1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
8 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
10 * GDB now supports Fission DWP file format version 2.
11 http://gcc.gnu.org/wiki/DebugFission
13 * New convenience function "$_isvoid", to check whether an expression
14 is void. A void expression is an expression where the type of the
15 result is "void". For example, some convenience variables may be
16 "void" when evaluated (e.g., "$_exitcode" before the execution of
17 the program being debugged; or an undefined convenience variable).
18 Another example, when calling a function whose return type is
21 * The "maintenance print objfiles" command now takes an optional regexp.
23 * The "catch syscall" command now works on arm*-linux* targets.
25 * GDB now consistently shows "<not saved>" when printing values of
26 registers the debug info indicates have not been saved in the frame
27 and there's nowhere to retrieve them from
28 (callee-saved/call-clobbered registers):
33 (gdb) info registers rax
36 Before, the former would print "<optimized out>", and the latter
37 "*value not available*".
39 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
44 ** Frame filters and frame decorators have been added.
45 ** Temporary breakpoints are now supported.
46 ** Line tables representation has been added.
47 ** New attribute 'parent_type' for gdb.Field objects.
48 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
49 ** New attribute 'name' for gdb.Type objects.
53 Nios II ELF nios2*-*-elf
54 Nios II GNU/Linux nios2*-*-linux
55 Texas Instruments MSP430 msp430*-*-elf
57 * Removed native configurations
59 Support for these a.out NetBSD and OpenBSD obsolete configurations has
60 been removed. ELF variants of these configurations are kept supported.
62 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
63 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
64 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
65 i[34567]86-*-openbsd3.[0-3]
66 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
67 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
68 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
72 Like "catch throw", but catches a re-thrown exception.
74 Renamed from old "maint check-symtabs".
76 Perform consistency checks on symtabs.
78 Expand symtabs matching an optional regexp.
81 Display the details of GDB configure-time options.
83 maint set|show per-command
84 maint set|show per-command space
85 maint set|show per-command time
86 maint set|show per-command symtab
87 Enable display of per-command gdb resource usage.
89 remove-symbol-file FILENAME
90 remove-symbol-file -a ADDRESS
91 Remove a symbol file added via add-symbol-file. The file to remove
92 can be identified by its filename or by an address that lies within
93 the boundaries of this symbol file in memory.
96 info exceptions REGEXP
97 Display the list of Ada exceptions defined in the program being
98 debugged. If provided, only the exceptions whose names match REGEXP
103 set debug symfile off|on
105 Control display of debugging info regarding reading symbol files and
106 symbol tables within those files
108 set print raw frame-arguments
109 show print raw frame-arguments
110 Set/show whether to print frame arguments in raw mode,
111 disregarding any defined pretty-printers.
113 set remote trace-status-packet
114 show remote trace-status-packet
115 Set/show the use of remote protocol qTStatus packet.
119 Control display of debugging messages related to Nios II targets.
123 Control whether target-assisted range stepping is enabled.
125 set startup-with-shell
126 show startup-with-shell
127 Specifies whether Unix child processes are started via a shell or
132 Use the target memory cache for accesses to the code segment. This
133 improves performance of remote debugging (particularly disassembly).
135 * You can now use a literal value 'unlimited' for options that
136 interpret 0 or -1 as meaning "unlimited". E.g., "set
137 trace-buffer-size unlimited" is now an alias for "set
138 trace-buffer-size -1" and "set height unlimited" is now an alias for
141 * The "set debug symtab-create" debugging option of GDB has been changed to
142 accept a verbosity level. 0 means "off", 1 provides basic debugging
143 output, and values of 2 or greater provides more verbose output.
145 * New command-line options
147 Display the details of GDB configure-time options.
149 * The command 'tsave' can now support new option '-ctf' to save trace
150 buffer in Common Trace Format.
152 * Newly installed $prefix/bin/gcore acts as a shell interface for the
155 * GDB now implements the the C++ 'typeid' operator.
157 * The new convenience variable $_exception holds the exception being
158 thrown or caught at an exception-related catchpoint.
160 * The exception-related catchpoints, like "catch throw", now accept a
161 regular expression which can be used to filter exceptions by type.
163 * The new convenience variable $_exitsignal is automatically set to
164 the terminating signal number when the program being debugged dies
165 due to an uncaught signal.
169 ** All MI commands now accept an optional "--language" option.
170 Support for this feature can be verified by using the "-list-features"
171 command, which should contain "language-option".
173 ** The new command -info-gdb-mi-command allows the user to determine
174 whether a GDB/MI command is supported or not.
176 ** The "^error" result record returned when trying to execute an undefined
177 GDB/MI command now provides a variable named "code" whose content is the
178 "undefined-command" error code. Support for this feature can be verified
179 by using the "-list-features" command, which should contain
180 "undefined-command-error-code".
182 ** The -trace-save MI command can optionally save trace buffer in Common
185 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
187 ** The command -data-list-register-values now accepts an optional
188 "--skip-unavailable" option. When used, only the available registers
191 ** The new command -trace-frame-collected dumps collected variables,
192 computed expressions, tvars, memory and registers in a traceframe.
194 ** The commands -stack-list-locals, -stack-list-arguments and
195 -stack-list-variables now accept an option "--skip-unavailable".
196 When used, only the available locals or arguments are displayed.
198 ** The -exec-run command now accepts an optional "--start" option.
199 When used, the command follows the same semantics as the "start"
200 command, stopping the program's execution at the start of its
201 main subprogram. Support for this feature can be verified using
202 the "-list-features" command, which should contain
203 "exec-run-start-option".
205 ** The new commands -catch-assert and -catch-exceptions insert
206 catchpoints stopping the program when Ada exceptions are raised.
208 ** The new command -info-ada-exceptions provides the equivalent of
209 the new "info exceptions" command.
211 * New system-wide configuration scripts
212 A GDB installation now provides scripts suitable for use as system-wide
213 configuration scripts for the following systems:
217 * GDB now supports target-assigned range stepping with remote targets.
218 This improves the performance of stepping source lines by reducing
219 the number of control packets from/to GDB. See "New remote packets"
222 * GDB now understands the element 'tvar' in the XML traceframe info.
223 It has the id of the collected trace state variables.
225 * On S/390 targets that provide the transactional-execution feature,
226 the program interruption transaction diagnostic block (TDB) is now
227 represented as a number of additional "registers" in GDB.
233 The vCont packet supports a new 'r' action, that tells the remote
234 stub to step through an address range itself, without GDB
235 involvemement at each single-step.
237 qXfer:libraries-svr4:read's annex
238 The previously unused annex of the qXfer:libraries-svr4:read packet
239 is now used to support passing an argument list. The remote stub
240 reports support for this argument list to GDB's qSupported query.
241 The defined arguments are "start" and "prev", used to reduce work
242 necessary for library list updating, resulting in significant
245 * New features in the GDB remote stub, GDBserver
247 ** GDBserver now supports target-assisted range stepping. Currently
248 enabled on x86/x86_64 GNU/Linux targets.
250 ** GDBserver now adds element 'tvar' in the XML in the reply to
251 'qXfer:traceframe-info:read'. It has the id of the collected
252 trace state variables.
254 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
257 * New 'z' formatter for printing and examining memory, this displays the
258 value as hexadecimal zero padded on the left to the size of the type.
260 * GDB can now use Windows x64 unwinding data.
262 * The "set remotebaud" command has been replaced by "set serial baud".
263 Similarly, "show remotebaud" has been replaced by "show serial baud".
264 The "set remotebaud" and "show remotebaud" commands are still available
265 to provide backward compatibility with older versions of GDB.
267 *** Changes in GDB 7.6
269 * Target record has been renamed to record-full.
270 Record/replay is now enabled with the "record full" command.
271 This also affects settings that are associated with full record/replay
272 that have been moved from "set/show record" to "set/show record full":
274 set|show record full insn-number-max
275 set|show record full stop-at-limit
276 set|show record full memory-query
278 * A new record target "record-btrace" has been added. The new target
279 uses hardware support to record the control-flow of a process. It
280 does not support replaying the execution, but it implements the
281 below new commands for investigating the recorded execution log.
282 This new recording method can be enabled using:
286 The "record-btrace" target is only available on Intel Atom processors
287 and requires a Linux kernel 2.6.32 or later.
289 * Two new commands have been added for record/replay to give information
290 about the recorded execution without having to replay the execution.
291 The commands are only supported by "record btrace".
293 record instruction-history prints the execution history at
294 instruction granularity
296 record function-call-history prints the execution history at
299 * New native configurations
301 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
302 FreeBSD/powerpc powerpc*-*-freebsd
303 x86_64/Cygwin x86_64-*-cygwin*
304 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
308 ARM AArch64 aarch64*-*-elf
309 ARM AArch64 GNU/Linux aarch64*-*-linux
310 Lynx 178 PowerPC powerpc-*-lynx*178
311 x86_64/Cygwin x86_64-*-cygwin*
312 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
314 * If the configured location of system.gdbinit file (as given by the
315 --with-system-gdbinit option at configure time) is in the
316 data-directory (as specified by --with-gdb-datadir at configure
317 time) or in one of its subdirectories, then GDB will look for the
318 system-wide init file in the directory specified by the
319 --data-directory command-line option.
321 * New command line options:
323 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
324 other initialization files, unlike -nx which disables all of them.
326 * Removed command line options
328 -epoch This was used by the gdb mode in Epoch, an ancient fork of
331 * The 'ptype' and 'whatis' commands now accept an argument to control
334 * 'info proc' now works on some core files.
338 ** Vectors can be created with gdb.Type.vector.
340 ** Python's atexit.register now works in GDB.
342 ** Types can be pretty-printed via a Python API.
344 ** Python 3 is now supported (in addition to Python 2.4 or later)
346 ** New class gdb.Architecture exposes GDB's internal representation
347 of architecture in the Python API.
349 ** New method Frame.architecture returns the gdb.Architecture object
350 corresponding to the frame's architecture.
352 * New Python-based convenience functions:
354 ** $_memeq(buf1, buf2, length)
355 ** $_streq(str1, str2)
357 ** $_regex(str, regex)
359 * The 'cd' command now defaults to using '~' (the home directory) if not
362 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
363 default for GCC since November 2000.
365 * The command 'forward-search' can now be abbreviated as 'fo'.
367 * The command 'info tracepoints' can now display 'installed on target'
368 or 'not installed on target' for each non-pending location of tracepoint.
370 * New configure options
372 --enable-libmcheck/--disable-libmcheck
373 By default, development versions are built with -lmcheck on hosts
374 that support it, in order to help track memory corruption issues.
375 Release versions, on the other hand, are built without -lmcheck
376 by default. The --enable-libmcheck/--disable-libmcheck configure
377 options allow the user to override that default.
378 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
379 This configure option allows the user to build GDB with
380 libbabeltrace using which GDB can read Common Trace Format data.
382 * New commands (for set/show, see "New options" below)
385 Catch signals. This is similar to "handle", but allows commands and
386 conditions to be attached.
389 List the BFDs known to GDB.
391 python-interactive [command]
393 Start a Python interactive prompt, or evaluate the optional command
394 and print the result of expressions.
397 "py" is a new alias for "python".
399 enable type-printer [name]...
400 disable type-printer [name]...
401 Enable or disable type printers.
405 ** For the Renesas Super-H architecture, the "regs" command has been removed
406 (has been deprecated in GDB 7.5), and "info all-registers" should be used
411 set print type methods (on|off)
412 show print type methods
413 Control whether method declarations are displayed by "ptype".
414 The default is to show them.
416 set print type typedefs (on|off)
417 show print type typedefs
418 Control whether typedef definitions are displayed by "ptype".
419 The default is to show them.
421 set filename-display basename|relative|absolute
422 show filename-display
423 Control the way in which filenames is displayed.
424 The default is "relative", which preserves previous behavior.
426 set trace-buffer-size
427 show trace-buffer-size
428 Request target to change the size of trace buffer.
430 set remote trace-buffer-size-packet auto|on|off
431 show remote trace-buffer-size-packet
432 Control the use of the remote protocol `QTBuffer:size' packet.
436 Control display of debugging messages related to ARM AArch64.
439 set debug coff-pe-read
440 show debug coff-pe-read
441 Control display of debugging messages related to reading of COFF/PE
446 Control display of debugging messages related to Mach-O symbols
449 set debug notification
450 show debug notification
451 Control display of debugging info for async remote notification.
455 ** Command parameter changes are now notified using new async record
456 "=cmd-param-changed".
457 ** Trace frame changes caused by command "tfind" are now notified using
458 new async record "=traceframe-changed".
459 ** The creation, deletion and modification of trace state variables
460 are now notified using new async records "=tsv-created",
461 "=tsv-deleted" and "=tsv-modified".
462 ** The start and stop of process record are now notified using new
463 async record "=record-started" and "=record-stopped".
464 ** Memory changes are now notified using new async record
466 ** The data-disassemble command response will include a "fullname" field
467 containing the absolute file name when source has been requested.
468 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
469 command, to allow pattern filling of memory areas.
470 ** New commands "-catch-load"/"-catch-unload" added for intercepting
471 library load/unload events.
472 ** The response to breakpoint commands and breakpoint async records
473 includes an "installed" field containing a boolean state about each
474 non-pending tracepoint location is whether installed on target or not.
475 ** Output of the "-trace-status" command includes a "trace-file" field
476 containing the name of the trace file being examined. This field is
477 optional, and only present when examining a trace file.
478 ** The "fullname" field is now always present along with the "file" field,
479 even if the file cannot be found by GDB.
481 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
482 You must have the LZMA library available when configuring GDB for this
483 feature to be enabled. For more information, see:
484 http://fedoraproject.org/wiki/Features/MiniDebugInfo
489 Set the size of trace buffer. The remote stub reports support for this
490 packet to gdb's qSupported query.
493 Enable Branch Trace Store (BTS)-based branch tracing for the current
494 thread. The remote stub reports support for this packet to gdb's
498 Disable branch tracing for the current thread. The remote stub reports
499 support for this packet to gdb's qSupported query.
502 Read the traced branches for the current thread. The remote stub
503 reports support for this packet to gdb's qSupported query.
505 *** Changes in GDB 7.5
507 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
508 for more x32 ABI info.
510 * GDB now supports access to MIPS DSP registers on Linux targets.
512 * GDB now supports debugging microMIPS binaries.
514 * The "info os" command on GNU/Linux can now display information on
515 several new classes of objects managed by the operating system:
516 "info os procgroups" lists process groups
517 "info os files" lists file descriptors
518 "info os sockets" lists internet-domain sockets
519 "info os shm" lists shared-memory regions
520 "info os semaphores" lists semaphores
521 "info os msg" lists message queues
522 "info os modules" lists loaded kernel modules
524 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
525 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
526 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
527 options and inspect the probe arguments using the new $_probe_arg family
528 of convenience variables. You can obtain more information about SystemTap
529 in <http://sourceware.org/systemtap/>.
531 * GDB now supports reversible debugging on ARM, it allows you to
532 debug basic ARM and THUMB instructions, and provides
533 record/replay support.
535 * The option "symbol-reloading" has been deleted as it is no longer used.
539 ** GDB commands implemented in Python can now be put in command class
542 ** The "maint set python print-stack on|off" is now deleted.
544 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
545 apply "flag enum"-style pretty-printing to any enum.
547 ** gdb.lookup_symbol can now work when there is no current frame.
549 ** gdb.Symbol now has a 'line' attribute, holding the line number in
550 the source at which the symbol was defined.
552 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
553 method 'value'. The former indicates whether the symbol needs a
554 frame in order to compute its value, and the latter computes the
557 ** A new method 'referenced_value' on gdb.Value objects which can
558 dereference pointer as well as C++ reference values.
560 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
561 which return the global and static blocks (as gdb.Block objects),
562 of the underlying symbol table, respectively.
564 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
565 object associated with a PC value.
567 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
568 of the address range occupied by code for the current source line.
570 * Go language support.
571 GDB now supports debugging programs written in the Go programming
574 * GDBserver now supports stdio connections.
575 E.g. (gdb) target remote | ssh myhost gdbserver - hello
577 * The binary "gdbtui" can no longer be built or installed.
578 Use "gdb -tui" instead.
580 * GDB will now print "flag" enums specially. A flag enum is one where
581 all the enumerator values have no bits in common when pairwise
582 "and"ed. When printing a value whose type is a flag enum, GDB will
583 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
584 (gdb) print (enum E) 3
587 * The filename part of a linespec will now match trailing components
588 of a source file name. For example, "break gcc/expr.c:1000" will
589 now set a breakpoint in build/gcc/expr.c, but not
592 * The "info proc" and "generate-core-file" commands will now also
593 work on remote targets connected to GDBserver on Linux.
595 * The command "info catch" has been removed. It has been disabled
598 * The "catch exception" and "catch assert" commands now accept
599 a condition at the end of the command, much like the "break"
600 command does. For instance:
602 (gdb) catch exception Constraint_Error if Barrier = True
604 Previously, it was possible to add a condition to such catchpoints,
605 but it had to be done as a second step, after the catchpoint had been
606 created, using the "condition" command.
608 * The "info static-tracepoint-marker" command will now also work on
609 native Linux targets with in-process agent.
611 * GDB can now set breakpoints on inlined functions.
613 * The .gdb_index section has been updated to include symbols for
614 inlined functions. GDB will ignore older .gdb_index sections by
615 default, which could cause symbol files to be loaded more slowly
616 until their .gdb_index sections can be recreated. The new command
617 "set use-deprecated-index-sections on" will cause GDB to use any older
618 .gdb_index sections it finds. This will restore performance, but the
619 ability to set breakpoints on inlined functions will be lost in symbol
620 files with older .gdb_index sections.
622 The .gdb_index section has also been updated to record more information
623 about each symbol. This speeds up the "info variables", "info functions"
624 and "info types" commands when used with programs having the .gdb_index
625 section, as well as speeding up debugging with shared libraries using
626 the .gdb_index section.
628 * Ada support for GDB/MI Variable Objects has been added.
630 * GDB can now support 'breakpoint always-inserted mode' in 'record'
635 ** New command -info-os is the MI equivalent of "info os".
637 ** Output logs ("set logging" and related) now include MI output.
641 ** "set use-deprecated-index-sections on|off"
642 "show use-deprecated-index-sections on|off"
643 Controls the use of deprecated .gdb_index sections.
645 ** "catch load" and "catch unload" can be used to stop when a shared
646 library is loaded or unloaded, respectively.
648 ** "enable count" can be used to auto-disable a breakpoint after
651 ** "info vtbl" can be used to show the virtual method tables for
652 C++ and Java objects.
654 ** "explore" and its sub commands "explore value" and "explore type"
655 can be used to recursively explore values and types of
656 expressions. These commands are available only if GDB is
657 configured with '--with-python'.
659 ** "info auto-load" shows status of all kinds of auto-loaded files,
660 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
661 sequences of commands files, "info auto-load python-scripts"
662 shows status of auto-loading Python script files,
663 "info auto-load local-gdbinit" shows status of loading init file
664 (.gdbinit) from current directory and "info auto-load libthread-db" shows
665 status of inferior specific thread debugging shared library loading.
667 ** "info auto-load-scripts", "set auto-load-scripts on|off"
668 and "show auto-load-scripts" commands have been deprecated, use their
669 "info auto-load python-scripts", "set auto-load python-scripts on|off"
670 and "show auto-load python-scripts" counterparts instead.
672 ** "dprintf location,format,args..." creates a dynamic printf, which
673 is basically a breakpoint that does a printf and immediately
674 resumes your program's execution, so it is like a printf that you
675 can insert dynamically at runtime instead of at compiletime.
677 ** "set print symbol"
679 Controls whether GDB attempts to display the symbol, if any,
680 corresponding to addresses it prints. This defaults to "on", but
681 you can set it to "off" to restore GDB's previous behavior.
683 * Deprecated commands
685 ** For the Renesas Super-H architecture, the "regs" command has been
686 deprecated, and "info all-registers" should be used instead.
690 Renesas RL78 rl78-*-elf
691 HP OpenVMS ia64 ia64-hp-openvms*
693 * GDBserver supports evaluation of breakpoint conditions. When
694 support is advertised by GDBserver, GDB may be told to send the
695 breakpoint conditions in bytecode form to GDBserver. GDBserver
696 will only report the breakpoint trigger to GDB when its condition
702 show mips compression
703 Select the compressed ISA encoding used in functions that have no symbol
704 information available. The encoding can be set to either of:
707 and is updated automatically from ELF file flags if available.
709 set breakpoint condition-evaluation
710 show breakpoint condition-evaluation
711 Control whether breakpoint conditions are evaluated by GDB ("host") or by
712 GDBserver ("target"). Default option "auto" chooses the most efficient
714 This option can improve debugger efficiency depending on the speed of the
718 Disable auto-loading globally.
721 Show auto-loading setting of all kinds of auto-loaded files.
723 set auto-load gdb-scripts on|off
724 show auto-load gdb-scripts
725 Control auto-loading of GDB canned sequences of commands files.
727 set auto-load python-scripts on|off
728 show auto-load python-scripts
729 Control auto-loading of Python script files.
731 set auto-load local-gdbinit on|off
732 show auto-load local-gdbinit
733 Control loading of init file (.gdbinit) from current directory.
735 set auto-load libthread-db on|off
736 show auto-load libthread-db
737 Control auto-loading of inferior specific thread debugging shared library.
739 set auto-load scripts-directory <dir1>[:<dir2>...]
740 show auto-load scripts-directory
741 Set a list of directories from which to load auto-loaded scripts.
742 Automatically loaded Python scripts and GDB scripts are located in one
743 of the directories listed by this option.
744 The delimiter (':' above) may differ according to the host platform.
746 set auto-load safe-path <dir1>[:<dir2>...]
747 show auto-load safe-path
748 Set a list of directories from which it is safe to auto-load files.
749 The delimiter (':' above) may differ according to the host platform.
751 set debug auto-load on|off
753 Control display of debugging info for auto-loading the files above.
755 set dprintf-style gdb|call|agent
757 Control the way in which a dynamic printf is performed; "gdb"
758 requests a GDB printf command, while "call" causes dprintf to call a
759 function in the inferior. "agent" requests that the target agent
760 (such as GDBserver) do the printing.
762 set dprintf-function <expr>
763 show dprintf-function
764 set dprintf-channel <expr>
766 Set the function and optional first argument to the call when using
767 the "call" style of dynamic printf.
769 set disconnected-dprintf on|off
770 show disconnected-dprintf
771 Control whether agent-style dynamic printfs continue to be in effect
772 after GDB disconnects.
774 * New configure options
777 Configure default value for the 'set auto-load scripts-directory'
778 setting above. It defaults to '$debugdir:$datadir/auto-load',
779 $debugdir representing global debugging info directories (available
780 via 'show debug-file-directory') and $datadir representing GDB's data
781 directory (available via 'show data-directory').
783 --with-auto-load-safe-path
784 Configure default value for the 'set auto-load safe-path' setting
785 above. It defaults to the --with-auto-load-dir setting.
787 --without-auto-load-safe-path
788 Set 'set auto-load safe-path' to '/', effectively disabling this
793 z0/z1 conditional breakpoints extension
795 The z0/z1 breakpoint insertion packets have been extended to carry
796 a list of conditional expressions over to the remote stub depending on the
797 condition evaluation mode. The use of this extension can be controlled
798 via the "set remote conditional-breakpoints-packet" command.
802 Specify the signals which the remote stub may pass to the debugged
803 program without GDB involvement.
805 * New command line options
807 --init-command=FILE, -ix Like --command, -x but execute it
808 before loading inferior.
809 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
810 execute it before loading inferior.
812 *** Changes in GDB 7.4
814 * GDB now handles ambiguous linespecs more consistently; the existing
815 FILE:LINE support has been expanded to other types of linespecs. A
816 breakpoint will now be set on all matching locations in all
817 inferiors, and locations will be added or removed according to
820 * GDB now allows you to skip uninteresting functions and files when
821 stepping with the "skip function" and "skip file" commands.
823 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
824 and "show remote hardware-watchpoint-length-limit". These allows to
825 set or show the maximum length limit (in bytes) of a remote
826 target hardware watchpoint.
828 This allows e.g. to use "unlimited" hardware watchpoints with the
829 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
830 watchpoints are slower than real hardware watchpoints but are
831 significantly faster than gdb software watchpoints.
835 ** The register_pretty_printer function in module gdb.printing now takes
836 an optional `replace' argument. If True, the new printer replaces any
839 ** The "maint set python print-stack on|off" command has been
840 deprecated and will be deleted in GDB 7.5.
841 A new command: "set python print-stack none|full|message" has
842 replaced it. Additionally, the default for "print-stack" is
843 now "message", which just prints the error message without
846 ** A prompt substitution hook (prompt_hook) is now available to the
849 ** A new Python module, gdb.prompt has been added to the GDB Python
850 modules library. This module provides functionality for
851 escape sequences in prompts (used by set/show
852 extended-prompt). These escape sequences are replaced by their
855 ** Python commands and convenience-functions located in
856 'data-directory'/python/gdb/command and
857 'data-directory'/python/gdb/function are now automatically loaded
860 ** Blocks now provide four new attributes. global_block and
861 static_block will return the global and static blocks
862 respectively. is_static and is_global are boolean attributes
863 that indicate if the block is one of those two types.
865 ** Symbols now provide the "type" attribute, the type of the symbol.
867 ** The "gdb.breakpoint" function has been deprecated in favor of
870 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
871 of a function. This class is based on the "finish" command
872 available in the CLI.
874 ** Type objects for struct and union types now allow access to
875 the fields using standard Python dictionary (mapping) methods.
876 For example, "some_type['myfield']" now works, as does
879 ** A new event "gdb.new_objfile" has been added, triggered by loading a
882 ** A new function, "deep_items" has been added to the gdb.types
883 module in the GDB Python modules library. This function returns
884 an iterator over the fields of a struct or union type. Unlike
885 the standard Python "iteritems" method, it will recursively traverse
886 any anonymous fields.
890 ** "*stopped" events can report several new "reason"s, such as
893 ** Breakpoint changes are now notified using new async records, like
894 "=breakpoint-modified".
896 ** New command -ada-task-info.
898 * libthread-db-search-path now supports two special values: $sdir and $pdir.
899 $sdir specifies the default system locations of shared libraries.
900 $pdir specifies the directory where the libpthread used by the application
903 GDB no longer looks in $sdir and $pdir after it has searched the directories
904 mentioned in libthread-db-search-path. If you want to search those
905 directories, they must be specified in libthread-db-search-path.
906 The default value of libthread-db-search-path on GNU/Linux and Solaris
907 systems is now "$sdir:$pdir".
909 $pdir is not supported by gdbserver, it is currently ignored.
910 $sdir is supported by gdbserver.
912 * New configure option --with-iconv-bin.
913 When using the internationalization support like the one in the GNU C
914 library, GDB will invoke the "iconv" program to get a list of supported
915 character sets. If this program lives in a non-standard location, one can
916 use this option to specify where to find it.
918 * When natively debugging programs on PowerPC BookE processors running
919 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
920 watchpoints, which specify a mask in addition to an address to watch.
921 The mask specifies that some bits of an address (the bits which are
922 reset in the mask) should be ignored when matching the address accessed
923 by the inferior against the watchpoint address. See the "PowerPC Embedded"
924 section in the user manual for more details.
926 * The new option --once causes GDBserver to stop listening for connections once
927 the first connection is made. The listening port used by GDBserver will
928 become available after that.
930 * New commands "info macros" and "alias" have been added.
932 * New function parameters suffix @entry specifies value of function parameter
933 at the time the function got called. Entry values are available only since
939 "!" is now an alias of the "shell" command.
940 Note that no space is needed between "!" and SHELL COMMAND.
944 watch EXPRESSION mask MASK_VALUE
945 The watch command now supports the mask argument which allows creation
946 of masked watchpoints, if the current architecture supports this feature.
948 info auto-load-scripts [REGEXP]
949 This command was formerly named "maintenance print section-scripts".
950 It is now generally useful and is no longer a maintenance-only command.
952 info macro [-all] [--] MACRO
953 The info macro command has new options `-all' and `--'. The first for
954 printing all definitions of a macro. The second for explicitly specifying
955 the end of arguments and the beginning of the macro name in case the macro
956 name starts with a hyphen.
958 collect[/s] EXPRESSIONS
959 The tracepoint collect command now takes an optional modifier "/s"
960 that directs it to dereference pointer-to-character types and
961 collect the bytes of memory up to a zero byte. The behavior is
962 similar to what you see when you use the regular print command on a
963 string. An optional integer following the "/s" sets a bound on the
964 number of bytes that will be collected.
967 The trace start command now interprets any supplied arguments as a
968 note to be recorded with the trace run, with an effect similar to
969 setting the variable trace-notes.
972 The trace stop command now interprets any arguments as a note to be
973 mentioned along with the tstatus report that the trace was stopped
974 with a command. The effect is similar to setting the variable
977 * Tracepoints can now be enabled and disabled at any time after a trace
978 experiment has been started using the standard "enable" and "disable"
979 commands. It is now possible to start a trace experiment with no enabled
980 tracepoints; GDB will display a warning, but will allow the experiment to
981 begin, assuming that tracepoints will be enabled as needed while the trace
984 * Fast tracepoints on 32-bit x86-architectures can now be placed at
985 locations with 4-byte instructions, when they were previously
986 limited to locations with instructions of 5 bytes or longer.
990 set debug dwarf2-read
991 show debug dwarf2-read
992 Turns on or off display of debugging messages related to reading
993 DWARF debug info. The default is off.
995 set debug symtab-create
996 show debug symtab-create
997 Turns on or off display of debugging messages related to symbol table
998 creation. The default is off.
1001 show extended-prompt
1002 Set the GDB prompt, and allow escape sequences to be inserted to
1003 display miscellaneous information (see 'help set extended-prompt'
1004 for the list of sequences). This prompt (and any information
1005 accessed through the escape sequences) is updated every time the
1006 prompt is displayed.
1008 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1009 show print entry-values
1010 Set printing of frame argument values at function entry. In some cases
1011 GDB can determine the value of function argument which was passed by the
1012 function caller, even if the value was modified inside the called function.
1014 set debug entry-values
1015 show debug entry-values
1016 Control display of debugging info for determining frame argument values at
1017 function entry and virtual tail call frames.
1019 set basenames-may-differ
1020 show basenames-may-differ
1021 Set whether a source file may have multiple base names.
1022 (A "base name" is the name of a file with the directory part removed.
1023 Example: The base name of "/home/user/hello.c" is "hello.c".)
1024 If set, GDB will canonicalize file names (e.g., expand symlinks)
1025 before comparing them. Canonicalization is an expensive operation,
1026 but it allows the same file be known by more than one base name.
1027 If not set (the default), all source files are assumed to have just
1028 one base name, and gdb will do file name comparisons more efficiently.
1034 Set a user name and notes for the current and any future trace runs.
1035 This is useful for long-running and/or disconnected traces, to
1036 inform others (or yourself) as to who is running the trace, supply
1037 contact information, or otherwise explain what is going on.
1039 set trace-stop-notes
1040 show trace-stop-notes
1041 Set a note attached to the trace run, that is displayed when the
1042 trace has been stopped by a tstop command. This is useful for
1043 instance as an explanation, if you are stopping a trace run that was
1044 started by someone else.
1046 * New remote packets
1050 Dynamically enable a tracepoint in a started trace experiment.
1054 Dynamically disable a tracepoint in a started trace experiment.
1058 Set the user and notes of the trace run.
1062 Query the current status of a tracepoint.
1066 Query the minimum length of instruction at which a fast tracepoint may
1069 * Dcache size (number of lines) and line-size are now runtime-configurable
1070 via "set dcache line" and "set dcache line-size" commands.
1074 Texas Instruments TMS320C6x tic6x-*-*
1078 Renesas RL78 rl78-*-elf
1080 *** Changes in GDB 7.3.1
1082 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1084 *** Changes in GDB 7.3
1086 * GDB has a new command: "thread find [REGEXP]".
1087 It finds the thread id whose name, target id, or thread extra info
1088 matches the given regular expression.
1090 * The "catch syscall" command now works on mips*-linux* targets.
1092 * The -data-disassemble MI command now supports modes 2 and 3 for
1093 dumping the instruction opcodes.
1095 * New command line options
1097 -data-directory DIR Specify DIR as the "data-directory".
1098 This is mostly for testing purposes.
1100 * The "maint set python auto-load on|off" command has been renamed to
1101 "set auto-load-scripts on|off".
1103 * GDB has a new command: "set directories".
1104 It is like the "dir" command except that it replaces the
1105 source path list instead of augmenting it.
1107 * GDB now understands thread names.
1109 On GNU/Linux, "info threads" will display the thread name as set by
1110 prctl or pthread_setname_np.
1112 There is also a new command, "thread name", which can be used to
1113 assign a name internally for GDB to display.
1116 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1117 has been integrated into GDB.
1121 ** The function gdb.Write now accepts an optional keyword 'stream'.
1122 This keyword, when provided, will direct the output to either
1123 stdout, stderr, or GDB's logging output.
1125 ** Parameters can now be be sub-classed in Python, and in particular
1126 you may implement the get_set_doc and get_show_doc functions.
1127 This improves how Parameter set/show documentation is processed
1128 and allows for more dynamic content.
1130 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1131 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1132 have an is_valid method.
1134 ** Breakpoints can now be sub-classed in Python, and in particular
1135 you may implement a 'stop' function that is executed each time
1136 the inferior reaches that breakpoint.
1138 ** New function gdb.lookup_global_symbol looks up a global symbol.
1140 ** GDB values in Python are now callable if the value represents a
1141 function. For example, if 'some_value' represents a function that
1142 takes two integer parameters and returns a value, you can call
1143 that function like so:
1145 result = some_value (10,20)
1147 ** Module gdb.types has been added.
1148 It contains a collection of utilities for working with gdb.Types objects:
1149 get_basic_type, has_field, make_enum_dict.
1151 ** Module gdb.printing has been added.
1152 It contains utilities for writing and registering pretty-printers.
1153 New classes: PrettyPrinter, SubPrettyPrinter,
1154 RegexpCollectionPrettyPrinter.
1155 New function: register_pretty_printer.
1157 ** New commands "info pretty-printers", "enable pretty-printer" and
1158 "disable pretty-printer" have been added.
1160 ** gdb.parameter("directories") is now available.
1162 ** New function gdb.newest_frame returns the newest frame in the
1165 ** The gdb.InferiorThread class has a new "name" attribute. This
1166 holds the thread's name.
1168 ** Python Support for Inferior events.
1169 Python scripts can add observers to be notified of events
1170 occurring in the process being debugged.
1171 The following events are currently supported:
1172 - gdb.events.cont Continue event.
1173 - gdb.events.exited Inferior exited event.
1174 - gdb.events.stop Signal received, and Breakpoint hit events.
1178 ** GDB now puts template parameters in scope when debugging in an
1179 instantiation. For example, if you have:
1181 template<int X> int func (void) { return X; }
1183 then if you step into func<5>, "print X" will show "5". This
1184 feature requires proper debuginfo support from the compiler; it
1185 was added to GCC 4.5.
1187 ** The motion commands "next", "finish", "until", and "advance" now
1188 work better when exceptions are thrown. In particular, GDB will
1189 no longer lose control of the inferior; instead, the GDB will
1190 stop the inferior at the point at which the exception is caught.
1191 This functionality requires a change in the exception handling
1192 code that was introduced in GCC 4.5.
1194 * GDB now follows GCC's rules on accessing volatile objects when
1195 reading or writing target state during expression evaluation.
1196 One notable difference to prior behavior is that "print x = 0"
1197 no longer generates a read of x; the value of the assignment is
1198 now always taken directly from the value being assigned.
1200 * GDB now has some support for using labels in the program's source in
1201 linespecs. For instance, you can use "advance label" to continue
1202 execution to a label.
1204 * GDB now has support for reading and writing a new .gdb_index
1205 section. This section holds a fast index of DWARF debugging
1206 information and can be used to greatly speed up GDB startup and
1207 operation. See the documentation for `save gdb-index' for details.
1209 * The "watch" command now accepts an optional "-location" argument.
1210 When used, this causes GDB to watch the memory referred to by the
1211 expression. Such a watchpoint is never deleted due to it going out
1214 * GDB now supports thread debugging of core dumps on GNU/Linux.
1216 GDB now activates thread debugging using the libthread_db library
1217 when debugging GNU/Linux core dumps, similarly to when debugging
1218 live processes. As a result, when debugging a core dump file, GDB
1219 is now able to display pthread_t ids of threads. For example, "info
1220 threads" shows the same output as when debugging the process when it
1221 was live. In earlier releases, you'd see something like this:
1224 * 1 LWP 6780 main () at main.c:10
1226 While now you see this:
1229 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1231 It is also now possible to inspect TLS variables when debugging core
1234 When debugging a core dump generated on a machine other than the one
1235 used to run GDB, you may need to point GDB at the correct
1236 libthread_db library with the "set libthread-db-search-path"
1237 command. See the user manual for more details on this command.
1239 * When natively debugging programs on PowerPC BookE processors running
1240 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1241 which stop execution of the inferior whenever it executes an instruction
1242 at any address within the specified range. See the "PowerPC Embedded"
1243 section in the user manual for more details.
1245 * New features in the GDB remote stub, GDBserver
1247 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1248 and i686 LynxOS (version 5.x).
1250 ** GDBserver is now supported on Blackfin Linux.
1252 * New native configurations
1254 ia64 HP-UX ia64-*-hpux*
1258 Analog Devices, Inc. Blackfin Processor bfin-*
1260 * Ada task switching is now supported on sparc-elf targets when
1261 debugging a program using the Ravenscar Profile. For more information,
1262 see the "Tasking Support when using the Ravenscar Profile" section
1263 in the GDB user manual.
1265 * Guile support was removed.
1267 * New features in the GNU simulator
1269 ** The --map-info flag lists all known core mappings.
1271 ** CFI flashes may be simulated via the "cfi" device.
1273 *** Changes in GDB 7.2
1275 * Shared library support for remote targets by default
1277 When GDB is configured for a generic, non-OS specific target, like
1278 for example, --target=arm-eabi or one of the many *-*-elf targets,
1279 GDB now queries remote stubs for loaded shared libraries using the
1280 `qXfer:libraries:read' packet. Previously, shared library support
1281 was always disabled for such configurations.
1285 ** Argument Dependent Lookup (ADL)
1287 In C++ ADL lookup directs function search to the namespaces of its
1288 arguments even if the namespace has not been imported.
1298 Here the compiler will search for `foo' in the namespace of 'b'
1299 and find A::foo. GDB now supports this. This construct is commonly
1300 used in the Standard Template Library for operators.
1302 ** Improved User Defined Operator Support
1304 In addition to member operators, GDB now supports lookup of operators
1305 defined in a namespace and imported with a `using' directive, operators
1306 defined in the global scope, operators imported implicitly from an
1307 anonymous namespace, and the ADL operators mentioned in the previous
1309 GDB now also supports proper overload resolution for all the previously
1310 mentioned flavors of operators.
1312 ** static const class members
1314 Printing of static const class members that are initialized in the
1315 class definition has been fixed.
1317 * Windows Thread Information Block access.
1319 On Windows targets, GDB now supports displaying the Windows Thread
1320 Information Block (TIB) structure. This structure is visible either
1321 by using the new command `info w32 thread-information-block' or, by
1322 dereferencing the new convenience variable named `$_tlb', a
1323 thread-specific pointer to the TIB. This feature is also supported
1324 when remote debugging using GDBserver.
1326 * Static tracepoints
1328 Static tracepoints are calls in the user program into a tracing
1329 library. One such library is a port of the LTTng kernel tracer to
1330 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1331 When debugging with GDBserver, GDB now supports combining the GDB
1332 tracepoint machinery with such libraries. For example: the user can
1333 use GDB to probe a static tracepoint marker (a call from the user
1334 program into the tracing library) with the new "strace" command (see
1335 "New commands" below). This creates a "static tracepoint" in the
1336 breakpoint list, that can be manipulated with the same feature set
1337 as fast and regular tracepoints. E.g., collect registers, local and
1338 global variables, collect trace state variables, and define
1339 tracepoint conditions. In addition, the user can collect extra
1340 static tracepoint marker specific data, by collecting the new
1341 $_sdata internal variable. When analyzing the trace buffer, you can
1342 inspect $_sdata like any other variable available to GDB. For more
1343 information, see the "Tracepoints" chapter in GDB user manual. New
1344 remote packets have been defined to support static tracepoints, see
1345 the "New remote packets" section below.
1347 * Better reconstruction of tracepoints after disconnected tracing
1349 GDB will attempt to download the original source form of tracepoint
1350 definitions when starting a trace run, and then will upload these
1351 upon reconnection to the target, resulting in a more accurate
1352 reconstruction of the tracepoints that are in use on the target.
1356 You can now exercise direct control over the ways that GDB can
1357 affect your program. For instance, you can disallow the setting of
1358 breakpoints, so that the program can run continuously (assuming
1359 non-stop mode). In addition, the "observer" variable is available
1360 to switch all of the different controls; in observer mode, GDB
1361 cannot affect the target's behavior at all, which is useful for
1362 tasks like diagnosing live systems in the field.
1364 * The new convenience variable $_thread holds the number of the
1367 * New remote packets
1371 Return the address of the Windows Thread Information Block of a given thread.
1375 In response to several of the tracepoint packets, the target may now
1376 also respond with a number of intermediate `qRelocInsn' request
1377 packets before the final result packet, to have GDB handle
1378 relocating an instruction to execute at a different address. This
1379 is particularly useful for stubs that support fast tracepoints. GDB
1380 reports support for this feature in the qSupported packet.
1384 List static tracepoint markers in the target program.
1388 List static tracepoint markers at a given address in the target
1391 qXfer:statictrace:read
1393 Read the static trace data collected (by a `collect $_sdata'
1394 tracepoint action). The remote stub reports support for this packet
1395 to gdb's qSupported query.
1399 Send the current settings of GDB's permission flags.
1403 Send part of the source (textual) form of a tracepoint definition,
1404 which includes location, conditional, and action list.
1406 * The source command now accepts a -s option to force searching for the
1407 script in the source search path even if the script name specifies
1410 * New features in the GDB remote stub, GDBserver
1412 - GDBserver now support tracepoints (including fast tracepoints, and
1413 static tracepoints). The feature is currently supported by the
1414 i386-linux and amd64-linux builds. See the "Tracepoints support
1415 in gdbserver" section in the manual for more information.
1417 GDBserver JIT compiles the tracepoint's conditional agent
1418 expression bytecode into native code whenever possible for low
1419 overhead dynamic tracepoints conditionals. For such tracepoints,
1420 an expression that examines program state is evaluated when the
1421 tracepoint is reached, in order to determine whether to capture
1422 trace data. If the condition is simple and false, processing the
1423 tracepoint finishes very quickly and no data is gathered.
1425 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1426 for static tracepoints support.
1428 - GDBserver now supports x86_64 Windows 64-bit debugging.
1430 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1431 it understands register description.
1433 * The --batch flag now disables pagination and queries.
1435 * X86 general purpose registers
1437 GDB now supports reading/writing byte, word and double-word x86
1438 general purpose registers directly. This means you can use, say,
1439 $ah or $ax to refer, respectively, to the byte register AH and
1440 16-bit word register AX that are actually portions of the 32-bit
1441 register EAX or 64-bit register RAX.
1443 * The `commands' command now accepts a range of breakpoints to modify.
1444 A plain `commands' following a command that creates multiple
1445 breakpoints affects all the breakpoints set by that command. This
1446 applies to breakpoints set by `rbreak', and also applies when a
1447 single `break' command creates multiple breakpoints (e.g.,
1448 breakpoints on overloaded c++ functions).
1450 * The `rbreak' command now accepts a filename specification as part of
1451 its argument, limiting the functions selected by the regex to those
1452 in the specified file.
1454 * Support for remote debugging Windows and SymbianOS shared libraries
1455 from Unix hosts has been improved. Non Windows GDB builds now can
1456 understand target reported file names that follow MS-DOS based file
1457 system semantics, such as file names that include drive letters and
1458 use the backslash character as directory separator. This makes it
1459 possible to transparently use the "set sysroot" and "set
1460 solib-search-path" on Unix hosts to point as host copies of the
1461 target's shared libraries. See the new command "set
1462 target-file-system-kind" described below, and the "Commands to
1463 specify files" section in the user manual for more information.
1467 eval template, expressions...
1468 Convert the values of one or more expressions under the control
1469 of the string template to a command line, and call it.
1471 set target-file-system-kind unix|dos-based|auto
1472 show target-file-system-kind
1473 Set or show the assumed file system kind for target reported file
1476 save breakpoints <filename>
1477 Save all current breakpoint definitions to a file suitable for use
1478 in a later debugging session. To read the saved breakpoint
1479 definitions, use the `source' command.
1481 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1484 info static-tracepoint-markers
1485 Display information about static tracepoint markers in the target.
1487 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1488 Define a static tracepoint by probing a marker at the given
1489 function, line, address, or marker ID.
1493 Enable and disable observer mode.
1495 set may-write-registers on|off
1496 set may-write-memory on|off
1497 set may-insert-breakpoints on|off
1498 set may-insert-tracepoints on|off
1499 set may-insert-fast-tracepoints on|off
1500 set may-interrupt on|off
1501 Set individual permissions for GDB effects on the target. Note that
1502 some of these settings can have undesirable or surprising
1503 consequences, particularly when changed in the middle of a session.
1504 For instance, disabling the writing of memory can prevent
1505 breakpoints from being inserted, cause single-stepping to fail, or
1506 even crash your program, if you disable after breakpoints have been
1507 inserted. However, GDB should not crash.
1509 set record memory-query on|off
1510 show record memory-query
1511 Control whether to stop the inferior if memory changes caused
1512 by an instruction cannot be recorded.
1517 The disassemble command now supports "start,+length" form of two arguments.
1521 ** GDB now provides a new directory location, called the python directory,
1522 where Python scripts written for GDB can be installed. The location
1523 of that directory is <data-directory>/python, where <data-directory>
1524 is the GDB data directory. For more details, see section `Scripting
1525 GDB using Python' in the manual.
1527 ** The GDB Python API now has access to breakpoints, symbols, symbol
1528 tables, program spaces, inferiors, threads and frame's code blocks.
1529 Additionally, GDB Parameters can now be created from the API, and
1530 manipulated via set/show in the CLI.
1532 ** New functions gdb.target_charset, gdb.target_wide_charset,
1533 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1535 ** New exception gdb.GdbError.
1537 ** Pretty-printers are now also looked up in the current program space.
1539 ** Pretty-printers can now be individually enabled and disabled.
1541 ** GDB now looks for names of Python scripts to auto-load in a
1542 special section named `.debug_gdb_scripts', in addition to looking
1543 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1545 * Tracepoint actions were unified with breakpoint commands. In particular,
1546 there are no longer differences in "info break" output for breakpoints and
1547 tracepoints and the "commands" command can be used for both tracepoints and
1548 regular breakpoints.
1552 ARM Symbian arm*-*-symbianelf*
1554 * D language support.
1555 GDB now supports debugging programs written in the D programming
1558 * GDB now supports the extended ptrace interface for PowerPC which is
1559 available since Linux kernel version 2.6.34. This automatically enables
1560 any hardware breakpoints and additional hardware watchpoints available in
1561 the processor. The old ptrace interface exposes just one hardware
1562 watchpoint and no hardware breakpoints.
1564 * GDB is now able to use the Data Value Compare (DVC) register available on
1565 embedded PowerPC processors to implement in hardware simple watchpoint
1566 conditions of the form:
1568 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1570 This works in native GDB running on Linux kernels with the extended ptrace
1571 interface mentioned above.
1573 *** Changes in GDB 7.1
1577 ** Namespace Support
1579 GDB now supports importing of namespaces in C++. This enables the
1580 user to inspect variables from imported namespaces. Support for
1581 namepace aliasing has also been added. So, if a namespace is
1582 aliased in the current scope (e.g. namepace C=A; ) the user can
1583 print variables using the alias (e.g. (gdb) print C::x).
1587 All known bugs relating to the printing of virtual base class were
1588 fixed. It is now possible to call overloaded static methods using a
1593 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1594 and reinterpret_cast<> are now handled by the C++ expression parser.
1598 Xilinx MicroBlaze microblaze-*-*
1603 Xilinx MicroBlaze microblaze
1606 * Multi-program debugging.
1608 GDB now has support for multi-program (a.k.a. multi-executable or
1609 multi-exec) debugging. This allows for debugging multiple inferiors
1610 simultaneously each running a different program under the same GDB
1611 session. See "Debugging Multiple Inferiors and Programs" in the
1612 manual for more information. This implied some user visible changes
1613 in the multi-inferior support. For example, "info inferiors" now
1614 lists inferiors that are not running yet or that have exited
1615 already. See also "New commands" and "New options" below.
1617 * New tracing features
1619 GDB's tracepoint facility now includes several new features:
1621 ** Trace state variables
1623 GDB tracepoints now include support for trace state variables, which
1624 are variables managed by the target agent during a tracing
1625 experiment. They are useful for tracepoints that trigger each
1626 other, so for instance one tracepoint can count hits in a variable,
1627 and then a second tracepoint has a condition that is true when the
1628 count reaches a particular value. Trace state variables share the
1629 $-syntax of GDB convenience variables, and can appear in both
1630 tracepoint actions and condition expressions. Use the "tvariable"
1631 command to create, and "info tvariables" to view; see "Trace State
1632 Variables" in the manual for more detail.
1636 GDB now includes an option for defining fast tracepoints, which
1637 targets may implement more efficiently, such as by installing a jump
1638 into the target agent rather than a trap instruction. The resulting
1639 speedup can be by two orders of magnitude or more, although the
1640 tradeoff is that some program locations on some target architectures
1641 might not allow fast tracepoint installation, for instance if the
1642 instruction to be replaced is shorter than the jump. To request a
1643 fast tracepoint, use the "ftrace" command, with syntax identical to
1644 the regular trace command.
1646 ** Disconnected tracing
1648 It is now possible to detach GDB from the target while it is running
1649 a trace experiment, then reconnect later to see how the experiment
1650 is going. In addition, a new variable disconnected-tracing lets you
1651 tell the target agent whether to continue running a trace if the
1652 connection is lost unexpectedly.
1656 GDB now has the ability to save the trace buffer into a file, and
1657 then use that file as a target, similarly to you can do with
1658 corefiles. You can select trace frames, print data that was
1659 collected in them, and use tstatus to display the state of the
1660 tracing run at the moment that it was saved. To create a trace
1661 file, use "tsave <filename>", and to use it, do "target tfile
1664 ** Circular trace buffer
1666 You can ask the target agent to handle the trace buffer as a
1667 circular buffer, discarding the oldest trace frames to make room for
1668 newer ones, by setting circular-trace-buffer to on. This feature may
1669 not be available for all target agents.
1674 The disassemble command, when invoked with two arguments, now requires
1675 the arguments to be comma-separated.
1678 The info variables command now displays variable definitions. Files
1679 which only declare a variable are not shown.
1682 The source command is now capable of sourcing Python scripts.
1683 This feature is dependent on the debugger being build with Python
1686 Related to this enhancement is also the introduction of a new command
1687 "set script-extension" (see below).
1689 * New commands (for set/show, see "New options" below)
1691 record save [<FILENAME>]
1692 Save a file (in core file format) containing the process record
1693 execution log for replay debugging at a later time.
1695 record restore <FILENAME>
1696 Restore the process record execution log that was saved at an
1697 earlier time, for replay debugging.
1699 add-inferior [-copies <N>] [-exec <FILENAME>]
1702 clone-inferior [-copies <N>] [ID]
1703 Make a new inferior ready to execute the same program another
1704 inferior has loaded.
1709 maint info program-spaces
1710 List the program spaces loaded into GDB.
1712 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1713 show remote interrupt-sequence
1714 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1715 as the sequence to the remote target in order to interrupt the execution.
1716 Ctrl-C is a default. Some system prefers BREAK which is high level of
1717 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1718 Magic SysRq g. It is BREAK signal and character 'g'.
1720 set remote interrupt-on-connect [on | off]
1721 show remote interrupt-on-connect
1722 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1723 remote target when gdb connects to it. This is needed when you debug
1726 set remotebreak [on | off]
1728 Deprecated. Use "set/show remote interrupt-sequence" instead.
1730 tvariable $NAME [ = EXP ]
1731 Create or modify a trace state variable.
1734 List trace state variables and their values.
1736 delete tvariable $NAME ...
1737 Delete one or more trace state variables.
1740 Evaluate the given expressions without collecting anything into the
1741 trace buffer. (Valid in tracepoint actions only.)
1743 ftrace FN / FILE:LINE / *ADDR
1744 Define a fast tracepoint at the given function, line, or address.
1746 * New expression syntax
1748 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1749 GDB now parses 0b101010 identically with 42.
1753 set follow-exec-mode new|same
1754 show follow-exec-mode
1755 Control whether GDB reuses the same inferior across an exec call or
1756 creates a new one. This is useful to be able to restart the old
1757 executable after the inferior having done an exec call.
1759 set default-collect EXPR, ...
1760 show default-collect
1761 Define a list of expressions to be collected at each tracepoint.
1762 This is a useful way to ensure essential items are not overlooked,
1763 such as registers or a critical global variable.
1765 set disconnected-tracing
1766 show disconnected-tracing
1767 If set to 1, the target is instructed to continue tracing if it
1768 loses its connection to GDB. If 0, the target is to stop tracing
1771 set circular-trace-buffer
1772 show circular-trace-buffer
1773 If set to on, the target is instructed to use a circular trace buffer
1774 and discard the oldest trace frames instead of stopping the trace due
1775 to a full trace buffer. If set to off, the trace stops when the buffer
1776 fills up. Some targets may not support this.
1778 set script-extension off|soft|strict
1779 show script-extension
1780 If set to "off", the debugger does not perform any script language
1781 recognition, and all sourced files are assumed to be GDB scripts.
1782 If set to "soft" (the default), files are sourced according to
1783 filename extension, falling back to GDB scripts if the first
1785 If set to "strict", files are sourced according to filename extension.
1787 set ada trust-PAD-over-XVS on|off
1788 show ada trust-PAD-over-XVS
1789 If off, activate a workaround against a bug in the debugging information
1790 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1791 the GCC sources for more information about the GNAT encoding and
1792 PAD types in particular). It is always safe to set this option to
1793 off, but this introduces a slight performance penalty. The default
1796 * Python API Improvements
1798 ** GDB provides the new class gdb.LazyString. This is useful in
1799 some pretty-printing cases. The new method gdb.Value.lazy_string
1800 provides a simple way to create objects of this type.
1802 ** The fields returned by gdb.Type.fields now have an
1803 `is_base_class' attribute.
1805 ** The new method gdb.Type.range returns the range of an array type.
1807 ** The new method gdb.parse_and_eval can be used to parse and
1808 evaluate an expression.
1810 * New remote packets
1813 Define a trace state variable.
1816 Get the current value of a trace state variable.
1819 Set desired tracing behavior upon disconnection.
1822 Set the trace buffer to be linear or circular.
1825 Get data about the tracepoints currently in use.
1829 Process record now works correctly with hardware watchpoints.
1831 Multiple bug fixes have been made to the mips-irix port, making it
1832 much more reliable. In particular:
1833 - Debugging threaded applications is now possible again. Previously,
1834 GDB would hang while starting the program, or while waiting for
1835 the program to stop at a breakpoint.
1836 - Attaching to a running process no longer hangs.
1837 - An error occurring while loading a core file has been fixed.
1838 - Changing the value of the PC register now works again. This fixes
1839 problems observed when using the "jump" command, or when calling
1840 a function from GDB, or even when assigning a new value to $pc.
1841 - With the "finish" and "return" commands, the return value for functions
1842 returning a small array is now correctly printed.
1843 - It is now possible to break on shared library code which gets executed
1844 during a shared library init phase (code executed while executing
1845 their .init section). Previously, the breakpoint would have no effect.
1846 - GDB is now able to backtrace through the signal handler for
1847 non-threaded programs.
1849 PIE (Position Independent Executable) programs debugging is now supported.
1850 This includes debugging execution of PIC (Position Independent Code) shared
1851 libraries although for that, it should be possible to run such libraries as an
1854 *** Changes in GDB 7.0
1856 * GDB now has an interface for JIT compilation. Applications that
1857 dynamically generate code can create symbol files in memory and register
1858 them with GDB. For users, the feature should work transparently, and
1859 for JIT developers, the interface is documented in the GDB manual in the
1860 "JIT Compilation Interface" chapter.
1862 * Tracepoints may now be conditional. The syntax is as for
1863 breakpoints; either an "if" clause appended to the "trace" command,
1864 or the "condition" command is available. GDB sends the condition to
1865 the target for evaluation using the same bytecode format as is used
1866 for tracepoint actions.
1868 * The disassemble command now supports: an optional /r modifier, print the
1869 raw instructions in hex as well as in symbolic form, and an optional /m
1870 modifier to print mixed source+assembly.
1872 * Process record and replay
1874 In a architecture environment that supports ``process record and
1875 replay'', ``process record and replay'' target can record a log of
1876 the process execution, and replay it with both forward and reverse
1879 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1880 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1881 set execution-direction {forward|reverse}, for targets that support
1884 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1885 feature is available with a native GDB running on kernel version
1888 * GDB now has support for multi-byte and wide character sets on the
1889 target. Strings whose character type is wchar_t, char16_t, or
1890 char32_t are now correctly printed. GDB supports wide- and unicode-
1891 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1892 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1893 `printf'. This feature requires iconv to work properly; if your
1894 system does not have a working iconv, GDB can use GNU libiconv. See
1895 the installation instructions for more information.
1897 * GDB now supports automatic retrieval of shared library files from
1898 remote targets. To use this feature, specify a system root that begins
1899 with the `remote:' prefix, either via the `set sysroot' command or via
1900 the `--with-sysroot' configure-time option.
1902 * "info sharedlibrary" now takes an optional regex of libraries to show,
1903 and it now reports if a shared library has no debugging information.
1905 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1906 now complete on file names.
1908 * When completing in expressions, gdb will attempt to limit
1909 completions to allowable structure or union fields, where appropriate.
1910 For instance, consider:
1912 # struct example { int f1; double f2; };
1913 # struct example variable;
1916 If the user types TAB at the end of this command line, the available
1917 completions will be "f1" and "f2".
1919 * Inlined functions are now supported. They show up in backtraces, and
1920 the "step", "next", and "finish" commands handle them automatically.
1922 * GDB now supports the token-splicing (##) and stringification (#)
1923 operators when expanding macros. It also supports variable-arity
1926 * GDB now supports inspecting extra signal information, exported by
1927 the new $_siginfo convenience variable. The feature is currently
1928 implemented on linux ARM, i386 and amd64.
1930 * GDB can now display the VFP floating point registers and NEON vector
1931 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1932 can provide these registers (requires Linux 2.6.30 or later). Remote
1933 and simulator targets may also provide them.
1935 * New remote packets
1938 Search memory for a sequence of bytes.
1941 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1942 operation over reliable transport links. Use of this packet is
1943 controlled by the `set remote noack-packet' command.
1946 Kill the process with the specified process ID. Use this in preference
1947 to `k' when multiprocess protocol extensions are supported.
1950 Obtains additional operating system information
1954 Read or write additional signal information.
1956 * Removed remote protocol undocumented extension
1958 An undocumented extension to the remote protocol's `S' stop reply
1959 packet that permited the stub to pass a process id was removed.
1960 Remote servers should use the `T' stop reply packet instead.
1962 * GDB now supports multiple function calling conventions according to the
1963 DWARF-2 DW_AT_calling_convention function attribute.
1965 * The SH target utilizes the aforementioned change to distinguish between gcc
1966 and Renesas calling convention. It also adds the new CLI commands
1967 `set/show sh calling-convention'.
1969 * GDB can now read compressed debug sections, as produced by GNU gold
1970 with the --compress-debug-sections=zlib flag.
1972 * 64-bit core files are now supported on AIX.
1974 * Thread switching is now supported on Tru64.
1976 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1977 which will be allocated using malloc later in program execution.
1979 * The qXfer:libraries:read remote procotol packet now allows passing a
1980 list of section offsets.
1982 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1983 conditions handling signals delivered during attach or thread creation
1984 have also been fixed.
1986 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1987 From the user's standpoint, all unqualified instances of True and False
1988 are treated as the standard definitions, regardless of context.
1990 * GDB now parses C++ symbol and type names more flexibly. For
1993 template<typename T> class C { };
1996 GDB will now correctly handle all of:
1998 ptype C<char const *>
1999 ptype C<char const*>
2000 ptype C<const char *>
2001 ptype C<const char*>
2003 * New features in the GDB remote stub, gdbserver
2005 - The "--wrapper" command-line argument tells gdbserver to use a
2006 wrapper program to launch programs for debugging.
2008 - On PowerPC and S/390 targets, it is now possible to use a single
2009 gdbserver executable to debug both 32-bit and 64-bit programs.
2010 (This requires gdbserver itself to be built as a 64-bit executable.)
2012 - gdbserver uses the new noack protocol mode for TCP connections to
2013 reduce communications latency, if also supported and enabled in GDB.
2015 - Support for the sparc64-linux-gnu target is now included in
2018 - The amd64-linux build of gdbserver now supports debugging both
2019 32-bit and 64-bit programs.
2021 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2022 now support hardware watchpoints, and will use them automatically
2027 GDB now has support for scripting using Python. Whether this is
2028 available is determined at configure time.
2030 New GDB commands can now be written in Python.
2032 * Ada tasking support
2034 Ada tasks can now be inspected in GDB. The following commands have
2038 Print the list of Ada tasks.
2040 Print detailed information about task number N.
2042 Print the task number of the current task.
2044 Switch the context of debugging to task number N.
2046 * Support for user-defined prefixed commands. The "define" command can
2047 add new commands to existing prefixes, e.g. "target".
2049 * Multi-inferior, multi-process debugging.
2051 GDB now has generalized support for multi-inferior debugging. See
2052 "Debugging Multiple Inferiors" in the manual for more information.
2053 Although availability still depends on target support, the command
2054 set is more uniform now. The GNU/Linux specific multi-forks support
2055 has been migrated to this new framework. This implied some user
2056 visible changes; see "New commands" and also "Removed commands"
2059 * Target descriptions can now describe the target OS ABI. See the
2060 "Target Description Format" section in the user manual for more
2063 * Target descriptions can now describe "compatible" architectures
2064 to indicate that the target can execute applications for a different
2065 architecture in addition to those for the main target architecture.
2066 See the "Target Description Format" section in the user manual for
2069 * Multi-architecture debugging.
2071 GDB now includes general supports for debugging applications on
2072 hybrid systems that use more than one single processor architecture
2073 at the same time. Each such hybrid architecture still requires
2074 specific support to be added. The only hybrid architecture supported
2075 in this version of GDB is the Cell Broadband Engine.
2077 * GDB now supports integrated debugging of Cell/B.E. applications that
2078 use both the PPU and SPU architectures. To enable support for hybrid
2079 Cell/B.E. debugging, you need to configure GDB to support both the
2080 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2081 --enable-targets configure option.
2083 * Non-stop mode debugging.
2085 For some targets, GDB now supports an optional mode of operation in
2086 which you can examine stopped threads while other threads continue
2087 to execute freely. This is referred to as non-stop mode, with the
2088 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2089 section in the user manual for more information.
2091 To be able to support remote non-stop debugging, a remote stub needs
2092 to implement the non-stop mode remote protocol extensions, as
2093 described in the "Remote Non-Stop" section of the user manual. The
2094 GDB remote stub, gdbserver, has been adjusted to support these
2095 extensions on linux targets.
2097 * New commands (for set/show, see "New options" below)
2099 catch syscall [NAME(S) | NUMBER(S)]
2100 Catch system calls. Arguments, which should be names of system
2101 calls or their numbers, mean catch only those syscalls. Without
2102 arguments, every syscall will be caught. When the inferior issues
2103 any of the specified syscalls, GDB will stop and announce the system
2104 call, both when it is called and when its call returns. This
2105 feature is currently available with a native GDB running on the
2106 Linux Kernel, under the following architectures: x86, x86_64,
2107 PowerPC and PowerPC64.
2109 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2111 Search memory for a sequence of bytes.
2113 maint set python print-stack
2114 maint show python print-stack
2115 Show a stack trace when an error is encountered in a Python script.
2118 Invoke CODE by passing it to the Python interpreter.
2123 These allow macros to be defined, undefined, and listed
2127 Show operating system information about processes.
2130 List the inferiors currently under GDB's control.
2133 Switch focus to inferior number NUM.
2136 Detach from inferior number NUM.
2139 Kill inferior number NUM.
2143 set spu stop-on-load
2144 show spu stop-on-load
2145 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2147 set spu auto-flush-cache
2148 show spu auto-flush-cache
2149 Control whether to automatically flush the software-managed cache
2150 during Cell/B.E. debugging.
2152 set sh calling-convention
2153 show sh calling-convention
2154 Control the calling convention used when calling SH target functions.
2157 show debug timestamp
2158 Control display of timestamps with GDB debugging output.
2160 set disassemble-next-line
2161 show disassemble-next-line
2162 Control display of disassembled source lines or instructions when
2165 set remote noack-packet
2166 show remote noack-packet
2167 Set/show the use of remote protocol QStartNoAckMode packet. See above
2168 under "New remote packets."
2170 set remote query-attached-packet
2171 show remote query-attached-packet
2172 Control use of remote protocol `qAttached' (query-attached) packet.
2174 set remote read-siginfo-object
2175 show remote read-siginfo-object
2176 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2179 set remote write-siginfo-object
2180 show remote write-siginfo-object
2181 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2184 set remote reverse-continue
2185 show remote reverse-continue
2186 Control use of remote protocol 'bc' (reverse-continue) packet.
2188 set remote reverse-step
2189 show remote reverse-step
2190 Control use of remote protocol 'bs' (reverse-step) packet.
2192 set displaced-stepping
2193 show displaced-stepping
2194 Control displaced stepping mode. Displaced stepping is a way to
2195 single-step over breakpoints without removing them from the debuggee.
2196 Also known as "out-of-line single-stepping".
2199 show debug displaced
2200 Control display of debugging info for displaced stepping.
2202 maint set internal-error
2203 maint show internal-error
2204 Control what GDB does when an internal error is detected.
2206 maint set internal-warning
2207 maint show internal-warning
2208 Control what GDB does when an internal warning is detected.
2213 Use a wrapper program to launch programs for debugging.
2215 set multiple-symbols (all|ask|cancel)
2216 show multiple-symbols
2217 The value of this variable can be changed to adjust the debugger behavior
2218 when an expression or a breakpoint location contains an ambiguous symbol
2219 name (an overloaded function name, for instance).
2221 set breakpoint always-inserted
2222 show breakpoint always-inserted
2223 Keep breakpoints always inserted in the target, as opposed to inserting
2224 them when resuming the target, and removing them when the target stops.
2225 This option can improve debugger performance on slow remote targets.
2227 set arm fallback-mode (arm|thumb|auto)
2228 show arm fallback-mode
2229 set arm force-mode (arm|thumb|auto)
2231 These commands control how ARM GDB determines whether instructions
2232 are ARM or Thumb. The default for both settings is auto, which uses
2233 the current CPSR value for instructions without symbols; previous
2234 versions of GDB behaved as if "set arm fallback-mode arm".
2236 set disable-randomization
2237 show disable-randomization
2238 Standalone programs run with the virtual address space randomization enabled
2239 by default on some platforms. This option keeps the addresses stable across
2240 multiple debugging sessions.
2244 Control whether other threads are stopped or not when some thread hits
2249 Requests that asynchronous execution is enabled in the target, if available.
2250 In this case, it's possible to resume target in the background, and interact
2251 with GDB while the target is running. "show target-async" displays the
2252 current state of asynchronous execution of the target.
2254 set target-wide-charset
2255 show target-wide-charset
2256 The target-wide-charset is the name of the character set that GDB
2257 uses when printing characters whose type is wchar_t.
2259 set tcp auto-retry (on|off)
2261 set tcp connect-timeout
2262 show tcp connect-timeout
2263 These commands allow GDB to retry failed TCP connections to a remote stub
2264 with a specified timeout period; this is useful if the stub is launched
2265 in parallel with GDB but may not be ready to accept connections immediately.
2267 set libthread-db-search-path
2268 show libthread-db-search-path
2269 Control list of directories which GDB will search for appropriate
2272 set schedule-multiple (on|off)
2273 show schedule-multiple
2274 Allow GDB to resume all threads of all processes or only threads of
2275 the current process.
2279 Use more aggressive caching for accesses to the stack. This improves
2280 performance of remote debugging (particularly backtraces) without
2281 affecting correctness.
2283 set interactive-mode (on|off|auto)
2284 show interactive-mode
2285 Control whether GDB runs in interactive mode (on) or not (off).
2286 When in interactive mode, GDB waits for the user to answer all
2287 queries. Otherwise, GDB does not wait and assumes the default
2288 answer. When set to auto (the default), GDB determines which
2289 mode to use based on the stdin settings.
2294 For program forks, this is replaced by the new more generic `info
2295 inferiors' command. To list checkpoints, you can still use the
2296 `info checkpoints' command, which was an alias for the `info forks'
2300 Replaced by the new `inferior' command. To switch between
2301 checkpoints, you can still use the `restart' command, which was an
2302 alias for the `fork' command.
2305 This is removed, since some targets don't have a notion of
2306 processes. To switch between processes, you can still use the
2307 `inferior' command using GDB's own inferior number.
2310 For program forks, this is replaced by the new more generic `kill
2311 inferior' command. To delete a checkpoint, you can still use the
2312 `delete checkpoint' command, which was an alias for the `delete
2316 For program forks, this is replaced by the new more generic `detach
2317 inferior' command. To detach a checkpoint, you can still use the
2318 `detach checkpoint' command, which was an alias for the `detach
2321 * New native configurations
2323 x86/x86_64 Darwin i[34567]86-*-darwin*
2325 x86_64 MinGW x86_64-*-mingw*
2329 Lattice Mico32 lm32-*
2330 x86 DICOS i[34567]86-*-dicos*
2331 x86_64 DICOS x86_64-*-dicos*
2334 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2335 (mingw32ce) debugging.
2341 These commands were actually not implemented on any target.
2343 *** Changes in GDB 6.8
2345 * New native configurations
2347 NetBSD/hppa hppa*-*netbsd*
2348 Xtensa GNU/Linux xtensa*-*-linux*
2352 NetBSD/hppa hppa*-*-netbsd*
2353 Xtensa GNU/Lunux xtensa*-*-linux*
2355 * Change in command line behavior -- corefiles vs. process ids.
2357 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2358 attaching to process NUMBER fails, GDB no longer attempts to open a
2359 core file named NUMBER. Attaching to a program using the -c option
2360 is no longer supported. Instead, use the '-p' or '--pid' options.
2362 * GDB can now be built as a native debugger for debugging Windows x86
2363 (mingw32) Portable Executable (PE) programs.
2365 * Pending breakpoints no longer change their number when their address
2368 * GDB now supports breakpoints with multiple locations,
2369 including breakpoints on C++ constructors, inside C++ templates,
2370 and in inlined functions.
2372 * GDB's ability to debug optimized code has been improved. GDB more
2373 accurately identifies function bodies and lexical blocks that occupy
2374 more than one contiguous range of addresses.
2376 * Target descriptions can now describe registers for PowerPC.
2378 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2379 registers on PowerPC targets.
2381 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2382 targets even when the libthread_db library is not available.
2384 * The GDB remote stub, gdbserver, now supports the new file transfer
2385 commands (remote put, remote get, and remote delete).
2387 * The GDB remote stub, gdbserver, now supports run and attach in
2388 extended-remote mode.
2390 * hppa*64*-*-hpux11* target broken
2391 The debugger is unable to start a program and fails with the following
2392 error: "Error trying to get information about dynamic linker".
2393 The gdb-6.7 release is also affected.
2395 * GDB now supports the --enable-targets= configure option to allow
2396 building a single GDB executable that supports multiple remote
2397 target architectures.
2399 * GDB now supports debugging C and C++ programs which use the
2400 Decimal Floating Point extension. In addition, the PowerPC target
2401 now has a set of pseudo-registers to inspect decimal float values
2402 stored in two consecutive float registers.
2404 * The -break-insert MI command can optionally create pending
2407 * Improved support for debugging Ada
2408 Many improvements to the Ada language support have been made. These
2410 - Better support for Ada2005 interface types
2411 - Improved handling of arrays and slices in general
2412 - Better support for Taft-amendment types
2413 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2415 - Improved command completion in Ada
2418 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2423 set print frame-arguments (all|scalars|none)
2424 show print frame-arguments
2425 The value of this variable can be changed to control which argument
2426 values should be printed by the debugger when displaying a frame.
2431 Transfer files to and from a remote target, and delete remote files.
2438 Transfer files to and from a remote target, and delete remote files.
2440 * New remote packets
2447 Open, close, read, write, and delete files on the remote system.
2450 Attach to an existing process on the remote system, in extended-remote
2454 Run a new process on the remote system, in extended-remote mode.
2456 *** Changes in GDB 6.7
2458 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2459 bfd, libiberty and opcodes, as revealed by static analysis donated by
2460 Coverity, Inc. (http://scan.coverity.com).
2462 * When looking up multiply-defined global symbols, GDB will now prefer the
2463 symbol definition in the current shared library if it was built using the
2464 -Bsymbolic linker option.
2466 * When the Text User Interface (TUI) is not configured, GDB will now
2467 recognize the -tui command-line option and print a message that the TUI
2470 * The GDB remote stub, gdbserver, now has lower overhead for high
2471 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2473 * GDB for MIPS targets now autodetects whether a remote target provides
2474 32-bit or 64-bit register values.
2476 * Support for C++ member pointers has been improved.
2478 * GDB now understands XML target descriptions, which specify the
2479 target's overall architecture. GDB can read a description from
2480 a local file or over the remote serial protocol.
2482 * Vectors of single-byte data use a new integer type which is not
2483 automatically displayed as character or string data.
2485 * The /s format now works with the print command. It displays
2486 arrays of single-byte integers and pointers to single-byte integers
2489 * Target descriptions can now describe target-specific registers,
2490 for architectures which have implemented the support (currently
2491 only ARM, M68K, and MIPS).
2493 * GDB and the GDB remote stub, gdbserver, now support the XScale
2496 * The GDB remote stub, gdbserver, has been updated to support
2497 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2498 has been rewritten to use the standard GDB remote protocol.
2500 * GDB can now step into C++ functions which are called through thunks.
2502 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2504 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2505 layout. It also supports a TextSeg= and DataSeg= response when only
2506 segment base addresses (rather than offsets) are available.
2508 * The /i format now outputs any trailing branch delay slot instructions
2509 immediately following the last instruction within the count specified.
2511 * The GDB remote protocol "T" stop reply packet now supports a
2512 "library" response. Combined with the new "qXfer:libraries:read"
2513 packet, this response allows GDB to debug shared libraries on targets
2514 where the operating system manages the list of loaded libraries (e.g.
2515 Windows and SymbianOS).
2517 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2518 (DLLs) on Windows and Windows CE targets.
2520 * GDB now supports a faster verification that a .debug file matches its binary
2521 according to its build-id signature, if the signature is present.
2527 Enable or disable hardware flow control (RTS/CTS) on the serial port
2528 when debugging using remote targets.
2530 set mem inaccessible-by-default
2531 show mem inaccessible-by-default
2532 If the target supplies a memory map, for instance via the remote
2533 protocol's "qXfer:memory-map:read" packet, setting this variable
2534 prevents GDB from accessing memory outside the memory map. This
2535 is useful for targets with memory mapped registers or which react
2536 badly to accesses of unmapped address space.
2538 set breakpoint auto-hw
2539 show breakpoint auto-hw
2540 If the target supplies a memory map, for instance via the remote
2541 protocol's "qXfer:memory-map:read" packet, setting this variable
2542 lets GDB use hardware breakpoints automatically for memory regions
2543 where it can not use software breakpoints. This covers both the
2544 "break" command and internal breakpoints used for other commands
2545 including "next" and "finish".
2548 catch exception unhandled
2549 Stop the program execution when Ada exceptions are raised.
2552 Stop the program execution when an Ada assertion failed.
2556 Set an alternate system root for target files. This is a more
2557 general version of "set solib-absolute-prefix", which is now
2558 an alias to "set sysroot".
2561 Provide extended SPU facility status information. This set of
2562 commands is available only when debugging the Cell/B.E. SPU
2565 * New native configurations
2567 OpenBSD/sh sh*-*openbsd*
2570 unset tdesc filename
2572 Use the specified local file as an XML target description, and do
2573 not query the target for its built-in description.
2577 OpenBSD/sh sh*-*-openbsd*
2578 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2579 Toshiba Media Processor mep-elf
2581 * New remote packets
2584 Ignore the specified signals; pass them directly to the debugged program
2585 without stopping other threads or reporting them to GDB.
2587 qXfer:features:read:
2588 Read an XML target description from the target, which describes its
2593 Read or write contents of an spufs file on the target system. These
2594 packets are available only on the Cell/B.E. SPU architecture.
2596 qXfer:libraries:read:
2597 Report the loaded shared libraries. Combined with new "T" packet
2598 response, this packet allows GDB to debug shared libraries on
2599 targets where the operating system manages the list of loaded
2600 libraries (e.g. Windows and SymbianOS).
2604 Support for these obsolete configurations has been removed.
2612 i[34567]86-*-lynxos*
2613 i[34567]86-*-netware*
2614 i[34567]86-*-sco3.2v5*
2615 i[34567]86-*-sco3.2v4*
2617 i[34567]86-*-sysv4.2*
2620 i[34567]86-*-unixware2*
2621 i[34567]86-*-unixware*
2630 * Other removed features
2637 Various m68k-only ROM monitors.
2644 Various Renesas ROM monitors and debugging interfaces for SH and
2649 Support for a Macraigor serial interface to on-chip debugging.
2650 GDB does not directly support the newer parallel or USB
2655 A debug information format. The predecessor to DWARF 2 and
2656 DWARF 3, which are still supported.
2658 Support for the HP aCC compiler on HP-UX/PA-RISC
2660 SOM-encapsulated symbolic debugging information, automatic
2661 invocation of pxdb, and the aCC custom C++ ABI. This does not
2662 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2663 with aCC can still be debugged on an assembly level.
2665 MIPS ".pdr" sections
2667 A MIPS-specific format used to describe stack frame layout
2668 in debugging information.
2672 GDB could work with an older version of Guile to debug
2673 the interpreter and Scheme programs running in it.
2675 set mips stack-arg-size
2676 set mips saved-gpreg-size
2678 Use "set mips abi" to control parameter passing for MIPS.
2680 *** Changes in GDB 6.6
2685 Cell Broadband Engine SPU spu-elf
2687 * GDB can now be configured as a cross-debugger targeting native Windows
2688 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2689 running on a Windows system over TCP/IP to debug Windows programs.
2691 * The GDB remote stub, gdbserver, has been updated to support Windows and
2692 Cygwin debugging. Both single-threaded and multi-threaded programs are
2695 * The "set trust-readonly-sections" command works again. This command was
2696 broken in GDB 6.3, 6.4, and 6.5.
2698 * The "load" command now supports writing to flash memory, if the remote
2699 stub provides the required support.
2701 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2702 longer requires symbolic debug information (e.g. DWARF-2).
2707 unset substitute-path
2708 show substitute-path
2709 Manage a list of substitution rules that GDB uses to rewrite the name
2710 of the directories where the sources are located. This can be useful
2711 for instance when the sources were moved to a different location
2712 between compilation and debugging.
2716 Print each CLI command as it is executed. Each command is prefixed with
2717 a number of `+' symbols representing the nesting depth.
2718 The source command now has a `-v' option to enable the same feature.
2722 The ARM Demon monitor support (RDP protocol, "target rdp").
2724 Kernel Object Display, an embedded debugging feature which only worked with
2725 an obsolete version of Cisco IOS.
2727 The 'set download-write-size' and 'show download-write-size' commands.
2729 * New remote packets
2732 Tell a stub about GDB client features, and request remote target features.
2733 The first feature implemented is PacketSize, which allows the target to
2734 specify the size of packets it can handle - to minimize the number of
2735 packets required and improve performance when connected to a remote
2739 Fetch an OS auxilliary vector from the remote stub. This packet is a
2740 more efficient replacement for qPart:auxv:read.
2742 qXfer:memory-map:read:
2743 Fetch a memory map from the remote stub, including information about
2744 RAM, ROM, and flash memory devices.
2749 Erase and program a flash memory device.
2751 * Removed remote packets
2754 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2755 used it, and only gdbserver implemented it.
2757 *** Changes in GDB 6.5
2761 Renesas M32C/M16C m32c-elf
2763 Morpho Technologies ms1 ms1-elf
2767 init-if-undefined Initialize a convenience variable, but
2768 only if it doesn't already have a value.
2770 The following commands are presently only implemented for native GNU/Linux:
2772 checkpoint Save a snapshot of the program state.
2774 restart <n> Return the program state to a
2775 previously saved state.
2777 info checkpoints List currently saved checkpoints.
2779 delete-checkpoint <n> Delete a previously saved checkpoint.
2781 set|show detach-on-fork Tell gdb whether to detach from a newly
2782 forked process, or to keep debugging it.
2784 info forks List forks of the user program that
2785 are available to be debugged.
2787 fork <n> Switch to debugging one of several
2788 forks of the user program that are
2789 available to be debugged.
2791 delete-fork <n> Delete a fork from the list of forks
2792 that are available to be debugged (and
2793 kill the forked process).
2795 detach-fork <n> Delete a fork from the list of forks
2796 that are available to be debugged (and
2797 allow the process to continue).
2801 Morpho Technologies ms2 ms1-elf
2803 * Improved Windows host support
2805 GDB now builds as a cross debugger hosted on i686-mingw32, including
2806 native console support, and remote communications using either
2807 network sockets or serial ports.
2809 * Improved Modula-2 language support
2811 GDB can now print most types in the Modula-2 syntax. This includes:
2812 basic types, set types, record types, enumerated types, range types,
2813 pointer types and ARRAY types. Procedure var parameters are correctly
2814 printed and hexadecimal addresses and character constants are also
2815 written in the Modula-2 syntax. Best results can be obtained by using
2816 GNU Modula-2 together with the -gdwarf-2 command line option.
2820 The ARM rdi-share module.
2822 The Netware NLM debug server.
2824 *** Changes in GDB 6.4
2826 * New native configurations
2828 OpenBSD/arm arm*-*-openbsd*
2829 OpenBSD/mips64 mips64-*-openbsd*
2833 Morpho Technologies ms1 ms1-elf
2835 * New command line options
2837 --batch-silent As for --batch, but totally silent.
2838 --return-child-result The debugger will exist with the same value
2839 the child (debugged) program exited with.
2840 --eval-command COMMAND, -ex COMMAND
2841 Execute a single GDB CLI command. This may be
2842 specified multiple times and in conjunction
2843 with the --command (-x) option.
2845 * Deprecated commands removed
2847 The following commands, that were deprecated in 2000, have been
2851 set|show arm disassembly-flavor set|show arm disassembler
2852 othernames set arm disassembler
2853 set|show remotedebug set|show debug remote
2854 set|show archdebug set|show debug arch
2855 set|show eventdebug set|show debug event
2858 * New BSD user-level threads support
2860 It is now possible to debug programs using the user-level threads
2861 library on OpenBSD and FreeBSD. Currently supported (target)
2864 FreeBSD/amd64 x86_64-*-freebsd*
2865 FreeBSD/i386 i386-*-freebsd*
2866 OpenBSD/i386 i386-*-openbsd*
2868 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2869 are not yet supported.
2871 * New support for Matsushita MN10300 w/sim added
2872 (Work in progress). mn10300-elf.
2874 * REMOVED configurations and files
2876 VxWorks and the XDR protocol *-*-vxworks
2877 Motorola MCORE mcore-*-*
2878 National Semiconductor NS32000 ns32k-*-*
2880 * New "set print array-indexes" command
2882 After turning this setting "on", GDB prints the index of each element
2883 when displaying arrays. The default is "off" to preserve the previous
2886 * VAX floating point support
2888 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2890 * User-defined command support
2892 In addition to using $arg0..$arg9 for argument passing, it is now possible
2893 to use $argc to determine now many arguments have been passed. See the
2894 section on user-defined commands in the user manual for more information.
2896 *** Changes in GDB 6.3:
2898 * New command line option
2900 GDB now accepts -l followed by a number to set the timeout for remote
2903 * GDB works with GCC -feliminate-dwarf2-dups
2905 GDB now supports a more compact representation of DWARF-2 debug
2906 information using DW_FORM_ref_addr references. These are produced
2907 by GCC with the option -feliminate-dwarf2-dups and also by some
2908 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2909 to use -feliminate-dwarf2-dups.
2911 * Internationalization
2913 When supported by the host system, GDB will be built with
2914 internationalization (libintl). The task of marking up the sources is
2915 continued, we're looking forward to our first translation.
2919 Initial support for debugging programs compiled with the GNAT
2920 implementation of the Ada programming language has been integrated
2921 into GDB. In this release, support is limited to expression evaluation.
2923 * New native configurations
2925 GNU/Linux/m32r m32r-*-linux-gnu
2929 GDB's remote protocol now includes support for the 'p' packet. This
2930 packet is used to fetch individual registers from a remote inferior.
2932 * END-OF-LIFE registers[] compatibility module
2934 GDB's internal register infrastructure has been completely rewritten.
2935 The new infrastructure making possible the implementation of key new
2936 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2939 GDB 6.3 will be the last release to include the the registers[]
2940 compatibility module that allowed out-of-date configurations to
2941 continue to work. This change directly impacts the following
2951 powerpc bdm protocol
2953 Unless there is activity to revive these configurations, they will be
2954 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2956 * OBSOLETE configurations and files
2958 Configurations that have been declared obsolete in this release have
2959 been commented out. Unless there is activity to revive these
2960 configurations, the next release of GDB will have their sources
2961 permanently REMOVED.
2970 *** Changes in GDB 6.2.1:
2972 * MIPS `break main; run' gave an heuristic-fence-post warning
2974 When attempting to run even a simple program, a warning about
2975 heuristic-fence-post being hit would be reported. This problem has
2978 * MIPS IRIX 'long double' crashed GDB
2980 When examining a long double variable, GDB would get a segmentation
2981 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2982 IRIX long double values).
2986 A bug in the VAX stack code was causing problems with the "next"
2987 command. This problem has been fixed.
2989 *** Changes in GDB 6.2:
2991 * Fix for ``many threads''
2993 On GNU/Linux systems that use the NPTL threads library, a program
2994 rapidly creating and deleting threads would confuse GDB leading to the
2997 ptrace: No such process.
2998 thread_db_get_info: cannot get thread info: generic error
3000 This problem has been fixed.
3002 * "-async" and "-noasync" options removed.
3004 Support for the broken "-noasync" option has been removed (it caused
3007 * New ``start'' command.
3009 This command runs the program until the begining of the main procedure.
3011 * New BSD Kernel Data Access Library (libkvm) interface
3013 Using ``target kvm'' it is now possible to debug kernel core dumps and
3014 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3015 platforms. Currently supported (native-only) configurations are:
3017 FreeBSD/amd64 x86_64-*-freebsd*
3018 FreeBSD/i386 i?86-*-freebsd*
3019 NetBSD/i386 i?86-*-netbsd*
3020 NetBSD/m68k m68*-*-netbsd*
3021 NetBSD/sparc sparc-*-netbsd*
3022 OpenBSD/amd64 x86_64-*-openbsd*
3023 OpenBSD/i386 i?86-*-openbsd*
3024 OpenBSD/m68k m68*-openbsd*
3025 OpenBSD/sparc sparc-*-openbsd*
3027 * Signal trampoline code overhauled
3029 Many generic problems with GDB's signal handling code have been fixed.
3030 These include: backtraces through non-contiguous stacks; recognition
3031 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3032 call; backtrace through a signal trampoline; step into and out of
3033 signal handlers; and single-stepping in the signal trampoline.
3035 Please note that kernel bugs are a limiting factor here. These
3036 features have been shown to work on an s390 GNU/Linux system that
3037 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3039 * Cygwin support for DWARF 2 added.
3041 * New native configurations
3043 GNU/Linux/hppa hppa*-*-linux*
3044 OpenBSD/hppa hppa*-*-openbsd*
3045 OpenBSD/m68k m68*-*-openbsd*
3046 OpenBSD/m88k m88*-*-openbsd*
3047 OpenBSD/powerpc powerpc-*-openbsd*
3048 NetBSD/vax vax-*-netbsd*
3049 OpenBSD/vax vax-*-openbsd*
3051 * END-OF-LIFE frame compatibility module
3053 GDB's internal frame infrastructure has been completely rewritten.
3054 The new infrastructure making it possible to support key new features
3055 including DWARF 2 Call Frame Information. To aid in the task of
3056 migrating old configurations to this new infrastructure, a
3057 compatibility module, that allowed old configurations to continue to
3058 work, was also included.
3060 GDB 6.2 will be the last release to include this frame compatibility
3061 module. This change directly impacts the following configurations:
3071 Unless there is activity to revive these configurations, they will be
3072 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3074 * REMOVED configurations and files
3076 Sun 3, running SunOS 3 m68*-*-sunos3*
3077 Sun 3, running SunOS 4 m68*-*-sunos4*
3078 Sun 2, running SunOS 3 m68000-*-sunos3*
3079 Sun 2, running SunOS 4 m68000-*-sunos4*
3080 Motorola 680x0 running LynxOS m68*-*-lynxos*
3081 AT&T 3b1/Unix pc m68*-att-*
3082 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3083 decstation mips-dec-* mips-little-*
3084 riscos mips-*-riscos* mips-*-sysv*
3085 sonymips mips-sony-*
3086 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3088 *** Changes in GDB 6.1.1:
3090 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3092 The TUI (Text-mode User Interface) is now built as part of a default
3093 GDB configuration. It is enabled by either selecting the TUI with the
3094 command line option "-i=tui" or by running the separate "gdbtui"
3095 program. For more information on the TUI, see the manual "Debugging
3098 * Pending breakpoint support (also included in GDB 6.1)
3100 Support has been added to allow you to specify breakpoints in shared
3101 libraries that have not yet been loaded. If a breakpoint location
3102 cannot be found, and the "breakpoint pending" option is set to auto,
3103 GDB queries you if you wish to make the breakpoint pending on a future
3104 shared-library load. If and when GDB resolves the breakpoint symbol,
3105 the pending breakpoint is removed as one or more regular breakpoints
3108 Pending breakpoints are very useful for GCJ Java debugging.
3110 * Fixed ISO-C build problems
3112 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3113 non ISO-C code that stopped them being built using a more strict ISO-C
3114 compiler (e.g., IBM's C compiler).
3116 * Fixed build problem on IRIX 5
3118 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3119 wasn't able to compile compile on an IRIX 5 system.
3121 * Added execute permission to gdb/gdbserver/configure
3123 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3124 permission. This bug would cause configure to fail on a number of
3125 systems (Solaris, IRIX). Ref: server/519.
3127 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3129 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3130 has been updated to use constant array sizes.
3132 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3134 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3135 its generated DWARF Call Frame Info. This encoding was causing GDB to
3136 panic, that panic has been fixed. Ref: gdb/1628.
3138 * Fixed a problem when examining parameters in shared library code.
3140 When examining parameters in optimized shared library code generated
3141 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3142 not available''. GDB now correctly displays the variable's value.
3144 *** Changes in GDB 6.1:
3146 * Removed --with-mmalloc
3148 Support for the mmalloc memory manager has been removed, as it
3149 conflicted with the internal gdb byte cache.
3151 * Changes in AMD64 configurations
3153 The AMD64 target now includes the %cs and %ss registers. As a result
3154 the AMD64 remote protocol has changed; this affects the floating-point
3155 and SSE registers. If you rely on those registers for your debugging,
3156 you should upgrade gdbserver on the remote side.
3158 * Revised SPARC target
3160 The SPARC target has been completely revised, incorporating the
3161 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3162 support for LynxOS and SunOS 4 has been dropped. Calling functions
3163 from within GDB on operating systems with a non-executable stack
3164 (Solaris, OpenBSD) now works.
3168 GDB has a new C++ demangler which does a better job on the mangled
3169 names generated by current versions of g++. It also runs faster, so
3170 with this and other changes gdb should now start faster on large C++
3173 * DWARF 2 Location Expressions
3175 GDB support for location expressions has been extended to support function
3176 arguments and frame bases. Older versions of GDB could crash when they
3179 * C++ nested types and namespaces
3181 GDB's support for nested types and namespaces in C++ has been
3182 improved, especially if you use the DWARF 2 debugging format. (This
3183 is the default for recent versions of GCC on most platforms.)
3184 Specifically, if you have a class "Inner" defined within a class or
3185 namespace "Outer", then GDB realizes that the class's name is
3186 "Outer::Inner", not simply "Inner". This should greatly reduce the
3187 frequency of complaints about not finding RTTI symbols. In addition,
3188 if you are stopped at inside of a function defined within a namespace,
3189 GDB modifies its name lookup accordingly.
3191 * New native configurations
3193 NetBSD/amd64 x86_64-*-netbsd*
3194 OpenBSD/amd64 x86_64-*-openbsd*
3195 OpenBSD/alpha alpha*-*-openbsd*
3196 OpenBSD/sparc sparc-*-openbsd*
3197 OpenBSD/sparc64 sparc64-*-openbsd*
3199 * New debugging protocols
3201 M32R with SDI protocol m32r-*-elf*
3203 * "set prompt-escape-char" command deleted.
3205 The command "set prompt-escape-char" has been deleted. This command,
3206 and its very obscure effet on GDB's prompt, was never documented,
3207 tested, nor mentioned in the NEWS file.
3209 * OBSOLETE configurations and files
3211 Configurations that have been declared obsolete in this release have
3212 been commented out. Unless there is activity to revive these
3213 configurations, the next release of GDB will have their sources
3214 permanently REMOVED.
3216 Sun 3, running SunOS 3 m68*-*-sunos3*
3217 Sun 3, running SunOS 4 m68*-*-sunos4*
3218 Sun 2, running SunOS 3 m68000-*-sunos3*
3219 Sun 2, running SunOS 4 m68000-*-sunos4*
3220 Motorola 680x0 running LynxOS m68*-*-lynxos*
3221 AT&T 3b1/Unix pc m68*-att-*
3222 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3223 decstation mips-dec-* mips-little-*
3224 riscos mips-*-riscos* mips-*-sysv*
3225 sonymips mips-sony-*
3226 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3228 * REMOVED configurations and files
3230 SGI Irix-4.x mips-sgi-irix4 or iris4
3231 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3232 Z8000 simulator z8k-zilog-none or z8ksim
3233 Matsushita MN10200 w/simulator mn10200-*-*
3234 H8/500 simulator h8500-hitachi-hms or h8500hms
3235 HP/PA running BSD hppa*-*-bsd*
3236 HP/PA running OSF/1 hppa*-*-osf*
3237 HP/PA Pro target hppa*-*-pro*
3238 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3239 386BSD i[3456]86-*-bsd*
3240 Sequent family i[3456]86-sequent-sysv4*
3241 i[3456]86-sequent-sysv*
3242 i[3456]86-sequent-bsd*
3243 SPARC running LynxOS sparc-*-lynxos*
3244 SPARC running SunOS 4 sparc-*-sunos4*
3245 Tsqware Sparclet sparclet-*-*
3246 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3248 *** Changes in GDB 6.0:
3252 Support for debugging the Objective-C programming language has been
3253 integrated into GDB.
3255 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3257 DWARF 2's Call Frame Information makes available compiler generated
3258 information that more exactly describes the program's run-time stack.
3259 By using this information, GDB is able to provide more robust stack
3262 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3263 have been updated to use a new backtrace mechanism which includes
3264 DWARF 2 CFI support.
3268 GDB's remote protocol has been extended to include support for hosted
3269 file I/O (where the remote target uses GDB's file system). See GDB's
3270 remote protocol documentation for details.
3272 * All targets using the new architecture framework.
3274 All of GDB's targets have been updated to use the new internal
3275 architecture framework. The way is now open for future GDB releases
3276 to include cross-architecture native debugging support (i386 on amd64,
3279 * GNU/Linux's Thread Local Storage (TLS)
3281 GDB now includes support for for the GNU/Linux implementation of
3282 per-thread variables.
3284 * GNU/Linux's Native POSIX Thread Library (NPTL)
3286 GDB's thread code has been updated to work with either the new
3287 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3289 * Separate debug info.
3291 GDB, in conjunction with BINUTILS, now supports a mechanism for
3292 automatically loading debug information from a separate file. Instead
3293 of shipping full debug and non-debug versions of system libraries,
3294 system integrators can now instead ship just the stripped libraries
3295 and optional debug files.
3297 * DWARF 2 Location Expressions
3299 DWARF 2 Location Expressions allow the compiler to more completely
3300 describe the location of variables (even in optimized code) to the
3303 GDB now includes preliminary support for location expressions (support
3304 for DW_OP_piece is still missing).
3308 A number of long standing bugs that caused GDB to die while starting a
3309 Java application have been fixed. GDB's Java support is now
3310 considered "useable".
3312 * GNU/Linux support for fork, vfork, and exec.
3314 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3315 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3318 * GDB supports logging output to a file
3320 There are two new commands, "set logging" and "show logging", which can be
3321 used to capture GDB's output to a file.
3323 * The meaning of "detach" has changed for gdbserver
3325 The "detach" command will now resume the application, as documented. To
3326 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3329 * d10v, m68hc11 `regs' command deprecated
3331 The `info registers' command has been updated so that it displays the
3332 registers using a format identical to the old `regs' command.
3336 A new command, "maint set profile on/off", has been added. This command can
3337 be used to enable or disable profiling while running GDB, to profile a
3338 session or a set of commands. In addition there is a new configure switch,
3339 "--enable-profiling", which will cause GDB to be compiled with profiling
3340 data, for more informative profiling results.
3342 * Default MI syntax changed to "mi2".
3344 The default MI (machine interface) syntax, enabled by the command line
3345 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3346 "mi1", can be enabled by specifying the option "-i=mi1".
3348 Support for the original "mi0" syntax (included in GDB 5.0) has been
3351 Fix for gdb/192: removed extraneous space when displaying frame level.
3352 Fix for gdb/672: update changelist is now output in mi list format.
3353 Fix for gdb/702: a -var-assign that updates the value now shows up
3354 in a subsequent -var-update.
3356 * New native configurations.
3358 FreeBSD/amd64 x86_64-*-freebsd*
3360 * Multi-arched targets.
3362 HP/PA HPUX11 hppa*-*-hpux*
3363 Renesas M32R/D w/simulator m32r-*-elf*
3365 * OBSOLETE configurations and files
3367 Configurations that have been declared obsolete in this release have
3368 been commented out. Unless there is activity to revive these
3369 configurations, the next release of GDB will have their sources
3370 permanently REMOVED.
3372 Z8000 simulator z8k-zilog-none or z8ksim
3373 Matsushita MN10200 w/simulator mn10200-*-*
3374 H8/500 simulator h8500-hitachi-hms or h8500hms
3375 HP/PA running BSD hppa*-*-bsd*
3376 HP/PA running OSF/1 hppa*-*-osf*
3377 HP/PA Pro target hppa*-*-pro*
3378 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3379 Sequent family i[3456]86-sequent-sysv4*
3380 i[3456]86-sequent-sysv*
3381 i[3456]86-sequent-bsd*
3382 Tsqware Sparclet sparclet-*-*
3383 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3385 * REMOVED configurations and files
3388 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3389 IBM AIX PS/2 i[3456]86-*-aix
3390 i386 running Mach 3.0 i[3456]86-*-mach3*
3391 i386 running Mach i[3456]86-*-mach*
3392 i386 running OSF/1 i[3456]86-*osf1mk*
3393 HP/Apollo 68k Family m68*-apollo*-sysv*,
3395 m68*-hp-bsd*, m68*-hp-hpux*
3396 Argonaut Risc Chip (ARC) arc-*-*
3397 Mitsubishi D30V d30v-*-*
3398 Fujitsu FR30 fr30-*-elf*
3399 OS/9000 i[34]86-*-os9k
3400 I960 with MON960 i960-*-coff
3402 * MIPS $fp behavior changed
3404 The convenience variable $fp, for the MIPS, now consistently returns
3405 the address of the current frame's base. Previously, depending on the
3406 context, $fp could refer to either $sp or the current frame's base
3407 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3408 The GNU Source-Level Debugger''.
3410 *** Changes in GDB 5.3:
3412 * GNU/Linux shared library multi-threaded performance improved.
3414 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3415 `/proc', in preference to `ptrace' for memory reads. This may result
3416 in an improvement in the start-up time of multi-threaded, shared
3417 library applications when run under GDB. One GDB user writes: ``loads
3418 shared libs like mad''.
3420 * ``gdbserver'' now supports multi-threaded applications on some targets
3422 Support for debugging multi-threaded applications which use
3423 the GNU/Linux LinuxThreads package has been added for
3424 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3425 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3427 * GDB now supports C/C++ preprocessor macros.
3429 GDB now expands preprocessor macro invocations in C/C++ expressions,
3430 and provides various commands for showing macro definitions and how
3433 The new command `macro expand EXPRESSION' expands any macro
3434 invocations in expression, and shows the result.
3436 The new command `show macro MACRO-NAME' shows the definition of the
3437 macro named MACRO-NAME, and where it was defined.
3439 Most compilers don't include information about macros in the debugging
3440 information by default. In GCC 3.1, for example, you need to compile
3441 your program with the options `-gdwarf-2 -g3'. If the macro
3442 information is present in the executable, GDB will read it.
3444 * Multi-arched targets.
3446 DEC Alpha (partial) alpha*-*-*
3447 DEC VAX (partial) vax-*-*
3449 National Semiconductor NS32000 (partial) ns32k-*-*
3450 Motorola 68000 (partial) m68k-*-*
3451 Motorola MCORE mcore-*-*
3455 Fujitsu FRV architecture added by Red Hat frv*-*-*
3458 * New native configurations
3460 Alpha NetBSD alpha*-*-netbsd*
3461 SH NetBSD sh*-*-netbsdelf*
3462 MIPS NetBSD mips*-*-netbsd*
3463 UltraSPARC NetBSD sparc64-*-netbsd*
3465 * OBSOLETE configurations and files
3467 Configurations that have been declared obsolete in this release have
3468 been commented out. Unless there is activity to revive these
3469 configurations, the next release of GDB will have their sources
3470 permanently REMOVED.
3472 Mitsubishi D30V d30v-*-*
3473 OS/9000 i[34]86-*-os9k
3474 IBM AIX PS/2 i[3456]86-*-aix
3475 Fujitsu FR30 fr30-*-elf*
3476 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3477 Argonaut Risc Chip (ARC) arc-*-*
3478 i386 running Mach 3.0 i[3456]86-*-mach3*
3479 i386 running Mach i[3456]86-*-mach*
3480 i386 running OSF/1 i[3456]86-*osf1mk*
3481 HP/Apollo 68k Family m68*-apollo*-sysv*,
3483 m68*-hp-bsd*, m68*-hp-hpux*
3484 I960 with MON960 i960-*-coff
3486 * OBSOLETE languages
3488 CHILL, a Pascal like language used by telecommunications companies.
3490 * REMOVED configurations and files
3492 AMD 29k family via UDI a29k-amd-udi, udi29k
3493 A29K VxWorks a29k-*-vxworks
3494 AMD 29000 embedded, using EBMON a29k-none-none
3495 AMD 29000 embedded with COFF a29k-none-coff
3496 AMD 29000 embedded with a.out a29k-none-aout
3498 testsuite/gdb.hp/gdb.threads-hp/ directory
3500 * New command "set max-user-call-depth <nnn>"
3502 This command allows the user to limit the call depth of user-defined
3503 commands. The default is 1024.
3505 * Changes in FreeBSD/i386 native debugging.
3507 Support for the "generate-core-file" has been added.
3509 * New commands "dump", "append", and "restore".
3511 These commands allow data to be copied from target memory
3512 to a bfd-format or binary file (dump and append), and back
3513 from a file into memory (restore).
3515 * Improved "next/step" support on multi-processor Alpha Tru64.
3517 The previous single-step mechanism could cause unpredictable problems,
3518 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3519 of a software single-step mechanism prevents this.
3521 *** Changes in GDB 5.2.1:
3529 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3530 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3531 Fix, by Joel Brobecker imported from mainline.
3533 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3534 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3535 Fix, by Fred Fish, imported from mainline.
3537 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3538 Surprisingly enough, it works now.
3539 By Michal Ludvig, imported from mainline.
3541 i386 hardware watchpoint support:
3542 avoid misses on second run for some targets.
3543 By Pierre Muller, imported from mainline.
3545 *** Changes in GDB 5.2:
3547 * New command "set trust-readonly-sections on[off]".
3549 This command is a hint that tells gdb that read-only sections
3550 really are read-only (ie. that their contents will not change).
3551 In this mode, gdb will go to the object file rather than the
3552 target to read memory from read-only sections (such as ".text").
3553 This can be a significant performance improvement on some
3554 (notably embedded) targets.
3556 * New command "generate-core-file" (or "gcore").
3558 This new gdb command allows the user to drop a core file of the child
3559 process state at any time. So far it's been implemented only for
3560 GNU/Linux and Solaris, but should be relatively easily ported to other
3561 hosts. Argument is core file name (defaults to core.<pid>).
3563 * New command line option
3565 GDB now accepts --pid or -p followed by a process id.
3567 * Change in command line behavior -- corefiles vs. process ids.
3569 There is a subtle behavior in the way in which GDB handles
3570 command line arguments. The first non-flag argument is always
3571 a program to debug, but the second non-flag argument may either
3572 be a corefile or a process id. Previously, GDB would attempt to
3573 open the second argument as a corefile, and if that failed, would
3574 issue a superfluous error message and then attempt to attach it as
3575 a process. Now, if the second argument begins with a non-digit,
3576 it will be treated as a corefile. If it begins with a digit,
3577 GDB will attempt to attach it as a process, and if no such process
3578 is found, will then attempt to open it as a corefile.
3580 * Changes in ARM configurations.
3582 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3583 configuration is fully multi-arch.
3585 * New native configurations
3587 ARM NetBSD arm*-*-netbsd*
3588 x86 OpenBSD i[3456]86-*-openbsd*
3589 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3590 Sparc64 running FreeBSD sparc64-*-freebsd*
3594 Sanyo XStormy16 xstormy16-elf
3596 * OBSOLETE configurations and files
3598 Configurations that have been declared obsolete in this release have
3599 been commented out. Unless there is activity to revive these
3600 configurations, the next release of GDB will have their sources
3601 permanently REMOVED.
3603 AMD 29k family via UDI a29k-amd-udi, udi29k
3604 A29K VxWorks a29k-*-vxworks
3605 AMD 29000 embedded, using EBMON a29k-none-none
3606 AMD 29000 embedded with COFF a29k-none-coff
3607 AMD 29000 embedded with a.out a29k-none-aout
3609 testsuite/gdb.hp/gdb.threads-hp/ directory
3611 * REMOVED configurations and files
3613 TI TMS320C80 tic80-*-*
3615 PowerPC Solaris powerpcle-*-solaris*
3616 PowerPC Windows NT powerpcle-*-cygwin32
3617 PowerPC Netware powerpc-*-netware*
3618 Harris/CXUX m88k m88*-harris-cxux*
3619 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3620 ns32k-utek-sysv* ns32k-utek-*
3621 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3622 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3623 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3624 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3625 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3627 * Changes to command line processing
3629 The new `--args' feature can be used to specify command-line arguments
3630 for the inferior from gdb's command line.
3632 * Changes to key bindings
3634 There is a new `operate-and-get-next' function bound to `C-o'.
3636 *** Changes in GDB 5.1.1
3638 Fix compile problem on DJGPP.
3640 Fix a problem with floating-point registers on the i386 being
3643 Fix to stop GDB crashing on .debug_str debug info.
3645 Numerous documentation fixes.
3647 Numerous testsuite fixes.
3649 *** Changes in GDB 5.1:
3651 * New native configurations
3653 Alpha FreeBSD alpha*-*-freebsd*
3654 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3655 MIPS GNU/Linux mips*-*-linux*
3656 MIPS SGI Irix 6.x mips*-sgi-irix6*
3657 ia64 AIX ia64-*-aix*
3658 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3662 Motorola 68HC11 and 68HC12 m68hc11-elf
3664 UltraSparc running GNU/Linux sparc64-*-linux*
3666 * OBSOLETE configurations and files
3668 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3669 Harris/CXUX m88k m88*-harris-cxux*
3670 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3671 ns32k-utek-sysv* ns32k-utek-*
3672 TI TMS320C80 tic80-*-*
3674 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3675 PowerPC Solaris powerpcle-*-solaris*
3676 PowerPC Windows NT powerpcle-*-cygwin32
3677 PowerPC Netware powerpc-*-netware*
3678 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3679 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3680 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3681 Apple Macintosh (MPW) host N/A
3683 stuff.c (Program to stuff files into a specially prepared space in kdb)
3684 kdb-start.c (Main loop for the standalone kernel debugger)
3686 Configurations that have been declared obsolete in this release have
3687 been commented out. Unless there is activity to revive these
3688 configurations, the next release of GDB will have their sources
3689 permanently REMOVED.
3691 * REMOVED configurations and files
3693 Altos 3068 m68*-altos-*
3694 Convex c1-*-*, c2-*-*
3696 ARM RISCix arm-*-* (as host)
3700 * GDB has been converted to ISO C.
3702 GDB's source code has been converted to ISO C. In particular, the
3703 sources are fully protoized, and rely on standard headers being
3708 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3710 * The MI enabled by default.
3712 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3713 revised and enabled by default. Packages which use GDB as a debugging
3714 engine behind a UI or another front end are encouraged to switch to
3715 using the GDB/MI interface, instead of the old annotations interface
3716 which is now deprecated.
3718 * Support for debugging Pascal programs.
3720 GDB now includes support for debugging Pascal programs. The following
3721 main features are supported:
3723 - Pascal-specific data types such as sets;
3725 - automatic recognition of Pascal sources based on file-name
3728 - Pascal-style display of data types, variables, and functions;
3730 - a Pascal expression parser.
3732 However, some important features are not yet supported.
3734 - Pascal string operations are not supported at all;
3736 - there are some problems with boolean types;
3738 - Pascal type hexadecimal constants are not supported
3739 because they conflict with the internal variables format;
3741 - support for Pascal objects and classes is not full yet;
3743 - unlike Pascal, GDB is case-sensitive for symbol names.
3745 * Changes in completion.
3747 Commands such as `shell', `run' and `set args', which pass arguments
3748 to inferior programs, now complete on file names, similar to what
3749 users expect at the shell prompt.
3751 Commands which accept locations, such as `disassemble', `print',
3752 `breakpoint', `until', etc. now complete on filenames as well as
3753 program symbols. Thus, if you type "break foob TAB", and the source
3754 files linked into the programs include `foobar.c', that file name will
3755 be one of the candidates for completion. However, file names are not
3756 considered for completion after you typed a colon that delimits a file
3757 name from a name of a function in that file, as in "break foo.c:bar".
3759 `set demangle-style' completes on available demangling styles.
3761 * New platform-independent commands:
3763 It is now possible to define a post-hook for a command as well as a
3764 hook that runs before the command. For more details, see the
3765 documentation of `hookpost' in the GDB manual.
3767 * Changes in GNU/Linux native debugging.
3769 Support for debugging multi-threaded programs has been completely
3770 revised for all platforms except m68k and sparc. You can now debug as
3771 many threads as your system allows you to have.
3773 Attach/detach is supported for multi-threaded programs.
3775 Support for SSE registers was added for x86. This doesn't work for
3776 multi-threaded programs though.
3778 * Changes in MIPS configurations.
3780 Multi-arch support is enabled for all MIPS configurations.
3782 GDB can now be built as native debugger on SGI Irix 6.x systems for
3783 debugging n32 executables. (Debugging 64-bit executables is not yet
3786 * Unified support for hardware watchpoints in all x86 configurations.
3788 Most (if not all) native x86 configurations support hardware-assisted
3789 breakpoints and watchpoints in a unified manner. This support
3790 implements debug register sharing between watchpoints, which allows to
3791 put a virtually infinite number of watchpoints on the same address,
3792 and also supports watching regions up to 16 bytes with several debug
3795 The new maintenance command `maintenance show-debug-regs' toggles
3796 debugging print-outs in functions that insert, remove, and test
3797 watchpoints and hardware breakpoints.
3799 * Changes in the DJGPP native configuration.
3801 New command ``info dos sysinfo'' displays assorted information about
3802 the CPU, OS, memory, and DPMI server.
3804 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3805 display information about segment descriptors stored in GDT, LDT, and
3808 New commands ``info dos pde'' and ``info dos pte'' display entries
3809 from Page Directory and Page Tables (for now works with CWSDPMI only).
3810 New command ``info dos address-pte'' displays the Page Table entry for
3811 a given linear address.
3813 GDB can now pass command lines longer than 126 characters to the
3814 program being debugged (requires an update to the libdbg.a library
3815 which is part of the DJGPP development kit).
3817 DWARF2 debug info is now supported.
3819 It is now possible to `step' and `next' through calls to `longjmp'.
3821 * Changes in documentation.
3823 All GDB documentation was converted to GFDL, the GNU Free
3824 Documentation License.
3826 Tracepoints-related commands are now fully documented in the GDB
3829 TUI, the Text-mode User Interface, is now documented in the manual.
3831 Tracepoints-related commands are now fully documented in the GDB
3834 The "GDB Internals" manual now has an index. It also includes
3835 documentation of `ui_out' functions, GDB coding standards, x86
3836 hardware watchpoints, and memory region attributes.
3838 * GDB's version number moved to ``version.in''
3840 The Makefile variable VERSION has been replaced by the file
3841 ``version.in''. People creating GDB distributions should update the
3842 contents of this file.
3846 GUD support is now a standard part of the EMACS distribution.
3848 *** Changes in GDB 5.0:
3850 * Improved support for debugging FP programs on x86 targets
3852 Unified and much-improved support for debugging floating-point
3853 programs on all x86 targets. In particular, ``info float'' now
3854 displays the FP registers in the same format on all x86 targets, with
3855 greater level of detail.
3857 * Improvements and bugfixes in hardware-assisted watchpoints
3859 It is now possible to watch array elements, struct members, and
3860 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3861 on x86 targets no longer erroneously trigger when the address is
3864 * Improvements in the native DJGPP version of GDB
3866 The distribution now includes all the scripts and auxiliary files
3867 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3868 machines ``out of the box''.
3870 The DJGPP version can now debug programs that use signals. It is
3871 possible to catch signals that happened in the debuggee, deliver
3872 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3873 would kill the program being debugged.) Programs that hook hardware
3874 interrupts (keyboard, timer, etc.) can also be debugged.
3876 It is now possible to debug DJGPP programs that redirect their
3877 standard handles or switch them to raw (as opposed to cooked) mode, or
3878 even close them. The command ``run < foo > bar'' works as expected,
3879 and ``info terminal'' reports useful information about the debuggee's
3880 terminal, including raw/cooked mode, redirection, etc.
3882 The DJGPP version now uses termios functions for console I/O, which
3883 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3886 DOS-style file names with drive letters are now fully supported by
3889 It is now possible to debug DJGPP programs that switch their working
3890 directory. It is also possible to rerun the debuggee any number of
3891 times without restarting GDB; thus, you can use the same setup,
3892 breakpoints, etc. for many debugging sessions.
3894 * New native configurations
3896 ARM GNU/Linux arm*-*-linux*
3897 PowerPC GNU/Linux powerpc-*-linux*
3901 Motorola MCore mcore-*-*
3902 x86 VxWorks i[3456]86-*-vxworks*
3903 PowerPC VxWorks powerpc-*-vxworks*
3904 TI TMS320C80 tic80-*-*
3906 * OBSOLETE configurations
3908 Altos 3068 m68*-altos-*
3909 Convex c1-*-*, c2-*-*
3911 ARM RISCix arm-*-* (as host)
3914 Configurations that have been declared obsolete will be commented out,
3915 but the code will be left in place. If there is no activity to revive
3916 these configurations before the next release of GDB, the sources will
3917 be permanently REMOVED.
3919 * Gould support removed
3921 Support for the Gould PowerNode and NP1 has been removed.
3923 * New features for SVR4
3925 On SVR4 native platforms (such as Solaris), if you attach to a process
3926 without first loading a symbol file, GDB will now attempt to locate and
3927 load symbols from the running process's executable file.
3929 * Many C++ enhancements
3931 C++ support has been greatly improved. Overload resolution now works properly
3932 in almost all cases. RTTI support is on the way.
3934 * Remote targets can connect to a sub-program
3936 A popen(3) style serial-device has been added. This device starts a
3937 sub-process (such as a stand-alone simulator) and then communicates
3938 with that. The sub-program to run is specified using the syntax
3939 ``|<program> <args>'' vis:
3941 (gdb) set remotedebug 1
3942 (gdb) target extended-remote |mn10300-elf-sim program-args
3944 * MIPS 64 remote protocol
3946 A long standing bug in the mips64 remote protocol where by GDB
3947 expected certain 32 bit registers (ex SR) to be transfered as 32
3948 instead of 64 bits has been fixed.
3950 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3951 added to provide backward compatibility with older versions of GDB.
3953 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3955 The command ``set remotebinarydownload'' command has been replaced by
3956 ``set remote X-packet''. Other commands in ``set remote'' family
3957 include ``set remote P-packet''.
3959 * Breakpoint commands accept ranges.
3961 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3962 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3963 ``tracepoint passcount'' also accepts a range of tracepoints.
3965 * ``apropos'' command added.
3967 The ``apropos'' command searches through command names and
3968 documentation strings, printing out matches, making it much easier to
3969 try to find a command that does what you are looking for.
3973 A new machine oriented interface (MI) has been added to GDB. This
3974 interface is designed for debug environments running GDB as a separate
3975 process. This is part of the long term libGDB project. See the
3976 "GDB/MI" chapter of the GDB manual for further information. It can be
3977 enabled by configuring with:
3979 .../configure --enable-gdbmi
3981 *** Changes in GDB-4.18:
3983 * New native configurations
3985 HP-UX 10.20 hppa*-*-hpux10.20
3986 HP-UX 11.x hppa*-*-hpux11.0*
3987 M68K GNU/Linux m68*-*-linux*
3991 Fujitsu FR30 fr30-*-elf*
3992 Intel StrongARM strongarm-*-*
3993 Mitsubishi D30V d30v-*-*
3995 * OBSOLETE configurations
3997 Gould PowerNode, NP1 np1-*-*, pn-*-*
3999 Configurations that have been declared obsolete will be commented out,
4000 but the code will be left in place. If there is no activity to revive
4001 these configurations before the next release of GDB, the sources will
4002 be permanently REMOVED.
4006 As a compatibility experiment, GDB's source files buildsym.h and
4007 buildsym.c have been converted to pure standard C, no longer
4008 containing any K&R compatibility code. We believe that all systems in
4009 use today either come with a standard C compiler, or have a GCC port
4010 available. If this is not true, please report the affected
4011 configuration to bug-gdb@gnu.org immediately. See the README file for
4012 information about getting a standard C compiler if you don't have one
4017 GDB now uses readline 2.2.
4019 * set extension-language
4021 You can now control the mapping between filename extensions and source
4022 languages by using the `set extension-language' command. For instance,
4023 you can ask GDB to treat .c files as C++ by saying
4024 set extension-language .c c++
4025 The command `info extensions' lists all of the recognized extensions
4026 and their associated languages.
4028 * Setting processor type for PowerPC and RS/6000
4030 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4031 you can use the `set processor' command to specify what variant of the
4032 PowerPC family you are debugging. The command
4036 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4037 following PowerPC and RS6000 variants:
4039 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4040 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4042 403GC IBM PowerPC 403GC
4043 505 Motorola PowerPC 505
4044 860 Motorola PowerPC 860 or 850
4045 601 Motorola PowerPC 601
4046 602 Motorola PowerPC 602
4047 603 Motorola/IBM PowerPC 603 or 603e
4048 604 Motorola PowerPC 604 or 604e
4049 750 Motorola/IBM PowerPC 750 or 750
4051 At the moment, this command just tells GDB what to name the
4052 special-purpose processor registers. Since almost all the affected
4053 registers are inaccessible to user-level programs, this command is
4054 only useful for remote debugging in its present form.
4058 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4059 more extensive support for HP-UX. Added features include shared
4060 library support, kernel threads and hardware watchpoints for 11.00,
4061 support for HP's ANSI C and C++ compilers, and a compatibility mode
4062 for xdb and dbx commands.
4066 HP's donation includes the new concept of catchpoints, which is a
4067 generalization of the old catch command. On HP-UX, it is now possible
4068 to catch exec, fork, and vfork, as well as library loading.
4070 This means that the existing catch command has changed; its first
4071 argument now specifies the type of catch to be set up. See the
4072 output of "help catch" for a list of catchpoint types.
4074 * Debugging across forks
4076 On HP-UX, you can choose which process to debug when a fork() happens
4081 HP has donated a curses-based terminal user interface (TUI). To get
4082 it, build with --enable-tui. Although this can be enabled for any
4083 configuration, at present it only works for native HP debugging.
4085 * GDB remote protocol additions
4087 A new protocol packet 'X' that writes binary data is now available.
4088 Default behavior is to try 'X', then drop back to 'M' if the stub
4089 fails to respond. The settable variable `remotebinarydownload'
4090 allows explicit control over the use of 'X'.
4092 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4093 full 64-bit address. The command
4095 set remoteaddresssize 32
4097 can be used to revert to the old behaviour. For existing remote stubs
4098 the change should not be noticed, as the additional address information
4101 In order to assist in debugging stubs, you may use the maintenance
4102 command `packet' to send any text string to the stub. For instance,
4104 maint packet heythere
4106 sends the packet "$heythere#<checksum>". Note that it is very easy to
4107 disrupt a debugging session by sending the wrong packet at the wrong
4110 The compare-sections command allows you to compare section data on the
4111 target to what is in the executable file without uploading or
4112 downloading, by comparing CRC checksums.
4114 * Tracing can collect general expressions
4116 You may now collect general expressions at tracepoints. This requires
4117 further additions to the target-side stub; see tracepoint.c and
4118 doc/agentexpr.texi for further details.
4120 * mask-address variable for Mips
4122 For Mips targets, you may control the zeroing of the upper 32 bits of
4123 a 64-bit address by entering `set mask-address on'. This is mainly
4124 of interest to users of embedded R4xxx and R5xxx processors.
4126 * Higher serial baud rates
4128 GDB's serial code now allows you to specify baud rates 57600, 115200,
4129 230400, and 460800 baud. (Note that your host system may not be able
4130 to achieve all of these rates.)
4134 The i960 configuration now includes an initial implementation of a
4135 builtin simulator, contributed by Jim Wilson.
4138 *** Changes in GDB-4.17:
4140 * New native configurations
4142 Alpha GNU/Linux alpha*-*-linux*
4143 Unixware 2.x i[3456]86-unixware2*
4144 Irix 6.x mips*-sgi-irix6*
4145 PowerPC GNU/Linux powerpc-*-linux*
4146 PowerPC Solaris powerpcle-*-solaris*
4147 Sparc GNU/Linux sparc-*-linux*
4148 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4152 Argonaut Risc Chip (ARC) arc-*-*
4153 Hitachi H8/300S h8300*-*-*
4154 Matsushita MN10200 w/simulator mn10200-*-*
4155 Matsushita MN10300 w/simulator mn10300-*-*
4156 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4157 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4158 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4159 Mitsubishi D10V w/simulator d10v-*-*
4160 Mitsubishi M32R/D w/simulator m32r-*-elf*
4161 Tsqware Sparclet sparclet-*-*
4162 NEC V850 w/simulator v850-*-*
4164 * New debugging protocols
4166 ARM with RDI protocol arm*-*-*
4167 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4168 DDB and LSI variants of PMON protocol mips*-*-*
4169 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4170 PowerPC with SDS protocol powerpc{,le}-*-eabi
4171 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4175 All configurations can now understand and use the DWARF 2 debugging
4176 format. The choice is automatic, if the symbol file contains DWARF 2
4181 GDB now includes basic Java language support. This support is
4182 only useful with Java compilers that produce native machine code.
4184 * solib-absolute-prefix and solib-search-path
4186 For SunOS and SVR4 shared libraries, you may now set the prefix for
4187 loading absolute shared library symbol files, and the search path for
4188 locating non-absolute shared library symbol files.
4190 * Live range splitting
4192 GDB can now effectively debug code for which GCC has performed live
4193 range splitting as part of its optimization. See gdb/doc/LRS for
4194 more details on the expected format of the stabs information.
4198 GDB's support for the GNU Hurd, including thread debugging, has been
4199 updated to work with current versions of the Hurd.
4203 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4204 instruction set. ARM GDB automatically detects when Thumb
4205 instructions are in use, and adjusts disassembly and backtracing
4210 GDB's MIPS target configurations now handle the MIP16 16-bit
4215 GDB now includes support for overlays; if an executable has been
4216 linked such that multiple sections are based at the same address, GDB
4217 will decide which section to use for symbolic info. You can choose to
4218 control the decision manually, using overlay commands, or implement
4219 additional target-side support and use "overlay load-target" to bring
4220 in the overlay mapping. Do "help overlay" for more detail.
4224 The command "info symbol <address>" displays information about
4225 the symbol at the specified address.
4229 The standard remote protocol now includes an extension that allows
4230 asynchronous collection and display of trace data. This requires
4231 extensive support in the target-side debugging stub. Tracing mode
4232 includes a new interaction mode in GDB and new commands: see the
4233 file tracepoint.c for more details.
4237 Configurations for embedded MIPS now include a simulator contributed
4238 by Cygnus Solutions. The simulator supports the instruction sets
4239 of most MIPS variants.
4243 Sparc configurations may now include the ERC32 simulator contributed
4244 by the European Space Agency. The simulator is not built into
4245 Sparc targets by default; configure with --enable-sim to include it.
4249 For target configurations that may include multiple variants of a
4250 basic architecture (such as MIPS and SH), you may now set the
4251 architecture explicitly. "set arch" sets, "info arch" lists
4252 the possible architectures.
4254 *** Changes in GDB-4.16:
4256 * New native configurations
4258 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4259 M68K NetBSD m68k-*-netbsd*
4260 PowerPC AIX 4.x powerpc-*-aix*
4261 PowerPC MacOS powerpc-*-macos*
4262 PowerPC Windows NT powerpcle-*-cygwin32
4263 RS/6000 AIX 4.x rs6000-*-aix4*
4267 ARM with RDP protocol arm-*-*
4268 I960 with MON960 i960-*-coff
4269 MIPS VxWorks mips*-*-vxworks*
4270 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4271 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4273 Matra Sparclet sparclet-*-*
4277 The powerpc-eabi configuration now includes the PSIM simulator,
4278 contributed by Andrew Cagney, with assistance from Mike Meissner.
4279 PSIM is a very elaborate model of the PowerPC, including not only
4280 basic instruction set execution, but also details of execution unit
4281 performance and I/O hardware. See sim/ppc/README for more details.
4285 GDB now works with Solaris 2.5.
4287 * Windows 95/NT native
4289 GDB will now work as a native debugger on Windows 95 and Windows NT.
4290 To build it from source, you must use the "gnu-win32" environment,
4291 which uses a DLL to emulate enough of Unix to run the GNU tools.
4292 Further information, binaries, and sources are available at
4293 ftp.cygnus.com, under pub/gnu-win32.
4295 * dont-repeat command
4297 If a user-defined command includes the command `dont-repeat', then the
4298 command will not be repeated if the user just types return. This is
4299 useful if the command is time-consuming to run, so that accidental
4300 extra keystrokes don't run the same command many times.
4302 * Send break instead of ^C
4304 The standard remote protocol now includes an option to send a break
4305 rather than a ^C to the target in order to interrupt it. By default,
4306 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4308 * Remote protocol timeout
4310 The standard remote protocol includes a new variable `remotetimeout'
4311 that allows you to set the number of seconds before GDB gives up trying
4312 to read from the target. The default value is 2.
4314 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4316 By default GDB will automatically keep track of objects as they are
4317 loaded and unloaded by the dynamic linker. By using the command `set
4318 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4319 when shared library events occur, thus allowing you to set breakpoints
4320 in shared libraries which are explicitly loaded by the inferior.
4322 Note this feature does not work on hpux8. On hpux9 you must link
4323 /usr/lib/end.o into your program. This feature should work
4324 automatically on hpux10.
4326 * Irix 5.x hardware watchpoint support
4328 Irix 5 configurations now support the use of hardware watchpoints.
4330 * Mips protocol "SYN garbage limit"
4332 When debugging a Mips target using the `target mips' protocol, you
4333 may set the number of characters that GDB will ignore by setting
4334 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4335 every character. The default value is 1050.
4337 * Recording and replaying remote debug sessions
4339 If you set `remotelogfile' to the name of a file, gdb will write to it
4340 a recording of a remote debug session. This recording may then be
4341 replayed back to gdb using "gdbreplay". See gdbserver/README for
4342 details. This is useful when you have a problem with GDB while doing
4343 remote debugging; you can make a recording of the session and send it
4344 to someone else, who can then recreate the problem.
4346 * Speedups for remote debugging
4348 GDB includes speedups for downloading and stepping MIPS systems using
4349 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4350 and more efficient S-record downloading.
4352 * Memory use reductions and statistics collection
4354 GDB now uses less memory and reports statistics about memory usage.
4355 Try the `maint print statistics' command, for example.
4357 *** Changes in GDB-4.15:
4359 * Psymtabs for XCOFF
4361 The symbol reader for AIX GDB now uses partial symbol tables. This
4362 can greatly improve startup time, especially for large executables.
4364 * Remote targets use caching
4366 Remote targets now use a data cache to speed up communication with the
4367 remote side. The data cache could lead to incorrect results because
4368 it doesn't know about volatile variables, thus making it impossible to
4369 debug targets which use memory mapped I/O devices. `set remotecache
4370 off' turns the the data cache off.
4372 * Remote targets may have threads
4374 The standard remote protocol now includes support for multiple threads
4375 in the target system, using new protocol commands 'H' and 'T'. See
4376 gdb/remote.c for details.
4380 If GDB is configured with `--enable-netrom', then it will include
4381 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4382 acts as though it is a bank of ROM on the target board, but you can
4383 write into it over the network. GDB's support consists only of
4384 support for fast loading into the emulated ROM; to debug, you must use
4385 another protocol, such as standard remote protocol. The usual
4386 sequence is something like
4388 target nrom <netrom-hostname>
4390 target remote <netrom-hostname>:1235
4394 GDB now includes support for the Apple Macintosh, as a host only. It
4395 may be run as either an MPW tool or as a standalone application, and
4396 it can debug through the serial port. All the usual GDB commands are
4397 available, but to the target command, you must supply "serial" as the
4398 device type instead of "/dev/ttyXX". See mpw-README in the main
4399 directory for more information on how to build. The MPW configuration
4400 scripts */mpw-config.in support only a few targets, and only the
4401 mips-idt-ecoff target has been tested.
4405 GDB configuration now uses autoconf. This is not user-visible,
4406 but does simplify configuration and building.
4410 GDB now supports hpux10.
4412 *** Changes in GDB-4.14:
4414 * New native configurations
4416 x86 FreeBSD i[345]86-*-freebsd
4417 x86 NetBSD i[345]86-*-netbsd
4418 NS32k NetBSD ns32k-*-netbsd
4419 Sparc NetBSD sparc-*-netbsd
4423 A29K VxWorks a29k-*-vxworks
4424 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4425 CPU32 EST-300 emulator m68*-*-est*
4426 PowerPC ELF powerpc-*-elf
4429 * Alpha OSF/1 support for procfs
4431 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4432 possible to attach to running processes. As the mounting of the /proc
4433 filesystem is optional on the Alpha, GDB automatically determines
4434 the availability of /proc during startup. This can lead to problems
4435 if /proc is unmounted after GDB has been started.
4437 * Arguments to user-defined commands
4439 User commands may accept up to 10 arguments separated by whitespace.
4440 Arguments are accessed within the user command via $arg0..$arg9. A
4443 print $arg0 + $arg1 + $arg2
4445 To execute the command use:
4448 Defines the command "adder" which prints the sum of its three arguments.
4449 Note the arguments are text substitutions, so they may reference variables,
4450 use complex expressions, or even perform inferior function calls.
4452 * New `if' and `while' commands
4454 This makes it possible to write more sophisticated user-defined
4455 commands. Both commands take a single argument, which is the
4456 expression to evaluate, and must be followed by the commands to
4457 execute, one per line, if the expression is nonzero, the list being
4458 terminated by the word `end'. The `if' command list may include an
4459 `else' word, which causes the following commands to be executed only
4460 if the expression is zero.
4462 * Fortran source language mode
4464 GDB now includes partial support for Fortran 77. It will recognize
4465 Fortran programs and can evaluate a subset of Fortran expressions, but
4466 variables and functions may not be handled correctly. GDB will work
4467 with G77, but does not yet know much about symbols emitted by other
4470 * Better HPUX support
4472 Most debugging facilities now work on dynamic executables for HPPAs
4473 running hpux9 or later. You can attach to running dynamically linked
4474 processes, but by default the dynamic libraries will be read-only, so
4475 for instance you won't be able to put breakpoints in them. To change
4476 that behavior do the following before running the program:
4482 This will cause the libraries to be mapped private and read-write.
4483 To revert to the normal behavior, do this:
4489 You cannot set breakpoints or examine data in the library until after
4490 the library is loaded if the function/data symbols do not have
4493 GDB can now also read debug symbols produced by the HP C compiler on
4494 HPPAs (sorry, no C++, Fortran or 68k support).
4496 * Target byte order now dynamically selectable
4498 You can choose which byte order to use with a target system, via the
4499 commands "set endian big" and "set endian little", and you can see the
4500 current setting by using "show endian". You can also give the command
4501 "set endian auto", in which case GDB will use the byte order
4502 associated with the executable. Currently, only embedded MIPS
4503 configurations support dynamic selection of target byte order.
4505 * New DOS host serial code
4507 This version uses DPMI interrupts to handle buffered I/O, so you
4508 no longer need to run asynctsr when debugging boards connected to
4511 *** Changes in GDB-4.13:
4513 * New "complete" command
4515 This lists all the possible completions for the rest of the line, if it
4516 were to be given as a command itself. This is intended for use by emacs.
4518 * Trailing space optional in prompt
4520 "set prompt" no longer adds a space for you after the prompt you set. This
4521 allows you to set a prompt which ends in a space or one that does not.
4523 * Breakpoint hit counts
4525 "info break" now displays a count of the number of times the breakpoint
4526 has been hit. This is especially useful in conjunction with "ignore"; you
4527 can ignore a large number of breakpoint hits, look at the breakpoint info
4528 to see how many times the breakpoint was hit, then run again, ignoring one
4529 less than that number, and this will get you quickly to the last hit of
4532 * Ability to stop printing at NULL character
4534 "set print null-stop" will cause GDB to stop printing the characters of
4535 an array when the first NULL is encountered. This is useful when large
4536 arrays actually contain only short strings.
4538 * Shared library breakpoints
4540 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4541 breakpoints in shared libraries before the executable is run.
4543 * Hardware watchpoints
4545 There is a new hardware breakpoint for the watch command for sparclite
4546 targets. See gdb/sparclite/hw_breakpoint.note.
4548 Hardware watchpoints are also now supported under GNU/Linux.
4552 Annotations have been added. These are for use with graphical interfaces,
4553 and are still experimental. Currently only gdba.el uses these.
4555 * Improved Irix 5 support
4557 GDB now works properly with Irix 5.2.
4559 * Improved HPPA support
4561 GDB now works properly with the latest GCC and GAS.
4563 * New native configurations
4565 Sequent PTX4 i[34]86-sequent-ptx4
4566 HPPA running OSF/1 hppa*-*-osf*
4567 Atari TT running SVR4 m68*-*-sysv4*
4568 RS/6000 LynxOS rs6000-*-lynxos*
4572 OS/9000 i[34]86-*-os9k
4573 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4576 * Hitachi SH7000 and E7000-PC ICE support
4578 There is now support for communicating with the Hitachi E7000-PC ICE.
4579 This is available automatically when GDB is configured for the SH.
4583 As usual, a variety of small fixes and improvements, both generic
4584 and configuration-specific. See the ChangeLog for more detail.
4586 *** Changes in GDB-4.12:
4588 * Irix 5 is now supported
4592 GDB-4.12 on the HPPA has a number of changes which make it unable
4593 to debug the output from the currently released versions of GCC and
4594 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4595 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4596 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4599 *** Changes in GDB-4.11:
4601 * User visible changes:
4605 The "set remotedebug" option is now consistent between the mips remote
4606 target, remote targets using the gdb-specific protocol, UDI (AMD's
4607 debug protocol for the 29k) and the 88k bug monitor. It is now an
4608 integer specifying a debug level (normally 0 or 1, but 2 means more
4609 debugging info for the mips target).
4611 * DEC Alpha native support
4613 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4614 debug info, but GDB works fairly well with the DEC compiler and should
4615 work with a future GCC release. See the README file for a few
4616 Alpha-specific notes.
4618 * Preliminary thread implementation
4620 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4622 * LynxOS native and target support for 386
4624 This release has been hosted on LynxOS 2.2, and also can be configured
4625 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4628 * Improvements in C++ mangling/demangling.
4630 This release has much better g++ debugging, specifically in name
4631 mangling/demangling, virtual function calls, print virtual table,
4632 call methods, ...etc.
4634 *** Changes in GDB-4.10:
4636 * User visible changes:
4638 Remote debugging using the GDB-specific (`target remote') protocol now
4639 supports the `load' command. This is only useful if you have some
4640 other way of getting the stub to the target system, and you can put it
4641 somewhere in memory where it won't get clobbered by the download.
4643 Filename completion now works.
4645 When run under emacs mode, the "info line" command now causes the
4646 arrow to point to the line specified. Also, "info line" prints
4647 addresses in symbolic form (as well as hex).
4649 All vxworks based targets now support a user settable option, called
4650 vxworks-timeout. This option represents the number of seconds gdb
4651 should wait for responses to rpc's. You might want to use this if
4652 your vxworks target is, perhaps, a slow software simulator or happens
4653 to be on the far side of a thin network line.
4657 This release contains support for using a DEC alpha as a GDB host for
4658 cross debugging. Native alpha debugging is not supported yet.
4661 *** Changes in GDB-4.9:
4665 This is the first GDB release which is accompanied by a matching testsuite.
4666 The testsuite requires installation of dejagnu, which should be available
4667 via ftp from most sites that carry GNU software.
4671 'Cfront' style demangling has had its name changed to 'ARM' style, to
4672 emphasize that it was written from the specifications in the C++ Annotated
4673 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4674 disclaimers, it still generated too much confusion with users attempting to
4675 use gdb with AT&T cfront.
4679 GDB now uses a standard remote interface to a simulator library.
4680 So far, the library contains simulators for the Zilog Z8001/2, the
4681 Hitachi H8/300, H8/500 and Super-H.
4683 * New targets supported
4685 H8/300 simulator h8300-hitachi-hms or h8300hms
4686 H8/500 simulator h8500-hitachi-hms or h8500hms
4687 SH simulator sh-hitachi-hms or sh
4688 Z8000 simulator z8k-zilog-none or z8ksim
4689 IDT MIPS board over serial line mips-idt-ecoff
4691 Cross-debugging to GO32 targets is supported. It requires a custom
4692 version of the i386-stub.c module which is integrated with the
4693 GO32 memory extender.
4695 * New remote protocols
4697 MIPS remote debugging protocol.
4699 * New source languages supported
4701 This version includes preliminary support for Chill, a Pascal like language
4702 used by telecommunications companies. Chill support is also being integrated
4703 into the GNU compiler, but we don't know when it will be publically available.
4706 *** Changes in GDB-4.8:
4708 * HP Precision Architecture supported
4710 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4711 version of this support was available as a set of patches from the
4712 University of Utah. GDB does not support debugging of programs
4713 compiled with the HP compiler, because HP will not document their file
4714 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4715 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4717 Many problems in the preliminary version have been fixed.
4719 * Faster and better demangling
4721 We have improved template demangling and fixed numerous bugs in the GNU style
4722 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4723 character types (wchar_t) are now supported. Demangling of each symbol is now
4724 only done once, and is cached when the symbol table for a file is read in.
4725 This results in a small increase in memory usage for C programs, a moderate
4726 increase in memory usage for C++ programs, and a fantastic speedup in
4729 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4730 from the specifications in the Annotated Reference Manual, which AT&T's
4731 compiler does not actually implement.
4733 * G++ multiple inheritance compiler problem
4735 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4736 inheritance lattices was reworked to properly discover ambiguities. We
4737 recently found an example which causes this new algorithm to fail in a
4738 very subtle way, producing bad debug information for those classes.
4739 The file 'gcc.patch' (in this directory) can be applied to gcc to
4740 circumvent the problem. A future GCC release will contain a complete
4743 The previous G++ debug info problem (mentioned below for the gdb-4.7
4744 release) is fixed in gcc version 2.3.2.
4746 * Improved configure script
4748 The `configure' script will now attempt to guess your system type if
4749 you don't supply a host system type. The old scheme of supplying a
4750 host system triplet is preferable over using this. All the magic is
4751 done in the new `config.guess' script. Examine it for details.
4753 We have also brought our configure script much more in line with the FSF's
4754 version. It now supports the --with-xxx options. In particular,
4755 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4756 The resulting GDB will not be able to read arbitrary object file formats --
4757 only the format ``expected'' to be used on the configured target system.
4758 We hope to make this the default in a future release.
4760 * Documentation improvements
4762 There's new internal documentation on how to modify GDB, and how to
4763 produce clean changes to the code. We implore people to read it
4764 before submitting changes.
4766 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4767 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4768 `info' files are also provided. To build `info' files from scratch,
4769 you will need the latest `makeinfo' release, which will be available in
4770 a future texinfo-X.Y release.
4772 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4773 We're not sure exactly which versions have this problem, but it has
4774 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4775 or better. If that isn't possible, there is a patch in
4776 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4777 around this problem.
4781 GDB now supports array constants that can be used in expressions typed in by
4782 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4783 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4786 The new directory `gdb/sparclite' contains a program that demonstrates
4787 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4789 * New native hosts supported
4791 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4792 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4794 * New targets supported
4796 AMD 29k family via UDI a29k-amd-udi or udi29k
4798 * New file formats supported
4800 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4801 HPUX core files, and SCO 3.2v2 core files.
4805 Attaching to processes now works again; thanks for the many bug reports.
4807 We have also stomped on a bunch of core dumps caused by
4808 printf_filtered("%s") problems.
4810 We eliminated a copyright problem on the rpc and ptrace header files
4811 for VxWorks, which was discovered at the last minute during the 4.7
4812 release. You should now be able to build a VxWorks GDB.
4814 You can now interrupt gdb while an attached process is running. This
4815 will cause the attached process to stop, and give control back to GDB.
4817 We fixed problems caused by using too many file descriptors
4818 for reading symbols from object files and libraries. This was
4819 especially a problem for programs that used many (~100) shared
4822 The `step' command now only enters a subroutine if there is line number
4823 information for the subroutine. Otherwise it acts like the `next'
4824 command. Previously, `step' would enter subroutines if there was
4825 any debugging information about the routine. This avoids problems
4826 when using `cc -g1' on MIPS machines.
4828 * Internal improvements
4830 GDB's internal interfaces have been improved to make it easier to support
4831 debugging of multiple languages in the future.
4833 GDB now uses a common structure for symbol information internally.
4834 Minimal symbols (derived from linkage symbols in object files), partial
4835 symbols (from a quick scan of debug information), and full symbols
4836 contain a common subset of information, making it easier to write
4837 shared code that handles any of them.
4839 * New command line options
4841 We now accept --silent as an alias for --quiet.
4845 The memory-mapped-malloc library is now licensed under the GNU Library
4846 General Public License.
4848 *** Changes in GDB-4.7:
4850 * Host/native/target split
4852 GDB has had some major internal surgery to untangle the support for
4853 hosts and remote targets. Now, when you configure GDB for a remote
4854 target, it will no longer load in all of the support for debugging
4855 local programs on the host. When fully completed and tested, this will
4856 ensure that arbitrary host/target combinations are possible.
4858 The primary conceptual shift is to separate the non-portable code in
4859 GDB into three categories. Host specific code is required any time GDB
4860 is compiled on that host, regardless of the target. Target specific
4861 code relates to the peculiarities of the target, but can be compiled on
4862 any host. Native specific code is everything else: it can only be
4863 built when the host and target are the same system. Child process
4864 handling and core file support are two common `native' examples.
4866 GDB's use of /proc for controlling Unix child processes is now cleaner.
4867 It has been split out into a single module under the `target_ops' vector,
4868 plus two native-dependent functions for each system that uses /proc.
4870 * New hosts supported
4872 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4873 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4874 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4876 * New targets supported
4878 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4879 68030 and CPU32 m68030-*-*, m68332-*-*
4881 * New native hosts supported
4883 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4884 (386bsd is not well tested yet)
4885 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4887 * New file formats supported
4889 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4890 supports reading of `a.out.adobe' object files, which are an a.out
4891 format extended with minimal information about multiple sections.
4895 `show copying' is the same as the old `info copying'.
4896 `show warranty' is the same as `info warrantee'.
4897 These were renamed for consistency. The old commands continue to work.
4899 `info handle' is a new alias for `info signals'.
4901 You can now define pre-command hooks, which attach arbitrary command
4902 scripts to any command. The commands in the hook will be executed
4903 prior to the user's command. You can also create a hook which will be
4904 executed whenever the program stops. See gdb.texinfo.
4908 We now deal with Cfront style name mangling, and can even extract type
4909 info from mangled symbols. GDB can automatically figure out which
4910 symbol mangling style your C++ compiler uses.
4912 Calling of methods and virtual functions has been improved as well.
4916 The crash that occured when debugging Sun Ansi-C compiled binaries is
4917 fixed. This was due to mishandling of the extra N_SO stabs output
4920 We also finally got Ultrix 4.2 running in house, and fixed core file
4921 support, with help from a dozen people on the net.
4923 John M. Farrell discovered that the reason that single-stepping was so
4924 slow on all of the Mips based platforms (primarily SGI and DEC) was
4925 that we were trying to demangle and lookup a symbol used for internal
4926 purposes on every instruction that was being stepped through. Changing
4927 the name of that symbol so that it couldn't be mistaken for a C++
4928 mangled symbol sped things up a great deal.
4930 Rich Pixley sped up symbol lookups in general by getting much smarter
4931 about when C++ symbol mangling is necessary. This should make symbol
4932 completion (TAB on the command line) much faster. It's not as fast as
4933 we'd like, but it's significantly faster than gdb-4.6.
4937 A new user controllable variable 'call_scratch_address' can
4938 specify the location of a scratch area to be used when GDB
4939 calls a function in the target. This is necessary because the
4940 usual method of putting the scratch area on the stack does not work
4941 in systems that have separate instruction and data spaces.
4943 We integrated changes to support the 29k UDI (Universal Debugger
4944 Interface), but discovered at the last minute that we didn't have all
4945 of the appropriate copyright paperwork. We are working with AMD to
4946 resolve this, and hope to have it available soon.
4950 We have sped up the remote serial line protocol, especially for targets
4951 with lots of registers. It now supports a new `expedited status' ('T')
4952 message which can be used in place of the existing 'S' status message.
4953 This allows the remote stub to send only the registers that GDB
4954 needs to make a quick decision about single-stepping or conditional
4955 breakpoints, eliminating the need to fetch the entire register set for
4956 each instruction being stepped through.
4958 The GDB remote serial protocol now implements a write-through cache for
4959 registers, only re-reading the registers if the target has run.
4961 There is also a new remote serial stub for SPARC processors. You can
4962 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4963 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4964 processor with a serial port.
4968 Configure.in files have become much easier to read and modify. A new
4969 `table driven' format makes it more obvious what configurations are
4970 supported, and what files each one uses.
4974 There is a new opcodes library which will eventually contain all of the
4975 disassembly routines and opcode tables. At present, it only contains
4976 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4977 disassembler (binutils/objdump) to share these routines.
4979 The libiberty library is now copylefted under the GNU Library General
4980 Public License. This allows more liberal use, and was done so libg++
4981 can use it. This makes no difference to GDB, since the Library License
4982 grants all the rights from the General Public License.
4986 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4987 reference to the stabs symbol info used by the debugger. It is (as far
4988 as we know) the only published document on this fascinating topic. We
4989 encourage you to read it, compare it to the stabs information on your
4990 system, and send improvements on the document in general (to
4991 bug-gdb@prep.ai.mit.edu).
4993 And, of course, many bugs have been fixed.
4996 *** Changes in GDB-4.6:
4998 * Better support for C++ function names
5000 GDB now accepts as input the "demangled form" of C++ overloaded function
5001 names and member function names, and can do command completion on such names
5002 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5003 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5004 Make use of command completion, it is your friend.
5006 GDB also now accepts a variety of C++ mangled symbol formats. They are
5007 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5008 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5009 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5010 for the list of formats.
5012 * G++ symbol mangling problem
5014 Recent versions of gcc have a bug in how they emit debugging information for
5015 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5016 directory) can be applied to gcc to fix the problem. Alternatively, if you
5017 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5018 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5019 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5022 * New 'maintenance' command
5024 All of the commands related to hacking GDB internals have been moved out of
5025 the main command set, and now live behind the 'maintenance' command. This
5026 can also be abbreviated as 'mt'. The following changes were made:
5028 dump-me -> maintenance dump-me
5029 info all-breakpoints -> maintenance info breakpoints
5030 printmsyms -> maintenance print msyms
5031 printobjfiles -> maintenance print objfiles
5032 printpsyms -> maintenance print psymbols
5033 printsyms -> maintenance print symbols
5035 The following commands are new:
5037 maintenance demangle Call internal GDB demangler routine to
5038 demangle a C++ link name and prints the result.
5039 maintenance print type Print a type chain for a given symbol
5041 * Change to .gdbinit file processing
5043 We now read the $HOME/.gdbinit file before processing the argv arguments
5044 (e.g. reading symbol files or core files). This allows global parameters to
5045 be set, which will apply during the symbol reading. The ./.gdbinit is still
5046 read after argv processing.
5048 * New hosts supported
5050 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5052 GNU/Linux support i386-unknown-linux or linux
5054 We are also including code to support the HP/PA running BSD and HPUX. This
5055 is almost guaranteed not to work, as we didn't have time to test or build it
5056 for this release. We are including it so that the more adventurous (or
5057 masochistic) of you can play with it. We also had major problems with the
5058 fact that the compiler that we got from HP doesn't support the -g option.
5061 * New targets supported
5063 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5065 * More smarts about finding #include files
5067 GDB now remembers the compilation directory for all include files, and for
5068 all files from which C is generated (like yacc and lex sources). This
5069 greatly improves GDB's ability to find yacc/lex sources, and include files,
5070 especially if you are debugging your program from a directory different from
5071 the one that contains your sources.
5073 We also fixed a bug which caused difficulty with listing and setting
5074 breakpoints in include files which contain C code. (In the past, you had to
5075 try twice in order to list an include file that you hadn't looked at before.)
5077 * Interesting infernals change
5079 GDB now deals with arbitrary numbers of sections, where the symbols for each
5080 section must be relocated relative to that section's landing place in the
5081 target's address space. This work was needed to support ELF with embedded
5082 stabs used by Solaris-2.0.
5084 * Bug fixes (of course!)
5086 There have been loads of fixes for the following things:
5087 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5088 i960, stabs, DOS(GO32), procfs, etc...
5090 See the ChangeLog for details.
5092 *** Changes in GDB-4.5:
5094 * New machines supported (host and target)
5096 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5098 SGI Irix-4.x mips-sgi-irix4 or iris4
5100 * New malloc package
5102 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5103 Mmalloc is capable of handling mutiple heaps of memory. It is also
5104 capable of saving a heap to a file, and then mapping it back in later.
5105 This can be used to greatly speedup the startup of GDB by using a
5106 pre-parsed symbol table which lives in a mmalloc managed heap. For
5107 more details, please read mmalloc/mmalloc.texi.
5111 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5112 'help info proc' for details.
5114 * MIPS ecoff symbol table format
5116 The code that reads MIPS symbol table format is now supported on all hosts.
5117 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5120 * File name changes for MS-DOS
5122 Many files in the config directories have been renamed to make it easier to
5123 support GDB on MS-DOSe systems (which have very restrictive file name
5124 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5125 environment) is close to working but has some remaining problems. Note
5126 that debugging of DOS programs is not supported, due to limitations
5127 in the ``operating system'', but it can be used to host cross-debugging.
5129 * Cross byte order fixes
5131 Many fixes have been made to support cross debugging of Sparc and MIPS
5132 targets from hosts whose byte order differs.
5134 * New -mapped and -readnow options
5136 If memory-mapped files are available on your system through the 'mmap'
5137 system call, you can use the -mapped option on the `file' or
5138 `symbol-file' commands to cause GDB to write the symbols from your
5139 program into a reusable file. If the program you are debugging is
5140 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5141 Future GDB debugging sessions will notice the presence of this file,
5142 and will quickly map in symbol information from it, rather than reading
5143 the symbol table from the executable program. Using the '-mapped'
5144 option in a GDB `file' or `symbol-file' command has the same effect as
5145 starting GDB with the '-mapped' command-line option.
5147 You can cause GDB to read the entire symbol table immediately by using
5148 the '-readnow' option with any of the commands that load symbol table
5149 information (or on the GDB command line). This makes the command
5150 slower, but makes future operations faster.
5152 The -mapped and -readnow options are typically combined in order to
5153 build a `fred.syms' file that contains complete symbol information.
5154 A simple GDB invocation to do nothing but build a `.syms' file for future
5157 gdb -batch -nx -mapped -readnow programname
5159 The `.syms' file is specific to the host machine on which GDB is run.
5160 It holds an exact image of GDB's internal symbol table. It cannot be
5161 shared across multiple host platforms.
5163 * longjmp() handling
5165 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5166 siglongjmp() without losing control. This feature has not yet been ported to
5167 all systems. It currently works on many 386 platforms, all MIPS-based
5168 platforms (SGI, DECstation, etc), and Sun3/4.
5172 Preliminary work has been put in to support the new Solaris OS from Sun. At
5173 this time, it can control and debug processes, but it is not capable of
5178 As always, many many bug fixes. The major areas were with g++, and mipsread.
5179 People using the MIPS-based platforms should experience fewer mysterious
5180 crashes and trashed symbol tables.
5182 *** Changes in GDB-4.4:
5184 * New machines supported (host and target)
5186 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5188 BSD Reno on Vax vax-dec-bsd
5189 Ultrix on Vax vax-dec-ultrix
5191 * New machines supported (target)
5193 AMD 29000 embedded, using EBMON a29k-none-none
5197 GDB continues to improve its handling of C++. `References' work better.
5198 The demangler has also been improved, and now deals with symbols mangled as
5199 per the Annotated C++ Reference Guide.
5201 GDB also now handles `stabs' symbol information embedded in MIPS
5202 `ecoff' symbol tables. Since the ecoff format was not easily
5203 extensible to handle new languages such as C++, this appeared to be a
5204 good way to put C++ debugging info into MIPS binaries. This option
5205 will be supported in the GNU C compiler, version 2, when it is
5208 * New features for SVR4
5210 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5211 shared libraries. Debugging dynamically linked programs should present
5212 only minor differences from debugging statically linked programs.
5214 The `info proc' command will print out information about any process
5215 on an SVR4 system (including the one you are debugging). At the moment,
5216 it prints the address mappings of the process.
5218 If you bring up GDB on another SVR4 system, please send mail to
5219 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5221 * Better dynamic linking support in SunOS
5223 Reading symbols from shared libraries which contain debugging symbols
5224 now works properly. However, there remain issues such as automatic
5225 skipping of `transfer vector' code during function calls, which
5226 make it harder to debug code in a shared library, than to debug the
5227 same code linked statically.
5231 GDB is now using the latest `getopt' routines from the FSF. This
5232 version accepts the -- prefix for options with long names. GDB will
5233 continue to accept the old forms (-option and +option) as well.
5234 Various single letter abbreviations for options have been explicity
5235 added to the option table so that they won't get overshadowed in the
5236 future by other options that begin with the same letter.
5240 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5241 Many assorted bugs have been handled. Many more remain to be handled.
5242 See the various ChangeLog files (primarily in gdb and bfd) for details.
5245 *** Changes in GDB-4.3:
5247 * New machines supported (host and target)
5249 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5250 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5251 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5253 * Almost SCO Unix support
5255 We had hoped to support:
5256 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5257 (except for core file support), but we discovered very late in the release
5258 that it has problems with process groups that render gdb unusable. Sorry
5259 about that. I encourage people to fix it and post the fixes.
5261 * Preliminary ELF and DWARF support
5263 GDB can read ELF object files on System V Release 4, and can handle
5264 debugging records for C, in DWARF format, in ELF files. This support
5265 is preliminary. If you bring up GDB on another SVR4 system, please
5266 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5271 GDB now uses the latest `readline' library. One user-visible change
5272 is that two tabs will list possible command completions, which previously
5273 required typing M-? (meta-question mark, or ESC ?).
5277 The `stepi' bug that many of you noticed has been squashed.
5278 Many bugs in C++ have been handled. Many more remain to be handled.
5279 See the various ChangeLog files (primarily in gdb and bfd) for details.
5281 * State of the MIPS world (in case you wondered):
5283 GDB can understand the symbol tables emitted by the compilers
5284 supplied by most vendors of MIPS-based machines, including DEC. These
5285 symbol tables are in a format that essentially nobody else uses.
5287 Some versions of gcc come with an assembler post-processor called
5288 mips-tfile. This program is required if you want to do source-level
5289 debugging of gcc-compiled programs. I believe FSF does not ship
5290 mips-tfile with gcc version 1, but it will eventually come with gcc
5293 Debugging of g++ output remains a problem. g++ version 1.xx does not
5294 really support it at all. (If you're lucky, you should be able to get
5295 line numbers and stack traces to work, but no parameters or local
5296 variables.) With some work it should be possible to improve the
5299 When gcc version 2 is released, you will have somewhat better luck.
5300 However, even then you will get confusing results for inheritance and
5303 We will eventually provide full debugging of g++ output on
5304 DECstations. This will probably involve some kind of stabs-in-ecoff
5305 encapulation, but the details have not been worked out yet.
5308 *** Changes in GDB-4.2:
5310 * Improved configuration
5312 Only one copy of `configure' exists now, and it is not self-modifying.
5313 Porting BFD is simpler.
5317 The `step' and `next' commands now only stop at the first instruction
5318 of a source line. This prevents the multiple stops that used to occur
5319 in switch statements, for-loops, etc. `Step' continues to stop if a
5320 function that has debugging information is called within the line.
5324 Lots of small bugs fixed. More remain.
5326 * New host supported (not target)
5328 Intel 386 PC clone running Mach i386-none-mach
5331 *** Changes in GDB-4.1:
5333 * Multiple source language support
5335 GDB now has internal scaffolding to handle several source languages.
5336 It determines the type of each source file from its filename extension,
5337 and will switch expression parsing and number formatting to match the
5338 language of the function in the currently selected stack frame.
5339 You can also specifically set the language to be used, with
5340 `set language c' or `set language modula-2'.
5344 GDB now has preliminary support for the GNU Modula-2 compiler,
5345 currently under development at the State University of New York at
5346 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5347 continue through the fall of 1991 and into 1992.
5349 Other Modula-2 compilers are currently not supported, and attempting to
5350 debug programs compiled with them will likely result in an error as the
5351 symbol table is read. Feel free to work on it, though!
5353 There are hooks in GDB for strict type checking and range checking,
5354 in the `Modula-2 philosophy', but they do not currently work.
5358 GDB can now write to executable and core files (e.g. patch
5359 a variable's value). You must turn this switch on, specify
5360 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5361 by assigning a new value to a variable. Modifications take
5364 * Automatic SunOS shared library reading
5366 When you run your program, GDB automatically determines where its
5367 shared libraries (if any) have been loaded, and reads their symbols.
5368 The `share' command is no longer needed. This also works when
5369 examining core files.
5373 You can specify the number of lines that the `list' command shows.
5376 * New machines supported (host and target)
5378 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5379 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5380 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5382 * New hosts supported (not targets)
5384 IBM RT/PC: romp-ibm-aix or rtpc
5386 * New targets supported (not hosts)
5388 AMD 29000 embedded with COFF a29k-none-coff
5389 AMD 29000 embedded with a.out a29k-none-aout
5390 Ultracomputer remote kernel debug a29k-nyu-kern
5392 * New remote interfaces
5398 *** Changes in GDB-4.0:
5402 Wide output is wrapped at good places to make the output more readable.
5404 Gdb now supports cross-debugging from a host machine of one type to a
5405 target machine of another type. Communication with the target system
5406 is over serial lines. The ``target'' command handles connecting to the
5407 remote system; the ``load'' command will download a program into the
5408 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5409 also supports debugging of realtime processes running under VxWorks,
5410 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5411 stub on the target system.
5413 New CPUs supported include the AMD 29000 and Intel 960.
5415 GDB now reads object files and symbol tables via a ``binary file''
5416 library, which allows a single copy of GDB to debug programs of multiple
5417 object file types such as a.out and coff.
5419 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5420 refcard.dvi and refcard.ps are available to format it).
5423 * Control-Variable user interface simplified
5425 All variables that control the operation of the debugger can be set
5426 by the ``set'' command, and displayed by the ``show'' command.
5428 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5429 ``Show prompt'' produces the response:
5430 Gdb's prompt is new-gdb=>.
5432 What follows are the NEW set commands. The command ``help set'' will
5433 print a complete list of old and new set commands. ``help set FOO''
5434 will give a longer description of the variable FOO. ``show'' will show
5435 all of the variable descriptions and their current settings.
5437 confirm on/off: Enables warning questions for operations that are
5438 hard to recover from, e.g. rerunning the program while
5439 it is already running. Default is ON.
5441 editing on/off: Enables EMACS style command line editing
5442 of input. Previous lines can be recalled with
5443 control-P, the current line can be edited with control-B,
5444 you can search for commands with control-R, etc.
5447 history filename NAME: NAME is where the gdb command history
5448 will be stored. The default is .gdb_history,
5449 or the value of the environment variable
5452 history size N: The size, in commands, of the command history. The
5453 default is 256, or the value of the environment variable
5456 history save on/off: If this value is set to ON, the history file will
5457 be saved after exiting gdb. If set to OFF, the
5458 file will not be saved. The default is OFF.
5460 history expansion on/off: If this value is set to ON, then csh-like
5461 history expansion will be performed on
5462 command line input. The default is OFF.
5464 radix N: Sets the default radix for input and output. It can be set
5465 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5466 in the current radix, so "set radix 10" is always a no-op.
5468 height N: This integer value is the number of lines on a page. Default
5469 is 24, the current `stty rows'' setting, or the ``li#''
5470 setting from the termcap entry matching the environment
5473 width N: This integer value is the number of characters on a line.
5474 Default is 80, the current `stty cols'' setting, or the ``co#''
5475 setting from the termcap entry matching the environment
5478 Note: ``set screensize'' is obsolete. Use ``set height'' and
5479 ``set width'' instead.
5481 print address on/off: Print memory addresses in various command displays,
5482 such as stack traces and structure values. Gdb looks
5483 more ``symbolic'' if you turn this off; it looks more
5484 ``machine level'' with it on. Default is ON.
5486 print array on/off: Prettyprint arrays. New convenient format! Default
5489 print demangle on/off: Print C++ symbols in "source" form if on,
5492 print asm-demangle on/off: Same, for assembler level printouts
5495 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5498 * Support for Epoch Environment.
5500 The epoch environment is a version of Emacs v18 with windowing. One
5501 new command, ``inspect'', is identical to ``print'', except that if you
5502 are running in the epoch environment, the value is printed in its own
5506 * Support for Shared Libraries
5508 GDB can now debug programs and core files that use SunOS shared libraries.
5509 Symbols from a shared library cannot be referenced
5510 before the shared library has been linked with the program (this
5511 happens after you type ``run'' and before the function main() is entered).
5512 At any time after this linking (including when examining core files
5513 from dynamically linked programs), gdb reads the symbols from each
5514 shared library when you type the ``sharedlibrary'' command.
5515 It can be abbreviated ``share''.
5517 sharedlibrary REGEXP: Load shared object library symbols for files
5518 matching a unix regular expression. No argument
5519 indicates to load symbols for all shared libraries.
5521 info sharedlibrary: Status of loaded shared libraries.
5526 A watchpoint stops execution of a program whenever the value of an
5527 expression changes. Checking for this slows down execution
5528 tremendously whenever you are in the scope of the expression, but is
5529 quite useful for catching tough ``bit-spreader'' or pointer misuse
5530 problems. Some machines such as the 386 have hardware for doing this
5531 more quickly, and future versions of gdb will use this hardware.
5533 watch EXP: Set a watchpoint (breakpoint) for an expression.
5535 info watchpoints: Information about your watchpoints.
5537 delete N: Deletes watchpoint number N (same as breakpoints).
5538 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5539 enable N: Re-enables watchpoint number N (same as breakpoints).
5542 * C++ multiple inheritance
5544 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5547 * C++ exception handling
5549 Gdb now supports limited C++ exception handling. Besides the existing
5550 ability to breakpoint on an exception handler, gdb can breakpoint on
5551 the raising of an exception (before the stack is peeled back to the
5554 catch FOO: If there is a FOO exception handler in the dynamic scope,
5555 set a breakpoint to catch exceptions which may be raised there.
5556 Multiple exceptions (``catch foo bar baz'') may be caught.
5558 info catch: Lists all exceptions which may be caught in the
5559 current stack frame.
5562 * Minor command changes
5564 The command ``call func (arg, arg, ...)'' now acts like the print
5565 command, except it does not print or save a value if the function's result
5566 is void. This is similar to dbx usage.
5568 The ``up'' and ``down'' commands now always print the frame they end up
5569 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5570 frames without printing.
5572 * New directory command
5574 'dir' now adds directories to the FRONT of the source search path.
5575 The path starts off empty. Source files that contain debug information
5576 about the directory in which they were compiled can be found even
5577 with an empty path; Sun CC and GCC include this information. If GDB can't
5578 find your source file in the current directory, type "dir .".
5580 * Configuring GDB for compilation
5582 For normal use, type ``./configure host''. See README or gdb.texinfo
5585 GDB now handles cross debugging. If you are remotely debugging between
5586 two different machines, type ``./configure host -target=targ''.
5587 Host is the machine where GDB will run; targ is the machine
5588 where the program that you are debugging will run.
5590 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.