1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
8 * Improved support for process record-replay and reverse debugging on
9 arm*-linux* targets. Support for thumb32 and syscall instruction
10 recording has been added.
12 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
14 * GDB now supports Fission DWP file format version 2.
15 http://gcc.gnu.org/wiki/DebugFission
17 * New convenience function "$_isvoid", to check whether an expression
18 is void. A void expression is an expression where the type of the
19 result is "void". For example, some convenience variables may be
20 "void" when evaluated (e.g., "$_exitcode" before the execution of
21 the program being debugged; or an undefined convenience variable).
22 Another example, when calling a function whose return type is
25 * The "maintenance print objfiles" command now takes an optional regexp.
27 * The "catch syscall" command now works on arm*-linux* targets.
29 * GDB now consistently shows "<not saved>" when printing values of
30 registers the debug info indicates have not been saved in the frame
31 and there's nowhere to retrieve them from
32 (callee-saved/call-clobbered registers):
37 (gdb) info registers rax
40 Before, the former would print "<optimized out>", and the latter
41 "*value not available*".
43 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
48 ** Frame filters and frame decorators have been added.
49 ** Temporary breakpoints are now supported.
50 ** Line tables representation has been added.
51 ** New attribute 'parent_type' for gdb.Field objects.
52 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
53 ** New attribute 'name' for gdb.Type objects.
57 Nios II ELF nios2*-*-elf
58 Nios II GNU/Linux nios2*-*-linux
59 Texas Instruments MSP430 msp430*-*-elf
61 * Removed native configurations
63 Support for these a.out NetBSD and OpenBSD obsolete configurations has
64 been removed. ELF variants of these configurations are kept supported.
66 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
67 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
68 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
69 i[34567]86-*-openbsd3.[0-3]
70 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
71 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
72 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
76 Like "catch throw", but catches a re-thrown exception.
78 Renamed from old "maint check-symtabs".
80 Perform consistency checks on symtabs.
82 Expand symtabs matching an optional regexp.
85 Display the details of GDB configure-time options.
87 maint set|show per-command
88 maint set|show per-command space
89 maint set|show per-command time
90 maint set|show per-command symtab
91 Enable display of per-command gdb resource usage.
93 remove-symbol-file FILENAME
94 remove-symbol-file -a ADDRESS
95 Remove a symbol file added via add-symbol-file. The file to remove
96 can be identified by its filename or by an address that lies within
97 the boundaries of this symbol file in memory.
100 info exceptions REGEXP
101 Display the list of Ada exceptions defined in the program being
102 debugged. If provided, only the exceptions whose names match REGEXP
107 set debug symfile off|on
109 Control display of debugging info regarding reading symbol files and
110 symbol tables within those files
112 set print raw frame-arguments
113 show print raw frame-arguments
114 Set/show whether to print frame arguments in raw mode,
115 disregarding any defined pretty-printers.
117 set remote trace-status-packet
118 show remote trace-status-packet
119 Set/show the use of remote protocol qTStatus packet.
123 Control display of debugging messages related to Nios II targets.
127 Control whether target-assisted range stepping is enabled.
129 set startup-with-shell
130 show startup-with-shell
131 Specifies whether Unix child processes are started via a shell or
136 Use the target memory cache for accesses to the code segment. This
137 improves performance of remote debugging (particularly disassembly).
139 * You can now use a literal value 'unlimited' for options that
140 interpret 0 or -1 as meaning "unlimited". E.g., "set
141 trace-buffer-size unlimited" is now an alias for "set
142 trace-buffer-size -1" and "set height unlimited" is now an alias for
145 * The "set debug symtab-create" debugging option of GDB has been changed to
146 accept a verbosity level. 0 means "off", 1 provides basic debugging
147 output, and values of 2 or greater provides more verbose output.
149 * New command-line options
151 Display the details of GDB configure-time options.
153 * The command 'tsave' can now support new option '-ctf' to save trace
154 buffer in Common Trace Format.
156 * Newly installed $prefix/bin/gcore acts as a shell interface for the
159 * GDB now implements the the C++ 'typeid' operator.
161 * The new convenience variable $_exception holds the exception being
162 thrown or caught at an exception-related catchpoint.
164 * The exception-related catchpoints, like "catch throw", now accept a
165 regular expression which can be used to filter exceptions by type.
167 * The new convenience variable $_exitsignal is automatically set to
168 the terminating signal number when the program being debugged dies
169 due to an uncaught signal.
173 ** All MI commands now accept an optional "--language" option.
174 Support for this feature can be verified by using the "-list-features"
175 command, which should contain "language-option".
177 ** The new command -info-gdb-mi-command allows the user to determine
178 whether a GDB/MI command is supported or not.
180 ** The "^error" result record returned when trying to execute an undefined
181 GDB/MI command now provides a variable named "code" whose content is the
182 "undefined-command" error code. Support for this feature can be verified
183 by using the "-list-features" command, which should contain
184 "undefined-command-error-code".
186 ** The -trace-save MI command can optionally save trace buffer in Common
189 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
191 ** The command -data-list-register-values now accepts an optional
192 "--skip-unavailable" option. When used, only the available registers
195 ** The new command -trace-frame-collected dumps collected variables,
196 computed expressions, tvars, memory and registers in a traceframe.
198 ** The commands -stack-list-locals, -stack-list-arguments and
199 -stack-list-variables now accept an option "--skip-unavailable".
200 When used, only the available locals or arguments are displayed.
202 ** The -exec-run command now accepts an optional "--start" option.
203 When used, the command follows the same semantics as the "start"
204 command, stopping the program's execution at the start of its
205 main subprogram. Support for this feature can be verified using
206 the "-list-features" command, which should contain
207 "exec-run-start-option".
209 ** The new commands -catch-assert and -catch-exceptions insert
210 catchpoints stopping the program when Ada exceptions are raised.
212 ** The new command -info-ada-exceptions provides the equivalent of
213 the new "info exceptions" command.
215 * New system-wide configuration scripts
216 A GDB installation now provides scripts suitable for use as system-wide
217 configuration scripts for the following systems:
221 * GDB now supports target-assigned range stepping with remote targets.
222 This improves the performance of stepping source lines by reducing
223 the number of control packets from/to GDB. See "New remote packets"
226 * GDB now understands the element 'tvar' in the XML traceframe info.
227 It has the id of the collected trace state variables.
229 * On S/390 targets that provide the transactional-execution feature,
230 the program interruption transaction diagnostic block (TDB) is now
231 represented as a number of additional "registers" in GDB.
237 The vCont packet supports a new 'r' action, that tells the remote
238 stub to step through an address range itself, without GDB
239 involvemement at each single-step.
241 qXfer:libraries-svr4:read's annex
242 The previously unused annex of the qXfer:libraries-svr4:read packet
243 is now used to support passing an argument list. The remote stub
244 reports support for this argument list to GDB's qSupported query.
245 The defined arguments are "start" and "prev", used to reduce work
246 necessary for library list updating, resulting in significant
249 * New features in the GDB remote stub, GDBserver
251 ** GDBserver now supports target-assisted range stepping. Currently
252 enabled on x86/x86_64 GNU/Linux targets.
254 ** GDBserver now adds element 'tvar' in the XML in the reply to
255 'qXfer:traceframe-info:read'. It has the id of the collected
256 trace state variables.
258 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
261 * New 'z' formatter for printing and examining memory, this displays the
262 value as hexadecimal zero padded on the left to the size of the type.
264 * GDB can now use Windows x64 unwinding data.
266 * The "set remotebaud" command has been replaced by "set serial baud".
267 Similarly, "show remotebaud" has been replaced by "show serial baud".
268 The "set remotebaud" and "show remotebaud" commands are still available
269 to provide backward compatibility with older versions of GDB.
271 *** Changes in GDB 7.6
273 * Target record has been renamed to record-full.
274 Record/replay is now enabled with the "record full" command.
275 This also affects settings that are associated with full record/replay
276 that have been moved from "set/show record" to "set/show record full":
278 set|show record full insn-number-max
279 set|show record full stop-at-limit
280 set|show record full memory-query
282 * A new record target "record-btrace" has been added. The new target
283 uses hardware support to record the control-flow of a process. It
284 does not support replaying the execution, but it implements the
285 below new commands for investigating the recorded execution log.
286 This new recording method can be enabled using:
290 The "record-btrace" target is only available on Intel Atom processors
291 and requires a Linux kernel 2.6.32 or later.
293 * Two new commands have been added for record/replay to give information
294 about the recorded execution without having to replay the execution.
295 The commands are only supported by "record btrace".
297 record instruction-history prints the execution history at
298 instruction granularity
300 record function-call-history prints the execution history at
303 * New native configurations
305 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
306 FreeBSD/powerpc powerpc*-*-freebsd
307 x86_64/Cygwin x86_64-*-cygwin*
308 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
312 ARM AArch64 aarch64*-*-elf
313 ARM AArch64 GNU/Linux aarch64*-*-linux
314 Lynx 178 PowerPC powerpc-*-lynx*178
315 x86_64/Cygwin x86_64-*-cygwin*
316 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
318 * If the configured location of system.gdbinit file (as given by the
319 --with-system-gdbinit option at configure time) is in the
320 data-directory (as specified by --with-gdb-datadir at configure
321 time) or in one of its subdirectories, then GDB will look for the
322 system-wide init file in the directory specified by the
323 --data-directory command-line option.
325 * New command line options:
327 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
328 other initialization files, unlike -nx which disables all of them.
330 * Removed command line options
332 -epoch This was used by the gdb mode in Epoch, an ancient fork of
335 * The 'ptype' and 'whatis' commands now accept an argument to control
338 * 'info proc' now works on some core files.
342 ** Vectors can be created with gdb.Type.vector.
344 ** Python's atexit.register now works in GDB.
346 ** Types can be pretty-printed via a Python API.
348 ** Python 3 is now supported (in addition to Python 2.4 or later)
350 ** New class gdb.Architecture exposes GDB's internal representation
351 of architecture in the Python API.
353 ** New method Frame.architecture returns the gdb.Architecture object
354 corresponding to the frame's architecture.
356 * New Python-based convenience functions:
358 ** $_memeq(buf1, buf2, length)
359 ** $_streq(str1, str2)
361 ** $_regex(str, regex)
363 * The 'cd' command now defaults to using '~' (the home directory) if not
366 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
367 default for GCC since November 2000.
369 * The command 'forward-search' can now be abbreviated as 'fo'.
371 * The command 'info tracepoints' can now display 'installed on target'
372 or 'not installed on target' for each non-pending location of tracepoint.
374 * New configure options
376 --enable-libmcheck/--disable-libmcheck
377 By default, development versions are built with -lmcheck on hosts
378 that support it, in order to help track memory corruption issues.
379 Release versions, on the other hand, are built without -lmcheck
380 by default. The --enable-libmcheck/--disable-libmcheck configure
381 options allow the user to override that default.
382 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
383 This configure option allows the user to build GDB with
384 libbabeltrace using which GDB can read Common Trace Format data.
386 * New commands (for set/show, see "New options" below)
389 Catch signals. This is similar to "handle", but allows commands and
390 conditions to be attached.
393 List the BFDs known to GDB.
395 python-interactive [command]
397 Start a Python interactive prompt, or evaluate the optional command
398 and print the result of expressions.
401 "py" is a new alias for "python".
403 enable type-printer [name]...
404 disable type-printer [name]...
405 Enable or disable type printers.
409 ** For the Renesas Super-H architecture, the "regs" command has been removed
410 (has been deprecated in GDB 7.5), and "info all-registers" should be used
415 set print type methods (on|off)
416 show print type methods
417 Control whether method declarations are displayed by "ptype".
418 The default is to show them.
420 set print type typedefs (on|off)
421 show print type typedefs
422 Control whether typedef definitions are displayed by "ptype".
423 The default is to show them.
425 set filename-display basename|relative|absolute
426 show filename-display
427 Control the way in which filenames is displayed.
428 The default is "relative", which preserves previous behavior.
430 set trace-buffer-size
431 show trace-buffer-size
432 Request target to change the size of trace buffer.
434 set remote trace-buffer-size-packet auto|on|off
435 show remote trace-buffer-size-packet
436 Control the use of the remote protocol `QTBuffer:size' packet.
440 Control display of debugging messages related to ARM AArch64.
443 set debug coff-pe-read
444 show debug coff-pe-read
445 Control display of debugging messages related to reading of COFF/PE
450 Control display of debugging messages related to Mach-O symbols
453 set debug notification
454 show debug notification
455 Control display of debugging info for async remote notification.
459 ** Command parameter changes are now notified using new async record
460 "=cmd-param-changed".
461 ** Trace frame changes caused by command "tfind" are now notified using
462 new async record "=traceframe-changed".
463 ** The creation, deletion and modification of trace state variables
464 are now notified using new async records "=tsv-created",
465 "=tsv-deleted" and "=tsv-modified".
466 ** The start and stop of process record are now notified using new
467 async record "=record-started" and "=record-stopped".
468 ** Memory changes are now notified using new async record
470 ** The data-disassemble command response will include a "fullname" field
471 containing the absolute file name when source has been requested.
472 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
473 command, to allow pattern filling of memory areas.
474 ** New commands "-catch-load"/"-catch-unload" added for intercepting
475 library load/unload events.
476 ** The response to breakpoint commands and breakpoint async records
477 includes an "installed" field containing a boolean state about each
478 non-pending tracepoint location is whether installed on target or not.
479 ** Output of the "-trace-status" command includes a "trace-file" field
480 containing the name of the trace file being examined. This field is
481 optional, and only present when examining a trace file.
482 ** The "fullname" field is now always present along with the "file" field,
483 even if the file cannot be found by GDB.
485 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
486 You must have the LZMA library available when configuring GDB for this
487 feature to be enabled. For more information, see:
488 http://fedoraproject.org/wiki/Features/MiniDebugInfo
493 Set the size of trace buffer. The remote stub reports support for this
494 packet to gdb's qSupported query.
497 Enable Branch Trace Store (BTS)-based branch tracing for the current
498 thread. The remote stub reports support for this packet to gdb's
502 Disable branch tracing for the current thread. The remote stub reports
503 support for this packet to gdb's qSupported query.
506 Read the traced branches for the current thread. The remote stub
507 reports support for this packet to gdb's qSupported query.
509 *** Changes in GDB 7.5
511 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
512 for more x32 ABI info.
514 * GDB now supports access to MIPS DSP registers on Linux targets.
516 * GDB now supports debugging microMIPS binaries.
518 * The "info os" command on GNU/Linux can now display information on
519 several new classes of objects managed by the operating system:
520 "info os procgroups" lists process groups
521 "info os files" lists file descriptors
522 "info os sockets" lists internet-domain sockets
523 "info os shm" lists shared-memory regions
524 "info os semaphores" lists semaphores
525 "info os msg" lists message queues
526 "info os modules" lists loaded kernel modules
528 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
529 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
530 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
531 options and inspect the probe arguments using the new $_probe_arg family
532 of convenience variables. You can obtain more information about SystemTap
533 in <http://sourceware.org/systemtap/>.
535 * GDB now supports reversible debugging on ARM, it allows you to
536 debug basic ARM and THUMB instructions, and provides
537 record/replay support.
539 * The option "symbol-reloading" has been deleted as it is no longer used.
543 ** GDB commands implemented in Python can now be put in command class
546 ** The "maint set python print-stack on|off" is now deleted.
548 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
549 apply "flag enum"-style pretty-printing to any enum.
551 ** gdb.lookup_symbol can now work when there is no current frame.
553 ** gdb.Symbol now has a 'line' attribute, holding the line number in
554 the source at which the symbol was defined.
556 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
557 method 'value'. The former indicates whether the symbol needs a
558 frame in order to compute its value, and the latter computes the
561 ** A new method 'referenced_value' on gdb.Value objects which can
562 dereference pointer as well as C++ reference values.
564 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
565 which return the global and static blocks (as gdb.Block objects),
566 of the underlying symbol table, respectively.
568 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
569 object associated with a PC value.
571 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
572 of the address range occupied by code for the current source line.
574 * Go language support.
575 GDB now supports debugging programs written in the Go programming
578 * GDBserver now supports stdio connections.
579 E.g. (gdb) target remote | ssh myhost gdbserver - hello
581 * The binary "gdbtui" can no longer be built or installed.
582 Use "gdb -tui" instead.
584 * GDB will now print "flag" enums specially. A flag enum is one where
585 all the enumerator values have no bits in common when pairwise
586 "and"ed. When printing a value whose type is a flag enum, GDB will
587 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
588 (gdb) print (enum E) 3
591 * The filename part of a linespec will now match trailing components
592 of a source file name. For example, "break gcc/expr.c:1000" will
593 now set a breakpoint in build/gcc/expr.c, but not
596 * The "info proc" and "generate-core-file" commands will now also
597 work on remote targets connected to GDBserver on Linux.
599 * The command "info catch" has been removed. It has been disabled
602 * The "catch exception" and "catch assert" commands now accept
603 a condition at the end of the command, much like the "break"
604 command does. For instance:
606 (gdb) catch exception Constraint_Error if Barrier = True
608 Previously, it was possible to add a condition to such catchpoints,
609 but it had to be done as a second step, after the catchpoint had been
610 created, using the "condition" command.
612 * The "info static-tracepoint-marker" command will now also work on
613 native Linux targets with in-process agent.
615 * GDB can now set breakpoints on inlined functions.
617 * The .gdb_index section has been updated to include symbols for
618 inlined functions. GDB will ignore older .gdb_index sections by
619 default, which could cause symbol files to be loaded more slowly
620 until their .gdb_index sections can be recreated. The new command
621 "set use-deprecated-index-sections on" will cause GDB to use any older
622 .gdb_index sections it finds. This will restore performance, but the
623 ability to set breakpoints on inlined functions will be lost in symbol
624 files with older .gdb_index sections.
626 The .gdb_index section has also been updated to record more information
627 about each symbol. This speeds up the "info variables", "info functions"
628 and "info types" commands when used with programs having the .gdb_index
629 section, as well as speeding up debugging with shared libraries using
630 the .gdb_index section.
632 * Ada support for GDB/MI Variable Objects has been added.
634 * GDB can now support 'breakpoint always-inserted mode' in 'record'
639 ** New command -info-os is the MI equivalent of "info os".
641 ** Output logs ("set logging" and related) now include MI output.
645 ** "set use-deprecated-index-sections on|off"
646 "show use-deprecated-index-sections on|off"
647 Controls the use of deprecated .gdb_index sections.
649 ** "catch load" and "catch unload" can be used to stop when a shared
650 library is loaded or unloaded, respectively.
652 ** "enable count" can be used to auto-disable a breakpoint after
655 ** "info vtbl" can be used to show the virtual method tables for
656 C++ and Java objects.
658 ** "explore" and its sub commands "explore value" and "explore type"
659 can be used to recursively explore values and types of
660 expressions. These commands are available only if GDB is
661 configured with '--with-python'.
663 ** "info auto-load" shows status of all kinds of auto-loaded files,
664 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
665 sequences of commands files, "info auto-load python-scripts"
666 shows status of auto-loading Python script files,
667 "info auto-load local-gdbinit" shows status of loading init file
668 (.gdbinit) from current directory and "info auto-load libthread-db" shows
669 status of inferior specific thread debugging shared library loading.
671 ** "info auto-load-scripts", "set auto-load-scripts on|off"
672 and "show auto-load-scripts" commands have been deprecated, use their
673 "info auto-load python-scripts", "set auto-load python-scripts on|off"
674 and "show auto-load python-scripts" counterparts instead.
676 ** "dprintf location,format,args..." creates a dynamic printf, which
677 is basically a breakpoint that does a printf and immediately
678 resumes your program's execution, so it is like a printf that you
679 can insert dynamically at runtime instead of at compiletime.
681 ** "set print symbol"
683 Controls whether GDB attempts to display the symbol, if any,
684 corresponding to addresses it prints. This defaults to "on", but
685 you can set it to "off" to restore GDB's previous behavior.
687 * Deprecated commands
689 ** For the Renesas Super-H architecture, the "regs" command has been
690 deprecated, and "info all-registers" should be used instead.
694 Renesas RL78 rl78-*-elf
695 HP OpenVMS ia64 ia64-hp-openvms*
697 * GDBserver supports evaluation of breakpoint conditions. When
698 support is advertised by GDBserver, GDB may be told to send the
699 breakpoint conditions in bytecode form to GDBserver. GDBserver
700 will only report the breakpoint trigger to GDB when its condition
706 show mips compression
707 Select the compressed ISA encoding used in functions that have no symbol
708 information available. The encoding can be set to either of:
711 and is updated automatically from ELF file flags if available.
713 set breakpoint condition-evaluation
714 show breakpoint condition-evaluation
715 Control whether breakpoint conditions are evaluated by GDB ("host") or by
716 GDBserver ("target"). Default option "auto" chooses the most efficient
718 This option can improve debugger efficiency depending on the speed of the
722 Disable auto-loading globally.
725 Show auto-loading setting of all kinds of auto-loaded files.
727 set auto-load gdb-scripts on|off
728 show auto-load gdb-scripts
729 Control auto-loading of GDB canned sequences of commands files.
731 set auto-load python-scripts on|off
732 show auto-load python-scripts
733 Control auto-loading of Python script files.
735 set auto-load local-gdbinit on|off
736 show auto-load local-gdbinit
737 Control loading of init file (.gdbinit) from current directory.
739 set auto-load libthread-db on|off
740 show auto-load libthread-db
741 Control auto-loading of inferior specific thread debugging shared library.
743 set auto-load scripts-directory <dir1>[:<dir2>...]
744 show auto-load scripts-directory
745 Set a list of directories from which to load auto-loaded scripts.
746 Automatically loaded Python scripts and GDB scripts are located in one
747 of the directories listed by this option.
748 The delimiter (':' above) may differ according to the host platform.
750 set auto-load safe-path <dir1>[:<dir2>...]
751 show auto-load safe-path
752 Set a list of directories from which it is safe to auto-load files.
753 The delimiter (':' above) may differ according to the host platform.
755 set debug auto-load on|off
757 Control display of debugging info for auto-loading the files above.
759 set dprintf-style gdb|call|agent
761 Control the way in which a dynamic printf is performed; "gdb"
762 requests a GDB printf command, while "call" causes dprintf to call a
763 function in the inferior. "agent" requests that the target agent
764 (such as GDBserver) do the printing.
766 set dprintf-function <expr>
767 show dprintf-function
768 set dprintf-channel <expr>
770 Set the function and optional first argument to the call when using
771 the "call" style of dynamic printf.
773 set disconnected-dprintf on|off
774 show disconnected-dprintf
775 Control whether agent-style dynamic printfs continue to be in effect
776 after GDB disconnects.
778 * New configure options
781 Configure default value for the 'set auto-load scripts-directory'
782 setting above. It defaults to '$debugdir:$datadir/auto-load',
783 $debugdir representing global debugging info directories (available
784 via 'show debug-file-directory') and $datadir representing GDB's data
785 directory (available via 'show data-directory').
787 --with-auto-load-safe-path
788 Configure default value for the 'set auto-load safe-path' setting
789 above. It defaults to the --with-auto-load-dir setting.
791 --without-auto-load-safe-path
792 Set 'set auto-load safe-path' to '/', effectively disabling this
797 z0/z1 conditional breakpoints extension
799 The z0/z1 breakpoint insertion packets have been extended to carry
800 a list of conditional expressions over to the remote stub depending on the
801 condition evaluation mode. The use of this extension can be controlled
802 via the "set remote conditional-breakpoints-packet" command.
806 Specify the signals which the remote stub may pass to the debugged
807 program without GDB involvement.
809 * New command line options
811 --init-command=FILE, -ix Like --command, -x but execute it
812 before loading inferior.
813 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
814 execute it before loading inferior.
816 *** Changes in GDB 7.4
818 * GDB now handles ambiguous linespecs more consistently; the existing
819 FILE:LINE support has been expanded to other types of linespecs. A
820 breakpoint will now be set on all matching locations in all
821 inferiors, and locations will be added or removed according to
824 * GDB now allows you to skip uninteresting functions and files when
825 stepping with the "skip function" and "skip file" commands.
827 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
828 and "show remote hardware-watchpoint-length-limit". These allows to
829 set or show the maximum length limit (in bytes) of a remote
830 target hardware watchpoint.
832 This allows e.g. to use "unlimited" hardware watchpoints with the
833 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
834 watchpoints are slower than real hardware watchpoints but are
835 significantly faster than gdb software watchpoints.
839 ** The register_pretty_printer function in module gdb.printing now takes
840 an optional `replace' argument. If True, the new printer replaces any
843 ** The "maint set python print-stack on|off" command has been
844 deprecated and will be deleted in GDB 7.5.
845 A new command: "set python print-stack none|full|message" has
846 replaced it. Additionally, the default for "print-stack" is
847 now "message", which just prints the error message without
850 ** A prompt substitution hook (prompt_hook) is now available to the
853 ** A new Python module, gdb.prompt has been added to the GDB Python
854 modules library. This module provides functionality for
855 escape sequences in prompts (used by set/show
856 extended-prompt). These escape sequences are replaced by their
859 ** Python commands and convenience-functions located in
860 'data-directory'/python/gdb/command and
861 'data-directory'/python/gdb/function are now automatically loaded
864 ** Blocks now provide four new attributes. global_block and
865 static_block will return the global and static blocks
866 respectively. is_static and is_global are boolean attributes
867 that indicate if the block is one of those two types.
869 ** Symbols now provide the "type" attribute, the type of the symbol.
871 ** The "gdb.breakpoint" function has been deprecated in favor of
874 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
875 of a function. This class is based on the "finish" command
876 available in the CLI.
878 ** Type objects for struct and union types now allow access to
879 the fields using standard Python dictionary (mapping) methods.
880 For example, "some_type['myfield']" now works, as does
883 ** A new event "gdb.new_objfile" has been added, triggered by loading a
886 ** A new function, "deep_items" has been added to the gdb.types
887 module in the GDB Python modules library. This function returns
888 an iterator over the fields of a struct or union type. Unlike
889 the standard Python "iteritems" method, it will recursively traverse
890 any anonymous fields.
894 ** "*stopped" events can report several new "reason"s, such as
897 ** Breakpoint changes are now notified using new async records, like
898 "=breakpoint-modified".
900 ** New command -ada-task-info.
902 * libthread-db-search-path now supports two special values: $sdir and $pdir.
903 $sdir specifies the default system locations of shared libraries.
904 $pdir specifies the directory where the libpthread used by the application
907 GDB no longer looks in $sdir and $pdir after it has searched the directories
908 mentioned in libthread-db-search-path. If you want to search those
909 directories, they must be specified in libthread-db-search-path.
910 The default value of libthread-db-search-path on GNU/Linux and Solaris
911 systems is now "$sdir:$pdir".
913 $pdir is not supported by gdbserver, it is currently ignored.
914 $sdir is supported by gdbserver.
916 * New configure option --with-iconv-bin.
917 When using the internationalization support like the one in the GNU C
918 library, GDB will invoke the "iconv" program to get a list of supported
919 character sets. If this program lives in a non-standard location, one can
920 use this option to specify where to find it.
922 * When natively debugging programs on PowerPC BookE processors running
923 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
924 watchpoints, which specify a mask in addition to an address to watch.
925 The mask specifies that some bits of an address (the bits which are
926 reset in the mask) should be ignored when matching the address accessed
927 by the inferior against the watchpoint address. See the "PowerPC Embedded"
928 section in the user manual for more details.
930 * The new option --once causes GDBserver to stop listening for connections once
931 the first connection is made. The listening port used by GDBserver will
932 become available after that.
934 * New commands "info macros" and "alias" have been added.
936 * New function parameters suffix @entry specifies value of function parameter
937 at the time the function got called. Entry values are available only since
943 "!" is now an alias of the "shell" command.
944 Note that no space is needed between "!" and SHELL COMMAND.
948 watch EXPRESSION mask MASK_VALUE
949 The watch command now supports the mask argument which allows creation
950 of masked watchpoints, if the current architecture supports this feature.
952 info auto-load-scripts [REGEXP]
953 This command was formerly named "maintenance print section-scripts".
954 It is now generally useful and is no longer a maintenance-only command.
956 info macro [-all] [--] MACRO
957 The info macro command has new options `-all' and `--'. The first for
958 printing all definitions of a macro. The second for explicitly specifying
959 the end of arguments and the beginning of the macro name in case the macro
960 name starts with a hyphen.
962 collect[/s] EXPRESSIONS
963 The tracepoint collect command now takes an optional modifier "/s"
964 that directs it to dereference pointer-to-character types and
965 collect the bytes of memory up to a zero byte. The behavior is
966 similar to what you see when you use the regular print command on a
967 string. An optional integer following the "/s" sets a bound on the
968 number of bytes that will be collected.
971 The trace start command now interprets any supplied arguments as a
972 note to be recorded with the trace run, with an effect similar to
973 setting the variable trace-notes.
976 The trace stop command now interprets any arguments as a note to be
977 mentioned along with the tstatus report that the trace was stopped
978 with a command. The effect is similar to setting the variable
981 * Tracepoints can now be enabled and disabled at any time after a trace
982 experiment has been started using the standard "enable" and "disable"
983 commands. It is now possible to start a trace experiment with no enabled
984 tracepoints; GDB will display a warning, but will allow the experiment to
985 begin, assuming that tracepoints will be enabled as needed while the trace
988 * Fast tracepoints on 32-bit x86-architectures can now be placed at
989 locations with 4-byte instructions, when they were previously
990 limited to locations with instructions of 5 bytes or longer.
994 set debug dwarf2-read
995 show debug dwarf2-read
996 Turns on or off display of debugging messages related to reading
997 DWARF debug info. The default is off.
999 set debug symtab-create
1000 show debug symtab-create
1001 Turns on or off display of debugging messages related to symbol table
1002 creation. The default is off.
1005 show extended-prompt
1006 Set the GDB prompt, and allow escape sequences to be inserted to
1007 display miscellaneous information (see 'help set extended-prompt'
1008 for the list of sequences). This prompt (and any information
1009 accessed through the escape sequences) is updated every time the
1010 prompt is displayed.
1012 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1013 show print entry-values
1014 Set printing of frame argument values at function entry. In some cases
1015 GDB can determine the value of function argument which was passed by the
1016 function caller, even if the value was modified inside the called function.
1018 set debug entry-values
1019 show debug entry-values
1020 Control display of debugging info for determining frame argument values at
1021 function entry and virtual tail call frames.
1023 set basenames-may-differ
1024 show basenames-may-differ
1025 Set whether a source file may have multiple base names.
1026 (A "base name" is the name of a file with the directory part removed.
1027 Example: The base name of "/home/user/hello.c" is "hello.c".)
1028 If set, GDB will canonicalize file names (e.g., expand symlinks)
1029 before comparing them. Canonicalization is an expensive operation,
1030 but it allows the same file be known by more than one base name.
1031 If not set (the default), all source files are assumed to have just
1032 one base name, and gdb will do file name comparisons more efficiently.
1038 Set a user name and notes for the current and any future trace runs.
1039 This is useful for long-running and/or disconnected traces, to
1040 inform others (or yourself) as to who is running the trace, supply
1041 contact information, or otherwise explain what is going on.
1043 set trace-stop-notes
1044 show trace-stop-notes
1045 Set a note attached to the trace run, that is displayed when the
1046 trace has been stopped by a tstop command. This is useful for
1047 instance as an explanation, if you are stopping a trace run that was
1048 started by someone else.
1050 * New remote packets
1054 Dynamically enable a tracepoint in a started trace experiment.
1058 Dynamically disable a tracepoint in a started trace experiment.
1062 Set the user and notes of the trace run.
1066 Query the current status of a tracepoint.
1070 Query the minimum length of instruction at which a fast tracepoint may
1073 * Dcache size (number of lines) and line-size are now runtime-configurable
1074 via "set dcache line" and "set dcache line-size" commands.
1078 Texas Instruments TMS320C6x tic6x-*-*
1082 Renesas RL78 rl78-*-elf
1084 *** Changes in GDB 7.3.1
1086 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1088 *** Changes in GDB 7.3
1090 * GDB has a new command: "thread find [REGEXP]".
1091 It finds the thread id whose name, target id, or thread extra info
1092 matches the given regular expression.
1094 * The "catch syscall" command now works on mips*-linux* targets.
1096 * The -data-disassemble MI command now supports modes 2 and 3 for
1097 dumping the instruction opcodes.
1099 * New command line options
1101 -data-directory DIR Specify DIR as the "data-directory".
1102 This is mostly for testing purposes.
1104 * The "maint set python auto-load on|off" command has been renamed to
1105 "set auto-load-scripts on|off".
1107 * GDB has a new command: "set directories".
1108 It is like the "dir" command except that it replaces the
1109 source path list instead of augmenting it.
1111 * GDB now understands thread names.
1113 On GNU/Linux, "info threads" will display the thread name as set by
1114 prctl or pthread_setname_np.
1116 There is also a new command, "thread name", which can be used to
1117 assign a name internally for GDB to display.
1120 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1121 has been integrated into GDB.
1125 ** The function gdb.Write now accepts an optional keyword 'stream'.
1126 This keyword, when provided, will direct the output to either
1127 stdout, stderr, or GDB's logging output.
1129 ** Parameters can now be be sub-classed in Python, and in particular
1130 you may implement the get_set_doc and get_show_doc functions.
1131 This improves how Parameter set/show documentation is processed
1132 and allows for more dynamic content.
1134 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1135 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1136 have an is_valid method.
1138 ** Breakpoints can now be sub-classed in Python, and in particular
1139 you may implement a 'stop' function that is executed each time
1140 the inferior reaches that breakpoint.
1142 ** New function gdb.lookup_global_symbol looks up a global symbol.
1144 ** GDB values in Python are now callable if the value represents a
1145 function. For example, if 'some_value' represents a function that
1146 takes two integer parameters and returns a value, you can call
1147 that function like so:
1149 result = some_value (10,20)
1151 ** Module gdb.types has been added.
1152 It contains a collection of utilities for working with gdb.Types objects:
1153 get_basic_type, has_field, make_enum_dict.
1155 ** Module gdb.printing has been added.
1156 It contains utilities for writing and registering pretty-printers.
1157 New classes: PrettyPrinter, SubPrettyPrinter,
1158 RegexpCollectionPrettyPrinter.
1159 New function: register_pretty_printer.
1161 ** New commands "info pretty-printers", "enable pretty-printer" and
1162 "disable pretty-printer" have been added.
1164 ** gdb.parameter("directories") is now available.
1166 ** New function gdb.newest_frame returns the newest frame in the
1169 ** The gdb.InferiorThread class has a new "name" attribute. This
1170 holds the thread's name.
1172 ** Python Support for Inferior events.
1173 Python scripts can add observers to be notified of events
1174 occurring in the process being debugged.
1175 The following events are currently supported:
1176 - gdb.events.cont Continue event.
1177 - gdb.events.exited Inferior exited event.
1178 - gdb.events.stop Signal received, and Breakpoint hit events.
1182 ** GDB now puts template parameters in scope when debugging in an
1183 instantiation. For example, if you have:
1185 template<int X> int func (void) { return X; }
1187 then if you step into func<5>, "print X" will show "5". This
1188 feature requires proper debuginfo support from the compiler; it
1189 was added to GCC 4.5.
1191 ** The motion commands "next", "finish", "until", and "advance" now
1192 work better when exceptions are thrown. In particular, GDB will
1193 no longer lose control of the inferior; instead, the GDB will
1194 stop the inferior at the point at which the exception is caught.
1195 This functionality requires a change in the exception handling
1196 code that was introduced in GCC 4.5.
1198 * GDB now follows GCC's rules on accessing volatile objects when
1199 reading or writing target state during expression evaluation.
1200 One notable difference to prior behavior is that "print x = 0"
1201 no longer generates a read of x; the value of the assignment is
1202 now always taken directly from the value being assigned.
1204 * GDB now has some support for using labels in the program's source in
1205 linespecs. For instance, you can use "advance label" to continue
1206 execution to a label.
1208 * GDB now has support for reading and writing a new .gdb_index
1209 section. This section holds a fast index of DWARF debugging
1210 information and can be used to greatly speed up GDB startup and
1211 operation. See the documentation for `save gdb-index' for details.
1213 * The "watch" command now accepts an optional "-location" argument.
1214 When used, this causes GDB to watch the memory referred to by the
1215 expression. Such a watchpoint is never deleted due to it going out
1218 * GDB now supports thread debugging of core dumps on GNU/Linux.
1220 GDB now activates thread debugging using the libthread_db library
1221 when debugging GNU/Linux core dumps, similarly to when debugging
1222 live processes. As a result, when debugging a core dump file, GDB
1223 is now able to display pthread_t ids of threads. For example, "info
1224 threads" shows the same output as when debugging the process when it
1225 was live. In earlier releases, you'd see something like this:
1228 * 1 LWP 6780 main () at main.c:10
1230 While now you see this:
1233 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1235 It is also now possible to inspect TLS variables when debugging core
1238 When debugging a core dump generated on a machine other than the one
1239 used to run GDB, you may need to point GDB at the correct
1240 libthread_db library with the "set libthread-db-search-path"
1241 command. See the user manual for more details on this command.
1243 * When natively debugging programs on PowerPC BookE processors running
1244 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1245 which stop execution of the inferior whenever it executes an instruction
1246 at any address within the specified range. See the "PowerPC Embedded"
1247 section in the user manual for more details.
1249 * New features in the GDB remote stub, GDBserver
1251 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1252 and i686 LynxOS (version 5.x).
1254 ** GDBserver is now supported on Blackfin Linux.
1256 * New native configurations
1258 ia64 HP-UX ia64-*-hpux*
1262 Analog Devices, Inc. Blackfin Processor bfin-*
1264 * Ada task switching is now supported on sparc-elf targets when
1265 debugging a program using the Ravenscar Profile. For more information,
1266 see the "Tasking Support when using the Ravenscar Profile" section
1267 in the GDB user manual.
1269 * Guile support was removed.
1271 * New features in the GNU simulator
1273 ** The --map-info flag lists all known core mappings.
1275 ** CFI flashes may be simulated via the "cfi" device.
1277 *** Changes in GDB 7.2
1279 * Shared library support for remote targets by default
1281 When GDB is configured for a generic, non-OS specific target, like
1282 for example, --target=arm-eabi or one of the many *-*-elf targets,
1283 GDB now queries remote stubs for loaded shared libraries using the
1284 `qXfer:libraries:read' packet. Previously, shared library support
1285 was always disabled for such configurations.
1289 ** Argument Dependent Lookup (ADL)
1291 In C++ ADL lookup directs function search to the namespaces of its
1292 arguments even if the namespace has not been imported.
1302 Here the compiler will search for `foo' in the namespace of 'b'
1303 and find A::foo. GDB now supports this. This construct is commonly
1304 used in the Standard Template Library for operators.
1306 ** Improved User Defined Operator Support
1308 In addition to member operators, GDB now supports lookup of operators
1309 defined in a namespace and imported with a `using' directive, operators
1310 defined in the global scope, operators imported implicitly from an
1311 anonymous namespace, and the ADL operators mentioned in the previous
1313 GDB now also supports proper overload resolution for all the previously
1314 mentioned flavors of operators.
1316 ** static const class members
1318 Printing of static const class members that are initialized in the
1319 class definition has been fixed.
1321 * Windows Thread Information Block access.
1323 On Windows targets, GDB now supports displaying the Windows Thread
1324 Information Block (TIB) structure. This structure is visible either
1325 by using the new command `info w32 thread-information-block' or, by
1326 dereferencing the new convenience variable named `$_tlb', a
1327 thread-specific pointer to the TIB. This feature is also supported
1328 when remote debugging using GDBserver.
1330 * Static tracepoints
1332 Static tracepoints are calls in the user program into a tracing
1333 library. One such library is a port of the LTTng kernel tracer to
1334 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1335 When debugging with GDBserver, GDB now supports combining the GDB
1336 tracepoint machinery with such libraries. For example: the user can
1337 use GDB to probe a static tracepoint marker (a call from the user
1338 program into the tracing library) with the new "strace" command (see
1339 "New commands" below). This creates a "static tracepoint" in the
1340 breakpoint list, that can be manipulated with the same feature set
1341 as fast and regular tracepoints. E.g., collect registers, local and
1342 global variables, collect trace state variables, and define
1343 tracepoint conditions. In addition, the user can collect extra
1344 static tracepoint marker specific data, by collecting the new
1345 $_sdata internal variable. When analyzing the trace buffer, you can
1346 inspect $_sdata like any other variable available to GDB. For more
1347 information, see the "Tracepoints" chapter in GDB user manual. New
1348 remote packets have been defined to support static tracepoints, see
1349 the "New remote packets" section below.
1351 * Better reconstruction of tracepoints after disconnected tracing
1353 GDB will attempt to download the original source form of tracepoint
1354 definitions when starting a trace run, and then will upload these
1355 upon reconnection to the target, resulting in a more accurate
1356 reconstruction of the tracepoints that are in use on the target.
1360 You can now exercise direct control over the ways that GDB can
1361 affect your program. For instance, you can disallow the setting of
1362 breakpoints, so that the program can run continuously (assuming
1363 non-stop mode). In addition, the "observer" variable is available
1364 to switch all of the different controls; in observer mode, GDB
1365 cannot affect the target's behavior at all, which is useful for
1366 tasks like diagnosing live systems in the field.
1368 * The new convenience variable $_thread holds the number of the
1371 * New remote packets
1375 Return the address of the Windows Thread Information Block of a given thread.
1379 In response to several of the tracepoint packets, the target may now
1380 also respond with a number of intermediate `qRelocInsn' request
1381 packets before the final result packet, to have GDB handle
1382 relocating an instruction to execute at a different address. This
1383 is particularly useful for stubs that support fast tracepoints. GDB
1384 reports support for this feature in the qSupported packet.
1388 List static tracepoint markers in the target program.
1392 List static tracepoint markers at a given address in the target
1395 qXfer:statictrace:read
1397 Read the static trace data collected (by a `collect $_sdata'
1398 tracepoint action). The remote stub reports support for this packet
1399 to gdb's qSupported query.
1403 Send the current settings of GDB's permission flags.
1407 Send part of the source (textual) form of a tracepoint definition,
1408 which includes location, conditional, and action list.
1410 * The source command now accepts a -s option to force searching for the
1411 script in the source search path even if the script name specifies
1414 * New features in the GDB remote stub, GDBserver
1416 - GDBserver now support tracepoints (including fast tracepoints, and
1417 static tracepoints). The feature is currently supported by the
1418 i386-linux and amd64-linux builds. See the "Tracepoints support
1419 in gdbserver" section in the manual for more information.
1421 GDBserver JIT compiles the tracepoint's conditional agent
1422 expression bytecode into native code whenever possible for low
1423 overhead dynamic tracepoints conditionals. For such tracepoints,
1424 an expression that examines program state is evaluated when the
1425 tracepoint is reached, in order to determine whether to capture
1426 trace data. If the condition is simple and false, processing the
1427 tracepoint finishes very quickly and no data is gathered.
1429 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1430 for static tracepoints support.
1432 - GDBserver now supports x86_64 Windows 64-bit debugging.
1434 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1435 it understands register description.
1437 * The --batch flag now disables pagination and queries.
1439 * X86 general purpose registers
1441 GDB now supports reading/writing byte, word and double-word x86
1442 general purpose registers directly. This means you can use, say,
1443 $ah or $ax to refer, respectively, to the byte register AH and
1444 16-bit word register AX that are actually portions of the 32-bit
1445 register EAX or 64-bit register RAX.
1447 * The `commands' command now accepts a range of breakpoints to modify.
1448 A plain `commands' following a command that creates multiple
1449 breakpoints affects all the breakpoints set by that command. This
1450 applies to breakpoints set by `rbreak', and also applies when a
1451 single `break' command creates multiple breakpoints (e.g.,
1452 breakpoints on overloaded c++ functions).
1454 * The `rbreak' command now accepts a filename specification as part of
1455 its argument, limiting the functions selected by the regex to those
1456 in the specified file.
1458 * Support for remote debugging Windows and SymbianOS shared libraries
1459 from Unix hosts has been improved. Non Windows GDB builds now can
1460 understand target reported file names that follow MS-DOS based file
1461 system semantics, such as file names that include drive letters and
1462 use the backslash character as directory separator. This makes it
1463 possible to transparently use the "set sysroot" and "set
1464 solib-search-path" on Unix hosts to point as host copies of the
1465 target's shared libraries. See the new command "set
1466 target-file-system-kind" described below, and the "Commands to
1467 specify files" section in the user manual for more information.
1471 eval template, expressions...
1472 Convert the values of one or more expressions under the control
1473 of the string template to a command line, and call it.
1475 set target-file-system-kind unix|dos-based|auto
1476 show target-file-system-kind
1477 Set or show the assumed file system kind for target reported file
1480 save breakpoints <filename>
1481 Save all current breakpoint definitions to a file suitable for use
1482 in a later debugging session. To read the saved breakpoint
1483 definitions, use the `source' command.
1485 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1488 info static-tracepoint-markers
1489 Display information about static tracepoint markers in the target.
1491 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1492 Define a static tracepoint by probing a marker at the given
1493 function, line, address, or marker ID.
1497 Enable and disable observer mode.
1499 set may-write-registers on|off
1500 set may-write-memory on|off
1501 set may-insert-breakpoints on|off
1502 set may-insert-tracepoints on|off
1503 set may-insert-fast-tracepoints on|off
1504 set may-interrupt on|off
1505 Set individual permissions for GDB effects on the target. Note that
1506 some of these settings can have undesirable or surprising
1507 consequences, particularly when changed in the middle of a session.
1508 For instance, disabling the writing of memory can prevent
1509 breakpoints from being inserted, cause single-stepping to fail, or
1510 even crash your program, if you disable after breakpoints have been
1511 inserted. However, GDB should not crash.
1513 set record memory-query on|off
1514 show record memory-query
1515 Control whether to stop the inferior if memory changes caused
1516 by an instruction cannot be recorded.
1521 The disassemble command now supports "start,+length" form of two arguments.
1525 ** GDB now provides a new directory location, called the python directory,
1526 where Python scripts written for GDB can be installed. The location
1527 of that directory is <data-directory>/python, where <data-directory>
1528 is the GDB data directory. For more details, see section `Scripting
1529 GDB using Python' in the manual.
1531 ** The GDB Python API now has access to breakpoints, symbols, symbol
1532 tables, program spaces, inferiors, threads and frame's code blocks.
1533 Additionally, GDB Parameters can now be created from the API, and
1534 manipulated via set/show in the CLI.
1536 ** New functions gdb.target_charset, gdb.target_wide_charset,
1537 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1539 ** New exception gdb.GdbError.
1541 ** Pretty-printers are now also looked up in the current program space.
1543 ** Pretty-printers can now be individually enabled and disabled.
1545 ** GDB now looks for names of Python scripts to auto-load in a
1546 special section named `.debug_gdb_scripts', in addition to looking
1547 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1549 * Tracepoint actions were unified with breakpoint commands. In particular,
1550 there are no longer differences in "info break" output for breakpoints and
1551 tracepoints and the "commands" command can be used for both tracepoints and
1552 regular breakpoints.
1556 ARM Symbian arm*-*-symbianelf*
1558 * D language support.
1559 GDB now supports debugging programs written in the D programming
1562 * GDB now supports the extended ptrace interface for PowerPC which is
1563 available since Linux kernel version 2.6.34. This automatically enables
1564 any hardware breakpoints and additional hardware watchpoints available in
1565 the processor. The old ptrace interface exposes just one hardware
1566 watchpoint and no hardware breakpoints.
1568 * GDB is now able to use the Data Value Compare (DVC) register available on
1569 embedded PowerPC processors to implement in hardware simple watchpoint
1570 conditions of the form:
1572 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1574 This works in native GDB running on Linux kernels with the extended ptrace
1575 interface mentioned above.
1577 *** Changes in GDB 7.1
1581 ** Namespace Support
1583 GDB now supports importing of namespaces in C++. This enables the
1584 user to inspect variables from imported namespaces. Support for
1585 namepace aliasing has also been added. So, if a namespace is
1586 aliased in the current scope (e.g. namepace C=A; ) the user can
1587 print variables using the alias (e.g. (gdb) print C::x).
1591 All known bugs relating to the printing of virtual base class were
1592 fixed. It is now possible to call overloaded static methods using a
1597 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1598 and reinterpret_cast<> are now handled by the C++ expression parser.
1602 Xilinx MicroBlaze microblaze-*-*
1607 Xilinx MicroBlaze microblaze
1610 * Multi-program debugging.
1612 GDB now has support for multi-program (a.k.a. multi-executable or
1613 multi-exec) debugging. This allows for debugging multiple inferiors
1614 simultaneously each running a different program under the same GDB
1615 session. See "Debugging Multiple Inferiors and Programs" in the
1616 manual for more information. This implied some user visible changes
1617 in the multi-inferior support. For example, "info inferiors" now
1618 lists inferiors that are not running yet or that have exited
1619 already. See also "New commands" and "New options" below.
1621 * New tracing features
1623 GDB's tracepoint facility now includes several new features:
1625 ** Trace state variables
1627 GDB tracepoints now include support for trace state variables, which
1628 are variables managed by the target agent during a tracing
1629 experiment. They are useful for tracepoints that trigger each
1630 other, so for instance one tracepoint can count hits in a variable,
1631 and then a second tracepoint has a condition that is true when the
1632 count reaches a particular value. Trace state variables share the
1633 $-syntax of GDB convenience variables, and can appear in both
1634 tracepoint actions and condition expressions. Use the "tvariable"
1635 command to create, and "info tvariables" to view; see "Trace State
1636 Variables" in the manual for more detail.
1640 GDB now includes an option for defining fast tracepoints, which
1641 targets may implement more efficiently, such as by installing a jump
1642 into the target agent rather than a trap instruction. The resulting
1643 speedup can be by two orders of magnitude or more, although the
1644 tradeoff is that some program locations on some target architectures
1645 might not allow fast tracepoint installation, for instance if the
1646 instruction to be replaced is shorter than the jump. To request a
1647 fast tracepoint, use the "ftrace" command, with syntax identical to
1648 the regular trace command.
1650 ** Disconnected tracing
1652 It is now possible to detach GDB from the target while it is running
1653 a trace experiment, then reconnect later to see how the experiment
1654 is going. In addition, a new variable disconnected-tracing lets you
1655 tell the target agent whether to continue running a trace if the
1656 connection is lost unexpectedly.
1660 GDB now has the ability to save the trace buffer into a file, and
1661 then use that file as a target, similarly to you can do with
1662 corefiles. You can select trace frames, print data that was
1663 collected in them, and use tstatus to display the state of the
1664 tracing run at the moment that it was saved. To create a trace
1665 file, use "tsave <filename>", and to use it, do "target tfile
1668 ** Circular trace buffer
1670 You can ask the target agent to handle the trace buffer as a
1671 circular buffer, discarding the oldest trace frames to make room for
1672 newer ones, by setting circular-trace-buffer to on. This feature may
1673 not be available for all target agents.
1678 The disassemble command, when invoked with two arguments, now requires
1679 the arguments to be comma-separated.
1682 The info variables command now displays variable definitions. Files
1683 which only declare a variable are not shown.
1686 The source command is now capable of sourcing Python scripts.
1687 This feature is dependent on the debugger being build with Python
1690 Related to this enhancement is also the introduction of a new command
1691 "set script-extension" (see below).
1693 * New commands (for set/show, see "New options" below)
1695 record save [<FILENAME>]
1696 Save a file (in core file format) containing the process record
1697 execution log for replay debugging at a later time.
1699 record restore <FILENAME>
1700 Restore the process record execution log that was saved at an
1701 earlier time, for replay debugging.
1703 add-inferior [-copies <N>] [-exec <FILENAME>]
1706 clone-inferior [-copies <N>] [ID]
1707 Make a new inferior ready to execute the same program another
1708 inferior has loaded.
1713 maint info program-spaces
1714 List the program spaces loaded into GDB.
1716 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1717 show remote interrupt-sequence
1718 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1719 as the sequence to the remote target in order to interrupt the execution.
1720 Ctrl-C is a default. Some system prefers BREAK which is high level of
1721 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1722 Magic SysRq g. It is BREAK signal and character 'g'.
1724 set remote interrupt-on-connect [on | off]
1725 show remote interrupt-on-connect
1726 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1727 remote target when gdb connects to it. This is needed when you debug
1730 set remotebreak [on | off]
1732 Deprecated. Use "set/show remote interrupt-sequence" instead.
1734 tvariable $NAME [ = EXP ]
1735 Create or modify a trace state variable.
1738 List trace state variables and their values.
1740 delete tvariable $NAME ...
1741 Delete one or more trace state variables.
1744 Evaluate the given expressions without collecting anything into the
1745 trace buffer. (Valid in tracepoint actions only.)
1747 ftrace FN / FILE:LINE / *ADDR
1748 Define a fast tracepoint at the given function, line, or address.
1750 * New expression syntax
1752 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1753 GDB now parses 0b101010 identically with 42.
1757 set follow-exec-mode new|same
1758 show follow-exec-mode
1759 Control whether GDB reuses the same inferior across an exec call or
1760 creates a new one. This is useful to be able to restart the old
1761 executable after the inferior having done an exec call.
1763 set default-collect EXPR, ...
1764 show default-collect
1765 Define a list of expressions to be collected at each tracepoint.
1766 This is a useful way to ensure essential items are not overlooked,
1767 such as registers or a critical global variable.
1769 set disconnected-tracing
1770 show disconnected-tracing
1771 If set to 1, the target is instructed to continue tracing if it
1772 loses its connection to GDB. If 0, the target is to stop tracing
1775 set circular-trace-buffer
1776 show circular-trace-buffer
1777 If set to on, the target is instructed to use a circular trace buffer
1778 and discard the oldest trace frames instead of stopping the trace due
1779 to a full trace buffer. If set to off, the trace stops when the buffer
1780 fills up. Some targets may not support this.
1782 set script-extension off|soft|strict
1783 show script-extension
1784 If set to "off", the debugger does not perform any script language
1785 recognition, and all sourced files are assumed to be GDB scripts.
1786 If set to "soft" (the default), files are sourced according to
1787 filename extension, falling back to GDB scripts if the first
1789 If set to "strict", files are sourced according to filename extension.
1791 set ada trust-PAD-over-XVS on|off
1792 show ada trust-PAD-over-XVS
1793 If off, activate a workaround against a bug in the debugging information
1794 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1795 the GCC sources for more information about the GNAT encoding and
1796 PAD types in particular). It is always safe to set this option to
1797 off, but this introduces a slight performance penalty. The default
1800 * Python API Improvements
1802 ** GDB provides the new class gdb.LazyString. This is useful in
1803 some pretty-printing cases. The new method gdb.Value.lazy_string
1804 provides a simple way to create objects of this type.
1806 ** The fields returned by gdb.Type.fields now have an
1807 `is_base_class' attribute.
1809 ** The new method gdb.Type.range returns the range of an array type.
1811 ** The new method gdb.parse_and_eval can be used to parse and
1812 evaluate an expression.
1814 * New remote packets
1817 Define a trace state variable.
1820 Get the current value of a trace state variable.
1823 Set desired tracing behavior upon disconnection.
1826 Set the trace buffer to be linear or circular.
1829 Get data about the tracepoints currently in use.
1833 Process record now works correctly with hardware watchpoints.
1835 Multiple bug fixes have been made to the mips-irix port, making it
1836 much more reliable. In particular:
1837 - Debugging threaded applications is now possible again. Previously,
1838 GDB would hang while starting the program, or while waiting for
1839 the program to stop at a breakpoint.
1840 - Attaching to a running process no longer hangs.
1841 - An error occurring while loading a core file has been fixed.
1842 - Changing the value of the PC register now works again. This fixes
1843 problems observed when using the "jump" command, or when calling
1844 a function from GDB, or even when assigning a new value to $pc.
1845 - With the "finish" and "return" commands, the return value for functions
1846 returning a small array is now correctly printed.
1847 - It is now possible to break on shared library code which gets executed
1848 during a shared library init phase (code executed while executing
1849 their .init section). Previously, the breakpoint would have no effect.
1850 - GDB is now able to backtrace through the signal handler for
1851 non-threaded programs.
1853 PIE (Position Independent Executable) programs debugging is now supported.
1854 This includes debugging execution of PIC (Position Independent Code) shared
1855 libraries although for that, it should be possible to run such libraries as an
1858 *** Changes in GDB 7.0
1860 * GDB now has an interface for JIT compilation. Applications that
1861 dynamically generate code can create symbol files in memory and register
1862 them with GDB. For users, the feature should work transparently, and
1863 for JIT developers, the interface is documented in the GDB manual in the
1864 "JIT Compilation Interface" chapter.
1866 * Tracepoints may now be conditional. The syntax is as for
1867 breakpoints; either an "if" clause appended to the "trace" command,
1868 or the "condition" command is available. GDB sends the condition to
1869 the target for evaluation using the same bytecode format as is used
1870 for tracepoint actions.
1872 * The disassemble command now supports: an optional /r modifier, print the
1873 raw instructions in hex as well as in symbolic form, and an optional /m
1874 modifier to print mixed source+assembly.
1876 * Process record and replay
1878 In a architecture environment that supports ``process record and
1879 replay'', ``process record and replay'' target can record a log of
1880 the process execution, and replay it with both forward and reverse
1883 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1884 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1885 set execution-direction {forward|reverse}, for targets that support
1888 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1889 feature is available with a native GDB running on kernel version
1892 * GDB now has support for multi-byte and wide character sets on the
1893 target. Strings whose character type is wchar_t, char16_t, or
1894 char32_t are now correctly printed. GDB supports wide- and unicode-
1895 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1896 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1897 `printf'. This feature requires iconv to work properly; if your
1898 system does not have a working iconv, GDB can use GNU libiconv. See
1899 the installation instructions for more information.
1901 * GDB now supports automatic retrieval of shared library files from
1902 remote targets. To use this feature, specify a system root that begins
1903 with the `remote:' prefix, either via the `set sysroot' command or via
1904 the `--with-sysroot' configure-time option.
1906 * "info sharedlibrary" now takes an optional regex of libraries to show,
1907 and it now reports if a shared library has no debugging information.
1909 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1910 now complete on file names.
1912 * When completing in expressions, gdb will attempt to limit
1913 completions to allowable structure or union fields, where appropriate.
1914 For instance, consider:
1916 # struct example { int f1; double f2; };
1917 # struct example variable;
1920 If the user types TAB at the end of this command line, the available
1921 completions will be "f1" and "f2".
1923 * Inlined functions are now supported. They show up in backtraces, and
1924 the "step", "next", and "finish" commands handle them automatically.
1926 * GDB now supports the token-splicing (##) and stringification (#)
1927 operators when expanding macros. It also supports variable-arity
1930 * GDB now supports inspecting extra signal information, exported by
1931 the new $_siginfo convenience variable. The feature is currently
1932 implemented on linux ARM, i386 and amd64.
1934 * GDB can now display the VFP floating point registers and NEON vector
1935 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1936 can provide these registers (requires Linux 2.6.30 or later). Remote
1937 and simulator targets may also provide them.
1939 * New remote packets
1942 Search memory for a sequence of bytes.
1945 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1946 operation over reliable transport links. Use of this packet is
1947 controlled by the `set remote noack-packet' command.
1950 Kill the process with the specified process ID. Use this in preference
1951 to `k' when multiprocess protocol extensions are supported.
1954 Obtains additional operating system information
1958 Read or write additional signal information.
1960 * Removed remote protocol undocumented extension
1962 An undocumented extension to the remote protocol's `S' stop reply
1963 packet that permited the stub to pass a process id was removed.
1964 Remote servers should use the `T' stop reply packet instead.
1966 * GDB now supports multiple function calling conventions according to the
1967 DWARF-2 DW_AT_calling_convention function attribute.
1969 * The SH target utilizes the aforementioned change to distinguish between gcc
1970 and Renesas calling convention. It also adds the new CLI commands
1971 `set/show sh calling-convention'.
1973 * GDB can now read compressed debug sections, as produced by GNU gold
1974 with the --compress-debug-sections=zlib flag.
1976 * 64-bit core files are now supported on AIX.
1978 * Thread switching is now supported on Tru64.
1980 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1981 which will be allocated using malloc later in program execution.
1983 * The qXfer:libraries:read remote procotol packet now allows passing a
1984 list of section offsets.
1986 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1987 conditions handling signals delivered during attach or thread creation
1988 have also been fixed.
1990 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1991 From the user's standpoint, all unqualified instances of True and False
1992 are treated as the standard definitions, regardless of context.
1994 * GDB now parses C++ symbol and type names more flexibly. For
1997 template<typename T> class C { };
2000 GDB will now correctly handle all of:
2002 ptype C<char const *>
2003 ptype C<char const*>
2004 ptype C<const char *>
2005 ptype C<const char*>
2007 * New features in the GDB remote stub, gdbserver
2009 - The "--wrapper" command-line argument tells gdbserver to use a
2010 wrapper program to launch programs for debugging.
2012 - On PowerPC and S/390 targets, it is now possible to use a single
2013 gdbserver executable to debug both 32-bit and 64-bit programs.
2014 (This requires gdbserver itself to be built as a 64-bit executable.)
2016 - gdbserver uses the new noack protocol mode for TCP connections to
2017 reduce communications latency, if also supported and enabled in GDB.
2019 - Support for the sparc64-linux-gnu target is now included in
2022 - The amd64-linux build of gdbserver now supports debugging both
2023 32-bit and 64-bit programs.
2025 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2026 now support hardware watchpoints, and will use them automatically
2031 GDB now has support for scripting using Python. Whether this is
2032 available is determined at configure time.
2034 New GDB commands can now be written in Python.
2036 * Ada tasking support
2038 Ada tasks can now be inspected in GDB. The following commands have
2042 Print the list of Ada tasks.
2044 Print detailed information about task number N.
2046 Print the task number of the current task.
2048 Switch the context of debugging to task number N.
2050 * Support for user-defined prefixed commands. The "define" command can
2051 add new commands to existing prefixes, e.g. "target".
2053 * Multi-inferior, multi-process debugging.
2055 GDB now has generalized support for multi-inferior debugging. See
2056 "Debugging Multiple Inferiors" in the manual for more information.
2057 Although availability still depends on target support, the command
2058 set is more uniform now. The GNU/Linux specific multi-forks support
2059 has been migrated to this new framework. This implied some user
2060 visible changes; see "New commands" and also "Removed commands"
2063 * Target descriptions can now describe the target OS ABI. See the
2064 "Target Description Format" section in the user manual for more
2067 * Target descriptions can now describe "compatible" architectures
2068 to indicate that the target can execute applications for a different
2069 architecture in addition to those for the main target architecture.
2070 See the "Target Description Format" section in the user manual for
2073 * Multi-architecture debugging.
2075 GDB now includes general supports for debugging applications on
2076 hybrid systems that use more than one single processor architecture
2077 at the same time. Each such hybrid architecture still requires
2078 specific support to be added. The only hybrid architecture supported
2079 in this version of GDB is the Cell Broadband Engine.
2081 * GDB now supports integrated debugging of Cell/B.E. applications that
2082 use both the PPU and SPU architectures. To enable support for hybrid
2083 Cell/B.E. debugging, you need to configure GDB to support both the
2084 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2085 --enable-targets configure option.
2087 * Non-stop mode debugging.
2089 For some targets, GDB now supports an optional mode of operation in
2090 which you can examine stopped threads while other threads continue
2091 to execute freely. This is referred to as non-stop mode, with the
2092 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2093 section in the user manual for more information.
2095 To be able to support remote non-stop debugging, a remote stub needs
2096 to implement the non-stop mode remote protocol extensions, as
2097 described in the "Remote Non-Stop" section of the user manual. The
2098 GDB remote stub, gdbserver, has been adjusted to support these
2099 extensions on linux targets.
2101 * New commands (for set/show, see "New options" below)
2103 catch syscall [NAME(S) | NUMBER(S)]
2104 Catch system calls. Arguments, which should be names of system
2105 calls or their numbers, mean catch only those syscalls. Without
2106 arguments, every syscall will be caught. When the inferior issues
2107 any of the specified syscalls, GDB will stop and announce the system
2108 call, both when it is called and when its call returns. This
2109 feature is currently available with a native GDB running on the
2110 Linux Kernel, under the following architectures: x86, x86_64,
2111 PowerPC and PowerPC64.
2113 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2115 Search memory for a sequence of bytes.
2117 maint set python print-stack
2118 maint show python print-stack
2119 Show a stack trace when an error is encountered in a Python script.
2122 Invoke CODE by passing it to the Python interpreter.
2127 These allow macros to be defined, undefined, and listed
2131 Show operating system information about processes.
2134 List the inferiors currently under GDB's control.
2137 Switch focus to inferior number NUM.
2140 Detach from inferior number NUM.
2143 Kill inferior number NUM.
2147 set spu stop-on-load
2148 show spu stop-on-load
2149 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2151 set spu auto-flush-cache
2152 show spu auto-flush-cache
2153 Control whether to automatically flush the software-managed cache
2154 during Cell/B.E. debugging.
2156 set sh calling-convention
2157 show sh calling-convention
2158 Control the calling convention used when calling SH target functions.
2161 show debug timestamp
2162 Control display of timestamps with GDB debugging output.
2164 set disassemble-next-line
2165 show disassemble-next-line
2166 Control display of disassembled source lines or instructions when
2169 set remote noack-packet
2170 show remote noack-packet
2171 Set/show the use of remote protocol QStartNoAckMode packet. See above
2172 under "New remote packets."
2174 set remote query-attached-packet
2175 show remote query-attached-packet
2176 Control use of remote protocol `qAttached' (query-attached) packet.
2178 set remote read-siginfo-object
2179 show remote read-siginfo-object
2180 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2183 set remote write-siginfo-object
2184 show remote write-siginfo-object
2185 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2188 set remote reverse-continue
2189 show remote reverse-continue
2190 Control use of remote protocol 'bc' (reverse-continue) packet.
2192 set remote reverse-step
2193 show remote reverse-step
2194 Control use of remote protocol 'bs' (reverse-step) packet.
2196 set displaced-stepping
2197 show displaced-stepping
2198 Control displaced stepping mode. Displaced stepping is a way to
2199 single-step over breakpoints without removing them from the debuggee.
2200 Also known as "out-of-line single-stepping".
2203 show debug displaced
2204 Control display of debugging info for displaced stepping.
2206 maint set internal-error
2207 maint show internal-error
2208 Control what GDB does when an internal error is detected.
2210 maint set internal-warning
2211 maint show internal-warning
2212 Control what GDB does when an internal warning is detected.
2217 Use a wrapper program to launch programs for debugging.
2219 set multiple-symbols (all|ask|cancel)
2220 show multiple-symbols
2221 The value of this variable can be changed to adjust the debugger behavior
2222 when an expression or a breakpoint location contains an ambiguous symbol
2223 name (an overloaded function name, for instance).
2225 set breakpoint always-inserted
2226 show breakpoint always-inserted
2227 Keep breakpoints always inserted in the target, as opposed to inserting
2228 them when resuming the target, and removing them when the target stops.
2229 This option can improve debugger performance on slow remote targets.
2231 set arm fallback-mode (arm|thumb|auto)
2232 show arm fallback-mode
2233 set arm force-mode (arm|thumb|auto)
2235 These commands control how ARM GDB determines whether instructions
2236 are ARM or Thumb. The default for both settings is auto, which uses
2237 the current CPSR value for instructions without symbols; previous
2238 versions of GDB behaved as if "set arm fallback-mode arm".
2240 set disable-randomization
2241 show disable-randomization
2242 Standalone programs run with the virtual address space randomization enabled
2243 by default on some platforms. This option keeps the addresses stable across
2244 multiple debugging sessions.
2248 Control whether other threads are stopped or not when some thread hits
2253 Requests that asynchronous execution is enabled in the target, if available.
2254 In this case, it's possible to resume target in the background, and interact
2255 with GDB while the target is running. "show target-async" displays the
2256 current state of asynchronous execution of the target.
2258 set target-wide-charset
2259 show target-wide-charset
2260 The target-wide-charset is the name of the character set that GDB
2261 uses when printing characters whose type is wchar_t.
2263 set tcp auto-retry (on|off)
2265 set tcp connect-timeout
2266 show tcp connect-timeout
2267 These commands allow GDB to retry failed TCP connections to a remote stub
2268 with a specified timeout period; this is useful if the stub is launched
2269 in parallel with GDB but may not be ready to accept connections immediately.
2271 set libthread-db-search-path
2272 show libthread-db-search-path
2273 Control list of directories which GDB will search for appropriate
2276 set schedule-multiple (on|off)
2277 show schedule-multiple
2278 Allow GDB to resume all threads of all processes or only threads of
2279 the current process.
2283 Use more aggressive caching for accesses to the stack. This improves
2284 performance of remote debugging (particularly backtraces) without
2285 affecting correctness.
2287 set interactive-mode (on|off|auto)
2288 show interactive-mode
2289 Control whether GDB runs in interactive mode (on) or not (off).
2290 When in interactive mode, GDB waits for the user to answer all
2291 queries. Otherwise, GDB does not wait and assumes the default
2292 answer. When set to auto (the default), GDB determines which
2293 mode to use based on the stdin settings.
2298 For program forks, this is replaced by the new more generic `info
2299 inferiors' command. To list checkpoints, you can still use the
2300 `info checkpoints' command, which was an alias for the `info forks'
2304 Replaced by the new `inferior' command. To switch between
2305 checkpoints, you can still use the `restart' command, which was an
2306 alias for the `fork' command.
2309 This is removed, since some targets don't have a notion of
2310 processes. To switch between processes, you can still use the
2311 `inferior' command using GDB's own inferior number.
2314 For program forks, this is replaced by the new more generic `kill
2315 inferior' command. To delete a checkpoint, you can still use the
2316 `delete checkpoint' command, which was an alias for the `delete
2320 For program forks, this is replaced by the new more generic `detach
2321 inferior' command. To detach a checkpoint, you can still use the
2322 `detach checkpoint' command, which was an alias for the `detach
2325 * New native configurations
2327 x86/x86_64 Darwin i[34567]86-*-darwin*
2329 x86_64 MinGW x86_64-*-mingw*
2333 Lattice Mico32 lm32-*
2334 x86 DICOS i[34567]86-*-dicos*
2335 x86_64 DICOS x86_64-*-dicos*
2338 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2339 (mingw32ce) debugging.
2345 These commands were actually not implemented on any target.
2347 *** Changes in GDB 6.8
2349 * New native configurations
2351 NetBSD/hppa hppa*-*netbsd*
2352 Xtensa GNU/Linux xtensa*-*-linux*
2356 NetBSD/hppa hppa*-*-netbsd*
2357 Xtensa GNU/Lunux xtensa*-*-linux*
2359 * Change in command line behavior -- corefiles vs. process ids.
2361 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2362 attaching to process NUMBER fails, GDB no longer attempts to open a
2363 core file named NUMBER. Attaching to a program using the -c option
2364 is no longer supported. Instead, use the '-p' or '--pid' options.
2366 * GDB can now be built as a native debugger for debugging Windows x86
2367 (mingw32) Portable Executable (PE) programs.
2369 * Pending breakpoints no longer change their number when their address
2372 * GDB now supports breakpoints with multiple locations,
2373 including breakpoints on C++ constructors, inside C++ templates,
2374 and in inlined functions.
2376 * GDB's ability to debug optimized code has been improved. GDB more
2377 accurately identifies function bodies and lexical blocks that occupy
2378 more than one contiguous range of addresses.
2380 * Target descriptions can now describe registers for PowerPC.
2382 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2383 registers on PowerPC targets.
2385 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2386 targets even when the libthread_db library is not available.
2388 * The GDB remote stub, gdbserver, now supports the new file transfer
2389 commands (remote put, remote get, and remote delete).
2391 * The GDB remote stub, gdbserver, now supports run and attach in
2392 extended-remote mode.
2394 * hppa*64*-*-hpux11* target broken
2395 The debugger is unable to start a program and fails with the following
2396 error: "Error trying to get information about dynamic linker".
2397 The gdb-6.7 release is also affected.
2399 * GDB now supports the --enable-targets= configure option to allow
2400 building a single GDB executable that supports multiple remote
2401 target architectures.
2403 * GDB now supports debugging C and C++ programs which use the
2404 Decimal Floating Point extension. In addition, the PowerPC target
2405 now has a set of pseudo-registers to inspect decimal float values
2406 stored in two consecutive float registers.
2408 * The -break-insert MI command can optionally create pending
2411 * Improved support for debugging Ada
2412 Many improvements to the Ada language support have been made. These
2414 - Better support for Ada2005 interface types
2415 - Improved handling of arrays and slices in general
2416 - Better support for Taft-amendment types
2417 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2419 - Improved command completion in Ada
2422 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2427 set print frame-arguments (all|scalars|none)
2428 show print frame-arguments
2429 The value of this variable can be changed to control which argument
2430 values should be printed by the debugger when displaying a frame.
2435 Transfer files to and from a remote target, and delete remote files.
2442 Transfer files to and from a remote target, and delete remote files.
2444 * New remote packets
2451 Open, close, read, write, and delete files on the remote system.
2454 Attach to an existing process on the remote system, in extended-remote
2458 Run a new process on the remote system, in extended-remote mode.
2460 *** Changes in GDB 6.7
2462 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2463 bfd, libiberty and opcodes, as revealed by static analysis donated by
2464 Coverity, Inc. (http://scan.coverity.com).
2466 * When looking up multiply-defined global symbols, GDB will now prefer the
2467 symbol definition in the current shared library if it was built using the
2468 -Bsymbolic linker option.
2470 * When the Text User Interface (TUI) is not configured, GDB will now
2471 recognize the -tui command-line option and print a message that the TUI
2474 * The GDB remote stub, gdbserver, now has lower overhead for high
2475 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2477 * GDB for MIPS targets now autodetects whether a remote target provides
2478 32-bit or 64-bit register values.
2480 * Support for C++ member pointers has been improved.
2482 * GDB now understands XML target descriptions, which specify the
2483 target's overall architecture. GDB can read a description from
2484 a local file or over the remote serial protocol.
2486 * Vectors of single-byte data use a new integer type which is not
2487 automatically displayed as character or string data.
2489 * The /s format now works with the print command. It displays
2490 arrays of single-byte integers and pointers to single-byte integers
2493 * Target descriptions can now describe target-specific registers,
2494 for architectures which have implemented the support (currently
2495 only ARM, M68K, and MIPS).
2497 * GDB and the GDB remote stub, gdbserver, now support the XScale
2500 * The GDB remote stub, gdbserver, has been updated to support
2501 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2502 has been rewritten to use the standard GDB remote protocol.
2504 * GDB can now step into C++ functions which are called through thunks.
2506 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2508 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2509 layout. It also supports a TextSeg= and DataSeg= response when only
2510 segment base addresses (rather than offsets) are available.
2512 * The /i format now outputs any trailing branch delay slot instructions
2513 immediately following the last instruction within the count specified.
2515 * The GDB remote protocol "T" stop reply packet now supports a
2516 "library" response. Combined with the new "qXfer:libraries:read"
2517 packet, this response allows GDB to debug shared libraries on targets
2518 where the operating system manages the list of loaded libraries (e.g.
2519 Windows and SymbianOS).
2521 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2522 (DLLs) on Windows and Windows CE targets.
2524 * GDB now supports a faster verification that a .debug file matches its binary
2525 according to its build-id signature, if the signature is present.
2531 Enable or disable hardware flow control (RTS/CTS) on the serial port
2532 when debugging using remote targets.
2534 set mem inaccessible-by-default
2535 show mem inaccessible-by-default
2536 If the target supplies a memory map, for instance via the remote
2537 protocol's "qXfer:memory-map:read" packet, setting this variable
2538 prevents GDB from accessing memory outside the memory map. This
2539 is useful for targets with memory mapped registers or which react
2540 badly to accesses of unmapped address space.
2542 set breakpoint auto-hw
2543 show breakpoint auto-hw
2544 If the target supplies a memory map, for instance via the remote
2545 protocol's "qXfer:memory-map:read" packet, setting this variable
2546 lets GDB use hardware breakpoints automatically for memory regions
2547 where it can not use software breakpoints. This covers both the
2548 "break" command and internal breakpoints used for other commands
2549 including "next" and "finish".
2552 catch exception unhandled
2553 Stop the program execution when Ada exceptions are raised.
2556 Stop the program execution when an Ada assertion failed.
2560 Set an alternate system root for target files. This is a more
2561 general version of "set solib-absolute-prefix", which is now
2562 an alias to "set sysroot".
2565 Provide extended SPU facility status information. This set of
2566 commands is available only when debugging the Cell/B.E. SPU
2569 * New native configurations
2571 OpenBSD/sh sh*-*openbsd*
2574 unset tdesc filename
2576 Use the specified local file as an XML target description, and do
2577 not query the target for its built-in description.
2581 OpenBSD/sh sh*-*-openbsd*
2582 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2583 Toshiba Media Processor mep-elf
2585 * New remote packets
2588 Ignore the specified signals; pass them directly to the debugged program
2589 without stopping other threads or reporting them to GDB.
2591 qXfer:features:read:
2592 Read an XML target description from the target, which describes its
2597 Read or write contents of an spufs file on the target system. These
2598 packets are available only on the Cell/B.E. SPU architecture.
2600 qXfer:libraries:read:
2601 Report the loaded shared libraries. Combined with new "T" packet
2602 response, this packet allows GDB to debug shared libraries on
2603 targets where the operating system manages the list of loaded
2604 libraries (e.g. Windows and SymbianOS).
2608 Support for these obsolete configurations has been removed.
2616 i[34567]86-*-lynxos*
2617 i[34567]86-*-netware*
2618 i[34567]86-*-sco3.2v5*
2619 i[34567]86-*-sco3.2v4*
2621 i[34567]86-*-sysv4.2*
2624 i[34567]86-*-unixware2*
2625 i[34567]86-*-unixware*
2634 * Other removed features
2641 Various m68k-only ROM monitors.
2648 Various Renesas ROM monitors and debugging interfaces for SH and
2653 Support for a Macraigor serial interface to on-chip debugging.
2654 GDB does not directly support the newer parallel or USB
2659 A debug information format. The predecessor to DWARF 2 and
2660 DWARF 3, which are still supported.
2662 Support for the HP aCC compiler on HP-UX/PA-RISC
2664 SOM-encapsulated symbolic debugging information, automatic
2665 invocation of pxdb, and the aCC custom C++ ABI. This does not
2666 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2667 with aCC can still be debugged on an assembly level.
2669 MIPS ".pdr" sections
2671 A MIPS-specific format used to describe stack frame layout
2672 in debugging information.
2676 GDB could work with an older version of Guile to debug
2677 the interpreter and Scheme programs running in it.
2679 set mips stack-arg-size
2680 set mips saved-gpreg-size
2682 Use "set mips abi" to control parameter passing for MIPS.
2684 *** Changes in GDB 6.6
2689 Cell Broadband Engine SPU spu-elf
2691 * GDB can now be configured as a cross-debugger targeting native Windows
2692 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2693 running on a Windows system over TCP/IP to debug Windows programs.
2695 * The GDB remote stub, gdbserver, has been updated to support Windows and
2696 Cygwin debugging. Both single-threaded and multi-threaded programs are
2699 * The "set trust-readonly-sections" command works again. This command was
2700 broken in GDB 6.3, 6.4, and 6.5.
2702 * The "load" command now supports writing to flash memory, if the remote
2703 stub provides the required support.
2705 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2706 longer requires symbolic debug information (e.g. DWARF-2).
2711 unset substitute-path
2712 show substitute-path
2713 Manage a list of substitution rules that GDB uses to rewrite the name
2714 of the directories where the sources are located. This can be useful
2715 for instance when the sources were moved to a different location
2716 between compilation and debugging.
2720 Print each CLI command as it is executed. Each command is prefixed with
2721 a number of `+' symbols representing the nesting depth.
2722 The source command now has a `-v' option to enable the same feature.
2726 The ARM Demon monitor support (RDP protocol, "target rdp").
2728 Kernel Object Display, an embedded debugging feature which only worked with
2729 an obsolete version of Cisco IOS.
2731 The 'set download-write-size' and 'show download-write-size' commands.
2733 * New remote packets
2736 Tell a stub about GDB client features, and request remote target features.
2737 The first feature implemented is PacketSize, which allows the target to
2738 specify the size of packets it can handle - to minimize the number of
2739 packets required and improve performance when connected to a remote
2743 Fetch an OS auxilliary vector from the remote stub. This packet is a
2744 more efficient replacement for qPart:auxv:read.
2746 qXfer:memory-map:read:
2747 Fetch a memory map from the remote stub, including information about
2748 RAM, ROM, and flash memory devices.
2753 Erase and program a flash memory device.
2755 * Removed remote packets
2758 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2759 used it, and only gdbserver implemented it.
2761 *** Changes in GDB 6.5
2765 Renesas M32C/M16C m32c-elf
2767 Morpho Technologies ms1 ms1-elf
2771 init-if-undefined Initialize a convenience variable, but
2772 only if it doesn't already have a value.
2774 The following commands are presently only implemented for native GNU/Linux:
2776 checkpoint Save a snapshot of the program state.
2778 restart <n> Return the program state to a
2779 previously saved state.
2781 info checkpoints List currently saved checkpoints.
2783 delete-checkpoint <n> Delete a previously saved checkpoint.
2785 set|show detach-on-fork Tell gdb whether to detach from a newly
2786 forked process, or to keep debugging it.
2788 info forks List forks of the user program that
2789 are available to be debugged.
2791 fork <n> Switch to debugging one of several
2792 forks of the user program that are
2793 available to be debugged.
2795 delete-fork <n> Delete a fork from the list of forks
2796 that are available to be debugged (and
2797 kill the forked process).
2799 detach-fork <n> Delete a fork from the list of forks
2800 that are available to be debugged (and
2801 allow the process to continue).
2805 Morpho Technologies ms2 ms1-elf
2807 * Improved Windows host support
2809 GDB now builds as a cross debugger hosted on i686-mingw32, including
2810 native console support, and remote communications using either
2811 network sockets or serial ports.
2813 * Improved Modula-2 language support
2815 GDB can now print most types in the Modula-2 syntax. This includes:
2816 basic types, set types, record types, enumerated types, range types,
2817 pointer types and ARRAY types. Procedure var parameters are correctly
2818 printed and hexadecimal addresses and character constants are also
2819 written in the Modula-2 syntax. Best results can be obtained by using
2820 GNU Modula-2 together with the -gdwarf-2 command line option.
2824 The ARM rdi-share module.
2826 The Netware NLM debug server.
2828 *** Changes in GDB 6.4
2830 * New native configurations
2832 OpenBSD/arm arm*-*-openbsd*
2833 OpenBSD/mips64 mips64-*-openbsd*
2837 Morpho Technologies ms1 ms1-elf
2839 * New command line options
2841 --batch-silent As for --batch, but totally silent.
2842 --return-child-result The debugger will exist with the same value
2843 the child (debugged) program exited with.
2844 --eval-command COMMAND, -ex COMMAND
2845 Execute a single GDB CLI command. This may be
2846 specified multiple times and in conjunction
2847 with the --command (-x) option.
2849 * Deprecated commands removed
2851 The following commands, that were deprecated in 2000, have been
2855 set|show arm disassembly-flavor set|show arm disassembler
2856 othernames set arm disassembler
2857 set|show remotedebug set|show debug remote
2858 set|show archdebug set|show debug arch
2859 set|show eventdebug set|show debug event
2862 * New BSD user-level threads support
2864 It is now possible to debug programs using the user-level threads
2865 library on OpenBSD and FreeBSD. Currently supported (target)
2868 FreeBSD/amd64 x86_64-*-freebsd*
2869 FreeBSD/i386 i386-*-freebsd*
2870 OpenBSD/i386 i386-*-openbsd*
2872 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2873 are not yet supported.
2875 * New support for Matsushita MN10300 w/sim added
2876 (Work in progress). mn10300-elf.
2878 * REMOVED configurations and files
2880 VxWorks and the XDR protocol *-*-vxworks
2881 Motorola MCORE mcore-*-*
2882 National Semiconductor NS32000 ns32k-*-*
2884 * New "set print array-indexes" command
2886 After turning this setting "on", GDB prints the index of each element
2887 when displaying arrays. The default is "off" to preserve the previous
2890 * VAX floating point support
2892 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2894 * User-defined command support
2896 In addition to using $arg0..$arg9 for argument passing, it is now possible
2897 to use $argc to determine now many arguments have been passed. See the
2898 section on user-defined commands in the user manual for more information.
2900 *** Changes in GDB 6.3:
2902 * New command line option
2904 GDB now accepts -l followed by a number to set the timeout for remote
2907 * GDB works with GCC -feliminate-dwarf2-dups
2909 GDB now supports a more compact representation of DWARF-2 debug
2910 information using DW_FORM_ref_addr references. These are produced
2911 by GCC with the option -feliminate-dwarf2-dups and also by some
2912 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2913 to use -feliminate-dwarf2-dups.
2915 * Internationalization
2917 When supported by the host system, GDB will be built with
2918 internationalization (libintl). The task of marking up the sources is
2919 continued, we're looking forward to our first translation.
2923 Initial support for debugging programs compiled with the GNAT
2924 implementation of the Ada programming language has been integrated
2925 into GDB. In this release, support is limited to expression evaluation.
2927 * New native configurations
2929 GNU/Linux/m32r m32r-*-linux-gnu
2933 GDB's remote protocol now includes support for the 'p' packet. This
2934 packet is used to fetch individual registers from a remote inferior.
2936 * END-OF-LIFE registers[] compatibility module
2938 GDB's internal register infrastructure has been completely rewritten.
2939 The new infrastructure making possible the implementation of key new
2940 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2943 GDB 6.3 will be the last release to include the the registers[]
2944 compatibility module that allowed out-of-date configurations to
2945 continue to work. This change directly impacts the following
2955 powerpc bdm protocol
2957 Unless there is activity to revive these configurations, they will be
2958 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2960 * OBSOLETE configurations and files
2962 Configurations that have been declared obsolete in this release have
2963 been commented out. Unless there is activity to revive these
2964 configurations, the next release of GDB will have their sources
2965 permanently REMOVED.
2974 *** Changes in GDB 6.2.1:
2976 * MIPS `break main; run' gave an heuristic-fence-post warning
2978 When attempting to run even a simple program, a warning about
2979 heuristic-fence-post being hit would be reported. This problem has
2982 * MIPS IRIX 'long double' crashed GDB
2984 When examining a long double variable, GDB would get a segmentation
2985 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2986 IRIX long double values).
2990 A bug in the VAX stack code was causing problems with the "next"
2991 command. This problem has been fixed.
2993 *** Changes in GDB 6.2:
2995 * Fix for ``many threads''
2997 On GNU/Linux systems that use the NPTL threads library, a program
2998 rapidly creating and deleting threads would confuse GDB leading to the
3001 ptrace: No such process.
3002 thread_db_get_info: cannot get thread info: generic error
3004 This problem has been fixed.
3006 * "-async" and "-noasync" options removed.
3008 Support for the broken "-noasync" option has been removed (it caused
3011 * New ``start'' command.
3013 This command runs the program until the begining of the main procedure.
3015 * New BSD Kernel Data Access Library (libkvm) interface
3017 Using ``target kvm'' it is now possible to debug kernel core dumps and
3018 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3019 platforms. Currently supported (native-only) configurations are:
3021 FreeBSD/amd64 x86_64-*-freebsd*
3022 FreeBSD/i386 i?86-*-freebsd*
3023 NetBSD/i386 i?86-*-netbsd*
3024 NetBSD/m68k m68*-*-netbsd*
3025 NetBSD/sparc sparc-*-netbsd*
3026 OpenBSD/amd64 x86_64-*-openbsd*
3027 OpenBSD/i386 i?86-*-openbsd*
3028 OpenBSD/m68k m68*-openbsd*
3029 OpenBSD/sparc sparc-*-openbsd*
3031 * Signal trampoline code overhauled
3033 Many generic problems with GDB's signal handling code have been fixed.
3034 These include: backtraces through non-contiguous stacks; recognition
3035 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3036 call; backtrace through a signal trampoline; step into and out of
3037 signal handlers; and single-stepping in the signal trampoline.
3039 Please note that kernel bugs are a limiting factor here. These
3040 features have been shown to work on an s390 GNU/Linux system that
3041 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3043 * Cygwin support for DWARF 2 added.
3045 * New native configurations
3047 GNU/Linux/hppa hppa*-*-linux*
3048 OpenBSD/hppa hppa*-*-openbsd*
3049 OpenBSD/m68k m68*-*-openbsd*
3050 OpenBSD/m88k m88*-*-openbsd*
3051 OpenBSD/powerpc powerpc-*-openbsd*
3052 NetBSD/vax vax-*-netbsd*
3053 OpenBSD/vax vax-*-openbsd*
3055 * END-OF-LIFE frame compatibility module
3057 GDB's internal frame infrastructure has been completely rewritten.
3058 The new infrastructure making it possible to support key new features
3059 including DWARF 2 Call Frame Information. To aid in the task of
3060 migrating old configurations to this new infrastructure, a
3061 compatibility module, that allowed old configurations to continue to
3062 work, was also included.
3064 GDB 6.2 will be the last release to include this frame compatibility
3065 module. This change directly impacts the following configurations:
3075 Unless there is activity to revive these configurations, they will be
3076 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3078 * REMOVED configurations and files
3080 Sun 3, running SunOS 3 m68*-*-sunos3*
3081 Sun 3, running SunOS 4 m68*-*-sunos4*
3082 Sun 2, running SunOS 3 m68000-*-sunos3*
3083 Sun 2, running SunOS 4 m68000-*-sunos4*
3084 Motorola 680x0 running LynxOS m68*-*-lynxos*
3085 AT&T 3b1/Unix pc m68*-att-*
3086 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3087 decstation mips-dec-* mips-little-*
3088 riscos mips-*-riscos* mips-*-sysv*
3089 sonymips mips-sony-*
3090 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3092 *** Changes in GDB 6.1.1:
3094 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3096 The TUI (Text-mode User Interface) is now built as part of a default
3097 GDB configuration. It is enabled by either selecting the TUI with the
3098 command line option "-i=tui" or by running the separate "gdbtui"
3099 program. For more information on the TUI, see the manual "Debugging
3102 * Pending breakpoint support (also included in GDB 6.1)
3104 Support has been added to allow you to specify breakpoints in shared
3105 libraries that have not yet been loaded. If a breakpoint location
3106 cannot be found, and the "breakpoint pending" option is set to auto,
3107 GDB queries you if you wish to make the breakpoint pending on a future
3108 shared-library load. If and when GDB resolves the breakpoint symbol,
3109 the pending breakpoint is removed as one or more regular breakpoints
3112 Pending breakpoints are very useful for GCJ Java debugging.
3114 * Fixed ISO-C build problems
3116 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3117 non ISO-C code that stopped them being built using a more strict ISO-C
3118 compiler (e.g., IBM's C compiler).
3120 * Fixed build problem on IRIX 5
3122 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3123 wasn't able to compile compile on an IRIX 5 system.
3125 * Added execute permission to gdb/gdbserver/configure
3127 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3128 permission. This bug would cause configure to fail on a number of
3129 systems (Solaris, IRIX). Ref: server/519.
3131 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3133 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3134 has been updated to use constant array sizes.
3136 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3138 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3139 its generated DWARF Call Frame Info. This encoding was causing GDB to
3140 panic, that panic has been fixed. Ref: gdb/1628.
3142 * Fixed a problem when examining parameters in shared library code.
3144 When examining parameters in optimized shared library code generated
3145 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3146 not available''. GDB now correctly displays the variable's value.
3148 *** Changes in GDB 6.1:
3150 * Removed --with-mmalloc
3152 Support for the mmalloc memory manager has been removed, as it
3153 conflicted with the internal gdb byte cache.
3155 * Changes in AMD64 configurations
3157 The AMD64 target now includes the %cs and %ss registers. As a result
3158 the AMD64 remote protocol has changed; this affects the floating-point
3159 and SSE registers. If you rely on those registers for your debugging,
3160 you should upgrade gdbserver on the remote side.
3162 * Revised SPARC target
3164 The SPARC target has been completely revised, incorporating the
3165 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3166 support for LynxOS and SunOS 4 has been dropped. Calling functions
3167 from within GDB on operating systems with a non-executable stack
3168 (Solaris, OpenBSD) now works.
3172 GDB has a new C++ demangler which does a better job on the mangled
3173 names generated by current versions of g++. It also runs faster, so
3174 with this and other changes gdb should now start faster on large C++
3177 * DWARF 2 Location Expressions
3179 GDB support for location expressions has been extended to support function
3180 arguments and frame bases. Older versions of GDB could crash when they
3183 * C++ nested types and namespaces
3185 GDB's support for nested types and namespaces in C++ has been
3186 improved, especially if you use the DWARF 2 debugging format. (This
3187 is the default for recent versions of GCC on most platforms.)
3188 Specifically, if you have a class "Inner" defined within a class or
3189 namespace "Outer", then GDB realizes that the class's name is
3190 "Outer::Inner", not simply "Inner". This should greatly reduce the
3191 frequency of complaints about not finding RTTI symbols. In addition,
3192 if you are stopped at inside of a function defined within a namespace,
3193 GDB modifies its name lookup accordingly.
3195 * New native configurations
3197 NetBSD/amd64 x86_64-*-netbsd*
3198 OpenBSD/amd64 x86_64-*-openbsd*
3199 OpenBSD/alpha alpha*-*-openbsd*
3200 OpenBSD/sparc sparc-*-openbsd*
3201 OpenBSD/sparc64 sparc64-*-openbsd*
3203 * New debugging protocols
3205 M32R with SDI protocol m32r-*-elf*
3207 * "set prompt-escape-char" command deleted.
3209 The command "set prompt-escape-char" has been deleted. This command,
3210 and its very obscure effet on GDB's prompt, was never documented,
3211 tested, nor mentioned in the NEWS file.
3213 * OBSOLETE configurations and files
3215 Configurations that have been declared obsolete in this release have
3216 been commented out. Unless there is activity to revive these
3217 configurations, the next release of GDB will have their sources
3218 permanently REMOVED.
3220 Sun 3, running SunOS 3 m68*-*-sunos3*
3221 Sun 3, running SunOS 4 m68*-*-sunos4*
3222 Sun 2, running SunOS 3 m68000-*-sunos3*
3223 Sun 2, running SunOS 4 m68000-*-sunos4*
3224 Motorola 680x0 running LynxOS m68*-*-lynxos*
3225 AT&T 3b1/Unix pc m68*-att-*
3226 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3227 decstation mips-dec-* mips-little-*
3228 riscos mips-*-riscos* mips-*-sysv*
3229 sonymips mips-sony-*
3230 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3232 * REMOVED configurations and files
3234 SGI Irix-4.x mips-sgi-irix4 or iris4
3235 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3236 Z8000 simulator z8k-zilog-none or z8ksim
3237 Matsushita MN10200 w/simulator mn10200-*-*
3238 H8/500 simulator h8500-hitachi-hms or h8500hms
3239 HP/PA running BSD hppa*-*-bsd*
3240 HP/PA running OSF/1 hppa*-*-osf*
3241 HP/PA Pro target hppa*-*-pro*
3242 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3243 386BSD i[3456]86-*-bsd*
3244 Sequent family i[3456]86-sequent-sysv4*
3245 i[3456]86-sequent-sysv*
3246 i[3456]86-sequent-bsd*
3247 SPARC running LynxOS sparc-*-lynxos*
3248 SPARC running SunOS 4 sparc-*-sunos4*
3249 Tsqware Sparclet sparclet-*-*
3250 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3252 *** Changes in GDB 6.0:
3256 Support for debugging the Objective-C programming language has been
3257 integrated into GDB.
3259 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3261 DWARF 2's Call Frame Information makes available compiler generated
3262 information that more exactly describes the program's run-time stack.
3263 By using this information, GDB is able to provide more robust stack
3266 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3267 have been updated to use a new backtrace mechanism which includes
3268 DWARF 2 CFI support.
3272 GDB's remote protocol has been extended to include support for hosted
3273 file I/O (where the remote target uses GDB's file system). See GDB's
3274 remote protocol documentation for details.
3276 * All targets using the new architecture framework.
3278 All of GDB's targets have been updated to use the new internal
3279 architecture framework. The way is now open for future GDB releases
3280 to include cross-architecture native debugging support (i386 on amd64,
3283 * GNU/Linux's Thread Local Storage (TLS)
3285 GDB now includes support for for the GNU/Linux implementation of
3286 per-thread variables.
3288 * GNU/Linux's Native POSIX Thread Library (NPTL)
3290 GDB's thread code has been updated to work with either the new
3291 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3293 * Separate debug info.
3295 GDB, in conjunction with BINUTILS, now supports a mechanism for
3296 automatically loading debug information from a separate file. Instead
3297 of shipping full debug and non-debug versions of system libraries,
3298 system integrators can now instead ship just the stripped libraries
3299 and optional debug files.
3301 * DWARF 2 Location Expressions
3303 DWARF 2 Location Expressions allow the compiler to more completely
3304 describe the location of variables (even in optimized code) to the
3307 GDB now includes preliminary support for location expressions (support
3308 for DW_OP_piece is still missing).
3312 A number of long standing bugs that caused GDB to die while starting a
3313 Java application have been fixed. GDB's Java support is now
3314 considered "useable".
3316 * GNU/Linux support for fork, vfork, and exec.
3318 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3319 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3322 * GDB supports logging output to a file
3324 There are two new commands, "set logging" and "show logging", which can be
3325 used to capture GDB's output to a file.
3327 * The meaning of "detach" has changed for gdbserver
3329 The "detach" command will now resume the application, as documented. To
3330 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3333 * d10v, m68hc11 `regs' command deprecated
3335 The `info registers' command has been updated so that it displays the
3336 registers using a format identical to the old `regs' command.
3340 A new command, "maint set profile on/off", has been added. This command can
3341 be used to enable or disable profiling while running GDB, to profile a
3342 session or a set of commands. In addition there is a new configure switch,
3343 "--enable-profiling", which will cause GDB to be compiled with profiling
3344 data, for more informative profiling results.
3346 * Default MI syntax changed to "mi2".
3348 The default MI (machine interface) syntax, enabled by the command line
3349 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3350 "mi1", can be enabled by specifying the option "-i=mi1".
3352 Support for the original "mi0" syntax (included in GDB 5.0) has been
3355 Fix for gdb/192: removed extraneous space when displaying frame level.
3356 Fix for gdb/672: update changelist is now output in mi list format.
3357 Fix for gdb/702: a -var-assign that updates the value now shows up
3358 in a subsequent -var-update.
3360 * New native configurations.
3362 FreeBSD/amd64 x86_64-*-freebsd*
3364 * Multi-arched targets.
3366 HP/PA HPUX11 hppa*-*-hpux*
3367 Renesas M32R/D w/simulator m32r-*-elf*
3369 * OBSOLETE configurations and files
3371 Configurations that have been declared obsolete in this release have
3372 been commented out. Unless there is activity to revive these
3373 configurations, the next release of GDB will have their sources
3374 permanently REMOVED.
3376 Z8000 simulator z8k-zilog-none or z8ksim
3377 Matsushita MN10200 w/simulator mn10200-*-*
3378 H8/500 simulator h8500-hitachi-hms or h8500hms
3379 HP/PA running BSD hppa*-*-bsd*
3380 HP/PA running OSF/1 hppa*-*-osf*
3381 HP/PA Pro target hppa*-*-pro*
3382 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3383 Sequent family i[3456]86-sequent-sysv4*
3384 i[3456]86-sequent-sysv*
3385 i[3456]86-sequent-bsd*
3386 Tsqware Sparclet sparclet-*-*
3387 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3389 * REMOVED configurations and files
3392 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3393 IBM AIX PS/2 i[3456]86-*-aix
3394 i386 running Mach 3.0 i[3456]86-*-mach3*
3395 i386 running Mach i[3456]86-*-mach*
3396 i386 running OSF/1 i[3456]86-*osf1mk*
3397 HP/Apollo 68k Family m68*-apollo*-sysv*,
3399 m68*-hp-bsd*, m68*-hp-hpux*
3400 Argonaut Risc Chip (ARC) arc-*-*
3401 Mitsubishi D30V d30v-*-*
3402 Fujitsu FR30 fr30-*-elf*
3403 OS/9000 i[34]86-*-os9k
3404 I960 with MON960 i960-*-coff
3406 * MIPS $fp behavior changed
3408 The convenience variable $fp, for the MIPS, now consistently returns
3409 the address of the current frame's base. Previously, depending on the
3410 context, $fp could refer to either $sp or the current frame's base
3411 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3412 The GNU Source-Level Debugger''.
3414 *** Changes in GDB 5.3:
3416 * GNU/Linux shared library multi-threaded performance improved.
3418 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3419 `/proc', in preference to `ptrace' for memory reads. This may result
3420 in an improvement in the start-up time of multi-threaded, shared
3421 library applications when run under GDB. One GDB user writes: ``loads
3422 shared libs like mad''.
3424 * ``gdbserver'' now supports multi-threaded applications on some targets
3426 Support for debugging multi-threaded applications which use
3427 the GNU/Linux LinuxThreads package has been added for
3428 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3429 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3431 * GDB now supports C/C++ preprocessor macros.
3433 GDB now expands preprocessor macro invocations in C/C++ expressions,
3434 and provides various commands for showing macro definitions and how
3437 The new command `macro expand EXPRESSION' expands any macro
3438 invocations in expression, and shows the result.
3440 The new command `show macro MACRO-NAME' shows the definition of the
3441 macro named MACRO-NAME, and where it was defined.
3443 Most compilers don't include information about macros in the debugging
3444 information by default. In GCC 3.1, for example, you need to compile
3445 your program with the options `-gdwarf-2 -g3'. If the macro
3446 information is present in the executable, GDB will read it.
3448 * Multi-arched targets.
3450 DEC Alpha (partial) alpha*-*-*
3451 DEC VAX (partial) vax-*-*
3453 National Semiconductor NS32000 (partial) ns32k-*-*
3454 Motorola 68000 (partial) m68k-*-*
3455 Motorola MCORE mcore-*-*
3459 Fujitsu FRV architecture added by Red Hat frv*-*-*
3462 * New native configurations
3464 Alpha NetBSD alpha*-*-netbsd*
3465 SH NetBSD sh*-*-netbsdelf*
3466 MIPS NetBSD mips*-*-netbsd*
3467 UltraSPARC NetBSD sparc64-*-netbsd*
3469 * OBSOLETE configurations and files
3471 Configurations that have been declared obsolete in this release have
3472 been commented out. Unless there is activity to revive these
3473 configurations, the next release of GDB will have their sources
3474 permanently REMOVED.
3476 Mitsubishi D30V d30v-*-*
3477 OS/9000 i[34]86-*-os9k
3478 IBM AIX PS/2 i[3456]86-*-aix
3479 Fujitsu FR30 fr30-*-elf*
3480 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3481 Argonaut Risc Chip (ARC) arc-*-*
3482 i386 running Mach 3.0 i[3456]86-*-mach3*
3483 i386 running Mach i[3456]86-*-mach*
3484 i386 running OSF/1 i[3456]86-*osf1mk*
3485 HP/Apollo 68k Family m68*-apollo*-sysv*,
3487 m68*-hp-bsd*, m68*-hp-hpux*
3488 I960 with MON960 i960-*-coff
3490 * OBSOLETE languages
3492 CHILL, a Pascal like language used by telecommunications companies.
3494 * REMOVED configurations and files
3496 AMD 29k family via UDI a29k-amd-udi, udi29k
3497 A29K VxWorks a29k-*-vxworks
3498 AMD 29000 embedded, using EBMON a29k-none-none
3499 AMD 29000 embedded with COFF a29k-none-coff
3500 AMD 29000 embedded with a.out a29k-none-aout
3502 testsuite/gdb.hp/gdb.threads-hp/ directory
3504 * New command "set max-user-call-depth <nnn>"
3506 This command allows the user to limit the call depth of user-defined
3507 commands. The default is 1024.
3509 * Changes in FreeBSD/i386 native debugging.
3511 Support for the "generate-core-file" has been added.
3513 * New commands "dump", "append", and "restore".
3515 These commands allow data to be copied from target memory
3516 to a bfd-format or binary file (dump and append), and back
3517 from a file into memory (restore).
3519 * Improved "next/step" support on multi-processor Alpha Tru64.
3521 The previous single-step mechanism could cause unpredictable problems,
3522 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3523 of a software single-step mechanism prevents this.
3525 *** Changes in GDB 5.2.1:
3533 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3534 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3535 Fix, by Joel Brobecker imported from mainline.
3537 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3538 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3539 Fix, by Fred Fish, imported from mainline.
3541 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3542 Surprisingly enough, it works now.
3543 By Michal Ludvig, imported from mainline.
3545 i386 hardware watchpoint support:
3546 avoid misses on second run for some targets.
3547 By Pierre Muller, imported from mainline.
3549 *** Changes in GDB 5.2:
3551 * New command "set trust-readonly-sections on[off]".
3553 This command is a hint that tells gdb that read-only sections
3554 really are read-only (ie. that their contents will not change).
3555 In this mode, gdb will go to the object file rather than the
3556 target to read memory from read-only sections (such as ".text").
3557 This can be a significant performance improvement on some
3558 (notably embedded) targets.
3560 * New command "generate-core-file" (or "gcore").
3562 This new gdb command allows the user to drop a core file of the child
3563 process state at any time. So far it's been implemented only for
3564 GNU/Linux and Solaris, but should be relatively easily ported to other
3565 hosts. Argument is core file name (defaults to core.<pid>).
3567 * New command line option
3569 GDB now accepts --pid or -p followed by a process id.
3571 * Change in command line behavior -- corefiles vs. process ids.
3573 There is a subtle behavior in the way in which GDB handles
3574 command line arguments. The first non-flag argument is always
3575 a program to debug, but the second non-flag argument may either
3576 be a corefile or a process id. Previously, GDB would attempt to
3577 open the second argument as a corefile, and if that failed, would
3578 issue a superfluous error message and then attempt to attach it as
3579 a process. Now, if the second argument begins with a non-digit,
3580 it will be treated as a corefile. If it begins with a digit,
3581 GDB will attempt to attach it as a process, and if no such process
3582 is found, will then attempt to open it as a corefile.
3584 * Changes in ARM configurations.
3586 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3587 configuration is fully multi-arch.
3589 * New native configurations
3591 ARM NetBSD arm*-*-netbsd*
3592 x86 OpenBSD i[3456]86-*-openbsd*
3593 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3594 Sparc64 running FreeBSD sparc64-*-freebsd*
3598 Sanyo XStormy16 xstormy16-elf
3600 * OBSOLETE configurations and files
3602 Configurations that have been declared obsolete in this release have
3603 been commented out. Unless there is activity to revive these
3604 configurations, the next release of GDB will have their sources
3605 permanently REMOVED.
3607 AMD 29k family via UDI a29k-amd-udi, udi29k
3608 A29K VxWorks a29k-*-vxworks
3609 AMD 29000 embedded, using EBMON a29k-none-none
3610 AMD 29000 embedded with COFF a29k-none-coff
3611 AMD 29000 embedded with a.out a29k-none-aout
3613 testsuite/gdb.hp/gdb.threads-hp/ directory
3615 * REMOVED configurations and files
3617 TI TMS320C80 tic80-*-*
3619 PowerPC Solaris powerpcle-*-solaris*
3620 PowerPC Windows NT powerpcle-*-cygwin32
3621 PowerPC Netware powerpc-*-netware*
3622 Harris/CXUX m88k m88*-harris-cxux*
3623 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3624 ns32k-utek-sysv* ns32k-utek-*
3625 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3626 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3627 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3628 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3629 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3631 * Changes to command line processing
3633 The new `--args' feature can be used to specify command-line arguments
3634 for the inferior from gdb's command line.
3636 * Changes to key bindings
3638 There is a new `operate-and-get-next' function bound to `C-o'.
3640 *** Changes in GDB 5.1.1
3642 Fix compile problem on DJGPP.
3644 Fix a problem with floating-point registers on the i386 being
3647 Fix to stop GDB crashing on .debug_str debug info.
3649 Numerous documentation fixes.
3651 Numerous testsuite fixes.
3653 *** Changes in GDB 5.1:
3655 * New native configurations
3657 Alpha FreeBSD alpha*-*-freebsd*
3658 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3659 MIPS GNU/Linux mips*-*-linux*
3660 MIPS SGI Irix 6.x mips*-sgi-irix6*
3661 ia64 AIX ia64-*-aix*
3662 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3666 Motorola 68HC11 and 68HC12 m68hc11-elf
3668 UltraSparc running GNU/Linux sparc64-*-linux*
3670 * OBSOLETE configurations and files
3672 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3673 Harris/CXUX m88k m88*-harris-cxux*
3674 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3675 ns32k-utek-sysv* ns32k-utek-*
3676 TI TMS320C80 tic80-*-*
3678 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3679 PowerPC Solaris powerpcle-*-solaris*
3680 PowerPC Windows NT powerpcle-*-cygwin32
3681 PowerPC Netware powerpc-*-netware*
3682 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3683 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3684 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3685 Apple Macintosh (MPW) host N/A
3687 stuff.c (Program to stuff files into a specially prepared space in kdb)
3688 kdb-start.c (Main loop for the standalone kernel debugger)
3690 Configurations that have been declared obsolete in this release have
3691 been commented out. Unless there is activity to revive these
3692 configurations, the next release of GDB will have their sources
3693 permanently REMOVED.
3695 * REMOVED configurations and files
3697 Altos 3068 m68*-altos-*
3698 Convex c1-*-*, c2-*-*
3700 ARM RISCix arm-*-* (as host)
3704 * GDB has been converted to ISO C.
3706 GDB's source code has been converted to ISO C. In particular, the
3707 sources are fully protoized, and rely on standard headers being
3712 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3714 * The MI enabled by default.
3716 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3717 revised and enabled by default. Packages which use GDB as a debugging
3718 engine behind a UI or another front end are encouraged to switch to
3719 using the GDB/MI interface, instead of the old annotations interface
3720 which is now deprecated.
3722 * Support for debugging Pascal programs.
3724 GDB now includes support for debugging Pascal programs. The following
3725 main features are supported:
3727 - Pascal-specific data types such as sets;
3729 - automatic recognition of Pascal sources based on file-name
3732 - Pascal-style display of data types, variables, and functions;
3734 - a Pascal expression parser.
3736 However, some important features are not yet supported.
3738 - Pascal string operations are not supported at all;
3740 - there are some problems with boolean types;
3742 - Pascal type hexadecimal constants are not supported
3743 because they conflict with the internal variables format;
3745 - support for Pascal objects and classes is not full yet;
3747 - unlike Pascal, GDB is case-sensitive for symbol names.
3749 * Changes in completion.
3751 Commands such as `shell', `run' and `set args', which pass arguments
3752 to inferior programs, now complete on file names, similar to what
3753 users expect at the shell prompt.
3755 Commands which accept locations, such as `disassemble', `print',
3756 `breakpoint', `until', etc. now complete on filenames as well as
3757 program symbols. Thus, if you type "break foob TAB", and the source
3758 files linked into the programs include `foobar.c', that file name will
3759 be one of the candidates for completion. However, file names are not
3760 considered for completion after you typed a colon that delimits a file
3761 name from a name of a function in that file, as in "break foo.c:bar".
3763 `set demangle-style' completes on available demangling styles.
3765 * New platform-independent commands:
3767 It is now possible to define a post-hook for a command as well as a
3768 hook that runs before the command. For more details, see the
3769 documentation of `hookpost' in the GDB manual.
3771 * Changes in GNU/Linux native debugging.
3773 Support for debugging multi-threaded programs has been completely
3774 revised for all platforms except m68k and sparc. You can now debug as
3775 many threads as your system allows you to have.
3777 Attach/detach is supported for multi-threaded programs.
3779 Support for SSE registers was added for x86. This doesn't work for
3780 multi-threaded programs though.
3782 * Changes in MIPS configurations.
3784 Multi-arch support is enabled for all MIPS configurations.
3786 GDB can now be built as native debugger on SGI Irix 6.x systems for
3787 debugging n32 executables. (Debugging 64-bit executables is not yet
3790 * Unified support for hardware watchpoints in all x86 configurations.
3792 Most (if not all) native x86 configurations support hardware-assisted
3793 breakpoints and watchpoints in a unified manner. This support
3794 implements debug register sharing between watchpoints, which allows to
3795 put a virtually infinite number of watchpoints on the same address,
3796 and also supports watching regions up to 16 bytes with several debug
3799 The new maintenance command `maintenance show-debug-regs' toggles
3800 debugging print-outs in functions that insert, remove, and test
3801 watchpoints and hardware breakpoints.
3803 * Changes in the DJGPP native configuration.
3805 New command ``info dos sysinfo'' displays assorted information about
3806 the CPU, OS, memory, and DPMI server.
3808 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3809 display information about segment descriptors stored in GDT, LDT, and
3812 New commands ``info dos pde'' and ``info dos pte'' display entries
3813 from Page Directory and Page Tables (for now works with CWSDPMI only).
3814 New command ``info dos address-pte'' displays the Page Table entry for
3815 a given linear address.
3817 GDB can now pass command lines longer than 126 characters to the
3818 program being debugged (requires an update to the libdbg.a library
3819 which is part of the DJGPP development kit).
3821 DWARF2 debug info is now supported.
3823 It is now possible to `step' and `next' through calls to `longjmp'.
3825 * Changes in documentation.
3827 All GDB documentation was converted to GFDL, the GNU Free
3828 Documentation License.
3830 Tracepoints-related commands are now fully documented in the GDB
3833 TUI, the Text-mode User Interface, is now documented in the manual.
3835 Tracepoints-related commands are now fully documented in the GDB
3838 The "GDB Internals" manual now has an index. It also includes
3839 documentation of `ui_out' functions, GDB coding standards, x86
3840 hardware watchpoints, and memory region attributes.
3842 * GDB's version number moved to ``version.in''
3844 The Makefile variable VERSION has been replaced by the file
3845 ``version.in''. People creating GDB distributions should update the
3846 contents of this file.
3850 GUD support is now a standard part of the EMACS distribution.
3852 *** Changes in GDB 5.0:
3854 * Improved support for debugging FP programs on x86 targets
3856 Unified and much-improved support for debugging floating-point
3857 programs on all x86 targets. In particular, ``info float'' now
3858 displays the FP registers in the same format on all x86 targets, with
3859 greater level of detail.
3861 * Improvements and bugfixes in hardware-assisted watchpoints
3863 It is now possible to watch array elements, struct members, and
3864 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3865 on x86 targets no longer erroneously trigger when the address is
3868 * Improvements in the native DJGPP version of GDB
3870 The distribution now includes all the scripts and auxiliary files
3871 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3872 machines ``out of the box''.
3874 The DJGPP version can now debug programs that use signals. It is
3875 possible to catch signals that happened in the debuggee, deliver
3876 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3877 would kill the program being debugged.) Programs that hook hardware
3878 interrupts (keyboard, timer, etc.) can also be debugged.
3880 It is now possible to debug DJGPP programs that redirect their
3881 standard handles or switch them to raw (as opposed to cooked) mode, or
3882 even close them. The command ``run < foo > bar'' works as expected,
3883 and ``info terminal'' reports useful information about the debuggee's
3884 terminal, including raw/cooked mode, redirection, etc.
3886 The DJGPP version now uses termios functions for console I/O, which
3887 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3890 DOS-style file names with drive letters are now fully supported by
3893 It is now possible to debug DJGPP programs that switch their working
3894 directory. It is also possible to rerun the debuggee any number of
3895 times without restarting GDB; thus, you can use the same setup,
3896 breakpoints, etc. for many debugging sessions.
3898 * New native configurations
3900 ARM GNU/Linux arm*-*-linux*
3901 PowerPC GNU/Linux powerpc-*-linux*
3905 Motorola MCore mcore-*-*
3906 x86 VxWorks i[3456]86-*-vxworks*
3907 PowerPC VxWorks powerpc-*-vxworks*
3908 TI TMS320C80 tic80-*-*
3910 * OBSOLETE configurations
3912 Altos 3068 m68*-altos-*
3913 Convex c1-*-*, c2-*-*
3915 ARM RISCix arm-*-* (as host)
3918 Configurations that have been declared obsolete will be commented out,
3919 but the code will be left in place. If there is no activity to revive
3920 these configurations before the next release of GDB, the sources will
3921 be permanently REMOVED.
3923 * Gould support removed
3925 Support for the Gould PowerNode and NP1 has been removed.
3927 * New features for SVR4
3929 On SVR4 native platforms (such as Solaris), if you attach to a process
3930 without first loading a symbol file, GDB will now attempt to locate and
3931 load symbols from the running process's executable file.
3933 * Many C++ enhancements
3935 C++ support has been greatly improved. Overload resolution now works properly
3936 in almost all cases. RTTI support is on the way.
3938 * Remote targets can connect to a sub-program
3940 A popen(3) style serial-device has been added. This device starts a
3941 sub-process (such as a stand-alone simulator) and then communicates
3942 with that. The sub-program to run is specified using the syntax
3943 ``|<program> <args>'' vis:
3945 (gdb) set remotedebug 1
3946 (gdb) target extended-remote |mn10300-elf-sim program-args
3948 * MIPS 64 remote protocol
3950 A long standing bug in the mips64 remote protocol where by GDB
3951 expected certain 32 bit registers (ex SR) to be transfered as 32
3952 instead of 64 bits has been fixed.
3954 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3955 added to provide backward compatibility with older versions of GDB.
3957 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3959 The command ``set remotebinarydownload'' command has been replaced by
3960 ``set remote X-packet''. Other commands in ``set remote'' family
3961 include ``set remote P-packet''.
3963 * Breakpoint commands accept ranges.
3965 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3966 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3967 ``tracepoint passcount'' also accepts a range of tracepoints.
3969 * ``apropos'' command added.
3971 The ``apropos'' command searches through command names and
3972 documentation strings, printing out matches, making it much easier to
3973 try to find a command that does what you are looking for.
3977 A new machine oriented interface (MI) has been added to GDB. This
3978 interface is designed for debug environments running GDB as a separate
3979 process. This is part of the long term libGDB project. See the
3980 "GDB/MI" chapter of the GDB manual for further information. It can be
3981 enabled by configuring with:
3983 .../configure --enable-gdbmi
3985 *** Changes in GDB-4.18:
3987 * New native configurations
3989 HP-UX 10.20 hppa*-*-hpux10.20
3990 HP-UX 11.x hppa*-*-hpux11.0*
3991 M68K GNU/Linux m68*-*-linux*
3995 Fujitsu FR30 fr30-*-elf*
3996 Intel StrongARM strongarm-*-*
3997 Mitsubishi D30V d30v-*-*
3999 * OBSOLETE configurations
4001 Gould PowerNode, NP1 np1-*-*, pn-*-*
4003 Configurations that have been declared obsolete will be commented out,
4004 but the code will be left in place. If there is no activity to revive
4005 these configurations before the next release of GDB, the sources will
4006 be permanently REMOVED.
4010 As a compatibility experiment, GDB's source files buildsym.h and
4011 buildsym.c have been converted to pure standard C, no longer
4012 containing any K&R compatibility code. We believe that all systems in
4013 use today either come with a standard C compiler, or have a GCC port
4014 available. If this is not true, please report the affected
4015 configuration to bug-gdb@gnu.org immediately. See the README file for
4016 information about getting a standard C compiler if you don't have one
4021 GDB now uses readline 2.2.
4023 * set extension-language
4025 You can now control the mapping between filename extensions and source
4026 languages by using the `set extension-language' command. For instance,
4027 you can ask GDB to treat .c files as C++ by saying
4028 set extension-language .c c++
4029 The command `info extensions' lists all of the recognized extensions
4030 and their associated languages.
4032 * Setting processor type for PowerPC and RS/6000
4034 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4035 you can use the `set processor' command to specify what variant of the
4036 PowerPC family you are debugging. The command
4040 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4041 following PowerPC and RS6000 variants:
4043 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4044 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4046 403GC IBM PowerPC 403GC
4047 505 Motorola PowerPC 505
4048 860 Motorola PowerPC 860 or 850
4049 601 Motorola PowerPC 601
4050 602 Motorola PowerPC 602
4051 603 Motorola/IBM PowerPC 603 or 603e
4052 604 Motorola PowerPC 604 or 604e
4053 750 Motorola/IBM PowerPC 750 or 750
4055 At the moment, this command just tells GDB what to name the
4056 special-purpose processor registers. Since almost all the affected
4057 registers are inaccessible to user-level programs, this command is
4058 only useful for remote debugging in its present form.
4062 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4063 more extensive support for HP-UX. Added features include shared
4064 library support, kernel threads and hardware watchpoints for 11.00,
4065 support for HP's ANSI C and C++ compilers, and a compatibility mode
4066 for xdb and dbx commands.
4070 HP's donation includes the new concept of catchpoints, which is a
4071 generalization of the old catch command. On HP-UX, it is now possible
4072 to catch exec, fork, and vfork, as well as library loading.
4074 This means that the existing catch command has changed; its first
4075 argument now specifies the type of catch to be set up. See the
4076 output of "help catch" for a list of catchpoint types.
4078 * Debugging across forks
4080 On HP-UX, you can choose which process to debug when a fork() happens
4085 HP has donated a curses-based terminal user interface (TUI). To get
4086 it, build with --enable-tui. Although this can be enabled for any
4087 configuration, at present it only works for native HP debugging.
4089 * GDB remote protocol additions
4091 A new protocol packet 'X' that writes binary data is now available.
4092 Default behavior is to try 'X', then drop back to 'M' if the stub
4093 fails to respond. The settable variable `remotebinarydownload'
4094 allows explicit control over the use of 'X'.
4096 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4097 full 64-bit address. The command
4099 set remoteaddresssize 32
4101 can be used to revert to the old behaviour. For existing remote stubs
4102 the change should not be noticed, as the additional address information
4105 In order to assist in debugging stubs, you may use the maintenance
4106 command `packet' to send any text string to the stub. For instance,
4108 maint packet heythere
4110 sends the packet "$heythere#<checksum>". Note that it is very easy to
4111 disrupt a debugging session by sending the wrong packet at the wrong
4114 The compare-sections command allows you to compare section data on the
4115 target to what is in the executable file without uploading or
4116 downloading, by comparing CRC checksums.
4118 * Tracing can collect general expressions
4120 You may now collect general expressions at tracepoints. This requires
4121 further additions to the target-side stub; see tracepoint.c and
4122 doc/agentexpr.texi for further details.
4124 * mask-address variable for Mips
4126 For Mips targets, you may control the zeroing of the upper 32 bits of
4127 a 64-bit address by entering `set mask-address on'. This is mainly
4128 of interest to users of embedded R4xxx and R5xxx processors.
4130 * Higher serial baud rates
4132 GDB's serial code now allows you to specify baud rates 57600, 115200,
4133 230400, and 460800 baud. (Note that your host system may not be able
4134 to achieve all of these rates.)
4138 The i960 configuration now includes an initial implementation of a
4139 builtin simulator, contributed by Jim Wilson.
4142 *** Changes in GDB-4.17:
4144 * New native configurations
4146 Alpha GNU/Linux alpha*-*-linux*
4147 Unixware 2.x i[3456]86-unixware2*
4148 Irix 6.x mips*-sgi-irix6*
4149 PowerPC GNU/Linux powerpc-*-linux*
4150 PowerPC Solaris powerpcle-*-solaris*
4151 Sparc GNU/Linux sparc-*-linux*
4152 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4156 Argonaut Risc Chip (ARC) arc-*-*
4157 Hitachi H8/300S h8300*-*-*
4158 Matsushita MN10200 w/simulator mn10200-*-*
4159 Matsushita MN10300 w/simulator mn10300-*-*
4160 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4161 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4162 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4163 Mitsubishi D10V w/simulator d10v-*-*
4164 Mitsubishi M32R/D w/simulator m32r-*-elf*
4165 Tsqware Sparclet sparclet-*-*
4166 NEC V850 w/simulator v850-*-*
4168 * New debugging protocols
4170 ARM with RDI protocol arm*-*-*
4171 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4172 DDB and LSI variants of PMON protocol mips*-*-*
4173 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4174 PowerPC with SDS protocol powerpc{,le}-*-eabi
4175 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4179 All configurations can now understand and use the DWARF 2 debugging
4180 format. The choice is automatic, if the symbol file contains DWARF 2
4185 GDB now includes basic Java language support. This support is
4186 only useful with Java compilers that produce native machine code.
4188 * solib-absolute-prefix and solib-search-path
4190 For SunOS and SVR4 shared libraries, you may now set the prefix for
4191 loading absolute shared library symbol files, and the search path for
4192 locating non-absolute shared library symbol files.
4194 * Live range splitting
4196 GDB can now effectively debug code for which GCC has performed live
4197 range splitting as part of its optimization. See gdb/doc/LRS for
4198 more details on the expected format of the stabs information.
4202 GDB's support for the GNU Hurd, including thread debugging, has been
4203 updated to work with current versions of the Hurd.
4207 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4208 instruction set. ARM GDB automatically detects when Thumb
4209 instructions are in use, and adjusts disassembly and backtracing
4214 GDB's MIPS target configurations now handle the MIP16 16-bit
4219 GDB now includes support for overlays; if an executable has been
4220 linked such that multiple sections are based at the same address, GDB
4221 will decide which section to use for symbolic info. You can choose to
4222 control the decision manually, using overlay commands, or implement
4223 additional target-side support and use "overlay load-target" to bring
4224 in the overlay mapping. Do "help overlay" for more detail.
4228 The command "info symbol <address>" displays information about
4229 the symbol at the specified address.
4233 The standard remote protocol now includes an extension that allows
4234 asynchronous collection and display of trace data. This requires
4235 extensive support in the target-side debugging stub. Tracing mode
4236 includes a new interaction mode in GDB and new commands: see the
4237 file tracepoint.c for more details.
4241 Configurations for embedded MIPS now include a simulator contributed
4242 by Cygnus Solutions. The simulator supports the instruction sets
4243 of most MIPS variants.
4247 Sparc configurations may now include the ERC32 simulator contributed
4248 by the European Space Agency. The simulator is not built into
4249 Sparc targets by default; configure with --enable-sim to include it.
4253 For target configurations that may include multiple variants of a
4254 basic architecture (such as MIPS and SH), you may now set the
4255 architecture explicitly. "set arch" sets, "info arch" lists
4256 the possible architectures.
4258 *** Changes in GDB-4.16:
4260 * New native configurations
4262 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4263 M68K NetBSD m68k-*-netbsd*
4264 PowerPC AIX 4.x powerpc-*-aix*
4265 PowerPC MacOS powerpc-*-macos*
4266 PowerPC Windows NT powerpcle-*-cygwin32
4267 RS/6000 AIX 4.x rs6000-*-aix4*
4271 ARM with RDP protocol arm-*-*
4272 I960 with MON960 i960-*-coff
4273 MIPS VxWorks mips*-*-vxworks*
4274 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4275 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4277 Matra Sparclet sparclet-*-*
4281 The powerpc-eabi configuration now includes the PSIM simulator,
4282 contributed by Andrew Cagney, with assistance from Mike Meissner.
4283 PSIM is a very elaborate model of the PowerPC, including not only
4284 basic instruction set execution, but also details of execution unit
4285 performance and I/O hardware. See sim/ppc/README for more details.
4289 GDB now works with Solaris 2.5.
4291 * Windows 95/NT native
4293 GDB will now work as a native debugger on Windows 95 and Windows NT.
4294 To build it from source, you must use the "gnu-win32" environment,
4295 which uses a DLL to emulate enough of Unix to run the GNU tools.
4296 Further information, binaries, and sources are available at
4297 ftp.cygnus.com, under pub/gnu-win32.
4299 * dont-repeat command
4301 If a user-defined command includes the command `dont-repeat', then the
4302 command will not be repeated if the user just types return. This is
4303 useful if the command is time-consuming to run, so that accidental
4304 extra keystrokes don't run the same command many times.
4306 * Send break instead of ^C
4308 The standard remote protocol now includes an option to send a break
4309 rather than a ^C to the target in order to interrupt it. By default,
4310 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4312 * Remote protocol timeout
4314 The standard remote protocol includes a new variable `remotetimeout'
4315 that allows you to set the number of seconds before GDB gives up trying
4316 to read from the target. The default value is 2.
4318 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4320 By default GDB will automatically keep track of objects as they are
4321 loaded and unloaded by the dynamic linker. By using the command `set
4322 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4323 when shared library events occur, thus allowing you to set breakpoints
4324 in shared libraries which are explicitly loaded by the inferior.
4326 Note this feature does not work on hpux8. On hpux9 you must link
4327 /usr/lib/end.o into your program. This feature should work
4328 automatically on hpux10.
4330 * Irix 5.x hardware watchpoint support
4332 Irix 5 configurations now support the use of hardware watchpoints.
4334 * Mips protocol "SYN garbage limit"
4336 When debugging a Mips target using the `target mips' protocol, you
4337 may set the number of characters that GDB will ignore by setting
4338 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4339 every character. The default value is 1050.
4341 * Recording and replaying remote debug sessions
4343 If you set `remotelogfile' to the name of a file, gdb will write to it
4344 a recording of a remote debug session. This recording may then be
4345 replayed back to gdb using "gdbreplay". See gdbserver/README for
4346 details. This is useful when you have a problem with GDB while doing
4347 remote debugging; you can make a recording of the session and send it
4348 to someone else, who can then recreate the problem.
4350 * Speedups for remote debugging
4352 GDB includes speedups for downloading and stepping MIPS systems using
4353 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4354 and more efficient S-record downloading.
4356 * Memory use reductions and statistics collection
4358 GDB now uses less memory and reports statistics about memory usage.
4359 Try the `maint print statistics' command, for example.
4361 *** Changes in GDB-4.15:
4363 * Psymtabs for XCOFF
4365 The symbol reader for AIX GDB now uses partial symbol tables. This
4366 can greatly improve startup time, especially for large executables.
4368 * Remote targets use caching
4370 Remote targets now use a data cache to speed up communication with the
4371 remote side. The data cache could lead to incorrect results because
4372 it doesn't know about volatile variables, thus making it impossible to
4373 debug targets which use memory mapped I/O devices. `set remotecache
4374 off' turns the the data cache off.
4376 * Remote targets may have threads
4378 The standard remote protocol now includes support for multiple threads
4379 in the target system, using new protocol commands 'H' and 'T'. See
4380 gdb/remote.c for details.
4384 If GDB is configured with `--enable-netrom', then it will include
4385 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4386 acts as though it is a bank of ROM on the target board, but you can
4387 write into it over the network. GDB's support consists only of
4388 support for fast loading into the emulated ROM; to debug, you must use
4389 another protocol, such as standard remote protocol. The usual
4390 sequence is something like
4392 target nrom <netrom-hostname>
4394 target remote <netrom-hostname>:1235
4398 GDB now includes support for the Apple Macintosh, as a host only. It
4399 may be run as either an MPW tool or as a standalone application, and
4400 it can debug through the serial port. All the usual GDB commands are
4401 available, but to the target command, you must supply "serial" as the
4402 device type instead of "/dev/ttyXX". See mpw-README in the main
4403 directory for more information on how to build. The MPW configuration
4404 scripts */mpw-config.in support only a few targets, and only the
4405 mips-idt-ecoff target has been tested.
4409 GDB configuration now uses autoconf. This is not user-visible,
4410 but does simplify configuration and building.
4414 GDB now supports hpux10.
4416 *** Changes in GDB-4.14:
4418 * New native configurations
4420 x86 FreeBSD i[345]86-*-freebsd
4421 x86 NetBSD i[345]86-*-netbsd
4422 NS32k NetBSD ns32k-*-netbsd
4423 Sparc NetBSD sparc-*-netbsd
4427 A29K VxWorks a29k-*-vxworks
4428 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4429 CPU32 EST-300 emulator m68*-*-est*
4430 PowerPC ELF powerpc-*-elf
4433 * Alpha OSF/1 support for procfs
4435 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4436 possible to attach to running processes. As the mounting of the /proc
4437 filesystem is optional on the Alpha, GDB automatically determines
4438 the availability of /proc during startup. This can lead to problems
4439 if /proc is unmounted after GDB has been started.
4441 * Arguments to user-defined commands
4443 User commands may accept up to 10 arguments separated by whitespace.
4444 Arguments are accessed within the user command via $arg0..$arg9. A
4447 print $arg0 + $arg1 + $arg2
4449 To execute the command use:
4452 Defines the command "adder" which prints the sum of its three arguments.
4453 Note the arguments are text substitutions, so they may reference variables,
4454 use complex expressions, or even perform inferior function calls.
4456 * New `if' and `while' commands
4458 This makes it possible to write more sophisticated user-defined
4459 commands. Both commands take a single argument, which is the
4460 expression to evaluate, and must be followed by the commands to
4461 execute, one per line, if the expression is nonzero, the list being
4462 terminated by the word `end'. The `if' command list may include an
4463 `else' word, which causes the following commands to be executed only
4464 if the expression is zero.
4466 * Fortran source language mode
4468 GDB now includes partial support for Fortran 77. It will recognize
4469 Fortran programs and can evaluate a subset of Fortran expressions, but
4470 variables and functions may not be handled correctly. GDB will work
4471 with G77, but does not yet know much about symbols emitted by other
4474 * Better HPUX support
4476 Most debugging facilities now work on dynamic executables for HPPAs
4477 running hpux9 or later. You can attach to running dynamically linked
4478 processes, but by default the dynamic libraries will be read-only, so
4479 for instance you won't be able to put breakpoints in them. To change
4480 that behavior do the following before running the program:
4486 This will cause the libraries to be mapped private and read-write.
4487 To revert to the normal behavior, do this:
4493 You cannot set breakpoints or examine data in the library until after
4494 the library is loaded if the function/data symbols do not have
4497 GDB can now also read debug symbols produced by the HP C compiler on
4498 HPPAs (sorry, no C++, Fortran or 68k support).
4500 * Target byte order now dynamically selectable
4502 You can choose which byte order to use with a target system, via the
4503 commands "set endian big" and "set endian little", and you can see the
4504 current setting by using "show endian". You can also give the command
4505 "set endian auto", in which case GDB will use the byte order
4506 associated with the executable. Currently, only embedded MIPS
4507 configurations support dynamic selection of target byte order.
4509 * New DOS host serial code
4511 This version uses DPMI interrupts to handle buffered I/O, so you
4512 no longer need to run asynctsr when debugging boards connected to
4515 *** Changes in GDB-4.13:
4517 * New "complete" command
4519 This lists all the possible completions for the rest of the line, if it
4520 were to be given as a command itself. This is intended for use by emacs.
4522 * Trailing space optional in prompt
4524 "set prompt" no longer adds a space for you after the prompt you set. This
4525 allows you to set a prompt which ends in a space or one that does not.
4527 * Breakpoint hit counts
4529 "info break" now displays a count of the number of times the breakpoint
4530 has been hit. This is especially useful in conjunction with "ignore"; you
4531 can ignore a large number of breakpoint hits, look at the breakpoint info
4532 to see how many times the breakpoint was hit, then run again, ignoring one
4533 less than that number, and this will get you quickly to the last hit of
4536 * Ability to stop printing at NULL character
4538 "set print null-stop" will cause GDB to stop printing the characters of
4539 an array when the first NULL is encountered. This is useful when large
4540 arrays actually contain only short strings.
4542 * Shared library breakpoints
4544 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4545 breakpoints in shared libraries before the executable is run.
4547 * Hardware watchpoints
4549 There is a new hardware breakpoint for the watch command for sparclite
4550 targets. See gdb/sparclite/hw_breakpoint.note.
4552 Hardware watchpoints are also now supported under GNU/Linux.
4556 Annotations have been added. These are for use with graphical interfaces,
4557 and are still experimental. Currently only gdba.el uses these.
4559 * Improved Irix 5 support
4561 GDB now works properly with Irix 5.2.
4563 * Improved HPPA support
4565 GDB now works properly with the latest GCC and GAS.
4567 * New native configurations
4569 Sequent PTX4 i[34]86-sequent-ptx4
4570 HPPA running OSF/1 hppa*-*-osf*
4571 Atari TT running SVR4 m68*-*-sysv4*
4572 RS/6000 LynxOS rs6000-*-lynxos*
4576 OS/9000 i[34]86-*-os9k
4577 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4580 * Hitachi SH7000 and E7000-PC ICE support
4582 There is now support for communicating with the Hitachi E7000-PC ICE.
4583 This is available automatically when GDB is configured for the SH.
4587 As usual, a variety of small fixes and improvements, both generic
4588 and configuration-specific. See the ChangeLog for more detail.
4590 *** Changes in GDB-4.12:
4592 * Irix 5 is now supported
4596 GDB-4.12 on the HPPA has a number of changes which make it unable
4597 to debug the output from the currently released versions of GCC and
4598 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4599 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4600 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4603 *** Changes in GDB-4.11:
4605 * User visible changes:
4609 The "set remotedebug" option is now consistent between the mips remote
4610 target, remote targets using the gdb-specific protocol, UDI (AMD's
4611 debug protocol for the 29k) and the 88k bug monitor. It is now an
4612 integer specifying a debug level (normally 0 or 1, but 2 means more
4613 debugging info for the mips target).
4615 * DEC Alpha native support
4617 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4618 debug info, but GDB works fairly well with the DEC compiler and should
4619 work with a future GCC release. See the README file for a few
4620 Alpha-specific notes.
4622 * Preliminary thread implementation
4624 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4626 * LynxOS native and target support for 386
4628 This release has been hosted on LynxOS 2.2, and also can be configured
4629 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4632 * Improvements in C++ mangling/demangling.
4634 This release has much better g++ debugging, specifically in name
4635 mangling/demangling, virtual function calls, print virtual table,
4636 call methods, ...etc.
4638 *** Changes in GDB-4.10:
4640 * User visible changes:
4642 Remote debugging using the GDB-specific (`target remote') protocol now
4643 supports the `load' command. This is only useful if you have some
4644 other way of getting the stub to the target system, and you can put it
4645 somewhere in memory where it won't get clobbered by the download.
4647 Filename completion now works.
4649 When run under emacs mode, the "info line" command now causes the
4650 arrow to point to the line specified. Also, "info line" prints
4651 addresses in symbolic form (as well as hex).
4653 All vxworks based targets now support a user settable option, called
4654 vxworks-timeout. This option represents the number of seconds gdb
4655 should wait for responses to rpc's. You might want to use this if
4656 your vxworks target is, perhaps, a slow software simulator or happens
4657 to be on the far side of a thin network line.
4661 This release contains support for using a DEC alpha as a GDB host for
4662 cross debugging. Native alpha debugging is not supported yet.
4665 *** Changes in GDB-4.9:
4669 This is the first GDB release which is accompanied by a matching testsuite.
4670 The testsuite requires installation of dejagnu, which should be available
4671 via ftp from most sites that carry GNU software.
4675 'Cfront' style demangling has had its name changed to 'ARM' style, to
4676 emphasize that it was written from the specifications in the C++ Annotated
4677 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4678 disclaimers, it still generated too much confusion with users attempting to
4679 use gdb with AT&T cfront.
4683 GDB now uses a standard remote interface to a simulator library.
4684 So far, the library contains simulators for the Zilog Z8001/2, the
4685 Hitachi H8/300, H8/500 and Super-H.
4687 * New targets supported
4689 H8/300 simulator h8300-hitachi-hms or h8300hms
4690 H8/500 simulator h8500-hitachi-hms or h8500hms
4691 SH simulator sh-hitachi-hms or sh
4692 Z8000 simulator z8k-zilog-none or z8ksim
4693 IDT MIPS board over serial line mips-idt-ecoff
4695 Cross-debugging to GO32 targets is supported. It requires a custom
4696 version of the i386-stub.c module which is integrated with the
4697 GO32 memory extender.
4699 * New remote protocols
4701 MIPS remote debugging protocol.
4703 * New source languages supported
4705 This version includes preliminary support for Chill, a Pascal like language
4706 used by telecommunications companies. Chill support is also being integrated
4707 into the GNU compiler, but we don't know when it will be publically available.
4710 *** Changes in GDB-4.8:
4712 * HP Precision Architecture supported
4714 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4715 version of this support was available as a set of patches from the
4716 University of Utah. GDB does not support debugging of programs
4717 compiled with the HP compiler, because HP will not document their file
4718 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4719 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4721 Many problems in the preliminary version have been fixed.
4723 * Faster and better demangling
4725 We have improved template demangling and fixed numerous bugs in the GNU style
4726 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4727 character types (wchar_t) are now supported. Demangling of each symbol is now
4728 only done once, and is cached when the symbol table for a file is read in.
4729 This results in a small increase in memory usage for C programs, a moderate
4730 increase in memory usage for C++ programs, and a fantastic speedup in
4733 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4734 from the specifications in the Annotated Reference Manual, which AT&T's
4735 compiler does not actually implement.
4737 * G++ multiple inheritance compiler problem
4739 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4740 inheritance lattices was reworked to properly discover ambiguities. We
4741 recently found an example which causes this new algorithm to fail in a
4742 very subtle way, producing bad debug information for those classes.
4743 The file 'gcc.patch' (in this directory) can be applied to gcc to
4744 circumvent the problem. A future GCC release will contain a complete
4747 The previous G++ debug info problem (mentioned below for the gdb-4.7
4748 release) is fixed in gcc version 2.3.2.
4750 * Improved configure script
4752 The `configure' script will now attempt to guess your system type if
4753 you don't supply a host system type. The old scheme of supplying a
4754 host system triplet is preferable over using this. All the magic is
4755 done in the new `config.guess' script. Examine it for details.
4757 We have also brought our configure script much more in line with the FSF's
4758 version. It now supports the --with-xxx options. In particular,
4759 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4760 The resulting GDB will not be able to read arbitrary object file formats --
4761 only the format ``expected'' to be used on the configured target system.
4762 We hope to make this the default in a future release.
4764 * Documentation improvements
4766 There's new internal documentation on how to modify GDB, and how to
4767 produce clean changes to the code. We implore people to read it
4768 before submitting changes.
4770 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4771 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4772 `info' files are also provided. To build `info' files from scratch,
4773 you will need the latest `makeinfo' release, which will be available in
4774 a future texinfo-X.Y release.
4776 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4777 We're not sure exactly which versions have this problem, but it has
4778 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4779 or better. If that isn't possible, there is a patch in
4780 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4781 around this problem.
4785 GDB now supports array constants that can be used in expressions typed in by
4786 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4787 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4790 The new directory `gdb/sparclite' contains a program that demonstrates
4791 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4793 * New native hosts supported
4795 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4796 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4798 * New targets supported
4800 AMD 29k family via UDI a29k-amd-udi or udi29k
4802 * New file formats supported
4804 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4805 HPUX core files, and SCO 3.2v2 core files.
4809 Attaching to processes now works again; thanks for the many bug reports.
4811 We have also stomped on a bunch of core dumps caused by
4812 printf_filtered("%s") problems.
4814 We eliminated a copyright problem on the rpc and ptrace header files
4815 for VxWorks, which was discovered at the last minute during the 4.7
4816 release. You should now be able to build a VxWorks GDB.
4818 You can now interrupt gdb while an attached process is running. This
4819 will cause the attached process to stop, and give control back to GDB.
4821 We fixed problems caused by using too many file descriptors
4822 for reading symbols from object files and libraries. This was
4823 especially a problem for programs that used many (~100) shared
4826 The `step' command now only enters a subroutine if there is line number
4827 information for the subroutine. Otherwise it acts like the `next'
4828 command. Previously, `step' would enter subroutines if there was
4829 any debugging information about the routine. This avoids problems
4830 when using `cc -g1' on MIPS machines.
4832 * Internal improvements
4834 GDB's internal interfaces have been improved to make it easier to support
4835 debugging of multiple languages in the future.
4837 GDB now uses a common structure for symbol information internally.
4838 Minimal symbols (derived from linkage symbols in object files), partial
4839 symbols (from a quick scan of debug information), and full symbols
4840 contain a common subset of information, making it easier to write
4841 shared code that handles any of them.
4843 * New command line options
4845 We now accept --silent as an alias for --quiet.
4849 The memory-mapped-malloc library is now licensed under the GNU Library
4850 General Public License.
4852 *** Changes in GDB-4.7:
4854 * Host/native/target split
4856 GDB has had some major internal surgery to untangle the support for
4857 hosts and remote targets. Now, when you configure GDB for a remote
4858 target, it will no longer load in all of the support for debugging
4859 local programs on the host. When fully completed and tested, this will
4860 ensure that arbitrary host/target combinations are possible.
4862 The primary conceptual shift is to separate the non-portable code in
4863 GDB into three categories. Host specific code is required any time GDB
4864 is compiled on that host, regardless of the target. Target specific
4865 code relates to the peculiarities of the target, but can be compiled on
4866 any host. Native specific code is everything else: it can only be
4867 built when the host and target are the same system. Child process
4868 handling and core file support are two common `native' examples.
4870 GDB's use of /proc for controlling Unix child processes is now cleaner.
4871 It has been split out into a single module under the `target_ops' vector,
4872 plus two native-dependent functions for each system that uses /proc.
4874 * New hosts supported
4876 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4877 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4878 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4880 * New targets supported
4882 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4883 68030 and CPU32 m68030-*-*, m68332-*-*
4885 * New native hosts supported
4887 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4888 (386bsd is not well tested yet)
4889 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4891 * New file formats supported
4893 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4894 supports reading of `a.out.adobe' object files, which are an a.out
4895 format extended with minimal information about multiple sections.
4899 `show copying' is the same as the old `info copying'.
4900 `show warranty' is the same as `info warrantee'.
4901 These were renamed for consistency. The old commands continue to work.
4903 `info handle' is a new alias for `info signals'.
4905 You can now define pre-command hooks, which attach arbitrary command
4906 scripts to any command. The commands in the hook will be executed
4907 prior to the user's command. You can also create a hook which will be
4908 executed whenever the program stops. See gdb.texinfo.
4912 We now deal with Cfront style name mangling, and can even extract type
4913 info from mangled symbols. GDB can automatically figure out which
4914 symbol mangling style your C++ compiler uses.
4916 Calling of methods and virtual functions has been improved as well.
4920 The crash that occured when debugging Sun Ansi-C compiled binaries is
4921 fixed. This was due to mishandling of the extra N_SO stabs output
4924 We also finally got Ultrix 4.2 running in house, and fixed core file
4925 support, with help from a dozen people on the net.
4927 John M. Farrell discovered that the reason that single-stepping was so
4928 slow on all of the Mips based platforms (primarily SGI and DEC) was
4929 that we were trying to demangle and lookup a symbol used for internal
4930 purposes on every instruction that was being stepped through. Changing
4931 the name of that symbol so that it couldn't be mistaken for a C++
4932 mangled symbol sped things up a great deal.
4934 Rich Pixley sped up symbol lookups in general by getting much smarter
4935 about when C++ symbol mangling is necessary. This should make symbol
4936 completion (TAB on the command line) much faster. It's not as fast as
4937 we'd like, but it's significantly faster than gdb-4.6.
4941 A new user controllable variable 'call_scratch_address' can
4942 specify the location of a scratch area to be used when GDB
4943 calls a function in the target. This is necessary because the
4944 usual method of putting the scratch area on the stack does not work
4945 in systems that have separate instruction and data spaces.
4947 We integrated changes to support the 29k UDI (Universal Debugger
4948 Interface), but discovered at the last minute that we didn't have all
4949 of the appropriate copyright paperwork. We are working with AMD to
4950 resolve this, and hope to have it available soon.
4954 We have sped up the remote serial line protocol, especially for targets
4955 with lots of registers. It now supports a new `expedited status' ('T')
4956 message which can be used in place of the existing 'S' status message.
4957 This allows the remote stub to send only the registers that GDB
4958 needs to make a quick decision about single-stepping or conditional
4959 breakpoints, eliminating the need to fetch the entire register set for
4960 each instruction being stepped through.
4962 The GDB remote serial protocol now implements a write-through cache for
4963 registers, only re-reading the registers if the target has run.
4965 There is also a new remote serial stub for SPARC processors. You can
4966 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4967 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4968 processor with a serial port.
4972 Configure.in files have become much easier to read and modify. A new
4973 `table driven' format makes it more obvious what configurations are
4974 supported, and what files each one uses.
4978 There is a new opcodes library which will eventually contain all of the
4979 disassembly routines and opcode tables. At present, it only contains
4980 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4981 disassembler (binutils/objdump) to share these routines.
4983 The libiberty library is now copylefted under the GNU Library General
4984 Public License. This allows more liberal use, and was done so libg++
4985 can use it. This makes no difference to GDB, since the Library License
4986 grants all the rights from the General Public License.
4990 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4991 reference to the stabs symbol info used by the debugger. It is (as far
4992 as we know) the only published document on this fascinating topic. We
4993 encourage you to read it, compare it to the stabs information on your
4994 system, and send improvements on the document in general (to
4995 bug-gdb@prep.ai.mit.edu).
4997 And, of course, many bugs have been fixed.
5000 *** Changes in GDB-4.6:
5002 * Better support for C++ function names
5004 GDB now accepts as input the "demangled form" of C++ overloaded function
5005 names and member function names, and can do command completion on such names
5006 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5007 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5008 Make use of command completion, it is your friend.
5010 GDB also now accepts a variety of C++ mangled symbol formats. They are
5011 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5012 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5013 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5014 for the list of formats.
5016 * G++ symbol mangling problem
5018 Recent versions of gcc have a bug in how they emit debugging information for
5019 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5020 directory) can be applied to gcc to fix the problem. Alternatively, if you
5021 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5022 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5023 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5026 * New 'maintenance' command
5028 All of the commands related to hacking GDB internals have been moved out of
5029 the main command set, and now live behind the 'maintenance' command. This
5030 can also be abbreviated as 'mt'. The following changes were made:
5032 dump-me -> maintenance dump-me
5033 info all-breakpoints -> maintenance info breakpoints
5034 printmsyms -> maintenance print msyms
5035 printobjfiles -> maintenance print objfiles
5036 printpsyms -> maintenance print psymbols
5037 printsyms -> maintenance print symbols
5039 The following commands are new:
5041 maintenance demangle Call internal GDB demangler routine to
5042 demangle a C++ link name and prints the result.
5043 maintenance print type Print a type chain for a given symbol
5045 * Change to .gdbinit file processing
5047 We now read the $HOME/.gdbinit file before processing the argv arguments
5048 (e.g. reading symbol files or core files). This allows global parameters to
5049 be set, which will apply during the symbol reading. The ./.gdbinit is still
5050 read after argv processing.
5052 * New hosts supported
5054 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5056 GNU/Linux support i386-unknown-linux or linux
5058 We are also including code to support the HP/PA running BSD and HPUX. This
5059 is almost guaranteed not to work, as we didn't have time to test or build it
5060 for this release. We are including it so that the more adventurous (or
5061 masochistic) of you can play with it. We also had major problems with the
5062 fact that the compiler that we got from HP doesn't support the -g option.
5065 * New targets supported
5067 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5069 * More smarts about finding #include files
5071 GDB now remembers the compilation directory for all include files, and for
5072 all files from which C is generated (like yacc and lex sources). This
5073 greatly improves GDB's ability to find yacc/lex sources, and include files,
5074 especially if you are debugging your program from a directory different from
5075 the one that contains your sources.
5077 We also fixed a bug which caused difficulty with listing and setting
5078 breakpoints in include files which contain C code. (In the past, you had to
5079 try twice in order to list an include file that you hadn't looked at before.)
5081 * Interesting infernals change
5083 GDB now deals with arbitrary numbers of sections, where the symbols for each
5084 section must be relocated relative to that section's landing place in the
5085 target's address space. This work was needed to support ELF with embedded
5086 stabs used by Solaris-2.0.
5088 * Bug fixes (of course!)
5090 There have been loads of fixes for the following things:
5091 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5092 i960, stabs, DOS(GO32), procfs, etc...
5094 See the ChangeLog for details.
5096 *** Changes in GDB-4.5:
5098 * New machines supported (host and target)
5100 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5102 SGI Irix-4.x mips-sgi-irix4 or iris4
5104 * New malloc package
5106 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5107 Mmalloc is capable of handling mutiple heaps of memory. It is also
5108 capable of saving a heap to a file, and then mapping it back in later.
5109 This can be used to greatly speedup the startup of GDB by using a
5110 pre-parsed symbol table which lives in a mmalloc managed heap. For
5111 more details, please read mmalloc/mmalloc.texi.
5115 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5116 'help info proc' for details.
5118 * MIPS ecoff symbol table format
5120 The code that reads MIPS symbol table format is now supported on all hosts.
5121 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5124 * File name changes for MS-DOS
5126 Many files in the config directories have been renamed to make it easier to
5127 support GDB on MS-DOSe systems (which have very restrictive file name
5128 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5129 environment) is close to working but has some remaining problems. Note
5130 that debugging of DOS programs is not supported, due to limitations
5131 in the ``operating system'', but it can be used to host cross-debugging.
5133 * Cross byte order fixes
5135 Many fixes have been made to support cross debugging of Sparc and MIPS
5136 targets from hosts whose byte order differs.
5138 * New -mapped and -readnow options
5140 If memory-mapped files are available on your system through the 'mmap'
5141 system call, you can use the -mapped option on the `file' or
5142 `symbol-file' commands to cause GDB to write the symbols from your
5143 program into a reusable file. If the program you are debugging is
5144 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5145 Future GDB debugging sessions will notice the presence of this file,
5146 and will quickly map in symbol information from it, rather than reading
5147 the symbol table from the executable program. Using the '-mapped'
5148 option in a GDB `file' or `symbol-file' command has the same effect as
5149 starting GDB with the '-mapped' command-line option.
5151 You can cause GDB to read the entire symbol table immediately by using
5152 the '-readnow' option with any of the commands that load symbol table
5153 information (or on the GDB command line). This makes the command
5154 slower, but makes future operations faster.
5156 The -mapped and -readnow options are typically combined in order to
5157 build a `fred.syms' file that contains complete symbol information.
5158 A simple GDB invocation to do nothing but build a `.syms' file for future
5161 gdb -batch -nx -mapped -readnow programname
5163 The `.syms' file is specific to the host machine on which GDB is run.
5164 It holds an exact image of GDB's internal symbol table. It cannot be
5165 shared across multiple host platforms.
5167 * longjmp() handling
5169 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5170 siglongjmp() without losing control. This feature has not yet been ported to
5171 all systems. It currently works on many 386 platforms, all MIPS-based
5172 platforms (SGI, DECstation, etc), and Sun3/4.
5176 Preliminary work has been put in to support the new Solaris OS from Sun. At
5177 this time, it can control and debug processes, but it is not capable of
5182 As always, many many bug fixes. The major areas were with g++, and mipsread.
5183 People using the MIPS-based platforms should experience fewer mysterious
5184 crashes and trashed symbol tables.
5186 *** Changes in GDB-4.4:
5188 * New machines supported (host and target)
5190 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5192 BSD Reno on Vax vax-dec-bsd
5193 Ultrix on Vax vax-dec-ultrix
5195 * New machines supported (target)
5197 AMD 29000 embedded, using EBMON a29k-none-none
5201 GDB continues to improve its handling of C++. `References' work better.
5202 The demangler has also been improved, and now deals with symbols mangled as
5203 per the Annotated C++ Reference Guide.
5205 GDB also now handles `stabs' symbol information embedded in MIPS
5206 `ecoff' symbol tables. Since the ecoff format was not easily
5207 extensible to handle new languages such as C++, this appeared to be a
5208 good way to put C++ debugging info into MIPS binaries. This option
5209 will be supported in the GNU C compiler, version 2, when it is
5212 * New features for SVR4
5214 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5215 shared libraries. Debugging dynamically linked programs should present
5216 only minor differences from debugging statically linked programs.
5218 The `info proc' command will print out information about any process
5219 on an SVR4 system (including the one you are debugging). At the moment,
5220 it prints the address mappings of the process.
5222 If you bring up GDB on another SVR4 system, please send mail to
5223 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5225 * Better dynamic linking support in SunOS
5227 Reading symbols from shared libraries which contain debugging symbols
5228 now works properly. However, there remain issues such as automatic
5229 skipping of `transfer vector' code during function calls, which
5230 make it harder to debug code in a shared library, than to debug the
5231 same code linked statically.
5235 GDB is now using the latest `getopt' routines from the FSF. This
5236 version accepts the -- prefix for options with long names. GDB will
5237 continue to accept the old forms (-option and +option) as well.
5238 Various single letter abbreviations for options have been explicity
5239 added to the option table so that they won't get overshadowed in the
5240 future by other options that begin with the same letter.
5244 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5245 Many assorted bugs have been handled. Many more remain to be handled.
5246 See the various ChangeLog files (primarily in gdb and bfd) for details.
5249 *** Changes in GDB-4.3:
5251 * New machines supported (host and target)
5253 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5254 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5255 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5257 * Almost SCO Unix support
5259 We had hoped to support:
5260 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5261 (except for core file support), but we discovered very late in the release
5262 that it has problems with process groups that render gdb unusable. Sorry
5263 about that. I encourage people to fix it and post the fixes.
5265 * Preliminary ELF and DWARF support
5267 GDB can read ELF object files on System V Release 4, and can handle
5268 debugging records for C, in DWARF format, in ELF files. This support
5269 is preliminary. If you bring up GDB on another SVR4 system, please
5270 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5275 GDB now uses the latest `readline' library. One user-visible change
5276 is that two tabs will list possible command completions, which previously
5277 required typing M-? (meta-question mark, or ESC ?).
5281 The `stepi' bug that many of you noticed has been squashed.
5282 Many bugs in C++ have been handled. Many more remain to be handled.
5283 See the various ChangeLog files (primarily in gdb and bfd) for details.
5285 * State of the MIPS world (in case you wondered):
5287 GDB can understand the symbol tables emitted by the compilers
5288 supplied by most vendors of MIPS-based machines, including DEC. These
5289 symbol tables are in a format that essentially nobody else uses.
5291 Some versions of gcc come with an assembler post-processor called
5292 mips-tfile. This program is required if you want to do source-level
5293 debugging of gcc-compiled programs. I believe FSF does not ship
5294 mips-tfile with gcc version 1, but it will eventually come with gcc
5297 Debugging of g++ output remains a problem. g++ version 1.xx does not
5298 really support it at all. (If you're lucky, you should be able to get
5299 line numbers and stack traces to work, but no parameters or local
5300 variables.) With some work it should be possible to improve the
5303 When gcc version 2 is released, you will have somewhat better luck.
5304 However, even then you will get confusing results for inheritance and
5307 We will eventually provide full debugging of g++ output on
5308 DECstations. This will probably involve some kind of stabs-in-ecoff
5309 encapulation, but the details have not been worked out yet.
5312 *** Changes in GDB-4.2:
5314 * Improved configuration
5316 Only one copy of `configure' exists now, and it is not self-modifying.
5317 Porting BFD is simpler.
5321 The `step' and `next' commands now only stop at the first instruction
5322 of a source line. This prevents the multiple stops that used to occur
5323 in switch statements, for-loops, etc. `Step' continues to stop if a
5324 function that has debugging information is called within the line.
5328 Lots of small bugs fixed. More remain.
5330 * New host supported (not target)
5332 Intel 386 PC clone running Mach i386-none-mach
5335 *** Changes in GDB-4.1:
5337 * Multiple source language support
5339 GDB now has internal scaffolding to handle several source languages.
5340 It determines the type of each source file from its filename extension,
5341 and will switch expression parsing and number formatting to match the
5342 language of the function in the currently selected stack frame.
5343 You can also specifically set the language to be used, with
5344 `set language c' or `set language modula-2'.
5348 GDB now has preliminary support for the GNU Modula-2 compiler,
5349 currently under development at the State University of New York at
5350 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5351 continue through the fall of 1991 and into 1992.
5353 Other Modula-2 compilers are currently not supported, and attempting to
5354 debug programs compiled with them will likely result in an error as the
5355 symbol table is read. Feel free to work on it, though!
5357 There are hooks in GDB for strict type checking and range checking,
5358 in the `Modula-2 philosophy', but they do not currently work.
5362 GDB can now write to executable and core files (e.g. patch
5363 a variable's value). You must turn this switch on, specify
5364 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5365 by assigning a new value to a variable. Modifications take
5368 * Automatic SunOS shared library reading
5370 When you run your program, GDB automatically determines where its
5371 shared libraries (if any) have been loaded, and reads their symbols.
5372 The `share' command is no longer needed. This also works when
5373 examining core files.
5377 You can specify the number of lines that the `list' command shows.
5380 * New machines supported (host and target)
5382 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5383 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5384 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5386 * New hosts supported (not targets)
5388 IBM RT/PC: romp-ibm-aix or rtpc
5390 * New targets supported (not hosts)
5392 AMD 29000 embedded with COFF a29k-none-coff
5393 AMD 29000 embedded with a.out a29k-none-aout
5394 Ultracomputer remote kernel debug a29k-nyu-kern
5396 * New remote interfaces
5402 *** Changes in GDB-4.0:
5406 Wide output is wrapped at good places to make the output more readable.
5408 Gdb now supports cross-debugging from a host machine of one type to a
5409 target machine of another type. Communication with the target system
5410 is over serial lines. The ``target'' command handles connecting to the
5411 remote system; the ``load'' command will download a program into the
5412 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5413 also supports debugging of realtime processes running under VxWorks,
5414 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5415 stub on the target system.
5417 New CPUs supported include the AMD 29000 and Intel 960.
5419 GDB now reads object files and symbol tables via a ``binary file''
5420 library, which allows a single copy of GDB to debug programs of multiple
5421 object file types such as a.out and coff.
5423 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5424 refcard.dvi and refcard.ps are available to format it).
5427 * Control-Variable user interface simplified
5429 All variables that control the operation of the debugger can be set
5430 by the ``set'' command, and displayed by the ``show'' command.
5432 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5433 ``Show prompt'' produces the response:
5434 Gdb's prompt is new-gdb=>.
5436 What follows are the NEW set commands. The command ``help set'' will
5437 print a complete list of old and new set commands. ``help set FOO''
5438 will give a longer description of the variable FOO. ``show'' will show
5439 all of the variable descriptions and their current settings.
5441 confirm on/off: Enables warning questions for operations that are
5442 hard to recover from, e.g. rerunning the program while
5443 it is already running. Default is ON.
5445 editing on/off: Enables EMACS style command line editing
5446 of input. Previous lines can be recalled with
5447 control-P, the current line can be edited with control-B,
5448 you can search for commands with control-R, etc.
5451 history filename NAME: NAME is where the gdb command history
5452 will be stored. The default is .gdb_history,
5453 or the value of the environment variable
5456 history size N: The size, in commands, of the command history. The
5457 default is 256, or the value of the environment variable
5460 history save on/off: If this value is set to ON, the history file will
5461 be saved after exiting gdb. If set to OFF, the
5462 file will not be saved. The default is OFF.
5464 history expansion on/off: If this value is set to ON, then csh-like
5465 history expansion will be performed on
5466 command line input. The default is OFF.
5468 radix N: Sets the default radix for input and output. It can be set
5469 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5470 in the current radix, so "set radix 10" is always a no-op.
5472 height N: This integer value is the number of lines on a page. Default
5473 is 24, the current `stty rows'' setting, or the ``li#''
5474 setting from the termcap entry matching the environment
5477 width N: This integer value is the number of characters on a line.
5478 Default is 80, the current `stty cols'' setting, or the ``co#''
5479 setting from the termcap entry matching the environment
5482 Note: ``set screensize'' is obsolete. Use ``set height'' and
5483 ``set width'' instead.
5485 print address on/off: Print memory addresses in various command displays,
5486 such as stack traces and structure values. Gdb looks
5487 more ``symbolic'' if you turn this off; it looks more
5488 ``machine level'' with it on. Default is ON.
5490 print array on/off: Prettyprint arrays. New convenient format! Default
5493 print demangle on/off: Print C++ symbols in "source" form if on,
5496 print asm-demangle on/off: Same, for assembler level printouts
5499 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5502 * Support for Epoch Environment.
5504 The epoch environment is a version of Emacs v18 with windowing. One
5505 new command, ``inspect'', is identical to ``print'', except that if you
5506 are running in the epoch environment, the value is printed in its own
5510 * Support for Shared Libraries
5512 GDB can now debug programs and core files that use SunOS shared libraries.
5513 Symbols from a shared library cannot be referenced
5514 before the shared library has been linked with the program (this
5515 happens after you type ``run'' and before the function main() is entered).
5516 At any time after this linking (including when examining core files
5517 from dynamically linked programs), gdb reads the symbols from each
5518 shared library when you type the ``sharedlibrary'' command.
5519 It can be abbreviated ``share''.
5521 sharedlibrary REGEXP: Load shared object library symbols for files
5522 matching a unix regular expression. No argument
5523 indicates to load symbols for all shared libraries.
5525 info sharedlibrary: Status of loaded shared libraries.
5530 A watchpoint stops execution of a program whenever the value of an
5531 expression changes. Checking for this slows down execution
5532 tremendously whenever you are in the scope of the expression, but is
5533 quite useful for catching tough ``bit-spreader'' or pointer misuse
5534 problems. Some machines such as the 386 have hardware for doing this
5535 more quickly, and future versions of gdb will use this hardware.
5537 watch EXP: Set a watchpoint (breakpoint) for an expression.
5539 info watchpoints: Information about your watchpoints.
5541 delete N: Deletes watchpoint number N (same as breakpoints).
5542 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5543 enable N: Re-enables watchpoint number N (same as breakpoints).
5546 * C++ multiple inheritance
5548 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5551 * C++ exception handling
5553 Gdb now supports limited C++ exception handling. Besides the existing
5554 ability to breakpoint on an exception handler, gdb can breakpoint on
5555 the raising of an exception (before the stack is peeled back to the
5558 catch FOO: If there is a FOO exception handler in the dynamic scope,
5559 set a breakpoint to catch exceptions which may be raised there.
5560 Multiple exceptions (``catch foo bar baz'') may be caught.
5562 info catch: Lists all exceptions which may be caught in the
5563 current stack frame.
5566 * Minor command changes
5568 The command ``call func (arg, arg, ...)'' now acts like the print
5569 command, except it does not print or save a value if the function's result
5570 is void. This is similar to dbx usage.
5572 The ``up'' and ``down'' commands now always print the frame they end up
5573 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5574 frames without printing.
5576 * New directory command
5578 'dir' now adds directories to the FRONT of the source search path.
5579 The path starts off empty. Source files that contain debug information
5580 about the directory in which they were compiled can be found even
5581 with an empty path; Sun CC and GCC include this information. If GDB can't
5582 find your source file in the current directory, type "dir .".
5584 * Configuring GDB for compilation
5586 For normal use, type ``./configure host''. See README or gdb.texinfo
5589 GDB now handles cross debugging. If you are remotely debugging between
5590 two different machines, type ``./configure host -target=targ''.
5591 Host is the machine where GDB will run; targ is the machine
5592 where the program that you are debugging will run.
5594 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.