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 maint set target-async (on|off)
75 maint show target-async
76 This controls whether GDB targets operate in syncronous or
77 asyncronous mode. Normally the default is asyncronous, if it is
78 available; but this can be changed to more easily debug problems
79 occurring only in syncronous mode.
83 Control whether MI asynchronous mode is preferred. This supersedes
84 "set target-async" of previous GDB versions.
86 * "set target-async" is deprecated as a CLI option and is now an alias
87 for "set mi-async" (only puts MI into async mode).
89 * Background execution commands (e.g., "c&", "s&", etc.) are now
90 possible ``out of the box'' if the target supports them. Previously
91 the user would need to explicitly enable the possibility with the
92 "set target-async on" command.
94 * New features in the GDB remote stub, GDBserver
96 ** New option --debug-format=option1[,option2,...] allows one to add
97 additional text to each output. At present only timestamps
98 are supported: --debug-format=timestamps.
99 Timestamps can also be turned on with the
100 "monitor set debug-format timestamps" command from GDB.
102 * The 'record instruction-history' command now starts counting instructions
103 at one. This also affects the instruction ranges reported by the
104 'record function-call-history' command when given the /i modifier.
106 * The command 'record function-call-history' supports a new modifier '/c' to
107 indent the function names based on their call stack depth.
108 The fields for the '/i' and '/l' modifier have been reordered.
109 The source line range is now prefixed with 'at'.
110 The instruction range is now prefixed with 'inst'.
111 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
112 "record instruction-history" and "list" commands.
114 * The ranges given as arguments to the 'record function-call-history' and
115 'record instruction-history' commands are now inclusive.
117 * The btrace record target now supports the 'record goto' command.
118 For locations inside the execution trace, the back trace is computed
119 based on the information stored in the execution trace.
121 * The btrace record target supports limited reverse execution and replay.
122 The target does not record data and therefore does not allow reading
125 * The "catch syscall" command now works on s390*-linux* targets.
127 * The "compare-sections" command is no longer specific to target
128 remote. It now works with all targets.
130 * All native targets are now consistently called "native".
131 Consequently, the "target child", "target GNU", "target djgpp",
132 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
133 commands have been replaced with "target native". The QNX/NTO port
134 leaves the "procfs" target in place and adds a "native" target for
135 consistency with other ports. The impact on users should be minimal
136 as these commands previously either throwed an error, or were
137 no-ops. The target's name is visible in the output of the following
138 commands: "help target", "info target", "info files", "maint print
141 * The "target native" command now connects to the native target. This
142 can be used to launch native programs even when "set
143 auto-connect-native-target" is set to off.
147 qXfer:btrace:read's annex
148 The qXfer:btrace:read packet supports a new annex 'delta' to read
149 branch trace incrementally.
153 ** Valid Python operations on gdb.Value objects representing
154 structs/classes invoke the corresponding overloaded operators if
156 ** New `Xmethods' feature in the Python API. Xmethods are
157 additional methods or replacements for existing methods of a C++
158 class. This feature is useful for those cases where a method
159 defined in C++ source code could be inlined or optimized out by
160 the compiler, making it unavailable to GDB.
163 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
165 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
166 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
167 its alias "share", instead.
169 * The commands "set remotebaud" and "show remotebaud" are no longer
170 supported. Use "set serial baud" and "show serial baud" (respectively)
175 ** A new option "-gdb-set mi-async" replaces "-gdb-set
176 target-async". The latter is left as a deprecated alias of the
177 former for backward compatibility. If the target supports it,
178 CLI background execution commands are now always possible by
179 default, independently of whether the frontend stated a
180 preference for asynchronous execution with "-gdb-set mi-async".
181 Previously "-gdb-set target-async off" affected both MI execution
182 commands and CLI execution commands.
184 *** Changes in GDB 7.7
186 * Improved support for process record-replay and reverse debugging on
187 arm*-linux* targets. Support for thumb32 and syscall instruction
188 recording has been added.
190 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
192 * GDB now supports Fission DWP file format version 2.
193 http://gcc.gnu.org/wiki/DebugFission
195 * New convenience function "$_isvoid", to check whether an expression
196 is void. A void expression is an expression where the type of the
197 result is "void". For example, some convenience variables may be
198 "void" when evaluated (e.g., "$_exitcode" before the execution of
199 the program being debugged; or an undefined convenience variable).
200 Another example, when calling a function whose return type is
203 * The "maintenance print objfiles" command now takes an optional regexp.
205 * The "catch syscall" command now works on arm*-linux* targets.
207 * GDB now consistently shows "<not saved>" when printing values of
208 registers the debug info indicates have not been saved in the frame
209 and there's nowhere to retrieve them from
210 (callee-saved/call-clobbered registers):
215 (gdb) info registers rax
218 Before, the former would print "<optimized out>", and the latter
219 "*value not available*".
221 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
226 ** Frame filters and frame decorators have been added.
227 ** Temporary breakpoints are now supported.
228 ** Line tables representation has been added.
229 ** New attribute 'parent_type' for gdb.Field objects.
230 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
231 ** New attribute 'name' for gdb.Type objects.
235 Nios II ELF nios2*-*-elf
236 Nios II GNU/Linux nios2*-*-linux
237 Texas Instruments MSP430 msp430*-*-elf
239 * Removed native configurations
241 Support for these a.out NetBSD and OpenBSD obsolete configurations has
242 been removed. ELF variants of these configurations are kept supported.
244 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
245 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
246 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
247 i[34567]86-*-openbsd3.[0-3]
248 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
249 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
250 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
254 Like "catch throw", but catches a re-thrown exception.
256 Renamed from old "maint check-symtabs".
258 Perform consistency checks on symtabs.
260 Expand symtabs matching an optional regexp.
263 Display the details of GDB configure-time options.
265 maint set|show per-command
266 maint set|show per-command space
267 maint set|show per-command time
268 maint set|show per-command symtab
269 Enable display of per-command gdb resource usage.
271 remove-symbol-file FILENAME
272 remove-symbol-file -a ADDRESS
273 Remove a symbol file added via add-symbol-file. The file to remove
274 can be identified by its filename or by an address that lies within
275 the boundaries of this symbol file in memory.
278 info exceptions REGEXP
279 Display the list of Ada exceptions defined in the program being
280 debugged. If provided, only the exceptions whose names match REGEXP
285 set debug symfile off|on
287 Control display of debugging info regarding reading symbol files and
288 symbol tables within those files
290 set print raw frame-arguments
291 show print raw frame-arguments
292 Set/show whether to print frame arguments in raw mode,
293 disregarding any defined pretty-printers.
295 set remote trace-status-packet
296 show remote trace-status-packet
297 Set/show the use of remote protocol qTStatus packet.
301 Control display of debugging messages related to Nios II targets.
305 Control whether target-assisted range stepping is enabled.
307 set startup-with-shell
308 show startup-with-shell
309 Specifies whether Unix child processes are started via a shell or
314 Use the target memory cache for accesses to the code segment. This
315 improves performance of remote debugging (particularly disassembly).
317 * You can now use a literal value 'unlimited' for options that
318 interpret 0 or -1 as meaning "unlimited". E.g., "set
319 trace-buffer-size unlimited" is now an alias for "set
320 trace-buffer-size -1" and "set height unlimited" is now an alias for
323 * The "set debug symtab-create" debugging option of GDB has been changed to
324 accept a verbosity level. 0 means "off", 1 provides basic debugging
325 output, and values of 2 or greater provides more verbose output.
327 * New command-line options
329 Display the details of GDB configure-time options.
331 * The command 'tsave' can now support new option '-ctf' to save trace
332 buffer in Common Trace Format.
334 * Newly installed $prefix/bin/gcore acts as a shell interface for the
337 * GDB now implements the the C++ 'typeid' operator.
339 * The new convenience variable $_exception holds the exception being
340 thrown or caught at an exception-related catchpoint.
342 * The exception-related catchpoints, like "catch throw", now accept a
343 regular expression which can be used to filter exceptions by type.
345 * The new convenience variable $_exitsignal is automatically set to
346 the terminating signal number when the program being debugged dies
347 due to an uncaught signal.
351 ** All MI commands now accept an optional "--language" option.
352 Support for this feature can be verified by using the "-list-features"
353 command, which should contain "language-option".
355 ** The new command -info-gdb-mi-command allows the user to determine
356 whether a GDB/MI command is supported or not.
358 ** The "^error" result record returned when trying to execute an undefined
359 GDB/MI command now provides a variable named "code" whose content is the
360 "undefined-command" error code. Support for this feature can be verified
361 by using the "-list-features" command, which should contain
362 "undefined-command-error-code".
364 ** The -trace-save MI command can optionally save trace buffer in Common
367 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
369 ** The command -data-list-register-values now accepts an optional
370 "--skip-unavailable" option. When used, only the available registers
373 ** The new command -trace-frame-collected dumps collected variables,
374 computed expressions, tvars, memory and registers in a traceframe.
376 ** The commands -stack-list-locals, -stack-list-arguments and
377 -stack-list-variables now accept an option "--skip-unavailable".
378 When used, only the available locals or arguments are displayed.
380 ** The -exec-run command now accepts an optional "--start" option.
381 When used, the command follows the same semantics as the "start"
382 command, stopping the program's execution at the start of its
383 main subprogram. Support for this feature can be verified using
384 the "-list-features" command, which should contain
385 "exec-run-start-option".
387 ** The new commands -catch-assert and -catch-exceptions insert
388 catchpoints stopping the program when Ada exceptions are raised.
390 ** The new command -info-ada-exceptions provides the equivalent of
391 the new "info exceptions" command.
393 * New system-wide configuration scripts
394 A GDB installation now provides scripts suitable for use as system-wide
395 configuration scripts for the following systems:
399 * GDB now supports target-assigned range stepping with remote targets.
400 This improves the performance of stepping source lines by reducing
401 the number of control packets from/to GDB. See "New remote packets"
404 * GDB now understands the element 'tvar' in the XML traceframe info.
405 It has the id of the collected trace state variables.
407 * On S/390 targets that provide the transactional-execution feature,
408 the program interruption transaction diagnostic block (TDB) is now
409 represented as a number of additional "registers" in GDB.
415 The vCont packet supports a new 'r' action, that tells the remote
416 stub to step through an address range itself, without GDB
417 involvemement at each single-step.
419 qXfer:libraries-svr4:read's annex
420 The previously unused annex of the qXfer:libraries-svr4:read packet
421 is now used to support passing an argument list. The remote stub
422 reports support for this argument list to GDB's qSupported query.
423 The defined arguments are "start" and "prev", used to reduce work
424 necessary for library list updating, resulting in significant
427 * New features in the GDB remote stub, GDBserver
429 ** GDBserver now supports target-assisted range stepping. Currently
430 enabled on x86/x86_64 GNU/Linux targets.
432 ** GDBserver now adds element 'tvar' in the XML in the reply to
433 'qXfer:traceframe-info:read'. It has the id of the collected
434 trace state variables.
436 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
439 * New 'z' formatter for printing and examining memory, this displays the
440 value as hexadecimal zero padded on the left to the size of the type.
442 * GDB can now use Windows x64 unwinding data.
444 * The "set remotebaud" command has been replaced by "set serial baud".
445 Similarly, "show remotebaud" has been replaced by "show serial baud".
446 The "set remotebaud" and "show remotebaud" commands are still available
447 to provide backward compatibility with older versions of GDB.
449 *** Changes in GDB 7.6
451 * Target record has been renamed to record-full.
452 Record/replay is now enabled with the "record full" command.
453 This also affects settings that are associated with full record/replay
454 that have been moved from "set/show record" to "set/show record full":
456 set|show record full insn-number-max
457 set|show record full stop-at-limit
458 set|show record full memory-query
460 * A new record target "record-btrace" has been added. The new target
461 uses hardware support to record the control-flow of a process. It
462 does not support replaying the execution, but it implements the
463 below new commands for investigating the recorded execution log.
464 This new recording method can be enabled using:
468 The "record-btrace" target is only available on Intel Atom processors
469 and requires a Linux kernel 2.6.32 or later.
471 * Two new commands have been added for record/replay to give information
472 about the recorded execution without having to replay the execution.
473 The commands are only supported by "record btrace".
475 record instruction-history prints the execution history at
476 instruction granularity
478 record function-call-history prints the execution history at
481 * New native configurations
483 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
484 FreeBSD/powerpc powerpc*-*-freebsd
485 x86_64/Cygwin x86_64-*-cygwin*
486 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
490 ARM AArch64 aarch64*-*-elf
491 ARM AArch64 GNU/Linux aarch64*-*-linux
492 Lynx 178 PowerPC powerpc-*-lynx*178
493 x86_64/Cygwin x86_64-*-cygwin*
494 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
496 * If the configured location of system.gdbinit file (as given by the
497 --with-system-gdbinit option at configure time) is in the
498 data-directory (as specified by --with-gdb-datadir at configure
499 time) or in one of its subdirectories, then GDB will look for the
500 system-wide init file in the directory specified by the
501 --data-directory command-line option.
503 * New command line options:
505 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
506 other initialization files, unlike -nx which disables all of them.
508 * Removed command line options
510 -epoch This was used by the gdb mode in Epoch, an ancient fork of
513 * The 'ptype' and 'whatis' commands now accept an argument to control
516 * 'info proc' now works on some core files.
520 ** Vectors can be created with gdb.Type.vector.
522 ** Python's atexit.register now works in GDB.
524 ** Types can be pretty-printed via a Python API.
526 ** Python 3 is now supported (in addition to Python 2.4 or later)
528 ** New class gdb.Architecture exposes GDB's internal representation
529 of architecture in the Python API.
531 ** New method Frame.architecture returns the gdb.Architecture object
532 corresponding to the frame's architecture.
534 * New Python-based convenience functions:
536 ** $_memeq(buf1, buf2, length)
537 ** $_streq(str1, str2)
539 ** $_regex(str, regex)
541 * The 'cd' command now defaults to using '~' (the home directory) if not
544 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
545 default for GCC since November 2000.
547 * The command 'forward-search' can now be abbreviated as 'fo'.
549 * The command 'info tracepoints' can now display 'installed on target'
550 or 'not installed on target' for each non-pending location of tracepoint.
552 * New configure options
554 --enable-libmcheck/--disable-libmcheck
555 By default, development versions are built with -lmcheck on hosts
556 that support it, in order to help track memory corruption issues.
557 Release versions, on the other hand, are built without -lmcheck
558 by default. The --enable-libmcheck/--disable-libmcheck configure
559 options allow the user to override that default.
560 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
561 This configure option allows the user to build GDB with
562 libbabeltrace using which GDB can read Common Trace Format data.
564 * New commands (for set/show, see "New options" below)
567 Catch signals. This is similar to "handle", but allows commands and
568 conditions to be attached.
571 List the BFDs known to GDB.
573 python-interactive [command]
575 Start a Python interactive prompt, or evaluate the optional command
576 and print the result of expressions.
579 "py" is a new alias for "python".
581 enable type-printer [name]...
582 disable type-printer [name]...
583 Enable or disable type printers.
587 ** For the Renesas Super-H architecture, the "regs" command has been removed
588 (has been deprecated in GDB 7.5), and "info all-registers" should be used
593 set print type methods (on|off)
594 show print type methods
595 Control whether method declarations are displayed by "ptype".
596 The default is to show them.
598 set print type typedefs (on|off)
599 show print type typedefs
600 Control whether typedef definitions are displayed by "ptype".
601 The default is to show them.
603 set filename-display basename|relative|absolute
604 show filename-display
605 Control the way in which filenames is displayed.
606 The default is "relative", which preserves previous behavior.
608 set trace-buffer-size
609 show trace-buffer-size
610 Request target to change the size of trace buffer.
612 set remote trace-buffer-size-packet auto|on|off
613 show remote trace-buffer-size-packet
614 Control the use of the remote protocol `QTBuffer:size' packet.
618 Control display of debugging messages related to ARM AArch64.
621 set debug coff-pe-read
622 show debug coff-pe-read
623 Control display of debugging messages related to reading of COFF/PE
628 Control display of debugging messages related to Mach-O symbols
631 set debug notification
632 show debug notification
633 Control display of debugging info for async remote notification.
637 ** Command parameter changes are now notified using new async record
638 "=cmd-param-changed".
639 ** Trace frame changes caused by command "tfind" are now notified using
640 new async record "=traceframe-changed".
641 ** The creation, deletion and modification of trace state variables
642 are now notified using new async records "=tsv-created",
643 "=tsv-deleted" and "=tsv-modified".
644 ** The start and stop of process record are now notified using new
645 async record "=record-started" and "=record-stopped".
646 ** Memory changes are now notified using new async record
648 ** The data-disassemble command response will include a "fullname" field
649 containing the absolute file name when source has been requested.
650 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
651 command, to allow pattern filling of memory areas.
652 ** New commands "-catch-load"/"-catch-unload" added for intercepting
653 library load/unload events.
654 ** The response to breakpoint commands and breakpoint async records
655 includes an "installed" field containing a boolean state about each
656 non-pending tracepoint location is whether installed on target or not.
657 ** Output of the "-trace-status" command includes a "trace-file" field
658 containing the name of the trace file being examined. This field is
659 optional, and only present when examining a trace file.
660 ** The "fullname" field is now always present along with the "file" field,
661 even if the file cannot be found by GDB.
663 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
664 You must have the LZMA library available when configuring GDB for this
665 feature to be enabled. For more information, see:
666 http://fedoraproject.org/wiki/Features/MiniDebugInfo
671 Set the size of trace buffer. The remote stub reports support for this
672 packet to gdb's qSupported query.
675 Enable Branch Trace Store (BTS)-based branch tracing for the current
676 thread. The remote stub reports support for this packet to gdb's
680 Disable branch tracing for the current thread. The remote stub reports
681 support for this packet to gdb's qSupported query.
684 Read the traced branches for the current thread. The remote stub
685 reports support for this packet to gdb's qSupported query.
687 *** Changes in GDB 7.5
689 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
690 for more x32 ABI info.
692 * GDB now supports access to MIPS DSP registers on Linux targets.
694 * GDB now supports debugging microMIPS binaries.
696 * The "info os" command on GNU/Linux can now display information on
697 several new classes of objects managed by the operating system:
698 "info os procgroups" lists process groups
699 "info os files" lists file descriptors
700 "info os sockets" lists internet-domain sockets
701 "info os shm" lists shared-memory regions
702 "info os semaphores" lists semaphores
703 "info os msg" lists message queues
704 "info os modules" lists loaded kernel modules
706 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
707 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
708 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
709 options and inspect the probe arguments using the new $_probe_arg family
710 of convenience variables. You can obtain more information about SystemTap
711 in <http://sourceware.org/systemtap/>.
713 * GDB now supports reversible debugging on ARM, it allows you to
714 debug basic ARM and THUMB instructions, and provides
715 record/replay support.
717 * The option "symbol-reloading" has been deleted as it is no longer used.
721 ** GDB commands implemented in Python can now be put in command class
724 ** The "maint set python print-stack on|off" is now deleted.
726 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
727 apply "flag enum"-style pretty-printing to any enum.
729 ** gdb.lookup_symbol can now work when there is no current frame.
731 ** gdb.Symbol now has a 'line' attribute, holding the line number in
732 the source at which the symbol was defined.
734 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
735 method 'value'. The former indicates whether the symbol needs a
736 frame in order to compute its value, and the latter computes the
739 ** A new method 'referenced_value' on gdb.Value objects which can
740 dereference pointer as well as C++ reference values.
742 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
743 which return the global and static blocks (as gdb.Block objects),
744 of the underlying symbol table, respectively.
746 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
747 object associated with a PC value.
749 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
750 of the address range occupied by code for the current source line.
752 * Go language support.
753 GDB now supports debugging programs written in the Go programming
756 * GDBserver now supports stdio connections.
757 E.g. (gdb) target remote | ssh myhost gdbserver - hello
759 * The binary "gdbtui" can no longer be built or installed.
760 Use "gdb -tui" instead.
762 * GDB will now print "flag" enums specially. A flag enum is one where
763 all the enumerator values have no bits in common when pairwise
764 "and"ed. When printing a value whose type is a flag enum, GDB will
765 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
766 (gdb) print (enum E) 3
769 * The filename part of a linespec will now match trailing components
770 of a source file name. For example, "break gcc/expr.c:1000" will
771 now set a breakpoint in build/gcc/expr.c, but not
774 * The "info proc" and "generate-core-file" commands will now also
775 work on remote targets connected to GDBserver on Linux.
777 * The command "info catch" has been removed. It has been disabled
780 * The "catch exception" and "catch assert" commands now accept
781 a condition at the end of the command, much like the "break"
782 command does. For instance:
784 (gdb) catch exception Constraint_Error if Barrier = True
786 Previously, it was possible to add a condition to such catchpoints,
787 but it had to be done as a second step, after the catchpoint had been
788 created, using the "condition" command.
790 * The "info static-tracepoint-marker" command will now also work on
791 native Linux targets with in-process agent.
793 * GDB can now set breakpoints on inlined functions.
795 * The .gdb_index section has been updated to include symbols for
796 inlined functions. GDB will ignore older .gdb_index sections by
797 default, which could cause symbol files to be loaded more slowly
798 until their .gdb_index sections can be recreated. The new command
799 "set use-deprecated-index-sections on" will cause GDB to use any older
800 .gdb_index sections it finds. This will restore performance, but the
801 ability to set breakpoints on inlined functions will be lost in symbol
802 files with older .gdb_index sections.
804 The .gdb_index section has also been updated to record more information
805 about each symbol. This speeds up the "info variables", "info functions"
806 and "info types" commands when used with programs having the .gdb_index
807 section, as well as speeding up debugging with shared libraries using
808 the .gdb_index section.
810 * Ada support for GDB/MI Variable Objects has been added.
812 * GDB can now support 'breakpoint always-inserted mode' in 'record'
817 ** New command -info-os is the MI equivalent of "info os".
819 ** Output logs ("set logging" and related) now include MI output.
823 ** "set use-deprecated-index-sections on|off"
824 "show use-deprecated-index-sections on|off"
825 Controls the use of deprecated .gdb_index sections.
827 ** "catch load" and "catch unload" can be used to stop when a shared
828 library is loaded or unloaded, respectively.
830 ** "enable count" can be used to auto-disable a breakpoint after
833 ** "info vtbl" can be used to show the virtual method tables for
834 C++ and Java objects.
836 ** "explore" and its sub commands "explore value" and "explore type"
837 can be used to recursively explore values and types of
838 expressions. These commands are available only if GDB is
839 configured with '--with-python'.
841 ** "info auto-load" shows status of all kinds of auto-loaded files,
842 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
843 sequences of commands files, "info auto-load python-scripts"
844 shows status of auto-loading Python script files,
845 "info auto-load local-gdbinit" shows status of loading init file
846 (.gdbinit) from current directory and "info auto-load libthread-db" shows
847 status of inferior specific thread debugging shared library loading.
849 ** "info auto-load-scripts", "set auto-load-scripts on|off"
850 and "show auto-load-scripts" commands have been deprecated, use their
851 "info auto-load python-scripts", "set auto-load python-scripts on|off"
852 and "show auto-load python-scripts" counterparts instead.
854 ** "dprintf location,format,args..." creates a dynamic printf, which
855 is basically a breakpoint that does a printf and immediately
856 resumes your program's execution, so it is like a printf that you
857 can insert dynamically at runtime instead of at compiletime.
859 ** "set print symbol"
861 Controls whether GDB attempts to display the symbol, if any,
862 corresponding to addresses it prints. This defaults to "on", but
863 you can set it to "off" to restore GDB's previous behavior.
865 * Deprecated commands
867 ** For the Renesas Super-H architecture, the "regs" command has been
868 deprecated, and "info all-registers" should be used instead.
872 Renesas RL78 rl78-*-elf
873 HP OpenVMS ia64 ia64-hp-openvms*
875 * GDBserver supports evaluation of breakpoint conditions. When
876 support is advertised by GDBserver, GDB may be told to send the
877 breakpoint conditions in bytecode form to GDBserver. GDBserver
878 will only report the breakpoint trigger to GDB when its condition
884 show mips compression
885 Select the compressed ISA encoding used in functions that have no symbol
886 information available. The encoding can be set to either of:
889 and is updated automatically from ELF file flags if available.
891 set breakpoint condition-evaluation
892 show breakpoint condition-evaluation
893 Control whether breakpoint conditions are evaluated by GDB ("host") or by
894 GDBserver ("target"). Default option "auto" chooses the most efficient
896 This option can improve debugger efficiency depending on the speed of the
900 Disable auto-loading globally.
903 Show auto-loading setting of all kinds of auto-loaded files.
905 set auto-load gdb-scripts on|off
906 show auto-load gdb-scripts
907 Control auto-loading of GDB canned sequences of commands files.
909 set auto-load python-scripts on|off
910 show auto-load python-scripts
911 Control auto-loading of Python script files.
913 set auto-load local-gdbinit on|off
914 show auto-load local-gdbinit
915 Control loading of init file (.gdbinit) from current directory.
917 set auto-load libthread-db on|off
918 show auto-load libthread-db
919 Control auto-loading of inferior specific thread debugging shared library.
921 set auto-load scripts-directory <dir1>[:<dir2>...]
922 show auto-load scripts-directory
923 Set a list of directories from which to load auto-loaded scripts.
924 Automatically loaded Python scripts and GDB scripts are located in one
925 of the directories listed by this option.
926 The delimiter (':' above) may differ according to the host platform.
928 set auto-load safe-path <dir1>[:<dir2>...]
929 show auto-load safe-path
930 Set a list of directories from which it is safe to auto-load files.
931 The delimiter (':' above) may differ according to the host platform.
933 set debug auto-load on|off
935 Control display of debugging info for auto-loading the files above.
937 set dprintf-style gdb|call|agent
939 Control the way in which a dynamic printf is performed; "gdb"
940 requests a GDB printf command, while "call" causes dprintf to call a
941 function in the inferior. "agent" requests that the target agent
942 (such as GDBserver) do the printing.
944 set dprintf-function <expr>
945 show dprintf-function
946 set dprintf-channel <expr>
948 Set the function and optional first argument to the call when using
949 the "call" style of dynamic printf.
951 set disconnected-dprintf on|off
952 show disconnected-dprintf
953 Control whether agent-style dynamic printfs continue to be in effect
954 after GDB disconnects.
956 * New configure options
959 Configure default value for the 'set auto-load scripts-directory'
960 setting above. It defaults to '$debugdir:$datadir/auto-load',
961 $debugdir representing global debugging info directories (available
962 via 'show debug-file-directory') and $datadir representing GDB's data
963 directory (available via 'show data-directory').
965 --with-auto-load-safe-path
966 Configure default value for the 'set auto-load safe-path' setting
967 above. It defaults to the --with-auto-load-dir setting.
969 --without-auto-load-safe-path
970 Set 'set auto-load safe-path' to '/', effectively disabling this
975 z0/z1 conditional breakpoints extension
977 The z0/z1 breakpoint insertion packets have been extended to carry
978 a list of conditional expressions over to the remote stub depending on the
979 condition evaluation mode. The use of this extension can be controlled
980 via the "set remote conditional-breakpoints-packet" command.
984 Specify the signals which the remote stub may pass to the debugged
985 program without GDB involvement.
987 * New command line options
989 --init-command=FILE, -ix Like --command, -x but execute it
990 before loading inferior.
991 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
992 execute it before loading inferior.
994 *** Changes in GDB 7.4
996 * GDB now handles ambiguous linespecs more consistently; the existing
997 FILE:LINE support has been expanded to other types of linespecs. A
998 breakpoint will now be set on all matching locations in all
999 inferiors, and locations will be added or removed according to
1002 * GDB now allows you to skip uninteresting functions and files when
1003 stepping with the "skip function" and "skip file" commands.
1005 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
1006 and "show remote hardware-watchpoint-length-limit". These allows to
1007 set or show the maximum length limit (in bytes) of a remote
1008 target hardware watchpoint.
1010 This allows e.g. to use "unlimited" hardware watchpoints with the
1011 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
1012 watchpoints are slower than real hardware watchpoints but are
1013 significantly faster than gdb software watchpoints.
1017 ** The register_pretty_printer function in module gdb.printing now takes
1018 an optional `replace' argument. If True, the new printer replaces any
1021 ** The "maint set python print-stack on|off" command has been
1022 deprecated and will be deleted in GDB 7.5.
1023 A new command: "set python print-stack none|full|message" has
1024 replaced it. Additionally, the default for "print-stack" is
1025 now "message", which just prints the error message without
1028 ** A prompt substitution hook (prompt_hook) is now available to the
1031 ** A new Python module, gdb.prompt has been added to the GDB Python
1032 modules library. This module provides functionality for
1033 escape sequences in prompts (used by set/show
1034 extended-prompt). These escape sequences are replaced by their
1035 corresponding value.
1037 ** Python commands and convenience-functions located in
1038 'data-directory'/python/gdb/command and
1039 'data-directory'/python/gdb/function are now automatically loaded
1042 ** Blocks now provide four new attributes. global_block and
1043 static_block will return the global and static blocks
1044 respectively. is_static and is_global are boolean attributes
1045 that indicate if the block is one of those two types.
1047 ** Symbols now provide the "type" attribute, the type of the symbol.
1049 ** The "gdb.breakpoint" function has been deprecated in favor of
1052 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
1053 of a function. This class is based on the "finish" command
1054 available in the CLI.
1056 ** Type objects for struct and union types now allow access to
1057 the fields using standard Python dictionary (mapping) methods.
1058 For example, "some_type['myfield']" now works, as does
1059 "some_type.items()".
1061 ** A new event "gdb.new_objfile" has been added, triggered by loading a
1064 ** A new function, "deep_items" has been added to the gdb.types
1065 module in the GDB Python modules library. This function returns
1066 an iterator over the fields of a struct or union type. Unlike
1067 the standard Python "iteritems" method, it will recursively traverse
1068 any anonymous fields.
1072 ** "*stopped" events can report several new "reason"s, such as
1075 ** Breakpoint changes are now notified using new async records, like
1076 "=breakpoint-modified".
1078 ** New command -ada-task-info.
1080 * libthread-db-search-path now supports two special values: $sdir and $pdir.
1081 $sdir specifies the default system locations of shared libraries.
1082 $pdir specifies the directory where the libpthread used by the application
1085 GDB no longer looks in $sdir and $pdir after it has searched the directories
1086 mentioned in libthread-db-search-path. If you want to search those
1087 directories, they must be specified in libthread-db-search-path.
1088 The default value of libthread-db-search-path on GNU/Linux and Solaris
1089 systems is now "$sdir:$pdir".
1091 $pdir is not supported by gdbserver, it is currently ignored.
1092 $sdir is supported by gdbserver.
1094 * New configure option --with-iconv-bin.
1095 When using the internationalization support like the one in the GNU C
1096 library, GDB will invoke the "iconv" program to get a list of supported
1097 character sets. If this program lives in a non-standard location, one can
1098 use this option to specify where to find it.
1100 * When natively debugging programs on PowerPC BookE processors running
1101 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
1102 watchpoints, which specify a mask in addition to an address to watch.
1103 The mask specifies that some bits of an address (the bits which are
1104 reset in the mask) should be ignored when matching the address accessed
1105 by the inferior against the watchpoint address. See the "PowerPC Embedded"
1106 section in the user manual for more details.
1108 * The new option --once causes GDBserver to stop listening for connections once
1109 the first connection is made. The listening port used by GDBserver will
1110 become available after that.
1112 * New commands "info macros" and "alias" have been added.
1114 * New function parameters suffix @entry specifies value of function parameter
1115 at the time the function got called. Entry values are available only since
1121 "!" is now an alias of the "shell" command.
1122 Note that no space is needed between "!" and SHELL COMMAND.
1126 watch EXPRESSION mask MASK_VALUE
1127 The watch command now supports the mask argument which allows creation
1128 of masked watchpoints, if the current architecture supports this feature.
1130 info auto-load-scripts [REGEXP]
1131 This command was formerly named "maintenance print section-scripts".
1132 It is now generally useful and is no longer a maintenance-only command.
1134 info macro [-all] [--] MACRO
1135 The info macro command has new options `-all' and `--'. The first for
1136 printing all definitions of a macro. The second for explicitly specifying
1137 the end of arguments and the beginning of the macro name in case the macro
1138 name starts with a hyphen.
1140 collect[/s] EXPRESSIONS
1141 The tracepoint collect command now takes an optional modifier "/s"
1142 that directs it to dereference pointer-to-character types and
1143 collect the bytes of memory up to a zero byte. The behavior is
1144 similar to what you see when you use the regular print command on a
1145 string. An optional integer following the "/s" sets a bound on the
1146 number of bytes that will be collected.
1149 The trace start command now interprets any supplied arguments as a
1150 note to be recorded with the trace run, with an effect similar to
1151 setting the variable trace-notes.
1154 The trace stop command now interprets any arguments as a note to be
1155 mentioned along with the tstatus report that the trace was stopped
1156 with a command. The effect is similar to setting the variable
1159 * Tracepoints can now be enabled and disabled at any time after a trace
1160 experiment has been started using the standard "enable" and "disable"
1161 commands. It is now possible to start a trace experiment with no enabled
1162 tracepoints; GDB will display a warning, but will allow the experiment to
1163 begin, assuming that tracepoints will be enabled as needed while the trace
1166 * Fast tracepoints on 32-bit x86-architectures can now be placed at
1167 locations with 4-byte instructions, when they were previously
1168 limited to locations with instructions of 5 bytes or longer.
1172 set debug dwarf2-read
1173 show debug dwarf2-read
1174 Turns on or off display of debugging messages related to reading
1175 DWARF debug info. The default is off.
1177 set debug symtab-create
1178 show debug symtab-create
1179 Turns on or off display of debugging messages related to symbol table
1180 creation. The default is off.
1183 show extended-prompt
1184 Set the GDB prompt, and allow escape sequences to be inserted to
1185 display miscellaneous information (see 'help set extended-prompt'
1186 for the list of sequences). This prompt (and any information
1187 accessed through the escape sequences) is updated every time the
1188 prompt is displayed.
1190 set print entry-values (both|compact|default|if-needed|no|only|preferred)
1191 show print entry-values
1192 Set printing of frame argument values at function entry. In some cases
1193 GDB can determine the value of function argument which was passed by the
1194 function caller, even if the value was modified inside the called function.
1196 set debug entry-values
1197 show debug entry-values
1198 Control display of debugging info for determining frame argument values at
1199 function entry and virtual tail call frames.
1201 set basenames-may-differ
1202 show basenames-may-differ
1203 Set whether a source file may have multiple base names.
1204 (A "base name" is the name of a file with the directory part removed.
1205 Example: The base name of "/home/user/hello.c" is "hello.c".)
1206 If set, GDB will canonicalize file names (e.g., expand symlinks)
1207 before comparing them. Canonicalization is an expensive operation,
1208 but it allows the same file be known by more than one base name.
1209 If not set (the default), all source files are assumed to have just
1210 one base name, and gdb will do file name comparisons more efficiently.
1216 Set a user name and notes for the current and any future trace runs.
1217 This is useful for long-running and/or disconnected traces, to
1218 inform others (or yourself) as to who is running the trace, supply
1219 contact information, or otherwise explain what is going on.
1221 set trace-stop-notes
1222 show trace-stop-notes
1223 Set a note attached to the trace run, that is displayed when the
1224 trace has been stopped by a tstop command. This is useful for
1225 instance as an explanation, if you are stopping a trace run that was
1226 started by someone else.
1228 * New remote packets
1232 Dynamically enable a tracepoint in a started trace experiment.
1236 Dynamically disable a tracepoint in a started trace experiment.
1240 Set the user and notes of the trace run.
1244 Query the current status of a tracepoint.
1248 Query the minimum length of instruction at which a fast tracepoint may
1251 * Dcache size (number of lines) and line-size are now runtime-configurable
1252 via "set dcache line" and "set dcache line-size" commands.
1256 Texas Instruments TMS320C6x tic6x-*-*
1260 Renesas RL78 rl78-*-elf
1262 *** Changes in GDB 7.3.1
1264 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1266 *** Changes in GDB 7.3
1268 * GDB has a new command: "thread find [REGEXP]".
1269 It finds the thread id whose name, target id, or thread extra info
1270 matches the given regular expression.
1272 * The "catch syscall" command now works on mips*-linux* targets.
1274 * The -data-disassemble MI command now supports modes 2 and 3 for
1275 dumping the instruction opcodes.
1277 * New command line options
1279 -data-directory DIR Specify DIR as the "data-directory".
1280 This is mostly for testing purposes.
1282 * The "maint set python auto-load on|off" command has been renamed to
1283 "set auto-load-scripts on|off".
1285 * GDB has a new command: "set directories".
1286 It is like the "dir" command except that it replaces the
1287 source path list instead of augmenting it.
1289 * GDB now understands thread names.
1291 On GNU/Linux, "info threads" will display the thread name as set by
1292 prctl or pthread_setname_np.
1294 There is also a new command, "thread name", which can be used to
1295 assign a name internally for GDB to display.
1298 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1299 has been integrated into GDB.
1303 ** The function gdb.Write now accepts an optional keyword 'stream'.
1304 This keyword, when provided, will direct the output to either
1305 stdout, stderr, or GDB's logging output.
1307 ** Parameters can now be be sub-classed in Python, and in particular
1308 you may implement the get_set_doc and get_show_doc functions.
1309 This improves how Parameter set/show documentation is processed
1310 and allows for more dynamic content.
1312 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1313 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1314 have an is_valid method.
1316 ** Breakpoints can now be sub-classed in Python, and in particular
1317 you may implement a 'stop' function that is executed each time
1318 the inferior reaches that breakpoint.
1320 ** New function gdb.lookup_global_symbol looks up a global symbol.
1322 ** GDB values in Python are now callable if the value represents a
1323 function. For example, if 'some_value' represents a function that
1324 takes two integer parameters and returns a value, you can call
1325 that function like so:
1327 result = some_value (10,20)
1329 ** Module gdb.types has been added.
1330 It contains a collection of utilities for working with gdb.Types objects:
1331 get_basic_type, has_field, make_enum_dict.
1333 ** Module gdb.printing has been added.
1334 It contains utilities for writing and registering pretty-printers.
1335 New classes: PrettyPrinter, SubPrettyPrinter,
1336 RegexpCollectionPrettyPrinter.
1337 New function: register_pretty_printer.
1339 ** New commands "info pretty-printers", "enable pretty-printer" and
1340 "disable pretty-printer" have been added.
1342 ** gdb.parameter("directories") is now available.
1344 ** New function gdb.newest_frame returns the newest frame in the
1347 ** The gdb.InferiorThread class has a new "name" attribute. This
1348 holds the thread's name.
1350 ** Python Support for Inferior events.
1351 Python scripts can add observers to be notified of events
1352 occurring in the process being debugged.
1353 The following events are currently supported:
1354 - gdb.events.cont Continue event.
1355 - gdb.events.exited Inferior exited event.
1356 - gdb.events.stop Signal received, and Breakpoint hit events.
1360 ** GDB now puts template parameters in scope when debugging in an
1361 instantiation. For example, if you have:
1363 template<int X> int func (void) { return X; }
1365 then if you step into func<5>, "print X" will show "5". This
1366 feature requires proper debuginfo support from the compiler; it
1367 was added to GCC 4.5.
1369 ** The motion commands "next", "finish", "until", and "advance" now
1370 work better when exceptions are thrown. In particular, GDB will
1371 no longer lose control of the inferior; instead, the GDB will
1372 stop the inferior at the point at which the exception is caught.
1373 This functionality requires a change in the exception handling
1374 code that was introduced in GCC 4.5.
1376 * GDB now follows GCC's rules on accessing volatile objects when
1377 reading or writing target state during expression evaluation.
1378 One notable difference to prior behavior is that "print x = 0"
1379 no longer generates a read of x; the value of the assignment is
1380 now always taken directly from the value being assigned.
1382 * GDB now has some support for using labels in the program's source in
1383 linespecs. For instance, you can use "advance label" to continue
1384 execution to a label.
1386 * GDB now has support for reading and writing a new .gdb_index
1387 section. This section holds a fast index of DWARF debugging
1388 information and can be used to greatly speed up GDB startup and
1389 operation. See the documentation for `save gdb-index' for details.
1391 * The "watch" command now accepts an optional "-location" argument.
1392 When used, this causes GDB to watch the memory referred to by the
1393 expression. Such a watchpoint is never deleted due to it going out
1396 * GDB now supports thread debugging of core dumps on GNU/Linux.
1398 GDB now activates thread debugging using the libthread_db library
1399 when debugging GNU/Linux core dumps, similarly to when debugging
1400 live processes. As a result, when debugging a core dump file, GDB
1401 is now able to display pthread_t ids of threads. For example, "info
1402 threads" shows the same output as when debugging the process when it
1403 was live. In earlier releases, you'd see something like this:
1406 * 1 LWP 6780 main () at main.c:10
1408 While now you see this:
1411 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1413 It is also now possible to inspect TLS variables when debugging core
1416 When debugging a core dump generated on a machine other than the one
1417 used to run GDB, you may need to point GDB at the correct
1418 libthread_db library with the "set libthread-db-search-path"
1419 command. See the user manual for more details on this command.
1421 * When natively debugging programs on PowerPC BookE processors running
1422 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1423 which stop execution of the inferior whenever it executes an instruction
1424 at any address within the specified range. See the "PowerPC Embedded"
1425 section in the user manual for more details.
1427 * New features in the GDB remote stub, GDBserver
1429 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1430 and i686 LynxOS (version 5.x).
1432 ** GDBserver is now supported on Blackfin Linux.
1434 * New native configurations
1436 ia64 HP-UX ia64-*-hpux*
1440 Analog Devices, Inc. Blackfin Processor bfin-*
1442 * Ada task switching is now supported on sparc-elf targets when
1443 debugging a program using the Ravenscar Profile. For more information,
1444 see the "Tasking Support when using the Ravenscar Profile" section
1445 in the GDB user manual.
1447 * Guile support was removed.
1449 * New features in the GNU simulator
1451 ** The --map-info flag lists all known core mappings.
1453 ** CFI flashes may be simulated via the "cfi" device.
1455 *** Changes in GDB 7.2
1457 * Shared library support for remote targets by default
1459 When GDB is configured for a generic, non-OS specific target, like
1460 for example, --target=arm-eabi or one of the many *-*-elf targets,
1461 GDB now queries remote stubs for loaded shared libraries using the
1462 `qXfer:libraries:read' packet. Previously, shared library support
1463 was always disabled for such configurations.
1467 ** Argument Dependent Lookup (ADL)
1469 In C++ ADL lookup directs function search to the namespaces of its
1470 arguments even if the namespace has not been imported.
1480 Here the compiler will search for `foo' in the namespace of 'b'
1481 and find A::foo. GDB now supports this. This construct is commonly
1482 used in the Standard Template Library for operators.
1484 ** Improved User Defined Operator Support
1486 In addition to member operators, GDB now supports lookup of operators
1487 defined in a namespace and imported with a `using' directive, operators
1488 defined in the global scope, operators imported implicitly from an
1489 anonymous namespace, and the ADL operators mentioned in the previous
1491 GDB now also supports proper overload resolution for all the previously
1492 mentioned flavors of operators.
1494 ** static const class members
1496 Printing of static const class members that are initialized in the
1497 class definition has been fixed.
1499 * Windows Thread Information Block access.
1501 On Windows targets, GDB now supports displaying the Windows Thread
1502 Information Block (TIB) structure. This structure is visible either
1503 by using the new command `info w32 thread-information-block' or, by
1504 dereferencing the new convenience variable named `$_tlb', a
1505 thread-specific pointer to the TIB. This feature is also supported
1506 when remote debugging using GDBserver.
1508 * Static tracepoints
1510 Static tracepoints are calls in the user program into a tracing
1511 library. One such library is a port of the LTTng kernel tracer to
1512 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1513 When debugging with GDBserver, GDB now supports combining the GDB
1514 tracepoint machinery with such libraries. For example: the user can
1515 use GDB to probe a static tracepoint marker (a call from the user
1516 program into the tracing library) with the new "strace" command (see
1517 "New commands" below). This creates a "static tracepoint" in the
1518 breakpoint list, that can be manipulated with the same feature set
1519 as fast and regular tracepoints. E.g., collect registers, local and
1520 global variables, collect trace state variables, and define
1521 tracepoint conditions. In addition, the user can collect extra
1522 static tracepoint marker specific data, by collecting the new
1523 $_sdata internal variable. When analyzing the trace buffer, you can
1524 inspect $_sdata like any other variable available to GDB. For more
1525 information, see the "Tracepoints" chapter in GDB user manual. New
1526 remote packets have been defined to support static tracepoints, see
1527 the "New remote packets" section below.
1529 * Better reconstruction of tracepoints after disconnected tracing
1531 GDB will attempt to download the original source form of tracepoint
1532 definitions when starting a trace run, and then will upload these
1533 upon reconnection to the target, resulting in a more accurate
1534 reconstruction of the tracepoints that are in use on the target.
1538 You can now exercise direct control over the ways that GDB can
1539 affect your program. For instance, you can disallow the setting of
1540 breakpoints, so that the program can run continuously (assuming
1541 non-stop mode). In addition, the "observer" variable is available
1542 to switch all of the different controls; in observer mode, GDB
1543 cannot affect the target's behavior at all, which is useful for
1544 tasks like diagnosing live systems in the field.
1546 * The new convenience variable $_thread holds the number of the
1549 * New remote packets
1553 Return the address of the Windows Thread Information Block of a given thread.
1557 In response to several of the tracepoint packets, the target may now
1558 also respond with a number of intermediate `qRelocInsn' request
1559 packets before the final result packet, to have GDB handle
1560 relocating an instruction to execute at a different address. This
1561 is particularly useful for stubs that support fast tracepoints. GDB
1562 reports support for this feature in the qSupported packet.
1566 List static tracepoint markers in the target program.
1570 List static tracepoint markers at a given address in the target
1573 qXfer:statictrace:read
1575 Read the static trace data collected (by a `collect $_sdata'
1576 tracepoint action). The remote stub reports support for this packet
1577 to gdb's qSupported query.
1581 Send the current settings of GDB's permission flags.
1585 Send part of the source (textual) form of a tracepoint definition,
1586 which includes location, conditional, and action list.
1588 * The source command now accepts a -s option to force searching for the
1589 script in the source search path even if the script name specifies
1592 * New features in the GDB remote stub, GDBserver
1594 - GDBserver now support tracepoints (including fast tracepoints, and
1595 static tracepoints). The feature is currently supported by the
1596 i386-linux and amd64-linux builds. See the "Tracepoints support
1597 in gdbserver" section in the manual for more information.
1599 GDBserver JIT compiles the tracepoint's conditional agent
1600 expression bytecode into native code whenever possible for low
1601 overhead dynamic tracepoints conditionals. For such tracepoints,
1602 an expression that examines program state is evaluated when the
1603 tracepoint is reached, in order to determine whether to capture
1604 trace data. If the condition is simple and false, processing the
1605 tracepoint finishes very quickly and no data is gathered.
1607 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1608 for static tracepoints support.
1610 - GDBserver now supports x86_64 Windows 64-bit debugging.
1612 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1613 it understands register description.
1615 * The --batch flag now disables pagination and queries.
1617 * X86 general purpose registers
1619 GDB now supports reading/writing byte, word and double-word x86
1620 general purpose registers directly. This means you can use, say,
1621 $ah or $ax to refer, respectively, to the byte register AH and
1622 16-bit word register AX that are actually portions of the 32-bit
1623 register EAX or 64-bit register RAX.
1625 * The `commands' command now accepts a range of breakpoints to modify.
1626 A plain `commands' following a command that creates multiple
1627 breakpoints affects all the breakpoints set by that command. This
1628 applies to breakpoints set by `rbreak', and also applies when a
1629 single `break' command creates multiple breakpoints (e.g.,
1630 breakpoints on overloaded c++ functions).
1632 * The `rbreak' command now accepts a filename specification as part of
1633 its argument, limiting the functions selected by the regex to those
1634 in the specified file.
1636 * Support for remote debugging Windows and SymbianOS shared libraries
1637 from Unix hosts has been improved. Non Windows GDB builds now can
1638 understand target reported file names that follow MS-DOS based file
1639 system semantics, such as file names that include drive letters and
1640 use the backslash character as directory separator. This makes it
1641 possible to transparently use the "set sysroot" and "set
1642 solib-search-path" on Unix hosts to point as host copies of the
1643 target's shared libraries. See the new command "set
1644 target-file-system-kind" described below, and the "Commands to
1645 specify files" section in the user manual for more information.
1649 eval template, expressions...
1650 Convert the values of one or more expressions under the control
1651 of the string template to a command line, and call it.
1653 set target-file-system-kind unix|dos-based|auto
1654 show target-file-system-kind
1655 Set or show the assumed file system kind for target reported file
1658 save breakpoints <filename>
1659 Save all current breakpoint definitions to a file suitable for use
1660 in a later debugging session. To read the saved breakpoint
1661 definitions, use the `source' command.
1663 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1666 info static-tracepoint-markers
1667 Display information about static tracepoint markers in the target.
1669 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1670 Define a static tracepoint by probing a marker at the given
1671 function, line, address, or marker ID.
1675 Enable and disable observer mode.
1677 set may-write-registers on|off
1678 set may-write-memory on|off
1679 set may-insert-breakpoints on|off
1680 set may-insert-tracepoints on|off
1681 set may-insert-fast-tracepoints on|off
1682 set may-interrupt on|off
1683 Set individual permissions for GDB effects on the target. Note that
1684 some of these settings can have undesirable or surprising
1685 consequences, particularly when changed in the middle of a session.
1686 For instance, disabling the writing of memory can prevent
1687 breakpoints from being inserted, cause single-stepping to fail, or
1688 even crash your program, if you disable after breakpoints have been
1689 inserted. However, GDB should not crash.
1691 set record memory-query on|off
1692 show record memory-query
1693 Control whether to stop the inferior if memory changes caused
1694 by an instruction cannot be recorded.
1699 The disassemble command now supports "start,+length" form of two arguments.
1703 ** GDB now provides a new directory location, called the python directory,
1704 where Python scripts written for GDB can be installed. The location
1705 of that directory is <data-directory>/python, where <data-directory>
1706 is the GDB data directory. For more details, see section `Scripting
1707 GDB using Python' in the manual.
1709 ** The GDB Python API now has access to breakpoints, symbols, symbol
1710 tables, program spaces, inferiors, threads and frame's code blocks.
1711 Additionally, GDB Parameters can now be created from the API, and
1712 manipulated via set/show in the CLI.
1714 ** New functions gdb.target_charset, gdb.target_wide_charset,
1715 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1717 ** New exception gdb.GdbError.
1719 ** Pretty-printers are now also looked up in the current program space.
1721 ** Pretty-printers can now be individually enabled and disabled.
1723 ** GDB now looks for names of Python scripts to auto-load in a
1724 special section named `.debug_gdb_scripts', in addition to looking
1725 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1727 * Tracepoint actions were unified with breakpoint commands. In particular,
1728 there are no longer differences in "info break" output for breakpoints and
1729 tracepoints and the "commands" command can be used for both tracepoints and
1730 regular breakpoints.
1734 ARM Symbian arm*-*-symbianelf*
1736 * D language support.
1737 GDB now supports debugging programs written in the D programming
1740 * GDB now supports the extended ptrace interface for PowerPC which is
1741 available since Linux kernel version 2.6.34. This automatically enables
1742 any hardware breakpoints and additional hardware watchpoints available in
1743 the processor. The old ptrace interface exposes just one hardware
1744 watchpoint and no hardware breakpoints.
1746 * GDB is now able to use the Data Value Compare (DVC) register available on
1747 embedded PowerPC processors to implement in hardware simple watchpoint
1748 conditions of the form:
1750 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1752 This works in native GDB running on Linux kernels with the extended ptrace
1753 interface mentioned above.
1755 *** Changes in GDB 7.1
1759 ** Namespace Support
1761 GDB now supports importing of namespaces in C++. This enables the
1762 user to inspect variables from imported namespaces. Support for
1763 namepace aliasing has also been added. So, if a namespace is
1764 aliased in the current scope (e.g. namepace C=A; ) the user can
1765 print variables using the alias (e.g. (gdb) print C::x).
1769 All known bugs relating to the printing of virtual base class were
1770 fixed. It is now possible to call overloaded static methods using a
1775 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1776 and reinterpret_cast<> are now handled by the C++ expression parser.
1780 Xilinx MicroBlaze microblaze-*-*
1785 Xilinx MicroBlaze microblaze
1788 * Multi-program debugging.
1790 GDB now has support for multi-program (a.k.a. multi-executable or
1791 multi-exec) debugging. This allows for debugging multiple inferiors
1792 simultaneously each running a different program under the same GDB
1793 session. See "Debugging Multiple Inferiors and Programs" in the
1794 manual for more information. This implied some user visible changes
1795 in the multi-inferior support. For example, "info inferiors" now
1796 lists inferiors that are not running yet or that have exited
1797 already. See also "New commands" and "New options" below.
1799 * New tracing features
1801 GDB's tracepoint facility now includes several new features:
1803 ** Trace state variables
1805 GDB tracepoints now include support for trace state variables, which
1806 are variables managed by the target agent during a tracing
1807 experiment. They are useful for tracepoints that trigger each
1808 other, so for instance one tracepoint can count hits in a variable,
1809 and then a second tracepoint has a condition that is true when the
1810 count reaches a particular value. Trace state variables share the
1811 $-syntax of GDB convenience variables, and can appear in both
1812 tracepoint actions and condition expressions. Use the "tvariable"
1813 command to create, and "info tvariables" to view; see "Trace State
1814 Variables" in the manual for more detail.
1818 GDB now includes an option for defining fast tracepoints, which
1819 targets may implement more efficiently, such as by installing a jump
1820 into the target agent rather than a trap instruction. The resulting
1821 speedup can be by two orders of magnitude or more, although the
1822 tradeoff is that some program locations on some target architectures
1823 might not allow fast tracepoint installation, for instance if the
1824 instruction to be replaced is shorter than the jump. To request a
1825 fast tracepoint, use the "ftrace" command, with syntax identical to
1826 the regular trace command.
1828 ** Disconnected tracing
1830 It is now possible to detach GDB from the target while it is running
1831 a trace experiment, then reconnect later to see how the experiment
1832 is going. In addition, a new variable disconnected-tracing lets you
1833 tell the target agent whether to continue running a trace if the
1834 connection is lost unexpectedly.
1838 GDB now has the ability to save the trace buffer into a file, and
1839 then use that file as a target, similarly to you can do with
1840 corefiles. You can select trace frames, print data that was
1841 collected in them, and use tstatus to display the state of the
1842 tracing run at the moment that it was saved. To create a trace
1843 file, use "tsave <filename>", and to use it, do "target tfile
1846 ** Circular trace buffer
1848 You can ask the target agent to handle the trace buffer as a
1849 circular buffer, discarding the oldest trace frames to make room for
1850 newer ones, by setting circular-trace-buffer to on. This feature may
1851 not be available for all target agents.
1856 The disassemble command, when invoked with two arguments, now requires
1857 the arguments to be comma-separated.
1860 The info variables command now displays variable definitions. Files
1861 which only declare a variable are not shown.
1864 The source command is now capable of sourcing Python scripts.
1865 This feature is dependent on the debugger being build with Python
1868 Related to this enhancement is also the introduction of a new command
1869 "set script-extension" (see below).
1871 * New commands (for set/show, see "New options" below)
1873 record save [<FILENAME>]
1874 Save a file (in core file format) containing the process record
1875 execution log for replay debugging at a later time.
1877 record restore <FILENAME>
1878 Restore the process record execution log that was saved at an
1879 earlier time, for replay debugging.
1881 add-inferior [-copies <N>] [-exec <FILENAME>]
1884 clone-inferior [-copies <N>] [ID]
1885 Make a new inferior ready to execute the same program another
1886 inferior has loaded.
1891 maint info program-spaces
1892 List the program spaces loaded into GDB.
1894 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1895 show remote interrupt-sequence
1896 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1897 as the sequence to the remote target in order to interrupt the execution.
1898 Ctrl-C is a default. Some system prefers BREAK which is high level of
1899 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1900 Magic SysRq g. It is BREAK signal and character 'g'.
1902 set remote interrupt-on-connect [on | off]
1903 show remote interrupt-on-connect
1904 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1905 remote target when gdb connects to it. This is needed when you debug
1908 set remotebreak [on | off]
1910 Deprecated. Use "set/show remote interrupt-sequence" instead.
1912 tvariable $NAME [ = EXP ]
1913 Create or modify a trace state variable.
1916 List trace state variables and their values.
1918 delete tvariable $NAME ...
1919 Delete one or more trace state variables.
1922 Evaluate the given expressions without collecting anything into the
1923 trace buffer. (Valid in tracepoint actions only.)
1925 ftrace FN / FILE:LINE / *ADDR
1926 Define a fast tracepoint at the given function, line, or address.
1928 * New expression syntax
1930 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1931 GDB now parses 0b101010 identically with 42.
1935 set follow-exec-mode new|same
1936 show follow-exec-mode
1937 Control whether GDB reuses the same inferior across an exec call or
1938 creates a new one. This is useful to be able to restart the old
1939 executable after the inferior having done an exec call.
1941 set default-collect EXPR, ...
1942 show default-collect
1943 Define a list of expressions to be collected at each tracepoint.
1944 This is a useful way to ensure essential items are not overlooked,
1945 such as registers or a critical global variable.
1947 set disconnected-tracing
1948 show disconnected-tracing
1949 If set to 1, the target is instructed to continue tracing if it
1950 loses its connection to GDB. If 0, the target is to stop tracing
1953 set circular-trace-buffer
1954 show circular-trace-buffer
1955 If set to on, the target is instructed to use a circular trace buffer
1956 and discard the oldest trace frames instead of stopping the trace due
1957 to a full trace buffer. If set to off, the trace stops when the buffer
1958 fills up. Some targets may not support this.
1960 set script-extension off|soft|strict
1961 show script-extension
1962 If set to "off", the debugger does not perform any script language
1963 recognition, and all sourced files are assumed to be GDB scripts.
1964 If set to "soft" (the default), files are sourced according to
1965 filename extension, falling back to GDB scripts if the first
1967 If set to "strict", files are sourced according to filename extension.
1969 set ada trust-PAD-over-XVS on|off
1970 show ada trust-PAD-over-XVS
1971 If off, activate a workaround against a bug in the debugging information
1972 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1973 the GCC sources for more information about the GNAT encoding and
1974 PAD types in particular). It is always safe to set this option to
1975 off, but this introduces a slight performance penalty. The default
1978 * Python API Improvements
1980 ** GDB provides the new class gdb.LazyString. This is useful in
1981 some pretty-printing cases. The new method gdb.Value.lazy_string
1982 provides a simple way to create objects of this type.
1984 ** The fields returned by gdb.Type.fields now have an
1985 `is_base_class' attribute.
1987 ** The new method gdb.Type.range returns the range of an array type.
1989 ** The new method gdb.parse_and_eval can be used to parse and
1990 evaluate an expression.
1992 * New remote packets
1995 Define a trace state variable.
1998 Get the current value of a trace state variable.
2001 Set desired tracing behavior upon disconnection.
2004 Set the trace buffer to be linear or circular.
2007 Get data about the tracepoints currently in use.
2011 Process record now works correctly with hardware watchpoints.
2013 Multiple bug fixes have been made to the mips-irix port, making it
2014 much more reliable. In particular:
2015 - Debugging threaded applications is now possible again. Previously,
2016 GDB would hang while starting the program, or while waiting for
2017 the program to stop at a breakpoint.
2018 - Attaching to a running process no longer hangs.
2019 - An error occurring while loading a core file has been fixed.
2020 - Changing the value of the PC register now works again. This fixes
2021 problems observed when using the "jump" command, or when calling
2022 a function from GDB, or even when assigning a new value to $pc.
2023 - With the "finish" and "return" commands, the return value for functions
2024 returning a small array is now correctly printed.
2025 - It is now possible to break on shared library code which gets executed
2026 during a shared library init phase (code executed while executing
2027 their .init section). Previously, the breakpoint would have no effect.
2028 - GDB is now able to backtrace through the signal handler for
2029 non-threaded programs.
2031 PIE (Position Independent Executable) programs debugging is now supported.
2032 This includes debugging execution of PIC (Position Independent Code) shared
2033 libraries although for that, it should be possible to run such libraries as an
2036 *** Changes in GDB 7.0
2038 * GDB now has an interface for JIT compilation. Applications that
2039 dynamically generate code can create symbol files in memory and register
2040 them with GDB. For users, the feature should work transparently, and
2041 for JIT developers, the interface is documented in the GDB manual in the
2042 "JIT Compilation Interface" chapter.
2044 * Tracepoints may now be conditional. The syntax is as for
2045 breakpoints; either an "if" clause appended to the "trace" command,
2046 or the "condition" command is available. GDB sends the condition to
2047 the target for evaluation using the same bytecode format as is used
2048 for tracepoint actions.
2050 * The disassemble command now supports: an optional /r modifier, print the
2051 raw instructions in hex as well as in symbolic form, and an optional /m
2052 modifier to print mixed source+assembly.
2054 * Process record and replay
2056 In a architecture environment that supports ``process record and
2057 replay'', ``process record and replay'' target can record a log of
2058 the process execution, and replay it with both forward and reverse
2061 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
2062 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
2063 set execution-direction {forward|reverse}, for targets that support
2066 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
2067 feature is available with a native GDB running on kernel version
2070 * GDB now has support for multi-byte and wide character sets on the
2071 target. Strings whose character type is wchar_t, char16_t, or
2072 char32_t are now correctly printed. GDB supports wide- and unicode-
2073 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
2074 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
2075 `printf'. This feature requires iconv to work properly; if your
2076 system does not have a working iconv, GDB can use GNU libiconv. See
2077 the installation instructions for more information.
2079 * GDB now supports automatic retrieval of shared library files from
2080 remote targets. To use this feature, specify a system root that begins
2081 with the `remote:' prefix, either via the `set sysroot' command or via
2082 the `--with-sysroot' configure-time option.
2084 * "info sharedlibrary" now takes an optional regex of libraries to show,
2085 and it now reports if a shared library has no debugging information.
2087 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
2088 now complete on file names.
2090 * When completing in expressions, gdb will attempt to limit
2091 completions to allowable structure or union fields, where appropriate.
2092 For instance, consider:
2094 # struct example { int f1; double f2; };
2095 # struct example variable;
2098 If the user types TAB at the end of this command line, the available
2099 completions will be "f1" and "f2".
2101 * Inlined functions are now supported. They show up in backtraces, and
2102 the "step", "next", and "finish" commands handle them automatically.
2104 * GDB now supports the token-splicing (##) and stringification (#)
2105 operators when expanding macros. It also supports variable-arity
2108 * GDB now supports inspecting extra signal information, exported by
2109 the new $_siginfo convenience variable. The feature is currently
2110 implemented on linux ARM, i386 and amd64.
2112 * GDB can now display the VFP floating point registers and NEON vector
2113 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
2114 can provide these registers (requires Linux 2.6.30 or later). Remote
2115 and simulator targets may also provide them.
2117 * New remote packets
2120 Search memory for a sequence of bytes.
2123 Turn off `+'/`-' protocol acknowledgments to permit more efficient
2124 operation over reliable transport links. Use of this packet is
2125 controlled by the `set remote noack-packet' command.
2128 Kill the process with the specified process ID. Use this in preference
2129 to `k' when multiprocess protocol extensions are supported.
2132 Obtains additional operating system information
2136 Read or write additional signal information.
2138 * Removed remote protocol undocumented extension
2140 An undocumented extension to the remote protocol's `S' stop reply
2141 packet that permited the stub to pass a process id was removed.
2142 Remote servers should use the `T' stop reply packet instead.
2144 * GDB now supports multiple function calling conventions according to the
2145 DWARF-2 DW_AT_calling_convention function attribute.
2147 * The SH target utilizes the aforementioned change to distinguish between gcc
2148 and Renesas calling convention. It also adds the new CLI commands
2149 `set/show sh calling-convention'.
2151 * GDB can now read compressed debug sections, as produced by GNU gold
2152 with the --compress-debug-sections=zlib flag.
2154 * 64-bit core files are now supported on AIX.
2156 * Thread switching is now supported on Tru64.
2158 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
2159 which will be allocated using malloc later in program execution.
2161 * The qXfer:libraries:read remote procotol packet now allows passing a
2162 list of section offsets.
2164 * On GNU/Linux, GDB can now attach to stopped processes. Several race
2165 conditions handling signals delivered during attach or thread creation
2166 have also been fixed.
2168 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
2169 From the user's standpoint, all unqualified instances of True and False
2170 are treated as the standard definitions, regardless of context.
2172 * GDB now parses C++ symbol and type names more flexibly. For
2175 template<typename T> class C { };
2178 GDB will now correctly handle all of:
2180 ptype C<char const *>
2181 ptype C<char const*>
2182 ptype C<const char *>
2183 ptype C<const char*>
2185 * New features in the GDB remote stub, gdbserver
2187 - The "--wrapper" command-line argument tells gdbserver to use a
2188 wrapper program to launch programs for debugging.
2190 - On PowerPC and S/390 targets, it is now possible to use a single
2191 gdbserver executable to debug both 32-bit and 64-bit programs.
2192 (This requires gdbserver itself to be built as a 64-bit executable.)
2194 - gdbserver uses the new noack protocol mode for TCP connections to
2195 reduce communications latency, if also supported and enabled in GDB.
2197 - Support for the sparc64-linux-gnu target is now included in
2200 - The amd64-linux build of gdbserver now supports debugging both
2201 32-bit and 64-bit programs.
2203 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
2204 now support hardware watchpoints, and will use them automatically
2209 GDB now has support for scripting using Python. Whether this is
2210 available is determined at configure time.
2212 New GDB commands can now be written in Python.
2214 * Ada tasking support
2216 Ada tasks can now be inspected in GDB. The following commands have
2220 Print the list of Ada tasks.
2222 Print detailed information about task number N.
2224 Print the task number of the current task.
2226 Switch the context of debugging to task number N.
2228 * Support for user-defined prefixed commands. The "define" command can
2229 add new commands to existing prefixes, e.g. "target".
2231 * Multi-inferior, multi-process debugging.
2233 GDB now has generalized support for multi-inferior debugging. See
2234 "Debugging Multiple Inferiors" in the manual for more information.
2235 Although availability still depends on target support, the command
2236 set is more uniform now. The GNU/Linux specific multi-forks support
2237 has been migrated to this new framework. This implied some user
2238 visible changes; see "New commands" and also "Removed commands"
2241 * Target descriptions can now describe the target OS ABI. See the
2242 "Target Description Format" section in the user manual for more
2245 * Target descriptions can now describe "compatible" architectures
2246 to indicate that the target can execute applications for a different
2247 architecture in addition to those for the main target architecture.
2248 See the "Target Description Format" section in the user manual for
2251 * Multi-architecture debugging.
2253 GDB now includes general supports for debugging applications on
2254 hybrid systems that use more than one single processor architecture
2255 at the same time. Each such hybrid architecture still requires
2256 specific support to be added. The only hybrid architecture supported
2257 in this version of GDB is the Cell Broadband Engine.
2259 * GDB now supports integrated debugging of Cell/B.E. applications that
2260 use both the PPU and SPU architectures. To enable support for hybrid
2261 Cell/B.E. debugging, you need to configure GDB to support both the
2262 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2263 --enable-targets configure option.
2265 * Non-stop mode debugging.
2267 For some targets, GDB now supports an optional mode of operation in
2268 which you can examine stopped threads while other threads continue
2269 to execute freely. This is referred to as non-stop mode, with the
2270 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2271 section in the user manual for more information.
2273 To be able to support remote non-stop debugging, a remote stub needs
2274 to implement the non-stop mode remote protocol extensions, as
2275 described in the "Remote Non-Stop" section of the user manual. The
2276 GDB remote stub, gdbserver, has been adjusted to support these
2277 extensions on linux targets.
2279 * New commands (for set/show, see "New options" below)
2281 catch syscall [NAME(S) | NUMBER(S)]
2282 Catch system calls. Arguments, which should be names of system
2283 calls or their numbers, mean catch only those syscalls. Without
2284 arguments, every syscall will be caught. When the inferior issues
2285 any of the specified syscalls, GDB will stop and announce the system
2286 call, both when it is called and when its call returns. This
2287 feature is currently available with a native GDB running on the
2288 Linux Kernel, under the following architectures: x86, x86_64,
2289 PowerPC and PowerPC64.
2291 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2293 Search memory for a sequence of bytes.
2295 maint set python print-stack
2296 maint show python print-stack
2297 Show a stack trace when an error is encountered in a Python script.
2300 Invoke CODE by passing it to the Python interpreter.
2305 These allow macros to be defined, undefined, and listed
2309 Show operating system information about processes.
2312 List the inferiors currently under GDB's control.
2315 Switch focus to inferior number NUM.
2318 Detach from inferior number NUM.
2321 Kill inferior number NUM.
2325 set spu stop-on-load
2326 show spu stop-on-load
2327 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2329 set spu auto-flush-cache
2330 show spu auto-flush-cache
2331 Control whether to automatically flush the software-managed cache
2332 during Cell/B.E. debugging.
2334 set sh calling-convention
2335 show sh calling-convention
2336 Control the calling convention used when calling SH target functions.
2339 show debug timestamp
2340 Control display of timestamps with GDB debugging output.
2342 set disassemble-next-line
2343 show disassemble-next-line
2344 Control display of disassembled source lines or instructions when
2347 set remote noack-packet
2348 show remote noack-packet
2349 Set/show the use of remote protocol QStartNoAckMode packet. See above
2350 under "New remote packets."
2352 set remote query-attached-packet
2353 show remote query-attached-packet
2354 Control use of remote protocol `qAttached' (query-attached) packet.
2356 set remote read-siginfo-object
2357 show remote read-siginfo-object
2358 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2361 set remote write-siginfo-object
2362 show remote write-siginfo-object
2363 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2366 set remote reverse-continue
2367 show remote reverse-continue
2368 Control use of remote protocol 'bc' (reverse-continue) packet.
2370 set remote reverse-step
2371 show remote reverse-step
2372 Control use of remote protocol 'bs' (reverse-step) packet.
2374 set displaced-stepping
2375 show displaced-stepping
2376 Control displaced stepping mode. Displaced stepping is a way to
2377 single-step over breakpoints without removing them from the debuggee.
2378 Also known as "out-of-line single-stepping".
2381 show debug displaced
2382 Control display of debugging info for displaced stepping.
2384 maint set internal-error
2385 maint show internal-error
2386 Control what GDB does when an internal error is detected.
2388 maint set internal-warning
2389 maint show internal-warning
2390 Control what GDB does when an internal warning is detected.
2395 Use a wrapper program to launch programs for debugging.
2397 set multiple-symbols (all|ask|cancel)
2398 show multiple-symbols
2399 The value of this variable can be changed to adjust the debugger behavior
2400 when an expression or a breakpoint location contains an ambiguous symbol
2401 name (an overloaded function name, for instance).
2403 set breakpoint always-inserted
2404 show breakpoint always-inserted
2405 Keep breakpoints always inserted in the target, as opposed to inserting
2406 them when resuming the target, and removing them when the target stops.
2407 This option can improve debugger performance on slow remote targets.
2409 set arm fallback-mode (arm|thumb|auto)
2410 show arm fallback-mode
2411 set arm force-mode (arm|thumb|auto)
2413 These commands control how ARM GDB determines whether instructions
2414 are ARM or Thumb. The default for both settings is auto, which uses
2415 the current CPSR value for instructions without symbols; previous
2416 versions of GDB behaved as if "set arm fallback-mode arm".
2418 set disable-randomization
2419 show disable-randomization
2420 Standalone programs run with the virtual address space randomization enabled
2421 by default on some platforms. This option keeps the addresses stable across
2422 multiple debugging sessions.
2426 Control whether other threads are stopped or not when some thread hits
2431 Requests that asynchronous execution is enabled in the target, if available.
2432 In this case, it's possible to resume target in the background, and interact
2433 with GDB while the target is running. "show target-async" displays the
2434 current state of asynchronous execution of the target.
2436 set target-wide-charset
2437 show target-wide-charset
2438 The target-wide-charset is the name of the character set that GDB
2439 uses when printing characters whose type is wchar_t.
2441 set tcp auto-retry (on|off)
2443 set tcp connect-timeout
2444 show tcp connect-timeout
2445 These commands allow GDB to retry failed TCP connections to a remote stub
2446 with a specified timeout period; this is useful if the stub is launched
2447 in parallel with GDB but may not be ready to accept connections immediately.
2449 set libthread-db-search-path
2450 show libthread-db-search-path
2451 Control list of directories which GDB will search for appropriate
2454 set schedule-multiple (on|off)
2455 show schedule-multiple
2456 Allow GDB to resume all threads of all processes or only threads of
2457 the current process.
2461 Use more aggressive caching for accesses to the stack. This improves
2462 performance of remote debugging (particularly backtraces) without
2463 affecting correctness.
2465 set interactive-mode (on|off|auto)
2466 show interactive-mode
2467 Control whether GDB runs in interactive mode (on) or not (off).
2468 When in interactive mode, GDB waits for the user to answer all
2469 queries. Otherwise, GDB does not wait and assumes the default
2470 answer. When set to auto (the default), GDB determines which
2471 mode to use based on the stdin settings.
2476 For program forks, this is replaced by the new more generic `info
2477 inferiors' command. To list checkpoints, you can still use the
2478 `info checkpoints' command, which was an alias for the `info forks'
2482 Replaced by the new `inferior' command. To switch between
2483 checkpoints, you can still use the `restart' command, which was an
2484 alias for the `fork' command.
2487 This is removed, since some targets don't have a notion of
2488 processes. To switch between processes, you can still use the
2489 `inferior' command using GDB's own inferior number.
2492 For program forks, this is replaced by the new more generic `kill
2493 inferior' command. To delete a checkpoint, you can still use the
2494 `delete checkpoint' command, which was an alias for the `delete
2498 For program forks, this is replaced by the new more generic `detach
2499 inferior' command. To detach a checkpoint, you can still use the
2500 `detach checkpoint' command, which was an alias for the `detach
2503 * New native configurations
2505 x86/x86_64 Darwin i[34567]86-*-darwin*
2507 x86_64 MinGW x86_64-*-mingw*
2511 Lattice Mico32 lm32-*
2512 x86 DICOS i[34567]86-*-dicos*
2513 x86_64 DICOS x86_64-*-dicos*
2516 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2517 (mingw32ce) debugging.
2523 These commands were actually not implemented on any target.
2525 *** Changes in GDB 6.8
2527 * New native configurations
2529 NetBSD/hppa hppa*-*netbsd*
2530 Xtensa GNU/Linux xtensa*-*-linux*
2534 NetBSD/hppa hppa*-*-netbsd*
2535 Xtensa GNU/Lunux xtensa*-*-linux*
2537 * Change in command line behavior -- corefiles vs. process ids.
2539 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2540 attaching to process NUMBER fails, GDB no longer attempts to open a
2541 core file named NUMBER. Attaching to a program using the -c option
2542 is no longer supported. Instead, use the '-p' or '--pid' options.
2544 * GDB can now be built as a native debugger for debugging Windows x86
2545 (mingw32) Portable Executable (PE) programs.
2547 * Pending breakpoints no longer change their number when their address
2550 * GDB now supports breakpoints with multiple locations,
2551 including breakpoints on C++ constructors, inside C++ templates,
2552 and in inlined functions.
2554 * GDB's ability to debug optimized code has been improved. GDB more
2555 accurately identifies function bodies and lexical blocks that occupy
2556 more than one contiguous range of addresses.
2558 * Target descriptions can now describe registers for PowerPC.
2560 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2561 registers on PowerPC targets.
2563 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2564 targets even when the libthread_db library is not available.
2566 * The GDB remote stub, gdbserver, now supports the new file transfer
2567 commands (remote put, remote get, and remote delete).
2569 * The GDB remote stub, gdbserver, now supports run and attach in
2570 extended-remote mode.
2572 * hppa*64*-*-hpux11* target broken
2573 The debugger is unable to start a program and fails with the following
2574 error: "Error trying to get information about dynamic linker".
2575 The gdb-6.7 release is also affected.
2577 * GDB now supports the --enable-targets= configure option to allow
2578 building a single GDB executable that supports multiple remote
2579 target architectures.
2581 * GDB now supports debugging C and C++ programs which use the
2582 Decimal Floating Point extension. In addition, the PowerPC target
2583 now has a set of pseudo-registers to inspect decimal float values
2584 stored in two consecutive float registers.
2586 * The -break-insert MI command can optionally create pending
2589 * Improved support for debugging Ada
2590 Many improvements to the Ada language support have been made. These
2592 - Better support for Ada2005 interface types
2593 - Improved handling of arrays and slices in general
2594 - Better support for Taft-amendment types
2595 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2597 - Improved command completion in Ada
2600 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2605 set print frame-arguments (all|scalars|none)
2606 show print frame-arguments
2607 The value of this variable can be changed to control which argument
2608 values should be printed by the debugger when displaying a frame.
2613 Transfer files to and from a remote target, and delete remote files.
2620 Transfer files to and from a remote target, and delete remote files.
2622 * New remote packets
2629 Open, close, read, write, and delete files on the remote system.
2632 Attach to an existing process on the remote system, in extended-remote
2636 Run a new process on the remote system, in extended-remote mode.
2638 *** Changes in GDB 6.7
2640 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2641 bfd, libiberty and opcodes, as revealed by static analysis donated by
2642 Coverity, Inc. (http://scan.coverity.com).
2644 * When looking up multiply-defined global symbols, GDB will now prefer the
2645 symbol definition in the current shared library if it was built using the
2646 -Bsymbolic linker option.
2648 * When the Text User Interface (TUI) is not configured, GDB will now
2649 recognize the -tui command-line option and print a message that the TUI
2652 * The GDB remote stub, gdbserver, now has lower overhead for high
2653 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2655 * GDB for MIPS targets now autodetects whether a remote target provides
2656 32-bit or 64-bit register values.
2658 * Support for C++ member pointers has been improved.
2660 * GDB now understands XML target descriptions, which specify the
2661 target's overall architecture. GDB can read a description from
2662 a local file or over the remote serial protocol.
2664 * Vectors of single-byte data use a new integer type which is not
2665 automatically displayed as character or string data.
2667 * The /s format now works with the print command. It displays
2668 arrays of single-byte integers and pointers to single-byte integers
2671 * Target descriptions can now describe target-specific registers,
2672 for architectures which have implemented the support (currently
2673 only ARM, M68K, and MIPS).
2675 * GDB and the GDB remote stub, gdbserver, now support the XScale
2678 * The GDB remote stub, gdbserver, has been updated to support
2679 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2680 has been rewritten to use the standard GDB remote protocol.
2682 * GDB can now step into C++ functions which are called through thunks.
2684 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2686 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2687 layout. It also supports a TextSeg= and DataSeg= response when only
2688 segment base addresses (rather than offsets) are available.
2690 * The /i format now outputs any trailing branch delay slot instructions
2691 immediately following the last instruction within the count specified.
2693 * The GDB remote protocol "T" stop reply packet now supports a
2694 "library" response. Combined with the new "qXfer:libraries:read"
2695 packet, this response allows GDB to debug shared libraries on targets
2696 where the operating system manages the list of loaded libraries (e.g.
2697 Windows and SymbianOS).
2699 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2700 (DLLs) on Windows and Windows CE targets.
2702 * GDB now supports a faster verification that a .debug file matches its binary
2703 according to its build-id signature, if the signature is present.
2709 Enable or disable hardware flow control (RTS/CTS) on the serial port
2710 when debugging using remote targets.
2712 set mem inaccessible-by-default
2713 show mem inaccessible-by-default
2714 If the target supplies a memory map, for instance via the remote
2715 protocol's "qXfer:memory-map:read" packet, setting this variable
2716 prevents GDB from accessing memory outside the memory map. This
2717 is useful for targets with memory mapped registers or which react
2718 badly to accesses of unmapped address space.
2720 set breakpoint auto-hw
2721 show breakpoint auto-hw
2722 If the target supplies a memory map, for instance via the remote
2723 protocol's "qXfer:memory-map:read" packet, setting this variable
2724 lets GDB use hardware breakpoints automatically for memory regions
2725 where it can not use software breakpoints. This covers both the
2726 "break" command and internal breakpoints used for other commands
2727 including "next" and "finish".
2730 catch exception unhandled
2731 Stop the program execution when Ada exceptions are raised.
2734 Stop the program execution when an Ada assertion failed.
2738 Set an alternate system root for target files. This is a more
2739 general version of "set solib-absolute-prefix", which is now
2740 an alias to "set sysroot".
2743 Provide extended SPU facility status information. This set of
2744 commands is available only when debugging the Cell/B.E. SPU
2747 * New native configurations
2749 OpenBSD/sh sh*-*openbsd*
2752 unset tdesc filename
2754 Use the specified local file as an XML target description, and do
2755 not query the target for its built-in description.
2759 OpenBSD/sh sh*-*-openbsd*
2760 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2761 Toshiba Media Processor mep-elf
2763 * New remote packets
2766 Ignore the specified signals; pass them directly to the debugged program
2767 without stopping other threads or reporting them to GDB.
2769 qXfer:features:read:
2770 Read an XML target description from the target, which describes its
2775 Read or write contents of an spufs file on the target system. These
2776 packets are available only on the Cell/B.E. SPU architecture.
2778 qXfer:libraries:read:
2779 Report the loaded shared libraries. Combined with new "T" packet
2780 response, this packet allows GDB to debug shared libraries on
2781 targets where the operating system manages the list of loaded
2782 libraries (e.g. Windows and SymbianOS).
2786 Support for these obsolete configurations has been removed.
2794 i[34567]86-*-lynxos*
2795 i[34567]86-*-netware*
2796 i[34567]86-*-sco3.2v5*
2797 i[34567]86-*-sco3.2v4*
2799 i[34567]86-*-sysv4.2*
2802 i[34567]86-*-unixware2*
2803 i[34567]86-*-unixware*
2812 * Other removed features
2819 Various m68k-only ROM monitors.
2826 Various Renesas ROM monitors and debugging interfaces for SH and
2831 Support for a Macraigor serial interface to on-chip debugging.
2832 GDB does not directly support the newer parallel or USB
2837 A debug information format. The predecessor to DWARF 2 and
2838 DWARF 3, which are still supported.
2840 Support for the HP aCC compiler on HP-UX/PA-RISC
2842 SOM-encapsulated symbolic debugging information, automatic
2843 invocation of pxdb, and the aCC custom C++ ABI. This does not
2844 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2845 with aCC can still be debugged on an assembly level.
2847 MIPS ".pdr" sections
2849 A MIPS-specific format used to describe stack frame layout
2850 in debugging information.
2854 GDB could work with an older version of Guile to debug
2855 the interpreter and Scheme programs running in it.
2857 set mips stack-arg-size
2858 set mips saved-gpreg-size
2860 Use "set mips abi" to control parameter passing for MIPS.
2862 *** Changes in GDB 6.6
2867 Cell Broadband Engine SPU spu-elf
2869 * GDB can now be configured as a cross-debugger targeting native Windows
2870 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2871 running on a Windows system over TCP/IP to debug Windows programs.
2873 * The GDB remote stub, gdbserver, has been updated to support Windows and
2874 Cygwin debugging. Both single-threaded and multi-threaded programs are
2877 * The "set trust-readonly-sections" command works again. This command was
2878 broken in GDB 6.3, 6.4, and 6.5.
2880 * The "load" command now supports writing to flash memory, if the remote
2881 stub provides the required support.
2883 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2884 longer requires symbolic debug information (e.g. DWARF-2).
2889 unset substitute-path
2890 show substitute-path
2891 Manage a list of substitution rules that GDB uses to rewrite the name
2892 of the directories where the sources are located. This can be useful
2893 for instance when the sources were moved to a different location
2894 between compilation and debugging.
2898 Print each CLI command as it is executed. Each command is prefixed with
2899 a number of `+' symbols representing the nesting depth.
2900 The source command now has a `-v' option to enable the same feature.
2904 The ARM Demon monitor support (RDP protocol, "target rdp").
2906 Kernel Object Display, an embedded debugging feature which only worked with
2907 an obsolete version of Cisco IOS.
2909 The 'set download-write-size' and 'show download-write-size' commands.
2911 * New remote packets
2914 Tell a stub about GDB client features, and request remote target features.
2915 The first feature implemented is PacketSize, which allows the target to
2916 specify the size of packets it can handle - to minimize the number of
2917 packets required and improve performance when connected to a remote
2921 Fetch an OS auxilliary vector from the remote stub. This packet is a
2922 more efficient replacement for qPart:auxv:read.
2924 qXfer:memory-map:read:
2925 Fetch a memory map from the remote stub, including information about
2926 RAM, ROM, and flash memory devices.
2931 Erase and program a flash memory device.
2933 * Removed remote packets
2936 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2937 used it, and only gdbserver implemented it.
2939 *** Changes in GDB 6.5
2943 Renesas M32C/M16C m32c-elf
2945 Morpho Technologies ms1 ms1-elf
2949 init-if-undefined Initialize a convenience variable, but
2950 only if it doesn't already have a value.
2952 The following commands are presently only implemented for native GNU/Linux:
2954 checkpoint Save a snapshot of the program state.
2956 restart <n> Return the program state to a
2957 previously saved state.
2959 info checkpoints List currently saved checkpoints.
2961 delete-checkpoint <n> Delete a previously saved checkpoint.
2963 set|show detach-on-fork Tell gdb whether to detach from a newly
2964 forked process, or to keep debugging it.
2966 info forks List forks of the user program that
2967 are available to be debugged.
2969 fork <n> Switch to debugging one of several
2970 forks of the user program that are
2971 available to be debugged.
2973 delete-fork <n> Delete a fork from the list of forks
2974 that are available to be debugged (and
2975 kill the forked process).
2977 detach-fork <n> Delete a fork from the list of forks
2978 that are available to be debugged (and
2979 allow the process to continue).
2983 Morpho Technologies ms2 ms1-elf
2985 * Improved Windows host support
2987 GDB now builds as a cross debugger hosted on i686-mingw32, including
2988 native console support, and remote communications using either
2989 network sockets or serial ports.
2991 * Improved Modula-2 language support
2993 GDB can now print most types in the Modula-2 syntax. This includes:
2994 basic types, set types, record types, enumerated types, range types,
2995 pointer types and ARRAY types. Procedure var parameters are correctly
2996 printed and hexadecimal addresses and character constants are also
2997 written in the Modula-2 syntax. Best results can be obtained by using
2998 GNU Modula-2 together with the -gdwarf-2 command line option.
3002 The ARM rdi-share module.
3004 The Netware NLM debug server.
3006 *** Changes in GDB 6.4
3008 * New native configurations
3010 OpenBSD/arm arm*-*-openbsd*
3011 OpenBSD/mips64 mips64-*-openbsd*
3015 Morpho Technologies ms1 ms1-elf
3017 * New command line options
3019 --batch-silent As for --batch, but totally silent.
3020 --return-child-result The debugger will exist with the same value
3021 the child (debugged) program exited with.
3022 --eval-command COMMAND, -ex COMMAND
3023 Execute a single GDB CLI command. This may be
3024 specified multiple times and in conjunction
3025 with the --command (-x) option.
3027 * Deprecated commands removed
3029 The following commands, that were deprecated in 2000, have been
3033 set|show arm disassembly-flavor set|show arm disassembler
3034 othernames set arm disassembler
3035 set|show remotedebug set|show debug remote
3036 set|show archdebug set|show debug arch
3037 set|show eventdebug set|show debug event
3040 * New BSD user-level threads support
3042 It is now possible to debug programs using the user-level threads
3043 library on OpenBSD and FreeBSD. Currently supported (target)
3046 FreeBSD/amd64 x86_64-*-freebsd*
3047 FreeBSD/i386 i386-*-freebsd*
3048 OpenBSD/i386 i386-*-openbsd*
3050 Note that the new kernel threads libraries introduced in FreeBSD 5.x
3051 are not yet supported.
3053 * New support for Matsushita MN10300 w/sim added
3054 (Work in progress). mn10300-elf.
3056 * REMOVED configurations and files
3058 VxWorks and the XDR protocol *-*-vxworks
3059 Motorola MCORE mcore-*-*
3060 National Semiconductor NS32000 ns32k-*-*
3062 * New "set print array-indexes" command
3064 After turning this setting "on", GDB prints the index of each element
3065 when displaying arrays. The default is "off" to preserve the previous
3068 * VAX floating point support
3070 GDB now supports the not-quite-ieee VAX F and D floating point formats.
3072 * User-defined command support
3074 In addition to using $arg0..$arg9 for argument passing, it is now possible
3075 to use $argc to determine now many arguments have been passed. See the
3076 section on user-defined commands in the user manual for more information.
3078 *** Changes in GDB 6.3:
3080 * New command line option
3082 GDB now accepts -l followed by a number to set the timeout for remote
3085 * GDB works with GCC -feliminate-dwarf2-dups
3087 GDB now supports a more compact representation of DWARF-2 debug
3088 information using DW_FORM_ref_addr references. These are produced
3089 by GCC with the option -feliminate-dwarf2-dups and also by some
3090 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
3091 to use -feliminate-dwarf2-dups.
3093 * Internationalization
3095 When supported by the host system, GDB will be built with
3096 internationalization (libintl). The task of marking up the sources is
3097 continued, we're looking forward to our first translation.
3101 Initial support for debugging programs compiled with the GNAT
3102 implementation of the Ada programming language has been integrated
3103 into GDB. In this release, support is limited to expression evaluation.
3105 * New native configurations
3107 GNU/Linux/m32r m32r-*-linux-gnu
3111 GDB's remote protocol now includes support for the 'p' packet. This
3112 packet is used to fetch individual registers from a remote inferior.
3114 * END-OF-LIFE registers[] compatibility module
3116 GDB's internal register infrastructure has been completely rewritten.
3117 The new infrastructure making possible the implementation of key new
3118 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
3121 GDB 6.3 will be the last release to include the the registers[]
3122 compatibility module that allowed out-of-date configurations to
3123 continue to work. This change directly impacts the following
3133 powerpc bdm protocol
3135 Unless there is activity to revive these configurations, they will be
3136 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
3138 * OBSOLETE configurations and files
3140 Configurations that have been declared obsolete in this release have
3141 been commented out. Unless there is activity to revive these
3142 configurations, the next release of GDB will have their sources
3143 permanently REMOVED.
3152 *** Changes in GDB 6.2.1:
3154 * MIPS `break main; run' gave an heuristic-fence-post warning
3156 When attempting to run even a simple program, a warning about
3157 heuristic-fence-post being hit would be reported. This problem has
3160 * MIPS IRIX 'long double' crashed GDB
3162 When examining a long double variable, GDB would get a segmentation
3163 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
3164 IRIX long double values).
3168 A bug in the VAX stack code was causing problems with the "next"
3169 command. This problem has been fixed.
3171 *** Changes in GDB 6.2:
3173 * Fix for ``many threads''
3175 On GNU/Linux systems that use the NPTL threads library, a program
3176 rapidly creating and deleting threads would confuse GDB leading to the
3179 ptrace: No such process.
3180 thread_db_get_info: cannot get thread info: generic error
3182 This problem has been fixed.
3184 * "-async" and "-noasync" options removed.
3186 Support for the broken "-noasync" option has been removed (it caused
3189 * New ``start'' command.
3191 This command runs the program until the begining of the main procedure.
3193 * New BSD Kernel Data Access Library (libkvm) interface
3195 Using ``target kvm'' it is now possible to debug kernel core dumps and
3196 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
3197 platforms. Currently supported (native-only) configurations are:
3199 FreeBSD/amd64 x86_64-*-freebsd*
3200 FreeBSD/i386 i?86-*-freebsd*
3201 NetBSD/i386 i?86-*-netbsd*
3202 NetBSD/m68k m68*-*-netbsd*
3203 NetBSD/sparc sparc-*-netbsd*
3204 OpenBSD/amd64 x86_64-*-openbsd*
3205 OpenBSD/i386 i?86-*-openbsd*
3206 OpenBSD/m68k m68*-openbsd*
3207 OpenBSD/sparc sparc-*-openbsd*
3209 * Signal trampoline code overhauled
3211 Many generic problems with GDB's signal handling code have been fixed.
3212 These include: backtraces through non-contiguous stacks; recognition
3213 of sa_sigaction signal trampolines; backtrace from a NULL pointer
3214 call; backtrace through a signal trampoline; step into and out of
3215 signal handlers; and single-stepping in the signal trampoline.
3217 Please note that kernel bugs are a limiting factor here. These
3218 features have been shown to work on an s390 GNU/Linux system that
3219 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
3221 * Cygwin support for DWARF 2 added.
3223 * New native configurations
3225 GNU/Linux/hppa hppa*-*-linux*
3226 OpenBSD/hppa hppa*-*-openbsd*
3227 OpenBSD/m68k m68*-*-openbsd*
3228 OpenBSD/m88k m88*-*-openbsd*
3229 OpenBSD/powerpc powerpc-*-openbsd*
3230 NetBSD/vax vax-*-netbsd*
3231 OpenBSD/vax vax-*-openbsd*
3233 * END-OF-LIFE frame compatibility module
3235 GDB's internal frame infrastructure has been completely rewritten.
3236 The new infrastructure making it possible to support key new features
3237 including DWARF 2 Call Frame Information. To aid in the task of
3238 migrating old configurations to this new infrastructure, a
3239 compatibility module, that allowed old configurations to continue to
3240 work, was also included.
3242 GDB 6.2 will be the last release to include this frame compatibility
3243 module. This change directly impacts the following configurations:
3253 Unless there is activity to revive these configurations, they will be
3254 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3256 * REMOVED configurations and files
3258 Sun 3, running SunOS 3 m68*-*-sunos3*
3259 Sun 3, running SunOS 4 m68*-*-sunos4*
3260 Sun 2, running SunOS 3 m68000-*-sunos3*
3261 Sun 2, running SunOS 4 m68000-*-sunos4*
3262 Motorola 680x0 running LynxOS m68*-*-lynxos*
3263 AT&T 3b1/Unix pc m68*-att-*
3264 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3265 decstation mips-dec-* mips-little-*
3266 riscos mips-*-riscos* mips-*-sysv*
3267 sonymips mips-sony-*
3268 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3270 *** Changes in GDB 6.1.1:
3272 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3274 The TUI (Text-mode User Interface) is now built as part of a default
3275 GDB configuration. It is enabled by either selecting the TUI with the
3276 command line option "-i=tui" or by running the separate "gdbtui"
3277 program. For more information on the TUI, see the manual "Debugging
3280 * Pending breakpoint support (also included in GDB 6.1)
3282 Support has been added to allow you to specify breakpoints in shared
3283 libraries that have not yet been loaded. If a breakpoint location
3284 cannot be found, and the "breakpoint pending" option is set to auto,
3285 GDB queries you if you wish to make the breakpoint pending on a future
3286 shared-library load. If and when GDB resolves the breakpoint symbol,
3287 the pending breakpoint is removed as one or more regular breakpoints
3290 Pending breakpoints are very useful for GCJ Java debugging.
3292 * Fixed ISO-C build problems
3294 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3295 non ISO-C code that stopped them being built using a more strict ISO-C
3296 compiler (e.g., IBM's C compiler).
3298 * Fixed build problem on IRIX 5
3300 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3301 wasn't able to compile compile on an IRIX 5 system.
3303 * Added execute permission to gdb/gdbserver/configure
3305 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3306 permission. This bug would cause configure to fail on a number of
3307 systems (Solaris, IRIX). Ref: server/519.
3309 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3311 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3312 has been updated to use constant array sizes.
3314 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3316 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3317 its generated DWARF Call Frame Info. This encoding was causing GDB to
3318 panic, that panic has been fixed. Ref: gdb/1628.
3320 * Fixed a problem when examining parameters in shared library code.
3322 When examining parameters in optimized shared library code generated
3323 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3324 not available''. GDB now correctly displays the variable's value.
3326 *** Changes in GDB 6.1:
3328 * Removed --with-mmalloc
3330 Support for the mmalloc memory manager has been removed, as it
3331 conflicted with the internal gdb byte cache.
3333 * Changes in AMD64 configurations
3335 The AMD64 target now includes the %cs and %ss registers. As a result
3336 the AMD64 remote protocol has changed; this affects the floating-point
3337 and SSE registers. If you rely on those registers for your debugging,
3338 you should upgrade gdbserver on the remote side.
3340 * Revised SPARC target
3342 The SPARC target has been completely revised, incorporating the
3343 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3344 support for LynxOS and SunOS 4 has been dropped. Calling functions
3345 from within GDB on operating systems with a non-executable stack
3346 (Solaris, OpenBSD) now works.
3350 GDB has a new C++ demangler which does a better job on the mangled
3351 names generated by current versions of g++. It also runs faster, so
3352 with this and other changes gdb should now start faster on large C++
3355 * DWARF 2 Location Expressions
3357 GDB support for location expressions has been extended to support function
3358 arguments and frame bases. Older versions of GDB could crash when they
3361 * C++ nested types and namespaces
3363 GDB's support for nested types and namespaces in C++ has been
3364 improved, especially if you use the DWARF 2 debugging format. (This
3365 is the default for recent versions of GCC on most platforms.)
3366 Specifically, if you have a class "Inner" defined within a class or
3367 namespace "Outer", then GDB realizes that the class's name is
3368 "Outer::Inner", not simply "Inner". This should greatly reduce the
3369 frequency of complaints about not finding RTTI symbols. In addition,
3370 if you are stopped at inside of a function defined within a namespace,
3371 GDB modifies its name lookup accordingly.
3373 * New native configurations
3375 NetBSD/amd64 x86_64-*-netbsd*
3376 OpenBSD/amd64 x86_64-*-openbsd*
3377 OpenBSD/alpha alpha*-*-openbsd*
3378 OpenBSD/sparc sparc-*-openbsd*
3379 OpenBSD/sparc64 sparc64-*-openbsd*
3381 * New debugging protocols
3383 M32R with SDI protocol m32r-*-elf*
3385 * "set prompt-escape-char" command deleted.
3387 The command "set prompt-escape-char" has been deleted. This command,
3388 and its very obscure effet on GDB's prompt, was never documented,
3389 tested, nor mentioned in the NEWS file.
3391 * OBSOLETE configurations and files
3393 Configurations that have been declared obsolete in this release have
3394 been commented out. Unless there is activity to revive these
3395 configurations, the next release of GDB will have their sources
3396 permanently REMOVED.
3398 Sun 3, running SunOS 3 m68*-*-sunos3*
3399 Sun 3, running SunOS 4 m68*-*-sunos4*
3400 Sun 2, running SunOS 3 m68000-*-sunos3*
3401 Sun 2, running SunOS 4 m68000-*-sunos4*
3402 Motorola 680x0 running LynxOS m68*-*-lynxos*
3403 AT&T 3b1/Unix pc m68*-att-*
3404 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3405 decstation mips-dec-* mips-little-*
3406 riscos mips-*-riscos* mips-*-sysv*
3407 sonymips mips-sony-*
3408 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3410 * REMOVED configurations and files
3412 SGI Irix-4.x mips-sgi-irix4 or iris4
3413 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3414 Z8000 simulator z8k-zilog-none or z8ksim
3415 Matsushita MN10200 w/simulator mn10200-*-*
3416 H8/500 simulator h8500-hitachi-hms or h8500hms
3417 HP/PA running BSD hppa*-*-bsd*
3418 HP/PA running OSF/1 hppa*-*-osf*
3419 HP/PA Pro target hppa*-*-pro*
3420 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3421 386BSD i[3456]86-*-bsd*
3422 Sequent family i[3456]86-sequent-sysv4*
3423 i[3456]86-sequent-sysv*
3424 i[3456]86-sequent-bsd*
3425 SPARC running LynxOS sparc-*-lynxos*
3426 SPARC running SunOS 4 sparc-*-sunos4*
3427 Tsqware Sparclet sparclet-*-*
3428 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3430 *** Changes in GDB 6.0:
3434 Support for debugging the Objective-C programming language has been
3435 integrated into GDB.
3437 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3439 DWARF 2's Call Frame Information makes available compiler generated
3440 information that more exactly describes the program's run-time stack.
3441 By using this information, GDB is able to provide more robust stack
3444 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3445 have been updated to use a new backtrace mechanism which includes
3446 DWARF 2 CFI support.
3450 GDB's remote protocol has been extended to include support for hosted
3451 file I/O (where the remote target uses GDB's file system). See GDB's
3452 remote protocol documentation for details.
3454 * All targets using the new architecture framework.
3456 All of GDB's targets have been updated to use the new internal
3457 architecture framework. The way is now open for future GDB releases
3458 to include cross-architecture native debugging support (i386 on amd64,
3461 * GNU/Linux's Thread Local Storage (TLS)
3463 GDB now includes support for for the GNU/Linux implementation of
3464 per-thread variables.
3466 * GNU/Linux's Native POSIX Thread Library (NPTL)
3468 GDB's thread code has been updated to work with either the new
3469 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3471 * Separate debug info.
3473 GDB, in conjunction with BINUTILS, now supports a mechanism for
3474 automatically loading debug information from a separate file. Instead
3475 of shipping full debug and non-debug versions of system libraries,
3476 system integrators can now instead ship just the stripped libraries
3477 and optional debug files.
3479 * DWARF 2 Location Expressions
3481 DWARF 2 Location Expressions allow the compiler to more completely
3482 describe the location of variables (even in optimized code) to the
3485 GDB now includes preliminary support for location expressions (support
3486 for DW_OP_piece is still missing).
3490 A number of long standing bugs that caused GDB to die while starting a
3491 Java application have been fixed. GDB's Java support is now
3492 considered "useable".
3494 * GNU/Linux support for fork, vfork, and exec.
3496 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3497 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3500 * GDB supports logging output to a file
3502 There are two new commands, "set logging" and "show logging", which can be
3503 used to capture GDB's output to a file.
3505 * The meaning of "detach" has changed for gdbserver
3507 The "detach" command will now resume the application, as documented. To
3508 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3511 * d10v, m68hc11 `regs' command deprecated
3513 The `info registers' command has been updated so that it displays the
3514 registers using a format identical to the old `regs' command.
3518 A new command, "maint set profile on/off", has been added. This command can
3519 be used to enable or disable profiling while running GDB, to profile a
3520 session or a set of commands. In addition there is a new configure switch,
3521 "--enable-profiling", which will cause GDB to be compiled with profiling
3522 data, for more informative profiling results.
3524 * Default MI syntax changed to "mi2".
3526 The default MI (machine interface) syntax, enabled by the command line
3527 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3528 "mi1", can be enabled by specifying the option "-i=mi1".
3530 Support for the original "mi0" syntax (included in GDB 5.0) has been
3533 Fix for gdb/192: removed extraneous space when displaying frame level.
3534 Fix for gdb/672: update changelist is now output in mi list format.
3535 Fix for gdb/702: a -var-assign that updates the value now shows up
3536 in a subsequent -var-update.
3538 * New native configurations.
3540 FreeBSD/amd64 x86_64-*-freebsd*
3542 * Multi-arched targets.
3544 HP/PA HPUX11 hppa*-*-hpux*
3545 Renesas M32R/D w/simulator m32r-*-elf*
3547 * OBSOLETE configurations and files
3549 Configurations that have been declared obsolete in this release have
3550 been commented out. Unless there is activity to revive these
3551 configurations, the next release of GDB will have their sources
3552 permanently REMOVED.
3554 Z8000 simulator z8k-zilog-none or z8ksim
3555 Matsushita MN10200 w/simulator mn10200-*-*
3556 H8/500 simulator h8500-hitachi-hms or h8500hms
3557 HP/PA running BSD hppa*-*-bsd*
3558 HP/PA running OSF/1 hppa*-*-osf*
3559 HP/PA Pro target hppa*-*-pro*
3560 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3561 Sequent family i[3456]86-sequent-sysv4*
3562 i[3456]86-sequent-sysv*
3563 i[3456]86-sequent-bsd*
3564 Tsqware Sparclet sparclet-*-*
3565 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3567 * REMOVED configurations and files
3570 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3571 IBM AIX PS/2 i[3456]86-*-aix
3572 i386 running Mach 3.0 i[3456]86-*-mach3*
3573 i386 running Mach i[3456]86-*-mach*
3574 i386 running OSF/1 i[3456]86-*osf1mk*
3575 HP/Apollo 68k Family m68*-apollo*-sysv*,
3577 m68*-hp-bsd*, m68*-hp-hpux*
3578 Argonaut Risc Chip (ARC) arc-*-*
3579 Mitsubishi D30V d30v-*-*
3580 Fujitsu FR30 fr30-*-elf*
3581 OS/9000 i[34]86-*-os9k
3582 I960 with MON960 i960-*-coff
3584 * MIPS $fp behavior changed
3586 The convenience variable $fp, for the MIPS, now consistently returns
3587 the address of the current frame's base. Previously, depending on the
3588 context, $fp could refer to either $sp or the current frame's base
3589 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3590 The GNU Source-Level Debugger''.
3592 *** Changes in GDB 5.3:
3594 * GNU/Linux shared library multi-threaded performance improved.
3596 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3597 `/proc', in preference to `ptrace' for memory reads. This may result
3598 in an improvement in the start-up time of multi-threaded, shared
3599 library applications when run under GDB. One GDB user writes: ``loads
3600 shared libs like mad''.
3602 * ``gdbserver'' now supports multi-threaded applications on some targets
3604 Support for debugging multi-threaded applications which use
3605 the GNU/Linux LinuxThreads package has been added for
3606 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3607 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3609 * GDB now supports C/C++ preprocessor macros.
3611 GDB now expands preprocessor macro invocations in C/C++ expressions,
3612 and provides various commands for showing macro definitions and how
3615 The new command `macro expand EXPRESSION' expands any macro
3616 invocations in expression, and shows the result.
3618 The new command `show macro MACRO-NAME' shows the definition of the
3619 macro named MACRO-NAME, and where it was defined.
3621 Most compilers don't include information about macros in the debugging
3622 information by default. In GCC 3.1, for example, you need to compile
3623 your program with the options `-gdwarf-2 -g3'. If the macro
3624 information is present in the executable, GDB will read it.
3626 * Multi-arched targets.
3628 DEC Alpha (partial) alpha*-*-*
3629 DEC VAX (partial) vax-*-*
3631 National Semiconductor NS32000 (partial) ns32k-*-*
3632 Motorola 68000 (partial) m68k-*-*
3633 Motorola MCORE mcore-*-*
3637 Fujitsu FRV architecture added by Red Hat frv*-*-*
3640 * New native configurations
3642 Alpha NetBSD alpha*-*-netbsd*
3643 SH NetBSD sh*-*-netbsdelf*
3644 MIPS NetBSD mips*-*-netbsd*
3645 UltraSPARC NetBSD sparc64-*-netbsd*
3647 * OBSOLETE configurations and files
3649 Configurations that have been declared obsolete in this release have
3650 been commented out. Unless there is activity to revive these
3651 configurations, the next release of GDB will have their sources
3652 permanently REMOVED.
3654 Mitsubishi D30V d30v-*-*
3655 OS/9000 i[34]86-*-os9k
3656 IBM AIX PS/2 i[3456]86-*-aix
3657 Fujitsu FR30 fr30-*-elf*
3658 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3659 Argonaut Risc Chip (ARC) arc-*-*
3660 i386 running Mach 3.0 i[3456]86-*-mach3*
3661 i386 running Mach i[3456]86-*-mach*
3662 i386 running OSF/1 i[3456]86-*osf1mk*
3663 HP/Apollo 68k Family m68*-apollo*-sysv*,
3665 m68*-hp-bsd*, m68*-hp-hpux*
3666 I960 with MON960 i960-*-coff
3668 * OBSOLETE languages
3670 CHILL, a Pascal like language used by telecommunications companies.
3672 * REMOVED configurations and files
3674 AMD 29k family via UDI a29k-amd-udi, udi29k
3675 A29K VxWorks a29k-*-vxworks
3676 AMD 29000 embedded, using EBMON a29k-none-none
3677 AMD 29000 embedded with COFF a29k-none-coff
3678 AMD 29000 embedded with a.out a29k-none-aout
3680 testsuite/gdb.hp/gdb.threads-hp/ directory
3682 * New command "set max-user-call-depth <nnn>"
3684 This command allows the user to limit the call depth of user-defined
3685 commands. The default is 1024.
3687 * Changes in FreeBSD/i386 native debugging.
3689 Support for the "generate-core-file" has been added.
3691 * New commands "dump", "append", and "restore".
3693 These commands allow data to be copied from target memory
3694 to a bfd-format or binary file (dump and append), and back
3695 from a file into memory (restore).
3697 * Improved "next/step" support on multi-processor Alpha Tru64.
3699 The previous single-step mechanism could cause unpredictable problems,
3700 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3701 of a software single-step mechanism prevents this.
3703 *** Changes in GDB 5.2.1:
3711 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3712 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3713 Fix, by Joel Brobecker imported from mainline.
3715 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3716 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3717 Fix, by Fred Fish, imported from mainline.
3719 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3720 Surprisingly enough, it works now.
3721 By Michal Ludvig, imported from mainline.
3723 i386 hardware watchpoint support:
3724 avoid misses on second run for some targets.
3725 By Pierre Muller, imported from mainline.
3727 *** Changes in GDB 5.2:
3729 * New command "set trust-readonly-sections on[off]".
3731 This command is a hint that tells gdb that read-only sections
3732 really are read-only (ie. that their contents will not change).
3733 In this mode, gdb will go to the object file rather than the
3734 target to read memory from read-only sections (such as ".text").
3735 This can be a significant performance improvement on some
3736 (notably embedded) targets.
3738 * New command "generate-core-file" (or "gcore").
3740 This new gdb command allows the user to drop a core file of the child
3741 process state at any time. So far it's been implemented only for
3742 GNU/Linux and Solaris, but should be relatively easily ported to other
3743 hosts. Argument is core file name (defaults to core.<pid>).
3745 * New command line option
3747 GDB now accepts --pid or -p followed by a process id.
3749 * Change in command line behavior -- corefiles vs. process ids.
3751 There is a subtle behavior in the way in which GDB handles
3752 command line arguments. The first non-flag argument is always
3753 a program to debug, but the second non-flag argument may either
3754 be a corefile or a process id. Previously, GDB would attempt to
3755 open the second argument as a corefile, and if that failed, would
3756 issue a superfluous error message and then attempt to attach it as
3757 a process. Now, if the second argument begins with a non-digit,
3758 it will be treated as a corefile. If it begins with a digit,
3759 GDB will attempt to attach it as a process, and if no such process
3760 is found, will then attempt to open it as a corefile.
3762 * Changes in ARM configurations.
3764 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3765 configuration is fully multi-arch.
3767 * New native configurations
3769 ARM NetBSD arm*-*-netbsd*
3770 x86 OpenBSD i[3456]86-*-openbsd*
3771 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3772 Sparc64 running FreeBSD sparc64-*-freebsd*
3776 Sanyo XStormy16 xstormy16-elf
3778 * OBSOLETE configurations and files
3780 Configurations that have been declared obsolete in this release have
3781 been commented out. Unless there is activity to revive these
3782 configurations, the next release of GDB will have their sources
3783 permanently REMOVED.
3785 AMD 29k family via UDI a29k-amd-udi, udi29k
3786 A29K VxWorks a29k-*-vxworks
3787 AMD 29000 embedded, using EBMON a29k-none-none
3788 AMD 29000 embedded with COFF a29k-none-coff
3789 AMD 29000 embedded with a.out a29k-none-aout
3791 testsuite/gdb.hp/gdb.threads-hp/ directory
3793 * REMOVED configurations and files
3795 TI TMS320C80 tic80-*-*
3797 PowerPC Solaris powerpcle-*-solaris*
3798 PowerPC Windows NT powerpcle-*-cygwin32
3799 PowerPC Netware powerpc-*-netware*
3800 Harris/CXUX m88k m88*-harris-cxux*
3801 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3802 ns32k-utek-sysv* ns32k-utek-*
3803 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3804 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3805 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3806 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3807 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3809 * Changes to command line processing
3811 The new `--args' feature can be used to specify command-line arguments
3812 for the inferior from gdb's command line.
3814 * Changes to key bindings
3816 There is a new `operate-and-get-next' function bound to `C-o'.
3818 *** Changes in GDB 5.1.1
3820 Fix compile problem on DJGPP.
3822 Fix a problem with floating-point registers on the i386 being
3825 Fix to stop GDB crashing on .debug_str debug info.
3827 Numerous documentation fixes.
3829 Numerous testsuite fixes.
3831 *** Changes in GDB 5.1:
3833 * New native configurations
3835 Alpha FreeBSD alpha*-*-freebsd*
3836 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3837 MIPS GNU/Linux mips*-*-linux*
3838 MIPS SGI Irix 6.x mips*-sgi-irix6*
3839 ia64 AIX ia64-*-aix*
3840 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3844 Motorola 68HC11 and 68HC12 m68hc11-elf
3846 UltraSparc running GNU/Linux sparc64-*-linux*
3848 * OBSOLETE configurations and files
3850 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3851 Harris/CXUX m88k m88*-harris-cxux*
3852 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3853 ns32k-utek-sysv* ns32k-utek-*
3854 TI TMS320C80 tic80-*-*
3856 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3857 PowerPC Solaris powerpcle-*-solaris*
3858 PowerPC Windows NT powerpcle-*-cygwin32
3859 PowerPC Netware powerpc-*-netware*
3860 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3861 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3862 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3863 Apple Macintosh (MPW) host N/A
3865 stuff.c (Program to stuff files into a specially prepared space in kdb)
3866 kdb-start.c (Main loop for the standalone kernel debugger)
3868 Configurations that have been declared obsolete in this release have
3869 been commented out. Unless there is activity to revive these
3870 configurations, the next release of GDB will have their sources
3871 permanently REMOVED.
3873 * REMOVED configurations and files
3875 Altos 3068 m68*-altos-*
3876 Convex c1-*-*, c2-*-*
3878 ARM RISCix arm-*-* (as host)
3882 * GDB has been converted to ISO C.
3884 GDB's source code has been converted to ISO C. In particular, the
3885 sources are fully protoized, and rely on standard headers being
3890 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3892 * The MI enabled by default.
3894 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3895 revised and enabled by default. Packages which use GDB as a debugging
3896 engine behind a UI or another front end are encouraged to switch to
3897 using the GDB/MI interface, instead of the old annotations interface
3898 which is now deprecated.
3900 * Support for debugging Pascal programs.
3902 GDB now includes support for debugging Pascal programs. The following
3903 main features are supported:
3905 - Pascal-specific data types such as sets;
3907 - automatic recognition of Pascal sources based on file-name
3910 - Pascal-style display of data types, variables, and functions;
3912 - a Pascal expression parser.
3914 However, some important features are not yet supported.
3916 - Pascal string operations are not supported at all;
3918 - there are some problems with boolean types;
3920 - Pascal type hexadecimal constants are not supported
3921 because they conflict with the internal variables format;
3923 - support for Pascal objects and classes is not full yet;
3925 - unlike Pascal, GDB is case-sensitive for symbol names.
3927 * Changes in completion.
3929 Commands such as `shell', `run' and `set args', which pass arguments
3930 to inferior programs, now complete on file names, similar to what
3931 users expect at the shell prompt.
3933 Commands which accept locations, such as `disassemble', `print',
3934 `breakpoint', `until', etc. now complete on filenames as well as
3935 program symbols. Thus, if you type "break foob TAB", and the source
3936 files linked into the programs include `foobar.c', that file name will
3937 be one of the candidates for completion. However, file names are not
3938 considered for completion after you typed a colon that delimits a file
3939 name from a name of a function in that file, as in "break foo.c:bar".
3941 `set demangle-style' completes on available demangling styles.
3943 * New platform-independent commands:
3945 It is now possible to define a post-hook for a command as well as a
3946 hook that runs before the command. For more details, see the
3947 documentation of `hookpost' in the GDB manual.
3949 * Changes in GNU/Linux native debugging.
3951 Support for debugging multi-threaded programs has been completely
3952 revised for all platforms except m68k and sparc. You can now debug as
3953 many threads as your system allows you to have.
3955 Attach/detach is supported for multi-threaded programs.
3957 Support for SSE registers was added for x86. This doesn't work for
3958 multi-threaded programs though.
3960 * Changes in MIPS configurations.
3962 Multi-arch support is enabled for all MIPS configurations.
3964 GDB can now be built as native debugger on SGI Irix 6.x systems for
3965 debugging n32 executables. (Debugging 64-bit executables is not yet
3968 * Unified support for hardware watchpoints in all x86 configurations.
3970 Most (if not all) native x86 configurations support hardware-assisted
3971 breakpoints and watchpoints in a unified manner. This support
3972 implements debug register sharing between watchpoints, which allows to
3973 put a virtually infinite number of watchpoints on the same address,
3974 and also supports watching regions up to 16 bytes with several debug
3977 The new maintenance command `maintenance show-debug-regs' toggles
3978 debugging print-outs in functions that insert, remove, and test
3979 watchpoints and hardware breakpoints.
3981 * Changes in the DJGPP native configuration.
3983 New command ``info dos sysinfo'' displays assorted information about
3984 the CPU, OS, memory, and DPMI server.
3986 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3987 display information about segment descriptors stored in GDT, LDT, and
3990 New commands ``info dos pde'' and ``info dos pte'' display entries
3991 from Page Directory and Page Tables (for now works with CWSDPMI only).
3992 New command ``info dos address-pte'' displays the Page Table entry for
3993 a given linear address.
3995 GDB can now pass command lines longer than 126 characters to the
3996 program being debugged (requires an update to the libdbg.a library
3997 which is part of the DJGPP development kit).
3999 DWARF2 debug info is now supported.
4001 It is now possible to `step' and `next' through calls to `longjmp'.
4003 * Changes in documentation.
4005 All GDB documentation was converted to GFDL, the GNU Free
4006 Documentation License.
4008 Tracepoints-related commands are now fully documented in the GDB
4011 TUI, the Text-mode User Interface, is now documented in the manual.
4013 Tracepoints-related commands are now fully documented in the GDB
4016 The "GDB Internals" manual now has an index. It also includes
4017 documentation of `ui_out' functions, GDB coding standards, x86
4018 hardware watchpoints, and memory region attributes.
4020 * GDB's version number moved to ``version.in''
4022 The Makefile variable VERSION has been replaced by the file
4023 ``version.in''. People creating GDB distributions should update the
4024 contents of this file.
4028 GUD support is now a standard part of the EMACS distribution.
4030 *** Changes in GDB 5.0:
4032 * Improved support for debugging FP programs on x86 targets
4034 Unified and much-improved support for debugging floating-point
4035 programs on all x86 targets. In particular, ``info float'' now
4036 displays the FP registers in the same format on all x86 targets, with
4037 greater level of detail.
4039 * Improvements and bugfixes in hardware-assisted watchpoints
4041 It is now possible to watch array elements, struct members, and
4042 bitfields with hardware-assisted watchpoints. Data-read watchpoints
4043 on x86 targets no longer erroneously trigger when the address is
4046 * Improvements in the native DJGPP version of GDB
4048 The distribution now includes all the scripts and auxiliary files
4049 necessary to build the native DJGPP version on MS-DOS/MS-Windows
4050 machines ``out of the box''.
4052 The DJGPP version can now debug programs that use signals. It is
4053 possible to catch signals that happened in the debuggee, deliver
4054 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
4055 would kill the program being debugged.) Programs that hook hardware
4056 interrupts (keyboard, timer, etc.) can also be debugged.
4058 It is now possible to debug DJGPP programs that redirect their
4059 standard handles or switch them to raw (as opposed to cooked) mode, or
4060 even close them. The command ``run < foo > bar'' works as expected,
4061 and ``info terminal'' reports useful information about the debuggee's
4062 terminal, including raw/cooked mode, redirection, etc.
4064 The DJGPP version now uses termios functions for console I/O, which
4065 enables debugging graphics programs. Interrupting GDB with Ctrl-C
4068 DOS-style file names with drive letters are now fully supported by
4071 It is now possible to debug DJGPP programs that switch their working
4072 directory. It is also possible to rerun the debuggee any number of
4073 times without restarting GDB; thus, you can use the same setup,
4074 breakpoints, etc. for many debugging sessions.
4076 * New native configurations
4078 ARM GNU/Linux arm*-*-linux*
4079 PowerPC GNU/Linux powerpc-*-linux*
4083 Motorola MCore mcore-*-*
4084 x86 VxWorks i[3456]86-*-vxworks*
4085 PowerPC VxWorks powerpc-*-vxworks*
4086 TI TMS320C80 tic80-*-*
4088 * OBSOLETE configurations
4090 Altos 3068 m68*-altos-*
4091 Convex c1-*-*, c2-*-*
4093 ARM RISCix arm-*-* (as host)
4096 Configurations that have been declared obsolete will be commented out,
4097 but the code will be left in place. If there is no activity to revive
4098 these configurations before the next release of GDB, the sources will
4099 be permanently REMOVED.
4101 * Gould support removed
4103 Support for the Gould PowerNode and NP1 has been removed.
4105 * New features for SVR4
4107 On SVR4 native platforms (such as Solaris), if you attach to a process
4108 without first loading a symbol file, GDB will now attempt to locate and
4109 load symbols from the running process's executable file.
4111 * Many C++ enhancements
4113 C++ support has been greatly improved. Overload resolution now works properly
4114 in almost all cases. RTTI support is on the way.
4116 * Remote targets can connect to a sub-program
4118 A popen(3) style serial-device has been added. This device starts a
4119 sub-process (such as a stand-alone simulator) and then communicates
4120 with that. The sub-program to run is specified using the syntax
4121 ``|<program> <args>'' vis:
4123 (gdb) set remotedebug 1
4124 (gdb) target extended-remote |mn10300-elf-sim program-args
4126 * MIPS 64 remote protocol
4128 A long standing bug in the mips64 remote protocol where by GDB
4129 expected certain 32 bit registers (ex SR) to be transfered as 32
4130 instead of 64 bits has been fixed.
4132 The command ``set remote-mips64-transfers-32bit-regs on'' has been
4133 added to provide backward compatibility with older versions of GDB.
4135 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
4137 The command ``set remotebinarydownload'' command has been replaced by
4138 ``set remote X-packet''. Other commands in ``set remote'' family
4139 include ``set remote P-packet''.
4141 * Breakpoint commands accept ranges.
4143 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
4144 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
4145 ``tracepoint passcount'' also accepts a range of tracepoints.
4147 * ``apropos'' command added.
4149 The ``apropos'' command searches through command names and
4150 documentation strings, printing out matches, making it much easier to
4151 try to find a command that does what you are looking for.
4155 A new machine oriented interface (MI) has been added to GDB. This
4156 interface is designed for debug environments running GDB as a separate
4157 process. This is part of the long term libGDB project. See the
4158 "GDB/MI" chapter of the GDB manual for further information. It can be
4159 enabled by configuring with:
4161 .../configure --enable-gdbmi
4163 *** Changes in GDB-4.18:
4165 * New native configurations
4167 HP-UX 10.20 hppa*-*-hpux10.20
4168 HP-UX 11.x hppa*-*-hpux11.0*
4169 M68K GNU/Linux m68*-*-linux*
4173 Fujitsu FR30 fr30-*-elf*
4174 Intel StrongARM strongarm-*-*
4175 Mitsubishi D30V d30v-*-*
4177 * OBSOLETE configurations
4179 Gould PowerNode, NP1 np1-*-*, pn-*-*
4181 Configurations that have been declared obsolete will be commented out,
4182 but the code will be left in place. If there is no activity to revive
4183 these configurations before the next release of GDB, the sources will
4184 be permanently REMOVED.
4188 As a compatibility experiment, GDB's source files buildsym.h and
4189 buildsym.c have been converted to pure standard C, no longer
4190 containing any K&R compatibility code. We believe that all systems in
4191 use today either come with a standard C compiler, or have a GCC port
4192 available. If this is not true, please report the affected
4193 configuration to bug-gdb@gnu.org immediately. See the README file for
4194 information about getting a standard C compiler if you don't have one
4199 GDB now uses readline 2.2.
4201 * set extension-language
4203 You can now control the mapping between filename extensions and source
4204 languages by using the `set extension-language' command. For instance,
4205 you can ask GDB to treat .c files as C++ by saying
4206 set extension-language .c c++
4207 The command `info extensions' lists all of the recognized extensions
4208 and their associated languages.
4210 * Setting processor type for PowerPC and RS/6000
4212 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
4213 you can use the `set processor' command to specify what variant of the
4214 PowerPC family you are debugging. The command
4218 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
4219 following PowerPC and RS6000 variants:
4221 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
4222 rs6000 IBM RS6000 ("POWER") architecture, user-level view
4224 403GC IBM PowerPC 403GC
4225 505 Motorola PowerPC 505
4226 860 Motorola PowerPC 860 or 850
4227 601 Motorola PowerPC 601
4228 602 Motorola PowerPC 602
4229 603 Motorola/IBM PowerPC 603 or 603e
4230 604 Motorola PowerPC 604 or 604e
4231 750 Motorola/IBM PowerPC 750 or 750
4233 At the moment, this command just tells GDB what to name the
4234 special-purpose processor registers. Since almost all the affected
4235 registers are inaccessible to user-level programs, this command is
4236 only useful for remote debugging in its present form.
4240 Thanks to a major code donation from Hewlett-Packard, GDB now has much
4241 more extensive support for HP-UX. Added features include shared
4242 library support, kernel threads and hardware watchpoints for 11.00,
4243 support for HP's ANSI C and C++ compilers, and a compatibility mode
4244 for xdb and dbx commands.
4248 HP's donation includes the new concept of catchpoints, which is a
4249 generalization of the old catch command. On HP-UX, it is now possible
4250 to catch exec, fork, and vfork, as well as library loading.
4252 This means that the existing catch command has changed; its first
4253 argument now specifies the type of catch to be set up. See the
4254 output of "help catch" for a list of catchpoint types.
4256 * Debugging across forks
4258 On HP-UX, you can choose which process to debug when a fork() happens
4263 HP has donated a curses-based terminal user interface (TUI). To get
4264 it, build with --enable-tui. Although this can be enabled for any
4265 configuration, at present it only works for native HP debugging.
4267 * GDB remote protocol additions
4269 A new protocol packet 'X' that writes binary data is now available.
4270 Default behavior is to try 'X', then drop back to 'M' if the stub
4271 fails to respond. The settable variable `remotebinarydownload'
4272 allows explicit control over the use of 'X'.
4274 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4275 full 64-bit address. The command
4277 set remoteaddresssize 32
4279 can be used to revert to the old behaviour. For existing remote stubs
4280 the change should not be noticed, as the additional address information
4283 In order to assist in debugging stubs, you may use the maintenance
4284 command `packet' to send any text string to the stub. For instance,
4286 maint packet heythere
4288 sends the packet "$heythere#<checksum>". Note that it is very easy to
4289 disrupt a debugging session by sending the wrong packet at the wrong
4292 The compare-sections command allows you to compare section data on the
4293 target to what is in the executable file without uploading or
4294 downloading, by comparing CRC checksums.
4296 * Tracing can collect general expressions
4298 You may now collect general expressions at tracepoints. This requires
4299 further additions to the target-side stub; see tracepoint.c and
4300 doc/agentexpr.texi for further details.
4302 * mask-address variable for Mips
4304 For Mips targets, you may control the zeroing of the upper 32 bits of
4305 a 64-bit address by entering `set mask-address on'. This is mainly
4306 of interest to users of embedded R4xxx and R5xxx processors.
4308 * Higher serial baud rates
4310 GDB's serial code now allows you to specify baud rates 57600, 115200,
4311 230400, and 460800 baud. (Note that your host system may not be able
4312 to achieve all of these rates.)
4316 The i960 configuration now includes an initial implementation of a
4317 builtin simulator, contributed by Jim Wilson.
4320 *** Changes in GDB-4.17:
4322 * New native configurations
4324 Alpha GNU/Linux alpha*-*-linux*
4325 Unixware 2.x i[3456]86-unixware2*
4326 Irix 6.x mips*-sgi-irix6*
4327 PowerPC GNU/Linux powerpc-*-linux*
4328 PowerPC Solaris powerpcle-*-solaris*
4329 Sparc GNU/Linux sparc-*-linux*
4330 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4334 Argonaut Risc Chip (ARC) arc-*-*
4335 Hitachi H8/300S h8300*-*-*
4336 Matsushita MN10200 w/simulator mn10200-*-*
4337 Matsushita MN10300 w/simulator mn10300-*-*
4338 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4339 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4340 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4341 Mitsubishi D10V w/simulator d10v-*-*
4342 Mitsubishi M32R/D w/simulator m32r-*-elf*
4343 Tsqware Sparclet sparclet-*-*
4344 NEC V850 w/simulator v850-*-*
4346 * New debugging protocols
4348 ARM with RDI protocol arm*-*-*
4349 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4350 DDB and LSI variants of PMON protocol mips*-*-*
4351 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4352 PowerPC with SDS protocol powerpc{,le}-*-eabi
4353 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4357 All configurations can now understand and use the DWARF 2 debugging
4358 format. The choice is automatic, if the symbol file contains DWARF 2
4363 GDB now includes basic Java language support. This support is
4364 only useful with Java compilers that produce native machine code.
4366 * solib-absolute-prefix and solib-search-path
4368 For SunOS and SVR4 shared libraries, you may now set the prefix for
4369 loading absolute shared library symbol files, and the search path for
4370 locating non-absolute shared library symbol files.
4372 * Live range splitting
4374 GDB can now effectively debug code for which GCC has performed live
4375 range splitting as part of its optimization. See gdb/doc/LRS for
4376 more details on the expected format of the stabs information.
4380 GDB's support for the GNU Hurd, including thread debugging, has been
4381 updated to work with current versions of the Hurd.
4385 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4386 instruction set. ARM GDB automatically detects when Thumb
4387 instructions are in use, and adjusts disassembly and backtracing
4392 GDB's MIPS target configurations now handle the MIP16 16-bit
4397 GDB now includes support for overlays; if an executable has been
4398 linked such that multiple sections are based at the same address, GDB
4399 will decide which section to use for symbolic info. You can choose to
4400 control the decision manually, using overlay commands, or implement
4401 additional target-side support and use "overlay load-target" to bring
4402 in the overlay mapping. Do "help overlay" for more detail.
4406 The command "info symbol <address>" displays information about
4407 the symbol at the specified address.
4411 The standard remote protocol now includes an extension that allows
4412 asynchronous collection and display of trace data. This requires
4413 extensive support in the target-side debugging stub. Tracing mode
4414 includes a new interaction mode in GDB and new commands: see the
4415 file tracepoint.c for more details.
4419 Configurations for embedded MIPS now include a simulator contributed
4420 by Cygnus Solutions. The simulator supports the instruction sets
4421 of most MIPS variants.
4425 Sparc configurations may now include the ERC32 simulator contributed
4426 by the European Space Agency. The simulator is not built into
4427 Sparc targets by default; configure with --enable-sim to include it.
4431 For target configurations that may include multiple variants of a
4432 basic architecture (such as MIPS and SH), you may now set the
4433 architecture explicitly. "set arch" sets, "info arch" lists
4434 the possible architectures.
4436 *** Changes in GDB-4.16:
4438 * New native configurations
4440 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4441 M68K NetBSD m68k-*-netbsd*
4442 PowerPC AIX 4.x powerpc-*-aix*
4443 PowerPC MacOS powerpc-*-macos*
4444 PowerPC Windows NT powerpcle-*-cygwin32
4445 RS/6000 AIX 4.x rs6000-*-aix4*
4449 ARM with RDP protocol arm-*-*
4450 I960 with MON960 i960-*-coff
4451 MIPS VxWorks mips*-*-vxworks*
4452 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4453 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4455 Matra Sparclet sparclet-*-*
4459 The powerpc-eabi configuration now includes the PSIM simulator,
4460 contributed by Andrew Cagney, with assistance from Mike Meissner.
4461 PSIM is a very elaborate model of the PowerPC, including not only
4462 basic instruction set execution, but also details of execution unit
4463 performance and I/O hardware. See sim/ppc/README for more details.
4467 GDB now works with Solaris 2.5.
4469 * Windows 95/NT native
4471 GDB will now work as a native debugger on Windows 95 and Windows NT.
4472 To build it from source, you must use the "gnu-win32" environment,
4473 which uses a DLL to emulate enough of Unix to run the GNU tools.
4474 Further information, binaries, and sources are available at
4475 ftp.cygnus.com, under pub/gnu-win32.
4477 * dont-repeat command
4479 If a user-defined command includes the command `dont-repeat', then the
4480 command will not be repeated if the user just types return. This is
4481 useful if the command is time-consuming to run, so that accidental
4482 extra keystrokes don't run the same command many times.
4484 * Send break instead of ^C
4486 The standard remote protocol now includes an option to send a break
4487 rather than a ^C to the target in order to interrupt it. By default,
4488 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4490 * Remote protocol timeout
4492 The standard remote protocol includes a new variable `remotetimeout'
4493 that allows you to set the number of seconds before GDB gives up trying
4494 to read from the target. The default value is 2.
4496 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4498 By default GDB will automatically keep track of objects as they are
4499 loaded and unloaded by the dynamic linker. By using the command `set
4500 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4501 when shared library events occur, thus allowing you to set breakpoints
4502 in shared libraries which are explicitly loaded by the inferior.
4504 Note this feature does not work on hpux8. On hpux9 you must link
4505 /usr/lib/end.o into your program. This feature should work
4506 automatically on hpux10.
4508 * Irix 5.x hardware watchpoint support
4510 Irix 5 configurations now support the use of hardware watchpoints.
4512 * Mips protocol "SYN garbage limit"
4514 When debugging a Mips target using the `target mips' protocol, you
4515 may set the number of characters that GDB will ignore by setting
4516 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4517 every character. The default value is 1050.
4519 * Recording and replaying remote debug sessions
4521 If you set `remotelogfile' to the name of a file, gdb will write to it
4522 a recording of a remote debug session. This recording may then be
4523 replayed back to gdb using "gdbreplay". See gdbserver/README for
4524 details. This is useful when you have a problem with GDB while doing
4525 remote debugging; you can make a recording of the session and send it
4526 to someone else, who can then recreate the problem.
4528 * Speedups for remote debugging
4530 GDB includes speedups for downloading and stepping MIPS systems using
4531 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4532 and more efficient S-record downloading.
4534 * Memory use reductions and statistics collection
4536 GDB now uses less memory and reports statistics about memory usage.
4537 Try the `maint print statistics' command, for example.
4539 *** Changes in GDB-4.15:
4541 * Psymtabs for XCOFF
4543 The symbol reader for AIX GDB now uses partial symbol tables. This
4544 can greatly improve startup time, especially for large executables.
4546 * Remote targets use caching
4548 Remote targets now use a data cache to speed up communication with the
4549 remote side. The data cache could lead to incorrect results because
4550 it doesn't know about volatile variables, thus making it impossible to
4551 debug targets which use memory mapped I/O devices. `set remotecache
4552 off' turns the the data cache off.
4554 * Remote targets may have threads
4556 The standard remote protocol now includes support for multiple threads
4557 in the target system, using new protocol commands 'H' and 'T'. See
4558 gdb/remote.c for details.
4562 If GDB is configured with `--enable-netrom', then it will include
4563 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4564 acts as though it is a bank of ROM on the target board, but you can
4565 write into it over the network. GDB's support consists only of
4566 support for fast loading into the emulated ROM; to debug, you must use
4567 another protocol, such as standard remote protocol. The usual
4568 sequence is something like
4570 target nrom <netrom-hostname>
4572 target remote <netrom-hostname>:1235
4576 GDB now includes support for the Apple Macintosh, as a host only. It
4577 may be run as either an MPW tool or as a standalone application, and
4578 it can debug through the serial port. All the usual GDB commands are
4579 available, but to the target command, you must supply "serial" as the
4580 device type instead of "/dev/ttyXX". See mpw-README in the main
4581 directory for more information on how to build. The MPW configuration
4582 scripts */mpw-config.in support only a few targets, and only the
4583 mips-idt-ecoff target has been tested.
4587 GDB configuration now uses autoconf. This is not user-visible,
4588 but does simplify configuration and building.
4592 GDB now supports hpux10.
4594 *** Changes in GDB-4.14:
4596 * New native configurations
4598 x86 FreeBSD i[345]86-*-freebsd
4599 x86 NetBSD i[345]86-*-netbsd
4600 NS32k NetBSD ns32k-*-netbsd
4601 Sparc NetBSD sparc-*-netbsd
4605 A29K VxWorks a29k-*-vxworks
4606 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4607 CPU32 EST-300 emulator m68*-*-est*
4608 PowerPC ELF powerpc-*-elf
4611 * Alpha OSF/1 support for procfs
4613 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4614 possible to attach to running processes. As the mounting of the /proc
4615 filesystem is optional on the Alpha, GDB automatically determines
4616 the availability of /proc during startup. This can lead to problems
4617 if /proc is unmounted after GDB has been started.
4619 * Arguments to user-defined commands
4621 User commands may accept up to 10 arguments separated by whitespace.
4622 Arguments are accessed within the user command via $arg0..$arg9. A
4625 print $arg0 + $arg1 + $arg2
4627 To execute the command use:
4630 Defines the command "adder" which prints the sum of its three arguments.
4631 Note the arguments are text substitutions, so they may reference variables,
4632 use complex expressions, or even perform inferior function calls.
4634 * New `if' and `while' commands
4636 This makes it possible to write more sophisticated user-defined
4637 commands. Both commands take a single argument, which is the
4638 expression to evaluate, and must be followed by the commands to
4639 execute, one per line, if the expression is nonzero, the list being
4640 terminated by the word `end'. The `if' command list may include an
4641 `else' word, which causes the following commands to be executed only
4642 if the expression is zero.
4644 * Fortran source language mode
4646 GDB now includes partial support for Fortran 77. It will recognize
4647 Fortran programs and can evaluate a subset of Fortran expressions, but
4648 variables and functions may not be handled correctly. GDB will work
4649 with G77, but does not yet know much about symbols emitted by other
4652 * Better HPUX support
4654 Most debugging facilities now work on dynamic executables for HPPAs
4655 running hpux9 or later. You can attach to running dynamically linked
4656 processes, but by default the dynamic libraries will be read-only, so
4657 for instance you won't be able to put breakpoints in them. To change
4658 that behavior do the following before running the program:
4664 This will cause the libraries to be mapped private and read-write.
4665 To revert to the normal behavior, do this:
4671 You cannot set breakpoints or examine data in the library until after
4672 the library is loaded if the function/data symbols do not have
4675 GDB can now also read debug symbols produced by the HP C compiler on
4676 HPPAs (sorry, no C++, Fortran or 68k support).
4678 * Target byte order now dynamically selectable
4680 You can choose which byte order to use with a target system, via the
4681 commands "set endian big" and "set endian little", and you can see the
4682 current setting by using "show endian". You can also give the command
4683 "set endian auto", in which case GDB will use the byte order
4684 associated with the executable. Currently, only embedded MIPS
4685 configurations support dynamic selection of target byte order.
4687 * New DOS host serial code
4689 This version uses DPMI interrupts to handle buffered I/O, so you
4690 no longer need to run asynctsr when debugging boards connected to
4693 *** Changes in GDB-4.13:
4695 * New "complete" command
4697 This lists all the possible completions for the rest of the line, if it
4698 were to be given as a command itself. This is intended for use by emacs.
4700 * Trailing space optional in prompt
4702 "set prompt" no longer adds a space for you after the prompt you set. This
4703 allows you to set a prompt which ends in a space or one that does not.
4705 * Breakpoint hit counts
4707 "info break" now displays a count of the number of times the breakpoint
4708 has been hit. This is especially useful in conjunction with "ignore"; you
4709 can ignore a large number of breakpoint hits, look at the breakpoint info
4710 to see how many times the breakpoint was hit, then run again, ignoring one
4711 less than that number, and this will get you quickly to the last hit of
4714 * Ability to stop printing at NULL character
4716 "set print null-stop" will cause GDB to stop printing the characters of
4717 an array when the first NULL is encountered. This is useful when large
4718 arrays actually contain only short strings.
4720 * Shared library breakpoints
4722 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4723 breakpoints in shared libraries before the executable is run.
4725 * Hardware watchpoints
4727 There is a new hardware breakpoint for the watch command for sparclite
4728 targets. See gdb/sparclite/hw_breakpoint.note.
4730 Hardware watchpoints are also now supported under GNU/Linux.
4734 Annotations have been added. These are for use with graphical interfaces,
4735 and are still experimental. Currently only gdba.el uses these.
4737 * Improved Irix 5 support
4739 GDB now works properly with Irix 5.2.
4741 * Improved HPPA support
4743 GDB now works properly with the latest GCC and GAS.
4745 * New native configurations
4747 Sequent PTX4 i[34]86-sequent-ptx4
4748 HPPA running OSF/1 hppa*-*-osf*
4749 Atari TT running SVR4 m68*-*-sysv4*
4750 RS/6000 LynxOS rs6000-*-lynxos*
4754 OS/9000 i[34]86-*-os9k
4755 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4758 * Hitachi SH7000 and E7000-PC ICE support
4760 There is now support for communicating with the Hitachi E7000-PC ICE.
4761 This is available automatically when GDB is configured for the SH.
4765 As usual, a variety of small fixes and improvements, both generic
4766 and configuration-specific. See the ChangeLog for more detail.
4768 *** Changes in GDB-4.12:
4770 * Irix 5 is now supported
4774 GDB-4.12 on the HPPA has a number of changes which make it unable
4775 to debug the output from the currently released versions of GCC and
4776 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4777 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4778 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4781 *** Changes in GDB-4.11:
4783 * User visible changes:
4787 The "set remotedebug" option is now consistent between the mips remote
4788 target, remote targets using the gdb-specific protocol, UDI (AMD's
4789 debug protocol for the 29k) and the 88k bug monitor. It is now an
4790 integer specifying a debug level (normally 0 or 1, but 2 means more
4791 debugging info for the mips target).
4793 * DEC Alpha native support
4795 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4796 debug info, but GDB works fairly well with the DEC compiler and should
4797 work with a future GCC release. See the README file for a few
4798 Alpha-specific notes.
4800 * Preliminary thread implementation
4802 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4804 * LynxOS native and target support for 386
4806 This release has been hosted on LynxOS 2.2, and also can be configured
4807 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4810 * Improvements in C++ mangling/demangling.
4812 This release has much better g++ debugging, specifically in name
4813 mangling/demangling, virtual function calls, print virtual table,
4814 call methods, ...etc.
4816 *** Changes in GDB-4.10:
4818 * User visible changes:
4820 Remote debugging using the GDB-specific (`target remote') protocol now
4821 supports the `load' command. This is only useful if you have some
4822 other way of getting the stub to the target system, and you can put it
4823 somewhere in memory where it won't get clobbered by the download.
4825 Filename completion now works.
4827 When run under emacs mode, the "info line" command now causes the
4828 arrow to point to the line specified. Also, "info line" prints
4829 addresses in symbolic form (as well as hex).
4831 All vxworks based targets now support a user settable option, called
4832 vxworks-timeout. This option represents the number of seconds gdb
4833 should wait for responses to rpc's. You might want to use this if
4834 your vxworks target is, perhaps, a slow software simulator or happens
4835 to be on the far side of a thin network line.
4839 This release contains support for using a DEC alpha as a GDB host for
4840 cross debugging. Native alpha debugging is not supported yet.
4843 *** Changes in GDB-4.9:
4847 This is the first GDB release which is accompanied by a matching testsuite.
4848 The testsuite requires installation of dejagnu, which should be available
4849 via ftp from most sites that carry GNU software.
4853 'Cfront' style demangling has had its name changed to 'ARM' style, to
4854 emphasize that it was written from the specifications in the C++ Annotated
4855 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4856 disclaimers, it still generated too much confusion with users attempting to
4857 use gdb with AT&T cfront.
4861 GDB now uses a standard remote interface to a simulator library.
4862 So far, the library contains simulators for the Zilog Z8001/2, the
4863 Hitachi H8/300, H8/500 and Super-H.
4865 * New targets supported
4867 H8/300 simulator h8300-hitachi-hms or h8300hms
4868 H8/500 simulator h8500-hitachi-hms or h8500hms
4869 SH simulator sh-hitachi-hms or sh
4870 Z8000 simulator z8k-zilog-none or z8ksim
4871 IDT MIPS board over serial line mips-idt-ecoff
4873 Cross-debugging to GO32 targets is supported. It requires a custom
4874 version of the i386-stub.c module which is integrated with the
4875 GO32 memory extender.
4877 * New remote protocols
4879 MIPS remote debugging protocol.
4881 * New source languages supported
4883 This version includes preliminary support for Chill, a Pascal like language
4884 used by telecommunications companies. Chill support is also being integrated
4885 into the GNU compiler, but we don't know when it will be publically available.
4888 *** Changes in GDB-4.8:
4890 * HP Precision Architecture supported
4892 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4893 version of this support was available as a set of patches from the
4894 University of Utah. GDB does not support debugging of programs
4895 compiled with the HP compiler, because HP will not document their file
4896 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4897 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4899 Many problems in the preliminary version have been fixed.
4901 * Faster and better demangling
4903 We have improved template demangling and fixed numerous bugs in the GNU style
4904 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4905 character types (wchar_t) are now supported. Demangling of each symbol is now
4906 only done once, and is cached when the symbol table for a file is read in.
4907 This results in a small increase in memory usage for C programs, a moderate
4908 increase in memory usage for C++ programs, and a fantastic speedup in
4911 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4912 from the specifications in the Annotated Reference Manual, which AT&T's
4913 compiler does not actually implement.
4915 * G++ multiple inheritance compiler problem
4917 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4918 inheritance lattices was reworked to properly discover ambiguities. We
4919 recently found an example which causes this new algorithm to fail in a
4920 very subtle way, producing bad debug information for those classes.
4921 The file 'gcc.patch' (in this directory) can be applied to gcc to
4922 circumvent the problem. A future GCC release will contain a complete
4925 The previous G++ debug info problem (mentioned below for the gdb-4.7
4926 release) is fixed in gcc version 2.3.2.
4928 * Improved configure script
4930 The `configure' script will now attempt to guess your system type if
4931 you don't supply a host system type. The old scheme of supplying a
4932 host system triplet is preferable over using this. All the magic is
4933 done in the new `config.guess' script. Examine it for details.
4935 We have also brought our configure script much more in line with the FSF's
4936 version. It now supports the --with-xxx options. In particular,
4937 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4938 The resulting GDB will not be able to read arbitrary object file formats --
4939 only the format ``expected'' to be used on the configured target system.
4940 We hope to make this the default in a future release.
4942 * Documentation improvements
4944 There's new internal documentation on how to modify GDB, and how to
4945 produce clean changes to the code. We implore people to read it
4946 before submitting changes.
4948 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4949 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4950 `info' files are also provided. To build `info' files from scratch,
4951 you will need the latest `makeinfo' release, which will be available in
4952 a future texinfo-X.Y release.
4954 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4955 We're not sure exactly which versions have this problem, but it has
4956 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4957 or better. If that isn't possible, there is a patch in
4958 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4959 around this problem.
4963 GDB now supports array constants that can be used in expressions typed in by
4964 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4965 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4968 The new directory `gdb/sparclite' contains a program that demonstrates
4969 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4971 * New native hosts supported
4973 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4974 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4976 * New targets supported
4978 AMD 29k family via UDI a29k-amd-udi or udi29k
4980 * New file formats supported
4982 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4983 HPUX core files, and SCO 3.2v2 core files.
4987 Attaching to processes now works again; thanks for the many bug reports.
4989 We have also stomped on a bunch of core dumps caused by
4990 printf_filtered("%s") problems.
4992 We eliminated a copyright problem on the rpc and ptrace header files
4993 for VxWorks, which was discovered at the last minute during the 4.7
4994 release. You should now be able to build a VxWorks GDB.
4996 You can now interrupt gdb while an attached process is running. This
4997 will cause the attached process to stop, and give control back to GDB.
4999 We fixed problems caused by using too many file descriptors
5000 for reading symbols from object files and libraries. This was
5001 especially a problem for programs that used many (~100) shared
5004 The `step' command now only enters a subroutine if there is line number
5005 information for the subroutine. Otherwise it acts like the `next'
5006 command. Previously, `step' would enter subroutines if there was
5007 any debugging information about the routine. This avoids problems
5008 when using `cc -g1' on MIPS machines.
5010 * Internal improvements
5012 GDB's internal interfaces have been improved to make it easier to support
5013 debugging of multiple languages in the future.
5015 GDB now uses a common structure for symbol information internally.
5016 Minimal symbols (derived from linkage symbols in object files), partial
5017 symbols (from a quick scan of debug information), and full symbols
5018 contain a common subset of information, making it easier to write
5019 shared code that handles any of them.
5021 * New command line options
5023 We now accept --silent as an alias for --quiet.
5027 The memory-mapped-malloc library is now licensed under the GNU Library
5028 General Public License.
5030 *** Changes in GDB-4.7:
5032 * Host/native/target split
5034 GDB has had some major internal surgery to untangle the support for
5035 hosts and remote targets. Now, when you configure GDB for a remote
5036 target, it will no longer load in all of the support for debugging
5037 local programs on the host. When fully completed and tested, this will
5038 ensure that arbitrary host/target combinations are possible.
5040 The primary conceptual shift is to separate the non-portable code in
5041 GDB into three categories. Host specific code is required any time GDB
5042 is compiled on that host, regardless of the target. Target specific
5043 code relates to the peculiarities of the target, but can be compiled on
5044 any host. Native specific code is everything else: it can only be
5045 built when the host and target are the same system. Child process
5046 handling and core file support are two common `native' examples.
5048 GDB's use of /proc for controlling Unix child processes is now cleaner.
5049 It has been split out into a single module under the `target_ops' vector,
5050 plus two native-dependent functions for each system that uses /proc.
5052 * New hosts supported
5054 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
5055 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5056 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
5058 * New targets supported
5060 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5061 68030 and CPU32 m68030-*-*, m68332-*-*
5063 * New native hosts supported
5065 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
5066 (386bsd is not well tested yet)
5067 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
5069 * New file formats supported
5071 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
5072 supports reading of `a.out.adobe' object files, which are an a.out
5073 format extended with minimal information about multiple sections.
5077 `show copying' is the same as the old `info copying'.
5078 `show warranty' is the same as `info warrantee'.
5079 These were renamed for consistency. The old commands continue to work.
5081 `info handle' is a new alias for `info signals'.
5083 You can now define pre-command hooks, which attach arbitrary command
5084 scripts to any command. The commands in the hook will be executed
5085 prior to the user's command. You can also create a hook which will be
5086 executed whenever the program stops. See gdb.texinfo.
5090 We now deal with Cfront style name mangling, and can even extract type
5091 info from mangled symbols. GDB can automatically figure out which
5092 symbol mangling style your C++ compiler uses.
5094 Calling of methods and virtual functions has been improved as well.
5098 The crash that occured when debugging Sun Ansi-C compiled binaries is
5099 fixed. This was due to mishandling of the extra N_SO stabs output
5102 We also finally got Ultrix 4.2 running in house, and fixed core file
5103 support, with help from a dozen people on the net.
5105 John M. Farrell discovered that the reason that single-stepping was so
5106 slow on all of the Mips based platforms (primarily SGI and DEC) was
5107 that we were trying to demangle and lookup a symbol used for internal
5108 purposes on every instruction that was being stepped through. Changing
5109 the name of that symbol so that it couldn't be mistaken for a C++
5110 mangled symbol sped things up a great deal.
5112 Rich Pixley sped up symbol lookups in general by getting much smarter
5113 about when C++ symbol mangling is necessary. This should make symbol
5114 completion (TAB on the command line) much faster. It's not as fast as
5115 we'd like, but it's significantly faster than gdb-4.6.
5119 A new user controllable variable 'call_scratch_address' can
5120 specify the location of a scratch area to be used when GDB
5121 calls a function in the target. This is necessary because the
5122 usual method of putting the scratch area on the stack does not work
5123 in systems that have separate instruction and data spaces.
5125 We integrated changes to support the 29k UDI (Universal Debugger
5126 Interface), but discovered at the last minute that we didn't have all
5127 of the appropriate copyright paperwork. We are working with AMD to
5128 resolve this, and hope to have it available soon.
5132 We have sped up the remote serial line protocol, especially for targets
5133 with lots of registers. It now supports a new `expedited status' ('T')
5134 message which can be used in place of the existing 'S' status message.
5135 This allows the remote stub to send only the registers that GDB
5136 needs to make a quick decision about single-stepping or conditional
5137 breakpoints, eliminating the need to fetch the entire register set for
5138 each instruction being stepped through.
5140 The GDB remote serial protocol now implements a write-through cache for
5141 registers, only re-reading the registers if the target has run.
5143 There is also a new remote serial stub for SPARC processors. You can
5144 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
5145 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
5146 processor with a serial port.
5150 Configure.in files have become much easier to read and modify. A new
5151 `table driven' format makes it more obvious what configurations are
5152 supported, and what files each one uses.
5156 There is a new opcodes library which will eventually contain all of the
5157 disassembly routines and opcode tables. At present, it only contains
5158 Sparc and Z8000 routines. This will allow the assembler, debugger, and
5159 disassembler (binutils/objdump) to share these routines.
5161 The libiberty library is now copylefted under the GNU Library General
5162 Public License. This allows more liberal use, and was done so libg++
5163 can use it. This makes no difference to GDB, since the Library License
5164 grants all the rights from the General Public License.
5168 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
5169 reference to the stabs symbol info used by the debugger. It is (as far
5170 as we know) the only published document on this fascinating topic. We
5171 encourage you to read it, compare it to the stabs information on your
5172 system, and send improvements on the document in general (to
5173 bug-gdb@prep.ai.mit.edu).
5175 And, of course, many bugs have been fixed.
5178 *** Changes in GDB-4.6:
5180 * Better support for C++ function names
5182 GDB now accepts as input the "demangled form" of C++ overloaded function
5183 names and member function names, and can do command completion on such names
5184 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
5185 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
5186 Make use of command completion, it is your friend.
5188 GDB also now accepts a variety of C++ mangled symbol formats. They are
5189 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
5190 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
5191 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
5192 for the list of formats.
5194 * G++ symbol mangling problem
5196 Recent versions of gcc have a bug in how they emit debugging information for
5197 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
5198 directory) can be applied to gcc to fix the problem. Alternatively, if you
5199 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
5200 usual symptom is difficulty with setting breakpoints on methods. GDB complains
5201 about the method being non-existent. (We believe that version 2.2.2 of GCC has
5204 * New 'maintenance' command
5206 All of the commands related to hacking GDB internals have been moved out of
5207 the main command set, and now live behind the 'maintenance' command. This
5208 can also be abbreviated as 'mt'. The following changes were made:
5210 dump-me -> maintenance dump-me
5211 info all-breakpoints -> maintenance info breakpoints
5212 printmsyms -> maintenance print msyms
5213 printobjfiles -> maintenance print objfiles
5214 printpsyms -> maintenance print psymbols
5215 printsyms -> maintenance print symbols
5217 The following commands are new:
5219 maintenance demangle Call internal GDB demangler routine to
5220 demangle a C++ link name and prints the result.
5221 maintenance print type Print a type chain for a given symbol
5223 * Change to .gdbinit file processing
5225 We now read the $HOME/.gdbinit file before processing the argv arguments
5226 (e.g. reading symbol files or core files). This allows global parameters to
5227 be set, which will apply during the symbol reading. The ./.gdbinit is still
5228 read after argv processing.
5230 * New hosts supported
5232 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
5234 GNU/Linux support i386-unknown-linux or linux
5236 We are also including code to support the HP/PA running BSD and HPUX. This
5237 is almost guaranteed not to work, as we didn't have time to test or build it
5238 for this release. We are including it so that the more adventurous (or
5239 masochistic) of you can play with it. We also had major problems with the
5240 fact that the compiler that we got from HP doesn't support the -g option.
5243 * New targets supported
5245 Hitachi H8/300 h8300-hitachi-hms or h8300hms
5247 * More smarts about finding #include files
5249 GDB now remembers the compilation directory for all include files, and for
5250 all files from which C is generated (like yacc and lex sources). This
5251 greatly improves GDB's ability to find yacc/lex sources, and include files,
5252 especially if you are debugging your program from a directory different from
5253 the one that contains your sources.
5255 We also fixed a bug which caused difficulty with listing and setting
5256 breakpoints in include files which contain C code. (In the past, you had to
5257 try twice in order to list an include file that you hadn't looked at before.)
5259 * Interesting infernals change
5261 GDB now deals with arbitrary numbers of sections, where the symbols for each
5262 section must be relocated relative to that section's landing place in the
5263 target's address space. This work was needed to support ELF with embedded
5264 stabs used by Solaris-2.0.
5266 * Bug fixes (of course!)
5268 There have been loads of fixes for the following things:
5269 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5270 i960, stabs, DOS(GO32), procfs, etc...
5272 See the ChangeLog for details.
5274 *** Changes in GDB-4.5:
5276 * New machines supported (host and target)
5278 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5280 SGI Irix-4.x mips-sgi-irix4 or iris4
5282 * New malloc package
5284 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5285 Mmalloc is capable of handling mutiple heaps of memory. It is also
5286 capable of saving a heap to a file, and then mapping it back in later.
5287 This can be used to greatly speedup the startup of GDB by using a
5288 pre-parsed symbol table which lives in a mmalloc managed heap. For
5289 more details, please read mmalloc/mmalloc.texi.
5293 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5294 'help info proc' for details.
5296 * MIPS ecoff symbol table format
5298 The code that reads MIPS symbol table format is now supported on all hosts.
5299 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5302 * File name changes for MS-DOS
5304 Many files in the config directories have been renamed to make it easier to
5305 support GDB on MS-DOSe systems (which have very restrictive file name
5306 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5307 environment) is close to working but has some remaining problems. Note
5308 that debugging of DOS programs is not supported, due to limitations
5309 in the ``operating system'', but it can be used to host cross-debugging.
5311 * Cross byte order fixes
5313 Many fixes have been made to support cross debugging of Sparc and MIPS
5314 targets from hosts whose byte order differs.
5316 * New -mapped and -readnow options
5318 If memory-mapped files are available on your system through the 'mmap'
5319 system call, you can use the -mapped option on the `file' or
5320 `symbol-file' commands to cause GDB to write the symbols from your
5321 program into a reusable file. If the program you are debugging is
5322 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5323 Future GDB debugging sessions will notice the presence of this file,
5324 and will quickly map in symbol information from it, rather than reading
5325 the symbol table from the executable program. Using the '-mapped'
5326 option in a GDB `file' or `symbol-file' command has the same effect as
5327 starting GDB with the '-mapped' command-line option.
5329 You can cause GDB to read the entire symbol table immediately by using
5330 the '-readnow' option with any of the commands that load symbol table
5331 information (or on the GDB command line). This makes the command
5332 slower, but makes future operations faster.
5334 The -mapped and -readnow options are typically combined in order to
5335 build a `fred.syms' file that contains complete symbol information.
5336 A simple GDB invocation to do nothing but build a `.syms' file for future
5339 gdb -batch -nx -mapped -readnow programname
5341 The `.syms' file is specific to the host machine on which GDB is run.
5342 It holds an exact image of GDB's internal symbol table. It cannot be
5343 shared across multiple host platforms.
5345 * longjmp() handling
5347 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5348 siglongjmp() without losing control. This feature has not yet been ported to
5349 all systems. It currently works on many 386 platforms, all MIPS-based
5350 platforms (SGI, DECstation, etc), and Sun3/4.
5354 Preliminary work has been put in to support the new Solaris OS from Sun. At
5355 this time, it can control and debug processes, but it is not capable of
5360 As always, many many bug fixes. The major areas were with g++, and mipsread.
5361 People using the MIPS-based platforms should experience fewer mysterious
5362 crashes and trashed symbol tables.
5364 *** Changes in GDB-4.4:
5366 * New machines supported (host and target)
5368 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5370 BSD Reno on Vax vax-dec-bsd
5371 Ultrix on Vax vax-dec-ultrix
5373 * New machines supported (target)
5375 AMD 29000 embedded, using EBMON a29k-none-none
5379 GDB continues to improve its handling of C++. `References' work better.
5380 The demangler has also been improved, and now deals with symbols mangled as
5381 per the Annotated C++ Reference Guide.
5383 GDB also now handles `stabs' symbol information embedded in MIPS
5384 `ecoff' symbol tables. Since the ecoff format was not easily
5385 extensible to handle new languages such as C++, this appeared to be a
5386 good way to put C++ debugging info into MIPS binaries. This option
5387 will be supported in the GNU C compiler, version 2, when it is
5390 * New features for SVR4
5392 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5393 shared libraries. Debugging dynamically linked programs should present
5394 only minor differences from debugging statically linked programs.
5396 The `info proc' command will print out information about any process
5397 on an SVR4 system (including the one you are debugging). At the moment,
5398 it prints the address mappings of the process.
5400 If you bring up GDB on another SVR4 system, please send mail to
5401 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5403 * Better dynamic linking support in SunOS
5405 Reading symbols from shared libraries which contain debugging symbols
5406 now works properly. However, there remain issues such as automatic
5407 skipping of `transfer vector' code during function calls, which
5408 make it harder to debug code in a shared library, than to debug the
5409 same code linked statically.
5413 GDB is now using the latest `getopt' routines from the FSF. This
5414 version accepts the -- prefix for options with long names. GDB will
5415 continue to accept the old forms (-option and +option) as well.
5416 Various single letter abbreviations for options have been explicity
5417 added to the option table so that they won't get overshadowed in the
5418 future by other options that begin with the same letter.
5422 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5423 Many assorted bugs have been handled. Many more remain to be handled.
5424 See the various ChangeLog files (primarily in gdb and bfd) for details.
5427 *** Changes in GDB-4.3:
5429 * New machines supported (host and target)
5431 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5432 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5433 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5435 * Almost SCO Unix support
5437 We had hoped to support:
5438 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5439 (except for core file support), but we discovered very late in the release
5440 that it has problems with process groups that render gdb unusable. Sorry
5441 about that. I encourage people to fix it and post the fixes.
5443 * Preliminary ELF and DWARF support
5445 GDB can read ELF object files on System V Release 4, and can handle
5446 debugging records for C, in DWARF format, in ELF files. This support
5447 is preliminary. If you bring up GDB on another SVR4 system, please
5448 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5453 GDB now uses the latest `readline' library. One user-visible change
5454 is that two tabs will list possible command completions, which previously
5455 required typing M-? (meta-question mark, or ESC ?).
5459 The `stepi' bug that many of you noticed has been squashed.
5460 Many bugs in C++ have been handled. Many more remain to be handled.
5461 See the various ChangeLog files (primarily in gdb and bfd) for details.
5463 * State of the MIPS world (in case you wondered):
5465 GDB can understand the symbol tables emitted by the compilers
5466 supplied by most vendors of MIPS-based machines, including DEC. These
5467 symbol tables are in a format that essentially nobody else uses.
5469 Some versions of gcc come with an assembler post-processor called
5470 mips-tfile. This program is required if you want to do source-level
5471 debugging of gcc-compiled programs. I believe FSF does not ship
5472 mips-tfile with gcc version 1, but it will eventually come with gcc
5475 Debugging of g++ output remains a problem. g++ version 1.xx does not
5476 really support it at all. (If you're lucky, you should be able to get
5477 line numbers and stack traces to work, but no parameters or local
5478 variables.) With some work it should be possible to improve the
5481 When gcc version 2 is released, you will have somewhat better luck.
5482 However, even then you will get confusing results for inheritance and
5485 We will eventually provide full debugging of g++ output on
5486 DECstations. This will probably involve some kind of stabs-in-ecoff
5487 encapulation, but the details have not been worked out yet.
5490 *** Changes in GDB-4.2:
5492 * Improved configuration
5494 Only one copy of `configure' exists now, and it is not self-modifying.
5495 Porting BFD is simpler.
5499 The `step' and `next' commands now only stop at the first instruction
5500 of a source line. This prevents the multiple stops that used to occur
5501 in switch statements, for-loops, etc. `Step' continues to stop if a
5502 function that has debugging information is called within the line.
5506 Lots of small bugs fixed. More remain.
5508 * New host supported (not target)
5510 Intel 386 PC clone running Mach i386-none-mach
5513 *** Changes in GDB-4.1:
5515 * Multiple source language support
5517 GDB now has internal scaffolding to handle several source languages.
5518 It determines the type of each source file from its filename extension,
5519 and will switch expression parsing and number formatting to match the
5520 language of the function in the currently selected stack frame.
5521 You can also specifically set the language to be used, with
5522 `set language c' or `set language modula-2'.
5526 GDB now has preliminary support for the GNU Modula-2 compiler,
5527 currently under development at the State University of New York at
5528 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5529 continue through the fall of 1991 and into 1992.
5531 Other Modula-2 compilers are currently not supported, and attempting to
5532 debug programs compiled with them will likely result in an error as the
5533 symbol table is read. Feel free to work on it, though!
5535 There are hooks in GDB for strict type checking and range checking,
5536 in the `Modula-2 philosophy', but they do not currently work.
5540 GDB can now write to executable and core files (e.g. patch
5541 a variable's value). You must turn this switch on, specify
5542 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5543 by assigning a new value to a variable. Modifications take
5546 * Automatic SunOS shared library reading
5548 When you run your program, GDB automatically determines where its
5549 shared libraries (if any) have been loaded, and reads their symbols.
5550 The `share' command is no longer needed. This also works when
5551 examining core files.
5555 You can specify the number of lines that the `list' command shows.
5558 * New machines supported (host and target)
5560 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5561 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5562 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5564 * New hosts supported (not targets)
5566 IBM RT/PC: romp-ibm-aix or rtpc
5568 * New targets supported (not hosts)
5570 AMD 29000 embedded with COFF a29k-none-coff
5571 AMD 29000 embedded with a.out a29k-none-aout
5572 Ultracomputer remote kernel debug a29k-nyu-kern
5574 * New remote interfaces
5580 *** Changes in GDB-4.0:
5584 Wide output is wrapped at good places to make the output more readable.
5586 Gdb now supports cross-debugging from a host machine of one type to a
5587 target machine of another type. Communication with the target system
5588 is over serial lines. The ``target'' command handles connecting to the
5589 remote system; the ``load'' command will download a program into the
5590 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5591 also supports debugging of realtime processes running under VxWorks,
5592 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5593 stub on the target system.
5595 New CPUs supported include the AMD 29000 and Intel 960.
5597 GDB now reads object files and symbol tables via a ``binary file''
5598 library, which allows a single copy of GDB to debug programs of multiple
5599 object file types such as a.out and coff.
5601 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5602 refcard.dvi and refcard.ps are available to format it).
5605 * Control-Variable user interface simplified
5607 All variables that control the operation of the debugger can be set
5608 by the ``set'' command, and displayed by the ``show'' command.
5610 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5611 ``Show prompt'' produces the response:
5612 Gdb's prompt is new-gdb=>.
5614 What follows are the NEW set commands. The command ``help set'' will
5615 print a complete list of old and new set commands. ``help set FOO''
5616 will give a longer description of the variable FOO. ``show'' will show
5617 all of the variable descriptions and their current settings.
5619 confirm on/off: Enables warning questions for operations that are
5620 hard to recover from, e.g. rerunning the program while
5621 it is already running. Default is ON.
5623 editing on/off: Enables EMACS style command line editing
5624 of input. Previous lines can be recalled with
5625 control-P, the current line can be edited with control-B,
5626 you can search for commands with control-R, etc.
5629 history filename NAME: NAME is where the gdb command history
5630 will be stored. The default is .gdb_history,
5631 or the value of the environment variable
5634 history size N: The size, in commands, of the command history. The
5635 default is 256, or the value of the environment variable
5638 history save on/off: If this value is set to ON, the history file will
5639 be saved after exiting gdb. If set to OFF, the
5640 file will not be saved. The default is OFF.
5642 history expansion on/off: If this value is set to ON, then csh-like
5643 history expansion will be performed on
5644 command line input. The default is OFF.
5646 radix N: Sets the default radix for input and output. It can be set
5647 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5648 in the current radix, so "set radix 10" is always a no-op.
5650 height N: This integer value is the number of lines on a page. Default
5651 is 24, the current `stty rows'' setting, or the ``li#''
5652 setting from the termcap entry matching the environment
5655 width N: This integer value is the number of characters on a line.
5656 Default is 80, the current `stty cols'' setting, or the ``co#''
5657 setting from the termcap entry matching the environment
5660 Note: ``set screensize'' is obsolete. Use ``set height'' and
5661 ``set width'' instead.
5663 print address on/off: Print memory addresses in various command displays,
5664 such as stack traces and structure values. Gdb looks
5665 more ``symbolic'' if you turn this off; it looks more
5666 ``machine level'' with it on. Default is ON.
5668 print array on/off: Prettyprint arrays. New convenient format! Default
5671 print demangle on/off: Print C++ symbols in "source" form if on,
5674 print asm-demangle on/off: Same, for assembler level printouts
5677 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5680 * Support for Epoch Environment.
5682 The epoch environment is a version of Emacs v18 with windowing. One
5683 new command, ``inspect'', is identical to ``print'', except that if you
5684 are running in the epoch environment, the value is printed in its own
5688 * Support for Shared Libraries
5690 GDB can now debug programs and core files that use SunOS shared libraries.
5691 Symbols from a shared library cannot be referenced
5692 before the shared library has been linked with the program (this
5693 happens after you type ``run'' and before the function main() is entered).
5694 At any time after this linking (including when examining core files
5695 from dynamically linked programs), gdb reads the symbols from each
5696 shared library when you type the ``sharedlibrary'' command.
5697 It can be abbreviated ``share''.
5699 sharedlibrary REGEXP: Load shared object library symbols for files
5700 matching a unix regular expression. No argument
5701 indicates to load symbols for all shared libraries.
5703 info sharedlibrary: Status of loaded shared libraries.
5708 A watchpoint stops execution of a program whenever the value of an
5709 expression changes. Checking for this slows down execution
5710 tremendously whenever you are in the scope of the expression, but is
5711 quite useful for catching tough ``bit-spreader'' or pointer misuse
5712 problems. Some machines such as the 386 have hardware for doing this
5713 more quickly, and future versions of gdb will use this hardware.
5715 watch EXP: Set a watchpoint (breakpoint) for an expression.
5717 info watchpoints: Information about your watchpoints.
5719 delete N: Deletes watchpoint number N (same as breakpoints).
5720 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5721 enable N: Re-enables watchpoint number N (same as breakpoints).
5724 * C++ multiple inheritance
5726 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5729 * C++ exception handling
5731 Gdb now supports limited C++ exception handling. Besides the existing
5732 ability to breakpoint on an exception handler, gdb can breakpoint on
5733 the raising of an exception (before the stack is peeled back to the
5736 catch FOO: If there is a FOO exception handler in the dynamic scope,
5737 set a breakpoint to catch exceptions which may be raised there.
5738 Multiple exceptions (``catch foo bar baz'') may be caught.
5740 info catch: Lists all exceptions which may be caught in the
5741 current stack frame.
5744 * Minor command changes
5746 The command ``call func (arg, arg, ...)'' now acts like the print
5747 command, except it does not print or save a value if the function's result
5748 is void. This is similar to dbx usage.
5750 The ``up'' and ``down'' commands now always print the frame they end up
5751 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5752 frames without printing.
5754 * New directory command
5756 'dir' now adds directories to the FRONT of the source search path.
5757 The path starts off empty. Source files that contain debug information
5758 about the directory in which they were compiled can be found even
5759 with an empty path; Sun CC and GCC include this information. If GDB can't
5760 find your source file in the current directory, type "dir .".
5762 * Configuring GDB for compilation
5764 For normal use, type ``./configure host''. See README or gdb.texinfo
5767 GDB now handles cross debugging. If you are remotely debugging between
5768 two different machines, type ``./configure host -target=targ''.
5769 Host is the machine where GDB will run; targ is the machine
5770 where the program that you are debugging will run.
5772 * GDB now supports access to Intel(R) MPX registers on GNU/Linux.
5774 * Support for Intel(R) AVX-512 registers on GNU/Linux.
5776 Support displaying and modifying Intel(R) AVX-512 registers $zmm0 - $zmm31 and
5777 $k0 - $k7 on GNU/Linux.