1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.8
6 * On resume, GDB now always passes the signal the program had stopped
7 for to the thread the signal was sent to, even if the user changed
8 threads before resuming. Previously GDB would often (but not
9 always) deliver the signal to the thread that happens to be current
12 * Conversely, the "signal" command now consistently delivers the
13 requested signal to the current thread. GDB now asks for
14 confirmation if the program had stopped for a signal and the user
15 switched threads meanwhile.
17 *** Changes in GDB 7.8
19 * New command line options
22 This is an alias for the --data-directory option.
24 * GDB supports printing and modifying of variable length automatic arrays
25 as specified in ISO C99.
27 * The ARM simulator now supports instruction level tracing
28 with or without disassembly.
32 GDB now has support for scripting using Guile. Whether this is
33 available is determined at configure time.
34 Guile version 2.0 or greater is required.
35 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
37 * New commands (for set/show, see "New options" below)
41 Invoke CODE by passing it to the Guile interpreter.
45 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
47 info auto-load guile-scripts [regexp]
48 Print the list of automatically loaded Guile scripts.
50 * The source command is now capable of sourcing Guile scripts.
51 This feature is dependent on the debugger being built with Guile support.
55 set print symbol-loading (off|brief|full)
56 show print symbol-loading
57 Control whether to print informational messages when loading symbol
58 information for a file. The default is "full", but when debugging
59 programs with large numbers of shared libraries the amount of output
62 set guile print-stack (none|message|full)
63 show guile print-stack
64 Show a stack trace when an error is encountered in a Guile script.
66 set auto-load guile-scripts (on|off)
67 show auto-load guile-scripts
68 Control auto-loading of Guile script files.
70 maint ada set ignore-descriptive-types (on|off)
71 maint ada show ignore-descriptive-types
72 Control whether the debugger should ignore descriptive types in Ada
73 programs. The default is not to ignore the descriptive types. See
74 the user manual for more details on descriptive types and the intended
77 set auto-connect-native-target
79 Control whether GDB is allowed to automatically connect to the
80 native target for the run, attach, etc. commands when not connected
81 to any target yet. See also "target native" below.
83 set record btrace replay-memory-access (read-only|read-write)
84 show record btrace replay-memory-access
85 Control what memory accesses are allowed during replay.
87 maint set target-async (on|off)
88 maint show target-async
89 This controls whether GDB targets operate in syncronous or
90 asyncronous mode. Normally the default is asyncronous, if it is
91 available; but this can be changed to more easily debug problems
92 occurring only in syncronous mode.
96 Control whether MI asynchronous mode is preferred. This supersedes
97 "set target-async" of previous GDB versions.
99 * "set target-async" is deprecated as a CLI option and is now an alias
100 for "set mi-async" (only puts MI into async mode).
102 * Background execution commands (e.g., "c&", "s&", etc.) are now
103 possible ``out of the box'' if the target supports them. Previously
104 the user would need to explicitly enable the possibility with the
105 "set target-async on" command.
107 * New features in the GDB remote stub, GDBserver
109 ** New option --debug-format=option1[,option2,...] allows one to add
110 additional text to each output. At present only timestamps
111 are supported: --debug-format=timestamps.
112 Timestamps can also be turned on with the
113 "monitor set debug-format timestamps" command from GDB.
115 * The 'record instruction-history' command now starts counting instructions
116 at one. This also affects the instruction ranges reported by the
117 'record function-call-history' command when given the /i modifier.
119 * The command 'record function-call-history' supports a new modifier '/c' to
120 indent the function names based on their call stack depth.
121 The fields for the '/i' and '/l' modifier have been reordered.
122 The source line range is now prefixed with 'at'.
123 The instruction range is now prefixed with 'inst'.
124 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
125 "record instruction-history" and "list" commands.
127 * The ranges given as arguments to the 'record function-call-history' and
128 'record instruction-history' commands are now inclusive.
130 * The btrace record target now supports the 'record goto' command.
131 For locations inside the execution trace, the back trace is computed
132 based on the information stored in the execution trace.
134 * The btrace record target supports limited reverse execution and replay.
135 The target does not record data and therefore does not allow reading
138 * The "catch syscall" command now works on s390*-linux* targets.
140 * The "compare-sections" command is no longer specific to target
141 remote. It now works with all targets.
143 * All native targets are now consistently called "native".
144 Consequently, the "target child", "target GNU", "target djgpp",
145 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
146 commands have been replaced with "target native". The QNX/NTO port
147 leaves the "procfs" target in place and adds a "native" target for
148 consistency with other ports. The impact on users should be minimal
149 as these commands previously either throwed an error, or were
150 no-ops. The target's name is visible in the output of the following
151 commands: "help target", "info target", "info files", "maint print
154 * The "target native" command now connects to the native target. This
155 can be used to launch native programs even when "set
156 auto-connect-native-target" is set to off.
158 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
160 * Support for Intel(R) AVX-512 registers on GNU/Linux.
161 Support displaying and modifying Intel(R) AVX-512 registers
162 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
166 qXfer:btrace:read's annex
167 The qXfer:btrace:read packet supports a new annex 'delta' to read
168 branch trace incrementally.
172 ** Valid Python operations on gdb.Value objects representing
173 structs/classes invoke the corresponding overloaded operators if
175 ** New `Xmethods' feature in the Python API. Xmethods are
176 additional methods or replacements for existing methods of a C++
177 class. This feature is useful for those cases where a method
178 defined in C++ source code could be inlined or optimized out by
179 the compiler, making it unavailable to GDB.
182 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
184 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
185 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
186 its alias "share", instead.
188 * The commands "set remotebaud" and "show remotebaud" are no longer
189 supported. Use "set serial baud" and "show serial baud" (respectively)
194 ** A new option "-gdb-set mi-async" replaces "-gdb-set
195 target-async". The latter is left as a deprecated alias of the
196 former for backward compatibility. If the target supports it,
197 CLI background execution commands are now always possible by
198 default, independently of whether the frontend stated a
199 preference for asynchronous execution with "-gdb-set mi-async".
200 Previously "-gdb-set target-async off" affected both MI execution
201 commands and CLI execution commands.
203 *** Changes in GDB 7.7
205 * Improved support for process record-replay and reverse debugging on
206 arm*-linux* targets. Support for thumb32 and syscall instruction
207 recording has been added.
209 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
211 * GDB now supports Fission DWP file format version 2.
212 http://gcc.gnu.org/wiki/DebugFission
214 * New convenience function "$_isvoid", to check whether an expression
215 is void. A void expression is an expression where the type of the
216 result is "void". For example, some convenience variables may be
217 "void" when evaluated (e.g., "$_exitcode" before the execution of
218 the program being debugged; or an undefined convenience variable).
219 Another example, when calling a function whose return type is
222 * The "maintenance print objfiles" command now takes an optional regexp.
224 * The "catch syscall" command now works on arm*-linux* targets.
226 * GDB now consistently shows "<not saved>" when printing values of
227 registers the debug info indicates have not been saved in the frame
228 and there's nowhere to retrieve them from
229 (callee-saved/call-clobbered registers):
234 (gdb) info registers rax
237 Before, the former would print "<optimized out>", and the latter
238 "*value not available*".
240 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
245 ** Frame filters and frame decorators have been added.
246 ** Temporary breakpoints are now supported.
247 ** Line tables representation has been added.
248 ** New attribute 'parent_type' for gdb.Field objects.
249 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
250 ** New attribute 'name' for gdb.Type objects.
254 Nios II ELF nios2*-*-elf
255 Nios II GNU/Linux nios2*-*-linux
256 Texas Instruments MSP430 msp430*-*-elf
258 * Removed native configurations
260 Support for these a.out NetBSD and OpenBSD obsolete configurations has
261 been removed. ELF variants of these configurations are kept supported.
263 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
264 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
265 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
266 i[34567]86-*-openbsd3.[0-3]
267 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
268 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
269 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
273 Like "catch throw", but catches a re-thrown exception.
275 Renamed from old "maint check-symtabs".
277 Perform consistency checks on symtabs.
279 Expand symtabs matching an optional regexp.
282 Display the details of GDB configure-time options.
284 maint set|show per-command
285 maint set|show per-command space
286 maint set|show per-command time
287 maint set|show per-command symtab
288 Enable display of per-command gdb resource usage.
290 remove-symbol-file FILENAME
291 remove-symbol-file -a ADDRESS
292 Remove a symbol file added via add-symbol-file. The file to remove
293 can be identified by its filename or by an address that lies within
294 the boundaries of this symbol file in memory.
297 info exceptions REGEXP
298 Display the list of Ada exceptions defined in the program being
299 debugged. If provided, only the exceptions whose names match REGEXP
304 set debug symfile off|on
306 Control display of debugging info regarding reading symbol files and
307 symbol tables within those files
309 set print raw frame-arguments
310 show print raw frame-arguments
311 Set/show whether to print frame arguments in raw mode,
312 disregarding any defined pretty-printers.
314 set remote trace-status-packet
315 show remote trace-status-packet
316 Set/show the use of remote protocol qTStatus packet.
320 Control display of debugging messages related to Nios II targets.
324 Control whether target-assisted range stepping is enabled.
326 set startup-with-shell
327 show startup-with-shell
328 Specifies whether Unix child processes are started via a shell or
333 Use the target memory cache for accesses to the code segment. This
334 improves performance of remote debugging (particularly disassembly).
336 * You can now use a literal value 'unlimited' for options that
337 interpret 0 or -1 as meaning "unlimited". E.g., "set
338 trace-buffer-size unlimited" is now an alias for "set
339 trace-buffer-size -1" and "set height unlimited" is now an alias for
342 * The "set debug symtab-create" debugging option of GDB has been changed to
343 accept a verbosity level. 0 means "off", 1 provides basic debugging
344 output, and values of 2 or greater provides more verbose output.
346 * New command-line options
348 Display the details of GDB configure-time options.
350 * The command 'tsave' can now support new option '-ctf' to save trace
351 buffer in Common Trace Format.
353 * Newly installed $prefix/bin/gcore acts as a shell interface for the
356 * GDB now implements the the C++ 'typeid' operator.
358 * The new convenience variable $_exception holds the exception being
359 thrown or caught at an exception-related catchpoint.
361 * The exception-related catchpoints, like "catch throw", now accept a
362 regular expression which can be used to filter exceptions by type.
364 * The new convenience variable $_exitsignal is automatically set to
365 the terminating signal number when the program being debugged dies
366 due to an uncaught signal.
370 ** All MI commands now accept an optional "--language" option.
371 Support for this feature can be verified by using the "-list-features"
372 command, which should contain "language-option".
374 ** The new command -info-gdb-mi-command allows the user to determine
375 whether a GDB/MI command is supported or not.
377 ** The "^error" result record returned when trying to execute an undefined
378 GDB/MI command now provides a variable named "code" whose content is the
379 "undefined-command" error code. Support for this feature can be verified
380 by using the "-list-features" command, which should contain
381 "undefined-command-error-code".
383 ** The -trace-save MI command can optionally save trace buffer in Common
386 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
388 ** The command -data-list-register-values now accepts an optional
389 "--skip-unavailable" option. When used, only the available registers
392 ** The new command -trace-frame-collected dumps collected variables,
393 computed expressions, tvars, memory and registers in a traceframe.
395 ** The commands -stack-list-locals, -stack-list-arguments and
396 -stack-list-variables now accept an option "--skip-unavailable".
397 When used, only the available locals or arguments are displayed.
399 ** The -exec-run command now accepts an optional "--start" option.
400 When used, the command follows the same semantics as the "start"
401 command, stopping the program's execution at the start of its
402 main subprogram. Support for this feature can be verified using
403 the "-list-features" command, which should contain
404 "exec-run-start-option".
406 ** The new commands -catch-assert and -catch-exceptions insert
407 catchpoints stopping the program when Ada exceptions are raised.
409 ** The new command -info-ada-exceptions provides the equivalent of
410 the new "info exceptions" command.
412 * New system-wide configuration scripts
413 A GDB installation now provides scripts suitable for use as system-wide
414 configuration scripts for the following systems:
418 * GDB now supports target-assigned range stepping with remote targets.
419 This improves the performance of stepping source lines by reducing
420 the number of control packets from/to GDB. See "New remote packets"
423 * GDB now understands the element 'tvar' in the XML traceframe info.
424 It has the id of the collected trace state variables.
426 * On S/390 targets that provide the transactional-execution feature,
427 the program interruption transaction diagnostic block (TDB) is now
428 represented as a number of additional "registers" in GDB.
434 The vCont packet supports a new 'r' action, that tells the remote
435 stub to step through an address range itself, without GDB
436 involvemement at each single-step.
438 qXfer:libraries-svr4:read's annex
439 The previously unused annex of the qXfer:libraries-svr4:read packet
440 is now used to support passing an argument list. The remote stub
441 reports support for this argument list to GDB's qSupported query.
442 The defined arguments are "start" and "prev", used to reduce work
443 necessary for library list updating, resulting in significant
446 * New features in the GDB remote stub, GDBserver
448 ** GDBserver now supports target-assisted range stepping. Currently
449 enabled on x86/x86_64 GNU/Linux targets.
451 ** GDBserver now adds element 'tvar' in the XML in the reply to
452 'qXfer:traceframe-info:read'. It has the id of the collected
453 trace state variables.
455 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
458 * New 'z' formatter for printing and examining memory, this displays the
459 value as hexadecimal zero padded on the left to the size of the type.
461 * GDB can now use Windows x64 unwinding data.
463 * The "set remotebaud" command has been replaced by "set serial baud".
464 Similarly, "show remotebaud" has been replaced by "show serial baud".
465 The "set remotebaud" and "show remotebaud" commands are still available
466 to provide backward compatibility with older versions of GDB.
468 *** Changes in GDB 7.6
470 * Target record has been renamed to record-full.
471 Record/replay is now enabled with the "record full" command.
472 This also affects settings that are associated with full record/replay
473 that have been moved from "set/show record" to "set/show record full":
475 set|show record full insn-number-max
476 set|show record full stop-at-limit
477 set|show record full memory-query
479 * A new record target "record-btrace" has been added. The new target
480 uses hardware support to record the control-flow of a process. It
481 does not support replaying the execution, but it implements the
482 below new commands for investigating the recorded execution log.
483 This new recording method can be enabled using:
487 The "record-btrace" target is only available on Intel Atom processors
488 and requires a Linux kernel 2.6.32 or later.
490 * Two new commands have been added for record/replay to give information
491 about the recorded execution without having to replay the execution.
492 The commands are only supported by "record btrace".
494 record instruction-history prints the execution history at
495 instruction granularity
497 record function-call-history prints the execution history at
500 * New native configurations
502 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
503 FreeBSD/powerpc powerpc*-*-freebsd
504 x86_64/Cygwin x86_64-*-cygwin*
505 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
509 ARM AArch64 aarch64*-*-elf
510 ARM AArch64 GNU/Linux aarch64*-*-linux
511 Lynx 178 PowerPC powerpc-*-lynx*178
512 x86_64/Cygwin x86_64-*-cygwin*
513 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
515 * If the configured location of system.gdbinit file (as given by the
516 --with-system-gdbinit option at configure time) is in the
517 data-directory (as specified by --with-gdb-datadir at configure
518 time) or in one of its subdirectories, then GDB will look for the
519 system-wide init file in the directory specified by the
520 --data-directory command-line option.
522 * New command line options:
524 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
525 other initialization files, unlike -nx which disables all of them.
527 * Removed command line options
529 -epoch This was used by the gdb mode in Epoch, an ancient fork of
532 * The 'ptype' and 'whatis' commands now accept an argument to control
535 * 'info proc' now works on some core files.
539 ** Vectors can be created with gdb.Type.vector.
541 ** Python's atexit.register now works in GDB.
543 ** Types can be pretty-printed via a Python API.
545 ** Python 3 is now supported (in addition to Python 2.4 or later)
547 ** New class gdb.Architecture exposes GDB's internal representation
548 of architecture in the Python API.
550 ** New method Frame.architecture returns the gdb.Architecture object
551 corresponding to the frame's architecture.
553 * New Python-based convenience functions:
555 ** $_memeq(buf1, buf2, length)
556 ** $_streq(str1, str2)
558 ** $_regex(str, regex)
560 * The 'cd' command now defaults to using '~' (the home directory) if not
563 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
564 default for GCC since November 2000.
566 * The command 'forward-search' can now be abbreviated as 'fo'.
568 * The command 'info tracepoints' can now display 'installed on target'
569 or 'not installed on target' for each non-pending location of tracepoint.
571 * New configure options
573 --enable-libmcheck/--disable-libmcheck
574 By default, development versions are built with -lmcheck on hosts
575 that support it, in order to help track memory corruption issues.
576 Release versions, on the other hand, are built without -lmcheck
577 by default. The --enable-libmcheck/--disable-libmcheck configure
578 options allow the user to override that default.
579 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
580 This configure option allows the user to build GDB with
581 libbabeltrace using which GDB can read Common Trace Format data.
583 * New commands (for set/show, see "New options" below)
586 Catch signals. This is similar to "handle", but allows commands and
587 conditions to be attached.
590 List the BFDs known to GDB.
592 python-interactive [command]
594 Start a Python interactive prompt, or evaluate the optional command
595 and print the result of expressions.
598 "py" is a new alias for "python".
600 enable type-printer [name]...
601 disable type-printer [name]...
602 Enable or disable type printers.
606 ** For the Renesas Super-H architecture, the "regs" command has been removed
607 (has been deprecated in GDB 7.5), and "info all-registers" should be used
612 set print type methods (on|off)
613 show print type methods
614 Control whether method declarations are displayed by "ptype".
615 The default is to show them.
617 set print type typedefs (on|off)
618 show print type typedefs
619 Control whether typedef definitions are displayed by "ptype".
620 The default is to show them.
622 set filename-display basename|relative|absolute
623 show filename-display
624 Control the way in which filenames is displayed.
625 The default is "relative", which preserves previous behavior.
627 set trace-buffer-size
628 show trace-buffer-size
629 Request target to change the size of trace buffer.
631 set remote trace-buffer-size-packet auto|on|off
632 show remote trace-buffer-size-packet
633 Control the use of the remote protocol `QTBuffer:size' packet.
637 Control display of debugging messages related to ARM AArch64.
640 set debug coff-pe-read
641 show debug coff-pe-read
642 Control display of debugging messages related to reading of COFF/PE
647 Control display of debugging messages related to Mach-O symbols
650 set debug notification
651 show debug notification
652 Control display of debugging info for async remote notification.
656 ** Command parameter changes are now notified using new async record
657 "=cmd-param-changed".
658 ** Trace frame changes caused by command "tfind" are now notified using
659 new async record "=traceframe-changed".
660 ** The creation, deletion and modification of trace state variables
661 are now notified using new async records "=tsv-created",
662 "=tsv-deleted" and "=tsv-modified".
663 ** The start and stop of process record are now notified using new
664 async record "=record-started" and "=record-stopped".
665 ** Memory changes are now notified using new async record
667 ** The data-disassemble command response will include a "fullname" field
668 containing the absolute file name when source has been requested.
669 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
670 command, to allow pattern filling of memory areas.
671 ** New commands "-catch-load"/"-catch-unload" added for intercepting
672 library load/unload events.
673 ** The response to breakpoint commands and breakpoint async records
674 includes an "installed" field containing a boolean state about each
675 non-pending tracepoint location is whether installed on target or not.
676 ** Output of the "-trace-status" command includes a "trace-file" field
677 containing the name of the trace file being examined. This field is
678 optional, and only present when examining a trace file.
679 ** The "fullname" field is now always present along with the "file" field,
680 even if the file cannot be found by GDB.
682 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
683 You must have the LZMA library available when configuring GDB for this
684 feature to be enabled. For more information, see:
685 http://fedoraproject.org/wiki/Features/MiniDebugInfo
690 Set the size of trace buffer. The remote stub reports support for this
691 packet to gdb's qSupported query.
694 Enable Branch Trace Store (BTS)-based branch tracing for the current
695 thread. The remote stub reports support for this packet to gdb's
699 Disable branch tracing for the current thread. The remote stub reports
700 support for this packet to gdb's qSupported query.
703 Read the traced branches for the current thread. The remote stub
704 reports support for this packet to gdb's qSupported query.
706 *** Changes in GDB 7.5
708 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
709 for more x32 ABI info.
711 * GDB now supports access to MIPS DSP registers on Linux targets.
713 * GDB now supports debugging microMIPS binaries.
715 * The "info os" command on GNU/Linux can now display information on
716 several new classes of objects managed by the operating system:
717 "info os procgroups" lists process groups
718 "info os files" lists file descriptors
719 "info os sockets" lists internet-domain sockets
720 "info os shm" lists shared-memory regions
721 "info os semaphores" lists semaphores
722 "info os msg" lists message queues
723 "info os modules" lists loaded kernel modules
725 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
726 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
727 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
728 options and inspect the probe arguments using the new $_probe_arg family
729 of convenience variables. You can obtain more information about SystemTap
730 in <http://sourceware.org/systemtap/>.
732 * GDB now supports reversible debugging on ARM, it allows you to
733 debug basic ARM and THUMB instructions, and provides
734 record/replay support.
736 * The option "symbol-reloading" has been deleted as it is no longer used.
740 ** GDB commands implemented in Python can now be put in command class
743 ** The "maint set python print-stack on|off" is now deleted.
745 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
746 apply "flag enum"-style pretty-printing to any enum.
748 ** gdb.lookup_symbol can now work when there is no current frame.
750 ** gdb.Symbol now has a 'line' attribute, holding the line number in
751 the source at which the symbol was defined.
753 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
754 method 'value'. The former indicates whether the symbol needs a
755 frame in order to compute its value, and the latter computes the
758 ** A new method 'referenced_value' on gdb.Value objects which can
759 dereference pointer as well as C++ reference values.
761 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
762 which return the global and static blocks (as gdb.Block objects),
763 of the underlying symbol table, respectively.
765 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
766 object associated with a PC value.
768 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
769 of the address range occupied by code for the current source line.
771 * Go language support.
772 GDB now supports debugging programs written in the Go programming
775 * GDBserver now supports stdio connections.
776 E.g. (gdb) target remote | ssh myhost gdbserver - hello
778 * The binary "gdbtui" can no longer be built or installed.
779 Use "gdb -tui" instead.
781 * GDB will now print "flag" enums specially. A flag enum is one where
782 all the enumerator values have no bits in common when pairwise
783 "and"ed. When printing a value whose type is a flag enum, GDB will
784 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
785 (gdb) print (enum E) 3
788 * The filename part of a linespec will now match trailing components
789 of a source file name. For example, "break gcc/expr.c:1000" will
790 now set a breakpoint in build/gcc/expr.c, but not
793 * The "info proc" and "generate-core-file" commands will now also
794 work on remote targets connected to GDBserver on Linux.
796 * The command "info catch" has been removed. It has been disabled
799 * The "catch exception" and "catch assert" commands now accept
800 a condition at the end of the command, much like the "break"
801 command does. For instance:
803 (gdb) catch exception Constraint_Error if Barrier = True
805 Previously, it was possible to add a condition to such catchpoints,
806 but it had to be done as a second step, after the catchpoint had been
807 created, using the "condition" command.
809 * The "info static-tracepoint-marker" command will now also work on
810 native Linux targets with in-process agent.
812 * GDB can now set breakpoints on inlined functions.
814 * The .gdb_index section has been updated to include symbols for
815 inlined functions. GDB will ignore older .gdb_index sections by
816 default, which could cause symbol files to be loaded more slowly
817 until their .gdb_index sections can be recreated. The new command
818 "set use-deprecated-index-sections on" will cause GDB to use any older
819 .gdb_index sections it finds. This will restore performance, but the
820 ability to set breakpoints on inlined functions will be lost in symbol
821 files with older .gdb_index sections.
823 The .gdb_index section has also been updated to record more information
824 about each symbol. This speeds up the "info variables", "info functions"
825 and "info types" commands when used with programs having the .gdb_index
826 section, as well as speeding up debugging with shared libraries using
827 the .gdb_index section.
829 * Ada support for GDB/MI Variable Objects has been added.
831 * GDB can now support 'breakpoint always-inserted mode' in 'record'
836 ** New command -info-os is the MI equivalent of "info os".
838 ** Output logs ("set logging" and related) now include MI output.
842 ** "set use-deprecated-index-sections on|off"
843 "show use-deprecated-index-sections on|off"
844 Controls the use of deprecated .gdb_index sections.
846 ** "catch load" and "catch unload" can be used to stop when a shared
847 library is loaded or unloaded, respectively.
849 ** "enable count" can be used to auto-disable a breakpoint after
852 ** "info vtbl" can be used to show the virtual method tables for
853 C++ and Java objects.
855 ** "explore" and its sub commands "explore value" and "explore type"
856 can be used to recursively explore values and types of
857 expressions. These commands are available only if GDB is
858 configured with '--with-python'.
860 ** "info auto-load" shows status of all kinds of auto-loaded files,
861 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
862 sequences of commands files, "info auto-load python-scripts"
863 shows status of auto-loading Python script files,
864 "info auto-load local-gdbinit" shows status of loading init file
865 (.gdbinit) from current directory and "info auto-load libthread-db" shows
866 status of inferior specific thread debugging shared library loading.
868 ** "info auto-load-scripts", "set auto-load-scripts on|off"
869 and "show auto-load-scripts" commands have been deprecated, use their
870 "info auto-load python-scripts", "set auto-load python-scripts on|off"
871 and "show auto-load python-scripts" counterparts instead.
873 ** "dprintf location,format,args..." creates a dynamic printf, which
874 is basically a breakpoint that does a printf and immediately
875 resumes your program's execution, so it is like a printf that you
876 can insert dynamically at runtime instead of at compiletime.
878 ** "set print symbol"
880 Controls whether GDB attempts to display the symbol, if any,
881 corresponding to addresses it prints. This defaults to "on", but
882 you can set it to "off" to restore GDB's previous behavior.
884 * Deprecated commands
886 ** For the Renesas Super-H architecture, the "regs" command has been
887 deprecated, and "info all-registers" should be used instead.
891 Renesas RL78 rl78-*-elf
892 HP OpenVMS ia64 ia64-hp-openvms*
894 * GDBserver supports evaluation of breakpoint conditions. When
895 support is advertised by GDBserver, GDB may be told to send the
896 breakpoint conditions in bytecode form to GDBserver. GDBserver
897 will only report the breakpoint trigger to GDB when its condition
903 show mips compression
904 Select the compressed ISA encoding used in functions that have no symbol
905 information available. The encoding can be set to either of:
908 and is updated automatically from ELF file flags if available.
910 set breakpoint condition-evaluation
911 show breakpoint condition-evaluation
912 Control whether breakpoint conditions are evaluated by GDB ("host") or by
913 GDBserver ("target"). Default option "auto" chooses the most efficient
915 This option can improve debugger efficiency depending on the speed of the
919 Disable auto-loading globally.
922 Show auto-loading setting of all kinds of auto-loaded files.
924 set auto-load gdb-scripts on|off
925 show auto-load gdb-scripts
926 Control auto-loading of GDB canned sequences of commands files.
928 set auto-load python-scripts on|off
929 show auto-load python-scripts
930 Control auto-loading of Python script files.
932 set auto-load local-gdbinit on|off
933 show auto-load local-gdbinit
934 Control loading of init file (.gdbinit) from current directory.
936 set auto-load libthread-db on|off
937 show auto-load libthread-db
938 Control auto-loading of inferior specific thread debugging shared library.
940 set auto-load scripts-directory <dir1>[:<dir2>...]
941 show auto-load scripts-directory
942 Set a list of directories from which to load auto-loaded scripts.
943 Automatically loaded Python scripts and GDB scripts are located in one
944 of the directories listed by this option.
945 The delimiter (':' above) may differ according to the host platform.
947 set auto-load safe-path <dir1>[:<dir2>...]
948 show auto-load safe-path
949 Set a list of directories from which it is safe to auto-load files.
950 The delimiter (':' above) may differ according to the host platform.
952 set debug auto-load on|off
954 Control display of debugging info for auto-loading the files above.
956 set dprintf-style gdb|call|agent
958 Control the way in which a dynamic printf is performed; "gdb"
959 requests a GDB printf command, while "call" causes dprintf to call a
960 function in the inferior. "agent" requests that the target agent
961 (such as GDBserver) do the printing.
963 set dprintf-function <expr>
964 show dprintf-function
965 set dprintf-channel <expr>
967 Set the function and optional first argument to the call when using
968 the "call" style of dynamic printf.
970 set disconnected-dprintf on|off
971 show disconnected-dprintf
972 Control whether agent-style dynamic printfs continue to be in effect
973 after GDB disconnects.
975 * New configure options
978 Configure default value for the 'set auto-load scripts-directory'
979 setting above. It defaults to '$debugdir:$datadir/auto-load',
980 $debugdir representing global debugging info directories (available
981 via 'show debug-file-directory') and $datadir representing GDB's data
982 directory (available via 'show data-directory').
984 --with-auto-load-safe-path
985 Configure default value for the 'set auto-load safe-path' setting
986 above. It defaults to the --with-auto-load-dir setting.
988 --without-auto-load-safe-path
989 Set 'set auto-load safe-path' to '/', effectively disabling this
994 z0/z1 conditional breakpoints extension
996 The z0/z1 breakpoint insertion packets have been extended to carry
997 a list of conditional expressions over to the remote stub depending on the
998 condition evaluation mode. The use of this extension can be controlled
999 via the "set remote conditional-breakpoints-packet" command.
1003 Specify the signals which the remote stub may pass to the debugged
1004 program without GDB involvement.
1006 * New command line options
1008 --init-command=FILE, -ix Like --command, -x but execute it
1009 before loading inferior.
1010 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
1011 execute it before loading inferior.
1013 *** Changes in GDB 7.4
1015 * GDB now handles ambiguous linespecs more consistently; the existing
1016 FILE:LINE support has been expanded to other types of linespecs. A
1017 breakpoint will now be set on all matching locations in all
1018 inferiors, and locations will be added or removed according to
1021 * GDB now allows you to skip uninteresting functions and files when
1022 stepping with the "skip function" and "skip file" commands.
1024 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1025 and "show remote hardware-watchpoint-length-limit". These allows to
1026 set or show the maximum length limit (in bytes) of a remote
1027 target hardware watchpoint.
1029 This allows e.g. to use "unlimited" hardware watchpoints with the
1030 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1031 watchpoints are slower than real hardware watchpoints but are
1032 significantly faster than gdb software watchpoints.
1036 ** The register_pretty_printer function in module gdb.printing now takes
1037 an optional `replace' argument. If True, the new printer replaces any
1040 ** The "maint set python print-stack on|off" command has been
1041 deprecated and will be deleted in GDB 7.5.
1042 A new command: "set python print-stack none|full|message" has
1043 replaced it. Additionally, the default for "print-stack" is
1044 now "message", which just prints the error message without
1047 ** A prompt substitution hook (prompt_hook) is now available to the
1050 ** A new Python module, gdb.prompt has been added to the GDB Python
1051 modules library. This module provides functionality for
1052 escape sequences in prompts (used by set/show
1053 extended-prompt). These escape sequences are replaced by their
1054 corresponding value.
1056 ** Python commands and convenience-functions located in
1057 'data-directory'/python/gdb/command and
1058 'data-directory'/python/gdb/function are now automatically loaded
1061 ** Blocks now provide four new attributes. global_block and
1062 static_block will return the global and static blocks
1063 respectively. is_static and is_global are boolean attributes
1064 that indicate if the block is one of those two types.
1066 ** Symbols now provide the "type" attribute, the type of the symbol.
1068 ** The "gdb.breakpoint" function has been deprecated in favor of
1071 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1072 of a function. This class is based on the "finish" command
1073 available in the CLI.
1075 ** Type objects for struct and union types now allow access to
1076 the fields using standard Python dictionary (mapping) methods.
1077 For example, "some_type['myfield']" now works, as does
1078 "some_type.items()".
1080 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1083 ** A new function, "deep_items" has been added to the gdb.types
1084 module in the GDB Python modules library. This function returns
1085 an iterator over the fields of a struct or union type. Unlike
1086 the standard Python "iteritems" method, it will recursively traverse
1087 any anonymous fields.
1091 ** "*stopped" events can report several new "reason"s, such as
1094 ** Breakpoint changes are now notified using new async records, like
1095 "=breakpoint-modified".
1097 ** New command -ada-task-info.
1099 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1100 $sdir specifies the default system locations of shared libraries.
1101 $pdir specifies the directory where the libpthread used by the application
1104 GDB no longer looks in $sdir and $pdir after it has searched the directories
1105 mentioned in libthread-db-search-path. If you want to search those
1106 directories, they must be specified in libthread-db-search-path.
1107 The default value of libthread-db-search-path on GNU/Linux and Solaris
1108 systems is now "$sdir:$pdir".
1110 $pdir is not supported by gdbserver, it is currently ignored.
1111 $sdir is supported by gdbserver.
1113 * New configure option --with-iconv-bin.
1114 When using the internationalization support like the one in the GNU C
1115 library, GDB will invoke the "iconv" program to get a list of supported
1116 character sets. If this program lives in a non-standard location, one can
1117 use this option to specify where to find it.
1119 * When natively debugging programs on PowerPC BookE processors running
1120 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1121 watchpoints, which specify a mask in addition to an address to watch.
1122 The mask specifies that some bits of an address (the bits which are
1123 reset in the mask) should be ignored when matching the address accessed
1124 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1125 section in the user manual for more details.
1127 * The new option --once causes GDBserver to stop listening for connections once
1128 the first connection is made. The listening port used by GDBserver will
1129 become available after that.
1131 * New commands "info macros" and "alias" have been added.
1133 * New function parameters suffix @entry specifies value of function parameter
1134 at the time the function got called. Entry values are available only since
1140 "!" is now an alias of the "shell" command.
1141 Note that no space is needed between "!" and SHELL COMMAND.
1145 watch EXPRESSION mask MASK_VALUE
1146 The watch command now supports the mask argument which allows creation
1147 of masked watchpoints, if the current architecture supports this feature.
1149 info auto-load-scripts [REGEXP]
1150 This command was formerly named "maintenance print section-scripts".
1151 It is now generally useful and is no longer a maintenance-only command.
1153 info macro [-all] [--] MACRO
1154 The info macro command has new options `-all' and `--'. The first for
1155 printing all definitions of a macro. The second for explicitly specifying
1156 the end of arguments and the beginning of the macro name in case the macro
1157 name starts with a hyphen.
1159 collect[/s] EXPRESSIONS
1160 The tracepoint collect command now takes an optional modifier "/s"
1161 that directs it to dereference pointer-to-character types and
1162 collect the bytes of memory up to a zero byte. The behavior is
1163 similar to what you see when you use the regular print command on a
1164 string. An optional integer following the "/s" sets a bound on the
1165 number of bytes that will be collected.
1168 The trace start command now interprets any supplied arguments as a
1169 note to be recorded with the trace run, with an effect similar to
1170 setting the variable trace-notes.
1173 The trace stop command now interprets any arguments as a note to be
1174 mentioned along with the tstatus report that the trace was stopped
1175 with a command. The effect is similar to setting the variable
1178 * Tracepoints can now be enabled and disabled at any time after a trace
1179 experiment has been started using the standard "enable" and "disable"
1180 commands. It is now possible to start a trace experiment with no enabled
1181 tracepoints; GDB will display a warning, but will allow the experiment to
1182 begin, assuming that tracepoints will be enabled as needed while the trace
1185 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1186 locations with 4-byte instructions, when they were previously
1187 limited to locations with instructions of 5 bytes or longer.
1191 set debug dwarf2-read
1192 show debug dwarf2-read
1193 Turns on or off display of debugging messages related to reading
1194 DWARF debug info. The default is off.
1196 set debug symtab-create
1197 show debug symtab-create
1198 Turns on or off display of debugging messages related to symbol table
1199 creation. The default is off.
1202 show extended-prompt
1203 Set the GDB prompt, and allow escape sequences to be inserted to
1204 display miscellaneous information (see 'help set extended-prompt'
1205 for the list of sequences). This prompt (and any information
1206 accessed through the escape sequences) is updated every time the
1207 prompt is displayed.
1209 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1210 show print entry-values
1211 Set printing of frame argument values at function entry. In some cases
1212 GDB can determine the value of function argument which was passed by the
1213 function caller, even if the value was modified inside the called function.
1215 set debug entry-values
1216 show debug entry-values
1217 Control display of debugging info for determining frame argument values at
1218 function entry and virtual tail call frames.
1220 set basenames-may-differ
1221 show basenames-may-differ
1222 Set whether a source file may have multiple base names.
1223 (A "base name" is the name of a file with the directory part removed.
1224 Example: The base name of "/home/user/hello.c" is "hello.c".)
1225 If set, GDB will canonicalize file names (e.g., expand symlinks)
1226 before comparing them. Canonicalization is an expensive operation,
1227 but it allows the same file be known by more than one base name.
1228 If not set (the default), all source files are assumed to have just
1229 one base name, and gdb will do file name comparisons more efficiently.
1235 Set a user name and notes for the current and any future trace runs.
1236 This is useful for long-running and/or disconnected traces, to
1237 inform others (or yourself) as to who is running the trace, supply
1238 contact information, or otherwise explain what is going on.
1240 set trace-stop-notes
1241 show trace-stop-notes
1242 Set a note attached to the trace run, that is displayed when the
1243 trace has been stopped by a tstop command. This is useful for
1244 instance as an explanation, if you are stopping a trace run that was
1245 started by someone else.
1247 * New remote packets
1251 Dynamically enable a tracepoint in a started trace experiment.
1255 Dynamically disable a tracepoint in a started trace experiment.
1259 Set the user and notes of the trace run.
1263 Query the current status of a tracepoint.
1267 Query the minimum length of instruction at which a fast tracepoint may
1270 * Dcache size (number of lines) and line-size are now runtime-configurable
1271 via "set dcache line" and "set dcache line-size" commands.
1275 Texas Instruments TMS320C6x tic6x-*-*
1279 Renesas RL78 rl78-*-elf
1281 *** Changes in GDB 7.3.1
1283 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1285 *** Changes in GDB 7.3
1287 * GDB has a new command: "thread find [REGEXP]".
1288 It finds the thread id whose name, target id, or thread extra info
1289 matches the given regular expression.
1291 * The "catch syscall" command now works on mips*-linux* targets.
1293 * The -data-disassemble MI command now supports modes 2 and 3 for
1294 dumping the instruction opcodes.
1296 * New command line options
1298 -data-directory DIR Specify DIR as the "data-directory".
1299 This is mostly for testing purposes.
1301 * The "maint set python auto-load on|off" command has been renamed to
1302 "set auto-load-scripts on|off".
1304 * GDB has a new command: "set directories".
1305 It is like the "dir" command except that it replaces the
1306 source path list instead of augmenting it.
1308 * GDB now understands thread names.
1310 On GNU/Linux, "info threads" will display the thread name as set by
1311 prctl or pthread_setname_np.
1313 There is also a new command, "thread name", which can be used to
1314 assign a name internally for GDB to display.
1317 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1318 has been integrated into GDB.
1322 ** The function gdb.Write now accepts an optional keyword 'stream'.
1323 This keyword, when provided, will direct the output to either
1324 stdout, stderr, or GDB's logging output.
1326 ** Parameters can now be be sub-classed in Python, and in particular
1327 you may implement the get_set_doc and get_show_doc functions.
1328 This improves how Parameter set/show documentation is processed
1329 and allows for more dynamic content.
1331 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1332 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1333 have an is_valid method.
1335 ** Breakpoints can now be sub-classed in Python, and in particular
1336 you may implement a 'stop' function that is executed each time
1337 the inferior reaches that breakpoint.
1339 ** New function gdb.lookup_global_symbol looks up a global symbol.
1341 ** GDB values in Python are now callable if the value represents a
1342 function. For example, if 'some_value' represents a function that
1343 takes two integer parameters and returns a value, you can call
1344 that function like so:
1346 result = some_value (10,20)
1348 ** Module gdb.types has been added.
1349 It contains a collection of utilities for working with gdb.Types objects:
1350 get_basic_type, has_field, make_enum_dict.
1352 ** Module gdb.printing has been added.
1353 It contains utilities for writing and registering pretty-printers.
1354 New classes: PrettyPrinter, SubPrettyPrinter,
1355 RegexpCollectionPrettyPrinter.
1356 New function: register_pretty_printer.
1358 ** New commands "info pretty-printers", "enable pretty-printer" and
1359 "disable pretty-printer" have been added.
1361 ** gdb.parameter("directories") is now available.
1363 ** New function gdb.newest_frame returns the newest frame in the
1366 ** The gdb.InferiorThread class has a new "name" attribute. This
1367 holds the thread's name.
1369 ** Python Support for Inferior events.
1370 Python scripts can add observers to be notified of events
1371 occurring in the process being debugged.
1372 The following events are currently supported:
1373 - gdb.events.cont Continue event.
1374 - gdb.events.exited Inferior exited event.
1375 - gdb.events.stop Signal received, and Breakpoint hit events.
1379 ** GDB now puts template parameters in scope when debugging in an
1380 instantiation. For example, if you have:
1382 template<int X> int func (void) { return X; }
1384 then if you step into func<5>, "print X" will show "5". This
1385 feature requires proper debuginfo support from the compiler; it
1386 was added to GCC 4.5.
1388 ** The motion commands "next", "finish", "until", and "advance" now
1389 work better when exceptions are thrown. In particular, GDB will
1390 no longer lose control of the inferior; instead, the GDB will
1391 stop the inferior at the point at which the exception is caught.
1392 This functionality requires a change in the exception handling
1393 code that was introduced in GCC 4.5.
1395 * GDB now follows GCC's rules on accessing volatile objects when
1396 reading or writing target state during expression evaluation.
1397 One notable difference to prior behavior is that "print x = 0"
1398 no longer generates a read of x; the value of the assignment is
1399 now always taken directly from the value being assigned.
1401 * GDB now has some support for using labels in the program's source in
1402 linespecs. For instance, you can use "advance label" to continue
1403 execution to a label.
1405 * GDB now has support for reading and writing a new .gdb_index
1406 section. This section holds a fast index of DWARF debugging
1407 information and can be used to greatly speed up GDB startup and
1408 operation. See the documentation for `save gdb-index' for details.
1410 * The "watch" command now accepts an optional "-location" argument.
1411 When used, this causes GDB to watch the memory referred to by the
1412 expression. Such a watchpoint is never deleted due to it going out
1415 * GDB now supports thread debugging of core dumps on GNU/Linux.
1417 GDB now activates thread debugging using the libthread_db library
1418 when debugging GNU/Linux core dumps, similarly to when debugging
1419 live processes. As a result, when debugging a core dump file, GDB
1420 is now able to display pthread_t ids of threads. For example, "info
1421 threads" shows the same output as when debugging the process when it
1422 was live. In earlier releases, you'd see something like this:
1425 * 1 LWP 6780 main () at main.c:10
1427 While now you see this:
1430 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1432 It is also now possible to inspect TLS variables when debugging core
1435 When debugging a core dump generated on a machine other than the one
1436 used to run GDB, you may need to point GDB at the correct
1437 libthread_db library with the "set libthread-db-search-path"
1438 command. See the user manual for more details on this command.
1440 * When natively debugging programs on PowerPC BookE processors running
1441 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1442 which stop execution of the inferior whenever it executes an instruction
1443 at any address within the specified range. See the "PowerPC Embedded"
1444 section in the user manual for more details.
1446 * New features in the GDB remote stub, GDBserver
1448 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1449 and i686 LynxOS (version 5.x).
1451 ** GDBserver is now supported on Blackfin Linux.
1453 * New native configurations
1455 ia64 HP-UX ia64-*-hpux*
1459 Analog Devices, Inc. Blackfin Processor bfin-*
1461 * Ada task switching is now supported on sparc-elf targets when
1462 debugging a program using the Ravenscar Profile. For more information,
1463 see the "Tasking Support when using the Ravenscar Profile" section
1464 in the GDB user manual.
1466 * Guile support was removed.
1468 * New features in the GNU simulator
1470 ** The --map-info flag lists all known core mappings.
1472 ** CFI flashes may be simulated via the "cfi" device.
1474 *** Changes in GDB 7.2
1476 * Shared library support for remote targets by default
1478 When GDB is configured for a generic, non-OS specific target, like
1479 for example, --target=arm-eabi or one of the many *-*-elf targets,
1480 GDB now queries remote stubs for loaded shared libraries using the
1481 `qXfer:libraries:read' packet. Previously, shared library support
1482 was always disabled for such configurations.
1486 ** Argument Dependent Lookup (ADL)
1488 In C++ ADL lookup directs function search to the namespaces of its
1489 arguments even if the namespace has not been imported.
1499 Here the compiler will search for `foo' in the namespace of 'b'
1500 and find A::foo. GDB now supports this. This construct is commonly
1501 used in the Standard Template Library for operators.
1503 ** Improved User Defined Operator Support
1505 In addition to member operators, GDB now supports lookup of operators
1506 defined in a namespace and imported with a `using' directive, operators
1507 defined in the global scope, operators imported implicitly from an
1508 anonymous namespace, and the ADL operators mentioned in the previous
1510 GDB now also supports proper overload resolution for all the previously
1511 mentioned flavors of operators.
1513 ** static const class members
1515 Printing of static const class members that are initialized in the
1516 class definition has been fixed.
1518 * Windows Thread Information Block access.
1520 On Windows targets, GDB now supports displaying the Windows Thread
1521 Information Block (TIB) structure. This structure is visible either
1522 by using the new command `info w32 thread-information-block' or, by
1523 dereferencing the new convenience variable named `$_tlb', a
1524 thread-specific pointer to the TIB. This feature is also supported
1525 when remote debugging using GDBserver.
1527 * Static tracepoints
1529 Static tracepoints are calls in the user program into a tracing
1530 library. One such library is a port of the LTTng kernel tracer to
1531 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1532 When debugging with GDBserver, GDB now supports combining the GDB
1533 tracepoint machinery with such libraries. For example: the user can
1534 use GDB to probe a static tracepoint marker (a call from the user
1535 program into the tracing library) with the new "strace" command (see
1536 "New commands" below). This creates a "static tracepoint" in the
1537 breakpoint list, that can be manipulated with the same feature set
1538 as fast and regular tracepoints. E.g., collect registers, local and
1539 global variables, collect trace state variables, and define
1540 tracepoint conditions. In addition, the user can collect extra
1541 static tracepoint marker specific data, by collecting the new
1542 $_sdata internal variable. When analyzing the trace buffer, you can
1543 inspect $_sdata like any other variable available to GDB. For more
1544 information, see the "Tracepoints" chapter in GDB user manual. New
1545 remote packets have been defined to support static tracepoints, see
1546 the "New remote packets" section below.
1548 * Better reconstruction of tracepoints after disconnected tracing
1550 GDB will attempt to download the original source form of tracepoint
1551 definitions when starting a trace run, and then will upload these
1552 upon reconnection to the target, resulting in a more accurate
1553 reconstruction of the tracepoints that are in use on the target.
1557 You can now exercise direct control over the ways that GDB can
1558 affect your program. For instance, you can disallow the setting of
1559 breakpoints, so that the program can run continuously (assuming
1560 non-stop mode). In addition, the "observer" variable is available
1561 to switch all of the different controls; in observer mode, GDB
1562 cannot affect the target's behavior at all, which is useful for
1563 tasks like diagnosing live systems in the field.
1565 * The new convenience variable $_thread holds the number of the
1568 * New remote packets
1572 Return the address of the Windows Thread Information Block of a given thread.
1576 In response to several of the tracepoint packets, the target may now
1577 also respond with a number of intermediate `qRelocInsn' request
1578 packets before the final result packet, to have GDB handle
1579 relocating an instruction to execute at a different address. This
1580 is particularly useful for stubs that support fast tracepoints. GDB
1581 reports support for this feature in the qSupported packet.
1585 List static tracepoint markers in the target program.
1589 List static tracepoint markers at a given address in the target
1592 qXfer:statictrace:read
1594 Read the static trace data collected (by a `collect $_sdata'
1595 tracepoint action). The remote stub reports support for this packet
1596 to gdb's qSupported query.
1600 Send the current settings of GDB's permission flags.
1604 Send part of the source (textual) form of a tracepoint definition,
1605 which includes location, conditional, and action list.
1607 * The source command now accepts a -s option to force searching for the
1608 script in the source search path even if the script name specifies
1611 * New features in the GDB remote stub, GDBserver
1613 - GDBserver now support tracepoints (including fast tracepoints, and
1614 static tracepoints). The feature is currently supported by the
1615 i386-linux and amd64-linux builds. See the "Tracepoints support
1616 in gdbserver" section in the manual for more information.
1618 GDBserver JIT compiles the tracepoint's conditional agent
1619 expression bytecode into native code whenever possible for low
1620 overhead dynamic tracepoints conditionals. For such tracepoints,
1621 an expression that examines program state is evaluated when the
1622 tracepoint is reached, in order to determine whether to capture
1623 trace data. If the condition is simple and false, processing the
1624 tracepoint finishes very quickly and no data is gathered.
1626 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1627 for static tracepoints support.
1629 - GDBserver now supports x86_64 Windows 64-bit debugging.
1631 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1632 it understands register description.
1634 * The --batch flag now disables pagination and queries.
1636 * X86 general purpose registers
1638 GDB now supports reading/writing byte, word and double-word x86
1639 general purpose registers directly. This means you can use, say,
1640 $ah or $ax to refer, respectively, to the byte register AH and
1641 16-bit word register AX that are actually portions of the 32-bit
1642 register EAX or 64-bit register RAX.
1644 * The `commands' command now accepts a range of breakpoints to modify.
1645 A plain `commands' following a command that creates multiple
1646 breakpoints affects all the breakpoints set by that command. This
1647 applies to breakpoints set by `rbreak', and also applies when a
1648 single `break' command creates multiple breakpoints (e.g.,
1649 breakpoints on overloaded c++ functions).
1651 * The `rbreak' command now accepts a filename specification as part of
1652 its argument, limiting the functions selected by the regex to those
1653 in the specified file.
1655 * Support for remote debugging Windows and SymbianOS shared libraries
1656 from Unix hosts has been improved. Non Windows GDB builds now can
1657 understand target reported file names that follow MS-DOS based file
1658 system semantics, such as file names that include drive letters and
1659 use the backslash character as directory separator. This makes it
1660 possible to transparently use the "set sysroot" and "set
1661 solib-search-path" on Unix hosts to point as host copies of the
1662 target's shared libraries. See the new command "set
1663 target-file-system-kind" described below, and the "Commands to
1664 specify files" section in the user manual for more information.
1668 eval template, expressions...
1669 Convert the values of one or more expressions under the control
1670 of the string template to a command line, and call it.
1672 set target-file-system-kind unix|dos-based|auto
1673 show target-file-system-kind
1674 Set or show the assumed file system kind for target reported file
1677 save breakpoints <filename>
1678 Save all current breakpoint definitions to a file suitable for use
1679 in a later debugging session. To read the saved breakpoint
1680 definitions, use the `source' command.
1682 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1685 info static-tracepoint-markers
1686 Display information about static tracepoint markers in the target.
1688 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1689 Define a static tracepoint by probing a marker at the given
1690 function, line, address, or marker ID.
1694 Enable and disable observer mode.
1696 set may-write-registers on|off
1697 set may-write-memory on|off
1698 set may-insert-breakpoints on|off
1699 set may-insert-tracepoints on|off
1700 set may-insert-fast-tracepoints on|off
1701 set may-interrupt on|off
1702 Set individual permissions for GDB effects on the target. Note that
1703 some of these settings can have undesirable or surprising
1704 consequences, particularly when changed in the middle of a session.
1705 For instance, disabling the writing of memory can prevent
1706 breakpoints from being inserted, cause single-stepping to fail, or
1707 even crash your program, if you disable after breakpoints have been
1708 inserted. However, GDB should not crash.
1710 set record memory-query on|off
1711 show record memory-query
1712 Control whether to stop the inferior if memory changes caused
1713 by an instruction cannot be recorded.
1718 The disassemble command now supports "start,+length" form of two arguments.
1722 ** GDB now provides a new directory location, called the python directory,
1723 where Python scripts written for GDB can be installed. The location
1724 of that directory is <data-directory>/python, where <data-directory>
1725 is the GDB data directory. For more details, see section `Scripting
1726 GDB using Python' in the manual.
1728 ** The GDB Python API now has access to breakpoints, symbols, symbol
1729 tables, program spaces, inferiors, threads and frame's code blocks.
1730 Additionally, GDB Parameters can now be created from the API, and
1731 manipulated via set/show in the CLI.
1733 ** New functions gdb.target_charset, gdb.target_wide_charset,
1734 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1736 ** New exception gdb.GdbError.
1738 ** Pretty-printers are now also looked up in the current program space.
1740 ** Pretty-printers can now be individually enabled and disabled.
1742 ** GDB now looks for names of Python scripts to auto-load in a
1743 special section named `.debug_gdb_scripts', in addition to looking
1744 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1746 * Tracepoint actions were unified with breakpoint commands. In particular,
1747 there are no longer differences in "info break" output for breakpoints and
1748 tracepoints and the "commands" command can be used for both tracepoints and
1749 regular breakpoints.
1753 ARM Symbian arm*-*-symbianelf*
1755 * D language support.
1756 GDB now supports debugging programs written in the D programming
1759 * GDB now supports the extended ptrace interface for PowerPC which is
1760 available since Linux kernel version 2.6.34. This automatically enables
1761 any hardware breakpoints and additional hardware watchpoints available in
1762 the processor. The old ptrace interface exposes just one hardware
1763 watchpoint and no hardware breakpoints.
1765 * GDB is now able to use the Data Value Compare (DVC) register available on
1766 embedded PowerPC processors to implement in hardware simple watchpoint
1767 conditions of the form:
1769 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1771 This works in native GDB running on Linux kernels with the extended ptrace
1772 interface mentioned above.
1774 *** Changes in GDB 7.1
1778 ** Namespace Support
1780 GDB now supports importing of namespaces in C++. This enables the
1781 user to inspect variables from imported namespaces. Support for
1782 namepace aliasing has also been added. So, if a namespace is
1783 aliased in the current scope (e.g. namepace C=A; ) the user can
1784 print variables using the alias (e.g. (gdb) print C::x).
1788 All known bugs relating to the printing of virtual base class were
1789 fixed. It is now possible to call overloaded static methods using a
1794 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1795 and reinterpret_cast<> are now handled by the C++ expression parser.
1799 Xilinx MicroBlaze microblaze-*-*
1804 Xilinx MicroBlaze microblaze
1807 * Multi-program debugging.
1809 GDB now has support for multi-program (a.k.a. multi-executable or
1810 multi-exec) debugging. This allows for debugging multiple inferiors
1811 simultaneously each running a different program under the same GDB
1812 session. See "Debugging Multiple Inferiors and Programs" in the
1813 manual for more information. This implied some user visible changes
1814 in the multi-inferior support. For example, "info inferiors" now
1815 lists inferiors that are not running yet or that have exited
1816 already. See also "New commands" and "New options" below.
1818 * New tracing features
1820 GDB's tracepoint facility now includes several new features:
1822 ** Trace state variables
1824 GDB tracepoints now include support for trace state variables, which
1825 are variables managed by the target agent during a tracing
1826 experiment. They are useful for tracepoints that trigger each
1827 other, so for instance one tracepoint can count hits in a variable,
1828 and then a second tracepoint has a condition that is true when the
1829 count reaches a particular value. Trace state variables share the
1830 $-syntax of GDB convenience variables, and can appear in both
1831 tracepoint actions and condition expressions. Use the "tvariable"
1832 command to create, and "info tvariables" to view; see "Trace State
1833 Variables" in the manual for more detail.
1837 GDB now includes an option for defining fast tracepoints, which
1838 targets may implement more efficiently, such as by installing a jump
1839 into the target agent rather than a trap instruction. The resulting
1840 speedup can be by two orders of magnitude or more, although the
1841 tradeoff is that some program locations on some target architectures
1842 might not allow fast tracepoint installation, for instance if the
1843 instruction to be replaced is shorter than the jump. To request a
1844 fast tracepoint, use the "ftrace" command, with syntax identical to
1845 the regular trace command.
1847 ** Disconnected tracing
1849 It is now possible to detach GDB from the target while it is running
1850 a trace experiment, then reconnect later to see how the experiment
1851 is going. In addition, a new variable disconnected-tracing lets you
1852 tell the target agent whether to continue running a trace if the
1853 connection is lost unexpectedly.
1857 GDB now has the ability to save the trace buffer into a file, and
1858 then use that file as a target, similarly to you can do with
1859 corefiles. You can select trace frames, print data that was
1860 collected in them, and use tstatus to display the state of the
1861 tracing run at the moment that it was saved. To create a trace
1862 file, use "tsave <filename>", and to use it, do "target tfile
1865 ** Circular trace buffer
1867 You can ask the target agent to handle the trace buffer as a
1868 circular buffer, discarding the oldest trace frames to make room for
1869 newer ones, by setting circular-trace-buffer to on. This feature may
1870 not be available for all target agents.
1875 The disassemble command, when invoked with two arguments, now requires
1876 the arguments to be comma-separated.
1879 The info variables command now displays variable definitions. Files
1880 which only declare a variable are not shown.
1883 The source command is now capable of sourcing Python scripts.
1884 This feature is dependent on the debugger being build with Python
1887 Related to this enhancement is also the introduction of a new command
1888 "set script-extension" (see below).
1890 * New commands (for set/show, see "New options" below)
1892 record save [<FILENAME>]
1893 Save a file (in core file format) containing the process record
1894 execution log for replay debugging at a later time.
1896 record restore <FILENAME>
1897 Restore the process record execution log that was saved at an
1898 earlier time, for replay debugging.
1900 add-inferior [-copies <N>] [-exec <FILENAME>]
1903 clone-inferior [-copies <N>] [ID]
1904 Make a new inferior ready to execute the same program another
1905 inferior has loaded.
1910 maint info program-spaces
1911 List the program spaces loaded into GDB.
1913 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1914 show remote interrupt-sequence
1915 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1916 as the sequence to the remote target in order to interrupt the execution.
1917 Ctrl-C is a default. Some system prefers BREAK which is high level of
1918 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1919 Magic SysRq g. It is BREAK signal and character 'g'.
1921 set remote interrupt-on-connect [on | off]
1922 show remote interrupt-on-connect
1923 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1924 remote target when gdb connects to it. This is needed when you debug
1927 set remotebreak [on | off]
1929 Deprecated. Use "set/show remote interrupt-sequence" instead.
1931 tvariable $NAME [ = EXP ]
1932 Create or modify a trace state variable.
1935 List trace state variables and their values.
1937 delete tvariable $NAME ...
1938 Delete one or more trace state variables.
1941 Evaluate the given expressions without collecting anything into the
1942 trace buffer. (Valid in tracepoint actions only.)
1944 ftrace FN / FILE:LINE / *ADDR
1945 Define a fast tracepoint at the given function, line, or address.
1947 * New expression syntax
1949 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1950 GDB now parses 0b101010 identically with 42.
1954 set follow-exec-mode new|same
1955 show follow-exec-mode
1956 Control whether GDB reuses the same inferior across an exec call or
1957 creates a new one. This is useful to be able to restart the old
1958 executable after the inferior having done an exec call.
1960 set default-collect EXPR, ...
1961 show default-collect
1962 Define a list of expressions to be collected at each tracepoint.
1963 This is a useful way to ensure essential items are not overlooked,
1964 such as registers or a critical global variable.
1966 set disconnected-tracing
1967 show disconnected-tracing
1968 If set to 1, the target is instructed to continue tracing if it
1969 loses its connection to GDB. If 0, the target is to stop tracing
1972 set circular-trace-buffer
1973 show circular-trace-buffer
1974 If set to on, the target is instructed to use a circular trace buffer
1975 and discard the oldest trace frames instead of stopping the trace due
1976 to a full trace buffer. If set to off, the trace stops when the buffer
1977 fills up. Some targets may not support this.
1979 set script-extension off|soft|strict
1980 show script-extension
1981 If set to "off", the debugger does not perform any script language
1982 recognition, and all sourced files are assumed to be GDB scripts.
1983 If set to "soft" (the default), files are sourced according to
1984 filename extension, falling back to GDB scripts if the first
1986 If set to "strict", files are sourced according to filename extension.
1988 set ada trust-PAD-over-XVS on|off
1989 show ada trust-PAD-over-XVS
1990 If off, activate a workaround against a bug in the debugging information
1991 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1992 the GCC sources for more information about the GNAT encoding and
1993 PAD types in particular). It is always safe to set this option to
1994 off, but this introduces a slight performance penalty. The default
1997 * Python API Improvements
1999 ** GDB provides the new class gdb.LazyString. This is useful in
2000 some pretty-printing cases. The new method gdb.Value.lazy_string
2001 provides a simple way to create objects of this type.
2003 ** The fields returned by gdb.Type.fields now have an
2004 `is_base_class' attribute.
2006 ** The new method gdb.Type.range returns the range of an array type.
2008 ** The new method gdb.parse_and_eval can be used to parse and
2009 evaluate an expression.
2011 * New remote packets
2014 Define a trace state variable.
2017 Get the current value of a trace state variable.
2020 Set desired tracing behavior upon disconnection.
2023 Set the trace buffer to be linear or circular.
2026 Get data about the tracepoints currently in use.
2030 Process record now works correctly with hardware watchpoints.
2032 Multiple bug fixes have been made to the mips-irix port, making it
2033 much more reliable. In particular:
2034 - Debugging threaded applications is now possible again. Previously,
2035 GDB would hang while starting the program, or while waiting for
2036 the program to stop at a breakpoint.
2037 - Attaching to a running process no longer hangs.
2038 - An error occurring while loading a core file has been fixed.
2039 - Changing the value of the PC register now works again. This fixes
2040 problems observed when using the "jump" command, or when calling
2041 a function from GDB, or even when assigning a new value to $pc.
2042 - With the "finish" and "return" commands, the return value for functions
2043 returning a small array is now correctly printed.
2044 - It is now possible to break on shared library code which gets executed
2045 during a shared library init phase (code executed while executing
2046 their .init section). Previously, the breakpoint would have no effect.
2047 - GDB is now able to backtrace through the signal handler for
2048 non-threaded programs.
2050 PIE (Position Independent Executable) programs debugging is now supported.
2051 This includes debugging execution of PIC (Position Independent Code) shared
2052 libraries although for that, it should be possible to run such libraries as an
2055 *** Changes in GDB 7.0
2057 * GDB now has an interface for JIT compilation. Applications that
2058 dynamically generate code can create symbol files in memory and register
2059 them with GDB. For users, the feature should work transparently, and
2060 for JIT developers, the interface is documented in the GDB manual in the
2061 "JIT Compilation Interface" chapter.
2063 * Tracepoints may now be conditional. The syntax is as for
2064 breakpoints; either an "if" clause appended to the "trace" command,
2065 or the "condition" command is available. GDB sends the condition to
2066 the target for evaluation using the same bytecode format as is used
2067 for tracepoint actions.
2069 * The disassemble command now supports: an optional /r modifier, print the
2070 raw instructions in hex as well as in symbolic form, and an optional /m
2071 modifier to print mixed source+assembly.
2073 * Process record and replay
2075 In a architecture environment that supports ``process record and
2076 replay'', ``process record and replay'' target can record a log of
2077 the process execution, and replay it with both forward and reverse
2080 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2081 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2082 set execution-direction {forward|reverse}, for targets that support
2085 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2086 feature is available with a native GDB running on kernel version
2089 * GDB now has support for multi-byte and wide character sets on the
2090 target. Strings whose character type is wchar_t, char16_t, or
2091 char32_t are now correctly printed. GDB supports wide- and unicode-
2092 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2093 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2094 `printf'. This feature requires iconv to work properly; if your
2095 system does not have a working iconv, GDB can use GNU libiconv. See
2096 the installation instructions for more information.
2098 * GDB now supports automatic retrieval of shared library files from
2099 remote targets. To use this feature, specify a system root that begins
2100 with the `remote:' prefix, either via the `set sysroot' command or via
2101 the `--with-sysroot' configure-time option.
2103 * "info sharedlibrary" now takes an optional regex of libraries to show,
2104 and it now reports if a shared library has no debugging information.
2106 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2107 now complete on file names.
2109 * When completing in expressions, gdb will attempt to limit
2110 completions to allowable structure or union fields, where appropriate.
2111 For instance, consider:
2113 # struct example { int f1; double f2; };
2114 # struct example variable;
2117 If the user types TAB at the end of this command line, the available
2118 completions will be "f1" and "f2".
2120 * Inlined functions are now supported. They show up in backtraces, and
2121 the "step", "next", and "finish" commands handle them automatically.
2123 * GDB now supports the token-splicing (##) and stringification (#)
2124 operators when expanding macros. It also supports variable-arity
2127 * GDB now supports inspecting extra signal information, exported by
2128 the new $_siginfo convenience variable. The feature is currently
2129 implemented on linux ARM, i386 and amd64.
2131 * GDB can now display the VFP floating point registers and NEON vector
2132 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2133 can provide these registers (requires Linux 2.6.30 or later). Remote
2134 and simulator targets may also provide them.
2136 * New remote packets
2139 Search memory for a sequence of bytes.
2142 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2143 operation over reliable transport links. Use of this packet is
2144 controlled by the `set remote noack-packet' command.
2147 Kill the process with the specified process ID. Use this in preference
2148 to `k' when multiprocess protocol extensions are supported.
2151 Obtains additional operating system information
2155 Read or write additional signal information.
2157 * Removed remote protocol undocumented extension
2159 An undocumented extension to the remote protocol's `S' stop reply
2160 packet that permited the stub to pass a process id was removed.
2161 Remote servers should use the `T' stop reply packet instead.
2163 * GDB now supports multiple function calling conventions according to the
2164 DWARF-2 DW_AT_calling_convention function attribute.
2166 * The SH target utilizes the aforementioned change to distinguish between gcc
2167 and Renesas calling convention. It also adds the new CLI commands
2168 `set/show sh calling-convention'.
2170 * GDB can now read compressed debug sections, as produced by GNU gold
2171 with the --compress-debug-sections=zlib flag.
2173 * 64-bit core files are now supported on AIX.
2175 * Thread switching is now supported on Tru64.
2177 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2178 which will be allocated using malloc later in program execution.
2180 * The qXfer:libraries:read remote procotol packet now allows passing a
2181 list of section offsets.
2183 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2184 conditions handling signals delivered during attach or thread creation
2185 have also been fixed.
2187 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2188 From the user's standpoint, all unqualified instances of True and False
2189 are treated as the standard definitions, regardless of context.
2191 * GDB now parses C++ symbol and type names more flexibly. For
2194 template<typename T> class C { };
2197 GDB will now correctly handle all of:
2199 ptype C<char const *>
2200 ptype C<char const*>
2201 ptype C<const char *>
2202 ptype C<const char*>
2204 * New features in the GDB remote stub, gdbserver
2206 - The "--wrapper" command-line argument tells gdbserver to use a
2207 wrapper program to launch programs for debugging.
2209 - On PowerPC and S/390 targets, it is now possible to use a single
2210 gdbserver executable to debug both 32-bit and 64-bit programs.
2211 (This requires gdbserver itself to be built as a 64-bit executable.)
2213 - gdbserver uses the new noack protocol mode for TCP connections to
2214 reduce communications latency, if also supported and enabled in GDB.
2216 - Support for the sparc64-linux-gnu target is now included in
2219 - The amd64-linux build of gdbserver now supports debugging both
2220 32-bit and 64-bit programs.
2222 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2223 now support hardware watchpoints, and will use them automatically
2228 GDB now has support for scripting using Python. Whether this is
2229 available is determined at configure time.
2231 New GDB commands can now be written in Python.
2233 * Ada tasking support
2235 Ada tasks can now be inspected in GDB. The following commands have
2239 Print the list of Ada tasks.
2241 Print detailed information about task number N.
2243 Print the task number of the current task.
2245 Switch the context of debugging to task number N.
2247 * Support for user-defined prefixed commands. The "define" command can
2248 add new commands to existing prefixes, e.g. "target".
2250 * Multi-inferior, multi-process debugging.
2252 GDB now has generalized support for multi-inferior debugging. See
2253 "Debugging Multiple Inferiors" in the manual for more information.
2254 Although availability still depends on target support, the command
2255 set is more uniform now. The GNU/Linux specific multi-forks support
2256 has been migrated to this new framework. This implied some user
2257 visible changes; see "New commands" and also "Removed commands"
2260 * Target descriptions can now describe the target OS ABI. See the
2261 "Target Description Format" section in the user manual for more
2264 * Target descriptions can now describe "compatible" architectures
2265 to indicate that the target can execute applications for a different
2266 architecture in addition to those for the main target architecture.
2267 See the "Target Description Format" section in the user manual for
2270 * Multi-architecture debugging.
2272 GDB now includes general supports for debugging applications on
2273 hybrid systems that use more than one single processor architecture
2274 at the same time. Each such hybrid architecture still requires
2275 specific support to be added. The only hybrid architecture supported
2276 in this version of GDB is the Cell Broadband Engine.
2278 * GDB now supports integrated debugging of Cell/B.E. applications that
2279 use both the PPU and SPU architectures. To enable support for hybrid
2280 Cell/B.E. debugging, you need to configure GDB to support both the
2281 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2282 --enable-targets configure option.
2284 * Non-stop mode debugging.
2286 For some targets, GDB now supports an optional mode of operation in
2287 which you can examine stopped threads while other threads continue
2288 to execute freely. This is referred to as non-stop mode, with the
2289 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2290 section in the user manual for more information.
2292 To be able to support remote non-stop debugging, a remote stub needs
2293 to implement the non-stop mode remote protocol extensions, as
2294 described in the "Remote Non-Stop" section of the user manual. The
2295 GDB remote stub, gdbserver, has been adjusted to support these
2296 extensions on linux targets.
2298 * New commands (for set/show, see "New options" below)
2300 catch syscall [NAME(S) | NUMBER(S)]
2301 Catch system calls. Arguments, which should be names of system
2302 calls or their numbers, mean catch only those syscalls. Without
2303 arguments, every syscall will be caught. When the inferior issues
2304 any of the specified syscalls, GDB will stop and announce the system
2305 call, both when it is called and when its call returns. This
2306 feature is currently available with a native GDB running on the
2307 Linux Kernel, under the following architectures: x86, x86_64,
2308 PowerPC and PowerPC64.
2310 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2312 Search memory for a sequence of bytes.
2314 maint set python print-stack
2315 maint show python print-stack
2316 Show a stack trace when an error is encountered in a Python script.
2319 Invoke CODE by passing it to the Python interpreter.
2324 These allow macros to be defined, undefined, and listed
2328 Show operating system information about processes.
2331 List the inferiors currently under GDB's control.
2334 Switch focus to inferior number NUM.
2337 Detach from inferior number NUM.
2340 Kill inferior number NUM.
2344 set spu stop-on-load
2345 show spu stop-on-load
2346 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2348 set spu auto-flush-cache
2349 show spu auto-flush-cache
2350 Control whether to automatically flush the software-managed cache
2351 during Cell/B.E. debugging.
2353 set sh calling-convention
2354 show sh calling-convention
2355 Control the calling convention used when calling SH target functions.
2358 show debug timestamp
2359 Control display of timestamps with GDB debugging output.
2361 set disassemble-next-line
2362 show disassemble-next-line
2363 Control display of disassembled source lines or instructions when
2366 set remote noack-packet
2367 show remote noack-packet
2368 Set/show the use of remote protocol QStartNoAckMode packet. See above
2369 under "New remote packets."
2371 set remote query-attached-packet
2372 show remote query-attached-packet
2373 Control use of remote protocol `qAttached' (query-attached) packet.
2375 set remote read-siginfo-object
2376 show remote read-siginfo-object
2377 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2380 set remote write-siginfo-object
2381 show remote write-siginfo-object
2382 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2385 set remote reverse-continue
2386 show remote reverse-continue
2387 Control use of remote protocol 'bc' (reverse-continue) packet.
2389 set remote reverse-step
2390 show remote reverse-step
2391 Control use of remote protocol 'bs' (reverse-step) packet.
2393 set displaced-stepping
2394 show displaced-stepping
2395 Control displaced stepping mode. Displaced stepping is a way to
2396 single-step over breakpoints without removing them from the debuggee.
2397 Also known as "out-of-line single-stepping".
2400 show debug displaced
2401 Control display of debugging info for displaced stepping.
2403 maint set internal-error
2404 maint show internal-error
2405 Control what GDB does when an internal error is detected.
2407 maint set internal-warning
2408 maint show internal-warning
2409 Control what GDB does when an internal warning is detected.
2414 Use a wrapper program to launch programs for debugging.
2416 set multiple-symbols (all|ask|cancel)
2417 show multiple-symbols
2418 The value of this variable can be changed to adjust the debugger behavior
2419 when an expression or a breakpoint location contains an ambiguous symbol
2420 name (an overloaded function name, for instance).
2422 set breakpoint always-inserted
2423 show breakpoint always-inserted
2424 Keep breakpoints always inserted in the target, as opposed to inserting
2425 them when resuming the target, and removing them when the target stops.
2426 This option can improve debugger performance on slow remote targets.
2428 set arm fallback-mode (arm|thumb|auto)
2429 show arm fallback-mode
2430 set arm force-mode (arm|thumb|auto)
2432 These commands control how ARM GDB determines whether instructions
2433 are ARM or Thumb. The default for both settings is auto, which uses
2434 the current CPSR value for instructions without symbols; previous
2435 versions of GDB behaved as if "set arm fallback-mode arm".
2437 set disable-randomization
2438 show disable-randomization
2439 Standalone programs run with the virtual address space randomization enabled
2440 by default on some platforms. This option keeps the addresses stable across
2441 multiple debugging sessions.
2445 Control whether other threads are stopped or not when some thread hits
2450 Requests that asynchronous execution is enabled in the target, if available.
2451 In this case, it's possible to resume target in the background, and interact
2452 with GDB while the target is running. "show target-async" displays the
2453 current state of asynchronous execution of the target.
2455 set target-wide-charset
2456 show target-wide-charset
2457 The target-wide-charset is the name of the character set that GDB
2458 uses when printing characters whose type is wchar_t.
2460 set tcp auto-retry (on|off)
2462 set tcp connect-timeout
2463 show tcp connect-timeout
2464 These commands allow GDB to retry failed TCP connections to a remote stub
2465 with a specified timeout period; this is useful if the stub is launched
2466 in parallel with GDB but may not be ready to accept connections immediately.
2468 set libthread-db-search-path
2469 show libthread-db-search-path
2470 Control list of directories which GDB will search for appropriate
2473 set schedule-multiple (on|off)
2474 show schedule-multiple
2475 Allow GDB to resume all threads of all processes or only threads of
2476 the current process.
2480 Use more aggressive caching for accesses to the stack. This improves
2481 performance of remote debugging (particularly backtraces) without
2482 affecting correctness.
2484 set interactive-mode (on|off|auto)
2485 show interactive-mode
2486 Control whether GDB runs in interactive mode (on) or not (off).
2487 When in interactive mode, GDB waits for the user to answer all
2488 queries. Otherwise, GDB does not wait and assumes the default
2489 answer. When set to auto (the default), GDB determines which
2490 mode to use based on the stdin settings.
2495 For program forks, this is replaced by the new more generic `info
2496 inferiors' command. To list checkpoints, you can still use the
2497 `info checkpoints' command, which was an alias for the `info forks'
2501 Replaced by the new `inferior' command. To switch between
2502 checkpoints, you can still use the `restart' command, which was an
2503 alias for the `fork' command.
2506 This is removed, since some targets don't have a notion of
2507 processes. To switch between processes, you can still use the
2508 `inferior' command using GDB's own inferior number.
2511 For program forks, this is replaced by the new more generic `kill
2512 inferior' command. To delete a checkpoint, you can still use the
2513 `delete checkpoint' command, which was an alias for the `delete
2517 For program forks, this is replaced by the new more generic `detach
2518 inferior' command. To detach a checkpoint, you can still use the
2519 `detach checkpoint' command, which was an alias for the `detach
2522 * New native configurations
2524 x86/x86_64 Darwin i[34567]86-*-darwin*
2526 x86_64 MinGW x86_64-*-mingw*
2530 Lattice Mico32 lm32-*
2531 x86 DICOS i[34567]86-*-dicos*
2532 x86_64 DICOS x86_64-*-dicos*
2535 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2536 (mingw32ce) debugging.
2542 These commands were actually not implemented on any target.
2544 *** Changes in GDB 6.8
2546 * New native configurations
2548 NetBSD/hppa hppa*-*netbsd*
2549 Xtensa GNU/Linux xtensa*-*-linux*
2553 NetBSD/hppa hppa*-*-netbsd*
2554 Xtensa GNU/Lunux xtensa*-*-linux*
2556 * Change in command line behavior -- corefiles vs. process ids.
2558 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2559 attaching to process NUMBER fails, GDB no longer attempts to open a
2560 core file named NUMBER. Attaching to a program using the -c option
2561 is no longer supported. Instead, use the '-p' or '--pid' options.
2563 * GDB can now be built as a native debugger for debugging Windows x86
2564 (mingw32) Portable Executable (PE) programs.
2566 * Pending breakpoints no longer change their number when their address
2569 * GDB now supports breakpoints with multiple locations,
2570 including breakpoints on C++ constructors, inside C++ templates,
2571 and in inlined functions.
2573 * GDB's ability to debug optimized code has been improved. GDB more
2574 accurately identifies function bodies and lexical blocks that occupy
2575 more than one contiguous range of addresses.
2577 * Target descriptions can now describe registers for PowerPC.
2579 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2580 registers on PowerPC targets.
2582 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2583 targets even when the libthread_db library is not available.
2585 * The GDB remote stub, gdbserver, now supports the new file transfer
2586 commands (remote put, remote get, and remote delete).
2588 * The GDB remote stub, gdbserver, now supports run and attach in
2589 extended-remote mode.
2591 * hppa*64*-*-hpux11* target broken
2592 The debugger is unable to start a program and fails with the following
2593 error: "Error trying to get information about dynamic linker".
2594 The gdb-6.7 release is also affected.
2596 * GDB now supports the --enable-targets= configure option to allow
2597 building a single GDB executable that supports multiple remote
2598 target architectures.
2600 * GDB now supports debugging C and C++ programs which use the
2601 Decimal Floating Point extension. In addition, the PowerPC target
2602 now has a set of pseudo-registers to inspect decimal float values
2603 stored in two consecutive float registers.
2605 * The -break-insert MI command can optionally create pending
2608 * Improved support for debugging Ada
2609 Many improvements to the Ada language support have been made. These
2611 - Better support for Ada2005 interface types
2612 - Improved handling of arrays and slices in general
2613 - Better support for Taft-amendment types
2614 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2616 - Improved command completion in Ada
2619 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2624 set print frame-arguments (all|scalars|none)
2625 show print frame-arguments
2626 The value of this variable can be changed to control which argument
2627 values should be printed by the debugger when displaying a frame.
2632 Transfer files to and from a remote target, and delete remote files.
2639 Transfer files to and from a remote target, and delete remote files.
2641 * New remote packets
2648 Open, close, read, write, and delete files on the remote system.
2651 Attach to an existing process on the remote system, in extended-remote
2655 Run a new process on the remote system, in extended-remote mode.
2657 *** Changes in GDB 6.7
2659 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2660 bfd, libiberty and opcodes, as revealed by static analysis donated by
2661 Coverity, Inc. (http://scan.coverity.com).
2663 * When looking up multiply-defined global symbols, GDB will now prefer the
2664 symbol definition in the current shared library if it was built using the
2665 -Bsymbolic linker option.
2667 * When the Text User Interface (TUI) is not configured, GDB will now
2668 recognize the -tui command-line option and print a message that the TUI
2671 * The GDB remote stub, gdbserver, now has lower overhead for high
2672 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2674 * GDB for MIPS targets now autodetects whether a remote target provides
2675 32-bit or 64-bit register values.
2677 * Support for C++ member pointers has been improved.
2679 * GDB now understands XML target descriptions, which specify the
2680 target's overall architecture. GDB can read a description from
2681 a local file or over the remote serial protocol.
2683 * Vectors of single-byte data use a new integer type which is not
2684 automatically displayed as character or string data.
2686 * The /s format now works with the print command. It displays
2687 arrays of single-byte integers and pointers to single-byte integers
2690 * Target descriptions can now describe target-specific registers,
2691 for architectures which have implemented the support (currently
2692 only ARM, M68K, and MIPS).
2694 * GDB and the GDB remote stub, gdbserver, now support the XScale
2697 * The GDB remote stub, gdbserver, has been updated to support
2698 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2699 has been rewritten to use the standard GDB remote protocol.
2701 * GDB can now step into C++ functions which are called through thunks.
2703 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2705 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2706 layout. It also supports a TextSeg= and DataSeg= response when only
2707 segment base addresses (rather than offsets) are available.
2709 * The /i format now outputs any trailing branch delay slot instructions
2710 immediately following the last instruction within the count specified.
2712 * The GDB remote protocol "T" stop reply packet now supports a
2713 "library" response. Combined with the new "qXfer:libraries:read"
2714 packet, this response allows GDB to debug shared libraries on targets
2715 where the operating system manages the list of loaded libraries (e.g.
2716 Windows and SymbianOS).
2718 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2719 (DLLs) on Windows and Windows CE targets.
2721 * GDB now supports a faster verification that a .debug file matches its binary
2722 according to its build-id signature, if the signature is present.
2728 Enable or disable hardware flow control (RTS/CTS) on the serial port
2729 when debugging using remote targets.
2731 set mem inaccessible-by-default
2732 show mem inaccessible-by-default
2733 If the target supplies a memory map, for instance via the remote
2734 protocol's "qXfer:memory-map:read" packet, setting this variable
2735 prevents GDB from accessing memory outside the memory map. This
2736 is useful for targets with memory mapped registers or which react
2737 badly to accesses of unmapped address space.
2739 set breakpoint auto-hw
2740 show breakpoint auto-hw
2741 If the target supplies a memory map, for instance via the remote
2742 protocol's "qXfer:memory-map:read" packet, setting this variable
2743 lets GDB use hardware breakpoints automatically for memory regions
2744 where it can not use software breakpoints. This covers both the
2745 "break" command and internal breakpoints used for other commands
2746 including "next" and "finish".
2749 catch exception unhandled
2750 Stop the program execution when Ada exceptions are raised.
2753 Stop the program execution when an Ada assertion failed.
2757 Set an alternate system root for target files. This is a more
2758 general version of "set solib-absolute-prefix", which is now
2759 an alias to "set sysroot".
2762 Provide extended SPU facility status information. This set of
2763 commands is available only when debugging the Cell/B.E. SPU
2766 * New native configurations
2768 OpenBSD/sh sh*-*openbsd*
2771 unset tdesc filename
2773 Use the specified local file as an XML target description, and do
2774 not query the target for its built-in description.
2778 OpenBSD/sh sh*-*-openbsd*
2779 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2780 Toshiba Media Processor mep-elf
2782 * New remote packets
2785 Ignore the specified signals; pass them directly to the debugged program
2786 without stopping other threads or reporting them to GDB.
2788 qXfer:features:read:
2789 Read an XML target description from the target, which describes its
2794 Read or write contents of an spufs file on the target system. These
2795 packets are available only on the Cell/B.E. SPU architecture.
2797 qXfer:libraries:read:
2798 Report the loaded shared libraries. Combined with new "T" packet
2799 response, this packet allows GDB to debug shared libraries on
2800 targets where the operating system manages the list of loaded
2801 libraries (e.g. Windows and SymbianOS).
2805 Support for these obsolete configurations has been removed.
2813 i[34567]86-*-lynxos*
2814 i[34567]86-*-netware*
2815 i[34567]86-*-sco3.2v5*
2816 i[34567]86-*-sco3.2v4*
2818 i[34567]86-*-sysv4.2*
2821 i[34567]86-*-unixware2*
2822 i[34567]86-*-unixware*
2831 * Other removed features
2838 Various m68k-only ROM monitors.
2845 Various Renesas ROM monitors and debugging interfaces for SH and
2850 Support for a Macraigor serial interface to on-chip debugging.
2851 GDB does not directly support the newer parallel or USB
2856 A debug information format. The predecessor to DWARF 2 and
2857 DWARF 3, which are still supported.
2859 Support for the HP aCC compiler on HP-UX/PA-RISC
2861 SOM-encapsulated symbolic debugging information, automatic
2862 invocation of pxdb, and the aCC custom C++ ABI. This does not
2863 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2864 with aCC can still be debugged on an assembly level.
2866 MIPS ".pdr" sections
2868 A MIPS-specific format used to describe stack frame layout
2869 in debugging information.
2873 GDB could work with an older version of Guile to debug
2874 the interpreter and Scheme programs running in it.
2876 set mips stack-arg-size
2877 set mips saved-gpreg-size
2879 Use "set mips abi" to control parameter passing for MIPS.
2881 *** Changes in GDB 6.6
2886 Cell Broadband Engine SPU spu-elf
2888 * GDB can now be configured as a cross-debugger targeting native Windows
2889 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2890 running on a Windows system over TCP/IP to debug Windows programs.
2892 * The GDB remote stub, gdbserver, has been updated to support Windows and
2893 Cygwin debugging. Both single-threaded and multi-threaded programs are
2896 * The "set trust-readonly-sections" command works again. This command was
2897 broken in GDB 6.3, 6.4, and 6.5.
2899 * The "load" command now supports writing to flash memory, if the remote
2900 stub provides the required support.
2902 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2903 longer requires symbolic debug information (e.g. DWARF-2).
2908 unset substitute-path
2909 show substitute-path
2910 Manage a list of substitution rules that GDB uses to rewrite the name
2911 of the directories where the sources are located. This can be useful
2912 for instance when the sources were moved to a different location
2913 between compilation and debugging.
2917 Print each CLI command as it is executed. Each command is prefixed with
2918 a number of `+' symbols representing the nesting depth.
2919 The source command now has a `-v' option to enable the same feature.
2923 The ARM Demon monitor support (RDP protocol, "target rdp").
2925 Kernel Object Display, an embedded debugging feature which only worked with
2926 an obsolete version of Cisco IOS.
2928 The 'set download-write-size' and 'show download-write-size' commands.
2930 * New remote packets
2933 Tell a stub about GDB client features, and request remote target features.
2934 The first feature implemented is PacketSize, which allows the target to
2935 specify the size of packets it can handle - to minimize the number of
2936 packets required and improve performance when connected to a remote
2940 Fetch an OS auxilliary vector from the remote stub. This packet is a
2941 more efficient replacement for qPart:auxv:read.
2943 qXfer:memory-map:read:
2944 Fetch a memory map from the remote stub, including information about
2945 RAM, ROM, and flash memory devices.
2950 Erase and program a flash memory device.
2952 * Removed remote packets
2955 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2956 used it, and only gdbserver implemented it.
2958 *** Changes in GDB 6.5
2962 Renesas M32C/M16C m32c-elf
2964 Morpho Technologies ms1 ms1-elf
2968 init-if-undefined Initialize a convenience variable, but
2969 only if it doesn't already have a value.
2971 The following commands are presently only implemented for native GNU/Linux:
2973 checkpoint Save a snapshot of the program state.
2975 restart <n> Return the program state to a
2976 previously saved state.
2978 info checkpoints List currently saved checkpoints.
2980 delete-checkpoint <n> Delete a previously saved checkpoint.
2982 set|show detach-on-fork Tell gdb whether to detach from a newly
2983 forked process, or to keep debugging it.
2985 info forks List forks of the user program that
2986 are available to be debugged.
2988 fork <n> Switch to debugging one of several
2989 forks of the user program that are
2990 available to be debugged.
2992 delete-fork <n> Delete a fork from the list of forks
2993 that are available to be debugged (and
2994 kill the forked process).
2996 detach-fork <n> Delete a fork from the list of forks
2997 that are available to be debugged (and
2998 allow the process to continue).
3002 Morpho Technologies ms2 ms1-elf
3004 * Improved Windows host support
3006 GDB now builds as a cross debugger hosted on i686-mingw32, including
3007 native console support, and remote communications using either
3008 network sockets or serial ports.
3010 * Improved Modula-2 language support
3012 GDB can now print most types in the Modula-2 syntax. This includes:
3013 basic types, set types, record types, enumerated types, range types,
3014 pointer types and ARRAY types. Procedure var parameters are correctly
3015 printed and hexadecimal addresses and character constants are also
3016 written in the Modula-2 syntax. Best results can be obtained by using
3017 GNU Modula-2 together with the -gdwarf-2 command line option.
3021 The ARM rdi-share module.
3023 The Netware NLM debug server.
3025 *** Changes in GDB 6.4
3027 * New native configurations
3029 OpenBSD/arm arm*-*-openbsd*
3030 OpenBSD/mips64 mips64-*-openbsd*
3034 Morpho Technologies ms1 ms1-elf
3036 * New command line options
3038 --batch-silent As for --batch, but totally silent.
3039 --return-child-result The debugger will exist with the same value
3040 the child (debugged) program exited with.
3041 --eval-command COMMAND, -ex COMMAND
3042 Execute a single GDB CLI command. This may be
3043 specified multiple times and in conjunction
3044 with the --command (-x) option.
3046 * Deprecated commands removed
3048 The following commands, that were deprecated in 2000, have been
3052 set|show arm disassembly-flavor set|show arm disassembler
3053 othernames set arm disassembler
3054 set|show remotedebug set|show debug remote
3055 set|show archdebug set|show debug arch
3056 set|show eventdebug set|show debug event
3059 * New BSD user-level threads support
3061 It is now possible to debug programs using the user-level threads
3062 library on OpenBSD and FreeBSD. Currently supported (target)
3065 FreeBSD/amd64 x86_64-*-freebsd*
3066 FreeBSD/i386 i386-*-freebsd*
3067 OpenBSD/i386 i386-*-openbsd*
3069 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3070 are not yet supported.
3072 * New support for Matsushita MN10300 w/sim added
3073 (Work in progress). mn10300-elf.
3075 * REMOVED configurations and files
3077 VxWorks and the XDR protocol *-*-vxworks
3078 Motorola MCORE mcore-*-*
3079 National Semiconductor NS32000 ns32k-*-*
3081 * New "set print array-indexes" command
3083 After turning this setting "on", GDB prints the index of each element
3084 when displaying arrays. The default is "off" to preserve the previous
3087 * VAX floating point support
3089 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3091 * User-defined command support
3093 In addition to using $arg0..$arg9 for argument passing, it is now possible
3094 to use $argc to determine now many arguments have been passed. See the
3095 section on user-defined commands in the user manual for more information.
3097 *** Changes in GDB 6.3:
3099 * New command line option
3101 GDB now accepts -l followed by a number to set the timeout for remote
3104 * GDB works with GCC -feliminate-dwarf2-dups
3106 GDB now supports a more compact representation of DWARF-2 debug
3107 information using DW_FORM_ref_addr references. These are produced
3108 by GCC with the option -feliminate-dwarf2-dups and also by some
3109 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3110 to use -feliminate-dwarf2-dups.
3112 * Internationalization
3114 When supported by the host system, GDB will be built with
3115 internationalization (libintl). The task of marking up the sources is
3116 continued, we're looking forward to our first translation.
3120 Initial support for debugging programs compiled with the GNAT
3121 implementation of the Ada programming language has been integrated
3122 into GDB. In this release, support is limited to expression evaluation.
3124 * New native configurations
3126 GNU/Linux/m32r m32r-*-linux-gnu
3130 GDB's remote protocol now includes support for the 'p' packet. This
3131 packet is used to fetch individual registers from a remote inferior.
3133 * END-OF-LIFE registers[] compatibility module
3135 GDB's internal register infrastructure has been completely rewritten.
3136 The new infrastructure making possible the implementation of key new
3137 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3140 GDB 6.3 will be the last release to include the the registers[]
3141 compatibility module that allowed out-of-date configurations to
3142 continue to work. This change directly impacts the following
3152 powerpc bdm protocol
3154 Unless there is activity to revive these configurations, they will be
3155 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3157 * OBSOLETE configurations and files
3159 Configurations that have been declared obsolete in this release have
3160 been commented out. Unless there is activity to revive these
3161 configurations, the next release of GDB will have their sources
3162 permanently REMOVED.
3171 *** Changes in GDB 6.2.1:
3173 * MIPS `break main; run' gave an heuristic-fence-post warning
3175 When attempting to run even a simple program, a warning about
3176 heuristic-fence-post being hit would be reported. This problem has
3179 * MIPS IRIX 'long double' crashed GDB
3181 When examining a long double variable, GDB would get a segmentation
3182 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3183 IRIX long double values).
3187 A bug in the VAX stack code was causing problems with the "next"
3188 command. This problem has been fixed.
3190 *** Changes in GDB 6.2:
3192 * Fix for ``many threads''
3194 On GNU/Linux systems that use the NPTL threads library, a program
3195 rapidly creating and deleting threads would confuse GDB leading to the
3198 ptrace: No such process.
3199 thread_db_get_info: cannot get thread info: generic error
3201 This problem has been fixed.
3203 * "-async" and "-noasync" options removed.
3205 Support for the broken "-noasync" option has been removed (it caused
3208 * New ``start'' command.
3210 This command runs the program until the begining of the main procedure.
3212 * New BSD Kernel Data Access Library (libkvm) interface
3214 Using ``target kvm'' it is now possible to debug kernel core dumps and
3215 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3216 platforms. Currently supported (native-only) configurations are:
3218 FreeBSD/amd64 x86_64-*-freebsd*
3219 FreeBSD/i386 i?86-*-freebsd*
3220 NetBSD/i386 i?86-*-netbsd*
3221 NetBSD/m68k m68*-*-netbsd*
3222 NetBSD/sparc sparc-*-netbsd*
3223 OpenBSD/amd64 x86_64-*-openbsd*
3224 OpenBSD/i386 i?86-*-openbsd*
3225 OpenBSD/m68k m68*-openbsd*
3226 OpenBSD/sparc sparc-*-openbsd*
3228 * Signal trampoline code overhauled
3230 Many generic problems with GDB's signal handling code have been fixed.
3231 These include: backtraces through non-contiguous stacks; recognition
3232 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3233 call; backtrace through a signal trampoline; step into and out of
3234 signal handlers; and single-stepping in the signal trampoline.
3236 Please note that kernel bugs are a limiting factor here. These
3237 features have been shown to work on an s390 GNU/Linux system that
3238 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3240 * Cygwin support for DWARF 2 added.
3242 * New native configurations
3244 GNU/Linux/hppa hppa*-*-linux*
3245 OpenBSD/hppa hppa*-*-openbsd*
3246 OpenBSD/m68k m68*-*-openbsd*
3247 OpenBSD/m88k m88*-*-openbsd*
3248 OpenBSD/powerpc powerpc-*-openbsd*
3249 NetBSD/vax vax-*-netbsd*
3250 OpenBSD/vax vax-*-openbsd*
3252 * END-OF-LIFE frame compatibility module
3254 GDB's internal frame infrastructure has been completely rewritten.
3255 The new infrastructure making it possible to support key new features
3256 including DWARF 2 Call Frame Information. To aid in the task of
3257 migrating old configurations to this new infrastructure, a
3258 compatibility module, that allowed old configurations to continue to
3259 work, was also included.
3261 GDB 6.2 will be the last release to include this frame compatibility
3262 module. This change directly impacts the following configurations:
3272 Unless there is activity to revive these configurations, they will be
3273 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3275 * REMOVED configurations and files
3277 Sun 3, running SunOS 3 m68*-*-sunos3*
3278 Sun 3, running SunOS 4 m68*-*-sunos4*
3279 Sun 2, running SunOS 3 m68000-*-sunos3*
3280 Sun 2, running SunOS 4 m68000-*-sunos4*
3281 Motorola 680x0 running LynxOS m68*-*-lynxos*
3282 AT&T 3b1/Unix pc m68*-att-*
3283 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3284 decstation mips-dec-* mips-little-*
3285 riscos mips-*-riscos* mips-*-sysv*
3286 sonymips mips-sony-*
3287 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3289 *** Changes in GDB 6.1.1:
3291 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3293 The TUI (Text-mode User Interface) is now built as part of a default
3294 GDB configuration. It is enabled by either selecting the TUI with the
3295 command line option "-i=tui" or by running the separate "gdbtui"
3296 program. For more information on the TUI, see the manual "Debugging
3299 * Pending breakpoint support (also included in GDB 6.1)
3301 Support has been added to allow you to specify breakpoints in shared
3302 libraries that have not yet been loaded. If a breakpoint location
3303 cannot be found, and the "breakpoint pending" option is set to auto,
3304 GDB queries you if you wish to make the breakpoint pending on a future
3305 shared-library load. If and when GDB resolves the breakpoint symbol,
3306 the pending breakpoint is removed as one or more regular breakpoints
3309 Pending breakpoints are very useful for GCJ Java debugging.
3311 * Fixed ISO-C build problems
3313 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3314 non ISO-C code that stopped them being built using a more strict ISO-C
3315 compiler (e.g., IBM's C compiler).
3317 * Fixed build problem on IRIX 5
3319 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3320 wasn't able to compile compile on an IRIX 5 system.
3322 * Added execute permission to gdb/gdbserver/configure
3324 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3325 permission. This bug would cause configure to fail on a number of
3326 systems (Solaris, IRIX). Ref: server/519.
3328 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3330 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3331 has been updated to use constant array sizes.
3333 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3335 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3336 its generated DWARF Call Frame Info. This encoding was causing GDB to
3337 panic, that panic has been fixed. Ref: gdb/1628.
3339 * Fixed a problem when examining parameters in shared library code.
3341 When examining parameters in optimized shared library code generated
3342 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3343 not available''. GDB now correctly displays the variable's value.
3345 *** Changes in GDB 6.1:
3347 * Removed --with-mmalloc
3349 Support for the mmalloc memory manager has been removed, as it
3350 conflicted with the internal gdb byte cache.
3352 * Changes in AMD64 configurations
3354 The AMD64 target now includes the %cs and %ss registers. As a result
3355 the AMD64 remote protocol has changed; this affects the floating-point
3356 and SSE registers. If you rely on those registers for your debugging,
3357 you should upgrade gdbserver on the remote side.
3359 * Revised SPARC target
3361 The SPARC target has been completely revised, incorporating the
3362 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3363 support for LynxOS and SunOS 4 has been dropped. Calling functions
3364 from within GDB on operating systems with a non-executable stack
3365 (Solaris, OpenBSD) now works.
3369 GDB has a new C++ demangler which does a better job on the mangled
3370 names generated by current versions of g++. It also runs faster, so
3371 with this and other changes gdb should now start faster on large C++
3374 * DWARF 2 Location Expressions
3376 GDB support for location expressions has been extended to support function
3377 arguments and frame bases. Older versions of GDB could crash when they
3380 * C++ nested types and namespaces
3382 GDB's support for nested types and namespaces in C++ has been
3383 improved, especially if you use the DWARF 2 debugging format. (This
3384 is the default for recent versions of GCC on most platforms.)
3385 Specifically, if you have a class "Inner" defined within a class or
3386 namespace "Outer", then GDB realizes that the class's name is
3387 "Outer::Inner", not simply "Inner". This should greatly reduce the
3388 frequency of complaints about not finding RTTI symbols. In addition,
3389 if you are stopped at inside of a function defined within a namespace,
3390 GDB modifies its name lookup accordingly.
3392 * New native configurations
3394 NetBSD/amd64 x86_64-*-netbsd*
3395 OpenBSD/amd64 x86_64-*-openbsd*
3396 OpenBSD/alpha alpha*-*-openbsd*
3397 OpenBSD/sparc sparc-*-openbsd*
3398 OpenBSD/sparc64 sparc64-*-openbsd*
3400 * New debugging protocols
3402 M32R with SDI protocol m32r-*-elf*
3404 * "set prompt-escape-char" command deleted.
3406 The command "set prompt-escape-char" has been deleted. This command,
3407 and its very obscure effet on GDB's prompt, was never documented,
3408 tested, nor mentioned in the NEWS file.
3410 * OBSOLETE configurations and files
3412 Configurations that have been declared obsolete in this release have
3413 been commented out. Unless there is activity to revive these
3414 configurations, the next release of GDB will have their sources
3415 permanently REMOVED.
3417 Sun 3, running SunOS 3 m68*-*-sunos3*
3418 Sun 3, running SunOS 4 m68*-*-sunos4*
3419 Sun 2, running SunOS 3 m68000-*-sunos3*
3420 Sun 2, running SunOS 4 m68000-*-sunos4*
3421 Motorola 680x0 running LynxOS m68*-*-lynxos*
3422 AT&T 3b1/Unix pc m68*-att-*
3423 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3424 decstation mips-dec-* mips-little-*
3425 riscos mips-*-riscos* mips-*-sysv*
3426 sonymips mips-sony-*
3427 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3429 * REMOVED configurations and files
3431 SGI Irix-4.x mips-sgi-irix4 or iris4
3432 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3433 Z8000 simulator z8k-zilog-none or z8ksim
3434 Matsushita MN10200 w/simulator mn10200-*-*
3435 H8/500 simulator h8500-hitachi-hms or h8500hms
3436 HP/PA running BSD hppa*-*-bsd*
3437 HP/PA running OSF/1 hppa*-*-osf*
3438 HP/PA Pro target hppa*-*-pro*
3439 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3440 386BSD i[3456]86-*-bsd*
3441 Sequent family i[3456]86-sequent-sysv4*
3442 i[3456]86-sequent-sysv*
3443 i[3456]86-sequent-bsd*
3444 SPARC running LynxOS sparc-*-lynxos*
3445 SPARC running SunOS 4 sparc-*-sunos4*
3446 Tsqware Sparclet sparclet-*-*
3447 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3449 *** Changes in GDB 6.0:
3453 Support for debugging the Objective-C programming language has been
3454 integrated into GDB.
3456 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3458 DWARF 2's Call Frame Information makes available compiler generated
3459 information that more exactly describes the program's run-time stack.
3460 By using this information, GDB is able to provide more robust stack
3463 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3464 have been updated to use a new backtrace mechanism which includes
3465 DWARF 2 CFI support.
3469 GDB's remote protocol has been extended to include support for hosted
3470 file I/O (where the remote target uses GDB's file system). See GDB's
3471 remote protocol documentation for details.
3473 * All targets using the new architecture framework.
3475 All of GDB's targets have been updated to use the new internal
3476 architecture framework. The way is now open for future GDB releases
3477 to include cross-architecture native debugging support (i386 on amd64,
3480 * GNU/Linux's Thread Local Storage (TLS)
3482 GDB now includes support for for the GNU/Linux implementation of
3483 per-thread variables.
3485 * GNU/Linux's Native POSIX Thread Library (NPTL)
3487 GDB's thread code has been updated to work with either the new
3488 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3490 * Separate debug info.
3492 GDB, in conjunction with BINUTILS, now supports a mechanism for
3493 automatically loading debug information from a separate file. Instead
3494 of shipping full debug and non-debug versions of system libraries,
3495 system integrators can now instead ship just the stripped libraries
3496 and optional debug files.
3498 * DWARF 2 Location Expressions
3500 DWARF 2 Location Expressions allow the compiler to more completely
3501 describe the location of variables (even in optimized code) to the
3504 GDB now includes preliminary support for location expressions (support
3505 for DW_OP_piece is still missing).
3509 A number of long standing bugs that caused GDB to die while starting a
3510 Java application have been fixed. GDB's Java support is now
3511 considered "useable".
3513 * GNU/Linux support for fork, vfork, and exec.
3515 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3516 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3519 * GDB supports logging output to a file
3521 There are two new commands, "set logging" and "show logging", which can be
3522 used to capture GDB's output to a file.
3524 * The meaning of "detach" has changed for gdbserver
3526 The "detach" command will now resume the application, as documented. To
3527 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3530 * d10v, m68hc11 `regs' command deprecated
3532 The `info registers' command has been updated so that it displays the
3533 registers using a format identical to the old `regs' command.
3537 A new command, "maint set profile on/off", has been added. This command can
3538 be used to enable or disable profiling while running GDB, to profile a
3539 session or a set of commands. In addition there is a new configure switch,
3540 "--enable-profiling", which will cause GDB to be compiled with profiling
3541 data, for more informative profiling results.
3543 * Default MI syntax changed to "mi2".
3545 The default MI (machine interface) syntax, enabled by the command line
3546 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3547 "mi1", can be enabled by specifying the option "-i=mi1".
3549 Support for the original "mi0" syntax (included in GDB 5.0) has been
3552 Fix for gdb/192: removed extraneous space when displaying frame level.
3553 Fix for gdb/672: update changelist is now output in mi list format.
3554 Fix for gdb/702: a -var-assign that updates the value now shows up
3555 in a subsequent -var-update.
3557 * New native configurations.
3559 FreeBSD/amd64 x86_64-*-freebsd*
3561 * Multi-arched targets.
3563 HP/PA HPUX11 hppa*-*-hpux*
3564 Renesas M32R/D w/simulator m32r-*-elf*
3566 * OBSOLETE configurations and files
3568 Configurations that have been declared obsolete in this release have
3569 been commented out. Unless there is activity to revive these
3570 configurations, the next release of GDB will have their sources
3571 permanently REMOVED.
3573 Z8000 simulator z8k-zilog-none or z8ksim
3574 Matsushita MN10200 w/simulator mn10200-*-*
3575 H8/500 simulator h8500-hitachi-hms or h8500hms
3576 HP/PA running BSD hppa*-*-bsd*
3577 HP/PA running OSF/1 hppa*-*-osf*
3578 HP/PA Pro target hppa*-*-pro*
3579 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3580 Sequent family i[3456]86-sequent-sysv4*
3581 i[3456]86-sequent-sysv*
3582 i[3456]86-sequent-bsd*
3583 Tsqware Sparclet sparclet-*-*
3584 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3586 * REMOVED configurations and files
3589 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3590 IBM AIX PS/2 i[3456]86-*-aix
3591 i386 running Mach 3.0 i[3456]86-*-mach3*
3592 i386 running Mach i[3456]86-*-mach*
3593 i386 running OSF/1 i[3456]86-*osf1mk*
3594 HP/Apollo 68k Family m68*-apollo*-sysv*,
3596 m68*-hp-bsd*, m68*-hp-hpux*
3597 Argonaut Risc Chip (ARC) arc-*-*
3598 Mitsubishi D30V d30v-*-*
3599 Fujitsu FR30 fr30-*-elf*
3600 OS/9000 i[34]86-*-os9k
3601 I960 with MON960 i960-*-coff
3603 * MIPS $fp behavior changed
3605 The convenience variable $fp, for the MIPS, now consistently returns
3606 the address of the current frame's base. Previously, depending on the
3607 context, $fp could refer to either $sp or the current frame's base
3608 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3609 The GNU Source-Level Debugger''.
3611 *** Changes in GDB 5.3:
3613 * GNU/Linux shared library multi-threaded performance improved.
3615 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3616 `/proc', in preference to `ptrace' for memory reads. This may result
3617 in an improvement in the start-up time of multi-threaded, shared
3618 library applications when run under GDB. One GDB user writes: ``loads
3619 shared libs like mad''.
3621 * ``gdbserver'' now supports multi-threaded applications on some targets
3623 Support for debugging multi-threaded applications which use
3624 the GNU/Linux LinuxThreads package has been added for
3625 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3626 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3628 * GDB now supports C/C++ preprocessor macros.
3630 GDB now expands preprocessor macro invocations in C/C++ expressions,
3631 and provides various commands for showing macro definitions and how
3634 The new command `macro expand EXPRESSION' expands any macro
3635 invocations in expression, and shows the result.
3637 The new command `show macro MACRO-NAME' shows the definition of the
3638 macro named MACRO-NAME, and where it was defined.
3640 Most compilers don't include information about macros in the debugging
3641 information by default. In GCC 3.1, for example, you need to compile
3642 your program with the options `-gdwarf-2 -g3'. If the macro
3643 information is present in the executable, GDB will read it.
3645 * Multi-arched targets.
3647 DEC Alpha (partial) alpha*-*-*
3648 DEC VAX (partial) vax-*-*
3650 National Semiconductor NS32000 (partial) ns32k-*-*
3651 Motorola 68000 (partial) m68k-*-*
3652 Motorola MCORE mcore-*-*
3656 Fujitsu FRV architecture added by Red Hat frv*-*-*
3659 * New native configurations
3661 Alpha NetBSD alpha*-*-netbsd*
3662 SH NetBSD sh*-*-netbsdelf*
3663 MIPS NetBSD mips*-*-netbsd*
3664 UltraSPARC NetBSD sparc64-*-netbsd*
3666 * OBSOLETE configurations and files
3668 Configurations that have been declared obsolete in this release have
3669 been commented out. Unless there is activity to revive these
3670 configurations, the next release of GDB will have their sources
3671 permanently REMOVED.
3673 Mitsubishi D30V d30v-*-*
3674 OS/9000 i[34]86-*-os9k
3675 IBM AIX PS/2 i[3456]86-*-aix
3676 Fujitsu FR30 fr30-*-elf*
3677 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3678 Argonaut Risc Chip (ARC) arc-*-*
3679 i386 running Mach 3.0 i[3456]86-*-mach3*
3680 i386 running Mach i[3456]86-*-mach*
3681 i386 running OSF/1 i[3456]86-*osf1mk*
3682 HP/Apollo 68k Family m68*-apollo*-sysv*,
3684 m68*-hp-bsd*, m68*-hp-hpux*
3685 I960 with MON960 i960-*-coff
3687 * OBSOLETE languages
3689 CHILL, a Pascal like language used by telecommunications companies.
3691 * REMOVED configurations and files
3693 AMD 29k family via UDI a29k-amd-udi, udi29k
3694 A29K VxWorks a29k-*-vxworks
3695 AMD 29000 embedded, using EBMON a29k-none-none
3696 AMD 29000 embedded with COFF a29k-none-coff
3697 AMD 29000 embedded with a.out a29k-none-aout
3699 testsuite/gdb.hp/gdb.threads-hp/ directory
3701 * New command "set max-user-call-depth <nnn>"
3703 This command allows the user to limit the call depth of user-defined
3704 commands. The default is 1024.
3706 * Changes in FreeBSD/i386 native debugging.
3708 Support for the "generate-core-file" has been added.
3710 * New commands "dump", "append", and "restore".
3712 These commands allow data to be copied from target memory
3713 to a bfd-format or binary file (dump and append), and back
3714 from a file into memory (restore).
3716 * Improved "next/step" support on multi-processor Alpha Tru64.
3718 The previous single-step mechanism could cause unpredictable problems,
3719 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3720 of a software single-step mechanism prevents this.
3722 *** Changes in GDB 5.2.1:
3730 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3731 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3732 Fix, by Joel Brobecker imported from mainline.
3734 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3735 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3736 Fix, by Fred Fish, imported from mainline.
3738 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3739 Surprisingly enough, it works now.
3740 By Michal Ludvig, imported from mainline.
3742 i386 hardware watchpoint support:
3743 avoid misses on second run for some targets.
3744 By Pierre Muller, imported from mainline.
3746 *** Changes in GDB 5.2:
3748 * New command "set trust-readonly-sections on[off]".
3750 This command is a hint that tells gdb that read-only sections
3751 really are read-only (ie. that their contents will not change).
3752 In this mode, gdb will go to the object file rather than the
3753 target to read memory from read-only sections (such as ".text").
3754 This can be a significant performance improvement on some
3755 (notably embedded) targets.
3757 * New command "generate-core-file" (or "gcore").
3759 This new gdb command allows the user to drop a core file of the child
3760 process state at any time. So far it's been implemented only for
3761 GNU/Linux and Solaris, but should be relatively easily ported to other
3762 hosts. Argument is core file name (defaults to core.<pid>).
3764 * New command line option
3766 GDB now accepts --pid or -p followed by a process id.
3768 * Change in command line behavior -- corefiles vs. process ids.
3770 There is a subtle behavior in the way in which GDB handles
3771 command line arguments. The first non-flag argument is always
3772 a program to debug, but the second non-flag argument may either
3773 be a corefile or a process id. Previously, GDB would attempt to
3774 open the second argument as a corefile, and if that failed, would
3775 issue a superfluous error message and then attempt to attach it as
3776 a process. Now, if the second argument begins with a non-digit,
3777 it will be treated as a corefile. If it begins with a digit,
3778 GDB will attempt to attach it as a process, and if no such process
3779 is found, will then attempt to open it as a corefile.
3781 * Changes in ARM configurations.
3783 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3784 configuration is fully multi-arch.
3786 * New native configurations
3788 ARM NetBSD arm*-*-netbsd*
3789 x86 OpenBSD i[3456]86-*-openbsd*
3790 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3791 Sparc64 running FreeBSD sparc64-*-freebsd*
3795 Sanyo XStormy16 xstormy16-elf
3797 * OBSOLETE configurations and files
3799 Configurations that have been declared obsolete in this release have
3800 been commented out. Unless there is activity to revive these
3801 configurations, the next release of GDB will have their sources
3802 permanently REMOVED.
3804 AMD 29k family via UDI a29k-amd-udi, udi29k
3805 A29K VxWorks a29k-*-vxworks
3806 AMD 29000 embedded, using EBMON a29k-none-none
3807 AMD 29000 embedded with COFF a29k-none-coff
3808 AMD 29000 embedded with a.out a29k-none-aout
3810 testsuite/gdb.hp/gdb.threads-hp/ directory
3812 * REMOVED configurations and files
3814 TI TMS320C80 tic80-*-*
3816 PowerPC Solaris powerpcle-*-solaris*
3817 PowerPC Windows NT powerpcle-*-cygwin32
3818 PowerPC Netware powerpc-*-netware*
3819 Harris/CXUX m88k m88*-harris-cxux*
3820 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3821 ns32k-utek-sysv* ns32k-utek-*
3822 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3823 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3824 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3825 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3826 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3828 * Changes to command line processing
3830 The new `--args' feature can be used to specify command-line arguments
3831 for the inferior from gdb's command line.
3833 * Changes to key bindings
3835 There is a new `operate-and-get-next' function bound to `C-o'.
3837 *** Changes in GDB 5.1.1
3839 Fix compile problem on DJGPP.
3841 Fix a problem with floating-point registers on the i386 being
3844 Fix to stop GDB crashing on .debug_str debug info.
3846 Numerous documentation fixes.
3848 Numerous testsuite fixes.
3850 *** Changes in GDB 5.1:
3852 * New native configurations
3854 Alpha FreeBSD alpha*-*-freebsd*
3855 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3856 MIPS GNU/Linux mips*-*-linux*
3857 MIPS SGI Irix 6.x mips*-sgi-irix6*
3858 ia64 AIX ia64-*-aix*
3859 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3863 Motorola 68HC11 and 68HC12 m68hc11-elf
3865 UltraSparc running GNU/Linux sparc64-*-linux*
3867 * OBSOLETE configurations and files
3869 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3870 Harris/CXUX m88k m88*-harris-cxux*
3871 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3872 ns32k-utek-sysv* ns32k-utek-*
3873 TI TMS320C80 tic80-*-*
3875 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3876 PowerPC Solaris powerpcle-*-solaris*
3877 PowerPC Windows NT powerpcle-*-cygwin32
3878 PowerPC Netware powerpc-*-netware*
3879 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3880 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3881 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3882 Apple Macintosh (MPW) host N/A
3884 stuff.c (Program to stuff files into a specially prepared space in kdb)
3885 kdb-start.c (Main loop for the standalone kernel debugger)
3887 Configurations that have been declared obsolete in this release have
3888 been commented out. Unless there is activity to revive these
3889 configurations, the next release of GDB will have their sources
3890 permanently REMOVED.
3892 * REMOVED configurations and files
3894 Altos 3068 m68*-altos-*
3895 Convex c1-*-*, c2-*-*
3897 ARM RISCix arm-*-* (as host)
3901 * GDB has been converted to ISO C.
3903 GDB's source code has been converted to ISO C. In particular, the
3904 sources are fully protoized, and rely on standard headers being
3909 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3911 * The MI enabled by default.
3913 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3914 revised and enabled by default. Packages which use GDB as a debugging
3915 engine behind a UI or another front end are encouraged to switch to
3916 using the GDB/MI interface, instead of the old annotations interface
3917 which is now deprecated.
3919 * Support for debugging Pascal programs.
3921 GDB now includes support for debugging Pascal programs. The following
3922 main features are supported:
3924 - Pascal-specific data types such as sets;
3926 - automatic recognition of Pascal sources based on file-name
3929 - Pascal-style display of data types, variables, and functions;
3931 - a Pascal expression parser.
3933 However, some important features are not yet supported.
3935 - Pascal string operations are not supported at all;
3937 - there are some problems with boolean types;
3939 - Pascal type hexadecimal constants are not supported
3940 because they conflict with the internal variables format;
3942 - support for Pascal objects and classes is not full yet;
3944 - unlike Pascal, GDB is case-sensitive for symbol names.
3946 * Changes in completion.
3948 Commands such as `shell', `run' and `set args', which pass arguments
3949 to inferior programs, now complete on file names, similar to what
3950 users expect at the shell prompt.
3952 Commands which accept locations, such as `disassemble', `print',
3953 `breakpoint', `until', etc. now complete on filenames as well as
3954 program symbols. Thus, if you type "break foob TAB", and the source
3955 files linked into the programs include `foobar.c', that file name will
3956 be one of the candidates for completion. However, file names are not
3957 considered for completion after you typed a colon that delimits a file
3958 name from a name of a function in that file, as in "break foo.c:bar".
3960 `set demangle-style' completes on available demangling styles.
3962 * New platform-independent commands:
3964 It is now possible to define a post-hook for a command as well as a
3965 hook that runs before the command. For more details, see the
3966 documentation of `hookpost' in the GDB manual.
3968 * Changes in GNU/Linux native debugging.
3970 Support for debugging multi-threaded programs has been completely
3971 revised for all platforms except m68k and sparc. You can now debug as
3972 many threads as your system allows you to have.
3974 Attach/detach is supported for multi-threaded programs.
3976 Support for SSE registers was added for x86. This doesn't work for
3977 multi-threaded programs though.
3979 * Changes in MIPS configurations.
3981 Multi-arch support is enabled for all MIPS configurations.
3983 GDB can now be built as native debugger on SGI Irix 6.x systems for
3984 debugging n32 executables. (Debugging 64-bit executables is not yet
3987 * Unified support for hardware watchpoints in all x86 configurations.
3989 Most (if not all) native x86 configurations support hardware-assisted
3990 breakpoints and watchpoints in a unified manner. This support
3991 implements debug register sharing between watchpoints, which allows to
3992 put a virtually infinite number of watchpoints on the same address,
3993 and also supports watching regions up to 16 bytes with several debug
3996 The new maintenance command `maintenance show-debug-regs' toggles
3997 debugging print-outs in functions that insert, remove, and test
3998 watchpoints and hardware breakpoints.
4000 * Changes in the DJGPP native configuration.
4002 New command ``info dos sysinfo'' displays assorted information about
4003 the CPU, OS, memory, and DPMI server.
4005 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
4006 display information about segment descriptors stored in GDT, LDT, and
4009 New commands ``info dos pde'' and ``info dos pte'' display entries
4010 from Page Directory and Page Tables (for now works with CWSDPMI only).
4011 New command ``info dos address-pte'' displays the Page Table entry for
4012 a given linear address.
4014 GDB can now pass command lines longer than 126 characters to the
4015 program being debugged (requires an update to the libdbg.a library
4016 which is part of the DJGPP development kit).
4018 DWARF2 debug info is now supported.
4020 It is now possible to `step' and `next' through calls to `longjmp'.
4022 * Changes in documentation.
4024 All GDB documentation was converted to GFDL, the GNU Free
4025 Documentation License.
4027 Tracepoints-related commands are now fully documented in the GDB
4030 TUI, the Text-mode User Interface, is now documented in the manual.
4032 Tracepoints-related commands are now fully documented in the GDB
4035 The "GDB Internals" manual now has an index. It also includes
4036 documentation of `ui_out' functions, GDB coding standards, x86
4037 hardware watchpoints, and memory region attributes.
4039 * GDB's version number moved to ``version.in''
4041 The Makefile variable VERSION has been replaced by the file
4042 ``version.in''. People creating GDB distributions should update the
4043 contents of this file.
4047 GUD support is now a standard part of the EMACS distribution.
4049 *** Changes in GDB 5.0:
4051 * Improved support for debugging FP programs on x86 targets
4053 Unified and much-improved support for debugging floating-point
4054 programs on all x86 targets. In particular, ``info float'' now
4055 displays the FP registers in the same format on all x86 targets, with
4056 greater level of detail.
4058 * Improvements and bugfixes in hardware-assisted watchpoints
4060 It is now possible to watch array elements, struct members, and
4061 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4062 on x86 targets no longer erroneously trigger when the address is
4065 * Improvements in the native DJGPP version of GDB
4067 The distribution now includes all the scripts and auxiliary files
4068 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4069 machines ``out of the box''.
4071 The DJGPP version can now debug programs that use signals. It is
4072 possible to catch signals that happened in the debuggee, deliver
4073 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4074 would kill the program being debugged.) Programs that hook hardware
4075 interrupts (keyboard, timer, etc.) can also be debugged.
4077 It is now possible to debug DJGPP programs that redirect their
4078 standard handles or switch them to raw (as opposed to cooked) mode, or
4079 even close them. The command ``run < foo > bar'' works as expected,
4080 and ``info terminal'' reports useful information about the debuggee's
4081 terminal, including raw/cooked mode, redirection, etc.
4083 The DJGPP version now uses termios functions for console I/O, which
4084 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4087 DOS-style file names with drive letters are now fully supported by
4090 It is now possible to debug DJGPP programs that switch their working
4091 directory. It is also possible to rerun the debuggee any number of
4092 times without restarting GDB; thus, you can use the same setup,
4093 breakpoints, etc. for many debugging sessions.
4095 * New native configurations
4097 ARM GNU/Linux arm*-*-linux*
4098 PowerPC GNU/Linux powerpc-*-linux*
4102 Motorola MCore mcore-*-*
4103 x86 VxWorks i[3456]86-*-vxworks*
4104 PowerPC VxWorks powerpc-*-vxworks*
4105 TI TMS320C80 tic80-*-*
4107 * OBSOLETE configurations
4109 Altos 3068 m68*-altos-*
4110 Convex c1-*-*, c2-*-*
4112 ARM RISCix arm-*-* (as host)
4115 Configurations that have been declared obsolete will be commented out,
4116 but the code will be left in place. If there is no activity to revive
4117 these configurations before the next release of GDB, the sources will
4118 be permanently REMOVED.
4120 * Gould support removed
4122 Support for the Gould PowerNode and NP1 has been removed.
4124 * New features for SVR4
4126 On SVR4 native platforms (such as Solaris), if you attach to a process
4127 without first loading a symbol file, GDB will now attempt to locate and
4128 load symbols from the running process's executable file.
4130 * Many C++ enhancements
4132 C++ support has been greatly improved. Overload resolution now works properly
4133 in almost all cases. RTTI support is on the way.
4135 * Remote targets can connect to a sub-program
4137 A popen(3) style serial-device has been added. This device starts a
4138 sub-process (such as a stand-alone simulator) and then communicates
4139 with that. The sub-program to run is specified using the syntax
4140 ``|<program> <args>'' vis:
4142 (gdb) set remotedebug 1
4143 (gdb) target extended-remote |mn10300-elf-sim program-args
4145 * MIPS 64 remote protocol
4147 A long standing bug in the mips64 remote protocol where by GDB
4148 expected certain 32 bit registers (ex SR) to be transfered as 32
4149 instead of 64 bits has been fixed.
4151 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4152 added to provide backward compatibility with older versions of GDB.
4154 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4156 The command ``set remotebinarydownload'' command has been replaced by
4157 ``set remote X-packet''. Other commands in ``set remote'' family
4158 include ``set remote P-packet''.
4160 * Breakpoint commands accept ranges.
4162 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4163 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4164 ``tracepoint passcount'' also accepts a range of tracepoints.
4166 * ``apropos'' command added.
4168 The ``apropos'' command searches through command names and
4169 documentation strings, printing out matches, making it much easier to
4170 try to find a command that does what you are looking for.
4174 A new machine oriented interface (MI) has been added to GDB. This
4175 interface is designed for debug environments running GDB as a separate
4176 process. This is part of the long term libGDB project. See the
4177 "GDB/MI" chapter of the GDB manual for further information. It can be
4178 enabled by configuring with:
4180 .../configure --enable-gdbmi
4182 *** Changes in GDB-4.18:
4184 * New native configurations
4186 HP-UX 10.20 hppa*-*-hpux10.20
4187 HP-UX 11.x hppa*-*-hpux11.0*
4188 M68K GNU/Linux m68*-*-linux*
4192 Fujitsu FR30 fr30-*-elf*
4193 Intel StrongARM strongarm-*-*
4194 Mitsubishi D30V d30v-*-*
4196 * OBSOLETE configurations
4198 Gould PowerNode, NP1 np1-*-*, pn-*-*
4200 Configurations that have been declared obsolete will be commented out,
4201 but the code will be left in place. If there is no activity to revive
4202 these configurations before the next release of GDB, the sources will
4203 be permanently REMOVED.
4207 As a compatibility experiment, GDB's source files buildsym.h and
4208 buildsym.c have been converted to pure standard C, no longer
4209 containing any K&R compatibility code. We believe that all systems in
4210 use today either come with a standard C compiler, or have a GCC port
4211 available. If this is not true, please report the affected
4212 configuration to bug-gdb@gnu.org immediately. See the README file for
4213 information about getting a standard C compiler if you don't have one
4218 GDB now uses readline 2.2.
4220 * set extension-language
4222 You can now control the mapping between filename extensions and source
4223 languages by using the `set extension-language' command. For instance,
4224 you can ask GDB to treat .c files as C++ by saying
4225 set extension-language .c c++
4226 The command `info extensions' lists all of the recognized extensions
4227 and their associated languages.
4229 * Setting processor type for PowerPC and RS/6000
4231 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4232 you can use the `set processor' command to specify what variant of the
4233 PowerPC family you are debugging. The command
4237 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4238 following PowerPC and RS6000 variants:
4240 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4241 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4243 403GC IBM PowerPC 403GC
4244 505 Motorola PowerPC 505
4245 860 Motorola PowerPC 860 or 850
4246 601 Motorola PowerPC 601
4247 602 Motorola PowerPC 602
4248 603 Motorola/IBM PowerPC 603 or 603e
4249 604 Motorola PowerPC 604 or 604e
4250 750 Motorola/IBM PowerPC 750 or 750
4252 At the moment, this command just tells GDB what to name the
4253 special-purpose processor registers. Since almost all the affected
4254 registers are inaccessible to user-level programs, this command is
4255 only useful for remote debugging in its present form.
4259 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4260 more extensive support for HP-UX. Added features include shared
4261 library support, kernel threads and hardware watchpoints for 11.00,
4262 support for HP's ANSI C and C++ compilers, and a compatibility mode
4263 for xdb and dbx commands.
4267 HP's donation includes the new concept of catchpoints, which is a
4268 generalization of the old catch command. On HP-UX, it is now possible
4269 to catch exec, fork, and vfork, as well as library loading.
4271 This means that the existing catch command has changed; its first
4272 argument now specifies the type of catch to be set up. See the
4273 output of "help catch" for a list of catchpoint types.
4275 * Debugging across forks
4277 On HP-UX, you can choose which process to debug when a fork() happens
4282 HP has donated a curses-based terminal user interface (TUI). To get
4283 it, build with --enable-tui. Although this can be enabled for any
4284 configuration, at present it only works for native HP debugging.
4286 * GDB remote protocol additions
4288 A new protocol packet 'X' that writes binary data is now available.
4289 Default behavior is to try 'X', then drop back to 'M' if the stub
4290 fails to respond. The settable variable `remotebinarydownload'
4291 allows explicit control over the use of 'X'.
4293 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4294 full 64-bit address. The command
4296 set remoteaddresssize 32
4298 can be used to revert to the old behaviour. For existing remote stubs
4299 the change should not be noticed, as the additional address information
4302 In order to assist in debugging stubs, you may use the maintenance
4303 command `packet' to send any text string to the stub. For instance,
4305 maint packet heythere
4307 sends the packet "$heythere#<checksum>". Note that it is very easy to
4308 disrupt a debugging session by sending the wrong packet at the wrong
4311 The compare-sections command allows you to compare section data on the
4312 target to what is in the executable file without uploading or
4313 downloading, by comparing CRC checksums.
4315 * Tracing can collect general expressions
4317 You may now collect general expressions at tracepoints. This requires
4318 further additions to the target-side stub; see tracepoint.c and
4319 doc/agentexpr.texi for further details.
4321 * mask-address variable for Mips
4323 For Mips targets, you may control the zeroing of the upper 32 bits of
4324 a 64-bit address by entering `set mask-address on'. This is mainly
4325 of interest to users of embedded R4xxx and R5xxx processors.
4327 * Higher serial baud rates
4329 GDB's serial code now allows you to specify baud rates 57600, 115200,
4330 230400, and 460800 baud. (Note that your host system may not be able
4331 to achieve all of these rates.)
4335 The i960 configuration now includes an initial implementation of a
4336 builtin simulator, contributed by Jim Wilson.
4339 *** Changes in GDB-4.17:
4341 * New native configurations
4343 Alpha GNU/Linux alpha*-*-linux*
4344 Unixware 2.x i[3456]86-unixware2*
4345 Irix 6.x mips*-sgi-irix6*
4346 PowerPC GNU/Linux powerpc-*-linux*
4347 PowerPC Solaris powerpcle-*-solaris*
4348 Sparc GNU/Linux sparc-*-linux*
4349 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4353 Argonaut Risc Chip (ARC) arc-*-*
4354 Hitachi H8/300S h8300*-*-*
4355 Matsushita MN10200 w/simulator mn10200-*-*
4356 Matsushita MN10300 w/simulator mn10300-*-*
4357 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4358 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4359 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4360 Mitsubishi D10V w/simulator d10v-*-*
4361 Mitsubishi M32R/D w/simulator m32r-*-elf*
4362 Tsqware Sparclet sparclet-*-*
4363 NEC V850 w/simulator v850-*-*
4365 * New debugging protocols
4367 ARM with RDI protocol arm*-*-*
4368 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4369 DDB and LSI variants of PMON protocol mips*-*-*
4370 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4371 PowerPC with SDS protocol powerpc{,le}-*-eabi
4372 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4376 All configurations can now understand and use the DWARF 2 debugging
4377 format. The choice is automatic, if the symbol file contains DWARF 2
4382 GDB now includes basic Java language support. This support is
4383 only useful with Java compilers that produce native machine code.
4385 * solib-absolute-prefix and solib-search-path
4387 For SunOS and SVR4 shared libraries, you may now set the prefix for
4388 loading absolute shared library symbol files, and the search path for
4389 locating non-absolute shared library symbol files.
4391 * Live range splitting
4393 GDB can now effectively debug code for which GCC has performed live
4394 range splitting as part of its optimization. See gdb/doc/LRS for
4395 more details on the expected format of the stabs information.
4399 GDB's support for the GNU Hurd, including thread debugging, has been
4400 updated to work with current versions of the Hurd.
4404 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4405 instruction set. ARM GDB automatically detects when Thumb
4406 instructions are in use, and adjusts disassembly and backtracing
4411 GDB's MIPS target configurations now handle the MIP16 16-bit
4416 GDB now includes support for overlays; if an executable has been
4417 linked such that multiple sections are based at the same address, GDB
4418 will decide which section to use for symbolic info. You can choose to
4419 control the decision manually, using overlay commands, or implement
4420 additional target-side support and use "overlay load-target" to bring
4421 in the overlay mapping. Do "help overlay" for more detail.
4425 The command "info symbol <address>" displays information about
4426 the symbol at the specified address.
4430 The standard remote protocol now includes an extension that allows
4431 asynchronous collection and display of trace data. This requires
4432 extensive support in the target-side debugging stub. Tracing mode
4433 includes a new interaction mode in GDB and new commands: see the
4434 file tracepoint.c for more details.
4438 Configurations for embedded MIPS now include a simulator contributed
4439 by Cygnus Solutions. The simulator supports the instruction sets
4440 of most MIPS variants.
4444 Sparc configurations may now include the ERC32 simulator contributed
4445 by the European Space Agency. The simulator is not built into
4446 Sparc targets by default; configure with --enable-sim to include it.
4450 For target configurations that may include multiple variants of a
4451 basic architecture (such as MIPS and SH), you may now set the
4452 architecture explicitly. "set arch" sets, "info arch" lists
4453 the possible architectures.
4455 *** Changes in GDB-4.16:
4457 * New native configurations
4459 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4460 M68K NetBSD m68k-*-netbsd*
4461 PowerPC AIX 4.x powerpc-*-aix*
4462 PowerPC MacOS powerpc-*-macos*
4463 PowerPC Windows NT powerpcle-*-cygwin32
4464 RS/6000 AIX 4.x rs6000-*-aix4*
4468 ARM with RDP protocol arm-*-*
4469 I960 with MON960 i960-*-coff
4470 MIPS VxWorks mips*-*-vxworks*
4471 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4472 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4474 Matra Sparclet sparclet-*-*
4478 The powerpc-eabi configuration now includes the PSIM simulator,
4479 contributed by Andrew Cagney, with assistance from Mike Meissner.
4480 PSIM is a very elaborate model of the PowerPC, including not only
4481 basic instruction set execution, but also details of execution unit
4482 performance and I/O hardware. See sim/ppc/README for more details.
4486 GDB now works with Solaris 2.5.
4488 * Windows 95/NT native
4490 GDB will now work as a native debugger on Windows 95 and Windows NT.
4491 To build it from source, you must use the "gnu-win32" environment,
4492 which uses a DLL to emulate enough of Unix to run the GNU tools.
4493 Further information, binaries, and sources are available at
4494 ftp.cygnus.com, under pub/gnu-win32.
4496 * dont-repeat command
4498 If a user-defined command includes the command `dont-repeat', then the
4499 command will not be repeated if the user just types return. This is
4500 useful if the command is time-consuming to run, so that accidental
4501 extra keystrokes don't run the same command many times.
4503 * Send break instead of ^C
4505 The standard remote protocol now includes an option to send a break
4506 rather than a ^C to the target in order to interrupt it. By default,
4507 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4509 * Remote protocol timeout
4511 The standard remote protocol includes a new variable `remotetimeout'
4512 that allows you to set the number of seconds before GDB gives up trying
4513 to read from the target. The default value is 2.
4515 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4517 By default GDB will automatically keep track of objects as they are
4518 loaded and unloaded by the dynamic linker. By using the command `set
4519 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4520 when shared library events occur, thus allowing you to set breakpoints
4521 in shared libraries which are explicitly loaded by the inferior.
4523 Note this feature does not work on hpux8. On hpux9 you must link
4524 /usr/lib/end.o into your program. This feature should work
4525 automatically on hpux10.
4527 * Irix 5.x hardware watchpoint support
4529 Irix 5 configurations now support the use of hardware watchpoints.
4531 * Mips protocol "SYN garbage limit"
4533 When debugging a Mips target using the `target mips' protocol, you
4534 may set the number of characters that GDB will ignore by setting
4535 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4536 every character. The default value is 1050.
4538 * Recording and replaying remote debug sessions
4540 If you set `remotelogfile' to the name of a file, gdb will write to it
4541 a recording of a remote debug session. This recording may then be
4542 replayed back to gdb using "gdbreplay". See gdbserver/README for
4543 details. This is useful when you have a problem with GDB while doing
4544 remote debugging; you can make a recording of the session and send it
4545 to someone else, who can then recreate the problem.
4547 * Speedups for remote debugging
4549 GDB includes speedups for downloading and stepping MIPS systems using
4550 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4551 and more efficient S-record downloading.
4553 * Memory use reductions and statistics collection
4555 GDB now uses less memory and reports statistics about memory usage.
4556 Try the `maint print statistics' command, for example.
4558 *** Changes in GDB-4.15:
4560 * Psymtabs for XCOFF
4562 The symbol reader for AIX GDB now uses partial symbol tables. This
4563 can greatly improve startup time, especially for large executables.
4565 * Remote targets use caching
4567 Remote targets now use a data cache to speed up communication with the
4568 remote side. The data cache could lead to incorrect results because
4569 it doesn't know about volatile variables, thus making it impossible to
4570 debug targets which use memory mapped I/O devices. `set remotecache
4571 off' turns the the data cache off.
4573 * Remote targets may have threads
4575 The standard remote protocol now includes support for multiple threads
4576 in the target system, using new protocol commands 'H' and 'T'. See
4577 gdb/remote.c for details.
4581 If GDB is configured with `--enable-netrom', then it will include
4582 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4583 acts as though it is a bank of ROM on the target board, but you can
4584 write into it over the network. GDB's support consists only of
4585 support for fast loading into the emulated ROM; to debug, you must use
4586 another protocol, such as standard remote protocol. The usual
4587 sequence is something like
4589 target nrom <netrom-hostname>
4591 target remote <netrom-hostname>:1235
4595 GDB now includes support for the Apple Macintosh, as a host only. It
4596 may be run as either an MPW tool or as a standalone application, and
4597 it can debug through the serial port. All the usual GDB commands are
4598 available, but to the target command, you must supply "serial" as the
4599 device type instead of "/dev/ttyXX". See mpw-README in the main
4600 directory for more information on how to build. The MPW configuration
4601 scripts */mpw-config.in support only a few targets, and only the
4602 mips-idt-ecoff target has been tested.
4606 GDB configuration now uses autoconf. This is not user-visible,
4607 but does simplify configuration and building.
4611 GDB now supports hpux10.
4613 *** Changes in GDB-4.14:
4615 * New native configurations
4617 x86 FreeBSD i[345]86-*-freebsd
4618 x86 NetBSD i[345]86-*-netbsd
4619 NS32k NetBSD ns32k-*-netbsd
4620 Sparc NetBSD sparc-*-netbsd
4624 A29K VxWorks a29k-*-vxworks
4625 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4626 CPU32 EST-300 emulator m68*-*-est*
4627 PowerPC ELF powerpc-*-elf
4630 * Alpha OSF/1 support for procfs
4632 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4633 possible to attach to running processes. As the mounting of the /proc
4634 filesystem is optional on the Alpha, GDB automatically determines
4635 the availability of /proc during startup. This can lead to problems
4636 if /proc is unmounted after GDB has been started.
4638 * Arguments to user-defined commands
4640 User commands may accept up to 10 arguments separated by whitespace.
4641 Arguments are accessed within the user command via $arg0..$arg9. A
4644 print $arg0 + $arg1 + $arg2
4646 To execute the command use:
4649 Defines the command "adder" which prints the sum of its three arguments.
4650 Note the arguments are text substitutions, so they may reference variables,
4651 use complex expressions, or even perform inferior function calls.
4653 * New `if' and `while' commands
4655 This makes it possible to write more sophisticated user-defined
4656 commands. Both commands take a single argument, which is the
4657 expression to evaluate, and must be followed by the commands to
4658 execute, one per line, if the expression is nonzero, the list being
4659 terminated by the word `end'. The `if' command list may include an
4660 `else' word, which causes the following commands to be executed only
4661 if the expression is zero.
4663 * Fortran source language mode
4665 GDB now includes partial support for Fortran 77. It will recognize
4666 Fortran programs and can evaluate a subset of Fortran expressions, but
4667 variables and functions may not be handled correctly. GDB will work
4668 with G77, but does not yet know much about symbols emitted by other
4671 * Better HPUX support
4673 Most debugging facilities now work on dynamic executables for HPPAs
4674 running hpux9 or later. You can attach to running dynamically linked
4675 processes, but by default the dynamic libraries will be read-only, so
4676 for instance you won't be able to put breakpoints in them. To change
4677 that behavior do the following before running the program:
4683 This will cause the libraries to be mapped private and read-write.
4684 To revert to the normal behavior, do this:
4690 You cannot set breakpoints or examine data in the library until after
4691 the library is loaded if the function/data symbols do not have
4694 GDB can now also read debug symbols produced by the HP C compiler on
4695 HPPAs (sorry, no C++, Fortran or 68k support).
4697 * Target byte order now dynamically selectable
4699 You can choose which byte order to use with a target system, via the
4700 commands "set endian big" and "set endian little", and you can see the
4701 current setting by using "show endian". You can also give the command
4702 "set endian auto", in which case GDB will use the byte order
4703 associated with the executable. Currently, only embedded MIPS
4704 configurations support dynamic selection of target byte order.
4706 * New DOS host serial code
4708 This version uses DPMI interrupts to handle buffered I/O, so you
4709 no longer need to run asynctsr when debugging boards connected to
4712 *** Changes in GDB-4.13:
4714 * New "complete" command
4716 This lists all the possible completions for the rest of the line, if it
4717 were to be given as a command itself. This is intended for use by emacs.
4719 * Trailing space optional in prompt
4721 "set prompt" no longer adds a space for you after the prompt you set. This
4722 allows you to set a prompt which ends in a space or one that does not.
4724 * Breakpoint hit counts
4726 "info break" now displays a count of the number of times the breakpoint
4727 has been hit. This is especially useful in conjunction with "ignore"; you
4728 can ignore a large number of breakpoint hits, look at the breakpoint info
4729 to see how many times the breakpoint was hit, then run again, ignoring one
4730 less than that number, and this will get you quickly to the last hit of
4733 * Ability to stop printing at NULL character
4735 "set print null-stop" will cause GDB to stop printing the characters of
4736 an array when the first NULL is encountered. This is useful when large
4737 arrays actually contain only short strings.
4739 * Shared library breakpoints
4741 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4742 breakpoints in shared libraries before the executable is run.
4744 * Hardware watchpoints
4746 There is a new hardware breakpoint for the watch command for sparclite
4747 targets. See gdb/sparclite/hw_breakpoint.note.
4749 Hardware watchpoints are also now supported under GNU/Linux.
4753 Annotations have been added. These are for use with graphical interfaces,
4754 and are still experimental. Currently only gdba.el uses these.
4756 * Improved Irix 5 support
4758 GDB now works properly with Irix 5.2.
4760 * Improved HPPA support
4762 GDB now works properly with the latest GCC and GAS.
4764 * New native configurations
4766 Sequent PTX4 i[34]86-sequent-ptx4
4767 HPPA running OSF/1 hppa*-*-osf*
4768 Atari TT running SVR4 m68*-*-sysv4*
4769 RS/6000 LynxOS rs6000-*-lynxos*
4773 OS/9000 i[34]86-*-os9k
4774 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4777 * Hitachi SH7000 and E7000-PC ICE support
4779 There is now support for communicating with the Hitachi E7000-PC ICE.
4780 This is available automatically when GDB is configured for the SH.
4784 As usual, a variety of small fixes and improvements, both generic
4785 and configuration-specific. See the ChangeLog for more detail.
4787 *** Changes in GDB-4.12:
4789 * Irix 5 is now supported
4793 GDB-4.12 on the HPPA has a number of changes which make it unable
4794 to debug the output from the currently released versions of GCC and
4795 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4796 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4797 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4800 *** Changes in GDB-4.11:
4802 * User visible changes:
4806 The "set remotedebug" option is now consistent between the mips remote
4807 target, remote targets using the gdb-specific protocol, UDI (AMD's
4808 debug protocol for the 29k) and the 88k bug monitor. It is now an
4809 integer specifying a debug level (normally 0 or 1, but 2 means more
4810 debugging info for the mips target).
4812 * DEC Alpha native support
4814 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4815 debug info, but GDB works fairly well with the DEC compiler and should
4816 work with a future GCC release. See the README file for a few
4817 Alpha-specific notes.
4819 * Preliminary thread implementation
4821 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4823 * LynxOS native and target support for 386
4825 This release has been hosted on LynxOS 2.2, and also can be configured
4826 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4829 * Improvements in C++ mangling/demangling.
4831 This release has much better g++ debugging, specifically in name
4832 mangling/demangling, virtual function calls, print virtual table,
4833 call methods, ...etc.
4835 *** Changes in GDB-4.10:
4837 * User visible changes:
4839 Remote debugging using the GDB-specific (`target remote') protocol now
4840 supports the `load' command. This is only useful if you have some
4841 other way of getting the stub to the target system, and you can put it
4842 somewhere in memory where it won't get clobbered by the download.
4844 Filename completion now works.
4846 When run under emacs mode, the "info line" command now causes the
4847 arrow to point to the line specified. Also, "info line" prints
4848 addresses in symbolic form (as well as hex).
4850 All vxworks based targets now support a user settable option, called
4851 vxworks-timeout. This option represents the number of seconds gdb
4852 should wait for responses to rpc's. You might want to use this if
4853 your vxworks target is, perhaps, a slow software simulator or happens
4854 to be on the far side of a thin network line.
4858 This release contains support for using a DEC alpha as a GDB host for
4859 cross debugging. Native alpha debugging is not supported yet.
4862 *** Changes in GDB-4.9:
4866 This is the first GDB release which is accompanied by a matching testsuite.
4867 The testsuite requires installation of dejagnu, which should be available
4868 via ftp from most sites that carry GNU software.
4872 'Cfront' style demangling has had its name changed to 'ARM' style, to
4873 emphasize that it was written from the specifications in the C++ Annotated
4874 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4875 disclaimers, it still generated too much confusion with users attempting to
4876 use gdb with AT&T cfront.
4880 GDB now uses a standard remote interface to a simulator library.
4881 So far, the library contains simulators for the Zilog Z8001/2, the
4882 Hitachi H8/300, H8/500 and Super-H.
4884 * New targets supported
4886 H8/300 simulator h8300-hitachi-hms or h8300hms
4887 H8/500 simulator h8500-hitachi-hms or h8500hms
4888 SH simulator sh-hitachi-hms or sh
4889 Z8000 simulator z8k-zilog-none or z8ksim
4890 IDT MIPS board over serial line mips-idt-ecoff
4892 Cross-debugging to GO32 targets is supported. It requires a custom
4893 version of the i386-stub.c module which is integrated with the
4894 GO32 memory extender.
4896 * New remote protocols
4898 MIPS remote debugging protocol.
4900 * New source languages supported
4902 This version includes preliminary support for Chill, a Pascal like language
4903 used by telecommunications companies. Chill support is also being integrated
4904 into the GNU compiler, but we don't know when it will be publically available.
4907 *** Changes in GDB-4.8:
4909 * HP Precision Architecture supported
4911 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4912 version of this support was available as a set of patches from the
4913 University of Utah. GDB does not support debugging of programs
4914 compiled with the HP compiler, because HP will not document their file
4915 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4916 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4918 Many problems in the preliminary version have been fixed.
4920 * Faster and better demangling
4922 We have improved template demangling and fixed numerous bugs in the GNU style
4923 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4924 character types (wchar_t) are now supported. Demangling of each symbol is now
4925 only done once, and is cached when the symbol table for a file is read in.
4926 This results in a small increase in memory usage for C programs, a moderate
4927 increase in memory usage for C++ programs, and a fantastic speedup in
4930 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4931 from the specifications in the Annotated Reference Manual, which AT&T's
4932 compiler does not actually implement.
4934 * G++ multiple inheritance compiler problem
4936 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4937 inheritance lattices was reworked to properly discover ambiguities. We
4938 recently found an example which causes this new algorithm to fail in a
4939 very subtle way, producing bad debug information for those classes.
4940 The file 'gcc.patch' (in this directory) can be applied to gcc to
4941 circumvent the problem. A future GCC release will contain a complete
4944 The previous G++ debug info problem (mentioned below for the gdb-4.7
4945 release) is fixed in gcc version 2.3.2.
4947 * Improved configure script
4949 The `configure' script will now attempt to guess your system type if
4950 you don't supply a host system type. The old scheme of supplying a
4951 host system triplet is preferable over using this. All the magic is
4952 done in the new `config.guess' script. Examine it for details.
4954 We have also brought our configure script much more in line with the FSF's
4955 version. It now supports the --with-xxx options. In particular,
4956 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4957 The resulting GDB will not be able to read arbitrary object file formats --
4958 only the format ``expected'' to be used on the configured target system.
4959 We hope to make this the default in a future release.
4961 * Documentation improvements
4963 There's new internal documentation on how to modify GDB, and how to
4964 produce clean changes to the code. We implore people to read it
4965 before submitting changes.
4967 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4968 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4969 `info' files are also provided. To build `info' files from scratch,
4970 you will need the latest `makeinfo' release, which will be available in
4971 a future texinfo-X.Y release.
4973 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4974 We're not sure exactly which versions have this problem, but it has
4975 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4976 or better. If that isn't possible, there is a patch in
4977 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4978 around this problem.
4982 GDB now supports array constants that can be used in expressions typed in by
4983 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4984 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4987 The new directory `gdb/sparclite' contains a program that demonstrates
4988 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4990 * New native hosts supported
4992 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4993 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4995 * New targets supported
4997 AMD 29k family via UDI a29k-amd-udi or udi29k
4999 * New file formats supported
5001 BFD now supports reading HP/PA-RISC executables (SOM file format?),
5002 HPUX core files, and SCO 3.2v2 core files.
5006 Attaching to processes now works again; thanks for the many bug reports.
5008 We have also stomped on a bunch of core dumps caused by
5009 printf_filtered("%s") problems.
5011 We eliminated a copyright problem on the rpc and ptrace header files
5012 for VxWorks, which was discovered at the last minute during the 4.7
5013 release. You should now be able to build a VxWorks GDB.
5015 You can now interrupt gdb while an attached process is running. This
5016 will cause the attached process to stop, and give control back to GDB.
5018 We fixed problems caused by using too many file descriptors
5019 for reading symbols from object files and libraries. This was
5020 especially a problem for programs that used many (~100) shared
5023 The `step' command now only enters a subroutine if there is line number
5024 information for the subroutine. Otherwise it acts like the `next'
5025 command. Previously, `step' would enter subroutines if there was
5026 any debugging information about the routine. This avoids problems
5027 when using `cc -g1' on MIPS machines.
5029 * Internal improvements
5031 GDB's internal interfaces have been improved to make it easier to support
5032 debugging of multiple languages in the future.
5034 GDB now uses a common structure for symbol information internally.
5035 Minimal symbols (derived from linkage symbols in object files), partial
5036 symbols (from a quick scan of debug information), and full symbols
5037 contain a common subset of information, making it easier to write
5038 shared code that handles any of them.
5040 * New command line options
5042 We now accept --silent as an alias for --quiet.
5046 The memory-mapped-malloc library is now licensed under the GNU Library
5047 General Public License.
5049 *** Changes in GDB-4.7:
5051 * Host/native/target split
5053 GDB has had some major internal surgery to untangle the support for
5054 hosts and remote targets. Now, when you configure GDB for a remote
5055 target, it will no longer load in all of the support for debugging
5056 local programs on the host. When fully completed and tested, this will
5057 ensure that arbitrary host/target combinations are possible.
5059 The primary conceptual shift is to separate the non-portable code in
5060 GDB into three categories. Host specific code is required any time GDB
5061 is compiled on that host, regardless of the target. Target specific
5062 code relates to the peculiarities of the target, but can be compiled on
5063 any host. Native specific code is everything else: it can only be
5064 built when the host and target are the same system. Child process
5065 handling and core file support are two common `native' examples.
5067 GDB's use of /proc for controlling Unix child processes is now cleaner.
5068 It has been split out into a single module under the `target_ops' vector,
5069 plus two native-dependent functions for each system that uses /proc.
5071 * New hosts supported
5073 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5074 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5075 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5077 * New targets supported
5079 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5080 68030 and CPU32 m68030-*-*, m68332-*-*
5082 * New native hosts supported
5084 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5085 (386bsd is not well tested yet)
5086 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5088 * New file formats supported
5090 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5091 supports reading of `a.out.adobe' object files, which are an a.out
5092 format extended with minimal information about multiple sections.
5096 `show copying' is the same as the old `info copying'.
5097 `show warranty' is the same as `info warrantee'.
5098 These were renamed for consistency. The old commands continue to work.
5100 `info handle' is a new alias for `info signals'.
5102 You can now define pre-command hooks, which attach arbitrary command
5103 scripts to any command. The commands in the hook will be executed
5104 prior to the user's command. You can also create a hook which will be
5105 executed whenever the program stops. See gdb.texinfo.
5109 We now deal with Cfront style name mangling, and can even extract type
5110 info from mangled symbols. GDB can automatically figure out which
5111 symbol mangling style your C++ compiler uses.
5113 Calling of methods and virtual functions has been improved as well.
5117 The crash that occured when debugging Sun Ansi-C compiled binaries is
5118 fixed. This was due to mishandling of the extra N_SO stabs output
5121 We also finally got Ultrix 4.2 running in house, and fixed core file
5122 support, with help from a dozen people on the net.
5124 John M. Farrell discovered that the reason that single-stepping was so
5125 slow on all of the Mips based platforms (primarily SGI and DEC) was
5126 that we were trying to demangle and lookup a symbol used for internal
5127 purposes on every instruction that was being stepped through. Changing
5128 the name of that symbol so that it couldn't be mistaken for a C++
5129 mangled symbol sped things up a great deal.
5131 Rich Pixley sped up symbol lookups in general by getting much smarter
5132 about when C++ symbol mangling is necessary. This should make symbol
5133 completion (TAB on the command line) much faster. It's not as fast as
5134 we'd like, but it's significantly faster than gdb-4.6.
5138 A new user controllable variable 'call_scratch_address' can
5139 specify the location of a scratch area to be used when GDB
5140 calls a function in the target. This is necessary because the
5141 usual method of putting the scratch area on the stack does not work
5142 in systems that have separate instruction and data spaces.
5144 We integrated changes to support the 29k UDI (Universal Debugger
5145 Interface), but discovered at the last minute that we didn't have all
5146 of the appropriate copyright paperwork. We are working with AMD to
5147 resolve this, and hope to have it available soon.
5151 We have sped up the remote serial line protocol, especially for targets
5152 with lots of registers. It now supports a new `expedited status' ('T')
5153 message which can be used in place of the existing 'S' status message.
5154 This allows the remote stub to send only the registers that GDB
5155 needs to make a quick decision about single-stepping or conditional
5156 breakpoints, eliminating the need to fetch the entire register set for
5157 each instruction being stepped through.
5159 The GDB remote serial protocol now implements a write-through cache for
5160 registers, only re-reading the registers if the target has run.
5162 There is also a new remote serial stub for SPARC processors. You can
5163 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5164 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5165 processor with a serial port.
5169 Configure.in files have become much easier to read and modify. A new
5170 `table driven' format makes it more obvious what configurations are
5171 supported, and what files each one uses.
5175 There is a new opcodes library which will eventually contain all of the
5176 disassembly routines and opcode tables. At present, it only contains
5177 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5178 disassembler (binutils/objdump) to share these routines.
5180 The libiberty library is now copylefted under the GNU Library General
5181 Public License. This allows more liberal use, and was done so libg++
5182 can use it. This makes no difference to GDB, since the Library License
5183 grants all the rights from the General Public License.
5187 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5188 reference to the stabs symbol info used by the debugger. It is (as far
5189 as we know) the only published document on this fascinating topic. We
5190 encourage you to read it, compare it to the stabs information on your
5191 system, and send improvements on the document in general (to
5192 bug-gdb@prep.ai.mit.edu).
5194 And, of course, many bugs have been fixed.
5197 *** Changes in GDB-4.6:
5199 * Better support for C++ function names
5201 GDB now accepts as input the "demangled form" of C++ overloaded function
5202 names and member function names, and can do command completion on such names
5203 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5204 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5205 Make use of command completion, it is your friend.
5207 GDB also now accepts a variety of C++ mangled symbol formats. They are
5208 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5209 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5210 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5211 for the list of formats.
5213 * G++ symbol mangling problem
5215 Recent versions of gcc have a bug in how they emit debugging information for
5216 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5217 directory) can be applied to gcc to fix the problem. Alternatively, if you
5218 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5219 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5220 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5223 * New 'maintenance' command
5225 All of the commands related to hacking GDB internals have been moved out of
5226 the main command set, and now live behind the 'maintenance' command. This
5227 can also be abbreviated as 'mt'. The following changes were made:
5229 dump-me -> maintenance dump-me
5230 info all-breakpoints -> maintenance info breakpoints
5231 printmsyms -> maintenance print msyms
5232 printobjfiles -> maintenance print objfiles
5233 printpsyms -> maintenance print psymbols
5234 printsyms -> maintenance print symbols
5236 The following commands are new:
5238 maintenance demangle Call internal GDB demangler routine to
5239 demangle a C++ link name and prints the result.
5240 maintenance print type Print a type chain for a given symbol
5242 * Change to .gdbinit file processing
5244 We now read the $HOME/.gdbinit file before processing the argv arguments
5245 (e.g. reading symbol files or core files). This allows global parameters to
5246 be set, which will apply during the symbol reading. The ./.gdbinit is still
5247 read after argv processing.
5249 * New hosts supported
5251 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5253 GNU/Linux support i386-unknown-linux or linux
5255 We are also including code to support the HP/PA running BSD and HPUX. This
5256 is almost guaranteed not to work, as we didn't have time to test or build it
5257 for this release. We are including it so that the more adventurous (or
5258 masochistic) of you can play with it. We also had major problems with the
5259 fact that the compiler that we got from HP doesn't support the -g option.
5262 * New targets supported
5264 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5266 * More smarts about finding #include files
5268 GDB now remembers the compilation directory for all include files, and for
5269 all files from which C is generated (like yacc and lex sources). This
5270 greatly improves GDB's ability to find yacc/lex sources, and include files,
5271 especially if you are debugging your program from a directory different from
5272 the one that contains your sources.
5274 We also fixed a bug which caused difficulty with listing and setting
5275 breakpoints in include files which contain C code. (In the past, you had to
5276 try twice in order to list an include file that you hadn't looked at before.)
5278 * Interesting infernals change
5280 GDB now deals with arbitrary numbers of sections, where the symbols for each
5281 section must be relocated relative to that section's landing place in the
5282 target's address space. This work was needed to support ELF with embedded
5283 stabs used by Solaris-2.0.
5285 * Bug fixes (of course!)
5287 There have been loads of fixes for the following things:
5288 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5289 i960, stabs, DOS(GO32), procfs, etc...
5291 See the ChangeLog for details.
5293 *** Changes in GDB-4.5:
5295 * New machines supported (host and target)
5297 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5299 SGI Irix-4.x mips-sgi-irix4 or iris4
5301 * New malloc package
5303 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5304 Mmalloc is capable of handling mutiple heaps of memory. It is also
5305 capable of saving a heap to a file, and then mapping it back in later.
5306 This can be used to greatly speedup the startup of GDB by using a
5307 pre-parsed symbol table which lives in a mmalloc managed heap. For
5308 more details, please read mmalloc/mmalloc.texi.
5312 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5313 'help info proc' for details.
5315 * MIPS ecoff symbol table format
5317 The code that reads MIPS symbol table format is now supported on all hosts.
5318 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5321 * File name changes for MS-DOS
5323 Many files in the config directories have been renamed to make it easier to
5324 support GDB on MS-DOSe systems (which have very restrictive file name
5325 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5326 environment) is close to working but has some remaining problems. Note
5327 that debugging of DOS programs is not supported, due to limitations
5328 in the ``operating system'', but it can be used to host cross-debugging.
5330 * Cross byte order fixes
5332 Many fixes have been made to support cross debugging of Sparc and MIPS
5333 targets from hosts whose byte order differs.
5335 * New -mapped and -readnow options
5337 If memory-mapped files are available on your system through the 'mmap'
5338 system call, you can use the -mapped option on the `file' or
5339 `symbol-file' commands to cause GDB to write the symbols from your
5340 program into a reusable file. If the program you are debugging is
5341 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5342 Future GDB debugging sessions will notice the presence of this file,
5343 and will quickly map in symbol information from it, rather than reading
5344 the symbol table from the executable program. Using the '-mapped'
5345 option in a GDB `file' or `symbol-file' command has the same effect as
5346 starting GDB with the '-mapped' command-line option.
5348 You can cause GDB to read the entire symbol table immediately by using
5349 the '-readnow' option with any of the commands that load symbol table
5350 information (or on the GDB command line). This makes the command
5351 slower, but makes future operations faster.
5353 The -mapped and -readnow options are typically combined in order to
5354 build a `fred.syms' file that contains complete symbol information.
5355 A simple GDB invocation to do nothing but build a `.syms' file for future
5358 gdb -batch -nx -mapped -readnow programname
5360 The `.syms' file is specific to the host machine on which GDB is run.
5361 It holds an exact image of GDB's internal symbol table. It cannot be
5362 shared across multiple host platforms.
5364 * longjmp() handling
5366 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5367 siglongjmp() without losing control. This feature has not yet been ported to
5368 all systems. It currently works on many 386 platforms, all MIPS-based
5369 platforms (SGI, DECstation, etc), and Sun3/4.
5373 Preliminary work has been put in to support the new Solaris OS from Sun. At
5374 this time, it can control and debug processes, but it is not capable of
5379 As always, many many bug fixes. The major areas were with g++, and mipsread.
5380 People using the MIPS-based platforms should experience fewer mysterious
5381 crashes and trashed symbol tables.
5383 *** Changes in GDB-4.4:
5385 * New machines supported (host and target)
5387 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5389 BSD Reno on Vax vax-dec-bsd
5390 Ultrix on Vax vax-dec-ultrix
5392 * New machines supported (target)
5394 AMD 29000 embedded, using EBMON a29k-none-none
5398 GDB continues to improve its handling of C++. `References' work better.
5399 The demangler has also been improved, and now deals with symbols mangled as
5400 per the Annotated C++ Reference Guide.
5402 GDB also now handles `stabs' symbol information embedded in MIPS
5403 `ecoff' symbol tables. Since the ecoff format was not easily
5404 extensible to handle new languages such as C++, this appeared to be a
5405 good way to put C++ debugging info into MIPS binaries. This option
5406 will be supported in the GNU C compiler, version 2, when it is
5409 * New features for SVR4
5411 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5412 shared libraries. Debugging dynamically linked programs should present
5413 only minor differences from debugging statically linked programs.
5415 The `info proc' command will print out information about any process
5416 on an SVR4 system (including the one you are debugging). At the moment,
5417 it prints the address mappings of the process.
5419 If you bring up GDB on another SVR4 system, please send mail to
5420 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5422 * Better dynamic linking support in SunOS
5424 Reading symbols from shared libraries which contain debugging symbols
5425 now works properly. However, there remain issues such as automatic
5426 skipping of `transfer vector' code during function calls, which
5427 make it harder to debug code in a shared library, than to debug the
5428 same code linked statically.
5432 GDB is now using the latest `getopt' routines from the FSF. This
5433 version accepts the -- prefix for options with long names. GDB will
5434 continue to accept the old forms (-option and +option) as well.
5435 Various single letter abbreviations for options have been explicity
5436 added to the option table so that they won't get overshadowed in the
5437 future by other options that begin with the same letter.
5441 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5442 Many assorted bugs have been handled. Many more remain to be handled.
5443 See the various ChangeLog files (primarily in gdb and bfd) for details.
5446 *** Changes in GDB-4.3:
5448 * New machines supported (host and target)
5450 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5451 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5452 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5454 * Almost SCO Unix support
5456 We had hoped to support:
5457 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5458 (except for core file support), but we discovered very late in the release
5459 that it has problems with process groups that render gdb unusable. Sorry
5460 about that. I encourage people to fix it and post the fixes.
5462 * Preliminary ELF and DWARF support
5464 GDB can read ELF object files on System V Release 4, and can handle
5465 debugging records for C, in DWARF format, in ELF files. This support
5466 is preliminary. If you bring up GDB on another SVR4 system, please
5467 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5472 GDB now uses the latest `readline' library. One user-visible change
5473 is that two tabs will list possible command completions, which previously
5474 required typing M-? (meta-question mark, or ESC ?).
5478 The `stepi' bug that many of you noticed has been squashed.
5479 Many bugs in C++ have been handled. Many more remain to be handled.
5480 See the various ChangeLog files (primarily in gdb and bfd) for details.
5482 * State of the MIPS world (in case you wondered):
5484 GDB can understand the symbol tables emitted by the compilers
5485 supplied by most vendors of MIPS-based machines, including DEC. These
5486 symbol tables are in a format that essentially nobody else uses.
5488 Some versions of gcc come with an assembler post-processor called
5489 mips-tfile. This program is required if you want to do source-level
5490 debugging of gcc-compiled programs. I believe FSF does not ship
5491 mips-tfile with gcc version 1, but it will eventually come with gcc
5494 Debugging of g++ output remains a problem. g++ version 1.xx does not
5495 really support it at all. (If you're lucky, you should be able to get
5496 line numbers and stack traces to work, but no parameters or local
5497 variables.) With some work it should be possible to improve the
5500 When gcc version 2 is released, you will have somewhat better luck.
5501 However, even then you will get confusing results for inheritance and
5504 We will eventually provide full debugging of g++ output on
5505 DECstations. This will probably involve some kind of stabs-in-ecoff
5506 encapulation, but the details have not been worked out yet.
5509 *** Changes in GDB-4.2:
5511 * Improved configuration
5513 Only one copy of `configure' exists now, and it is not self-modifying.
5514 Porting BFD is simpler.
5518 The `step' and `next' commands now only stop at the first instruction
5519 of a source line. This prevents the multiple stops that used to occur
5520 in switch statements, for-loops, etc. `Step' continues to stop if a
5521 function that has debugging information is called within the line.
5525 Lots of small bugs fixed. More remain.
5527 * New host supported (not target)
5529 Intel 386 PC clone running Mach i386-none-mach
5532 *** Changes in GDB-4.1:
5534 * Multiple source language support
5536 GDB now has internal scaffolding to handle several source languages.
5537 It determines the type of each source file from its filename extension,
5538 and will switch expression parsing and number formatting to match the
5539 language of the function in the currently selected stack frame.
5540 You can also specifically set the language to be used, with
5541 `set language c' or `set language modula-2'.
5545 GDB now has preliminary support for the GNU Modula-2 compiler,
5546 currently under development at the State University of New York at
5547 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5548 continue through the fall of 1991 and into 1992.
5550 Other Modula-2 compilers are currently not supported, and attempting to
5551 debug programs compiled with them will likely result in an error as the
5552 symbol table is read. Feel free to work on it, though!
5554 There are hooks in GDB for strict type checking and range checking,
5555 in the `Modula-2 philosophy', but they do not currently work.
5559 GDB can now write to executable and core files (e.g. patch
5560 a variable's value). You must turn this switch on, specify
5561 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5562 by assigning a new value to a variable. Modifications take
5565 * Automatic SunOS shared library reading
5567 When you run your program, GDB automatically determines where its
5568 shared libraries (if any) have been loaded, and reads their symbols.
5569 The `share' command is no longer needed. This also works when
5570 examining core files.
5574 You can specify the number of lines that the `list' command shows.
5577 * New machines supported (host and target)
5579 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5580 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5581 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5583 * New hosts supported (not targets)
5585 IBM RT/PC: romp-ibm-aix or rtpc
5587 * New targets supported (not hosts)
5589 AMD 29000 embedded with COFF a29k-none-coff
5590 AMD 29000 embedded with a.out a29k-none-aout
5591 Ultracomputer remote kernel debug a29k-nyu-kern
5593 * New remote interfaces
5599 *** Changes in GDB-4.0:
5603 Wide output is wrapped at good places to make the output more readable.
5605 Gdb now supports cross-debugging from a host machine of one type to a
5606 target machine of another type. Communication with the target system
5607 is over serial lines. The ``target'' command handles connecting to the
5608 remote system; the ``load'' command will download a program into the
5609 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5610 also supports debugging of realtime processes running under VxWorks,
5611 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5612 stub on the target system.
5614 New CPUs supported include the AMD 29000 and Intel 960.
5616 GDB now reads object files and symbol tables via a ``binary file''
5617 library, which allows a single copy of GDB to debug programs of multiple
5618 object file types such as a.out and coff.
5620 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5621 refcard.dvi and refcard.ps are available to format it).
5624 * Control-Variable user interface simplified
5626 All variables that control the operation of the debugger can be set
5627 by the ``set'' command, and displayed by the ``show'' command.
5629 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5630 ``Show prompt'' produces the response:
5631 Gdb's prompt is new-gdb=>.
5633 What follows are the NEW set commands. The command ``help set'' will
5634 print a complete list of old and new set commands. ``help set FOO''
5635 will give a longer description of the variable FOO. ``show'' will show
5636 all of the variable descriptions and their current settings.
5638 confirm on/off: Enables warning questions for operations that are
5639 hard to recover from, e.g. rerunning the program while
5640 it is already running. Default is ON.
5642 editing on/off: Enables EMACS style command line editing
5643 of input. Previous lines can be recalled with
5644 control-P, the current line can be edited with control-B,
5645 you can search for commands with control-R, etc.
5648 history filename NAME: NAME is where the gdb command history
5649 will be stored. The default is .gdb_history,
5650 or the value of the environment variable
5653 history size N: The size, in commands, of the command history. The
5654 default is 256, or the value of the environment variable
5657 history save on/off: If this value is set to ON, the history file will
5658 be saved after exiting gdb. If set to OFF, the
5659 file will not be saved. The default is OFF.
5661 history expansion on/off: If this value is set to ON, then csh-like
5662 history expansion will be performed on
5663 command line input. The default is OFF.
5665 radix N: Sets the default radix for input and output. It can be set
5666 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5667 in the current radix, so "set radix 10" is always a no-op.
5669 height N: This integer value is the number of lines on a page. Default
5670 is 24, the current `stty rows'' setting, or the ``li#''
5671 setting from the termcap entry matching the environment
5674 width N: This integer value is the number of characters on a line.
5675 Default is 80, the current `stty cols'' setting, or the ``co#''
5676 setting from the termcap entry matching the environment
5679 Note: ``set screensize'' is obsolete. Use ``set height'' and
5680 ``set width'' instead.
5682 print address on/off: Print memory addresses in various command displays,
5683 such as stack traces and structure values. Gdb looks
5684 more ``symbolic'' if you turn this off; it looks more
5685 ``machine level'' with it on. Default is ON.
5687 print array on/off: Prettyprint arrays. New convenient format! Default
5690 print demangle on/off: Print C++ symbols in "source" form if on,
5693 print asm-demangle on/off: Same, for assembler level printouts
5696 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5699 * Support for Epoch Environment.
5701 The epoch environment is a version of Emacs v18 with windowing. One
5702 new command, ``inspect'', is identical to ``print'', except that if you
5703 are running in the epoch environment, the value is printed in its own
5707 * Support for Shared Libraries
5709 GDB can now debug programs and core files that use SunOS shared libraries.
5710 Symbols from a shared library cannot be referenced
5711 before the shared library has been linked with the program (this
5712 happens after you type ``run'' and before the function main() is entered).
5713 At any time after this linking (including when examining core files
5714 from dynamically linked programs), gdb reads the symbols from each
5715 shared library when you type the ``sharedlibrary'' command.
5716 It can be abbreviated ``share''.
5718 sharedlibrary REGEXP: Load shared object library symbols for files
5719 matching a unix regular expression. No argument
5720 indicates to load symbols for all shared libraries.
5722 info sharedlibrary: Status of loaded shared libraries.
5727 A watchpoint stops execution of a program whenever the value of an
5728 expression changes. Checking for this slows down execution
5729 tremendously whenever you are in the scope of the expression, but is
5730 quite useful for catching tough ``bit-spreader'' or pointer misuse
5731 problems. Some machines such as the 386 have hardware for doing this
5732 more quickly, and future versions of gdb will use this hardware.
5734 watch EXP: Set a watchpoint (breakpoint) for an expression.
5736 info watchpoints: Information about your watchpoints.
5738 delete N: Deletes watchpoint number N (same as breakpoints).
5739 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5740 enable N: Re-enables watchpoint number N (same as breakpoints).
5743 * C++ multiple inheritance
5745 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5748 * C++ exception handling
5750 Gdb now supports limited C++ exception handling. Besides the existing
5751 ability to breakpoint on an exception handler, gdb can breakpoint on
5752 the raising of an exception (before the stack is peeled back to the
5755 catch FOO: If there is a FOO exception handler in the dynamic scope,
5756 set a breakpoint to catch exceptions which may be raised there.
5757 Multiple exceptions (``catch foo bar baz'') may be caught.
5759 info catch: Lists all exceptions which may be caught in the
5760 current stack frame.
5763 * Minor command changes
5765 The command ``call func (arg, arg, ...)'' now acts like the print
5766 command, except it does not print or save a value if the function's result
5767 is void. This is similar to dbx usage.
5769 The ``up'' and ``down'' commands now always print the frame they end up
5770 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5771 frames without printing.
5773 * New directory command
5775 'dir' now adds directories to the FRONT of the source search path.
5776 The path starts off empty. Source files that contain debug information
5777 about the directory in which they were compiled can be found even
5778 with an empty path; Sun CC and GCC include this information. If GDB can't
5779 find your source file in the current directory, type "dir .".
5781 * Configuring GDB for compilation
5783 For normal use, type ``./configure host''. See README or gdb.texinfo
5786 GDB now handles cross debugging. If you are remotely debugging between
5787 two different machines, type ``./configure host -target=targ''.
5788 Host is the machine where GDB will run; targ is the machine
5789 where the program that you are debugging will run.