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.
87 set debug symfile off|on
89 Control display of debugging info regarding reading symbol files and
90 symbol tables within those files
92 set print raw frame-arguments
93 show print raw frame-arguments
94 Set/show whether to print frame arguments in raw mode,
95 disregarding any defined pretty-printers.
97 set remote trace-status-packet
98 show remote trace-status-packet
99 Set/show the use of remote protocol qTStatus packet.
103 Control display of debugging messages related to Nios II targets.
107 Control whether target-assisted range stepping is enabled.
109 set startup-with-shell
110 show startup-with-shell
111 Specifies whether Unix child processes are started via a shell or
114 * You can now use a literal value 'unlimited' for options that
115 interpret 0 or -1 as meaning "unlimited". E.g., "set
116 trace-buffer-size unlimited" is now an alias for "set
117 trace-buffer-size -1" and "set height unlimited" is now an alias for
120 * The "set debug symtab-create" debugging option of GDB has been changed to
121 accept a verbosity level. 0 means "off", 1 provides basic debugging
122 output, and values of 2 or greater provides more verbose output.
124 * New command-line options
126 Display the details of GDB configure-time options.
128 * The command 'tsave' can now support new option '-ctf' to save trace
129 buffer in Common Trace Format.
131 * Newly installed $prefix/bin/gcore acts as a shell interface for the
134 * GDB now implements the the C++ 'typeid' operator.
136 * The new convenience variable $_exception holds the exception being
137 thrown or caught at an exception-related catchpoint.
139 * The exception-related catchpoints, like "catch throw", now accept a
140 regular expression which can be used to filter exceptions by type.
142 * The new convenience variable $_exitsignal is automatically set to
143 the terminating signal number when the program being debugged dies
144 due to an uncaught signal.
148 ** The -trace-save MI command can optionally save trace buffer in Common
151 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
153 ** The command -data-list-register-values now accepts an optional
154 "--skip-unavailable" option. When used, only the available registers
157 ** The new command -trace-frame-collected dumps collected variables,
158 computed expressions, tvars, memory and registers in a traceframe.
160 ** The commands -stack-list-locals, -stack-list-arguments and
161 -stack-list-variables now accept an option "--skip-unavailable".
162 When used, only the available locals or arguments are displayed.
164 ** The -exec-run command now accepts an optional "--start" option.
165 When used, the command follows the same semantics as the "start"
166 command, stopping the program's execution at the start of its
169 ** The new commands -catch-assert and -catch-exceptions insert
170 catchpoints stopping the program when Ada exceptions are raised.
172 * New system-wide configuration scripts
173 A GDB installation now provides scripts suitable for use as system-wide
174 configuration scripts for the following systems:
178 * GDB now supports target-assigned range stepping with remote targets.
179 This improves the performance of stepping source lines by reducing
180 the number of control packets from/to GDB. See "New remote packets"
183 * GDB now understands the element 'tvar' in the XML traceframe info.
184 It has the id of the collected trace state variables.
186 * On S/390 targets that provide the transactional-execution feature,
187 the program interruption transaction diagnostic block (TDB) is now
188 represented as a number of additional "registers" in GDB.
194 The vCont packet supports a new 'r' action, that tells the remote
195 stub to step through an address range itself, without GDB
196 involvemement at each single-step.
198 qXfer:libraries-svr4:read's annex
199 The previously unused annex of the qXfer:libraries-svr4:read packet
200 is now used to support passing an argument list. The remote stub
201 reports support for this argument list to GDB's qSupported query.
202 The defined arguments are "start" and "prev", used to reduce work
203 necessary for library list updating, resulting in significant
206 * New features in the GDB remote stub, GDBserver
208 ** GDBserver now supports target-assisted range stepping. Currently
209 enabled on x86/x86_64 GNU/Linux targets.
211 ** GDBserver now adds element 'tvar' in the XML in the reply to
212 'qXfer:traceframe-info:read'. It has the id of the collected
213 trace state variables.
215 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
218 * New 'z' formatter for printing and examining memory, this displays the
219 value as hexadecimal zero padded on the left to the size of the type.
221 * GDB can now use Windows x64 unwinding data.
223 * The "set remotebaud" command has been replaced by "set serial baud".
224 Similarly, "show remotebaud" has been replaced by "show serial baud".
225 The "set remotebaud" and "show remotebaud" commands are still available
226 to provide backward compatibility with older versions of GDB.
228 *** Changes in GDB 7.6
230 * Target record has been renamed to record-full.
231 Record/replay is now enabled with the "record full" command.
232 This also affects settings that are associated with full record/replay
233 that have been moved from "set/show record" to "set/show record full":
235 set|show record full insn-number-max
236 set|show record full stop-at-limit
237 set|show record full memory-query
239 * A new record target "record-btrace" has been added. The new target
240 uses hardware support to record the control-flow of a process. It
241 does not support replaying the execution, but it implements the
242 below new commands for investigating the recorded execution log.
243 This new recording method can be enabled using:
247 The "record-btrace" target is only available on Intel Atom processors
248 and requires a Linux kernel 2.6.32 or later.
250 * Two new commands have been added for record/replay to give information
251 about the recorded execution without having to replay the execution.
252 The commands are only supported by "record btrace".
254 record instruction-history prints the execution history at
255 instruction granularity
257 record function-call-history prints the execution history at
260 * New native configurations
262 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
263 FreeBSD/powerpc powerpc*-*-freebsd
264 x86_64/Cygwin x86_64-*-cygwin*
265 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
269 ARM AArch64 aarch64*-*-elf
270 ARM AArch64 GNU/Linux aarch64*-*-linux
271 Lynx 178 PowerPC powerpc-*-lynx*178
272 x86_64/Cygwin x86_64-*-cygwin*
273 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
275 * If the configured location of system.gdbinit file (as given by the
276 --with-system-gdbinit option at configure time) is in the
277 data-directory (as specified by --with-gdb-datadir at configure
278 time) or in one of its subdirectories, then GDB will look for the
279 system-wide init file in the directory specified by the
280 --data-directory command-line option.
282 * New command line options:
284 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
285 other initialization files, unlike -nx which disables all of them.
287 * Removed command line options
289 -epoch This was used by the gdb mode in Epoch, an ancient fork of
292 * The 'ptype' and 'whatis' commands now accept an argument to control
295 * 'info proc' now works on some core files.
299 ** Vectors can be created with gdb.Type.vector.
301 ** Python's atexit.register now works in GDB.
303 ** Types can be pretty-printed via a Python API.
305 ** Python 3 is now supported (in addition to Python 2.4 or later)
307 ** New class gdb.Architecture exposes GDB's internal representation
308 of architecture in the Python API.
310 ** New method Frame.architecture returns the gdb.Architecture object
311 corresponding to the frame's architecture.
313 * New Python-based convenience functions:
315 ** $_memeq(buf1, buf2, length)
316 ** $_streq(str1, str2)
318 ** $_regex(str, regex)
320 * The 'cd' command now defaults to using '~' (the home directory) if not
323 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
324 default for GCC since November 2000.
326 * The command 'forward-search' can now be abbreviated as 'fo'.
328 * The command 'info tracepoints' can now display 'installed on target'
329 or 'not installed on target' for each non-pending location of tracepoint.
331 * New configure options
333 --enable-libmcheck/--disable-libmcheck
334 By default, development versions are built with -lmcheck on hosts
335 that support it, in order to help track memory corruption issues.
336 Release versions, on the other hand, are built without -lmcheck
337 by default. The --enable-libmcheck/--disable-libmcheck configure
338 options allow the user to override that default.
339 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
340 This configure option allows the user to build GDB with
341 libbabeltrace using which GDB can read Common Trace Format data.
343 * New commands (for set/show, see "New options" below)
346 Catch signals. This is similar to "handle", but allows commands and
347 conditions to be attached.
350 List the BFDs known to GDB.
352 python-interactive [command]
354 Start a Python interactive prompt, or evaluate the optional command
355 and print the result of expressions.
358 "py" is a new alias for "python".
360 enable type-printer [name]...
361 disable type-printer [name]...
362 Enable or disable type printers.
366 ** For the Renesas Super-H architecture, the "regs" command has been removed
367 (has been deprecated in GDB 7.5), and "info all-registers" should be used
372 set print type methods (on|off)
373 show print type methods
374 Control whether method declarations are displayed by "ptype".
375 The default is to show them.
377 set print type typedefs (on|off)
378 show print type typedefs
379 Control whether typedef definitions are displayed by "ptype".
380 The default is to show them.
382 set filename-display basename|relative|absolute
383 show filename-display
384 Control the way in which filenames is displayed.
385 The default is "relative", which preserves previous behavior.
387 set trace-buffer-size
388 show trace-buffer-size
389 Request target to change the size of trace buffer.
391 set remote trace-buffer-size-packet auto|on|off
392 show remote trace-buffer-size-packet
393 Control the use of the remote protocol `QTBuffer:size' packet.
397 Control display of debugging messages related to ARM AArch64.
400 set debug coff-pe-read
401 show debug coff-pe-read
402 Control display of debugging messages related to reading of COFF/PE
407 Control display of debugging messages related to Mach-O symbols
410 set debug notification
411 show debug notification
412 Control display of debugging info for async remote notification.
416 ** Command parameter changes are now notified using new async record
417 "=cmd-param-changed".
418 ** Trace frame changes caused by command "tfind" are now notified using
419 new async record "=traceframe-changed".
420 ** The creation, deletion and modification of trace state variables
421 are now notified using new async records "=tsv-created",
422 "=tsv-deleted" and "=tsv-modified".
423 ** The start and stop of process record are now notified using new
424 async record "=record-started" and "=record-stopped".
425 ** Memory changes are now notified using new async record
427 ** The data-disassemble command response will include a "fullname" field
428 containing the absolute file name when source has been requested.
429 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
430 command, to allow pattern filling of memory areas.
431 ** New commands "-catch-load"/"-catch-unload" added for intercepting
432 library load/unload events.
433 ** The response to breakpoint commands and breakpoint async records
434 includes an "installed" field containing a boolean state about each
435 non-pending tracepoint location is whether installed on target or not.
436 ** Output of the "-trace-status" command includes a "trace-file" field
437 containing the name of the trace file being examined. This field is
438 optional, and only present when examining a trace file.
439 ** The "fullname" field is now always present along with the "file" field,
440 even if the file cannot be found by GDB.
442 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
443 You must have the LZMA library available when configuring GDB for this
444 feature to be enabled. For more information, see:
445 http://fedoraproject.org/wiki/Features/MiniDebugInfo
450 Set the size of trace buffer. The remote stub reports support for this
451 packet to gdb's qSupported query.
454 Enable Branch Trace Store (BTS)-based branch tracing for the current
455 thread. The remote stub reports support for this packet to gdb's
459 Disable branch tracing for the current thread. The remote stub reports
460 support for this packet to gdb's qSupported query.
463 Read the traced branches for the current thread. The remote stub
464 reports support for this packet to gdb's qSupported query.
466 *** Changes in GDB 7.5
468 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
469 for more x32 ABI info.
471 * GDB now supports access to MIPS DSP registers on Linux targets.
473 * GDB now supports debugging microMIPS binaries.
475 * The "info os" command on GNU/Linux can now display information on
476 several new classes of objects managed by the operating system:
477 "info os procgroups" lists process groups
478 "info os files" lists file descriptors
479 "info os sockets" lists internet-domain sockets
480 "info os shm" lists shared-memory regions
481 "info os semaphores" lists semaphores
482 "info os msg" lists message queues
483 "info os modules" lists loaded kernel modules
485 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
486 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
487 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
488 options and inspect the probe arguments using the new $_probe_arg family
489 of convenience variables. You can obtain more information about SystemTap
490 in <http://sourceware.org/systemtap/>.
492 * GDB now supports reversible debugging on ARM, it allows you to
493 debug basic ARM and THUMB instructions, and provides
494 record/replay support.
496 * The option "symbol-reloading" has been deleted as it is no longer used.
500 ** GDB commands implemented in Python can now be put in command class
503 ** The "maint set python print-stack on|off" is now deleted.
505 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
506 apply "flag enum"-style pretty-printing to any enum.
508 ** gdb.lookup_symbol can now work when there is no current frame.
510 ** gdb.Symbol now has a 'line' attribute, holding the line number in
511 the source at which the symbol was defined.
513 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
514 method 'value'. The former indicates whether the symbol needs a
515 frame in order to compute its value, and the latter computes the
518 ** A new method 'referenced_value' on gdb.Value objects which can
519 dereference pointer as well as C++ reference values.
521 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
522 which return the global and static blocks (as gdb.Block objects),
523 of the underlying symbol table, respectively.
525 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
526 object associated with a PC value.
528 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
529 of the address range occupied by code for the current source line.
531 * Go language support.
532 GDB now supports debugging programs written in the Go programming
535 * GDBserver now supports stdio connections.
536 E.g. (gdb) target remote | ssh myhost gdbserver - hello
538 * The binary "gdbtui" can no longer be built or installed.
539 Use "gdb -tui" instead.
541 * GDB will now print "flag" enums specially. A flag enum is one where
542 all the enumerator values have no bits in common when pairwise
543 "and"ed. When printing a value whose type is a flag enum, GDB will
544 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
545 (gdb) print (enum E) 3
548 * The filename part of a linespec will now match trailing components
549 of a source file name. For example, "break gcc/expr.c:1000" will
550 now set a breakpoint in build/gcc/expr.c, but not
553 * The "info proc" and "generate-core-file" commands will now also
554 work on remote targets connected to GDBserver on Linux.
556 * The command "info catch" has been removed. It has been disabled
559 * The "catch exception" and "catch assert" commands now accept
560 a condition at the end of the command, much like the "break"
561 command does. For instance:
563 (gdb) catch exception Constraint_Error if Barrier = True
565 Previously, it was possible to add a condition to such catchpoints,
566 but it had to be done as a second step, after the catchpoint had been
567 created, using the "condition" command.
569 * The "info static-tracepoint-marker" command will now also work on
570 native Linux targets with in-process agent.
572 * GDB can now set breakpoints on inlined functions.
574 * The .gdb_index section has been updated to include symbols for
575 inlined functions. GDB will ignore older .gdb_index sections by
576 default, which could cause symbol files to be loaded more slowly
577 until their .gdb_index sections can be recreated. The new command
578 "set use-deprecated-index-sections on" will cause GDB to use any older
579 .gdb_index sections it finds. This will restore performance, but the
580 ability to set breakpoints on inlined functions will be lost in symbol
581 files with older .gdb_index sections.
583 The .gdb_index section has also been updated to record more information
584 about each symbol. This speeds up the "info variables", "info functions"
585 and "info types" commands when used with programs having the .gdb_index
586 section, as well as speeding up debugging with shared libraries using
587 the .gdb_index section.
589 * Ada support for GDB/MI Variable Objects has been added.
591 * GDB can now support 'breakpoint always-inserted mode' in 'record'
596 ** New command -info-os is the MI equivalent of "info os".
598 ** Output logs ("set logging" and related) now include MI output.
602 ** "set use-deprecated-index-sections on|off"
603 "show use-deprecated-index-sections on|off"
604 Controls the use of deprecated .gdb_index sections.
606 ** "catch load" and "catch unload" can be used to stop when a shared
607 library is loaded or unloaded, respectively.
609 ** "enable count" can be used to auto-disable a breakpoint after
612 ** "info vtbl" can be used to show the virtual method tables for
613 C++ and Java objects.
615 ** "explore" and its sub commands "explore value" and "explore type"
616 can be used to reccursively explore values and types of
617 expressions. These commands are available only if GDB is
618 configured with '--with-python'.
620 ** "info auto-load" shows status of all kinds of auto-loaded files,
621 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
622 sequences of commands files, "info auto-load python-scripts"
623 shows status of auto-loading Python script files,
624 "info auto-load local-gdbinit" shows status of loading init file
625 (.gdbinit) from current directory and "info auto-load libthread-db" shows
626 status of inferior specific thread debugging shared library loading.
628 ** "info auto-load-scripts", "set auto-load-scripts on|off"
629 and "show auto-load-scripts" commands have been deprecated, use their
630 "info auto-load python-scripts", "set auto-load python-scripts on|off"
631 and "show auto-load python-scripts" counterparts instead.
633 ** "dprintf location,format,args..." creates a dynamic printf, which
634 is basically a breakpoint that does a printf and immediately
635 resumes your program's execution, so it is like a printf that you
636 can insert dynamically at runtime instead of at compiletime.
638 ** "set print symbol"
640 Controls whether GDB attempts to display the symbol, if any,
641 corresponding to addresses it prints. This defaults to "on", but
642 you can set it to "off" to restore GDB's previous behavior.
644 * Deprecated commands
646 ** For the Renesas Super-H architecture, the "regs" command has been
647 deprecated, and "info all-registers" should be used instead.
651 Renesas RL78 rl78-*-elf
652 HP OpenVMS ia64 ia64-hp-openvms*
654 * GDBserver supports evaluation of breakpoint conditions. When
655 support is advertised by GDBserver, GDB may be told to send the
656 breakpoint conditions in bytecode form to GDBserver. GDBserver
657 will only report the breakpoint trigger to GDB when its condition
663 show mips compression
664 Select the compressed ISA encoding used in functions that have no symbol
665 information available. The encoding can be set to either of:
668 and is updated automatically from ELF file flags if available.
670 set breakpoint condition-evaluation
671 show breakpoint condition-evaluation
672 Control whether breakpoint conditions are evaluated by GDB ("host") or by
673 GDBserver ("target"). Default option "auto" chooses the most efficient
675 This option can improve debugger efficiency depending on the speed of the
679 Disable auto-loading globally.
682 Show auto-loading setting of all kinds of auto-loaded files.
684 set auto-load gdb-scripts on|off
685 show auto-load gdb-scripts
686 Control auto-loading of GDB canned sequences of commands files.
688 set auto-load python-scripts on|off
689 show auto-load python-scripts
690 Control auto-loading of Python script files.
692 set auto-load local-gdbinit on|off
693 show auto-load local-gdbinit
694 Control loading of init file (.gdbinit) from current directory.
696 set auto-load libthread-db on|off
697 show auto-load libthread-db
698 Control auto-loading of inferior specific thread debugging shared library.
700 set auto-load scripts-directory <dir1>[:<dir2>...]
701 show auto-load scripts-directory
702 Set a list of directories from which to load auto-loaded scripts.
703 Automatically loaded Python scripts and GDB scripts are located in one
704 of the directories listed by this option.
705 The delimiter (':' above) may differ according to the host platform.
707 set auto-load safe-path <dir1>[:<dir2>...]
708 show auto-load safe-path
709 Set a list of directories from which it is safe to auto-load files.
710 The delimiter (':' above) may differ according to the host platform.
712 set debug auto-load on|off
714 Control display of debugging info for auto-loading the files above.
716 set dprintf-style gdb|call|agent
718 Control the way in which a dynamic printf is performed; "gdb"
719 requests a GDB printf command, while "call" causes dprintf to call a
720 function in the inferior. "agent" requests that the target agent
721 (such as GDBserver) do the printing.
723 set dprintf-function <expr>
724 show dprintf-function
725 set dprintf-channel <expr>
727 Set the function and optional first argument to the call when using
728 the "call" style of dynamic printf.
730 set disconnected-dprintf on|off
731 show disconnected-dprintf
732 Control whether agent-style dynamic printfs continue to be in effect
733 after GDB disconnects.
735 * New configure options
738 Configure default value for the 'set auto-load scripts-directory'
739 setting above. It defaults to '$debugdir:$datadir/auto-load',
740 $debugdir representing global debugging info directories (available
741 via 'show debug-file-directory') and $datadir representing GDB's data
742 directory (available via 'show data-directory').
744 --with-auto-load-safe-path
745 Configure default value for the 'set auto-load safe-path' setting
746 above. It defaults to the --with-auto-load-dir setting.
748 --without-auto-load-safe-path
749 Set 'set auto-load safe-path' to '/', effectively disabling this
754 z0/z1 conditional breakpoints extension
756 The z0/z1 breakpoint insertion packets have been extended to carry
757 a list of conditional expressions over to the remote stub depending on the
758 condition evaluation mode. The use of this extension can be controlled
759 via the "set remote conditional-breakpoints-packet" command.
763 Specify the signals which the remote stub may pass to the debugged
764 program without GDB involvement.
766 * New command line options
768 --init-command=FILE, -ix Like --command, -x but execute it
769 before loading inferior.
770 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
771 execute it before loading inferior.
773 *** Changes in GDB 7.4
775 * GDB now handles ambiguous linespecs more consistently; the existing
776 FILE:LINE support has been expanded to other types of linespecs. A
777 breakpoint will now be set on all matching locations in all
778 inferiors, and locations will be added or removed according to
781 * GDB now allows you to skip uninteresting functions and files when
782 stepping with the "skip function" and "skip file" commands.
784 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
785 and "show remote hardware-watchpoint-length-limit". These allows to
786 set or show the maximum length limit (in bytes) of a remote
787 target hardware watchpoint.
789 This allows e.g. to use "unlimited" hardware watchpoints with the
790 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
791 watchpoints are slower than real hardware watchpoints but are
792 significantly faster than gdb software watchpoints.
796 ** The register_pretty_printer function in module gdb.printing now takes
797 an optional `replace' argument. If True, the new printer replaces any
800 ** The "maint set python print-stack on|off" command has been
801 deprecated and will be deleted in GDB 7.5.
802 A new command: "set python print-stack none|full|message" has
803 replaced it. Additionally, the default for "print-stack" is
804 now "message", which just prints the error message without
807 ** A prompt substitution hook (prompt_hook) is now available to the
810 ** A new Python module, gdb.prompt has been added to the GDB Python
811 modules library. This module provides functionality for
812 escape sequences in prompts (used by set/show
813 extended-prompt). These escape sequences are replaced by their
816 ** Python commands and convenience-functions located in
817 'data-directory'/python/gdb/command and
818 'data-directory'/python/gdb/function are now automatically loaded
821 ** Blocks now provide four new attributes. global_block and
822 static_block will return the global and static blocks
823 respectively. is_static and is_global are boolean attributes
824 that indicate if the block is one of those two types.
826 ** Symbols now provide the "type" attribute, the type of the symbol.
828 ** The "gdb.breakpoint" function has been deprecated in favor of
831 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
832 of a function. This class is based on the "finish" command
833 available in the CLI.
835 ** Type objects for struct and union types now allow access to
836 the fields using standard Python dictionary (mapping) methods.
837 For example, "some_type['myfield']" now works, as does
840 ** A new event "gdb.new_objfile" has been added, triggered by loading a
843 ** A new function, "deep_items" has been added to the gdb.types
844 module in the GDB Python modules library. This function returns
845 an iterator over the fields of a struct or union type. Unlike
846 the standard Python "iteritems" method, it will recursively traverse
847 any anonymous fields.
851 ** "*stopped" events can report several new "reason"s, such as
854 ** Breakpoint changes are now notified using new async records, like
855 "=breakpoint-modified".
857 ** New command -ada-task-info.
859 * libthread-db-search-path now supports two special values: $sdir and $pdir.
860 $sdir specifies the default system locations of shared libraries.
861 $pdir specifies the directory where the libpthread used by the application
864 GDB no longer looks in $sdir and $pdir after it has searched the directories
865 mentioned in libthread-db-search-path. If you want to search those
866 directories, they must be specified in libthread-db-search-path.
867 The default value of libthread-db-search-path on GNU/Linux and Solaris
868 systems is now "$sdir:$pdir".
870 $pdir is not supported by gdbserver, it is currently ignored.
871 $sdir is supported by gdbserver.
873 * New configure option --with-iconv-bin.
874 When using the internationalization support like the one in the GNU C
875 library, GDB will invoke the "iconv" program to get a list of supported
876 character sets. If this program lives in a non-standard location, one can
877 use this option to specify where to find it.
879 * When natively debugging programs on PowerPC BookE processors running
880 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
881 watchpoints, which specify a mask in addition to an address to watch.
882 The mask specifies that some bits of an address (the bits which are
883 reset in the mask) should be ignored when matching the address accessed
884 by the inferior against the watchpoint address. See the "PowerPC Embedded"
885 section in the user manual for more details.
887 * The new option --once causes GDBserver to stop listening for connections once
888 the first connection is made. The listening port used by GDBserver will
889 become available after that.
891 * New commands "info macros" and "alias" have been added.
893 * New function parameters suffix @entry specifies value of function parameter
894 at the time the function got called. Entry values are available only since
900 "!" is now an alias of the "shell" command.
901 Note that no space is needed between "!" and SHELL COMMAND.
905 watch EXPRESSION mask MASK_VALUE
906 The watch command now supports the mask argument which allows creation
907 of masked watchpoints, if the current architecture supports this feature.
909 info auto-load-scripts [REGEXP]
910 This command was formerly named "maintenance print section-scripts".
911 It is now generally useful and is no longer a maintenance-only command.
913 info macro [-all] [--] MACRO
914 The info macro command has new options `-all' and `--'. The first for
915 printing all definitions of a macro. The second for explicitly specifying
916 the end of arguments and the beginning of the macro name in case the macro
917 name starts with a hyphen.
919 collect[/s] EXPRESSIONS
920 The tracepoint collect command now takes an optional modifier "/s"
921 that directs it to dereference pointer-to-character types and
922 collect the bytes of memory up to a zero byte. The behavior is
923 similar to what you see when you use the regular print command on a
924 string. An optional integer following the "/s" sets a bound on the
925 number of bytes that will be collected.
928 The trace start command now interprets any supplied arguments as a
929 note to be recorded with the trace run, with an effect similar to
930 setting the variable trace-notes.
933 The trace stop command now interprets any arguments as a note to be
934 mentioned along with the tstatus report that the trace was stopped
935 with a command. The effect is similar to setting the variable
938 * Tracepoints can now be enabled and disabled at any time after a trace
939 experiment has been started using the standard "enable" and "disable"
940 commands. It is now possible to start a trace experiment with no enabled
941 tracepoints; GDB will display a warning, but will allow the experiment to
942 begin, assuming that tracepoints will be enabled as needed while the trace
945 * Fast tracepoints on 32-bit x86-architectures can now be placed at
946 locations with 4-byte instructions, when they were previously
947 limited to locations with instructions of 5 bytes or longer.
951 set debug dwarf2-read
952 show debug dwarf2-read
953 Turns on or off display of debugging messages related to reading
954 DWARF debug info. The default is off.
956 set debug symtab-create
957 show debug symtab-create
958 Turns on or off display of debugging messages related to symbol table
959 creation. The default is off.
963 Set the GDB prompt, and allow escape sequences to be inserted to
964 display miscellaneous information (see 'help set extended-prompt'
965 for the list of sequences). This prompt (and any information
966 accessed through the escape sequences) is updated every time the
969 set print entry-values (both|compact|default|if-needed|no|only|preferred)
970 show print entry-values
971 Set printing of frame argument values at function entry. In some cases
972 GDB can determine the value of function argument which was passed by the
973 function caller, even if the value was modified inside the called function.
975 set debug entry-values
976 show debug entry-values
977 Control display of debugging info for determining frame argument values at
978 function entry and virtual tail call frames.
980 set basenames-may-differ
981 show basenames-may-differ
982 Set whether a source file may have multiple base names.
983 (A "base name" is the name of a file with the directory part removed.
984 Example: The base name of "/home/user/hello.c" is "hello.c".)
985 If set, GDB will canonicalize file names (e.g., expand symlinks)
986 before comparing them. Canonicalization is an expensive operation,
987 but it allows the same file be known by more than one base name.
988 If not set (the default), all source files are assumed to have just
989 one base name, and gdb will do file name comparisons more efficiently.
995 Set a user name and notes for the current and any future trace runs.
996 This is useful for long-running and/or disconnected traces, to
997 inform others (or yourself) as to who is running the trace, supply
998 contact information, or otherwise explain what is going on.
1000 set trace-stop-notes
1001 show trace-stop-notes
1002 Set a note attached to the trace run, that is displayed when the
1003 trace has been stopped by a tstop command. This is useful for
1004 instance as an explanation, if you are stopping a trace run that was
1005 started by someone else.
1007 * New remote packets
1011 Dynamically enable a tracepoint in a started trace experiment.
1015 Dynamically disable a tracepoint in a started trace experiment.
1019 Set the user and notes of the trace run.
1023 Query the current status of a tracepoint.
1027 Query the minimum length of instruction at which a fast tracepoint may
1030 * Dcache size (number of lines) and line-size are now runtime-configurable
1031 via "set dcache line" and "set dcache line-size" commands.
1035 Texas Instruments TMS320C6x tic6x-*-*
1039 Renesas RL78 rl78-*-elf
1041 *** Changes in GDB 7.3.1
1043 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1045 *** Changes in GDB 7.3
1047 * GDB has a new command: "thread find [REGEXP]".
1048 It finds the thread id whose name, target id, or thread extra info
1049 matches the given regular expression.
1051 * The "catch syscall" command now works on mips*-linux* targets.
1053 * The -data-disassemble MI command now supports modes 2 and 3 for
1054 dumping the instruction opcodes.
1056 * New command line options
1058 -data-directory DIR Specify DIR as the "data-directory".
1059 This is mostly for testing purposes.
1061 * The "maint set python auto-load on|off" command has been renamed to
1062 "set auto-load-scripts on|off".
1064 * GDB has a new command: "set directories".
1065 It is like the "dir" command except that it replaces the
1066 source path list instead of augmenting it.
1068 * GDB now understands thread names.
1070 On GNU/Linux, "info threads" will display the thread name as set by
1071 prctl or pthread_setname_np.
1073 There is also a new command, "thread name", which can be used to
1074 assign a name internally for GDB to display.
1077 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1078 has been integrated into GDB.
1082 ** The function gdb.Write now accepts an optional keyword 'stream'.
1083 This keyword, when provided, will direct the output to either
1084 stdout, stderr, or GDB's logging output.
1086 ** Parameters can now be be sub-classed in Python, and in particular
1087 you may implement the get_set_doc and get_show_doc functions.
1088 This improves how Parameter set/show documentation is processed
1089 and allows for more dynamic content.
1091 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1092 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1093 have an is_valid method.
1095 ** Breakpoints can now be sub-classed in Python, and in particular
1096 you may implement a 'stop' function that is executed each time
1097 the inferior reaches that breakpoint.
1099 ** New function gdb.lookup_global_symbol looks up a global symbol.
1101 ** GDB values in Python are now callable if the value represents a
1102 function. For example, if 'some_value' represents a function that
1103 takes two integer parameters and returns a value, you can call
1104 that function like so:
1106 result = some_value (10,20)
1108 ** Module gdb.types has been added.
1109 It contains a collection of utilities for working with gdb.Types objects:
1110 get_basic_type, has_field, make_enum_dict.
1112 ** Module gdb.printing has been added.
1113 It contains utilities for writing and registering pretty-printers.
1114 New classes: PrettyPrinter, SubPrettyPrinter,
1115 RegexpCollectionPrettyPrinter.
1116 New function: register_pretty_printer.
1118 ** New commands "info pretty-printers", "enable pretty-printer" and
1119 "disable pretty-printer" have been added.
1121 ** gdb.parameter("directories") is now available.
1123 ** New function gdb.newest_frame returns the newest frame in the
1126 ** The gdb.InferiorThread class has a new "name" attribute. This
1127 holds the thread's name.
1129 ** Python Support for Inferior events.
1130 Python scripts can add observers to be notified of events
1131 occurring in the process being debugged.
1132 The following events are currently supported:
1133 - gdb.events.cont Continue event.
1134 - gdb.events.exited Inferior exited event.
1135 - gdb.events.stop Signal received, and Breakpoint hit events.
1139 ** GDB now puts template parameters in scope when debugging in an
1140 instantiation. For example, if you have:
1142 template<int X> int func (void) { return X; }
1144 then if you step into func<5>, "print X" will show "5". This
1145 feature requires proper debuginfo support from the compiler; it
1146 was added to GCC 4.5.
1148 ** The motion commands "next", "finish", "until", and "advance" now
1149 work better when exceptions are thrown. In particular, GDB will
1150 no longer lose control of the inferior; instead, the GDB will
1151 stop the inferior at the point at which the exception is caught.
1152 This functionality requires a change in the exception handling
1153 code that was introduced in GCC 4.5.
1155 * GDB now follows GCC's rules on accessing volatile objects when
1156 reading or writing target state during expression evaluation.
1157 One notable difference to prior behavior is that "print x = 0"
1158 no longer generates a read of x; the value of the assignment is
1159 now always taken directly from the value being assigned.
1161 * GDB now has some support for using labels in the program's source in
1162 linespecs. For instance, you can use "advance label" to continue
1163 execution to a label.
1165 * GDB now has support for reading and writing a new .gdb_index
1166 section. This section holds a fast index of DWARF debugging
1167 information and can be used to greatly speed up GDB startup and
1168 operation. See the documentation for `save gdb-index' for details.
1170 * The "watch" command now accepts an optional "-location" argument.
1171 When used, this causes GDB to watch the memory referred to by the
1172 expression. Such a watchpoint is never deleted due to it going out
1175 * GDB now supports thread debugging of core dumps on GNU/Linux.
1177 GDB now activates thread debugging using the libthread_db library
1178 when debugging GNU/Linux core dumps, similarly to when debugging
1179 live processes. As a result, when debugging a core dump file, GDB
1180 is now able to display pthread_t ids of threads. For example, "info
1181 threads" shows the same output as when debugging the process when it
1182 was live. In earlier releases, you'd see something like this:
1185 * 1 LWP 6780 main () at main.c:10
1187 While now you see this:
1190 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1192 It is also now possible to inspect TLS variables when debugging core
1195 When debugging a core dump generated on a machine other than the one
1196 used to run GDB, you may need to point GDB at the correct
1197 libthread_db library with the "set libthread-db-search-path"
1198 command. See the user manual for more details on this command.
1200 * When natively debugging programs on PowerPC BookE processors running
1201 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1202 which stop execution of the inferior whenever it executes an instruction
1203 at any address within the specified range. See the "PowerPC Embedded"
1204 section in the user manual for more details.
1206 * New features in the GDB remote stub, GDBserver
1208 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1209 and i686 LynxOS (version 5.x).
1211 ** GDBserver is now supported on Blackfin Linux.
1213 * New native configurations
1215 ia64 HP-UX ia64-*-hpux*
1219 Analog Devices, Inc. Blackfin Processor bfin-*
1221 * Ada task switching is now supported on sparc-elf targets when
1222 debugging a program using the Ravenscar Profile. For more information,
1223 see the "Tasking Support when using the Ravenscar Profile" section
1224 in the GDB user manual.
1226 * Guile support was removed.
1228 * New features in the GNU simulator
1230 ** The --map-info flag lists all known core mappings.
1232 ** CFI flashes may be simulated via the "cfi" device.
1234 *** Changes in GDB 7.2
1236 * Shared library support for remote targets by default
1238 When GDB is configured for a generic, non-OS specific target, like
1239 for example, --target=arm-eabi or one of the many *-*-elf targets,
1240 GDB now queries remote stubs for loaded shared libraries using the
1241 `qXfer:libraries:read' packet. Previously, shared library support
1242 was always disabled for such configurations.
1246 ** Argument Dependent Lookup (ADL)
1248 In C++ ADL lookup directs function search to the namespaces of its
1249 arguments even if the namespace has not been imported.
1259 Here the compiler will search for `foo' in the namespace of 'b'
1260 and find A::foo. GDB now supports this. This construct is commonly
1261 used in the Standard Template Library for operators.
1263 ** Improved User Defined Operator Support
1265 In addition to member operators, GDB now supports lookup of operators
1266 defined in a namespace and imported with a `using' directive, operators
1267 defined in the global scope, operators imported implicitly from an
1268 anonymous namespace, and the ADL operators mentioned in the previous
1270 GDB now also supports proper overload resolution for all the previously
1271 mentioned flavors of operators.
1273 ** static const class members
1275 Printing of static const class members that are initialized in the
1276 class definition has been fixed.
1278 * Windows Thread Information Block access.
1280 On Windows targets, GDB now supports displaying the Windows Thread
1281 Information Block (TIB) structure. This structure is visible either
1282 by using the new command `info w32 thread-information-block' or, by
1283 dereferencing the new convenience variable named `$_tlb', a
1284 thread-specific pointer to the TIB. This feature is also supported
1285 when remote debugging using GDBserver.
1287 * Static tracepoints
1289 Static tracepoints are calls in the user program into a tracing
1290 library. One such library is a port of the LTTng kernel tracer to
1291 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1292 When debugging with GDBserver, GDB now supports combining the GDB
1293 tracepoint machinery with such libraries. For example: the user can
1294 use GDB to probe a static tracepoint marker (a call from the user
1295 program into the tracing library) with the new "strace" command (see
1296 "New commands" below). This creates a "static tracepoint" in the
1297 breakpoint list, that can be manipulated with the same feature set
1298 as fast and regular tracepoints. E.g., collect registers, local and
1299 global variables, collect trace state variables, and define
1300 tracepoint conditions. In addition, the user can collect extra
1301 static tracepoint marker specific data, by collecting the new
1302 $_sdata internal variable. When analyzing the trace buffer, you can
1303 inspect $_sdata like any other variable available to GDB. For more
1304 information, see the "Tracepoints" chapter in GDB user manual. New
1305 remote packets have been defined to support static tracepoints, see
1306 the "New remote packets" section below.
1308 * Better reconstruction of tracepoints after disconnected tracing
1310 GDB will attempt to download the original source form of tracepoint
1311 definitions when starting a trace run, and then will upload these
1312 upon reconnection to the target, resulting in a more accurate
1313 reconstruction of the tracepoints that are in use on the target.
1317 You can now exercise direct control over the ways that GDB can
1318 affect your program. For instance, you can disallow the setting of
1319 breakpoints, so that the program can run continuously (assuming
1320 non-stop mode). In addition, the "observer" variable is available
1321 to switch all of the different controls; in observer mode, GDB
1322 cannot affect the target's behavior at all, which is useful for
1323 tasks like diagnosing live systems in the field.
1325 * The new convenience variable $_thread holds the number of the
1328 * New remote packets
1332 Return the address of the Windows Thread Information Block of a given thread.
1336 In response to several of the tracepoint packets, the target may now
1337 also respond with a number of intermediate `qRelocInsn' request
1338 packets before the final result packet, to have GDB handle
1339 relocating an instruction to execute at a different address. This
1340 is particularly useful for stubs that support fast tracepoints. GDB
1341 reports support for this feature in the qSupported packet.
1345 List static tracepoint markers in the target program.
1349 List static tracepoint markers at a given address in the target
1352 qXfer:statictrace:read
1354 Read the static trace data collected (by a `collect $_sdata'
1355 tracepoint action). The remote stub reports support for this packet
1356 to gdb's qSupported query.
1360 Send the current settings of GDB's permission flags.
1364 Send part of the source (textual) form of a tracepoint definition,
1365 which includes location, conditional, and action list.
1367 * The source command now accepts a -s option to force searching for the
1368 script in the source search path even if the script name specifies
1371 * New features in the GDB remote stub, GDBserver
1373 - GDBserver now support tracepoints (including fast tracepoints, and
1374 static tracepoints). The feature is currently supported by the
1375 i386-linux and amd64-linux builds. See the "Tracepoints support
1376 in gdbserver" section in the manual for more information.
1378 GDBserver JIT compiles the tracepoint's conditional agent
1379 expression bytecode into native code whenever possible for low
1380 overhead dynamic tracepoints conditionals. For such tracepoints,
1381 an expression that examines program state is evaluated when the
1382 tracepoint is reached, in order to determine whether to capture
1383 trace data. If the condition is simple and false, processing the
1384 tracepoint finishes very quickly and no data is gathered.
1386 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1387 for static tracepoints support.
1389 - GDBserver now supports x86_64 Windows 64-bit debugging.
1391 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1392 it understands register description.
1394 * The --batch flag now disables pagination and queries.
1396 * X86 general purpose registers
1398 GDB now supports reading/writing byte, word and double-word x86
1399 general purpose registers directly. This means you can use, say,
1400 $ah or $ax to refer, respectively, to the byte register AH and
1401 16-bit word register AX that are actually portions of the 32-bit
1402 register EAX or 64-bit register RAX.
1404 * The `commands' command now accepts a range of breakpoints to modify.
1405 A plain `commands' following a command that creates multiple
1406 breakpoints affects all the breakpoints set by that command. This
1407 applies to breakpoints set by `rbreak', and also applies when a
1408 single `break' command creates multiple breakpoints (e.g.,
1409 breakpoints on overloaded c++ functions).
1411 * The `rbreak' command now accepts a filename specification as part of
1412 its argument, limiting the functions selected by the regex to those
1413 in the specified file.
1415 * Support for remote debugging Windows and SymbianOS shared libraries
1416 from Unix hosts has been improved. Non Windows GDB builds now can
1417 understand target reported file names that follow MS-DOS based file
1418 system semantics, such as file names that include drive letters and
1419 use the backslash character as directory separator. This makes it
1420 possible to transparently use the "set sysroot" and "set
1421 solib-search-path" on Unix hosts to point as host copies of the
1422 target's shared libraries. See the new command "set
1423 target-file-system-kind" described below, and the "Commands to
1424 specify files" section in the user manual for more information.
1428 eval template, expressions...
1429 Convert the values of one or more expressions under the control
1430 of the string template to a command line, and call it.
1432 set target-file-system-kind unix|dos-based|auto
1433 show target-file-system-kind
1434 Set or show the assumed file system kind for target reported file
1437 save breakpoints <filename>
1438 Save all current breakpoint definitions to a file suitable for use
1439 in a later debugging session. To read the saved breakpoint
1440 definitions, use the `source' command.
1442 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1445 info static-tracepoint-markers
1446 Display information about static tracepoint markers in the target.
1448 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1449 Define a static tracepoint by probing a marker at the given
1450 function, line, address, or marker ID.
1454 Enable and disable observer mode.
1456 set may-write-registers on|off
1457 set may-write-memory on|off
1458 set may-insert-breakpoints on|off
1459 set may-insert-tracepoints on|off
1460 set may-insert-fast-tracepoints on|off
1461 set may-interrupt on|off
1462 Set individual permissions for GDB effects on the target. Note that
1463 some of these settings can have undesirable or surprising
1464 consequences, particularly when changed in the middle of a session.
1465 For instance, disabling the writing of memory can prevent
1466 breakpoints from being inserted, cause single-stepping to fail, or
1467 even crash your program, if you disable after breakpoints have been
1468 inserted. However, GDB should not crash.
1470 set record memory-query on|off
1471 show record memory-query
1472 Control whether to stop the inferior if memory changes caused
1473 by an instruction cannot be recorded.
1478 The disassemble command now supports "start,+length" form of two arguments.
1482 ** GDB now provides a new directory location, called the python directory,
1483 where Python scripts written for GDB can be installed. The location
1484 of that directory is <data-directory>/python, where <data-directory>
1485 is the GDB data directory. For more details, see section `Scripting
1486 GDB using Python' in the manual.
1488 ** The GDB Python API now has access to breakpoints, symbols, symbol
1489 tables, program spaces, inferiors, threads and frame's code blocks.
1490 Additionally, GDB Parameters can now be created from the API, and
1491 manipulated via set/show in the CLI.
1493 ** New functions gdb.target_charset, gdb.target_wide_charset,
1494 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1496 ** New exception gdb.GdbError.
1498 ** Pretty-printers are now also looked up in the current program space.
1500 ** Pretty-printers can now be individually enabled and disabled.
1502 ** GDB now looks for names of Python scripts to auto-load in a
1503 special section named `.debug_gdb_scripts', in addition to looking
1504 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1506 * Tracepoint actions were unified with breakpoint commands. In particular,
1507 there are no longer differences in "info break" output for breakpoints and
1508 tracepoints and the "commands" command can be used for both tracepoints and
1509 regular breakpoints.
1513 ARM Symbian arm*-*-symbianelf*
1515 * D language support.
1516 GDB now supports debugging programs written in the D programming
1519 * GDB now supports the extended ptrace interface for PowerPC which is
1520 available since Linux kernel version 2.6.34. This automatically enables
1521 any hardware breakpoints and additional hardware watchpoints available in
1522 the processor. The old ptrace interface exposes just one hardware
1523 watchpoint and no hardware breakpoints.
1525 * GDB is now able to use the Data Value Compare (DVC) register available on
1526 embedded PowerPC processors to implement in hardware simple watchpoint
1527 conditions of the form:
1529 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1531 This works in native GDB running on Linux kernels with the extended ptrace
1532 interface mentioned above.
1534 *** Changes in GDB 7.1
1538 ** Namespace Support
1540 GDB now supports importing of namespaces in C++. This enables the
1541 user to inspect variables from imported namespaces. Support for
1542 namepace aliasing has also been added. So, if a namespace is
1543 aliased in the current scope (e.g. namepace C=A; ) the user can
1544 print variables using the alias (e.g. (gdb) print C::x).
1548 All known bugs relating to the printing of virtual base class were
1549 fixed. It is now possible to call overloaded static methods using a
1554 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1555 and reinterpret_cast<> are now handled by the C++ expression parser.
1559 Xilinx MicroBlaze microblaze-*-*
1564 Xilinx MicroBlaze microblaze
1567 * Multi-program debugging.
1569 GDB now has support for multi-program (a.k.a. multi-executable or
1570 multi-exec) debugging. This allows for debugging multiple inferiors
1571 simultaneously each running a different program under the same GDB
1572 session. See "Debugging Multiple Inferiors and Programs" in the
1573 manual for more information. This implied some user visible changes
1574 in the multi-inferior support. For example, "info inferiors" now
1575 lists inferiors that are not running yet or that have exited
1576 already. See also "New commands" and "New options" below.
1578 * New tracing features
1580 GDB's tracepoint facility now includes several new features:
1582 ** Trace state variables
1584 GDB tracepoints now include support for trace state variables, which
1585 are variables managed by the target agent during a tracing
1586 experiment. They are useful for tracepoints that trigger each
1587 other, so for instance one tracepoint can count hits in a variable,
1588 and then a second tracepoint has a condition that is true when the
1589 count reaches a particular value. Trace state variables share the
1590 $-syntax of GDB convenience variables, and can appear in both
1591 tracepoint actions and condition expressions. Use the "tvariable"
1592 command to create, and "info tvariables" to view; see "Trace State
1593 Variables" in the manual for more detail.
1597 GDB now includes an option for defining fast tracepoints, which
1598 targets may implement more efficiently, such as by installing a jump
1599 into the target agent rather than a trap instruction. The resulting
1600 speedup can be by two orders of magnitude or more, although the
1601 tradeoff is that some program locations on some target architectures
1602 might not allow fast tracepoint installation, for instance if the
1603 instruction to be replaced is shorter than the jump. To request a
1604 fast tracepoint, use the "ftrace" command, with syntax identical to
1605 the regular trace command.
1607 ** Disconnected tracing
1609 It is now possible to detach GDB from the target while it is running
1610 a trace experiment, then reconnect later to see how the experiment
1611 is going. In addition, a new variable disconnected-tracing lets you
1612 tell the target agent whether to continue running a trace if the
1613 connection is lost unexpectedly.
1617 GDB now has the ability to save the trace buffer into a file, and
1618 then use that file as a target, similarly to you can do with
1619 corefiles. You can select trace frames, print data that was
1620 collected in them, and use tstatus to display the state of the
1621 tracing run at the moment that it was saved. To create a trace
1622 file, use "tsave <filename>", and to use it, do "target tfile
1625 ** Circular trace buffer
1627 You can ask the target agent to handle the trace buffer as a
1628 circular buffer, discarding the oldest trace frames to make room for
1629 newer ones, by setting circular-trace-buffer to on. This feature may
1630 not be available for all target agents.
1635 The disassemble command, when invoked with two arguments, now requires
1636 the arguments to be comma-separated.
1639 The info variables command now displays variable definitions. Files
1640 which only declare a variable are not shown.
1643 The source command is now capable of sourcing Python scripts.
1644 This feature is dependent on the debugger being build with Python
1647 Related to this enhancement is also the introduction of a new command
1648 "set script-extension" (see below).
1650 * New commands (for set/show, see "New options" below)
1652 record save [<FILENAME>]
1653 Save a file (in core file format) containing the process record
1654 execution log for replay debugging at a later time.
1656 record restore <FILENAME>
1657 Restore the process record execution log that was saved at an
1658 earlier time, for replay debugging.
1660 add-inferior [-copies <N>] [-exec <FILENAME>]
1663 clone-inferior [-copies <N>] [ID]
1664 Make a new inferior ready to execute the same program another
1665 inferior has loaded.
1670 maint info program-spaces
1671 List the program spaces loaded into GDB.
1673 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1674 show remote interrupt-sequence
1675 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1676 as the sequence to the remote target in order to interrupt the execution.
1677 Ctrl-C is a default. Some system prefers BREAK which is high level of
1678 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1679 Magic SysRq g. It is BREAK signal and character 'g'.
1681 set remote interrupt-on-connect [on | off]
1682 show remote interrupt-on-connect
1683 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1684 remote target when gdb connects to it. This is needed when you debug
1687 set remotebreak [on | off]
1689 Deprecated. Use "set/show remote interrupt-sequence" instead.
1691 tvariable $NAME [ = EXP ]
1692 Create or modify a trace state variable.
1695 List trace state variables and their values.
1697 delete tvariable $NAME ...
1698 Delete one or more trace state variables.
1701 Evaluate the given expressions without collecting anything into the
1702 trace buffer. (Valid in tracepoint actions only.)
1704 ftrace FN / FILE:LINE / *ADDR
1705 Define a fast tracepoint at the given function, line, or address.
1707 * New expression syntax
1709 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1710 GDB now parses 0b101010 identically with 42.
1714 set follow-exec-mode new|same
1715 show follow-exec-mode
1716 Control whether GDB reuses the same inferior across an exec call or
1717 creates a new one. This is useful to be able to restart the old
1718 executable after the inferior having done an exec call.
1720 set default-collect EXPR, ...
1721 show default-collect
1722 Define a list of expressions to be collected at each tracepoint.
1723 This is a useful way to ensure essential items are not overlooked,
1724 such as registers or a critical global variable.
1726 set disconnected-tracing
1727 show disconnected-tracing
1728 If set to 1, the target is instructed to continue tracing if it
1729 loses its connection to GDB. If 0, the target is to stop tracing
1732 set circular-trace-buffer
1733 show circular-trace-buffer
1734 If set to on, the target is instructed to use a circular trace buffer
1735 and discard the oldest trace frames instead of stopping the trace due
1736 to a full trace buffer. If set to off, the trace stops when the buffer
1737 fills up. Some targets may not support this.
1739 set script-extension off|soft|strict
1740 show script-extension
1741 If set to "off", the debugger does not perform any script language
1742 recognition, and all sourced files are assumed to be GDB scripts.
1743 If set to "soft" (the default), files are sourced according to
1744 filename extension, falling back to GDB scripts if the first
1746 If set to "strict", files are sourced according to filename extension.
1748 set ada trust-PAD-over-XVS on|off
1749 show ada trust-PAD-over-XVS
1750 If off, activate a workaround against a bug in the debugging information
1751 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1752 the GCC sources for more information about the GNAT encoding and
1753 PAD types in particular). It is always safe to set this option to
1754 off, but this introduces a slight performance penalty. The default
1757 * Python API Improvements
1759 ** GDB provides the new class gdb.LazyString. This is useful in
1760 some pretty-printing cases. The new method gdb.Value.lazy_string
1761 provides a simple way to create objects of this type.
1763 ** The fields returned by gdb.Type.fields now have an
1764 `is_base_class' attribute.
1766 ** The new method gdb.Type.range returns the range of an array type.
1768 ** The new method gdb.parse_and_eval can be used to parse and
1769 evaluate an expression.
1771 * New remote packets
1774 Define a trace state variable.
1777 Get the current value of a trace state variable.
1780 Set desired tracing behavior upon disconnection.
1783 Set the trace buffer to be linear or circular.
1786 Get data about the tracepoints currently in use.
1790 Process record now works correctly with hardware watchpoints.
1792 Multiple bug fixes have been made to the mips-irix port, making it
1793 much more reliable. In particular:
1794 - Debugging threaded applications is now possible again. Previously,
1795 GDB would hang while starting the program, or while waiting for
1796 the program to stop at a breakpoint.
1797 - Attaching to a running process no longer hangs.
1798 - An error occurring while loading a core file has been fixed.
1799 - Changing the value of the PC register now works again. This fixes
1800 problems observed when using the "jump" command, or when calling
1801 a function from GDB, or even when assigning a new value to $pc.
1802 - With the "finish" and "return" commands, the return value for functions
1803 returning a small array is now correctly printed.
1804 - It is now possible to break on shared library code which gets executed
1805 during a shared library init phase (code executed while executing
1806 their .init section). Previously, the breakpoint would have no effect.
1807 - GDB is now able to backtrace through the signal handler for
1808 non-threaded programs.
1810 PIE (Position Independent Executable) programs debugging is now supported.
1811 This includes debugging execution of PIC (Position Independent Code) shared
1812 libraries although for that, it should be possible to run such libraries as an
1815 *** Changes in GDB 7.0
1817 * GDB now has an interface for JIT compilation. Applications that
1818 dynamically generate code can create symbol files in memory and register
1819 them with GDB. For users, the feature should work transparently, and
1820 for JIT developers, the interface is documented in the GDB manual in the
1821 "JIT Compilation Interface" chapter.
1823 * Tracepoints may now be conditional. The syntax is as for
1824 breakpoints; either an "if" clause appended to the "trace" command,
1825 or the "condition" command is available. GDB sends the condition to
1826 the target for evaluation using the same bytecode format as is used
1827 for tracepoint actions.
1829 * The disassemble command now supports: an optional /r modifier, print the
1830 raw instructions in hex as well as in symbolic form, and an optional /m
1831 modifier to print mixed source+assembly.
1833 * Process record and replay
1835 In a architecture environment that supports ``process record and
1836 replay'', ``process record and replay'' target can record a log of
1837 the process execution, and replay it with both forward and reverse
1840 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1841 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1842 set execution-direction {forward|reverse}, for targets that support
1845 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1846 feature is available with a native GDB running on kernel version
1849 * GDB now has support for multi-byte and wide character sets on the
1850 target. Strings whose character type is wchar_t, char16_t, or
1851 char32_t are now correctly printed. GDB supports wide- and unicode-
1852 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1853 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1854 `printf'. This feature requires iconv to work properly; if your
1855 system does not have a working iconv, GDB can use GNU libiconv. See
1856 the installation instructions for more information.
1858 * GDB now supports automatic retrieval of shared library files from
1859 remote targets. To use this feature, specify a system root that begins
1860 with the `remote:' prefix, either via the `set sysroot' command or via
1861 the `--with-sysroot' configure-time option.
1863 * "info sharedlibrary" now takes an optional regex of libraries to show,
1864 and it now reports if a shared library has no debugging information.
1866 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1867 now complete on file names.
1869 * When completing in expressions, gdb will attempt to limit
1870 completions to allowable structure or union fields, where appropriate.
1871 For instance, consider:
1873 # struct example { int f1; double f2; };
1874 # struct example variable;
1877 If the user types TAB at the end of this command line, the available
1878 completions will be "f1" and "f2".
1880 * Inlined functions are now supported. They show up in backtraces, and
1881 the "step", "next", and "finish" commands handle them automatically.
1883 * GDB now supports the token-splicing (##) and stringification (#)
1884 operators when expanding macros. It also supports variable-arity
1887 * GDB now supports inspecting extra signal information, exported by
1888 the new $_siginfo convenience variable. The feature is currently
1889 implemented on linux ARM, i386 and amd64.
1891 * GDB can now display the VFP floating point registers and NEON vector
1892 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1893 can provide these registers (requires Linux 2.6.30 or later). Remote
1894 and simulator targets may also provide them.
1896 * New remote packets
1899 Search memory for a sequence of bytes.
1902 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1903 operation over reliable transport links. Use of this packet is
1904 controlled by the `set remote noack-packet' command.
1907 Kill the process with the specified process ID. Use this in preference
1908 to `k' when multiprocess protocol extensions are supported.
1911 Obtains additional operating system information
1915 Read or write additional signal information.
1917 * Removed remote protocol undocumented extension
1919 An undocumented extension to the remote protocol's `S' stop reply
1920 packet that permited the stub to pass a process id was removed.
1921 Remote servers should use the `T' stop reply packet instead.
1923 * GDB now supports multiple function calling conventions according to the
1924 DWARF-2 DW_AT_calling_convention function attribute.
1926 * The SH target utilizes the aforementioned change to distinguish between gcc
1927 and Renesas calling convention. It also adds the new CLI commands
1928 `set/show sh calling-convention'.
1930 * GDB can now read compressed debug sections, as produced by GNU gold
1931 with the --compress-debug-sections=zlib flag.
1933 * 64-bit core files are now supported on AIX.
1935 * Thread switching is now supported on Tru64.
1937 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1938 which will be allocated using malloc later in program execution.
1940 * The qXfer:libraries:read remote procotol packet now allows passing a
1941 list of section offsets.
1943 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1944 conditions handling signals delivered during attach or thread creation
1945 have also been fixed.
1947 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1948 From the user's standpoint, all unqualified instances of True and False
1949 are treated as the standard definitions, regardless of context.
1951 * GDB now parses C++ symbol and type names more flexibly. For
1954 template<typename T> class C { };
1957 GDB will now correctly handle all of:
1959 ptype C<char const *>
1960 ptype C<char const*>
1961 ptype C<const char *>
1962 ptype C<const char*>
1964 * New features in the GDB remote stub, gdbserver
1966 - The "--wrapper" command-line argument tells gdbserver to use a
1967 wrapper program to launch programs for debugging.
1969 - On PowerPC and S/390 targets, it is now possible to use a single
1970 gdbserver executable to debug both 32-bit and 64-bit programs.
1971 (This requires gdbserver itself to be built as a 64-bit executable.)
1973 - gdbserver uses the new noack protocol mode for TCP connections to
1974 reduce communications latency, if also supported and enabled in GDB.
1976 - Support for the sparc64-linux-gnu target is now included in
1979 - The amd64-linux build of gdbserver now supports debugging both
1980 32-bit and 64-bit programs.
1982 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1983 now support hardware watchpoints, and will use them automatically
1988 GDB now has support for scripting using Python. Whether this is
1989 available is determined at configure time.
1991 New GDB commands can now be written in Python.
1993 * Ada tasking support
1995 Ada tasks can now be inspected in GDB. The following commands have
1999 Print the list of Ada tasks.
2001 Print detailed information about task number N.
2003 Print the task number of the current task.
2005 Switch the context of debugging to task number N.
2007 * Support for user-defined prefixed commands. The "define" command can
2008 add new commands to existing prefixes, e.g. "target".
2010 * Multi-inferior, multi-process debugging.
2012 GDB now has generalized support for multi-inferior debugging. See
2013 "Debugging Multiple Inferiors" in the manual for more information.
2014 Although availability still depends on target support, the command
2015 set is more uniform now. The GNU/Linux specific multi-forks support
2016 has been migrated to this new framework. This implied some user
2017 visible changes; see "New commands" and also "Removed commands"
2020 * Target descriptions can now describe the target OS ABI. See the
2021 "Target Description Format" section in the user manual for more
2024 * Target descriptions can now describe "compatible" architectures
2025 to indicate that the target can execute applications for a different
2026 architecture in addition to those for the main target architecture.
2027 See the "Target Description Format" section in the user manual for
2030 * Multi-architecture debugging.
2032 GDB now includes general supports for debugging applications on
2033 hybrid systems that use more than one single processor architecture
2034 at the same time. Each such hybrid architecture still requires
2035 specific support to be added. The only hybrid architecture supported
2036 in this version of GDB is the Cell Broadband Engine.
2038 * GDB now supports integrated debugging of Cell/B.E. applications that
2039 use both the PPU and SPU architectures. To enable support for hybrid
2040 Cell/B.E. debugging, you need to configure GDB to support both the
2041 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2042 --enable-targets configure option.
2044 * Non-stop mode debugging.
2046 For some targets, GDB now supports an optional mode of operation in
2047 which you can examine stopped threads while other threads continue
2048 to execute freely. This is referred to as non-stop mode, with the
2049 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2050 section in the user manual for more information.
2052 To be able to support remote non-stop debugging, a remote stub needs
2053 to implement the non-stop mode remote protocol extensions, as
2054 described in the "Remote Non-Stop" section of the user manual. The
2055 GDB remote stub, gdbserver, has been adjusted to support these
2056 extensions on linux targets.
2058 * New commands (for set/show, see "New options" below)
2060 catch syscall [NAME(S) | NUMBER(S)]
2061 Catch system calls. Arguments, which should be names of system
2062 calls or their numbers, mean catch only those syscalls. Without
2063 arguments, every syscall will be caught. When the inferior issues
2064 any of the specified syscalls, GDB will stop and announce the system
2065 call, both when it is called and when its call returns. This
2066 feature is currently available with a native GDB running on the
2067 Linux Kernel, under the following architectures: x86, x86_64,
2068 PowerPC and PowerPC64.
2070 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2072 Search memory for a sequence of bytes.
2074 maint set python print-stack
2075 maint show python print-stack
2076 Show a stack trace when an error is encountered in a Python script.
2079 Invoke CODE by passing it to the Python interpreter.
2084 These allow macros to be defined, undefined, and listed
2088 Show operating system information about processes.
2091 List the inferiors currently under GDB's control.
2094 Switch focus to inferior number NUM.
2097 Detach from inferior number NUM.
2100 Kill inferior number NUM.
2104 set spu stop-on-load
2105 show spu stop-on-load
2106 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2108 set spu auto-flush-cache
2109 show spu auto-flush-cache
2110 Control whether to automatically flush the software-managed cache
2111 during Cell/B.E. debugging.
2113 set sh calling-convention
2114 show sh calling-convention
2115 Control the calling convention used when calling SH target functions.
2118 show debug timestamp
2119 Control display of timestamps with GDB debugging output.
2121 set disassemble-next-line
2122 show disassemble-next-line
2123 Control display of disassembled source lines or instructions when
2126 set remote noack-packet
2127 show remote noack-packet
2128 Set/show the use of remote protocol QStartNoAckMode packet. See above
2129 under "New remote packets."
2131 set remote query-attached-packet
2132 show remote query-attached-packet
2133 Control use of remote protocol `qAttached' (query-attached) packet.
2135 set remote read-siginfo-object
2136 show remote read-siginfo-object
2137 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2140 set remote write-siginfo-object
2141 show remote write-siginfo-object
2142 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2145 set remote reverse-continue
2146 show remote reverse-continue
2147 Control use of remote protocol 'bc' (reverse-continue) packet.
2149 set remote reverse-step
2150 show remote reverse-step
2151 Control use of remote protocol 'bs' (reverse-step) packet.
2153 set displaced-stepping
2154 show displaced-stepping
2155 Control displaced stepping mode. Displaced stepping is a way to
2156 single-step over breakpoints without removing them from the debuggee.
2157 Also known as "out-of-line single-stepping".
2160 show debug displaced
2161 Control display of debugging info for displaced stepping.
2163 maint set internal-error
2164 maint show internal-error
2165 Control what GDB does when an internal error is detected.
2167 maint set internal-warning
2168 maint show internal-warning
2169 Control what GDB does when an internal warning is detected.
2174 Use a wrapper program to launch programs for debugging.
2176 set multiple-symbols (all|ask|cancel)
2177 show multiple-symbols
2178 The value of this variable can be changed to adjust the debugger behavior
2179 when an expression or a breakpoint location contains an ambiguous symbol
2180 name (an overloaded function name, for instance).
2182 set breakpoint always-inserted
2183 show breakpoint always-inserted
2184 Keep breakpoints always inserted in the target, as opposed to inserting
2185 them when resuming the target, and removing them when the target stops.
2186 This option can improve debugger performance on slow remote targets.
2188 set arm fallback-mode (arm|thumb|auto)
2189 show arm fallback-mode
2190 set arm force-mode (arm|thumb|auto)
2192 These commands control how ARM GDB determines whether instructions
2193 are ARM or Thumb. The default for both settings is auto, which uses
2194 the current CPSR value for instructions without symbols; previous
2195 versions of GDB behaved as if "set arm fallback-mode arm".
2197 set disable-randomization
2198 show disable-randomization
2199 Standalone programs run with the virtual address space randomization enabled
2200 by default on some platforms. This option keeps the addresses stable across
2201 multiple debugging sessions.
2205 Control whether other threads are stopped or not when some thread hits
2210 Requests that asynchronous execution is enabled in the target, if available.
2211 In this case, it's possible to resume target in the background, and interact
2212 with GDB while the target is running. "show target-async" displays the
2213 current state of asynchronous execution of the target.
2215 set target-wide-charset
2216 show target-wide-charset
2217 The target-wide-charset is the name of the character set that GDB
2218 uses when printing characters whose type is wchar_t.
2220 set tcp auto-retry (on|off)
2222 set tcp connect-timeout
2223 show tcp connect-timeout
2224 These commands allow GDB to retry failed TCP connections to a remote stub
2225 with a specified timeout period; this is useful if the stub is launched
2226 in parallel with GDB but may not be ready to accept connections immediately.
2228 set libthread-db-search-path
2229 show libthread-db-search-path
2230 Control list of directories which GDB will search for appropriate
2233 set schedule-multiple (on|off)
2234 show schedule-multiple
2235 Allow GDB to resume all threads of all processes or only threads of
2236 the current process.
2240 Use more aggressive caching for accesses to the stack. This improves
2241 performance of remote debugging (particularly backtraces) without
2242 affecting correctness.
2244 set interactive-mode (on|off|auto)
2245 show interactive-mode
2246 Control whether GDB runs in interactive mode (on) or not (off).
2247 When in interactive mode, GDB waits for the user to answer all
2248 queries. Otherwise, GDB does not wait and assumes the default
2249 answer. When set to auto (the default), GDB determines which
2250 mode to use based on the stdin settings.
2255 For program forks, this is replaced by the new more generic `info
2256 inferiors' command. To list checkpoints, you can still use the
2257 `info checkpoints' command, which was an alias for the `info forks'
2261 Replaced by the new `inferior' command. To switch between
2262 checkpoints, you can still use the `restart' command, which was an
2263 alias for the `fork' command.
2266 This is removed, since some targets don't have a notion of
2267 processes. To switch between processes, you can still use the
2268 `inferior' command using GDB's own inferior number.
2271 For program forks, this is replaced by the new more generic `kill
2272 inferior' command. To delete a checkpoint, you can still use the
2273 `delete checkpoint' command, which was an alias for the `delete
2277 For program forks, this is replaced by the new more generic `detach
2278 inferior' command. To detach a checkpoint, you can still use the
2279 `detach checkpoint' command, which was an alias for the `detach
2282 * New native configurations
2284 x86/x86_64 Darwin i[34567]86-*-darwin*
2286 x86_64 MinGW x86_64-*-mingw*
2290 Lattice Mico32 lm32-*
2291 x86 DICOS i[34567]86-*-dicos*
2292 x86_64 DICOS x86_64-*-dicos*
2295 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2296 (mingw32ce) debugging.
2302 These commands were actually not implemented on any target.
2304 *** Changes in GDB 6.8
2306 * New native configurations
2308 NetBSD/hppa hppa*-*netbsd*
2309 Xtensa GNU/Linux xtensa*-*-linux*
2313 NetBSD/hppa hppa*-*-netbsd*
2314 Xtensa GNU/Lunux xtensa*-*-linux*
2316 * Change in command line behavior -- corefiles vs. process ids.
2318 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2319 attaching to process NUMBER fails, GDB no longer attempts to open a
2320 core file named NUMBER. Attaching to a program using the -c option
2321 is no longer supported. Instead, use the '-p' or '--pid' options.
2323 * GDB can now be built as a native debugger for debugging Windows x86
2324 (mingw32) Portable Executable (PE) programs.
2326 * Pending breakpoints no longer change their number when their address
2329 * GDB now supports breakpoints with multiple locations,
2330 including breakpoints on C++ constructors, inside C++ templates,
2331 and in inlined functions.
2333 * GDB's ability to debug optimized code has been improved. GDB more
2334 accurately identifies function bodies and lexical blocks that occupy
2335 more than one contiguous range of addresses.
2337 * Target descriptions can now describe registers for PowerPC.
2339 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2340 registers on PowerPC targets.
2342 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2343 targets even when the libthread_db library is not available.
2345 * The GDB remote stub, gdbserver, now supports the new file transfer
2346 commands (remote put, remote get, and remote delete).
2348 * The GDB remote stub, gdbserver, now supports run and attach in
2349 extended-remote mode.
2351 * hppa*64*-*-hpux11* target broken
2352 The debugger is unable to start a program and fails with the following
2353 error: "Error trying to get information about dynamic linker".
2354 The gdb-6.7 release is also affected.
2356 * GDB now supports the --enable-targets= configure option to allow
2357 building a single GDB executable that supports multiple remote
2358 target architectures.
2360 * GDB now supports debugging C and C++ programs which use the
2361 Decimal Floating Point extension. In addition, the PowerPC target
2362 now has a set of pseudo-registers to inspect decimal float values
2363 stored in two consecutive float registers.
2365 * The -break-insert MI command can optionally create pending
2368 * Improved support for debugging Ada
2369 Many improvements to the Ada language support have been made. These
2371 - Better support for Ada2005 interface types
2372 - Improved handling of arrays and slices in general
2373 - Better support for Taft-amendment types
2374 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2376 - Improved command completion in Ada
2379 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2384 set print frame-arguments (all|scalars|none)
2385 show print frame-arguments
2386 The value of this variable can be changed to control which argument
2387 values should be printed by the debugger when displaying a frame.
2392 Transfer files to and from a remote target, and delete remote files.
2399 Transfer files to and from a remote target, and delete remote files.
2401 * New remote packets
2408 Open, close, read, write, and delete files on the remote system.
2411 Attach to an existing process on the remote system, in extended-remote
2415 Run a new process on the remote system, in extended-remote mode.
2417 *** Changes in GDB 6.7
2419 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2420 bfd, libiberty and opcodes, as revealed by static analysis donated by
2421 Coverity, Inc. (http://scan.coverity.com).
2423 * When looking up multiply-defined global symbols, GDB will now prefer the
2424 symbol definition in the current shared library if it was built using the
2425 -Bsymbolic linker option.
2427 * When the Text User Interface (TUI) is not configured, GDB will now
2428 recognize the -tui command-line option and print a message that the TUI
2431 * The GDB remote stub, gdbserver, now has lower overhead for high
2432 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2434 * GDB for MIPS targets now autodetects whether a remote target provides
2435 32-bit or 64-bit register values.
2437 * Support for C++ member pointers has been improved.
2439 * GDB now understands XML target descriptions, which specify the
2440 target's overall architecture. GDB can read a description from
2441 a local file or over the remote serial protocol.
2443 * Vectors of single-byte data use a new integer type which is not
2444 automatically displayed as character or string data.
2446 * The /s format now works with the print command. It displays
2447 arrays of single-byte integers and pointers to single-byte integers
2450 * Target descriptions can now describe target-specific registers,
2451 for architectures which have implemented the support (currently
2452 only ARM, M68K, and MIPS).
2454 * GDB and the GDB remote stub, gdbserver, now support the XScale
2457 * The GDB remote stub, gdbserver, has been updated to support
2458 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2459 has been rewritten to use the standard GDB remote protocol.
2461 * GDB can now step into C++ functions which are called through thunks.
2463 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2465 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2466 layout. It also supports a TextSeg= and DataSeg= response when only
2467 segment base addresses (rather than offsets) are available.
2469 * The /i format now outputs any trailing branch delay slot instructions
2470 immediately following the last instruction within the count specified.
2472 * The GDB remote protocol "T" stop reply packet now supports a
2473 "library" response. Combined with the new "qXfer:libraries:read"
2474 packet, this response allows GDB to debug shared libraries on targets
2475 where the operating system manages the list of loaded libraries (e.g.
2476 Windows and SymbianOS).
2478 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2479 (DLLs) on Windows and Windows CE targets.
2481 * GDB now supports a faster verification that a .debug file matches its binary
2482 according to its build-id signature, if the signature is present.
2488 Enable or disable hardware flow control (RTS/CTS) on the serial port
2489 when debugging using remote targets.
2491 set mem inaccessible-by-default
2492 show mem inaccessible-by-default
2493 If the target supplies a memory map, for instance via the remote
2494 protocol's "qXfer:memory-map:read" packet, setting this variable
2495 prevents GDB from accessing memory outside the memory map. This
2496 is useful for targets with memory mapped registers or which react
2497 badly to accesses of unmapped address space.
2499 set breakpoint auto-hw
2500 show breakpoint auto-hw
2501 If the target supplies a memory map, for instance via the remote
2502 protocol's "qXfer:memory-map:read" packet, setting this variable
2503 lets GDB use hardware breakpoints automatically for memory regions
2504 where it can not use software breakpoints. This covers both the
2505 "break" command and internal breakpoints used for other commands
2506 including "next" and "finish".
2509 catch exception unhandled
2510 Stop the program execution when Ada exceptions are raised.
2513 Stop the program execution when an Ada assertion failed.
2517 Set an alternate system root for target files. This is a more
2518 general version of "set solib-absolute-prefix", which is now
2519 an alias to "set sysroot".
2522 Provide extended SPU facility status information. This set of
2523 commands is available only when debugging the Cell/B.E. SPU
2526 * New native configurations
2528 OpenBSD/sh sh*-*openbsd*
2531 unset tdesc filename
2533 Use the specified local file as an XML target description, and do
2534 not query the target for its built-in description.
2538 OpenBSD/sh sh*-*-openbsd*
2539 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2540 Toshiba Media Processor mep-elf
2542 * New remote packets
2545 Ignore the specified signals; pass them directly to the debugged program
2546 without stopping other threads or reporting them to GDB.
2548 qXfer:features:read:
2549 Read an XML target description from the target, which describes its
2554 Read or write contents of an spufs file on the target system. These
2555 packets are available only on the Cell/B.E. SPU architecture.
2557 qXfer:libraries:read:
2558 Report the loaded shared libraries. Combined with new "T" packet
2559 response, this packet allows GDB to debug shared libraries on
2560 targets where the operating system manages the list of loaded
2561 libraries (e.g. Windows and SymbianOS).
2565 Support for these obsolete configurations has been removed.
2573 i[34567]86-*-lynxos*
2574 i[34567]86-*-netware*
2575 i[34567]86-*-sco3.2v5*
2576 i[34567]86-*-sco3.2v4*
2578 i[34567]86-*-sysv4.2*
2581 i[34567]86-*-unixware2*
2582 i[34567]86-*-unixware*
2591 * Other removed features
2598 Various m68k-only ROM monitors.
2605 Various Renesas ROM monitors and debugging interfaces for SH and
2610 Support for a Macraigor serial interface to on-chip debugging.
2611 GDB does not directly support the newer parallel or USB
2616 A debug information format. The predecessor to DWARF 2 and
2617 DWARF 3, which are still supported.
2619 Support for the HP aCC compiler on HP-UX/PA-RISC
2621 SOM-encapsulated symbolic debugging information, automatic
2622 invocation of pxdb, and the aCC custom C++ ABI. This does not
2623 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2624 with aCC can still be debugged on an assembly level.
2626 MIPS ".pdr" sections
2628 A MIPS-specific format used to describe stack frame layout
2629 in debugging information.
2633 GDB could work with an older version of Guile to debug
2634 the interpreter and Scheme programs running in it.
2636 set mips stack-arg-size
2637 set mips saved-gpreg-size
2639 Use "set mips abi" to control parameter passing for MIPS.
2641 *** Changes in GDB 6.6
2646 Cell Broadband Engine SPU spu-elf
2648 * GDB can now be configured as a cross-debugger targeting native Windows
2649 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2650 running on a Windows system over TCP/IP to debug Windows programs.
2652 * The GDB remote stub, gdbserver, has been updated to support Windows and
2653 Cygwin debugging. Both single-threaded and multi-threaded programs are
2656 * The "set trust-readonly-sections" command works again. This command was
2657 broken in GDB 6.3, 6.4, and 6.5.
2659 * The "load" command now supports writing to flash memory, if the remote
2660 stub provides the required support.
2662 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2663 longer requires symbolic debug information (e.g. DWARF-2).
2668 unset substitute-path
2669 show substitute-path
2670 Manage a list of substitution rules that GDB uses to rewrite the name
2671 of the directories where the sources are located. This can be useful
2672 for instance when the sources were moved to a different location
2673 between compilation and debugging.
2677 Print each CLI command as it is executed. Each command is prefixed with
2678 a number of `+' symbols representing the nesting depth.
2679 The source command now has a `-v' option to enable the same feature.
2683 The ARM Demon monitor support (RDP protocol, "target rdp").
2685 Kernel Object Display, an embedded debugging feature which only worked with
2686 an obsolete version of Cisco IOS.
2688 The 'set download-write-size' and 'show download-write-size' commands.
2690 * New remote packets
2693 Tell a stub about GDB client features, and request remote target features.
2694 The first feature implemented is PacketSize, which allows the target to
2695 specify the size of packets it can handle - to minimize the number of
2696 packets required and improve performance when connected to a remote
2700 Fetch an OS auxilliary vector from the remote stub. This packet is a
2701 more efficient replacement for qPart:auxv:read.
2703 qXfer:memory-map:read:
2704 Fetch a memory map from the remote stub, including information about
2705 RAM, ROM, and flash memory devices.
2710 Erase and program a flash memory device.
2712 * Removed remote packets
2715 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2716 used it, and only gdbserver implemented it.
2718 *** Changes in GDB 6.5
2722 Renesas M32C/M16C m32c-elf
2724 Morpho Technologies ms1 ms1-elf
2728 init-if-undefined Initialize a convenience variable, but
2729 only if it doesn't already have a value.
2731 The following commands are presently only implemented for native GNU/Linux:
2733 checkpoint Save a snapshot of the program state.
2735 restart <n> Return the program state to a
2736 previously saved state.
2738 info checkpoints List currently saved checkpoints.
2740 delete-checkpoint <n> Delete a previously saved checkpoint.
2742 set|show detach-on-fork Tell gdb whether to detach from a newly
2743 forked process, or to keep debugging it.
2745 info forks List forks of the user program that
2746 are available to be debugged.
2748 fork <n> Switch to debugging one of several
2749 forks of the user program that are
2750 available to be debugged.
2752 delete-fork <n> Delete a fork from the list of forks
2753 that are available to be debugged (and
2754 kill the forked process).
2756 detach-fork <n> Delete a fork from the list of forks
2757 that are available to be debugged (and
2758 allow the process to continue).
2762 Morpho Technologies ms2 ms1-elf
2764 * Improved Windows host support
2766 GDB now builds as a cross debugger hosted on i686-mingw32, including
2767 native console support, and remote communications using either
2768 network sockets or serial ports.
2770 * Improved Modula-2 language support
2772 GDB can now print most types in the Modula-2 syntax. This includes:
2773 basic types, set types, record types, enumerated types, range types,
2774 pointer types and ARRAY types. Procedure var parameters are correctly
2775 printed and hexadecimal addresses and character constants are also
2776 written in the Modula-2 syntax. Best results can be obtained by using
2777 GNU Modula-2 together with the -gdwarf-2 command line option.
2781 The ARM rdi-share module.
2783 The Netware NLM debug server.
2785 *** Changes in GDB 6.4
2787 * New native configurations
2789 OpenBSD/arm arm*-*-openbsd*
2790 OpenBSD/mips64 mips64-*-openbsd*
2794 Morpho Technologies ms1 ms1-elf
2796 * New command line options
2798 --batch-silent As for --batch, but totally silent.
2799 --return-child-result The debugger will exist with the same value
2800 the child (debugged) program exited with.
2801 --eval-command COMMAND, -ex COMMAND
2802 Execute a single GDB CLI command. This may be
2803 specified multiple times and in conjunction
2804 with the --command (-x) option.
2806 * Deprecated commands removed
2808 The following commands, that were deprecated in 2000, have been
2812 set|show arm disassembly-flavor set|show arm disassembler
2813 othernames set arm disassembler
2814 set|show remotedebug set|show debug remote
2815 set|show archdebug set|show debug arch
2816 set|show eventdebug set|show debug event
2819 * New BSD user-level threads support
2821 It is now possible to debug programs using the user-level threads
2822 library on OpenBSD and FreeBSD. Currently supported (target)
2825 FreeBSD/amd64 x86_64-*-freebsd*
2826 FreeBSD/i386 i386-*-freebsd*
2827 OpenBSD/i386 i386-*-openbsd*
2829 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2830 are not yet supported.
2832 * New support for Matsushita MN10300 w/sim added
2833 (Work in progress). mn10300-elf.
2835 * REMOVED configurations and files
2837 VxWorks and the XDR protocol *-*-vxworks
2838 Motorola MCORE mcore-*-*
2839 National Semiconductor NS32000 ns32k-*-*
2841 * New "set print array-indexes" command
2843 After turning this setting "on", GDB prints the index of each element
2844 when displaying arrays. The default is "off" to preserve the previous
2847 * VAX floating point support
2849 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2851 * User-defined command support
2853 In addition to using $arg0..$arg9 for argument passing, it is now possible
2854 to use $argc to determine now many arguments have been passed. See the
2855 section on user-defined commands in the user manual for more information.
2857 *** Changes in GDB 6.3:
2859 * New command line option
2861 GDB now accepts -l followed by a number to set the timeout for remote
2864 * GDB works with GCC -feliminate-dwarf2-dups
2866 GDB now supports a more compact representation of DWARF-2 debug
2867 information using DW_FORM_ref_addr references. These are produced
2868 by GCC with the option -feliminate-dwarf2-dups and also by some
2869 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2870 to use -feliminate-dwarf2-dups.
2872 * Internationalization
2874 When supported by the host system, GDB will be built with
2875 internationalization (libintl). The task of marking up the sources is
2876 continued, we're looking forward to our first translation.
2880 Initial support for debugging programs compiled with the GNAT
2881 implementation of the Ada programming language has been integrated
2882 into GDB. In this release, support is limited to expression evaluation.
2884 * New native configurations
2886 GNU/Linux/m32r m32r-*-linux-gnu
2890 GDB's remote protocol now includes support for the 'p' packet. This
2891 packet is used to fetch individual registers from a remote inferior.
2893 * END-OF-LIFE registers[] compatibility module
2895 GDB's internal register infrastructure has been completely rewritten.
2896 The new infrastructure making possible the implementation of key new
2897 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2900 GDB 6.3 will be the last release to include the the registers[]
2901 compatibility module that allowed out-of-date configurations to
2902 continue to work. This change directly impacts the following
2912 powerpc bdm protocol
2914 Unless there is activity to revive these configurations, they will be
2915 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2917 * OBSOLETE configurations and files
2919 Configurations that have been declared obsolete in this release have
2920 been commented out. Unless there is activity to revive these
2921 configurations, the next release of GDB will have their sources
2922 permanently REMOVED.
2931 *** Changes in GDB 6.2.1:
2933 * MIPS `break main; run' gave an heuristic-fence-post warning
2935 When attempting to run even a simple program, a warning about
2936 heuristic-fence-post being hit would be reported. This problem has
2939 * MIPS IRIX 'long double' crashed GDB
2941 When examining a long double variable, GDB would get a segmentation
2942 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2943 IRIX long double values).
2947 A bug in the VAX stack code was causing problems with the "next"
2948 command. This problem has been fixed.
2950 *** Changes in GDB 6.2:
2952 * Fix for ``many threads''
2954 On GNU/Linux systems that use the NPTL threads library, a program
2955 rapidly creating and deleting threads would confuse GDB leading to the
2958 ptrace: No such process.
2959 thread_db_get_info: cannot get thread info: generic error
2961 This problem has been fixed.
2963 * "-async" and "-noasync" options removed.
2965 Support for the broken "-noasync" option has been removed (it caused
2968 * New ``start'' command.
2970 This command runs the program until the begining of the main procedure.
2972 * New BSD Kernel Data Access Library (libkvm) interface
2974 Using ``target kvm'' it is now possible to debug kernel core dumps and
2975 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2976 platforms. Currently supported (native-only) configurations are:
2978 FreeBSD/amd64 x86_64-*-freebsd*
2979 FreeBSD/i386 i?86-*-freebsd*
2980 NetBSD/i386 i?86-*-netbsd*
2981 NetBSD/m68k m68*-*-netbsd*
2982 NetBSD/sparc sparc-*-netbsd*
2983 OpenBSD/amd64 x86_64-*-openbsd*
2984 OpenBSD/i386 i?86-*-openbsd*
2985 OpenBSD/m68k m68*-openbsd*
2986 OpenBSD/sparc sparc-*-openbsd*
2988 * Signal trampoline code overhauled
2990 Many generic problems with GDB's signal handling code have been fixed.
2991 These include: backtraces through non-contiguous stacks; recognition
2992 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2993 call; backtrace through a signal trampoline; step into and out of
2994 signal handlers; and single-stepping in the signal trampoline.
2996 Please note that kernel bugs are a limiting factor here. These
2997 features have been shown to work on an s390 GNU/Linux system that
2998 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3000 * Cygwin support for DWARF 2 added.
3002 * New native configurations
3004 GNU/Linux/hppa hppa*-*-linux*
3005 OpenBSD/hppa hppa*-*-openbsd*
3006 OpenBSD/m68k m68*-*-openbsd*
3007 OpenBSD/m88k m88*-*-openbsd*
3008 OpenBSD/powerpc powerpc-*-openbsd*
3009 NetBSD/vax vax-*-netbsd*
3010 OpenBSD/vax vax-*-openbsd*
3012 * END-OF-LIFE frame compatibility module
3014 GDB's internal frame infrastructure has been completely rewritten.
3015 The new infrastructure making it possible to support key new features
3016 including DWARF 2 Call Frame Information. To aid in the task of
3017 migrating old configurations to this new infrastructure, a
3018 compatibility module, that allowed old configurations to continue to
3019 work, was also included.
3021 GDB 6.2 will be the last release to include this frame compatibility
3022 module. This change directly impacts the following configurations:
3032 Unless there is activity to revive these configurations, they will be
3033 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3035 * REMOVED configurations and files
3037 Sun 3, running SunOS 3 m68*-*-sunos3*
3038 Sun 3, running SunOS 4 m68*-*-sunos4*
3039 Sun 2, running SunOS 3 m68000-*-sunos3*
3040 Sun 2, running SunOS 4 m68000-*-sunos4*
3041 Motorola 680x0 running LynxOS m68*-*-lynxos*
3042 AT&T 3b1/Unix pc m68*-att-*
3043 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3044 decstation mips-dec-* mips-little-*
3045 riscos mips-*-riscos* mips-*-sysv*
3046 sonymips mips-sony-*
3047 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3049 *** Changes in GDB 6.1.1:
3051 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3053 The TUI (Text-mode User Interface) is now built as part of a default
3054 GDB configuration. It is enabled by either selecting the TUI with the
3055 command line option "-i=tui" or by running the separate "gdbtui"
3056 program. For more information on the TUI, see the manual "Debugging
3059 * Pending breakpoint support (also included in GDB 6.1)
3061 Support has been added to allow you to specify breakpoints in shared
3062 libraries that have not yet been loaded. If a breakpoint location
3063 cannot be found, and the "breakpoint pending" option is set to auto,
3064 GDB queries you if you wish to make the breakpoint pending on a future
3065 shared-library load. If and when GDB resolves the breakpoint symbol,
3066 the pending breakpoint is removed as one or more regular breakpoints
3069 Pending breakpoints are very useful for GCJ Java debugging.
3071 * Fixed ISO-C build problems
3073 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3074 non ISO-C code that stopped them being built using a more strict ISO-C
3075 compiler (e.g., IBM's C compiler).
3077 * Fixed build problem on IRIX 5
3079 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3080 wasn't able to compile compile on an IRIX 5 system.
3082 * Added execute permission to gdb/gdbserver/configure
3084 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3085 permission. This bug would cause configure to fail on a number of
3086 systems (Solaris, IRIX). Ref: server/519.
3088 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3090 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3091 has been updated to use constant array sizes.
3093 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3095 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3096 its generated DWARF Call Frame Info. This encoding was causing GDB to
3097 panic, that panic has been fixed. Ref: gdb/1628.
3099 * Fixed a problem when examining parameters in shared library code.
3101 When examining parameters in optimized shared library code generated
3102 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3103 not available''. GDB now correctly displays the variable's value.
3105 *** Changes in GDB 6.1:
3107 * Removed --with-mmalloc
3109 Support for the mmalloc memory manager has been removed, as it
3110 conflicted with the internal gdb byte cache.
3112 * Changes in AMD64 configurations
3114 The AMD64 target now includes the %cs and %ss registers. As a result
3115 the AMD64 remote protocol has changed; this affects the floating-point
3116 and SSE registers. If you rely on those registers for your debugging,
3117 you should upgrade gdbserver on the remote side.
3119 * Revised SPARC target
3121 The SPARC target has been completely revised, incorporating the
3122 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3123 support for LynxOS and SunOS 4 has been dropped. Calling functions
3124 from within GDB on operating systems with a non-executable stack
3125 (Solaris, OpenBSD) now works.
3129 GDB has a new C++ demangler which does a better job on the mangled
3130 names generated by current versions of g++. It also runs faster, so
3131 with this and other changes gdb should now start faster on large C++
3134 * DWARF 2 Location Expressions
3136 GDB support for location expressions has been extended to support function
3137 arguments and frame bases. Older versions of GDB could crash when they
3140 * C++ nested types and namespaces
3142 GDB's support for nested types and namespaces in C++ has been
3143 improved, especially if you use the DWARF 2 debugging format. (This
3144 is the default for recent versions of GCC on most platforms.)
3145 Specifically, if you have a class "Inner" defined within a class or
3146 namespace "Outer", then GDB realizes that the class's name is
3147 "Outer::Inner", not simply "Inner". This should greatly reduce the
3148 frequency of complaints about not finding RTTI symbols. In addition,
3149 if you are stopped at inside of a function defined within a namespace,
3150 GDB modifies its name lookup accordingly.
3152 * New native configurations
3154 NetBSD/amd64 x86_64-*-netbsd*
3155 OpenBSD/amd64 x86_64-*-openbsd*
3156 OpenBSD/alpha alpha*-*-openbsd*
3157 OpenBSD/sparc sparc-*-openbsd*
3158 OpenBSD/sparc64 sparc64-*-openbsd*
3160 * New debugging protocols
3162 M32R with SDI protocol m32r-*-elf*
3164 * "set prompt-escape-char" command deleted.
3166 The command "set prompt-escape-char" has been deleted. This command,
3167 and its very obscure effet on GDB's prompt, was never documented,
3168 tested, nor mentioned in the NEWS file.
3170 * OBSOLETE configurations and files
3172 Configurations that have been declared obsolete in this release have
3173 been commented out. Unless there is activity to revive these
3174 configurations, the next release of GDB will have their sources
3175 permanently REMOVED.
3177 Sun 3, running SunOS 3 m68*-*-sunos3*
3178 Sun 3, running SunOS 4 m68*-*-sunos4*
3179 Sun 2, running SunOS 3 m68000-*-sunos3*
3180 Sun 2, running SunOS 4 m68000-*-sunos4*
3181 Motorola 680x0 running LynxOS m68*-*-lynxos*
3182 AT&T 3b1/Unix pc m68*-att-*
3183 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3184 decstation mips-dec-* mips-little-*
3185 riscos mips-*-riscos* mips-*-sysv*
3186 sonymips mips-sony-*
3187 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3189 * REMOVED configurations and files
3191 SGI Irix-4.x mips-sgi-irix4 or iris4
3192 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3193 Z8000 simulator z8k-zilog-none or z8ksim
3194 Matsushita MN10200 w/simulator mn10200-*-*
3195 H8/500 simulator h8500-hitachi-hms or h8500hms
3196 HP/PA running BSD hppa*-*-bsd*
3197 HP/PA running OSF/1 hppa*-*-osf*
3198 HP/PA Pro target hppa*-*-pro*
3199 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3200 386BSD i[3456]86-*-bsd*
3201 Sequent family i[3456]86-sequent-sysv4*
3202 i[3456]86-sequent-sysv*
3203 i[3456]86-sequent-bsd*
3204 SPARC running LynxOS sparc-*-lynxos*
3205 SPARC running SunOS 4 sparc-*-sunos4*
3206 Tsqware Sparclet sparclet-*-*
3207 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3209 *** Changes in GDB 6.0:
3213 Support for debugging the Objective-C programming language has been
3214 integrated into GDB.
3216 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3218 DWARF 2's Call Frame Information makes available compiler generated
3219 information that more exactly describes the program's run-time stack.
3220 By using this information, GDB is able to provide more robust stack
3223 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3224 have been updated to use a new backtrace mechanism which includes
3225 DWARF 2 CFI support.
3229 GDB's remote protocol has been extended to include support for hosted
3230 file I/O (where the remote target uses GDB's file system). See GDB's
3231 remote protocol documentation for details.
3233 * All targets using the new architecture framework.
3235 All of GDB's targets have been updated to use the new internal
3236 architecture framework. The way is now open for future GDB releases
3237 to include cross-architecture native debugging support (i386 on amd64,
3240 * GNU/Linux's Thread Local Storage (TLS)
3242 GDB now includes support for for the GNU/Linux implementation of
3243 per-thread variables.
3245 * GNU/Linux's Native POSIX Thread Library (NPTL)
3247 GDB's thread code has been updated to work with either the new
3248 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3250 * Separate debug info.
3252 GDB, in conjunction with BINUTILS, now supports a mechanism for
3253 automatically loading debug information from a separate file. Instead
3254 of shipping full debug and non-debug versions of system libraries,
3255 system integrators can now instead ship just the stripped libraries
3256 and optional debug files.
3258 * DWARF 2 Location Expressions
3260 DWARF 2 Location Expressions allow the compiler to more completely
3261 describe the location of variables (even in optimized code) to the
3264 GDB now includes preliminary support for location expressions (support
3265 for DW_OP_piece is still missing).
3269 A number of long standing bugs that caused GDB to die while starting a
3270 Java application have been fixed. GDB's Java support is now
3271 considered "useable".
3273 * GNU/Linux support for fork, vfork, and exec.
3275 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3276 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3279 * GDB supports logging output to a file
3281 There are two new commands, "set logging" and "show logging", which can be
3282 used to capture GDB's output to a file.
3284 * The meaning of "detach" has changed for gdbserver
3286 The "detach" command will now resume the application, as documented. To
3287 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3290 * d10v, m68hc11 `regs' command deprecated
3292 The `info registers' command has been updated so that it displays the
3293 registers using a format identical to the old `regs' command.
3297 A new command, "maint set profile on/off", has been added. This command can
3298 be used to enable or disable profiling while running GDB, to profile a
3299 session or a set of commands. In addition there is a new configure switch,
3300 "--enable-profiling", which will cause GDB to be compiled with profiling
3301 data, for more informative profiling results.
3303 * Default MI syntax changed to "mi2".
3305 The default MI (machine interface) syntax, enabled by the command line
3306 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3307 "mi1", can be enabled by specifying the option "-i=mi1".
3309 Support for the original "mi0" syntax (included in GDB 5.0) has been
3312 Fix for gdb/192: removed extraneous space when displaying frame level.
3313 Fix for gdb/672: update changelist is now output in mi list format.
3314 Fix for gdb/702: a -var-assign that updates the value now shows up
3315 in a subsequent -var-update.
3317 * New native configurations.
3319 FreeBSD/amd64 x86_64-*-freebsd*
3321 * Multi-arched targets.
3323 HP/PA HPUX11 hppa*-*-hpux*
3324 Renesas M32R/D w/simulator m32r-*-elf*
3326 * OBSOLETE configurations and files
3328 Configurations that have been declared obsolete in this release have
3329 been commented out. Unless there is activity to revive these
3330 configurations, the next release of GDB will have their sources
3331 permanently REMOVED.
3333 Z8000 simulator z8k-zilog-none or z8ksim
3334 Matsushita MN10200 w/simulator mn10200-*-*
3335 H8/500 simulator h8500-hitachi-hms or h8500hms
3336 HP/PA running BSD hppa*-*-bsd*
3337 HP/PA running OSF/1 hppa*-*-osf*
3338 HP/PA Pro target hppa*-*-pro*
3339 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3340 Sequent family i[3456]86-sequent-sysv4*
3341 i[3456]86-sequent-sysv*
3342 i[3456]86-sequent-bsd*
3343 Tsqware Sparclet sparclet-*-*
3344 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3346 * REMOVED configurations and files
3349 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3350 IBM AIX PS/2 i[3456]86-*-aix
3351 i386 running Mach 3.0 i[3456]86-*-mach3*
3352 i386 running Mach i[3456]86-*-mach*
3353 i386 running OSF/1 i[3456]86-*osf1mk*
3354 HP/Apollo 68k Family m68*-apollo*-sysv*,
3356 m68*-hp-bsd*, m68*-hp-hpux*
3357 Argonaut Risc Chip (ARC) arc-*-*
3358 Mitsubishi D30V d30v-*-*
3359 Fujitsu FR30 fr30-*-elf*
3360 OS/9000 i[34]86-*-os9k
3361 I960 with MON960 i960-*-coff
3363 * MIPS $fp behavior changed
3365 The convenience variable $fp, for the MIPS, now consistently returns
3366 the address of the current frame's base. Previously, depending on the
3367 context, $fp could refer to either $sp or the current frame's base
3368 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3369 The GNU Source-Level Debugger''.
3371 *** Changes in GDB 5.3:
3373 * GNU/Linux shared library multi-threaded performance improved.
3375 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3376 `/proc', in preference to `ptrace' for memory reads. This may result
3377 in an improvement in the start-up time of multi-threaded, shared
3378 library applications when run under GDB. One GDB user writes: ``loads
3379 shared libs like mad''.
3381 * ``gdbserver'' now supports multi-threaded applications on some targets
3383 Support for debugging multi-threaded applications which use
3384 the GNU/Linux LinuxThreads package has been added for
3385 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3386 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3388 * GDB now supports C/C++ preprocessor macros.
3390 GDB now expands preprocessor macro invocations in C/C++ expressions,
3391 and provides various commands for showing macro definitions and how
3394 The new command `macro expand EXPRESSION' expands any macro
3395 invocations in expression, and shows the result.
3397 The new command `show macro MACRO-NAME' shows the definition of the
3398 macro named MACRO-NAME, and where it was defined.
3400 Most compilers don't include information about macros in the debugging
3401 information by default. In GCC 3.1, for example, you need to compile
3402 your program with the options `-gdwarf-2 -g3'. If the macro
3403 information is present in the executable, GDB will read it.
3405 * Multi-arched targets.
3407 DEC Alpha (partial) alpha*-*-*
3408 DEC VAX (partial) vax-*-*
3410 National Semiconductor NS32000 (partial) ns32k-*-*
3411 Motorola 68000 (partial) m68k-*-*
3412 Motorola MCORE mcore-*-*
3416 Fujitsu FRV architecture added by Red Hat frv*-*-*
3419 * New native configurations
3421 Alpha NetBSD alpha*-*-netbsd*
3422 SH NetBSD sh*-*-netbsdelf*
3423 MIPS NetBSD mips*-*-netbsd*
3424 UltraSPARC NetBSD sparc64-*-netbsd*
3426 * OBSOLETE configurations and files
3428 Configurations that have been declared obsolete in this release have
3429 been commented out. Unless there is activity to revive these
3430 configurations, the next release of GDB will have their sources
3431 permanently REMOVED.
3433 Mitsubishi D30V d30v-*-*
3434 OS/9000 i[34]86-*-os9k
3435 IBM AIX PS/2 i[3456]86-*-aix
3436 Fujitsu FR30 fr30-*-elf*
3437 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3438 Argonaut Risc Chip (ARC) arc-*-*
3439 i386 running Mach 3.0 i[3456]86-*-mach3*
3440 i386 running Mach i[3456]86-*-mach*
3441 i386 running OSF/1 i[3456]86-*osf1mk*
3442 HP/Apollo 68k Family m68*-apollo*-sysv*,
3444 m68*-hp-bsd*, m68*-hp-hpux*
3445 I960 with MON960 i960-*-coff
3447 * OBSOLETE languages
3449 CHILL, a Pascal like language used by telecommunications companies.
3451 * REMOVED configurations and files
3453 AMD 29k family via UDI a29k-amd-udi, udi29k
3454 A29K VxWorks a29k-*-vxworks
3455 AMD 29000 embedded, using EBMON a29k-none-none
3456 AMD 29000 embedded with COFF a29k-none-coff
3457 AMD 29000 embedded with a.out a29k-none-aout
3459 testsuite/gdb.hp/gdb.threads-hp/ directory
3461 * New command "set max-user-call-depth <nnn>"
3463 This command allows the user to limit the call depth of user-defined
3464 commands. The default is 1024.
3466 * Changes in FreeBSD/i386 native debugging.
3468 Support for the "generate-core-file" has been added.
3470 * New commands "dump", "append", and "restore".
3472 These commands allow data to be copied from target memory
3473 to a bfd-format or binary file (dump and append), and back
3474 from a file into memory (restore).
3476 * Improved "next/step" support on multi-processor Alpha Tru64.
3478 The previous single-step mechanism could cause unpredictable problems,
3479 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3480 of a software single-step mechanism prevents this.
3482 *** Changes in GDB 5.2.1:
3490 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3491 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3492 Fix, by Joel Brobecker imported from mainline.
3494 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3495 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3496 Fix, by Fred Fish, imported from mainline.
3498 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3499 Surprisingly enough, it works now.
3500 By Michal Ludvig, imported from mainline.
3502 i386 hardware watchpoint support:
3503 avoid misses on second run for some targets.
3504 By Pierre Muller, imported from mainline.
3506 *** Changes in GDB 5.2:
3508 * New command "set trust-readonly-sections on[off]".
3510 This command is a hint that tells gdb that read-only sections
3511 really are read-only (ie. that their contents will not change).
3512 In this mode, gdb will go to the object file rather than the
3513 target to read memory from read-only sections (such as ".text").
3514 This can be a significant performance improvement on some
3515 (notably embedded) targets.
3517 * New command "generate-core-file" (or "gcore").
3519 This new gdb command allows the user to drop a core file of the child
3520 process state at any time. So far it's been implemented only for
3521 GNU/Linux and Solaris, but should be relatively easily ported to other
3522 hosts. Argument is core file name (defaults to core.<pid>).
3524 * New command line option
3526 GDB now accepts --pid or -p followed by a process id.
3528 * Change in command line behavior -- corefiles vs. process ids.
3530 There is a subtle behavior in the way in which GDB handles
3531 command line arguments. The first non-flag argument is always
3532 a program to debug, but the second non-flag argument may either
3533 be a corefile or a process id. Previously, GDB would attempt to
3534 open the second argument as a corefile, and if that failed, would
3535 issue a superfluous error message and then attempt to attach it as
3536 a process. Now, if the second argument begins with a non-digit,
3537 it will be treated as a corefile. If it begins with a digit,
3538 GDB will attempt to attach it as a process, and if no such process
3539 is found, will then attempt to open it as a corefile.
3541 * Changes in ARM configurations.
3543 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3544 configuration is fully multi-arch.
3546 * New native configurations
3548 ARM NetBSD arm*-*-netbsd*
3549 x86 OpenBSD i[3456]86-*-openbsd*
3550 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3551 Sparc64 running FreeBSD sparc64-*-freebsd*
3555 Sanyo XStormy16 xstormy16-elf
3557 * OBSOLETE configurations and files
3559 Configurations that have been declared obsolete in this release have
3560 been commented out. Unless there is activity to revive these
3561 configurations, the next release of GDB will have their sources
3562 permanently REMOVED.
3564 AMD 29k family via UDI a29k-amd-udi, udi29k
3565 A29K VxWorks a29k-*-vxworks
3566 AMD 29000 embedded, using EBMON a29k-none-none
3567 AMD 29000 embedded with COFF a29k-none-coff
3568 AMD 29000 embedded with a.out a29k-none-aout
3570 testsuite/gdb.hp/gdb.threads-hp/ directory
3572 * REMOVED configurations and files
3574 TI TMS320C80 tic80-*-*
3576 PowerPC Solaris powerpcle-*-solaris*
3577 PowerPC Windows NT powerpcle-*-cygwin32
3578 PowerPC Netware powerpc-*-netware*
3579 Harris/CXUX m88k m88*-harris-cxux*
3580 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3581 ns32k-utek-sysv* ns32k-utek-*
3582 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3583 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3584 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3585 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3586 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3588 * Changes to command line processing
3590 The new `--args' feature can be used to specify command-line arguments
3591 for the inferior from gdb's command line.
3593 * Changes to key bindings
3595 There is a new `operate-and-get-next' function bound to `C-o'.
3597 *** Changes in GDB 5.1.1
3599 Fix compile problem on DJGPP.
3601 Fix a problem with floating-point registers on the i386 being
3604 Fix to stop GDB crashing on .debug_str debug info.
3606 Numerous documentation fixes.
3608 Numerous testsuite fixes.
3610 *** Changes in GDB 5.1:
3612 * New native configurations
3614 Alpha FreeBSD alpha*-*-freebsd*
3615 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3616 MIPS GNU/Linux mips*-*-linux*
3617 MIPS SGI Irix 6.x mips*-sgi-irix6*
3618 ia64 AIX ia64-*-aix*
3619 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3623 Motorola 68HC11 and 68HC12 m68hc11-elf
3625 UltraSparc running GNU/Linux sparc64-*-linux*
3627 * OBSOLETE configurations and files
3629 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3630 Harris/CXUX m88k m88*-harris-cxux*
3631 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3632 ns32k-utek-sysv* ns32k-utek-*
3633 TI TMS320C80 tic80-*-*
3635 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3636 PowerPC Solaris powerpcle-*-solaris*
3637 PowerPC Windows NT powerpcle-*-cygwin32
3638 PowerPC Netware powerpc-*-netware*
3639 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3640 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3641 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3642 Apple Macintosh (MPW) host N/A
3644 stuff.c (Program to stuff files into a specially prepared space in kdb)
3645 kdb-start.c (Main loop for the standalone kernel debugger)
3647 Configurations that have been declared obsolete in this release have
3648 been commented out. Unless there is activity to revive these
3649 configurations, the next release of GDB will have their sources
3650 permanently REMOVED.
3652 * REMOVED configurations and files
3654 Altos 3068 m68*-altos-*
3655 Convex c1-*-*, c2-*-*
3657 ARM RISCix arm-*-* (as host)
3661 * GDB has been converted to ISO C.
3663 GDB's source code has been converted to ISO C. In particular, the
3664 sources are fully protoized, and rely on standard headers being
3669 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3671 * The MI enabled by default.
3673 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3674 revised and enabled by default. Packages which use GDB as a debugging
3675 engine behind a UI or another front end are encouraged to switch to
3676 using the GDB/MI interface, instead of the old annotations interface
3677 which is now deprecated.
3679 * Support for debugging Pascal programs.
3681 GDB now includes support for debugging Pascal programs. The following
3682 main features are supported:
3684 - Pascal-specific data types such as sets;
3686 - automatic recognition of Pascal sources based on file-name
3689 - Pascal-style display of data types, variables, and functions;
3691 - a Pascal expression parser.
3693 However, some important features are not yet supported.
3695 - Pascal string operations are not supported at all;
3697 - there are some problems with boolean types;
3699 - Pascal type hexadecimal constants are not supported
3700 because they conflict with the internal variables format;
3702 - support for Pascal objects and classes is not full yet;
3704 - unlike Pascal, GDB is case-sensitive for symbol names.
3706 * Changes in completion.
3708 Commands such as `shell', `run' and `set args', which pass arguments
3709 to inferior programs, now complete on file names, similar to what
3710 users expect at the shell prompt.
3712 Commands which accept locations, such as `disassemble', `print',
3713 `breakpoint', `until', etc. now complete on filenames as well as
3714 program symbols. Thus, if you type "break foob TAB", and the source
3715 files linked into the programs include `foobar.c', that file name will
3716 be one of the candidates for completion. However, file names are not
3717 considered for completion after you typed a colon that delimits a file
3718 name from a name of a function in that file, as in "break foo.c:bar".
3720 `set demangle-style' completes on available demangling styles.
3722 * New platform-independent commands:
3724 It is now possible to define a post-hook for a command as well as a
3725 hook that runs before the command. For more details, see the
3726 documentation of `hookpost' in the GDB manual.
3728 * Changes in GNU/Linux native debugging.
3730 Support for debugging multi-threaded programs has been completely
3731 revised for all platforms except m68k and sparc. You can now debug as
3732 many threads as your system allows you to have.
3734 Attach/detach is supported for multi-threaded programs.
3736 Support for SSE registers was added for x86. This doesn't work for
3737 multi-threaded programs though.
3739 * Changes in MIPS configurations.
3741 Multi-arch support is enabled for all MIPS configurations.
3743 GDB can now be built as native debugger on SGI Irix 6.x systems for
3744 debugging n32 executables. (Debugging 64-bit executables is not yet
3747 * Unified support for hardware watchpoints in all x86 configurations.
3749 Most (if not all) native x86 configurations support hardware-assisted
3750 breakpoints and watchpoints in a unified manner. This support
3751 implements debug register sharing between watchpoints, which allows to
3752 put a virtually infinite number of watchpoints on the same address,
3753 and also supports watching regions up to 16 bytes with several debug
3756 The new maintenance command `maintenance show-debug-regs' toggles
3757 debugging print-outs in functions that insert, remove, and test
3758 watchpoints and hardware breakpoints.
3760 * Changes in the DJGPP native configuration.
3762 New command ``info dos sysinfo'' displays assorted information about
3763 the CPU, OS, memory, and DPMI server.
3765 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3766 display information about segment descriptors stored in GDT, LDT, and
3769 New commands ``info dos pde'' and ``info dos pte'' display entries
3770 from Page Directory and Page Tables (for now works with CWSDPMI only).
3771 New command ``info dos address-pte'' displays the Page Table entry for
3772 a given linear address.
3774 GDB can now pass command lines longer than 126 characters to the
3775 program being debugged (requires an update to the libdbg.a library
3776 which is part of the DJGPP development kit).
3778 DWARF2 debug info is now supported.
3780 It is now possible to `step' and `next' through calls to `longjmp'.
3782 * Changes in documentation.
3784 All GDB documentation was converted to GFDL, the GNU Free
3785 Documentation License.
3787 Tracepoints-related commands are now fully documented in the GDB
3790 TUI, the Text-mode User Interface, is now documented in the manual.
3792 Tracepoints-related commands are now fully documented in the GDB
3795 The "GDB Internals" manual now has an index. It also includes
3796 documentation of `ui_out' functions, GDB coding standards, x86
3797 hardware watchpoints, and memory region attributes.
3799 * GDB's version number moved to ``version.in''
3801 The Makefile variable VERSION has been replaced by the file
3802 ``version.in''. People creating GDB distributions should update the
3803 contents of this file.
3807 GUD support is now a standard part of the EMACS distribution.
3809 *** Changes in GDB 5.0:
3811 * Improved support for debugging FP programs on x86 targets
3813 Unified and much-improved support for debugging floating-point
3814 programs on all x86 targets. In particular, ``info float'' now
3815 displays the FP registers in the same format on all x86 targets, with
3816 greater level of detail.
3818 * Improvements and bugfixes in hardware-assisted watchpoints
3820 It is now possible to watch array elements, struct members, and
3821 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3822 on x86 targets no longer erroneously trigger when the address is
3825 * Improvements in the native DJGPP version of GDB
3827 The distribution now includes all the scripts and auxiliary files
3828 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3829 machines ``out of the box''.
3831 The DJGPP version can now debug programs that use signals. It is
3832 possible to catch signals that happened in the debuggee, deliver
3833 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3834 would kill the program being debugged.) Programs that hook hardware
3835 interrupts (keyboard, timer, etc.) can also be debugged.
3837 It is now possible to debug DJGPP programs that redirect their
3838 standard handles or switch them to raw (as opposed to cooked) mode, or
3839 even close them. The command ``run < foo > bar'' works as expected,
3840 and ``info terminal'' reports useful information about the debuggee's
3841 terminal, including raw/cooked mode, redirection, etc.
3843 The DJGPP version now uses termios functions for console I/O, which
3844 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3847 DOS-style file names with drive letters are now fully supported by
3850 It is now possible to debug DJGPP programs that switch their working
3851 directory. It is also possible to rerun the debuggee any number of
3852 times without restarting GDB; thus, you can use the same setup,
3853 breakpoints, etc. for many debugging sessions.
3855 * New native configurations
3857 ARM GNU/Linux arm*-*-linux*
3858 PowerPC GNU/Linux powerpc-*-linux*
3862 Motorola MCore mcore-*-*
3863 x86 VxWorks i[3456]86-*-vxworks*
3864 PowerPC VxWorks powerpc-*-vxworks*
3865 TI TMS320C80 tic80-*-*
3867 * OBSOLETE configurations
3869 Altos 3068 m68*-altos-*
3870 Convex c1-*-*, c2-*-*
3872 ARM RISCix arm-*-* (as host)
3875 Configurations that have been declared obsolete will be commented out,
3876 but the code will be left in place. If there is no activity to revive
3877 these configurations before the next release of GDB, the sources will
3878 be permanently REMOVED.
3880 * Gould support removed
3882 Support for the Gould PowerNode and NP1 has been removed.
3884 * New features for SVR4
3886 On SVR4 native platforms (such as Solaris), if you attach to a process
3887 without first loading a symbol file, GDB will now attempt to locate and
3888 load symbols from the running process's executable file.
3890 * Many C++ enhancements
3892 C++ support has been greatly improved. Overload resolution now works properly
3893 in almost all cases. RTTI support is on the way.
3895 * Remote targets can connect to a sub-program
3897 A popen(3) style serial-device has been added. This device starts a
3898 sub-process (such as a stand-alone simulator) and then communicates
3899 with that. The sub-program to run is specified using the syntax
3900 ``|<program> <args>'' vis:
3902 (gdb) set remotedebug 1
3903 (gdb) target extended-remote |mn10300-elf-sim program-args
3905 * MIPS 64 remote protocol
3907 A long standing bug in the mips64 remote protocol where by GDB
3908 expected certain 32 bit registers (ex SR) to be transfered as 32
3909 instead of 64 bits has been fixed.
3911 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3912 added to provide backward compatibility with older versions of GDB.
3914 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3916 The command ``set remotebinarydownload'' command has been replaced by
3917 ``set remote X-packet''. Other commands in ``set remote'' family
3918 include ``set remote P-packet''.
3920 * Breakpoint commands accept ranges.
3922 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3923 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3924 ``tracepoint passcount'' also accepts a range of tracepoints.
3926 * ``apropos'' command added.
3928 The ``apropos'' command searches through command names and
3929 documentation strings, printing out matches, making it much easier to
3930 try to find a command that does what you are looking for.
3934 A new machine oriented interface (MI) has been added to GDB. This
3935 interface is designed for debug environments running GDB as a separate
3936 process. This is part of the long term libGDB project. See the
3937 "GDB/MI" chapter of the GDB manual for further information. It can be
3938 enabled by configuring with:
3940 .../configure --enable-gdbmi
3942 *** Changes in GDB-4.18:
3944 * New native configurations
3946 HP-UX 10.20 hppa*-*-hpux10.20
3947 HP-UX 11.x hppa*-*-hpux11.0*
3948 M68K GNU/Linux m68*-*-linux*
3952 Fujitsu FR30 fr30-*-elf*
3953 Intel StrongARM strongarm-*-*
3954 Mitsubishi D30V d30v-*-*
3956 * OBSOLETE configurations
3958 Gould PowerNode, NP1 np1-*-*, pn-*-*
3960 Configurations that have been declared obsolete will be commented out,
3961 but the code will be left in place. If there is no activity to revive
3962 these configurations before the next release of GDB, the sources will
3963 be permanently REMOVED.
3967 As a compatibility experiment, GDB's source files buildsym.h and
3968 buildsym.c have been converted to pure standard C, no longer
3969 containing any K&R compatibility code. We believe that all systems in
3970 use today either come with a standard C compiler, or have a GCC port
3971 available. If this is not true, please report the affected
3973 information about getting a standard C compiler if you don't have one
3978 GDB now uses readline 2.2.
3980 * set extension-language
3982 You can now control the mapping between filename extensions and source
3983 languages by using the `set extension-language' command. For instance,
3984 you can ask GDB to treat .c files as C++ by saying
3985 set extension-language .c c++
3986 The command `info extensions' lists all of the recognized extensions
3987 and their associated languages.
3989 * Setting processor type for PowerPC and RS/6000
3991 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3992 you can use the `set processor' command to specify what variant of the
3993 PowerPC family you are debugging. The command
3997 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3998 following PowerPC and RS6000 variants:
4000 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4001 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4003 403GC IBM PowerPC 403GC
4004 505 Motorola PowerPC 505
4005 860 Motorola PowerPC 860 or 850
4006 601 Motorola PowerPC 601
4007 602 Motorola PowerPC 602
4008 603 Motorola/IBM PowerPC 603 or 603e
4009 604 Motorola PowerPC 604 or 604e
4010 750 Motorola/IBM PowerPC 750 or 750
4012 At the moment, this command just tells GDB what to name the
4013 special-purpose processor registers. Since almost all the affected
4014 registers are inaccessible to user-level programs, this command is
4015 only useful for remote debugging in its present form.
4019 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4020 more extensive support for HP-UX. Added features include shared
4021 library support, kernel threads and hardware watchpoints for 11.00,
4022 support for HP's ANSI C and C++ compilers, and a compatibility mode
4023 for xdb and dbx commands.
4027 HP's donation includes the new concept of catchpoints, which is a
4028 generalization of the old catch command. On HP-UX, it is now possible
4029 to catch exec, fork, and vfork, as well as library loading.
4031 This means that the existing catch command has changed; its first
4032 argument now specifies the type of catch to be set up. See the
4033 output of "help catch" for a list of catchpoint types.
4035 * Debugging across forks
4037 On HP-UX, you can choose which process to debug when a fork() happens
4042 HP has donated a curses-based terminal user interface (TUI). To get
4043 it, build with --enable-tui. Although this can be enabled for any
4044 configuration, at present it only works for native HP debugging.
4046 * GDB remote protocol additions
4048 A new protocol packet 'X' that writes binary data is now available.
4049 Default behavior is to try 'X', then drop back to 'M' if the stub
4050 fails to respond. The settable variable `remotebinarydownload'
4051 allows explicit control over the use of 'X'.
4053 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4054 full 64-bit address. The command
4056 set remoteaddresssize 32
4058 can be used to revert to the old behaviour. For existing remote stubs
4059 the change should not be noticed, as the additional address information
4062 In order to assist in debugging stubs, you may use the maintenance
4063 command `packet' to send any text string to the stub. For instance,
4065 maint packet heythere
4067 sends the packet "$heythere#<checksum>". Note that it is very easy to
4068 disrupt a debugging session by sending the wrong packet at the wrong
4071 The compare-sections command allows you to compare section data on the
4072 target to what is in the executable file without uploading or
4073 downloading, by comparing CRC checksums.
4075 * Tracing can collect general expressions
4077 You may now collect general expressions at tracepoints. This requires
4078 further additions to the target-side stub; see tracepoint.c and
4079 doc/agentexpr.texi for further details.
4081 * mask-address variable for Mips
4083 For Mips targets, you may control the zeroing of the upper 32 bits of
4084 a 64-bit address by entering `set mask-address on'. This is mainly
4085 of interest to users of embedded R4xxx and R5xxx processors.
4087 * Higher serial baud rates
4089 GDB's serial code now allows you to specify baud rates 57600, 115200,
4090 230400, and 460800 baud. (Note that your host system may not be able
4091 to achieve all of these rates.)
4095 The i960 configuration now includes an initial implementation of a
4096 builtin simulator, contributed by Jim Wilson.
4099 *** Changes in GDB-4.17:
4101 * New native configurations
4103 Alpha GNU/Linux alpha*-*-linux*
4104 Unixware 2.x i[3456]86-unixware2*
4105 Irix 6.x mips*-sgi-irix6*
4106 PowerPC GNU/Linux powerpc-*-linux*
4107 PowerPC Solaris powerpcle-*-solaris*
4108 Sparc GNU/Linux sparc-*-linux*
4109 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4113 Argonaut Risc Chip (ARC) arc-*-*
4114 Hitachi H8/300S h8300*-*-*
4115 Matsushita MN10200 w/simulator mn10200-*-*
4116 Matsushita MN10300 w/simulator mn10300-*-*
4117 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4118 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4119 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4120 Mitsubishi D10V w/simulator d10v-*-*
4121 Mitsubishi M32R/D w/simulator m32r-*-elf*
4122 Tsqware Sparclet sparclet-*-*
4123 NEC V850 w/simulator v850-*-*
4125 * New debugging protocols
4127 ARM with RDI protocol arm*-*-*
4128 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4129 DDB and LSI variants of PMON protocol mips*-*-*
4130 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4131 PowerPC with SDS protocol powerpc{,le}-*-eabi
4132 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4136 All configurations can now understand and use the DWARF 2 debugging
4137 format. The choice is automatic, if the symbol file contains DWARF 2
4142 GDB now includes basic Java language support. This support is
4143 only useful with Java compilers that produce native machine code.
4145 * solib-absolute-prefix and solib-search-path
4147 For SunOS and SVR4 shared libraries, you may now set the prefix for
4148 loading absolute shared library symbol files, and the search path for
4149 locating non-absolute shared library symbol files.
4151 * Live range splitting
4153 GDB can now effectively debug code for which GCC has performed live
4154 range splitting as part of its optimization. See gdb/doc/LRS for
4155 more details on the expected format of the stabs information.
4159 GDB's support for the GNU Hurd, including thread debugging, has been
4160 updated to work with current versions of the Hurd.
4164 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4165 instruction set. ARM GDB automatically detects when Thumb
4166 instructions are in use, and adjusts disassembly and backtracing
4171 GDB's MIPS target configurations now handle the MIP16 16-bit
4176 GDB now includes support for overlays; if an executable has been
4177 linked such that multiple sections are based at the same address, GDB
4178 will decide which section to use for symbolic info. You can choose to
4179 control the decision manually, using overlay commands, or implement
4180 additional target-side support and use "overlay load-target" to bring
4181 in the overlay mapping. Do "help overlay" for more detail.
4185 The command "info symbol <address>" displays information about
4186 the symbol at the specified address.
4190 The standard remote protocol now includes an extension that allows
4191 asynchronous collection and display of trace data. This requires
4192 extensive support in the target-side debugging stub. Tracing mode
4193 includes a new interaction mode in GDB and new commands: see the
4194 file tracepoint.c for more details.
4198 Configurations for embedded MIPS now include a simulator contributed
4199 by Cygnus Solutions. The simulator supports the instruction sets
4200 of most MIPS variants.
4204 Sparc configurations may now include the ERC32 simulator contributed
4205 by the European Space Agency. The simulator is not built into
4206 Sparc targets by default; configure with --enable-sim to include it.
4210 For target configurations that may include multiple variants of a
4211 basic architecture (such as MIPS and SH), you may now set the
4212 architecture explicitly. "set arch" sets, "info arch" lists
4213 the possible architectures.
4215 *** Changes in GDB-4.16:
4217 * New native configurations
4219 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4220 M68K NetBSD m68k-*-netbsd*
4221 PowerPC AIX 4.x powerpc-*-aix*
4222 PowerPC MacOS powerpc-*-macos*
4223 PowerPC Windows NT powerpcle-*-cygwin32
4224 RS/6000 AIX 4.x rs6000-*-aix4*
4228 ARM with RDP protocol arm-*-*
4229 I960 with MON960 i960-*-coff
4230 MIPS VxWorks mips*-*-vxworks*
4231 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4232 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4234 Matra Sparclet sparclet-*-*
4238 The powerpc-eabi configuration now includes the PSIM simulator,
4239 contributed by Andrew Cagney, with assistance from Mike Meissner.
4240 PSIM is a very elaborate model of the PowerPC, including not only
4241 basic instruction set execution, but also details of execution unit
4242 performance and I/O hardware. See sim/ppc/README for more details.
4246 GDB now works with Solaris 2.5.
4248 * Windows 95/NT native
4250 GDB will now work as a native debugger on Windows 95 and Windows NT.
4251 To build it from source, you must use the "gnu-win32" environment,
4252 which uses a DLL to emulate enough of Unix to run the GNU tools.
4253 Further information, binaries, and sources are available at
4254 ftp.cygnus.com, under pub/gnu-win32.
4256 * dont-repeat command
4258 If a user-defined command includes the command `dont-repeat', then the
4259 command will not be repeated if the user just types return. This is
4260 useful if the command is time-consuming to run, so that accidental
4261 extra keystrokes don't run the same command many times.
4263 * Send break instead of ^C
4265 The standard remote protocol now includes an option to send a break
4266 rather than a ^C to the target in order to interrupt it. By default,
4267 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4269 * Remote protocol timeout
4271 The standard remote protocol includes a new variable `remotetimeout'
4272 that allows you to set the number of seconds before GDB gives up trying
4273 to read from the target. The default value is 2.
4275 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4277 By default GDB will automatically keep track of objects as they are
4278 loaded and unloaded by the dynamic linker. By using the command `set
4279 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4280 when shared library events occur, thus allowing you to set breakpoints
4281 in shared libraries which are explicitly loaded by the inferior.
4283 Note this feature does not work on hpux8. On hpux9 you must link
4284 /usr/lib/end.o into your program. This feature should work
4285 automatically on hpux10.
4287 * Irix 5.x hardware watchpoint support
4289 Irix 5 configurations now support the use of hardware watchpoints.
4291 * Mips protocol "SYN garbage limit"
4293 When debugging a Mips target using the `target mips' protocol, you
4294 may set the number of characters that GDB will ignore by setting
4295 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4296 every character. The default value is 1050.
4298 * Recording and replaying remote debug sessions
4300 If you set `remotelogfile' to the name of a file, gdb will write to it
4301 a recording of a remote debug session. This recording may then be
4302 replayed back to gdb using "gdbreplay". See gdbserver/README for
4303 details. This is useful when you have a problem with GDB while doing
4304 remote debugging; you can make a recording of the session and send it
4305 to someone else, who can then recreate the problem.
4307 * Speedups for remote debugging
4309 GDB includes speedups for downloading and stepping MIPS systems using
4310 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4311 and more efficient S-record downloading.
4313 * Memory use reductions and statistics collection
4315 GDB now uses less memory and reports statistics about memory usage.
4316 Try the `maint print statistics' command, for example.
4318 *** Changes in GDB-4.15:
4320 * Psymtabs for XCOFF
4322 The symbol reader for AIX GDB now uses partial symbol tables. This
4323 can greatly improve startup time, especially for large executables.
4325 * Remote targets use caching
4327 Remote targets now use a data cache to speed up communication with the
4328 remote side. The data cache could lead to incorrect results because
4329 it doesn't know about volatile variables, thus making it impossible to
4330 debug targets which use memory mapped I/O devices. `set remotecache
4331 off' turns the the data cache off.
4333 * Remote targets may have threads
4335 The standard remote protocol now includes support for multiple threads
4336 in the target system, using new protocol commands 'H' and 'T'. See
4337 gdb/remote.c for details.
4341 If GDB is configured with `--enable-netrom', then it will include
4342 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4343 acts as though it is a bank of ROM on the target board, but you can
4344 write into it over the network. GDB's support consists only of
4345 support for fast loading into the emulated ROM; to debug, you must use
4346 another protocol, such as standard remote protocol. The usual
4347 sequence is something like
4349 target nrom <netrom-hostname>
4351 target remote <netrom-hostname>:1235
4355 GDB now includes support for the Apple Macintosh, as a host only. It
4356 may be run as either an MPW tool or as a standalone application, and
4357 it can debug through the serial port. All the usual GDB commands are
4358 available, but to the target command, you must supply "serial" as the
4359 device type instead of "/dev/ttyXX". See mpw-README in the main
4360 directory for more information on how to build. The MPW configuration
4361 scripts */mpw-config.in support only a few targets, and only the
4362 mips-idt-ecoff target has been tested.
4366 GDB configuration now uses autoconf. This is not user-visible,
4367 but does simplify configuration and building.
4371 GDB now supports hpux10.
4373 *** Changes in GDB-4.14:
4375 * New native configurations
4377 x86 FreeBSD i[345]86-*-freebsd
4378 x86 NetBSD i[345]86-*-netbsd
4379 NS32k NetBSD ns32k-*-netbsd
4380 Sparc NetBSD sparc-*-netbsd
4384 A29K VxWorks a29k-*-vxworks
4385 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4386 CPU32 EST-300 emulator m68*-*-est*
4387 PowerPC ELF powerpc-*-elf
4390 * Alpha OSF/1 support for procfs
4392 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4393 possible to attach to running processes. As the mounting of the /proc
4394 filesystem is optional on the Alpha, GDB automatically determines
4395 the availability of /proc during startup. This can lead to problems
4396 if /proc is unmounted after GDB has been started.
4398 * Arguments to user-defined commands
4400 User commands may accept up to 10 arguments separated by whitespace.
4401 Arguments are accessed within the user command via $arg0..$arg9. A
4404 print $arg0 + $arg1 + $arg2
4406 To execute the command use:
4409 Defines the command "adder" which prints the sum of its three arguments.
4410 Note the arguments are text substitutions, so they may reference variables,
4411 use complex expressions, or even perform inferior function calls.
4413 * New `if' and `while' commands
4415 This makes it possible to write more sophisticated user-defined
4416 commands. Both commands take a single argument, which is the
4417 expression to evaluate, and must be followed by the commands to
4418 execute, one per line, if the expression is nonzero, the list being
4419 terminated by the word `end'. The `if' command list may include an
4420 `else' word, which causes the following commands to be executed only
4421 if the expression is zero.
4423 * Fortran source language mode
4425 GDB now includes partial support for Fortran 77. It will recognize
4426 Fortran programs and can evaluate a subset of Fortran expressions, but
4427 variables and functions may not be handled correctly. GDB will work
4428 with G77, but does not yet know much about symbols emitted by other
4431 * Better HPUX support
4433 Most debugging facilities now work on dynamic executables for HPPAs
4434 running hpux9 or later. You can attach to running dynamically linked
4435 processes, but by default the dynamic libraries will be read-only, so
4436 for instance you won't be able to put breakpoints in them. To change
4437 that behavior do the following before running the program:
4443 This will cause the libraries to be mapped private and read-write.
4444 To revert to the normal behavior, do this:
4450 You cannot set breakpoints or examine data in the library until after
4451 the library is loaded if the function/data symbols do not have
4454 GDB can now also read debug symbols produced by the HP C compiler on
4455 HPPAs (sorry, no C++, Fortran or 68k support).
4457 * Target byte order now dynamically selectable
4459 You can choose which byte order to use with a target system, via the
4460 commands "set endian big" and "set endian little", and you can see the
4461 current setting by using "show endian". You can also give the command
4462 "set endian auto", in which case GDB will use the byte order
4463 associated with the executable. Currently, only embedded MIPS
4464 configurations support dynamic selection of target byte order.
4466 * New DOS host serial code
4468 This version uses DPMI interrupts to handle buffered I/O, so you
4469 no longer need to run asynctsr when debugging boards connected to
4472 *** Changes in GDB-4.13:
4474 * New "complete" command
4476 This lists all the possible completions for the rest of the line, if it
4477 were to be given as a command itself. This is intended for use by emacs.
4479 * Trailing space optional in prompt
4481 "set prompt" no longer adds a space for you after the prompt you set. This
4482 allows you to set a prompt which ends in a space or one that does not.
4484 * Breakpoint hit counts
4486 "info break" now displays a count of the number of times the breakpoint
4487 has been hit. This is especially useful in conjunction with "ignore"; you
4488 can ignore a large number of breakpoint hits, look at the breakpoint info
4489 to see how many times the breakpoint was hit, then run again, ignoring one
4490 less than that number, and this will get you quickly to the last hit of
4493 * Ability to stop printing at NULL character
4495 "set print null-stop" will cause GDB to stop printing the characters of
4496 an array when the first NULL is encountered. This is useful when large
4497 arrays actually contain only short strings.
4499 * Shared library breakpoints
4501 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4502 breakpoints in shared libraries before the executable is run.
4504 * Hardware watchpoints
4506 There is a new hardware breakpoint for the watch command for sparclite
4507 targets. See gdb/sparclite/hw_breakpoint.note.
4509 Hardware watchpoints are also now supported under GNU/Linux.
4513 Annotations have been added. These are for use with graphical interfaces,
4514 and are still experimental. Currently only gdba.el uses these.
4516 * Improved Irix 5 support
4518 GDB now works properly with Irix 5.2.
4520 * Improved HPPA support
4522 GDB now works properly with the latest GCC and GAS.
4524 * New native configurations
4526 Sequent PTX4 i[34]86-sequent-ptx4
4527 HPPA running OSF/1 hppa*-*-osf*
4528 Atari TT running SVR4 m68*-*-sysv4*
4529 RS/6000 LynxOS rs6000-*-lynxos*
4533 OS/9000 i[34]86-*-os9k
4534 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4537 * Hitachi SH7000 and E7000-PC ICE support
4539 There is now support for communicating with the Hitachi E7000-PC ICE.
4540 This is available automatically when GDB is configured for the SH.
4544 As usual, a variety of small fixes and improvements, both generic
4545 and configuration-specific. See the ChangeLog for more detail.
4547 *** Changes in GDB-4.12:
4549 * Irix 5 is now supported
4553 GDB-4.12 on the HPPA has a number of changes which make it unable
4554 to debug the output from the currently released versions of GCC and
4555 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4556 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4557 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4560 *** Changes in GDB-4.11:
4562 * User visible changes:
4566 The "set remotedebug" option is now consistent between the mips remote
4567 target, remote targets using the gdb-specific protocol, UDI (AMD's
4568 debug protocol for the 29k) and the 88k bug monitor. It is now an
4569 integer specifying a debug level (normally 0 or 1, but 2 means more
4570 debugging info for the mips target).
4572 * DEC Alpha native support
4574 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4575 debug info, but GDB works fairly well with the DEC compiler and should
4576 work with a future GCC release. See the README file for a few
4577 Alpha-specific notes.
4579 * Preliminary thread implementation
4581 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4583 * LynxOS native and target support for 386
4585 This release has been hosted on LynxOS 2.2, and also can be configured
4586 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4589 * Improvements in C++ mangling/demangling.
4591 This release has much better g++ debugging, specifically in name
4592 mangling/demangling, virtual function calls, print virtual table,
4593 call methods, ...etc.
4595 *** Changes in GDB-4.10:
4597 * User visible changes:
4599 Remote debugging using the GDB-specific (`target remote') protocol now
4600 supports the `load' command. This is only useful if you have some
4601 other way of getting the stub to the target system, and you can put it
4602 somewhere in memory where it won't get clobbered by the download.
4604 Filename completion now works.
4606 When run under emacs mode, the "info line" command now causes the
4607 arrow to point to the line specified. Also, "info line" prints
4608 addresses in symbolic form (as well as hex).
4610 All vxworks based targets now support a user settable option, called
4611 vxworks-timeout. This option represents the number of seconds gdb
4612 should wait for responses to rpc's. You might want to use this if
4613 your vxworks target is, perhaps, a slow software simulator or happens
4614 to be on the far side of a thin network line.
4618 This release contains support for using a DEC alpha as a GDB host for
4619 cross debugging. Native alpha debugging is not supported yet.
4622 *** Changes in GDB-4.9:
4626 This is the first GDB release which is accompanied by a matching testsuite.
4627 The testsuite requires installation of dejagnu, which should be available
4628 via ftp from most sites that carry GNU software.
4632 'Cfront' style demangling has had its name changed to 'ARM' style, to
4633 emphasize that it was written from the specifications in the C++ Annotated
4634 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4635 disclaimers, it still generated too much confusion with users attempting to
4636 use gdb with AT&T cfront.
4640 GDB now uses a standard remote interface to a simulator library.
4641 So far, the library contains simulators for the Zilog Z8001/2, the
4642 Hitachi H8/300, H8/500 and Super-H.
4644 * New targets supported
4646 H8/300 simulator h8300-hitachi-hms or h8300hms
4647 H8/500 simulator h8500-hitachi-hms or h8500hms
4648 SH simulator sh-hitachi-hms or sh
4649 Z8000 simulator z8k-zilog-none or z8ksim
4650 IDT MIPS board over serial line mips-idt-ecoff
4652 Cross-debugging to GO32 targets is supported. It requires a custom
4653 version of the i386-stub.c module which is integrated with the
4654 GO32 memory extender.
4656 * New remote protocols
4658 MIPS remote debugging protocol.
4660 * New source languages supported
4662 This version includes preliminary support for Chill, a Pascal like language
4663 used by telecommunications companies. Chill support is also being integrated
4664 into the GNU compiler, but we don't know when it will be publically available.
4667 *** Changes in GDB-4.8:
4669 * HP Precision Architecture supported
4671 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4672 version of this support was available as a set of patches from the
4673 University of Utah. GDB does not support debugging of programs
4674 compiled with the HP compiler, because HP will not document their file
4675 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4676 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4678 Many problems in the preliminary version have been fixed.
4680 * Faster and better demangling
4682 We have improved template demangling and fixed numerous bugs in the GNU style
4683 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4684 character types (wchar_t) are now supported. Demangling of each symbol is now
4685 only done once, and is cached when the symbol table for a file is read in.
4686 This results in a small increase in memory usage for C programs, a moderate
4687 increase in memory usage for C++ programs, and a fantastic speedup in
4690 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4691 from the specifications in the Annotated Reference Manual, which AT&T's
4692 compiler does not actually implement.
4694 * G++ multiple inheritance compiler problem
4696 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4697 inheritance lattices was reworked to properly discover ambiguities. We
4698 recently found an example which causes this new algorithm to fail in a
4699 very subtle way, producing bad debug information for those classes.
4700 The file 'gcc.patch' (in this directory) can be applied to gcc to
4701 circumvent the problem. A future GCC release will contain a complete
4704 The previous G++ debug info problem (mentioned below for the gdb-4.7
4705 release) is fixed in gcc version 2.3.2.
4707 * Improved configure script
4709 The `configure' script will now attempt to guess your system type if
4710 you don't supply a host system type. The old scheme of supplying a
4711 host system triplet is preferable over using this. All the magic is
4712 done in the new `config.guess' script. Examine it for details.
4714 We have also brought our configure script much more in line with the FSF's
4715 version. It now supports the --with-xxx options. In particular,
4716 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4717 The resulting GDB will not be able to read arbitrary object file formats --
4718 only the format ``expected'' to be used on the configured target system.
4719 We hope to make this the default in a future release.
4721 * Documentation improvements
4723 There's new internal documentation on how to modify GDB, and how to
4724 produce clean changes to the code. We implore people to read it
4725 before submitting changes.
4727 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4728 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4729 `info' files are also provided. To build `info' files from scratch,
4730 you will need the latest `makeinfo' release, which will be available in
4731 a future texinfo-X.Y release.
4733 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4734 We're not sure exactly which versions have this problem, but it has
4735 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4736 or better. If that isn't possible, there is a patch in
4737 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4738 around this problem.
4742 GDB now supports array constants that can be used in expressions typed in by
4743 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4744 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4747 The new directory `gdb/sparclite' contains a program that demonstrates
4748 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4750 * New native hosts supported
4752 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4753 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4755 * New targets supported
4757 AMD 29k family via UDI a29k-amd-udi or udi29k
4759 * New file formats supported
4761 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4762 HPUX core files, and SCO 3.2v2 core files.
4766 Attaching to processes now works again; thanks for the many bug reports.
4768 We have also stomped on a bunch of core dumps caused by
4769 printf_filtered("%s") problems.
4771 We eliminated a copyright problem on the rpc and ptrace header files
4772 for VxWorks, which was discovered at the last minute during the 4.7
4773 release. You should now be able to build a VxWorks GDB.
4775 You can now interrupt gdb while an attached process is running. This
4776 will cause the attached process to stop, and give control back to GDB.
4778 We fixed problems caused by using too many file descriptors
4779 for reading symbols from object files and libraries. This was
4780 especially a problem for programs that used many (~100) shared
4783 The `step' command now only enters a subroutine if there is line number
4784 information for the subroutine. Otherwise it acts like the `next'
4785 command. Previously, `step' would enter subroutines if there was
4786 any debugging information about the routine. This avoids problems
4787 when using `cc -g1' on MIPS machines.
4789 * Internal improvements
4791 GDB's internal interfaces have been improved to make it easier to support
4792 debugging of multiple languages in the future.
4794 GDB now uses a common structure for symbol information internally.
4795 Minimal symbols (derived from linkage symbols in object files), partial
4796 symbols (from a quick scan of debug information), and full symbols
4797 contain a common subset of information, making it easier to write
4798 shared code that handles any of them.
4800 * New command line options
4802 We now accept --silent as an alias for --quiet.
4806 The memory-mapped-malloc library is now licensed under the GNU Library
4807 General Public License.
4809 *** Changes in GDB-4.7:
4811 * Host/native/target split
4813 GDB has had some major internal surgery to untangle the support for
4814 hosts and remote targets. Now, when you configure GDB for a remote
4815 target, it will no longer load in all of the support for debugging
4816 local programs on the host. When fully completed and tested, this will
4817 ensure that arbitrary host/target combinations are possible.
4819 The primary conceptual shift is to separate the non-portable code in
4820 GDB into three categories. Host specific code is required any time GDB
4821 is compiled on that host, regardless of the target. Target specific
4822 code relates to the peculiarities of the target, but can be compiled on
4823 any host. Native specific code is everything else: it can only be
4824 built when the host and target are the same system. Child process
4825 handling and core file support are two common `native' examples.
4827 GDB's use of /proc for controlling Unix child processes is now cleaner.
4828 It has been split out into a single module under the `target_ops' vector,
4829 plus two native-dependent functions for each system that uses /proc.
4831 * New hosts supported
4833 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4834 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4835 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4837 * New targets supported
4839 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4840 68030 and CPU32 m68030-*-*, m68332-*-*
4842 * New native hosts supported
4844 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4845 (386bsd is not well tested yet)
4846 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4848 * New file formats supported
4850 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4851 supports reading of `a.out.adobe' object files, which are an a.out
4852 format extended with minimal information about multiple sections.
4856 `show copying' is the same as the old `info copying'.
4857 `show warranty' is the same as `info warrantee'.
4858 These were renamed for consistency. The old commands continue to work.
4860 `info handle' is a new alias for `info signals'.
4862 You can now define pre-command hooks, which attach arbitrary command
4863 scripts to any command. The commands in the hook will be executed
4864 prior to the user's command. You can also create a hook which will be
4865 executed whenever the program stops. See gdb.texinfo.
4869 We now deal with Cfront style name mangling, and can even extract type
4870 info from mangled symbols. GDB can automatically figure out which
4871 symbol mangling style your C++ compiler uses.
4873 Calling of methods and virtual functions has been improved as well.
4877 The crash that occured when debugging Sun Ansi-C compiled binaries is
4878 fixed. This was due to mishandling of the extra N_SO stabs output
4881 We also finally got Ultrix 4.2 running in house, and fixed core file
4882 support, with help from a dozen people on the net.
4884 John M. Farrell discovered that the reason that single-stepping was so
4885 slow on all of the Mips based platforms (primarily SGI and DEC) was
4886 that we were trying to demangle and lookup a symbol used for internal
4887 purposes on every instruction that was being stepped through. Changing
4888 the name of that symbol so that it couldn't be mistaken for a C++
4889 mangled symbol sped things up a great deal.
4891 Rich Pixley sped up symbol lookups in general by getting much smarter
4892 about when C++ symbol mangling is necessary. This should make symbol
4893 completion (TAB on the command line) much faster. It's not as fast as
4894 we'd like, but it's significantly faster than gdb-4.6.
4898 A new user controllable variable 'call_scratch_address' can
4899 specify the location of a scratch area to be used when GDB
4900 calls a function in the target. This is necessary because the
4901 usual method of putting the scratch area on the stack does not work
4902 in systems that have separate instruction and data spaces.
4904 We integrated changes to support the 29k UDI (Universal Debugger
4905 Interface), but discovered at the last minute that we didn't have all
4906 of the appropriate copyright paperwork. We are working with AMD to
4907 resolve this, and hope to have it available soon.
4911 We have sped up the remote serial line protocol, especially for targets
4912 with lots of registers. It now supports a new `expedited status' ('T')
4913 message which can be used in place of the existing 'S' status message.
4914 This allows the remote stub to send only the registers that GDB
4915 needs to make a quick decision about single-stepping or conditional
4916 breakpoints, eliminating the need to fetch the entire register set for
4917 each instruction being stepped through.
4919 The GDB remote serial protocol now implements a write-through cache for
4920 registers, only re-reading the registers if the target has run.
4922 There is also a new remote serial stub for SPARC processors. You can
4923 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4924 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4925 processor with a serial port.
4929 Configure.in files have become much easier to read and modify. A new
4930 `table driven' format makes it more obvious what configurations are
4931 supported, and what files each one uses.
4935 There is a new opcodes library which will eventually contain all of the
4936 disassembly routines and opcode tables. At present, it only contains
4937 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4938 disassembler (binutils/objdump) to share these routines.
4940 The libiberty library is now copylefted under the GNU Library General
4941 Public License. This allows more liberal use, and was done so libg++
4942 can use it. This makes no difference to GDB, since the Library License
4943 grants all the rights from the General Public License.
4947 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4948 reference to the stabs symbol info used by the debugger. It is (as far
4949 as we know) the only published document on this fascinating topic. We
4950 encourage you to read it, compare it to the stabs information on your
4951 system, and send improvements on the document in general (to
4954 And, of course, many bugs have been fixed.
4957 *** Changes in GDB-4.6:
4959 * Better support for C++ function names
4961 GDB now accepts as input the "demangled form" of C++ overloaded function
4962 names and member function names, and can do command completion on such names
4963 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4964 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4965 Make use of command completion, it is your friend.
4967 GDB also now accepts a variety of C++ mangled symbol formats. They are
4968 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4969 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4970 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4971 for the list of formats.
4973 * G++ symbol mangling problem
4975 Recent versions of gcc have a bug in how they emit debugging information for
4976 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4977 directory) can be applied to gcc to fix the problem. Alternatively, if you
4978 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4979 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4980 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4983 * New 'maintenance' command
4985 All of the commands related to hacking GDB internals have been moved out of
4986 the main command set, and now live behind the 'maintenance' command. This
4987 can also be abbreviated as 'mt'. The following changes were made:
4989 dump-me -> maintenance dump-me
4990 info all-breakpoints -> maintenance info breakpoints
4991 printmsyms -> maintenance print msyms
4992 printobjfiles -> maintenance print objfiles
4993 printpsyms -> maintenance print psymbols
4994 printsyms -> maintenance print symbols
4996 The following commands are new:
4998 maintenance demangle Call internal GDB demangler routine to
4999 demangle a C++ link name and prints the result.
5000 maintenance print type Print a type chain for a given symbol
5002 * Change to .gdbinit file processing
5004 We now read the $HOME/.gdbinit file before processing the argv arguments
5005 (e.g. reading symbol files or core files). This allows global parameters to
5006 be set, which will apply during the symbol reading. The ./.gdbinit is still
5007 read after argv processing.
5009 * New hosts supported
5011 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5013 GNU/Linux support i386-unknown-linux or linux
5015 We are also including code to support the HP/PA running BSD and HPUX. This
5016 is almost guaranteed not to work, as we didn't have time to test or build it
5017 for this release. We are including it so that the more adventurous (or
5018 masochistic) of you can play with it. We also had major problems with the
5019 fact that the compiler that we got from HP doesn't support the -g option.
5022 * New targets supported
5024 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5026 * More smarts about finding #include files
5028 GDB now remembers the compilation directory for all include files, and for
5029 all files from which C is generated (like yacc and lex sources). This
5030 greatly improves GDB's ability to find yacc/lex sources, and include files,
5031 especially if you are debugging your program from a directory different from
5032 the one that contains your sources.
5034 We also fixed a bug which caused difficulty with listing and setting
5035 breakpoints in include files which contain C code. (In the past, you had to
5036 try twice in order to list an include file that you hadn't looked at before.)
5038 * Interesting infernals change
5040 GDB now deals with arbitrary numbers of sections, where the symbols for each
5041 section must be relocated relative to that section's landing place in the
5042 target's address space. This work was needed to support ELF with embedded
5043 stabs used by Solaris-2.0.
5045 * Bug fixes (of course!)
5047 There have been loads of fixes for the following things:
5048 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5049 i960, stabs, DOS(GO32), procfs, etc...
5051 See the ChangeLog for details.
5053 *** Changes in GDB-4.5:
5055 * New machines supported (host and target)
5057 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5059 SGI Irix-4.x mips-sgi-irix4 or iris4
5061 * New malloc package
5063 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5064 Mmalloc is capable of handling mutiple heaps of memory. It is also
5065 capable of saving a heap to a file, and then mapping it back in later.
5066 This can be used to greatly speedup the startup of GDB by using a
5067 pre-parsed symbol table which lives in a mmalloc managed heap. For
5068 more details, please read mmalloc/mmalloc.texi.
5072 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5073 'help info proc' for details.
5075 * MIPS ecoff symbol table format
5077 The code that reads MIPS symbol table format is now supported on all hosts.
5078 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5081 * File name changes for MS-DOS
5083 Many files in the config directories have been renamed to make it easier to
5084 support GDB on MS-DOSe systems (which have very restrictive file name
5085 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5086 environment) is close to working but has some remaining problems. Note
5087 that debugging of DOS programs is not supported, due to limitations
5088 in the ``operating system'', but it can be used to host cross-debugging.
5090 * Cross byte order fixes
5092 Many fixes have been made to support cross debugging of Sparc and MIPS
5093 targets from hosts whose byte order differs.
5095 * New -mapped and -readnow options
5097 If memory-mapped files are available on your system through the 'mmap'
5098 system call, you can use the -mapped option on the `file' or
5099 `symbol-file' commands to cause GDB to write the symbols from your
5100 program into a reusable file. If the program you are debugging is
5101 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5102 Future GDB debugging sessions will notice the presence of this file,
5103 and will quickly map in symbol information from it, rather than reading
5104 the symbol table from the executable program. Using the '-mapped'
5105 option in a GDB `file' or `symbol-file' command has the same effect as
5106 starting GDB with the '-mapped' command-line option.
5108 You can cause GDB to read the entire symbol table immediately by using
5109 the '-readnow' option with any of the commands that load symbol table
5110 information (or on the GDB command line). This makes the command
5111 slower, but makes future operations faster.
5113 The -mapped and -readnow options are typically combined in order to
5114 build a `fred.syms' file that contains complete symbol information.
5115 A simple GDB invocation to do nothing but build a `.syms' file for future
5118 gdb -batch -nx -mapped -readnow programname
5120 The `.syms' file is specific to the host machine on which GDB is run.
5121 It holds an exact image of GDB's internal symbol table. It cannot be
5122 shared across multiple host platforms.
5124 * longjmp() handling
5126 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5127 siglongjmp() without losing control. This feature has not yet been ported to
5128 all systems. It currently works on many 386 platforms, all MIPS-based
5129 platforms (SGI, DECstation, etc), and Sun3/4.
5133 Preliminary work has been put in to support the new Solaris OS from Sun. At
5134 this time, it can control and debug processes, but it is not capable of
5139 As always, many many bug fixes. The major areas were with g++, and mipsread.
5140 People using the MIPS-based platforms should experience fewer mysterious
5141 crashes and trashed symbol tables.
5143 *** Changes in GDB-4.4:
5145 * New machines supported (host and target)
5147 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5149 BSD Reno on Vax vax-dec-bsd
5150 Ultrix on Vax vax-dec-ultrix
5152 * New machines supported (target)
5154 AMD 29000 embedded, using EBMON a29k-none-none
5158 GDB continues to improve its handling of C++. `References' work better.
5159 The demangler has also been improved, and now deals with symbols mangled as
5160 per the Annotated C++ Reference Guide.
5162 GDB also now handles `stabs' symbol information embedded in MIPS
5163 `ecoff' symbol tables. Since the ecoff format was not easily
5164 extensible to handle new languages such as C++, this appeared to be a
5165 good way to put C++ debugging info into MIPS binaries. This option
5166 will be supported in the GNU C compiler, version 2, when it is
5169 * New features for SVR4
5171 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5172 shared libraries. Debugging dynamically linked programs should present
5173 only minor differences from debugging statically linked programs.
5175 The `info proc' command will print out information about any process
5176 on an SVR4 system (including the one you are debugging). At the moment,
5177 it prints the address mappings of the process.
5179 If you bring up GDB on another SVR4 system, please send mail to
5182 * Better dynamic linking support in SunOS
5184 Reading symbols from shared libraries which contain debugging symbols
5185 now works properly. However, there remain issues such as automatic
5186 skipping of `transfer vector' code during function calls, which
5187 make it harder to debug code in a shared library, than to debug the
5188 same code linked statically.
5192 GDB is now using the latest `getopt' routines from the FSF. This
5193 version accepts the -- prefix for options with long names. GDB will
5194 continue to accept the old forms (-option and +option) as well.
5195 Various single letter abbreviations for options have been explicity
5196 added to the option table so that they won't get overshadowed in the
5197 future by other options that begin with the same letter.
5201 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5202 Many assorted bugs have been handled. Many more remain to be handled.
5203 See the various ChangeLog files (primarily in gdb and bfd) for details.
5206 *** Changes in GDB-4.3:
5208 * New machines supported (host and target)
5210 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5211 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5212 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5214 * Almost SCO Unix support
5216 We had hoped to support:
5217 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5218 (except for core file support), but we discovered very late in the release
5219 that it has problems with process groups that render gdb unusable. Sorry
5220 about that. I encourage people to fix it and post the fixes.
5222 * Preliminary ELF and DWARF support
5224 GDB can read ELF object files on System V Release 4, and can handle
5225 debugging records for C, in DWARF format, in ELF files. This support
5226 is preliminary. If you bring up GDB on another SVR4 system, please
5232 GDB now uses the latest `readline' library. One user-visible change
5233 is that two tabs will list possible command completions, which previously
5234 required typing M-? (meta-question mark, or ESC ?).
5238 The `stepi' bug that many of you noticed has been squashed.
5239 Many bugs in C++ have been handled. Many more remain to be handled.
5240 See the various ChangeLog files (primarily in gdb and bfd) for details.
5242 * State of the MIPS world (in case you wondered):
5244 GDB can understand the symbol tables emitted by the compilers
5245 supplied by most vendors of MIPS-based machines, including DEC. These
5246 symbol tables are in a format that essentially nobody else uses.
5248 Some versions of gcc come with an assembler post-processor called
5249 mips-tfile. This program is required if you want to do source-level
5250 debugging of gcc-compiled programs. I believe FSF does not ship
5251 mips-tfile with gcc version 1, but it will eventually come with gcc
5254 Debugging of g++ output remains a problem. g++ version 1.xx does not
5255 really support it at all. (If you're lucky, you should be able to get
5256 line numbers and stack traces to work, but no parameters or local
5257 variables.) With some work it should be possible to improve the
5260 When gcc version 2 is released, you will have somewhat better luck.
5261 However, even then you will get confusing results for inheritance and
5264 We will eventually provide full debugging of g++ output on
5265 DECstations. This will probably involve some kind of stabs-in-ecoff
5266 encapulation, but the details have not been worked out yet.
5269 *** Changes in GDB-4.2:
5271 * Improved configuration
5273 Only one copy of `configure' exists now, and it is not self-modifying.
5274 Porting BFD is simpler.
5278 The `step' and `next' commands now only stop at the first instruction
5279 of a source line. This prevents the multiple stops that used to occur
5280 in switch statements, for-loops, etc. `Step' continues to stop if a
5281 function that has debugging information is called within the line.
5285 Lots of small bugs fixed. More remain.
5287 * New host supported (not target)
5289 Intel 386 PC clone running Mach i386-none-mach
5292 *** Changes in GDB-4.1:
5294 * Multiple source language support
5296 GDB now has internal scaffolding to handle several source languages.
5297 It determines the type of each source file from its filename extension,
5298 and will switch expression parsing and number formatting to match the
5299 language of the function in the currently selected stack frame.
5300 You can also specifically set the language to be used, with
5301 `set language c' or `set language modula-2'.
5305 GDB now has preliminary support for the GNU Modula-2 compiler,
5306 currently under development at the State University of New York at
5307 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5308 continue through the fall of 1991 and into 1992.
5310 Other Modula-2 compilers are currently not supported, and attempting to
5311 debug programs compiled with them will likely result in an error as the
5312 symbol table is read. Feel free to work on it, though!
5314 There are hooks in GDB for strict type checking and range checking,
5315 in the `Modula-2 philosophy', but they do not currently work.
5319 GDB can now write to executable and core files (e.g. patch
5320 a variable's value). You must turn this switch on, specify
5321 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5322 by assigning a new value to a variable. Modifications take
5325 * Automatic SunOS shared library reading
5327 When you run your program, GDB automatically determines where its
5328 shared libraries (if any) have been loaded, and reads their symbols.
5329 The `share' command is no longer needed. This also works when
5330 examining core files.
5334 You can specify the number of lines that the `list' command shows.
5337 * New machines supported (host and target)
5339 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5340 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5341 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5343 * New hosts supported (not targets)
5345 IBM RT/PC: romp-ibm-aix or rtpc
5347 * New targets supported (not hosts)
5349 AMD 29000 embedded with COFF a29k-none-coff
5350 AMD 29000 embedded with a.out a29k-none-aout
5351 Ultracomputer remote kernel debug a29k-nyu-kern
5353 * New remote interfaces
5359 *** Changes in GDB-4.0:
5363 Wide output is wrapped at good places to make the output more readable.
5365 Gdb now supports cross-debugging from a host machine of one type to a
5366 target machine of another type. Communication with the target system
5367 is over serial lines. The ``target'' command handles connecting to the
5368 remote system; the ``load'' command will download a program into the
5369 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5370 also supports debugging of realtime processes running under VxWorks,
5371 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5372 stub on the target system.
5374 New CPUs supported include the AMD 29000 and Intel 960.
5376 GDB now reads object files and symbol tables via a ``binary file''
5377 library, which allows a single copy of GDB to debug programs of multiple
5378 object file types such as a.out and coff.
5380 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5381 refcard.dvi and refcard.ps are available to format it).
5384 * Control-Variable user interface simplified
5386 All variables that control the operation of the debugger can be set
5387 by the ``set'' command, and displayed by the ``show'' command.
5389 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5390 ``Show prompt'' produces the response:
5391 Gdb's prompt is new-gdb=>.
5393 What follows are the NEW set commands. The command ``help set'' will
5394 print a complete list of old and new set commands. ``help set FOO''
5395 will give a longer description of the variable FOO. ``show'' will show
5396 all of the variable descriptions and their current settings.
5398 confirm on/off: Enables warning questions for operations that are
5399 hard to recover from, e.g. rerunning the program while
5400 it is already running. Default is ON.
5402 editing on/off: Enables EMACS style command line editing
5403 of input. Previous lines can be recalled with
5404 control-P, the current line can be edited with control-B,
5405 you can search for commands with control-R, etc.
5408 history filename NAME: NAME is where the gdb command history
5409 will be stored. The default is .gdb_history,
5410 or the value of the environment variable
5413 history size N: The size, in commands, of the command history. The
5414 default is 256, or the value of the environment variable
5417 history save on/off: If this value is set to ON, the history file will
5418 be saved after exiting gdb. If set to OFF, the
5419 file will not be saved. The default is OFF.
5421 history expansion on/off: If this value is set to ON, then csh-like
5422 history expansion will be performed on
5423 command line input. The default is OFF.
5425 radix N: Sets the default radix for input and output. It can be set
5426 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5427 in the current radix, so "set radix 10" is always a no-op.
5429 height N: This integer value is the number of lines on a page. Default
5430 is 24, the current `stty rows'' setting, or the ``li#''
5431 setting from the termcap entry matching the environment
5434 width N: This integer value is the number of characters on a line.
5435 Default is 80, the current `stty cols'' setting, or the ``co#''
5436 setting from the termcap entry matching the environment
5439 Note: ``set screensize'' is obsolete. Use ``set height'' and
5440 ``set width'' instead.
5442 print address on/off: Print memory addresses in various command displays,
5443 such as stack traces and structure values. Gdb looks
5444 more ``symbolic'' if you turn this off; it looks more
5445 ``machine level'' with it on. Default is ON.
5447 print array on/off: Prettyprint arrays. New convenient format! Default
5450 print demangle on/off: Print C++ symbols in "source" form if on,
5453 print asm-demangle on/off: Same, for assembler level printouts
5456 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5459 * Support for Epoch Environment.
5461 The epoch environment is a version of Emacs v18 with windowing. One
5462 new command, ``inspect'', is identical to ``print'', except that if you
5463 are running in the epoch environment, the value is printed in its own
5467 * Support for Shared Libraries
5469 GDB can now debug programs and core files that use SunOS shared libraries.
5470 Symbols from a shared library cannot be referenced
5471 before the shared library has been linked with the program (this
5472 happens after you type ``run'' and before the function main() is entered).
5473 At any time after this linking (including when examining core files
5474 from dynamically linked programs), gdb reads the symbols from each
5475 shared library when you type the ``sharedlibrary'' command.
5476 It can be abbreviated ``share''.
5478 sharedlibrary REGEXP: Load shared object library symbols for files
5479 matching a unix regular expression. No argument
5480 indicates to load symbols for all shared libraries.
5482 info sharedlibrary: Status of loaded shared libraries.
5487 A watchpoint stops execution of a program whenever the value of an
5488 expression changes. Checking for this slows down execution
5489 tremendously whenever you are in the scope of the expression, but is
5490 quite useful for catching tough ``bit-spreader'' or pointer misuse
5491 problems. Some machines such as the 386 have hardware for doing this
5492 more quickly, and future versions of gdb will use this hardware.
5494 watch EXP: Set a watchpoint (breakpoint) for an expression.
5496 info watchpoints: Information about your watchpoints.
5498 delete N: Deletes watchpoint number N (same as breakpoints).
5499 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5500 enable N: Re-enables watchpoint number N (same as breakpoints).
5503 * C++ multiple inheritance
5505 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5508 * C++ exception handling
5510 Gdb now supports limited C++ exception handling. Besides the existing
5511 ability to breakpoint on an exception handler, gdb can breakpoint on
5512 the raising of an exception (before the stack is peeled back to the
5515 catch FOO: If there is a FOO exception handler in the dynamic scope,
5516 set a breakpoint to catch exceptions which may be raised there.
5517 Multiple exceptions (``catch foo bar baz'') may be caught.
5519 info catch: Lists all exceptions which may be caught in the
5520 current stack frame.
5523 * Minor command changes
5525 The command ``call func (arg, arg, ...)'' now acts like the print
5526 command, except it does not print or save a value if the function's result
5527 is void. This is similar to dbx usage.
5529 The ``up'' and ``down'' commands now always print the frame they end up
5530 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5531 frames without printing.
5533 * New directory command
5535 'dir' now adds directories to the FRONT of the source search path.
5536 The path starts off empty. Source files that contain debug information
5537 about the directory in which they were compiled can be found even
5538 with an empty path; Sun CC and GCC include this information. If GDB can't
5539 find your source file in the current directory, type "dir .".
5541 * Configuring GDB for compilation
5543 For normal use, type ``./configure host''. See README or gdb.texinfo
5546 GDB now handles cross debugging. If you are remotely debugging between
5547 two different machines, type ``./configure host -target=targ''.
5548 Host is the machine where GDB will run; targ is the machine
5549 where the program that you are debugging will run.