1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * GDB now supports Fission DWP file format version 2.
7 http://gcc.gnu.org/wiki/DebugFission
9 * New convenience function "$_isvoid", to check whether an expression
10 is void. A void expression is an expression where the type of the
11 result is "void". For example, some convenience variables may be
12 "void" when evaluated (e.g., "$_exitcode" before the execution of
13 the program being debugged; or an undefined convenience variable).
14 Another example, when calling a function whose return type is
17 * The "maintenance print objfiles" command now takes an optional regexp.
19 * The "catch syscall" command now works on arm*-linux* targets.
21 * GDB now consistently shows "<not saved>" when printing values of
22 registers the debug info indicates have not been saved in the frame
23 and there's nowhere to retrieve them from
24 (callee-saved/call-clobbered registers):
29 (gdb) info registers rax
32 Before, the former would print "<optimized out>", and the latter
33 "*value not available*".
37 ** Frame filters and frame decorators have been added.
38 ** Temporary breakpoints are now supported.
39 ** Line tables representation has been added.
43 Nios II ELF nios2*-*-elf
44 Nios II GNU/Linux nios2*-*-linux
45 Texas Instruments MSP430 msp430*-*-elf
47 * Removed native configurations
49 Support for these a.out NetBSD and OpenBSD obsolete configurations has
50 been removed. ELF variants of these configurations are kept supported.
52 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
53 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
54 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
55 i[34567]86-*-openbsd3.[0-3]
56 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
57 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
58 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
62 Like "catch throw", but catches a re-thrown exception.
64 Renamed from old "maint check-symtabs".
66 Perform consistency checks on symtabs.
68 Expand symtabs matching an optional regexp.
71 Display the details of GDB configure-time options.
73 maint set|show per-command
74 maint set|show per-command space
75 maint set|show per-command time
76 maint set|show per-command symtab
77 Enable display of per-command gdb resource usage.
79 remove-symbol-file FILENAME
80 remove-symbol-file -a ADDRESS
81 Remove a symbol file added via add-symbol-file. The file to remove
82 can be identified by its filename or by an address that lies within
83 the boundaries of this symbol file in memory.
86 info exceptions REGEXP
87 Display the list of Ada exceptions defined in the program being
88 debugged. If provided, only the exceptions whose names match REGEXP
93 set debug symfile off|on
95 Control display of debugging info regarding reading symbol files and
96 symbol tables within those files
98 set print raw frame-arguments
99 show print raw frame-arguments
100 Set/show whether to print frame arguments in raw mode,
101 disregarding any defined pretty-printers.
103 set remote trace-status-packet
104 show remote trace-status-packet
105 Set/show the use of remote protocol qTStatus packet.
109 Control display of debugging messages related to Nios II targets.
113 Control whether target-assisted range stepping is enabled.
115 set startup-with-shell
116 show startup-with-shell
117 Specifies whether Unix child processes are started via a shell or
120 * You can now use a literal value 'unlimited' for options that
121 interpret 0 or -1 as meaning "unlimited". E.g., "set
122 trace-buffer-size unlimited" is now an alias for "set
123 trace-buffer-size -1" and "set height unlimited" is now an alias for
126 * The "set debug symtab-create" debugging option of GDB has been changed to
127 accept a verbosity level. 0 means "off", 1 provides basic debugging
128 output, and values of 2 or greater provides more verbose output.
130 * New command-line options
132 Display the details of GDB configure-time options.
134 * The command 'tsave' can now support new option '-ctf' to save trace
135 buffer in Common Trace Format.
137 * Newly installed $prefix/bin/gcore acts as a shell interface for the
140 * GDB now implements the the C++ 'typeid' operator.
142 * The new convenience variable $_exception holds the exception being
143 thrown or caught at an exception-related catchpoint.
145 * The exception-related catchpoints, like "catch throw", now accept a
146 regular expression which can be used to filter exceptions by type.
148 * The new convenience variable $_exitsignal is automatically set to
149 the terminating signal number when the program being debugged dies
150 due to an uncaught signal.
154 ** The -trace-save MI command can optionally save trace buffer in Common
157 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
159 ** The command -data-list-register-values now accepts an optional
160 "--skip-unavailable" option. When used, only the available registers
163 ** The new command -trace-frame-collected dumps collected variables,
164 computed expressions, tvars, memory and registers in a traceframe.
166 ** The commands -stack-list-locals, -stack-list-arguments and
167 -stack-list-variables now accept an option "--skip-unavailable".
168 When used, only the available locals or arguments are displayed.
170 ** The -exec-run command now accepts an optional "--start" option.
171 When used, the command follows the same semantics as the "start"
172 command, stopping the program's execution at the start of its
175 ** The new commands -catch-assert and -catch-exceptions insert
176 catchpoints stopping the program when Ada exceptions are raised.
178 ** The new command -info-ada-exceptions provides the equivalent of
179 the new "info exceptions" command.
181 * New system-wide configuration scripts
182 A GDB installation now provides scripts suitable for use as system-wide
183 configuration scripts for the following systems:
187 * GDB now supports target-assigned range stepping with remote targets.
188 This improves the performance of stepping source lines by reducing
189 the number of control packets from/to GDB. See "New remote packets"
192 * GDB now understands the element 'tvar' in the XML traceframe info.
193 It has the id of the collected trace state variables.
195 * On S/390 targets that provide the transactional-execution feature,
196 the program interruption transaction diagnostic block (TDB) is now
197 represented as a number of additional "registers" in GDB.
203 The vCont packet supports a new 'r' action, that tells the remote
204 stub to step through an address range itself, without GDB
205 involvemement at each single-step.
207 qXfer:libraries-svr4:read's annex
208 The previously unused annex of the qXfer:libraries-svr4:read packet
209 is now used to support passing an argument list. The remote stub
210 reports support for this argument list to GDB's qSupported query.
211 The defined arguments are "start" and "prev", used to reduce work
212 necessary for library list updating, resulting in significant
215 * New features in the GDB remote stub, GDBserver
217 ** GDBserver now supports target-assisted range stepping. Currently
218 enabled on x86/x86_64 GNU/Linux targets.
220 ** GDBserver now adds element 'tvar' in the XML in the reply to
221 'qXfer:traceframe-info:read'. It has the id of the collected
222 trace state variables.
224 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
227 * New 'z' formatter for printing and examining memory, this displays the
228 value as hexadecimal zero padded on the left to the size of the type.
230 * GDB can now use Windows x64 unwinding data.
232 * The "set remotebaud" command has been replaced by "set serial baud".
233 Similarly, "show remotebaud" has been replaced by "show serial baud".
234 The "set remotebaud" and "show remotebaud" commands are still available
235 to provide backward compatibility with older versions of GDB.
237 *** Changes in GDB 7.6
239 * Target record has been renamed to record-full.
240 Record/replay is now enabled with the "record full" command.
241 This also affects settings that are associated with full record/replay
242 that have been moved from "set/show record" to "set/show record full":
244 set|show record full insn-number-max
245 set|show record full stop-at-limit
246 set|show record full memory-query
248 * A new record target "record-btrace" has been added. The new target
249 uses hardware support to record the control-flow of a process. It
250 does not support replaying the execution, but it implements the
251 below new commands for investigating the recorded execution log.
252 This new recording method can be enabled using:
256 The "record-btrace" target is only available on Intel Atom processors
257 and requires a Linux kernel 2.6.32 or later.
259 * Two new commands have been added for record/replay to give information
260 about the recorded execution without having to replay the execution.
261 The commands are only supported by "record btrace".
263 record instruction-history prints the execution history at
264 instruction granularity
266 record function-call-history prints the execution history at
269 * New native configurations
271 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
272 FreeBSD/powerpc powerpc*-*-freebsd
273 x86_64/Cygwin x86_64-*-cygwin*
274 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
278 ARM AArch64 aarch64*-*-elf
279 ARM AArch64 GNU/Linux aarch64*-*-linux
280 Lynx 178 PowerPC powerpc-*-lynx*178
281 x86_64/Cygwin x86_64-*-cygwin*
282 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
284 * If the configured location of system.gdbinit file (as given by the
285 --with-system-gdbinit option at configure time) is in the
286 data-directory (as specified by --with-gdb-datadir at configure
287 time) or in one of its subdirectories, then GDB will look for the
288 system-wide init file in the directory specified by the
289 --data-directory command-line option.
291 * New command line options:
293 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
294 other initialization files, unlike -nx which disables all of them.
296 * Removed command line options
298 -epoch This was used by the gdb mode in Epoch, an ancient fork of
301 * The 'ptype' and 'whatis' commands now accept an argument to control
304 * 'info proc' now works on some core files.
308 ** Vectors can be created with gdb.Type.vector.
310 ** Python's atexit.register now works in GDB.
312 ** Types can be pretty-printed via a Python API.
314 ** Python 3 is now supported (in addition to Python 2.4 or later)
316 ** New class gdb.Architecture exposes GDB's internal representation
317 of architecture in the Python API.
319 ** New method Frame.architecture returns the gdb.Architecture object
320 corresponding to the frame's architecture.
322 * New Python-based convenience functions:
324 ** $_memeq(buf1, buf2, length)
325 ** $_streq(str1, str2)
327 ** $_regex(str, regex)
329 * The 'cd' command now defaults to using '~' (the home directory) if not
332 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
333 default for GCC since November 2000.
335 * The command 'forward-search' can now be abbreviated as 'fo'.
337 * The command 'info tracepoints' can now display 'installed on target'
338 or 'not installed on target' for each non-pending location of tracepoint.
340 * New configure options
342 --enable-libmcheck/--disable-libmcheck
343 By default, development versions are built with -lmcheck on hosts
344 that support it, in order to help track memory corruption issues.
345 Release versions, on the other hand, are built without -lmcheck
346 by default. The --enable-libmcheck/--disable-libmcheck configure
347 options allow the user to override that default.
348 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
349 This configure option allows the user to build GDB with
350 libbabeltrace using which GDB can read Common Trace Format data.
352 * New commands (for set/show, see "New options" below)
355 Catch signals. This is similar to "handle", but allows commands and
356 conditions to be attached.
359 List the BFDs known to GDB.
361 python-interactive [command]
363 Start a Python interactive prompt, or evaluate the optional command
364 and print the result of expressions.
367 "py" is a new alias for "python".
369 enable type-printer [name]...
370 disable type-printer [name]...
371 Enable or disable type printers.
375 ** For the Renesas Super-H architecture, the "regs" command has been removed
376 (has been deprecated in GDB 7.5), and "info all-registers" should be used
381 set print type methods (on|off)
382 show print type methods
383 Control whether method declarations are displayed by "ptype".
384 The default is to show them.
386 set print type typedefs (on|off)
387 show print type typedefs
388 Control whether typedef definitions are displayed by "ptype".
389 The default is to show them.
391 set filename-display basename|relative|absolute
392 show filename-display
393 Control the way in which filenames is displayed.
394 The default is "relative", which preserves previous behavior.
396 set trace-buffer-size
397 show trace-buffer-size
398 Request target to change the size of trace buffer.
400 set remote trace-buffer-size-packet auto|on|off
401 show remote trace-buffer-size-packet
402 Control the use of the remote protocol `QTBuffer:size' packet.
406 Control display of debugging messages related to ARM AArch64.
409 set debug coff-pe-read
410 show debug coff-pe-read
411 Control display of debugging messages related to reading of COFF/PE
416 Control display of debugging messages related to Mach-O symbols
419 set debug notification
420 show debug notification
421 Control display of debugging info for async remote notification.
425 ** Command parameter changes are now notified using new async record
426 "=cmd-param-changed".
427 ** Trace frame changes caused by command "tfind" are now notified using
428 new async record "=traceframe-changed".
429 ** The creation, deletion and modification of trace state variables
430 are now notified using new async records "=tsv-created",
431 "=tsv-deleted" and "=tsv-modified".
432 ** The start and stop of process record are now notified using new
433 async record "=record-started" and "=record-stopped".
434 ** Memory changes are now notified using new async record
436 ** The data-disassemble command response will include a "fullname" field
437 containing the absolute file name when source has been requested.
438 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
439 command, to allow pattern filling of memory areas.
440 ** New commands "-catch-load"/"-catch-unload" added for intercepting
441 library load/unload events.
442 ** The response to breakpoint commands and breakpoint async records
443 includes an "installed" field containing a boolean state about each
444 non-pending tracepoint location is whether installed on target or not.
445 ** Output of the "-trace-status" command includes a "trace-file" field
446 containing the name of the trace file being examined. This field is
447 optional, and only present when examining a trace file.
448 ** The "fullname" field is now always present along with the "file" field,
449 even if the file cannot be found by GDB.
451 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
452 You must have the LZMA library available when configuring GDB for this
453 feature to be enabled. For more information, see:
454 http://fedoraproject.org/wiki/Features/MiniDebugInfo
459 Set the size of trace buffer. The remote stub reports support for this
460 packet to gdb's qSupported query.
463 Enable Branch Trace Store (BTS)-based branch tracing for the current
464 thread. The remote stub reports support for this packet to gdb's
468 Disable branch tracing for the current thread. The remote stub reports
469 support for this packet to gdb's qSupported query.
472 Read the traced branches for the current thread. The remote stub
473 reports support for this packet to gdb's qSupported query.
475 *** Changes in GDB 7.5
477 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
478 for more x32 ABI info.
480 * GDB now supports access to MIPS DSP registers on Linux targets.
482 * GDB now supports debugging microMIPS binaries.
484 * The "info os" command on GNU/Linux can now display information on
485 several new classes of objects managed by the operating system:
486 "info os procgroups" lists process groups
487 "info os files" lists file descriptors
488 "info os sockets" lists internet-domain sockets
489 "info os shm" lists shared-memory regions
490 "info os semaphores" lists semaphores
491 "info os msg" lists message queues
492 "info os modules" lists loaded kernel modules
494 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
495 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
496 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
497 options and inspect the probe arguments using the new $_probe_arg family
498 of convenience variables. You can obtain more information about SystemTap
499 in <http://sourceware.org/systemtap/>.
501 * GDB now supports reversible debugging on ARM, it allows you to
502 debug basic ARM and THUMB instructions, and provides
503 record/replay support.
505 * The option "symbol-reloading" has been deleted as it is no longer used.
509 ** GDB commands implemented in Python can now be put in command class
512 ** The "maint set python print-stack on|off" is now deleted.
514 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
515 apply "flag enum"-style pretty-printing to any enum.
517 ** gdb.lookup_symbol can now work when there is no current frame.
519 ** gdb.Symbol now has a 'line' attribute, holding the line number in
520 the source at which the symbol was defined.
522 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
523 method 'value'. The former indicates whether the symbol needs a
524 frame in order to compute its value, and the latter computes the
527 ** A new method 'referenced_value' on gdb.Value objects which can
528 dereference pointer as well as C++ reference values.
530 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
531 which return the global and static blocks (as gdb.Block objects),
532 of the underlying symbol table, respectively.
534 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
535 object associated with a PC value.
537 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
538 of the address range occupied by code for the current source line.
540 * Go language support.
541 GDB now supports debugging programs written in the Go programming
544 * GDBserver now supports stdio connections.
545 E.g. (gdb) target remote | ssh myhost gdbserver - hello
547 * The binary "gdbtui" can no longer be built or installed.
548 Use "gdb -tui" instead.
550 * GDB will now print "flag" enums specially. A flag enum is one where
551 all the enumerator values have no bits in common when pairwise
552 "and"ed. When printing a value whose type is a flag enum, GDB will
553 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
554 (gdb) print (enum E) 3
557 * The filename part of a linespec will now match trailing components
558 of a source file name. For example, "break gcc/expr.c:1000" will
559 now set a breakpoint in build/gcc/expr.c, but not
562 * The "info proc" and "generate-core-file" commands will now also
563 work on remote targets connected to GDBserver on Linux.
565 * The command "info catch" has been removed. It has been disabled
568 * The "catch exception" and "catch assert" commands now accept
569 a condition at the end of the command, much like the "break"
570 command does. For instance:
572 (gdb) catch exception Constraint_Error if Barrier = True
574 Previously, it was possible to add a condition to such catchpoints,
575 but it had to be done as a second step, after the catchpoint had been
576 created, using the "condition" command.
578 * The "info static-tracepoint-marker" command will now also work on
579 native Linux targets with in-process agent.
581 * GDB can now set breakpoints on inlined functions.
583 * The .gdb_index section has been updated to include symbols for
584 inlined functions. GDB will ignore older .gdb_index sections by
585 default, which could cause symbol files to be loaded more slowly
586 until their .gdb_index sections can be recreated. The new command
587 "set use-deprecated-index-sections on" will cause GDB to use any older
588 .gdb_index sections it finds. This will restore performance, but the
589 ability to set breakpoints on inlined functions will be lost in symbol
590 files with older .gdb_index sections.
592 The .gdb_index section has also been updated to record more information
593 about each symbol. This speeds up the "info variables", "info functions"
594 and "info types" commands when used with programs having the .gdb_index
595 section, as well as speeding up debugging with shared libraries using
596 the .gdb_index section.
598 * Ada support for GDB/MI Variable Objects has been added.
600 * GDB can now support 'breakpoint always-inserted mode' in 'record'
605 ** New command -info-os is the MI equivalent of "info os".
607 ** Output logs ("set logging" and related) now include MI output.
611 ** "set use-deprecated-index-sections on|off"
612 "show use-deprecated-index-sections on|off"
613 Controls the use of deprecated .gdb_index sections.
615 ** "catch load" and "catch unload" can be used to stop when a shared
616 library is loaded or unloaded, respectively.
618 ** "enable count" can be used to auto-disable a breakpoint after
621 ** "info vtbl" can be used to show the virtual method tables for
622 C++ and Java objects.
624 ** "explore" and its sub commands "explore value" and "explore type"
625 can be used to reccursively explore values and types of
626 expressions. These commands are available only if GDB is
627 configured with '--with-python'.
629 ** "info auto-load" shows status of all kinds of auto-loaded files,
630 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
631 sequences of commands files, "info auto-load python-scripts"
632 shows status of auto-loading Python script files,
633 "info auto-load local-gdbinit" shows status of loading init file
634 (.gdbinit) from current directory and "info auto-load libthread-db" shows
635 status of inferior specific thread debugging shared library loading.
637 ** "info auto-load-scripts", "set auto-load-scripts on|off"
638 and "show auto-load-scripts" commands have been deprecated, use their
639 "info auto-load python-scripts", "set auto-load python-scripts on|off"
640 and "show auto-load python-scripts" counterparts instead.
642 ** "dprintf location,format,args..." creates a dynamic printf, which
643 is basically a breakpoint that does a printf and immediately
644 resumes your program's execution, so it is like a printf that you
645 can insert dynamically at runtime instead of at compiletime.
647 ** "set print symbol"
649 Controls whether GDB attempts to display the symbol, if any,
650 corresponding to addresses it prints. This defaults to "on", but
651 you can set it to "off" to restore GDB's previous behavior.
653 * Deprecated commands
655 ** For the Renesas Super-H architecture, the "regs" command has been
656 deprecated, and "info all-registers" should be used instead.
660 Renesas RL78 rl78-*-elf
661 HP OpenVMS ia64 ia64-hp-openvms*
663 * GDBserver supports evaluation of breakpoint conditions. When
664 support is advertised by GDBserver, GDB may be told to send the
665 breakpoint conditions in bytecode form to GDBserver. GDBserver
666 will only report the breakpoint trigger to GDB when its condition
672 show mips compression
673 Select the compressed ISA encoding used in functions that have no symbol
674 information available. The encoding can be set to either of:
677 and is updated automatically from ELF file flags if available.
679 set breakpoint condition-evaluation
680 show breakpoint condition-evaluation
681 Control whether breakpoint conditions are evaluated by GDB ("host") or by
682 GDBserver ("target"). Default option "auto" chooses the most efficient
684 This option can improve debugger efficiency depending on the speed of the
688 Disable auto-loading globally.
691 Show auto-loading setting of all kinds of auto-loaded files.
693 set auto-load gdb-scripts on|off
694 show auto-load gdb-scripts
695 Control auto-loading of GDB canned sequences of commands files.
697 set auto-load python-scripts on|off
698 show auto-load python-scripts
699 Control auto-loading of Python script files.
701 set auto-load local-gdbinit on|off
702 show auto-load local-gdbinit
703 Control loading of init file (.gdbinit) from current directory.
705 set auto-load libthread-db on|off
706 show auto-load libthread-db
707 Control auto-loading of inferior specific thread debugging shared library.
709 set auto-load scripts-directory <dir1>[:<dir2>...]
710 show auto-load scripts-directory
711 Set a list of directories from which to load auto-loaded scripts.
712 Automatically loaded Python scripts and GDB scripts are located in one
713 of the directories listed by this option.
714 The delimiter (':' above) may differ according to the host platform.
716 set auto-load safe-path <dir1>[:<dir2>...]
717 show auto-load safe-path
718 Set a list of directories from which it is safe to auto-load files.
719 The delimiter (':' above) may differ according to the host platform.
721 set debug auto-load on|off
723 Control display of debugging info for auto-loading the files above.
725 set dprintf-style gdb|call|agent
727 Control the way in which a dynamic printf is performed; "gdb"
728 requests a GDB printf command, while "call" causes dprintf to call a
729 function in the inferior. "agent" requests that the target agent
730 (such as GDBserver) do the printing.
732 set dprintf-function <expr>
733 show dprintf-function
734 set dprintf-channel <expr>
736 Set the function and optional first argument to the call when using
737 the "call" style of dynamic printf.
739 set disconnected-dprintf on|off
740 show disconnected-dprintf
741 Control whether agent-style dynamic printfs continue to be in effect
742 after GDB disconnects.
744 * New configure options
747 Configure default value for the 'set auto-load scripts-directory'
748 setting above. It defaults to '$debugdir:$datadir/auto-load',
749 $debugdir representing global debugging info directories (available
750 via 'show debug-file-directory') and $datadir representing GDB's data
751 directory (available via 'show data-directory').
753 --with-auto-load-safe-path
754 Configure default value for the 'set auto-load safe-path' setting
755 above. It defaults to the --with-auto-load-dir setting.
757 --without-auto-load-safe-path
758 Set 'set auto-load safe-path' to '/', effectively disabling this
763 z0/z1 conditional breakpoints extension
765 The z0/z1 breakpoint insertion packets have been extended to carry
766 a list of conditional expressions over to the remote stub depending on the
767 condition evaluation mode. The use of this extension can be controlled
768 via the "set remote conditional-breakpoints-packet" command.
772 Specify the signals which the remote stub may pass to the debugged
773 program without GDB involvement.
775 * New command line options
777 --init-command=FILE, -ix Like --command, -x but execute it
778 before loading inferior.
779 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
780 execute it before loading inferior.
782 *** Changes in GDB 7.4
784 * GDB now handles ambiguous linespecs more consistently; the existing
785 FILE:LINE support has been expanded to other types of linespecs. A
786 breakpoint will now be set on all matching locations in all
787 inferiors, and locations will be added or removed according to
790 * GDB now allows you to skip uninteresting functions and files when
791 stepping with the "skip function" and "skip file" commands.
793 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
794 and "show remote hardware-watchpoint-length-limit". These allows to
795 set or show the maximum length limit (in bytes) of a remote
796 target hardware watchpoint.
798 This allows e.g. to use "unlimited" hardware watchpoints with the
799 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
800 watchpoints are slower than real hardware watchpoints but are
801 significantly faster than gdb software watchpoints.
805 ** The register_pretty_printer function in module gdb.printing now takes
806 an optional `replace' argument. If True, the new printer replaces any
809 ** The "maint set python print-stack on|off" command has been
810 deprecated and will be deleted in GDB 7.5.
811 A new command: "set python print-stack none|full|message" has
812 replaced it. Additionally, the default for "print-stack" is
813 now "message", which just prints the error message without
816 ** A prompt substitution hook (prompt_hook) is now available to the
819 ** A new Python module, gdb.prompt has been added to the GDB Python
820 modules library. This module provides functionality for
821 escape sequences in prompts (used by set/show
822 extended-prompt). These escape sequences are replaced by their
825 ** Python commands and convenience-functions located in
826 'data-directory'/python/gdb/command and
827 'data-directory'/python/gdb/function are now automatically loaded
830 ** Blocks now provide four new attributes. global_block and
831 static_block will return the global and static blocks
832 respectively. is_static and is_global are boolean attributes
833 that indicate if the block is one of those two types.
835 ** Symbols now provide the "type" attribute, the type of the symbol.
837 ** The "gdb.breakpoint" function has been deprecated in favor of
840 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
841 of a function. This class is based on the "finish" command
842 available in the CLI.
844 ** Type objects for struct and union types now allow access to
845 the fields using standard Python dictionary (mapping) methods.
846 For example, "some_type['myfield']" now works, as does
849 ** A new event "gdb.new_objfile" has been added, triggered by loading a
852 ** A new function, "deep_items" has been added to the gdb.types
853 module in the GDB Python modules library. This function returns
854 an iterator over the fields of a struct or union type. Unlike
855 the standard Python "iteritems" method, it will recursively traverse
856 any anonymous fields.
860 ** "*stopped" events can report several new "reason"s, such as
863 ** Breakpoint changes are now notified using new async records, like
864 "=breakpoint-modified".
866 ** New command -ada-task-info.
868 * libthread-db-search-path now supports two special values: $sdir and $pdir.
869 $sdir specifies the default system locations of shared libraries.
870 $pdir specifies the directory where the libpthread used by the application
873 GDB no longer looks in $sdir and $pdir after it has searched the directories
874 mentioned in libthread-db-search-path. If you want to search those
875 directories, they must be specified in libthread-db-search-path.
876 The default value of libthread-db-search-path on GNU/Linux and Solaris
877 systems is now "$sdir:$pdir".
879 $pdir is not supported by gdbserver, it is currently ignored.
880 $sdir is supported by gdbserver.
882 * New configure option --with-iconv-bin.
883 When using the internationalization support like the one in the GNU C
884 library, GDB will invoke the "iconv" program to get a list of supported
885 character sets. If this program lives in a non-standard location, one can
886 use this option to specify where to find it.
888 * When natively debugging programs on PowerPC BookE processors running
889 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
890 watchpoints, which specify a mask in addition to an address to watch.
891 The mask specifies that some bits of an address (the bits which are
892 reset in the mask) should be ignored when matching the address accessed
893 by the inferior against the watchpoint address. See the "PowerPC Embedded"
894 section in the user manual for more details.
896 * The new option --once causes GDBserver to stop listening for connections once
897 the first connection is made. The listening port used by GDBserver will
898 become available after that.
900 * New commands "info macros" and "alias" have been added.
902 * New function parameters suffix @entry specifies value of function parameter
903 at the time the function got called. Entry values are available only since
909 "!" is now an alias of the "shell" command.
910 Note that no space is needed between "!" and SHELL COMMAND.
914 watch EXPRESSION mask MASK_VALUE
915 The watch command now supports the mask argument which allows creation
916 of masked watchpoints, if the current architecture supports this feature.
918 info auto-load-scripts [REGEXP]
919 This command was formerly named "maintenance print section-scripts".
920 It is now generally useful and is no longer a maintenance-only command.
922 info macro [-all] [--] MACRO
923 The info macro command has new options `-all' and `--'. The first for
924 printing all definitions of a macro. The second for explicitly specifying
925 the end of arguments and the beginning of the macro name in case the macro
926 name starts with a hyphen.
928 collect[/s] EXPRESSIONS
929 The tracepoint collect command now takes an optional modifier "/s"
930 that directs it to dereference pointer-to-character types and
931 collect the bytes of memory up to a zero byte. The behavior is
932 similar to what you see when you use the regular print command on a
933 string. An optional integer following the "/s" sets a bound on the
934 number of bytes that will be collected.
937 The trace start command now interprets any supplied arguments as a
938 note to be recorded with the trace run, with an effect similar to
939 setting the variable trace-notes.
942 The trace stop command now interprets any arguments as a note to be
943 mentioned along with the tstatus report that the trace was stopped
944 with a command. The effect is similar to setting the variable
947 * Tracepoints can now be enabled and disabled at any time after a trace
948 experiment has been started using the standard "enable" and "disable"
949 commands. It is now possible to start a trace experiment with no enabled
950 tracepoints; GDB will display a warning, but will allow the experiment to
951 begin, assuming that tracepoints will be enabled as needed while the trace
954 * Fast tracepoints on 32-bit x86-architectures can now be placed at
955 locations with 4-byte instructions, when they were previously
956 limited to locations with instructions of 5 bytes or longer.
960 set debug dwarf2-read
961 show debug dwarf2-read
962 Turns on or off display of debugging messages related to reading
963 DWARF debug info. The default is off.
965 set debug symtab-create
966 show debug symtab-create
967 Turns on or off display of debugging messages related to symbol table
968 creation. The default is off.
972 Set the GDB prompt, and allow escape sequences to be inserted to
973 display miscellaneous information (see 'help set extended-prompt'
974 for the list of sequences). This prompt (and any information
975 accessed through the escape sequences) is updated every time the
978 set print entry-values (both|compact|default|if-needed|no|only|preferred)
979 show print entry-values
980 Set printing of frame argument values at function entry. In some cases
981 GDB can determine the value of function argument which was passed by the
982 function caller, even if the value was modified inside the called function.
984 set debug entry-values
985 show debug entry-values
986 Control display of debugging info for determining frame argument values at
987 function entry and virtual tail call frames.
989 set basenames-may-differ
990 show basenames-may-differ
991 Set whether a source file may have multiple base names.
992 (A "base name" is the name of a file with the directory part removed.
993 Example: The base name of "/home/user/hello.c" is "hello.c".)
994 If set, GDB will canonicalize file names (e.g., expand symlinks)
995 before comparing them. Canonicalization is an expensive operation,
996 but it allows the same file be known by more than one base name.
997 If not set (the default), all source files are assumed to have just
998 one base name, and gdb will do file name comparisons more efficiently.
1004 Set a user name and notes for the current and any future trace runs.
1005 This is useful for long-running and/or disconnected traces, to
1006 inform others (or yourself) as to who is running the trace, supply
1007 contact information, or otherwise explain what is going on.
1009 set trace-stop-notes
1010 show trace-stop-notes
1011 Set a note attached to the trace run, that is displayed when the
1012 trace has been stopped by a tstop command. This is useful for
1013 instance as an explanation, if you are stopping a trace run that was
1014 started by someone else.
1016 * New remote packets
1020 Dynamically enable a tracepoint in a started trace experiment.
1024 Dynamically disable a tracepoint in a started trace experiment.
1028 Set the user and notes of the trace run.
1032 Query the current status of a tracepoint.
1036 Query the minimum length of instruction at which a fast tracepoint may
1039 * Dcache size (number of lines) and line-size are now runtime-configurable
1040 via "set dcache line" and "set dcache line-size" commands.
1044 Texas Instruments TMS320C6x tic6x-*-*
1048 Renesas RL78 rl78-*-elf
1050 *** Changes in GDB 7.3.1
1052 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1054 *** Changes in GDB 7.3
1056 * GDB has a new command: "thread find [REGEXP]".
1057 It finds the thread id whose name, target id, or thread extra info
1058 matches the given regular expression.
1060 * The "catch syscall" command now works on mips*-linux* targets.
1062 * The -data-disassemble MI command now supports modes 2 and 3 for
1063 dumping the instruction opcodes.
1065 * New command line options
1067 -data-directory DIR Specify DIR as the "data-directory".
1068 This is mostly for testing purposes.
1070 * The "maint set python auto-load on|off" command has been renamed to
1071 "set auto-load-scripts on|off".
1073 * GDB has a new command: "set directories".
1074 It is like the "dir" command except that it replaces the
1075 source path list instead of augmenting it.
1077 * GDB now understands thread names.
1079 On GNU/Linux, "info threads" will display the thread name as set by
1080 prctl or pthread_setname_np.
1082 There is also a new command, "thread name", which can be used to
1083 assign a name internally for GDB to display.
1086 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1087 has been integrated into GDB.
1091 ** The function gdb.Write now accepts an optional keyword 'stream'.
1092 This keyword, when provided, will direct the output to either
1093 stdout, stderr, or GDB's logging output.
1095 ** Parameters can now be be sub-classed in Python, and in particular
1096 you may implement the get_set_doc and get_show_doc functions.
1097 This improves how Parameter set/show documentation is processed
1098 and allows for more dynamic content.
1100 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1101 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1102 have an is_valid method.
1104 ** Breakpoints can now be sub-classed in Python, and in particular
1105 you may implement a 'stop' function that is executed each time
1106 the inferior reaches that breakpoint.
1108 ** New function gdb.lookup_global_symbol looks up a global symbol.
1110 ** GDB values in Python are now callable if the value represents a
1111 function. For example, if 'some_value' represents a function that
1112 takes two integer parameters and returns a value, you can call
1113 that function like so:
1115 result = some_value (10,20)
1117 ** Module gdb.types has been added.
1118 It contains a collection of utilities for working with gdb.Types objects:
1119 get_basic_type, has_field, make_enum_dict.
1121 ** Module gdb.printing has been added.
1122 It contains utilities for writing and registering pretty-printers.
1123 New classes: PrettyPrinter, SubPrettyPrinter,
1124 RegexpCollectionPrettyPrinter.
1125 New function: register_pretty_printer.
1127 ** New commands "info pretty-printers", "enable pretty-printer" and
1128 "disable pretty-printer" have been added.
1130 ** gdb.parameter("directories") is now available.
1132 ** New function gdb.newest_frame returns the newest frame in the
1135 ** The gdb.InferiorThread class has a new "name" attribute. This
1136 holds the thread's name.
1138 ** Python Support for Inferior events.
1139 Python scripts can add observers to be notified of events
1140 occurring in the process being debugged.
1141 The following events are currently supported:
1142 - gdb.events.cont Continue event.
1143 - gdb.events.exited Inferior exited event.
1144 - gdb.events.stop Signal received, and Breakpoint hit events.
1148 ** GDB now puts template parameters in scope when debugging in an
1149 instantiation. For example, if you have:
1151 template<int X> int func (void) { return X; }
1153 then if you step into func<5>, "print X" will show "5". This
1154 feature requires proper debuginfo support from the compiler; it
1155 was added to GCC 4.5.
1157 ** The motion commands "next", "finish", "until", and "advance" now
1158 work better when exceptions are thrown. In particular, GDB will
1159 no longer lose control of the inferior; instead, the GDB will
1160 stop the inferior at the point at which the exception is caught.
1161 This functionality requires a change in the exception handling
1162 code that was introduced in GCC 4.5.
1164 * GDB now follows GCC's rules on accessing volatile objects when
1165 reading or writing target state during expression evaluation.
1166 One notable difference to prior behavior is that "print x = 0"
1167 no longer generates a read of x; the value of the assignment is
1168 now always taken directly from the value being assigned.
1170 * GDB now has some support for using labels in the program's source in
1171 linespecs. For instance, you can use "advance label" to continue
1172 execution to a label.
1174 * GDB now has support for reading and writing a new .gdb_index
1175 section. This section holds a fast index of DWARF debugging
1176 information and can be used to greatly speed up GDB startup and
1177 operation. See the documentation for `save gdb-index' for details.
1179 * The "watch" command now accepts an optional "-location" argument.
1180 When used, this causes GDB to watch the memory referred to by the
1181 expression. Such a watchpoint is never deleted due to it going out
1184 * GDB now supports thread debugging of core dumps on GNU/Linux.
1186 GDB now activates thread debugging using the libthread_db library
1187 when debugging GNU/Linux core dumps, similarly to when debugging
1188 live processes. As a result, when debugging a core dump file, GDB
1189 is now able to display pthread_t ids of threads. For example, "info
1190 threads" shows the same output as when debugging the process when it
1191 was live. In earlier releases, you'd see something like this:
1194 * 1 LWP 6780 main () at main.c:10
1196 While now you see this:
1199 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1201 It is also now possible to inspect TLS variables when debugging core
1204 When debugging a core dump generated on a machine other than the one
1205 used to run GDB, you may need to point GDB at the correct
1206 libthread_db library with the "set libthread-db-search-path"
1207 command. See the user manual for more details on this command.
1209 * When natively debugging programs on PowerPC BookE processors running
1210 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1211 which stop execution of the inferior whenever it executes an instruction
1212 at any address within the specified range. See the "PowerPC Embedded"
1213 section in the user manual for more details.
1215 * New features in the GDB remote stub, GDBserver
1217 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1218 and i686 LynxOS (version 5.x).
1220 ** GDBserver is now supported on Blackfin Linux.
1222 * New native configurations
1224 ia64 HP-UX ia64-*-hpux*
1228 Analog Devices, Inc. Blackfin Processor bfin-*
1230 * Ada task switching is now supported on sparc-elf targets when
1231 debugging a program using the Ravenscar Profile. For more information,
1232 see the "Tasking Support when using the Ravenscar Profile" section
1233 in the GDB user manual.
1235 * Guile support was removed.
1237 * New features in the GNU simulator
1239 ** The --map-info flag lists all known core mappings.
1241 ** CFI flashes may be simulated via the "cfi" device.
1243 *** Changes in GDB 7.2
1245 * Shared library support for remote targets by default
1247 When GDB is configured for a generic, non-OS specific target, like
1248 for example, --target=arm-eabi or one of the many *-*-elf targets,
1249 GDB now queries remote stubs for loaded shared libraries using the
1250 `qXfer:libraries:read' packet. Previously, shared library support
1251 was always disabled for such configurations.
1255 ** Argument Dependent Lookup (ADL)
1257 In C++ ADL lookup directs function search to the namespaces of its
1258 arguments even if the namespace has not been imported.
1268 Here the compiler will search for `foo' in the namespace of 'b'
1269 and find A::foo. GDB now supports this. This construct is commonly
1270 used in the Standard Template Library for operators.
1272 ** Improved User Defined Operator Support
1274 In addition to member operators, GDB now supports lookup of operators
1275 defined in a namespace and imported with a `using' directive, operators
1276 defined in the global scope, operators imported implicitly from an
1277 anonymous namespace, and the ADL operators mentioned in the previous
1279 GDB now also supports proper overload resolution for all the previously
1280 mentioned flavors of operators.
1282 ** static const class members
1284 Printing of static const class members that are initialized in the
1285 class definition has been fixed.
1287 * Windows Thread Information Block access.
1289 On Windows targets, GDB now supports displaying the Windows Thread
1290 Information Block (TIB) structure. This structure is visible either
1291 by using the new command `info w32 thread-information-block' or, by
1292 dereferencing the new convenience variable named `$_tlb', a
1293 thread-specific pointer to the TIB. This feature is also supported
1294 when remote debugging using GDBserver.
1296 * Static tracepoints
1298 Static tracepoints are calls in the user program into a tracing
1299 library. One such library is a port of the LTTng kernel tracer to
1300 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1301 When debugging with GDBserver, GDB now supports combining the GDB
1302 tracepoint machinery with such libraries. For example: the user can
1303 use GDB to probe a static tracepoint marker (a call from the user
1304 program into the tracing library) with the new "strace" command (see
1305 "New commands" below). This creates a "static tracepoint" in the
1306 breakpoint list, that can be manipulated with the same feature set
1307 as fast and regular tracepoints. E.g., collect registers, local and
1308 global variables, collect trace state variables, and define
1309 tracepoint conditions. In addition, the user can collect extra
1310 static tracepoint marker specific data, by collecting the new
1311 $_sdata internal variable. When analyzing the trace buffer, you can
1312 inspect $_sdata like any other variable available to GDB. For more
1313 information, see the "Tracepoints" chapter in GDB user manual. New
1314 remote packets have been defined to support static tracepoints, see
1315 the "New remote packets" section below.
1317 * Better reconstruction of tracepoints after disconnected tracing
1319 GDB will attempt to download the original source form of tracepoint
1320 definitions when starting a trace run, and then will upload these
1321 upon reconnection to the target, resulting in a more accurate
1322 reconstruction of the tracepoints that are in use on the target.
1326 You can now exercise direct control over the ways that GDB can
1327 affect your program. For instance, you can disallow the setting of
1328 breakpoints, so that the program can run continuously (assuming
1329 non-stop mode). In addition, the "observer" variable is available
1330 to switch all of the different controls; in observer mode, GDB
1331 cannot affect the target's behavior at all, which is useful for
1332 tasks like diagnosing live systems in the field.
1334 * The new convenience variable $_thread holds the number of the
1337 * New remote packets
1341 Return the address of the Windows Thread Information Block of a given thread.
1345 In response to several of the tracepoint packets, the target may now
1346 also respond with a number of intermediate `qRelocInsn' request
1347 packets before the final result packet, to have GDB handle
1348 relocating an instruction to execute at a different address. This
1349 is particularly useful for stubs that support fast tracepoints. GDB
1350 reports support for this feature in the qSupported packet.
1354 List static tracepoint markers in the target program.
1358 List static tracepoint markers at a given address in the target
1361 qXfer:statictrace:read
1363 Read the static trace data collected (by a `collect $_sdata'
1364 tracepoint action). The remote stub reports support for this packet
1365 to gdb's qSupported query.
1369 Send the current settings of GDB's permission flags.
1373 Send part of the source (textual) form of a tracepoint definition,
1374 which includes location, conditional, and action list.
1376 * The source command now accepts a -s option to force searching for the
1377 script in the source search path even if the script name specifies
1380 * New features in the GDB remote stub, GDBserver
1382 - GDBserver now support tracepoints (including fast tracepoints, and
1383 static tracepoints). The feature is currently supported by the
1384 i386-linux and amd64-linux builds. See the "Tracepoints support
1385 in gdbserver" section in the manual for more information.
1387 GDBserver JIT compiles the tracepoint's conditional agent
1388 expression bytecode into native code whenever possible for low
1389 overhead dynamic tracepoints conditionals. For such tracepoints,
1390 an expression that examines program state is evaluated when the
1391 tracepoint is reached, in order to determine whether to capture
1392 trace data. If the condition is simple and false, processing the
1393 tracepoint finishes very quickly and no data is gathered.
1395 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1396 for static tracepoints support.
1398 - GDBserver now supports x86_64 Windows 64-bit debugging.
1400 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1401 it understands register description.
1403 * The --batch flag now disables pagination and queries.
1405 * X86 general purpose registers
1407 GDB now supports reading/writing byte, word and double-word x86
1408 general purpose registers directly. This means you can use, say,
1409 $ah or $ax to refer, respectively, to the byte register AH and
1410 16-bit word register AX that are actually portions of the 32-bit
1411 register EAX or 64-bit register RAX.
1413 * The `commands' command now accepts a range of breakpoints to modify.
1414 A plain `commands' following a command that creates multiple
1415 breakpoints affects all the breakpoints set by that command. This
1416 applies to breakpoints set by `rbreak', and also applies when a
1417 single `break' command creates multiple breakpoints (e.g.,
1418 breakpoints on overloaded c++ functions).
1420 * The `rbreak' command now accepts a filename specification as part of
1421 its argument, limiting the functions selected by the regex to those
1422 in the specified file.
1424 * Support for remote debugging Windows and SymbianOS shared libraries
1425 from Unix hosts has been improved. Non Windows GDB builds now can
1426 understand target reported file names that follow MS-DOS based file
1427 system semantics, such as file names that include drive letters and
1428 use the backslash character as directory separator. This makes it
1429 possible to transparently use the "set sysroot" and "set
1430 solib-search-path" on Unix hosts to point as host copies of the
1431 target's shared libraries. See the new command "set
1432 target-file-system-kind" described below, and the "Commands to
1433 specify files" section in the user manual for more information.
1437 eval template, expressions...
1438 Convert the values of one or more expressions under the control
1439 of the string template to a command line, and call it.
1441 set target-file-system-kind unix|dos-based|auto
1442 show target-file-system-kind
1443 Set or show the assumed file system kind for target reported file
1446 save breakpoints <filename>
1447 Save all current breakpoint definitions to a file suitable for use
1448 in a later debugging session. To read the saved breakpoint
1449 definitions, use the `source' command.
1451 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1454 info static-tracepoint-markers
1455 Display information about static tracepoint markers in the target.
1457 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1458 Define a static tracepoint by probing a marker at the given
1459 function, line, address, or marker ID.
1463 Enable and disable observer mode.
1465 set may-write-registers on|off
1466 set may-write-memory on|off
1467 set may-insert-breakpoints on|off
1468 set may-insert-tracepoints on|off
1469 set may-insert-fast-tracepoints on|off
1470 set may-interrupt on|off
1471 Set individual permissions for GDB effects on the target. Note that
1472 some of these settings can have undesirable or surprising
1473 consequences, particularly when changed in the middle of a session.
1474 For instance, disabling the writing of memory can prevent
1475 breakpoints from being inserted, cause single-stepping to fail, or
1476 even crash your program, if you disable after breakpoints have been
1477 inserted. However, GDB should not crash.
1479 set record memory-query on|off
1480 show record memory-query
1481 Control whether to stop the inferior if memory changes caused
1482 by an instruction cannot be recorded.
1487 The disassemble command now supports "start,+length" form of two arguments.
1491 ** GDB now provides a new directory location, called the python directory,
1492 where Python scripts written for GDB can be installed. The location
1493 of that directory is <data-directory>/python, where <data-directory>
1494 is the GDB data directory. For more details, see section `Scripting
1495 GDB using Python' in the manual.
1497 ** The GDB Python API now has access to breakpoints, symbols, symbol
1498 tables, program spaces, inferiors, threads and frame's code blocks.
1499 Additionally, GDB Parameters can now be created from the API, and
1500 manipulated via set/show in the CLI.
1502 ** New functions gdb.target_charset, gdb.target_wide_charset,
1503 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1505 ** New exception gdb.GdbError.
1507 ** Pretty-printers are now also looked up in the current program space.
1509 ** Pretty-printers can now be individually enabled and disabled.
1511 ** GDB now looks for names of Python scripts to auto-load in a
1512 special section named `.debug_gdb_scripts', in addition to looking
1513 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1515 * Tracepoint actions were unified with breakpoint commands. In particular,
1516 there are no longer differences in "info break" output for breakpoints and
1517 tracepoints and the "commands" command can be used for both tracepoints and
1518 regular breakpoints.
1522 ARM Symbian arm*-*-symbianelf*
1524 * D language support.
1525 GDB now supports debugging programs written in the D programming
1528 * GDB now supports the extended ptrace interface for PowerPC which is
1529 available since Linux kernel version 2.6.34. This automatically enables
1530 any hardware breakpoints and additional hardware watchpoints available in
1531 the processor. The old ptrace interface exposes just one hardware
1532 watchpoint and no hardware breakpoints.
1534 * GDB is now able to use the Data Value Compare (DVC) register available on
1535 embedded PowerPC processors to implement in hardware simple watchpoint
1536 conditions of the form:
1538 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1540 This works in native GDB running on Linux kernels with the extended ptrace
1541 interface mentioned above.
1543 *** Changes in GDB 7.1
1547 ** Namespace Support
1549 GDB now supports importing of namespaces in C++. This enables the
1550 user to inspect variables from imported namespaces. Support for
1551 namepace aliasing has also been added. So, if a namespace is
1552 aliased in the current scope (e.g. namepace C=A; ) the user can
1553 print variables using the alias (e.g. (gdb) print C::x).
1557 All known bugs relating to the printing of virtual base class were
1558 fixed. It is now possible to call overloaded static methods using a
1563 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1564 and reinterpret_cast<> are now handled by the C++ expression parser.
1568 Xilinx MicroBlaze microblaze-*-*
1573 Xilinx MicroBlaze microblaze
1576 * Multi-program debugging.
1578 GDB now has support for multi-program (a.k.a. multi-executable or
1579 multi-exec) debugging. This allows for debugging multiple inferiors
1580 simultaneously each running a different program under the same GDB
1581 session. See "Debugging Multiple Inferiors and Programs" in the
1582 manual for more information. This implied some user visible changes
1583 in the multi-inferior support. For example, "info inferiors" now
1584 lists inferiors that are not running yet or that have exited
1585 already. See also "New commands" and "New options" below.
1587 * New tracing features
1589 GDB's tracepoint facility now includes several new features:
1591 ** Trace state variables
1593 GDB tracepoints now include support for trace state variables, which
1594 are variables managed by the target agent during a tracing
1595 experiment. They are useful for tracepoints that trigger each
1596 other, so for instance one tracepoint can count hits in a variable,
1597 and then a second tracepoint has a condition that is true when the
1598 count reaches a particular value. Trace state variables share the
1599 $-syntax of GDB convenience variables, and can appear in both
1600 tracepoint actions and condition expressions. Use the "tvariable"
1601 command to create, and "info tvariables" to view; see "Trace State
1602 Variables" in the manual for more detail.
1606 GDB now includes an option for defining fast tracepoints, which
1607 targets may implement more efficiently, such as by installing a jump
1608 into the target agent rather than a trap instruction. The resulting
1609 speedup can be by two orders of magnitude or more, although the
1610 tradeoff is that some program locations on some target architectures
1611 might not allow fast tracepoint installation, for instance if the
1612 instruction to be replaced is shorter than the jump. To request a
1613 fast tracepoint, use the "ftrace" command, with syntax identical to
1614 the regular trace command.
1616 ** Disconnected tracing
1618 It is now possible to detach GDB from the target while it is running
1619 a trace experiment, then reconnect later to see how the experiment
1620 is going. In addition, a new variable disconnected-tracing lets you
1621 tell the target agent whether to continue running a trace if the
1622 connection is lost unexpectedly.
1626 GDB now has the ability to save the trace buffer into a file, and
1627 then use that file as a target, similarly to you can do with
1628 corefiles. You can select trace frames, print data that was
1629 collected in them, and use tstatus to display the state of the
1630 tracing run at the moment that it was saved. To create a trace
1631 file, use "tsave <filename>", and to use it, do "target tfile
1634 ** Circular trace buffer
1636 You can ask the target agent to handle the trace buffer as a
1637 circular buffer, discarding the oldest trace frames to make room for
1638 newer ones, by setting circular-trace-buffer to on. This feature may
1639 not be available for all target agents.
1644 The disassemble command, when invoked with two arguments, now requires
1645 the arguments to be comma-separated.
1648 The info variables command now displays variable definitions. Files
1649 which only declare a variable are not shown.
1652 The source command is now capable of sourcing Python scripts.
1653 This feature is dependent on the debugger being build with Python
1656 Related to this enhancement is also the introduction of a new command
1657 "set script-extension" (see below).
1659 * New commands (for set/show, see "New options" below)
1661 record save [<FILENAME>]
1662 Save a file (in core file format) containing the process record
1663 execution log for replay debugging at a later time.
1665 record restore <FILENAME>
1666 Restore the process record execution log that was saved at an
1667 earlier time, for replay debugging.
1669 add-inferior [-copies <N>] [-exec <FILENAME>]
1672 clone-inferior [-copies <N>] [ID]
1673 Make a new inferior ready to execute the same program another
1674 inferior has loaded.
1679 maint info program-spaces
1680 List the program spaces loaded into GDB.
1682 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1683 show remote interrupt-sequence
1684 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1685 as the sequence to the remote target in order to interrupt the execution.
1686 Ctrl-C is a default. Some system prefers BREAK which is high level of
1687 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1688 Magic SysRq g. It is BREAK signal and character 'g'.
1690 set remote interrupt-on-connect [on | off]
1691 show remote interrupt-on-connect
1692 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1693 remote target when gdb connects to it. This is needed when you debug
1696 set remotebreak [on | off]
1698 Deprecated. Use "set/show remote interrupt-sequence" instead.
1700 tvariable $NAME [ = EXP ]
1701 Create or modify a trace state variable.
1704 List trace state variables and their values.
1706 delete tvariable $NAME ...
1707 Delete one or more trace state variables.
1710 Evaluate the given expressions without collecting anything into the
1711 trace buffer. (Valid in tracepoint actions only.)
1713 ftrace FN / FILE:LINE / *ADDR
1714 Define a fast tracepoint at the given function, line, or address.
1716 * New expression syntax
1718 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1719 GDB now parses 0b101010 identically with 42.
1723 set follow-exec-mode new|same
1724 show follow-exec-mode
1725 Control whether GDB reuses the same inferior across an exec call or
1726 creates a new one. This is useful to be able to restart the old
1727 executable after the inferior having done an exec call.
1729 set default-collect EXPR, ...
1730 show default-collect
1731 Define a list of expressions to be collected at each tracepoint.
1732 This is a useful way to ensure essential items are not overlooked,
1733 such as registers or a critical global variable.
1735 set disconnected-tracing
1736 show disconnected-tracing
1737 If set to 1, the target is instructed to continue tracing if it
1738 loses its connection to GDB. If 0, the target is to stop tracing
1741 set circular-trace-buffer
1742 show circular-trace-buffer
1743 If set to on, the target is instructed to use a circular trace buffer
1744 and discard the oldest trace frames instead of stopping the trace due
1745 to a full trace buffer. If set to off, the trace stops when the buffer
1746 fills up. Some targets may not support this.
1748 set script-extension off|soft|strict
1749 show script-extension
1750 If set to "off", the debugger does not perform any script language
1751 recognition, and all sourced files are assumed to be GDB scripts.
1752 If set to "soft" (the default), files are sourced according to
1753 filename extension, falling back to GDB scripts if the first
1755 If set to "strict", files are sourced according to filename extension.
1757 set ada trust-PAD-over-XVS on|off
1758 show ada trust-PAD-over-XVS
1759 If off, activate a workaround against a bug in the debugging information
1760 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1761 the GCC sources for more information about the GNAT encoding and
1762 PAD types in particular). It is always safe to set this option to
1763 off, but this introduces a slight performance penalty. The default
1766 * Python API Improvements
1768 ** GDB provides the new class gdb.LazyString. This is useful in
1769 some pretty-printing cases. The new method gdb.Value.lazy_string
1770 provides a simple way to create objects of this type.
1772 ** The fields returned by gdb.Type.fields now have an
1773 `is_base_class' attribute.
1775 ** The new method gdb.Type.range returns the range of an array type.
1777 ** The new method gdb.parse_and_eval can be used to parse and
1778 evaluate an expression.
1780 * New remote packets
1783 Define a trace state variable.
1786 Get the current value of a trace state variable.
1789 Set desired tracing behavior upon disconnection.
1792 Set the trace buffer to be linear or circular.
1795 Get data about the tracepoints currently in use.
1799 Process record now works correctly with hardware watchpoints.
1801 Multiple bug fixes have been made to the mips-irix port, making it
1802 much more reliable. In particular:
1803 - Debugging threaded applications is now possible again. Previously,
1804 GDB would hang while starting the program, or while waiting for
1805 the program to stop at a breakpoint.
1806 - Attaching to a running process no longer hangs.
1807 - An error occurring while loading a core file has been fixed.
1808 - Changing the value of the PC register now works again. This fixes
1809 problems observed when using the "jump" command, or when calling
1810 a function from GDB, or even when assigning a new value to $pc.
1811 - With the "finish" and "return" commands, the return value for functions
1812 returning a small array is now correctly printed.
1813 - It is now possible to break on shared library code which gets executed
1814 during a shared library init phase (code executed while executing
1815 their .init section). Previously, the breakpoint would have no effect.
1816 - GDB is now able to backtrace through the signal handler for
1817 non-threaded programs.
1819 PIE (Position Independent Executable) programs debugging is now supported.
1820 This includes debugging execution of PIC (Position Independent Code) shared
1821 libraries although for that, it should be possible to run such libraries as an
1824 *** Changes in GDB 7.0
1826 * GDB now has an interface for JIT compilation. Applications that
1827 dynamically generate code can create symbol files in memory and register
1828 them with GDB. For users, the feature should work transparently, and
1829 for JIT developers, the interface is documented in the GDB manual in the
1830 "JIT Compilation Interface" chapter.
1832 * Tracepoints may now be conditional. The syntax is as for
1833 breakpoints; either an "if" clause appended to the "trace" command,
1834 or the "condition" command is available. GDB sends the condition to
1835 the target for evaluation using the same bytecode format as is used
1836 for tracepoint actions.
1838 * The disassemble command now supports: an optional /r modifier, print the
1839 raw instructions in hex as well as in symbolic form, and an optional /m
1840 modifier to print mixed source+assembly.
1842 * Process record and replay
1844 In a architecture environment that supports ``process record and
1845 replay'', ``process record and replay'' target can record a log of
1846 the process execution, and replay it with both forward and reverse
1849 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1850 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1851 set execution-direction {forward|reverse}, for targets that support
1854 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1855 feature is available with a native GDB running on kernel version
1858 * GDB now has support for multi-byte and wide character sets on the
1859 target. Strings whose character type is wchar_t, char16_t, or
1860 char32_t are now correctly printed. GDB supports wide- and unicode-
1861 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1862 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1863 `printf'. This feature requires iconv to work properly; if your
1864 system does not have a working iconv, GDB can use GNU libiconv. See
1865 the installation instructions for more information.
1867 * GDB now supports automatic retrieval of shared library files from
1868 remote targets. To use this feature, specify a system root that begins
1869 with the `remote:' prefix, either via the `set sysroot' command or via
1870 the `--with-sysroot' configure-time option.
1872 * "info sharedlibrary" now takes an optional regex of libraries to show,
1873 and it now reports if a shared library has no debugging information.
1875 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1876 now complete on file names.
1878 * When completing in expressions, gdb will attempt to limit
1879 completions to allowable structure or union fields, where appropriate.
1880 For instance, consider:
1882 # struct example { int f1; double f2; };
1883 # struct example variable;
1886 If the user types TAB at the end of this command line, the available
1887 completions will be "f1" and "f2".
1889 * Inlined functions are now supported. They show up in backtraces, and
1890 the "step", "next", and "finish" commands handle them automatically.
1892 * GDB now supports the token-splicing (##) and stringification (#)
1893 operators when expanding macros. It also supports variable-arity
1896 * GDB now supports inspecting extra signal information, exported by
1897 the new $_siginfo convenience variable. The feature is currently
1898 implemented on linux ARM, i386 and amd64.
1900 * GDB can now display the VFP floating point registers and NEON vector
1901 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1902 can provide these registers (requires Linux 2.6.30 or later). Remote
1903 and simulator targets may also provide them.
1905 * New remote packets
1908 Search memory for a sequence of bytes.
1911 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1912 operation over reliable transport links. Use of this packet is
1913 controlled by the `set remote noack-packet' command.
1916 Kill the process with the specified process ID. Use this in preference
1917 to `k' when multiprocess protocol extensions are supported.
1920 Obtains additional operating system information
1924 Read or write additional signal information.
1926 * Removed remote protocol undocumented extension
1928 An undocumented extension to the remote protocol's `S' stop reply
1929 packet that permited the stub to pass a process id was removed.
1930 Remote servers should use the `T' stop reply packet instead.
1932 * GDB now supports multiple function calling conventions according to the
1933 DWARF-2 DW_AT_calling_convention function attribute.
1935 * The SH target utilizes the aforementioned change to distinguish between gcc
1936 and Renesas calling convention. It also adds the new CLI commands
1937 `set/show sh calling-convention'.
1939 * GDB can now read compressed debug sections, as produced by GNU gold
1940 with the --compress-debug-sections=zlib flag.
1942 * 64-bit core files are now supported on AIX.
1944 * Thread switching is now supported on Tru64.
1946 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1947 which will be allocated using malloc later in program execution.
1949 * The qXfer:libraries:read remote procotol packet now allows passing a
1950 list of section offsets.
1952 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1953 conditions handling signals delivered during attach or thread creation
1954 have also been fixed.
1956 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1957 From the user's standpoint, all unqualified instances of True and False
1958 are treated as the standard definitions, regardless of context.
1960 * GDB now parses C++ symbol and type names more flexibly. For
1963 template<typename T> class C { };
1966 GDB will now correctly handle all of:
1968 ptype C<char const *>
1969 ptype C<char const*>
1970 ptype C<const char *>
1971 ptype C<const char*>
1973 * New features in the GDB remote stub, gdbserver
1975 - The "--wrapper" command-line argument tells gdbserver to use a
1976 wrapper program to launch programs for debugging.
1978 - On PowerPC and S/390 targets, it is now possible to use a single
1979 gdbserver executable to debug both 32-bit and 64-bit programs.
1980 (This requires gdbserver itself to be built as a 64-bit executable.)
1982 - gdbserver uses the new noack protocol mode for TCP connections to
1983 reduce communications latency, if also supported and enabled in GDB.
1985 - Support for the sparc64-linux-gnu target is now included in
1988 - The amd64-linux build of gdbserver now supports debugging both
1989 32-bit and 64-bit programs.
1991 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1992 now support hardware watchpoints, and will use them automatically
1997 GDB now has support for scripting using Python. Whether this is
1998 available is determined at configure time.
2000 New GDB commands can now be written in Python.
2002 * Ada tasking support
2004 Ada tasks can now be inspected in GDB. The following commands have
2008 Print the list of Ada tasks.
2010 Print detailed information about task number N.
2012 Print the task number of the current task.
2014 Switch the context of debugging to task number N.
2016 * Support for user-defined prefixed commands. The "define" command can
2017 add new commands to existing prefixes, e.g. "target".
2019 * Multi-inferior, multi-process debugging.
2021 GDB now has generalized support for multi-inferior debugging. See
2022 "Debugging Multiple Inferiors" in the manual for more information.
2023 Although availability still depends on target support, the command
2024 set is more uniform now. The GNU/Linux specific multi-forks support
2025 has been migrated to this new framework. This implied some user
2026 visible changes; see "New commands" and also "Removed commands"
2029 * Target descriptions can now describe the target OS ABI. See the
2030 "Target Description Format" section in the user manual for more
2033 * Target descriptions can now describe "compatible" architectures
2034 to indicate that the target can execute applications for a different
2035 architecture in addition to those for the main target architecture.
2036 See the "Target Description Format" section in the user manual for
2039 * Multi-architecture debugging.
2041 GDB now includes general supports for debugging applications on
2042 hybrid systems that use more than one single processor architecture
2043 at the same time. Each such hybrid architecture still requires
2044 specific support to be added. The only hybrid architecture supported
2045 in this version of GDB is the Cell Broadband Engine.
2047 * GDB now supports integrated debugging of Cell/B.E. applications that
2048 use both the PPU and SPU architectures. To enable support for hybrid
2049 Cell/B.E. debugging, you need to configure GDB to support both the
2050 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2051 --enable-targets configure option.
2053 * Non-stop mode debugging.
2055 For some targets, GDB now supports an optional mode of operation in
2056 which you can examine stopped threads while other threads continue
2057 to execute freely. This is referred to as non-stop mode, with the
2058 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2059 section in the user manual for more information.
2061 To be able to support remote non-stop debugging, a remote stub needs
2062 to implement the non-stop mode remote protocol extensions, as
2063 described in the "Remote Non-Stop" section of the user manual. The
2064 GDB remote stub, gdbserver, has been adjusted to support these
2065 extensions on linux targets.
2067 * New commands (for set/show, see "New options" below)
2069 catch syscall [NAME(S) | NUMBER(S)]
2070 Catch system calls. Arguments, which should be names of system
2071 calls or their numbers, mean catch only those syscalls. Without
2072 arguments, every syscall will be caught. When the inferior issues
2073 any of the specified syscalls, GDB will stop and announce the system
2074 call, both when it is called and when its call returns. This
2075 feature is currently available with a native GDB running on the
2076 Linux Kernel, under the following architectures: x86, x86_64,
2077 PowerPC and PowerPC64.
2079 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2081 Search memory for a sequence of bytes.
2083 maint set python print-stack
2084 maint show python print-stack
2085 Show a stack trace when an error is encountered in a Python script.
2088 Invoke CODE by passing it to the Python interpreter.
2093 These allow macros to be defined, undefined, and listed
2097 Show operating system information about processes.
2100 List the inferiors currently under GDB's control.
2103 Switch focus to inferior number NUM.
2106 Detach from inferior number NUM.
2109 Kill inferior number NUM.
2113 set spu stop-on-load
2114 show spu stop-on-load
2115 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2117 set spu auto-flush-cache
2118 show spu auto-flush-cache
2119 Control whether to automatically flush the software-managed cache
2120 during Cell/B.E. debugging.
2122 set sh calling-convention
2123 show sh calling-convention
2124 Control the calling convention used when calling SH target functions.
2127 show debug timestamp
2128 Control display of timestamps with GDB debugging output.
2130 set disassemble-next-line
2131 show disassemble-next-line
2132 Control display of disassembled source lines or instructions when
2135 set remote noack-packet
2136 show remote noack-packet
2137 Set/show the use of remote protocol QStartNoAckMode packet. See above
2138 under "New remote packets."
2140 set remote query-attached-packet
2141 show remote query-attached-packet
2142 Control use of remote protocol `qAttached' (query-attached) packet.
2144 set remote read-siginfo-object
2145 show remote read-siginfo-object
2146 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2149 set remote write-siginfo-object
2150 show remote write-siginfo-object
2151 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2154 set remote reverse-continue
2155 show remote reverse-continue
2156 Control use of remote protocol 'bc' (reverse-continue) packet.
2158 set remote reverse-step
2159 show remote reverse-step
2160 Control use of remote protocol 'bs' (reverse-step) packet.
2162 set displaced-stepping
2163 show displaced-stepping
2164 Control displaced stepping mode. Displaced stepping is a way to
2165 single-step over breakpoints without removing them from the debuggee.
2166 Also known as "out-of-line single-stepping".
2169 show debug displaced
2170 Control display of debugging info for displaced stepping.
2172 maint set internal-error
2173 maint show internal-error
2174 Control what GDB does when an internal error is detected.
2176 maint set internal-warning
2177 maint show internal-warning
2178 Control what GDB does when an internal warning is detected.
2183 Use a wrapper program to launch programs for debugging.
2185 set multiple-symbols (all|ask|cancel)
2186 show multiple-symbols
2187 The value of this variable can be changed to adjust the debugger behavior
2188 when an expression or a breakpoint location contains an ambiguous symbol
2189 name (an overloaded function name, for instance).
2191 set breakpoint always-inserted
2192 show breakpoint always-inserted
2193 Keep breakpoints always inserted in the target, as opposed to inserting
2194 them when resuming the target, and removing them when the target stops.
2195 This option can improve debugger performance on slow remote targets.
2197 set arm fallback-mode (arm|thumb|auto)
2198 show arm fallback-mode
2199 set arm force-mode (arm|thumb|auto)
2201 These commands control how ARM GDB determines whether instructions
2202 are ARM or Thumb. The default for both settings is auto, which uses
2203 the current CPSR value for instructions without symbols; previous
2204 versions of GDB behaved as if "set arm fallback-mode arm".
2206 set disable-randomization
2207 show disable-randomization
2208 Standalone programs run with the virtual address space randomization enabled
2209 by default on some platforms. This option keeps the addresses stable across
2210 multiple debugging sessions.
2214 Control whether other threads are stopped or not when some thread hits
2219 Requests that asynchronous execution is enabled in the target, if available.
2220 In this case, it's possible to resume target in the background, and interact
2221 with GDB while the target is running. "show target-async" displays the
2222 current state of asynchronous execution of the target.
2224 set target-wide-charset
2225 show target-wide-charset
2226 The target-wide-charset is the name of the character set that GDB
2227 uses when printing characters whose type is wchar_t.
2229 set tcp auto-retry (on|off)
2231 set tcp connect-timeout
2232 show tcp connect-timeout
2233 These commands allow GDB to retry failed TCP connections to a remote stub
2234 with a specified timeout period; this is useful if the stub is launched
2235 in parallel with GDB but may not be ready to accept connections immediately.
2237 set libthread-db-search-path
2238 show libthread-db-search-path
2239 Control list of directories which GDB will search for appropriate
2242 set schedule-multiple (on|off)
2243 show schedule-multiple
2244 Allow GDB to resume all threads of all processes or only threads of
2245 the current process.
2249 Use more aggressive caching for accesses to the stack. This improves
2250 performance of remote debugging (particularly backtraces) without
2251 affecting correctness.
2253 set interactive-mode (on|off|auto)
2254 show interactive-mode
2255 Control whether GDB runs in interactive mode (on) or not (off).
2256 When in interactive mode, GDB waits for the user to answer all
2257 queries. Otherwise, GDB does not wait and assumes the default
2258 answer. When set to auto (the default), GDB determines which
2259 mode to use based on the stdin settings.
2264 For program forks, this is replaced by the new more generic `info
2265 inferiors' command. To list checkpoints, you can still use the
2266 `info checkpoints' command, which was an alias for the `info forks'
2270 Replaced by the new `inferior' command. To switch between
2271 checkpoints, you can still use the `restart' command, which was an
2272 alias for the `fork' command.
2275 This is removed, since some targets don't have a notion of
2276 processes. To switch between processes, you can still use the
2277 `inferior' command using GDB's own inferior number.
2280 For program forks, this is replaced by the new more generic `kill
2281 inferior' command. To delete a checkpoint, you can still use the
2282 `delete checkpoint' command, which was an alias for the `delete
2286 For program forks, this is replaced by the new more generic `detach
2287 inferior' command. To detach a checkpoint, you can still use the
2288 `detach checkpoint' command, which was an alias for the `detach
2291 * New native configurations
2293 x86/x86_64 Darwin i[34567]86-*-darwin*
2295 x86_64 MinGW x86_64-*-mingw*
2299 Lattice Mico32 lm32-*
2300 x86 DICOS i[34567]86-*-dicos*
2301 x86_64 DICOS x86_64-*-dicos*
2304 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2305 (mingw32ce) debugging.
2311 These commands were actually not implemented on any target.
2313 *** Changes in GDB 6.8
2315 * New native configurations
2317 NetBSD/hppa hppa*-*netbsd*
2318 Xtensa GNU/Linux xtensa*-*-linux*
2322 NetBSD/hppa hppa*-*-netbsd*
2323 Xtensa GNU/Lunux xtensa*-*-linux*
2325 * Change in command line behavior -- corefiles vs. process ids.
2327 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2328 attaching to process NUMBER fails, GDB no longer attempts to open a
2329 core file named NUMBER. Attaching to a program using the -c option
2330 is no longer supported. Instead, use the '-p' or '--pid' options.
2332 * GDB can now be built as a native debugger for debugging Windows x86
2333 (mingw32) Portable Executable (PE) programs.
2335 * Pending breakpoints no longer change their number when their address
2338 * GDB now supports breakpoints with multiple locations,
2339 including breakpoints on C++ constructors, inside C++ templates,
2340 and in inlined functions.
2342 * GDB's ability to debug optimized code has been improved. GDB more
2343 accurately identifies function bodies and lexical blocks that occupy
2344 more than one contiguous range of addresses.
2346 * Target descriptions can now describe registers for PowerPC.
2348 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2349 registers on PowerPC targets.
2351 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2352 targets even when the libthread_db library is not available.
2354 * The GDB remote stub, gdbserver, now supports the new file transfer
2355 commands (remote put, remote get, and remote delete).
2357 * The GDB remote stub, gdbserver, now supports run and attach in
2358 extended-remote mode.
2360 * hppa*64*-*-hpux11* target broken
2361 The debugger is unable to start a program and fails with the following
2362 error: "Error trying to get information about dynamic linker".
2363 The gdb-6.7 release is also affected.
2365 * GDB now supports the --enable-targets= configure option to allow
2366 building a single GDB executable that supports multiple remote
2367 target architectures.
2369 * GDB now supports debugging C and C++ programs which use the
2370 Decimal Floating Point extension. In addition, the PowerPC target
2371 now has a set of pseudo-registers to inspect decimal float values
2372 stored in two consecutive float registers.
2374 * The -break-insert MI command can optionally create pending
2377 * Improved support for debugging Ada
2378 Many improvements to the Ada language support have been made. These
2380 - Better support for Ada2005 interface types
2381 - Improved handling of arrays and slices in general
2382 - Better support for Taft-amendment types
2383 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2385 - Improved command completion in Ada
2388 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2393 set print frame-arguments (all|scalars|none)
2394 show print frame-arguments
2395 The value of this variable can be changed to control which argument
2396 values should be printed by the debugger when displaying a frame.
2401 Transfer files to and from a remote target, and delete remote files.
2408 Transfer files to and from a remote target, and delete remote files.
2410 * New remote packets
2417 Open, close, read, write, and delete files on the remote system.
2420 Attach to an existing process on the remote system, in extended-remote
2424 Run a new process on the remote system, in extended-remote mode.
2426 *** Changes in GDB 6.7
2428 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2429 bfd, libiberty and opcodes, as revealed by static analysis donated by
2430 Coverity, Inc. (http://scan.coverity.com).
2432 * When looking up multiply-defined global symbols, GDB will now prefer the
2433 symbol definition in the current shared library if it was built using the
2434 -Bsymbolic linker option.
2436 * When the Text User Interface (TUI) is not configured, GDB will now
2437 recognize the -tui command-line option and print a message that the TUI
2440 * The GDB remote stub, gdbserver, now has lower overhead for high
2441 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2443 * GDB for MIPS targets now autodetects whether a remote target provides
2444 32-bit or 64-bit register values.
2446 * Support for C++ member pointers has been improved.
2448 * GDB now understands XML target descriptions, which specify the
2449 target's overall architecture. GDB can read a description from
2450 a local file or over the remote serial protocol.
2452 * Vectors of single-byte data use a new integer type which is not
2453 automatically displayed as character or string data.
2455 * The /s format now works with the print command. It displays
2456 arrays of single-byte integers and pointers to single-byte integers
2459 * Target descriptions can now describe target-specific registers,
2460 for architectures which have implemented the support (currently
2461 only ARM, M68K, and MIPS).
2463 * GDB and the GDB remote stub, gdbserver, now support the XScale
2466 * The GDB remote stub, gdbserver, has been updated to support
2467 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2468 has been rewritten to use the standard GDB remote protocol.
2470 * GDB can now step into C++ functions which are called through thunks.
2472 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2474 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2475 layout. It also supports a TextSeg= and DataSeg= response when only
2476 segment base addresses (rather than offsets) are available.
2478 * The /i format now outputs any trailing branch delay slot instructions
2479 immediately following the last instruction within the count specified.
2481 * The GDB remote protocol "T" stop reply packet now supports a
2482 "library" response. Combined with the new "qXfer:libraries:read"
2483 packet, this response allows GDB to debug shared libraries on targets
2484 where the operating system manages the list of loaded libraries (e.g.
2485 Windows and SymbianOS).
2487 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2488 (DLLs) on Windows and Windows CE targets.
2490 * GDB now supports a faster verification that a .debug file matches its binary
2491 according to its build-id signature, if the signature is present.
2497 Enable or disable hardware flow control (RTS/CTS) on the serial port
2498 when debugging using remote targets.
2500 set mem inaccessible-by-default
2501 show mem inaccessible-by-default
2502 If the target supplies a memory map, for instance via the remote
2503 protocol's "qXfer:memory-map:read" packet, setting this variable
2504 prevents GDB from accessing memory outside the memory map. This
2505 is useful for targets with memory mapped registers or which react
2506 badly to accesses of unmapped address space.
2508 set breakpoint auto-hw
2509 show breakpoint auto-hw
2510 If the target supplies a memory map, for instance via the remote
2511 protocol's "qXfer:memory-map:read" packet, setting this variable
2512 lets GDB use hardware breakpoints automatically for memory regions
2513 where it can not use software breakpoints. This covers both the
2514 "break" command and internal breakpoints used for other commands
2515 including "next" and "finish".
2518 catch exception unhandled
2519 Stop the program execution when Ada exceptions are raised.
2522 Stop the program execution when an Ada assertion failed.
2526 Set an alternate system root for target files. This is a more
2527 general version of "set solib-absolute-prefix", which is now
2528 an alias to "set sysroot".
2531 Provide extended SPU facility status information. This set of
2532 commands is available only when debugging the Cell/B.E. SPU
2535 * New native configurations
2537 OpenBSD/sh sh*-*openbsd*
2540 unset tdesc filename
2542 Use the specified local file as an XML target description, and do
2543 not query the target for its built-in description.
2547 OpenBSD/sh sh*-*-openbsd*
2548 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2549 Toshiba Media Processor mep-elf
2551 * New remote packets
2554 Ignore the specified signals; pass them directly to the debugged program
2555 without stopping other threads or reporting them to GDB.
2557 qXfer:features:read:
2558 Read an XML target description from the target, which describes its
2563 Read or write contents of an spufs file on the target system. These
2564 packets are available only on the Cell/B.E. SPU architecture.
2566 qXfer:libraries:read:
2567 Report the loaded shared libraries. Combined with new "T" packet
2568 response, this packet allows GDB to debug shared libraries on
2569 targets where the operating system manages the list of loaded
2570 libraries (e.g. Windows and SymbianOS).
2574 Support for these obsolete configurations has been removed.
2582 i[34567]86-*-lynxos*
2583 i[34567]86-*-netware*
2584 i[34567]86-*-sco3.2v5*
2585 i[34567]86-*-sco3.2v4*
2587 i[34567]86-*-sysv4.2*
2590 i[34567]86-*-unixware2*
2591 i[34567]86-*-unixware*
2600 * Other removed features
2607 Various m68k-only ROM monitors.
2614 Various Renesas ROM monitors and debugging interfaces for SH and
2619 Support for a Macraigor serial interface to on-chip debugging.
2620 GDB does not directly support the newer parallel or USB
2625 A debug information format. The predecessor to DWARF 2 and
2626 DWARF 3, which are still supported.
2628 Support for the HP aCC compiler on HP-UX/PA-RISC
2630 SOM-encapsulated symbolic debugging information, automatic
2631 invocation of pxdb, and the aCC custom C++ ABI. This does not
2632 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2633 with aCC can still be debugged on an assembly level.
2635 MIPS ".pdr" sections
2637 A MIPS-specific format used to describe stack frame layout
2638 in debugging information.
2642 GDB could work with an older version of Guile to debug
2643 the interpreter and Scheme programs running in it.
2645 set mips stack-arg-size
2646 set mips saved-gpreg-size
2648 Use "set mips abi" to control parameter passing for MIPS.
2650 *** Changes in GDB 6.6
2655 Cell Broadband Engine SPU spu-elf
2657 * GDB can now be configured as a cross-debugger targeting native Windows
2658 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2659 running on a Windows system over TCP/IP to debug Windows programs.
2661 * The GDB remote stub, gdbserver, has been updated to support Windows and
2662 Cygwin debugging. Both single-threaded and multi-threaded programs are
2665 * The "set trust-readonly-sections" command works again. This command was
2666 broken in GDB 6.3, 6.4, and 6.5.
2668 * The "load" command now supports writing to flash memory, if the remote
2669 stub provides the required support.
2671 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2672 longer requires symbolic debug information (e.g. DWARF-2).
2677 unset substitute-path
2678 show substitute-path
2679 Manage a list of substitution rules that GDB uses to rewrite the name
2680 of the directories where the sources are located. This can be useful
2681 for instance when the sources were moved to a different location
2682 between compilation and debugging.
2686 Print each CLI command as it is executed. Each command is prefixed with
2687 a number of `+' symbols representing the nesting depth.
2688 The source command now has a `-v' option to enable the same feature.
2692 The ARM Demon monitor support (RDP protocol, "target rdp").
2694 Kernel Object Display, an embedded debugging feature which only worked with
2695 an obsolete version of Cisco IOS.
2697 The 'set download-write-size' and 'show download-write-size' commands.
2699 * New remote packets
2702 Tell a stub about GDB client features, and request remote target features.
2703 The first feature implemented is PacketSize, which allows the target to
2704 specify the size of packets it can handle - to minimize the number of
2705 packets required and improve performance when connected to a remote
2709 Fetch an OS auxilliary vector from the remote stub. This packet is a
2710 more efficient replacement for qPart:auxv:read.
2712 qXfer:memory-map:read:
2713 Fetch a memory map from the remote stub, including information about
2714 RAM, ROM, and flash memory devices.
2719 Erase and program a flash memory device.
2721 * Removed remote packets
2724 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2725 used it, and only gdbserver implemented it.
2727 *** Changes in GDB 6.5
2731 Renesas M32C/M16C m32c-elf
2733 Morpho Technologies ms1 ms1-elf
2737 init-if-undefined Initialize a convenience variable, but
2738 only if it doesn't already have a value.
2740 The following commands are presently only implemented for native GNU/Linux:
2742 checkpoint Save a snapshot of the program state.
2744 restart <n> Return the program state to a
2745 previously saved state.
2747 info checkpoints List currently saved checkpoints.
2749 delete-checkpoint <n> Delete a previously saved checkpoint.
2751 set|show detach-on-fork Tell gdb whether to detach from a newly
2752 forked process, or to keep debugging it.
2754 info forks List forks of the user program that
2755 are available to be debugged.
2757 fork <n> Switch to debugging one of several
2758 forks of the user program that are
2759 available to be debugged.
2761 delete-fork <n> Delete a fork from the list of forks
2762 that are available to be debugged (and
2763 kill the forked process).
2765 detach-fork <n> Delete a fork from the list of forks
2766 that are available to be debugged (and
2767 allow the process to continue).
2771 Morpho Technologies ms2 ms1-elf
2773 * Improved Windows host support
2775 GDB now builds as a cross debugger hosted on i686-mingw32, including
2776 native console support, and remote communications using either
2777 network sockets or serial ports.
2779 * Improved Modula-2 language support
2781 GDB can now print most types in the Modula-2 syntax. This includes:
2782 basic types, set types, record types, enumerated types, range types,
2783 pointer types and ARRAY types. Procedure var parameters are correctly
2784 printed and hexadecimal addresses and character constants are also
2785 written in the Modula-2 syntax. Best results can be obtained by using
2786 GNU Modula-2 together with the -gdwarf-2 command line option.
2790 The ARM rdi-share module.
2792 The Netware NLM debug server.
2794 *** Changes in GDB 6.4
2796 * New native configurations
2798 OpenBSD/arm arm*-*-openbsd*
2799 OpenBSD/mips64 mips64-*-openbsd*
2803 Morpho Technologies ms1 ms1-elf
2805 * New command line options
2807 --batch-silent As for --batch, but totally silent.
2808 --return-child-result The debugger will exist with the same value
2809 the child (debugged) program exited with.
2810 --eval-command COMMAND, -ex COMMAND
2811 Execute a single GDB CLI command. This may be
2812 specified multiple times and in conjunction
2813 with the --command (-x) option.
2815 * Deprecated commands removed
2817 The following commands, that were deprecated in 2000, have been
2821 set|show arm disassembly-flavor set|show arm disassembler
2822 othernames set arm disassembler
2823 set|show remotedebug set|show debug remote
2824 set|show archdebug set|show debug arch
2825 set|show eventdebug set|show debug event
2828 * New BSD user-level threads support
2830 It is now possible to debug programs using the user-level threads
2831 library on OpenBSD and FreeBSD. Currently supported (target)
2834 FreeBSD/amd64 x86_64-*-freebsd*
2835 FreeBSD/i386 i386-*-freebsd*
2836 OpenBSD/i386 i386-*-openbsd*
2838 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2839 are not yet supported.
2841 * New support for Matsushita MN10300 w/sim added
2842 (Work in progress). mn10300-elf.
2844 * REMOVED configurations and files
2846 VxWorks and the XDR protocol *-*-vxworks
2847 Motorola MCORE mcore-*-*
2848 National Semiconductor NS32000 ns32k-*-*
2850 * New "set print array-indexes" command
2852 After turning this setting "on", GDB prints the index of each element
2853 when displaying arrays. The default is "off" to preserve the previous
2856 * VAX floating point support
2858 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2860 * User-defined command support
2862 In addition to using $arg0..$arg9 for argument passing, it is now possible
2863 to use $argc to determine now many arguments have been passed. See the
2864 section on user-defined commands in the user manual for more information.
2866 *** Changes in GDB 6.3:
2868 * New command line option
2870 GDB now accepts -l followed by a number to set the timeout for remote
2873 * GDB works with GCC -feliminate-dwarf2-dups
2875 GDB now supports a more compact representation of DWARF-2 debug
2876 information using DW_FORM_ref_addr references. These are produced
2877 by GCC with the option -feliminate-dwarf2-dups and also by some
2878 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2879 to use -feliminate-dwarf2-dups.
2881 * Internationalization
2883 When supported by the host system, GDB will be built with
2884 internationalization (libintl). The task of marking up the sources is
2885 continued, we're looking forward to our first translation.
2889 Initial support for debugging programs compiled with the GNAT
2890 implementation of the Ada programming language has been integrated
2891 into GDB. In this release, support is limited to expression evaluation.
2893 * New native configurations
2895 GNU/Linux/m32r m32r-*-linux-gnu
2899 GDB's remote protocol now includes support for the 'p' packet. This
2900 packet is used to fetch individual registers from a remote inferior.
2902 * END-OF-LIFE registers[] compatibility module
2904 GDB's internal register infrastructure has been completely rewritten.
2905 The new infrastructure making possible the implementation of key new
2906 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2909 GDB 6.3 will be the last release to include the the registers[]
2910 compatibility module that allowed out-of-date configurations to
2911 continue to work. This change directly impacts the following
2921 powerpc bdm protocol
2923 Unless there is activity to revive these configurations, they will be
2924 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2926 * OBSOLETE configurations and files
2928 Configurations that have been declared obsolete in this release have
2929 been commented out. Unless there is activity to revive these
2930 configurations, the next release of GDB will have their sources
2931 permanently REMOVED.
2940 *** Changes in GDB 6.2.1:
2942 * MIPS `break main; run' gave an heuristic-fence-post warning
2944 When attempting to run even a simple program, a warning about
2945 heuristic-fence-post being hit would be reported. This problem has
2948 * MIPS IRIX 'long double' crashed GDB
2950 When examining a long double variable, GDB would get a segmentation
2951 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2952 IRIX long double values).
2956 A bug in the VAX stack code was causing problems with the "next"
2957 command. This problem has been fixed.
2959 *** Changes in GDB 6.2:
2961 * Fix for ``many threads''
2963 On GNU/Linux systems that use the NPTL threads library, a program
2964 rapidly creating and deleting threads would confuse GDB leading to the
2967 ptrace: No such process.
2968 thread_db_get_info: cannot get thread info: generic error
2970 This problem has been fixed.
2972 * "-async" and "-noasync" options removed.
2974 Support for the broken "-noasync" option has been removed (it caused
2977 * New ``start'' command.
2979 This command runs the program until the begining of the main procedure.
2981 * New BSD Kernel Data Access Library (libkvm) interface
2983 Using ``target kvm'' it is now possible to debug kernel core dumps and
2984 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2985 platforms. Currently supported (native-only) configurations are:
2987 FreeBSD/amd64 x86_64-*-freebsd*
2988 FreeBSD/i386 i?86-*-freebsd*
2989 NetBSD/i386 i?86-*-netbsd*
2990 NetBSD/m68k m68*-*-netbsd*
2991 NetBSD/sparc sparc-*-netbsd*
2992 OpenBSD/amd64 x86_64-*-openbsd*
2993 OpenBSD/i386 i?86-*-openbsd*
2994 OpenBSD/m68k m68*-openbsd*
2995 OpenBSD/sparc sparc-*-openbsd*
2997 * Signal trampoline code overhauled
2999 Many generic problems with GDB's signal handling code have been fixed.
3000 These include: backtraces through non-contiguous stacks; recognition
3001 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3002 call; backtrace through a signal trampoline; step into and out of
3003 signal handlers; and single-stepping in the signal trampoline.
3005 Please note that kernel bugs are a limiting factor here. These
3006 features have been shown to work on an s390 GNU/Linux system that
3007 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3009 * Cygwin support for DWARF 2 added.
3011 * New native configurations
3013 GNU/Linux/hppa hppa*-*-linux*
3014 OpenBSD/hppa hppa*-*-openbsd*
3015 OpenBSD/m68k m68*-*-openbsd*
3016 OpenBSD/m88k m88*-*-openbsd*
3017 OpenBSD/powerpc powerpc-*-openbsd*
3018 NetBSD/vax vax-*-netbsd*
3019 OpenBSD/vax vax-*-openbsd*
3021 * END-OF-LIFE frame compatibility module
3023 GDB's internal frame infrastructure has been completely rewritten.
3024 The new infrastructure making it possible to support key new features
3025 including DWARF 2 Call Frame Information. To aid in the task of
3026 migrating old configurations to this new infrastructure, a
3027 compatibility module, that allowed old configurations to continue to
3028 work, was also included.
3030 GDB 6.2 will be the last release to include this frame compatibility
3031 module. This change directly impacts the following configurations:
3041 Unless there is activity to revive these configurations, they will be
3042 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3044 * REMOVED configurations and files
3046 Sun 3, running SunOS 3 m68*-*-sunos3*
3047 Sun 3, running SunOS 4 m68*-*-sunos4*
3048 Sun 2, running SunOS 3 m68000-*-sunos3*
3049 Sun 2, running SunOS 4 m68000-*-sunos4*
3050 Motorola 680x0 running LynxOS m68*-*-lynxos*
3051 AT&T 3b1/Unix pc m68*-att-*
3052 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3053 decstation mips-dec-* mips-little-*
3054 riscos mips-*-riscos* mips-*-sysv*
3055 sonymips mips-sony-*
3056 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3058 *** Changes in GDB 6.1.1:
3060 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3062 The TUI (Text-mode User Interface) is now built as part of a default
3063 GDB configuration. It is enabled by either selecting the TUI with the
3064 command line option "-i=tui" or by running the separate "gdbtui"
3065 program. For more information on the TUI, see the manual "Debugging
3068 * Pending breakpoint support (also included in GDB 6.1)
3070 Support has been added to allow you to specify breakpoints in shared
3071 libraries that have not yet been loaded. If a breakpoint location
3072 cannot be found, and the "breakpoint pending" option is set to auto,
3073 GDB queries you if you wish to make the breakpoint pending on a future
3074 shared-library load. If and when GDB resolves the breakpoint symbol,
3075 the pending breakpoint is removed as one or more regular breakpoints
3078 Pending breakpoints are very useful for GCJ Java debugging.
3080 * Fixed ISO-C build problems
3082 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3083 non ISO-C code that stopped them being built using a more strict ISO-C
3084 compiler (e.g., IBM's C compiler).
3086 * Fixed build problem on IRIX 5
3088 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3089 wasn't able to compile compile on an IRIX 5 system.
3091 * Added execute permission to gdb/gdbserver/configure
3093 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3094 permission. This bug would cause configure to fail on a number of
3095 systems (Solaris, IRIX). Ref: server/519.
3097 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3099 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3100 has been updated to use constant array sizes.
3102 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3104 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3105 its generated DWARF Call Frame Info. This encoding was causing GDB to
3106 panic, that panic has been fixed. Ref: gdb/1628.
3108 * Fixed a problem when examining parameters in shared library code.
3110 When examining parameters in optimized shared library code generated
3111 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3112 not available''. GDB now correctly displays the variable's value.
3114 *** Changes in GDB 6.1:
3116 * Removed --with-mmalloc
3118 Support for the mmalloc memory manager has been removed, as it
3119 conflicted with the internal gdb byte cache.
3121 * Changes in AMD64 configurations
3123 The AMD64 target now includes the %cs and %ss registers. As a result
3124 the AMD64 remote protocol has changed; this affects the floating-point
3125 and SSE registers. If you rely on those registers for your debugging,
3126 you should upgrade gdbserver on the remote side.
3128 * Revised SPARC target
3130 The SPARC target has been completely revised, incorporating the
3131 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3132 support for LynxOS and SunOS 4 has been dropped. Calling functions
3133 from within GDB on operating systems with a non-executable stack
3134 (Solaris, OpenBSD) now works.
3138 GDB has a new C++ demangler which does a better job on the mangled
3139 names generated by current versions of g++. It also runs faster, so
3140 with this and other changes gdb should now start faster on large C++
3143 * DWARF 2 Location Expressions
3145 GDB support for location expressions has been extended to support function
3146 arguments and frame bases. Older versions of GDB could crash when they
3149 * C++ nested types and namespaces
3151 GDB's support for nested types and namespaces in C++ has been
3152 improved, especially if you use the DWARF 2 debugging format. (This
3153 is the default for recent versions of GCC on most platforms.)
3154 Specifically, if you have a class "Inner" defined within a class or
3155 namespace "Outer", then GDB realizes that the class's name is
3156 "Outer::Inner", not simply "Inner". This should greatly reduce the
3157 frequency of complaints about not finding RTTI symbols. In addition,
3158 if you are stopped at inside of a function defined within a namespace,
3159 GDB modifies its name lookup accordingly.
3161 * New native configurations
3163 NetBSD/amd64 x86_64-*-netbsd*
3164 OpenBSD/amd64 x86_64-*-openbsd*
3165 OpenBSD/alpha alpha*-*-openbsd*
3166 OpenBSD/sparc sparc-*-openbsd*
3167 OpenBSD/sparc64 sparc64-*-openbsd*
3169 * New debugging protocols
3171 M32R with SDI protocol m32r-*-elf*
3173 * "set prompt-escape-char" command deleted.
3175 The command "set prompt-escape-char" has been deleted. This command,
3176 and its very obscure effet on GDB's prompt, was never documented,
3177 tested, nor mentioned in the NEWS file.
3179 * OBSOLETE configurations and files
3181 Configurations that have been declared obsolete in this release have
3182 been commented out. Unless there is activity to revive these
3183 configurations, the next release of GDB will have their sources
3184 permanently REMOVED.
3186 Sun 3, running SunOS 3 m68*-*-sunos3*
3187 Sun 3, running SunOS 4 m68*-*-sunos4*
3188 Sun 2, running SunOS 3 m68000-*-sunos3*
3189 Sun 2, running SunOS 4 m68000-*-sunos4*
3190 Motorola 680x0 running LynxOS m68*-*-lynxos*
3191 AT&T 3b1/Unix pc m68*-att-*
3192 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3193 decstation mips-dec-* mips-little-*
3194 riscos mips-*-riscos* mips-*-sysv*
3195 sonymips mips-sony-*
3196 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3198 * REMOVED configurations and files
3200 SGI Irix-4.x mips-sgi-irix4 or iris4
3201 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3202 Z8000 simulator z8k-zilog-none or z8ksim
3203 Matsushita MN10200 w/simulator mn10200-*-*
3204 H8/500 simulator h8500-hitachi-hms or h8500hms
3205 HP/PA running BSD hppa*-*-bsd*
3206 HP/PA running OSF/1 hppa*-*-osf*
3207 HP/PA Pro target hppa*-*-pro*
3208 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3209 386BSD i[3456]86-*-bsd*
3210 Sequent family i[3456]86-sequent-sysv4*
3211 i[3456]86-sequent-sysv*
3212 i[3456]86-sequent-bsd*
3213 SPARC running LynxOS sparc-*-lynxos*
3214 SPARC running SunOS 4 sparc-*-sunos4*
3215 Tsqware Sparclet sparclet-*-*
3216 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3218 *** Changes in GDB 6.0:
3222 Support for debugging the Objective-C programming language has been
3223 integrated into GDB.
3225 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3227 DWARF 2's Call Frame Information makes available compiler generated
3228 information that more exactly describes the program's run-time stack.
3229 By using this information, GDB is able to provide more robust stack
3232 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3233 have been updated to use a new backtrace mechanism which includes
3234 DWARF 2 CFI support.
3238 GDB's remote protocol has been extended to include support for hosted
3239 file I/O (where the remote target uses GDB's file system). See GDB's
3240 remote protocol documentation for details.
3242 * All targets using the new architecture framework.
3244 All of GDB's targets have been updated to use the new internal
3245 architecture framework. The way is now open for future GDB releases
3246 to include cross-architecture native debugging support (i386 on amd64,
3249 * GNU/Linux's Thread Local Storage (TLS)
3251 GDB now includes support for for the GNU/Linux implementation of
3252 per-thread variables.
3254 * GNU/Linux's Native POSIX Thread Library (NPTL)
3256 GDB's thread code has been updated to work with either the new
3257 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3259 * Separate debug info.
3261 GDB, in conjunction with BINUTILS, now supports a mechanism for
3262 automatically loading debug information from a separate file. Instead
3263 of shipping full debug and non-debug versions of system libraries,
3264 system integrators can now instead ship just the stripped libraries
3265 and optional debug files.
3267 * DWARF 2 Location Expressions
3269 DWARF 2 Location Expressions allow the compiler to more completely
3270 describe the location of variables (even in optimized code) to the
3273 GDB now includes preliminary support for location expressions (support
3274 for DW_OP_piece is still missing).
3278 A number of long standing bugs that caused GDB to die while starting a
3279 Java application have been fixed. GDB's Java support is now
3280 considered "useable".
3282 * GNU/Linux support for fork, vfork, and exec.
3284 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3285 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3288 * GDB supports logging output to a file
3290 There are two new commands, "set logging" and "show logging", which can be
3291 used to capture GDB's output to a file.
3293 * The meaning of "detach" has changed for gdbserver
3295 The "detach" command will now resume the application, as documented. To
3296 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3299 * d10v, m68hc11 `regs' command deprecated
3301 The `info registers' command has been updated so that it displays the
3302 registers using a format identical to the old `regs' command.
3306 A new command, "maint set profile on/off", has been added. This command can
3307 be used to enable or disable profiling while running GDB, to profile a
3308 session or a set of commands. In addition there is a new configure switch,
3309 "--enable-profiling", which will cause GDB to be compiled with profiling
3310 data, for more informative profiling results.
3312 * Default MI syntax changed to "mi2".
3314 The default MI (machine interface) syntax, enabled by the command line
3315 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3316 "mi1", can be enabled by specifying the option "-i=mi1".
3318 Support for the original "mi0" syntax (included in GDB 5.0) has been
3321 Fix for gdb/192: removed extraneous space when displaying frame level.
3322 Fix for gdb/672: update changelist is now output in mi list format.
3323 Fix for gdb/702: a -var-assign that updates the value now shows up
3324 in a subsequent -var-update.
3326 * New native configurations.
3328 FreeBSD/amd64 x86_64-*-freebsd*
3330 * Multi-arched targets.
3332 HP/PA HPUX11 hppa*-*-hpux*
3333 Renesas M32R/D w/simulator m32r-*-elf*
3335 * OBSOLETE configurations and files
3337 Configurations that have been declared obsolete in this release have
3338 been commented out. Unless there is activity to revive these
3339 configurations, the next release of GDB will have their sources
3340 permanently REMOVED.
3342 Z8000 simulator z8k-zilog-none or z8ksim
3343 Matsushita MN10200 w/simulator mn10200-*-*
3344 H8/500 simulator h8500-hitachi-hms or h8500hms
3345 HP/PA running BSD hppa*-*-bsd*
3346 HP/PA running OSF/1 hppa*-*-osf*
3347 HP/PA Pro target hppa*-*-pro*
3348 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3349 Sequent family i[3456]86-sequent-sysv4*
3350 i[3456]86-sequent-sysv*
3351 i[3456]86-sequent-bsd*
3352 Tsqware Sparclet sparclet-*-*
3353 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3355 * REMOVED configurations and files
3358 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3359 IBM AIX PS/2 i[3456]86-*-aix
3360 i386 running Mach 3.0 i[3456]86-*-mach3*
3361 i386 running Mach i[3456]86-*-mach*
3362 i386 running OSF/1 i[3456]86-*osf1mk*
3363 HP/Apollo 68k Family m68*-apollo*-sysv*,
3365 m68*-hp-bsd*, m68*-hp-hpux*
3366 Argonaut Risc Chip (ARC) arc-*-*
3367 Mitsubishi D30V d30v-*-*
3368 Fujitsu FR30 fr30-*-elf*
3369 OS/9000 i[34]86-*-os9k
3370 I960 with MON960 i960-*-coff
3372 * MIPS $fp behavior changed
3374 The convenience variable $fp, for the MIPS, now consistently returns
3375 the address of the current frame's base. Previously, depending on the
3376 context, $fp could refer to either $sp or the current frame's base
3377 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3378 The GNU Source-Level Debugger''.
3380 *** Changes in GDB 5.3:
3382 * GNU/Linux shared library multi-threaded performance improved.
3384 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3385 `/proc', in preference to `ptrace' for memory reads. This may result
3386 in an improvement in the start-up time of multi-threaded, shared
3387 library applications when run under GDB. One GDB user writes: ``loads
3388 shared libs like mad''.
3390 * ``gdbserver'' now supports multi-threaded applications on some targets
3392 Support for debugging multi-threaded applications which use
3393 the GNU/Linux LinuxThreads package has been added for
3394 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3395 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3397 * GDB now supports C/C++ preprocessor macros.
3399 GDB now expands preprocessor macro invocations in C/C++ expressions,
3400 and provides various commands for showing macro definitions and how
3403 The new command `macro expand EXPRESSION' expands any macro
3404 invocations in expression, and shows the result.
3406 The new command `show macro MACRO-NAME' shows the definition of the
3407 macro named MACRO-NAME, and where it was defined.
3409 Most compilers don't include information about macros in the debugging
3410 information by default. In GCC 3.1, for example, you need to compile
3411 your program with the options `-gdwarf-2 -g3'. If the macro
3412 information is present in the executable, GDB will read it.
3414 * Multi-arched targets.
3416 DEC Alpha (partial) alpha*-*-*
3417 DEC VAX (partial) vax-*-*
3419 National Semiconductor NS32000 (partial) ns32k-*-*
3420 Motorola 68000 (partial) m68k-*-*
3421 Motorola MCORE mcore-*-*
3425 Fujitsu FRV architecture added by Red Hat frv*-*-*
3428 * New native configurations
3430 Alpha NetBSD alpha*-*-netbsd*
3431 SH NetBSD sh*-*-netbsdelf*
3432 MIPS NetBSD mips*-*-netbsd*
3433 UltraSPARC NetBSD sparc64-*-netbsd*
3435 * OBSOLETE configurations and files
3437 Configurations that have been declared obsolete in this release have
3438 been commented out. Unless there is activity to revive these
3439 configurations, the next release of GDB will have their sources
3440 permanently REMOVED.
3442 Mitsubishi D30V d30v-*-*
3443 OS/9000 i[34]86-*-os9k
3444 IBM AIX PS/2 i[3456]86-*-aix
3445 Fujitsu FR30 fr30-*-elf*
3446 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3447 Argonaut Risc Chip (ARC) arc-*-*
3448 i386 running Mach 3.0 i[3456]86-*-mach3*
3449 i386 running Mach i[3456]86-*-mach*
3450 i386 running OSF/1 i[3456]86-*osf1mk*
3451 HP/Apollo 68k Family m68*-apollo*-sysv*,
3453 m68*-hp-bsd*, m68*-hp-hpux*
3454 I960 with MON960 i960-*-coff
3456 * OBSOLETE languages
3458 CHILL, a Pascal like language used by telecommunications companies.
3460 * REMOVED configurations and files
3462 AMD 29k family via UDI a29k-amd-udi, udi29k
3463 A29K VxWorks a29k-*-vxworks
3464 AMD 29000 embedded, using EBMON a29k-none-none
3465 AMD 29000 embedded with COFF a29k-none-coff
3466 AMD 29000 embedded with a.out a29k-none-aout
3468 testsuite/gdb.hp/gdb.threads-hp/ directory
3470 * New command "set max-user-call-depth <nnn>"
3472 This command allows the user to limit the call depth of user-defined
3473 commands. The default is 1024.
3475 * Changes in FreeBSD/i386 native debugging.
3477 Support for the "generate-core-file" has been added.
3479 * New commands "dump", "append", and "restore".
3481 These commands allow data to be copied from target memory
3482 to a bfd-format or binary file (dump and append), and back
3483 from a file into memory (restore).
3485 * Improved "next/step" support on multi-processor Alpha Tru64.
3487 The previous single-step mechanism could cause unpredictable problems,
3488 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3489 of a software single-step mechanism prevents this.
3491 *** Changes in GDB 5.2.1:
3499 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3500 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3501 Fix, by Joel Brobecker imported from mainline.
3503 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3504 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3505 Fix, by Fred Fish, imported from mainline.
3507 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3508 Surprisingly enough, it works now.
3509 By Michal Ludvig, imported from mainline.
3511 i386 hardware watchpoint support:
3512 avoid misses on second run for some targets.
3513 By Pierre Muller, imported from mainline.
3515 *** Changes in GDB 5.2:
3517 * New command "set trust-readonly-sections on[off]".
3519 This command is a hint that tells gdb that read-only sections
3520 really are read-only (ie. that their contents will not change).
3521 In this mode, gdb will go to the object file rather than the
3522 target to read memory from read-only sections (such as ".text").
3523 This can be a significant performance improvement on some
3524 (notably embedded) targets.
3526 * New command "generate-core-file" (or "gcore").
3528 This new gdb command allows the user to drop a core file of the child
3529 process state at any time. So far it's been implemented only for
3530 GNU/Linux and Solaris, but should be relatively easily ported to other
3531 hosts. Argument is core file name (defaults to core.<pid>).
3533 * New command line option
3535 GDB now accepts --pid or -p followed by a process id.
3537 * Change in command line behavior -- corefiles vs. process ids.
3539 There is a subtle behavior in the way in which GDB handles
3540 command line arguments. The first non-flag argument is always
3541 a program to debug, but the second non-flag argument may either
3542 be a corefile or a process id. Previously, GDB would attempt to
3543 open the second argument as a corefile, and if that failed, would
3544 issue a superfluous error message and then attempt to attach it as
3545 a process. Now, if the second argument begins with a non-digit,
3546 it will be treated as a corefile. If it begins with a digit,
3547 GDB will attempt to attach it as a process, and if no such process
3548 is found, will then attempt to open it as a corefile.
3550 * Changes in ARM configurations.
3552 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3553 configuration is fully multi-arch.
3555 * New native configurations
3557 ARM NetBSD arm*-*-netbsd*
3558 x86 OpenBSD i[3456]86-*-openbsd*
3559 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3560 Sparc64 running FreeBSD sparc64-*-freebsd*
3564 Sanyo XStormy16 xstormy16-elf
3566 * OBSOLETE configurations and files
3568 Configurations that have been declared obsolete in this release have
3569 been commented out. Unless there is activity to revive these
3570 configurations, the next release of GDB will have their sources
3571 permanently REMOVED.
3573 AMD 29k family via UDI a29k-amd-udi, udi29k
3574 A29K VxWorks a29k-*-vxworks
3575 AMD 29000 embedded, using EBMON a29k-none-none
3576 AMD 29000 embedded with COFF a29k-none-coff
3577 AMD 29000 embedded with a.out a29k-none-aout
3579 testsuite/gdb.hp/gdb.threads-hp/ directory
3581 * REMOVED configurations and files
3583 TI TMS320C80 tic80-*-*
3585 PowerPC Solaris powerpcle-*-solaris*
3586 PowerPC Windows NT powerpcle-*-cygwin32
3587 PowerPC Netware powerpc-*-netware*
3588 Harris/CXUX m88k m88*-harris-cxux*
3589 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3590 ns32k-utek-sysv* ns32k-utek-*
3591 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3592 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3593 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3594 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3595 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3597 * Changes to command line processing
3599 The new `--args' feature can be used to specify command-line arguments
3600 for the inferior from gdb's command line.
3602 * Changes to key bindings
3604 There is a new `operate-and-get-next' function bound to `C-o'.
3606 *** Changes in GDB 5.1.1
3608 Fix compile problem on DJGPP.
3610 Fix a problem with floating-point registers on the i386 being
3613 Fix to stop GDB crashing on .debug_str debug info.
3615 Numerous documentation fixes.
3617 Numerous testsuite fixes.
3619 *** Changes in GDB 5.1:
3621 * New native configurations
3623 Alpha FreeBSD alpha*-*-freebsd*
3624 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3625 MIPS GNU/Linux mips*-*-linux*
3626 MIPS SGI Irix 6.x mips*-sgi-irix6*
3627 ia64 AIX ia64-*-aix*
3628 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3632 Motorola 68HC11 and 68HC12 m68hc11-elf
3634 UltraSparc running GNU/Linux sparc64-*-linux*
3636 * OBSOLETE configurations and files
3638 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3639 Harris/CXUX m88k m88*-harris-cxux*
3640 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3641 ns32k-utek-sysv* ns32k-utek-*
3642 TI TMS320C80 tic80-*-*
3644 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3645 PowerPC Solaris powerpcle-*-solaris*
3646 PowerPC Windows NT powerpcle-*-cygwin32
3647 PowerPC Netware powerpc-*-netware*
3648 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3649 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3650 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3651 Apple Macintosh (MPW) host N/A
3653 stuff.c (Program to stuff files into a specially prepared space in kdb)
3654 kdb-start.c (Main loop for the standalone kernel debugger)
3656 Configurations that have been declared obsolete in this release have
3657 been commented out. Unless there is activity to revive these
3658 configurations, the next release of GDB will have their sources
3659 permanently REMOVED.
3661 * REMOVED configurations and files
3663 Altos 3068 m68*-altos-*
3664 Convex c1-*-*, c2-*-*
3666 ARM RISCix arm-*-* (as host)
3670 * GDB has been converted to ISO C.
3672 GDB's source code has been converted to ISO C. In particular, the
3673 sources are fully protoized, and rely on standard headers being
3678 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3680 * The MI enabled by default.
3682 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3683 revised and enabled by default. Packages which use GDB as a debugging
3684 engine behind a UI or another front end are encouraged to switch to
3685 using the GDB/MI interface, instead of the old annotations interface
3686 which is now deprecated.
3688 * Support for debugging Pascal programs.
3690 GDB now includes support for debugging Pascal programs. The following
3691 main features are supported:
3693 - Pascal-specific data types such as sets;
3695 - automatic recognition of Pascal sources based on file-name
3698 - Pascal-style display of data types, variables, and functions;
3700 - a Pascal expression parser.
3702 However, some important features are not yet supported.
3704 - Pascal string operations are not supported at all;
3706 - there are some problems with boolean types;
3708 - Pascal type hexadecimal constants are not supported
3709 because they conflict with the internal variables format;
3711 - support for Pascal objects and classes is not full yet;
3713 - unlike Pascal, GDB is case-sensitive for symbol names.
3715 * Changes in completion.
3717 Commands such as `shell', `run' and `set args', which pass arguments
3718 to inferior programs, now complete on file names, similar to what
3719 users expect at the shell prompt.
3721 Commands which accept locations, such as `disassemble', `print',
3722 `breakpoint', `until', etc. now complete on filenames as well as
3723 program symbols. Thus, if you type "break foob TAB", and the source
3724 files linked into the programs include `foobar.c', that file name will
3725 be one of the candidates for completion. However, file names are not
3726 considered for completion after you typed a colon that delimits a file
3727 name from a name of a function in that file, as in "break foo.c:bar".
3729 `set demangle-style' completes on available demangling styles.
3731 * New platform-independent commands:
3733 It is now possible to define a post-hook for a command as well as a
3734 hook that runs before the command. For more details, see the
3735 documentation of `hookpost' in the GDB manual.
3737 * Changes in GNU/Linux native debugging.
3739 Support for debugging multi-threaded programs has been completely
3740 revised for all platforms except m68k and sparc. You can now debug as
3741 many threads as your system allows you to have.
3743 Attach/detach is supported for multi-threaded programs.
3745 Support for SSE registers was added for x86. This doesn't work for
3746 multi-threaded programs though.
3748 * Changes in MIPS configurations.
3750 Multi-arch support is enabled for all MIPS configurations.
3752 GDB can now be built as native debugger on SGI Irix 6.x systems for
3753 debugging n32 executables. (Debugging 64-bit executables is not yet
3756 * Unified support for hardware watchpoints in all x86 configurations.
3758 Most (if not all) native x86 configurations support hardware-assisted
3759 breakpoints and watchpoints in a unified manner. This support
3760 implements debug register sharing between watchpoints, which allows to
3761 put a virtually infinite number of watchpoints on the same address,
3762 and also supports watching regions up to 16 bytes with several debug
3765 The new maintenance command `maintenance show-debug-regs' toggles
3766 debugging print-outs in functions that insert, remove, and test
3767 watchpoints and hardware breakpoints.
3769 * Changes in the DJGPP native configuration.
3771 New command ``info dos sysinfo'' displays assorted information about
3772 the CPU, OS, memory, and DPMI server.
3774 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3775 display information about segment descriptors stored in GDT, LDT, and
3778 New commands ``info dos pde'' and ``info dos pte'' display entries
3779 from Page Directory and Page Tables (for now works with CWSDPMI only).
3780 New command ``info dos address-pte'' displays the Page Table entry for
3781 a given linear address.
3783 GDB can now pass command lines longer than 126 characters to the
3784 program being debugged (requires an update to the libdbg.a library
3785 which is part of the DJGPP development kit).
3787 DWARF2 debug info is now supported.
3789 It is now possible to `step' and `next' through calls to `longjmp'.
3791 * Changes in documentation.
3793 All GDB documentation was converted to GFDL, the GNU Free
3794 Documentation License.
3796 Tracepoints-related commands are now fully documented in the GDB
3799 TUI, the Text-mode User Interface, is now documented in the manual.
3801 Tracepoints-related commands are now fully documented in the GDB
3804 The "GDB Internals" manual now has an index. It also includes
3805 documentation of `ui_out' functions, GDB coding standards, x86
3806 hardware watchpoints, and memory region attributes.
3808 * GDB's version number moved to ``version.in''
3810 The Makefile variable VERSION has been replaced by the file
3811 ``version.in''. People creating GDB distributions should update the
3812 contents of this file.
3816 GUD support is now a standard part of the EMACS distribution.
3818 *** Changes in GDB 5.0:
3820 * Improved support for debugging FP programs on x86 targets
3822 Unified and much-improved support for debugging floating-point
3823 programs on all x86 targets. In particular, ``info float'' now
3824 displays the FP registers in the same format on all x86 targets, with
3825 greater level of detail.
3827 * Improvements and bugfixes in hardware-assisted watchpoints
3829 It is now possible to watch array elements, struct members, and
3830 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3831 on x86 targets no longer erroneously trigger when the address is
3834 * Improvements in the native DJGPP version of GDB
3836 The distribution now includes all the scripts and auxiliary files
3837 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3838 machines ``out of the box''.
3840 The DJGPP version can now debug programs that use signals. It is
3841 possible to catch signals that happened in the debuggee, deliver
3842 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3843 would kill the program being debugged.) Programs that hook hardware
3844 interrupts (keyboard, timer, etc.) can also be debugged.
3846 It is now possible to debug DJGPP programs that redirect their
3847 standard handles or switch them to raw (as opposed to cooked) mode, or
3848 even close them. The command ``run < foo > bar'' works as expected,
3849 and ``info terminal'' reports useful information about the debuggee's
3850 terminal, including raw/cooked mode, redirection, etc.
3852 The DJGPP version now uses termios functions for console I/O, which
3853 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3856 DOS-style file names with drive letters are now fully supported by
3859 It is now possible to debug DJGPP programs that switch their working
3860 directory. It is also possible to rerun the debuggee any number of
3861 times without restarting GDB; thus, you can use the same setup,
3862 breakpoints, etc. for many debugging sessions.
3864 * New native configurations
3866 ARM GNU/Linux arm*-*-linux*
3867 PowerPC GNU/Linux powerpc-*-linux*
3871 Motorola MCore mcore-*-*
3872 x86 VxWorks i[3456]86-*-vxworks*
3873 PowerPC VxWorks powerpc-*-vxworks*
3874 TI TMS320C80 tic80-*-*
3876 * OBSOLETE configurations
3878 Altos 3068 m68*-altos-*
3879 Convex c1-*-*, c2-*-*
3881 ARM RISCix arm-*-* (as host)
3884 Configurations that have been declared obsolete will be commented out,
3885 but the code will be left in place. If there is no activity to revive
3886 these configurations before the next release of GDB, the sources will
3887 be permanently REMOVED.
3889 * Gould support removed
3891 Support for the Gould PowerNode and NP1 has been removed.
3893 * New features for SVR4
3895 On SVR4 native platforms (such as Solaris), if you attach to a process
3896 without first loading a symbol file, GDB will now attempt to locate and
3897 load symbols from the running process's executable file.
3899 * Many C++ enhancements
3901 C++ support has been greatly improved. Overload resolution now works properly
3902 in almost all cases. RTTI support is on the way.
3904 * Remote targets can connect to a sub-program
3906 A popen(3) style serial-device has been added. This device starts a
3907 sub-process (such as a stand-alone simulator) and then communicates
3908 with that. The sub-program to run is specified using the syntax
3909 ``|<program> <args>'' vis:
3911 (gdb) set remotedebug 1
3912 (gdb) target extended-remote |mn10300-elf-sim program-args
3914 * MIPS 64 remote protocol
3916 A long standing bug in the mips64 remote protocol where by GDB
3917 expected certain 32 bit registers (ex SR) to be transfered as 32
3918 instead of 64 bits has been fixed.
3920 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3921 added to provide backward compatibility with older versions of GDB.
3923 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3925 The command ``set remotebinarydownload'' command has been replaced by
3926 ``set remote X-packet''. Other commands in ``set remote'' family
3927 include ``set remote P-packet''.
3929 * Breakpoint commands accept ranges.
3931 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3932 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3933 ``tracepoint passcount'' also accepts a range of tracepoints.
3935 * ``apropos'' command added.
3937 The ``apropos'' command searches through command names and
3938 documentation strings, printing out matches, making it much easier to
3939 try to find a command that does what you are looking for.
3943 A new machine oriented interface (MI) has been added to GDB. This
3944 interface is designed for debug environments running GDB as a separate
3945 process. This is part of the long term libGDB project. See the
3946 "GDB/MI" chapter of the GDB manual for further information. It can be
3947 enabled by configuring with:
3949 .../configure --enable-gdbmi
3951 *** Changes in GDB-4.18:
3953 * New native configurations
3955 HP-UX 10.20 hppa*-*-hpux10.20
3956 HP-UX 11.x hppa*-*-hpux11.0*
3957 M68K GNU/Linux m68*-*-linux*
3961 Fujitsu FR30 fr30-*-elf*
3962 Intel StrongARM strongarm-*-*
3963 Mitsubishi D30V d30v-*-*
3965 * OBSOLETE configurations
3967 Gould PowerNode, NP1 np1-*-*, pn-*-*
3969 Configurations that have been declared obsolete will be commented out,
3970 but the code will be left in place. If there is no activity to revive
3971 these configurations before the next release of GDB, the sources will
3972 be permanently REMOVED.
3976 As a compatibility experiment, GDB's source files buildsym.h and
3977 buildsym.c have been converted to pure standard C, no longer
3978 containing any K&R compatibility code. We believe that all systems in
3979 use today either come with a standard C compiler, or have a GCC port
3980 available. If this is not true, please report the affected
3981 configuration to bug-gdb@gnu.org immediately. See the README file for
3982 information about getting a standard C compiler if you don't have one
3987 GDB now uses readline 2.2.
3989 * set extension-language
3991 You can now control the mapping between filename extensions and source
3992 languages by using the `set extension-language' command. For instance,
3993 you can ask GDB to treat .c files as C++ by saying
3994 set extension-language .c c++
3995 The command `info extensions' lists all of the recognized extensions
3996 and their associated languages.
3998 * Setting processor type for PowerPC and RS/6000
4000 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4001 you can use the `set processor' command to specify what variant of the
4002 PowerPC family you are debugging. The command
4006 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4007 following PowerPC and RS6000 variants:
4009 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4010 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4012 403GC IBM PowerPC 403GC
4013 505 Motorola PowerPC 505
4014 860 Motorola PowerPC 860 or 850
4015 601 Motorola PowerPC 601
4016 602 Motorola PowerPC 602
4017 603 Motorola/IBM PowerPC 603 or 603e
4018 604 Motorola PowerPC 604 or 604e
4019 750 Motorola/IBM PowerPC 750 or 750
4021 At the moment, this command just tells GDB what to name the
4022 special-purpose processor registers. Since almost all the affected
4023 registers are inaccessible to user-level programs, this command is
4024 only useful for remote debugging in its present form.
4028 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4029 more extensive support for HP-UX. Added features include shared
4030 library support, kernel threads and hardware watchpoints for 11.00,
4031 support for HP's ANSI C and C++ compilers, and a compatibility mode
4032 for xdb and dbx commands.
4036 HP's donation includes the new concept of catchpoints, which is a
4037 generalization of the old catch command. On HP-UX, it is now possible
4038 to catch exec, fork, and vfork, as well as library loading.
4040 This means that the existing catch command has changed; its first
4041 argument now specifies the type of catch to be set up. See the
4042 output of "help catch" for a list of catchpoint types.
4044 * Debugging across forks
4046 On HP-UX, you can choose which process to debug when a fork() happens
4051 HP has donated a curses-based terminal user interface (TUI). To get
4052 it, build with --enable-tui. Although this can be enabled for any
4053 configuration, at present it only works for native HP debugging.
4055 * GDB remote protocol additions
4057 A new protocol packet 'X' that writes binary data is now available.
4058 Default behavior is to try 'X', then drop back to 'M' if the stub
4059 fails to respond. The settable variable `remotebinarydownload'
4060 allows explicit control over the use of 'X'.
4062 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4063 full 64-bit address. The command
4065 set remoteaddresssize 32
4067 can be used to revert to the old behaviour. For existing remote stubs
4068 the change should not be noticed, as the additional address information
4071 In order to assist in debugging stubs, you may use the maintenance
4072 command `packet' to send any text string to the stub. For instance,
4074 maint packet heythere
4076 sends the packet "$heythere#<checksum>". Note that it is very easy to
4077 disrupt a debugging session by sending the wrong packet at the wrong
4080 The compare-sections command allows you to compare section data on the
4081 target to what is in the executable file without uploading or
4082 downloading, by comparing CRC checksums.
4084 * Tracing can collect general expressions
4086 You may now collect general expressions at tracepoints. This requires
4087 further additions to the target-side stub; see tracepoint.c and
4088 doc/agentexpr.texi for further details.
4090 * mask-address variable for Mips
4092 For Mips targets, you may control the zeroing of the upper 32 bits of
4093 a 64-bit address by entering `set mask-address on'. This is mainly
4094 of interest to users of embedded R4xxx and R5xxx processors.
4096 * Higher serial baud rates
4098 GDB's serial code now allows you to specify baud rates 57600, 115200,
4099 230400, and 460800 baud. (Note that your host system may not be able
4100 to achieve all of these rates.)
4104 The i960 configuration now includes an initial implementation of a
4105 builtin simulator, contributed by Jim Wilson.
4108 *** Changes in GDB-4.17:
4110 * New native configurations
4112 Alpha GNU/Linux alpha*-*-linux*
4113 Unixware 2.x i[3456]86-unixware2*
4114 Irix 6.x mips*-sgi-irix6*
4115 PowerPC GNU/Linux powerpc-*-linux*
4116 PowerPC Solaris powerpcle-*-solaris*
4117 Sparc GNU/Linux sparc-*-linux*
4118 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4122 Argonaut Risc Chip (ARC) arc-*-*
4123 Hitachi H8/300S h8300*-*-*
4124 Matsushita MN10200 w/simulator mn10200-*-*
4125 Matsushita MN10300 w/simulator mn10300-*-*
4126 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4127 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4128 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4129 Mitsubishi D10V w/simulator d10v-*-*
4130 Mitsubishi M32R/D w/simulator m32r-*-elf*
4131 Tsqware Sparclet sparclet-*-*
4132 NEC V850 w/simulator v850-*-*
4134 * New debugging protocols
4136 ARM with RDI protocol arm*-*-*
4137 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4138 DDB and LSI variants of PMON protocol mips*-*-*
4139 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4140 PowerPC with SDS protocol powerpc{,le}-*-eabi
4141 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4145 All configurations can now understand and use the DWARF 2 debugging
4146 format. The choice is automatic, if the symbol file contains DWARF 2
4151 GDB now includes basic Java language support. This support is
4152 only useful with Java compilers that produce native machine code.
4154 * solib-absolute-prefix and solib-search-path
4156 For SunOS and SVR4 shared libraries, you may now set the prefix for
4157 loading absolute shared library symbol files, and the search path for
4158 locating non-absolute shared library symbol files.
4160 * Live range splitting
4162 GDB can now effectively debug code for which GCC has performed live
4163 range splitting as part of its optimization. See gdb/doc/LRS for
4164 more details on the expected format of the stabs information.
4168 GDB's support for the GNU Hurd, including thread debugging, has been
4169 updated to work with current versions of the Hurd.
4173 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4174 instruction set. ARM GDB automatically detects when Thumb
4175 instructions are in use, and adjusts disassembly and backtracing
4180 GDB's MIPS target configurations now handle the MIP16 16-bit
4185 GDB now includes support for overlays; if an executable has been
4186 linked such that multiple sections are based at the same address, GDB
4187 will decide which section to use for symbolic info. You can choose to
4188 control the decision manually, using overlay commands, or implement
4189 additional target-side support and use "overlay load-target" to bring
4190 in the overlay mapping. Do "help overlay" for more detail.
4194 The command "info symbol <address>" displays information about
4195 the symbol at the specified address.
4199 The standard remote protocol now includes an extension that allows
4200 asynchronous collection and display of trace data. This requires
4201 extensive support in the target-side debugging stub. Tracing mode
4202 includes a new interaction mode in GDB and new commands: see the
4203 file tracepoint.c for more details.
4207 Configurations for embedded MIPS now include a simulator contributed
4208 by Cygnus Solutions. The simulator supports the instruction sets
4209 of most MIPS variants.
4213 Sparc configurations may now include the ERC32 simulator contributed
4214 by the European Space Agency. The simulator is not built into
4215 Sparc targets by default; configure with --enable-sim to include it.
4219 For target configurations that may include multiple variants of a
4220 basic architecture (such as MIPS and SH), you may now set the
4221 architecture explicitly. "set arch" sets, "info arch" lists
4222 the possible architectures.
4224 *** Changes in GDB-4.16:
4226 * New native configurations
4228 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4229 M68K NetBSD m68k-*-netbsd*
4230 PowerPC AIX 4.x powerpc-*-aix*
4231 PowerPC MacOS powerpc-*-macos*
4232 PowerPC Windows NT powerpcle-*-cygwin32
4233 RS/6000 AIX 4.x rs6000-*-aix4*
4237 ARM with RDP protocol arm-*-*
4238 I960 with MON960 i960-*-coff
4239 MIPS VxWorks mips*-*-vxworks*
4240 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4241 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4243 Matra Sparclet sparclet-*-*
4247 The powerpc-eabi configuration now includes the PSIM simulator,
4248 contributed by Andrew Cagney, with assistance from Mike Meissner.
4249 PSIM is a very elaborate model of the PowerPC, including not only
4250 basic instruction set execution, but also details of execution unit
4251 performance and I/O hardware. See sim/ppc/README for more details.
4255 GDB now works with Solaris 2.5.
4257 * Windows 95/NT native
4259 GDB will now work as a native debugger on Windows 95 and Windows NT.
4260 To build it from source, you must use the "gnu-win32" environment,
4261 which uses a DLL to emulate enough of Unix to run the GNU tools.
4262 Further information, binaries, and sources are available at
4263 ftp.cygnus.com, under pub/gnu-win32.
4265 * dont-repeat command
4267 If a user-defined command includes the command `dont-repeat', then the
4268 command will not be repeated if the user just types return. This is
4269 useful if the command is time-consuming to run, so that accidental
4270 extra keystrokes don't run the same command many times.
4272 * Send break instead of ^C
4274 The standard remote protocol now includes an option to send a break
4275 rather than a ^C to the target in order to interrupt it. By default,
4276 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4278 * Remote protocol timeout
4280 The standard remote protocol includes a new variable `remotetimeout'
4281 that allows you to set the number of seconds before GDB gives up trying
4282 to read from the target. The default value is 2.
4284 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4286 By default GDB will automatically keep track of objects as they are
4287 loaded and unloaded by the dynamic linker. By using the command `set
4288 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4289 when shared library events occur, thus allowing you to set breakpoints
4290 in shared libraries which are explicitly loaded by the inferior.
4292 Note this feature does not work on hpux8. On hpux9 you must link
4293 /usr/lib/end.o into your program. This feature should work
4294 automatically on hpux10.
4296 * Irix 5.x hardware watchpoint support
4298 Irix 5 configurations now support the use of hardware watchpoints.
4300 * Mips protocol "SYN garbage limit"
4302 When debugging a Mips target using the `target mips' protocol, you
4303 may set the number of characters that GDB will ignore by setting
4304 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4305 every character. The default value is 1050.
4307 * Recording and replaying remote debug sessions
4309 If you set `remotelogfile' to the name of a file, gdb will write to it
4310 a recording of a remote debug session. This recording may then be
4311 replayed back to gdb using "gdbreplay". See gdbserver/README for
4312 details. This is useful when you have a problem with GDB while doing
4313 remote debugging; you can make a recording of the session and send it
4314 to someone else, who can then recreate the problem.
4316 * Speedups for remote debugging
4318 GDB includes speedups for downloading and stepping MIPS systems using
4319 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4320 and more efficient S-record downloading.
4322 * Memory use reductions and statistics collection
4324 GDB now uses less memory and reports statistics about memory usage.
4325 Try the `maint print statistics' command, for example.
4327 *** Changes in GDB-4.15:
4329 * Psymtabs for XCOFF
4331 The symbol reader for AIX GDB now uses partial symbol tables. This
4332 can greatly improve startup time, especially for large executables.
4334 * Remote targets use caching
4336 Remote targets now use a data cache to speed up communication with the
4337 remote side. The data cache could lead to incorrect results because
4338 it doesn't know about volatile variables, thus making it impossible to
4339 debug targets which use memory mapped I/O devices. `set remotecache
4340 off' turns the the data cache off.
4342 * Remote targets may have threads
4344 The standard remote protocol now includes support for multiple threads
4345 in the target system, using new protocol commands 'H' and 'T'. See
4346 gdb/remote.c for details.
4350 If GDB is configured with `--enable-netrom', then it will include
4351 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4352 acts as though it is a bank of ROM on the target board, but you can
4353 write into it over the network. GDB's support consists only of
4354 support for fast loading into the emulated ROM; to debug, you must use
4355 another protocol, such as standard remote protocol. The usual
4356 sequence is something like
4358 target nrom <netrom-hostname>
4360 target remote <netrom-hostname>:1235
4364 GDB now includes support for the Apple Macintosh, as a host only. It
4365 may be run as either an MPW tool or as a standalone application, and
4366 it can debug through the serial port. All the usual GDB commands are
4367 available, but to the target command, you must supply "serial" as the
4368 device type instead of "/dev/ttyXX". See mpw-README in the main
4369 directory for more information on how to build. The MPW configuration
4370 scripts */mpw-config.in support only a few targets, and only the
4371 mips-idt-ecoff target has been tested.
4375 GDB configuration now uses autoconf. This is not user-visible,
4376 but does simplify configuration and building.
4380 GDB now supports hpux10.
4382 *** Changes in GDB-4.14:
4384 * New native configurations
4386 x86 FreeBSD i[345]86-*-freebsd
4387 x86 NetBSD i[345]86-*-netbsd
4388 NS32k NetBSD ns32k-*-netbsd
4389 Sparc NetBSD sparc-*-netbsd
4393 A29K VxWorks a29k-*-vxworks
4394 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4395 CPU32 EST-300 emulator m68*-*-est*
4396 PowerPC ELF powerpc-*-elf
4399 * Alpha OSF/1 support for procfs
4401 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4402 possible to attach to running processes. As the mounting of the /proc
4403 filesystem is optional on the Alpha, GDB automatically determines
4404 the availability of /proc during startup. This can lead to problems
4405 if /proc is unmounted after GDB has been started.
4407 * Arguments to user-defined commands
4409 User commands may accept up to 10 arguments separated by whitespace.
4410 Arguments are accessed within the user command via $arg0..$arg9. A
4413 print $arg0 + $arg1 + $arg2
4415 To execute the command use:
4418 Defines the command "adder" which prints the sum of its three arguments.
4419 Note the arguments are text substitutions, so they may reference variables,
4420 use complex expressions, or even perform inferior function calls.
4422 * New `if' and `while' commands
4424 This makes it possible to write more sophisticated user-defined
4425 commands. Both commands take a single argument, which is the
4426 expression to evaluate, and must be followed by the commands to
4427 execute, one per line, if the expression is nonzero, the list being
4428 terminated by the word `end'. The `if' command list may include an
4429 `else' word, which causes the following commands to be executed only
4430 if the expression is zero.
4432 * Fortran source language mode
4434 GDB now includes partial support for Fortran 77. It will recognize
4435 Fortran programs and can evaluate a subset of Fortran expressions, but
4436 variables and functions may not be handled correctly. GDB will work
4437 with G77, but does not yet know much about symbols emitted by other
4440 * Better HPUX support
4442 Most debugging facilities now work on dynamic executables for HPPAs
4443 running hpux9 or later. You can attach to running dynamically linked
4444 processes, but by default the dynamic libraries will be read-only, so
4445 for instance you won't be able to put breakpoints in them. To change
4446 that behavior do the following before running the program:
4452 This will cause the libraries to be mapped private and read-write.
4453 To revert to the normal behavior, do this:
4459 You cannot set breakpoints or examine data in the library until after
4460 the library is loaded if the function/data symbols do not have
4463 GDB can now also read debug symbols produced by the HP C compiler on
4464 HPPAs (sorry, no C++, Fortran or 68k support).
4466 * Target byte order now dynamically selectable
4468 You can choose which byte order to use with a target system, via the
4469 commands "set endian big" and "set endian little", and you can see the
4470 current setting by using "show endian". You can also give the command
4471 "set endian auto", in which case GDB will use the byte order
4472 associated with the executable. Currently, only embedded MIPS
4473 configurations support dynamic selection of target byte order.
4475 * New DOS host serial code
4477 This version uses DPMI interrupts to handle buffered I/O, so you
4478 no longer need to run asynctsr when debugging boards connected to
4481 *** Changes in GDB-4.13:
4483 * New "complete" command
4485 This lists all the possible completions for the rest of the line, if it
4486 were to be given as a command itself. This is intended for use by emacs.
4488 * Trailing space optional in prompt
4490 "set prompt" no longer adds a space for you after the prompt you set. This
4491 allows you to set a prompt which ends in a space or one that does not.
4493 * Breakpoint hit counts
4495 "info break" now displays a count of the number of times the breakpoint
4496 has been hit. This is especially useful in conjunction with "ignore"; you
4497 can ignore a large number of breakpoint hits, look at the breakpoint info
4498 to see how many times the breakpoint was hit, then run again, ignoring one
4499 less than that number, and this will get you quickly to the last hit of
4502 * Ability to stop printing at NULL character
4504 "set print null-stop" will cause GDB to stop printing the characters of
4505 an array when the first NULL is encountered. This is useful when large
4506 arrays actually contain only short strings.
4508 * Shared library breakpoints
4510 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4511 breakpoints in shared libraries before the executable is run.
4513 * Hardware watchpoints
4515 There is a new hardware breakpoint for the watch command for sparclite
4516 targets. See gdb/sparclite/hw_breakpoint.note.
4518 Hardware watchpoints are also now supported under GNU/Linux.
4522 Annotations have been added. These are for use with graphical interfaces,
4523 and are still experimental. Currently only gdba.el uses these.
4525 * Improved Irix 5 support
4527 GDB now works properly with Irix 5.2.
4529 * Improved HPPA support
4531 GDB now works properly with the latest GCC and GAS.
4533 * New native configurations
4535 Sequent PTX4 i[34]86-sequent-ptx4
4536 HPPA running OSF/1 hppa*-*-osf*
4537 Atari TT running SVR4 m68*-*-sysv4*
4538 RS/6000 LynxOS rs6000-*-lynxos*
4542 OS/9000 i[34]86-*-os9k
4543 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4546 * Hitachi SH7000 and E7000-PC ICE support
4548 There is now support for communicating with the Hitachi E7000-PC ICE.
4549 This is available automatically when GDB is configured for the SH.
4553 As usual, a variety of small fixes and improvements, both generic
4554 and configuration-specific. See the ChangeLog for more detail.
4556 *** Changes in GDB-4.12:
4558 * Irix 5 is now supported
4562 GDB-4.12 on the HPPA has a number of changes which make it unable
4563 to debug the output from the currently released versions of GCC and
4564 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4565 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4566 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4569 *** Changes in GDB-4.11:
4571 * User visible changes:
4575 The "set remotedebug" option is now consistent between the mips remote
4576 target, remote targets using the gdb-specific protocol, UDI (AMD's
4577 debug protocol for the 29k) and the 88k bug monitor. It is now an
4578 integer specifying a debug level (normally 0 or 1, but 2 means more
4579 debugging info for the mips target).
4581 * DEC Alpha native support
4583 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4584 debug info, but GDB works fairly well with the DEC compiler and should
4585 work with a future GCC release. See the README file for a few
4586 Alpha-specific notes.
4588 * Preliminary thread implementation
4590 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4592 * LynxOS native and target support for 386
4594 This release has been hosted on LynxOS 2.2, and also can be configured
4595 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4598 * Improvements in C++ mangling/demangling.
4600 This release has much better g++ debugging, specifically in name
4601 mangling/demangling, virtual function calls, print virtual table,
4602 call methods, ...etc.
4604 *** Changes in GDB-4.10:
4606 * User visible changes:
4608 Remote debugging using the GDB-specific (`target remote') protocol now
4609 supports the `load' command. This is only useful if you have some
4610 other way of getting the stub to the target system, and you can put it
4611 somewhere in memory where it won't get clobbered by the download.
4613 Filename completion now works.
4615 When run under emacs mode, the "info line" command now causes the
4616 arrow to point to the line specified. Also, "info line" prints
4617 addresses in symbolic form (as well as hex).
4619 All vxworks based targets now support a user settable option, called
4620 vxworks-timeout. This option represents the number of seconds gdb
4621 should wait for responses to rpc's. You might want to use this if
4622 your vxworks target is, perhaps, a slow software simulator or happens
4623 to be on the far side of a thin network line.
4627 This release contains support for using a DEC alpha as a GDB host for
4628 cross debugging. Native alpha debugging is not supported yet.
4631 *** Changes in GDB-4.9:
4635 This is the first GDB release which is accompanied by a matching testsuite.
4636 The testsuite requires installation of dejagnu, which should be available
4637 via ftp from most sites that carry GNU software.
4641 'Cfront' style demangling has had its name changed to 'ARM' style, to
4642 emphasize that it was written from the specifications in the C++ Annotated
4643 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4644 disclaimers, it still generated too much confusion with users attempting to
4645 use gdb with AT&T cfront.
4649 GDB now uses a standard remote interface to a simulator library.
4650 So far, the library contains simulators for the Zilog Z8001/2, the
4651 Hitachi H8/300, H8/500 and Super-H.
4653 * New targets supported
4655 H8/300 simulator h8300-hitachi-hms or h8300hms
4656 H8/500 simulator h8500-hitachi-hms or h8500hms
4657 SH simulator sh-hitachi-hms or sh
4658 Z8000 simulator z8k-zilog-none or z8ksim
4659 IDT MIPS board over serial line mips-idt-ecoff
4661 Cross-debugging to GO32 targets is supported. It requires a custom
4662 version of the i386-stub.c module which is integrated with the
4663 GO32 memory extender.
4665 * New remote protocols
4667 MIPS remote debugging protocol.
4669 * New source languages supported
4671 This version includes preliminary support for Chill, a Pascal like language
4672 used by telecommunications companies. Chill support is also being integrated
4673 into the GNU compiler, but we don't know when it will be publically available.
4676 *** Changes in GDB-4.8:
4678 * HP Precision Architecture supported
4680 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4681 version of this support was available as a set of patches from the
4682 University of Utah. GDB does not support debugging of programs
4683 compiled with the HP compiler, because HP will not document their file
4684 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4685 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4687 Many problems in the preliminary version have been fixed.
4689 * Faster and better demangling
4691 We have improved template demangling and fixed numerous bugs in the GNU style
4692 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4693 character types (wchar_t) are now supported. Demangling of each symbol is now
4694 only done once, and is cached when the symbol table for a file is read in.
4695 This results in a small increase in memory usage for C programs, a moderate
4696 increase in memory usage for C++ programs, and a fantastic speedup in
4699 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4700 from the specifications in the Annotated Reference Manual, which AT&T's
4701 compiler does not actually implement.
4703 * G++ multiple inheritance compiler problem
4705 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4706 inheritance lattices was reworked to properly discover ambiguities. We
4707 recently found an example which causes this new algorithm to fail in a
4708 very subtle way, producing bad debug information for those classes.
4709 The file 'gcc.patch' (in this directory) can be applied to gcc to
4710 circumvent the problem. A future GCC release will contain a complete
4713 The previous G++ debug info problem (mentioned below for the gdb-4.7
4714 release) is fixed in gcc version 2.3.2.
4716 * Improved configure script
4718 The `configure' script will now attempt to guess your system type if
4719 you don't supply a host system type. The old scheme of supplying a
4720 host system triplet is preferable over using this. All the magic is
4721 done in the new `config.guess' script. Examine it for details.
4723 We have also brought our configure script much more in line with the FSF's
4724 version. It now supports the --with-xxx options. In particular,
4725 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4726 The resulting GDB will not be able to read arbitrary object file formats --
4727 only the format ``expected'' to be used on the configured target system.
4728 We hope to make this the default in a future release.
4730 * Documentation improvements
4732 There's new internal documentation on how to modify GDB, and how to
4733 produce clean changes to the code. We implore people to read it
4734 before submitting changes.
4736 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4737 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4738 `info' files are also provided. To build `info' files from scratch,
4739 you will need the latest `makeinfo' release, which will be available in
4740 a future texinfo-X.Y release.
4742 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4743 We're not sure exactly which versions have this problem, but it has
4744 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4745 or better. If that isn't possible, there is a patch in
4746 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4747 around this problem.
4751 GDB now supports array constants that can be used in expressions typed in by
4752 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4753 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4756 The new directory `gdb/sparclite' contains a program that demonstrates
4757 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4759 * New native hosts supported
4761 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4762 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4764 * New targets supported
4766 AMD 29k family via UDI a29k-amd-udi or udi29k
4768 * New file formats supported
4770 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4771 HPUX core files, and SCO 3.2v2 core files.
4775 Attaching to processes now works again; thanks for the many bug reports.
4777 We have also stomped on a bunch of core dumps caused by
4778 printf_filtered("%s") problems.
4780 We eliminated a copyright problem on the rpc and ptrace header files
4781 for VxWorks, which was discovered at the last minute during the 4.7
4782 release. You should now be able to build a VxWorks GDB.
4784 You can now interrupt gdb while an attached process is running. This
4785 will cause the attached process to stop, and give control back to GDB.
4787 We fixed problems caused by using too many file descriptors
4788 for reading symbols from object files and libraries. This was
4789 especially a problem for programs that used many (~100) shared
4792 The `step' command now only enters a subroutine if there is line number
4793 information for the subroutine. Otherwise it acts like the `next'
4794 command. Previously, `step' would enter subroutines if there was
4795 any debugging information about the routine. This avoids problems
4796 when using `cc -g1' on MIPS machines.
4798 * Internal improvements
4800 GDB's internal interfaces have been improved to make it easier to support
4801 debugging of multiple languages in the future.
4803 GDB now uses a common structure for symbol information internally.
4804 Minimal symbols (derived from linkage symbols in object files), partial
4805 symbols (from a quick scan of debug information), and full symbols
4806 contain a common subset of information, making it easier to write
4807 shared code that handles any of them.
4809 * New command line options
4811 We now accept --silent as an alias for --quiet.
4815 The memory-mapped-malloc library is now licensed under the GNU Library
4816 General Public License.
4818 *** Changes in GDB-4.7:
4820 * Host/native/target split
4822 GDB has had some major internal surgery to untangle the support for
4823 hosts and remote targets. Now, when you configure GDB for a remote
4824 target, it will no longer load in all of the support for debugging
4825 local programs on the host. When fully completed and tested, this will
4826 ensure that arbitrary host/target combinations are possible.
4828 The primary conceptual shift is to separate the non-portable code in
4829 GDB into three categories. Host specific code is required any time GDB
4830 is compiled on that host, regardless of the target. Target specific
4831 code relates to the peculiarities of the target, but can be compiled on
4832 any host. Native specific code is everything else: it can only be
4833 built when the host and target are the same system. Child process
4834 handling and core file support are two common `native' examples.
4836 GDB's use of /proc for controlling Unix child processes is now cleaner.
4837 It has been split out into a single module under the `target_ops' vector,
4838 plus two native-dependent functions for each system that uses /proc.
4840 * New hosts supported
4842 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4843 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4844 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4846 * New targets supported
4848 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4849 68030 and CPU32 m68030-*-*, m68332-*-*
4851 * New native hosts supported
4853 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4854 (386bsd is not well tested yet)
4855 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4857 * New file formats supported
4859 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4860 supports reading of `a.out.adobe' object files, which are an a.out
4861 format extended with minimal information about multiple sections.
4865 `show copying' is the same as the old `info copying'.
4866 `show warranty' is the same as `info warrantee'.
4867 These were renamed for consistency. The old commands continue to work.
4869 `info handle' is a new alias for `info signals'.
4871 You can now define pre-command hooks, which attach arbitrary command
4872 scripts to any command. The commands in the hook will be executed
4873 prior to the user's command. You can also create a hook which will be
4874 executed whenever the program stops. See gdb.texinfo.
4878 We now deal with Cfront style name mangling, and can even extract type
4879 info from mangled symbols. GDB can automatically figure out which
4880 symbol mangling style your C++ compiler uses.
4882 Calling of methods and virtual functions has been improved as well.
4886 The crash that occured when debugging Sun Ansi-C compiled binaries is
4887 fixed. This was due to mishandling of the extra N_SO stabs output
4890 We also finally got Ultrix 4.2 running in house, and fixed core file
4891 support, with help from a dozen people on the net.
4893 John M. Farrell discovered that the reason that single-stepping was so
4894 slow on all of the Mips based platforms (primarily SGI and DEC) was
4895 that we were trying to demangle and lookup a symbol used for internal
4896 purposes on every instruction that was being stepped through. Changing
4897 the name of that symbol so that it couldn't be mistaken for a C++
4898 mangled symbol sped things up a great deal.
4900 Rich Pixley sped up symbol lookups in general by getting much smarter
4901 about when C++ symbol mangling is necessary. This should make symbol
4902 completion (TAB on the command line) much faster. It's not as fast as
4903 we'd like, but it's significantly faster than gdb-4.6.
4907 A new user controllable variable 'call_scratch_address' can
4908 specify the location of a scratch area to be used when GDB
4909 calls a function in the target. This is necessary because the
4910 usual method of putting the scratch area on the stack does not work
4911 in systems that have separate instruction and data spaces.
4913 We integrated changes to support the 29k UDI (Universal Debugger
4914 Interface), but discovered at the last minute that we didn't have all
4915 of the appropriate copyright paperwork. We are working with AMD to
4916 resolve this, and hope to have it available soon.
4920 We have sped up the remote serial line protocol, especially for targets
4921 with lots of registers. It now supports a new `expedited status' ('T')
4922 message which can be used in place of the existing 'S' status message.
4923 This allows the remote stub to send only the registers that GDB
4924 needs to make a quick decision about single-stepping or conditional
4925 breakpoints, eliminating the need to fetch the entire register set for
4926 each instruction being stepped through.
4928 The GDB remote serial protocol now implements a write-through cache for
4929 registers, only re-reading the registers if the target has run.
4931 There is also a new remote serial stub for SPARC processors. You can
4932 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4933 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4934 processor with a serial port.
4938 Configure.in files have become much easier to read and modify. A new
4939 `table driven' format makes it more obvious what configurations are
4940 supported, and what files each one uses.
4944 There is a new opcodes library which will eventually contain all of the
4945 disassembly routines and opcode tables. At present, it only contains
4946 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4947 disassembler (binutils/objdump) to share these routines.
4949 The libiberty library is now copylefted under the GNU Library General
4950 Public License. This allows more liberal use, and was done so libg++
4951 can use it. This makes no difference to GDB, since the Library License
4952 grants all the rights from the General Public License.
4956 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4957 reference to the stabs symbol info used by the debugger. It is (as far
4958 as we know) the only published document on this fascinating topic. We
4959 encourage you to read it, compare it to the stabs information on your
4960 system, and send improvements on the document in general (to
4961 bug-gdb@prep.ai.mit.edu).
4963 And, of course, many bugs have been fixed.
4966 *** Changes in GDB-4.6:
4968 * Better support for C++ function names
4970 GDB now accepts as input the "demangled form" of C++ overloaded function
4971 names and member function names, and can do command completion on such names
4972 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4973 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4974 Make use of command completion, it is your friend.
4976 GDB also now accepts a variety of C++ mangled symbol formats. They are
4977 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4978 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4979 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4980 for the list of formats.
4982 * G++ symbol mangling problem
4984 Recent versions of gcc have a bug in how they emit debugging information for
4985 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4986 directory) can be applied to gcc to fix the problem. Alternatively, if you
4987 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4988 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4989 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4992 * New 'maintenance' command
4994 All of the commands related to hacking GDB internals have been moved out of
4995 the main command set, and now live behind the 'maintenance' command. This
4996 can also be abbreviated as 'mt'. The following changes were made:
4998 dump-me -> maintenance dump-me
4999 info all-breakpoints -> maintenance info breakpoints
5000 printmsyms -> maintenance print msyms
5001 printobjfiles -> maintenance print objfiles
5002 printpsyms -> maintenance print psymbols
5003 printsyms -> maintenance print symbols
5005 The following commands are new:
5007 maintenance demangle Call internal GDB demangler routine to
5008 demangle a C++ link name and prints the result.
5009 maintenance print type Print a type chain for a given symbol
5011 * Change to .gdbinit file processing
5013 We now read the $HOME/.gdbinit file before processing the argv arguments
5014 (e.g. reading symbol files or core files). This allows global parameters to
5015 be set, which will apply during the symbol reading. The ./.gdbinit is still
5016 read after argv processing.
5018 * New hosts supported
5020 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5022 GNU/Linux support i386-unknown-linux or linux
5024 We are also including code to support the HP/PA running BSD and HPUX. This
5025 is almost guaranteed not to work, as we didn't have time to test or build it
5026 for this release. We are including it so that the more adventurous (or
5027 masochistic) of you can play with it. We also had major problems with the
5028 fact that the compiler that we got from HP doesn't support the -g option.
5031 * New targets supported
5033 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5035 * More smarts about finding #include files
5037 GDB now remembers the compilation directory for all include files, and for
5038 all files from which C is generated (like yacc and lex sources). This
5039 greatly improves GDB's ability to find yacc/lex sources, and include files,
5040 especially if you are debugging your program from a directory different from
5041 the one that contains your sources.
5043 We also fixed a bug which caused difficulty with listing and setting
5044 breakpoints in include files which contain C code. (In the past, you had to
5045 try twice in order to list an include file that you hadn't looked at before.)
5047 * Interesting infernals change
5049 GDB now deals with arbitrary numbers of sections, where the symbols for each
5050 section must be relocated relative to that section's landing place in the
5051 target's address space. This work was needed to support ELF with embedded
5052 stabs used by Solaris-2.0.
5054 * Bug fixes (of course!)
5056 There have been loads of fixes for the following things:
5057 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5058 i960, stabs, DOS(GO32), procfs, etc...
5060 See the ChangeLog for details.
5062 *** Changes in GDB-4.5:
5064 * New machines supported (host and target)
5066 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5068 SGI Irix-4.x mips-sgi-irix4 or iris4
5070 * New malloc package
5072 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5073 Mmalloc is capable of handling mutiple heaps of memory. It is also
5074 capable of saving a heap to a file, and then mapping it back in later.
5075 This can be used to greatly speedup the startup of GDB by using a
5076 pre-parsed symbol table which lives in a mmalloc managed heap. For
5077 more details, please read mmalloc/mmalloc.texi.
5081 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5082 'help info proc' for details.
5084 * MIPS ecoff symbol table format
5086 The code that reads MIPS symbol table format is now supported on all hosts.
5087 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5090 * File name changes for MS-DOS
5092 Many files in the config directories have been renamed to make it easier to
5093 support GDB on MS-DOSe systems (which have very restrictive file name
5094 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5095 environment) is close to working but has some remaining problems. Note
5096 that debugging of DOS programs is not supported, due to limitations
5097 in the ``operating system'', but it can be used to host cross-debugging.
5099 * Cross byte order fixes
5101 Many fixes have been made to support cross debugging of Sparc and MIPS
5102 targets from hosts whose byte order differs.
5104 * New -mapped and -readnow options
5106 If memory-mapped files are available on your system through the 'mmap'
5107 system call, you can use the -mapped option on the `file' or
5108 `symbol-file' commands to cause GDB to write the symbols from your
5109 program into a reusable file. If the program you are debugging is
5110 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5111 Future GDB debugging sessions will notice the presence of this file,
5112 and will quickly map in symbol information from it, rather than reading
5113 the symbol table from the executable program. Using the '-mapped'
5114 option in a GDB `file' or `symbol-file' command has the same effect as
5115 starting GDB with the '-mapped' command-line option.
5117 You can cause GDB to read the entire symbol table immediately by using
5118 the '-readnow' option with any of the commands that load symbol table
5119 information (or on the GDB command line). This makes the command
5120 slower, but makes future operations faster.
5122 The -mapped and -readnow options are typically combined in order to
5123 build a `fred.syms' file that contains complete symbol information.
5124 A simple GDB invocation to do nothing but build a `.syms' file for future
5127 gdb -batch -nx -mapped -readnow programname
5129 The `.syms' file is specific to the host machine on which GDB is run.
5130 It holds an exact image of GDB's internal symbol table. It cannot be
5131 shared across multiple host platforms.
5133 * longjmp() handling
5135 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5136 siglongjmp() without losing control. This feature has not yet been ported to
5137 all systems. It currently works on many 386 platforms, all MIPS-based
5138 platforms (SGI, DECstation, etc), and Sun3/4.
5142 Preliminary work has been put in to support the new Solaris OS from Sun. At
5143 this time, it can control and debug processes, but it is not capable of
5148 As always, many many bug fixes. The major areas were with g++, and mipsread.
5149 People using the MIPS-based platforms should experience fewer mysterious
5150 crashes and trashed symbol tables.
5152 *** Changes in GDB-4.4:
5154 * New machines supported (host and target)
5156 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5158 BSD Reno on Vax vax-dec-bsd
5159 Ultrix on Vax vax-dec-ultrix
5161 * New machines supported (target)
5163 AMD 29000 embedded, using EBMON a29k-none-none
5167 GDB continues to improve its handling of C++. `References' work better.
5168 The demangler has also been improved, and now deals with symbols mangled as
5169 per the Annotated C++ Reference Guide.
5171 GDB also now handles `stabs' symbol information embedded in MIPS
5172 `ecoff' symbol tables. Since the ecoff format was not easily
5173 extensible to handle new languages such as C++, this appeared to be a
5174 good way to put C++ debugging info into MIPS binaries. This option
5175 will be supported in the GNU C compiler, version 2, when it is
5178 * New features for SVR4
5180 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5181 shared libraries. Debugging dynamically linked programs should present
5182 only minor differences from debugging statically linked programs.
5184 The `info proc' command will print out information about any process
5185 on an SVR4 system (including the one you are debugging). At the moment,
5186 it prints the address mappings of the process.
5188 If you bring up GDB on another SVR4 system, please send mail to
5189 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5191 * Better dynamic linking support in SunOS
5193 Reading symbols from shared libraries which contain debugging symbols
5194 now works properly. However, there remain issues such as automatic
5195 skipping of `transfer vector' code during function calls, which
5196 make it harder to debug code in a shared library, than to debug the
5197 same code linked statically.
5201 GDB is now using the latest `getopt' routines from the FSF. This
5202 version accepts the -- prefix for options with long names. GDB will
5203 continue to accept the old forms (-option and +option) as well.
5204 Various single letter abbreviations for options have been explicity
5205 added to the option table so that they won't get overshadowed in the
5206 future by other options that begin with the same letter.
5210 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5211 Many assorted bugs have been handled. Many more remain to be handled.
5212 See the various ChangeLog files (primarily in gdb and bfd) for details.
5215 *** Changes in GDB-4.3:
5217 * New machines supported (host and target)
5219 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5220 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5221 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5223 * Almost SCO Unix support
5225 We had hoped to support:
5226 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5227 (except for core file support), but we discovered very late in the release
5228 that it has problems with process groups that render gdb unusable. Sorry
5229 about that. I encourage people to fix it and post the fixes.
5231 * Preliminary ELF and DWARF support
5233 GDB can read ELF object files on System V Release 4, and can handle
5234 debugging records for C, in DWARF format, in ELF files. This support
5235 is preliminary. If you bring up GDB on another SVR4 system, please
5236 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5241 GDB now uses the latest `readline' library. One user-visible change
5242 is that two tabs will list possible command completions, which previously
5243 required typing M-? (meta-question mark, or ESC ?).
5247 The `stepi' bug that many of you noticed has been squashed.
5248 Many bugs in C++ have been handled. Many more remain to be handled.
5249 See the various ChangeLog files (primarily in gdb and bfd) for details.
5251 * State of the MIPS world (in case you wondered):
5253 GDB can understand the symbol tables emitted by the compilers
5254 supplied by most vendors of MIPS-based machines, including DEC. These
5255 symbol tables are in a format that essentially nobody else uses.
5257 Some versions of gcc come with an assembler post-processor called
5258 mips-tfile. This program is required if you want to do source-level
5259 debugging of gcc-compiled programs. I believe FSF does not ship
5260 mips-tfile with gcc version 1, but it will eventually come with gcc
5263 Debugging of g++ output remains a problem. g++ version 1.xx does not
5264 really support it at all. (If you're lucky, you should be able to get
5265 line numbers and stack traces to work, but no parameters or local
5266 variables.) With some work it should be possible to improve the
5269 When gcc version 2 is released, you will have somewhat better luck.
5270 However, even then you will get confusing results for inheritance and
5273 We will eventually provide full debugging of g++ output on
5274 DECstations. This will probably involve some kind of stabs-in-ecoff
5275 encapulation, but the details have not been worked out yet.
5278 *** Changes in GDB-4.2:
5280 * Improved configuration
5282 Only one copy of `configure' exists now, and it is not self-modifying.
5283 Porting BFD is simpler.
5287 The `step' and `next' commands now only stop at the first instruction
5288 of a source line. This prevents the multiple stops that used to occur
5289 in switch statements, for-loops, etc. `Step' continues to stop if a
5290 function that has debugging information is called within the line.
5294 Lots of small bugs fixed. More remain.
5296 * New host supported (not target)
5298 Intel 386 PC clone running Mach i386-none-mach
5301 *** Changes in GDB-4.1:
5303 * Multiple source language support
5305 GDB now has internal scaffolding to handle several source languages.
5306 It determines the type of each source file from its filename extension,
5307 and will switch expression parsing and number formatting to match the
5308 language of the function in the currently selected stack frame.
5309 You can also specifically set the language to be used, with
5310 `set language c' or `set language modula-2'.
5314 GDB now has preliminary support for the GNU Modula-2 compiler,
5315 currently under development at the State University of New York at
5316 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5317 continue through the fall of 1991 and into 1992.
5319 Other Modula-2 compilers are currently not supported, and attempting to
5320 debug programs compiled with them will likely result in an error as the
5321 symbol table is read. Feel free to work on it, though!
5323 There are hooks in GDB for strict type checking and range checking,
5324 in the `Modula-2 philosophy', but they do not currently work.
5328 GDB can now write to executable and core files (e.g. patch
5329 a variable's value). You must turn this switch on, specify
5330 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5331 by assigning a new value to a variable. Modifications take
5334 * Automatic SunOS shared library reading
5336 When you run your program, GDB automatically determines where its
5337 shared libraries (if any) have been loaded, and reads their symbols.
5338 The `share' command is no longer needed. This also works when
5339 examining core files.
5343 You can specify the number of lines that the `list' command shows.
5346 * New machines supported (host and target)
5348 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5349 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5350 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5352 * New hosts supported (not targets)
5354 IBM RT/PC: romp-ibm-aix or rtpc
5356 * New targets supported (not hosts)
5358 AMD 29000 embedded with COFF a29k-none-coff
5359 AMD 29000 embedded with a.out a29k-none-aout
5360 Ultracomputer remote kernel debug a29k-nyu-kern
5362 * New remote interfaces
5368 *** Changes in GDB-4.0:
5372 Wide output is wrapped at good places to make the output more readable.
5374 Gdb now supports cross-debugging from a host machine of one type to a
5375 target machine of another type. Communication with the target system
5376 is over serial lines. The ``target'' command handles connecting to the
5377 remote system; the ``load'' command will download a program into the
5378 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5379 also supports debugging of realtime processes running under VxWorks,
5380 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5381 stub on the target system.
5383 New CPUs supported include the AMD 29000 and Intel 960.
5385 GDB now reads object files and symbol tables via a ``binary file''
5386 library, which allows a single copy of GDB to debug programs of multiple
5387 object file types such as a.out and coff.
5389 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5390 refcard.dvi and refcard.ps are available to format it).
5393 * Control-Variable user interface simplified
5395 All variables that control the operation of the debugger can be set
5396 by the ``set'' command, and displayed by the ``show'' command.
5398 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5399 ``Show prompt'' produces the response:
5400 Gdb's prompt is new-gdb=>.
5402 What follows are the NEW set commands. The command ``help set'' will
5403 print a complete list of old and new set commands. ``help set FOO''
5404 will give a longer description of the variable FOO. ``show'' will show
5405 all of the variable descriptions and their current settings.
5407 confirm on/off: Enables warning questions for operations that are
5408 hard to recover from, e.g. rerunning the program while
5409 it is already running. Default is ON.
5411 editing on/off: Enables EMACS style command line editing
5412 of input. Previous lines can be recalled with
5413 control-P, the current line can be edited with control-B,
5414 you can search for commands with control-R, etc.
5417 history filename NAME: NAME is where the gdb command history
5418 will be stored. The default is .gdb_history,
5419 or the value of the environment variable
5422 history size N: The size, in commands, of the command history. The
5423 default is 256, or the value of the environment variable
5426 history save on/off: If this value is set to ON, the history file will
5427 be saved after exiting gdb. If set to OFF, the
5428 file will not be saved. The default is OFF.
5430 history expansion on/off: If this value is set to ON, then csh-like
5431 history expansion will be performed on
5432 command line input. The default is OFF.
5434 radix N: Sets the default radix for input and output. It can be set
5435 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5436 in the current radix, so "set radix 10" is always a no-op.
5438 height N: This integer value is the number of lines on a page. Default
5439 is 24, the current `stty rows'' setting, or the ``li#''
5440 setting from the termcap entry matching the environment
5443 width N: This integer value is the number of characters on a line.
5444 Default is 80, the current `stty cols'' setting, or the ``co#''
5445 setting from the termcap entry matching the environment
5448 Note: ``set screensize'' is obsolete. Use ``set height'' and
5449 ``set width'' instead.
5451 print address on/off: Print memory addresses in various command displays,
5452 such as stack traces and structure values. Gdb looks
5453 more ``symbolic'' if you turn this off; it looks more
5454 ``machine level'' with it on. Default is ON.
5456 print array on/off: Prettyprint arrays. New convenient format! Default
5459 print demangle on/off: Print C++ symbols in "source" form if on,
5462 print asm-demangle on/off: Same, for assembler level printouts
5465 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5468 * Support for Epoch Environment.
5470 The epoch environment is a version of Emacs v18 with windowing. One
5471 new command, ``inspect'', is identical to ``print'', except that if you
5472 are running in the epoch environment, the value is printed in its own
5476 * Support for Shared Libraries
5478 GDB can now debug programs and core files that use SunOS shared libraries.
5479 Symbols from a shared library cannot be referenced
5480 before the shared library has been linked with the program (this
5481 happens after you type ``run'' and before the function main() is entered).
5482 At any time after this linking (including when examining core files
5483 from dynamically linked programs), gdb reads the symbols from each
5484 shared library when you type the ``sharedlibrary'' command.
5485 It can be abbreviated ``share''.
5487 sharedlibrary REGEXP: Load shared object library symbols for files
5488 matching a unix regular expression. No argument
5489 indicates to load symbols for all shared libraries.
5491 info sharedlibrary: Status of loaded shared libraries.
5496 A watchpoint stops execution of a program whenever the value of an
5497 expression changes. Checking for this slows down execution
5498 tremendously whenever you are in the scope of the expression, but is
5499 quite useful for catching tough ``bit-spreader'' or pointer misuse
5500 problems. Some machines such as the 386 have hardware for doing this
5501 more quickly, and future versions of gdb will use this hardware.
5503 watch EXP: Set a watchpoint (breakpoint) for an expression.
5505 info watchpoints: Information about your watchpoints.
5507 delete N: Deletes watchpoint number N (same as breakpoints).
5508 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5509 enable N: Re-enables watchpoint number N (same as breakpoints).
5512 * C++ multiple inheritance
5514 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5517 * C++ exception handling
5519 Gdb now supports limited C++ exception handling. Besides the existing
5520 ability to breakpoint on an exception handler, gdb can breakpoint on
5521 the raising of an exception (before the stack is peeled back to the
5524 catch FOO: If there is a FOO exception handler in the dynamic scope,
5525 set a breakpoint to catch exceptions which may be raised there.
5526 Multiple exceptions (``catch foo bar baz'') may be caught.
5528 info catch: Lists all exceptions which may be caught in the
5529 current stack frame.
5532 * Minor command changes
5534 The command ``call func (arg, arg, ...)'' now acts like the print
5535 command, except it does not print or save a value if the function's result
5536 is void. This is similar to dbx usage.
5538 The ``up'' and ``down'' commands now always print the frame they end up
5539 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5540 frames without printing.
5542 * New directory command
5544 'dir' now adds directories to the FRONT of the source search path.
5545 The path starts off empty. Source files that contain debug information
5546 about the directory in which they were compiled can be found even
5547 with an empty path; Sun CC and GCC include this information. If GDB can't
5548 find your source file in the current directory, type "dir .".
5550 * Configuring GDB for compilation
5552 For normal use, type ``./configure host''. See README or gdb.texinfo
5555 GDB now handles cross debugging. If you are remotely debugging between
5556 two different machines, type ``./configure host -target=targ''.
5557 Host is the machine where GDB will run; targ is the machine
5558 where the program that you are debugging will run.