1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * New command line options
9 This is an alias for the --data-directory option.
11 * GDB supports printing and modifying of variable length automatic arrays
12 as specified in ISO C99.
14 * The ARM simulator now supports instruction level tracing
15 with or without disassembly.
19 GDB now has support for scripting using Guile. Whether this is
20 available is determined at configure time.
21 Guile version 2.0 or greater is required.
22 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
24 * New commands (for set/show, see "New options" below)
28 Invoke CODE by passing it to the Guile interpreter.
32 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
34 info auto-load guile-scripts [regexp]
35 Print the list of automatically loaded Guile scripts.
37 * The source command is now capable of sourcing Guile scripts.
38 This feature is dependent on the debugger being built with Guile support.
42 set print symbol-loading (off|brief|full)
43 show print symbol-loading
44 Control whether to print informational messages when loading symbol
45 information for a file. The default is "full", but when debugging
46 programs with large numbers of shared libraries the amount of output
49 set guile print-stack (none|message|full)
50 show guile print-stack
51 Show a stack trace when an error is encountered in a Guile script.
53 set auto-load guile-scripts (on|off)
54 show auto-load guile-scripts
55 Control auto-loading of Guile script files.
57 maint ada set ignore-descriptive-types (on|off)
58 maint ada show ignore-descriptive-types
59 Control whether the debugger should ignore descriptive types in Ada
60 programs. The default is not to ignore the descriptive types. See
61 the user manual for more details on descriptive types and the intended
64 * New features in the GDB remote stub, GDBserver
66 ** New option --debug-format=option1[,option2,...] allows one to add
67 additional text to each output. At present only timestamps
68 are supported: --debug-format=timestamps.
69 Timestamps can also be turned on with the
70 "monitor set debug-format timestamps" command from GDB.
72 * The 'record instruction-history' command now starts counting instructions
73 at one. This also affects the instruction ranges reported by the
74 'record function-call-history' command when given the /i modifier.
76 * The command 'record function-call-history' supports a new modifier '/c' to
77 indent the function names based on their call stack depth.
78 The fields for the '/i' and '/l' modifier have been reordered.
79 The source line range is now prefixed with 'at'.
80 The instruction range is now prefixed with 'inst'.
81 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
82 "record instruction-history" and "list" commands.
84 * The ranges given as arguments to the 'record function-call-history' and
85 'record instruction-history' commands are now inclusive.
87 * The btrace record target now supports the 'record goto' command.
88 For locations inside the execution trace, the back trace is computed
89 based on the information stored in the execution trace.
91 * The btrace record target supports limited reverse execution and replay.
92 The target does not record data and therefore does not allow reading
95 * The "catch syscall" command now works on s390*-linux* targets.
99 qXfer:btrace:read's annex
100 The qXfer:btrace:read packet supports a new annex 'delta' to read
101 branch trace incrementally.
105 ** Valid Python operations on gdb.Value objects representing
106 structs/classes invoke the corresponding overloaded operators if
110 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
112 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
113 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
114 its alias "share", instead.
116 *** Changes in GDB 7.7
118 * Improved support for process record-replay and reverse debugging on
119 arm*-linux* targets. Support for thumb32 and syscall instruction
120 recording has been added.
122 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
124 * GDB now supports Fission DWP file format version 2.
125 http://gcc.gnu.org/wiki/DebugFission
127 * New convenience function "$_isvoid", to check whether an expression
128 is void. A void expression is an expression where the type of the
129 result is "void". For example, some convenience variables may be
130 "void" when evaluated (e.g., "$_exitcode" before the execution of
131 the program being debugged; or an undefined convenience variable).
132 Another example, when calling a function whose return type is
135 * The "maintenance print objfiles" command now takes an optional regexp.
137 * The "catch syscall" command now works on arm*-linux* targets.
139 * GDB now consistently shows "<not saved>" when printing values of
140 registers the debug info indicates have not been saved in the frame
141 and there's nowhere to retrieve them from
142 (callee-saved/call-clobbered registers):
147 (gdb) info registers rax
150 Before, the former would print "<optimized out>", and the latter
151 "*value not available*".
153 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
158 ** Frame filters and frame decorators have been added.
159 ** Temporary breakpoints are now supported.
160 ** Line tables representation has been added.
161 ** New attribute 'parent_type' for gdb.Field objects.
162 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
163 ** New attribute 'name' for gdb.Type objects.
167 Nios II ELF nios2*-*-elf
168 Nios II GNU/Linux nios2*-*-linux
169 Texas Instruments MSP430 msp430*-*-elf
171 * Removed native configurations
173 Support for these a.out NetBSD and OpenBSD obsolete configurations has
174 been removed. ELF variants of these configurations are kept supported.
176 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
177 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
178 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
179 i[34567]86-*-openbsd3.[0-3]
180 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
181 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
182 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
186 Like "catch throw", but catches a re-thrown exception.
188 Renamed from old "maint check-symtabs".
190 Perform consistency checks on symtabs.
192 Expand symtabs matching an optional regexp.
195 Display the details of GDB configure-time options.
197 maint set|show per-command
198 maint set|show per-command space
199 maint set|show per-command time
200 maint set|show per-command symtab
201 Enable display of per-command gdb resource usage.
203 remove-symbol-file FILENAME
204 remove-symbol-file -a ADDRESS
205 Remove a symbol file added via add-symbol-file. The file to remove
206 can be identified by its filename or by an address that lies within
207 the boundaries of this symbol file in memory.
210 info exceptions REGEXP
211 Display the list of Ada exceptions defined in the program being
212 debugged. If provided, only the exceptions whose names match REGEXP
217 set debug symfile off|on
219 Control display of debugging info regarding reading symbol files and
220 symbol tables within those files
222 set print raw frame-arguments
223 show print raw frame-arguments
224 Set/show whether to print frame arguments in raw mode,
225 disregarding any defined pretty-printers.
227 set remote trace-status-packet
228 show remote trace-status-packet
229 Set/show the use of remote protocol qTStatus packet.
233 Control display of debugging messages related to Nios II targets.
237 Control whether target-assisted range stepping is enabled.
239 set startup-with-shell
240 show startup-with-shell
241 Specifies whether Unix child processes are started via a shell or
246 Use the target memory cache for accesses to the code segment. This
247 improves performance of remote debugging (particularly disassembly).
249 * You can now use a literal value 'unlimited' for options that
250 interpret 0 or -1 as meaning "unlimited". E.g., "set
251 trace-buffer-size unlimited" is now an alias for "set
252 trace-buffer-size -1" and "set height unlimited" is now an alias for
255 * The "set debug symtab-create" debugging option of GDB has been changed to
256 accept a verbosity level. 0 means "off", 1 provides basic debugging
257 output, and values of 2 or greater provides more verbose output.
259 * New command-line options
261 Display the details of GDB configure-time options.
263 * The command 'tsave' can now support new option '-ctf' to save trace
264 buffer in Common Trace Format.
266 * Newly installed $prefix/bin/gcore acts as a shell interface for the
269 * GDB now implements the the C++ 'typeid' operator.
271 * The new convenience variable $_exception holds the exception being
272 thrown or caught at an exception-related catchpoint.
274 * The exception-related catchpoints, like "catch throw", now accept a
275 regular expression which can be used to filter exceptions by type.
277 * The new convenience variable $_exitsignal is automatically set to
278 the terminating signal number when the program being debugged dies
279 due to an uncaught signal.
283 ** All MI commands now accept an optional "--language" option.
284 Support for this feature can be verified by using the "-list-features"
285 command, which should contain "language-option".
287 ** The new command -info-gdb-mi-command allows the user to determine
288 whether a GDB/MI command is supported or not.
290 ** The "^error" result record returned when trying to execute an undefined
291 GDB/MI command now provides a variable named "code" whose content is the
292 "undefined-command" error code. Support for this feature can be verified
293 by using the "-list-features" command, which should contain
294 "undefined-command-error-code".
296 ** The -trace-save MI command can optionally save trace buffer in Common
299 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
301 ** The command -data-list-register-values now accepts an optional
302 "--skip-unavailable" option. When used, only the available registers
305 ** The new command -trace-frame-collected dumps collected variables,
306 computed expressions, tvars, memory and registers in a traceframe.
308 ** The commands -stack-list-locals, -stack-list-arguments and
309 -stack-list-variables now accept an option "--skip-unavailable".
310 When used, only the available locals or arguments are displayed.
312 ** The -exec-run command now accepts an optional "--start" option.
313 When used, the command follows the same semantics as the "start"
314 command, stopping the program's execution at the start of its
315 main subprogram. Support for this feature can be verified using
316 the "-list-features" command, which should contain
317 "exec-run-start-option".
319 ** The new commands -catch-assert and -catch-exceptions insert
320 catchpoints stopping the program when Ada exceptions are raised.
322 ** The new command -info-ada-exceptions provides the equivalent of
323 the new "info exceptions" command.
325 * New system-wide configuration scripts
326 A GDB installation now provides scripts suitable for use as system-wide
327 configuration scripts for the following systems:
331 * GDB now supports target-assigned range stepping with remote targets.
332 This improves the performance of stepping source lines by reducing
333 the number of control packets from/to GDB. See "New remote packets"
336 * GDB now understands the element 'tvar' in the XML traceframe info.
337 It has the id of the collected trace state variables.
339 * On S/390 targets that provide the transactional-execution feature,
340 the program interruption transaction diagnostic block (TDB) is now
341 represented as a number of additional "registers" in GDB.
347 The vCont packet supports a new 'r' action, that tells the remote
348 stub to step through an address range itself, without GDB
349 involvemement at each single-step.
351 qXfer:libraries-svr4:read's annex
352 The previously unused annex of the qXfer:libraries-svr4:read packet
353 is now used to support passing an argument list. The remote stub
354 reports support for this argument list to GDB's qSupported query.
355 The defined arguments are "start" and "prev", used to reduce work
356 necessary for library list updating, resulting in significant
359 * New features in the GDB remote stub, GDBserver
361 ** GDBserver now supports target-assisted range stepping. Currently
362 enabled on x86/x86_64 GNU/Linux targets.
364 ** GDBserver now adds element 'tvar' in the XML in the reply to
365 'qXfer:traceframe-info:read'. It has the id of the collected
366 trace state variables.
368 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
371 * New 'z' formatter for printing and examining memory, this displays the
372 value as hexadecimal zero padded on the left to the size of the type.
374 * GDB can now use Windows x64 unwinding data.
376 * The "set remotebaud" command has been replaced by "set serial baud".
377 Similarly, "show remotebaud" has been replaced by "show serial baud".
378 The "set remotebaud" and "show remotebaud" commands are still available
379 to provide backward compatibility with older versions of GDB.
381 *** Changes in GDB 7.6
383 * Target record has been renamed to record-full.
384 Record/replay is now enabled with the "record full" command.
385 This also affects settings that are associated with full record/replay
386 that have been moved from "set/show record" to "set/show record full":
388 set|show record full insn-number-max
389 set|show record full stop-at-limit
390 set|show record full memory-query
392 * A new record target "record-btrace" has been added. The new target
393 uses hardware support to record the control-flow of a process. It
394 does not support replaying the execution, but it implements the
395 below new commands for investigating the recorded execution log.
396 This new recording method can be enabled using:
400 The "record-btrace" target is only available on Intel Atom processors
401 and requires a Linux kernel 2.6.32 or later.
403 * Two new commands have been added for record/replay to give information
404 about the recorded execution without having to replay the execution.
405 The commands are only supported by "record btrace".
407 record instruction-history prints the execution history at
408 instruction granularity
410 record function-call-history prints the execution history at
413 * New native configurations
415 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
416 FreeBSD/powerpc powerpc*-*-freebsd
417 x86_64/Cygwin x86_64-*-cygwin*
418 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
422 ARM AArch64 aarch64*-*-elf
423 ARM AArch64 GNU/Linux aarch64*-*-linux
424 Lynx 178 PowerPC powerpc-*-lynx*178
425 x86_64/Cygwin x86_64-*-cygwin*
426 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
428 * If the configured location of system.gdbinit file (as given by the
429 --with-system-gdbinit option at configure time) is in the
430 data-directory (as specified by --with-gdb-datadir at configure
431 time) or in one of its subdirectories, then GDB will look for the
432 system-wide init file in the directory specified by the
433 --data-directory command-line option.
435 * New command line options:
437 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
438 other initialization files, unlike -nx which disables all of them.
440 * Removed command line options
442 -epoch This was used by the gdb mode in Epoch, an ancient fork of
445 * The 'ptype' and 'whatis' commands now accept an argument to control
448 * 'info proc' now works on some core files.
452 ** Vectors can be created with gdb.Type.vector.
454 ** Python's atexit.register now works in GDB.
456 ** Types can be pretty-printed via a Python API.
458 ** Python 3 is now supported (in addition to Python 2.4 or later)
460 ** New class gdb.Architecture exposes GDB's internal representation
461 of architecture in the Python API.
463 ** New method Frame.architecture returns the gdb.Architecture object
464 corresponding to the frame's architecture.
466 * New Python-based convenience functions:
468 ** $_memeq(buf1, buf2, length)
469 ** $_streq(str1, str2)
471 ** $_regex(str, regex)
473 * The 'cd' command now defaults to using '~' (the home directory) if not
476 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
477 default for GCC since November 2000.
479 * The command 'forward-search' can now be abbreviated as 'fo'.
481 * The command 'info tracepoints' can now display 'installed on target'
482 or 'not installed on target' for each non-pending location of tracepoint.
484 * New configure options
486 --enable-libmcheck/--disable-libmcheck
487 By default, development versions are built with -lmcheck on hosts
488 that support it, in order to help track memory corruption issues.
489 Release versions, on the other hand, are built without -lmcheck
490 by default. The --enable-libmcheck/--disable-libmcheck configure
491 options allow the user to override that default.
492 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
493 This configure option allows the user to build GDB with
494 libbabeltrace using which GDB can read Common Trace Format data.
496 * New commands (for set/show, see "New options" below)
499 Catch signals. This is similar to "handle", but allows commands and
500 conditions to be attached.
503 List the BFDs known to GDB.
505 python-interactive [command]
507 Start a Python interactive prompt, or evaluate the optional command
508 and print the result of expressions.
511 "py" is a new alias for "python".
513 enable type-printer [name]...
514 disable type-printer [name]...
515 Enable or disable type printers.
519 ** For the Renesas Super-H architecture, the "regs" command has been removed
520 (has been deprecated in GDB 7.5), and "info all-registers" should be used
525 set print type methods (on|off)
526 show print type methods
527 Control whether method declarations are displayed by "ptype".
528 The default is to show them.
530 set print type typedefs (on|off)
531 show print type typedefs
532 Control whether typedef definitions are displayed by "ptype".
533 The default is to show them.
535 set filename-display basename|relative|absolute
536 show filename-display
537 Control the way in which filenames is displayed.
538 The default is "relative", which preserves previous behavior.
540 set trace-buffer-size
541 show trace-buffer-size
542 Request target to change the size of trace buffer.
544 set remote trace-buffer-size-packet auto|on|off
545 show remote trace-buffer-size-packet
546 Control the use of the remote protocol `QTBuffer:size' packet.
550 Control display of debugging messages related to ARM AArch64.
553 set debug coff-pe-read
554 show debug coff-pe-read
555 Control display of debugging messages related to reading of COFF/PE
560 Control display of debugging messages related to Mach-O symbols
563 set debug notification
564 show debug notification
565 Control display of debugging info for async remote notification.
569 ** Command parameter changes are now notified using new async record
570 "=cmd-param-changed".
571 ** Trace frame changes caused by command "tfind" are now notified using
572 new async record "=traceframe-changed".
573 ** The creation, deletion and modification of trace state variables
574 are now notified using new async records "=tsv-created",
575 "=tsv-deleted" and "=tsv-modified".
576 ** The start and stop of process record are now notified using new
577 async record "=record-started" and "=record-stopped".
578 ** Memory changes are now notified using new async record
580 ** The data-disassemble command response will include a "fullname" field
581 containing the absolute file name when source has been requested.
582 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
583 command, to allow pattern filling of memory areas.
584 ** New commands "-catch-load"/"-catch-unload" added for intercepting
585 library load/unload events.
586 ** The response to breakpoint commands and breakpoint async records
587 includes an "installed" field containing a boolean state about each
588 non-pending tracepoint location is whether installed on target or not.
589 ** Output of the "-trace-status" command includes a "trace-file" field
590 containing the name of the trace file being examined. This field is
591 optional, and only present when examining a trace file.
592 ** The "fullname" field is now always present along with the "file" field,
593 even if the file cannot be found by GDB.
595 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
596 You must have the LZMA library available when configuring GDB for this
597 feature to be enabled. For more information, see:
598 http://fedoraproject.org/wiki/Features/MiniDebugInfo
603 Set the size of trace buffer. The remote stub reports support for this
604 packet to gdb's qSupported query.
607 Enable Branch Trace Store (BTS)-based branch tracing for the current
608 thread. The remote stub reports support for this packet to gdb's
612 Disable branch tracing for the current thread. The remote stub reports
613 support for this packet to gdb's qSupported query.
616 Read the traced branches for the current thread. The remote stub
617 reports support for this packet to gdb's qSupported query.
619 *** Changes in GDB 7.5
621 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
622 for more x32 ABI info.
624 * GDB now supports access to MIPS DSP registers on Linux targets.
626 * GDB now supports debugging microMIPS binaries.
628 * The "info os" command on GNU/Linux can now display information on
629 several new classes of objects managed by the operating system:
630 "info os procgroups" lists process groups
631 "info os files" lists file descriptors
632 "info os sockets" lists internet-domain sockets
633 "info os shm" lists shared-memory regions
634 "info os semaphores" lists semaphores
635 "info os msg" lists message queues
636 "info os modules" lists loaded kernel modules
638 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
639 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
640 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
641 options and inspect the probe arguments using the new $_probe_arg family
642 of convenience variables. You can obtain more information about SystemTap
643 in <http://sourceware.org/systemtap/>.
645 * GDB now supports reversible debugging on ARM, it allows you to
646 debug basic ARM and THUMB instructions, and provides
647 record/replay support.
649 * The option "symbol-reloading" has been deleted as it is no longer used.
653 ** GDB commands implemented in Python can now be put in command class
656 ** The "maint set python print-stack on|off" is now deleted.
658 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
659 apply "flag enum"-style pretty-printing to any enum.
661 ** gdb.lookup_symbol can now work when there is no current frame.
663 ** gdb.Symbol now has a 'line' attribute, holding the line number in
664 the source at which the symbol was defined.
666 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
667 method 'value'. The former indicates whether the symbol needs a
668 frame in order to compute its value, and the latter computes the
671 ** A new method 'referenced_value' on gdb.Value objects which can
672 dereference pointer as well as C++ reference values.
674 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
675 which return the global and static blocks (as gdb.Block objects),
676 of the underlying symbol table, respectively.
678 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
679 object associated with a PC value.
681 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
682 of the address range occupied by code for the current source line.
684 * Go language support.
685 GDB now supports debugging programs written in the Go programming
688 * GDBserver now supports stdio connections.
689 E.g. (gdb) target remote | ssh myhost gdbserver - hello
691 * The binary "gdbtui" can no longer be built or installed.
692 Use "gdb -tui" instead.
694 * GDB will now print "flag" enums specially. A flag enum is one where
695 all the enumerator values have no bits in common when pairwise
696 "and"ed. When printing a value whose type is a flag enum, GDB will
697 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
698 (gdb) print (enum E) 3
701 * The filename part of a linespec will now match trailing components
702 of a source file name. For example, "break gcc/expr.c:1000" will
703 now set a breakpoint in build/gcc/expr.c, but not
706 * The "info proc" and "generate-core-file" commands will now also
707 work on remote targets connected to GDBserver on Linux.
709 * The command "info catch" has been removed. It has been disabled
712 * The "catch exception" and "catch assert" commands now accept
713 a condition at the end of the command, much like the "break"
714 command does. For instance:
716 (gdb) catch exception Constraint_Error if Barrier = True
718 Previously, it was possible to add a condition to such catchpoints,
719 but it had to be done as a second step, after the catchpoint had been
720 created, using the "condition" command.
722 * The "info static-tracepoint-marker" command will now also work on
723 native Linux targets with in-process agent.
725 * GDB can now set breakpoints on inlined functions.
727 * The .gdb_index section has been updated to include symbols for
728 inlined functions. GDB will ignore older .gdb_index sections by
729 default, which could cause symbol files to be loaded more slowly
730 until their .gdb_index sections can be recreated. The new command
731 "set use-deprecated-index-sections on" will cause GDB to use any older
732 .gdb_index sections it finds. This will restore performance, but the
733 ability to set breakpoints on inlined functions will be lost in symbol
734 files with older .gdb_index sections.
736 The .gdb_index section has also been updated to record more information
737 about each symbol. This speeds up the "info variables", "info functions"
738 and "info types" commands when used with programs having the .gdb_index
739 section, as well as speeding up debugging with shared libraries using
740 the .gdb_index section.
742 * Ada support for GDB/MI Variable Objects has been added.
744 * GDB can now support 'breakpoint always-inserted mode' in 'record'
749 ** New command -info-os is the MI equivalent of "info os".
751 ** Output logs ("set logging" and related) now include MI output.
755 ** "set use-deprecated-index-sections on|off"
756 "show use-deprecated-index-sections on|off"
757 Controls the use of deprecated .gdb_index sections.
759 ** "catch load" and "catch unload" can be used to stop when a shared
760 library is loaded or unloaded, respectively.
762 ** "enable count" can be used to auto-disable a breakpoint after
765 ** "info vtbl" can be used to show the virtual method tables for
766 C++ and Java objects.
768 ** "explore" and its sub commands "explore value" and "explore type"
769 can be used to recursively explore values and types of
770 expressions. These commands are available only if GDB is
771 configured with '--with-python'.
773 ** "info auto-load" shows status of all kinds of auto-loaded files,
774 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
775 sequences of commands files, "info auto-load python-scripts"
776 shows status of auto-loading Python script files,
777 "info auto-load local-gdbinit" shows status of loading init file
778 (.gdbinit) from current directory and "info auto-load libthread-db" shows
779 status of inferior specific thread debugging shared library loading.
781 ** "info auto-load-scripts", "set auto-load-scripts on|off"
782 and "show auto-load-scripts" commands have been deprecated, use their
783 "info auto-load python-scripts", "set auto-load python-scripts on|off"
784 and "show auto-load python-scripts" counterparts instead.
786 ** "dprintf location,format,args..." creates a dynamic printf, which
787 is basically a breakpoint that does a printf and immediately
788 resumes your program's execution, so it is like a printf that you
789 can insert dynamically at runtime instead of at compiletime.
791 ** "set print symbol"
793 Controls whether GDB attempts to display the symbol, if any,
794 corresponding to addresses it prints. This defaults to "on", but
795 you can set it to "off" to restore GDB's previous behavior.
797 * Deprecated commands
799 ** For the Renesas Super-H architecture, the "regs" command has been
800 deprecated, and "info all-registers" should be used instead.
804 Renesas RL78 rl78-*-elf
805 HP OpenVMS ia64 ia64-hp-openvms*
807 * GDBserver supports evaluation of breakpoint conditions. When
808 support is advertised by GDBserver, GDB may be told to send the
809 breakpoint conditions in bytecode form to GDBserver. GDBserver
810 will only report the breakpoint trigger to GDB when its condition
816 show mips compression
817 Select the compressed ISA encoding used in functions that have no symbol
818 information available. The encoding can be set to either of:
821 and is updated automatically from ELF file flags if available.
823 set breakpoint condition-evaluation
824 show breakpoint condition-evaluation
825 Control whether breakpoint conditions are evaluated by GDB ("host") or by
826 GDBserver ("target"). Default option "auto" chooses the most efficient
828 This option can improve debugger efficiency depending on the speed of the
832 Disable auto-loading globally.
835 Show auto-loading setting of all kinds of auto-loaded files.
837 set auto-load gdb-scripts on|off
838 show auto-load gdb-scripts
839 Control auto-loading of GDB canned sequences of commands files.
841 set auto-load python-scripts on|off
842 show auto-load python-scripts
843 Control auto-loading of Python script files.
845 set auto-load local-gdbinit on|off
846 show auto-load local-gdbinit
847 Control loading of init file (.gdbinit) from current directory.
849 set auto-load libthread-db on|off
850 show auto-load libthread-db
851 Control auto-loading of inferior specific thread debugging shared library.
853 set auto-load scripts-directory <dir1>[:<dir2>...]
854 show auto-load scripts-directory
855 Set a list of directories from which to load auto-loaded scripts.
856 Automatically loaded Python scripts and GDB scripts are located in one
857 of the directories listed by this option.
858 The delimiter (':' above) may differ according to the host platform.
860 set auto-load safe-path <dir1>[:<dir2>...]
861 show auto-load safe-path
862 Set a list of directories from which it is safe to auto-load files.
863 The delimiter (':' above) may differ according to the host platform.
865 set debug auto-load on|off
867 Control display of debugging info for auto-loading the files above.
869 set dprintf-style gdb|call|agent
871 Control the way in which a dynamic printf is performed; "gdb"
872 requests a GDB printf command, while "call" causes dprintf to call a
873 function in the inferior. "agent" requests that the target agent
874 (such as GDBserver) do the printing.
876 set dprintf-function <expr>
877 show dprintf-function
878 set dprintf-channel <expr>
880 Set the function and optional first argument to the call when using
881 the "call" style of dynamic printf.
883 set disconnected-dprintf on|off
884 show disconnected-dprintf
885 Control whether agent-style dynamic printfs continue to be in effect
886 after GDB disconnects.
888 * New configure options
891 Configure default value for the 'set auto-load scripts-directory'
892 setting above. It defaults to '$debugdir:$datadir/auto-load',
893 $debugdir representing global debugging info directories (available
894 via 'show debug-file-directory') and $datadir representing GDB's data
895 directory (available via 'show data-directory').
897 --with-auto-load-safe-path
898 Configure default value for the 'set auto-load safe-path' setting
899 above. It defaults to the --with-auto-load-dir setting.
901 --without-auto-load-safe-path
902 Set 'set auto-load safe-path' to '/', effectively disabling this
907 z0/z1 conditional breakpoints extension
909 The z0/z1 breakpoint insertion packets have been extended to carry
910 a list of conditional expressions over to the remote stub depending on the
911 condition evaluation mode. The use of this extension can be controlled
912 via the "set remote conditional-breakpoints-packet" command.
916 Specify the signals which the remote stub may pass to the debugged
917 program without GDB involvement.
919 * New command line options
921 --init-command=FILE, -ix Like --command, -x but execute it
922 before loading inferior.
923 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
924 execute it before loading inferior.
926 *** Changes in GDB 7.4
928 * GDB now handles ambiguous linespecs more consistently; the existing
929 FILE:LINE support has been expanded to other types of linespecs. A
930 breakpoint will now be set on all matching locations in all
931 inferiors, and locations will be added or removed according to
934 * GDB now allows you to skip uninteresting functions and files when
935 stepping with the "skip function" and "skip file" commands.
937 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
938 and "show remote hardware-watchpoint-length-limit". These allows to
939 set or show the maximum length limit (in bytes) of a remote
940 target hardware watchpoint.
942 This allows e.g. to use "unlimited" hardware watchpoints with the
943 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
944 watchpoints are slower than real hardware watchpoints but are
945 significantly faster than gdb software watchpoints.
949 ** The register_pretty_printer function in module gdb.printing now takes
950 an optional `replace' argument. If True, the new printer replaces any
953 ** The "maint set python print-stack on|off" command has been
954 deprecated and will be deleted in GDB 7.5.
955 A new command: "set python print-stack none|full|message" has
956 replaced it. Additionally, the default for "print-stack" is
957 now "message", which just prints the error message without
960 ** A prompt substitution hook (prompt_hook) is now available to the
963 ** A new Python module, gdb.prompt has been added to the GDB Python
964 modules library. This module provides functionality for
965 escape sequences in prompts (used by set/show
966 extended-prompt). These escape sequences are replaced by their
969 ** Python commands and convenience-functions located in
970 'data-directory'/python/gdb/command and
971 'data-directory'/python/gdb/function are now automatically loaded
974 ** Blocks now provide four new attributes. global_block and
975 static_block will return the global and static blocks
976 respectively. is_static and is_global are boolean attributes
977 that indicate if the block is one of those two types.
979 ** Symbols now provide the "type" attribute, the type of the symbol.
981 ** The "gdb.breakpoint" function has been deprecated in favor of
984 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
985 of a function. This class is based on the "finish" command
986 available in the CLI.
988 ** Type objects for struct and union types now allow access to
989 the fields using standard Python dictionary (mapping) methods.
990 For example, "some_type['myfield']" now works, as does
993 ** A new event "gdb.new_objfile" has been added, triggered by loading a
996 ** A new function, "deep_items" has been added to the gdb.types
997 module in the GDB Python modules library. This function returns
998 an iterator over the fields of a struct or union type. Unlike
999 the standard Python "iteritems" method, it will recursively traverse
1000 any anonymous fields.
1004 ** "*stopped" events can report several new "reason"s, such as
1007 ** Breakpoint changes are now notified using new async records, like
1008 "=breakpoint-modified".
1010 ** New command -ada-task-info.
1012 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1013 $sdir specifies the default system locations of shared libraries.
1014 $pdir specifies the directory where the libpthread used by the application
1017 GDB no longer looks in $sdir and $pdir after it has searched the directories
1018 mentioned in libthread-db-search-path. If you want to search those
1019 directories, they must be specified in libthread-db-search-path.
1020 The default value of libthread-db-search-path on GNU/Linux and Solaris
1021 systems is now "$sdir:$pdir".
1023 $pdir is not supported by gdbserver, it is currently ignored.
1024 $sdir is supported by gdbserver.
1026 * New configure option --with-iconv-bin.
1027 When using the internationalization support like the one in the GNU C
1028 library, GDB will invoke the "iconv" program to get a list of supported
1029 character sets. If this program lives in a non-standard location, one can
1030 use this option to specify where to find it.
1032 * When natively debugging programs on PowerPC BookE processors running
1033 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1034 watchpoints, which specify a mask in addition to an address to watch.
1035 The mask specifies that some bits of an address (the bits which are
1036 reset in the mask) should be ignored when matching the address accessed
1037 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1038 section in the user manual for more details.
1040 * The new option --once causes GDBserver to stop listening for connections once
1041 the first connection is made. The listening port used by GDBserver will
1042 become available after that.
1044 * New commands "info macros" and "alias" have been added.
1046 * New function parameters suffix @entry specifies value of function parameter
1047 at the time the function got called. Entry values are available only since
1053 "!" is now an alias of the "shell" command.
1054 Note that no space is needed between "!" and SHELL COMMAND.
1058 watch EXPRESSION mask MASK_VALUE
1059 The watch command now supports the mask argument which allows creation
1060 of masked watchpoints, if the current architecture supports this feature.
1062 info auto-load-scripts [REGEXP]
1063 This command was formerly named "maintenance print section-scripts".
1064 It is now generally useful and is no longer a maintenance-only command.
1066 info macro [-all] [--] MACRO
1067 The info macro command has new options `-all' and `--'. The first for
1068 printing all definitions of a macro. The second for explicitly specifying
1069 the end of arguments and the beginning of the macro name in case the macro
1070 name starts with a hyphen.
1072 collect[/s] EXPRESSIONS
1073 The tracepoint collect command now takes an optional modifier "/s"
1074 that directs it to dereference pointer-to-character types and
1075 collect the bytes of memory up to a zero byte. The behavior is
1076 similar to what you see when you use the regular print command on a
1077 string. An optional integer following the "/s" sets a bound on the
1078 number of bytes that will be collected.
1081 The trace start command now interprets any supplied arguments as a
1082 note to be recorded with the trace run, with an effect similar to
1083 setting the variable trace-notes.
1086 The trace stop command now interprets any arguments as a note to be
1087 mentioned along with the tstatus report that the trace was stopped
1088 with a command. The effect is similar to setting the variable
1091 * Tracepoints can now be enabled and disabled at any time after a trace
1092 experiment has been started using the standard "enable" and "disable"
1093 commands. It is now possible to start a trace experiment with no enabled
1094 tracepoints; GDB will display a warning, but will allow the experiment to
1095 begin, assuming that tracepoints will be enabled as needed while the trace
1098 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1099 locations with 4-byte instructions, when they were previously
1100 limited to locations with instructions of 5 bytes or longer.
1104 set debug dwarf2-read
1105 show debug dwarf2-read
1106 Turns on or off display of debugging messages related to reading
1107 DWARF debug info. The default is off.
1109 set debug symtab-create
1110 show debug symtab-create
1111 Turns on or off display of debugging messages related to symbol table
1112 creation. The default is off.
1115 show extended-prompt
1116 Set the GDB prompt, and allow escape sequences to be inserted to
1117 display miscellaneous information (see 'help set extended-prompt'
1118 for the list of sequences). This prompt (and any information
1119 accessed through the escape sequences) is updated every time the
1120 prompt is displayed.
1122 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1123 show print entry-values
1124 Set printing of frame argument values at function entry. In some cases
1125 GDB can determine the value of function argument which was passed by the
1126 function caller, even if the value was modified inside the called function.
1128 set debug entry-values
1129 show debug entry-values
1130 Control display of debugging info for determining frame argument values at
1131 function entry and virtual tail call frames.
1133 set basenames-may-differ
1134 show basenames-may-differ
1135 Set whether a source file may have multiple base names.
1136 (A "base name" is the name of a file with the directory part removed.
1137 Example: The base name of "/home/user/hello.c" is "hello.c".)
1138 If set, GDB will canonicalize file names (e.g., expand symlinks)
1139 before comparing them. Canonicalization is an expensive operation,
1140 but it allows the same file be known by more than one base name.
1141 If not set (the default), all source files are assumed to have just
1142 one base name, and gdb will do file name comparisons more efficiently.
1148 Set a user name and notes for the current and any future trace runs.
1149 This is useful for long-running and/or disconnected traces, to
1150 inform others (or yourself) as to who is running the trace, supply
1151 contact information, or otherwise explain what is going on.
1153 set trace-stop-notes
1154 show trace-stop-notes
1155 Set a note attached to the trace run, that is displayed when the
1156 trace has been stopped by a tstop command. This is useful for
1157 instance as an explanation, if you are stopping a trace run that was
1158 started by someone else.
1160 * New remote packets
1164 Dynamically enable a tracepoint in a started trace experiment.
1168 Dynamically disable a tracepoint in a started trace experiment.
1172 Set the user and notes of the trace run.
1176 Query the current status of a tracepoint.
1180 Query the minimum length of instruction at which a fast tracepoint may
1183 * Dcache size (number of lines) and line-size are now runtime-configurable
1184 via "set dcache line" and "set dcache line-size" commands.
1188 Texas Instruments TMS320C6x tic6x-*-*
1192 Renesas RL78 rl78-*-elf
1194 *** Changes in GDB 7.3.1
1196 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1198 *** Changes in GDB 7.3
1200 * GDB has a new command: "thread find [REGEXP]".
1201 It finds the thread id whose name, target id, or thread extra info
1202 matches the given regular expression.
1204 * The "catch syscall" command now works on mips*-linux* targets.
1206 * The -data-disassemble MI command now supports modes 2 and 3 for
1207 dumping the instruction opcodes.
1209 * New command line options
1211 -data-directory DIR Specify DIR as the "data-directory".
1212 This is mostly for testing purposes.
1214 * The "maint set python auto-load on|off" command has been renamed to
1215 "set auto-load-scripts on|off".
1217 * GDB has a new command: "set directories".
1218 It is like the "dir" command except that it replaces the
1219 source path list instead of augmenting it.
1221 * GDB now understands thread names.
1223 On GNU/Linux, "info threads" will display the thread name as set by
1224 prctl or pthread_setname_np.
1226 There is also a new command, "thread name", which can be used to
1227 assign a name internally for GDB to display.
1230 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1231 has been integrated into GDB.
1235 ** The function gdb.Write now accepts an optional keyword 'stream'.
1236 This keyword, when provided, will direct the output to either
1237 stdout, stderr, or GDB's logging output.
1239 ** Parameters can now be be sub-classed in Python, and in particular
1240 you may implement the get_set_doc and get_show_doc functions.
1241 This improves how Parameter set/show documentation is processed
1242 and allows for more dynamic content.
1244 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1245 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1246 have an is_valid method.
1248 ** Breakpoints can now be sub-classed in Python, and in particular
1249 you may implement a 'stop' function that is executed each time
1250 the inferior reaches that breakpoint.
1252 ** New function gdb.lookup_global_symbol looks up a global symbol.
1254 ** GDB values in Python are now callable if the value represents a
1255 function. For example, if 'some_value' represents a function that
1256 takes two integer parameters and returns a value, you can call
1257 that function like so:
1259 result = some_value (10,20)
1261 ** Module gdb.types has been added.
1262 It contains a collection of utilities for working with gdb.Types objects:
1263 get_basic_type, has_field, make_enum_dict.
1265 ** Module gdb.printing has been added.
1266 It contains utilities for writing and registering pretty-printers.
1267 New classes: PrettyPrinter, SubPrettyPrinter,
1268 RegexpCollectionPrettyPrinter.
1269 New function: register_pretty_printer.
1271 ** New commands "info pretty-printers", "enable pretty-printer" and
1272 "disable pretty-printer" have been added.
1274 ** gdb.parameter("directories") is now available.
1276 ** New function gdb.newest_frame returns the newest frame in the
1279 ** The gdb.InferiorThread class has a new "name" attribute. This
1280 holds the thread's name.
1282 ** Python Support for Inferior events.
1283 Python scripts can add observers to be notified of events
1284 occurring in the process being debugged.
1285 The following events are currently supported:
1286 - gdb.events.cont Continue event.
1287 - gdb.events.exited Inferior exited event.
1288 - gdb.events.stop Signal received, and Breakpoint hit events.
1292 ** GDB now puts template parameters in scope when debugging in an
1293 instantiation. For example, if you have:
1295 template<int X> int func (void) { return X; }
1297 then if you step into func<5>, "print X" will show "5". This
1298 feature requires proper debuginfo support from the compiler; it
1299 was added to GCC 4.5.
1301 ** The motion commands "next", "finish", "until", and "advance" now
1302 work better when exceptions are thrown. In particular, GDB will
1303 no longer lose control of the inferior; instead, the GDB will
1304 stop the inferior at the point at which the exception is caught.
1305 This functionality requires a change in the exception handling
1306 code that was introduced in GCC 4.5.
1308 * GDB now follows GCC's rules on accessing volatile objects when
1309 reading or writing target state during expression evaluation.
1310 One notable difference to prior behavior is that "print x = 0"
1311 no longer generates a read of x; the value of the assignment is
1312 now always taken directly from the value being assigned.
1314 * GDB now has some support for using labels in the program's source in
1315 linespecs. For instance, you can use "advance label" to continue
1316 execution to a label.
1318 * GDB now has support for reading and writing a new .gdb_index
1319 section. This section holds a fast index of DWARF debugging
1320 information and can be used to greatly speed up GDB startup and
1321 operation. See the documentation for `save gdb-index' for details.
1323 * The "watch" command now accepts an optional "-location" argument.
1324 When used, this causes GDB to watch the memory referred to by the
1325 expression. Such a watchpoint is never deleted due to it going out
1328 * GDB now supports thread debugging of core dumps on GNU/Linux.
1330 GDB now activates thread debugging using the libthread_db library
1331 when debugging GNU/Linux core dumps, similarly to when debugging
1332 live processes. As a result, when debugging a core dump file, GDB
1333 is now able to display pthread_t ids of threads. For example, "info
1334 threads" shows the same output as when debugging the process when it
1335 was live. In earlier releases, you'd see something like this:
1338 * 1 LWP 6780 main () at main.c:10
1340 While now you see this:
1343 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1345 It is also now possible to inspect TLS variables when debugging core
1348 When debugging a core dump generated on a machine other than the one
1349 used to run GDB, you may need to point GDB at the correct
1350 libthread_db library with the "set libthread-db-search-path"
1351 command. See the user manual for more details on this command.
1353 * When natively debugging programs on PowerPC BookE processors running
1354 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1355 which stop execution of the inferior whenever it executes an instruction
1356 at any address within the specified range. See the "PowerPC Embedded"
1357 section in the user manual for more details.
1359 * New features in the GDB remote stub, GDBserver
1361 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1362 and i686 LynxOS (version 5.x).
1364 ** GDBserver is now supported on Blackfin Linux.
1366 * New native configurations
1368 ia64 HP-UX ia64-*-hpux*
1372 Analog Devices, Inc. Blackfin Processor bfin-*
1374 * Ada task switching is now supported on sparc-elf targets when
1375 debugging a program using the Ravenscar Profile. For more information,
1376 see the "Tasking Support when using the Ravenscar Profile" section
1377 in the GDB user manual.
1379 * Guile support was removed.
1381 * New features in the GNU simulator
1383 ** The --map-info flag lists all known core mappings.
1385 ** CFI flashes may be simulated via the "cfi" device.
1387 *** Changes in GDB 7.2
1389 * Shared library support for remote targets by default
1391 When GDB is configured for a generic, non-OS specific target, like
1392 for example, --target=arm-eabi or one of the many *-*-elf targets,
1393 GDB now queries remote stubs for loaded shared libraries using the
1394 `qXfer:libraries:read' packet. Previously, shared library support
1395 was always disabled for such configurations.
1399 ** Argument Dependent Lookup (ADL)
1401 In C++ ADL lookup directs function search to the namespaces of its
1402 arguments even if the namespace has not been imported.
1412 Here the compiler will search for `foo' in the namespace of 'b'
1413 and find A::foo. GDB now supports this. This construct is commonly
1414 used in the Standard Template Library for operators.
1416 ** Improved User Defined Operator Support
1418 In addition to member operators, GDB now supports lookup of operators
1419 defined in a namespace and imported with a `using' directive, operators
1420 defined in the global scope, operators imported implicitly from an
1421 anonymous namespace, and the ADL operators mentioned in the previous
1423 GDB now also supports proper overload resolution for all the previously
1424 mentioned flavors of operators.
1426 ** static const class members
1428 Printing of static const class members that are initialized in the
1429 class definition has been fixed.
1431 * Windows Thread Information Block access.
1433 On Windows targets, GDB now supports displaying the Windows Thread
1434 Information Block (TIB) structure. This structure is visible either
1435 by using the new command `info w32 thread-information-block' or, by
1436 dereferencing the new convenience variable named `$_tlb', a
1437 thread-specific pointer to the TIB. This feature is also supported
1438 when remote debugging using GDBserver.
1440 * Static tracepoints
1442 Static tracepoints are calls in the user program into a tracing
1443 library. One such library is a port of the LTTng kernel tracer to
1444 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1445 When debugging with GDBserver, GDB now supports combining the GDB
1446 tracepoint machinery with such libraries. For example: the user can
1447 use GDB to probe a static tracepoint marker (a call from the user
1448 program into the tracing library) with the new "strace" command (see
1449 "New commands" below). This creates a "static tracepoint" in the
1450 breakpoint list, that can be manipulated with the same feature set
1451 as fast and regular tracepoints. E.g., collect registers, local and
1452 global variables, collect trace state variables, and define
1453 tracepoint conditions. In addition, the user can collect extra
1454 static tracepoint marker specific data, by collecting the new
1455 $_sdata internal variable. When analyzing the trace buffer, you can
1456 inspect $_sdata like any other variable available to GDB. For more
1457 information, see the "Tracepoints" chapter in GDB user manual. New
1458 remote packets have been defined to support static tracepoints, see
1459 the "New remote packets" section below.
1461 * Better reconstruction of tracepoints after disconnected tracing
1463 GDB will attempt to download the original source form of tracepoint
1464 definitions when starting a trace run, and then will upload these
1465 upon reconnection to the target, resulting in a more accurate
1466 reconstruction of the tracepoints that are in use on the target.
1470 You can now exercise direct control over the ways that GDB can
1471 affect your program. For instance, you can disallow the setting of
1472 breakpoints, so that the program can run continuously (assuming
1473 non-stop mode). In addition, the "observer" variable is available
1474 to switch all of the different controls; in observer mode, GDB
1475 cannot affect the target's behavior at all, which is useful for
1476 tasks like diagnosing live systems in the field.
1478 * The new convenience variable $_thread holds the number of the
1481 * New remote packets
1485 Return the address of the Windows Thread Information Block of a given thread.
1489 In response to several of the tracepoint packets, the target may now
1490 also respond with a number of intermediate `qRelocInsn' request
1491 packets before the final result packet, to have GDB handle
1492 relocating an instruction to execute at a different address. This
1493 is particularly useful for stubs that support fast tracepoints. GDB
1494 reports support for this feature in the qSupported packet.
1498 List static tracepoint markers in the target program.
1502 List static tracepoint markers at a given address in the target
1505 qXfer:statictrace:read
1507 Read the static trace data collected (by a `collect $_sdata'
1508 tracepoint action). The remote stub reports support for this packet
1509 to gdb's qSupported query.
1513 Send the current settings of GDB's permission flags.
1517 Send part of the source (textual) form of a tracepoint definition,
1518 which includes location, conditional, and action list.
1520 * The source command now accepts a -s option to force searching for the
1521 script in the source search path even if the script name specifies
1524 * New features in the GDB remote stub, GDBserver
1526 - GDBserver now support tracepoints (including fast tracepoints, and
1527 static tracepoints). The feature is currently supported by the
1528 i386-linux and amd64-linux builds. See the "Tracepoints support
1529 in gdbserver" section in the manual for more information.
1531 GDBserver JIT compiles the tracepoint's conditional agent
1532 expression bytecode into native code whenever possible for low
1533 overhead dynamic tracepoints conditionals. For such tracepoints,
1534 an expression that examines program state is evaluated when the
1535 tracepoint is reached, in order to determine whether to capture
1536 trace data. If the condition is simple and false, processing the
1537 tracepoint finishes very quickly and no data is gathered.
1539 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1540 for static tracepoints support.
1542 - GDBserver now supports x86_64 Windows 64-bit debugging.
1544 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1545 it understands register description.
1547 * The --batch flag now disables pagination and queries.
1549 * X86 general purpose registers
1551 GDB now supports reading/writing byte, word and double-word x86
1552 general purpose registers directly. This means you can use, say,
1553 $ah or $ax to refer, respectively, to the byte register AH and
1554 16-bit word register AX that are actually portions of the 32-bit
1555 register EAX or 64-bit register RAX.
1557 * The `commands' command now accepts a range of breakpoints to modify.
1558 A plain `commands' following a command that creates multiple
1559 breakpoints affects all the breakpoints set by that command. This
1560 applies to breakpoints set by `rbreak', and also applies when a
1561 single `break' command creates multiple breakpoints (e.g.,
1562 breakpoints on overloaded c++ functions).
1564 * The `rbreak' command now accepts a filename specification as part of
1565 its argument, limiting the functions selected by the regex to those
1566 in the specified file.
1568 * Support for remote debugging Windows and SymbianOS shared libraries
1569 from Unix hosts has been improved. Non Windows GDB builds now can
1570 understand target reported file names that follow MS-DOS based file
1571 system semantics, such as file names that include drive letters and
1572 use the backslash character as directory separator. This makes it
1573 possible to transparently use the "set sysroot" and "set
1574 solib-search-path" on Unix hosts to point as host copies of the
1575 target's shared libraries. See the new command "set
1576 target-file-system-kind" described below, and the "Commands to
1577 specify files" section in the user manual for more information.
1581 eval template, expressions...
1582 Convert the values of one or more expressions under the control
1583 of the string template to a command line, and call it.
1585 set target-file-system-kind unix|dos-based|auto
1586 show target-file-system-kind
1587 Set or show the assumed file system kind for target reported file
1590 save breakpoints <filename>
1591 Save all current breakpoint definitions to a file suitable for use
1592 in a later debugging session. To read the saved breakpoint
1593 definitions, use the `source' command.
1595 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1598 info static-tracepoint-markers
1599 Display information about static tracepoint markers in the target.
1601 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1602 Define a static tracepoint by probing a marker at the given
1603 function, line, address, or marker ID.
1607 Enable and disable observer mode.
1609 set may-write-registers on|off
1610 set may-write-memory on|off
1611 set may-insert-breakpoints on|off
1612 set may-insert-tracepoints on|off
1613 set may-insert-fast-tracepoints on|off
1614 set may-interrupt on|off
1615 Set individual permissions for GDB effects on the target. Note that
1616 some of these settings can have undesirable or surprising
1617 consequences, particularly when changed in the middle of a session.
1618 For instance, disabling the writing of memory can prevent
1619 breakpoints from being inserted, cause single-stepping to fail, or
1620 even crash your program, if you disable after breakpoints have been
1621 inserted. However, GDB should not crash.
1623 set record memory-query on|off
1624 show record memory-query
1625 Control whether to stop the inferior if memory changes caused
1626 by an instruction cannot be recorded.
1631 The disassemble command now supports "start,+length" form of two arguments.
1635 ** GDB now provides a new directory location, called the python directory,
1636 where Python scripts written for GDB can be installed. The location
1637 of that directory is <data-directory>/python, where <data-directory>
1638 is the GDB data directory. For more details, see section `Scripting
1639 GDB using Python' in the manual.
1641 ** The GDB Python API now has access to breakpoints, symbols, symbol
1642 tables, program spaces, inferiors, threads and frame's code blocks.
1643 Additionally, GDB Parameters can now be created from the API, and
1644 manipulated via set/show in the CLI.
1646 ** New functions gdb.target_charset, gdb.target_wide_charset,
1647 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1649 ** New exception gdb.GdbError.
1651 ** Pretty-printers are now also looked up in the current program space.
1653 ** Pretty-printers can now be individually enabled and disabled.
1655 ** GDB now looks for names of Python scripts to auto-load in a
1656 special section named `.debug_gdb_scripts', in addition to looking
1657 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1659 * Tracepoint actions were unified with breakpoint commands. In particular,
1660 there are no longer differences in "info break" output for breakpoints and
1661 tracepoints and the "commands" command can be used for both tracepoints and
1662 regular breakpoints.
1666 ARM Symbian arm*-*-symbianelf*
1668 * D language support.
1669 GDB now supports debugging programs written in the D programming
1672 * GDB now supports the extended ptrace interface for PowerPC which is
1673 available since Linux kernel version 2.6.34. This automatically enables
1674 any hardware breakpoints and additional hardware watchpoints available in
1675 the processor. The old ptrace interface exposes just one hardware
1676 watchpoint and no hardware breakpoints.
1678 * GDB is now able to use the Data Value Compare (DVC) register available on
1679 embedded PowerPC processors to implement in hardware simple watchpoint
1680 conditions of the form:
1682 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1684 This works in native GDB running on Linux kernels with the extended ptrace
1685 interface mentioned above.
1687 *** Changes in GDB 7.1
1691 ** Namespace Support
1693 GDB now supports importing of namespaces in C++. This enables the
1694 user to inspect variables from imported namespaces. Support for
1695 namepace aliasing has also been added. So, if a namespace is
1696 aliased in the current scope (e.g. namepace C=A; ) the user can
1697 print variables using the alias (e.g. (gdb) print C::x).
1701 All known bugs relating to the printing of virtual base class were
1702 fixed. It is now possible to call overloaded static methods using a
1707 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1708 and reinterpret_cast<> are now handled by the C++ expression parser.
1712 Xilinx MicroBlaze microblaze-*-*
1717 Xilinx MicroBlaze microblaze
1720 * Multi-program debugging.
1722 GDB now has support for multi-program (a.k.a. multi-executable or
1723 multi-exec) debugging. This allows for debugging multiple inferiors
1724 simultaneously each running a different program under the same GDB
1725 session. See "Debugging Multiple Inferiors and Programs" in the
1726 manual for more information. This implied some user visible changes
1727 in the multi-inferior support. For example, "info inferiors" now
1728 lists inferiors that are not running yet or that have exited
1729 already. See also "New commands" and "New options" below.
1731 * New tracing features
1733 GDB's tracepoint facility now includes several new features:
1735 ** Trace state variables
1737 GDB tracepoints now include support for trace state variables, which
1738 are variables managed by the target agent during a tracing
1739 experiment. They are useful for tracepoints that trigger each
1740 other, so for instance one tracepoint can count hits in a variable,
1741 and then a second tracepoint has a condition that is true when the
1742 count reaches a particular value. Trace state variables share the
1743 $-syntax of GDB convenience variables, and can appear in both
1744 tracepoint actions and condition expressions. Use the "tvariable"
1745 command to create, and "info tvariables" to view; see "Trace State
1746 Variables" in the manual for more detail.
1750 GDB now includes an option for defining fast tracepoints, which
1751 targets may implement more efficiently, such as by installing a jump
1752 into the target agent rather than a trap instruction. The resulting
1753 speedup can be by two orders of magnitude or more, although the
1754 tradeoff is that some program locations on some target architectures
1755 might not allow fast tracepoint installation, for instance if the
1756 instruction to be replaced is shorter than the jump. To request a
1757 fast tracepoint, use the "ftrace" command, with syntax identical to
1758 the regular trace command.
1760 ** Disconnected tracing
1762 It is now possible to detach GDB from the target while it is running
1763 a trace experiment, then reconnect later to see how the experiment
1764 is going. In addition, a new variable disconnected-tracing lets you
1765 tell the target agent whether to continue running a trace if the
1766 connection is lost unexpectedly.
1770 GDB now has the ability to save the trace buffer into a file, and
1771 then use that file as a target, similarly to you can do with
1772 corefiles. You can select trace frames, print data that was
1773 collected in them, and use tstatus to display the state of the
1774 tracing run at the moment that it was saved. To create a trace
1775 file, use "tsave <filename>", and to use it, do "target tfile
1778 ** Circular trace buffer
1780 You can ask the target agent to handle the trace buffer as a
1781 circular buffer, discarding the oldest trace frames to make room for
1782 newer ones, by setting circular-trace-buffer to on. This feature may
1783 not be available for all target agents.
1788 The disassemble command, when invoked with two arguments, now requires
1789 the arguments to be comma-separated.
1792 The info variables command now displays variable definitions. Files
1793 which only declare a variable are not shown.
1796 The source command is now capable of sourcing Python scripts.
1797 This feature is dependent on the debugger being build with Python
1800 Related to this enhancement is also the introduction of a new command
1801 "set script-extension" (see below).
1803 * New commands (for set/show, see "New options" below)
1805 record save [<FILENAME>]
1806 Save a file (in core file format) containing the process record
1807 execution log for replay debugging at a later time.
1809 record restore <FILENAME>
1810 Restore the process record execution log that was saved at an
1811 earlier time, for replay debugging.
1813 add-inferior [-copies <N>] [-exec <FILENAME>]
1816 clone-inferior [-copies <N>] [ID]
1817 Make a new inferior ready to execute the same program another
1818 inferior has loaded.
1823 maint info program-spaces
1824 List the program spaces loaded into GDB.
1826 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1827 show remote interrupt-sequence
1828 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1829 as the sequence to the remote target in order to interrupt the execution.
1830 Ctrl-C is a default. Some system prefers BREAK which is high level of
1831 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1832 Magic SysRq g. It is BREAK signal and character 'g'.
1834 set remote interrupt-on-connect [on | off]
1835 show remote interrupt-on-connect
1836 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1837 remote target when gdb connects to it. This is needed when you debug
1840 set remotebreak [on | off]
1842 Deprecated. Use "set/show remote interrupt-sequence" instead.
1844 tvariable $NAME [ = EXP ]
1845 Create or modify a trace state variable.
1848 List trace state variables and their values.
1850 delete tvariable $NAME ...
1851 Delete one or more trace state variables.
1854 Evaluate the given expressions without collecting anything into the
1855 trace buffer. (Valid in tracepoint actions only.)
1857 ftrace FN / FILE:LINE / *ADDR
1858 Define a fast tracepoint at the given function, line, or address.
1860 * New expression syntax
1862 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1863 GDB now parses 0b101010 identically with 42.
1867 set follow-exec-mode new|same
1868 show follow-exec-mode
1869 Control whether GDB reuses the same inferior across an exec call or
1870 creates a new one. This is useful to be able to restart the old
1871 executable after the inferior having done an exec call.
1873 set default-collect EXPR, ...
1874 show default-collect
1875 Define a list of expressions to be collected at each tracepoint.
1876 This is a useful way to ensure essential items are not overlooked,
1877 such as registers or a critical global variable.
1879 set disconnected-tracing
1880 show disconnected-tracing
1881 If set to 1, the target is instructed to continue tracing if it
1882 loses its connection to GDB. If 0, the target is to stop tracing
1885 set circular-trace-buffer
1886 show circular-trace-buffer
1887 If set to on, the target is instructed to use a circular trace buffer
1888 and discard the oldest trace frames instead of stopping the trace due
1889 to a full trace buffer. If set to off, the trace stops when the buffer
1890 fills up. Some targets may not support this.
1892 set script-extension off|soft|strict
1893 show script-extension
1894 If set to "off", the debugger does not perform any script language
1895 recognition, and all sourced files are assumed to be GDB scripts.
1896 If set to "soft" (the default), files are sourced according to
1897 filename extension, falling back to GDB scripts if the first
1899 If set to "strict", files are sourced according to filename extension.
1901 set ada trust-PAD-over-XVS on|off
1902 show ada trust-PAD-over-XVS
1903 If off, activate a workaround against a bug in the debugging information
1904 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1905 the GCC sources for more information about the GNAT encoding and
1906 PAD types in particular). It is always safe to set this option to
1907 off, but this introduces a slight performance penalty. The default
1910 * Python API Improvements
1912 ** GDB provides the new class gdb.LazyString. This is useful in
1913 some pretty-printing cases. The new method gdb.Value.lazy_string
1914 provides a simple way to create objects of this type.
1916 ** The fields returned by gdb.Type.fields now have an
1917 `is_base_class' attribute.
1919 ** The new method gdb.Type.range returns the range of an array type.
1921 ** The new method gdb.parse_and_eval can be used to parse and
1922 evaluate an expression.
1924 * New remote packets
1927 Define a trace state variable.
1930 Get the current value of a trace state variable.
1933 Set desired tracing behavior upon disconnection.
1936 Set the trace buffer to be linear or circular.
1939 Get data about the tracepoints currently in use.
1943 Process record now works correctly with hardware watchpoints.
1945 Multiple bug fixes have been made to the mips-irix port, making it
1946 much more reliable. In particular:
1947 - Debugging threaded applications is now possible again. Previously,
1948 GDB would hang while starting the program, or while waiting for
1949 the program to stop at a breakpoint.
1950 - Attaching to a running process no longer hangs.
1951 - An error occurring while loading a core file has been fixed.
1952 - Changing the value of the PC register now works again. This fixes
1953 problems observed when using the "jump" command, or when calling
1954 a function from GDB, or even when assigning a new value to $pc.
1955 - With the "finish" and "return" commands, the return value for functions
1956 returning a small array is now correctly printed.
1957 - It is now possible to break on shared library code which gets executed
1958 during a shared library init phase (code executed while executing
1959 their .init section). Previously, the breakpoint would have no effect.
1960 - GDB is now able to backtrace through the signal handler for
1961 non-threaded programs.
1963 PIE (Position Independent Executable) programs debugging is now supported.
1964 This includes debugging execution of PIC (Position Independent Code) shared
1965 libraries although for that, it should be possible to run such libraries as an
1968 *** Changes in GDB 7.0
1970 * GDB now has an interface for JIT compilation. Applications that
1971 dynamically generate code can create symbol files in memory and register
1972 them with GDB. For users, the feature should work transparently, and
1973 for JIT developers, the interface is documented in the GDB manual in the
1974 "JIT Compilation Interface" chapter.
1976 * Tracepoints may now be conditional. The syntax is as for
1977 breakpoints; either an "if" clause appended to the "trace" command,
1978 or the "condition" command is available. GDB sends the condition to
1979 the target for evaluation using the same bytecode format as is used
1980 for tracepoint actions.
1982 * The disassemble command now supports: an optional /r modifier, print the
1983 raw instructions in hex as well as in symbolic form, and an optional /m
1984 modifier to print mixed source+assembly.
1986 * Process record and replay
1988 In a architecture environment that supports ``process record and
1989 replay'', ``process record and replay'' target can record a log of
1990 the process execution, and replay it with both forward and reverse
1993 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1994 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1995 set execution-direction {forward|reverse}, for targets that support
1998 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1999 feature is available with a native GDB running on kernel version
2002 * GDB now has support for multi-byte and wide character sets on the
2003 target. Strings whose character type is wchar_t, char16_t, or
2004 char32_t are now correctly printed. GDB supports wide- and unicode-
2005 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2006 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2007 `printf'. This feature requires iconv to work properly; if your
2008 system does not have a working iconv, GDB can use GNU libiconv. See
2009 the installation instructions for more information.
2011 * GDB now supports automatic retrieval of shared library files from
2012 remote targets. To use this feature, specify a system root that begins
2013 with the `remote:' prefix, either via the `set sysroot' command or via
2014 the `--with-sysroot' configure-time option.
2016 * "info sharedlibrary" now takes an optional regex of libraries to show,
2017 and it now reports if a shared library has no debugging information.
2019 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2020 now complete on file names.
2022 * When completing in expressions, gdb will attempt to limit
2023 completions to allowable structure or union fields, where appropriate.
2024 For instance, consider:
2026 # struct example { int f1; double f2; };
2027 # struct example variable;
2030 If the user types TAB at the end of this command line, the available
2031 completions will be "f1" and "f2".
2033 * Inlined functions are now supported. They show up in backtraces, and
2034 the "step", "next", and "finish" commands handle them automatically.
2036 * GDB now supports the token-splicing (##) and stringification (#)
2037 operators when expanding macros. It also supports variable-arity
2040 * GDB now supports inspecting extra signal information, exported by
2041 the new $_siginfo convenience variable. The feature is currently
2042 implemented on linux ARM, i386 and amd64.
2044 * GDB can now display the VFP floating point registers and NEON vector
2045 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2046 can provide these registers (requires Linux 2.6.30 or later). Remote
2047 and simulator targets may also provide them.
2049 * New remote packets
2052 Search memory for a sequence of bytes.
2055 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2056 operation over reliable transport links. Use of this packet is
2057 controlled by the `set remote noack-packet' command.
2060 Kill the process with the specified process ID. Use this in preference
2061 to `k' when multiprocess protocol extensions are supported.
2064 Obtains additional operating system information
2068 Read or write additional signal information.
2070 * Removed remote protocol undocumented extension
2072 An undocumented extension to the remote protocol's `S' stop reply
2073 packet that permited the stub to pass a process id was removed.
2074 Remote servers should use the `T' stop reply packet instead.
2076 * GDB now supports multiple function calling conventions according to the
2077 DWARF-2 DW_AT_calling_convention function attribute.
2079 * The SH target utilizes the aforementioned change to distinguish between gcc
2080 and Renesas calling convention. It also adds the new CLI commands
2081 `set/show sh calling-convention'.
2083 * GDB can now read compressed debug sections, as produced by GNU gold
2084 with the --compress-debug-sections=zlib flag.
2086 * 64-bit core files are now supported on AIX.
2088 * Thread switching is now supported on Tru64.
2090 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2091 which will be allocated using malloc later in program execution.
2093 * The qXfer:libraries:read remote procotol packet now allows passing a
2094 list of section offsets.
2096 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2097 conditions handling signals delivered during attach or thread creation
2098 have also been fixed.
2100 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2101 From the user's standpoint, all unqualified instances of True and False
2102 are treated as the standard definitions, regardless of context.
2104 * GDB now parses C++ symbol and type names more flexibly. For
2107 template<typename T> class C { };
2110 GDB will now correctly handle all of:
2112 ptype C<char const *>
2113 ptype C<char const*>
2114 ptype C<const char *>
2115 ptype C<const char*>
2117 * New features in the GDB remote stub, gdbserver
2119 - The "--wrapper" command-line argument tells gdbserver to use a
2120 wrapper program to launch programs for debugging.
2122 - On PowerPC and S/390 targets, it is now possible to use a single
2123 gdbserver executable to debug both 32-bit and 64-bit programs.
2124 (This requires gdbserver itself to be built as a 64-bit executable.)
2126 - gdbserver uses the new noack protocol mode for TCP connections to
2127 reduce communications latency, if also supported and enabled in GDB.
2129 - Support for the sparc64-linux-gnu target is now included in
2132 - The amd64-linux build of gdbserver now supports debugging both
2133 32-bit and 64-bit programs.
2135 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2136 now support hardware watchpoints, and will use them automatically
2141 GDB now has support for scripting using Python. Whether this is
2142 available is determined at configure time.
2144 New GDB commands can now be written in Python.
2146 * Ada tasking support
2148 Ada tasks can now be inspected in GDB. The following commands have
2152 Print the list of Ada tasks.
2154 Print detailed information about task number N.
2156 Print the task number of the current task.
2158 Switch the context of debugging to task number N.
2160 * Support for user-defined prefixed commands. The "define" command can
2161 add new commands to existing prefixes, e.g. "target".
2163 * Multi-inferior, multi-process debugging.
2165 GDB now has generalized support for multi-inferior debugging. See
2166 "Debugging Multiple Inferiors" in the manual for more information.
2167 Although availability still depends on target support, the command
2168 set is more uniform now. The GNU/Linux specific multi-forks support
2169 has been migrated to this new framework. This implied some user
2170 visible changes; see "New commands" and also "Removed commands"
2173 * Target descriptions can now describe the target OS ABI. See the
2174 "Target Description Format" section in the user manual for more
2177 * Target descriptions can now describe "compatible" architectures
2178 to indicate that the target can execute applications for a different
2179 architecture in addition to those for the main target architecture.
2180 See the "Target Description Format" section in the user manual for
2183 * Multi-architecture debugging.
2185 GDB now includes general supports for debugging applications on
2186 hybrid systems that use more than one single processor architecture
2187 at the same time. Each such hybrid architecture still requires
2188 specific support to be added. The only hybrid architecture supported
2189 in this version of GDB is the Cell Broadband Engine.
2191 * GDB now supports integrated debugging of Cell/B.E. applications that
2192 use both the PPU and SPU architectures. To enable support for hybrid
2193 Cell/B.E. debugging, you need to configure GDB to support both the
2194 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2195 --enable-targets configure option.
2197 * Non-stop mode debugging.
2199 For some targets, GDB now supports an optional mode of operation in
2200 which you can examine stopped threads while other threads continue
2201 to execute freely. This is referred to as non-stop mode, with the
2202 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2203 section in the user manual for more information.
2205 To be able to support remote non-stop debugging, a remote stub needs
2206 to implement the non-stop mode remote protocol extensions, as
2207 described in the "Remote Non-Stop" section of the user manual. The
2208 GDB remote stub, gdbserver, has been adjusted to support these
2209 extensions on linux targets.
2211 * New commands (for set/show, see "New options" below)
2213 catch syscall [NAME(S) | NUMBER(S)]
2214 Catch system calls. Arguments, which should be names of system
2215 calls or their numbers, mean catch only those syscalls. Without
2216 arguments, every syscall will be caught. When the inferior issues
2217 any of the specified syscalls, GDB will stop and announce the system
2218 call, both when it is called and when its call returns. This
2219 feature is currently available with a native GDB running on the
2220 Linux Kernel, under the following architectures: x86, x86_64,
2221 PowerPC and PowerPC64.
2223 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2225 Search memory for a sequence of bytes.
2227 maint set python print-stack
2228 maint show python print-stack
2229 Show a stack trace when an error is encountered in a Python script.
2232 Invoke CODE by passing it to the Python interpreter.
2237 These allow macros to be defined, undefined, and listed
2241 Show operating system information about processes.
2244 List the inferiors currently under GDB's control.
2247 Switch focus to inferior number NUM.
2250 Detach from inferior number NUM.
2253 Kill inferior number NUM.
2257 set spu stop-on-load
2258 show spu stop-on-load
2259 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2261 set spu auto-flush-cache
2262 show spu auto-flush-cache
2263 Control whether to automatically flush the software-managed cache
2264 during Cell/B.E. debugging.
2266 set sh calling-convention
2267 show sh calling-convention
2268 Control the calling convention used when calling SH target functions.
2271 show debug timestamp
2272 Control display of timestamps with GDB debugging output.
2274 set disassemble-next-line
2275 show disassemble-next-line
2276 Control display of disassembled source lines or instructions when
2279 set remote noack-packet
2280 show remote noack-packet
2281 Set/show the use of remote protocol QStartNoAckMode packet. See above
2282 under "New remote packets."
2284 set remote query-attached-packet
2285 show remote query-attached-packet
2286 Control use of remote protocol `qAttached' (query-attached) packet.
2288 set remote read-siginfo-object
2289 show remote read-siginfo-object
2290 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2293 set remote write-siginfo-object
2294 show remote write-siginfo-object
2295 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2298 set remote reverse-continue
2299 show remote reverse-continue
2300 Control use of remote protocol 'bc' (reverse-continue) packet.
2302 set remote reverse-step
2303 show remote reverse-step
2304 Control use of remote protocol 'bs' (reverse-step) packet.
2306 set displaced-stepping
2307 show displaced-stepping
2308 Control displaced stepping mode. Displaced stepping is a way to
2309 single-step over breakpoints without removing them from the debuggee.
2310 Also known as "out-of-line single-stepping".
2313 show debug displaced
2314 Control display of debugging info for displaced stepping.
2316 maint set internal-error
2317 maint show internal-error
2318 Control what GDB does when an internal error is detected.
2320 maint set internal-warning
2321 maint show internal-warning
2322 Control what GDB does when an internal warning is detected.
2327 Use a wrapper program to launch programs for debugging.
2329 set multiple-symbols (all|ask|cancel)
2330 show multiple-symbols
2331 The value of this variable can be changed to adjust the debugger behavior
2332 when an expression or a breakpoint location contains an ambiguous symbol
2333 name (an overloaded function name, for instance).
2335 set breakpoint always-inserted
2336 show breakpoint always-inserted
2337 Keep breakpoints always inserted in the target, as opposed to inserting
2338 them when resuming the target, and removing them when the target stops.
2339 This option can improve debugger performance on slow remote targets.
2341 set arm fallback-mode (arm|thumb|auto)
2342 show arm fallback-mode
2343 set arm force-mode (arm|thumb|auto)
2345 These commands control how ARM GDB determines whether instructions
2346 are ARM or Thumb. The default for both settings is auto, which uses
2347 the current CPSR value for instructions without symbols; previous
2348 versions of GDB behaved as if "set arm fallback-mode arm".
2350 set disable-randomization
2351 show disable-randomization
2352 Standalone programs run with the virtual address space randomization enabled
2353 by default on some platforms. This option keeps the addresses stable across
2354 multiple debugging sessions.
2358 Control whether other threads are stopped or not when some thread hits
2363 Requests that asynchronous execution is enabled in the target, if available.
2364 In this case, it's possible to resume target in the background, and interact
2365 with GDB while the target is running. "show target-async" displays the
2366 current state of asynchronous execution of the target.
2368 set target-wide-charset
2369 show target-wide-charset
2370 The target-wide-charset is the name of the character set that GDB
2371 uses when printing characters whose type is wchar_t.
2373 set tcp auto-retry (on|off)
2375 set tcp connect-timeout
2376 show tcp connect-timeout
2377 These commands allow GDB to retry failed TCP connections to a remote stub
2378 with a specified timeout period; this is useful if the stub is launched
2379 in parallel with GDB but may not be ready to accept connections immediately.
2381 set libthread-db-search-path
2382 show libthread-db-search-path
2383 Control list of directories which GDB will search for appropriate
2386 set schedule-multiple (on|off)
2387 show schedule-multiple
2388 Allow GDB to resume all threads of all processes or only threads of
2389 the current process.
2393 Use more aggressive caching for accesses to the stack. This improves
2394 performance of remote debugging (particularly backtraces) without
2395 affecting correctness.
2397 set interactive-mode (on|off|auto)
2398 show interactive-mode
2399 Control whether GDB runs in interactive mode (on) or not (off).
2400 When in interactive mode, GDB waits for the user to answer all
2401 queries. Otherwise, GDB does not wait and assumes the default
2402 answer. When set to auto (the default), GDB determines which
2403 mode to use based on the stdin settings.
2408 For program forks, this is replaced by the new more generic `info
2409 inferiors' command. To list checkpoints, you can still use the
2410 `info checkpoints' command, which was an alias for the `info forks'
2414 Replaced by the new `inferior' command. To switch between
2415 checkpoints, you can still use the `restart' command, which was an
2416 alias for the `fork' command.
2419 This is removed, since some targets don't have a notion of
2420 processes. To switch between processes, you can still use the
2421 `inferior' command using GDB's own inferior number.
2424 For program forks, this is replaced by the new more generic `kill
2425 inferior' command. To delete a checkpoint, you can still use the
2426 `delete checkpoint' command, which was an alias for the `delete
2430 For program forks, this is replaced by the new more generic `detach
2431 inferior' command. To detach a checkpoint, you can still use the
2432 `detach checkpoint' command, which was an alias for the `detach
2435 * New native configurations
2437 x86/x86_64 Darwin i[34567]86-*-darwin*
2439 x86_64 MinGW x86_64-*-mingw*
2443 Lattice Mico32 lm32-*
2444 x86 DICOS i[34567]86-*-dicos*
2445 x86_64 DICOS x86_64-*-dicos*
2448 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2449 (mingw32ce) debugging.
2455 These commands were actually not implemented on any target.
2457 *** Changes in GDB 6.8
2459 * New native configurations
2461 NetBSD/hppa hppa*-*netbsd*
2462 Xtensa GNU/Linux xtensa*-*-linux*
2466 NetBSD/hppa hppa*-*-netbsd*
2467 Xtensa GNU/Lunux xtensa*-*-linux*
2469 * Change in command line behavior -- corefiles vs. process ids.
2471 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2472 attaching to process NUMBER fails, GDB no longer attempts to open a
2473 core file named NUMBER. Attaching to a program using the -c option
2474 is no longer supported. Instead, use the '-p' or '--pid' options.
2476 * GDB can now be built as a native debugger for debugging Windows x86
2477 (mingw32) Portable Executable (PE) programs.
2479 * Pending breakpoints no longer change their number when their address
2482 * GDB now supports breakpoints with multiple locations,
2483 including breakpoints on C++ constructors, inside C++ templates,
2484 and in inlined functions.
2486 * GDB's ability to debug optimized code has been improved. GDB more
2487 accurately identifies function bodies and lexical blocks that occupy
2488 more than one contiguous range of addresses.
2490 * Target descriptions can now describe registers for PowerPC.
2492 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2493 registers on PowerPC targets.
2495 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2496 targets even when the libthread_db library is not available.
2498 * The GDB remote stub, gdbserver, now supports the new file transfer
2499 commands (remote put, remote get, and remote delete).
2501 * The GDB remote stub, gdbserver, now supports run and attach in
2502 extended-remote mode.
2504 * hppa*64*-*-hpux11* target broken
2505 The debugger is unable to start a program and fails with the following
2506 error: "Error trying to get information about dynamic linker".
2507 The gdb-6.7 release is also affected.
2509 * GDB now supports the --enable-targets= configure option to allow
2510 building a single GDB executable that supports multiple remote
2511 target architectures.
2513 * GDB now supports debugging C and C++ programs which use the
2514 Decimal Floating Point extension. In addition, the PowerPC target
2515 now has a set of pseudo-registers to inspect decimal float values
2516 stored in two consecutive float registers.
2518 * The -break-insert MI command can optionally create pending
2521 * Improved support for debugging Ada
2522 Many improvements to the Ada language support have been made. These
2524 - Better support for Ada2005 interface types
2525 - Improved handling of arrays and slices in general
2526 - Better support for Taft-amendment types
2527 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2529 - Improved command completion in Ada
2532 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2537 set print frame-arguments (all|scalars|none)
2538 show print frame-arguments
2539 The value of this variable can be changed to control which argument
2540 values should be printed by the debugger when displaying a frame.
2545 Transfer files to and from a remote target, and delete remote files.
2552 Transfer files to and from a remote target, and delete remote files.
2554 * New remote packets
2561 Open, close, read, write, and delete files on the remote system.
2564 Attach to an existing process on the remote system, in extended-remote
2568 Run a new process on the remote system, in extended-remote mode.
2570 *** Changes in GDB 6.7
2572 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2573 bfd, libiberty and opcodes, as revealed by static analysis donated by
2574 Coverity, Inc. (http://scan.coverity.com).
2576 * When looking up multiply-defined global symbols, GDB will now prefer the
2577 symbol definition in the current shared library if it was built using the
2578 -Bsymbolic linker option.
2580 * When the Text User Interface (TUI) is not configured, GDB will now
2581 recognize the -tui command-line option and print a message that the TUI
2584 * The GDB remote stub, gdbserver, now has lower overhead for high
2585 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2587 * GDB for MIPS targets now autodetects whether a remote target provides
2588 32-bit or 64-bit register values.
2590 * Support for C++ member pointers has been improved.
2592 * GDB now understands XML target descriptions, which specify the
2593 target's overall architecture. GDB can read a description from
2594 a local file or over the remote serial protocol.
2596 * Vectors of single-byte data use a new integer type which is not
2597 automatically displayed as character or string data.
2599 * The /s format now works with the print command. It displays
2600 arrays of single-byte integers and pointers to single-byte integers
2603 * Target descriptions can now describe target-specific registers,
2604 for architectures which have implemented the support (currently
2605 only ARM, M68K, and MIPS).
2607 * GDB and the GDB remote stub, gdbserver, now support the XScale
2610 * The GDB remote stub, gdbserver, has been updated to support
2611 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2612 has been rewritten to use the standard GDB remote protocol.
2614 * GDB can now step into C++ functions which are called through thunks.
2616 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2618 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2619 layout. It also supports a TextSeg= and DataSeg= response when only
2620 segment base addresses (rather than offsets) are available.
2622 * The /i format now outputs any trailing branch delay slot instructions
2623 immediately following the last instruction within the count specified.
2625 * The GDB remote protocol "T" stop reply packet now supports a
2626 "library" response. Combined with the new "qXfer:libraries:read"
2627 packet, this response allows GDB to debug shared libraries on targets
2628 where the operating system manages the list of loaded libraries (e.g.
2629 Windows and SymbianOS).
2631 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2632 (DLLs) on Windows and Windows CE targets.
2634 * GDB now supports a faster verification that a .debug file matches its binary
2635 according to its build-id signature, if the signature is present.
2641 Enable or disable hardware flow control (RTS/CTS) on the serial port
2642 when debugging using remote targets.
2644 set mem inaccessible-by-default
2645 show mem inaccessible-by-default
2646 If the target supplies a memory map, for instance via the remote
2647 protocol's "qXfer:memory-map:read" packet, setting this variable
2648 prevents GDB from accessing memory outside the memory map. This
2649 is useful for targets with memory mapped registers or which react
2650 badly to accesses of unmapped address space.
2652 set breakpoint auto-hw
2653 show breakpoint auto-hw
2654 If the target supplies a memory map, for instance via the remote
2655 protocol's "qXfer:memory-map:read" packet, setting this variable
2656 lets GDB use hardware breakpoints automatically for memory regions
2657 where it can not use software breakpoints. This covers both the
2658 "break" command and internal breakpoints used for other commands
2659 including "next" and "finish".
2662 catch exception unhandled
2663 Stop the program execution when Ada exceptions are raised.
2666 Stop the program execution when an Ada assertion failed.
2670 Set an alternate system root for target files. This is a more
2671 general version of "set solib-absolute-prefix", which is now
2672 an alias to "set sysroot".
2675 Provide extended SPU facility status information. This set of
2676 commands is available only when debugging the Cell/B.E. SPU
2679 * New native configurations
2681 OpenBSD/sh sh*-*openbsd*
2684 unset tdesc filename
2686 Use the specified local file as an XML target description, and do
2687 not query the target for its built-in description.
2691 OpenBSD/sh sh*-*-openbsd*
2692 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2693 Toshiba Media Processor mep-elf
2695 * New remote packets
2698 Ignore the specified signals; pass them directly to the debugged program
2699 without stopping other threads or reporting them to GDB.
2701 qXfer:features:read:
2702 Read an XML target description from the target, which describes its
2707 Read or write contents of an spufs file on the target system. These
2708 packets are available only on the Cell/B.E. SPU architecture.
2710 qXfer:libraries:read:
2711 Report the loaded shared libraries. Combined with new "T" packet
2712 response, this packet allows GDB to debug shared libraries on
2713 targets where the operating system manages the list of loaded
2714 libraries (e.g. Windows and SymbianOS).
2718 Support for these obsolete configurations has been removed.
2726 i[34567]86-*-lynxos*
2727 i[34567]86-*-netware*
2728 i[34567]86-*-sco3.2v5*
2729 i[34567]86-*-sco3.2v4*
2731 i[34567]86-*-sysv4.2*
2734 i[34567]86-*-unixware2*
2735 i[34567]86-*-unixware*
2744 * Other removed features
2751 Various m68k-only ROM monitors.
2758 Various Renesas ROM monitors and debugging interfaces for SH and
2763 Support for a Macraigor serial interface to on-chip debugging.
2764 GDB does not directly support the newer parallel or USB
2769 A debug information format. The predecessor to DWARF 2 and
2770 DWARF 3, which are still supported.
2772 Support for the HP aCC compiler on HP-UX/PA-RISC
2774 SOM-encapsulated symbolic debugging information, automatic
2775 invocation of pxdb, and the aCC custom C++ ABI. This does not
2776 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2777 with aCC can still be debugged on an assembly level.
2779 MIPS ".pdr" sections
2781 A MIPS-specific format used to describe stack frame layout
2782 in debugging information.
2786 GDB could work with an older version of Guile to debug
2787 the interpreter and Scheme programs running in it.
2789 set mips stack-arg-size
2790 set mips saved-gpreg-size
2792 Use "set mips abi" to control parameter passing for MIPS.
2794 *** Changes in GDB 6.6
2799 Cell Broadband Engine SPU spu-elf
2801 * GDB can now be configured as a cross-debugger targeting native Windows
2802 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2803 running on a Windows system over TCP/IP to debug Windows programs.
2805 * The GDB remote stub, gdbserver, has been updated to support Windows and
2806 Cygwin debugging. Both single-threaded and multi-threaded programs are
2809 * The "set trust-readonly-sections" command works again. This command was
2810 broken in GDB 6.3, 6.4, and 6.5.
2812 * The "load" command now supports writing to flash memory, if the remote
2813 stub provides the required support.
2815 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2816 longer requires symbolic debug information (e.g. DWARF-2).
2821 unset substitute-path
2822 show substitute-path
2823 Manage a list of substitution rules that GDB uses to rewrite the name
2824 of the directories where the sources are located. This can be useful
2825 for instance when the sources were moved to a different location
2826 between compilation and debugging.
2830 Print each CLI command as it is executed. Each command is prefixed with
2831 a number of `+' symbols representing the nesting depth.
2832 The source command now has a `-v' option to enable the same feature.
2836 The ARM Demon monitor support (RDP protocol, "target rdp").
2838 Kernel Object Display, an embedded debugging feature which only worked with
2839 an obsolete version of Cisco IOS.
2841 The 'set download-write-size' and 'show download-write-size' commands.
2843 * New remote packets
2846 Tell a stub about GDB client features, and request remote target features.
2847 The first feature implemented is PacketSize, which allows the target to
2848 specify the size of packets it can handle - to minimize the number of
2849 packets required and improve performance when connected to a remote
2853 Fetch an OS auxilliary vector from the remote stub. This packet is a
2854 more efficient replacement for qPart:auxv:read.
2856 qXfer:memory-map:read:
2857 Fetch a memory map from the remote stub, including information about
2858 RAM, ROM, and flash memory devices.
2863 Erase and program a flash memory device.
2865 * Removed remote packets
2868 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2869 used it, and only gdbserver implemented it.
2871 *** Changes in GDB 6.5
2875 Renesas M32C/M16C m32c-elf
2877 Morpho Technologies ms1 ms1-elf
2881 init-if-undefined Initialize a convenience variable, but
2882 only if it doesn't already have a value.
2884 The following commands are presently only implemented for native GNU/Linux:
2886 checkpoint Save a snapshot of the program state.
2888 restart <n> Return the program state to a
2889 previously saved state.
2891 info checkpoints List currently saved checkpoints.
2893 delete-checkpoint <n> Delete a previously saved checkpoint.
2895 set|show detach-on-fork Tell gdb whether to detach from a newly
2896 forked process, or to keep debugging it.
2898 info forks List forks of the user program that
2899 are available to be debugged.
2901 fork <n> Switch to debugging one of several
2902 forks of the user program that are
2903 available to be debugged.
2905 delete-fork <n> Delete a fork from the list of forks
2906 that are available to be debugged (and
2907 kill the forked process).
2909 detach-fork <n> Delete a fork from the list of forks
2910 that are available to be debugged (and
2911 allow the process to continue).
2915 Morpho Technologies ms2 ms1-elf
2917 * Improved Windows host support
2919 GDB now builds as a cross debugger hosted on i686-mingw32, including
2920 native console support, and remote communications using either
2921 network sockets or serial ports.
2923 * Improved Modula-2 language support
2925 GDB can now print most types in the Modula-2 syntax. This includes:
2926 basic types, set types, record types, enumerated types, range types,
2927 pointer types and ARRAY types. Procedure var parameters are correctly
2928 printed and hexadecimal addresses and character constants are also
2929 written in the Modula-2 syntax. Best results can be obtained by using
2930 GNU Modula-2 together with the -gdwarf-2 command line option.
2934 The ARM rdi-share module.
2936 The Netware NLM debug server.
2938 *** Changes in GDB 6.4
2940 * New native configurations
2942 OpenBSD/arm arm*-*-openbsd*
2943 OpenBSD/mips64 mips64-*-openbsd*
2947 Morpho Technologies ms1 ms1-elf
2949 * New command line options
2951 --batch-silent As for --batch, but totally silent.
2952 --return-child-result The debugger will exist with the same value
2953 the child (debugged) program exited with.
2954 --eval-command COMMAND, -ex COMMAND
2955 Execute a single GDB CLI command. This may be
2956 specified multiple times and in conjunction
2957 with the --command (-x) option.
2959 * Deprecated commands removed
2961 The following commands, that were deprecated in 2000, have been
2965 set|show arm disassembly-flavor set|show arm disassembler
2966 othernames set arm disassembler
2967 set|show remotedebug set|show debug remote
2968 set|show archdebug set|show debug arch
2969 set|show eventdebug set|show debug event
2972 * New BSD user-level threads support
2974 It is now possible to debug programs using the user-level threads
2975 library on OpenBSD and FreeBSD. Currently supported (target)
2978 FreeBSD/amd64 x86_64-*-freebsd*
2979 FreeBSD/i386 i386-*-freebsd*
2980 OpenBSD/i386 i386-*-openbsd*
2982 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2983 are not yet supported.
2985 * New support for Matsushita MN10300 w/sim added
2986 (Work in progress). mn10300-elf.
2988 * REMOVED configurations and files
2990 VxWorks and the XDR protocol *-*-vxworks
2991 Motorola MCORE mcore-*-*
2992 National Semiconductor NS32000 ns32k-*-*
2994 * New "set print array-indexes" command
2996 After turning this setting "on", GDB prints the index of each element
2997 when displaying arrays. The default is "off" to preserve the previous
3000 * VAX floating point support
3002 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3004 * User-defined command support
3006 In addition to using $arg0..$arg9 for argument passing, it is now possible
3007 to use $argc to determine now many arguments have been passed. See the
3008 section on user-defined commands in the user manual for more information.
3010 *** Changes in GDB 6.3:
3012 * New command line option
3014 GDB now accepts -l followed by a number to set the timeout for remote
3017 * GDB works with GCC -feliminate-dwarf2-dups
3019 GDB now supports a more compact representation of DWARF-2 debug
3020 information using DW_FORM_ref_addr references. These are produced
3021 by GCC with the option -feliminate-dwarf2-dups and also by some
3022 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3023 to use -feliminate-dwarf2-dups.
3025 * Internationalization
3027 When supported by the host system, GDB will be built with
3028 internationalization (libintl). The task of marking up the sources is
3029 continued, we're looking forward to our first translation.
3033 Initial support for debugging programs compiled with the GNAT
3034 implementation of the Ada programming language has been integrated
3035 into GDB. In this release, support is limited to expression evaluation.
3037 * New native configurations
3039 GNU/Linux/m32r m32r-*-linux-gnu
3043 GDB's remote protocol now includes support for the 'p' packet. This
3044 packet is used to fetch individual registers from a remote inferior.
3046 * END-OF-LIFE registers[] compatibility module
3048 GDB's internal register infrastructure has been completely rewritten.
3049 The new infrastructure making possible the implementation of key new
3050 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3053 GDB 6.3 will be the last release to include the the registers[]
3054 compatibility module that allowed out-of-date configurations to
3055 continue to work. This change directly impacts the following
3065 powerpc bdm protocol
3067 Unless there is activity to revive these configurations, they will be
3068 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3070 * OBSOLETE configurations and files
3072 Configurations that have been declared obsolete in this release have
3073 been commented out. Unless there is activity to revive these
3074 configurations, the next release of GDB will have their sources
3075 permanently REMOVED.
3084 *** Changes in GDB 6.2.1:
3086 * MIPS `break main; run' gave an heuristic-fence-post warning
3088 When attempting to run even a simple program, a warning about
3089 heuristic-fence-post being hit would be reported. This problem has
3092 * MIPS IRIX 'long double' crashed GDB
3094 When examining a long double variable, GDB would get a segmentation
3095 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3096 IRIX long double values).
3100 A bug in the VAX stack code was causing problems with the "next"
3101 command. This problem has been fixed.
3103 *** Changes in GDB 6.2:
3105 * Fix for ``many threads''
3107 On GNU/Linux systems that use the NPTL threads library, a program
3108 rapidly creating and deleting threads would confuse GDB leading to the
3111 ptrace: No such process.
3112 thread_db_get_info: cannot get thread info: generic error
3114 This problem has been fixed.
3116 * "-async" and "-noasync" options removed.
3118 Support for the broken "-noasync" option has been removed (it caused
3121 * New ``start'' command.
3123 This command runs the program until the begining of the main procedure.
3125 * New BSD Kernel Data Access Library (libkvm) interface
3127 Using ``target kvm'' it is now possible to debug kernel core dumps and
3128 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3129 platforms. Currently supported (native-only) configurations are:
3131 FreeBSD/amd64 x86_64-*-freebsd*
3132 FreeBSD/i386 i?86-*-freebsd*
3133 NetBSD/i386 i?86-*-netbsd*
3134 NetBSD/m68k m68*-*-netbsd*
3135 NetBSD/sparc sparc-*-netbsd*
3136 OpenBSD/amd64 x86_64-*-openbsd*
3137 OpenBSD/i386 i?86-*-openbsd*
3138 OpenBSD/m68k m68*-openbsd*
3139 OpenBSD/sparc sparc-*-openbsd*
3141 * Signal trampoline code overhauled
3143 Many generic problems with GDB's signal handling code have been fixed.
3144 These include: backtraces through non-contiguous stacks; recognition
3145 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3146 call; backtrace through a signal trampoline; step into and out of
3147 signal handlers; and single-stepping in the signal trampoline.
3149 Please note that kernel bugs are a limiting factor here. These
3150 features have been shown to work on an s390 GNU/Linux system that
3151 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3153 * Cygwin support for DWARF 2 added.
3155 * New native configurations
3157 GNU/Linux/hppa hppa*-*-linux*
3158 OpenBSD/hppa hppa*-*-openbsd*
3159 OpenBSD/m68k m68*-*-openbsd*
3160 OpenBSD/m88k m88*-*-openbsd*
3161 OpenBSD/powerpc powerpc-*-openbsd*
3162 NetBSD/vax vax-*-netbsd*
3163 OpenBSD/vax vax-*-openbsd*
3165 * END-OF-LIFE frame compatibility module
3167 GDB's internal frame infrastructure has been completely rewritten.
3168 The new infrastructure making it possible to support key new features
3169 including DWARF 2 Call Frame Information. To aid in the task of
3170 migrating old configurations to this new infrastructure, a
3171 compatibility module, that allowed old configurations to continue to
3172 work, was also included.
3174 GDB 6.2 will be the last release to include this frame compatibility
3175 module. This change directly impacts the following configurations:
3185 Unless there is activity to revive these configurations, they will be
3186 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3188 * REMOVED configurations and files
3190 Sun 3, running SunOS 3 m68*-*-sunos3*
3191 Sun 3, running SunOS 4 m68*-*-sunos4*
3192 Sun 2, running SunOS 3 m68000-*-sunos3*
3193 Sun 2, running SunOS 4 m68000-*-sunos4*
3194 Motorola 680x0 running LynxOS m68*-*-lynxos*
3195 AT&T 3b1/Unix pc m68*-att-*
3196 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3197 decstation mips-dec-* mips-little-*
3198 riscos mips-*-riscos* mips-*-sysv*
3199 sonymips mips-sony-*
3200 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3202 *** Changes in GDB 6.1.1:
3204 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3206 The TUI (Text-mode User Interface) is now built as part of a default
3207 GDB configuration. It is enabled by either selecting the TUI with the
3208 command line option "-i=tui" or by running the separate "gdbtui"
3209 program. For more information on the TUI, see the manual "Debugging
3212 * Pending breakpoint support (also included in GDB 6.1)
3214 Support has been added to allow you to specify breakpoints in shared
3215 libraries that have not yet been loaded. If a breakpoint location
3216 cannot be found, and the "breakpoint pending" option is set to auto,
3217 GDB queries you if you wish to make the breakpoint pending on a future
3218 shared-library load. If and when GDB resolves the breakpoint symbol,
3219 the pending breakpoint is removed as one or more regular breakpoints
3222 Pending breakpoints are very useful for GCJ Java debugging.
3224 * Fixed ISO-C build problems
3226 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3227 non ISO-C code that stopped them being built using a more strict ISO-C
3228 compiler (e.g., IBM's C compiler).
3230 * Fixed build problem on IRIX 5
3232 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3233 wasn't able to compile compile on an IRIX 5 system.
3235 * Added execute permission to gdb/gdbserver/configure
3237 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3238 permission. This bug would cause configure to fail on a number of
3239 systems (Solaris, IRIX). Ref: server/519.
3241 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3243 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3244 has been updated to use constant array sizes.
3246 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3248 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3249 its generated DWARF Call Frame Info. This encoding was causing GDB to
3250 panic, that panic has been fixed. Ref: gdb/1628.
3252 * Fixed a problem when examining parameters in shared library code.
3254 When examining parameters in optimized shared library code generated
3255 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3256 not available''. GDB now correctly displays the variable's value.
3258 *** Changes in GDB 6.1:
3260 * Removed --with-mmalloc
3262 Support for the mmalloc memory manager has been removed, as it
3263 conflicted with the internal gdb byte cache.
3265 * Changes in AMD64 configurations
3267 The AMD64 target now includes the %cs and %ss registers. As a result
3268 the AMD64 remote protocol has changed; this affects the floating-point
3269 and SSE registers. If you rely on those registers for your debugging,
3270 you should upgrade gdbserver on the remote side.
3272 * Revised SPARC target
3274 The SPARC target has been completely revised, incorporating the
3275 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3276 support for LynxOS and SunOS 4 has been dropped. Calling functions
3277 from within GDB on operating systems with a non-executable stack
3278 (Solaris, OpenBSD) now works.
3282 GDB has a new C++ demangler which does a better job on the mangled
3283 names generated by current versions of g++. It also runs faster, so
3284 with this and other changes gdb should now start faster on large C++
3287 * DWARF 2 Location Expressions
3289 GDB support for location expressions has been extended to support function
3290 arguments and frame bases. Older versions of GDB could crash when they
3293 * C++ nested types and namespaces
3295 GDB's support for nested types and namespaces in C++ has been
3296 improved, especially if you use the DWARF 2 debugging format. (This
3297 is the default for recent versions of GCC on most platforms.)
3298 Specifically, if you have a class "Inner" defined within a class or
3299 namespace "Outer", then GDB realizes that the class's name is
3300 "Outer::Inner", not simply "Inner". This should greatly reduce the
3301 frequency of complaints about not finding RTTI symbols. In addition,
3302 if you are stopped at inside of a function defined within a namespace,
3303 GDB modifies its name lookup accordingly.
3305 * New native configurations
3307 NetBSD/amd64 x86_64-*-netbsd*
3308 OpenBSD/amd64 x86_64-*-openbsd*
3309 OpenBSD/alpha alpha*-*-openbsd*
3310 OpenBSD/sparc sparc-*-openbsd*
3311 OpenBSD/sparc64 sparc64-*-openbsd*
3313 * New debugging protocols
3315 M32R with SDI protocol m32r-*-elf*
3317 * "set prompt-escape-char" command deleted.
3319 The command "set prompt-escape-char" has been deleted. This command,
3320 and its very obscure effet on GDB's prompt, was never documented,
3321 tested, nor mentioned in the NEWS file.
3323 * OBSOLETE configurations and files
3325 Configurations that have been declared obsolete in this release have
3326 been commented out. Unless there is activity to revive these
3327 configurations, the next release of GDB will have their sources
3328 permanently REMOVED.
3330 Sun 3, running SunOS 3 m68*-*-sunos3*
3331 Sun 3, running SunOS 4 m68*-*-sunos4*
3332 Sun 2, running SunOS 3 m68000-*-sunos3*
3333 Sun 2, running SunOS 4 m68000-*-sunos4*
3334 Motorola 680x0 running LynxOS m68*-*-lynxos*
3335 AT&T 3b1/Unix pc m68*-att-*
3336 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3337 decstation mips-dec-* mips-little-*
3338 riscos mips-*-riscos* mips-*-sysv*
3339 sonymips mips-sony-*
3340 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3342 * REMOVED configurations and files
3344 SGI Irix-4.x mips-sgi-irix4 or iris4
3345 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3346 Z8000 simulator z8k-zilog-none or z8ksim
3347 Matsushita MN10200 w/simulator mn10200-*-*
3348 H8/500 simulator h8500-hitachi-hms or h8500hms
3349 HP/PA running BSD hppa*-*-bsd*
3350 HP/PA running OSF/1 hppa*-*-osf*
3351 HP/PA Pro target hppa*-*-pro*
3352 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3353 386BSD i[3456]86-*-bsd*
3354 Sequent family i[3456]86-sequent-sysv4*
3355 i[3456]86-sequent-sysv*
3356 i[3456]86-sequent-bsd*
3357 SPARC running LynxOS sparc-*-lynxos*
3358 SPARC running SunOS 4 sparc-*-sunos4*
3359 Tsqware Sparclet sparclet-*-*
3360 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3362 *** Changes in GDB 6.0:
3366 Support for debugging the Objective-C programming language has been
3367 integrated into GDB.
3369 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3371 DWARF 2's Call Frame Information makes available compiler generated
3372 information that more exactly describes the program's run-time stack.
3373 By using this information, GDB is able to provide more robust stack
3376 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3377 have been updated to use a new backtrace mechanism which includes
3378 DWARF 2 CFI support.
3382 GDB's remote protocol has been extended to include support for hosted
3383 file I/O (where the remote target uses GDB's file system). See GDB's
3384 remote protocol documentation for details.
3386 * All targets using the new architecture framework.
3388 All of GDB's targets have been updated to use the new internal
3389 architecture framework. The way is now open for future GDB releases
3390 to include cross-architecture native debugging support (i386 on amd64,
3393 * GNU/Linux's Thread Local Storage (TLS)
3395 GDB now includes support for for the GNU/Linux implementation of
3396 per-thread variables.
3398 * GNU/Linux's Native POSIX Thread Library (NPTL)
3400 GDB's thread code has been updated to work with either the new
3401 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3403 * Separate debug info.
3405 GDB, in conjunction with BINUTILS, now supports a mechanism for
3406 automatically loading debug information from a separate file. Instead
3407 of shipping full debug and non-debug versions of system libraries,
3408 system integrators can now instead ship just the stripped libraries
3409 and optional debug files.
3411 * DWARF 2 Location Expressions
3413 DWARF 2 Location Expressions allow the compiler to more completely
3414 describe the location of variables (even in optimized code) to the
3417 GDB now includes preliminary support for location expressions (support
3418 for DW_OP_piece is still missing).
3422 A number of long standing bugs that caused GDB to die while starting a
3423 Java application have been fixed. GDB's Java support is now
3424 considered "useable".
3426 * GNU/Linux support for fork, vfork, and exec.
3428 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3429 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3432 * GDB supports logging output to a file
3434 There are two new commands, "set logging" and "show logging", which can be
3435 used to capture GDB's output to a file.
3437 * The meaning of "detach" has changed for gdbserver
3439 The "detach" command will now resume the application, as documented. To
3440 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3443 * d10v, m68hc11 `regs' command deprecated
3445 The `info registers' command has been updated so that it displays the
3446 registers using a format identical to the old `regs' command.
3450 A new command, "maint set profile on/off", has been added. This command can
3451 be used to enable or disable profiling while running GDB, to profile a
3452 session or a set of commands. In addition there is a new configure switch,
3453 "--enable-profiling", which will cause GDB to be compiled with profiling
3454 data, for more informative profiling results.
3456 * Default MI syntax changed to "mi2".
3458 The default MI (machine interface) syntax, enabled by the command line
3459 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3460 "mi1", can be enabled by specifying the option "-i=mi1".
3462 Support for the original "mi0" syntax (included in GDB 5.0) has been
3465 Fix for gdb/192: removed extraneous space when displaying frame level.
3466 Fix for gdb/672: update changelist is now output in mi list format.
3467 Fix for gdb/702: a -var-assign that updates the value now shows up
3468 in a subsequent -var-update.
3470 * New native configurations.
3472 FreeBSD/amd64 x86_64-*-freebsd*
3474 * Multi-arched targets.
3476 HP/PA HPUX11 hppa*-*-hpux*
3477 Renesas M32R/D w/simulator m32r-*-elf*
3479 * OBSOLETE configurations and files
3481 Configurations that have been declared obsolete in this release have
3482 been commented out. Unless there is activity to revive these
3483 configurations, the next release of GDB will have their sources
3484 permanently REMOVED.
3486 Z8000 simulator z8k-zilog-none or z8ksim
3487 Matsushita MN10200 w/simulator mn10200-*-*
3488 H8/500 simulator h8500-hitachi-hms or h8500hms
3489 HP/PA running BSD hppa*-*-bsd*
3490 HP/PA running OSF/1 hppa*-*-osf*
3491 HP/PA Pro target hppa*-*-pro*
3492 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3493 Sequent family i[3456]86-sequent-sysv4*
3494 i[3456]86-sequent-sysv*
3495 i[3456]86-sequent-bsd*
3496 Tsqware Sparclet sparclet-*-*
3497 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3499 * REMOVED configurations and files
3502 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3503 IBM AIX PS/2 i[3456]86-*-aix
3504 i386 running Mach 3.0 i[3456]86-*-mach3*
3505 i386 running Mach i[3456]86-*-mach*
3506 i386 running OSF/1 i[3456]86-*osf1mk*
3507 HP/Apollo 68k Family m68*-apollo*-sysv*,
3509 m68*-hp-bsd*, m68*-hp-hpux*
3510 Argonaut Risc Chip (ARC) arc-*-*
3511 Mitsubishi D30V d30v-*-*
3512 Fujitsu FR30 fr30-*-elf*
3513 OS/9000 i[34]86-*-os9k
3514 I960 with MON960 i960-*-coff
3516 * MIPS $fp behavior changed
3518 The convenience variable $fp, for the MIPS, now consistently returns
3519 the address of the current frame's base. Previously, depending on the
3520 context, $fp could refer to either $sp or the current frame's base
3521 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3522 The GNU Source-Level Debugger''.
3524 *** Changes in GDB 5.3:
3526 * GNU/Linux shared library multi-threaded performance improved.
3528 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3529 `/proc', in preference to `ptrace' for memory reads. This may result
3530 in an improvement in the start-up time of multi-threaded, shared
3531 library applications when run under GDB. One GDB user writes: ``loads
3532 shared libs like mad''.
3534 * ``gdbserver'' now supports multi-threaded applications on some targets
3536 Support for debugging multi-threaded applications which use
3537 the GNU/Linux LinuxThreads package has been added for
3538 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3539 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3541 * GDB now supports C/C++ preprocessor macros.
3543 GDB now expands preprocessor macro invocations in C/C++ expressions,
3544 and provides various commands for showing macro definitions and how
3547 The new command `macro expand EXPRESSION' expands any macro
3548 invocations in expression, and shows the result.
3550 The new command `show macro MACRO-NAME' shows the definition of the
3551 macro named MACRO-NAME, and where it was defined.
3553 Most compilers don't include information about macros in the debugging
3554 information by default. In GCC 3.1, for example, you need to compile
3555 your program with the options `-gdwarf-2 -g3'. If the macro
3556 information is present in the executable, GDB will read it.
3558 * Multi-arched targets.
3560 DEC Alpha (partial) alpha*-*-*
3561 DEC VAX (partial) vax-*-*
3563 National Semiconductor NS32000 (partial) ns32k-*-*
3564 Motorola 68000 (partial) m68k-*-*
3565 Motorola MCORE mcore-*-*
3569 Fujitsu FRV architecture added by Red Hat frv*-*-*
3572 * New native configurations
3574 Alpha NetBSD alpha*-*-netbsd*
3575 SH NetBSD sh*-*-netbsdelf*
3576 MIPS NetBSD mips*-*-netbsd*
3577 UltraSPARC NetBSD sparc64-*-netbsd*
3579 * OBSOLETE configurations and files
3581 Configurations that have been declared obsolete in this release have
3582 been commented out. Unless there is activity to revive these
3583 configurations, the next release of GDB will have their sources
3584 permanently REMOVED.
3586 Mitsubishi D30V d30v-*-*
3587 OS/9000 i[34]86-*-os9k
3588 IBM AIX PS/2 i[3456]86-*-aix
3589 Fujitsu FR30 fr30-*-elf*
3590 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3591 Argonaut Risc Chip (ARC) arc-*-*
3592 i386 running Mach 3.0 i[3456]86-*-mach3*
3593 i386 running Mach i[3456]86-*-mach*
3594 i386 running OSF/1 i[3456]86-*osf1mk*
3595 HP/Apollo 68k Family m68*-apollo*-sysv*,
3597 m68*-hp-bsd*, m68*-hp-hpux*
3598 I960 with MON960 i960-*-coff
3600 * OBSOLETE languages
3602 CHILL, a Pascal like language used by telecommunications companies.
3604 * REMOVED configurations and files
3606 AMD 29k family via UDI a29k-amd-udi, udi29k
3607 A29K VxWorks a29k-*-vxworks
3608 AMD 29000 embedded, using EBMON a29k-none-none
3609 AMD 29000 embedded with COFF a29k-none-coff
3610 AMD 29000 embedded with a.out a29k-none-aout
3612 testsuite/gdb.hp/gdb.threads-hp/ directory
3614 * New command "set max-user-call-depth <nnn>"
3616 This command allows the user to limit the call depth of user-defined
3617 commands. The default is 1024.
3619 * Changes in FreeBSD/i386 native debugging.
3621 Support for the "generate-core-file" has been added.
3623 * New commands "dump", "append", and "restore".
3625 These commands allow data to be copied from target memory
3626 to a bfd-format or binary file (dump and append), and back
3627 from a file into memory (restore).
3629 * Improved "next/step" support on multi-processor Alpha Tru64.
3631 The previous single-step mechanism could cause unpredictable problems,
3632 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3633 of a software single-step mechanism prevents this.
3635 *** Changes in GDB 5.2.1:
3643 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3644 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3645 Fix, by Joel Brobecker imported from mainline.
3647 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3648 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3649 Fix, by Fred Fish, imported from mainline.
3651 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3652 Surprisingly enough, it works now.
3653 By Michal Ludvig, imported from mainline.
3655 i386 hardware watchpoint support:
3656 avoid misses on second run for some targets.
3657 By Pierre Muller, imported from mainline.
3659 *** Changes in GDB 5.2:
3661 * New command "set trust-readonly-sections on[off]".
3663 This command is a hint that tells gdb that read-only sections
3664 really are read-only (ie. that their contents will not change).
3665 In this mode, gdb will go to the object file rather than the
3666 target to read memory from read-only sections (such as ".text").
3667 This can be a significant performance improvement on some
3668 (notably embedded) targets.
3670 * New command "generate-core-file" (or "gcore").
3672 This new gdb command allows the user to drop a core file of the child
3673 process state at any time. So far it's been implemented only for
3674 GNU/Linux and Solaris, but should be relatively easily ported to other
3675 hosts. Argument is core file name (defaults to core.<pid>).
3677 * New command line option
3679 GDB now accepts --pid or -p followed by a process id.
3681 * Change in command line behavior -- corefiles vs. process ids.
3683 There is a subtle behavior in the way in which GDB handles
3684 command line arguments. The first non-flag argument is always
3685 a program to debug, but the second non-flag argument may either
3686 be a corefile or a process id. Previously, GDB would attempt to
3687 open the second argument as a corefile, and if that failed, would
3688 issue a superfluous error message and then attempt to attach it as
3689 a process. Now, if the second argument begins with a non-digit,
3690 it will be treated as a corefile. If it begins with a digit,
3691 GDB will attempt to attach it as a process, and if no such process
3692 is found, will then attempt to open it as a corefile.
3694 * Changes in ARM configurations.
3696 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3697 configuration is fully multi-arch.
3699 * New native configurations
3701 ARM NetBSD arm*-*-netbsd*
3702 x86 OpenBSD i[3456]86-*-openbsd*
3703 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3704 Sparc64 running FreeBSD sparc64-*-freebsd*
3708 Sanyo XStormy16 xstormy16-elf
3710 * OBSOLETE configurations and files
3712 Configurations that have been declared obsolete in this release have
3713 been commented out. Unless there is activity to revive these
3714 configurations, the next release of GDB will have their sources
3715 permanently REMOVED.
3717 AMD 29k family via UDI a29k-amd-udi, udi29k
3718 A29K VxWorks a29k-*-vxworks
3719 AMD 29000 embedded, using EBMON a29k-none-none
3720 AMD 29000 embedded with COFF a29k-none-coff
3721 AMD 29000 embedded with a.out a29k-none-aout
3723 testsuite/gdb.hp/gdb.threads-hp/ directory
3725 * REMOVED configurations and files
3727 TI TMS320C80 tic80-*-*
3729 PowerPC Solaris powerpcle-*-solaris*
3730 PowerPC Windows NT powerpcle-*-cygwin32
3731 PowerPC Netware powerpc-*-netware*
3732 Harris/CXUX m88k m88*-harris-cxux*
3733 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3734 ns32k-utek-sysv* ns32k-utek-*
3735 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3736 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3737 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3738 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3739 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3741 * Changes to command line processing
3743 The new `--args' feature can be used to specify command-line arguments
3744 for the inferior from gdb's command line.
3746 * Changes to key bindings
3748 There is a new `operate-and-get-next' function bound to `C-o'.
3750 *** Changes in GDB 5.1.1
3752 Fix compile problem on DJGPP.
3754 Fix a problem with floating-point registers on the i386 being
3757 Fix to stop GDB crashing on .debug_str debug info.
3759 Numerous documentation fixes.
3761 Numerous testsuite fixes.
3763 *** Changes in GDB 5.1:
3765 * New native configurations
3767 Alpha FreeBSD alpha*-*-freebsd*
3768 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3769 MIPS GNU/Linux mips*-*-linux*
3770 MIPS SGI Irix 6.x mips*-sgi-irix6*
3771 ia64 AIX ia64-*-aix*
3772 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3776 Motorola 68HC11 and 68HC12 m68hc11-elf
3778 UltraSparc running GNU/Linux sparc64-*-linux*
3780 * OBSOLETE configurations and files
3782 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3783 Harris/CXUX m88k m88*-harris-cxux*
3784 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3785 ns32k-utek-sysv* ns32k-utek-*
3786 TI TMS320C80 tic80-*-*
3788 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3789 PowerPC Solaris powerpcle-*-solaris*
3790 PowerPC Windows NT powerpcle-*-cygwin32
3791 PowerPC Netware powerpc-*-netware*
3792 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3793 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3794 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3795 Apple Macintosh (MPW) host N/A
3797 stuff.c (Program to stuff files into a specially prepared space in kdb)
3798 kdb-start.c (Main loop for the standalone kernel debugger)
3800 Configurations that have been declared obsolete in this release have
3801 been commented out. Unless there is activity to revive these
3802 configurations, the next release of GDB will have their sources
3803 permanently REMOVED.
3805 * REMOVED configurations and files
3807 Altos 3068 m68*-altos-*
3808 Convex c1-*-*, c2-*-*
3810 ARM RISCix arm-*-* (as host)
3814 * GDB has been converted to ISO C.
3816 GDB's source code has been converted to ISO C. In particular, the
3817 sources are fully protoized, and rely on standard headers being
3822 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3824 * The MI enabled by default.
3826 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3827 revised and enabled by default. Packages which use GDB as a debugging
3828 engine behind a UI or another front end are encouraged to switch to
3829 using the GDB/MI interface, instead of the old annotations interface
3830 which is now deprecated.
3832 * Support for debugging Pascal programs.
3834 GDB now includes support for debugging Pascal programs. The following
3835 main features are supported:
3837 - Pascal-specific data types such as sets;
3839 - automatic recognition of Pascal sources based on file-name
3842 - Pascal-style display of data types, variables, and functions;
3844 - a Pascal expression parser.
3846 However, some important features are not yet supported.
3848 - Pascal string operations are not supported at all;
3850 - there are some problems with boolean types;
3852 - Pascal type hexadecimal constants are not supported
3853 because they conflict with the internal variables format;
3855 - support for Pascal objects and classes is not full yet;
3857 - unlike Pascal, GDB is case-sensitive for symbol names.
3859 * Changes in completion.
3861 Commands such as `shell', `run' and `set args', which pass arguments
3862 to inferior programs, now complete on file names, similar to what
3863 users expect at the shell prompt.
3865 Commands which accept locations, such as `disassemble', `print',
3866 `breakpoint', `until', etc. now complete on filenames as well as
3867 program symbols. Thus, if you type "break foob TAB", and the source
3868 files linked into the programs include `foobar.c', that file name will
3869 be one of the candidates for completion. However, file names are not
3870 considered for completion after you typed a colon that delimits a file
3871 name from a name of a function in that file, as in "break foo.c:bar".
3873 `set demangle-style' completes on available demangling styles.
3875 * New platform-independent commands:
3877 It is now possible to define a post-hook for a command as well as a
3878 hook that runs before the command. For more details, see the
3879 documentation of `hookpost' in the GDB manual.
3881 * Changes in GNU/Linux native debugging.
3883 Support for debugging multi-threaded programs has been completely
3884 revised for all platforms except m68k and sparc. You can now debug as
3885 many threads as your system allows you to have.
3887 Attach/detach is supported for multi-threaded programs.
3889 Support for SSE registers was added for x86. This doesn't work for
3890 multi-threaded programs though.
3892 * Changes in MIPS configurations.
3894 Multi-arch support is enabled for all MIPS configurations.
3896 GDB can now be built as native debugger on SGI Irix 6.x systems for
3897 debugging n32 executables. (Debugging 64-bit executables is not yet
3900 * Unified support for hardware watchpoints in all x86 configurations.
3902 Most (if not all) native x86 configurations support hardware-assisted
3903 breakpoints and watchpoints in a unified manner. This support
3904 implements debug register sharing between watchpoints, which allows to
3905 put a virtually infinite number of watchpoints on the same address,
3906 and also supports watching regions up to 16 bytes with several debug
3909 The new maintenance command `maintenance show-debug-regs' toggles
3910 debugging print-outs in functions that insert, remove, and test
3911 watchpoints and hardware breakpoints.
3913 * Changes in the DJGPP native configuration.
3915 New command ``info dos sysinfo'' displays assorted information about
3916 the CPU, OS, memory, and DPMI server.
3918 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3919 display information about segment descriptors stored in GDT, LDT, and
3922 New commands ``info dos pde'' and ``info dos pte'' display entries
3923 from Page Directory and Page Tables (for now works with CWSDPMI only).
3924 New command ``info dos address-pte'' displays the Page Table entry for
3925 a given linear address.
3927 GDB can now pass command lines longer than 126 characters to the
3928 program being debugged (requires an update to the libdbg.a library
3929 which is part of the DJGPP development kit).
3931 DWARF2 debug info is now supported.
3933 It is now possible to `step' and `next' through calls to `longjmp'.
3935 * Changes in documentation.
3937 All GDB documentation was converted to GFDL, the GNU Free
3938 Documentation License.
3940 Tracepoints-related commands are now fully documented in the GDB
3943 TUI, the Text-mode User Interface, is now documented in the manual.
3945 Tracepoints-related commands are now fully documented in the GDB
3948 The "GDB Internals" manual now has an index. It also includes
3949 documentation of `ui_out' functions, GDB coding standards, x86
3950 hardware watchpoints, and memory region attributes.
3952 * GDB's version number moved to ``version.in''
3954 The Makefile variable VERSION has been replaced by the file
3955 ``version.in''. People creating GDB distributions should update the
3956 contents of this file.
3960 GUD support is now a standard part of the EMACS distribution.
3962 *** Changes in GDB 5.0:
3964 * Improved support for debugging FP programs on x86 targets
3966 Unified and much-improved support for debugging floating-point
3967 programs on all x86 targets. In particular, ``info float'' now
3968 displays the FP registers in the same format on all x86 targets, with
3969 greater level of detail.
3971 * Improvements and bugfixes in hardware-assisted watchpoints
3973 It is now possible to watch array elements, struct members, and
3974 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3975 on x86 targets no longer erroneously trigger when the address is
3978 * Improvements in the native DJGPP version of GDB
3980 The distribution now includes all the scripts and auxiliary files
3981 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3982 machines ``out of the box''.
3984 The DJGPP version can now debug programs that use signals. It is
3985 possible to catch signals that happened in the debuggee, deliver
3986 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3987 would kill the program being debugged.) Programs that hook hardware
3988 interrupts (keyboard, timer, etc.) can also be debugged.
3990 It is now possible to debug DJGPP programs that redirect their
3991 standard handles or switch them to raw (as opposed to cooked) mode, or
3992 even close them. The command ``run < foo > bar'' works as expected,
3993 and ``info terminal'' reports useful information about the debuggee's
3994 terminal, including raw/cooked mode, redirection, etc.
3996 The DJGPP version now uses termios functions for console I/O, which
3997 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4000 DOS-style file names with drive letters are now fully supported by
4003 It is now possible to debug DJGPP programs that switch their working
4004 directory. It is also possible to rerun the debuggee any number of
4005 times without restarting GDB; thus, you can use the same setup,
4006 breakpoints, etc. for many debugging sessions.
4008 * New native configurations
4010 ARM GNU/Linux arm*-*-linux*
4011 PowerPC GNU/Linux powerpc-*-linux*
4015 Motorola MCore mcore-*-*
4016 x86 VxWorks i[3456]86-*-vxworks*
4017 PowerPC VxWorks powerpc-*-vxworks*
4018 TI TMS320C80 tic80-*-*
4020 * OBSOLETE configurations
4022 Altos 3068 m68*-altos-*
4023 Convex c1-*-*, c2-*-*
4025 ARM RISCix arm-*-* (as host)
4028 Configurations that have been declared obsolete will be commented out,
4029 but the code will be left in place. If there is no activity to revive
4030 these configurations before the next release of GDB, the sources will
4031 be permanently REMOVED.
4033 * Gould support removed
4035 Support for the Gould PowerNode and NP1 has been removed.
4037 * New features for SVR4
4039 On SVR4 native platforms (such as Solaris), if you attach to a process
4040 without first loading a symbol file, GDB will now attempt to locate and
4041 load symbols from the running process's executable file.
4043 * Many C++ enhancements
4045 C++ support has been greatly improved. Overload resolution now works properly
4046 in almost all cases. RTTI support is on the way.
4048 * Remote targets can connect to a sub-program
4050 A popen(3) style serial-device has been added. This device starts a
4051 sub-process (such as a stand-alone simulator) and then communicates
4052 with that. The sub-program to run is specified using the syntax
4053 ``|<program> <args>'' vis:
4055 (gdb) set remotedebug 1
4056 (gdb) target extended-remote |mn10300-elf-sim program-args
4058 * MIPS 64 remote protocol
4060 A long standing bug in the mips64 remote protocol where by GDB
4061 expected certain 32 bit registers (ex SR) to be transfered as 32
4062 instead of 64 bits has been fixed.
4064 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4065 added to provide backward compatibility with older versions of GDB.
4067 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4069 The command ``set remotebinarydownload'' command has been replaced by
4070 ``set remote X-packet''. Other commands in ``set remote'' family
4071 include ``set remote P-packet''.
4073 * Breakpoint commands accept ranges.
4075 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4076 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4077 ``tracepoint passcount'' also accepts a range of tracepoints.
4079 * ``apropos'' command added.
4081 The ``apropos'' command searches through command names and
4082 documentation strings, printing out matches, making it much easier to
4083 try to find a command that does what you are looking for.
4087 A new machine oriented interface (MI) has been added to GDB. This
4088 interface is designed for debug environments running GDB as a separate
4089 process. This is part of the long term libGDB project. See the
4090 "GDB/MI" chapter of the GDB manual for further information. It can be
4091 enabled by configuring with:
4093 .../configure --enable-gdbmi
4095 *** Changes in GDB-4.18:
4097 * New native configurations
4099 HP-UX 10.20 hppa*-*-hpux10.20
4100 HP-UX 11.x hppa*-*-hpux11.0*
4101 M68K GNU/Linux m68*-*-linux*
4105 Fujitsu FR30 fr30-*-elf*
4106 Intel StrongARM strongarm-*-*
4107 Mitsubishi D30V d30v-*-*
4109 * OBSOLETE configurations
4111 Gould PowerNode, NP1 np1-*-*, pn-*-*
4113 Configurations that have been declared obsolete will be commented out,
4114 but the code will be left in place. If there is no activity to revive
4115 these configurations before the next release of GDB, the sources will
4116 be permanently REMOVED.
4120 As a compatibility experiment, GDB's source files buildsym.h and
4121 buildsym.c have been converted to pure standard C, no longer
4122 containing any K&R compatibility code. We believe that all systems in
4123 use today either come with a standard C compiler, or have a GCC port
4124 available. If this is not true, please report the affected
4125 configuration to bug-gdb@gnu.org immediately. See the README file for
4126 information about getting a standard C compiler if you don't have one
4131 GDB now uses readline 2.2.
4133 * set extension-language
4135 You can now control the mapping between filename extensions and source
4136 languages by using the `set extension-language' command. For instance,
4137 you can ask GDB to treat .c files as C++ by saying
4138 set extension-language .c c++
4139 The command `info extensions' lists all of the recognized extensions
4140 and their associated languages.
4142 * Setting processor type for PowerPC and RS/6000
4144 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4145 you can use the `set processor' command to specify what variant of the
4146 PowerPC family you are debugging. The command
4150 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4151 following PowerPC and RS6000 variants:
4153 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4154 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4156 403GC IBM PowerPC 403GC
4157 505 Motorola PowerPC 505
4158 860 Motorola PowerPC 860 or 850
4159 601 Motorola PowerPC 601
4160 602 Motorola PowerPC 602
4161 603 Motorola/IBM PowerPC 603 or 603e
4162 604 Motorola PowerPC 604 or 604e
4163 750 Motorola/IBM PowerPC 750 or 750
4165 At the moment, this command just tells GDB what to name the
4166 special-purpose processor registers. Since almost all the affected
4167 registers are inaccessible to user-level programs, this command is
4168 only useful for remote debugging in its present form.
4172 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4173 more extensive support for HP-UX. Added features include shared
4174 library support, kernel threads and hardware watchpoints for 11.00,
4175 support for HP's ANSI C and C++ compilers, and a compatibility mode
4176 for xdb and dbx commands.
4180 HP's donation includes the new concept of catchpoints, which is a
4181 generalization of the old catch command. On HP-UX, it is now possible
4182 to catch exec, fork, and vfork, as well as library loading.
4184 This means that the existing catch command has changed; its first
4185 argument now specifies the type of catch to be set up. See the
4186 output of "help catch" for a list of catchpoint types.
4188 * Debugging across forks
4190 On HP-UX, you can choose which process to debug when a fork() happens
4195 HP has donated a curses-based terminal user interface (TUI). To get
4196 it, build with --enable-tui. Although this can be enabled for any
4197 configuration, at present it only works for native HP debugging.
4199 * GDB remote protocol additions
4201 A new protocol packet 'X' that writes binary data is now available.
4202 Default behavior is to try 'X', then drop back to 'M' if the stub
4203 fails to respond. The settable variable `remotebinarydownload'
4204 allows explicit control over the use of 'X'.
4206 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4207 full 64-bit address. The command
4209 set remoteaddresssize 32
4211 can be used to revert to the old behaviour. For existing remote stubs
4212 the change should not be noticed, as the additional address information
4215 In order to assist in debugging stubs, you may use the maintenance
4216 command `packet' to send any text string to the stub. For instance,
4218 maint packet heythere
4220 sends the packet "$heythere#<checksum>". Note that it is very easy to
4221 disrupt a debugging session by sending the wrong packet at the wrong
4224 The compare-sections command allows you to compare section data on the
4225 target to what is in the executable file without uploading or
4226 downloading, by comparing CRC checksums.
4228 * Tracing can collect general expressions
4230 You may now collect general expressions at tracepoints. This requires
4231 further additions to the target-side stub; see tracepoint.c and
4232 doc/agentexpr.texi for further details.
4234 * mask-address variable for Mips
4236 For Mips targets, you may control the zeroing of the upper 32 bits of
4237 a 64-bit address by entering `set mask-address on'. This is mainly
4238 of interest to users of embedded R4xxx and R5xxx processors.
4240 * Higher serial baud rates
4242 GDB's serial code now allows you to specify baud rates 57600, 115200,
4243 230400, and 460800 baud. (Note that your host system may not be able
4244 to achieve all of these rates.)
4248 The i960 configuration now includes an initial implementation of a
4249 builtin simulator, contributed by Jim Wilson.
4252 *** Changes in GDB-4.17:
4254 * New native configurations
4256 Alpha GNU/Linux alpha*-*-linux*
4257 Unixware 2.x i[3456]86-unixware2*
4258 Irix 6.x mips*-sgi-irix6*
4259 PowerPC GNU/Linux powerpc-*-linux*
4260 PowerPC Solaris powerpcle-*-solaris*
4261 Sparc GNU/Linux sparc-*-linux*
4262 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4266 Argonaut Risc Chip (ARC) arc-*-*
4267 Hitachi H8/300S h8300*-*-*
4268 Matsushita MN10200 w/simulator mn10200-*-*
4269 Matsushita MN10300 w/simulator mn10300-*-*
4270 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4271 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4272 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4273 Mitsubishi D10V w/simulator d10v-*-*
4274 Mitsubishi M32R/D w/simulator m32r-*-elf*
4275 Tsqware Sparclet sparclet-*-*
4276 NEC V850 w/simulator v850-*-*
4278 * New debugging protocols
4280 ARM with RDI protocol arm*-*-*
4281 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4282 DDB and LSI variants of PMON protocol mips*-*-*
4283 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4284 PowerPC with SDS protocol powerpc{,le}-*-eabi
4285 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4289 All configurations can now understand and use the DWARF 2 debugging
4290 format. The choice is automatic, if the symbol file contains DWARF 2
4295 GDB now includes basic Java language support. This support is
4296 only useful with Java compilers that produce native machine code.
4298 * solib-absolute-prefix and solib-search-path
4300 For SunOS and SVR4 shared libraries, you may now set the prefix for
4301 loading absolute shared library symbol files, and the search path for
4302 locating non-absolute shared library symbol files.
4304 * Live range splitting
4306 GDB can now effectively debug code for which GCC has performed live
4307 range splitting as part of its optimization. See gdb/doc/LRS for
4308 more details on the expected format of the stabs information.
4312 GDB's support for the GNU Hurd, including thread debugging, has been
4313 updated to work with current versions of the Hurd.
4317 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4318 instruction set. ARM GDB automatically detects when Thumb
4319 instructions are in use, and adjusts disassembly and backtracing
4324 GDB's MIPS target configurations now handle the MIP16 16-bit
4329 GDB now includes support for overlays; if an executable has been
4330 linked such that multiple sections are based at the same address, GDB
4331 will decide which section to use for symbolic info. You can choose to
4332 control the decision manually, using overlay commands, or implement
4333 additional target-side support and use "overlay load-target" to bring
4334 in the overlay mapping. Do "help overlay" for more detail.
4338 The command "info symbol <address>" displays information about
4339 the symbol at the specified address.
4343 The standard remote protocol now includes an extension that allows
4344 asynchronous collection and display of trace data. This requires
4345 extensive support in the target-side debugging stub. Tracing mode
4346 includes a new interaction mode in GDB and new commands: see the
4347 file tracepoint.c for more details.
4351 Configurations for embedded MIPS now include a simulator contributed
4352 by Cygnus Solutions. The simulator supports the instruction sets
4353 of most MIPS variants.
4357 Sparc configurations may now include the ERC32 simulator contributed
4358 by the European Space Agency. The simulator is not built into
4359 Sparc targets by default; configure with --enable-sim to include it.
4363 For target configurations that may include multiple variants of a
4364 basic architecture (such as MIPS and SH), you may now set the
4365 architecture explicitly. "set arch" sets, "info arch" lists
4366 the possible architectures.
4368 *** Changes in GDB-4.16:
4370 * New native configurations
4372 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4373 M68K NetBSD m68k-*-netbsd*
4374 PowerPC AIX 4.x powerpc-*-aix*
4375 PowerPC MacOS powerpc-*-macos*
4376 PowerPC Windows NT powerpcle-*-cygwin32
4377 RS/6000 AIX 4.x rs6000-*-aix4*
4381 ARM with RDP protocol arm-*-*
4382 I960 with MON960 i960-*-coff
4383 MIPS VxWorks mips*-*-vxworks*
4384 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4385 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4387 Matra Sparclet sparclet-*-*
4391 The powerpc-eabi configuration now includes the PSIM simulator,
4392 contributed by Andrew Cagney, with assistance from Mike Meissner.
4393 PSIM is a very elaborate model of the PowerPC, including not only
4394 basic instruction set execution, but also details of execution unit
4395 performance and I/O hardware. See sim/ppc/README for more details.
4399 GDB now works with Solaris 2.5.
4401 * Windows 95/NT native
4403 GDB will now work as a native debugger on Windows 95 and Windows NT.
4404 To build it from source, you must use the "gnu-win32" environment,
4405 which uses a DLL to emulate enough of Unix to run the GNU tools.
4406 Further information, binaries, and sources are available at
4407 ftp.cygnus.com, under pub/gnu-win32.
4409 * dont-repeat command
4411 If a user-defined command includes the command `dont-repeat', then the
4412 command will not be repeated if the user just types return. This is
4413 useful if the command is time-consuming to run, so that accidental
4414 extra keystrokes don't run the same command many times.
4416 * Send break instead of ^C
4418 The standard remote protocol now includes an option to send a break
4419 rather than a ^C to the target in order to interrupt it. By default,
4420 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4422 * Remote protocol timeout
4424 The standard remote protocol includes a new variable `remotetimeout'
4425 that allows you to set the number of seconds before GDB gives up trying
4426 to read from the target. The default value is 2.
4428 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4430 By default GDB will automatically keep track of objects as they are
4431 loaded and unloaded by the dynamic linker. By using the command `set
4432 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4433 when shared library events occur, thus allowing you to set breakpoints
4434 in shared libraries which are explicitly loaded by the inferior.
4436 Note this feature does not work on hpux8. On hpux9 you must link
4437 /usr/lib/end.o into your program. This feature should work
4438 automatically on hpux10.
4440 * Irix 5.x hardware watchpoint support
4442 Irix 5 configurations now support the use of hardware watchpoints.
4444 * Mips protocol "SYN garbage limit"
4446 When debugging a Mips target using the `target mips' protocol, you
4447 may set the number of characters that GDB will ignore by setting
4448 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4449 every character. The default value is 1050.
4451 * Recording and replaying remote debug sessions
4453 If you set `remotelogfile' to the name of a file, gdb will write to it
4454 a recording of a remote debug session. This recording may then be
4455 replayed back to gdb using "gdbreplay". See gdbserver/README for
4456 details. This is useful when you have a problem with GDB while doing
4457 remote debugging; you can make a recording of the session and send it
4458 to someone else, who can then recreate the problem.
4460 * Speedups for remote debugging
4462 GDB includes speedups for downloading and stepping MIPS systems using
4463 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4464 and more efficient S-record downloading.
4466 * Memory use reductions and statistics collection
4468 GDB now uses less memory and reports statistics about memory usage.
4469 Try the `maint print statistics' command, for example.
4471 *** Changes in GDB-4.15:
4473 * Psymtabs for XCOFF
4475 The symbol reader for AIX GDB now uses partial symbol tables. This
4476 can greatly improve startup time, especially for large executables.
4478 * Remote targets use caching
4480 Remote targets now use a data cache to speed up communication with the
4481 remote side. The data cache could lead to incorrect results because
4482 it doesn't know about volatile variables, thus making it impossible to
4483 debug targets which use memory mapped I/O devices. `set remotecache
4484 off' turns the the data cache off.
4486 * Remote targets may have threads
4488 The standard remote protocol now includes support for multiple threads
4489 in the target system, using new protocol commands 'H' and 'T'. See
4490 gdb/remote.c for details.
4494 If GDB is configured with `--enable-netrom', then it will include
4495 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4496 acts as though it is a bank of ROM on the target board, but you can
4497 write into it over the network. GDB's support consists only of
4498 support for fast loading into the emulated ROM; to debug, you must use
4499 another protocol, such as standard remote protocol. The usual
4500 sequence is something like
4502 target nrom <netrom-hostname>
4504 target remote <netrom-hostname>:1235
4508 GDB now includes support for the Apple Macintosh, as a host only. It
4509 may be run as either an MPW tool or as a standalone application, and
4510 it can debug through the serial port. All the usual GDB commands are
4511 available, but to the target command, you must supply "serial" as the
4512 device type instead of "/dev/ttyXX". See mpw-README in the main
4513 directory for more information on how to build. The MPW configuration
4514 scripts */mpw-config.in support only a few targets, and only the
4515 mips-idt-ecoff target has been tested.
4519 GDB configuration now uses autoconf. This is not user-visible,
4520 but does simplify configuration and building.
4524 GDB now supports hpux10.
4526 *** Changes in GDB-4.14:
4528 * New native configurations
4530 x86 FreeBSD i[345]86-*-freebsd
4531 x86 NetBSD i[345]86-*-netbsd
4532 NS32k NetBSD ns32k-*-netbsd
4533 Sparc NetBSD sparc-*-netbsd
4537 A29K VxWorks a29k-*-vxworks
4538 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4539 CPU32 EST-300 emulator m68*-*-est*
4540 PowerPC ELF powerpc-*-elf
4543 * Alpha OSF/1 support for procfs
4545 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4546 possible to attach to running processes. As the mounting of the /proc
4547 filesystem is optional on the Alpha, GDB automatically determines
4548 the availability of /proc during startup. This can lead to problems
4549 if /proc is unmounted after GDB has been started.
4551 * Arguments to user-defined commands
4553 User commands may accept up to 10 arguments separated by whitespace.
4554 Arguments are accessed within the user command via $arg0..$arg9. A
4557 print $arg0 + $arg1 + $arg2
4559 To execute the command use:
4562 Defines the command "adder" which prints the sum of its three arguments.
4563 Note the arguments are text substitutions, so they may reference variables,
4564 use complex expressions, or even perform inferior function calls.
4566 * New `if' and `while' commands
4568 This makes it possible to write more sophisticated user-defined
4569 commands. Both commands take a single argument, which is the
4570 expression to evaluate, and must be followed by the commands to
4571 execute, one per line, if the expression is nonzero, the list being
4572 terminated by the word `end'. The `if' command list may include an
4573 `else' word, which causes the following commands to be executed only
4574 if the expression is zero.
4576 * Fortran source language mode
4578 GDB now includes partial support for Fortran 77. It will recognize
4579 Fortran programs and can evaluate a subset of Fortran expressions, but
4580 variables and functions may not be handled correctly. GDB will work
4581 with G77, but does not yet know much about symbols emitted by other
4584 * Better HPUX support
4586 Most debugging facilities now work on dynamic executables for HPPAs
4587 running hpux9 or later. You can attach to running dynamically linked
4588 processes, but by default the dynamic libraries will be read-only, so
4589 for instance you won't be able to put breakpoints in them. To change
4590 that behavior do the following before running the program:
4596 This will cause the libraries to be mapped private and read-write.
4597 To revert to the normal behavior, do this:
4603 You cannot set breakpoints or examine data in the library until after
4604 the library is loaded if the function/data symbols do not have
4607 GDB can now also read debug symbols produced by the HP C compiler on
4608 HPPAs (sorry, no C++, Fortran or 68k support).
4610 * Target byte order now dynamically selectable
4612 You can choose which byte order to use with a target system, via the
4613 commands "set endian big" and "set endian little", and you can see the
4614 current setting by using "show endian". You can also give the command
4615 "set endian auto", in which case GDB will use the byte order
4616 associated with the executable. Currently, only embedded MIPS
4617 configurations support dynamic selection of target byte order.
4619 * New DOS host serial code
4621 This version uses DPMI interrupts to handle buffered I/O, so you
4622 no longer need to run asynctsr when debugging boards connected to
4625 *** Changes in GDB-4.13:
4627 * New "complete" command
4629 This lists all the possible completions for the rest of the line, if it
4630 were to be given as a command itself. This is intended for use by emacs.
4632 * Trailing space optional in prompt
4634 "set prompt" no longer adds a space for you after the prompt you set. This
4635 allows you to set a prompt which ends in a space or one that does not.
4637 * Breakpoint hit counts
4639 "info break" now displays a count of the number of times the breakpoint
4640 has been hit. This is especially useful in conjunction with "ignore"; you
4641 can ignore a large number of breakpoint hits, look at the breakpoint info
4642 to see how many times the breakpoint was hit, then run again, ignoring one
4643 less than that number, and this will get you quickly to the last hit of
4646 * Ability to stop printing at NULL character
4648 "set print null-stop" will cause GDB to stop printing the characters of
4649 an array when the first NULL is encountered. This is useful when large
4650 arrays actually contain only short strings.
4652 * Shared library breakpoints
4654 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4655 breakpoints in shared libraries before the executable is run.
4657 * Hardware watchpoints
4659 There is a new hardware breakpoint for the watch command for sparclite
4660 targets. See gdb/sparclite/hw_breakpoint.note.
4662 Hardware watchpoints are also now supported under GNU/Linux.
4666 Annotations have been added. These are for use with graphical interfaces,
4667 and are still experimental. Currently only gdba.el uses these.
4669 * Improved Irix 5 support
4671 GDB now works properly with Irix 5.2.
4673 * Improved HPPA support
4675 GDB now works properly with the latest GCC and GAS.
4677 * New native configurations
4679 Sequent PTX4 i[34]86-sequent-ptx4
4680 HPPA running OSF/1 hppa*-*-osf*
4681 Atari TT running SVR4 m68*-*-sysv4*
4682 RS/6000 LynxOS rs6000-*-lynxos*
4686 OS/9000 i[34]86-*-os9k
4687 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4690 * Hitachi SH7000 and E7000-PC ICE support
4692 There is now support for communicating with the Hitachi E7000-PC ICE.
4693 This is available automatically when GDB is configured for the SH.
4697 As usual, a variety of small fixes and improvements, both generic
4698 and configuration-specific. See the ChangeLog for more detail.
4700 *** Changes in GDB-4.12:
4702 * Irix 5 is now supported
4706 GDB-4.12 on the HPPA has a number of changes which make it unable
4707 to debug the output from the currently released versions of GCC and
4708 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4709 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4710 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4713 *** Changes in GDB-4.11:
4715 * User visible changes:
4719 The "set remotedebug" option is now consistent between the mips remote
4720 target, remote targets using the gdb-specific protocol, UDI (AMD's
4721 debug protocol for the 29k) and the 88k bug monitor. It is now an
4722 integer specifying a debug level (normally 0 or 1, but 2 means more
4723 debugging info for the mips target).
4725 * DEC Alpha native support
4727 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4728 debug info, but GDB works fairly well with the DEC compiler and should
4729 work with a future GCC release. See the README file for a few
4730 Alpha-specific notes.
4732 * Preliminary thread implementation
4734 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4736 * LynxOS native and target support for 386
4738 This release has been hosted on LynxOS 2.2, and also can be configured
4739 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4742 * Improvements in C++ mangling/demangling.
4744 This release has much better g++ debugging, specifically in name
4745 mangling/demangling, virtual function calls, print virtual table,
4746 call methods, ...etc.
4748 *** Changes in GDB-4.10:
4750 * User visible changes:
4752 Remote debugging using the GDB-specific (`target remote') protocol now
4753 supports the `load' command. This is only useful if you have some
4754 other way of getting the stub to the target system, and you can put it
4755 somewhere in memory where it won't get clobbered by the download.
4757 Filename completion now works.
4759 When run under emacs mode, the "info line" command now causes the
4760 arrow to point to the line specified. Also, "info line" prints
4761 addresses in symbolic form (as well as hex).
4763 All vxworks based targets now support a user settable option, called
4764 vxworks-timeout. This option represents the number of seconds gdb
4765 should wait for responses to rpc's. You might want to use this if
4766 your vxworks target is, perhaps, a slow software simulator or happens
4767 to be on the far side of a thin network line.
4771 This release contains support for using a DEC alpha as a GDB host for
4772 cross debugging. Native alpha debugging is not supported yet.
4775 *** Changes in GDB-4.9:
4779 This is the first GDB release which is accompanied by a matching testsuite.
4780 The testsuite requires installation of dejagnu, which should be available
4781 via ftp from most sites that carry GNU software.
4785 'Cfront' style demangling has had its name changed to 'ARM' style, to
4786 emphasize that it was written from the specifications in the C++ Annotated
4787 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4788 disclaimers, it still generated too much confusion with users attempting to
4789 use gdb with AT&T cfront.
4793 GDB now uses a standard remote interface to a simulator library.
4794 So far, the library contains simulators for the Zilog Z8001/2, the
4795 Hitachi H8/300, H8/500 and Super-H.
4797 * New targets supported
4799 H8/300 simulator h8300-hitachi-hms or h8300hms
4800 H8/500 simulator h8500-hitachi-hms or h8500hms
4801 SH simulator sh-hitachi-hms or sh
4802 Z8000 simulator z8k-zilog-none or z8ksim
4803 IDT MIPS board over serial line mips-idt-ecoff
4805 Cross-debugging to GO32 targets is supported. It requires a custom
4806 version of the i386-stub.c module which is integrated with the
4807 GO32 memory extender.
4809 * New remote protocols
4811 MIPS remote debugging protocol.
4813 * New source languages supported
4815 This version includes preliminary support for Chill, a Pascal like language
4816 used by telecommunications companies. Chill support is also being integrated
4817 into the GNU compiler, but we don't know when it will be publically available.
4820 *** Changes in GDB-4.8:
4822 * HP Precision Architecture supported
4824 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4825 version of this support was available as a set of patches from the
4826 University of Utah. GDB does not support debugging of programs
4827 compiled with the HP compiler, because HP will not document their file
4828 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4829 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4831 Many problems in the preliminary version have been fixed.
4833 * Faster and better demangling
4835 We have improved template demangling and fixed numerous bugs in the GNU style
4836 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4837 character types (wchar_t) are now supported. Demangling of each symbol is now
4838 only done once, and is cached when the symbol table for a file is read in.
4839 This results in a small increase in memory usage for C programs, a moderate
4840 increase in memory usage for C++ programs, and a fantastic speedup in
4843 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4844 from the specifications in the Annotated Reference Manual, which AT&T's
4845 compiler does not actually implement.
4847 * G++ multiple inheritance compiler problem
4849 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4850 inheritance lattices was reworked to properly discover ambiguities. We
4851 recently found an example which causes this new algorithm to fail in a
4852 very subtle way, producing bad debug information for those classes.
4853 The file 'gcc.patch' (in this directory) can be applied to gcc to
4854 circumvent the problem. A future GCC release will contain a complete
4857 The previous G++ debug info problem (mentioned below for the gdb-4.7
4858 release) is fixed in gcc version 2.3.2.
4860 * Improved configure script
4862 The `configure' script will now attempt to guess your system type if
4863 you don't supply a host system type. The old scheme of supplying a
4864 host system triplet is preferable over using this. All the magic is
4865 done in the new `config.guess' script. Examine it for details.
4867 We have also brought our configure script much more in line with the FSF's
4868 version. It now supports the --with-xxx options. In particular,
4869 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4870 The resulting GDB will not be able to read arbitrary object file formats --
4871 only the format ``expected'' to be used on the configured target system.
4872 We hope to make this the default in a future release.
4874 * Documentation improvements
4876 There's new internal documentation on how to modify GDB, and how to
4877 produce clean changes to the code. We implore people to read it
4878 before submitting changes.
4880 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4881 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4882 `info' files are also provided. To build `info' files from scratch,
4883 you will need the latest `makeinfo' release, which will be available in
4884 a future texinfo-X.Y release.
4886 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4887 We're not sure exactly which versions have this problem, but it has
4888 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4889 or better. If that isn't possible, there is a patch in
4890 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4891 around this problem.
4895 GDB now supports array constants that can be used in expressions typed in by
4896 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4897 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4900 The new directory `gdb/sparclite' contains a program that demonstrates
4901 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4903 * New native hosts supported
4905 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4906 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4908 * New targets supported
4910 AMD 29k family via UDI a29k-amd-udi or udi29k
4912 * New file formats supported
4914 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4915 HPUX core files, and SCO 3.2v2 core files.
4919 Attaching to processes now works again; thanks for the many bug reports.
4921 We have also stomped on a bunch of core dumps caused by
4922 printf_filtered("%s") problems.
4924 We eliminated a copyright problem on the rpc and ptrace header files
4925 for VxWorks, which was discovered at the last minute during the 4.7
4926 release. You should now be able to build a VxWorks GDB.
4928 You can now interrupt gdb while an attached process is running. This
4929 will cause the attached process to stop, and give control back to GDB.
4931 We fixed problems caused by using too many file descriptors
4932 for reading symbols from object files and libraries. This was
4933 especially a problem for programs that used many (~100) shared
4936 The `step' command now only enters a subroutine if there is line number
4937 information for the subroutine. Otherwise it acts like the `next'
4938 command. Previously, `step' would enter subroutines if there was
4939 any debugging information about the routine. This avoids problems
4940 when using `cc -g1' on MIPS machines.
4942 * Internal improvements
4944 GDB's internal interfaces have been improved to make it easier to support
4945 debugging of multiple languages in the future.
4947 GDB now uses a common structure for symbol information internally.
4948 Minimal symbols (derived from linkage symbols in object files), partial
4949 symbols (from a quick scan of debug information), and full symbols
4950 contain a common subset of information, making it easier to write
4951 shared code that handles any of them.
4953 * New command line options
4955 We now accept --silent as an alias for --quiet.
4959 The memory-mapped-malloc library is now licensed under the GNU Library
4960 General Public License.
4962 *** Changes in GDB-4.7:
4964 * Host/native/target split
4966 GDB has had some major internal surgery to untangle the support for
4967 hosts and remote targets. Now, when you configure GDB for a remote
4968 target, it will no longer load in all of the support for debugging
4969 local programs on the host. When fully completed and tested, this will
4970 ensure that arbitrary host/target combinations are possible.
4972 The primary conceptual shift is to separate the non-portable code in
4973 GDB into three categories. Host specific code is required any time GDB
4974 is compiled on that host, regardless of the target. Target specific
4975 code relates to the peculiarities of the target, but can be compiled on
4976 any host. Native specific code is everything else: it can only be
4977 built when the host and target are the same system. Child process
4978 handling and core file support are two common `native' examples.
4980 GDB's use of /proc for controlling Unix child processes is now cleaner.
4981 It has been split out into a single module under the `target_ops' vector,
4982 plus two native-dependent functions for each system that uses /proc.
4984 * New hosts supported
4986 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4987 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4988 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4990 * New targets supported
4992 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4993 68030 and CPU32 m68030-*-*, m68332-*-*
4995 * New native hosts supported
4997 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4998 (386bsd is not well tested yet)
4999 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5001 * New file formats supported
5003 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5004 supports reading of `a.out.adobe' object files, which are an a.out
5005 format extended with minimal information about multiple sections.
5009 `show copying' is the same as the old `info copying'.
5010 `show warranty' is the same as `info warrantee'.
5011 These were renamed for consistency. The old commands continue to work.
5013 `info handle' is a new alias for `info signals'.
5015 You can now define pre-command hooks, which attach arbitrary command
5016 scripts to any command. The commands in the hook will be executed
5017 prior to the user's command. You can also create a hook which will be
5018 executed whenever the program stops. See gdb.texinfo.
5022 We now deal with Cfront style name mangling, and can even extract type
5023 info from mangled symbols. GDB can automatically figure out which
5024 symbol mangling style your C++ compiler uses.
5026 Calling of methods and virtual functions has been improved as well.
5030 The crash that occured when debugging Sun Ansi-C compiled binaries is
5031 fixed. This was due to mishandling of the extra N_SO stabs output
5034 We also finally got Ultrix 4.2 running in house, and fixed core file
5035 support, with help from a dozen people on the net.
5037 John M. Farrell discovered that the reason that single-stepping was so
5038 slow on all of the Mips based platforms (primarily SGI and DEC) was
5039 that we were trying to demangle and lookup a symbol used for internal
5040 purposes on every instruction that was being stepped through. Changing
5041 the name of that symbol so that it couldn't be mistaken for a C++
5042 mangled symbol sped things up a great deal.
5044 Rich Pixley sped up symbol lookups in general by getting much smarter
5045 about when C++ symbol mangling is necessary. This should make symbol
5046 completion (TAB on the command line) much faster. It's not as fast as
5047 we'd like, but it's significantly faster than gdb-4.6.
5051 A new user controllable variable 'call_scratch_address' can
5052 specify the location of a scratch area to be used when GDB
5053 calls a function in the target. This is necessary because the
5054 usual method of putting the scratch area on the stack does not work
5055 in systems that have separate instruction and data spaces.
5057 We integrated changes to support the 29k UDI (Universal Debugger
5058 Interface), but discovered at the last minute that we didn't have all
5059 of the appropriate copyright paperwork. We are working with AMD to
5060 resolve this, and hope to have it available soon.
5064 We have sped up the remote serial line protocol, especially for targets
5065 with lots of registers. It now supports a new `expedited status' ('T')
5066 message which can be used in place of the existing 'S' status message.
5067 This allows the remote stub to send only the registers that GDB
5068 needs to make a quick decision about single-stepping or conditional
5069 breakpoints, eliminating the need to fetch the entire register set for
5070 each instruction being stepped through.
5072 The GDB remote serial protocol now implements a write-through cache for
5073 registers, only re-reading the registers if the target has run.
5075 There is also a new remote serial stub for SPARC processors. You can
5076 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5077 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5078 processor with a serial port.
5082 Configure.in files have become much easier to read and modify. A new
5083 `table driven' format makes it more obvious what configurations are
5084 supported, and what files each one uses.
5088 There is a new opcodes library which will eventually contain all of the
5089 disassembly routines and opcode tables. At present, it only contains
5090 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5091 disassembler (binutils/objdump) to share these routines.
5093 The libiberty library is now copylefted under the GNU Library General
5094 Public License. This allows more liberal use, and was done so libg++
5095 can use it. This makes no difference to GDB, since the Library License
5096 grants all the rights from the General Public License.
5100 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5101 reference to the stabs symbol info used by the debugger. It is (as far
5102 as we know) the only published document on this fascinating topic. We
5103 encourage you to read it, compare it to the stabs information on your
5104 system, and send improvements on the document in general (to
5105 bug-gdb@prep.ai.mit.edu).
5107 And, of course, many bugs have been fixed.
5110 *** Changes in GDB-4.6:
5112 * Better support for C++ function names
5114 GDB now accepts as input the "demangled form" of C++ overloaded function
5115 names and member function names, and can do command completion on such names
5116 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5117 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5118 Make use of command completion, it is your friend.
5120 GDB also now accepts a variety of C++ mangled symbol formats. They are
5121 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5122 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5123 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5124 for the list of formats.
5126 * G++ symbol mangling problem
5128 Recent versions of gcc have a bug in how they emit debugging information for
5129 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5130 directory) can be applied to gcc to fix the problem. Alternatively, if you
5131 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5132 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5133 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5136 * New 'maintenance' command
5138 All of the commands related to hacking GDB internals have been moved out of
5139 the main command set, and now live behind the 'maintenance' command. This
5140 can also be abbreviated as 'mt'. The following changes were made:
5142 dump-me -> maintenance dump-me
5143 info all-breakpoints -> maintenance info breakpoints
5144 printmsyms -> maintenance print msyms
5145 printobjfiles -> maintenance print objfiles
5146 printpsyms -> maintenance print psymbols
5147 printsyms -> maintenance print symbols
5149 The following commands are new:
5151 maintenance demangle Call internal GDB demangler routine to
5152 demangle a C++ link name and prints the result.
5153 maintenance print type Print a type chain for a given symbol
5155 * Change to .gdbinit file processing
5157 We now read the $HOME/.gdbinit file before processing the argv arguments
5158 (e.g. reading symbol files or core files). This allows global parameters to
5159 be set, which will apply during the symbol reading. The ./.gdbinit is still
5160 read after argv processing.
5162 * New hosts supported
5164 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5166 GNU/Linux support i386-unknown-linux or linux
5168 We are also including code to support the HP/PA running BSD and HPUX. This
5169 is almost guaranteed not to work, as we didn't have time to test or build it
5170 for this release. We are including it so that the more adventurous (or
5171 masochistic) of you can play with it. We also had major problems with the
5172 fact that the compiler that we got from HP doesn't support the -g option.
5175 * New targets supported
5177 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5179 * More smarts about finding #include files
5181 GDB now remembers the compilation directory for all include files, and for
5182 all files from which C is generated (like yacc and lex sources). This
5183 greatly improves GDB's ability to find yacc/lex sources, and include files,
5184 especially if you are debugging your program from a directory different from
5185 the one that contains your sources.
5187 We also fixed a bug which caused difficulty with listing and setting
5188 breakpoints in include files which contain C code. (In the past, you had to
5189 try twice in order to list an include file that you hadn't looked at before.)
5191 * Interesting infernals change
5193 GDB now deals with arbitrary numbers of sections, where the symbols for each
5194 section must be relocated relative to that section's landing place in the
5195 target's address space. This work was needed to support ELF with embedded
5196 stabs used by Solaris-2.0.
5198 * Bug fixes (of course!)
5200 There have been loads of fixes for the following things:
5201 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5202 i960, stabs, DOS(GO32), procfs, etc...
5204 See the ChangeLog for details.
5206 *** Changes in GDB-4.5:
5208 * New machines supported (host and target)
5210 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5212 SGI Irix-4.x mips-sgi-irix4 or iris4
5214 * New malloc package
5216 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5217 Mmalloc is capable of handling mutiple heaps of memory. It is also
5218 capable of saving a heap to a file, and then mapping it back in later.
5219 This can be used to greatly speedup the startup of GDB by using a
5220 pre-parsed symbol table which lives in a mmalloc managed heap. For
5221 more details, please read mmalloc/mmalloc.texi.
5225 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5226 'help info proc' for details.
5228 * MIPS ecoff symbol table format
5230 The code that reads MIPS symbol table format is now supported on all hosts.
5231 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5234 * File name changes for MS-DOS
5236 Many files in the config directories have been renamed to make it easier to
5237 support GDB on MS-DOSe systems (which have very restrictive file name
5238 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5239 environment) is close to working but has some remaining problems. Note
5240 that debugging of DOS programs is not supported, due to limitations
5241 in the ``operating system'', but it can be used to host cross-debugging.
5243 * Cross byte order fixes
5245 Many fixes have been made to support cross debugging of Sparc and MIPS
5246 targets from hosts whose byte order differs.
5248 * New -mapped and -readnow options
5250 If memory-mapped files are available on your system through the 'mmap'
5251 system call, you can use the -mapped option on the `file' or
5252 `symbol-file' commands to cause GDB to write the symbols from your
5253 program into a reusable file. If the program you are debugging is
5254 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5255 Future GDB debugging sessions will notice the presence of this file,
5256 and will quickly map in symbol information from it, rather than reading
5257 the symbol table from the executable program. Using the '-mapped'
5258 option in a GDB `file' or `symbol-file' command has the same effect as
5259 starting GDB with the '-mapped' command-line option.
5261 You can cause GDB to read the entire symbol table immediately by using
5262 the '-readnow' option with any of the commands that load symbol table
5263 information (or on the GDB command line). This makes the command
5264 slower, but makes future operations faster.
5266 The -mapped and -readnow options are typically combined in order to
5267 build a `fred.syms' file that contains complete symbol information.
5268 A simple GDB invocation to do nothing but build a `.syms' file for future
5271 gdb -batch -nx -mapped -readnow programname
5273 The `.syms' file is specific to the host machine on which GDB is run.
5274 It holds an exact image of GDB's internal symbol table. It cannot be
5275 shared across multiple host platforms.
5277 * longjmp() handling
5279 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5280 siglongjmp() without losing control. This feature has not yet been ported to
5281 all systems. It currently works on many 386 platforms, all MIPS-based
5282 platforms (SGI, DECstation, etc), and Sun3/4.
5286 Preliminary work has been put in to support the new Solaris OS from Sun. At
5287 this time, it can control and debug processes, but it is not capable of
5292 As always, many many bug fixes. The major areas were with g++, and mipsread.
5293 People using the MIPS-based platforms should experience fewer mysterious
5294 crashes and trashed symbol tables.
5296 *** Changes in GDB-4.4:
5298 * New machines supported (host and target)
5300 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5302 BSD Reno on Vax vax-dec-bsd
5303 Ultrix on Vax vax-dec-ultrix
5305 * New machines supported (target)
5307 AMD 29000 embedded, using EBMON a29k-none-none
5311 GDB continues to improve its handling of C++. `References' work better.
5312 The demangler has also been improved, and now deals with symbols mangled as
5313 per the Annotated C++ Reference Guide.
5315 GDB also now handles `stabs' symbol information embedded in MIPS
5316 `ecoff' symbol tables. Since the ecoff format was not easily
5317 extensible to handle new languages such as C++, this appeared to be a
5318 good way to put C++ debugging info into MIPS binaries. This option
5319 will be supported in the GNU C compiler, version 2, when it is
5322 * New features for SVR4
5324 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5325 shared libraries. Debugging dynamically linked programs should present
5326 only minor differences from debugging statically linked programs.
5328 The `info proc' command will print out information about any process
5329 on an SVR4 system (including the one you are debugging). At the moment,
5330 it prints the address mappings of the process.
5332 If you bring up GDB on another SVR4 system, please send mail to
5333 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5335 * Better dynamic linking support in SunOS
5337 Reading symbols from shared libraries which contain debugging symbols
5338 now works properly. However, there remain issues such as automatic
5339 skipping of `transfer vector' code during function calls, which
5340 make it harder to debug code in a shared library, than to debug the
5341 same code linked statically.
5345 GDB is now using the latest `getopt' routines from the FSF. This
5346 version accepts the -- prefix for options with long names. GDB will
5347 continue to accept the old forms (-option and +option) as well.
5348 Various single letter abbreviations for options have been explicity
5349 added to the option table so that they won't get overshadowed in the
5350 future by other options that begin with the same letter.
5354 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5355 Many assorted bugs have been handled. Many more remain to be handled.
5356 See the various ChangeLog files (primarily in gdb and bfd) for details.
5359 *** Changes in GDB-4.3:
5361 * New machines supported (host and target)
5363 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5364 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5365 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5367 * Almost SCO Unix support
5369 We had hoped to support:
5370 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5371 (except for core file support), but we discovered very late in the release
5372 that it has problems with process groups that render gdb unusable. Sorry
5373 about that. I encourage people to fix it and post the fixes.
5375 * Preliminary ELF and DWARF support
5377 GDB can read ELF object files on System V Release 4, and can handle
5378 debugging records for C, in DWARF format, in ELF files. This support
5379 is preliminary. If you bring up GDB on another SVR4 system, please
5380 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5385 GDB now uses the latest `readline' library. One user-visible change
5386 is that two tabs will list possible command completions, which previously
5387 required typing M-? (meta-question mark, or ESC ?).
5391 The `stepi' bug that many of you noticed has been squashed.
5392 Many bugs in C++ have been handled. Many more remain to be handled.
5393 See the various ChangeLog files (primarily in gdb and bfd) for details.
5395 * State of the MIPS world (in case you wondered):
5397 GDB can understand the symbol tables emitted by the compilers
5398 supplied by most vendors of MIPS-based machines, including DEC. These
5399 symbol tables are in a format that essentially nobody else uses.
5401 Some versions of gcc come with an assembler post-processor called
5402 mips-tfile. This program is required if you want to do source-level
5403 debugging of gcc-compiled programs. I believe FSF does not ship
5404 mips-tfile with gcc version 1, but it will eventually come with gcc
5407 Debugging of g++ output remains a problem. g++ version 1.xx does not
5408 really support it at all. (If you're lucky, you should be able to get
5409 line numbers and stack traces to work, but no parameters or local
5410 variables.) With some work it should be possible to improve the
5413 When gcc version 2 is released, you will have somewhat better luck.
5414 However, even then you will get confusing results for inheritance and
5417 We will eventually provide full debugging of g++ output on
5418 DECstations. This will probably involve some kind of stabs-in-ecoff
5419 encapulation, but the details have not been worked out yet.
5422 *** Changes in GDB-4.2:
5424 * Improved configuration
5426 Only one copy of `configure' exists now, and it is not self-modifying.
5427 Porting BFD is simpler.
5431 The `step' and `next' commands now only stop at the first instruction
5432 of a source line. This prevents the multiple stops that used to occur
5433 in switch statements, for-loops, etc. `Step' continues to stop if a
5434 function that has debugging information is called within the line.
5438 Lots of small bugs fixed. More remain.
5440 * New host supported (not target)
5442 Intel 386 PC clone running Mach i386-none-mach
5445 *** Changes in GDB-4.1:
5447 * Multiple source language support
5449 GDB now has internal scaffolding to handle several source languages.
5450 It determines the type of each source file from its filename extension,
5451 and will switch expression parsing and number formatting to match the
5452 language of the function in the currently selected stack frame.
5453 You can also specifically set the language to be used, with
5454 `set language c' or `set language modula-2'.
5458 GDB now has preliminary support for the GNU Modula-2 compiler,
5459 currently under development at the State University of New York at
5460 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5461 continue through the fall of 1991 and into 1992.
5463 Other Modula-2 compilers are currently not supported, and attempting to
5464 debug programs compiled with them will likely result in an error as the
5465 symbol table is read. Feel free to work on it, though!
5467 There are hooks in GDB for strict type checking and range checking,
5468 in the `Modula-2 philosophy', but they do not currently work.
5472 GDB can now write to executable and core files (e.g. patch
5473 a variable's value). You must turn this switch on, specify
5474 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5475 by assigning a new value to a variable. Modifications take
5478 * Automatic SunOS shared library reading
5480 When you run your program, GDB automatically determines where its
5481 shared libraries (if any) have been loaded, and reads their symbols.
5482 The `share' command is no longer needed. This also works when
5483 examining core files.
5487 You can specify the number of lines that the `list' command shows.
5490 * New machines supported (host and target)
5492 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5493 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5494 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5496 * New hosts supported (not targets)
5498 IBM RT/PC: romp-ibm-aix or rtpc
5500 * New targets supported (not hosts)
5502 AMD 29000 embedded with COFF a29k-none-coff
5503 AMD 29000 embedded with a.out a29k-none-aout
5504 Ultracomputer remote kernel debug a29k-nyu-kern
5506 * New remote interfaces
5512 *** Changes in GDB-4.0:
5516 Wide output is wrapped at good places to make the output more readable.
5518 Gdb now supports cross-debugging from a host machine of one type to a
5519 target machine of another type. Communication with the target system
5520 is over serial lines. The ``target'' command handles connecting to the
5521 remote system; the ``load'' command will download a program into the
5522 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5523 also supports debugging of realtime processes running under VxWorks,
5524 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5525 stub on the target system.
5527 New CPUs supported include the AMD 29000 and Intel 960.
5529 GDB now reads object files and symbol tables via a ``binary file''
5530 library, which allows a single copy of GDB to debug programs of multiple
5531 object file types such as a.out and coff.
5533 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5534 refcard.dvi and refcard.ps are available to format it).
5537 * Control-Variable user interface simplified
5539 All variables that control the operation of the debugger can be set
5540 by the ``set'' command, and displayed by the ``show'' command.
5542 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5543 ``Show prompt'' produces the response:
5544 Gdb's prompt is new-gdb=>.
5546 What follows are the NEW set commands. The command ``help set'' will
5547 print a complete list of old and new set commands. ``help set FOO''
5548 will give a longer description of the variable FOO. ``show'' will show
5549 all of the variable descriptions and their current settings.
5551 confirm on/off: Enables warning questions for operations that are
5552 hard to recover from, e.g. rerunning the program while
5553 it is already running. Default is ON.
5555 editing on/off: Enables EMACS style command line editing
5556 of input. Previous lines can be recalled with
5557 control-P, the current line can be edited with control-B,
5558 you can search for commands with control-R, etc.
5561 history filename NAME: NAME is where the gdb command history
5562 will be stored. The default is .gdb_history,
5563 or the value of the environment variable
5566 history size N: The size, in commands, of the command history. The
5567 default is 256, or the value of the environment variable
5570 history save on/off: If this value is set to ON, the history file will
5571 be saved after exiting gdb. If set to OFF, the
5572 file will not be saved. The default is OFF.
5574 history expansion on/off: If this value is set to ON, then csh-like
5575 history expansion will be performed on
5576 command line input. The default is OFF.
5578 radix N: Sets the default radix for input and output. It can be set
5579 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5580 in the current radix, so "set radix 10" is always a no-op.
5582 height N: This integer value is the number of lines on a page. Default
5583 is 24, the current `stty rows'' setting, or the ``li#''
5584 setting from the termcap entry matching the environment
5587 width N: This integer value is the number of characters on a line.
5588 Default is 80, the current `stty cols'' setting, or the ``co#''
5589 setting from the termcap entry matching the environment
5592 Note: ``set screensize'' is obsolete. Use ``set height'' and
5593 ``set width'' instead.
5595 print address on/off: Print memory addresses in various command displays,
5596 such as stack traces and structure values. Gdb looks
5597 more ``symbolic'' if you turn this off; it looks more
5598 ``machine level'' with it on. Default is ON.
5600 print array on/off: Prettyprint arrays. New convenient format! Default
5603 print demangle on/off: Print C++ symbols in "source" form if on,
5606 print asm-demangle on/off: Same, for assembler level printouts
5609 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5612 * Support for Epoch Environment.
5614 The epoch environment is a version of Emacs v18 with windowing. One
5615 new command, ``inspect'', is identical to ``print'', except that if you
5616 are running in the epoch environment, the value is printed in its own
5620 * Support for Shared Libraries
5622 GDB can now debug programs and core files that use SunOS shared libraries.
5623 Symbols from a shared library cannot be referenced
5624 before the shared library has been linked with the program (this
5625 happens after you type ``run'' and before the function main() is entered).
5626 At any time after this linking (including when examining core files
5627 from dynamically linked programs), gdb reads the symbols from each
5628 shared library when you type the ``sharedlibrary'' command.
5629 It can be abbreviated ``share''.
5631 sharedlibrary REGEXP: Load shared object library symbols for files
5632 matching a unix regular expression. No argument
5633 indicates to load symbols for all shared libraries.
5635 info sharedlibrary: Status of loaded shared libraries.
5640 A watchpoint stops execution of a program whenever the value of an
5641 expression changes. Checking for this slows down execution
5642 tremendously whenever you are in the scope of the expression, but is
5643 quite useful for catching tough ``bit-spreader'' or pointer misuse
5644 problems. Some machines such as the 386 have hardware for doing this
5645 more quickly, and future versions of gdb will use this hardware.
5647 watch EXP: Set a watchpoint (breakpoint) for an expression.
5649 info watchpoints: Information about your watchpoints.
5651 delete N: Deletes watchpoint number N (same as breakpoints).
5652 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5653 enable N: Re-enables watchpoint number N (same as breakpoints).
5656 * C++ multiple inheritance
5658 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5661 * C++ exception handling
5663 Gdb now supports limited C++ exception handling. Besides the existing
5664 ability to breakpoint on an exception handler, gdb can breakpoint on
5665 the raising of an exception (before the stack is peeled back to the
5668 catch FOO: If there is a FOO exception handler in the dynamic scope,
5669 set a breakpoint to catch exceptions which may be raised there.
5670 Multiple exceptions (``catch foo bar baz'') may be caught.
5672 info catch: Lists all exceptions which may be caught in the
5673 current stack frame.
5676 * Minor command changes
5678 The command ``call func (arg, arg, ...)'' now acts like the print
5679 command, except it does not print or save a value if the function's result
5680 is void. This is similar to dbx usage.
5682 The ``up'' and ``down'' commands now always print the frame they end up
5683 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5684 frames without printing.
5686 * New directory command
5688 'dir' now adds directories to the FRONT of the source search path.
5689 The path starts off empty. Source files that contain debug information
5690 about the directory in which they were compiled can be found even
5691 with an empty path; Sun CC and GCC include this information. If GDB can't
5692 find your source file in the current directory, type "dir .".
5694 * Configuring GDB for compilation
5696 For normal use, type ``./configure host''. See README or gdb.texinfo
5699 GDB now handles cross debugging. If you are remotely debugging between
5700 two different machines, type ``./configure host -target=targ''.
5701 Host is the machine where GDB will run; targ is the machine
5702 where the program that you are debugging will run.
5704 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5706 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5708 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5709 $k0 - $k7 on GNU/Linux.