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 set auto-connect-native-target
66 Control whether GDB is allowed to automatically connect to the
67 native target for the run, attach, etc. commands when not connected
68 to any target yet. See also "target native" below.
70 set record btrace replay-memory-access (read-only|read-write)
71 show record btrace replay-memory-access
72 Control what memory accesses are allowed during replay.
74 maint set target-async (on|off)
75 maint show target-async
76 This controls whether GDB targets operate in syncronous or
77 asyncronous mode. Normally the default is asyncronous, if it is
78 available; but this can be changed to more easily debug problems
79 occurring only in syncronous mode.
83 Control whether MI asynchronous mode is preferred. This supersedes
84 "set target-async" of previous GDB versions.
86 * "set target-async" is deprecated as a CLI option and is now an alias
87 for "set mi-async" (only puts MI into async mode).
89 * Background execution commands (e.g., "c&", "s&", etc.) are now
90 possible ``out of the box'' if the target supports them. Previously
91 the user would need to explicitly enable the possibility with the
92 "set target-async on" command.
94 * New features in the GDB remote stub, GDBserver
96 ** New option --debug-format=option1[,option2,...] allows one to add
97 additional text to each output. At present only timestamps
98 are supported: --debug-format=timestamps.
99 Timestamps can also be turned on with the
100 "monitor set debug-format timestamps" command from GDB.
102 * The 'record instruction-history' command now starts counting instructions
103 at one. This also affects the instruction ranges reported by the
104 'record function-call-history' command when given the /i modifier.
106 * The command 'record function-call-history' supports a new modifier '/c' to
107 indent the function names based on their call stack depth.
108 The fields for the '/i' and '/l' modifier have been reordered.
109 The source line range is now prefixed with 'at'.
110 The instruction range is now prefixed with 'inst'.
111 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
112 "record instruction-history" and "list" commands.
114 * The ranges given as arguments to the 'record function-call-history' and
115 'record instruction-history' commands are now inclusive.
117 * The btrace record target now supports the 'record goto' command.
118 For locations inside the execution trace, the back trace is computed
119 based on the information stored in the execution trace.
121 * The btrace record target supports limited reverse execution and replay.
122 The target does not record data and therefore does not allow reading
125 * The "catch syscall" command now works on s390*-linux* targets.
127 * The "compare-sections" command is no longer specific to target
128 remote. It now works with all targets.
130 * All native targets are now consistently called "native".
131 Consequently, the "target child", "target GNU", "target djgpp",
132 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
133 commands have been replaced with "target native". The QNX/NTO port
134 leaves the "procfs" target in place and adds a "native" target for
135 consistency with other ports. The impact on users should be minimal
136 as these commands previously either throwed an error, or were
137 no-ops. The target's name is visible in the output of the following
138 commands: "help target", "info target", "info files", "maint print
141 * The "target native" command now connects to the native target. This
142 can be used to launch native programs even when "set
143 auto-connect-native-target" is set to off.
147 qXfer:btrace:read's annex
148 The qXfer:btrace:read packet supports a new annex 'delta' to read
149 branch trace incrementally.
153 ** Valid Python operations on gdb.Value objects representing
154 structs/classes invoke the corresponding overloaded operators if
158 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
160 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
161 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
162 its alias "share", instead.
164 * The commands "set remotebaud" and "show remotebaud" are no longer
165 supported. Use "set serial baud" and "show serial baud" (respectively)
170 ** A new option "-gdb-set mi-async" replaces "-gdb-set
171 target-async". The latter is left as a deprecated alias of the
172 former for backward compatibility. If the target supports it,
173 CLI background execution commands are now always possible by
174 default, independently of whether the frontend stated a
175 preference for asynchronous execution with "-gdb-set mi-async".
176 Previously "-gdb-set target-async off" affected both MI execution
177 commands and CLI execution commands.
179 *** Changes in GDB 7.7
181 * Improved support for process record-replay and reverse debugging on
182 arm*-linux* targets. Support for thumb32 and syscall instruction
183 recording has been added.
185 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
187 * GDB now supports Fission DWP file format version 2.
188 http://gcc.gnu.org/wiki/DebugFission
190 * New convenience function "$_isvoid", to check whether an expression
191 is void. A void expression is an expression where the type of the
192 result is "void". For example, some convenience variables may be
193 "void" when evaluated (e.g., "$_exitcode" before the execution of
194 the program being debugged; or an undefined convenience variable).
195 Another example, when calling a function whose return type is
198 * The "maintenance print objfiles" command now takes an optional regexp.
200 * The "catch syscall" command now works on arm*-linux* targets.
202 * GDB now consistently shows "<not saved>" when printing values of
203 registers the debug info indicates have not been saved in the frame
204 and there's nowhere to retrieve them from
205 (callee-saved/call-clobbered registers):
210 (gdb) info registers rax
213 Before, the former would print "<optimized out>", and the latter
214 "*value not available*".
216 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
221 ** Frame filters and frame decorators have been added.
222 ** Temporary breakpoints are now supported.
223 ** Line tables representation has been added.
224 ** New attribute 'parent_type' for gdb.Field objects.
225 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
226 ** New attribute 'name' for gdb.Type objects.
230 Nios II ELF nios2*-*-elf
231 Nios II GNU/Linux nios2*-*-linux
232 Texas Instruments MSP430 msp430*-*-elf
234 * Removed native configurations
236 Support for these a.out NetBSD and OpenBSD obsolete configurations has
237 been removed. ELF variants of these configurations are kept supported.
239 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
240 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
241 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
242 i[34567]86-*-openbsd3.[0-3]
243 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
244 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
245 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
249 Like "catch throw", but catches a re-thrown exception.
251 Renamed from old "maint check-symtabs".
253 Perform consistency checks on symtabs.
255 Expand symtabs matching an optional regexp.
258 Display the details of GDB configure-time options.
260 maint set|show per-command
261 maint set|show per-command space
262 maint set|show per-command time
263 maint set|show per-command symtab
264 Enable display of per-command gdb resource usage.
266 remove-symbol-file FILENAME
267 remove-symbol-file -a ADDRESS
268 Remove a symbol file added via add-symbol-file. The file to remove
269 can be identified by its filename or by an address that lies within
270 the boundaries of this symbol file in memory.
273 info exceptions REGEXP
274 Display the list of Ada exceptions defined in the program being
275 debugged. If provided, only the exceptions whose names match REGEXP
280 set debug symfile off|on
282 Control display of debugging info regarding reading symbol files and
283 symbol tables within those files
285 set print raw frame-arguments
286 show print raw frame-arguments
287 Set/show whether to print frame arguments in raw mode,
288 disregarding any defined pretty-printers.
290 set remote trace-status-packet
291 show remote trace-status-packet
292 Set/show the use of remote protocol qTStatus packet.
296 Control display of debugging messages related to Nios II targets.
300 Control whether target-assisted range stepping is enabled.
302 set startup-with-shell
303 show startup-with-shell
304 Specifies whether Unix child processes are started via a shell or
309 Use the target memory cache for accesses to the code segment. This
310 improves performance of remote debugging (particularly disassembly).
312 * You can now use a literal value 'unlimited' for options that
313 interpret 0 or -1 as meaning "unlimited". E.g., "set
314 trace-buffer-size unlimited" is now an alias for "set
315 trace-buffer-size -1" and "set height unlimited" is now an alias for
318 * The "set debug symtab-create" debugging option of GDB has been changed to
319 accept a verbosity level. 0 means "off", 1 provides basic debugging
320 output, and values of 2 or greater provides more verbose output.
322 * New command-line options
324 Display the details of GDB configure-time options.
326 * The command 'tsave' can now support new option '-ctf' to save trace
327 buffer in Common Trace Format.
329 * Newly installed $prefix/bin/gcore acts as a shell interface for the
332 * GDB now implements the the C++ 'typeid' operator.
334 * The new convenience variable $_exception holds the exception being
335 thrown or caught at an exception-related catchpoint.
337 * The exception-related catchpoints, like "catch throw", now accept a
338 regular expression which can be used to filter exceptions by type.
340 * The new convenience variable $_exitsignal is automatically set to
341 the terminating signal number when the program being debugged dies
342 due to an uncaught signal.
346 ** All MI commands now accept an optional "--language" option.
347 Support for this feature can be verified by using the "-list-features"
348 command, which should contain "language-option".
350 ** The new command -info-gdb-mi-command allows the user to determine
351 whether a GDB/MI command is supported or not.
353 ** The "^error" result record returned when trying to execute an undefined
354 GDB/MI command now provides a variable named "code" whose content is the
355 "undefined-command" error code. Support for this feature can be verified
356 by using the "-list-features" command, which should contain
357 "undefined-command-error-code".
359 ** The -trace-save MI command can optionally save trace buffer in Common
362 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
364 ** The command -data-list-register-values now accepts an optional
365 "--skip-unavailable" option. When used, only the available registers
368 ** The new command -trace-frame-collected dumps collected variables,
369 computed expressions, tvars, memory and registers in a traceframe.
371 ** The commands -stack-list-locals, -stack-list-arguments and
372 -stack-list-variables now accept an option "--skip-unavailable".
373 When used, only the available locals or arguments are displayed.
375 ** The -exec-run command now accepts an optional "--start" option.
376 When used, the command follows the same semantics as the "start"
377 command, stopping the program's execution at the start of its
378 main subprogram. Support for this feature can be verified using
379 the "-list-features" command, which should contain
380 "exec-run-start-option".
382 ** The new commands -catch-assert and -catch-exceptions insert
383 catchpoints stopping the program when Ada exceptions are raised.
385 ** The new command -info-ada-exceptions provides the equivalent of
386 the new "info exceptions" command.
388 * New system-wide configuration scripts
389 A GDB installation now provides scripts suitable for use as system-wide
390 configuration scripts for the following systems:
394 * GDB now supports target-assigned range stepping with remote targets.
395 This improves the performance of stepping source lines by reducing
396 the number of control packets from/to GDB. See "New remote packets"
399 * GDB now understands the element 'tvar' in the XML traceframe info.
400 It has the id of the collected trace state variables.
402 * On S/390 targets that provide the transactional-execution feature,
403 the program interruption transaction diagnostic block (TDB) is now
404 represented as a number of additional "registers" in GDB.
410 The vCont packet supports a new 'r' action, that tells the remote
411 stub to step through an address range itself, without GDB
412 involvemement at each single-step.
414 qXfer:libraries-svr4:read's annex
415 The previously unused annex of the qXfer:libraries-svr4:read packet
416 is now used to support passing an argument list. The remote stub
417 reports support for this argument list to GDB's qSupported query.
418 The defined arguments are "start" and "prev", used to reduce work
419 necessary for library list updating, resulting in significant
422 * New features in the GDB remote stub, GDBserver
424 ** GDBserver now supports target-assisted range stepping. Currently
425 enabled on x86/x86_64 GNU/Linux targets.
427 ** GDBserver now adds element 'tvar' in the XML in the reply to
428 'qXfer:traceframe-info:read'. It has the id of the collected
429 trace state variables.
431 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
434 * New 'z' formatter for printing and examining memory, this displays the
435 value as hexadecimal zero padded on the left to the size of the type.
437 * GDB can now use Windows x64 unwinding data.
439 * The "set remotebaud" command has been replaced by "set serial baud".
440 Similarly, "show remotebaud" has been replaced by "show serial baud".
441 The "set remotebaud" and "show remotebaud" commands are still available
442 to provide backward compatibility with older versions of GDB.
444 *** Changes in GDB 7.6
446 * Target record has been renamed to record-full.
447 Record/replay is now enabled with the "record full" command.
448 This also affects settings that are associated with full record/replay
449 that have been moved from "set/show record" to "set/show record full":
451 set|show record full insn-number-max
452 set|show record full stop-at-limit
453 set|show record full memory-query
455 * A new record target "record-btrace" has been added. The new target
456 uses hardware support to record the control-flow of a process. It
457 does not support replaying the execution, but it implements the
458 below new commands for investigating the recorded execution log.
459 This new recording method can be enabled using:
463 The "record-btrace" target is only available on Intel Atom processors
464 and requires a Linux kernel 2.6.32 or later.
466 * Two new commands have been added for record/replay to give information
467 about the recorded execution without having to replay the execution.
468 The commands are only supported by "record btrace".
470 record instruction-history prints the execution history at
471 instruction granularity
473 record function-call-history prints the execution history at
476 * New native configurations
478 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
479 FreeBSD/powerpc powerpc*-*-freebsd
480 x86_64/Cygwin x86_64-*-cygwin*
481 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
485 ARM AArch64 aarch64*-*-elf
486 ARM AArch64 GNU/Linux aarch64*-*-linux
487 Lynx 178 PowerPC powerpc-*-lynx*178
488 x86_64/Cygwin x86_64-*-cygwin*
489 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
491 * If the configured location of system.gdbinit file (as given by the
492 --with-system-gdbinit option at configure time) is in the
493 data-directory (as specified by --with-gdb-datadir at configure
494 time) or in one of its subdirectories, then GDB will look for the
495 system-wide init file in the directory specified by the
496 --data-directory command-line option.
498 * New command line options:
500 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
501 other initialization files, unlike -nx which disables all of them.
503 * Removed command line options
505 -epoch This was used by the gdb mode in Epoch, an ancient fork of
508 * The 'ptype' and 'whatis' commands now accept an argument to control
511 * 'info proc' now works on some core files.
515 ** Vectors can be created with gdb.Type.vector.
517 ** Python's atexit.register now works in GDB.
519 ** Types can be pretty-printed via a Python API.
521 ** Python 3 is now supported (in addition to Python 2.4 or later)
523 ** New class gdb.Architecture exposes GDB's internal representation
524 of architecture in the Python API.
526 ** New method Frame.architecture returns the gdb.Architecture object
527 corresponding to the frame's architecture.
529 * New Python-based convenience functions:
531 ** $_memeq(buf1, buf2, length)
532 ** $_streq(str1, str2)
534 ** $_regex(str, regex)
536 * The 'cd' command now defaults to using '~' (the home directory) if not
539 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
540 default for GCC since November 2000.
542 * The command 'forward-search' can now be abbreviated as 'fo'.
544 * The command 'info tracepoints' can now display 'installed on target'
545 or 'not installed on target' for each non-pending location of tracepoint.
547 * New configure options
549 --enable-libmcheck/--disable-libmcheck
550 By default, development versions are built with -lmcheck on hosts
551 that support it, in order to help track memory corruption issues.
552 Release versions, on the other hand, are built without -lmcheck
553 by default. The --enable-libmcheck/--disable-libmcheck configure
554 options allow the user to override that default.
555 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
556 This configure option allows the user to build GDB with
557 libbabeltrace using which GDB can read Common Trace Format data.
559 * New commands (for set/show, see "New options" below)
562 Catch signals. This is similar to "handle", but allows commands and
563 conditions to be attached.
566 List the BFDs known to GDB.
568 python-interactive [command]
570 Start a Python interactive prompt, or evaluate the optional command
571 and print the result of expressions.
574 "py" is a new alias for "python".
576 enable type-printer [name]...
577 disable type-printer [name]...
578 Enable or disable type printers.
582 ** For the Renesas Super-H architecture, the "regs" command has been removed
583 (has been deprecated in GDB 7.5), and "info all-registers" should be used
588 set print type methods (on|off)
589 show print type methods
590 Control whether method declarations are displayed by "ptype".
591 The default is to show them.
593 set print type typedefs (on|off)
594 show print type typedefs
595 Control whether typedef definitions are displayed by "ptype".
596 The default is to show them.
598 set filename-display basename|relative|absolute
599 show filename-display
600 Control the way in which filenames is displayed.
601 The default is "relative", which preserves previous behavior.
603 set trace-buffer-size
604 show trace-buffer-size
605 Request target to change the size of trace buffer.
607 set remote trace-buffer-size-packet auto|on|off
608 show remote trace-buffer-size-packet
609 Control the use of the remote protocol `QTBuffer:size' packet.
613 Control display of debugging messages related to ARM AArch64.
616 set debug coff-pe-read
617 show debug coff-pe-read
618 Control display of debugging messages related to reading of COFF/PE
623 Control display of debugging messages related to Mach-O symbols
626 set debug notification
627 show debug notification
628 Control display of debugging info for async remote notification.
632 ** Command parameter changes are now notified using new async record
633 "=cmd-param-changed".
634 ** Trace frame changes caused by command "tfind" are now notified using
635 new async record "=traceframe-changed".
636 ** The creation, deletion and modification of trace state variables
637 are now notified using new async records "=tsv-created",
638 "=tsv-deleted" and "=tsv-modified".
639 ** The start and stop of process record are now notified using new
640 async record "=record-started" and "=record-stopped".
641 ** Memory changes are now notified using new async record
643 ** The data-disassemble command response will include a "fullname" field
644 containing the absolute file name when source has been requested.
645 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
646 command, to allow pattern filling of memory areas.
647 ** New commands "-catch-load"/"-catch-unload" added for intercepting
648 library load/unload events.
649 ** The response to breakpoint commands and breakpoint async records
650 includes an "installed" field containing a boolean state about each
651 non-pending tracepoint location is whether installed on target or not.
652 ** Output of the "-trace-status" command includes a "trace-file" field
653 containing the name of the trace file being examined. This field is
654 optional, and only present when examining a trace file.
655 ** The "fullname" field is now always present along with the "file" field,
656 even if the file cannot be found by GDB.
658 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
659 You must have the LZMA library available when configuring GDB for this
660 feature to be enabled. For more information, see:
661 http://fedoraproject.org/wiki/Features/MiniDebugInfo
666 Set the size of trace buffer. The remote stub reports support for this
667 packet to gdb's qSupported query.
670 Enable Branch Trace Store (BTS)-based branch tracing for the current
671 thread. The remote stub reports support for this packet to gdb's
675 Disable branch tracing for the current thread. The remote stub reports
676 support for this packet to gdb's qSupported query.
679 Read the traced branches for the current thread. The remote stub
680 reports support for this packet to gdb's qSupported query.
682 *** Changes in GDB 7.5
684 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
685 for more x32 ABI info.
687 * GDB now supports access to MIPS DSP registers on Linux targets.
689 * GDB now supports debugging microMIPS binaries.
691 * The "info os" command on GNU/Linux can now display information on
692 several new classes of objects managed by the operating system:
693 "info os procgroups" lists process groups
694 "info os files" lists file descriptors
695 "info os sockets" lists internet-domain sockets
696 "info os shm" lists shared-memory regions
697 "info os semaphores" lists semaphores
698 "info os msg" lists message queues
699 "info os modules" lists loaded kernel modules
701 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
702 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
703 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
704 options and inspect the probe arguments using the new $_probe_arg family
705 of convenience variables. You can obtain more information about SystemTap
706 in <http://sourceware.org/systemtap/>.
708 * GDB now supports reversible debugging on ARM, it allows you to
709 debug basic ARM and THUMB instructions, and provides
710 record/replay support.
712 * The option "symbol-reloading" has been deleted as it is no longer used.
716 ** GDB commands implemented in Python can now be put in command class
719 ** The "maint set python print-stack on|off" is now deleted.
721 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
722 apply "flag enum"-style pretty-printing to any enum.
724 ** gdb.lookup_symbol can now work when there is no current frame.
726 ** gdb.Symbol now has a 'line' attribute, holding the line number in
727 the source at which the symbol was defined.
729 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
730 method 'value'. The former indicates whether the symbol needs a
731 frame in order to compute its value, and the latter computes the
734 ** A new method 'referenced_value' on gdb.Value objects which can
735 dereference pointer as well as C++ reference values.
737 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
738 which return the global and static blocks (as gdb.Block objects),
739 of the underlying symbol table, respectively.
741 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
742 object associated with a PC value.
744 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
745 of the address range occupied by code for the current source line.
747 * Go language support.
748 GDB now supports debugging programs written in the Go programming
751 * GDBserver now supports stdio connections.
752 E.g. (gdb) target remote | ssh myhost gdbserver - hello
754 * The binary "gdbtui" can no longer be built or installed.
755 Use "gdb -tui" instead.
757 * GDB will now print "flag" enums specially. A flag enum is one where
758 all the enumerator values have no bits in common when pairwise
759 "and"ed. When printing a value whose type is a flag enum, GDB will
760 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
761 (gdb) print (enum E) 3
764 * The filename part of a linespec will now match trailing components
765 of a source file name. For example, "break gcc/expr.c:1000" will
766 now set a breakpoint in build/gcc/expr.c, but not
769 * The "info proc" and "generate-core-file" commands will now also
770 work on remote targets connected to GDBserver on Linux.
772 * The command "info catch" has been removed. It has been disabled
775 * The "catch exception" and "catch assert" commands now accept
776 a condition at the end of the command, much like the "break"
777 command does. For instance:
779 (gdb) catch exception Constraint_Error if Barrier = True
781 Previously, it was possible to add a condition to such catchpoints,
782 but it had to be done as a second step, after the catchpoint had been
783 created, using the "condition" command.
785 * The "info static-tracepoint-marker" command will now also work on
786 native Linux targets with in-process agent.
788 * GDB can now set breakpoints on inlined functions.
790 * The .gdb_index section has been updated to include symbols for
791 inlined functions. GDB will ignore older .gdb_index sections by
792 default, which could cause symbol files to be loaded more slowly
793 until their .gdb_index sections can be recreated. The new command
794 "set use-deprecated-index-sections on" will cause GDB to use any older
795 .gdb_index sections it finds. This will restore performance, but the
796 ability to set breakpoints on inlined functions will be lost in symbol
797 files with older .gdb_index sections.
799 The .gdb_index section has also been updated to record more information
800 about each symbol. This speeds up the "info variables", "info functions"
801 and "info types" commands when used with programs having the .gdb_index
802 section, as well as speeding up debugging with shared libraries using
803 the .gdb_index section.
805 * Ada support for GDB/MI Variable Objects has been added.
807 * GDB can now support 'breakpoint always-inserted mode' in 'record'
812 ** New command -info-os is the MI equivalent of "info os".
814 ** Output logs ("set logging" and related) now include MI output.
818 ** "set use-deprecated-index-sections on|off"
819 "show use-deprecated-index-sections on|off"
820 Controls the use of deprecated .gdb_index sections.
822 ** "catch load" and "catch unload" can be used to stop when a shared
823 library is loaded or unloaded, respectively.
825 ** "enable count" can be used to auto-disable a breakpoint after
828 ** "info vtbl" can be used to show the virtual method tables for
829 C++ and Java objects.
831 ** "explore" and its sub commands "explore value" and "explore type"
832 can be used to recursively explore values and types of
833 expressions. These commands are available only if GDB is
834 configured with '--with-python'.
836 ** "info auto-load" shows status of all kinds of auto-loaded files,
837 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
838 sequences of commands files, "info auto-load python-scripts"
839 shows status of auto-loading Python script files,
840 "info auto-load local-gdbinit" shows status of loading init file
841 (.gdbinit) from current directory and "info auto-load libthread-db" shows
842 status of inferior specific thread debugging shared library loading.
844 ** "info auto-load-scripts", "set auto-load-scripts on|off"
845 and "show auto-load-scripts" commands have been deprecated, use their
846 "info auto-load python-scripts", "set auto-load python-scripts on|off"
847 and "show auto-load python-scripts" counterparts instead.
849 ** "dprintf location,format,args..." creates a dynamic printf, which
850 is basically a breakpoint that does a printf and immediately
851 resumes your program's execution, so it is like a printf that you
852 can insert dynamically at runtime instead of at compiletime.
854 ** "set print symbol"
856 Controls whether GDB attempts to display the symbol, if any,
857 corresponding to addresses it prints. This defaults to "on", but
858 you can set it to "off" to restore GDB's previous behavior.
860 * Deprecated commands
862 ** For the Renesas Super-H architecture, the "regs" command has been
863 deprecated, and "info all-registers" should be used instead.
867 Renesas RL78 rl78-*-elf
868 HP OpenVMS ia64 ia64-hp-openvms*
870 * GDBserver supports evaluation of breakpoint conditions. When
871 support is advertised by GDBserver, GDB may be told to send the
872 breakpoint conditions in bytecode form to GDBserver. GDBserver
873 will only report the breakpoint trigger to GDB when its condition
879 show mips compression
880 Select the compressed ISA encoding used in functions that have no symbol
881 information available. The encoding can be set to either of:
884 and is updated automatically from ELF file flags if available.
886 set breakpoint condition-evaluation
887 show breakpoint condition-evaluation
888 Control whether breakpoint conditions are evaluated by GDB ("host") or by
889 GDBserver ("target"). Default option "auto" chooses the most efficient
891 This option can improve debugger efficiency depending on the speed of the
895 Disable auto-loading globally.
898 Show auto-loading setting of all kinds of auto-loaded files.
900 set auto-load gdb-scripts on|off
901 show auto-load gdb-scripts
902 Control auto-loading of GDB canned sequences of commands files.
904 set auto-load python-scripts on|off
905 show auto-load python-scripts
906 Control auto-loading of Python script files.
908 set auto-load local-gdbinit on|off
909 show auto-load local-gdbinit
910 Control loading of init file (.gdbinit) from current directory.
912 set auto-load libthread-db on|off
913 show auto-load libthread-db
914 Control auto-loading of inferior specific thread debugging shared library.
916 set auto-load scripts-directory <dir1>[:<dir2>...]
917 show auto-load scripts-directory
918 Set a list of directories from which to load auto-loaded scripts.
919 Automatically loaded Python scripts and GDB scripts are located in one
920 of the directories listed by this option.
921 The delimiter (':' above) may differ according to the host platform.
923 set auto-load safe-path <dir1>[:<dir2>...]
924 show auto-load safe-path
925 Set a list of directories from which it is safe to auto-load files.
926 The delimiter (':' above) may differ according to the host platform.
928 set debug auto-load on|off
930 Control display of debugging info for auto-loading the files above.
932 set dprintf-style gdb|call|agent
934 Control the way in which a dynamic printf is performed; "gdb"
935 requests a GDB printf command, while "call" causes dprintf to call a
936 function in the inferior. "agent" requests that the target agent
937 (such as GDBserver) do the printing.
939 set dprintf-function <expr>
940 show dprintf-function
941 set dprintf-channel <expr>
943 Set the function and optional first argument to the call when using
944 the "call" style of dynamic printf.
946 set disconnected-dprintf on|off
947 show disconnected-dprintf
948 Control whether agent-style dynamic printfs continue to be in effect
949 after GDB disconnects.
951 * New configure options
954 Configure default value for the 'set auto-load scripts-directory'
955 setting above. It defaults to '$debugdir:$datadir/auto-load',
956 $debugdir representing global debugging info directories (available
957 via 'show debug-file-directory') and $datadir representing GDB's data
958 directory (available via 'show data-directory').
960 --with-auto-load-safe-path
961 Configure default value for the 'set auto-load safe-path' setting
962 above. It defaults to the --with-auto-load-dir setting.
964 --without-auto-load-safe-path
965 Set 'set auto-load safe-path' to '/', effectively disabling this
970 z0/z1 conditional breakpoints extension
972 The z0/z1 breakpoint insertion packets have been extended to carry
973 a list of conditional expressions over to the remote stub depending on the
974 condition evaluation mode. The use of this extension can be controlled
975 via the "set remote conditional-breakpoints-packet" command.
979 Specify the signals which the remote stub may pass to the debugged
980 program without GDB involvement.
982 * New command line options
984 --init-command=FILE, -ix Like --command, -x but execute it
985 before loading inferior.
986 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
987 execute it before loading inferior.
989 *** Changes in GDB 7.4
991 * GDB now handles ambiguous linespecs more consistently; the existing
992 FILE:LINE support has been expanded to other types of linespecs. A
993 breakpoint will now be set on all matching locations in all
994 inferiors, and locations will be added or removed according to
997 * GDB now allows you to skip uninteresting functions and files when
998 stepping with the "skip function" and "skip file" commands.
1000 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1001 and "show remote hardware-watchpoint-length-limit". These allows to
1002 set or show the maximum length limit (in bytes) of a remote
1003 target hardware watchpoint.
1005 This allows e.g. to use "unlimited" hardware watchpoints with the
1006 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1007 watchpoints are slower than real hardware watchpoints but are
1008 significantly faster than gdb software watchpoints.
1012 ** The register_pretty_printer function in module gdb.printing now takes
1013 an optional `replace' argument. If True, the new printer replaces any
1016 ** The "maint set python print-stack on|off" command has been
1017 deprecated and will be deleted in GDB 7.5.
1018 A new command: "set python print-stack none|full|message" has
1019 replaced it. Additionally, the default for "print-stack" is
1020 now "message", which just prints the error message without
1023 ** A prompt substitution hook (prompt_hook) is now available to the
1026 ** A new Python module, gdb.prompt has been added to the GDB Python
1027 modules library. This module provides functionality for
1028 escape sequences in prompts (used by set/show
1029 extended-prompt). These escape sequences are replaced by their
1030 corresponding value.
1032 ** Python commands and convenience-functions located in
1033 'data-directory'/python/gdb/command and
1034 'data-directory'/python/gdb/function are now automatically loaded
1037 ** Blocks now provide four new attributes. global_block and
1038 static_block will return the global and static blocks
1039 respectively. is_static and is_global are boolean attributes
1040 that indicate if the block is one of those two types.
1042 ** Symbols now provide the "type" attribute, the type of the symbol.
1044 ** The "gdb.breakpoint" function has been deprecated in favor of
1047 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1048 of a function. This class is based on the "finish" command
1049 available in the CLI.
1051 ** Type objects for struct and union types now allow access to
1052 the fields using standard Python dictionary (mapping) methods.
1053 For example, "some_type['myfield']" now works, as does
1054 "some_type.items()".
1056 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1059 ** A new function, "deep_items" has been added to the gdb.types
1060 module in the GDB Python modules library. This function returns
1061 an iterator over the fields of a struct or union type. Unlike
1062 the standard Python "iteritems" method, it will recursively traverse
1063 any anonymous fields.
1067 ** "*stopped" events can report several new "reason"s, such as
1070 ** Breakpoint changes are now notified using new async records, like
1071 "=breakpoint-modified".
1073 ** New command -ada-task-info.
1075 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1076 $sdir specifies the default system locations of shared libraries.
1077 $pdir specifies the directory where the libpthread used by the application
1080 GDB no longer looks in $sdir and $pdir after it has searched the directories
1081 mentioned in libthread-db-search-path. If you want to search those
1082 directories, they must be specified in libthread-db-search-path.
1083 The default value of libthread-db-search-path on GNU/Linux and Solaris
1084 systems is now "$sdir:$pdir".
1086 $pdir is not supported by gdbserver, it is currently ignored.
1087 $sdir is supported by gdbserver.
1089 * New configure option --with-iconv-bin.
1090 When using the internationalization support like the one in the GNU C
1091 library, GDB will invoke the "iconv" program to get a list of supported
1092 character sets. If this program lives in a non-standard location, one can
1093 use this option to specify where to find it.
1095 * When natively debugging programs on PowerPC BookE processors running
1096 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1097 watchpoints, which specify a mask in addition to an address to watch.
1098 The mask specifies that some bits of an address (the bits which are
1099 reset in the mask) should be ignored when matching the address accessed
1100 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1101 section in the user manual for more details.
1103 * The new option --once causes GDBserver to stop listening for connections once
1104 the first connection is made. The listening port used by GDBserver will
1105 become available after that.
1107 * New commands "info macros" and "alias" have been added.
1109 * New function parameters suffix @entry specifies value of function parameter
1110 at the time the function got called. Entry values are available only since
1116 "!" is now an alias of the "shell" command.
1117 Note that no space is needed between "!" and SHELL COMMAND.
1121 watch EXPRESSION mask MASK_VALUE
1122 The watch command now supports the mask argument which allows creation
1123 of masked watchpoints, if the current architecture supports this feature.
1125 info auto-load-scripts [REGEXP]
1126 This command was formerly named "maintenance print section-scripts".
1127 It is now generally useful and is no longer a maintenance-only command.
1129 info macro [-all] [--] MACRO
1130 The info macro command has new options `-all' and `--'. The first for
1131 printing all definitions of a macro. The second for explicitly specifying
1132 the end of arguments and the beginning of the macro name in case the macro
1133 name starts with a hyphen.
1135 collect[/s] EXPRESSIONS
1136 The tracepoint collect command now takes an optional modifier "/s"
1137 that directs it to dereference pointer-to-character types and
1138 collect the bytes of memory up to a zero byte. The behavior is
1139 similar to what you see when you use the regular print command on a
1140 string. An optional integer following the "/s" sets a bound on the
1141 number of bytes that will be collected.
1144 The trace start command now interprets any supplied arguments as a
1145 note to be recorded with the trace run, with an effect similar to
1146 setting the variable trace-notes.
1149 The trace stop command now interprets any arguments as a note to be
1150 mentioned along with the tstatus report that the trace was stopped
1151 with a command. The effect is similar to setting the variable
1154 * Tracepoints can now be enabled and disabled at any time after a trace
1155 experiment has been started using the standard "enable" and "disable"
1156 commands. It is now possible to start a trace experiment with no enabled
1157 tracepoints; GDB will display a warning, but will allow the experiment to
1158 begin, assuming that tracepoints will be enabled as needed while the trace
1161 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1162 locations with 4-byte instructions, when they were previously
1163 limited to locations with instructions of 5 bytes or longer.
1167 set debug dwarf2-read
1168 show debug dwarf2-read
1169 Turns on or off display of debugging messages related to reading
1170 DWARF debug info. The default is off.
1172 set debug symtab-create
1173 show debug symtab-create
1174 Turns on or off display of debugging messages related to symbol table
1175 creation. The default is off.
1178 show extended-prompt
1179 Set the GDB prompt, and allow escape sequences to be inserted to
1180 display miscellaneous information (see 'help set extended-prompt'
1181 for the list of sequences). This prompt (and any information
1182 accessed through the escape sequences) is updated every time the
1183 prompt is displayed.
1185 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1186 show print entry-values
1187 Set printing of frame argument values at function entry. In some cases
1188 GDB can determine the value of function argument which was passed by the
1189 function caller, even if the value was modified inside the called function.
1191 set debug entry-values
1192 show debug entry-values
1193 Control display of debugging info for determining frame argument values at
1194 function entry and virtual tail call frames.
1196 set basenames-may-differ
1197 show basenames-may-differ
1198 Set whether a source file may have multiple base names.
1199 (A "base name" is the name of a file with the directory part removed.
1200 Example: The base name of "/home/user/hello.c" is "hello.c".)
1201 If set, GDB will canonicalize file names (e.g., expand symlinks)
1202 before comparing them. Canonicalization is an expensive operation,
1203 but it allows the same file be known by more than one base name.
1204 If not set (the default), all source files are assumed to have just
1205 one base name, and gdb will do file name comparisons more efficiently.
1211 Set a user name and notes for the current and any future trace runs.
1212 This is useful for long-running and/or disconnected traces, to
1213 inform others (or yourself) as to who is running the trace, supply
1214 contact information, or otherwise explain what is going on.
1216 set trace-stop-notes
1217 show trace-stop-notes
1218 Set a note attached to the trace run, that is displayed when the
1219 trace has been stopped by a tstop command. This is useful for
1220 instance as an explanation, if you are stopping a trace run that was
1221 started by someone else.
1223 * New remote packets
1227 Dynamically enable a tracepoint in a started trace experiment.
1231 Dynamically disable a tracepoint in a started trace experiment.
1235 Set the user and notes of the trace run.
1239 Query the current status of a tracepoint.
1243 Query the minimum length of instruction at which a fast tracepoint may
1246 * Dcache size (number of lines) and line-size are now runtime-configurable
1247 via "set dcache line" and "set dcache line-size" commands.
1251 Texas Instruments TMS320C6x tic6x-*-*
1255 Renesas RL78 rl78-*-elf
1257 *** Changes in GDB 7.3.1
1259 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1261 *** Changes in GDB 7.3
1263 * GDB has a new command: "thread find [REGEXP]".
1264 It finds the thread id whose name, target id, or thread extra info
1265 matches the given regular expression.
1267 * The "catch syscall" command now works on mips*-linux* targets.
1269 * The -data-disassemble MI command now supports modes 2 and 3 for
1270 dumping the instruction opcodes.
1272 * New command line options
1274 -data-directory DIR Specify DIR as the "data-directory".
1275 This is mostly for testing purposes.
1277 * The "maint set python auto-load on|off" command has been renamed to
1278 "set auto-load-scripts on|off".
1280 * GDB has a new command: "set directories".
1281 It is like the "dir" command except that it replaces the
1282 source path list instead of augmenting it.
1284 * GDB now understands thread names.
1286 On GNU/Linux, "info threads" will display the thread name as set by
1287 prctl or pthread_setname_np.
1289 There is also a new command, "thread name", which can be used to
1290 assign a name internally for GDB to display.
1293 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1294 has been integrated into GDB.
1298 ** The function gdb.Write now accepts an optional keyword 'stream'.
1299 This keyword, when provided, will direct the output to either
1300 stdout, stderr, or GDB's logging output.
1302 ** Parameters can now be be sub-classed in Python, and in particular
1303 you may implement the get_set_doc and get_show_doc functions.
1304 This improves how Parameter set/show documentation is processed
1305 and allows for more dynamic content.
1307 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1308 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1309 have an is_valid method.
1311 ** Breakpoints can now be sub-classed in Python, and in particular
1312 you may implement a 'stop' function that is executed each time
1313 the inferior reaches that breakpoint.
1315 ** New function gdb.lookup_global_symbol looks up a global symbol.
1317 ** GDB values in Python are now callable if the value represents a
1318 function. For example, if 'some_value' represents a function that
1319 takes two integer parameters and returns a value, you can call
1320 that function like so:
1322 result = some_value (10,20)
1324 ** Module gdb.types has been added.
1325 It contains a collection of utilities for working with gdb.Types objects:
1326 get_basic_type, has_field, make_enum_dict.
1328 ** Module gdb.printing has been added.
1329 It contains utilities for writing and registering pretty-printers.
1330 New classes: PrettyPrinter, SubPrettyPrinter,
1331 RegexpCollectionPrettyPrinter.
1332 New function: register_pretty_printer.
1334 ** New commands "info pretty-printers", "enable pretty-printer" and
1335 "disable pretty-printer" have been added.
1337 ** gdb.parameter("directories") is now available.
1339 ** New function gdb.newest_frame returns the newest frame in the
1342 ** The gdb.InferiorThread class has a new "name" attribute. This
1343 holds the thread's name.
1345 ** Python Support for Inferior events.
1346 Python scripts can add observers to be notified of events
1347 occurring in the process being debugged.
1348 The following events are currently supported:
1349 - gdb.events.cont Continue event.
1350 - gdb.events.exited Inferior exited event.
1351 - gdb.events.stop Signal received, and Breakpoint hit events.
1355 ** GDB now puts template parameters in scope when debugging in an
1356 instantiation. For example, if you have:
1358 template<int X> int func (void) { return X; }
1360 then if you step into func<5>, "print X" will show "5". This
1361 feature requires proper debuginfo support from the compiler; it
1362 was added to GCC 4.5.
1364 ** The motion commands "next", "finish", "until", and "advance" now
1365 work better when exceptions are thrown. In particular, GDB will
1366 no longer lose control of the inferior; instead, the GDB will
1367 stop the inferior at the point at which the exception is caught.
1368 This functionality requires a change in the exception handling
1369 code that was introduced in GCC 4.5.
1371 * GDB now follows GCC's rules on accessing volatile objects when
1372 reading or writing target state during expression evaluation.
1373 One notable difference to prior behavior is that "print x = 0"
1374 no longer generates a read of x; the value of the assignment is
1375 now always taken directly from the value being assigned.
1377 * GDB now has some support for using labels in the program's source in
1378 linespecs. For instance, you can use "advance label" to continue
1379 execution to a label.
1381 * GDB now has support for reading and writing a new .gdb_index
1382 section. This section holds a fast index of DWARF debugging
1383 information and can be used to greatly speed up GDB startup and
1384 operation. See the documentation for `save gdb-index' for details.
1386 * The "watch" command now accepts an optional "-location" argument.
1387 When used, this causes GDB to watch the memory referred to by the
1388 expression. Such a watchpoint is never deleted due to it going out
1391 * GDB now supports thread debugging of core dumps on GNU/Linux.
1393 GDB now activates thread debugging using the libthread_db library
1394 when debugging GNU/Linux core dumps, similarly to when debugging
1395 live processes. As a result, when debugging a core dump file, GDB
1396 is now able to display pthread_t ids of threads. For example, "info
1397 threads" shows the same output as when debugging the process when it
1398 was live. In earlier releases, you'd see something like this:
1401 * 1 LWP 6780 main () at main.c:10
1403 While now you see this:
1406 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1408 It is also now possible to inspect TLS variables when debugging core
1411 When debugging a core dump generated on a machine other than the one
1412 used to run GDB, you may need to point GDB at the correct
1413 libthread_db library with the "set libthread-db-search-path"
1414 command. See the user manual for more details on this command.
1416 * When natively debugging programs on PowerPC BookE processors running
1417 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1418 which stop execution of the inferior whenever it executes an instruction
1419 at any address within the specified range. See the "PowerPC Embedded"
1420 section in the user manual for more details.
1422 * New features in the GDB remote stub, GDBserver
1424 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1425 and i686 LynxOS (version 5.x).
1427 ** GDBserver is now supported on Blackfin Linux.
1429 * New native configurations
1431 ia64 HP-UX ia64-*-hpux*
1435 Analog Devices, Inc. Blackfin Processor bfin-*
1437 * Ada task switching is now supported on sparc-elf targets when
1438 debugging a program using the Ravenscar Profile. For more information,
1439 see the "Tasking Support when using the Ravenscar Profile" section
1440 in the GDB user manual.
1442 * Guile support was removed.
1444 * New features in the GNU simulator
1446 ** The --map-info flag lists all known core mappings.
1448 ** CFI flashes may be simulated via the "cfi" device.
1450 *** Changes in GDB 7.2
1452 * Shared library support for remote targets by default
1454 When GDB is configured for a generic, non-OS specific target, like
1455 for example, --target=arm-eabi or one of the many *-*-elf targets,
1456 GDB now queries remote stubs for loaded shared libraries using the
1457 `qXfer:libraries:read' packet. Previously, shared library support
1458 was always disabled for such configurations.
1462 ** Argument Dependent Lookup (ADL)
1464 In C++ ADL lookup directs function search to the namespaces of its
1465 arguments even if the namespace has not been imported.
1475 Here the compiler will search for `foo' in the namespace of 'b'
1476 and find A::foo. GDB now supports this. This construct is commonly
1477 used in the Standard Template Library for operators.
1479 ** Improved User Defined Operator Support
1481 In addition to member operators, GDB now supports lookup of operators
1482 defined in a namespace and imported with a `using' directive, operators
1483 defined in the global scope, operators imported implicitly from an
1484 anonymous namespace, and the ADL operators mentioned in the previous
1486 GDB now also supports proper overload resolution for all the previously
1487 mentioned flavors of operators.
1489 ** static const class members
1491 Printing of static const class members that are initialized in the
1492 class definition has been fixed.
1494 * Windows Thread Information Block access.
1496 On Windows targets, GDB now supports displaying the Windows Thread
1497 Information Block (TIB) structure. This structure is visible either
1498 by using the new command `info w32 thread-information-block' or, by
1499 dereferencing the new convenience variable named `$_tlb', a
1500 thread-specific pointer to the TIB. This feature is also supported
1501 when remote debugging using GDBserver.
1503 * Static tracepoints
1505 Static tracepoints are calls in the user program into a tracing
1506 library. One such library is a port of the LTTng kernel tracer to
1507 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1508 When debugging with GDBserver, GDB now supports combining the GDB
1509 tracepoint machinery with such libraries. For example: the user can
1510 use GDB to probe a static tracepoint marker (a call from the user
1511 program into the tracing library) with the new "strace" command (see
1512 "New commands" below). This creates a "static tracepoint" in the
1513 breakpoint list, that can be manipulated with the same feature set
1514 as fast and regular tracepoints. E.g., collect registers, local and
1515 global variables, collect trace state variables, and define
1516 tracepoint conditions. In addition, the user can collect extra
1517 static tracepoint marker specific data, by collecting the new
1518 $_sdata internal variable. When analyzing the trace buffer, you can
1519 inspect $_sdata like any other variable available to GDB. For more
1520 information, see the "Tracepoints" chapter in GDB user manual. New
1521 remote packets have been defined to support static tracepoints, see
1522 the "New remote packets" section below.
1524 * Better reconstruction of tracepoints after disconnected tracing
1526 GDB will attempt to download the original source form of tracepoint
1527 definitions when starting a trace run, and then will upload these
1528 upon reconnection to the target, resulting in a more accurate
1529 reconstruction of the tracepoints that are in use on the target.
1533 You can now exercise direct control over the ways that GDB can
1534 affect your program. For instance, you can disallow the setting of
1535 breakpoints, so that the program can run continuously (assuming
1536 non-stop mode). In addition, the "observer" variable is available
1537 to switch all of the different controls; in observer mode, GDB
1538 cannot affect the target's behavior at all, which is useful for
1539 tasks like diagnosing live systems in the field.
1541 * The new convenience variable $_thread holds the number of the
1544 * New remote packets
1548 Return the address of the Windows Thread Information Block of a given thread.
1552 In response to several of the tracepoint packets, the target may now
1553 also respond with a number of intermediate `qRelocInsn' request
1554 packets before the final result packet, to have GDB handle
1555 relocating an instruction to execute at a different address. This
1556 is particularly useful for stubs that support fast tracepoints. GDB
1557 reports support for this feature in the qSupported packet.
1561 List static tracepoint markers in the target program.
1565 List static tracepoint markers at a given address in the target
1568 qXfer:statictrace:read
1570 Read the static trace data collected (by a `collect $_sdata'
1571 tracepoint action). The remote stub reports support for this packet
1572 to gdb's qSupported query.
1576 Send the current settings of GDB's permission flags.
1580 Send part of the source (textual) form of a tracepoint definition,
1581 which includes location, conditional, and action list.
1583 * The source command now accepts a -s option to force searching for the
1584 script in the source search path even if the script name specifies
1587 * New features in the GDB remote stub, GDBserver
1589 - GDBserver now support tracepoints (including fast tracepoints, and
1590 static tracepoints). The feature is currently supported by the
1591 i386-linux and amd64-linux builds. See the "Tracepoints support
1592 in gdbserver" section in the manual for more information.
1594 GDBserver JIT compiles the tracepoint's conditional agent
1595 expression bytecode into native code whenever possible for low
1596 overhead dynamic tracepoints conditionals. For such tracepoints,
1597 an expression that examines program state is evaluated when the
1598 tracepoint is reached, in order to determine whether to capture
1599 trace data. If the condition is simple and false, processing the
1600 tracepoint finishes very quickly and no data is gathered.
1602 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1603 for static tracepoints support.
1605 - GDBserver now supports x86_64 Windows 64-bit debugging.
1607 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1608 it understands register description.
1610 * The --batch flag now disables pagination and queries.
1612 * X86 general purpose registers
1614 GDB now supports reading/writing byte, word and double-word x86
1615 general purpose registers directly. This means you can use, say,
1616 $ah or $ax to refer, respectively, to the byte register AH and
1617 16-bit word register AX that are actually portions of the 32-bit
1618 register EAX or 64-bit register RAX.
1620 * The `commands' command now accepts a range of breakpoints to modify.
1621 A plain `commands' following a command that creates multiple
1622 breakpoints affects all the breakpoints set by that command. This
1623 applies to breakpoints set by `rbreak', and also applies when a
1624 single `break' command creates multiple breakpoints (e.g.,
1625 breakpoints on overloaded c++ functions).
1627 * The `rbreak' command now accepts a filename specification as part of
1628 its argument, limiting the functions selected by the regex to those
1629 in the specified file.
1631 * Support for remote debugging Windows and SymbianOS shared libraries
1632 from Unix hosts has been improved. Non Windows GDB builds now can
1633 understand target reported file names that follow MS-DOS based file
1634 system semantics, such as file names that include drive letters and
1635 use the backslash character as directory separator. This makes it
1636 possible to transparently use the "set sysroot" and "set
1637 solib-search-path" on Unix hosts to point as host copies of the
1638 target's shared libraries. See the new command "set
1639 target-file-system-kind" described below, and the "Commands to
1640 specify files" section in the user manual for more information.
1644 eval template, expressions...
1645 Convert the values of one or more expressions under the control
1646 of the string template to a command line, and call it.
1648 set target-file-system-kind unix|dos-based|auto
1649 show target-file-system-kind
1650 Set or show the assumed file system kind for target reported file
1653 save breakpoints <filename>
1654 Save all current breakpoint definitions to a file suitable for use
1655 in a later debugging session. To read the saved breakpoint
1656 definitions, use the `source' command.
1658 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1661 info static-tracepoint-markers
1662 Display information about static tracepoint markers in the target.
1664 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1665 Define a static tracepoint by probing a marker at the given
1666 function, line, address, or marker ID.
1670 Enable and disable observer mode.
1672 set may-write-registers on|off
1673 set may-write-memory on|off
1674 set may-insert-breakpoints on|off
1675 set may-insert-tracepoints on|off
1676 set may-insert-fast-tracepoints on|off
1677 set may-interrupt on|off
1678 Set individual permissions for GDB effects on the target. Note that
1679 some of these settings can have undesirable or surprising
1680 consequences, particularly when changed in the middle of a session.
1681 For instance, disabling the writing of memory can prevent
1682 breakpoints from being inserted, cause single-stepping to fail, or
1683 even crash your program, if you disable after breakpoints have been
1684 inserted. However, GDB should not crash.
1686 set record memory-query on|off
1687 show record memory-query
1688 Control whether to stop the inferior if memory changes caused
1689 by an instruction cannot be recorded.
1694 The disassemble command now supports "start,+length" form of two arguments.
1698 ** GDB now provides a new directory location, called the python directory,
1699 where Python scripts written for GDB can be installed. The location
1700 of that directory is <data-directory>/python, where <data-directory>
1701 is the GDB data directory. For more details, see section `Scripting
1702 GDB using Python' in the manual.
1704 ** The GDB Python API now has access to breakpoints, symbols, symbol
1705 tables, program spaces, inferiors, threads and frame's code blocks.
1706 Additionally, GDB Parameters can now be created from the API, and
1707 manipulated via set/show in the CLI.
1709 ** New functions gdb.target_charset, gdb.target_wide_charset,
1710 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1712 ** New exception gdb.GdbError.
1714 ** Pretty-printers are now also looked up in the current program space.
1716 ** Pretty-printers can now be individually enabled and disabled.
1718 ** GDB now looks for names of Python scripts to auto-load in a
1719 special section named `.debug_gdb_scripts', in addition to looking
1720 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1722 * Tracepoint actions were unified with breakpoint commands. In particular,
1723 there are no longer differences in "info break" output for breakpoints and
1724 tracepoints and the "commands" command can be used for both tracepoints and
1725 regular breakpoints.
1729 ARM Symbian arm*-*-symbianelf*
1731 * D language support.
1732 GDB now supports debugging programs written in the D programming
1735 * GDB now supports the extended ptrace interface for PowerPC which is
1736 available since Linux kernel version 2.6.34. This automatically enables
1737 any hardware breakpoints and additional hardware watchpoints available in
1738 the processor. The old ptrace interface exposes just one hardware
1739 watchpoint and no hardware breakpoints.
1741 * GDB is now able to use the Data Value Compare (DVC) register available on
1742 embedded PowerPC processors to implement in hardware simple watchpoint
1743 conditions of the form:
1745 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1747 This works in native GDB running on Linux kernels with the extended ptrace
1748 interface mentioned above.
1750 *** Changes in GDB 7.1
1754 ** Namespace Support
1756 GDB now supports importing of namespaces in C++. This enables the
1757 user to inspect variables from imported namespaces. Support for
1758 namepace aliasing has also been added. So, if a namespace is
1759 aliased in the current scope (e.g. namepace C=A; ) the user can
1760 print variables using the alias (e.g. (gdb) print C::x).
1764 All known bugs relating to the printing of virtual base class were
1765 fixed. It is now possible to call overloaded static methods using a
1770 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1771 and reinterpret_cast<> are now handled by the C++ expression parser.
1775 Xilinx MicroBlaze microblaze-*-*
1780 Xilinx MicroBlaze microblaze
1783 * Multi-program debugging.
1785 GDB now has support for multi-program (a.k.a. multi-executable or
1786 multi-exec) debugging. This allows for debugging multiple inferiors
1787 simultaneously each running a different program under the same GDB
1788 session. See "Debugging Multiple Inferiors and Programs" in the
1789 manual for more information. This implied some user visible changes
1790 in the multi-inferior support. For example, "info inferiors" now
1791 lists inferiors that are not running yet or that have exited
1792 already. See also "New commands" and "New options" below.
1794 * New tracing features
1796 GDB's tracepoint facility now includes several new features:
1798 ** Trace state variables
1800 GDB tracepoints now include support for trace state variables, which
1801 are variables managed by the target agent during a tracing
1802 experiment. They are useful for tracepoints that trigger each
1803 other, so for instance one tracepoint can count hits in a variable,
1804 and then a second tracepoint has a condition that is true when the
1805 count reaches a particular value. Trace state variables share the
1806 $-syntax of GDB convenience variables, and can appear in both
1807 tracepoint actions and condition expressions. Use the "tvariable"
1808 command to create, and "info tvariables" to view; see "Trace State
1809 Variables" in the manual for more detail.
1813 GDB now includes an option for defining fast tracepoints, which
1814 targets may implement more efficiently, such as by installing a jump
1815 into the target agent rather than a trap instruction. The resulting
1816 speedup can be by two orders of magnitude or more, although the
1817 tradeoff is that some program locations on some target architectures
1818 might not allow fast tracepoint installation, for instance if the
1819 instruction to be replaced is shorter than the jump. To request a
1820 fast tracepoint, use the "ftrace" command, with syntax identical to
1821 the regular trace command.
1823 ** Disconnected tracing
1825 It is now possible to detach GDB from the target while it is running
1826 a trace experiment, then reconnect later to see how the experiment
1827 is going. In addition, a new variable disconnected-tracing lets you
1828 tell the target agent whether to continue running a trace if the
1829 connection is lost unexpectedly.
1833 GDB now has the ability to save the trace buffer into a file, and
1834 then use that file as a target, similarly to you can do with
1835 corefiles. You can select trace frames, print data that was
1836 collected in them, and use tstatus to display the state of the
1837 tracing run at the moment that it was saved. To create a trace
1838 file, use "tsave <filename>", and to use it, do "target tfile
1841 ** Circular trace buffer
1843 You can ask the target agent to handle the trace buffer as a
1844 circular buffer, discarding the oldest trace frames to make room for
1845 newer ones, by setting circular-trace-buffer to on. This feature may
1846 not be available for all target agents.
1851 The disassemble command, when invoked with two arguments, now requires
1852 the arguments to be comma-separated.
1855 The info variables command now displays variable definitions. Files
1856 which only declare a variable are not shown.
1859 The source command is now capable of sourcing Python scripts.
1860 This feature is dependent on the debugger being build with Python
1863 Related to this enhancement is also the introduction of a new command
1864 "set script-extension" (see below).
1866 * New commands (for set/show, see "New options" below)
1868 record save [<FILENAME>]
1869 Save a file (in core file format) containing the process record
1870 execution log for replay debugging at a later time.
1872 record restore <FILENAME>
1873 Restore the process record execution log that was saved at an
1874 earlier time, for replay debugging.
1876 add-inferior [-copies <N>] [-exec <FILENAME>]
1879 clone-inferior [-copies <N>] [ID]
1880 Make a new inferior ready to execute the same program another
1881 inferior has loaded.
1886 maint info program-spaces
1887 List the program spaces loaded into GDB.
1889 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1890 show remote interrupt-sequence
1891 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1892 as the sequence to the remote target in order to interrupt the execution.
1893 Ctrl-C is a default. Some system prefers BREAK which is high level of
1894 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1895 Magic SysRq g. It is BREAK signal and character 'g'.
1897 set remote interrupt-on-connect [on | off]
1898 show remote interrupt-on-connect
1899 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1900 remote target when gdb connects to it. This is needed when you debug
1903 set remotebreak [on | off]
1905 Deprecated. Use "set/show remote interrupt-sequence" instead.
1907 tvariable $NAME [ = EXP ]
1908 Create or modify a trace state variable.
1911 List trace state variables and their values.
1913 delete tvariable $NAME ...
1914 Delete one or more trace state variables.
1917 Evaluate the given expressions without collecting anything into the
1918 trace buffer. (Valid in tracepoint actions only.)
1920 ftrace FN / FILE:LINE / *ADDR
1921 Define a fast tracepoint at the given function, line, or address.
1923 * New expression syntax
1925 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1926 GDB now parses 0b101010 identically with 42.
1930 set follow-exec-mode new|same
1931 show follow-exec-mode
1932 Control whether GDB reuses the same inferior across an exec call or
1933 creates a new one. This is useful to be able to restart the old
1934 executable after the inferior having done an exec call.
1936 set default-collect EXPR, ...
1937 show default-collect
1938 Define a list of expressions to be collected at each tracepoint.
1939 This is a useful way to ensure essential items are not overlooked,
1940 such as registers or a critical global variable.
1942 set disconnected-tracing
1943 show disconnected-tracing
1944 If set to 1, the target is instructed to continue tracing if it
1945 loses its connection to GDB. If 0, the target is to stop tracing
1948 set circular-trace-buffer
1949 show circular-trace-buffer
1950 If set to on, the target is instructed to use a circular trace buffer
1951 and discard the oldest trace frames instead of stopping the trace due
1952 to a full trace buffer. If set to off, the trace stops when the buffer
1953 fills up. Some targets may not support this.
1955 set script-extension off|soft|strict
1956 show script-extension
1957 If set to "off", the debugger does not perform any script language
1958 recognition, and all sourced files are assumed to be GDB scripts.
1959 If set to "soft" (the default), files are sourced according to
1960 filename extension, falling back to GDB scripts if the first
1962 If set to "strict", files are sourced according to filename extension.
1964 set ada trust-PAD-over-XVS on|off
1965 show ada trust-PAD-over-XVS
1966 If off, activate a workaround against a bug in the debugging information
1967 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1968 the GCC sources for more information about the GNAT encoding and
1969 PAD types in particular). It is always safe to set this option to
1970 off, but this introduces a slight performance penalty. The default
1973 * Python API Improvements
1975 ** GDB provides the new class gdb.LazyString. This is useful in
1976 some pretty-printing cases. The new method gdb.Value.lazy_string
1977 provides a simple way to create objects of this type.
1979 ** The fields returned by gdb.Type.fields now have an
1980 `is_base_class' attribute.
1982 ** The new method gdb.Type.range returns the range of an array type.
1984 ** The new method gdb.parse_and_eval can be used to parse and
1985 evaluate an expression.
1987 * New remote packets
1990 Define a trace state variable.
1993 Get the current value of a trace state variable.
1996 Set desired tracing behavior upon disconnection.
1999 Set the trace buffer to be linear or circular.
2002 Get data about the tracepoints currently in use.
2006 Process record now works correctly with hardware watchpoints.
2008 Multiple bug fixes have been made to the mips-irix port, making it
2009 much more reliable. In particular:
2010 - Debugging threaded applications is now possible again. Previously,
2011 GDB would hang while starting the program, or while waiting for
2012 the program to stop at a breakpoint.
2013 - Attaching to a running process no longer hangs.
2014 - An error occurring while loading a core file has been fixed.
2015 - Changing the value of the PC register now works again. This fixes
2016 problems observed when using the "jump" command, or when calling
2017 a function from GDB, or even when assigning a new value to $pc.
2018 - With the "finish" and "return" commands, the return value for functions
2019 returning a small array is now correctly printed.
2020 - It is now possible to break on shared library code which gets executed
2021 during a shared library init phase (code executed while executing
2022 their .init section). Previously, the breakpoint would have no effect.
2023 - GDB is now able to backtrace through the signal handler for
2024 non-threaded programs.
2026 PIE (Position Independent Executable) programs debugging is now supported.
2027 This includes debugging execution of PIC (Position Independent Code) shared
2028 libraries although for that, it should be possible to run such libraries as an
2031 *** Changes in GDB 7.0
2033 * GDB now has an interface for JIT compilation. Applications that
2034 dynamically generate code can create symbol files in memory and register
2035 them with GDB. For users, the feature should work transparently, and
2036 for JIT developers, the interface is documented in the GDB manual in the
2037 "JIT Compilation Interface" chapter.
2039 * Tracepoints may now be conditional. The syntax is as for
2040 breakpoints; either an "if" clause appended to the "trace" command,
2041 or the "condition" command is available. GDB sends the condition to
2042 the target for evaluation using the same bytecode format as is used
2043 for tracepoint actions.
2045 * The disassemble command now supports: an optional /r modifier, print the
2046 raw instructions in hex as well as in symbolic form, and an optional /m
2047 modifier to print mixed source+assembly.
2049 * Process record and replay
2051 In a architecture environment that supports ``process record and
2052 replay'', ``process record and replay'' target can record a log of
2053 the process execution, and replay it with both forward and reverse
2056 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2057 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2058 set execution-direction {forward|reverse}, for targets that support
2061 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2062 feature is available with a native GDB running on kernel version
2065 * GDB now has support for multi-byte and wide character sets on the
2066 target. Strings whose character type is wchar_t, char16_t, or
2067 char32_t are now correctly printed. GDB supports wide- and unicode-
2068 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2069 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2070 `printf'. This feature requires iconv to work properly; if your
2071 system does not have a working iconv, GDB can use GNU libiconv. See
2072 the installation instructions for more information.
2074 * GDB now supports automatic retrieval of shared library files from
2075 remote targets. To use this feature, specify a system root that begins
2076 with the `remote:' prefix, either via the `set sysroot' command or via
2077 the `--with-sysroot' configure-time option.
2079 * "info sharedlibrary" now takes an optional regex of libraries to show,
2080 and it now reports if a shared library has no debugging information.
2082 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2083 now complete on file names.
2085 * When completing in expressions, gdb will attempt to limit
2086 completions to allowable structure or union fields, where appropriate.
2087 For instance, consider:
2089 # struct example { int f1; double f2; };
2090 # struct example variable;
2093 If the user types TAB at the end of this command line, the available
2094 completions will be "f1" and "f2".
2096 * Inlined functions are now supported. They show up in backtraces, and
2097 the "step", "next", and "finish" commands handle them automatically.
2099 * GDB now supports the token-splicing (##) and stringification (#)
2100 operators when expanding macros. It also supports variable-arity
2103 * GDB now supports inspecting extra signal information, exported by
2104 the new $_siginfo convenience variable. The feature is currently
2105 implemented on linux ARM, i386 and amd64.
2107 * GDB can now display the VFP floating point registers and NEON vector
2108 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2109 can provide these registers (requires Linux 2.6.30 or later). Remote
2110 and simulator targets may also provide them.
2112 * New remote packets
2115 Search memory for a sequence of bytes.
2118 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2119 operation over reliable transport links. Use of this packet is
2120 controlled by the `set remote noack-packet' command.
2123 Kill the process with the specified process ID. Use this in preference
2124 to `k' when multiprocess protocol extensions are supported.
2127 Obtains additional operating system information
2131 Read or write additional signal information.
2133 * Removed remote protocol undocumented extension
2135 An undocumented extension to the remote protocol's `S' stop reply
2136 packet that permited the stub to pass a process id was removed.
2137 Remote servers should use the `T' stop reply packet instead.
2139 * GDB now supports multiple function calling conventions according to the
2140 DWARF-2 DW_AT_calling_convention function attribute.
2142 * The SH target utilizes the aforementioned change to distinguish between gcc
2143 and Renesas calling convention. It also adds the new CLI commands
2144 `set/show sh calling-convention'.
2146 * GDB can now read compressed debug sections, as produced by GNU gold
2147 with the --compress-debug-sections=zlib flag.
2149 * 64-bit core files are now supported on AIX.
2151 * Thread switching is now supported on Tru64.
2153 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2154 which will be allocated using malloc later in program execution.
2156 * The qXfer:libraries:read remote procotol packet now allows passing a
2157 list of section offsets.
2159 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2160 conditions handling signals delivered during attach or thread creation
2161 have also been fixed.
2163 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2164 From the user's standpoint, all unqualified instances of True and False
2165 are treated as the standard definitions, regardless of context.
2167 * GDB now parses C++ symbol and type names more flexibly. For
2170 template<typename T> class C { };
2173 GDB will now correctly handle all of:
2175 ptype C<char const *>
2176 ptype C<char const*>
2177 ptype C<const char *>
2178 ptype C<const char*>
2180 * New features in the GDB remote stub, gdbserver
2182 - The "--wrapper" command-line argument tells gdbserver to use a
2183 wrapper program to launch programs for debugging.
2185 - On PowerPC and S/390 targets, it is now possible to use a single
2186 gdbserver executable to debug both 32-bit and 64-bit programs.
2187 (This requires gdbserver itself to be built as a 64-bit executable.)
2189 - gdbserver uses the new noack protocol mode for TCP connections to
2190 reduce communications latency, if also supported and enabled in GDB.
2192 - Support for the sparc64-linux-gnu target is now included in
2195 - The amd64-linux build of gdbserver now supports debugging both
2196 32-bit and 64-bit programs.
2198 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2199 now support hardware watchpoints, and will use them automatically
2204 GDB now has support for scripting using Python. Whether this is
2205 available is determined at configure time.
2207 New GDB commands can now be written in Python.
2209 * Ada tasking support
2211 Ada tasks can now be inspected in GDB. The following commands have
2215 Print the list of Ada tasks.
2217 Print detailed information about task number N.
2219 Print the task number of the current task.
2221 Switch the context of debugging to task number N.
2223 * Support for user-defined prefixed commands. The "define" command can
2224 add new commands to existing prefixes, e.g. "target".
2226 * Multi-inferior, multi-process debugging.
2228 GDB now has generalized support for multi-inferior debugging. See
2229 "Debugging Multiple Inferiors" in the manual for more information.
2230 Although availability still depends on target support, the command
2231 set is more uniform now. The GNU/Linux specific multi-forks support
2232 has been migrated to this new framework. This implied some user
2233 visible changes; see "New commands" and also "Removed commands"
2236 * Target descriptions can now describe the target OS ABI. See the
2237 "Target Description Format" section in the user manual for more
2240 * Target descriptions can now describe "compatible" architectures
2241 to indicate that the target can execute applications for a different
2242 architecture in addition to those for the main target architecture.
2243 See the "Target Description Format" section in the user manual for
2246 * Multi-architecture debugging.
2248 GDB now includes general supports for debugging applications on
2249 hybrid systems that use more than one single processor architecture
2250 at the same time. Each such hybrid architecture still requires
2251 specific support to be added. The only hybrid architecture supported
2252 in this version of GDB is the Cell Broadband Engine.
2254 * GDB now supports integrated debugging of Cell/B.E. applications that
2255 use both the PPU and SPU architectures. To enable support for hybrid
2256 Cell/B.E. debugging, you need to configure GDB to support both the
2257 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2258 --enable-targets configure option.
2260 * Non-stop mode debugging.
2262 For some targets, GDB now supports an optional mode of operation in
2263 which you can examine stopped threads while other threads continue
2264 to execute freely. This is referred to as non-stop mode, with the
2265 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2266 section in the user manual for more information.
2268 To be able to support remote non-stop debugging, a remote stub needs
2269 to implement the non-stop mode remote protocol extensions, as
2270 described in the "Remote Non-Stop" section of the user manual. The
2271 GDB remote stub, gdbserver, has been adjusted to support these
2272 extensions on linux targets.
2274 * New commands (for set/show, see "New options" below)
2276 catch syscall [NAME(S) | NUMBER(S)]
2277 Catch system calls. Arguments, which should be names of system
2278 calls or their numbers, mean catch only those syscalls. Without
2279 arguments, every syscall will be caught. When the inferior issues
2280 any of the specified syscalls, GDB will stop and announce the system
2281 call, both when it is called and when its call returns. This
2282 feature is currently available with a native GDB running on the
2283 Linux Kernel, under the following architectures: x86, x86_64,
2284 PowerPC and PowerPC64.
2286 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2288 Search memory for a sequence of bytes.
2290 maint set python print-stack
2291 maint show python print-stack
2292 Show a stack trace when an error is encountered in a Python script.
2295 Invoke CODE by passing it to the Python interpreter.
2300 These allow macros to be defined, undefined, and listed
2304 Show operating system information about processes.
2307 List the inferiors currently under GDB's control.
2310 Switch focus to inferior number NUM.
2313 Detach from inferior number NUM.
2316 Kill inferior number NUM.
2320 set spu stop-on-load
2321 show spu stop-on-load
2322 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2324 set spu auto-flush-cache
2325 show spu auto-flush-cache
2326 Control whether to automatically flush the software-managed cache
2327 during Cell/B.E. debugging.
2329 set sh calling-convention
2330 show sh calling-convention
2331 Control the calling convention used when calling SH target functions.
2334 show debug timestamp
2335 Control display of timestamps with GDB debugging output.
2337 set disassemble-next-line
2338 show disassemble-next-line
2339 Control display of disassembled source lines or instructions when
2342 set remote noack-packet
2343 show remote noack-packet
2344 Set/show the use of remote protocol QStartNoAckMode packet. See above
2345 under "New remote packets."
2347 set remote query-attached-packet
2348 show remote query-attached-packet
2349 Control use of remote protocol `qAttached' (query-attached) packet.
2351 set remote read-siginfo-object
2352 show remote read-siginfo-object
2353 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2356 set remote write-siginfo-object
2357 show remote write-siginfo-object
2358 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2361 set remote reverse-continue
2362 show remote reverse-continue
2363 Control use of remote protocol 'bc' (reverse-continue) packet.
2365 set remote reverse-step
2366 show remote reverse-step
2367 Control use of remote protocol 'bs' (reverse-step) packet.
2369 set displaced-stepping
2370 show displaced-stepping
2371 Control displaced stepping mode. Displaced stepping is a way to
2372 single-step over breakpoints without removing them from the debuggee.
2373 Also known as "out-of-line single-stepping".
2376 show debug displaced
2377 Control display of debugging info for displaced stepping.
2379 maint set internal-error
2380 maint show internal-error
2381 Control what GDB does when an internal error is detected.
2383 maint set internal-warning
2384 maint show internal-warning
2385 Control what GDB does when an internal warning is detected.
2390 Use a wrapper program to launch programs for debugging.
2392 set multiple-symbols (all|ask|cancel)
2393 show multiple-symbols
2394 The value of this variable can be changed to adjust the debugger behavior
2395 when an expression or a breakpoint location contains an ambiguous symbol
2396 name (an overloaded function name, for instance).
2398 set breakpoint always-inserted
2399 show breakpoint always-inserted
2400 Keep breakpoints always inserted in the target, as opposed to inserting
2401 them when resuming the target, and removing them when the target stops.
2402 This option can improve debugger performance on slow remote targets.
2404 set arm fallback-mode (arm|thumb|auto)
2405 show arm fallback-mode
2406 set arm force-mode (arm|thumb|auto)
2408 These commands control how ARM GDB determines whether instructions
2409 are ARM or Thumb. The default for both settings is auto, which uses
2410 the current CPSR value for instructions without symbols; previous
2411 versions of GDB behaved as if "set arm fallback-mode arm".
2413 set disable-randomization
2414 show disable-randomization
2415 Standalone programs run with the virtual address space randomization enabled
2416 by default on some platforms. This option keeps the addresses stable across
2417 multiple debugging sessions.
2421 Control whether other threads are stopped or not when some thread hits
2426 Requests that asynchronous execution is enabled in the target, if available.
2427 In this case, it's possible to resume target in the background, and interact
2428 with GDB while the target is running. "show target-async" displays the
2429 current state of asynchronous execution of the target.
2431 set target-wide-charset
2432 show target-wide-charset
2433 The target-wide-charset is the name of the character set that GDB
2434 uses when printing characters whose type is wchar_t.
2436 set tcp auto-retry (on|off)
2438 set tcp connect-timeout
2439 show tcp connect-timeout
2440 These commands allow GDB to retry failed TCP connections to a remote stub
2441 with a specified timeout period; this is useful if the stub is launched
2442 in parallel with GDB but may not be ready to accept connections immediately.
2444 set libthread-db-search-path
2445 show libthread-db-search-path
2446 Control list of directories which GDB will search for appropriate
2449 set schedule-multiple (on|off)
2450 show schedule-multiple
2451 Allow GDB to resume all threads of all processes or only threads of
2452 the current process.
2456 Use more aggressive caching for accesses to the stack. This improves
2457 performance of remote debugging (particularly backtraces) without
2458 affecting correctness.
2460 set interactive-mode (on|off|auto)
2461 show interactive-mode
2462 Control whether GDB runs in interactive mode (on) or not (off).
2463 When in interactive mode, GDB waits for the user to answer all
2464 queries. Otherwise, GDB does not wait and assumes the default
2465 answer. When set to auto (the default), GDB determines which
2466 mode to use based on the stdin settings.
2471 For program forks, this is replaced by the new more generic `info
2472 inferiors' command. To list checkpoints, you can still use the
2473 `info checkpoints' command, which was an alias for the `info forks'
2477 Replaced by the new `inferior' command. To switch between
2478 checkpoints, you can still use the `restart' command, which was an
2479 alias for the `fork' command.
2482 This is removed, since some targets don't have a notion of
2483 processes. To switch between processes, you can still use the
2484 `inferior' command using GDB's own inferior number.
2487 For program forks, this is replaced by the new more generic `kill
2488 inferior' command. To delete a checkpoint, you can still use the
2489 `delete checkpoint' command, which was an alias for the `delete
2493 For program forks, this is replaced by the new more generic `detach
2494 inferior' command. To detach a checkpoint, you can still use the
2495 `detach checkpoint' command, which was an alias for the `detach
2498 * New native configurations
2500 x86/x86_64 Darwin i[34567]86-*-darwin*
2502 x86_64 MinGW x86_64-*-mingw*
2506 Lattice Mico32 lm32-*
2507 x86 DICOS i[34567]86-*-dicos*
2508 x86_64 DICOS x86_64-*-dicos*
2511 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2512 (mingw32ce) debugging.
2518 These commands were actually not implemented on any target.
2520 *** Changes in GDB 6.8
2522 * New native configurations
2524 NetBSD/hppa hppa*-*netbsd*
2525 Xtensa GNU/Linux xtensa*-*-linux*
2529 NetBSD/hppa hppa*-*-netbsd*
2530 Xtensa GNU/Lunux xtensa*-*-linux*
2532 * Change in command line behavior -- corefiles vs. process ids.
2534 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2535 attaching to process NUMBER fails, GDB no longer attempts to open a
2536 core file named NUMBER. Attaching to a program using the -c option
2537 is no longer supported. Instead, use the '-p' or '--pid' options.
2539 * GDB can now be built as a native debugger for debugging Windows x86
2540 (mingw32) Portable Executable (PE) programs.
2542 * Pending breakpoints no longer change their number when their address
2545 * GDB now supports breakpoints with multiple locations,
2546 including breakpoints on C++ constructors, inside C++ templates,
2547 and in inlined functions.
2549 * GDB's ability to debug optimized code has been improved. GDB more
2550 accurately identifies function bodies and lexical blocks that occupy
2551 more than one contiguous range of addresses.
2553 * Target descriptions can now describe registers for PowerPC.
2555 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2556 registers on PowerPC targets.
2558 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2559 targets even when the libthread_db library is not available.
2561 * The GDB remote stub, gdbserver, now supports the new file transfer
2562 commands (remote put, remote get, and remote delete).
2564 * The GDB remote stub, gdbserver, now supports run and attach in
2565 extended-remote mode.
2567 * hppa*64*-*-hpux11* target broken
2568 The debugger is unable to start a program and fails with the following
2569 error: "Error trying to get information about dynamic linker".
2570 The gdb-6.7 release is also affected.
2572 * GDB now supports the --enable-targets= configure option to allow
2573 building a single GDB executable that supports multiple remote
2574 target architectures.
2576 * GDB now supports debugging C and C++ programs which use the
2577 Decimal Floating Point extension. In addition, the PowerPC target
2578 now has a set of pseudo-registers to inspect decimal float values
2579 stored in two consecutive float registers.
2581 * The -break-insert MI command can optionally create pending
2584 * Improved support for debugging Ada
2585 Many improvements to the Ada language support have been made. These
2587 - Better support for Ada2005 interface types
2588 - Improved handling of arrays and slices in general
2589 - Better support for Taft-amendment types
2590 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2592 - Improved command completion in Ada
2595 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2600 set print frame-arguments (all|scalars|none)
2601 show print frame-arguments
2602 The value of this variable can be changed to control which argument
2603 values should be printed by the debugger when displaying a frame.
2608 Transfer files to and from a remote target, and delete remote files.
2615 Transfer files to and from a remote target, and delete remote files.
2617 * New remote packets
2624 Open, close, read, write, and delete files on the remote system.
2627 Attach to an existing process on the remote system, in extended-remote
2631 Run a new process on the remote system, in extended-remote mode.
2633 *** Changes in GDB 6.7
2635 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2636 bfd, libiberty and opcodes, as revealed by static analysis donated by
2637 Coverity, Inc. (http://scan.coverity.com).
2639 * When looking up multiply-defined global symbols, GDB will now prefer the
2640 symbol definition in the current shared library if it was built using the
2641 -Bsymbolic linker option.
2643 * When the Text User Interface (TUI) is not configured, GDB will now
2644 recognize the -tui command-line option and print a message that the TUI
2647 * The GDB remote stub, gdbserver, now has lower overhead for high
2648 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2650 * GDB for MIPS targets now autodetects whether a remote target provides
2651 32-bit or 64-bit register values.
2653 * Support for C++ member pointers has been improved.
2655 * GDB now understands XML target descriptions, which specify the
2656 target's overall architecture. GDB can read a description from
2657 a local file or over the remote serial protocol.
2659 * Vectors of single-byte data use a new integer type which is not
2660 automatically displayed as character or string data.
2662 * The /s format now works with the print command. It displays
2663 arrays of single-byte integers and pointers to single-byte integers
2666 * Target descriptions can now describe target-specific registers,
2667 for architectures which have implemented the support (currently
2668 only ARM, M68K, and MIPS).
2670 * GDB and the GDB remote stub, gdbserver, now support the XScale
2673 * The GDB remote stub, gdbserver, has been updated to support
2674 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2675 has been rewritten to use the standard GDB remote protocol.
2677 * GDB can now step into C++ functions which are called through thunks.
2679 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2681 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2682 layout. It also supports a TextSeg= and DataSeg= response when only
2683 segment base addresses (rather than offsets) are available.
2685 * The /i format now outputs any trailing branch delay slot instructions
2686 immediately following the last instruction within the count specified.
2688 * The GDB remote protocol "T" stop reply packet now supports a
2689 "library" response. Combined with the new "qXfer:libraries:read"
2690 packet, this response allows GDB to debug shared libraries on targets
2691 where the operating system manages the list of loaded libraries (e.g.
2692 Windows and SymbianOS).
2694 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2695 (DLLs) on Windows and Windows CE targets.
2697 * GDB now supports a faster verification that a .debug file matches its binary
2698 according to its build-id signature, if the signature is present.
2704 Enable or disable hardware flow control (RTS/CTS) on the serial port
2705 when debugging using remote targets.
2707 set mem inaccessible-by-default
2708 show mem inaccessible-by-default
2709 If the target supplies a memory map, for instance via the remote
2710 protocol's "qXfer:memory-map:read" packet, setting this variable
2711 prevents GDB from accessing memory outside the memory map. This
2712 is useful for targets with memory mapped registers or which react
2713 badly to accesses of unmapped address space.
2715 set breakpoint auto-hw
2716 show breakpoint auto-hw
2717 If the target supplies a memory map, for instance via the remote
2718 protocol's "qXfer:memory-map:read" packet, setting this variable
2719 lets GDB use hardware breakpoints automatically for memory regions
2720 where it can not use software breakpoints. This covers both the
2721 "break" command and internal breakpoints used for other commands
2722 including "next" and "finish".
2725 catch exception unhandled
2726 Stop the program execution when Ada exceptions are raised.
2729 Stop the program execution when an Ada assertion failed.
2733 Set an alternate system root for target files. This is a more
2734 general version of "set solib-absolute-prefix", which is now
2735 an alias to "set sysroot".
2738 Provide extended SPU facility status information. This set of
2739 commands is available only when debugging the Cell/B.E. SPU
2742 * New native configurations
2744 OpenBSD/sh sh*-*openbsd*
2747 unset tdesc filename
2749 Use the specified local file as an XML target description, and do
2750 not query the target for its built-in description.
2754 OpenBSD/sh sh*-*-openbsd*
2755 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2756 Toshiba Media Processor mep-elf
2758 * New remote packets
2761 Ignore the specified signals; pass them directly to the debugged program
2762 without stopping other threads or reporting them to GDB.
2764 qXfer:features:read:
2765 Read an XML target description from the target, which describes its
2770 Read or write contents of an spufs file on the target system. These
2771 packets are available only on the Cell/B.E. SPU architecture.
2773 qXfer:libraries:read:
2774 Report the loaded shared libraries. Combined with new "T" packet
2775 response, this packet allows GDB to debug shared libraries on
2776 targets where the operating system manages the list of loaded
2777 libraries (e.g. Windows and SymbianOS).
2781 Support for these obsolete configurations has been removed.
2789 i[34567]86-*-lynxos*
2790 i[34567]86-*-netware*
2791 i[34567]86-*-sco3.2v5*
2792 i[34567]86-*-sco3.2v4*
2794 i[34567]86-*-sysv4.2*
2797 i[34567]86-*-unixware2*
2798 i[34567]86-*-unixware*
2807 * Other removed features
2814 Various m68k-only ROM monitors.
2821 Various Renesas ROM monitors and debugging interfaces for SH and
2826 Support for a Macraigor serial interface to on-chip debugging.
2827 GDB does not directly support the newer parallel or USB
2832 A debug information format. The predecessor to DWARF 2 and
2833 DWARF 3, which are still supported.
2835 Support for the HP aCC compiler on HP-UX/PA-RISC
2837 SOM-encapsulated symbolic debugging information, automatic
2838 invocation of pxdb, and the aCC custom C++ ABI. This does not
2839 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2840 with aCC can still be debugged on an assembly level.
2842 MIPS ".pdr" sections
2844 A MIPS-specific format used to describe stack frame layout
2845 in debugging information.
2849 GDB could work with an older version of Guile to debug
2850 the interpreter and Scheme programs running in it.
2852 set mips stack-arg-size
2853 set mips saved-gpreg-size
2855 Use "set mips abi" to control parameter passing for MIPS.
2857 *** Changes in GDB 6.6
2862 Cell Broadband Engine SPU spu-elf
2864 * GDB can now be configured as a cross-debugger targeting native Windows
2865 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2866 running on a Windows system over TCP/IP to debug Windows programs.
2868 * The GDB remote stub, gdbserver, has been updated to support Windows and
2869 Cygwin debugging. Both single-threaded and multi-threaded programs are
2872 * The "set trust-readonly-sections" command works again. This command was
2873 broken in GDB 6.3, 6.4, and 6.5.
2875 * The "load" command now supports writing to flash memory, if the remote
2876 stub provides the required support.
2878 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2879 longer requires symbolic debug information (e.g. DWARF-2).
2884 unset substitute-path
2885 show substitute-path
2886 Manage a list of substitution rules that GDB uses to rewrite the name
2887 of the directories where the sources are located. This can be useful
2888 for instance when the sources were moved to a different location
2889 between compilation and debugging.
2893 Print each CLI command as it is executed. Each command is prefixed with
2894 a number of `+' symbols representing the nesting depth.
2895 The source command now has a `-v' option to enable the same feature.
2899 The ARM Demon monitor support (RDP protocol, "target rdp").
2901 Kernel Object Display, an embedded debugging feature which only worked with
2902 an obsolete version of Cisco IOS.
2904 The 'set download-write-size' and 'show download-write-size' commands.
2906 * New remote packets
2909 Tell a stub about GDB client features, and request remote target features.
2910 The first feature implemented is PacketSize, which allows the target to
2911 specify the size of packets it can handle - to minimize the number of
2912 packets required and improve performance when connected to a remote
2916 Fetch an OS auxilliary vector from the remote stub. This packet is a
2917 more efficient replacement for qPart:auxv:read.
2919 qXfer:memory-map:read:
2920 Fetch a memory map from the remote stub, including information about
2921 RAM, ROM, and flash memory devices.
2926 Erase and program a flash memory device.
2928 * Removed remote packets
2931 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2932 used it, and only gdbserver implemented it.
2934 *** Changes in GDB 6.5
2938 Renesas M32C/M16C m32c-elf
2940 Morpho Technologies ms1 ms1-elf
2944 init-if-undefined Initialize a convenience variable, but
2945 only if it doesn't already have a value.
2947 The following commands are presently only implemented for native GNU/Linux:
2949 checkpoint Save a snapshot of the program state.
2951 restart <n> Return the program state to a
2952 previously saved state.
2954 info checkpoints List currently saved checkpoints.
2956 delete-checkpoint <n> Delete a previously saved checkpoint.
2958 set|show detach-on-fork Tell gdb whether to detach from a newly
2959 forked process, or to keep debugging it.
2961 info forks List forks of the user program that
2962 are available to be debugged.
2964 fork <n> Switch to debugging one of several
2965 forks of the user program that are
2966 available to be debugged.
2968 delete-fork <n> Delete a fork from the list of forks
2969 that are available to be debugged (and
2970 kill the forked process).
2972 detach-fork <n> Delete a fork from the list of forks
2973 that are available to be debugged (and
2974 allow the process to continue).
2978 Morpho Technologies ms2 ms1-elf
2980 * Improved Windows host support
2982 GDB now builds as a cross debugger hosted on i686-mingw32, including
2983 native console support, and remote communications using either
2984 network sockets or serial ports.
2986 * Improved Modula-2 language support
2988 GDB can now print most types in the Modula-2 syntax. This includes:
2989 basic types, set types, record types, enumerated types, range types,
2990 pointer types and ARRAY types. Procedure var parameters are correctly
2991 printed and hexadecimal addresses and character constants are also
2992 written in the Modula-2 syntax. Best results can be obtained by using
2993 GNU Modula-2 together with the -gdwarf-2 command line option.
2997 The ARM rdi-share module.
2999 The Netware NLM debug server.
3001 *** Changes in GDB 6.4
3003 * New native configurations
3005 OpenBSD/arm arm*-*-openbsd*
3006 OpenBSD/mips64 mips64-*-openbsd*
3010 Morpho Technologies ms1 ms1-elf
3012 * New command line options
3014 --batch-silent As for --batch, but totally silent.
3015 --return-child-result The debugger will exist with the same value
3016 the child (debugged) program exited with.
3017 --eval-command COMMAND, -ex COMMAND
3018 Execute a single GDB CLI command. This may be
3019 specified multiple times and in conjunction
3020 with the --command (-x) option.
3022 * Deprecated commands removed
3024 The following commands, that were deprecated in 2000, have been
3028 set|show arm disassembly-flavor set|show arm disassembler
3029 othernames set arm disassembler
3030 set|show remotedebug set|show debug remote
3031 set|show archdebug set|show debug arch
3032 set|show eventdebug set|show debug event
3035 * New BSD user-level threads support
3037 It is now possible to debug programs using the user-level threads
3038 library on OpenBSD and FreeBSD. Currently supported (target)
3041 FreeBSD/amd64 x86_64-*-freebsd*
3042 FreeBSD/i386 i386-*-freebsd*
3043 OpenBSD/i386 i386-*-openbsd*
3045 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3046 are not yet supported.
3048 * New support for Matsushita MN10300 w/sim added
3049 (Work in progress). mn10300-elf.
3051 * REMOVED configurations and files
3053 VxWorks and the XDR protocol *-*-vxworks
3054 Motorola MCORE mcore-*-*
3055 National Semiconductor NS32000 ns32k-*-*
3057 * New "set print array-indexes" command
3059 After turning this setting "on", GDB prints the index of each element
3060 when displaying arrays. The default is "off" to preserve the previous
3063 * VAX floating point support
3065 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3067 * User-defined command support
3069 In addition to using $arg0..$arg9 for argument passing, it is now possible
3070 to use $argc to determine now many arguments have been passed. See the
3071 section on user-defined commands in the user manual for more information.
3073 *** Changes in GDB 6.3:
3075 * New command line option
3077 GDB now accepts -l followed by a number to set the timeout for remote
3080 * GDB works with GCC -feliminate-dwarf2-dups
3082 GDB now supports a more compact representation of DWARF-2 debug
3083 information using DW_FORM_ref_addr references. These are produced
3084 by GCC with the option -feliminate-dwarf2-dups and also by some
3085 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3086 to use -feliminate-dwarf2-dups.
3088 * Internationalization
3090 When supported by the host system, GDB will be built with
3091 internationalization (libintl). The task of marking up the sources is
3092 continued, we're looking forward to our first translation.
3096 Initial support for debugging programs compiled with the GNAT
3097 implementation of the Ada programming language has been integrated
3098 into GDB. In this release, support is limited to expression evaluation.
3100 * New native configurations
3102 GNU/Linux/m32r m32r-*-linux-gnu
3106 GDB's remote protocol now includes support for the 'p' packet. This
3107 packet is used to fetch individual registers from a remote inferior.
3109 * END-OF-LIFE registers[] compatibility module
3111 GDB's internal register infrastructure has been completely rewritten.
3112 The new infrastructure making possible the implementation of key new
3113 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3116 GDB 6.3 will be the last release to include the the registers[]
3117 compatibility module that allowed out-of-date configurations to
3118 continue to work. This change directly impacts the following
3128 powerpc bdm protocol
3130 Unless there is activity to revive these configurations, they will be
3131 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3133 * OBSOLETE configurations and files
3135 Configurations that have been declared obsolete in this release have
3136 been commented out. Unless there is activity to revive these
3137 configurations, the next release of GDB will have their sources
3138 permanently REMOVED.
3147 *** Changes in GDB 6.2.1:
3149 * MIPS `break main; run' gave an heuristic-fence-post warning
3151 When attempting to run even a simple program, a warning about
3152 heuristic-fence-post being hit would be reported. This problem has
3155 * MIPS IRIX 'long double' crashed GDB
3157 When examining a long double variable, GDB would get a segmentation
3158 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3159 IRIX long double values).
3163 A bug in the VAX stack code was causing problems with the "next"
3164 command. This problem has been fixed.
3166 *** Changes in GDB 6.2:
3168 * Fix for ``many threads''
3170 On GNU/Linux systems that use the NPTL threads library, a program
3171 rapidly creating and deleting threads would confuse GDB leading to the
3174 ptrace: No such process.
3175 thread_db_get_info: cannot get thread info: generic error
3177 This problem has been fixed.
3179 * "-async" and "-noasync" options removed.
3181 Support for the broken "-noasync" option has been removed (it caused
3184 * New ``start'' command.
3186 This command runs the program until the begining of the main procedure.
3188 * New BSD Kernel Data Access Library (libkvm) interface
3190 Using ``target kvm'' it is now possible to debug kernel core dumps and
3191 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3192 platforms. Currently supported (native-only) configurations are:
3194 FreeBSD/amd64 x86_64-*-freebsd*
3195 FreeBSD/i386 i?86-*-freebsd*
3196 NetBSD/i386 i?86-*-netbsd*
3197 NetBSD/m68k m68*-*-netbsd*
3198 NetBSD/sparc sparc-*-netbsd*
3199 OpenBSD/amd64 x86_64-*-openbsd*
3200 OpenBSD/i386 i?86-*-openbsd*
3201 OpenBSD/m68k m68*-openbsd*
3202 OpenBSD/sparc sparc-*-openbsd*
3204 * Signal trampoline code overhauled
3206 Many generic problems with GDB's signal handling code have been fixed.
3207 These include: backtraces through non-contiguous stacks; recognition
3208 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3209 call; backtrace through a signal trampoline; step into and out of
3210 signal handlers; and single-stepping in the signal trampoline.
3212 Please note that kernel bugs are a limiting factor here. These
3213 features have been shown to work on an s390 GNU/Linux system that
3214 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3216 * Cygwin support for DWARF 2 added.
3218 * New native configurations
3220 GNU/Linux/hppa hppa*-*-linux*
3221 OpenBSD/hppa hppa*-*-openbsd*
3222 OpenBSD/m68k m68*-*-openbsd*
3223 OpenBSD/m88k m88*-*-openbsd*
3224 OpenBSD/powerpc powerpc-*-openbsd*
3225 NetBSD/vax vax-*-netbsd*
3226 OpenBSD/vax vax-*-openbsd*
3228 * END-OF-LIFE frame compatibility module
3230 GDB's internal frame infrastructure has been completely rewritten.
3231 The new infrastructure making it possible to support key new features
3232 including DWARF 2 Call Frame Information. To aid in the task of
3233 migrating old configurations to this new infrastructure, a
3234 compatibility module, that allowed old configurations to continue to
3235 work, was also included.
3237 GDB 6.2 will be the last release to include this frame compatibility
3238 module. This change directly impacts the following configurations:
3248 Unless there is activity to revive these configurations, they will be
3249 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3251 * REMOVED configurations and files
3253 Sun 3, running SunOS 3 m68*-*-sunos3*
3254 Sun 3, running SunOS 4 m68*-*-sunos4*
3255 Sun 2, running SunOS 3 m68000-*-sunos3*
3256 Sun 2, running SunOS 4 m68000-*-sunos4*
3257 Motorola 680x0 running LynxOS m68*-*-lynxos*
3258 AT&T 3b1/Unix pc m68*-att-*
3259 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3260 decstation mips-dec-* mips-little-*
3261 riscos mips-*-riscos* mips-*-sysv*
3262 sonymips mips-sony-*
3263 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3265 *** Changes in GDB 6.1.1:
3267 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3269 The TUI (Text-mode User Interface) is now built as part of a default
3270 GDB configuration. It is enabled by either selecting the TUI with the
3271 command line option "-i=tui" or by running the separate "gdbtui"
3272 program. For more information on the TUI, see the manual "Debugging
3275 * Pending breakpoint support (also included in GDB 6.1)
3277 Support has been added to allow you to specify breakpoints in shared
3278 libraries that have not yet been loaded. If a breakpoint location
3279 cannot be found, and the "breakpoint pending" option is set to auto,
3280 GDB queries you if you wish to make the breakpoint pending on a future
3281 shared-library load. If and when GDB resolves the breakpoint symbol,
3282 the pending breakpoint is removed as one or more regular breakpoints
3285 Pending breakpoints are very useful for GCJ Java debugging.
3287 * Fixed ISO-C build problems
3289 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3290 non ISO-C code that stopped them being built using a more strict ISO-C
3291 compiler (e.g., IBM's C compiler).
3293 * Fixed build problem on IRIX 5
3295 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3296 wasn't able to compile compile on an IRIX 5 system.
3298 * Added execute permission to gdb/gdbserver/configure
3300 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3301 permission. This bug would cause configure to fail on a number of
3302 systems (Solaris, IRIX). Ref: server/519.
3304 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3306 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3307 has been updated to use constant array sizes.
3309 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3311 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3312 its generated DWARF Call Frame Info. This encoding was causing GDB to
3313 panic, that panic has been fixed. Ref: gdb/1628.
3315 * Fixed a problem when examining parameters in shared library code.
3317 When examining parameters in optimized shared library code generated
3318 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3319 not available''. GDB now correctly displays the variable's value.
3321 *** Changes in GDB 6.1:
3323 * Removed --with-mmalloc
3325 Support for the mmalloc memory manager has been removed, as it
3326 conflicted with the internal gdb byte cache.
3328 * Changes in AMD64 configurations
3330 The AMD64 target now includes the %cs and %ss registers. As a result
3331 the AMD64 remote protocol has changed; this affects the floating-point
3332 and SSE registers. If you rely on those registers for your debugging,
3333 you should upgrade gdbserver on the remote side.
3335 * Revised SPARC target
3337 The SPARC target has been completely revised, incorporating the
3338 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3339 support for LynxOS and SunOS 4 has been dropped. Calling functions
3340 from within GDB on operating systems with a non-executable stack
3341 (Solaris, OpenBSD) now works.
3345 GDB has a new C++ demangler which does a better job on the mangled
3346 names generated by current versions of g++. It also runs faster, so
3347 with this and other changes gdb should now start faster on large C++
3350 * DWARF 2 Location Expressions
3352 GDB support for location expressions has been extended to support function
3353 arguments and frame bases. Older versions of GDB could crash when they
3356 * C++ nested types and namespaces
3358 GDB's support for nested types and namespaces in C++ has been
3359 improved, especially if you use the DWARF 2 debugging format. (This
3360 is the default for recent versions of GCC on most platforms.)
3361 Specifically, if you have a class "Inner" defined within a class or
3362 namespace "Outer", then GDB realizes that the class's name is
3363 "Outer::Inner", not simply "Inner". This should greatly reduce the
3364 frequency of complaints about not finding RTTI symbols. In addition,
3365 if you are stopped at inside of a function defined within a namespace,
3366 GDB modifies its name lookup accordingly.
3368 * New native configurations
3370 NetBSD/amd64 x86_64-*-netbsd*
3371 OpenBSD/amd64 x86_64-*-openbsd*
3372 OpenBSD/alpha alpha*-*-openbsd*
3373 OpenBSD/sparc sparc-*-openbsd*
3374 OpenBSD/sparc64 sparc64-*-openbsd*
3376 * New debugging protocols
3378 M32R with SDI protocol m32r-*-elf*
3380 * "set prompt-escape-char" command deleted.
3382 The command "set prompt-escape-char" has been deleted. This command,
3383 and its very obscure effet on GDB's prompt, was never documented,
3384 tested, nor mentioned in the NEWS file.
3386 * OBSOLETE configurations and files
3388 Configurations that have been declared obsolete in this release have
3389 been commented out. Unless there is activity to revive these
3390 configurations, the next release of GDB will have their sources
3391 permanently REMOVED.
3393 Sun 3, running SunOS 3 m68*-*-sunos3*
3394 Sun 3, running SunOS 4 m68*-*-sunos4*
3395 Sun 2, running SunOS 3 m68000-*-sunos3*
3396 Sun 2, running SunOS 4 m68000-*-sunos4*
3397 Motorola 680x0 running LynxOS m68*-*-lynxos*
3398 AT&T 3b1/Unix pc m68*-att-*
3399 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3400 decstation mips-dec-* mips-little-*
3401 riscos mips-*-riscos* mips-*-sysv*
3402 sonymips mips-sony-*
3403 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3405 * REMOVED configurations and files
3407 SGI Irix-4.x mips-sgi-irix4 or iris4
3408 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3409 Z8000 simulator z8k-zilog-none or z8ksim
3410 Matsushita MN10200 w/simulator mn10200-*-*
3411 H8/500 simulator h8500-hitachi-hms or h8500hms
3412 HP/PA running BSD hppa*-*-bsd*
3413 HP/PA running OSF/1 hppa*-*-osf*
3414 HP/PA Pro target hppa*-*-pro*
3415 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3416 386BSD i[3456]86-*-bsd*
3417 Sequent family i[3456]86-sequent-sysv4*
3418 i[3456]86-sequent-sysv*
3419 i[3456]86-sequent-bsd*
3420 SPARC running LynxOS sparc-*-lynxos*
3421 SPARC running SunOS 4 sparc-*-sunos4*
3422 Tsqware Sparclet sparclet-*-*
3423 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3425 *** Changes in GDB 6.0:
3429 Support for debugging the Objective-C programming language has been
3430 integrated into GDB.
3432 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3434 DWARF 2's Call Frame Information makes available compiler generated
3435 information that more exactly describes the program's run-time stack.
3436 By using this information, GDB is able to provide more robust stack
3439 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3440 have been updated to use a new backtrace mechanism which includes
3441 DWARF 2 CFI support.
3445 GDB's remote protocol has been extended to include support for hosted
3446 file I/O (where the remote target uses GDB's file system). See GDB's
3447 remote protocol documentation for details.
3449 * All targets using the new architecture framework.
3451 All of GDB's targets have been updated to use the new internal
3452 architecture framework. The way is now open for future GDB releases
3453 to include cross-architecture native debugging support (i386 on amd64,
3456 * GNU/Linux's Thread Local Storage (TLS)
3458 GDB now includes support for for the GNU/Linux implementation of
3459 per-thread variables.
3461 * GNU/Linux's Native POSIX Thread Library (NPTL)
3463 GDB's thread code has been updated to work with either the new
3464 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3466 * Separate debug info.
3468 GDB, in conjunction with BINUTILS, now supports a mechanism for
3469 automatically loading debug information from a separate file. Instead
3470 of shipping full debug and non-debug versions of system libraries,
3471 system integrators can now instead ship just the stripped libraries
3472 and optional debug files.
3474 * DWARF 2 Location Expressions
3476 DWARF 2 Location Expressions allow the compiler to more completely
3477 describe the location of variables (even in optimized code) to the
3480 GDB now includes preliminary support for location expressions (support
3481 for DW_OP_piece is still missing).
3485 A number of long standing bugs that caused GDB to die while starting a
3486 Java application have been fixed. GDB's Java support is now
3487 considered "useable".
3489 * GNU/Linux support for fork, vfork, and exec.
3491 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3492 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3495 * GDB supports logging output to a file
3497 There are two new commands, "set logging" and "show logging", which can be
3498 used to capture GDB's output to a file.
3500 * The meaning of "detach" has changed for gdbserver
3502 The "detach" command will now resume the application, as documented. To
3503 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3506 * d10v, m68hc11 `regs' command deprecated
3508 The `info registers' command has been updated so that it displays the
3509 registers using a format identical to the old `regs' command.
3513 A new command, "maint set profile on/off", has been added. This command can
3514 be used to enable or disable profiling while running GDB, to profile a
3515 session or a set of commands. In addition there is a new configure switch,
3516 "--enable-profiling", which will cause GDB to be compiled with profiling
3517 data, for more informative profiling results.
3519 * Default MI syntax changed to "mi2".
3521 The default MI (machine interface) syntax, enabled by the command line
3522 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3523 "mi1", can be enabled by specifying the option "-i=mi1".
3525 Support for the original "mi0" syntax (included in GDB 5.0) has been
3528 Fix for gdb/192: removed extraneous space when displaying frame level.
3529 Fix for gdb/672: update changelist is now output in mi list format.
3530 Fix for gdb/702: a -var-assign that updates the value now shows up
3531 in a subsequent -var-update.
3533 * New native configurations.
3535 FreeBSD/amd64 x86_64-*-freebsd*
3537 * Multi-arched targets.
3539 HP/PA HPUX11 hppa*-*-hpux*
3540 Renesas M32R/D w/simulator m32r-*-elf*
3542 * OBSOLETE configurations and files
3544 Configurations that have been declared obsolete in this release have
3545 been commented out. Unless there is activity to revive these
3546 configurations, the next release of GDB will have their sources
3547 permanently REMOVED.
3549 Z8000 simulator z8k-zilog-none or z8ksim
3550 Matsushita MN10200 w/simulator mn10200-*-*
3551 H8/500 simulator h8500-hitachi-hms or h8500hms
3552 HP/PA running BSD hppa*-*-bsd*
3553 HP/PA running OSF/1 hppa*-*-osf*
3554 HP/PA Pro target hppa*-*-pro*
3555 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3556 Sequent family i[3456]86-sequent-sysv4*
3557 i[3456]86-sequent-sysv*
3558 i[3456]86-sequent-bsd*
3559 Tsqware Sparclet sparclet-*-*
3560 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3562 * REMOVED configurations and files
3565 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3566 IBM AIX PS/2 i[3456]86-*-aix
3567 i386 running Mach 3.0 i[3456]86-*-mach3*
3568 i386 running Mach i[3456]86-*-mach*
3569 i386 running OSF/1 i[3456]86-*osf1mk*
3570 HP/Apollo 68k Family m68*-apollo*-sysv*,
3572 m68*-hp-bsd*, m68*-hp-hpux*
3573 Argonaut Risc Chip (ARC) arc-*-*
3574 Mitsubishi D30V d30v-*-*
3575 Fujitsu FR30 fr30-*-elf*
3576 OS/9000 i[34]86-*-os9k
3577 I960 with MON960 i960-*-coff
3579 * MIPS $fp behavior changed
3581 The convenience variable $fp, for the MIPS, now consistently returns
3582 the address of the current frame's base. Previously, depending on the
3583 context, $fp could refer to either $sp or the current frame's base
3584 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3585 The GNU Source-Level Debugger''.
3587 *** Changes in GDB 5.3:
3589 * GNU/Linux shared library multi-threaded performance improved.
3591 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3592 `/proc', in preference to `ptrace' for memory reads. This may result
3593 in an improvement in the start-up time of multi-threaded, shared
3594 library applications when run under GDB. One GDB user writes: ``loads
3595 shared libs like mad''.
3597 * ``gdbserver'' now supports multi-threaded applications on some targets
3599 Support for debugging multi-threaded applications which use
3600 the GNU/Linux LinuxThreads package has been added for
3601 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3602 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3604 * GDB now supports C/C++ preprocessor macros.
3606 GDB now expands preprocessor macro invocations in C/C++ expressions,
3607 and provides various commands for showing macro definitions and how
3610 The new command `macro expand EXPRESSION' expands any macro
3611 invocations in expression, and shows the result.
3613 The new command `show macro MACRO-NAME' shows the definition of the
3614 macro named MACRO-NAME, and where it was defined.
3616 Most compilers don't include information about macros in the debugging
3617 information by default. In GCC 3.1, for example, you need to compile
3618 your program with the options `-gdwarf-2 -g3'. If the macro
3619 information is present in the executable, GDB will read it.
3621 * Multi-arched targets.
3623 DEC Alpha (partial) alpha*-*-*
3624 DEC VAX (partial) vax-*-*
3626 National Semiconductor NS32000 (partial) ns32k-*-*
3627 Motorola 68000 (partial) m68k-*-*
3628 Motorola MCORE mcore-*-*
3632 Fujitsu FRV architecture added by Red Hat frv*-*-*
3635 * New native configurations
3637 Alpha NetBSD alpha*-*-netbsd*
3638 SH NetBSD sh*-*-netbsdelf*
3639 MIPS NetBSD mips*-*-netbsd*
3640 UltraSPARC NetBSD sparc64-*-netbsd*
3642 * OBSOLETE configurations and files
3644 Configurations that have been declared obsolete in this release have
3645 been commented out. Unless there is activity to revive these
3646 configurations, the next release of GDB will have their sources
3647 permanently REMOVED.
3649 Mitsubishi D30V d30v-*-*
3650 OS/9000 i[34]86-*-os9k
3651 IBM AIX PS/2 i[3456]86-*-aix
3652 Fujitsu FR30 fr30-*-elf*
3653 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3654 Argonaut Risc Chip (ARC) arc-*-*
3655 i386 running Mach 3.0 i[3456]86-*-mach3*
3656 i386 running Mach i[3456]86-*-mach*
3657 i386 running OSF/1 i[3456]86-*osf1mk*
3658 HP/Apollo 68k Family m68*-apollo*-sysv*,
3660 m68*-hp-bsd*, m68*-hp-hpux*
3661 I960 with MON960 i960-*-coff
3663 * OBSOLETE languages
3665 CHILL, a Pascal like language used by telecommunications companies.
3667 * REMOVED configurations and files
3669 AMD 29k family via UDI a29k-amd-udi, udi29k
3670 A29K VxWorks a29k-*-vxworks
3671 AMD 29000 embedded, using EBMON a29k-none-none
3672 AMD 29000 embedded with COFF a29k-none-coff
3673 AMD 29000 embedded with a.out a29k-none-aout
3675 testsuite/gdb.hp/gdb.threads-hp/ directory
3677 * New command "set max-user-call-depth <nnn>"
3679 This command allows the user to limit the call depth of user-defined
3680 commands. The default is 1024.
3682 * Changes in FreeBSD/i386 native debugging.
3684 Support for the "generate-core-file" has been added.
3686 * New commands "dump", "append", and "restore".
3688 These commands allow data to be copied from target memory
3689 to a bfd-format or binary file (dump and append), and back
3690 from a file into memory (restore).
3692 * Improved "next/step" support on multi-processor Alpha Tru64.
3694 The previous single-step mechanism could cause unpredictable problems,
3695 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3696 of a software single-step mechanism prevents this.
3698 *** Changes in GDB 5.2.1:
3706 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3707 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3708 Fix, by Joel Brobecker imported from mainline.
3710 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3711 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3712 Fix, by Fred Fish, imported from mainline.
3714 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3715 Surprisingly enough, it works now.
3716 By Michal Ludvig, imported from mainline.
3718 i386 hardware watchpoint support:
3719 avoid misses on second run for some targets.
3720 By Pierre Muller, imported from mainline.
3722 *** Changes in GDB 5.2:
3724 * New command "set trust-readonly-sections on[off]".
3726 This command is a hint that tells gdb that read-only sections
3727 really are read-only (ie. that their contents will not change).
3728 In this mode, gdb will go to the object file rather than the
3729 target to read memory from read-only sections (such as ".text").
3730 This can be a significant performance improvement on some
3731 (notably embedded) targets.
3733 * New command "generate-core-file" (or "gcore").
3735 This new gdb command allows the user to drop a core file of the child
3736 process state at any time. So far it's been implemented only for
3737 GNU/Linux and Solaris, but should be relatively easily ported to other
3738 hosts. Argument is core file name (defaults to core.<pid>).
3740 * New command line option
3742 GDB now accepts --pid or -p followed by a process id.
3744 * Change in command line behavior -- corefiles vs. process ids.
3746 There is a subtle behavior in the way in which GDB handles
3747 command line arguments. The first non-flag argument is always
3748 a program to debug, but the second non-flag argument may either
3749 be a corefile or a process id. Previously, GDB would attempt to
3750 open the second argument as a corefile, and if that failed, would
3751 issue a superfluous error message and then attempt to attach it as
3752 a process. Now, if the second argument begins with a non-digit,
3753 it will be treated as a corefile. If it begins with a digit,
3754 GDB will attempt to attach it as a process, and if no such process
3755 is found, will then attempt to open it as a corefile.
3757 * Changes in ARM configurations.
3759 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3760 configuration is fully multi-arch.
3762 * New native configurations
3764 ARM NetBSD arm*-*-netbsd*
3765 x86 OpenBSD i[3456]86-*-openbsd*
3766 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3767 Sparc64 running FreeBSD sparc64-*-freebsd*
3771 Sanyo XStormy16 xstormy16-elf
3773 * OBSOLETE configurations and files
3775 Configurations that have been declared obsolete in this release have
3776 been commented out. Unless there is activity to revive these
3777 configurations, the next release of GDB will have their sources
3778 permanently REMOVED.
3780 AMD 29k family via UDI a29k-amd-udi, udi29k
3781 A29K VxWorks a29k-*-vxworks
3782 AMD 29000 embedded, using EBMON a29k-none-none
3783 AMD 29000 embedded with COFF a29k-none-coff
3784 AMD 29000 embedded with a.out a29k-none-aout
3786 testsuite/gdb.hp/gdb.threads-hp/ directory
3788 * REMOVED configurations and files
3790 TI TMS320C80 tic80-*-*
3792 PowerPC Solaris powerpcle-*-solaris*
3793 PowerPC Windows NT powerpcle-*-cygwin32
3794 PowerPC Netware powerpc-*-netware*
3795 Harris/CXUX m88k m88*-harris-cxux*
3796 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3797 ns32k-utek-sysv* ns32k-utek-*
3798 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3799 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3800 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3801 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3802 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3804 * Changes to command line processing
3806 The new `--args' feature can be used to specify command-line arguments
3807 for the inferior from gdb's command line.
3809 * Changes to key bindings
3811 There is a new `operate-and-get-next' function bound to `C-o'.
3813 *** Changes in GDB 5.1.1
3815 Fix compile problem on DJGPP.
3817 Fix a problem with floating-point registers on the i386 being
3820 Fix to stop GDB crashing on .debug_str debug info.
3822 Numerous documentation fixes.
3824 Numerous testsuite fixes.
3826 *** Changes in GDB 5.1:
3828 * New native configurations
3830 Alpha FreeBSD alpha*-*-freebsd*
3831 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3832 MIPS GNU/Linux mips*-*-linux*
3833 MIPS SGI Irix 6.x mips*-sgi-irix6*
3834 ia64 AIX ia64-*-aix*
3835 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3839 Motorola 68HC11 and 68HC12 m68hc11-elf
3841 UltraSparc running GNU/Linux sparc64-*-linux*
3843 * OBSOLETE configurations and files
3845 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3846 Harris/CXUX m88k m88*-harris-cxux*
3847 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3848 ns32k-utek-sysv* ns32k-utek-*
3849 TI TMS320C80 tic80-*-*
3851 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3852 PowerPC Solaris powerpcle-*-solaris*
3853 PowerPC Windows NT powerpcle-*-cygwin32
3854 PowerPC Netware powerpc-*-netware*
3855 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3856 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3857 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3858 Apple Macintosh (MPW) host N/A
3860 stuff.c (Program to stuff files into a specially prepared space in kdb)
3861 kdb-start.c (Main loop for the standalone kernel debugger)
3863 Configurations that have been declared obsolete in this release have
3864 been commented out. Unless there is activity to revive these
3865 configurations, the next release of GDB will have their sources
3866 permanently REMOVED.
3868 * REMOVED configurations and files
3870 Altos 3068 m68*-altos-*
3871 Convex c1-*-*, c2-*-*
3873 ARM RISCix arm-*-* (as host)
3877 * GDB has been converted to ISO C.
3879 GDB's source code has been converted to ISO C. In particular, the
3880 sources are fully protoized, and rely on standard headers being
3885 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3887 * The MI enabled by default.
3889 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3890 revised and enabled by default. Packages which use GDB as a debugging
3891 engine behind a UI or another front end are encouraged to switch to
3892 using the GDB/MI interface, instead of the old annotations interface
3893 which is now deprecated.
3895 * Support for debugging Pascal programs.
3897 GDB now includes support for debugging Pascal programs. The following
3898 main features are supported:
3900 - Pascal-specific data types such as sets;
3902 - automatic recognition of Pascal sources based on file-name
3905 - Pascal-style display of data types, variables, and functions;
3907 - a Pascal expression parser.
3909 However, some important features are not yet supported.
3911 - Pascal string operations are not supported at all;
3913 - there are some problems with boolean types;
3915 - Pascal type hexadecimal constants are not supported
3916 because they conflict with the internal variables format;
3918 - support for Pascal objects and classes is not full yet;
3920 - unlike Pascal, GDB is case-sensitive for symbol names.
3922 * Changes in completion.
3924 Commands such as `shell', `run' and `set args', which pass arguments
3925 to inferior programs, now complete on file names, similar to what
3926 users expect at the shell prompt.
3928 Commands which accept locations, such as `disassemble', `print',
3929 `breakpoint', `until', etc. now complete on filenames as well as
3930 program symbols. Thus, if you type "break foob TAB", and the source
3931 files linked into the programs include `foobar.c', that file name will
3932 be one of the candidates for completion. However, file names are not
3933 considered for completion after you typed a colon that delimits a file
3934 name from a name of a function in that file, as in "break foo.c:bar".
3936 `set demangle-style' completes on available demangling styles.
3938 * New platform-independent commands:
3940 It is now possible to define a post-hook for a command as well as a
3941 hook that runs before the command. For more details, see the
3942 documentation of `hookpost' in the GDB manual.
3944 * Changes in GNU/Linux native debugging.
3946 Support for debugging multi-threaded programs has been completely
3947 revised for all platforms except m68k and sparc. You can now debug as
3948 many threads as your system allows you to have.
3950 Attach/detach is supported for multi-threaded programs.
3952 Support for SSE registers was added for x86. This doesn't work for
3953 multi-threaded programs though.
3955 * Changes in MIPS configurations.
3957 Multi-arch support is enabled for all MIPS configurations.
3959 GDB can now be built as native debugger on SGI Irix 6.x systems for
3960 debugging n32 executables. (Debugging 64-bit executables is not yet
3963 * Unified support for hardware watchpoints in all x86 configurations.
3965 Most (if not all) native x86 configurations support hardware-assisted
3966 breakpoints and watchpoints in a unified manner. This support
3967 implements debug register sharing between watchpoints, which allows to
3968 put a virtually infinite number of watchpoints on the same address,
3969 and also supports watching regions up to 16 bytes with several debug
3972 The new maintenance command `maintenance show-debug-regs' toggles
3973 debugging print-outs in functions that insert, remove, and test
3974 watchpoints and hardware breakpoints.
3976 * Changes in the DJGPP native configuration.
3978 New command ``info dos sysinfo'' displays assorted information about
3979 the CPU, OS, memory, and DPMI server.
3981 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3982 display information about segment descriptors stored in GDT, LDT, and
3985 New commands ``info dos pde'' and ``info dos pte'' display entries
3986 from Page Directory and Page Tables (for now works with CWSDPMI only).
3987 New command ``info dos address-pte'' displays the Page Table entry for
3988 a given linear address.
3990 GDB can now pass command lines longer than 126 characters to the
3991 program being debugged (requires an update to the libdbg.a library
3992 which is part of the DJGPP development kit).
3994 DWARF2 debug info is now supported.
3996 It is now possible to `step' and `next' through calls to `longjmp'.
3998 * Changes in documentation.
4000 All GDB documentation was converted to GFDL, the GNU Free
4001 Documentation License.
4003 Tracepoints-related commands are now fully documented in the GDB
4006 TUI, the Text-mode User Interface, is now documented in the manual.
4008 Tracepoints-related commands are now fully documented in the GDB
4011 The "GDB Internals" manual now has an index. It also includes
4012 documentation of `ui_out' functions, GDB coding standards, x86
4013 hardware watchpoints, and memory region attributes.
4015 * GDB's version number moved to ``version.in''
4017 The Makefile variable VERSION has been replaced by the file
4018 ``version.in''. People creating GDB distributions should update the
4019 contents of this file.
4023 GUD support is now a standard part of the EMACS distribution.
4025 *** Changes in GDB 5.0:
4027 * Improved support for debugging FP programs on x86 targets
4029 Unified and much-improved support for debugging floating-point
4030 programs on all x86 targets. In particular, ``info float'' now
4031 displays the FP registers in the same format on all x86 targets, with
4032 greater level of detail.
4034 * Improvements and bugfixes in hardware-assisted watchpoints
4036 It is now possible to watch array elements, struct members, and
4037 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4038 on x86 targets no longer erroneously trigger when the address is
4041 * Improvements in the native DJGPP version of GDB
4043 The distribution now includes all the scripts and auxiliary files
4044 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4045 machines ``out of the box''.
4047 The DJGPP version can now debug programs that use signals. It is
4048 possible to catch signals that happened in the debuggee, deliver
4049 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4050 would kill the program being debugged.) Programs that hook hardware
4051 interrupts (keyboard, timer, etc.) can also be debugged.
4053 It is now possible to debug DJGPP programs that redirect their
4054 standard handles or switch them to raw (as opposed to cooked) mode, or
4055 even close them. The command ``run < foo > bar'' works as expected,
4056 and ``info terminal'' reports useful information about the debuggee's
4057 terminal, including raw/cooked mode, redirection, etc.
4059 The DJGPP version now uses termios functions for console I/O, which
4060 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4063 DOS-style file names with drive letters are now fully supported by
4066 It is now possible to debug DJGPP programs that switch their working
4067 directory. It is also possible to rerun the debuggee any number of
4068 times without restarting GDB; thus, you can use the same setup,
4069 breakpoints, etc. for many debugging sessions.
4071 * New native configurations
4073 ARM GNU/Linux arm*-*-linux*
4074 PowerPC GNU/Linux powerpc-*-linux*
4078 Motorola MCore mcore-*-*
4079 x86 VxWorks i[3456]86-*-vxworks*
4080 PowerPC VxWorks powerpc-*-vxworks*
4081 TI TMS320C80 tic80-*-*
4083 * OBSOLETE configurations
4085 Altos 3068 m68*-altos-*
4086 Convex c1-*-*, c2-*-*
4088 ARM RISCix arm-*-* (as host)
4091 Configurations that have been declared obsolete will be commented out,
4092 but the code will be left in place. If there is no activity to revive
4093 these configurations before the next release of GDB, the sources will
4094 be permanently REMOVED.
4096 * Gould support removed
4098 Support for the Gould PowerNode and NP1 has been removed.
4100 * New features for SVR4
4102 On SVR4 native platforms (such as Solaris), if you attach to a process
4103 without first loading a symbol file, GDB will now attempt to locate and
4104 load symbols from the running process's executable file.
4106 * Many C++ enhancements
4108 C++ support has been greatly improved. Overload resolution now works properly
4109 in almost all cases. RTTI support is on the way.
4111 * Remote targets can connect to a sub-program
4113 A popen(3) style serial-device has been added. This device starts a
4114 sub-process (such as a stand-alone simulator) and then communicates
4115 with that. The sub-program to run is specified using the syntax
4116 ``|<program> <args>'' vis:
4118 (gdb) set remotedebug 1
4119 (gdb) target extended-remote |mn10300-elf-sim program-args
4121 * MIPS 64 remote protocol
4123 A long standing bug in the mips64 remote protocol where by GDB
4124 expected certain 32 bit registers (ex SR) to be transfered as 32
4125 instead of 64 bits has been fixed.
4127 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4128 added to provide backward compatibility with older versions of GDB.
4130 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4132 The command ``set remotebinarydownload'' command has been replaced by
4133 ``set remote X-packet''. Other commands in ``set remote'' family
4134 include ``set remote P-packet''.
4136 * Breakpoint commands accept ranges.
4138 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4139 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4140 ``tracepoint passcount'' also accepts a range of tracepoints.
4142 * ``apropos'' command added.
4144 The ``apropos'' command searches through command names and
4145 documentation strings, printing out matches, making it much easier to
4146 try to find a command that does what you are looking for.
4150 A new machine oriented interface (MI) has been added to GDB. This
4151 interface is designed for debug environments running GDB as a separate
4152 process. This is part of the long term libGDB project. See the
4153 "GDB/MI" chapter of the GDB manual for further information. It can be
4154 enabled by configuring with:
4156 .../configure --enable-gdbmi
4158 *** Changes in GDB-4.18:
4160 * New native configurations
4162 HP-UX 10.20 hppa*-*-hpux10.20
4163 HP-UX 11.x hppa*-*-hpux11.0*
4164 M68K GNU/Linux m68*-*-linux*
4168 Fujitsu FR30 fr30-*-elf*
4169 Intel StrongARM strongarm-*-*
4170 Mitsubishi D30V d30v-*-*
4172 * OBSOLETE configurations
4174 Gould PowerNode, NP1 np1-*-*, pn-*-*
4176 Configurations that have been declared obsolete will be commented out,
4177 but the code will be left in place. If there is no activity to revive
4178 these configurations before the next release of GDB, the sources will
4179 be permanently REMOVED.
4183 As a compatibility experiment, GDB's source files buildsym.h and
4184 buildsym.c have been converted to pure standard C, no longer
4185 containing any K&R compatibility code. We believe that all systems in
4186 use today either come with a standard C compiler, or have a GCC port
4187 available. If this is not true, please report the affected
4188 configuration to bug-gdb@gnu.org immediately. See the README file for
4189 information about getting a standard C compiler if you don't have one
4194 GDB now uses readline 2.2.
4196 * set extension-language
4198 You can now control the mapping between filename extensions and source
4199 languages by using the `set extension-language' command. For instance,
4200 you can ask GDB to treat .c files as C++ by saying
4201 set extension-language .c c++
4202 The command `info extensions' lists all of the recognized extensions
4203 and their associated languages.
4205 * Setting processor type for PowerPC and RS/6000
4207 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4208 you can use the `set processor' command to specify what variant of the
4209 PowerPC family you are debugging. The command
4213 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4214 following PowerPC and RS6000 variants:
4216 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4217 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4219 403GC IBM PowerPC 403GC
4220 505 Motorola PowerPC 505
4221 860 Motorola PowerPC 860 or 850
4222 601 Motorola PowerPC 601
4223 602 Motorola PowerPC 602
4224 603 Motorola/IBM PowerPC 603 or 603e
4225 604 Motorola PowerPC 604 or 604e
4226 750 Motorola/IBM PowerPC 750 or 750
4228 At the moment, this command just tells GDB what to name the
4229 special-purpose processor registers. Since almost all the affected
4230 registers are inaccessible to user-level programs, this command is
4231 only useful for remote debugging in its present form.
4235 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4236 more extensive support for HP-UX. Added features include shared
4237 library support, kernel threads and hardware watchpoints for 11.00,
4238 support for HP's ANSI C and C++ compilers, and a compatibility mode
4239 for xdb and dbx commands.
4243 HP's donation includes the new concept of catchpoints, which is a
4244 generalization of the old catch command. On HP-UX, it is now possible
4245 to catch exec, fork, and vfork, as well as library loading.
4247 This means that the existing catch command has changed; its first
4248 argument now specifies the type of catch to be set up. See the
4249 output of "help catch" for a list of catchpoint types.
4251 * Debugging across forks
4253 On HP-UX, you can choose which process to debug when a fork() happens
4258 HP has donated a curses-based terminal user interface (TUI). To get
4259 it, build with --enable-tui. Although this can be enabled for any
4260 configuration, at present it only works for native HP debugging.
4262 * GDB remote protocol additions
4264 A new protocol packet 'X' that writes binary data is now available.
4265 Default behavior is to try 'X', then drop back to 'M' if the stub
4266 fails to respond. The settable variable `remotebinarydownload'
4267 allows explicit control over the use of 'X'.
4269 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4270 full 64-bit address. The command
4272 set remoteaddresssize 32
4274 can be used to revert to the old behaviour. For existing remote stubs
4275 the change should not be noticed, as the additional address information
4278 In order to assist in debugging stubs, you may use the maintenance
4279 command `packet' to send any text string to the stub. For instance,
4281 maint packet heythere
4283 sends the packet "$heythere#<checksum>". Note that it is very easy to
4284 disrupt a debugging session by sending the wrong packet at the wrong
4287 The compare-sections command allows you to compare section data on the
4288 target to what is in the executable file without uploading or
4289 downloading, by comparing CRC checksums.
4291 * Tracing can collect general expressions
4293 You may now collect general expressions at tracepoints. This requires
4294 further additions to the target-side stub; see tracepoint.c and
4295 doc/agentexpr.texi for further details.
4297 * mask-address variable for Mips
4299 For Mips targets, you may control the zeroing of the upper 32 bits of
4300 a 64-bit address by entering `set mask-address on'. This is mainly
4301 of interest to users of embedded R4xxx and R5xxx processors.
4303 * Higher serial baud rates
4305 GDB's serial code now allows you to specify baud rates 57600, 115200,
4306 230400, and 460800 baud. (Note that your host system may not be able
4307 to achieve all of these rates.)
4311 The i960 configuration now includes an initial implementation of a
4312 builtin simulator, contributed by Jim Wilson.
4315 *** Changes in GDB-4.17:
4317 * New native configurations
4319 Alpha GNU/Linux alpha*-*-linux*
4320 Unixware 2.x i[3456]86-unixware2*
4321 Irix 6.x mips*-sgi-irix6*
4322 PowerPC GNU/Linux powerpc-*-linux*
4323 PowerPC Solaris powerpcle-*-solaris*
4324 Sparc GNU/Linux sparc-*-linux*
4325 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4329 Argonaut Risc Chip (ARC) arc-*-*
4330 Hitachi H8/300S h8300*-*-*
4331 Matsushita MN10200 w/simulator mn10200-*-*
4332 Matsushita MN10300 w/simulator mn10300-*-*
4333 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4334 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4335 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4336 Mitsubishi D10V w/simulator d10v-*-*
4337 Mitsubishi M32R/D w/simulator m32r-*-elf*
4338 Tsqware Sparclet sparclet-*-*
4339 NEC V850 w/simulator v850-*-*
4341 * New debugging protocols
4343 ARM with RDI protocol arm*-*-*
4344 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4345 DDB and LSI variants of PMON protocol mips*-*-*
4346 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4347 PowerPC with SDS protocol powerpc{,le}-*-eabi
4348 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4352 All configurations can now understand and use the DWARF 2 debugging
4353 format. The choice is automatic, if the symbol file contains DWARF 2
4358 GDB now includes basic Java language support. This support is
4359 only useful with Java compilers that produce native machine code.
4361 * solib-absolute-prefix and solib-search-path
4363 For SunOS and SVR4 shared libraries, you may now set the prefix for
4364 loading absolute shared library symbol files, and the search path for
4365 locating non-absolute shared library symbol files.
4367 * Live range splitting
4369 GDB can now effectively debug code for which GCC has performed live
4370 range splitting as part of its optimization. See gdb/doc/LRS for
4371 more details on the expected format of the stabs information.
4375 GDB's support for the GNU Hurd, including thread debugging, has been
4376 updated to work with current versions of the Hurd.
4380 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4381 instruction set. ARM GDB automatically detects when Thumb
4382 instructions are in use, and adjusts disassembly and backtracing
4387 GDB's MIPS target configurations now handle the MIP16 16-bit
4392 GDB now includes support for overlays; if an executable has been
4393 linked such that multiple sections are based at the same address, GDB
4394 will decide which section to use for symbolic info. You can choose to
4395 control the decision manually, using overlay commands, or implement
4396 additional target-side support and use "overlay load-target" to bring
4397 in the overlay mapping. Do "help overlay" for more detail.
4401 The command "info symbol <address>" displays information about
4402 the symbol at the specified address.
4406 The standard remote protocol now includes an extension that allows
4407 asynchronous collection and display of trace data. This requires
4408 extensive support in the target-side debugging stub. Tracing mode
4409 includes a new interaction mode in GDB and new commands: see the
4410 file tracepoint.c for more details.
4414 Configurations for embedded MIPS now include a simulator contributed
4415 by Cygnus Solutions. The simulator supports the instruction sets
4416 of most MIPS variants.
4420 Sparc configurations may now include the ERC32 simulator contributed
4421 by the European Space Agency. The simulator is not built into
4422 Sparc targets by default; configure with --enable-sim to include it.
4426 For target configurations that may include multiple variants of a
4427 basic architecture (such as MIPS and SH), you may now set the
4428 architecture explicitly. "set arch" sets, "info arch" lists
4429 the possible architectures.
4431 *** Changes in GDB-4.16:
4433 * New native configurations
4435 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4436 M68K NetBSD m68k-*-netbsd*
4437 PowerPC AIX 4.x powerpc-*-aix*
4438 PowerPC MacOS powerpc-*-macos*
4439 PowerPC Windows NT powerpcle-*-cygwin32
4440 RS/6000 AIX 4.x rs6000-*-aix4*
4444 ARM with RDP protocol arm-*-*
4445 I960 with MON960 i960-*-coff
4446 MIPS VxWorks mips*-*-vxworks*
4447 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4448 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4450 Matra Sparclet sparclet-*-*
4454 The powerpc-eabi configuration now includes the PSIM simulator,
4455 contributed by Andrew Cagney, with assistance from Mike Meissner.
4456 PSIM is a very elaborate model of the PowerPC, including not only
4457 basic instruction set execution, but also details of execution unit
4458 performance and I/O hardware. See sim/ppc/README for more details.
4462 GDB now works with Solaris 2.5.
4464 * Windows 95/NT native
4466 GDB will now work as a native debugger on Windows 95 and Windows NT.
4467 To build it from source, you must use the "gnu-win32" environment,
4468 which uses a DLL to emulate enough of Unix to run the GNU tools.
4469 Further information, binaries, and sources are available at
4470 ftp.cygnus.com, under pub/gnu-win32.
4472 * dont-repeat command
4474 If a user-defined command includes the command `dont-repeat', then the
4475 command will not be repeated if the user just types return. This is
4476 useful if the command is time-consuming to run, so that accidental
4477 extra keystrokes don't run the same command many times.
4479 * Send break instead of ^C
4481 The standard remote protocol now includes an option to send a break
4482 rather than a ^C to the target in order to interrupt it. By default,
4483 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4485 * Remote protocol timeout
4487 The standard remote protocol includes a new variable `remotetimeout'
4488 that allows you to set the number of seconds before GDB gives up trying
4489 to read from the target. The default value is 2.
4491 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4493 By default GDB will automatically keep track of objects as they are
4494 loaded and unloaded by the dynamic linker. By using the command `set
4495 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4496 when shared library events occur, thus allowing you to set breakpoints
4497 in shared libraries which are explicitly loaded by the inferior.
4499 Note this feature does not work on hpux8. On hpux9 you must link
4500 /usr/lib/end.o into your program. This feature should work
4501 automatically on hpux10.
4503 * Irix 5.x hardware watchpoint support
4505 Irix 5 configurations now support the use of hardware watchpoints.
4507 * Mips protocol "SYN garbage limit"
4509 When debugging a Mips target using the `target mips' protocol, you
4510 may set the number of characters that GDB will ignore by setting
4511 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4512 every character. The default value is 1050.
4514 * Recording and replaying remote debug sessions
4516 If you set `remotelogfile' to the name of a file, gdb will write to it
4517 a recording of a remote debug session. This recording may then be
4518 replayed back to gdb using "gdbreplay". See gdbserver/README for
4519 details. This is useful when you have a problem with GDB while doing
4520 remote debugging; you can make a recording of the session and send it
4521 to someone else, who can then recreate the problem.
4523 * Speedups for remote debugging
4525 GDB includes speedups for downloading and stepping MIPS systems using
4526 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4527 and more efficient S-record downloading.
4529 * Memory use reductions and statistics collection
4531 GDB now uses less memory and reports statistics about memory usage.
4532 Try the `maint print statistics' command, for example.
4534 *** Changes in GDB-4.15:
4536 * Psymtabs for XCOFF
4538 The symbol reader for AIX GDB now uses partial symbol tables. This
4539 can greatly improve startup time, especially for large executables.
4541 * Remote targets use caching
4543 Remote targets now use a data cache to speed up communication with the
4544 remote side. The data cache could lead to incorrect results because
4545 it doesn't know about volatile variables, thus making it impossible to
4546 debug targets which use memory mapped I/O devices. `set remotecache
4547 off' turns the the data cache off.
4549 * Remote targets may have threads
4551 The standard remote protocol now includes support for multiple threads
4552 in the target system, using new protocol commands 'H' and 'T'. See
4553 gdb/remote.c for details.
4557 If GDB is configured with `--enable-netrom', then it will include
4558 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4559 acts as though it is a bank of ROM on the target board, but you can
4560 write into it over the network. GDB's support consists only of
4561 support for fast loading into the emulated ROM; to debug, you must use
4562 another protocol, such as standard remote protocol. The usual
4563 sequence is something like
4565 target nrom <netrom-hostname>
4567 target remote <netrom-hostname>:1235
4571 GDB now includes support for the Apple Macintosh, as a host only. It
4572 may be run as either an MPW tool or as a standalone application, and
4573 it can debug through the serial port. All the usual GDB commands are
4574 available, but to the target command, you must supply "serial" as the
4575 device type instead of "/dev/ttyXX". See mpw-README in the main
4576 directory for more information on how to build. The MPW configuration
4577 scripts */mpw-config.in support only a few targets, and only the
4578 mips-idt-ecoff target has been tested.
4582 GDB configuration now uses autoconf. This is not user-visible,
4583 but does simplify configuration and building.
4587 GDB now supports hpux10.
4589 *** Changes in GDB-4.14:
4591 * New native configurations
4593 x86 FreeBSD i[345]86-*-freebsd
4594 x86 NetBSD i[345]86-*-netbsd
4595 NS32k NetBSD ns32k-*-netbsd
4596 Sparc NetBSD sparc-*-netbsd
4600 A29K VxWorks a29k-*-vxworks
4601 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4602 CPU32 EST-300 emulator m68*-*-est*
4603 PowerPC ELF powerpc-*-elf
4606 * Alpha OSF/1 support for procfs
4608 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4609 possible to attach to running processes. As the mounting of the /proc
4610 filesystem is optional on the Alpha, GDB automatically determines
4611 the availability of /proc during startup. This can lead to problems
4612 if /proc is unmounted after GDB has been started.
4614 * Arguments to user-defined commands
4616 User commands may accept up to 10 arguments separated by whitespace.
4617 Arguments are accessed within the user command via $arg0..$arg9. A
4620 print $arg0 + $arg1 + $arg2
4622 To execute the command use:
4625 Defines the command "adder" which prints the sum of its three arguments.
4626 Note the arguments are text substitutions, so they may reference variables,
4627 use complex expressions, or even perform inferior function calls.
4629 * New `if' and `while' commands
4631 This makes it possible to write more sophisticated user-defined
4632 commands. Both commands take a single argument, which is the
4633 expression to evaluate, and must be followed by the commands to
4634 execute, one per line, if the expression is nonzero, the list being
4635 terminated by the word `end'. The `if' command list may include an
4636 `else' word, which causes the following commands to be executed only
4637 if the expression is zero.
4639 * Fortran source language mode
4641 GDB now includes partial support for Fortran 77. It will recognize
4642 Fortran programs and can evaluate a subset of Fortran expressions, but
4643 variables and functions may not be handled correctly. GDB will work
4644 with G77, but does not yet know much about symbols emitted by other
4647 * Better HPUX support
4649 Most debugging facilities now work on dynamic executables for HPPAs
4650 running hpux9 or later. You can attach to running dynamically linked
4651 processes, but by default the dynamic libraries will be read-only, so
4652 for instance you won't be able to put breakpoints in them. To change
4653 that behavior do the following before running the program:
4659 This will cause the libraries to be mapped private and read-write.
4660 To revert to the normal behavior, do this:
4666 You cannot set breakpoints or examine data in the library until after
4667 the library is loaded if the function/data symbols do not have
4670 GDB can now also read debug symbols produced by the HP C compiler on
4671 HPPAs (sorry, no C++, Fortran or 68k support).
4673 * Target byte order now dynamically selectable
4675 You can choose which byte order to use with a target system, via the
4676 commands "set endian big" and "set endian little", and you can see the
4677 current setting by using "show endian". You can also give the command
4678 "set endian auto", in which case GDB will use the byte order
4679 associated with the executable. Currently, only embedded MIPS
4680 configurations support dynamic selection of target byte order.
4682 * New DOS host serial code
4684 This version uses DPMI interrupts to handle buffered I/O, so you
4685 no longer need to run asynctsr when debugging boards connected to
4688 *** Changes in GDB-4.13:
4690 * New "complete" command
4692 This lists all the possible completions for the rest of the line, if it
4693 were to be given as a command itself. This is intended for use by emacs.
4695 * Trailing space optional in prompt
4697 "set prompt" no longer adds a space for you after the prompt you set. This
4698 allows you to set a prompt which ends in a space or one that does not.
4700 * Breakpoint hit counts
4702 "info break" now displays a count of the number of times the breakpoint
4703 has been hit. This is especially useful in conjunction with "ignore"; you
4704 can ignore a large number of breakpoint hits, look at the breakpoint info
4705 to see how many times the breakpoint was hit, then run again, ignoring one
4706 less than that number, and this will get you quickly to the last hit of
4709 * Ability to stop printing at NULL character
4711 "set print null-stop" will cause GDB to stop printing the characters of
4712 an array when the first NULL is encountered. This is useful when large
4713 arrays actually contain only short strings.
4715 * Shared library breakpoints
4717 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4718 breakpoints in shared libraries before the executable is run.
4720 * Hardware watchpoints
4722 There is a new hardware breakpoint for the watch command for sparclite
4723 targets. See gdb/sparclite/hw_breakpoint.note.
4725 Hardware watchpoints are also now supported under GNU/Linux.
4729 Annotations have been added. These are for use with graphical interfaces,
4730 and are still experimental. Currently only gdba.el uses these.
4732 * Improved Irix 5 support
4734 GDB now works properly with Irix 5.2.
4736 * Improved HPPA support
4738 GDB now works properly with the latest GCC and GAS.
4740 * New native configurations
4742 Sequent PTX4 i[34]86-sequent-ptx4
4743 HPPA running OSF/1 hppa*-*-osf*
4744 Atari TT running SVR4 m68*-*-sysv4*
4745 RS/6000 LynxOS rs6000-*-lynxos*
4749 OS/9000 i[34]86-*-os9k
4750 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4753 * Hitachi SH7000 and E7000-PC ICE support
4755 There is now support for communicating with the Hitachi E7000-PC ICE.
4756 This is available automatically when GDB is configured for the SH.
4760 As usual, a variety of small fixes and improvements, both generic
4761 and configuration-specific. See the ChangeLog for more detail.
4763 *** Changes in GDB-4.12:
4765 * Irix 5 is now supported
4769 GDB-4.12 on the HPPA has a number of changes which make it unable
4770 to debug the output from the currently released versions of GCC and
4771 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4772 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4773 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4776 *** Changes in GDB-4.11:
4778 * User visible changes:
4782 The "set remotedebug" option is now consistent between the mips remote
4783 target, remote targets using the gdb-specific protocol, UDI (AMD's
4784 debug protocol for the 29k) and the 88k bug monitor. It is now an
4785 integer specifying a debug level (normally 0 or 1, but 2 means more
4786 debugging info for the mips target).
4788 * DEC Alpha native support
4790 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4791 debug info, but GDB works fairly well with the DEC compiler and should
4792 work with a future GCC release. See the README file for a few
4793 Alpha-specific notes.
4795 * Preliminary thread implementation
4797 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4799 * LynxOS native and target support for 386
4801 This release has been hosted on LynxOS 2.2, and also can be configured
4802 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4805 * Improvements in C++ mangling/demangling.
4807 This release has much better g++ debugging, specifically in name
4808 mangling/demangling, virtual function calls, print virtual table,
4809 call methods, ...etc.
4811 *** Changes in GDB-4.10:
4813 * User visible changes:
4815 Remote debugging using the GDB-specific (`target remote') protocol now
4816 supports the `load' command. This is only useful if you have some
4817 other way of getting the stub to the target system, and you can put it
4818 somewhere in memory where it won't get clobbered by the download.
4820 Filename completion now works.
4822 When run under emacs mode, the "info line" command now causes the
4823 arrow to point to the line specified. Also, "info line" prints
4824 addresses in symbolic form (as well as hex).
4826 All vxworks based targets now support a user settable option, called
4827 vxworks-timeout. This option represents the number of seconds gdb
4828 should wait for responses to rpc's. You might want to use this if
4829 your vxworks target is, perhaps, a slow software simulator or happens
4830 to be on the far side of a thin network line.
4834 This release contains support for using a DEC alpha as a GDB host for
4835 cross debugging. Native alpha debugging is not supported yet.
4838 *** Changes in GDB-4.9:
4842 This is the first GDB release which is accompanied by a matching testsuite.
4843 The testsuite requires installation of dejagnu, which should be available
4844 via ftp from most sites that carry GNU software.
4848 'Cfront' style demangling has had its name changed to 'ARM' style, to
4849 emphasize that it was written from the specifications in the C++ Annotated
4850 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4851 disclaimers, it still generated too much confusion with users attempting to
4852 use gdb with AT&T cfront.
4856 GDB now uses a standard remote interface to a simulator library.
4857 So far, the library contains simulators for the Zilog Z8001/2, the
4858 Hitachi H8/300, H8/500 and Super-H.
4860 * New targets supported
4862 H8/300 simulator h8300-hitachi-hms or h8300hms
4863 H8/500 simulator h8500-hitachi-hms or h8500hms
4864 SH simulator sh-hitachi-hms or sh
4865 Z8000 simulator z8k-zilog-none or z8ksim
4866 IDT MIPS board over serial line mips-idt-ecoff
4868 Cross-debugging to GO32 targets is supported. It requires a custom
4869 version of the i386-stub.c module which is integrated with the
4870 GO32 memory extender.
4872 * New remote protocols
4874 MIPS remote debugging protocol.
4876 * New source languages supported
4878 This version includes preliminary support for Chill, a Pascal like language
4879 used by telecommunications companies. Chill support is also being integrated
4880 into the GNU compiler, but we don't know when it will be publically available.
4883 *** Changes in GDB-4.8:
4885 * HP Precision Architecture supported
4887 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4888 version of this support was available as a set of patches from the
4889 University of Utah. GDB does not support debugging of programs
4890 compiled with the HP compiler, because HP will not document their file
4891 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4892 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4894 Many problems in the preliminary version have been fixed.
4896 * Faster and better demangling
4898 We have improved template demangling and fixed numerous bugs in the GNU style
4899 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4900 character types (wchar_t) are now supported. Demangling of each symbol is now
4901 only done once, and is cached when the symbol table for a file is read in.
4902 This results in a small increase in memory usage for C programs, a moderate
4903 increase in memory usage for C++ programs, and a fantastic speedup in
4906 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4907 from the specifications in the Annotated Reference Manual, which AT&T's
4908 compiler does not actually implement.
4910 * G++ multiple inheritance compiler problem
4912 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4913 inheritance lattices was reworked to properly discover ambiguities. We
4914 recently found an example which causes this new algorithm to fail in a
4915 very subtle way, producing bad debug information for those classes.
4916 The file 'gcc.patch' (in this directory) can be applied to gcc to
4917 circumvent the problem. A future GCC release will contain a complete
4920 The previous G++ debug info problem (mentioned below for the gdb-4.7
4921 release) is fixed in gcc version 2.3.2.
4923 * Improved configure script
4925 The `configure' script will now attempt to guess your system type if
4926 you don't supply a host system type. The old scheme of supplying a
4927 host system triplet is preferable over using this. All the magic is
4928 done in the new `config.guess' script. Examine it for details.
4930 We have also brought our configure script much more in line with the FSF's
4931 version. It now supports the --with-xxx options. In particular,
4932 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4933 The resulting GDB will not be able to read arbitrary object file formats --
4934 only the format ``expected'' to be used on the configured target system.
4935 We hope to make this the default in a future release.
4937 * Documentation improvements
4939 There's new internal documentation on how to modify GDB, and how to
4940 produce clean changes to the code. We implore people to read it
4941 before submitting changes.
4943 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4944 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4945 `info' files are also provided. To build `info' files from scratch,
4946 you will need the latest `makeinfo' release, which will be available in
4947 a future texinfo-X.Y release.
4949 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4950 We're not sure exactly which versions have this problem, but it has
4951 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4952 or better. If that isn't possible, there is a patch in
4953 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4954 around this problem.
4958 GDB now supports array constants that can be used in expressions typed in by
4959 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4960 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4963 The new directory `gdb/sparclite' contains a program that demonstrates
4964 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4966 * New native hosts supported
4968 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4969 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4971 * New targets supported
4973 AMD 29k family via UDI a29k-amd-udi or udi29k
4975 * New file formats supported
4977 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4978 HPUX core files, and SCO 3.2v2 core files.
4982 Attaching to processes now works again; thanks for the many bug reports.
4984 We have also stomped on a bunch of core dumps caused by
4985 printf_filtered("%s") problems.
4987 We eliminated a copyright problem on the rpc and ptrace header files
4988 for VxWorks, which was discovered at the last minute during the 4.7
4989 release. You should now be able to build a VxWorks GDB.
4991 You can now interrupt gdb while an attached process is running. This
4992 will cause the attached process to stop, and give control back to GDB.
4994 We fixed problems caused by using too many file descriptors
4995 for reading symbols from object files and libraries. This was
4996 especially a problem for programs that used many (~100) shared
4999 The `step' command now only enters a subroutine if there is line number
5000 information for the subroutine. Otherwise it acts like the `next'
5001 command. Previously, `step' would enter subroutines if there was
5002 any debugging information about the routine. This avoids problems
5003 when using `cc -g1' on MIPS machines.
5005 * Internal improvements
5007 GDB's internal interfaces have been improved to make it easier to support
5008 debugging of multiple languages in the future.
5010 GDB now uses a common structure for symbol information internally.
5011 Minimal symbols (derived from linkage symbols in object files), partial
5012 symbols (from a quick scan of debug information), and full symbols
5013 contain a common subset of information, making it easier to write
5014 shared code that handles any of them.
5016 * New command line options
5018 We now accept --silent as an alias for --quiet.
5022 The memory-mapped-malloc library is now licensed under the GNU Library
5023 General Public License.
5025 *** Changes in GDB-4.7:
5027 * Host/native/target split
5029 GDB has had some major internal surgery to untangle the support for
5030 hosts and remote targets. Now, when you configure GDB for a remote
5031 target, it will no longer load in all of the support for debugging
5032 local programs on the host. When fully completed and tested, this will
5033 ensure that arbitrary host/target combinations are possible.
5035 The primary conceptual shift is to separate the non-portable code in
5036 GDB into three categories. Host specific code is required any time GDB
5037 is compiled on that host, regardless of the target. Target specific
5038 code relates to the peculiarities of the target, but can be compiled on
5039 any host. Native specific code is everything else: it can only be
5040 built when the host and target are the same system. Child process
5041 handling and core file support are two common `native' examples.
5043 GDB's use of /proc for controlling Unix child processes is now cleaner.
5044 It has been split out into a single module under the `target_ops' vector,
5045 plus two native-dependent functions for each system that uses /proc.
5047 * New hosts supported
5049 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5050 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5051 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5053 * New targets supported
5055 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5056 68030 and CPU32 m68030-*-*, m68332-*-*
5058 * New native hosts supported
5060 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5061 (386bsd is not well tested yet)
5062 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5064 * New file formats supported
5066 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5067 supports reading of `a.out.adobe' object files, which are an a.out
5068 format extended with minimal information about multiple sections.
5072 `show copying' is the same as the old `info copying'.
5073 `show warranty' is the same as `info warrantee'.
5074 These were renamed for consistency. The old commands continue to work.
5076 `info handle' is a new alias for `info signals'.
5078 You can now define pre-command hooks, which attach arbitrary command
5079 scripts to any command. The commands in the hook will be executed
5080 prior to the user's command. You can also create a hook which will be
5081 executed whenever the program stops. See gdb.texinfo.
5085 We now deal with Cfront style name mangling, and can even extract type
5086 info from mangled symbols. GDB can automatically figure out which
5087 symbol mangling style your C++ compiler uses.
5089 Calling of methods and virtual functions has been improved as well.
5093 The crash that occured when debugging Sun Ansi-C compiled binaries is
5094 fixed. This was due to mishandling of the extra N_SO stabs output
5097 We also finally got Ultrix 4.2 running in house, and fixed core file
5098 support, with help from a dozen people on the net.
5100 John M. Farrell discovered that the reason that single-stepping was so
5101 slow on all of the Mips based platforms (primarily SGI and DEC) was
5102 that we were trying to demangle and lookup a symbol used for internal
5103 purposes on every instruction that was being stepped through. Changing
5104 the name of that symbol so that it couldn't be mistaken for a C++
5105 mangled symbol sped things up a great deal.
5107 Rich Pixley sped up symbol lookups in general by getting much smarter
5108 about when C++ symbol mangling is necessary. This should make symbol
5109 completion (TAB on the command line) much faster. It's not as fast as
5110 we'd like, but it's significantly faster than gdb-4.6.
5114 A new user controllable variable 'call_scratch_address' can
5115 specify the location of a scratch area to be used when GDB
5116 calls a function in the target. This is necessary because the
5117 usual method of putting the scratch area on the stack does not work
5118 in systems that have separate instruction and data spaces.
5120 We integrated changes to support the 29k UDI (Universal Debugger
5121 Interface), but discovered at the last minute that we didn't have all
5122 of the appropriate copyright paperwork. We are working with AMD to
5123 resolve this, and hope to have it available soon.
5127 We have sped up the remote serial line protocol, especially for targets
5128 with lots of registers. It now supports a new `expedited status' ('T')
5129 message which can be used in place of the existing 'S' status message.
5130 This allows the remote stub to send only the registers that GDB
5131 needs to make a quick decision about single-stepping or conditional
5132 breakpoints, eliminating the need to fetch the entire register set for
5133 each instruction being stepped through.
5135 The GDB remote serial protocol now implements a write-through cache for
5136 registers, only re-reading the registers if the target has run.
5138 There is also a new remote serial stub for SPARC processors. You can
5139 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5140 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5141 processor with a serial port.
5145 Configure.in files have become much easier to read and modify. A new
5146 `table driven' format makes it more obvious what configurations are
5147 supported, and what files each one uses.
5151 There is a new opcodes library which will eventually contain all of the
5152 disassembly routines and opcode tables. At present, it only contains
5153 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5154 disassembler (binutils/objdump) to share these routines.
5156 The libiberty library is now copylefted under the GNU Library General
5157 Public License. This allows more liberal use, and was done so libg++
5158 can use it. This makes no difference to GDB, since the Library License
5159 grants all the rights from the General Public License.
5163 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5164 reference to the stabs symbol info used by the debugger. It is (as far
5165 as we know) the only published document on this fascinating topic. We
5166 encourage you to read it, compare it to the stabs information on your
5167 system, and send improvements on the document in general (to
5168 bug-gdb@prep.ai.mit.edu).
5170 And, of course, many bugs have been fixed.
5173 *** Changes in GDB-4.6:
5175 * Better support for C++ function names
5177 GDB now accepts as input the "demangled form" of C++ overloaded function
5178 names and member function names, and can do command completion on such names
5179 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5180 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5181 Make use of command completion, it is your friend.
5183 GDB also now accepts a variety of C++ mangled symbol formats. They are
5184 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5185 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5186 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5187 for the list of formats.
5189 * G++ symbol mangling problem
5191 Recent versions of gcc have a bug in how they emit debugging information for
5192 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5193 directory) can be applied to gcc to fix the problem. Alternatively, if you
5194 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5195 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5196 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5199 * New 'maintenance' command
5201 All of the commands related to hacking GDB internals have been moved out of
5202 the main command set, and now live behind the 'maintenance' command. This
5203 can also be abbreviated as 'mt'. The following changes were made:
5205 dump-me -> maintenance dump-me
5206 info all-breakpoints -> maintenance info breakpoints
5207 printmsyms -> maintenance print msyms
5208 printobjfiles -> maintenance print objfiles
5209 printpsyms -> maintenance print psymbols
5210 printsyms -> maintenance print symbols
5212 The following commands are new:
5214 maintenance demangle Call internal GDB demangler routine to
5215 demangle a C++ link name and prints the result.
5216 maintenance print type Print a type chain for a given symbol
5218 * Change to .gdbinit file processing
5220 We now read the $HOME/.gdbinit file before processing the argv arguments
5221 (e.g. reading symbol files or core files). This allows global parameters to
5222 be set, which will apply during the symbol reading. The ./.gdbinit is still
5223 read after argv processing.
5225 * New hosts supported
5227 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5229 GNU/Linux support i386-unknown-linux or linux
5231 We are also including code to support the HP/PA running BSD and HPUX. This
5232 is almost guaranteed not to work, as we didn't have time to test or build it
5233 for this release. We are including it so that the more adventurous (or
5234 masochistic) of you can play with it. We also had major problems with the
5235 fact that the compiler that we got from HP doesn't support the -g option.
5238 * New targets supported
5240 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5242 * More smarts about finding #include files
5244 GDB now remembers the compilation directory for all include files, and for
5245 all files from which C is generated (like yacc and lex sources). This
5246 greatly improves GDB's ability to find yacc/lex sources, and include files,
5247 especially if you are debugging your program from a directory different from
5248 the one that contains your sources.
5250 We also fixed a bug which caused difficulty with listing and setting
5251 breakpoints in include files which contain C code. (In the past, you had to
5252 try twice in order to list an include file that you hadn't looked at before.)
5254 * Interesting infernals change
5256 GDB now deals with arbitrary numbers of sections, where the symbols for each
5257 section must be relocated relative to that section's landing place in the
5258 target's address space. This work was needed to support ELF with embedded
5259 stabs used by Solaris-2.0.
5261 * Bug fixes (of course!)
5263 There have been loads of fixes for the following things:
5264 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5265 i960, stabs, DOS(GO32), procfs, etc...
5267 See the ChangeLog for details.
5269 *** Changes in GDB-4.5:
5271 * New machines supported (host and target)
5273 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5275 SGI Irix-4.x mips-sgi-irix4 or iris4
5277 * New malloc package
5279 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5280 Mmalloc is capable of handling mutiple heaps of memory. It is also
5281 capable of saving a heap to a file, and then mapping it back in later.
5282 This can be used to greatly speedup the startup of GDB by using a
5283 pre-parsed symbol table which lives in a mmalloc managed heap. For
5284 more details, please read mmalloc/mmalloc.texi.
5288 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5289 'help info proc' for details.
5291 * MIPS ecoff symbol table format
5293 The code that reads MIPS symbol table format is now supported on all hosts.
5294 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5297 * File name changes for MS-DOS
5299 Many files in the config directories have been renamed to make it easier to
5300 support GDB on MS-DOSe systems (which have very restrictive file name
5301 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5302 environment) is close to working but has some remaining problems. Note
5303 that debugging of DOS programs is not supported, due to limitations
5304 in the ``operating system'', but it can be used to host cross-debugging.
5306 * Cross byte order fixes
5308 Many fixes have been made to support cross debugging of Sparc and MIPS
5309 targets from hosts whose byte order differs.
5311 * New -mapped and -readnow options
5313 If memory-mapped files are available on your system through the 'mmap'
5314 system call, you can use the -mapped option on the `file' or
5315 `symbol-file' commands to cause GDB to write the symbols from your
5316 program into a reusable file. If the program you are debugging is
5317 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5318 Future GDB debugging sessions will notice the presence of this file,
5319 and will quickly map in symbol information from it, rather than reading
5320 the symbol table from the executable program. Using the '-mapped'
5321 option in a GDB `file' or `symbol-file' command has the same effect as
5322 starting GDB with the '-mapped' command-line option.
5324 You can cause GDB to read the entire symbol table immediately by using
5325 the '-readnow' option with any of the commands that load symbol table
5326 information (or on the GDB command line). This makes the command
5327 slower, but makes future operations faster.
5329 The -mapped and -readnow options are typically combined in order to
5330 build a `fred.syms' file that contains complete symbol information.
5331 A simple GDB invocation to do nothing but build a `.syms' file for future
5334 gdb -batch -nx -mapped -readnow programname
5336 The `.syms' file is specific to the host machine on which GDB is run.
5337 It holds an exact image of GDB's internal symbol table. It cannot be
5338 shared across multiple host platforms.
5340 * longjmp() handling
5342 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5343 siglongjmp() without losing control. This feature has not yet been ported to
5344 all systems. It currently works on many 386 platforms, all MIPS-based
5345 platforms (SGI, DECstation, etc), and Sun3/4.
5349 Preliminary work has been put in to support the new Solaris OS from Sun. At
5350 this time, it can control and debug processes, but it is not capable of
5355 As always, many many bug fixes. The major areas were with g++, and mipsread.
5356 People using the MIPS-based platforms should experience fewer mysterious
5357 crashes and trashed symbol tables.
5359 *** Changes in GDB-4.4:
5361 * New machines supported (host and target)
5363 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5365 BSD Reno on Vax vax-dec-bsd
5366 Ultrix on Vax vax-dec-ultrix
5368 * New machines supported (target)
5370 AMD 29000 embedded, using EBMON a29k-none-none
5374 GDB continues to improve its handling of C++. `References' work better.
5375 The demangler has also been improved, and now deals with symbols mangled as
5376 per the Annotated C++ Reference Guide.
5378 GDB also now handles `stabs' symbol information embedded in MIPS
5379 `ecoff' symbol tables. Since the ecoff format was not easily
5380 extensible to handle new languages such as C++, this appeared to be a
5381 good way to put C++ debugging info into MIPS binaries. This option
5382 will be supported in the GNU C compiler, version 2, when it is
5385 * New features for SVR4
5387 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5388 shared libraries. Debugging dynamically linked programs should present
5389 only minor differences from debugging statically linked programs.
5391 The `info proc' command will print out information about any process
5392 on an SVR4 system (including the one you are debugging). At the moment,
5393 it prints the address mappings of the process.
5395 If you bring up GDB on another SVR4 system, please send mail to
5396 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5398 * Better dynamic linking support in SunOS
5400 Reading symbols from shared libraries which contain debugging symbols
5401 now works properly. However, there remain issues such as automatic
5402 skipping of `transfer vector' code during function calls, which
5403 make it harder to debug code in a shared library, than to debug the
5404 same code linked statically.
5408 GDB is now using the latest `getopt' routines from the FSF. This
5409 version accepts the -- prefix for options with long names. GDB will
5410 continue to accept the old forms (-option and +option) as well.
5411 Various single letter abbreviations for options have been explicity
5412 added to the option table so that they won't get overshadowed in the
5413 future by other options that begin with the same letter.
5417 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5418 Many assorted bugs have been handled. Many more remain to be handled.
5419 See the various ChangeLog files (primarily in gdb and bfd) for details.
5422 *** Changes in GDB-4.3:
5424 * New machines supported (host and target)
5426 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5427 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5428 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5430 * Almost SCO Unix support
5432 We had hoped to support:
5433 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5434 (except for core file support), but we discovered very late in the release
5435 that it has problems with process groups that render gdb unusable. Sorry
5436 about that. I encourage people to fix it and post the fixes.
5438 * Preliminary ELF and DWARF support
5440 GDB can read ELF object files on System V Release 4, and can handle
5441 debugging records for C, in DWARF format, in ELF files. This support
5442 is preliminary. If you bring up GDB on another SVR4 system, please
5443 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5448 GDB now uses the latest `readline' library. One user-visible change
5449 is that two tabs will list possible command completions, which previously
5450 required typing M-? (meta-question mark, or ESC ?).
5454 The `stepi' bug that many of you noticed has been squashed.
5455 Many bugs in C++ have been handled. Many more remain to be handled.
5456 See the various ChangeLog files (primarily in gdb and bfd) for details.
5458 * State of the MIPS world (in case you wondered):
5460 GDB can understand the symbol tables emitted by the compilers
5461 supplied by most vendors of MIPS-based machines, including DEC. These
5462 symbol tables are in a format that essentially nobody else uses.
5464 Some versions of gcc come with an assembler post-processor called
5465 mips-tfile. This program is required if you want to do source-level
5466 debugging of gcc-compiled programs. I believe FSF does not ship
5467 mips-tfile with gcc version 1, but it will eventually come with gcc
5470 Debugging of g++ output remains a problem. g++ version 1.xx does not
5471 really support it at all. (If you're lucky, you should be able to get
5472 line numbers and stack traces to work, but no parameters or local
5473 variables.) With some work it should be possible to improve the
5476 When gcc version 2 is released, you will have somewhat better luck.
5477 However, even then you will get confusing results for inheritance and
5480 We will eventually provide full debugging of g++ output on
5481 DECstations. This will probably involve some kind of stabs-in-ecoff
5482 encapulation, but the details have not been worked out yet.
5485 *** Changes in GDB-4.2:
5487 * Improved configuration
5489 Only one copy of `configure' exists now, and it is not self-modifying.
5490 Porting BFD is simpler.
5494 The `step' and `next' commands now only stop at the first instruction
5495 of a source line. This prevents the multiple stops that used to occur
5496 in switch statements, for-loops, etc. `Step' continues to stop if a
5497 function that has debugging information is called within the line.
5501 Lots of small bugs fixed. More remain.
5503 * New host supported (not target)
5505 Intel 386 PC clone running Mach i386-none-mach
5508 *** Changes in GDB-4.1:
5510 * Multiple source language support
5512 GDB now has internal scaffolding to handle several source languages.
5513 It determines the type of each source file from its filename extension,
5514 and will switch expression parsing and number formatting to match the
5515 language of the function in the currently selected stack frame.
5516 You can also specifically set the language to be used, with
5517 `set language c' or `set language modula-2'.
5521 GDB now has preliminary support for the GNU Modula-2 compiler,
5522 currently under development at the State University of New York at
5523 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5524 continue through the fall of 1991 and into 1992.
5526 Other Modula-2 compilers are currently not supported, and attempting to
5527 debug programs compiled with them will likely result in an error as the
5528 symbol table is read. Feel free to work on it, though!
5530 There are hooks in GDB for strict type checking and range checking,
5531 in the `Modula-2 philosophy', but they do not currently work.
5535 GDB can now write to executable and core files (e.g. patch
5536 a variable's value). You must turn this switch on, specify
5537 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5538 by assigning a new value to a variable. Modifications take
5541 * Automatic SunOS shared library reading
5543 When you run your program, GDB automatically determines where its
5544 shared libraries (if any) have been loaded, and reads their symbols.
5545 The `share' command is no longer needed. This also works when
5546 examining core files.
5550 You can specify the number of lines that the `list' command shows.
5553 * New machines supported (host and target)
5555 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5556 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5557 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5559 * New hosts supported (not targets)
5561 IBM RT/PC: romp-ibm-aix or rtpc
5563 * New targets supported (not hosts)
5565 AMD 29000 embedded with COFF a29k-none-coff
5566 AMD 29000 embedded with a.out a29k-none-aout
5567 Ultracomputer remote kernel debug a29k-nyu-kern
5569 * New remote interfaces
5575 *** Changes in GDB-4.0:
5579 Wide output is wrapped at good places to make the output more readable.
5581 Gdb now supports cross-debugging from a host machine of one type to a
5582 target machine of another type. Communication with the target system
5583 is over serial lines. The ``target'' command handles connecting to the
5584 remote system; the ``load'' command will download a program into the
5585 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5586 also supports debugging of realtime processes running under VxWorks,
5587 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5588 stub on the target system.
5590 New CPUs supported include the AMD 29000 and Intel 960.
5592 GDB now reads object files and symbol tables via a ``binary file''
5593 library, which allows a single copy of GDB to debug programs of multiple
5594 object file types such as a.out and coff.
5596 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5597 refcard.dvi and refcard.ps are available to format it).
5600 * Control-Variable user interface simplified
5602 All variables that control the operation of the debugger can be set
5603 by the ``set'' command, and displayed by the ``show'' command.
5605 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5606 ``Show prompt'' produces the response:
5607 Gdb's prompt is new-gdb=>.
5609 What follows are the NEW set commands. The command ``help set'' will
5610 print a complete list of old and new set commands. ``help set FOO''
5611 will give a longer description of the variable FOO. ``show'' will show
5612 all of the variable descriptions and their current settings.
5614 confirm on/off: Enables warning questions for operations that are
5615 hard to recover from, e.g. rerunning the program while
5616 it is already running. Default is ON.
5618 editing on/off: Enables EMACS style command line editing
5619 of input. Previous lines can be recalled with
5620 control-P, the current line can be edited with control-B,
5621 you can search for commands with control-R, etc.
5624 history filename NAME: NAME is where the gdb command history
5625 will be stored. The default is .gdb_history,
5626 or the value of the environment variable
5629 history size N: The size, in commands, of the command history. The
5630 default is 256, or the value of the environment variable
5633 history save on/off: If this value is set to ON, the history file will
5634 be saved after exiting gdb. If set to OFF, the
5635 file will not be saved. The default is OFF.
5637 history expansion on/off: If this value is set to ON, then csh-like
5638 history expansion will be performed on
5639 command line input. The default is OFF.
5641 radix N: Sets the default radix for input and output. It can be set
5642 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5643 in the current radix, so "set radix 10" is always a no-op.
5645 height N: This integer value is the number of lines on a page. Default
5646 is 24, the current `stty rows'' setting, or the ``li#''
5647 setting from the termcap entry matching the environment
5650 width N: This integer value is the number of characters on a line.
5651 Default is 80, the current `stty cols'' setting, or the ``co#''
5652 setting from the termcap entry matching the environment
5655 Note: ``set screensize'' is obsolete. Use ``set height'' and
5656 ``set width'' instead.
5658 print address on/off: Print memory addresses in various command displays,
5659 such as stack traces and structure values. Gdb looks
5660 more ``symbolic'' if you turn this off; it looks more
5661 ``machine level'' with it on. Default is ON.
5663 print array on/off: Prettyprint arrays. New convenient format! Default
5666 print demangle on/off: Print C++ symbols in "source" form if on,
5669 print asm-demangle on/off: Same, for assembler level printouts
5672 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5675 * Support for Epoch Environment.
5677 The epoch environment is a version of Emacs v18 with windowing. One
5678 new command, ``inspect'', is identical to ``print'', except that if you
5679 are running in the epoch environment, the value is printed in its own
5683 * Support for Shared Libraries
5685 GDB can now debug programs and core files that use SunOS shared libraries.
5686 Symbols from a shared library cannot be referenced
5687 before the shared library has been linked with the program (this
5688 happens after you type ``run'' and before the function main() is entered).
5689 At any time after this linking (including when examining core files
5690 from dynamically linked programs), gdb reads the symbols from each
5691 shared library when you type the ``sharedlibrary'' command.
5692 It can be abbreviated ``share''.
5694 sharedlibrary REGEXP: Load shared object library symbols for files
5695 matching a unix regular expression. No argument
5696 indicates to load symbols for all shared libraries.
5698 info sharedlibrary: Status of loaded shared libraries.
5703 A watchpoint stops execution of a program whenever the value of an
5704 expression changes. Checking for this slows down execution
5705 tremendously whenever you are in the scope of the expression, but is
5706 quite useful for catching tough ``bit-spreader'' or pointer misuse
5707 problems. Some machines such as the 386 have hardware for doing this
5708 more quickly, and future versions of gdb will use this hardware.
5710 watch EXP: Set a watchpoint (breakpoint) for an expression.
5712 info watchpoints: Information about your watchpoints.
5714 delete N: Deletes watchpoint number N (same as breakpoints).
5715 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5716 enable N: Re-enables watchpoint number N (same as breakpoints).
5719 * C++ multiple inheritance
5721 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5724 * C++ exception handling
5726 Gdb now supports limited C++ exception handling. Besides the existing
5727 ability to breakpoint on an exception handler, gdb can breakpoint on
5728 the raising of an exception (before the stack is peeled back to the
5731 catch FOO: If there is a FOO exception handler in the dynamic scope,
5732 set a breakpoint to catch exceptions which may be raised there.
5733 Multiple exceptions (``catch foo bar baz'') may be caught.
5735 info catch: Lists all exceptions which may be caught in the
5736 current stack frame.
5739 * Minor command changes
5741 The command ``call func (arg, arg, ...)'' now acts like the print
5742 command, except it does not print or save a value if the function's result
5743 is void. This is similar to dbx usage.
5745 The ``up'' and ``down'' commands now always print the frame they end up
5746 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5747 frames without printing.
5749 * New directory command
5751 'dir' now adds directories to the FRONT of the source search path.
5752 The path starts off empty. Source files that contain debug information
5753 about the directory in which they were compiled can be found even
5754 with an empty path; Sun CC and GCC include this information. If GDB can't
5755 find your source file in the current directory, type "dir .".
5757 * Configuring GDB for compilation
5759 For normal use, type ``./configure host''. See README or gdb.texinfo
5762 GDB now handles cross debugging. If you are remotely debugging between
5763 two different machines, type ``./configure host -target=targ''.
5764 Host is the machine where GDB will run; targ is the machine
5765 where the program that you are debugging will run.
5767 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5769 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5771 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5772 $k0 - $k7 on GNU/Linux.