board, but you can
4511 write into it over the network. GDB's support consists only of
4512 support for fast loading into the emulated ROM; to debug, you must use
4513 another protocol, such as standard remote protocol. The usual
4514 sequence is something like
4516 target nrom <netrom-hostname>
4518 target remote <netrom-hostname>:1235
4522 GDB now includes support for the Apple Macintosh, as a host only. It
4523 may be run as either an MPW tool or as a standalone application, and
4524 it can debug through the serial port. All the usual GDB commands are
4525 available, but to the target command, you must supply "serial" as the
4526 device type instead of "/dev/ttyXX". See mpw-README in the main
4527 directory for more information on how to build. The MPW configuration
4528 scripts */mpw-config.in support only a few targets, and only the
4529 mips-idt-ecoff target has been tested.
4533 GDB configuration now uses autoconf. This is not user-visible,
4534 but does simplify configuration and building.
4538 GDB now supports hpux10.
4540 *** Changes in GDB-4.14:
4542 * New native configurations
4544 x86 FreeBSD i[345]86-*-freebsd
4545 x86 NetBSD i[345]86-*-netbsd
4546 NS32k NetBSD ns32k-*-netbsd
4547 Sparc NetBSD sparc-*-netbsd
4551 A29K VxWorks a29k-*-vxworks
4552 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4553 CPU32 EST-300 emulator m68*-*-est*
4554 PowerPC ELF powerpc-*-elf
4557 * Alpha OSF/1 support for procfs
4559 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4560 possible to attach to running processes. As the mounting of the /proc
4561 filesystem is optional on the Alpha, GDB automatically determines
4562 the availability of /proc during startup. This can lead to problems
4563 if /proc is unmounted after GDB has been started.
4565 * Arguments to user-defined commands
4567 User commands may accept up to 10 arguments separated by whitespace.
4568 Arguments are accessed within the user command via $arg0..$arg9. A
4571 print $arg0 + $arg1 + $arg2
4573 To execute the command use:
4576 Defines the command "adder" which prints the sum of its three arguments.
4577 Note the arguments are text substitutions, so they may reference variables,
4578 use complex expressions, or even perform inferior function calls.
4580 * New `if' and `while' commands
4582 This makes it possible to write more sophisticated user-defined
4583 commands. Both commands take a single argument, which is the
4584 expression to evaluate, and must be followed by the commands to
4585 execute, one per line, if the expression is nonzero, the list being
4586 terminated by the word `end'. The `if' command list may include an
4587 `else' word, which causes the following commands to be executed only
4588 if the expression is zero.
4590 * Fortran source language mode
4592 GDB now includes partial support for Fortran 77. It will recognize
4593 Fortran programs and can evaluate a subset of Fortran expressions, but
4594 variables and functions may not be handled correctly. GDB will work
4595 with G77, but does not yet know much about symbols emitted by other
4598 * Better HPUX support
4600 Most debugging facilities now work on dynamic executables for HPPAs
4601 running hpux9 or later. You can attach to running dynamically linked
4602 processes, but by default the dynamic libraries will be read-only, so
4603 for instance you won't be able to put breakpoints in them. To change
4604 that behavior do the following before running the program:
4610 This will cause the libraries to be mapped private and read-write.
4611 To revert to the normal behavior, do this:
4617 You cannot set breakpoints or examine data in the library until after
4618 the library is loaded if the function/data symbols do not have
4621 GDB can now also read debug symbols produced by the HP C compiler on
4622 HPPAs (sorry, no C++, Fortran or 68k support).
4624 * Target byte order now dynamically selectable
4626 You can choose which byte order to use with a target system, via the
4627 commands "set endian big" and "set endian little", and you can see the
4628 current setting by using "show endian". You can also give the command
4629 "set endian auto", in which case GDB will use the byte order
4630 associated with the executable. Currently, only embedded MIPS
4631 configurations support dynamic selection of target byte order.
4633 * New DOS host serial code
4635 This version uses DPMI interrupts to handle buffered I/O, so you
4636 no longer need to run asynctsr when debugging boards connected to
4639 *** Changes in GDB-4.13:
4641 * New "complete" command
4643 This lists all the possible completions for the rest of the line, if it
4644 were to be given as a command itself. This is intended for use by emacs.
4646 * Trailing space optional in prompt
4648 "set prompt" no longer adds a space for you after the prompt you set. This
4649 allows you to set a prompt which ends in a space or one that does not.
4651 * Breakpoint hit counts
4653 "info break" now displays a count of the number of times the breakpoint
4654 has been hit. This is especially useful in conjunction with "ignore"; you
4655 can ignore a large number of breakpoint hits, look at the breakpoint info
4656 to see how many times the breakpoint was hit, then run again, ignoring one
4657 less than that number, and this will get you quickly to the last hit of
4660 * Ability to stop printing at NULL character
4662 "set print null-stop" will cause GDB to stop printing the characters of
4663 an array when the first NULL is encountered. This is useful when large
4664 arrays actually contain only short strings.
4666 * Shared library breakpoints
4668 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4669 breakpoints in shared libraries before the executable is run.
4671 * Hardware watchpoints
4673 There is a new hardware breakpoint for the watch command for sparclite
4674 targets. See gdb/sparclite/hw_breakpoint.note.
4676 Hardware watchpoints are also now supported under GNU/Linux.
4680 Annotations have been added. These are for use with graphical interfaces,
4681 and are still experimental. Currently only gdba.el uses these.
4683 * Improved Irix 5 support
4685 GDB now works properly with Irix 5.2.
4687 * Improved HPPA support
4689 GDB now works properly with the latest GCC and GAS.
4691 * New native configurations
4693 Sequent PTX4 i[34]86-sequent-ptx4
4694 HPPA running OSF/1 hppa*-*-osf*
4695 Atari TT running SVR4 m68*-*-sysv4*
4696 RS/6000 LynxOS rs6000-*-lynxos*
4700 OS/9000 i[34]86-*-os9k
4701 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4704 * Hitachi SH7000 and E7000-PC ICE support
4706 There is now support for communicating with the Hitachi E7000-PC ICE.
4707 This is available automatically when GDB is configured for the SH.
4711 As usual, a variety of small fixes and improvements, both generic
4712 and configuration-specific. See the ChangeLog for more detail.
4714 *** Changes in GDB-4.12:
4716 * Irix 5 is now supported
4720 GDB-4.12 on the HPPA has a number of changes which make it unable
4721 to debug the output from the currently released versions of GCC and
4722 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4723 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4724 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4727 *** Changes in GDB-4.11:
4729 * User visible changes:
4733 The "set remotedebug" option is now consistent between the mips remote
4734 target, remote targets using the gdb-specific protocol, UDI (AMD's
4735 debug protocol for the 29k) and the 88k bug monitor. It is now an
4736 integer specifying a debug level (normally 0 or 1, but 2 means more
4737 debugging info for the mips target).
4739 * DEC Alpha native support
4741 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4742 debug info, but GDB works fairly well with the DEC compiler and should
4743 work with a future GCC release. See the README file for a few
4744 Alpha-specific notes.
4746 * Preliminary thread implementation
4748 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4750 * LynxOS native and target support for 386
4752 This release has been hosted on LynxOS 2.2, and also can be configured
4753 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4756 * Improvements in C++ mangling/demangling.
4758 This release has much better g++ debugging, specifically in name
4759 mangling/demangling, virtual function calls, print virtual table,
4760 call methods, ...etc.
4762 *** Changes in GDB-4.10:
4764 * User visible changes:
4766 Remote debugging using the GDB-specific (`target remote') protocol now
4767 supports the `load' command. This is only useful if you have some
4768 other way of getting the stub to the target system, and you can put it
4769 somewhere in memory where it won't get clobbered by the download.
4771 Filename completion now works.
4773 When run under emacs mode, the "info line" command now causes the
4774 arrow to point to the line specified. Also, "info line" prints
4775 addresses in symbolic form (as well as hex).
4777 All vxworks based targets now support a user settable option, called
4778 vxworks-timeout. This option represents the number of seconds gdb
4779 should wait for responses to rpc's. You might want to use this if
4780 your vxworks target is, perhaps, a slow software simulator or happens
4781 to be on the far side of a thin network line.
4785 This release contains support for using a DEC alpha as a GDB host for
4786 cross debugging. Native alpha debugging is not supported yet.
4789 *** Changes in GDB-4.9:
4793 This is the first GDB release which is accompanied by a matching testsuite.
4794 The testsuite requires installation of dejagnu, which should be available
4795 via ftp from most sites that carry GNU software.
4799 'Cfront' style demangling has had its name changed to 'ARM' style, to
4800 emphasize that it was written from the specifications in the C++ Annotated
4801 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4802 disclaimers, it still generated too much confusion with users attempting to
4803 use gdb with AT&T cfront.
4807 GDB now uses a standard remote interface to a simulator library.
4808 So far, the library contains simulators for the Zilog Z8001/2, the
4809 Hitachi H8/300, H8/500 and Super-H.
4811 * New targets supported
4813 H8/300 simulator h8300-hitachi-hms or h8300hms
4814 H8/500 simulator h8500-hitachi-hms or h8500hms
4815 SH simulator sh-hitachi-hms or sh
4816 Z8000 simulator z8k-zilog-none or z8ksim
4817 IDT MIPS board over serial line mips-idt-ecoff
4819 Cross-debugging to GO32 targets is supported. It requires a custom
4820 version of the i386-stub.c module which is integrated with the
4821 GO32 memory extender.
4823 * New remote protocols
4825 MIPS remote debugging protocol.
4827 * New source languages supported
4829 This version includes preliminary support for Chill, a Pascal like language
4830 used by telecommunications companies. Chill support is also being integrated
4831 into the GNU compiler, but we don't know when it will be publically available.
4834 *** Changes in GDB-4.8:
4836 * HP Precision Architecture supported
4838 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4839 version of this support was available as a set of patches from the
4840 University of Utah. GDB does not support debugging of programs
4841 compiled with the HP compiler, because HP will not document their file
4842 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4843 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4845 Many problems in the preliminary version have been fixed.
4847 * Faster and better demangling
4849 We have improved template demangling and fixed numerous bugs in the GNU style
4850 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4851 character types (wchar_t) are now supported. Demangling of each symbol is now
4852 only done once, and is cached when the symbol table for a file is read in.
4853 This results in a small increase in memory usage for C programs, a moderate
4854 increase in memory usage for C++ programs, and a fantastic speedup in
4857 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4858 from the specifications in the Annotated Reference Manual, which AT&T's
4859 compiler does not actually implement.
4861 * G++ multiple inheritance compiler problem
4863 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4864 inheritance lattices was reworked to properly discover ambiguities. We
4865 recently found an example which causes this new algorithm to fail in a
4866 very subtle way, producing bad debug information for those classes.
4867 The file 'gcc.patch' (in this directory) can be applied to gcc to
4868 circumvent the problem. A future GCC release will contain a complete
4871 The previous G++ debug info problem (mentioned below for the gdb-4.7
4872 release) is fixed in gcc version 2.3.2.
4874 * Improved configure script
4876 The `configure' script will now attempt to guess your system type if
4877 you don't supply a host system type. The old scheme of supplying a
4878 host system triplet is preferable over using this. All the magic is
4879 done in the new `config.guess' script. Examine it for details.
4881 We have also brought our configure script much more in line with the FSF's
4882 version. It now supports the --with-xxx options. In particular,
4883 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4884 The resulting GDB will not be able to read arbitrary object file formats --
4885 only the format ``expected'' to be used on the configured target system.
4886 We hope to make this the default in a future release.
4888 * Documentation improvements
4890 There's new internal documentation on how to modify GDB, and how to
4891 produce clean changes to the code. We implore people to read it
4892 before submitting changes.
4894 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4895 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4896 `info' files are also provided. To build `info' files from scratch,
4897 you will need the latest `makeinfo' release, which will be available in
4898 a future texinfo-X.Y release.
4900 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4901 We're not sure exactly which versions have this problem, but it has
4902 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4903 or better. If that isn't possible, there is a patch in
4904 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4905 around this problem.
4909 GDB now supports array constants that can be used in expressions typed in by
4910 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4911 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4914 The new directory `gdb/sparclite' contains a program that demonstrates
4915 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4917 * New native hosts supported
4919 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4920 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4922 * New targets supported
4924 AMD 29k family via UDI a29k-amd-udi or udi29k
4926 * New file formats supported
4928 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4929 HPUX core files, and SCO 3.2v2 core files.
4933 Attaching to processes now works again; thanks for the many bug reports.
4935 We have also stomped on a bunch of core dumps caused by
4936 printf_filtered("%s") problems.
4938 We eliminated a copyright problem on the rpc and ptrace header files
4939 for VxWorks, which was discovered at the last minute during the 4.7
4940 release. You should now be able to build a VxWorks GDB.
4942 You can now interrupt gdb while an attached process is running. This
4943 will cause the attached process to stop, and give control back to GDB.
4945 We fixed problems caused by using too many file descriptors
4946 for reading symbols from object files and libraries. This was
4947 especially a problem for programs that used many (~100) shared
4950 The `step' command now only enters a subroutine if there is line number
4951 information for the subroutine. Otherwise it acts like the `next'
4952 command. Previously, `step' would enter subroutines if there was
4953 any debugging information about the routine. This avoids problems
4954 when using `cc -g1' on MIPS machines.
4956 * Internal improvements
4958 GDB's internal interfaces have been improved to make it easier to support
4959 debugging of multiple languages in the future.
4961 GDB now uses a common structure for symbol information internally.
4962 Minimal symbols (derived from linkage symbols in object files), partial
4963 symbols (from a quick scan of debug information), and full symbols
4964 contain a common subset of information, making it easier to write
4965 shared code that handles any of them.
4967 * New command line options
4969 We now accept --silent as an alias for --quiet.
4973 The memory-mapped-malloc library is now licensed under the GNU Library
4974 General Public License.
4976 *** Changes in GDB-4.7:
4978 * Host/native/target split
4980 GDB has had some major internal surgery to untangle the support for
4981 hosts and remote targets. Now, when you configure GDB for a remote
4982 target, it will no longer load in all of the support for debugging
4983 local programs on the host. When fully completed and tested, this will
4984 ensure that arbitrary host/target combinations are possible.
4986 The primary conceptual shift is to separate the non-portable code in
4987 GDB into three categories. Host specific code is required any time GDB
4988 is compiled on that host, regardless of the target. Target specific
4989 code relates to the peculiarities of the target, but can be compiled on
4990 any host. Native specific code is everything else: it can only be
4991 built when the host and target are the same system. Child process
4992 handling and core file support are two common `native' examples.
4994 GDB's use of /proc for controlling Unix child processes is now cleaner.
4995 It has been split out into a single module under the `target_ops' vector,
4996 plus two native-dependent functions for each system that uses /proc.
4998 * New hosts supported
5000 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5001 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5002 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5004 * New targets supported
5006 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5007 68030 and CPU32 m68030-*-*, m68332-*-*
5009 * New native hosts supported
5011 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5012 (386bsd is not well tested yet)
5013 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5015 * New file formats supported
5017 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5018 supports reading of `a.out.adobe' object files, which are an a.out
5019 format extended with minimal information about multiple sections.
5023 `show copying' is the same as the old `info copying'.
5024 `show warranty' is the same as `info warrantee'.
5025 These were renamed for consistency. The old commands continue to work.
5027 `info handle' is a new alias for `info signals'.
5029 You can now define pre-command hooks, which attach arbitrary command
5030 scripts to any command. The commands in the hook will be executed
5031 prior to the user's command. You can also create a hook which will be
5032 executed whenever the program stops. See gdb.texinfo.
5036 We now deal with Cfront style name mangling, and can even extract type
5037 info from mangled symbols. GDB can automatically figure out which
5038 symbol mangling style your C++ compiler uses.
5040 Calling of methods and virtual functions has been improved as well.
5044 The crash that occured when debugging Sun Ansi-C compiled binaries is
5045 fixed. This was due to mishandling of the extra N_SO stabs output
5048 We also finally got Ultrix 4.2 running in house, and fixed core file
5049 support, with help from a dozen people on the net.
5051 John M. Farrell discovered that the reason that single-stepping was so
5052 slow on all of the Mips based platforms (primarily SGI and DEC) was
5053 that we were trying to demangle and lookup a symbol used for internal
5054 purposes on every instruction that was being stepped through. Changing
5055 the name of that symbol so that it couldn't be mistaken for a C++
5056 mangled symbol sped things up a great deal.
5058 Rich Pixley sped up symbol lookups in general by getting much smarter
5059 about when C++ symbol mangling is necessary. This should make symbol
5060 completion (TAB on the command line) much faster. It's not as fast as
5061 we'd like, but it's significantly faster than gdb-4.6.
5065 A new user controllable variable 'call_scratch_address' can
5066 specify the location of a scratch area to be used when GDB
5067 calls a function in the target. This is necessary because the
5068 usual method of putting the scratch area on the stack does not work
5069 in systems that have separate instruction and data spaces.
5071 We integrated changes to support the 29k UDI (Universal Debugger
5072 Interface), but discovered at the last minute that we didn't have all
5073 of the appropriate copyright paperwork. We are working with AMD to
5074 resolve this, and hope to have it available soon.
5078 We have sped up the remote serial line protocol, especially for targets
5079 with lots of registers. It now supports a new `expedited status' ('T')
5080 message which can be used in place of the existing 'S' status message.
5081 This allows the remote stub to send only the registers that GDB
5082 needs to make a quick decision about single-stepping or conditional
5083 breakpoints, eliminating the need to fetch the entire register set for
5084 each instruction being stepped through.
5086 The GDB remote serial protocol now implements a write-through cache for
5087 registers, only re-reading the registers if the target has run.
5089 There is also a new remote serial stub for SPARC processors. You can
5090 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5091 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5092 processor with a serial port.
5096 Configure.in files have become much easier to read and modify. A new
5097 `table driven' format makes it more obvious what configurations are
5098 supported, and what files each one uses.
5102 There is a new opcodes library which will eventually contain all of the
5103 disassembly routines and opcode tables. At present, it only contains
5104 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5105 disassembler (binutils/objdump) to share these routines.
5107 The libiberty library is now copylefted under the GNU Library General
5108 Public License. This allows more liberal use, and was done so libg++
5109 can use it. This makes no difference to GDB, since the Library License
5110 grants all the rights from the General Public License.
5114 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5115 reference to the stabs symbol info used by the debugger. It is (as far
5116 as we know) the only published document on this fascinating topic. We
5117 encourage you to read it, compare it to the stabs information on your
5118 system, and send improvements on the document in general (to
5119 bug-gdb@prep.ai.mit.edu).
5121 And, of course, many bugs have been fixed.
5124 *** Changes in GDB-4.6:
5126 * Better support for C++ function names
5128 GDB now accepts as input the "demangled form" of C++ overloaded function
5129 names and member function names, and can do command completion on such names
5130 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5131 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5132 Make use of command completion, it is your friend.
5134 GDB also now accepts a variety of C++ mangled symbol formats. They are
5135 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5136 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5137 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5138 for the list of formats.
5140 * G++ symbol mangling problem
5142 Recent versions of gcc have a bug in how they emit debugging information for
5143 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5144 directory) can be applied to gcc to fix the problem. Alternatively, if you
5145 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5146 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5147 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5150 * New 'maintenance' command
5152 All of the commands related to hacking GDB internals have been moved out of
5153 the main command set, and now live behind the 'maintenance' command. This
5154 can also be abbreviated as 'mt'. The following changes were made:
5156 dump-me -> maintenance dump-me
5157 info all-breakpoints -> maintenance info breakpoints
5158 printmsyms -> maintenance print msyms
5159 printobjfiles -> maintenance print objfiles
5160 printpsyms -> maintenance print psymbols
5161 printsyms -> maintenance print symbols
5163 The following commands are new:
5165 maintenance demangle Call internal GDB demangler routine to
5166 demangle a C++ link name and prints the result.
5167 maintenance print type Print a type chain for a given symbol
5169 * Change to .gdbinit file processing
5171 We now read the $HOME/.gdbinit file before processing the argv arguments
5172 (e.g. reading symbol files or core files). This allows global parameters to
5173 be set, which will apply during the symbol reading. The ./.gdbinit is still
5174 read after argv processing.
5176 * New hosts supported
5178 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5180 GNU/Linux support i386-unknown-linux or linux
5182 We are also including code to support the HP/PA running BSD and HPUX. This
5183 is almost guaranteed not to work, as we didn't have time to test or build it
5184 for this release. We are including it so that the more adventurous (or
5185 masochistic) of you can play with it. We also had major problems with the
5186 fact that the compiler that we got from HP doesn't support the -g option.
5189 * New targets supported
5191 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5193 * More smarts about finding #include files
5195 GDB now remembers the compilation directory for all include files, and for
5196 all files from which C is generated (like yacc and lex sources). This
5197 greatly improves GDB's ability to find yacc/lex sources, and include files,
5198 especially if you are debugging your program from a directory different from
5199 the one that contains your sources.
5201 We also fixed a bug which caused difficulty with listing and setting
5202 breakpoints in include files which contain C code. (In the past, you had to
5203 try twice in order to list an include file that you hadn't looked at before.)
5205 * Interesting infernals change
5207 GDB now deals with arbitrary numbers of sections, where the symbols for each
5208 section must be relocated relative to that section's landing place in the
5209 target's address space. This work was needed to support ELF with embedded
5210 stabs used by Solaris-2.0.
5212 * Bug fixes (of course!)
5214 There have been loads of fixes for the following things:
5215 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5216 i960, stabs, DOS(GO32), procfs, etc...
5218 See the ChangeLog for details.
5220 *** Changes in GDB-4.5:
5222 * New machines supported (host and target)
5224 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5226 SGI Irix-4.x mips-sgi-irix4 or iris4
5228 * New malloc package
5230 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5231 Mmalloc is capable of handling mutiple heaps of memory. It is also
5232 capable of saving a heap to a file, and then mapping it back in later.
5233 This can be used to greatly speedup the startup of GDB by using a
5234 pre-parsed symbol table which lives in a mmalloc managed heap. For
5235 more details, please read mmalloc/mmalloc.texi.
5239 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5240 'help info proc' for details.
5242 * MIPS ecoff symbol table format
5244 The code that reads MIPS symbol table format is now supported on all hosts.
5245 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5248 * File name changes for MS-DOS
5250 Many files in the config directories have been renamed to make it easier to
5251 support GDB on MS-DOSe systems (which have very restrictive file name
5252 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5253 environment) is close to working but has some remaining problems. Note
5254 that debugging of DOS programs is not supported, due to limitations
5255 in the ``operating system'', but it can be used to host cross-debugging.
5257 * Cross byte order fixes
5259 Many fixes have been made to support cross debugging of Sparc and MIPS
5260 targets from hosts whose byte order differs.
5262 * New -mapped and -readnow options
5264 If memory-mapped files are available on your system through the 'mmap'
5265 system call, you can use the -mapped option on the `file' or
5266 `symbol-file' commands to cause GDB to write the symbols from your
5267 program into a reusable file. If the program you are debugging is
5268 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5269 Future GDB debugging sessions will notice the presence of this file,
5270 and will quickly map in symbol information from it, rather than reading
5271 the symbol table from the executable program. Using the '-mapped'
5272 option in a GDB `file' or `symbol-file' command has the same effect as
5273 starting GDB with the '-mapped' command-line option.
5275 You can cause GDB to read the entire symbol table immediately by using
5276 the '-readnow' option with any of the commands that load symbol table
5277 information (or on the GDB command line). This makes the command
5278 slower, but makes future operations faster.
5280 The -mapped and -readnow options are typically combined in order to
5281 build a `fred.syms' file that contains complete symbol information.
5282 A simple GDB invocation to do nothing but build a `.syms' file for future
5285 gdb -batch -nx -mapped -readnow programname
5287 The `.syms' file is specific to the host machine on which GDB is run.
5288 It holds an exact image of GDB's internal symbol table. It cannot be
5289 shared across multiple host platforms.
5291 * longjmp() handling
5293 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5294 siglongjmp() without losing control. This feature has not yet been ported to
5295 all systems. It currently works on many 386 platforms, all MIPS-based
5296 platforms (SGI, DECstation, etc), and Sun3/4.
5300 Preliminary work has been put in to support the new Solaris OS from Sun. At
5301 this time, it can control and debug processes, but it is not capable of
5306 As always, many many bug fixes. The major areas were with g++, and mipsread.
5307 People using the MIPS-based platforms should experience fewer mysterious
5308 crashes and trashed symbol tables.
5310 *** Changes in GDB-4.4:
5312 * New machines supported (host and target)
5314 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5316 BSD Reno on Vax vax-dec-bsd
5317 Ultrix on Vax vax-dec-ultrix
5319 * New machines supported (target)
5321 AMD 29000 embedded, using EBMON a29k-none-none
5325 GDB continues to improve its handling of C++. `References' work better.
5326 The demangler has also been improved, and now deals with symbols mangled as
5327 per the Annotated C++ Reference Guide.
5329 GDB also now handles `stabs' symbol information embedded in MIPS
5330 `ecoff' symbol tables. Since the ecoff format was not easily
5331 extensible to handle new languages such as C++, this appeared to be a
5332 good way to put C++ debugging info into MIPS binaries. This option
5333 will be supported in the GNU C compiler, version 2, when it is
5336 * New features for SVR4
5338 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5339 shared libraries. Debugging dynamically linked programs should present
5340 only minor differences from debugging statically linked programs.
5342 The `info proc' command will print out information about any process
5343 on an SVR4 system (including the one you are debugging). At the moment,
5344 it prints the address mappings of the process.
5346 If you bring up GDB on another SVR4 system, please send mail to
5347 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5349 * Better dynamic linking support in SunOS
5351 Reading symbols from shared libraries which contain debugging symbols
5352 now works properly. However, there remain issues such as automatic
5353 skipping of `transfer vector' code during function calls, which
5354 make it harder to debug code in a shared library, than to debug the
5355 same code linked statically.
5359 GDB is now using the latest `getopt' routines from the FSF. This
5360 version accepts the -- prefix for options with long names. GDB will
5361 continue to accept the old forms (-option and +option) as well.
5362 Various single letter abbreviations for options have been explicity
5363 added to the option table so that they won't get overshadowed in the
5364 future by other options that begin with the same letter.
5368 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5369 Many assorted bugs have been handled. Many more remain to be handled.
5370 See the various ChangeLog files (primarily in gdb and bfd) for details.
5373 *** Changes in GDB-4.3:
5375 * New machines supported (host and target)
5377 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5378 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5379 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5381 * Almost SCO Unix support
5383 We had hoped to support:
5384 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5385 (except for core file support), but we discovered very late in the release
5386 that it has problems with process groups that render gdb unusable. Sorry
5387 about that. I encourage people to fix it and post the fixes.
5389 * Preliminary ELF and DWARF support
5391 GDB can read ELF object files on System V Release 4, and can handle
5392 debugging records for C, in DWARF format, in ELF files. This support
5393 is preliminary. If you bring up GDB on another SVR4 system, please
5394 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5399 GDB now uses the latest `readline' library. One user-visible change
5400 is that two tabs will list possible command completions, which previously
5401 required typing M-? (meta-question mark, or ESC ?).
5405 The `stepi' bug that many of you noticed has been squashed.
5406 Many bugs in C++ have been handled. Many more remain to be handled.
5407 See the various ChangeLog files (primarily in gdb and bfd) for details.
5409 * State of the MIPS world (in case you wondered):
5411 GDB can understand the symbol tables emitted by the compilers
5412 supplied by most vendors of MIPS-based machines, including DEC. These
5413 symbol tables are in a format that essentially nobody else uses.
5415 Some versions of gcc come with an assembler post-processor called
5416 mips-tfile. This program is required if you want to do source-level
5417 debugging of gcc-compiled programs. I believe FSF does not ship
5418 mips-tfile with gcc version 1, but it will eventually come with gcc
5421 Debugging of g++ output remains a problem. g++ version 1.xx does not
5422 really support it at all. (If you're lucky, you should be able to get
5423 line numbers and stack traces to work, but no parameters or local
5424 variables.) With some work it should be possible to improve the
5427 When gcc version 2 is released, you will have somewhat better luck.
5428 However, even then you will get confusing results for inheritance and
5431 We will eventually provide full debugging of g++ output on
5432 DECstations. This will probably involve some kind of stabs-in-ecoff
5433 encapulation, but the details have not been worked out yet.
5436 *** Changes in GDB-4.2:
5438 * Improved configuration
5440 Only one copy of `configure' exists now, and it is not self-modifying.
5441 Porting BFD is simpler.
5445 The `step' and `next' commands now only stop at the first instruction
5446 of a source line. This prevents the multiple stops that used to occur
5447 in switch statements, for-loops, etc. `Step' continues to stop if a
5448 function that has debugging information is called within the line.
5452 Lots of small bugs fixed. More remain.
5454 * New host supported (not target)
5456 Intel 386 PC clone running Mach i386-none-mach
5459 *** Changes in GDB-4.1:
5461 * Multiple source language support
5463 GDB now has internal scaffolding to handle several source languages.
5464 It determines the type of each source file from its filename extension,
5465 and will switch expression parsing and number formatting to match the
5466 language of the function in the currently selected stack frame.
5467 You can also specifically set the language to be used, with
5468 `set language c' or `set language modula-2'.
5472 GDB now has preliminary support for the GNU Modula-2 compiler,
5473 currently under development at the State University of New York at
5474 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5475 continue through the fall of 1991 and into 1992.
5477 Other Modula-2 compilers are currently not supported, and attempting to
5478 debug programs compiled with them will likely result in an error as the
5479 symbol table is read. Feel free to work on it, though!
5481 There are hooks in GDB for strict type checking and range checking,
5482 in the `Modula-2 philosophy', but they do not currently work.
5486 GDB can now write to executable and core files (e.g. patch
5487 a variable's value). You must turn this switch on, specify
5488 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5489 by assigning a new value to a variable. Modifications take
5492 * Automatic SunOS shared library reading
5494 When you run your program, GDB automatically determines where its
5495 shared libraries (if any) have been loaded, and reads their symbols.
5496 The `share' command is no longer needed. This also works when
5497 examining core files.
5501 You can specify the number of lines that the `list' command shows.
5504 * New machines supported (host and target)
5506 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5507 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5508 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5510 * New hosts supported (not targets)
5512 IBM RT/PC: romp-ibm-aix or rtpc
5514 * New targets supported (not hosts)
5516 AMD 29000 embedded with COFF a29k-none-coff
5517 AMD 29000 embedded with a.out a29k-none-aout
5518 Ultracomputer remote kernel debug a29k-nyu-kern
5520 * New remote interfaces
5526 *** Changes in GDB-4.0:
5530 Wide output is wrapped at good places to make the output more readable.
5532 Gdb now supports cross-debugging from a host machine of one type to a
5533 target machine of another type. Communication with the target system
5534 is over serial lines. The ``target'' command handles connecting to the
5535 remote system; the ``load'' command will download a program into the
5536 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5537 also supports debugging of realtime processes running under VxWorks,
5538 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5539 stub on the target system.
5541 New CPUs supported include the AMD 29000 and Intel 960.
5543 GDB now reads object files and symbol tables via a ``binary file''
5544 library, which allows a single copy of GDB to debug programs of multiple
5545 object file types such as a.out and coff.
5547 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5548 refcard.dvi and refcard.ps are available to format it).
5551 * Control-Variable user interface simplified
5553 All variables that control the operation of the debugger can be set
5554 by the ``set'' command, and displayed by the ``show'' command.
5556 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5557 ``Show prompt'' produces the response:
5558 Gdb's prompt is new-gdb=>.
5560 What follows are the NEW set commands. The command ``help set'' will
5561 print a complete list of old and new set commands. ``help set FOO''
5562 will give a longer description of the variable FOO. ``show'' will show
5563 all of the variable descriptions and their current settings.
5565 confirm on/off: Enables warning questions for operations that are
5566 hard to recover from, e.g. rerunning the program while
5567 it is already running. Default is ON.
5569 editing on/off: Enables EMACS style command line editing
5570 of input. Previous lines can be recalled with
5571 control-P, the current line can be edited with control-B,
5572 you can search for commands with control-R, etc.
5575 history filename NAME: NAME is where the gdb command history
5576 will be stored. The default is .gdb_history,
5577 or the value of the environment variable
5580 history size N: The size, in commands, of the command history. The
5581 default is 256, or the value of the environment variable
5584 history save on/off: If this value is set to ON, the history file will
5585 be saved after exiting gdb. If set to OFF, the
5586 file will not be saved. The default is OFF.
5588 history expansion on/off: If this value is set to ON, then csh-like
5589 history expansion will be performed on
5590 command line input. The default is OFF.
5592 radix N: Sets the default radix for input and output. It can be set
5593 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5594 in the current radix, so "set radix 10" is always a no-op.
5596 height N: This integer value is the number of lines on a page. Default
5597 is 24, the current `stty rows'' setting, or the ``li#''
5598 setting from the termcap entry matching the environment
5601 width N: This integer value is the number of characters on a line.
5602 Default is 80, the current `stty cols'' setting, or the ``co#''
5603 setting from the termcap entry matching the environment
5606 Note: ``set screensize'' is obsolete. Use ``set height'' and
5607 ``set width'' instead.
5609 print address on/off: Print memory addresses in various command displays,
5610 such as stack traces and structure values. Gdb looks
5611 more ``symbolic'' if you turn this off; it looks more
5612 ``machine level'' with it on. Default is ON.
5614 print array on/off: Prettyprint arrays. New convenient format! Default
5617 print demangle on/off: Print C++ symbols in "source" form if on,
5620 print asm-demangle on/off: Same, for assembler level printouts
5623 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5626 * Support for Epoch Environment.
5628 The epoch environment is a version of Emacs v18 with windowing. One
5629 new command, ``inspect'', is identical to ``print'', except that if you
5630 are running in the epoch environment, the value is printed in its own
5634 * Support for Shared Libraries
5636 GDB can now debug programs and core files that use SunOS shared libraries.
5637 Symbols from a shared library cannot be referenced
5638 before the shared library has been linked with the program (this
5639 happens after you type ``run'' and before the function main() is entered).
5640 At any time after this linking (including when examining core files
5641 from dynamically linked programs), gdb reads the symbols from each
5642 shared library when you type the ``sharedlibrary'' command.
5643 It can be abbreviated ``share''.
5645 sharedlibrary REGEXP: Load shared object library symbols for files
5646 matching a unix regular expression. No argument
5647 indicates to load symbols for all shared libraries.
5649 info sharedlibrary: Status of loaded shared libraries.
5654 A watchpoint stops execution of a program whenever the value of an
5655 expression changes. Checking for this slows down execution
5656 tremendously whenever you are in the scope of the expression, but is
5657 quite useful for catching tough ``bit-spreader'' or pointer misuse
5658 problems. Some machines such as the 386 have hardware for doing this
5659 more quickly, and future versions of gdb will use this hardware.
5661 watch EXP: Set a watchpoint (breakpoint) for an expression.
5663 info watchpoints: Information about your watchpoints.
5665 delete N: Deletes watchpoint number N (same as breakpoints).
5666 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5667 enable N: Re-enables watchpoint number N (same as breakpoints).
5670 * C++ multiple inheritance
5672 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5675 * C++ exception handling
5677 Gdb now supports limited C++ exception handling. Besides the existing
5678 ability to breakpoint on an exception handler, gdb can breakpoint on
5679 the raising of an exception (before the stack is peeled back to the
5682 catch FOO: If there is a FOO exception handler in the dynamic scope,
5683 set a breakpoint to catch exceptions which may be raised there.
5684 Multiple exceptions (``catch foo bar baz'') may be caught.
5686 info catch: Lists all exceptions which may be caught in the
5687 current stack frame.
5690 * Minor command changes
5692 The command ``call func (arg, arg, ...)'' now acts like the print
5693 command, except it does not print or save a value if the function's result
5694 is void. This is similar to dbx usage.
5696 The ``up'' and ``down'' commands now always print the frame they end up
5697 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5698 frames without printing.
5700 * New directory command
5702 'dir' now adds directories to the FRONT of the source search path.
5703 The path starts off empty. Source files that contain debug information
5704 about the directory in which they were compiled can be found even
5705 with an empty path; Sun CC and GCC include this information. If GDB can't
5706 find your source file in the current directory, type "dir .".
5708 * Configuring GDB for compilation
5710 For normal use, type ``./configure host''. See README or gdb.texinfo
5713 GDB now handles cross debugging. If you are remotely debugging between
5714 two different machines, type ``./configure host -target=targ''.
5715 Host is the machine where GDB will run; targ is the machine
5716 where the program that you are debugging will run.
5718 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5720 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5722 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5723 $k0 - $k7 on GNU/Linux.