1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.7
6 * New command line options
9 This is an alias for the --data-directory option.
11 * GDB supports printing and modifying of variable length automatic arrays
12 as specified in ISO C99.
14 * The ARM simulator now supports instruction level tracing
15 with or without disassembly.
19 GDB now has support for scripting using Guile. Whether this is
20 available is determined at configure time.
21 Guile version 2.0 or greater is required.
22 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
24 * New commands (for set/show, see "New options" below)
28 Invoke CODE by passing it to the Guile interpreter.
32 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
34 info auto-load guile-scripts [regexp]
35 Print the list of automatically loaded Guile scripts.
37 * The source command is now capable of sourcing Guile scripts.
38 This feature is dependent on the debugger being built with Guile support.
42 set print symbol-loading (off|brief|full)
43 show print symbol-loading
44 Control whether to print informational messages when loading symbol
45 information for a file. The default is "full", but when debugging
46 programs with large numbers of shared libraries the amount of output
49 set guile print-stack (none|message|full)
50 show guile print-stack
51 Show a stack trace when an error is encountered in a Guile script.
53 set auto-load guile-scripts (on|off)
54 show auto-load guile-scripts
55 Control auto-loading of Guile script files.
57 maint ada set ignore-descriptive-types (on|off)
58 maint ada show ignore-descriptive-types
59 Control whether the debugger should ignore descriptive types in Ada
60 programs. The default is not to ignore the descriptive types. See
61 the user manual for more details on descriptive types and the intended
64 set auto-connect-native-target
66 Control whether GDB is allowed to automatically connect to the
67 native target for the run, attach, etc. commands when not connected
68 to any target yet. See also "target native" below.
70 set record btrace replay-memory-access (read-only|read-write)
71 show record btrace replay-memory-access
72 Control what memory accesses are allowed during replay.
74 * New features in the GDB remote stub, GDBserver
76 ** New option --debug-format=option1[,option2,...] allows one to add
77 additional text to each output. At present only timestamps
78 are supported: --debug-format=timestamps.
79 Timestamps can also be turned on with the
80 "monitor set debug-format timestamps" command from GDB.
82 * The 'record instruction-history' command now starts counting instructions
83 at one. This also affects the instruction ranges reported by the
84 'record function-call-history' command when given the /i modifier.
86 * The command 'record function-call-history' supports a new modifier '/c' to
87 indent the function names based on their call stack depth.
88 The fields for the '/i' and '/l' modifier have been reordered.
89 The source line range is now prefixed with 'at'.
90 The instruction range is now prefixed with 'inst'.
91 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
92 "record instruction-history" and "list" commands.
94 * The ranges given as arguments to the 'record function-call-history' and
95 'record instruction-history' commands are now inclusive.
97 * The btrace record target now supports the 'record goto' command.
98 For locations inside the execution trace, the back trace is computed
99 based on the information stored in the execution trace.
101 * The btrace record target supports limited reverse execution and replay.
102 The target does not record data and therefore does not allow reading
105 * The "catch syscall" command now works on s390*-linux* targets.
107 * The "compare-sections" command is no longer specific to target
108 remote. It now works with all targets.
110 * All native targets are now consistently called "native".
111 Consequently, the "target child", "target GNU", "target djgpp",
112 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
113 commands have been replaced with "target native". The QNX/NTO port
114 leaves the "procfs" target in place and adds a "native" target for
115 consistency with other ports. The impact on users should be minimal
116 as these commands previously either throwed an error, or were
117 no-ops. The target's name is visible in the output of the following
118 commands: "help target", "info target", "info files", "maint print
121 * The "target native" command now connects to the native target. This
122 can be used to launch native programs even when "set
123 auto-connect-native-target" is set to off.
127 qXfer:btrace:read's annex
128 The qXfer:btrace:read packet supports a new annex 'delta' to read
129 branch trace incrementally.
133 ** Valid Python operations on gdb.Value objects representing
134 structs/classes invoke the corresponding overloaded operators if
138 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
140 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
141 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
142 its alias "share", instead.
144 *** Changes in GDB 7.7
146 * Improved support for process record-replay and reverse debugging on
147 arm*-linux* targets. Support for thumb32 and syscall instruction
148 recording has been added.
150 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
152 * GDB now supports Fission DWP file format version 2.
153 http://gcc.gnu.org/wiki/DebugFission
155 * New convenience function "$_isvoid", to check whether an expression
156 is void. A void expression is an expression where the type of the
157 result is "void". For example, some convenience variables may be
158 "void" when evaluated (e.g., "$_exitcode" before the execution of
159 the program being debugged; or an undefined convenience variable).
160 Another example, when calling a function whose return type is
163 * The "maintenance print objfiles" command now takes an optional regexp.
165 * The "catch syscall" command now works on arm*-linux* targets.
167 * GDB now consistently shows "<not saved>" when printing values of
168 registers the debug info indicates have not been saved in the frame
169 and there's nowhere to retrieve them from
170 (callee-saved/call-clobbered registers):
175 (gdb) info registers rax
178 Before, the former would print "<optimized out>", and the latter
179 "*value not available*".
181 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
186 ** Frame filters and frame decorators have been added.
187 ** Temporary breakpoints are now supported.
188 ** Line tables representation has been added.
189 ** New attribute 'parent_type' for gdb.Field objects.
190 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
191 ** New attribute 'name' for gdb.Type objects.
195 Nios II ELF nios2*-*-elf
196 Nios II GNU/Linux nios2*-*-linux
197 Texas Instruments MSP430 msp430*-*-elf
199 * Removed native configurations
201 Support for these a.out NetBSD and OpenBSD obsolete configurations has
202 been removed. ELF variants of these configurations are kept supported.
204 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
205 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
206 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
207 i[34567]86-*-openbsd3.[0-3]
208 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
209 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
210 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
214 Like "catch throw", but catches a re-thrown exception.
216 Renamed from old "maint check-symtabs".
218 Perform consistency checks on symtabs.
220 Expand symtabs matching an optional regexp.
223 Display the details of GDB configure-time options.
225 maint set|show per-command
226 maint set|show per-command space
227 maint set|show per-command time
228 maint set|show per-command symtab
229 Enable display of per-command gdb resource usage.
231 remove-symbol-file FILENAME
232 remove-symbol-file -a ADDRESS
233 Remove a symbol file added via add-symbol-file. The file to remove
234 can be identified by its filename or by an address that lies within
235 the boundaries of this symbol file in memory.
238 info exceptions REGEXP
239 Display the list of Ada exceptions defined in the program being
240 debugged. If provided, only the exceptions whose names match REGEXP
245 set debug symfile off|on
247 Control display of debugging info regarding reading symbol files and
248 symbol tables within those files
250 set print raw frame-arguments
251 show print raw frame-arguments
252 Set/show whether to print frame arguments in raw mode,
253 disregarding any defined pretty-printers.
255 set remote trace-status-packet
256 show remote trace-status-packet
257 Set/show the use of remote protocol qTStatus packet.
261 Control display of debugging messages related to Nios II targets.
265 Control whether target-assisted range stepping is enabled.
267 set startup-with-shell
268 show startup-with-shell
269 Specifies whether Unix child processes are started via a shell or
274 Use the target memory cache for accesses to the code segment. This
275 improves performance of remote debugging (particularly disassembly).
277 * You can now use a literal value 'unlimited' for options that
278 interpret 0 or -1 as meaning "unlimited". E.g., "set
279 trace-buffer-size unlimited" is now an alias for "set
280 trace-buffer-size -1" and "set height unlimited" is now an alias for
283 * The "set debug symtab-create" debugging option of GDB has been changed to
284 accept a verbosity level. 0 means "off", 1 provides basic debugging
285 output, and values of 2 or greater provides more verbose output.
287 * New command-line options
289 Display the details of GDB configure-time options.
291 * The command 'tsave' can now support new option '-ctf' to save trace
292 buffer in Common Trace Format.
294 * Newly installed $prefix/bin/gcore acts as a shell interface for the
297 * GDB now implements the the C++ 'typeid' operator.
299 * The new convenience variable $_exception holds the exception being
300 thrown or caught at an exception-related catchpoint.
302 * The exception-related catchpoints, like "catch throw", now accept a
303 regular expression which can be used to filter exceptions by type.
305 * The new convenience variable $_exitsignal is automatically set to
306 the terminating signal number when the program being debugged dies
307 due to an uncaught signal.
311 ** All MI commands now accept an optional "--language" option.
312 Support for this feature can be verified by using the "-list-features"
313 command, which should contain "language-option".
315 ** The new command -info-gdb-mi-command allows the user to determine
316 whether a GDB/MI command is supported or not.
318 ** The "^error" result record returned when trying to execute an undefined
319 GDB/MI command now provides a variable named "code" whose content is the
320 "undefined-command" error code. Support for this feature can be verified
321 by using the "-list-features" command, which should contain
322 "undefined-command-error-code".
324 ** The -trace-save MI command can optionally save trace buffer in Common
327 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
329 ** The command -data-list-register-values now accepts an optional
330 "--skip-unavailable" option. When used, only the available registers
333 ** The new command -trace-frame-collected dumps collected variables,
334 computed expressions, tvars, memory and registers in a traceframe.
336 ** The commands -stack-list-locals, -stack-list-arguments and
337 -stack-list-variables now accept an option "--skip-unavailable".
338 When used, only the available locals or arguments are displayed.
340 ** The -exec-run command now accepts an optional "--start" option.
341 When used, the command follows the same semantics as the "start"
342 command, stopping the program's execution at the start of its
343 main subprogram. Support for this feature can be verified using
344 the "-list-features" command, which should contain
345 "exec-run-start-option".
347 ** The new commands -catch-assert and -catch-exceptions insert
348 catchpoints stopping the program when Ada exceptions are raised.
350 ** The new command -info-ada-exceptions provides the equivalent of
351 the new "info exceptions" command.
353 * New system-wide configuration scripts
354 A GDB installation now provides scripts suitable for use as system-wide
355 configuration scripts for the following systems:
359 * GDB now supports target-assigned range stepping with remote targets.
360 This improves the performance of stepping source lines by reducing
361 the number of control packets from/to GDB. See "New remote packets"
364 * GDB now understands the element 'tvar' in the XML traceframe info.
365 It has the id of the collected trace state variables.
367 * On S/390 targets that provide the transactional-execution feature,
368 the program interruption transaction diagnostic block (TDB) is now
369 represented as a number of additional "registers" in GDB.
375 The vCont packet supports a new 'r' action, that tells the remote
376 stub to step through an address range itself, without GDB
377 involvemement at each single-step.
379 qXfer:libraries-svr4:read's annex
380 The previously unused annex of the qXfer:libraries-svr4:read packet
381 is now used to support passing an argument list. The remote stub
382 reports support for this argument list to GDB's qSupported query.
383 The defined arguments are "start" and "prev", used to reduce work
384 necessary for library list updating, resulting in significant
387 * New features in the GDB remote stub, GDBserver
389 ** GDBserver now supports target-assisted range stepping. Currently
390 enabled on x86/x86_64 GNU/Linux targets.
392 ** GDBserver now adds element 'tvar' in the XML in the reply to
393 'qXfer:traceframe-info:read'. It has the id of the collected
394 trace state variables.
396 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
399 * New 'z' formatter for printing and examining memory, this displays the
400 value as hexadecimal zero padded on the left to the size of the type.
402 * GDB can now use Windows x64 unwinding data.
404 * The "set remotebaud" command has been replaced by "set serial baud".
405 Similarly, "show remotebaud" has been replaced by "show serial baud".
406 The "set remotebaud" and "show remotebaud" commands are still available
407 to provide backward compatibility with older versions of GDB.
409 *** Changes in GDB 7.6
411 * Target record has been renamed to record-full.
412 Record/replay is now enabled with the "record full" command.
413 This also affects settings that are associated with full record/replay
414 that have been moved from "set/show record" to "set/show record full":
416 set|show record full insn-number-max
417 set|show record full stop-at-limit
418 set|show record full memory-query
420 * A new record target "record-btrace" has been added. The new target
421 uses hardware support to record the control-flow of a process. It
422 does not support replaying the execution, but it implements the
423 below new commands for investigating the recorded execution log.
424 This new recording method can be enabled using:
428 The "record-btrace" target is only available on Intel Atom processors
429 and requires a Linux kernel 2.6.32 or later.
431 * Two new commands have been added for record/replay to give information
432 about the recorded execution without having to replay the execution.
433 The commands are only supported by "record btrace".
435 record instruction-history prints the execution history at
436 instruction granularity
438 record function-call-history prints the execution history at
441 * New native configurations
443 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
444 FreeBSD/powerpc powerpc*-*-freebsd
445 x86_64/Cygwin x86_64-*-cygwin*
446 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
450 ARM AArch64 aarch64*-*-elf
451 ARM AArch64 GNU/Linux aarch64*-*-linux
452 Lynx 178 PowerPC powerpc-*-lynx*178
453 x86_64/Cygwin x86_64-*-cygwin*
454 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
456 * If the configured location of system.gdbinit file (as given by the
457 --with-system-gdbinit option at configure time) is in the
458 data-directory (as specified by --with-gdb-datadir at configure
459 time) or in one of its subdirectories, then GDB will look for the
460 system-wide init file in the directory specified by the
461 --data-directory command-line option.
463 * New command line options:
465 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
466 other initialization files, unlike -nx which disables all of them.
468 * Removed command line options
470 -epoch This was used by the gdb mode in Epoch, an ancient fork of
473 * The 'ptype' and 'whatis' commands now accept an argument to control
476 * 'info proc' now works on some core files.
480 ** Vectors can be created with gdb.Type.vector.
482 ** Python's atexit.register now works in GDB.
484 ** Types can be pretty-printed via a Python API.
486 ** Python 3 is now supported (in addition to Python 2.4 or later)
488 ** New class gdb.Architecture exposes GDB's internal representation
489 of architecture in the Python API.
491 ** New method Frame.architecture returns the gdb.Architecture object
492 corresponding to the frame's architecture.
494 * New Python-based convenience functions:
496 ** $_memeq(buf1, buf2, length)
497 ** $_streq(str1, str2)
499 ** $_regex(str, regex)
501 * The 'cd' command now defaults to using '~' (the home directory) if not
504 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
505 default for GCC since November 2000.
507 * The command 'forward-search' can now be abbreviated as 'fo'.
509 * The command 'info tracepoints' can now display 'installed on target'
510 or 'not installed on target' for each non-pending location of tracepoint.
512 * New configure options
514 --enable-libmcheck/--disable-libmcheck
515 By default, development versions are built with -lmcheck on hosts
516 that support it, in order to help track memory corruption issues.
517 Release versions, on the other hand, are built without -lmcheck
518 by default. The --enable-libmcheck/--disable-libmcheck configure
519 options allow the user to override that default.
520 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
521 This configure option allows the user to build GDB with
522 libbabeltrace using which GDB can read Common Trace Format data.
524 * New commands (for set/show, see "New options" below)
527 Catch signals. This is similar to "handle", but allows commands and
528 conditions to be attached.
531 List the BFDs known to GDB.
533 python-interactive [command]
535 Start a Python interactive prompt, or evaluate the optional command
536 and print the result of expressions.
539 "py" is a new alias for "python".
541 enable type-printer [name]...
542 disable type-printer [name]...
543 Enable or disable type printers.
547 ** For the Renesas Super-H architecture, the "regs" command has been removed
548 (has been deprecated in GDB 7.5), and "info all-registers" should be used
553 set print type methods (on|off)
554 show print type methods
555 Control whether method declarations are displayed by "ptype".
556 The default is to show them.
558 set print type typedefs (on|off)
559 show print type typedefs
560 Control whether typedef definitions are displayed by "ptype".
561 The default is to show them.
563 set filename-display basename|relative|absolute
564 show filename-display
565 Control the way in which filenames is displayed.
566 The default is "relative", which preserves previous behavior.
568 set trace-buffer-size
569 show trace-buffer-size
570 Request target to change the size of trace buffer.
572 set remote trace-buffer-size-packet auto|on|off
573 show remote trace-buffer-size-packet
574 Control the use of the remote protocol `QTBuffer:size' packet.
578 Control display of debugging messages related to ARM AArch64.
581 set debug coff-pe-read
582 show debug coff-pe-read
583 Control display of debugging messages related to reading of COFF/PE
588 Control display of debugging messages related to Mach-O symbols
591 set debug notification
592 show debug notification
593 Control display of debugging info for async remote notification.
597 ** Command parameter changes are now notified using new async record
598 "=cmd-param-changed".
599 ** Trace frame changes caused by command "tfind" are now notified using
600 new async record "=traceframe-changed".
601 ** The creation, deletion and modification of trace state variables
602 are now notified using new async records "=tsv-created",
603 "=tsv-deleted" and "=tsv-modified".
604 ** The start and stop of process record are now notified using new
605 async record "=record-started" and "=record-stopped".
606 ** Memory changes are now notified using new async record
608 ** The data-disassemble command response will include a "fullname" field
609 containing the absolute file name when source has been requested.
610 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
611 command, to allow pattern filling of memory areas.
612 ** New commands "-catch-load"/"-catch-unload" added for intercepting
613 library load/unload events.
614 ** The response to breakpoint commands and breakpoint async records
615 includes an "installed" field containing a boolean state about each
616 non-pending tracepoint location is whether installed on target or not.
617 ** Output of the "-trace-status" command includes a "trace-file" field
618 containing the name of the trace file being examined. This field is
619 optional, and only present when examining a trace file.
620 ** The "fullname" field is now always present along with the "file" field,
621 even if the file cannot be found by GDB.
623 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
624 You must have the LZMA library available when configuring GDB for this
625 feature to be enabled. For more information, see:
626 http://fedoraproject.org/wiki/Features/MiniDebugInfo
631 Set the size of trace buffer. The remote stub reports support for this
632 packet to gdb's qSupported query.
635 Enable Branch Trace Store (BTS)-based branch tracing for the current
636 thread. The remote stub reports support for this packet to gdb's
640 Disable branch tracing for the current thread. The remote stub reports
641 support for this packet to gdb's qSupported query.
644 Read the traced branches for the current thread. The remote stub
645 reports support for this packet to gdb's qSupported query.
647 *** Changes in GDB 7.5
649 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
650 for more x32 ABI info.
652 * GDB now supports access to MIPS DSP registers on Linux targets.
654 * GDB now supports debugging microMIPS binaries.
656 * The "info os" command on GNU/Linux can now display information on
657 several new classes of objects managed by the operating system:
658 "info os procgroups" lists process groups
659 "info os files" lists file descriptors
660 "info os sockets" lists internet-domain sockets
661 "info os shm" lists shared-memory regions
662 "info os semaphores" lists semaphores
663 "info os msg" lists message queues
664 "info os modules" lists loaded kernel modules
666 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
667 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
668 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
669 options and inspect the probe arguments using the new $_probe_arg family
670 of convenience variables. You can obtain more information about SystemTap
671 in <http://sourceware.org/systemtap/>.
673 * GDB now supports reversible debugging on ARM, it allows you to
674 debug basic ARM and THUMB instructions, and provides
675 record/replay support.
677 * The option "symbol-reloading" has been deleted as it is no longer used.
681 ** GDB commands implemented in Python can now be put in command class
684 ** The "maint set python print-stack on|off" is now deleted.
686 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
687 apply "flag enum"-style pretty-printing to any enum.
689 ** gdb.lookup_symbol can now work when there is no current frame.
691 ** gdb.Symbol now has a 'line' attribute, holding the line number in
692 the source at which the symbol was defined.
694 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
695 method 'value'. The former indicates whether the symbol needs a
696 frame in order to compute its value, and the latter computes the
699 ** A new method 'referenced_value' on gdb.Value objects which can
700 dereference pointer as well as C++ reference values.
702 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
703 which return the global and static blocks (as gdb.Block objects),
704 of the underlying symbol table, respectively.
706 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
707 object associated with a PC value.
709 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
710 of the address range occupied by code for the current source line.
712 * Go language support.
713 GDB now supports debugging programs written in the Go programming
716 * GDBserver now supports stdio connections.
717 E.g. (gdb) target remote | ssh myhost gdbserver - hello
719 * The binary "gdbtui" can no longer be built or installed.
720 Use "gdb -tui" instead.
722 * GDB will now print "flag" enums specially. A flag enum is one where
723 all the enumerator values have no bits in common when pairwise
724 "and"ed. When printing a value whose type is a flag enum, GDB will
725 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
726 (gdb) print (enum E) 3
729 * The filename part of a linespec will now match trailing components
730 of a source file name. For example, "break gcc/expr.c:1000" will
731 now set a breakpoint in build/gcc/expr.c, but not
734 * The "info proc" and "generate-core-file" commands will now also
735 work on remote targets connected to GDBserver on Linux.
737 * The command "info catch" has been removed. It has been disabled
740 * The "catch exception" and "catch assert" commands now accept
741 a condition at the end of the command, much like the "break"
742 command does. For instance:
744 (gdb) catch exception Constraint_Error if Barrier = True
746 Previously, it was possible to add a condition to such catchpoints,
747 but it had to be done as a second step, after the catchpoint had been
748 created, using the "condition" command.
750 * The "info static-tracepoint-marker" command will now also work on
751 native Linux targets with in-process agent.
753 * GDB can now set breakpoints on inlined functions.
755 * The .gdb_index section has been updated to include symbols for
756 inlined functions. GDB will ignore older .gdb_index sections by
757 default, which could cause symbol files to be loaded more slowly
758 until their .gdb_index sections can be recreated. The new command
759 "set use-deprecated-index-sections on" will cause GDB to use any older
760 .gdb_index sections it finds. This will restore performance, but the
761 ability to set breakpoints on inlined functions will be lost in symbol
762 files with older .gdb_index sections.
764 The .gdb_index section has also been updated to record more information
765 about each symbol. This speeds up the "info variables", "info functions"
766 and "info types" commands when used with programs having the .gdb_index
767 section, as well as speeding up debugging with shared libraries using
768 the .gdb_index section.
770 * Ada support for GDB/MI Variable Objects has been added.
772 * GDB can now support 'breakpoint always-inserted mode' in 'record'
777 ** New command -info-os is the MI equivalent of "info os".
779 ** Output logs ("set logging" and related) now include MI output.
783 ** "set use-deprecated-index-sections on|off"
784 "show use-deprecated-index-sections on|off"
785 Controls the use of deprecated .gdb_index sections.
787 ** "catch load" and "catch unload" can be used to stop when a shared
788 library is loaded or unloaded, respectively.
790 ** "enable count" can be used to auto-disable a breakpoint after
793 ** "info vtbl" can be used to show the virtual method tables for
794 C++ and Java objects.
796 ** "explore" and its sub commands "explore value" and "explore type"
797 can be used to recursively explore values and types of
798 expressions. These commands are available only if GDB is
799 configured with '--with-python'.
801 ** "info auto-load" shows status of all kinds of auto-loaded files,
802 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
803 sequences of commands files, "info auto-load python-scripts"
804 shows status of auto-loading Python script files,
805 "info auto-load local-gdbinit" shows status of loading init file
806 (.gdbinit) from current directory and "info auto-load libthread-db" shows
807 status of inferior specific thread debugging shared library loading.
809 ** "info auto-load-scripts", "set auto-load-scripts on|off"
810 and "show auto-load-scripts" commands have been deprecated, use their
811 "info auto-load python-scripts", "set auto-load python-scripts on|off"
812 and "show auto-load python-scripts" counterparts instead.
814 ** "dprintf location,format,args..." creates a dynamic printf, which
815 is basically a breakpoint that does a printf and immediately
816 resumes your program's execution, so it is like a printf that you
817 can insert dynamically at runtime instead of at compiletime.
819 ** "set print symbol"
821 Controls whether GDB attempts to display the symbol, if any,
822 corresponding to addresses it prints. This defaults to "on", but
823 you can set it to "off" to restore GDB's previous behavior.
825 * Deprecated commands
827 ** For the Renesas Super-H architecture, the "regs" command has been
828 deprecated, and "info all-registers" should be used instead.
832 Renesas RL78 rl78-*-elf
833 HP OpenVMS ia64 ia64-hp-openvms*
835 * GDBserver supports evaluation of breakpoint conditions. When
836 support is advertised by GDBserver, GDB may be told to send the
837 breakpoint conditions in bytecode form to GDBserver. GDBserver
838 will only report the breakpoint trigger to GDB when its condition
844 show mips compression
845 Select the compressed ISA encoding used in functions that have no symbol
846 information available. The encoding can be set to either of:
849 and is updated automatically from ELF file flags if available.
851 set breakpoint condition-evaluation
852 show breakpoint condition-evaluation
853 Control whether breakpoint conditions are evaluated by GDB ("host") or by
854 GDBserver ("target"). Default option "auto" chooses the most efficient
856 This option can improve debugger efficiency depending on the speed of the
860 Disable auto-loading globally.
863 Show auto-loading setting of all kinds of auto-loaded files.
865 set auto-load gdb-scripts on|off
866 show auto-load gdb-scripts
867 Control auto-loading of GDB canned sequences of commands files.
869 set auto-load python-scripts on|off
870 show auto-load python-scripts
871 Control auto-loading of Python script files.
873 set auto-load local-gdbinit on|off
874 show auto-load local-gdbinit
875 Control loading of init file (.gdbinit) from current directory.
877 set auto-load libthread-db on|off
878 show auto-load libthread-db
879 Control auto-loading of inferior specific thread debugging shared library.
881 set auto-load scripts-directory <dir1>[:<dir2>...]
882 show auto-load scripts-directory
883 Set a list of directories from which to load auto-loaded scripts.
884 Automatically loaded Python scripts and GDB scripts are located in one
885 of the directories listed by this option.
886 The delimiter (':' above) may differ according to the host platform.
888 set auto-load safe-path <dir1>[:<dir2>...]
889 show auto-load safe-path
890 Set a list of directories from which it is safe to auto-load files.
891 The delimiter (':' above) may differ according to the host platform.
893 set debug auto-load on|off
895 Control display of debugging info for auto-loading the files above.
897 set dprintf-style gdb|call|agent
899 Control the way in which a dynamic printf is performed; "gdb"
900 requests a GDB printf command, while "call" causes dprintf to call a
901 function in the inferior. "agent" requests that the target agent
902 (such as GDBserver) do the printing.
904 set dprintf-function <expr>
905 show dprintf-function
906 set dprintf-channel <expr>
908 Set the function and optional first argument to the call when using
909 the "call" style of dynamic printf.
911 set disconnected-dprintf on|off
912 show disconnected-dprintf
913 Control whether agent-style dynamic printfs continue to be in effect
914 after GDB disconnects.
916 * New configure options
919 Configure default value for the 'set auto-load scripts-directory'
920 setting above. It defaults to '$debugdir:$datadir/auto-load',
921 $debugdir representing global debugging info directories (available
922 via 'show debug-file-directory') and $datadir representing GDB's data
923 directory (available via 'show data-directory').
925 --with-auto-load-safe-path
926 Configure default value for the 'set auto-load safe-path' setting
927 above. It defaults to the --with-auto-load-dir setting.
929 --without-auto-load-safe-path
930 Set 'set auto-load safe-path' to '/', effectively disabling this
935 z0/z1 conditional breakpoints extension
937 The z0/z1 breakpoint insertion packets have been extended to carry
938 a list of conditional expressions over to the remote stub depending on the
939 condition evaluation mode. The use of this extension can be controlled
940 via the "set remote conditional-breakpoints-packet" command.
944 Specify the signals which the remote stub may pass to the debugged
945 program without GDB involvement.
947 * New command line options
949 --init-command=FILE, -ix Like --command, -x but execute it
950 before loading inferior.
951 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
952 execute it before loading inferior.
954 *** Changes in GDB 7.4
956 * GDB now handles ambiguous linespecs more consistently; the existing
957 FILE:LINE support has been expanded to other types of linespecs. A
958 breakpoint will now be set on all matching locations in all
959 inferiors, and locations will be added or removed according to
962 * GDB now allows you to skip uninteresting functions and files when
963 stepping with the "skip function" and "skip file" commands.
965 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
966 and "show remote hardware-watchpoint-length-limit". These allows to
967 set or show the maximum length limit (in bytes) of a remote
968 target hardware watchpoint.
970 This allows e.g. to use "unlimited" hardware watchpoints with the
971 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
972 watchpoints are slower than real hardware watchpoints but are
973 significantly faster than gdb software watchpoints.
977 ** The register_pretty_printer function in module gdb.printing now takes
978 an optional `replace' argument. If True, the new printer replaces any
981 ** The "maint set python print-stack on|off" command has been
982 deprecated and will be deleted in GDB 7.5.
983 A new command: "set python print-stack none|full|message" has
984 replaced it. Additionally, the default for "print-stack" is
985 now "message", which just prints the error message without
988 ** A prompt substitution hook (prompt_hook) is now available to the
991 ** A new Python module, gdb.prompt has been added to the GDB Python
992 modules library. This module provides functionality for
993 escape sequences in prompts (used by set/show
994 extended-prompt). These escape sequences are replaced by their
997 ** Python commands and convenience-functions located in
998 'data-directory'/python/gdb/command and
999 'data-directory'/python/gdb/function are now automatically loaded
1002 ** Blocks now provide four new attributes. global_block and
1003 static_block will return the global and static blocks
1004 respectively. is_static and is_global are boolean attributes
1005 that indicate if the block is one of those two types.
1007 ** Symbols now provide the "type" attribute, the type of the symbol.
1009 ** The "gdb.breakpoint" function has been deprecated in favor of
1012 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1013 of a function. This class is based on the "finish" command
1014 available in the CLI.
1016 ** Type objects for struct and union types now allow access to
1017 the fields using standard Python dictionary (mapping) methods.
1018 For example, "some_type['myfield']" now works, as does
1019 "some_type.items()".
1021 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1024 ** A new function, "deep_items" has been added to the gdb.types
1025 module in the GDB Python modules library. This function returns
1026 an iterator over the fields of a struct or union type. Unlike
1027 the standard Python "iteritems" method, it will recursively traverse
1028 any anonymous fields.
1032 ** "*stopped" events can report several new "reason"s, such as
1035 ** Breakpoint changes are now notified using new async records, like
1036 "=breakpoint-modified".
1038 ** New command -ada-task-info.
1040 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1041 $sdir specifies the default system locations of shared libraries.
1042 $pdir specifies the directory where the libpthread used by the application
1045 GDB no longer looks in $sdir and $pdir after it has searched the directories
1046 mentioned in libthread-db-search-path. If you want to search those
1047 directories, they must be specified in libthread-db-search-path.
1048 The default value of libthread-db-search-path on GNU/Linux and Solaris
1049 systems is now "$sdir:$pdir".
1051 $pdir is not supported by gdbserver, it is currently ignored.
1052 $sdir is supported by gdbserver.
1054 * New configure option --with-iconv-bin.
1055 When using the internationalization support like the one in the GNU C
1056 library, GDB will invoke the "iconv" program to get a list of supported
1057 character sets. If this program lives in a non-standard location, one can
1058 use this option to specify where to find it.
1060 * When natively debugging programs on PowerPC BookE processors running
1061 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1062 watchpoints, which specify a mask in addition to an address to watch.
1063 The mask specifies that some bits of an address (the bits which are
1064 reset in the mask) should be ignored when matching the address accessed
1065 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1066 section in the user manual for more details.
1068 * The new option --once causes GDBserver to stop listening for connections once
1069 the first connection is made. The listening port used by GDBserver will
1070 become available after that.
1072 * New commands "info macros" and "alias" have been added.
1074 * New function parameters suffix @entry specifies value of function parameter
1075 at the time the function got called. Entry values are available only since
1081 "!" is now an alias of the "shell" command.
1082 Note that no space is needed between "!" and SHELL COMMAND.
1086 watch EXPRESSION mask MASK_VALUE
1087 The watch command now supports the mask argument which allows creation
1088 of masked watchpoints, if the current architecture supports this feature.
1090 info auto-load-scripts [REGEXP]
1091 This command was formerly named "maintenance print section-scripts".
1092 It is now generally useful and is no longer a maintenance-only command.
1094 info macro [-all] [--] MACRO
1095 The info macro command has new options `-all' and `--'. The first for
1096 printing all definitions of a macro. The second for explicitly specifying
1097 the end of arguments and the beginning of the macro name in case the macro
1098 name starts with a hyphen.
1100 collect[/s] EXPRESSIONS
1101 The tracepoint collect command now takes an optional modifier "/s"
1102 that directs it to dereference pointer-to-character types and
1103 collect the bytes of memory up to a zero byte. The behavior is
1104 similar to what you see when you use the regular print command on a
1105 string. An optional integer following the "/s" sets a bound on the
1106 number of bytes that will be collected.
1109 The trace start command now interprets any supplied arguments as a
1110 note to be recorded with the trace run, with an effect similar to
1111 setting the variable trace-notes.
1114 The trace stop command now interprets any arguments as a note to be
1115 mentioned along with the tstatus report that the trace was stopped
1116 with a command. The effect is similar to setting the variable
1119 * Tracepoints can now be enabled and disabled at any time after a trace
1120 experiment has been started using the standard "enable" and "disable"
1121 commands. It is now possible to start a trace experiment with no enabled
1122 tracepoints; GDB will display a warning, but will allow the experiment to
1123 begin, assuming that tracepoints will be enabled as needed while the trace
1126 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1127 locations with 4-byte instructions, when they were previously
1128 limited to locations with instructions of 5 bytes or longer.
1132 set debug dwarf2-read
1133 show debug dwarf2-read
1134 Turns on or off display of debugging messages related to reading
1135 DWARF debug info. The default is off.
1137 set debug symtab-create
1138 show debug symtab-create
1139 Turns on or off display of debugging messages related to symbol table
1140 creation. The default is off.
1143 show extended-prompt
1144 Set the GDB prompt, and allow escape sequences to be inserted to
1145 display miscellaneous information (see 'help set extended-prompt'
1146 for the list of sequences). This prompt (and any information
1147 accessed through the escape sequences) is updated every time the
1148 prompt is displayed.
1150 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1151 show print entry-values
1152 Set printing of frame argument values at function entry. In some cases
1153 GDB can determine the value of function argument which was passed by the
1154 function caller, even if the value was modified inside the called function.
1156 set debug entry-values
1157 show debug entry-values
1158 Control display of debugging info for determining frame argument values at
1159 function entry and virtual tail call frames.
1161 set basenames-may-differ
1162 show basenames-may-differ
1163 Set whether a source file may have multiple base names.
1164 (A "base name" is the name of a file with the directory part removed.
1165 Example: The base name of "/home/user/hello.c" is "hello.c".)
1166 If set, GDB will canonicalize file names (e.g., expand symlinks)
1167 before comparing them. Canonicalization is an expensive operation,
1168 but it allows the same file be known by more than one base name.
1169 If not set (the default), all source files are assumed to have just
1170 one base name, and gdb will do file name comparisons more efficiently.
1176 Set a user name and notes for the current and any future trace runs.
1177 This is useful for long-running and/or disconnected traces, to
1178 inform others (or yourself) as to who is running the trace, supply
1179 contact information, or otherwise explain what is going on.
1181 set trace-stop-notes
1182 show trace-stop-notes
1183 Set a note attached to the trace run, that is displayed when the
1184 trace has been stopped by a tstop command. This is useful for
1185 instance as an explanation, if you are stopping a trace run that was
1186 started by someone else.
1188 * New remote packets
1192 Dynamically enable a tracepoint in a started trace experiment.
1196 Dynamically disable a tracepoint in a started trace experiment.
1200 Set the user and notes of the trace run.
1204 Query the current status of a tracepoint.
1208 Query the minimum length of instruction at which a fast tracepoint may
1211 * Dcache size (number of lines) and line-size are now runtime-configurable
1212 via "set dcache line" and "set dcache line-size" commands.
1216 Texas Instruments TMS320C6x tic6x-*-*
1220 Renesas RL78 rl78-*-elf
1222 *** Changes in GDB 7.3.1
1224 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1226 *** Changes in GDB 7.3
1228 * GDB has a new command: "thread find [REGEXP]".
1229 It finds the thread id whose name, target id, or thread extra info
1230 matches the given regular expression.
1232 * The "catch syscall" command now works on mips*-linux* targets.
1234 * The -data-disassemble MI command now supports modes 2 and 3 for
1235 dumping the instruction opcodes.
1237 * New command line options
1239 -data-directory DIR Specify DIR as the "data-directory".
1240 This is mostly for testing purposes.
1242 * The "maint set python auto-load on|off" command has been renamed to
1243 "set auto-load-scripts on|off".
1245 * GDB has a new command: "set directories".
1246 It is like the "dir" command except that it replaces the
1247 source path list instead of augmenting it.
1249 * GDB now understands thread names.
1251 On GNU/Linux, "info threads" will display the thread name as set by
1252 prctl or pthread_setname_np.
1254 There is also a new command, "thread name", which can be used to
1255 assign a name internally for GDB to display.
1258 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1259 has been integrated into GDB.
1263 ** The function gdb.Write now accepts an optional keyword 'stream'.
1264 This keyword, when provided, will direct the output to either
1265 stdout, stderr, or GDB's logging output.
1267 ** Parameters can now be be sub-classed in Python, and in particular
1268 you may implement the get_set_doc and get_show_doc functions.
1269 This improves how Parameter set/show documentation is processed
1270 and allows for more dynamic content.
1272 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1273 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1274 have an is_valid method.
1276 ** Breakpoints can now be sub-classed in Python, and in particular
1277 you may implement a 'stop' function that is executed each time
1278 the inferior reaches that breakpoint.
1280 ** New function gdb.lookup_global_symbol looks up a global symbol.
1282 ** GDB values in Python are now callable if the value represents a
1283 function. For example, if 'some_value' represents a function that
1284 takes two integer parameters and returns a value, you can call
1285 that function like so:
1287 result = some_value (10,20)
1289 ** Module gdb.types has been added.
1290 It contains a collection of utilities for working with gdb.Types objects:
1291 get_basic_type, has_field, make_enum_dict.
1293 ** Module gdb.printing has been added.
1294 It contains utilities for writing and registering pretty-printers.
1295 New classes: PrettyPrinter, SubPrettyPrinter,
1296 RegexpCollectionPrettyPrinter.
1297 New function: register_pretty_printer.
1299 ** New commands "info pretty-printers", "enable pretty-printer" and
1300 "disable pretty-printer" have been added.
1302 ** gdb.parameter("directories") is now available.
1304 ** New function gdb.newest_frame returns the newest frame in the
1307 ** The gdb.InferiorThread class has a new "name" attribute. This
1308 holds the thread's name.
1310 ** Python Support for Inferior events.
1311 Python scripts can add observers to be notified of events
1312 occurring in the process being debugged.
1313 The following events are currently supported:
1314 - gdb.events.cont Continue event.
1315 - gdb.events.exited Inferior exited event.
1316 - gdb.events.stop Signal received, and Breakpoint hit events.
1320 ** GDB now puts template parameters in scope when debugging in an
1321 instantiation. For example, if you have:
1323 template<int X> int func (void) { return X; }
1325 then if you step into func<5>, "print X" will show "5". This
1326 feature requires proper debuginfo support from the compiler; it
1327 was added to GCC 4.5.
1329 ** The motion commands "next", "finish", "until", and "advance" now
1330 work better when exceptions are thrown. In particular, GDB will
1331 no longer lose control of the inferior; instead, the GDB will
1332 stop the inferior at the point at which the exception is caught.
1333 This functionality requires a change in the exception handling
1334 code that was introduced in GCC 4.5.
1336 * GDB now follows GCC's rules on accessing volatile objects when
1337 reading or writing target state during expression evaluation.
1338 One notable difference to prior behavior is that "print x = 0"
1339 no longer generates a read of x; the value of the assignment is
1340 now always taken directly from the value being assigned.
1342 * GDB now has some support for using labels in the program's source in
1343 linespecs. For instance, you can use "advance label" to continue
1344 execution to a label.
1346 * GDB now has support for reading and writing a new .gdb_index
1347 section. This section holds a fast index of DWARF debugging
1348 information and can be used to greatly speed up GDB startup and
1349 operation. See the documentation for `save gdb-index' for details.
1351 * The "watch" command now accepts an optional "-location" argument.
1352 When used, this causes GDB to watch the memory referred to by the
1353 expression. Such a watchpoint is never deleted due to it going out
1356 * GDB now supports thread debugging of core dumps on GNU/Linux.
1358 GDB now activates thread debugging using the libthread_db library
1359 when debugging GNU/Linux core dumps, similarly to when debugging
1360 live processes. As a result, when debugging a core dump file, GDB
1361 is now able to display pthread_t ids of threads. For example, "info
1362 threads" shows the same output as when debugging the process when it
1363 was live. In earlier releases, you'd see something like this:
1366 * 1 LWP 6780 main () at main.c:10
1368 While now you see this:
1371 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1373 It is also now possible to inspect TLS variables when debugging core
1376 When debugging a core dump generated on a machine other than the one
1377 used to run GDB, you may need to point GDB at the correct
1378 libthread_db library with the "set libthread-db-search-path"
1379 command. See the user manual for more details on this command.
1381 * When natively debugging programs on PowerPC BookE processors running
1382 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1383 which stop execution of the inferior whenever it executes an instruction
1384 at any address within the specified range. See the "PowerPC Embedded"
1385 section in the user manual for more details.
1387 * New features in the GDB remote stub, GDBserver
1389 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1390 and i686 LynxOS (version 5.x).
1392 ** GDBserver is now supported on Blackfin Linux.
1394 * New native configurations
1396 ia64 HP-UX ia64-*-hpux*
1400 Analog Devices, Inc. Blackfin Processor bfin-*
1402 * Ada task switching is now supported on sparc-elf targets when
1403 debugging a program using the Ravenscar Profile. For more information,
1404 see the "Tasking Support when using the Ravenscar Profile" section
1405 in the GDB user manual.
1407 * Guile support was removed.
1409 * New features in the GNU simulator
1411 ** The --map-info flag lists all known core mappings.
1413 ** CFI flashes may be simulated via the "cfi" device.
1415 *** Changes in GDB 7.2
1417 * Shared library support for remote targets by default
1419 When GDB is configured for a generic, non-OS specific target, like
1420 for example, --target=arm-eabi or one of the many *-*-elf targets,
1421 GDB now queries remote stubs for loaded shared libraries using the
1422 `qXfer:libraries:read' packet. Previously, shared library support
1423 was always disabled for such configurations.
1427 ** Argument Dependent Lookup (ADL)
1429 In C++ ADL lookup directs function search to the namespaces of its
1430 arguments even if the namespace has not been imported.
1440 Here the compiler will search for `foo' in the namespace of 'b'
1441 and find A::foo. GDB now supports this. This construct is commonly
1442 used in the Standard Template Library for operators.
1444 ** Improved User Defined Operator Support
1446 In addition to member operators, GDB now supports lookup of operators
1447 defined in a namespace and imported with a `using' directive, operators
1448 defined in the global scope, operators imported implicitly from an
1449 anonymous namespace, and the ADL operators mentioned in the previous
1451 GDB now also supports proper overload resolution for all the previously
1452 mentioned flavors of operators.
1454 ** static const class members
1456 Printing of static const class members that are initialized in the
1457 class definition has been fixed.
1459 * Windows Thread Information Block access.
1461 On Windows targets, GDB now supports displaying the Windows Thread
1462 Information Block (TIB) structure. This structure is visible either
1463 by using the new command `info w32 thread-information-block' or, by
1464 dereferencing the new convenience variable named `$_tlb', a
1465 thread-specific pointer to the TIB. This feature is also supported
1466 when remote debugging using GDBserver.
1468 * Static tracepoints
1470 Static tracepoints are calls in the user program into a tracing
1471 library. One such library is a port of the LTTng kernel tracer to
1472 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1473 When debugging with GDBserver, GDB now supports combining the GDB
1474 tracepoint machinery with such libraries. For example: the user can
1475 use GDB to probe a static tracepoint marker (a call from the user
1476 program into the tracing library) with the new "strace" command (see
1477 "New commands" below). This creates a "static tracepoint" in the
1478 breakpoint list, that can be manipulated with the same feature set
1479 as fast and regular tracepoints. E.g., collect registers, local and
1480 global variables, collect trace state variables, and define
1481 tracepoint conditions. In addition, the user can collect extra
1482 static tracepoint marker specific data, by collecting the new
1483 $_sdata internal variable. When analyzing the trace buffer, you can
1484 inspect $_sdata like any other variable available to GDB. For more
1485 information, see the "Tracepoints" chapter in GDB user manual. New
1486 remote packets have been defined to support static tracepoints, see
1487 the "New remote packets" section below.
1489 * Better reconstruction of tracepoints after disconnected tracing
1491 GDB will attempt to download the original source form of tracepoint
1492 definitions when starting a trace run, and then will upload these
1493 upon reconnection to the target, resulting in a more accurate
1494 reconstruction of the tracepoints that are in use on the target.
1498 You can now exercise direct control over the ways that GDB can
1499 affect your program. For instance, you can disallow the setting of
1500 breakpoints, so that the program can run continuously (assuming
1501 non-stop mode). In addition, the "observer" variable is available
1502 to switch all of the different controls; in observer mode, GDB
1503 cannot affect the target's behavior at all, which is useful for
1504 tasks like diagnosing live systems in the field.
1506 * The new convenience variable $_thread holds the number of the
1509 * New remote packets
1513 Return the address of the Windows Thread Information Block of a given thread.
1517 In response to several of the tracepoint packets, the target may now
1518 also respond with a number of intermediate `qRelocInsn' request
1519 packets before the final result packet, to have GDB handle
1520 relocating an instruction to execute at a different address. This
1521 is particularly useful for stubs that support fast tracepoints. GDB
1522 reports support for this feature in the qSupported packet.
1526 List static tracepoint markers in the target program.
1530 List static tracepoint markers at a given address in the target
1533 qXfer:statictrace:read
1535 Read the static trace data collected (by a `collect $_sdata'
1536 tracepoint action). The remote stub reports support for this packet
1537 to gdb's qSupported query.
1541 Send the current settings of GDB's permission flags.
1545 Send part of the source (textual) form of a tracepoint definition,
1546 which includes location, conditional, and action list.
1548 * The source command now accepts a -s option to force searching for the
1549 script in the source search path even if the script name specifies
1552 * New features in the GDB remote stub, GDBserver
1554 - GDBserver now support tracepoints (including fast tracepoints, and
1555 static tracepoints). The feature is currently supported by the
1556 i386-linux and amd64-linux builds. See the "Tracepoints support
1557 in gdbserver" section in the manual for more information.
1559 GDBserver JIT compiles the tracepoint's conditional agent
1560 expression bytecode into native code whenever possible for low
1561 overhead dynamic tracepoints conditionals. For such tracepoints,
1562 an expression that examines program state is evaluated when the
1563 tracepoint is reached, in order to determine whether to capture
1564 trace data. If the condition is simple and false, processing the
1565 tracepoint finishes very quickly and no data is gathered.
1567 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1568 for static tracepoints support.
1570 - GDBserver now supports x86_64 Windows 64-bit debugging.
1572 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1573 it understands register description.
1575 * The --batch flag now disables pagination and queries.
1577 * X86 general purpose registers
1579 GDB now supports reading/writing byte, word and double-word x86
1580 general purpose registers directly. This means you can use, say,
1581 $ah or $ax to refer, respectively, to the byte register AH and
1582 16-bit word register AX that are actually portions of the 32-bit
1583 register EAX or 64-bit register RAX.
1585 * The `commands' command now accepts a range of breakpoints to modify.
1586 A plain `commands' following a command that creates multiple
1587 breakpoints affects all the breakpoints set by that command. This
1588 applies to breakpoints set by `rbreak', and also applies when a
1589 single `break' command creates multiple breakpoints (e.g.,
1590 breakpoints on overloaded c++ functions).
1592 * The `rbreak' command now accepts a filename specification as part of
1593 its argument, limiting the functions selected by the regex to those
1594 in the specified file.
1596 * Support for remote debugging Windows and SymbianOS shared libraries
1597 from Unix hosts has been improved. Non Windows GDB builds now can
1598 understand target reported file names that follow MS-DOS based file
1599 system semantics, such as file names that include drive letters and
1600 use the backslash character as directory separator. This makes it
1601 possible to transparently use the "set sysroot" and "set
1602 solib-search-path" on Unix hosts to point as host copies of the
1603 target's shared libraries. See the new command "set
1604 target-file-system-kind" described below, and the "Commands to
1605 specify files" section in the user manual for more information.
1609 eval template, expressions...
1610 Convert the values of one or more expressions under the control
1611 of the string template to a command line, and call it.
1613 set target-file-system-kind unix|dos-based|auto
1614 show target-file-system-kind
1615 Set or show the assumed file system kind for target reported file
1618 save breakpoints <filename>
1619 Save all current breakpoint definitions to a file suitable for use
1620 in a later debugging session. To read the saved breakpoint
1621 definitions, use the `source' command.
1623 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1626 info static-tracepoint-markers
1627 Display information about static tracepoint markers in the target.
1629 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1630 Define a static tracepoint by probing a marker at the given
1631 function, line, address, or marker ID.
1635 Enable and disable observer mode.
1637 set may-write-registers on|off
1638 set may-write-memory on|off
1639 set may-insert-breakpoints on|off
1640 set may-insert-tracepoints on|off
1641 set may-insert-fast-tracepoints on|off
1642 set may-interrupt on|off
1643 Set individual permissions for GDB effects on the target. Note that
1644 some of these settings can have undesirable or surprising
1645 consequences, particularly when changed in the middle of a session.
1646 For instance, disabling the writing of memory can prevent
1647 breakpoints from being inserted, cause single-stepping to fail, or
1648 even crash your program, if you disable after breakpoints have been
1649 inserted. However, GDB should not crash.
1651 set record memory-query on|off
1652 show record memory-query
1653 Control whether to stop the inferior if memory changes caused
1654 by an instruction cannot be recorded.
1659 The disassemble command now supports "start,+length" form of two arguments.
1663 ** GDB now provides a new directory location, called the python directory,
1664 where Python scripts written for GDB can be installed. The location
1665 of that directory is <data-directory>/python, where <data-directory>
1666 is the GDB data directory. For more details, see section `Scripting
1667 GDB using Python' in the manual.
1669 ** The GDB Python API now has access to breakpoints, symbols, symbol
1670 tables, program spaces, inferiors, threads and frame's code blocks.
1671 Additionally, GDB Parameters can now be created from the API, and
1672 manipulated via set/show in the CLI.
1674 ** New functions gdb.target_charset, gdb.target_wide_charset,
1675 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1677 ** New exception gdb.GdbError.
1679 ** Pretty-printers are now also looked up in the current program space.
1681 ** Pretty-printers can now be individually enabled and disabled.
1683 ** GDB now looks for names of Python scripts to auto-load in a
1684 special section named `.debug_gdb_scripts', in addition to looking
1685 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1687 * Tracepoint actions were unified with breakpoint commands. In particular,
1688 there are no longer differences in "info break" output for breakpoints and
1689 tracepoints and the "commands" command can be used for both tracepoints and
1690 regular breakpoints.
1694 ARM Symbian arm*-*-symbianelf*
1696 * D language support.
1697 GDB now supports debugging programs written in the D programming
1700 * GDB now supports the extended ptrace interface for PowerPC which is
1701 available since Linux kernel version 2.6.34. This automatically enables
1702 any hardware breakpoints and additional hardware watchpoints available in
1703 the processor. The old ptrace interface exposes just one hardware
1704 watchpoint and no hardware breakpoints.
1706 * GDB is now able to use the Data Value Compare (DVC) register available on
1707 embedded PowerPC processors to implement in hardware simple watchpoint
1708 conditions of the form:
1710 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1712 This works in native GDB running on Linux kernels with the extended ptrace
1713 interface mentioned above.
1715 *** Changes in GDB 7.1
1719 ** Namespace Support
1721 GDB now supports importing of namespaces in C++. This enables the
1722 user to inspect variables from imported namespaces. Support for
1723 namepace aliasing has also been added. So, if a namespace is
1724 aliased in the current scope (e.g. namepace C=A; ) the user can
1725 print variables using the alias (e.g. (gdb) print C::x).
1729 All known bugs relating to the printing of virtual base class were
1730 fixed. It is now possible to call overloaded static methods using a
1735 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1736 and reinterpret_cast<> are now handled by the C++ expression parser.
1740 Xilinx MicroBlaze microblaze-*-*
1745 Xilinx MicroBlaze microblaze
1748 * Multi-program debugging.
1750 GDB now has support for multi-program (a.k.a. multi-executable or
1751 multi-exec) debugging. This allows for debugging multiple inferiors
1752 simultaneously each running a different program under the same GDB
1753 session. See "Debugging Multiple Inferiors and Programs" in the
1754 manual for more information. This implied some user visible changes
1755 in the multi-inferior support. For example, "info inferiors" now
1756 lists inferiors that are not running yet or that have exited
1757 already. See also "New commands" and "New options" below.
1759 * New tracing features
1761 GDB's tracepoint facility now includes several new features:
1763 ** Trace state variables
1765 GDB tracepoints now include support for trace state variables, which
1766 are variables managed by the target agent during a tracing
1767 experiment. They are useful for tracepoints that trigger each
1768 other, so for instance one tracepoint can count hits in a variable,
1769 and then a second tracepoint has a condition that is true when the
1770 count reaches a particular value. Trace state variables share the
1771 $-syntax of GDB convenience variables, and can appear in both
1772 tracepoint actions and condition expressions. Use the "tvariable"
1773 command to create, and "info tvariables" to view; see "Trace State
1774 Variables" in the manual for more detail.
1778 GDB now includes an option for defining fast tracepoints, which
1779 targets may implement more efficiently, such as by installing a jump
1780 into the target agent rather than a trap instruction. The resulting
1781 speedup can be by two orders of magnitude or more, although the
1782 tradeoff is that some program locations on some target architectures
1783 might not allow fast tracepoint installation, for instance if the
1784 instruction to be replaced is shorter than the jump. To request a
1785 fast tracepoint, use the "ftrace" command, with syntax identical to
1786 the regular trace command.
1788 ** Disconnected tracing
1790 It is now possible to detach GDB from the target while it is running
1791 a trace experiment, then reconnect later to see how the experiment
1792 is going. In addition, a new variable disconnected-tracing lets you
1793 tell the target agent whether to continue running a trace if the
1794 connection is lost unexpectedly.
1798 GDB now has the ability to save the trace buffer into a file, and
1799 then use that file as a target, similarly to you can do with
1800 corefiles. You can select trace frames, print data that was
1801 collected in them, and use tstatus to display the state of the
1802 tracing run at the moment that it was saved. To create a trace
1803 file, use "tsave <filename>", and to use it, do "target tfile
1806 ** Circular trace buffer
1808 You can ask the target agent to handle the trace buffer as a
1809 circular buffer, discarding the oldest trace frames to make room for
1810 newer ones, by setting circular-trace-buffer to on. This feature may
1811 not be available for all target agents.
1816 The disassemble command, when invoked with two arguments, now requires
1817 the arguments to be comma-separated.
1820 The info variables command now displays variable definitions. Files
1821 which only declare a variable are not shown.
1824 The source command is now capable of sourcing Python scripts.
1825 This feature is dependent on the debugger being build with Python
1828 Related to this enhancement is also the introduction of a new command
1829 "set script-extension" (see below).
1831 * New commands (for set/show, see "New options" below)
1833 record save [<FILENAME>]
1834 Save a file (in core file format) containing the process record
1835 execution log for replay debugging at a later time.
1837 record restore <FILENAME>
1838 Restore the process record execution log that was saved at an
1839 earlier time, for replay debugging.
1841 add-inferior [-copies <N>] [-exec <FILENAME>]
1844 clone-inferior [-copies <N>] [ID]
1845 Make a new inferior ready to execute the same program another
1846 inferior has loaded.
1851 maint info program-spaces
1852 List the program spaces loaded into GDB.
1854 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1855 show remote interrupt-sequence
1856 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1857 as the sequence to the remote target in order to interrupt the execution.
1858 Ctrl-C is a default. Some system prefers BREAK which is high level of
1859 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1860 Magic SysRq g. It is BREAK signal and character 'g'.
1862 set remote interrupt-on-connect [on | off]
1863 show remote interrupt-on-connect
1864 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1865 remote target when gdb connects to it. This is needed when you debug
1868 set remotebreak [on | off]
1870 Deprecated. Use "set/show remote interrupt-sequence" instead.
1872 tvariable $NAME [ = EXP ]
1873 Create or modify a trace state variable.
1876 List trace state variables and their values.
1878 delete tvariable $NAME ...
1879 Delete one or more trace state variables.
1882 Evaluate the given expressions without collecting anything into the
1883 trace buffer. (Valid in tracepoint actions only.)
1885 ftrace FN / FILE:LINE / *ADDR
1886 Define a fast tracepoint at the given function, line, or address.
1888 * New expression syntax
1890 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1891 GDB now parses 0b101010 identically with 42.
1895 set follow-exec-mode new|same
1896 show follow-exec-mode
1897 Control whether GDB reuses the same inferior across an exec call or
1898 creates a new one. This is useful to be able to restart the old
1899 executable after the inferior having done an exec call.
1901 set default-collect EXPR, ...
1902 show default-collect
1903 Define a list of expressions to be collected at each tracepoint.
1904 This is a useful way to ensure essential items are not overlooked,
1905 such as registers or a critical global variable.
1907 set disconnected-tracing
1908 show disconnected-tracing
1909 If set to 1, the target is instructed to continue tracing if it
1910 loses its connection to GDB. If 0, the target is to stop tracing
1913 set circular-trace-buffer
1914 show circular-trace-buffer
1915 If set to on, the target is instructed to use a circular trace buffer
1916 and discard the oldest trace frames instead of stopping the trace due
1917 to a full trace buffer. If set to off, the trace stops when the buffer
1918 fills up. Some targets may not support this.
1920 set script-extension off|soft|strict
1921 show script-extension
1922 If set to "off", the debugger does not perform any script language
1923 recognition, and all sourced files are assumed to be GDB scripts.
1924 If set to "soft" (the default), files are sourced according to
1925 filename extension, falling back to GDB scripts if the first
1927 If set to "strict", files are sourced according to filename extension.
1929 set ada trust-PAD-over-XVS on|off
1930 show ada trust-PAD-over-XVS
1931 If off, activate a workaround against a bug in the debugging information
1932 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1933 the GCC sources for more information about the GNAT encoding and
1934 PAD types in particular). It is always safe to set this option to
1935 off, but this introduces a slight performance penalty. The default
1938 * Python API Improvements
1940 ** GDB provides the new class gdb.LazyString. This is useful in
1941 some pretty-printing cases. The new method gdb.Value.lazy_string
1942 provides a simple way to create objects of this type.
1944 ** The fields returned by gdb.Type.fields now have an
1945 `is_base_class' attribute.
1947 ** The new method gdb.Type.range returns the range of an array type.
1949 ** The new method gdb.parse_and_eval can be used to parse and
1950 evaluate an expression.
1952 * New remote packets
1955 Define a trace state variable.
1958 Get the current value of a trace state variable.
1961 Set desired tracing behavior upon disconnection.
1964 Set the trace buffer to be linear or circular.
1967 Get data about the tracepoints currently in use.
1971 Process record now works correctly with hardware watchpoints.
1973 Multiple bug fixes have been made to the mips-irix port, making it
1974 much more reliable. In particular:
1975 - Debugging threaded applications is now possible again. Previously,
1976 GDB would hang while starting the program, or while waiting for
1977 the program to stop at a breakpoint.
1978 - Attaching to a running process no longer hangs.
1979 - An error occurring while loading a core file has been fixed.
1980 - Changing the value of the PC register now works again. This fixes
1981 problems observed when using the "jump" command, or when calling
1982 a function from GDB, or even when assigning a new value to $pc.
1983 - With the "finish" and "return" commands, the return value for functions
1984 returning a small array is now correctly printed.
1985 - It is now possible to break on shared library code which gets executed
1986 during a shared library init phase (code executed while executing
1987 their .init section). Previously, the breakpoint would have no effect.
1988 - GDB is now able to backtrace through the signal handler for
1989 non-threaded programs.
1991 PIE (Position Independent Executable) programs debugging is now supported.
1992 This includes debugging execution of PIC (Position Independent Code) shared
1993 libraries although for that, it should be possible to run such libraries as an
1996 *** Changes in GDB 7.0
1998 * GDB now has an interface for JIT compilation. Applications that
1999 dynamically generate code can create symbol files in memory and register
2000 them with GDB. For users, the feature should work transparently, and
2001 for JIT developers, the interface is documented in the GDB manual in the
2002 "JIT Compilation Interface" chapter.
2004 * Tracepoints may now be conditional. The syntax is as for
2005 breakpoints; either an "if" clause appended to the "trace" command,
2006 or the "condition" command is available. GDB sends the condition to
2007 the target for evaluation using the same bytecode format as is used
2008 for tracepoint actions.
2010 * The disassemble command now supports: an optional /r modifier, print the
2011 raw instructions in hex as well as in symbolic form, and an optional /m
2012 modifier to print mixed source+assembly.
2014 * Process record and replay
2016 In a architecture environment that supports ``process record and
2017 replay'', ``process record and replay'' target can record a log of
2018 the process execution, and replay it with both forward and reverse
2021 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2022 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2023 set execution-direction {forward|reverse}, for targets that support
2026 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2027 feature is available with a native GDB running on kernel version
2030 * GDB now has support for multi-byte and wide character sets on the
2031 target. Strings whose character type is wchar_t, char16_t, or
2032 char32_t are now correctly printed. GDB supports wide- and unicode-
2033 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2034 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2035 `printf'. This feature requires iconv to work properly; if your
2036 system does not have a working iconv, GDB can use GNU libiconv. See
2037 the installation instructions for more information.
2039 * GDB now supports automatic retrieval of shared library files from
2040 remote targets. To use this feature, specify a system root that begins
2041 with the `remote:' prefix, either via the `set sysroot' command or via
2042 the `--with-sysroot' configure-time option.
2044 * "info sharedlibrary" now takes an optional regex of libraries to show,
2045 and it now reports if a shared library has no debugging information.
2047 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2048 now complete on file names.
2050 * When completing in expressions, gdb will attempt to limit
2051 completions to allowable structure or union fields, where appropriate.
2052 For instance, consider:
2054 # struct example { int f1; double f2; };
2055 # struct example variable;
2058 If the user types TAB at the end of this command line, the available
2059 completions will be "f1" and "f2".
2061 * Inlined functions are now supported. They show up in backtraces, and
2062 the "step", "next", and "finish" commands handle them automatically.
2064 * GDB now supports the token-splicing (##) and stringification (#)
2065 operators when expanding macros. It also supports variable-arity
2068 * GDB now supports inspecting extra signal information, exported by
2069 the new $_siginfo convenience variable. The feature is currently
2070 implemented on linux ARM, i386 and amd64.
2072 * GDB can now display the VFP floating point registers and NEON vector
2073 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2074 can provide these registers (requires Linux 2.6.30 or later). Remote
2075 and simulator targets may also provide them.
2077 * New remote packets
2080 Search memory for a sequence of bytes.
2083 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2084 operation over reliable transport links. Use of this packet is
2085 controlled by the `set remote noack-packet' command.
2088 Kill the process with the specified process ID. Use this in preference
2089 to `k' when multiprocess protocol extensions are supported.
2092 Obtains additional operating system information
2096 Read or write additional signal information.
2098 * Removed remote protocol undocumented extension
2100 An undocumented extension to the remote protocol's `S' stop reply
2101 packet that permited the stub to pass a process id was removed.
2102 Remote servers should use the `T' stop reply packet instead.
2104 * GDB now supports multiple function calling conventions according to the
2105 DWARF-2 DW_AT_calling_convention function attribute.
2107 * The SH target utilizes the aforementioned change to distinguish between gcc
2108 and Renesas calling convention. It also adds the new CLI commands
2109 `set/show sh calling-convention'.
2111 * GDB can now read compressed debug sections, as produced by GNU gold
2112 with the --compress-debug-sections=zlib flag.
2114 * 64-bit core files are now supported on AIX.
2116 * Thread switching is now supported on Tru64.
2118 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2119 which will be allocated using malloc later in program execution.
2121 * The qXfer:libraries:read remote procotol packet now allows passing a
2122 list of section offsets.
2124 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2125 conditions handling signals delivered during attach or thread creation
2126 have also been fixed.
2128 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2129 From the user's standpoint, all unqualified instances of True and False
2130 are treated as the standard definitions, regardless of context.
2132 * GDB now parses C++ symbol and type names more flexibly. For
2135 template<typename T> class C { };
2138 GDB will now correctly handle all of:
2140 ptype C<char const *>
2141 ptype C<char const*>
2142 ptype C<const char *>
2143 ptype C<const char*>
2145 * New features in the GDB remote stub, gdbserver
2147 - The "--wrapper" command-line argument tells gdbserver to use a
2148 wrapper program to launch programs for debugging.
2150 - On PowerPC and S/390 targets, it is now possible to use a single
2151 gdbserver executable to debug both 32-bit and 64-bit programs.
2152 (This requires gdbserver itself to be built as a 64-bit executable.)
2154 - gdbserver uses the new noack protocol mode for TCP connections to
2155 reduce communications latency, if also supported and enabled in GDB.
2157 - Support for the sparc64-linux-gnu target is now included in
2160 - The amd64-linux build of gdbserver now supports debugging both
2161 32-bit and 64-bit programs.
2163 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2164 now support hardware watchpoints, and will use them automatically
2169 GDB now has support for scripting using Python. Whether this is
2170 available is determined at configure time.
2172 New GDB commands can now be written in Python.
2174 * Ada tasking support
2176 Ada tasks can now be inspected in GDB. The following commands have
2180 Print the list of Ada tasks.
2182 Print detailed information about task number N.
2184 Print the task number of the current task.
2186 Switch the context of debugging to task number N.
2188 * Support for user-defined prefixed commands. The "define" command can
2189 add new commands to existing prefixes, e.g. "target".
2191 * Multi-inferior, multi-process debugging.
2193 GDB now has generalized support for multi-inferior debugging. See
2194 "Debugging Multiple Inferiors" in the manual for more information.
2195 Although availability still depends on target support, the command
2196 set is more uniform now. The GNU/Linux specific multi-forks support
2197 has been migrated to this new framework. This implied some user
2198 visible changes; see "New commands" and also "Removed commands"
2201 * Target descriptions can now describe the target OS ABI. See the
2202 "Target Description Format" section in the user manual for more
2205 * Target descriptions can now describe "compatible" architectures
2206 to indicate that the target can execute applications for a different
2207 architecture in addition to those for the main target architecture.
2208 See the "Target Description Format" section in the user manual for
2211 * Multi-architecture debugging.
2213 GDB now includes general supports for debugging applications on
2214 hybrid systems that use more than one single processor architecture
2215 at the same time. Each such hybrid architecture still requires
2216 specific support to be added. The only hybrid architecture supported
2217 in this version of GDB is the Cell Broadband Engine.
2219 * GDB now supports integrated debugging of Cell/B.E. applications that
2220 use both the PPU and SPU architectures. To enable support for hybrid
2221 Cell/B.E. debugging, you need to configure GDB to support both the
2222 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2223 --enable-targets configure option.
2225 * Non-stop mode debugging.
2227 For some targets, GDB now supports an optional mode of operation in
2228 which you can examine stopped threads while other threads continue
2229 to execute freely. This is referred to as non-stop mode, with the
2230 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2231 section in the user manual for more information.
2233 To be able to support remote non-stop debugging, a remote stub needs
2234 to implement the non-stop mode remote protocol extensions, as
2235 described in the "Remote Non-Stop" section of the user manual. The
2236 GDB remote stub, gdbserver, has been adjusted to support these
2237 extensions on linux targets.
2239 * New commands (for set/show, see "New options" below)
2241 catch syscall [NAME(S) | NUMBER(S)]
2242 Catch system calls. Arguments, which should be names of system
2243 calls or their numbers, mean catch only those syscalls. Without
2244 arguments, every syscall will be caught. When the inferior issues
2245 any of the specified syscalls, GDB will stop and announce the system
2246 call, both when it is called and when its call returns. This
2247 feature is currently available with a native GDB running on the
2248 Linux Kernel, under the following architectures: x86, x86_64,
2249 PowerPC and PowerPC64.
2251 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2253 Search memory for a sequence of bytes.
2255 maint set python print-stack
2256 maint show python print-stack
2257 Show a stack trace when an error is encountered in a Python script.
2260 Invoke CODE by passing it to the Python interpreter.
2265 These allow macros to be defined, undefined, and listed
2269 Show operating system information about processes.
2272 List the inferiors currently under GDB's control.
2275 Switch focus to inferior number NUM.
2278 Detach from inferior number NUM.
2281 Kill inferior number NUM.
2285 set spu stop-on-load
2286 show spu stop-on-load
2287 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2289 set spu auto-flush-cache
2290 show spu auto-flush-cache
2291 Control whether to automatically flush the software-managed cache
2292 during Cell/B.E. debugging.
2294 set sh calling-convention
2295 show sh calling-convention
2296 Control the calling convention used when calling SH target functions.
2299 show debug timestamp
2300 Control display of timestamps with GDB debugging output.
2302 set disassemble-next-line
2303 show disassemble-next-line
2304 Control display of disassembled source lines or instructions when
2307 set remote noack-packet
2308 show remote noack-packet
2309 Set/show the use of remote protocol QStartNoAckMode packet. See above
2310 under "New remote packets."
2312 set remote query-attached-packet
2313 show remote query-attached-packet
2314 Control use of remote protocol `qAttached' (query-attached) packet.
2316 set remote read-siginfo-object
2317 show remote read-siginfo-object
2318 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2321 set remote write-siginfo-object
2322 show remote write-siginfo-object
2323 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2326 set remote reverse-continue
2327 show remote reverse-continue
2328 Control use of remote protocol 'bc' (reverse-continue) packet.
2330 set remote reverse-step
2331 show remote reverse-step
2332 Control use of remote protocol 'bs' (reverse-step) packet.
2334 set displaced-stepping
2335 show displaced-stepping
2336 Control displaced stepping mode. Displaced stepping is a way to
2337 single-step over breakpoints without removing them from the debuggee.
2338 Also known as "out-of-line single-stepping".
2341 show debug displaced
2342 Control display of debugging info for displaced stepping.
2344 maint set internal-error
2345 maint show internal-error
2346 Control what GDB does when an internal error is detected.
2348 maint set internal-warning
2349 maint show internal-warning
2350 Control what GDB does when an internal warning is detected.
2355 Use a wrapper program to launch programs for debugging.
2357 set multiple-symbols (all|ask|cancel)
2358 show multiple-symbols
2359 The value of this variable can be changed to adjust the debugger behavior
2360 when an expression or a breakpoint location contains an ambiguous symbol
2361 name (an overloaded function name, for instance).
2363 set breakpoint always-inserted
2364 show breakpoint always-inserted
2365 Keep breakpoints always inserted in the target, as opposed to inserting
2366 them when resuming the target, and removing them when the target stops.
2367 This option can improve debugger performance on slow remote targets.
2369 set arm fallback-mode (arm|thumb|auto)
2370 show arm fallback-mode
2371 set arm force-mode (arm|thumb|auto)
2373 These commands control how ARM GDB determines whether instructions
2374 are ARM or Thumb. The default for both settings is auto, which uses
2375 the current CPSR value for instructions without symbols; previous
2376 versions of GDB behaved as if "set arm fallback-mode arm".
2378 set disable-randomization
2379 show disable-randomization
2380 Standalone programs run with the virtual address space randomization enabled
2381 by default on some platforms. This option keeps the addresses stable across
2382 multiple debugging sessions.
2386 Control whether other threads are stopped or not when some thread hits
2391 Requests that asynchronous execution is enabled in the target, if available.
2392 In this case, it's possible to resume target in the background, and interact
2393 with GDB while the target is running. "show target-async" displays the
2394 current state of asynchronous execution of the target.
2396 set target-wide-charset
2397 show target-wide-charset
2398 The target-wide-charset is the name of the character set that GDB
2399 uses when printing characters whose type is wchar_t.
2401 set tcp auto-retry (on|off)
2403 set tcp connect-timeout
2404 show tcp connect-timeout
2405 These commands allow GDB to retry failed TCP connections to a remote stub
2406 with a specified timeout period; this is useful if the stub is launched
2407 in parallel with GDB but may not be ready to accept connections immediately.
2409 set libthread-db-search-path
2410 show libthread-db-search-path
2411 Control list of directories which GDB will search for appropriate
2414 set schedule-multiple (on|off)
2415 show schedule-multiple
2416 Allow GDB to resume all threads of all processes or only threads of
2417 the current process.
2421 Use more aggressive caching for accesses to the stack. This improves
2422 performance of remote debugging (particularly backtraces) without
2423 affecting correctness.
2425 set interactive-mode (on|off|auto)
2426 show interactive-mode
2427 Control whether GDB runs in interactive mode (on) or not (off).
2428 When in interactive mode, GDB waits for the user to answer all
2429 queries. Otherwise, GDB does not wait and assumes the default
2430 answer. When set to auto (the default), GDB determines which
2431 mode to use based on the stdin settings.
2436 For program forks, this is replaced by the new more generic `info
2437 inferiors' command. To list checkpoints, you can still use the
2438 `info checkpoints' command, which was an alias for the `info forks'
2442 Replaced by the new `inferior' command. To switch between
2443 checkpoints, you can still use the `restart' command, which was an
2444 alias for the `fork' command.
2447 This is removed, since some targets don't have a notion of
2448 processes. To switch between processes, you can still use the
2449 `inferior' command using GDB's own inferior number.
2452 For program forks, this is replaced by the new more generic `kill
2453 inferior' command. To delete a checkpoint, you can still use the
2454 `delete checkpoint' command, which was an alias for the `delete
2458 For program forks, this is replaced by the new more generic `detach
2459 inferior' command. To detach a checkpoint, you can still use the
2460 `detach checkpoint' command, which was an alias for the `detach
2463 * New native configurations
2465 x86/x86_64 Darwin i[34567]86-*-darwin*
2467 x86_64 MinGW x86_64-*-mingw*
2471 Lattice Mico32 lm32-*
2472 x86 DICOS i[34567]86-*-dicos*
2473 x86_64 DICOS x86_64-*-dicos*
2476 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2477 (mingw32ce) debugging.
2483 These commands were actually not implemented on any target.
2485 *** Changes in GDB 6.8
2487 * New native configurations
2489 NetBSD/hppa hppa*-*netbsd*
2490 Xtensa GNU/Linux xtensa*-*-linux*
2494 NetBSD/hppa hppa*-*-netbsd*
2495 Xtensa GNU/Lunux xtensa*-*-linux*
2497 * Change in command line behavior -- corefiles vs. process ids.
2499 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2500 attaching to process NUMBER fails, GDB no longer attempts to open a
2501 core file named NUMBER. Attaching to a program using the -c option
2502 is no longer supported. Instead, use the '-p' or '--pid' options.
2504 * GDB can now be built as a native debugger for debugging Windows x86
2505 (mingw32) Portable Executable (PE) programs.
2507 * Pending breakpoints no longer change their number when their address
2510 * GDB now supports breakpoints with multiple locations,
2511 including breakpoints on C++ constructors, inside C++ templates,
2512 and in inlined functions.
2514 * GDB's ability to debug optimized code has been improved. GDB more
2515 accurately identifies function bodies and lexical blocks that occupy
2516 more than one contiguous range of addresses.
2518 * Target descriptions can now describe registers for PowerPC.
2520 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2521 registers on PowerPC targets.
2523 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2524 targets even when the libthread_db library is not available.
2526 * The GDB remote stub, gdbserver, now supports the new file transfer
2527 commands (remote put, remote get, and remote delete).
2529 * The GDB remote stub, gdbserver, now supports run and attach in
2530 extended-remote mode.
2532 * hppa*64*-*-hpux11* target broken
2533 The debugger is unable to start a program and fails with the following
2534 error: "Error trying to get information about dynamic linker".
2535 The gdb-6.7 release is also affected.
2537 * GDB now supports the --enable-targets= configure option to allow
2538 building a single GDB executable that supports multiple remote
2539 target architectures.
2541 * GDB now supports debugging C and C++ programs which use the
2542 Decimal Floating Point extension. In addition, the PowerPC target
2543 now has a set of pseudo-registers to inspect decimal float values
2544 stored in two consecutive float registers.
2546 * The -break-insert MI command can optionally create pending
2549 * Improved support for debugging Ada
2550 Many improvements to the Ada language support have been made. These
2552 - Better support for Ada2005 interface types
2553 - Improved handling of arrays and slices in general
2554 - Better support for Taft-amendment types
2555 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2557 - Improved command completion in Ada
2560 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2565 set print frame-arguments (all|scalars|none)
2566 show print frame-arguments
2567 The value of this variable can be changed to control which argument
2568 values should be printed by the debugger when displaying a frame.
2573 Transfer files to and from a remote target, and delete remote files.
2580 Transfer files to and from a remote target, and delete remote files.
2582 * New remote packets
2589 Open, close, read, write, and delete files on the remote system.
2592 Attach to an existing process on the remote system, in extended-remote
2596 Run a new process on the remote system, in extended-remote mode.
2598 *** Changes in GDB 6.7
2600 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2601 bfd, libiberty and opcodes, as revealed by static analysis donated by
2602 Coverity, Inc. (http://scan.coverity.com).
2604 * When looking up multiply-defined global symbols, GDB will now prefer the
2605 symbol definition in the current shared library if it was built using the
2606 -Bsymbolic linker option.
2608 * When the Text User Interface (TUI) is not configured, GDB will now
2609 recognize the -tui command-line option and print a message that the TUI
2612 * The GDB remote stub, gdbserver, now has lower overhead for high
2613 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2615 * GDB for MIPS targets now autodetects whether a remote target provides
2616 32-bit or 64-bit register values.
2618 * Support for C++ member pointers has been improved.
2620 * GDB now understands XML target descriptions, which specify the
2621 target's overall architecture. GDB can read a description from
2622 a local file or over the remote serial protocol.
2624 * Vectors of single-byte data use a new integer type which is not
2625 automatically displayed as character or string data.
2627 * The /s format now works with the print command. It displays
2628 arrays of single-byte integers and pointers to single-byte integers
2631 * Target descriptions can now describe target-specific registers,
2632 for architectures which have implemented the support (currently
2633 only ARM, M68K, and MIPS).
2635 * GDB and the GDB remote stub, gdbserver, now support the XScale
2638 * The GDB remote stub, gdbserver, has been updated to support
2639 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2640 has been rewritten to use the standard GDB remote protocol.
2642 * GDB can now step into C++ functions which are called through thunks.
2644 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2646 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2647 layout. It also supports a TextSeg= and DataSeg= response when only
2648 segment base addresses (rather than offsets) are available.
2650 * The /i format now outputs any trailing branch delay slot instructions
2651 immediately following the last instruction within the count specified.
2653 * The GDB remote protocol "T" stop reply packet now supports a
2654 "library" response. Combined with the new "qXfer:libraries:read"
2655 packet, this response allows GDB to debug shared libraries on targets
2656 where the operating system manages the list of loaded libraries (e.g.
2657 Windows and SymbianOS).
2659 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2660 (DLLs) on Windows and Windows CE targets.
2662 * GDB now supports a faster verification that a .debug file matches its binary
2663 according to its build-id signature, if the signature is present.
2669 Enable or disable hardware flow control (RTS/CTS) on the serial port
2670 when debugging using remote targets.
2672 set mem inaccessible-by-default
2673 show mem inaccessible-by-default
2674 If the target supplies a memory map, for instance via the remote
2675 protocol's "qXfer:memory-map:read" packet, setting this variable
2676 prevents GDB from accessing memory outside the memory map. This
2677 is useful for targets with memory mapped registers or which react
2678 badly to accesses of unmapped address space.
2680 set breakpoint auto-hw
2681 show breakpoint auto-hw
2682 If the target supplies a memory map, for instance via the remote
2683 protocol's "qXfer:memory-map:read" packet, setting this variable
2684 lets GDB use hardware breakpoints automatically for memory regions
2685 where it can not use software breakpoints. This covers both the
2686 "break" command and internal breakpoints used for other commands
2687 including "next" and "finish".
2690 catch exception unhandled
2691 Stop the program execution when Ada exceptions are raised.
2694 Stop the program execution when an Ada assertion failed.
2698 Set an alternate system root for target files. This is a more
2699 general version of "set solib-absolute-prefix", which is now
2700 an alias to "set sysroot".
2703 Provide extended SPU facility status information. This set of
2704 commands is available only when debugging the Cell/B.E. SPU
2707 * New native configurations
2709 OpenBSD/sh sh*-*openbsd*
2712 unset tdesc filename
2714 Use the specified local file as an XML target description, and do
2715 not query the target for its built-in description.
2719 OpenBSD/sh sh*-*-openbsd*
2720 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2721 Toshiba Media Processor mep-elf
2723 * New remote packets
2726 Ignore the specified signals; pass them directly to the debugged program
2727 without stopping other threads or reporting them to GDB.
2729 qXfer:features:read:
2730 Read an XML target description from the target, which describes its
2735 Read or write contents of an spufs file on the target system. These
2736 packets are available only on the Cell/B.E. SPU architecture.
2738 qXfer:libraries:read:
2739 Report the loaded shared libraries. Combined with new "T" packet
2740 response, this packet allows GDB to debug shared libraries on
2741 targets where the operating system manages the list of loaded
2742 libraries (e.g. Windows and SymbianOS).
2746 Support for these obsolete configurations has been removed.
2754 i[34567]86-*-lynxos*
2755 i[34567]86-*-netware*
2756 i[34567]86-*-sco3.2v5*
2757 i[34567]86-*-sco3.2v4*
2759 i[34567]86-*-sysv4.2*
2762 i[34567]86-*-unixware2*
2763 i[34567]86-*-unixware*
2772 * Other removed features
2779 Various m68k-only ROM monitors.
2786 Various Renesas ROM monitors and debugging interfaces for SH and
2791 Support for a Macraigor serial interface to on-chip debugging.
2792 GDB does not directly support the newer parallel or USB
2797 A debug information format. The predecessor to DWARF 2 and
2798 DWARF 3, which are still supported.
2800 Support for the HP aCC compiler on HP-UX/PA-RISC
2802 SOM-encapsulated symbolic debugging information, automatic
2803 invocation of pxdb, and the aCC custom C++ ABI. This does not
2804 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2805 with aCC can still be debugged on an assembly level.
2807 MIPS ".pdr" sections
2809 A MIPS-specific format used to describe stack frame layout
2810 in debugging information.
2814 GDB could work with an older version of Guile to debug
2815 the interpreter and Scheme programs running in it.
2817 set mips stack-arg-size
2818 set mips saved-gpreg-size
2820 Use "set mips abi" to control parameter passing for MIPS.
2822 *** Changes in GDB 6.6
2827 Cell Broadband Engine SPU spu-elf
2829 * GDB can now be configured as a cross-debugger targeting native Windows
2830 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2831 running on a Windows system over TCP/IP to debug Windows programs.
2833 * The GDB remote stub, gdbserver, has been updated to support Windows and
2834 Cygwin debugging. Both single-threaded and multi-threaded programs are
2837 * The "set trust-readonly-sections" command works again. This command was
2838 broken in GDB 6.3, 6.4, and 6.5.
2840 * The "load" command now supports writing to flash memory, if the remote
2841 stub provides the required support.
2843 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2844 longer requires symbolic debug information (e.g. DWARF-2).
2849 unset substitute-path
2850 show substitute-path
2851 Manage a list of substitution rules that GDB uses to rewrite the name
2852 of the directories where the sources are located. This can be useful
2853 for instance when the sources were moved to a different location
2854 between compilation and debugging.
2858 Print each CLI command as it is executed. Each command is prefixed with
2859 a number of `+' symbols representing the nesting depth.
2860 The source command now has a `-v' option to enable the same feature.
2864 The ARM Demon monitor support (RDP protocol, "target rdp").
2866 Kernel Object Display, an embedded debugging feature which only worked with
2867 an obsolete version of Cisco IOS.
2869 The 'set download-write-size' and 'show download-write-size' commands.
2871 * New remote packets
2874 Tell a stub about GDB client features, and request remote target features.
2875 The first feature implemented is PacketSize, which allows the target to
2876 specify the size of packets it can handle - to minimize the number of
2877 packets required and improve performance when connected to a remote
2881 Fetch an OS auxilliary vector from the remote stub. This packet is a
2882 more efficient replacement for qPart:auxv:read.
2884 qXfer:memory-map:read:
2885 Fetch a memory map from the remote stub, including information about
2886 RAM, ROM, and flash memory devices.
2891 Erase and program a flash memory device.
2893 * Removed remote packets
2896 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2897 used it, and only gdbserver implemented it.
2899 *** Changes in GDB 6.5
2903 Renesas M32C/M16C m32c-elf
2905 Morpho Technologies ms1 ms1-elf
2909 init-if-undefined Initialize a convenience variable, but
2910 only if it doesn't already have a value.
2912 The following commands are presently only implemented for native GNU/Linux:
2914 checkpoint Save a snapshot of the program state.
2916 restart <n> Return the program state to a
2917 previously saved state.
2919 info checkpoints List currently saved checkpoints.
2921 delete-checkpoint <n> Delete a previously saved checkpoint.
2923 set|show detach-on-fork Tell gdb whether to detach from a newly
2924 forked process, or to keep debugging it.
2926 info forks List forks of the user program that
2927 are available to be debugged.
2929 fork <n> Switch to debugging one of several
2930 forks of the user program that are
2931 available to be debugged.
2933 delete-fork <n> Delete a fork from the list of forks
2934 that are available to be debugged (and
2935 kill the forked process).
2937 detach-fork <n> Delete a fork from the list of forks
2938 that are available to be debugged (and
2939 allow the process to continue).
2943 Morpho Technologies ms2 ms1-elf
2945 * Improved Windows host support
2947 GDB now builds as a cross debugger hosted on i686-mingw32, including
2948 native console support, and remote communications using either
2949 network sockets or serial ports.
2951 * Improved Modula-2 language support
2953 GDB can now print most types in the Modula-2 syntax. This includes:
2954 basic types, set types, record types, enumerated types, range types,
2955 pointer types and ARRAY types. Procedure var parameters are correctly
2956 printed and hexadecimal addresses and character constants are also
2957 written in the Modula-2 syntax. Best results can be obtained by using
2958 GNU Modula-2 together with the -gdwarf-2 command line option.
2962 The ARM rdi-share module.
2964 The Netware NLM debug server.
2966 *** Changes in GDB 6.4
2968 * New native configurations
2970 OpenBSD/arm arm*-*-openbsd*
2971 OpenBSD/mips64 mips64-*-openbsd*
2975 Morpho Technologies ms1 ms1-elf
2977 * New command line options
2979 --batch-silent As for --batch, but totally silent.
2980 --return-child-result The debugger will exist with the same value
2981 the child (debugged) program exited with.
2982 --eval-command COMMAND, -ex COMMAND
2983 Execute a single GDB CLI command. This may be
2984 specified multiple times and in conjunction
2985 with the --command (-x) option.
2987 * Deprecated commands removed
2989 The following commands, that were deprecated in 2000, have been
2993 set|show arm disassembly-flavor set|show arm disassembler
2994 othernames set arm disassembler
2995 set|show remotedebug set|show debug remote
2996 set|show archdebug set|show debug arch
2997 set|show eventdebug set|show debug event
3000 * New BSD user-level threads support
3002 It is now possible to debug programs using the user-level threads
3003 library on OpenBSD and FreeBSD. Currently supported (target)
3006 FreeBSD/amd64 x86_64-*-freebsd*
3007 FreeBSD/i386 i386-*-freebsd*
3008 OpenBSD/i386 i386-*-openbsd*
3010 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3011 are not yet supported.
3013 * New support for Matsushita MN10300 w/sim added
3014 (Work in progress). mn10300-elf.
3016 * REMOVED configurations and files
3018 VxWorks and the XDR protocol *-*-vxworks
3019 Motorola MCORE mcore-*-*
3020 National Semiconductor NS32000 ns32k-*-*
3022 * New "set print array-indexes" command
3024 After turning this setting "on", GDB prints the index of each element
3025 when displaying arrays. The default is "off" to preserve the previous
3028 * VAX floating point support
3030 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3032 * User-defined command support
3034 In addition to using $arg0..$arg9 for argument passing, it is now possible
3035 to use $argc to determine now many arguments have been passed. See the
3036 section on user-defined commands in the user manual for more information.
3038 *** Changes in GDB 6.3:
3040 * New command line option
3042 GDB now accepts -l followed by a number to set the timeout for remote
3045 * GDB works with GCC -feliminate-dwarf2-dups
3047 GDB now supports a more compact representation of DWARF-2 debug
3048 information using DW_FORM_ref_addr references. These are produced
3049 by GCC with the option -feliminate-dwarf2-dups and also by some
3050 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3051 to use -feliminate-dwarf2-dups.
3053 * Internationalization
3055 When supported by the host system, GDB will be built with
3056 internationalization (libintl). The task of marking up the sources is
3057 continued, we're looking forward to our first translation.
3061 Initial support for debugging programs compiled with the GNAT
3062 implementation of the Ada programming language has been integrated
3063 into GDB. In this release, support is limited to expression evaluation.
3065 * New native configurations
3067 GNU/Linux/m32r m32r-*-linux-gnu
3071 GDB's remote protocol now includes support for the 'p' packet. This
3072 packet is used to fetch individual registers from a remote inferior.
3074 * END-OF-LIFE registers[] compatibility module
3076 GDB's internal register infrastructure has been completely rewritten.
3077 The new infrastructure making possible the implementation of key new
3078 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3081 GDB 6.3 will be the last release to include the the registers[]
3082 compatibility module that allowed out-of-date configurations to
3083 continue to work. This change directly impacts the following
3093 powerpc bdm protocol
3095 Unless there is activity to revive these configurations, they will be
3096 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3098 * OBSOLETE configurations and files
3100 Configurations that have been declared obsolete in this release have
3101 been commented out. Unless there is activity to revive these
3102 configurations, the next release of GDB will have their sources
3103 permanently REMOVED.
3112 *** Changes in GDB 6.2.1:
3114 * MIPS `break main; run' gave an heuristic-fence-post warning
3116 When attempting to run even a simple program, a warning about
3117 heuristic-fence-post being hit would be reported. This problem has
3120 * MIPS IRIX 'long double' crashed GDB
3122 When examining a long double variable, GDB would get a segmentation
3123 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3124 IRIX long double values).
3128 A bug in the VAX stack code was causing problems with the "next"
3129 command. This problem has been fixed.
3131 *** Changes in GDB 6.2:
3133 * Fix for ``many threads''
3135 On GNU/Linux systems that use the NPTL threads library, a program
3136 rapidly creating and deleting threads would confuse GDB leading to the
3139 ptrace: No such process.
3140 thread_db_get_info: cannot get thread info: generic error
3142 This problem has been fixed.
3144 * "-async" and "-noasync" options removed.
3146 Support for the broken "-noasync" option has been removed (it caused
3149 * New ``start'' command.
3151 This command runs the program until the begining of the main procedure.
3153 * New BSD Kernel Data Access Library (libkvm) interface
3155 Using ``target kvm'' it is now possible to debug kernel core dumps and
3156 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3157 platforms. Currently supported (native-only) configurations are:
3159 FreeBSD/amd64 x86_64-*-freebsd*
3160 FreeBSD/i386 i?86-*-freebsd*
3161 NetBSD/i386 i?86-*-netbsd*
3162 NetBSD/m68k m68*-*-netbsd*
3163 NetBSD/sparc sparc-*-netbsd*
3164 OpenBSD/amd64 x86_64-*-openbsd*
3165 OpenBSD/i386 i?86-*-openbsd*
3166 OpenBSD/m68k m68*-openbsd*
3167 OpenBSD/sparc sparc-*-openbsd*
3169 * Signal trampoline code overhauled
3171 Many generic problems with GDB's signal handling code have been fixed.
3172 These include: backtraces through non-contiguous stacks; recognition
3173 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3174 call; backtrace through a signal trampoline; step into and out of
3175 signal handlers; and single-stepping in the signal trampoline.
3177 Please note that kernel bugs are a limiting factor here. These
3178 features have been shown to work on an s390 GNU/Linux system that
3179 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3181 * Cygwin support for DWARF 2 added.
3183 * New native configurations
3185 GNU/Linux/hppa hppa*-*-linux*
3186 OpenBSD/hppa hppa*-*-openbsd*
3187 OpenBSD/m68k m68*-*-openbsd*
3188 OpenBSD/m88k m88*-*-openbsd*
3189 OpenBSD/powerpc powerpc-*-openbsd*
3190 NetBSD/vax vax-*-netbsd*
3191 OpenBSD/vax vax-*-openbsd*
3193 * END-OF-LIFE frame compatibility module
3195 GDB's internal frame infrastructure has been completely rewritten.
3196 The new infrastructure making it possible to support key new features
3197 including DWARF 2 Call Frame Information. To aid in the task of
3198 migrating old configurations to this new infrastructure, a
3199 compatibility module, that allowed old configurations to continue to
3200 work, was also included.
3202 GDB 6.2 will be the last release to include this frame compatibility
3203 module. This change directly impacts the following configurations:
3213 Unless there is activity to revive these configurations, they will be
3214 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3216 * REMOVED configurations and files
3218 Sun 3, running SunOS 3 m68*-*-sunos3*
3219 Sun 3, running SunOS 4 m68*-*-sunos4*
3220 Sun 2, running SunOS 3 m68000-*-sunos3*
3221 Sun 2, running SunOS 4 m68000-*-sunos4*
3222 Motorola 680x0 running LynxOS m68*-*-lynxos*
3223 AT&T 3b1/Unix pc m68*-att-*
3224 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3225 decstation mips-dec-* mips-little-*
3226 riscos mips-*-riscos* mips-*-sysv*
3227 sonymips mips-sony-*
3228 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3230 *** Changes in GDB 6.1.1:
3232 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3234 The TUI (Text-mode User Interface) is now built as part of a default
3235 GDB configuration. It is enabled by either selecting the TUI with the
3236 command line option "-i=tui" or by running the separate "gdbtui"
3237 program. For more information on the TUI, see the manual "Debugging
3240 * Pending breakpoint support (also included in GDB 6.1)
3242 Support has been added to allow you to specify breakpoints in shared
3243 libraries that have not yet been loaded. If a breakpoint location
3244 cannot be found, and the "breakpoint pending" option is set to auto,
3245 GDB queries you if you wish to make the breakpoint pending on a future
3246 shared-library load. If and when GDB resolves the breakpoint symbol,
3247 the pending breakpoint is removed as one or more regular breakpoints
3250 Pending breakpoints are very useful for GCJ Java debugging.
3252 * Fixed ISO-C build problems
3254 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3255 non ISO-C code that stopped them being built using a more strict ISO-C
3256 compiler (e.g., IBM's C compiler).
3258 * Fixed build problem on IRIX 5
3260 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3261 wasn't able to compile compile on an IRIX 5 system.
3263 * Added execute permission to gdb/gdbserver/configure
3265 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3266 permission. This bug would cause configure to fail on a number of
3267 systems (Solaris, IRIX). Ref: server/519.
3269 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3271 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3272 has been updated to use constant array sizes.
3274 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3276 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3277 its generated DWARF Call Frame Info. This encoding was causing GDB to
3278 panic, that panic has been fixed. Ref: gdb/1628.
3280 * Fixed a problem when examining parameters in shared library code.
3282 When examining parameters in optimized shared library code generated
3283 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3284 not available''. GDB now correctly displays the variable's value.
3286 *** Changes in GDB 6.1:
3288 * Removed --with-mmalloc
3290 Support for the mmalloc memory manager has been removed, as it
3291 conflicted with the internal gdb byte cache.
3293 * Changes in AMD64 configurations
3295 The AMD64 target now includes the %cs and %ss registers. As a result
3296 the AMD64 remote protocol has changed; this affects the floating-point
3297 and SSE registers. If you rely on those registers for your debugging,
3298 you should upgrade gdbserver on the remote side.
3300 * Revised SPARC target
3302 The SPARC target has been completely revised, incorporating the
3303 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3304 support for LynxOS and SunOS 4 has been dropped. Calling functions
3305 from within GDB on operating systems with a non-executable stack
3306 (Solaris, OpenBSD) now works.
3310 GDB has a new C++ demangler which does a better job on the mangled
3311 names generated by current versions of g++. It also runs faster, so
3312 with this and other changes gdb should now start faster on large C++
3315 * DWARF 2 Location Expressions
3317 GDB support for location expressions has been extended to support function
3318 arguments and frame bases. Older versions of GDB could crash when they
3321 * C++ nested types and namespaces
3323 GDB's support for nested types and namespaces in C++ has been
3324 improved, especially if you use the DWARF 2 debugging format. (This
3325 is the default for recent versions of GCC on most platforms.)
3326 Specifically, if you have a class "Inner" defined within a class or
3327 namespace "Outer", then GDB realizes that the class's name is
3328 "Outer::Inner", not simply "Inner". This should greatly reduce the
3329 frequency of complaints about not finding RTTI symbols. In addition,
3330 if you are stopped at inside of a function defined within a namespace,
3331 GDB modifies its name lookup accordingly.
3333 * New native configurations
3335 NetBSD/amd64 x86_64-*-netbsd*
3336 OpenBSD/amd64 x86_64-*-openbsd*
3337 OpenBSD/alpha alpha*-*-openbsd*
3338 OpenBSD/sparc sparc-*-openbsd*
3339 OpenBSD/sparc64 sparc64-*-openbsd*
3341 * New debugging protocols
3343 M32R with SDI protocol m32r-*-elf*
3345 * "set prompt-escape-char" command deleted.
3347 The command "set prompt-escape-char" has been deleted. This command,
3348 and its very obscure effet on GDB's prompt, was never documented,
3349 tested, nor mentioned in the NEWS file.
3351 * OBSOLETE configurations and files
3353 Configurations that have been declared obsolete in this release have
3354 been commented out. Unless there is activity to revive these
3355 configurations, the next release of GDB will have their sources
3356 permanently REMOVED.
3358 Sun 3, running SunOS 3 m68*-*-sunos3*
3359 Sun 3, running SunOS 4 m68*-*-sunos4*
3360 Sun 2, running SunOS 3 m68000-*-sunos3*
3361 Sun 2, running SunOS 4 m68000-*-sunos4*
3362 Motorola 680x0 running LynxOS m68*-*-lynxos*
3363 AT&T 3b1/Unix pc m68*-att-*
3364 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3365 decstation mips-dec-* mips-little-*
3366 riscos mips-*-riscos* mips-*-sysv*
3367 sonymips mips-sony-*
3368 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3370 * REMOVED configurations and files
3372 SGI Irix-4.x mips-sgi-irix4 or iris4
3373 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3374 Z8000 simulator z8k-zilog-none or z8ksim
3375 Matsushita MN10200 w/simulator mn10200-*-*
3376 H8/500 simulator h8500-hitachi-hms or h8500hms
3377 HP/PA running BSD hppa*-*-bsd*
3378 HP/PA running OSF/1 hppa*-*-osf*
3379 HP/PA Pro target hppa*-*-pro*
3380 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3381 386BSD i[3456]86-*-bsd*
3382 Sequent family i[3456]86-sequent-sysv4*
3383 i[3456]86-sequent-sysv*
3384 i[3456]86-sequent-bsd*
3385 SPARC running LynxOS sparc-*-lynxos*
3386 SPARC running SunOS 4 sparc-*-sunos4*
3387 Tsqware Sparclet sparclet-*-*
3388 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3390 *** Changes in GDB 6.0:
3394 Support for debugging the Objective-C programming language has been
3395 integrated into GDB.
3397 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3399 DWARF 2's Call Frame Information makes available compiler generated
3400 information that more exactly describes the program's run-time stack.
3401 By using this information, GDB is able to provide more robust stack
3404 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3405 have been updated to use a new backtrace mechanism which includes
3406 DWARF 2 CFI support.
3410 GDB's remote protocol has been extended to include support for hosted
3411 file I/O (where the remote target uses GDB's file system). See GDB's
3412 remote protocol documentation for details.
3414 * All targets using the new architecture framework.
3416 All of GDB's targets have been updated to use the new internal
3417 architecture framework. The way is now open for future GDB releases
3418 to include cross-architecture native debugging support (i386 on amd64,
3421 * GNU/Linux's Thread Local Storage (TLS)
3423 GDB now includes support for for the GNU/Linux implementation of
3424 per-thread variables.
3426 * GNU/Linux's Native POSIX Thread Library (NPTL)
3428 GDB's thread code has been updated to work with either the new
3429 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3431 * Separate debug info.
3433 GDB, in conjunction with BINUTILS, now supports a mechanism for
3434 automatically loading debug information from a separate file. Instead
3435 of shipping full debug and non-debug versions of system libraries,
3436 system integrators can now instead ship just the stripped libraries
3437 and optional debug files.
3439 * DWARF 2 Location Expressions
3441 DWARF 2 Location Expressions allow the compiler to more completely
3442 describe the location of variables (even in optimized code) to the
3445 GDB now includes preliminary support for location expressions (support
3446 for DW_OP_piece is still missing).
3450 A number of long standing bugs that caused GDB to die while starting a
3451 Java application have been fixed. GDB's Java support is now
3452 considered "useable".
3454 * GNU/Linux support for fork, vfork, and exec.
3456 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3457 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3460 * GDB supports logging output to a file
3462 There are two new commands, "set logging" and "show logging", which can be
3463 used to capture GDB's output to a file.
3465 * The meaning of "detach" has changed for gdbserver
3467 The "detach" command will now resume the application, as documented. To
3468 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3471 * d10v, m68hc11 `regs' command deprecated
3473 The `info registers' command has been updated so that it displays the
3474 registers using a format identical to the old `regs' command.
3478 A new command, "maint set profile on/off", has been added. This command can
3479 be used to enable or disable profiling while running GDB, to profile a
3480 session or a set of commands. In addition there is a new configure switch,
3481 "--enable-profiling", which will cause GDB to be compiled with profiling
3482 data, for more informative profiling results.
3484 * Default MI syntax changed to "mi2".
3486 The default MI (machine interface) syntax, enabled by the command line
3487 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3488 "mi1", can be enabled by specifying the option "-i=mi1".
3490 Support for the original "mi0" syntax (included in GDB 5.0) has been
3493 Fix for gdb/192: removed extraneous space when displaying frame level.
3494 Fix for gdb/672: update changelist is now output in mi list format.
3495 Fix for gdb/702: a -var-assign that updates the value now shows up
3496 in a subsequent -var-update.
3498 * New native configurations.
3500 FreeBSD/amd64 x86_64-*-freebsd*
3502 * Multi-arched targets.
3504 HP/PA HPUX11 hppa*-*-hpux*
3505 Renesas M32R/D w/simulator m32r-*-elf*
3507 * OBSOLETE configurations and files
3509 Configurations that have been declared obsolete in this release have
3510 been commented out. Unless there is activity to revive these
3511 configurations, the next release of GDB will have their sources
3512 permanently REMOVED.
3514 Z8000 simulator z8k-zilog-none or z8ksim
3515 Matsushita MN10200 w/simulator mn10200-*-*
3516 H8/500 simulator h8500-hitachi-hms or h8500hms
3517 HP/PA running BSD hppa*-*-bsd*
3518 HP/PA running OSF/1 hppa*-*-osf*
3519 HP/PA Pro target hppa*-*-pro*
3520 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3521 Sequent family i[3456]86-sequent-sysv4*
3522 i[3456]86-sequent-sysv*
3523 i[3456]86-sequent-bsd*
3524 Tsqware Sparclet sparclet-*-*
3525 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3527 * REMOVED configurations and files
3530 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3531 IBM AIX PS/2 i[3456]86-*-aix
3532 i386 running Mach 3.0 i[3456]86-*-mach3*
3533 i386 running Mach i[3456]86-*-mach*
3534 i386 running OSF/1 i[3456]86-*osf1mk*
3535 HP/Apollo 68k Family m68*-apollo*-sysv*,
3537 m68*-hp-bsd*, m68*-hp-hpux*
3538 Argonaut Risc Chip (ARC) arc-*-*
3539 Mitsubishi D30V d30v-*-*
3540 Fujitsu FR30 fr30-*-elf*
3541 OS/9000 i[34]86-*-os9k
3542 I960 with MON960 i960-*-coff
3544 * MIPS $fp behavior changed
3546 The convenience variable $fp, for the MIPS, now consistently returns
3547 the address of the current frame's base. Previously, depending on the
3548 context, $fp could refer to either $sp or the current frame's base
3549 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3550 The GNU Source-Level Debugger''.
3552 *** Changes in GDB 5.3:
3554 * GNU/Linux shared library multi-threaded performance improved.
3556 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3557 `/proc', in preference to `ptrace' for memory reads. This may result
3558 in an improvement in the start-up time of multi-threaded, shared
3559 library applications when run under GDB. One GDB user writes: ``loads
3560 shared libs like mad''.
3562 * ``gdbserver'' now supports multi-threaded applications on some targets
3564 Support for debugging multi-threaded applications which use
3565 the GNU/Linux LinuxThreads package has been added for
3566 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3567 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3569 * GDB now supports C/C++ preprocessor macros.
3571 GDB now expands preprocessor macro invocations in C/C++ expressions,
3572 and provides various commands for showing macro definitions and how
3575 The new command `macro expand EXPRESSION' expands any macro
3576 invocations in expression, and shows the result.
3578 The new command `show macro MACRO-NAME' shows the definition of the
3579 macro named MACRO-NAME, and where it was defined.
3581 Most compilers don't include information about macros in the debugging
3582 information by default. In GCC 3.1, for example, you need to compile
3583 your program with the options `-gdwarf-2 -g3'. If the macro
3584 information is present in the executable, GDB will read it.
3586 * Multi-arched targets.
3588 DEC Alpha (partial) alpha*-*-*
3589 DEC VAX (partial) vax-*-*
3591 National Semiconductor NS32000 (partial) ns32k-*-*
3592 Motorola 68000 (partial) m68k-*-*
3593 Motorola MCORE mcore-*-*
3597 Fujitsu FRV architecture added by Red Hat frv*-*-*
3600 * New native configurations
3602 Alpha NetBSD alpha*-*-netbsd*
3603 SH NetBSD sh*-*-netbsdelf*
3604 MIPS NetBSD mips*-*-netbsd*
3605 UltraSPARC NetBSD sparc64-*-netbsd*
3607 * OBSOLETE configurations and files
3609 Configurations that have been declared obsolete in this release have
3610 been commented out. Unless there is activity to revive these
3611 configurations, the next release of GDB will have their sources
3612 permanently REMOVED.
3614 Mitsubishi D30V d30v-*-*
3615 OS/9000 i[34]86-*-os9k
3616 IBM AIX PS/2 i[3456]86-*-aix
3617 Fujitsu FR30 fr30-*-elf*
3618 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3619 Argonaut Risc Chip (ARC) arc-*-*
3620 i386 running Mach 3.0 i[3456]86-*-mach3*
3621 i386 running Mach i[3456]86-*-mach*
3622 i386 running OSF/1 i[3456]86-*osf1mk*
3623 HP/Apollo 68k Family m68*-apollo*-sysv*,
3625 m68*-hp-bsd*, m68*-hp-hpux*
3626 I960 with MON960 i960-*-coff
3628 * OBSOLETE languages
3630 CHILL, a Pascal like language used by telecommunications companies.
3632 * REMOVED configurations and files
3634 AMD 29k family via UDI a29k-amd-udi, udi29k
3635 A29K VxWorks a29k-*-vxworks
3636 AMD 29000 embedded, using EBMON a29k-none-none
3637 AMD 29000 embedded with COFF a29k-none-coff
3638 AMD 29000 embedded with a.out a29k-none-aout
3640 testsuite/gdb.hp/gdb.threads-hp/ directory
3642 * New command "set max-user-call-depth <nnn>"
3644 This command allows the user to limit the call depth of user-defined
3645 commands. The default is 1024.
3647 * Changes in FreeBSD/i386 native debugging.
3649 Support for the "generate-core-file" has been added.
3651 * New commands "dump", "append", and "restore".
3653 These commands allow data to be copied from target memory
3654 to a bfd-format or binary file (dump and append), and back
3655 from a file into memory (restore).
3657 * Improved "next/step" support on multi-processor Alpha Tru64.
3659 The previous single-step mechanism could cause unpredictable problems,
3660 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3661 of a software single-step mechanism prevents this.
3663 *** Changes in GDB 5.2.1:
3671 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3672 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3673 Fix, by Joel Brobecker imported from mainline.
3675 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3676 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3677 Fix, by Fred Fish, imported from mainline.
3679 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3680 Surprisingly enough, it works now.
3681 By Michal Ludvig, imported from mainline.
3683 i386 hardware watchpoint support:
3684 avoid misses on second run for some targets.
3685 By Pierre Muller, imported from mainline.
3687 *** Changes in GDB 5.2:
3689 * New command "set trust-readonly-sections on[off]".
3691 This command is a hint that tells gdb that read-only sections
3692 really are read-only (ie. that their contents will not change).
3693 In this mode, gdb will go to the object file rather than the
3694 target to read memory from read-only sections (such as ".text").
3695 This can be a significant performance improvement on some
3696 (notably embedded) targets.
3698 * New command "generate-core-file" (or "gcore").
3700 This new gdb command allows the user to drop a core file of the child
3701 process state at any time. So far it's been implemented only for
3702 GNU/Linux and Solaris, but should be relatively easily ported to other
3703 hosts. Argument is core file name (defaults to core.<pid>).
3705 * New command line option
3707 GDB now accepts --pid or -p followed by a process id.
3709 * Change in command line behavior -- corefiles vs. process ids.
3711 There is a subtle behavior in the way in which GDB handles
3712 command line arguments. The first non-flag argument is always
3713 a program to debug, but the second non-flag argument may either
3714 be a corefile or a process id. Previously, GDB would attempt to
3715 open the second argument as a corefile, and if that failed, would
3716 issue a superfluous error message and then attempt to attach it as
3717 a process. Now, if the second argument begins with a non-digit,
3718 it will be treated as a corefile. If it begins with a digit,
3719 GDB will attempt to attach it as a process, and if no such process
3720 is found, will then attempt to open it as a corefile.
3722 * Changes in ARM configurations.
3724 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3725 configuration is fully multi-arch.
3727 * New native configurations
3729 ARM NetBSD arm*-*-netbsd*
3730 x86 OpenBSD i[3456]86-*-openbsd*
3731 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3732 Sparc64 running FreeBSD sparc64-*-freebsd*
3736 Sanyo XStormy16 xstormy16-elf
3738 * OBSOLETE configurations and files
3740 Configurations that have been declared obsolete in this release have
3741 been commented out. Unless there is activity to revive these
3742 configurations, the next release of GDB will have their sources
3743 permanently REMOVED.
3745 AMD 29k family via UDI a29k-amd-udi, udi29k
3746 A29K VxWorks a29k-*-vxworks
3747 AMD 29000 embedded, using EBMON a29k-none-none
3748 AMD 29000 embedded with COFF a29k-none-coff
3749 AMD 29000 embedded with a.out a29k-none-aout
3751 testsuite/gdb.hp/gdb.threads-hp/ directory
3753 * REMOVED configurations and files
3755 TI TMS320C80 tic80-*-*
3757 PowerPC Solaris powerpcle-*-solaris*
3758 PowerPC Windows NT powerpcle-*-cygwin32
3759 PowerPC Netware powerpc-*-netware*
3760 Harris/CXUX m88k m88*-harris-cxux*
3761 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3762 ns32k-utek-sysv* ns32k-utek-*
3763 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3764 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3765 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3766 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3767 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3769 * Changes to command line processing
3771 The new `--args' feature can be used to specify command-line arguments
3772 for the inferior from gdb's command line.
3774 * Changes to key bindings
3776 There is a new `operate-and-get-next' function bound to `C-o'.
3778 *** Changes in GDB 5.1.1
3780 Fix compile problem on DJGPP.
3782 Fix a problem with floating-point registers on the i386 being
3785 Fix to stop GDB crashing on .debug_str debug info.
3787 Numerous documentation fixes.
3789 Numerous testsuite fixes.
3791 *** Changes in GDB 5.1:
3793 * New native configurations
3795 Alpha FreeBSD alpha*-*-freebsd*
3796 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3797 MIPS GNU/Linux mips*-*-linux*
3798 MIPS SGI Irix 6.x mips*-sgi-irix6*
3799 ia64 AIX ia64-*-aix*
3800 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3804 Motorola 68HC11 and 68HC12 m68hc11-elf
3806 UltraSparc running GNU/Linux sparc64-*-linux*
3808 * OBSOLETE configurations and files
3810 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3811 Harris/CXUX m88k m88*-harris-cxux*
3812 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3813 ns32k-utek-sysv* ns32k-utek-*
3814 TI TMS320C80 tic80-*-*
3816 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3817 PowerPC Solaris powerpcle-*-solaris*
3818 PowerPC Windows NT powerpcle-*-cygwin32
3819 PowerPC Netware powerpc-*-netware*
3820 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3821 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3822 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3823 Apple Macintosh (MPW) host N/A
3825 stuff.c (Program to stuff files into a specially prepared space in kdb)
3826 kdb-start.c (Main loop for the standalone kernel debugger)
3828 Configurations that have been declared obsolete in this release have
3829 been commented out. Unless there is activity to revive these
3830 configurations, the next release of GDB will have their sources
3831 permanently REMOVED.
3833 * REMOVED configurations and files
3835 Altos 3068 m68*-altos-*
3836 Convex c1-*-*, c2-*-*
3838 ARM RISCix arm-*-* (as host)
3842 * GDB has been converted to ISO C.
3844 GDB's source code has been converted to ISO C. In particular, the
3845 sources are fully protoized, and rely on standard headers being
3850 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3852 * The MI enabled by default.
3854 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3855 revised and enabled by default. Packages which use GDB as a debugging
3856 engine behind a UI or another front end are encouraged to switch to
3857 using the GDB/MI interface, instead of the old annotations interface
3858 which is now deprecated.
3860 * Support for debugging Pascal programs.
3862 GDB now includes support for debugging Pascal programs. The following
3863 main features are supported:
3865 - Pascal-specific data types such as sets;
3867 - automatic recognition of Pascal sources based on file-name
3870 - Pascal-style display of data types, variables, and functions;
3872 - a Pascal expression parser.
3874 However, some important features are not yet supported.
3876 - Pascal string operations are not supported at all;
3878 - there are some problems with boolean types;
3880 - Pascal type hexadecimal constants are not supported
3881 because they conflict with the internal variables format;
3883 - support for Pascal objects and classes is not full yet;
3885 - unlike Pascal, GDB is case-sensitive for symbol names.
3887 * Changes in completion.
3889 Commands such as `shell', `run' and `set args', which pass arguments
3890 to inferior programs, now complete on file names, similar to what
3891 users expect at the shell prompt.
3893 Commands which accept locations, such as `disassemble', `print',
3894 `breakpoint', `until', etc. now complete on filenames as well as
3895 program symbols. Thus, if you type "break foob TAB", and the source
3896 files linked into the programs include `foobar.c', that file name will
3897 be one of the candidates for completion. However, file names are not
3898 considered for completion after you typed a colon that delimits a file
3899 name from a name of a function in that file, as in "break foo.c:bar".
3901 `set demangle-style' completes on available demangling styles.
3903 * New platform-independent commands:
3905 It is now possible to define a post-hook for a command as well as a
3906 hook that runs before the command. For more details, see the
3907 documentation of `hookpost' in the GDB manual.
3909 * Changes in GNU/Linux native debugging.
3911 Support for debugging multi-threaded programs has been completely
3912 revised for all platforms except m68k and sparc. You can now debug as
3913 many threads as your system allows you to have.
3915 Attach/detach is supported for multi-threaded programs.
3917 Support for SSE registers was added for x86. This doesn't work for
3918 multi-threaded programs though.
3920 * Changes in MIPS configurations.
3922 Multi-arch support is enabled for all MIPS configurations.
3924 GDB can now be built as native debugger on SGI Irix 6.x systems for
3925 debugging n32 executables. (Debugging 64-bit executables is not yet
3928 * Unified support for hardware watchpoints in all x86 configurations.
3930 Most (if not all) native x86 configurations support hardware-assisted
3931 breakpoints and watchpoints in a unified manner. This support
3932 implements debug register sharing between watchpoints, which allows to
3933 put a virtually infinite number of watchpoints on the same address,
3934 and also supports watching regions up to 16 bytes with several debug
3937 The new maintenance command `maintenance show-debug-regs' toggles
3938 debugging print-outs in functions that insert, remove, and test
3939 watchpoints and hardware breakpoints.
3941 * Changes in the DJGPP native configuration.
3943 New command ``info dos sysinfo'' displays assorted information about
3944 the CPU, OS, memory, and DPMI server.
3946 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3947 display information about segment descriptors stored in GDT, LDT, and
3950 New commands ``info dos pde'' and ``info dos pte'' display entries
3951 from Page Directory and Page Tables (for now works with CWSDPMI only).
3952 New command ``info dos address-pte'' displays the Page Table entry for
3953 a given linear address.
3955 GDB can now pass command lines longer than 126 characters to the
3956 program being debugged (requires an update to the libdbg.a library
3957 which is part of the DJGPP development kit).
3959 DWARF2 debug info is now supported.
3961 It is now possible to `step' and `next' through calls to `longjmp'.
3963 * Changes in documentation.
3965 All GDB documentation was converted to GFDL, the GNU Free
3966 Documentation License.
3968 Tracepoints-related commands are now fully documented in the GDB
3971 TUI, the Text-mode User Interface, is now documented in the manual.
3973 Tracepoints-related commands are now fully documented in the GDB
3976 The "GDB Internals" manual now has an index. It also includes
3977 documentation of `ui_out' functions, GDB coding standards, x86
3978 hardware watchpoints, and memory region attributes.
3980 * GDB's version number moved to ``version.in''
3982 The Makefile variable VERSION has been replaced by the file
3983 ``version.in''. People creating GDB distributions should update the
3984 contents of this file.
3988 GUD support is now a standard part of the EMACS distribution.
3990 *** Changes in GDB 5.0:
3992 * Improved support for debugging FP programs on x86 targets
3994 Unified and much-improved support for debugging floating-point
3995 programs on all x86 targets. In particular, ``info float'' now
3996 displays the FP registers in the same format on all x86 targets, with
3997 greater level of detail.
3999 * Improvements and bugfixes in hardware-assisted watchpoints
4001 It is now possible to watch array elements, struct members, and
4002 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4003 on x86 targets no longer erroneously trigger when the address is
4006 * Improvements in the native DJGPP version of GDB
4008 The distribution now includes all the scripts and auxiliary files
4009 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4010 machines ``out of the box''.
4012 The DJGPP version can now debug programs that use signals. It is
4013 possible to catch signals that happened in the debuggee, deliver
4014 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4015 would kill the program being debugged.) Programs that hook hardware
4016 interrupts (keyboard, timer, etc.) can also be debugged.
4018 It is now possible to debug DJGPP programs that redirect their
4019 standard handles or switch them to raw (as opposed to cooked) mode, or
4020 even close them. The command ``run < foo > bar'' works as expected,
4021 and ``info terminal'' reports useful information about the debuggee's
4022 terminal, including raw/cooked mode, redirection, etc.
4024 The DJGPP version now uses termios functions for console I/O, which
4025 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4028 DOS-style file names with drive letters are now fully supported by
4031 It is now possible to debug DJGPP programs that switch their working
4032 directory. It is also possible to rerun the debuggee any number of
4033 times without restarting GDB; thus, you can use the same setup,
4034 breakpoints, etc. for many debugging sessions.
4036 * New native configurations
4038 ARM GNU/Linux arm*-*-linux*
4039 PowerPC GNU/Linux powerpc-*-linux*
4043 Motorola MCore mcore-*-*
4044 x86 VxWorks i[3456]86-*-vxworks*
4045 PowerPC VxWorks powerpc-*-vxworks*
4046 TI TMS320C80 tic80-*-*
4048 * OBSOLETE configurations
4050 Altos 3068 m68*-altos-*
4051 Convex c1-*-*, c2-*-*
4053 ARM RISCix arm-*-* (as host)
4056 Configurations that have been declared obsolete will be commented out,
4057 but the code will be left in place. If there is no activity to revive
4058 these configurations before the next release of GDB, the sources will
4059 be permanently REMOVED.
4061 * Gould support removed
4063 Support for the Gould PowerNode and NP1 has been removed.
4065 * New features for SVR4
4067 On SVR4 native platforms (such as Solaris), if you attach to a process
4068 without first loading a symbol file, GDB will now attempt to locate and
4069 load symbols from the running process's executable file.
4071 * Many C++ enhancements
4073 C++ support has been greatly improved. Overload resolution now works properly
4074 in almost all cases. RTTI support is on the way.
4076 * Remote targets can connect to a sub-program
4078 A popen(3) style serial-device has been added. This device starts a
4079 sub-process (such as a stand-alone simulator) and then communicates
4080 with that. The sub-program to run is specified using the syntax
4081 ``|<program> <args>'' vis:
4083 (gdb) set remotedebug 1
4084 (gdb) target extended-remote |mn10300-elf-sim program-args
4086 * MIPS 64 remote protocol
4088 A long standing bug in the mips64 remote protocol where by GDB
4089 expected certain 32 bit registers (ex SR) to be transfered as 32
4090 instead of 64 bits has been fixed.
4092 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4093 added to provide backward compatibility with older versions of GDB.
4095 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4097 The command ``set remotebinarydownload'' command has been replaced by
4098 ``set remote X-packet''. Other commands in ``set remote'' family
4099 include ``set remote P-packet''.
4101 * Breakpoint commands accept ranges.
4103 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4104 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4105 ``tracepoint passcount'' also accepts a range of tracepoints.
4107 * ``apropos'' command added.
4109 The ``apropos'' command searches through command names and
4110 documentation strings, printing out matches, making it much easier to
4111 try to find a command that does what you are looking for.
4115 A new machine oriented interface (MI) has been added to GDB. This
4116 interface is designed for debug environments running GDB as a separate
4117 process. This is part of the long term libGDB project. See the
4118 "GDB/MI" chapter of the GDB manual for further information. It can be
4119 enabled by configuring with:
4121 .../configure --enable-gdbmi
4123 *** Changes in GDB-4.18:
4125 * New native configurations
4127 HP-UX 10.20 hppa*-*-hpux10.20
4128 HP-UX 11.x hppa*-*-hpux11.0*
4129 M68K GNU/Linux m68*-*-linux*
4133 Fujitsu FR30 fr30-*-elf*
4134 Intel StrongARM strongarm-*-*
4135 Mitsubishi D30V d30v-*-*
4137 * OBSOLETE configurations
4139 Gould PowerNode, NP1 np1-*-*, pn-*-*
4141 Configurations that have been declared obsolete will be commented out,
4142 but the code will be left in place. If there is no activity to revive
4143 these configurations before the next release of GDB, the sources will
4144 be permanently REMOVED.
4148 As a compatibility experiment, GDB's source files buildsym.h and
4149 buildsym.c have been converted to pure standard C, no longer
4150 containing any K&R compatibility code. We believe that all systems in
4151 use today either come with a standard C compiler, or have a GCC port
4152 available. If this is not true, please report the affected
4153 configuration to bug-gdb@gnu.org immediately. See the README file for
4154 information about getting a standard C compiler if you don't have one
4159 GDB now uses readline 2.2.
4161 * set extension-language
4163 You can now control the mapping between filename extensions and source
4164 languages by using the `set extension-language' command. For instance,
4165 you can ask GDB to treat .c files as C++ by saying
4166 set extension-language .c c++
4167 The command `info extensions' lists all of the recognized extensions
4168 and their associated languages.
4170 * Setting processor type for PowerPC and RS/6000
4172 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4173 you can use the `set processor' command to specify what variant of the
4174 PowerPC family you are debugging. The command
4178 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4179 following PowerPC and RS6000 variants:
4181 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4182 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4184 403GC IBM PowerPC 403GC
4185 505 Motorola PowerPC 505
4186 860 Motorola PowerPC 860 or 850
4187 601 Motorola PowerPC 601
4188 602 Motorola PowerPC 602
4189 603 Motorola/IBM PowerPC 603 or 603e
4190 604 Motorola PowerPC 604 or 604e
4191 750 Motorola/IBM PowerPC 750 or 750
4193 At the moment, this command just tells GDB what to name the
4194 special-purpose processor registers. Since almost all the affected
4195 registers are inaccessible to user-level programs, this command is
4196 only useful for remote debugging in its present form.
4200 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4201 more extensive support for HP-UX. Added features include shared
4202 library support, kernel threads and hardware watchpoints for 11.00,
4203 support for HP's ANSI C and C++ compilers, and a compatibility mode
4204 for xdb and dbx commands.
4208 HP's donation includes the new concept of catchpoints, which is a
4209 generalization of the old catch command. On HP-UX, it is now possible
4210 to catch exec, fork, and vfork, as well as library loading.
4212 This means that the existing catch command has changed; its first
4213 argument now specifies the type of catch to be set up. See the
4214 output of "help catch" for a list of catchpoint types.
4216 * Debugging across forks
4218 On HP-UX, you can choose which process to debug when a fork() happens
4223 HP has donated a curses-based terminal user interface (TUI). To get
4224 it, build with --enable-tui. Although this can be enabled for any
4225 configuration, at present it only works for native HP debugging.
4227 * GDB remote protocol additions
4229 A new protocol packet 'X' that writes binary data is now available.
4230 Default behavior is to try 'X', then drop back to 'M' if the stub
4231 fails to respond. The settable variable `remotebinarydownload'
4232 allows explicit control over the use of 'X'.
4234 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4235 full 64-bit address. The command
4237 set remoteaddresssize 32
4239 can be used to revert to the old behaviour. For existing remote stubs
4240 the change should not be noticed, as the additional address information
4243 In order to assist in debugging stubs, you may use the maintenance
4244 command `packet' to send any text string to the stub. For instance,
4246 maint packet heythere
4248 sends the packet "$heythere#<checksum>". Note that it is very easy to
4249 disrupt a debugging session by sending the wrong packet at the wrong
4252 The compare-sections command allows you to compare section data on the
4253 target to what is in the executable file without uploading or
4254 downloading, by comparing CRC checksums.
4256 * Tracing can collect general expressions
4258 You may now collect general expressions at tracepoints. This requires
4259 further additions to the target-side stub; see tracepoint.c and
4260 doc/agentexpr.texi for further details.
4262 * mask-address variable for Mips
4264 For Mips targets, you may control the zeroing of the upper 32 bits of
4265 a 64-bit address by entering `set mask-address on'. This is mainly
4266 of interest to users of embedded R4xxx and R5xxx processors.
4268 * Higher serial baud rates
4270 GDB's serial code now allows you to specify baud rates 57600, 115200,
4271 230400, and 460800 baud. (Note that your host system may not be able
4272 to achieve all of these rates.)
4276 The i960 configuration now includes an initial implementation of a
4277 builtin simulator, contributed by Jim Wilson.
4280 *** Changes in GDB-4.17:
4282 * New native configurations
4284 Alpha GNU/Linux alpha*-*-linux*
4285 Unixware 2.x i[3456]86-unixware2*
4286 Irix 6.x mips*-sgi-irix6*
4287 PowerPC GNU/Linux powerpc-*-linux*
4288 PowerPC Solaris powerpcle-*-solaris*
4289 Sparc GNU/Linux sparc-*-linux*
4290 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4294 Argonaut Risc Chip (ARC) arc-*-*
4295 Hitachi H8/300S h8300*-*-*
4296 Matsushita MN10200 w/simulator mn10200-*-*
4297 Matsushita MN10300 w/simulator mn10300-*-*
4298 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4299 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4300 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4301 Mitsubishi D10V w/simulator d10v-*-*
4302 Mitsubishi M32R/D w/simulator m32r-*-elf*
4303 Tsqware Sparclet sparclet-*-*
4304 NEC V850 w/simulator v850-*-*
4306 * New debugging protocols
4308 ARM with RDI protocol arm*-*-*
4309 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4310 DDB and LSI variants of PMON protocol mips*-*-*
4311 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4312 PowerPC with SDS protocol powerpc{,le}-*-eabi
4313 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4317 All configurations can now understand and use the DWARF 2 debugging
4318 format. The choice is automatic, if the symbol file contains DWARF 2
4323 GDB now includes basic Java language support. This support is
4324 only useful with Java compilers that produce native machine code.
4326 * solib-absolute-prefix and solib-search-path
4328 For SunOS and SVR4 shared libraries, you may now set the prefix for
4329 loading absolute shared library symbol files, and the search path for
4330 locating non-absolute shared library symbol files.
4332 * Live range splitting
4334 GDB can now effectively debug code for which GCC has performed live
4335 range splitting as part of its optimization. See gdb/doc/LRS for
4336 more details on the expected format of the stabs information.
4340 GDB's support for the GNU Hurd, including thread debugging, has been
4341 updated to work with current versions of the Hurd.
4345 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4346 instruction set. ARM GDB automatically detects when Thumb
4347 instructions are in use, and adjusts disassembly and backtracing
4352 GDB's MIPS target configurations now handle the MIP16 16-bit
4357 GDB now includes support for overlays; if an executable has been
4358 linked such that multiple sections are based at the same address, GDB
4359 will decide which section to use for symbolic info. You can choose to
4360 control the decision manually, using overlay commands, or implement
4361 additional target-side support and use "overlay load-target" to bring
4362 in the overlay mapping. Do "help overlay" for more detail.
4366 The command "info symbol <address>" displays information about
4367 the symbol at the specified address.
4371 The standard remote protocol now includes an extension that allows
4372 asynchronous collection and display of trace data. This requires
4373 extensive support in the target-side debugging stub. Tracing mode
4374 includes a new interaction mode in GDB and new commands: see the
4375 file tracepoint.c for more details.
4379 Configurations for embedded MIPS now include a simulator contributed
4380 by Cygnus Solutions. The simulator supports the instruction sets
4381 of most MIPS variants.
4385 Sparc configurations may now include the ERC32 simulator contributed
4386 by the European Space Agency. The simulator is not built into
4387 Sparc targets by default; configure with --enable-sim to include it.
4391 For target configurations that may include multiple variants of a
4392 basic architecture (such as MIPS and SH), you may now set the
4393 architecture explicitly. "set arch" sets, "info arch" lists
4394 the possible architectures.
4396 *** Changes in GDB-4.16:
4398 * New native configurations
4400 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4401 M68K NetBSD m68k-*-netbsd*
4402 PowerPC AIX 4.x powerpc-*-aix*
4403 PowerPC MacOS powerpc-*-macos*
4404 PowerPC Windows NT powerpcle-*-cygwin32
4405 RS/6000 AIX 4.x rs6000-*-aix4*
4409 ARM with RDP protocol arm-*-*
4410 I960 with MON960 i960-*-coff
4411 MIPS VxWorks mips*-*-vxworks*
4412 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4413 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4415 Matra Sparclet sparclet-*-*
4419 The powerpc-eabi configuration now includes the PSIM simulator,
4420 contributed by Andrew Cagney, with assistance from Mike Meissner.
4421 PSIM is a very elaborate model of the PowerPC, including not only
4422 basic instruction set execution, but also details of execution unit
4423 performance and I/O hardware. See sim/ppc/README for more details.
4427 GDB now works with Solaris 2.5.
4429 * Windows 95/NT native
4431 GDB will now work as a native debugger on Windows 95 and Windows NT.
4432 To build it from source, you must use the "gnu-win32" environment,
4433 which uses a DLL to emulate enough of Unix to run the GNU tools.
4434 Further information, binaries, and sources are available at
4435 ftp.cygnus.com, under pub/gnu-win32.
4437 * dont-repeat command
4439 If a user-defined command includes the command `dont-repeat', then the
4440 command will not be repeated if the user just types return. This is
4441 useful if the command is time-consuming to run, so that accidental
4442 extra keystrokes don't run the same command many times.
4444 * Send break instead of ^C
4446 The standard remote protocol now includes an option to send a break
4447 rather than a ^C to the target in order to interrupt it. By default,
4448 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4450 * Remote protocol timeout
4452 The standard remote protocol includes a new variable `remotetimeout'
4453 that allows you to set the number of seconds before GDB gives up trying
4454 to read from the target. The default value is 2.
4456 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4458 By default GDB will automatically keep track of objects as they are
4459 loaded and unloaded by the dynamic linker. By using the command `set
4460 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4461 when shared library events occur, thus allowing you to set breakpoints
4462 in shared libraries which are explicitly loaded by the inferior.
4464 Note this feature does not work on hpux8. On hpux9 you must link
4465 /usr/lib/end.o into your program. This feature should work
4466 automatically on hpux10.
4468 * Irix 5.x hardware watchpoint support
4470 Irix 5 configurations now support the use of hardware watchpoints.
4472 * Mips protocol "SYN garbage limit"
4474 When debugging a Mips target using the `target mips' protocol, you
4475 may set the number of characters that GDB will ignore by setting
4476 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4477 every character. The default value is 1050.
4479 * Recording and replaying remote debug sessions
4481 If you set `remotelogfile' to the name of a file, gdb will write to it
4482 a recording of a remote debug session. This recording may then be
4483 replayed back to gdb using "gdbreplay". See gdbserver/README for
4484 details. This is useful when you have a problem with GDB while doing
4485 remote debugging; you can make a recording of the session and send it
4486 to someone else, who can then recreate the problem.
4488 * Speedups for remote debugging
4490 GDB includes speedups for downloading and stepping MIPS systems using
4491 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4492 and more efficient S-record downloading.
4494 * Memory use reductions and statistics collection
4496 GDB now uses less memory and reports statistics about memory usage.
4497 Try the `maint print statistics' command, for example.
4499 *** Changes in GDB-4.15:
4501 * Psymtabs for XCOFF
4503 The symbol reader for AIX GDB now uses partial symbol tables. This
4504 can greatly improve startup time, especially for large executables.
4506 * Remote targets use caching
4508 Remote targets now use a data cache to speed up communication with the
4509 remote side. The data cache could lead to incorrect results because
4510 it doesn't know about volatile variables, thus making it impossible to
4511 debug targets which use memory mapped I/O devices. `set remotecache
4512 off' turns the the data cache off.
4514 * Remote targets may have threads
4516 The standard remote protocol now includes support for multiple threads
4517 in the target system, using new protocol commands 'H' and 'T'. See
4518 gdb/remote.c for details.
4522 If GDB is configured with `--enable-netrom', then it will include
4523 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4524 acts as though it is a bank of ROM on the target board, but you can
4525 write into it over the network. GDB's support consists only of
4526 support for fast loading into the emulated ROM; to debug, you must use
4527 another protocol, such as standard remote protocol. The usual
4528 sequence is something like
4530 target nrom <netrom-hostname>
4532 target remote <netrom-hostname>:1235
4536 GDB now includes support for the Apple Macintosh, as a host only. It
4537 may be run as either an MPW tool or as a standalone application, and
4538 it can debug through the serial port. All the usual GDB commands are
4539 available, but to the target command, you must supply "serial" as the
4540 device type instead of "/dev/ttyXX". See mpw-README in the main
4541 directory for more information on how to build. The MPW configuration
4542 scripts */mpw-config.in support only a few targets, and only the
4543 mips-idt-ecoff target has been tested.
4547 GDB configuration now uses autoconf. This is not user-visible,
4548 but does simplify configuration and building.
4552 GDB now supports hpux10.
4554 *** Changes in GDB-4.14:
4556 * New native configurations
4558 x86 FreeBSD i[345]86-*-freebsd
4559 x86 NetBSD i[345]86-*-netbsd
4560 NS32k NetBSD ns32k-*-netbsd
4561 Sparc NetBSD sparc-*-netbsd
4565 A29K VxWorks a29k-*-vxworks
4566 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4567 CPU32 EST-300 emulator m68*-*-est*
4568 PowerPC ELF powerpc-*-elf
4571 * Alpha OSF/1 support for procfs
4573 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4574 possible to attach to running processes. As the mounting of the /proc
4575 filesystem is optional on the Alpha, GDB automatically determines
4576 the availability of /proc during startup. This can lead to problems
4577 if /proc is unmounted after GDB has been started.
4579 * Arguments to user-defined commands
4581 User commands may accept up to 10 arguments separated by whitespace.
4582 Arguments are accessed within the user command via $arg0..$arg9. A
4585 print $arg0 + $arg1 + $arg2
4587 To execute the command use:
4590 Defines the command "adder" which prints the sum of its three arguments.
4591 Note the arguments are text substitutions, so they may reference variables,
4592 use complex expressions, or even perform inferior function calls.
4594 * New `if' and `while' commands
4596 This makes it possible to write more sophisticated user-defined
4597 commands. Both commands take a single argument, which is the
4598 expression to evaluate, and must be followed by the commands to
4599 execute, one per line, if the expression is nonzero, the list being
4600 terminated by the word `end'. The `if' command list may include an
4601 `else' word, which causes the following commands to be executed only
4602 if the expression is zero.
4604 * Fortran source language mode
4606 GDB now includes partial support for Fortran 77. It will recognize
4607 Fortran programs and can evaluate a subset of Fortran expressions, but
4608 variables and functions may not be handled correctly. GDB will work
4609 with G77, but does not yet know much about symbols emitted by other
4612 * Better HPUX support
4614 Most debugging facilities now work on dynamic executables for HPPAs
4615 running hpux9 or later. You can attach to running dynamically linked
4616 processes, but by default the dynamic libraries will be read-only, so
4617 for instance you won't be able to put breakpoints in them. To change
4618 that behavior do the following before running the program:
4624 This will cause the libraries to be mapped private and read-write.
4625 To revert to the normal behavior, do this:
4631 You cannot set breakpoints or examine data in the library until after
4632 the library is loaded if the function/data symbols do not have
4635 GDB can now also read debug symbols produced by the HP C compiler on
4636 HPPAs (sorry, no C++, Fortran or 68k support).
4638 * Target byte order now dynamically selectable
4640 You can choose which byte order to use with a target system, via the
4641 commands "set endian big" and "set endian little", and you can see the
4642 current setting by using "show endian". You can also give the command
4643 "set endian auto", in which case GDB will use the byte order
4644 associated with the executable. Currently, only embedded MIPS
4645 configurations support dynamic selection of target byte order.
4647 * New DOS host serial code
4649 This version uses DPMI interrupts to handle buffered I/O, so you
4650 no longer need to run asynctsr when debugging boards connected to
4653 *** Changes in GDB-4.13:
4655 * New "complete" command
4657 This lists all the possible completions for the rest of the line, if it
4658 were to be given as a command itself. This is intended for use by emacs.
4660 * Trailing space optional in prompt
4662 "set prompt" no longer adds a space for you after the prompt you set. This
4663 allows you to set a prompt which ends in a space or one that does not.
4665 * Breakpoint hit counts
4667 "info break" now displays a count of the number of times the breakpoint
4668 has been hit. This is especially useful in conjunction with "ignore"; you
4669 can ignore a large number of breakpoint hits, look at the breakpoint info
4670 to see how many times the breakpoint was hit, then run again, ignoring one
4671 less than that number, and this will get you quickly to the last hit of
4674 * Ability to stop printing at NULL character
4676 "set print null-stop" will cause GDB to stop printing the characters of
4677 an array when the first NULL is encountered. This is useful when large
4678 arrays actually contain only short strings.
4680 * Shared library breakpoints
4682 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4683 breakpoints in shared libraries before the executable is run.
4685 * Hardware watchpoints
4687 There is a new hardware breakpoint for the watch command for sparclite
4688 targets. See gdb/sparclite/hw_breakpoint.note.
4690 Hardware watchpoints are also now supported under GNU/Linux.
4694 Annotations have been added. These are for use with graphical interfaces,
4695 and are still experimental. Currently only gdba.el uses these.
4697 * Improved Irix 5 support
4699 GDB now works properly with Irix 5.2.
4701 * Improved HPPA support
4703 GDB now works properly with the latest GCC and GAS.
4705 * New native configurations
4707 Sequent PTX4 i[34]86-sequent-ptx4
4708 HPPA running OSF/1 hppa*-*-osf*
4709 Atari TT running SVR4 m68*-*-sysv4*
4710 RS/6000 LynxOS rs6000-*-lynxos*
4714 OS/9000 i[34]86-*-os9k
4715 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4718 * Hitachi SH7000 and E7000-PC ICE support
4720 There is now support for communicating with the Hitachi E7000-PC ICE.
4721 This is available automatically when GDB is configured for the SH.
4725 As usual, a variety of small fixes and improvements, both generic
4726 and configuration-specific. See the ChangeLog for more detail.
4728 *** Changes in GDB-4.12:
4730 * Irix 5 is now supported
4734 GDB-4.12 on the HPPA has a number of changes which make it unable
4735 to debug the output from the currently released versions of GCC and
4736 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4737 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4738 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4741 *** Changes in GDB-4.11:
4743 * User visible changes:
4747 The "set remotedebug" option is now consistent between the mips remote
4748 target, remote targets using the gdb-specific protocol, UDI (AMD's
4749 debug protocol for the 29k) and the 88k bug monitor. It is now an
4750 integer specifying a debug level (normally 0 or 1, but 2 means more
4751 debugging info for the mips target).
4753 * DEC Alpha native support
4755 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4756 debug info, but GDB works fairly well with the DEC compiler and should
4757 work with a future GCC release. See the README file for a few
4758 Alpha-specific notes.
4760 * Preliminary thread implementation
4762 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4764 * LynxOS native and target support for 386
4766 This release has been hosted on LynxOS 2.2, and also can be configured
4767 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4770 * Improvements in C++ mangling/demangling.
4772 This release has much better g++ debugging, specifically in name
4773 mangling/demangling, virtual function calls, print virtual table,
4774 call methods, ...etc.
4776 *** Changes in GDB-4.10:
4778 * User visible changes:
4780 Remote debugging using the GDB-specific (`target remote') protocol now
4781 supports the `load' command. This is only useful if you have some
4782 other way of getting the stub to the target system, and you can put it
4783 somewhere in memory where it won't get clobbered by the download.
4785 Filename completion now works.
4787 When run under emacs mode, the "info line" command now causes the
4788 arrow to point to the line specified. Also, "info line" prints
4789 addresses in symbolic form (as well as hex).
4791 All vxworks based targets now support a user settable option, called
4792 vxworks-timeout. This option represents the number of seconds gdb
4793 should wait for responses to rpc's. You might want to use this if
4794 your vxworks target is, perhaps, a slow software simulator or happens
4795 to be on the far side of a thin network line.
4799 This release contains support for using a DEC alpha as a GDB host for
4800 cross debugging. Native alpha debugging is not supported yet.
4803 *** Changes in GDB-4.9:
4807 This is the first GDB release which is accompanied by a matching testsuite.
4808 The testsuite requires installation of dejagnu, which should be available
4809 via ftp from most sites that carry GNU software.
4813 'Cfront' style demangling has had its name changed to 'ARM' style, to
4814 emphasize that it was written from the specifications in the C++ Annotated
4815 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4816 disclaimers, it still generated too much confusion with users attempting to
4817 use gdb with AT&T cfront.
4821 GDB now uses a standard remote interface to a simulator library.
4822 So far, the library contains simulators for the Zilog Z8001/2, the
4823 Hitachi H8/300, H8/500 and Super-H.
4825 * New targets supported
4827 H8/300 simulator h8300-hitachi-hms or h8300hms
4828 H8/500 simulator h8500-hitachi-hms or h8500hms
4829 SH simulator sh-hitachi-hms or sh
4830 Z8000 simulator z8k-zilog-none or z8ksim
4831 IDT MIPS board over serial line mips-idt-ecoff
4833 Cross-debugging to GO32 targets is supported. It requires a custom
4834 version of the i386-stub.c module which is integrated with the
4835 GO32 memory extender.
4837 * New remote protocols
4839 MIPS remote debugging protocol.
4841 * New source languages supported
4843 This version includes preliminary support for Chill, a Pascal like language
4844 used by telecommunications companies. Chill support is also being integrated
4845 into the GNU compiler, but we don't know when it will be publically available.
4848 *** Changes in GDB-4.8:
4850 * HP Precision Architecture supported
4852 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4853 version of this support was available as a set of patches from the
4854 University of Utah. GDB does not support debugging of programs
4855 compiled with the HP compiler, because HP will not document their file
4856 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4857 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4859 Many problems in the preliminary version have been fixed.
4861 * Faster and better demangling
4863 We have improved template demangling and fixed numerous bugs in the GNU style
4864 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4865 character types (wchar_t) are now supported. Demangling of each symbol is now
4866 only done once, and is cached when the symbol table for a file is read in.
4867 This results in a small increase in memory usage for C programs, a moderate
4868 increase in memory usage for C++ programs, and a fantastic speedup in
4871 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4872 from the specifications in the Annotated Reference Manual, which AT&T's
4873 compiler does not actually implement.
4875 * G++ multiple inheritance compiler problem
4877 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4878 inheritance lattices was reworked to properly discover ambiguities. We
4879 recently found an example which causes this new algorithm to fail in a
4880 very subtle way, producing bad debug information for those classes.
4881 The file 'gcc.patch' (in this directory) can be applied to gcc to
4882 circumvent the problem. A future GCC release will contain a complete
4885 The previous G++ debug info problem (mentioned below for the gdb-4.7
4886 release) is fixed in gcc version 2.3.2.
4888 * Improved configure script
4890 The `configure' script will now attempt to guess your system type if
4891 you don't supply a host system type. The old scheme of supplying a
4892 host system triplet is preferable over using this. All the magic is
4893 done in the new `config.guess' script. Examine it for details.
4895 We have also brought our configure script much more in line with the FSF's
4896 version. It now supports the --with-xxx options. In particular,
4897 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4898 The resulting GDB will not be able to read arbitrary object file formats --
4899 only the format ``expected'' to be used on the configured target system.
4900 We hope to make this the default in a future release.
4902 * Documentation improvements
4904 There's new internal documentation on how to modify GDB, and how to
4905 produce clean changes to the code. We implore people to read it
4906 before submitting changes.
4908 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4909 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4910 `info' files are also provided. To build `info' files from scratch,
4911 you will need the latest `makeinfo' release, which will be available in
4912 a future texinfo-X.Y release.
4914 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4915 We're not sure exactly which versions have this problem, but it has
4916 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4917 or better. If that isn't possible, there is a patch in
4918 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4919 around this problem.
4923 GDB now supports array constants that can be used in expressions typed in by
4924 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4925 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4928 The new directory `gdb/sparclite' contains a program that demonstrates
4929 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4931 * New native hosts supported
4933 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4934 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4936 * New targets supported
4938 AMD 29k family via UDI a29k-amd-udi or udi29k
4940 * New file formats supported
4942 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4943 HPUX core files, and SCO 3.2v2 core files.
4947 Attaching to processes now works again; thanks for the many bug reports.
4949 We have also stomped on a bunch of core dumps caused by
4950 printf_filtered("%s") problems.
4952 We eliminated a copyright problem on the rpc and ptrace header files
4953 for VxWorks, which was discovered at the last minute during the 4.7
4954 release. You should now be able to build a VxWorks GDB.
4956 You can now interrupt gdb while an attached process is running. This
4957 will cause the attached process to stop, and give control back to GDB.
4959 We fixed problems caused by using too many file descriptors
4960 for reading symbols from object files and libraries. This was
4961 especially a problem for programs that used many (~100) shared
4964 The `step' command now only enters a subroutine if there is line number
4965 information for the subroutine. Otherwise it acts like the `next'
4966 command. Previously, `step' would enter subroutines if there was
4967 any debugging information about the routine. This avoids problems
4968 when using `cc -g1' on MIPS machines.
4970 * Internal improvements
4972 GDB's internal interfaces have been improved to make it easier to support
4973 debugging of multiple languages in the future.
4975 GDB now uses a common structure for symbol information internally.
4976 Minimal symbols (derived from linkage symbols in object files), partial
4977 symbols (from a quick scan of debug information), and full symbols
4978 contain a common subset of information, making it easier to write
4979 shared code that handles any of them.
4981 * New command line options
4983 We now accept --silent as an alias for --quiet.
4987 The memory-mapped-malloc library is now licensed under the GNU Library
4988 General Public License.
4990 *** Changes in GDB-4.7:
4992 * Host/native/target split
4994 GDB has had some major internal surgery to untangle the support for
4995 hosts and remote targets. Now, when you configure GDB for a remote
4996 target, it will no longer load in all of the support for debugging
4997 local programs on the host. When fully completed and tested, this will
4998 ensure that arbitrary host/target combinations are possible.
5000 The primary conceptual shift is to separate the non-portable code in
5001 GDB into three categories. Host specific code is required any time GDB
5002 is compiled on that host, regardless of the target. Target specific
5003 code relates to the peculiarities of the target, but can be compiled on
5004 any host. Native specific code is everything else: it can only be
5005 built when the host and target are the same system. Child process
5006 handling and core file support are two common `native' examples.
5008 GDB's use of /proc for controlling Unix child processes is now cleaner.
5009 It has been split out into a single module under the `target_ops' vector,
5010 plus two native-dependent functions for each system that uses /proc.
5012 * New hosts supported
5014 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5015 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5016 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5018 * New targets supported
5020 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5021 68030 and CPU32 m68030-*-*, m68332-*-*
5023 * New native hosts supported
5025 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5026 (386bsd is not well tested yet)
5027 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5029 * New file formats supported
5031 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5032 supports reading of `a.out.adobe' object files, which are an a.out
5033 format extended with minimal information about multiple sections.
5037 `show copying' is the same as the old `info copying'.
5038 `show warranty' is the same as `info warrantee'.
5039 These were renamed for consistency. The old commands continue to work.
5041 `info handle' is a new alias for `info signals'.
5043 You can now define pre-command hooks, which attach arbitrary command
5044 scripts to any command. The commands in the hook will be executed
5045 prior to the user's command. You can also create a hook which will be
5046 executed whenever the program stops. See gdb.texinfo.
5050 We now deal with Cfront style name mangling, and can even extract type
5051 info from mangled symbols. GDB can automatically figure out which
5052 symbol mangling style your C++ compiler uses.
5054 Calling of methods and virtual functions has been improved as well.
5058 The crash that occured when debugging Sun Ansi-C compiled binaries is
5059 fixed. This was due to mishandling of the extra N_SO stabs output
5062 We also finally got Ultrix 4.2 running in house, and fixed core file
5063 support, with help from a dozen people on the net.
5065 John M. Farrell discovered that the reason that single-stepping was so
5066 slow on all of the Mips based platforms (primarily SGI and DEC) was
5067 that we were trying to demangle and lookup a symbol used for internal
5068 purposes on every instruction that was being stepped through. Changing
5069 the name of that symbol so that it couldn't be mistaken for a C++
5070 mangled symbol sped things up a great deal.
5072 Rich Pixley sped up symbol lookups in general by getting much smarter
5073 about when C++ symbol mangling is necessary. This should make symbol
5074 completion (TAB on the command line) much faster. It's not as fast as
5075 we'd like, but it's significantly faster than gdb-4.6.
5079 A new user controllable variable 'call_scratch_address' can
5080 specify the location of a scratch area to be used when GDB
5081 calls a function in the target. This is necessary because the
5082 usual method of putting the scratch area on the stack does not work
5083 in systems that have separate instruction and data spaces.
5085 We integrated changes to support the 29k UDI (Universal Debugger
5086 Interface), but discovered at the last minute that we didn't have all
5087 of the appropriate copyright paperwork. We are working with AMD to
5088 resolve this, and hope to have it available soon.
5092 We have sped up the remote serial line protocol, especially for targets
5093 with lots of registers. It now supports a new `expedited status' ('T')
5094 message which can be used in place of the existing 'S' status message.
5095 This allows the remote stub to send only the registers that GDB
5096 needs to make a quick decision about single-stepping or conditional
5097 breakpoints, eliminating the need to fetch the entire register set for
5098 each instruction being stepped through.
5100 The GDB remote serial protocol now implements a write-through cache for
5101 registers, only re-reading the registers if the target has run.
5103 There is also a new remote serial stub for SPARC processors. You can
5104 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5105 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5106 processor with a serial port.
5110 Configure.in files have become much easier to read and modify. A new
5111 `table driven' format makes it more obvious what configurations are
5112 supported, and what files each one uses.
5116 There is a new opcodes library which will eventually contain all of the
5117 disassembly routines and opcode tables. At present, it only contains
5118 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5119 disassembler (binutils/objdump) to share these routines.
5121 The libiberty library is now copylefted under the GNU Library General
5122 Public License. This allows more liberal use, and was done so libg++
5123 can use it. This makes no difference to GDB, since the Library License
5124 grants all the rights from the General Public License.
5128 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5129 reference to the stabs symbol info used by the debugger. It is (as far
5130 as we know) the only published document on this fascinating topic. We
5131 encourage you to read it, compare it to the stabs information on your
5132 system, and send improvements on the document in general (to
5133 bug-gdb@prep.ai.mit.edu).
5135 And, of course, many bugs have been fixed.
5138 *** Changes in GDB-4.6:
5140 * Better support for C++ function names
5142 GDB now accepts as input the "demangled form" of C++ overloaded function
5143 names and member function names, and can do command completion on such names
5144 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5145 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5146 Make use of command completion, it is your friend.
5148 GDB also now accepts a variety of C++ mangled symbol formats. They are
5149 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5150 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5151 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5152 for the list of formats.
5154 * G++ symbol mangling problem
5156 Recent versions of gcc have a bug in how they emit debugging information for
5157 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5158 directory) can be applied to gcc to fix the problem. Alternatively, if you
5159 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5160 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5161 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5164 * New 'maintenance' command
5166 All of the commands related to hacking GDB internals have been moved out of
5167 the main command set, and now live behind the 'maintenance' command. This
5168 can also be abbreviated as 'mt'. The following changes were made:
5170 dump-me -> maintenance dump-me
5171 info all-breakpoints -> maintenance info breakpoints
5172 printmsyms -> maintenance print msyms
5173 printobjfiles -> maintenance print objfiles
5174 printpsyms -> maintenance print psymbols
5175 printsyms -> maintenance print symbols
5177 The following commands are new:
5179 maintenance demangle Call internal GDB demangler routine to
5180 demangle a C++ link name and prints the result.
5181 maintenance print type Print a type chain for a given symbol
5183 * Change to .gdbinit file processing
5185 We now read the $HOME/.gdbinit file before processing the argv arguments
5186 (e.g. reading symbol files or core files). This allows global parameters to
5187 be set, which will apply during the symbol reading. The ./.gdbinit is still
5188 read after argv processing.
5190 * New hosts supported
5192 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5194 GNU/Linux support i386-unknown-linux or linux
5196 We are also including code to support the HP/PA running BSD and HPUX. This
5197 is almost guaranteed not to work, as we didn't have time to test or build it
5198 for this release. We are including it so that the more adventurous (or
5199 masochistic) of you can play with it. We also had major problems with the
5200 fact that the compiler that we got from HP doesn't support the -g option.
5203 * New targets supported
5205 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5207 * More smarts about finding #include files
5209 GDB now remembers the compilation directory for all include files, and for
5210 all files from which C is generated (like yacc and lex sources). This
5211 greatly improves GDB's ability to find yacc/lex sources, and include files,
5212 especially if you are debugging your program from a directory different from
5213 the one that contains your sources.
5215 We also fixed a bug which caused difficulty with listing and setting
5216 breakpoints in include files which contain C code. (In the past, you had to
5217 try twice in order to list an include file that you hadn't looked at before.)
5219 * Interesting infernals change
5221 GDB now deals with arbitrary numbers of sections, where the symbols for each
5222 section must be relocated relative to that section's landing place in the
5223 target's address space. This work was needed to support ELF with embedded
5224 stabs used by Solaris-2.0.
5226 * Bug fixes (of course!)
5228 There have been loads of fixes for the following things:
5229 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5230 i960, stabs, DOS(GO32), procfs, etc...
5232 See the ChangeLog for details.
5234 *** Changes in GDB-4.5:
5236 * New machines supported (host and target)
5238 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5240 SGI Irix-4.x mips-sgi-irix4 or iris4
5242 * New malloc package
5244 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5245 Mmalloc is capable of handling mutiple heaps of memory. It is also
5246 capable of saving a heap to a file, and then mapping it back in later.
5247 This can be used to greatly speedup the startup of GDB by using a
5248 pre-parsed symbol table which lives in a mmalloc managed heap. For
5249 more details, please read mmalloc/mmalloc.texi.
5253 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5254 'help info proc' for details.
5256 * MIPS ecoff symbol table format
5258 The code that reads MIPS symbol table format is now supported on all hosts.
5259 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5262 * File name changes for MS-DOS
5264 Many files in the config directories have been renamed to make it easier to
5265 support GDB on MS-DOSe systems (which have very restrictive file name
5266 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5267 environment) is close to working but has some remaining problems. Note
5268 that debugging of DOS programs is not supported, due to limitations
5269 in the ``operating system'', but it can be used to host cross-debugging.
5271 * Cross byte order fixes
5273 Many fixes have been made to support cross debugging of Sparc and MIPS
5274 targets from hosts whose byte order differs.
5276 * New -mapped and -readnow options
5278 If memory-mapped files are available on your system through the 'mmap'
5279 system call, you can use the -mapped option on the `file' or
5280 `symbol-file' commands to cause GDB to write the symbols from your
5281 program into a reusable file. If the program you are debugging is
5282 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5283 Future GDB debugging sessions will notice the presence of this file,
5284 and will quickly map in symbol information from it, rather than reading
5285 the symbol table from the executable program. Using the '-mapped'
5286 option in a GDB `file' or `symbol-file' command has the same effect as
5287 starting GDB with the '-mapped' command-line option.
5289 You can cause GDB to read the entire symbol table immediately by using
5290 the '-readnow' option with any of the commands that load symbol table
5291 information (or on the GDB command line). This makes the command
5292 slower, but makes future operations faster.
5294 The -mapped and -readnow options are typically combined in order to
5295 build a `fred.syms' file that contains complete symbol information.
5296 A simple GDB invocation to do nothing but build a `.syms' file for future
5299 gdb -batch -nx -mapped -readnow programname
5301 The `.syms' file is specific to the host machine on which GDB is run.
5302 It holds an exact image of GDB's internal symbol table. It cannot be
5303 shared across multiple host platforms.
5305 * longjmp() handling
5307 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5308 siglongjmp() without losing control. This feature has not yet been ported to
5309 all systems. It currently works on many 386 platforms, all MIPS-based
5310 platforms (SGI, DECstation, etc), and Sun3/4.
5314 Preliminary work has been put in to support the new Solaris OS from Sun. At
5315 this time, it can control and debug processes, but it is not capable of
5320 As always, many many bug fixes. The major areas were with g++, and mipsread.
5321 People using the MIPS-based platforms should experience fewer mysterious
5322 crashes and trashed symbol tables.
5324 *** Changes in GDB-4.4:
5326 * New machines supported (host and target)
5328 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5330 BSD Reno on Vax vax-dec-bsd
5331 Ultrix on Vax vax-dec-ultrix
5333 * New machines supported (target)
5335 AMD 29000 embedded, using EBMON a29k-none-none
5339 GDB continues to improve its handling of C++. `References' work better.
5340 The demangler has also been improved, and now deals with symbols mangled as
5341 per the Annotated C++ Reference Guide.
5343 GDB also now handles `stabs' symbol information embedded in MIPS
5344 `ecoff' symbol tables. Since the ecoff format was not easily
5345 extensible to handle new languages such as C++, this appeared to be a
5346 good way to put C++ debugging info into MIPS binaries. This option
5347 will be supported in the GNU C compiler, version 2, when it is
5350 * New features for SVR4
5352 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5353 shared libraries. Debugging dynamically linked programs should present
5354 only minor differences from debugging statically linked programs.
5356 The `info proc' command will print out information about any process
5357 on an SVR4 system (including the one you are debugging). At the moment,
5358 it prints the address mappings of the process.
5360 If you bring up GDB on another SVR4 system, please send mail to
5361 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5363 * Better dynamic linking support in SunOS
5365 Reading symbols from shared libraries which contain debugging symbols
5366 now works properly. However, there remain issues such as automatic
5367 skipping of `transfer vector' code during function calls, which
5368 make it harder to debug code in a shared library, than to debug the
5369 same code linked statically.
5373 GDB is now using the latest `getopt' routines from the FSF. This
5374 version accepts the -- prefix for options with long names. GDB will
5375 continue to accept the old forms (-option and +option) as well.
5376 Various single letter abbreviations for options have been explicity
5377 added to the option table so that they won't get overshadowed in the
5378 future by other options that begin with the same letter.
5382 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5383 Many assorted bugs have been handled. Many more remain to be handled.
5384 See the various ChangeLog files (primarily in gdb and bfd) for details.
5387 *** Changes in GDB-4.3:
5389 * New machines supported (host and target)
5391 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5392 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5393 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5395 * Almost SCO Unix support
5397 We had hoped to support:
5398 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5399 (except for core file support), but we discovered very late in the release
5400 that it has problems with process groups that render gdb unusable. Sorry
5401 about that. I encourage people to fix it and post the fixes.
5403 * Preliminary ELF and DWARF support
5405 GDB can read ELF object files on System V Release 4, and can handle
5406 debugging records for C, in DWARF format, in ELF files. This support
5407 is preliminary. If you bring up GDB on another SVR4 system, please
5408 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5413 GDB now uses the latest `readline' library. One user-visible change
5414 is that two tabs will list possible command completions, which previously
5415 required typing M-? (meta-question mark, or ESC ?).
5419 The `stepi' bug that many of you noticed has been squashed.
5420 Many bugs in C++ have been handled. Many more remain to be handled.
5421 See the various ChangeLog files (primarily in gdb and bfd) for details.
5423 * State of the MIPS world (in case you wondered):
5425 GDB can understand the symbol tables emitted by the compilers
5426 supplied by most vendors of MIPS-based machines, including DEC. These
5427 symbol tables are in a format that essentially nobody else uses.
5429 Some versions of gcc come with an assembler post-processor called
5430 mips-tfile. This program is required if you want to do source-level
5431 debugging of gcc-compiled programs. I believe FSF does not ship
5432 mips-tfile with gcc version 1, but it will eventually come with gcc
5435 Debugging of g++ output remains a problem. g++ version 1.xx does not
5436 really support it at all. (If you're lucky, you should be able to get
5437 line numbers and stack traces to work, but no parameters or local
5438 variables.) With some work it should be possible to improve the
5441 When gcc version 2 is released, you will have somewhat better luck.
5442 However, even then you will get confusing results for inheritance and
5445 We will eventually provide full debugging of g++ output on
5446 DECstations. This will probably involve some kind of stabs-in-ecoff
5447 encapulation, but the details have not been worked out yet.
5450 *** Changes in GDB-4.2:
5452 * Improved configuration
5454 Only one copy of `configure' exists now, and it is not self-modifying.
5455 Porting BFD is simpler.
5459 The `step' and `next' commands now only stop at the first instruction
5460 of a source line. This prevents the multiple stops that used to occur
5461 in switch statements, for-loops, etc. `Step' continues to stop if a
5462 function that has debugging information is called within the line.
5466 Lots of small bugs fixed. More remain.
5468 * New host supported (not target)
5470 Intel 386 PC clone running Mach i386-none-mach
5473 *** Changes in GDB-4.1:
5475 * Multiple source language support
5477 GDB now has internal scaffolding to handle several source languages.
5478 It determines the type of each source file from its filename extension,
5479 and will switch expression parsing and number formatting to match the
5480 language of the function in the currently selected stack frame.
5481 You can also specifically set the language to be used, with
5482 `set language c' or `set language modula-2'.
5486 GDB now has preliminary support for the GNU Modula-2 compiler,
5487 currently under development at the State University of New York at
5488 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5489 continue through the fall of 1991 and into 1992.
5491 Other Modula-2 compilers are currently not supported, and attempting to
5492 debug programs compiled with them will likely result in an error as the
5493 symbol table is read. Feel free to work on it, though!
5495 There are hooks in GDB for strict type checking and range checking,
5496 in the `Modula-2 philosophy', but they do not currently work.
5500 GDB can now write to executable and core files (e.g. patch
5501 a variable's value). You must turn this switch on, specify
5502 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5503 by assigning a new value to a variable. Modifications take
5506 * Automatic SunOS shared library reading
5508 When you run your program, GDB automatically determines where its
5509 shared libraries (if any) have been loaded, and reads their symbols.
5510 The `share' command is no longer needed. This also works when
5511 examining core files.
5515 You can specify the number of lines that the `list' command shows.
5518 * New machines supported (host and target)
5520 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5521 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5522 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5524 * New hosts supported (not targets)
5526 IBM RT/PC: romp-ibm-aix or rtpc
5528 * New targets supported (not hosts)
5530 AMD 29000 embedded with COFF a29k-none-coff
5531 AMD 29000 embedded with a.out a29k-none-aout
5532 Ultracomputer remote kernel debug a29k-nyu-kern
5534 * New remote interfaces
5540 *** Changes in GDB-4.0:
5544 Wide output is wrapped at good places to make the output more readable.
5546 Gdb now supports cross-debugging from a host machine of one type to a
5547 target machine of another type. Communication with the target system
5548 is over serial lines. The ``target'' command handles connecting to the
5549 remote system; the ``load'' command will download a program into the
5550 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5551 also supports debugging of realtime processes running under VxWorks,
5552 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5553 stub on the target system.
5555 New CPUs supported include the AMD 29000 and Intel 960.
5557 GDB now reads object files and symbol tables via a ``binary file''
5558 library, which allows a single copy of GDB to debug programs of multiple
5559 object file types such as a.out and coff.
5561 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5562 refcard.dvi and refcard.ps are available to format it).
5565 * Control-Variable user interface simplified
5567 All variables that control the operation of the debugger can be set
5568 by the ``set'' command, and displayed by the ``show'' command.
5570 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5571 ``Show prompt'' produces the response:
5572 Gdb's prompt is new-gdb=>.
5574 What follows are the NEW set commands. The command ``help set'' will
5575 print a complete list of old and new set commands. ``help set FOO''
5576 will give a longer description of the variable FOO. ``show'' will show
5577 all of the variable descriptions and their current settings.
5579 confirm on/off: Enables warning questions for operations that are
5580 hard to recover from, e.g. rerunning the program while
5581 it is already running. Default is ON.
5583 editing on/off: Enables EMACS style command line editing
5584 of input. Previous lines can be recalled with
5585 control-P, the current line can be edited with control-B,
5586 you can search for commands with control-R, etc.
5589 history filename NAME: NAME is where the gdb command history
5590 will be stored. The default is .gdb_history,
5591 or the value of the environment variable
5594 history size N: The size, in commands, of the command history. The
5595 default is 256, or the value of the environment variable
5598 history save on/off: If this value is set to ON, the history file will
5599 be saved after exiting gdb. If set to OFF, the
5600 file will not be saved. The default is OFF.
5602 history expansion on/off: If this value is set to ON, then csh-like
5603 history expansion will be performed on
5604 command line input. The default is OFF.
5606 radix N: Sets the default radix for input and output. It can be set
5607 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5608 in the current radix, so "set radix 10" is always a no-op.
5610 height N: This integer value is the number of lines on a page. Default
5611 is 24, the current `stty rows'' setting, or the ``li#''
5612 setting from the termcap entry matching the environment
5615 width N: This integer value is the number of characters on a line.
5616 Default is 80, the current `stty cols'' setting, or the ``co#''
5617 setting from the termcap entry matching the environment
5620 Note: ``set screensize'' is obsolete. Use ``set height'' and
5621 ``set width'' instead.
5623 print address on/off: Print memory addresses in various command displays,
5624 such as stack traces and structure values. Gdb looks
5625 more ``symbolic'' if you turn this off; it looks more
5626 ``machine level'' with it on. Default is ON.
5628 print array on/off: Prettyprint arrays. New convenient format! Default
5631 print demangle on/off: Print C++ symbols in "source" form if on,
5634 print asm-demangle on/off: Same, for assembler level printouts
5637 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5640 * Support for Epoch Environment.
5642 The epoch environment is a version of Emacs v18 with windowing. One
5643 new command, ``inspect'', is identical to ``print'', except that if you
5644 are running in the epoch environment, the value is printed in its own
5648 * Support for Shared Libraries
5650 GDB can now debug programs and core files that use SunOS shared libraries.
5651 Symbols from a shared library cannot be referenced
5652 before the shared library has been linked with the program (this
5653 happens after you type ``run'' and before the function main() is entered).
5654 At any time after this linking (including when examining core files
5655 from dynamically linked programs), gdb reads the symbols from each
5656 shared library when you type the ``sharedlibrary'' command.
5657 It can be abbreviated ``share''.
5659 sharedlibrary REGEXP: Load shared object library symbols for files
5660 matching a unix regular expression. No argument
5661 indicates to load symbols for all shared libraries.
5663 info sharedlibrary: Status of loaded shared libraries.
5668 A watchpoint stops execution of a program whenever the value of an
5669 expression changes. Checking for this slows down execution
5670 tremendously whenever you are in the scope of the expression, but is
5671 quite useful for catching tough ``bit-spreader'' or pointer misuse
5672 problems. Some machines such as the 386 have hardware for doing this
5673 more quickly, and future versions of gdb will use this hardware.
5675 watch EXP: Set a watchpoint (breakpoint) for an expression.
5677 info watchpoints: Information about your watchpoints.
5679 delete N: Deletes watchpoint number N (same as breakpoints).
5680 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5681 enable N: Re-enables watchpoint number N (same as breakpoints).
5684 * C++ multiple inheritance
5686 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5689 * C++ exception handling
5691 Gdb now supports limited C++ exception handling. Besides the existing
5692 ability to breakpoint on an exception handler, gdb can breakpoint on
5693 the raising of an exception (before the stack is peeled back to the
5696 catch FOO: If there is a FOO exception handler in the dynamic scope,
5697 set a breakpoint to catch exceptions which may be raised there.
5698 Multiple exceptions (``catch foo bar baz'') may be caught.
5700 info catch: Lists all exceptions which may be caught in the
5701 current stack frame.
5704 * Minor command changes
5706 The command ``call func (arg, arg, ...)'' now acts like the print
5707 command, except it does not print or save a value if the function's result
5708 is void. This is similar to dbx usage.
5710 The ``up'' and ``down'' commands now always print the frame they end up
5711 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5712 frames without printing.
5714 * New directory command
5716 'dir' now adds directories to the FRONT of the source search path.
5717 The path starts off empty. Source files that contain debug information
5718 about the directory in which they were compiled can be found even
5719 with an empty path; Sun CC and GCC include this information. If GDB can't
5720 find your source file in the current directory, type "dir .".
5722 * Configuring GDB for compilation
5724 For normal use, type ``./configure host''. See README or gdb.texinfo
5727 GDB now handles cross debugging. If you are remotely debugging between
5728 two different machines, type ``./configure host -target=targ''.
5729 Host is the machine where GDB will run; targ is the machine
5730 where the program that you are debugging will run.
5732 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5734 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5736 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5737 $k0 - $k7 on GNU/Linux.