1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * New convenience function "$_isvoid", to check whether an expression
7 is void. A void expression is an expression where the type of the
8 result is "void". For example, some convenience variables may be
9 "void" when evaluated (e.g., "$_exitcode" before the execution of
10 the program being debugged; or an undefined convenience variable).
11 Another example, when calling a function whose return type is
14 * The "maintenance print objfiles" command now takes an optional regexp.
16 * The "catch syscall" command now works on arm*-linux* targets.
18 * GDB now consistently shows "<not saved>" when printing values of
19 registers the debug info indicates have not been saved in the frame
20 and there's nowhere to retrieve them from
21 (callee-saved/call-clobbered registers):
26 (gdb) info registers rax
29 Before, the former would print "<optimized out>", and the latter
30 "*value not available*".
34 ** Frame filters and frame decorators have been added.
38 Nios II ELF nios2*-*-elf
39 Nios II GNU/Linux nios2*-*-linux
40 Texas Instruments MSP430 msp430*-*-elf
42 * Removed native configurations
44 Support for these a.out NetBSD and OpenBSD obsolete configurations has
45 been removed. ELF variants of these configurations are kept supported.
47 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
48 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
49 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
50 i[34567]86-*-openbsd3.[0-3]
51 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
52 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
53 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
57 Like "catch throw", but catches a re-thrown exception.
59 Renamed from old "maint check-symtabs".
61 Perform consistency checks on symtabs.
63 Expand symtabs matching an optional regexp.
66 Display the details of GDB configure-time options.
68 maint set|show per-command
69 maint set|show per-command space
70 maint set|show per-command time
71 maint set|show per-command symtab
72 Enable display of per-command gdb resource usage.
76 set debug symfile off|on
78 Control display of debugging info regarding reading symbol files and
79 symbol tables within those files
81 set print raw frame-arguments
82 show print raw frame-arguments
83 Set/show whether to print frame arguments in raw mode,
84 disregarding any defined pretty-printers.
86 set remote trace-status-packet
87 show remote trace-status-packet
88 Set/show the use of remote protocol qTStatus packet.
92 Control display of debugging messages related to Nios II targets.
96 Control whether target-assisted range stepping is enabled.
98 * You can now use a literal value 'unlimited' for options that
99 interpret 0 or -1 as meaning "unlimited". E.g., "set
100 trace-buffer-size unlimited" is now an alias for "set
101 trace-buffer-size -1" and "set height unlimited" is now an alias for
104 * New command-line options
106 Display the details of GDB configure-time options.
108 * The command 'tsave' can now support new option '-ctf' to save trace
109 buffer in Common Trace Format.
111 * Newly installed $prefix/bin/gcore acts as a shell interface for the
114 * GDB now implements the the C++ 'typeid' operator.
116 * The new convenience variable $_exception holds the exception being
117 thrown or caught at an exception-related catchpoint.
119 * The exception-related catchpoints, like "catch throw", now accept a
120 regular expression which can be used to filter exceptions by type.
124 ** The -trace-save MI command can optionally save trace buffer in Common
127 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
129 ** The command -data-list-register-values now accepts an optional
130 "--skip-unavailable" option. When used, only the available registers
133 ** The new command -trace-frame-collected dumps collected variables,
134 computed expressions, tvars, memory and registers in a traceframe.
136 ** The commands -stack-list-locals, -stack-list-arguments and
137 -stack-list-variables now accept an option "--skip-unavailable".
138 When used, only the available locals or arguments are displayed.
140 ** The -exec-run command now accepts an optional "--start" option.
141 When used, the command follows the same semantics as the "start"
142 command, stopping the program's execution at the start of its
145 * New system-wide configuration scripts
146 A GDB installation now provides scripts suitable for use as system-wide
147 configuration scripts for the following systems:
151 * GDB now supports target-assigned range stepping with remote targets.
152 This improves the performance of stepping source lines by reducing
153 the number of control packets from/to GDB. See "New remote packets"
156 * GDB now understands the element 'tvar' in the XML traceframe info.
157 It has the id of the collected trace state variables.
159 * On S/390 targets that provide the transactional-execution feature,
160 the program interruption transaction diagnostic block (TDB) is now
161 represented as a number of additional "registers" in GDB.
167 The vCont packet supports a new 'r' action, that tells the remote
168 stub to step through an address range itself, without GDB
169 involvemement at each single-step.
171 qXfer:libraries-svr4:read's annex
172 The previously unused annex of the qXfer:libraries-svr4:read packet
173 is now used to support passing an argument list. The remote stub
174 reports support for this argument list to GDB's qSupported query.
175 The defined arguments are "start" and "prev", used to reduce work
176 necessary for library list updating, resulting in significant
179 * New features in the GDB remote stub, GDBserver
181 ** GDBserver now supports target-assisted range stepping. Currently
182 enabled on x86/x86_64 GNU/Linux targets.
184 ** GDBserver now adds element 'tvar' in the XML in the reply to
185 'qXfer:traceframe-info:read'. It has the id of the collected
186 trace state variables.
188 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
191 * New 'z' formatter for printing and examining memory, this displays the
192 value as hexadecimal zero padded on the left to the size of the type.
194 * GDB can now use Windows x64 unwinding data.
196 *** Changes in GDB 7.6
198 * Target record has been renamed to record-full.
199 Record/replay is now enabled with the "record full" command.
200 This also affects settings that are associated with full record/replay
201 that have been moved from "set/show record" to "set/show record full":
203 set|show record full insn-number-max
204 set|show record full stop-at-limit
205 set|show record full memory-query
207 * A new record target "record-btrace" has been added. The new target
208 uses hardware support to record the control-flow of a process. It
209 does not support replaying the execution, but it implements the
210 below new commands for investigating the recorded execution log.
211 This new recording method can be enabled using:
215 The "record-btrace" target is only available on Intel Atom processors
216 and requires a Linux kernel 2.6.32 or later.
218 * Two new commands have been added for record/replay to give information
219 about the recorded execution without having to replay the execution.
220 The commands are only supported by "record btrace".
222 record instruction-history prints the execution history at
223 instruction granularity
225 record function-call-history prints the execution history at
228 * New native configurations
230 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
231 FreeBSD/powerpc powerpc*-*-freebsd
232 x86_64/Cygwin x86_64-*-cygwin*
233 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
237 ARM AArch64 aarch64*-*-elf
238 ARM AArch64 GNU/Linux aarch64*-*-linux
239 Lynx 178 PowerPC powerpc-*-lynx*178
240 x86_64/Cygwin x86_64-*-cygwin*
241 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
243 * If the configured location of system.gdbinit file (as given by the
244 --with-system-gdbinit option at configure time) is in the
245 data-directory (as specified by --with-gdb-datadir at configure
246 time) or in one of its subdirectories, then GDB will look for the
247 system-wide init file in the directory specified by the
248 --data-directory command-line option.
250 * New command line options:
252 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
253 other initialization files, unlike -nx which disables all of them.
255 * Removed command line options
257 -epoch This was used by the gdb mode in Epoch, an ancient fork of
260 * The 'ptype' and 'whatis' commands now accept an argument to control
263 * 'info proc' now works on some core files.
267 ** Vectors can be created with gdb.Type.vector.
269 ** Python's atexit.register now works in GDB.
271 ** Types can be pretty-printed via a Python API.
273 ** Python 3 is now supported (in addition to Python 2.4 or later)
275 ** New class gdb.Architecture exposes GDB's internal representation
276 of architecture in the Python API.
278 ** New method Frame.architecture returns the gdb.Architecture object
279 corresponding to the frame's architecture.
281 * New Python-based convenience functions:
283 ** $_memeq(buf1, buf2, length)
284 ** $_streq(str1, str2)
286 ** $_regex(str, regex)
288 * The 'cd' command now defaults to using '~' (the home directory) if not
291 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
292 default for GCC since November 2000.
294 * The command 'forward-search' can now be abbreviated as 'fo'.
296 * The command 'info tracepoints' can now display 'installed on target'
297 or 'not installed on target' for each non-pending location of tracepoint.
299 * New configure options
301 --enable-libmcheck/--disable-libmcheck
302 By default, development versions are built with -lmcheck on hosts
303 that support it, in order to help track memory corruption issues.
304 Release versions, on the other hand, are built without -lmcheck
305 by default. The --enable-libmcheck/--disable-libmcheck configure
306 options allow the user to override that default.
307 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
308 This configure option allows the user to build GDB with
309 libbabeltrace using which GDB can read Common Trace Format data.
311 * New commands (for set/show, see "New options" below)
314 Catch signals. This is similar to "handle", but allows commands and
315 conditions to be attached.
318 List the BFDs known to GDB.
320 python-interactive [command]
322 Start a Python interactive prompt, or evaluate the optional command
323 and print the result of expressions.
326 "py" is a new alias for "python".
328 enable type-printer [name]...
329 disable type-printer [name]...
330 Enable or disable type printers.
334 ** For the Renesas Super-H architecture, the "regs" command has been removed
335 (has been deprecated in GDB 7.5), and "info all-registers" should be used
340 set print type methods (on|off)
341 show print type methods
342 Control whether method declarations are displayed by "ptype".
343 The default is to show them.
345 set print type typedefs (on|off)
346 show print type typedefs
347 Control whether typedef definitions are displayed by "ptype".
348 The default is to show them.
350 set filename-display basename|relative|absolute
351 show filename-display
352 Control the way in which filenames is displayed.
353 The default is "relative", which preserves previous behavior.
355 set trace-buffer-size
356 show trace-buffer-size
357 Request target to change the size of trace buffer.
359 set remote trace-buffer-size-packet auto|on|off
360 show remote trace-buffer-size-packet
361 Control the use of the remote protocol `QTBuffer:size' packet.
365 Control display of debugging messages related to ARM AArch64.
368 set debug coff-pe-read
369 show debug coff-pe-read
370 Control display of debugging messages related to reading of COFF/PE
375 Control display of debugging messages related to Mach-O symbols
378 set debug notification
379 show debug notification
380 Control display of debugging info for async remote notification.
384 ** Command parameter changes are now notified using new async record
385 "=cmd-param-changed".
386 ** Trace frame changes caused by command "tfind" are now notified using
387 new async record "=traceframe-changed".
388 ** The creation, deletion and modification of trace state variables
389 are now notified using new async records "=tsv-created",
390 "=tsv-deleted" and "=tsv-modified".
391 ** The start and stop of process record are now notified using new
392 async record "=record-started" and "=record-stopped".
393 ** Memory changes are now notified using new async record
395 ** The data-disassemble command response will include a "fullname" field
396 containing the absolute file name when source has been requested.
397 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
398 command, to allow pattern filling of memory areas.
399 ** New commands "-catch-load"/"-catch-unload" added for intercepting
400 library load/unload events.
401 ** The response to breakpoint commands and breakpoint async records
402 includes an "installed" field containing a boolean state about each
403 non-pending tracepoint location is whether installed on target or not.
404 ** Output of the "-trace-status" command includes a "trace-file" field
405 containing the name of the trace file being examined. This field is
406 optional, and only present when examining a trace file.
407 ** The "fullname" field is now always present along with the "file" field,
408 even if the file cannot be found by GDB.
410 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
411 You must have the LZMA library available when configuring GDB for this
412 feature to be enabled. For more information, see:
413 http://fedoraproject.org/wiki/Features/MiniDebugInfo
418 Set the size of trace buffer. The remote stub reports support for this
419 packet to gdb's qSupported query.
422 Enable Branch Trace Store (BTS)-based branch tracing for the current
423 thread. The remote stub reports support for this packet to gdb's
427 Disable branch tracing for the current thread. The remote stub reports
428 support for this packet to gdb's qSupported query.
431 Read the traced branches for the current thread. The remote stub
432 reports support for this packet to gdb's qSupported query.
434 *** Changes in GDB 7.5
436 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
437 for more x32 ABI info.
439 * GDB now supports access to MIPS DSP registers on Linux targets.
441 * GDB now supports debugging microMIPS binaries.
443 * The "info os" command on GNU/Linux can now display information on
444 several new classes of objects managed by the operating system:
445 "info os procgroups" lists process groups
446 "info os files" lists file descriptors
447 "info os sockets" lists internet-domain sockets
448 "info os shm" lists shared-memory regions
449 "info os semaphores" lists semaphores
450 "info os msg" lists message queues
451 "info os modules" lists loaded kernel modules
453 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
454 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
455 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
456 options and inspect the probe arguments using the new $_probe_arg family
457 of convenience variables. You can obtain more information about SystemTap
458 in <http://sourceware.org/systemtap/>.
460 * GDB now supports reversible debugging on ARM, it allows you to
461 debug basic ARM and THUMB instructions, and provides
462 record/replay support.
464 * The option "symbol-reloading" has been deleted as it is no longer used.
468 ** GDB commands implemented in Python can now be put in command class
471 ** The "maint set python print-stack on|off" is now deleted.
473 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
474 apply "flag enum"-style pretty-printing to any enum.
476 ** gdb.lookup_symbol can now work when there is no current frame.
478 ** gdb.Symbol now has a 'line' attribute, holding the line number in
479 the source at which the symbol was defined.
481 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
482 method 'value'. The former indicates whether the symbol needs a
483 frame in order to compute its value, and the latter computes the
486 ** A new method 'referenced_value' on gdb.Value objects which can
487 dereference pointer as well as C++ reference values.
489 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
490 which return the global and static blocks (as gdb.Block objects),
491 of the underlying symbol table, respectively.
493 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
494 object associated with a PC value.
496 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
497 of the address range occupied by code for the current source line.
499 * Go language support.
500 GDB now supports debugging programs written in the Go programming
503 * GDBserver now supports stdio connections.
504 E.g. (gdb) target remote | ssh myhost gdbserver - hello
506 * The binary "gdbtui" can no longer be built or installed.
507 Use "gdb -tui" instead.
509 * GDB will now print "flag" enums specially. A flag enum is one where
510 all the enumerator values have no bits in common when pairwise
511 "and"ed. When printing a value whose type is a flag enum, GDB will
512 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
513 (gdb) print (enum E) 3
516 * The filename part of a linespec will now match trailing components
517 of a source file name. For example, "break gcc/expr.c:1000" will
518 now set a breakpoint in build/gcc/expr.c, but not
521 * The "info proc" and "generate-core-file" commands will now also
522 work on remote targets connected to GDBserver on Linux.
524 * The command "info catch" has been removed. It has been disabled
527 * The "catch exception" and "catch assert" commands now accept
528 a condition at the end of the command, much like the "break"
529 command does. For instance:
531 (gdb) catch exception Constraint_Error if Barrier = True
533 Previously, it was possible to add a condition to such catchpoints,
534 but it had to be done as a second step, after the catchpoint had been
535 created, using the "condition" command.
537 * The "info static-tracepoint-marker" command will now also work on
538 native Linux targets with in-process agent.
540 * GDB can now set breakpoints on inlined functions.
542 * The .gdb_index section has been updated to include symbols for
543 inlined functions. GDB will ignore older .gdb_index sections by
544 default, which could cause symbol files to be loaded more slowly
545 until their .gdb_index sections can be recreated. The new command
546 "set use-deprecated-index-sections on" will cause GDB to use any older
547 .gdb_index sections it finds. This will restore performance, but the
548 ability to set breakpoints on inlined functions will be lost in symbol
549 files with older .gdb_index sections.
551 The .gdb_index section has also been updated to record more information
552 about each symbol. This speeds up the "info variables", "info functions"
553 and "info types" commands when used with programs having the .gdb_index
554 section, as well as speeding up debugging with shared libraries using
555 the .gdb_index section.
557 * Ada support for GDB/MI Variable Objects has been added.
559 * GDB can now support 'breakpoint always-inserted mode' in 'record'
564 ** New command -info-os is the MI equivalent of "info os".
566 ** Output logs ("set logging" and related) now include MI output.
570 ** "set use-deprecated-index-sections on|off"
571 "show use-deprecated-index-sections on|off"
572 Controls the use of deprecated .gdb_index sections.
574 ** "catch load" and "catch unload" can be used to stop when a shared
575 library is loaded or unloaded, respectively.
577 ** "enable count" can be used to auto-disable a breakpoint after
580 ** "info vtbl" can be used to show the virtual method tables for
581 C++ and Java objects.
583 ** "explore" and its sub commands "explore value" and "explore type"
584 can be used to reccursively explore values and types of
585 expressions. These commands are available only if GDB is
586 configured with '--with-python'.
588 ** "info auto-load" shows status of all kinds of auto-loaded files,
589 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
590 sequences of commands files, "info auto-load python-scripts"
591 shows status of auto-loading Python script files,
592 "info auto-load local-gdbinit" shows status of loading init file
593 (.gdbinit) from current directory and "info auto-load libthread-db" shows
594 status of inferior specific thread debugging shared library loading.
596 ** "info auto-load-scripts", "set auto-load-scripts on|off"
597 and "show auto-load-scripts" commands have been deprecated, use their
598 "info auto-load python-scripts", "set auto-load python-scripts on|off"
599 and "show auto-load python-scripts" counterparts instead.
601 ** "dprintf location,format,args..." creates a dynamic printf, which
602 is basically a breakpoint that does a printf and immediately
603 resumes your program's execution, so it is like a printf that you
604 can insert dynamically at runtime instead of at compiletime.
606 ** "set print symbol"
608 Controls whether GDB attempts to display the symbol, if any,
609 corresponding to addresses it prints. This defaults to "on", but
610 you can set it to "off" to restore GDB's previous behavior.
612 * Deprecated commands
614 ** For the Renesas Super-H architecture, the "regs" command has been
615 deprecated, and "info all-registers" should be used instead.
619 Renesas RL78 rl78-*-elf
620 HP OpenVMS ia64 ia64-hp-openvms*
622 * GDBserver supports evaluation of breakpoint conditions. When
623 support is advertised by GDBserver, GDB may be told to send the
624 breakpoint conditions in bytecode form to GDBserver. GDBserver
625 will only report the breakpoint trigger to GDB when its condition
631 show mips compression
632 Select the compressed ISA encoding used in functions that have no symbol
633 information available. The encoding can be set to either of:
636 and is updated automatically from ELF file flags if available.
638 set breakpoint condition-evaluation
639 show breakpoint condition-evaluation
640 Control whether breakpoint conditions are evaluated by GDB ("host") or by
641 GDBserver ("target"). Default option "auto" chooses the most efficient
643 This option can improve debugger efficiency depending on the speed of the
647 Disable auto-loading globally.
650 Show auto-loading setting of all kinds of auto-loaded files.
652 set auto-load gdb-scripts on|off
653 show auto-load gdb-scripts
654 Control auto-loading of GDB canned sequences of commands files.
656 set auto-load python-scripts on|off
657 show auto-load python-scripts
658 Control auto-loading of Python script files.
660 set auto-load local-gdbinit on|off
661 show auto-load local-gdbinit
662 Control loading of init file (.gdbinit) from current directory.
664 set auto-load libthread-db on|off
665 show auto-load libthread-db
666 Control auto-loading of inferior specific thread debugging shared library.
668 set auto-load scripts-directory <dir1>[:<dir2>...]
669 show auto-load scripts-directory
670 Set a list of directories from which to load auto-loaded scripts.
671 Automatically loaded Python scripts and GDB scripts are located in one
672 of the directories listed by this option.
673 The delimiter (':' above) may differ according to the host platform.
675 set auto-load safe-path <dir1>[:<dir2>...]
676 show auto-load safe-path
677 Set a list of directories from which it is safe to auto-load files.
678 The delimiter (':' above) may differ according to the host platform.
680 set debug auto-load on|off
682 Control display of debugging info for auto-loading the files above.
684 set dprintf-style gdb|call|agent
686 Control the way in which a dynamic printf is performed; "gdb"
687 requests a GDB printf command, while "call" causes dprintf to call a
688 function in the inferior. "agent" requests that the target agent
689 (such as GDBserver) do the printing.
691 set dprintf-function <expr>
692 show dprintf-function
693 set dprintf-channel <expr>
695 Set the function and optional first argument to the call when using
696 the "call" style of dynamic printf.
698 set disconnected-dprintf on|off
699 show disconnected-dprintf
700 Control whether agent-style dynamic printfs continue to be in effect
701 after GDB disconnects.
703 * New configure options
706 Configure default value for the 'set auto-load scripts-directory'
707 setting above. It defaults to '$debugdir:$datadir/auto-load',
708 $debugdir representing global debugging info directories (available
709 via 'show debug-file-directory') and $datadir representing GDB's data
710 directory (available via 'show data-directory').
712 --with-auto-load-safe-path
713 Configure default value for the 'set auto-load safe-path' setting
714 above. It defaults to the --with-auto-load-dir setting.
716 --without-auto-load-safe-path
717 Set 'set auto-load safe-path' to '/', effectively disabling this
722 z0/z1 conditional breakpoints extension
724 The z0/z1 breakpoint insertion packets have been extended to carry
725 a list of conditional expressions over to the remote stub depending on the
726 condition evaluation mode. The use of this extension can be controlled
727 via the "set remote conditional-breakpoints-packet" command.
731 Specify the signals which the remote stub may pass to the debugged
732 program without GDB involvement.
734 * New command line options
736 --init-command=FILE, -ix Like --command, -x but execute it
737 before loading inferior.
738 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
739 execute it before loading inferior.
741 *** Changes in GDB 7.4
743 * GDB now handles ambiguous linespecs more consistently; the existing
744 FILE:LINE support has been expanded to other types of linespecs. A
745 breakpoint will now be set on all matching locations in all
746 inferiors, and locations will be added or removed according to
749 * GDB now allows you to skip uninteresting functions and files when
750 stepping with the "skip function" and "skip file" commands.
752 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
753 and "show remote hardware-watchpoint-length-limit". These allows to
754 set or show the maximum length limit (in bytes) of a remote
755 target hardware watchpoint.
757 This allows e.g. to use "unlimited" hardware watchpoints with the
758 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
759 watchpoints are slower than real hardware watchpoints but are
760 significantly faster than gdb software watchpoints.
764 ** The register_pretty_printer function in module gdb.printing now takes
765 an optional `replace' argument. If True, the new printer replaces any
768 ** The "maint set python print-stack on|off" command has been
769 deprecated and will be deleted in GDB 7.5.
770 A new command: "set python print-stack none|full|message" has
771 replaced it. Additionally, the default for "print-stack" is
772 now "message", which just prints the error message without
775 ** A prompt substitution hook (prompt_hook) is now available to the
778 ** A new Python module, gdb.prompt has been added to the GDB Python
779 modules library. This module provides functionality for
780 escape sequences in prompts (used by set/show
781 extended-prompt). These escape sequences are replaced by their
784 ** Python commands and convenience-functions located in
785 'data-directory'/python/gdb/command and
786 'data-directory'/python/gdb/function are now automatically loaded
789 ** Blocks now provide four new attributes. global_block and
790 static_block will return the global and static blocks
791 respectively. is_static and is_global are boolean attributes
792 that indicate if the block is one of those two types.
794 ** Symbols now provide the "type" attribute, the type of the symbol.
796 ** The "gdb.breakpoint" function has been deprecated in favor of
799 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
800 of a function. This class is based on the "finish" command
801 available in the CLI.
803 ** Type objects for struct and union types now allow access to
804 the fields using standard Python dictionary (mapping) methods.
805 For example, "some_type['myfield']" now works, as does
808 ** A new event "gdb.new_objfile" has been added, triggered by loading a
811 ** A new function, "deep_items" has been added to the gdb.types
812 module in the GDB Python modules library. This function returns
813 an iterator over the fields of a struct or union type. Unlike
814 the standard Python "iteritems" method, it will recursively traverse
815 any anonymous fields.
819 ** "*stopped" events can report several new "reason"s, such as
822 ** Breakpoint changes are now notified using new async records, like
823 "=breakpoint-modified".
825 ** New command -ada-task-info.
827 * libthread-db-search-path now supports two special values: $sdir and $pdir.
828 $sdir specifies the default system locations of shared libraries.
829 $pdir specifies the directory where the libpthread used by the application
832 GDB no longer looks in $sdir and $pdir after it has searched the directories
833 mentioned in libthread-db-search-path. If you want to search those
834 directories, they must be specified in libthread-db-search-path.
835 The default value of libthread-db-search-path on GNU/Linux and Solaris
836 systems is now "$sdir:$pdir".
838 $pdir is not supported by gdbserver, it is currently ignored.
839 $sdir is supported by gdbserver.
841 * New configure option --with-iconv-bin.
842 When using the internationalization support like the one in the GNU C
843 library, GDB will invoke the "iconv" program to get a list of supported
844 character sets. If this program lives in a non-standard location, one can
845 use this option to specify where to find it.
847 * When natively debugging programs on PowerPC BookE processors running
848 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
849 watchpoints, which specify a mask in addition to an address to watch.
850 The mask specifies that some bits of an address (the bits which are
851 reset in the mask) should be ignored when matching the address accessed
852 by the inferior against the watchpoint address. See the "PowerPC Embedded"
853 section in the user manual for more details.
855 * The new option --once causes GDBserver to stop listening for connections once
856 the first connection is made. The listening port used by GDBserver will
857 become available after that.
859 * New commands "info macros" and "alias" have been added.
861 * New function parameters suffix @entry specifies value of function parameter
862 at the time the function got called. Entry values are available only since
868 "!" is now an alias of the "shell" command.
869 Note that no space is needed between "!" and SHELL COMMAND.
873 watch EXPRESSION mask MASK_VALUE
874 The watch command now supports the mask argument which allows creation
875 of masked watchpoints, if the current architecture supports this feature.
877 info auto-load-scripts [REGEXP]
878 This command was formerly named "maintenance print section-scripts".
879 It is now generally useful and is no longer a maintenance-only command.
881 info macro [-all] [--] MACRO
882 The info macro command has new options `-all' and `--'. The first for
883 printing all definitions of a macro. The second for explicitly specifying
884 the end of arguments and the beginning of the macro name in case the macro
885 name starts with a hyphen.
887 collect[/s] EXPRESSIONS
888 The tracepoint collect command now takes an optional modifier "/s"
889 that directs it to dereference pointer-to-character types and
890 collect the bytes of memory up to a zero byte. The behavior is
891 similar to what you see when you use the regular print command on a
892 string. An optional integer following the "/s" sets a bound on the
893 number of bytes that will be collected.
896 The trace start command now interprets any supplied arguments as a
897 note to be recorded with the trace run, with an effect similar to
898 setting the variable trace-notes.
901 The trace stop command now interprets any arguments as a note to be
902 mentioned along with the tstatus report that the trace was stopped
903 with a command. The effect is similar to setting the variable
906 * Tracepoints can now be enabled and disabled at any time after a trace
907 experiment has been started using the standard "enable" and "disable"
908 commands. It is now possible to start a trace experiment with no enabled
909 tracepoints; GDB will display a warning, but will allow the experiment to
910 begin, assuming that tracepoints will be enabled as needed while the trace
913 * Fast tracepoints on 32-bit x86-architectures can now be placed at
914 locations with 4-byte instructions, when they were previously
915 limited to locations with instructions of 5 bytes or longer.
919 set debug dwarf2-read
920 show debug dwarf2-read
921 Turns on or off display of debugging messages related to reading
922 DWARF debug info. The default is off.
924 set debug symtab-create
925 show debug symtab-create
926 Turns on or off display of debugging messages related to symbol table
927 creation. The default is off.
931 Set the GDB prompt, and allow escape sequences to be inserted to
932 display miscellaneous information (see 'help set extended-prompt'
933 for the list of sequences). This prompt (and any information
934 accessed through the escape sequences) is updated every time the
937 set print entry-values (both|compact|default|if-needed|no|only|preferred)
938 show print entry-values
939 Set printing of frame argument values at function entry. In some cases
940 GDB can determine the value of function argument which was passed by the
941 function caller, even if the value was modified inside the called function.
943 set debug entry-values
944 show debug entry-values
945 Control display of debugging info for determining frame argument values at
946 function entry and virtual tail call frames.
948 set basenames-may-differ
949 show basenames-may-differ
950 Set whether a source file may have multiple base names.
951 (A "base name" is the name of a file with the directory part removed.
952 Example: The base name of "/home/user/hello.c" is "hello.c".)
953 If set, GDB will canonicalize file names (e.g., expand symlinks)
954 before comparing them. Canonicalization is an expensive operation,
955 but it allows the same file be known by more than one base name.
956 If not set (the default), all source files are assumed to have just
957 one base name, and gdb will do file name comparisons more efficiently.
963 Set a user name and notes for the current and any future trace runs.
964 This is useful for long-running and/or disconnected traces, to
965 inform others (or yourself) as to who is running the trace, supply
966 contact information, or otherwise explain what is going on.
969 show trace-stop-notes
970 Set a note attached to the trace run, that is displayed when the
971 trace has been stopped by a tstop command. This is useful for
972 instance as an explanation, if you are stopping a trace run that was
973 started by someone else.
979 Dynamically enable a tracepoint in a started trace experiment.
983 Dynamically disable a tracepoint in a started trace experiment.
987 Set the user and notes of the trace run.
991 Query the current status of a tracepoint.
995 Query the minimum length of instruction at which a fast tracepoint may
998 * Dcache size (number of lines) and line-size are now runtime-configurable
999 via "set dcache line" and "set dcache line-size" commands.
1003 Texas Instruments TMS320C6x tic6x-*-*
1007 Renesas RL78 rl78-*-elf
1009 *** Changes in GDB 7.3.1
1011 * The build failure for NetBSD and OpenBSD targets have now been fixed.
1013 *** Changes in GDB 7.3
1015 * GDB has a new command: "thread find [REGEXP]".
1016 It finds the thread id whose name, target id, or thread extra info
1017 matches the given regular expression.
1019 * The "catch syscall" command now works on mips*-linux* targets.
1021 * The -data-disassemble MI command now supports modes 2 and 3 for
1022 dumping the instruction opcodes.
1024 * New command line options
1026 -data-directory DIR Specify DIR as the "data-directory".
1027 This is mostly for testing purposes.
1029 * The "maint set python auto-load on|off" command has been renamed to
1030 "set auto-load-scripts on|off".
1032 * GDB has a new command: "set directories".
1033 It is like the "dir" command except that it replaces the
1034 source path list instead of augmenting it.
1036 * GDB now understands thread names.
1038 On GNU/Linux, "info threads" will display the thread name as set by
1039 prctl or pthread_setname_np.
1041 There is also a new command, "thread name", which can be used to
1042 assign a name internally for GDB to display.
1045 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
1046 has been integrated into GDB.
1050 ** The function gdb.Write now accepts an optional keyword 'stream'.
1051 This keyword, when provided, will direct the output to either
1052 stdout, stderr, or GDB's logging output.
1054 ** Parameters can now be be sub-classed in Python, and in particular
1055 you may implement the get_set_doc and get_show_doc functions.
1056 This improves how Parameter set/show documentation is processed
1057 and allows for more dynamic content.
1059 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1060 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1061 have an is_valid method.
1063 ** Breakpoints can now be sub-classed in Python, and in particular
1064 you may implement a 'stop' function that is executed each time
1065 the inferior reaches that breakpoint.
1067 ** New function gdb.lookup_global_symbol looks up a global symbol.
1069 ** GDB values in Python are now callable if the value represents a
1070 function. For example, if 'some_value' represents a function that
1071 takes two integer parameters and returns a value, you can call
1072 that function like so:
1074 result = some_value (10,20)
1076 ** Module gdb.types has been added.
1077 It contains a collection of utilities for working with gdb.Types objects:
1078 get_basic_type, has_field, make_enum_dict.
1080 ** Module gdb.printing has been added.
1081 It contains utilities for writing and registering pretty-printers.
1082 New classes: PrettyPrinter, SubPrettyPrinter,
1083 RegexpCollectionPrettyPrinter.
1084 New function: register_pretty_printer.
1086 ** New commands "info pretty-printers", "enable pretty-printer" and
1087 "disable pretty-printer" have been added.
1089 ** gdb.parameter("directories") is now available.
1091 ** New function gdb.newest_frame returns the newest frame in the
1094 ** The gdb.InferiorThread class has a new "name" attribute. This
1095 holds the thread's name.
1097 ** Python Support for Inferior events.
1098 Python scripts can add observers to be notified of events
1099 occurring in the process being debugged.
1100 The following events are currently supported:
1101 - gdb.events.cont Continue event.
1102 - gdb.events.exited Inferior exited event.
1103 - gdb.events.stop Signal received, and Breakpoint hit events.
1107 ** GDB now puts template parameters in scope when debugging in an
1108 instantiation. For example, if you have:
1110 template<int X> int func (void) { return X; }
1112 then if you step into func<5>, "print X" will show "5". This
1113 feature requires proper debuginfo support from the compiler; it
1114 was added to GCC 4.5.
1116 ** The motion commands "next", "finish", "until", and "advance" now
1117 work better when exceptions are thrown. In particular, GDB will
1118 no longer lose control of the inferior; instead, the GDB will
1119 stop the inferior at the point at which the exception is caught.
1120 This functionality requires a change in the exception handling
1121 code that was introduced in GCC 4.5.
1123 * GDB now follows GCC's rules on accessing volatile objects when
1124 reading or writing target state during expression evaluation.
1125 One notable difference to prior behavior is that "print x = 0"
1126 no longer generates a read of x; the value of the assignment is
1127 now always taken directly from the value being assigned.
1129 * GDB now has some support for using labels in the program's source in
1130 linespecs. For instance, you can use "advance label" to continue
1131 execution to a label.
1133 * GDB now has support for reading and writing a new .gdb_index
1134 section. This section holds a fast index of DWARF debugging
1135 information and can be used to greatly speed up GDB startup and
1136 operation. See the documentation for `save gdb-index' for details.
1138 * The "watch" command now accepts an optional "-location" argument.
1139 When used, this causes GDB to watch the memory referred to by the
1140 expression. Such a watchpoint is never deleted due to it going out
1143 * GDB now supports thread debugging of core dumps on GNU/Linux.
1145 GDB now activates thread debugging using the libthread_db library
1146 when debugging GNU/Linux core dumps, similarly to when debugging
1147 live processes. As a result, when debugging a core dump file, GDB
1148 is now able to display pthread_t ids of threads. For example, "info
1149 threads" shows the same output as when debugging the process when it
1150 was live. In earlier releases, you'd see something like this:
1153 * 1 LWP 6780 main () at main.c:10
1155 While now you see this:
1158 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1160 It is also now possible to inspect TLS variables when debugging core
1163 When debugging a core dump generated on a machine other than the one
1164 used to run GDB, you may need to point GDB at the correct
1165 libthread_db library with the "set libthread-db-search-path"
1166 command. See the user manual for more details on this command.
1168 * When natively debugging programs on PowerPC BookE processors running
1169 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1170 which stop execution of the inferior whenever it executes an instruction
1171 at any address within the specified range. See the "PowerPC Embedded"
1172 section in the user manual for more details.
1174 * New features in the GDB remote stub, GDBserver
1176 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1177 and i686 LynxOS (version 5.x).
1179 ** GDBserver is now supported on Blackfin Linux.
1181 * New native configurations
1183 ia64 HP-UX ia64-*-hpux*
1187 Analog Devices, Inc. Blackfin Processor bfin-*
1189 * Ada task switching is now supported on sparc-elf targets when
1190 debugging a program using the Ravenscar Profile. For more information,
1191 see the "Tasking Support when using the Ravenscar Profile" section
1192 in the GDB user manual.
1194 * Guile support was removed.
1196 * New features in the GNU simulator
1198 ** The --map-info flag lists all known core mappings.
1200 ** CFI flashes may be simulated via the "cfi" device.
1202 *** Changes in GDB 7.2
1204 * Shared library support for remote targets by default
1206 When GDB is configured for a generic, non-OS specific target, like
1207 for example, --target=arm-eabi or one of the many *-*-elf targets,
1208 GDB now queries remote stubs for loaded shared libraries using the
1209 `qXfer:libraries:read' packet. Previously, shared library support
1210 was always disabled for such configurations.
1214 ** Argument Dependent Lookup (ADL)
1216 In C++ ADL lookup directs function search to the namespaces of its
1217 arguments even if the namespace has not been imported.
1227 Here the compiler will search for `foo' in the namespace of 'b'
1228 and find A::foo. GDB now supports this. This construct is commonly
1229 used in the Standard Template Library for operators.
1231 ** Improved User Defined Operator Support
1233 In addition to member operators, GDB now supports lookup of operators
1234 defined in a namespace and imported with a `using' directive, operators
1235 defined in the global scope, operators imported implicitly from an
1236 anonymous namespace, and the ADL operators mentioned in the previous
1238 GDB now also supports proper overload resolution for all the previously
1239 mentioned flavors of operators.
1241 ** static const class members
1243 Printing of static const class members that are initialized in the
1244 class definition has been fixed.
1246 * Windows Thread Information Block access.
1248 On Windows targets, GDB now supports displaying the Windows Thread
1249 Information Block (TIB) structure. This structure is visible either
1250 by using the new command `info w32 thread-information-block' or, by
1251 dereferencing the new convenience variable named `$_tlb', a
1252 thread-specific pointer to the TIB. This feature is also supported
1253 when remote debugging using GDBserver.
1255 * Static tracepoints
1257 Static tracepoints are calls in the user program into a tracing
1258 library. One such library is a port of the LTTng kernel tracer to
1259 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1260 When debugging with GDBserver, GDB now supports combining the GDB
1261 tracepoint machinery with such libraries. For example: the user can
1262 use GDB to probe a static tracepoint marker (a call from the user
1263 program into the tracing library) with the new "strace" command (see
1264 "New commands" below). This creates a "static tracepoint" in the
1265 breakpoint list, that can be manipulated with the same feature set
1266 as fast and regular tracepoints. E.g., collect registers, local and
1267 global variables, collect trace state variables, and define
1268 tracepoint conditions. In addition, the user can collect extra
1269 static tracepoint marker specific data, by collecting the new
1270 $_sdata internal variable. When analyzing the trace buffer, you can
1271 inspect $_sdata like any other variable available to GDB. For more
1272 information, see the "Tracepoints" chapter in GDB user manual. New
1273 remote packets have been defined to support static tracepoints, see
1274 the "New remote packets" section below.
1276 * Better reconstruction of tracepoints after disconnected tracing
1278 GDB will attempt to download the original source form of tracepoint
1279 definitions when starting a trace run, and then will upload these
1280 upon reconnection to the target, resulting in a more accurate
1281 reconstruction of the tracepoints that are in use on the target.
1285 You can now exercise direct control over the ways that GDB can
1286 affect your program. For instance, you can disallow the setting of
1287 breakpoints, so that the program can run continuously (assuming
1288 non-stop mode). In addition, the "observer" variable is available
1289 to switch all of the different controls; in observer mode, GDB
1290 cannot affect the target's behavior at all, which is useful for
1291 tasks like diagnosing live systems in the field.
1293 * The new convenience variable $_thread holds the number of the
1296 * New remote packets
1300 Return the address of the Windows Thread Information Block of a given thread.
1304 In response to several of the tracepoint packets, the target may now
1305 also respond with a number of intermediate `qRelocInsn' request
1306 packets before the final result packet, to have GDB handle
1307 relocating an instruction to execute at a different address. This
1308 is particularly useful for stubs that support fast tracepoints. GDB
1309 reports support for this feature in the qSupported packet.
1313 List static tracepoint markers in the target program.
1317 List static tracepoint markers at a given address in the target
1320 qXfer:statictrace:read
1322 Read the static trace data collected (by a `collect $_sdata'
1323 tracepoint action). The remote stub reports support for this packet
1324 to gdb's qSupported query.
1328 Send the current settings of GDB's permission flags.
1332 Send part of the source (textual) form of a tracepoint definition,
1333 which includes location, conditional, and action list.
1335 * The source command now accepts a -s option to force searching for the
1336 script in the source search path even if the script name specifies
1339 * New features in the GDB remote stub, GDBserver
1341 - GDBserver now support tracepoints (including fast tracepoints, and
1342 static tracepoints). The feature is currently supported by the
1343 i386-linux and amd64-linux builds. See the "Tracepoints support
1344 in gdbserver" section in the manual for more information.
1346 GDBserver JIT compiles the tracepoint's conditional agent
1347 expression bytecode into native code whenever possible for low
1348 overhead dynamic tracepoints conditionals. For such tracepoints,
1349 an expression that examines program state is evaluated when the
1350 tracepoint is reached, in order to determine whether to capture
1351 trace data. If the condition is simple and false, processing the
1352 tracepoint finishes very quickly and no data is gathered.
1354 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1355 for static tracepoints support.
1357 - GDBserver now supports x86_64 Windows 64-bit debugging.
1359 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1360 it understands register description.
1362 * The --batch flag now disables pagination and queries.
1364 * X86 general purpose registers
1366 GDB now supports reading/writing byte, word and double-word x86
1367 general purpose registers directly. This means you can use, say,
1368 $ah or $ax to refer, respectively, to the byte register AH and
1369 16-bit word register AX that are actually portions of the 32-bit
1370 register EAX or 64-bit register RAX.
1372 * The `commands' command now accepts a range of breakpoints to modify.
1373 A plain `commands' following a command that creates multiple
1374 breakpoints affects all the breakpoints set by that command. This
1375 applies to breakpoints set by `rbreak', and also applies when a
1376 single `break' command creates multiple breakpoints (e.g.,
1377 breakpoints on overloaded c++ functions).
1379 * The `rbreak' command now accepts a filename specification as part of
1380 its argument, limiting the functions selected by the regex to those
1381 in the specified file.
1383 * Support for remote debugging Windows and SymbianOS shared libraries
1384 from Unix hosts has been improved. Non Windows GDB builds now can
1385 understand target reported file names that follow MS-DOS based file
1386 system semantics, such as file names that include drive letters and
1387 use the backslash character as directory separator. This makes it
1388 possible to transparently use the "set sysroot" and "set
1389 solib-search-path" on Unix hosts to point as host copies of the
1390 target's shared libraries. See the new command "set
1391 target-file-system-kind" described below, and the "Commands to
1392 specify files" section in the user manual for more information.
1396 eval template, expressions...
1397 Convert the values of one or more expressions under the control
1398 of the string template to a command line, and call it.
1400 set target-file-system-kind unix|dos-based|auto
1401 show target-file-system-kind
1402 Set or show the assumed file system kind for target reported file
1405 save breakpoints <filename>
1406 Save all current breakpoint definitions to a file suitable for use
1407 in a later debugging session. To read the saved breakpoint
1408 definitions, use the `source' command.
1410 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1413 info static-tracepoint-markers
1414 Display information about static tracepoint markers in the target.
1416 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1417 Define a static tracepoint by probing a marker at the given
1418 function, line, address, or marker ID.
1422 Enable and disable observer mode.
1424 set may-write-registers on|off
1425 set may-write-memory on|off
1426 set may-insert-breakpoints on|off
1427 set may-insert-tracepoints on|off
1428 set may-insert-fast-tracepoints on|off
1429 set may-interrupt on|off
1430 Set individual permissions for GDB effects on the target. Note that
1431 some of these settings can have undesirable or surprising
1432 consequences, particularly when changed in the middle of a session.
1433 For instance, disabling the writing of memory can prevent
1434 breakpoints from being inserted, cause single-stepping to fail, or
1435 even crash your program, if you disable after breakpoints have been
1436 inserted. However, GDB should not crash.
1438 set record memory-query on|off
1439 show record memory-query
1440 Control whether to stop the inferior if memory changes caused
1441 by an instruction cannot be recorded.
1446 The disassemble command now supports "start,+length" form of two arguments.
1450 ** GDB now provides a new directory location, called the python directory,
1451 where Python scripts written for GDB can be installed. The location
1452 of that directory is <data-directory>/python, where <data-directory>
1453 is the GDB data directory. For more details, see section `Scripting
1454 GDB using Python' in the manual.
1456 ** The GDB Python API now has access to breakpoints, symbols, symbol
1457 tables, program spaces, inferiors, threads and frame's code blocks.
1458 Additionally, GDB Parameters can now be created from the API, and
1459 manipulated via set/show in the CLI.
1461 ** New functions gdb.target_charset, gdb.target_wide_charset,
1462 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1464 ** New exception gdb.GdbError.
1466 ** Pretty-printers are now also looked up in the current program space.
1468 ** Pretty-printers can now be individually enabled and disabled.
1470 ** GDB now looks for names of Python scripts to auto-load in a
1471 special section named `.debug_gdb_scripts', in addition to looking
1472 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1474 * Tracepoint actions were unified with breakpoint commands. In particular,
1475 there are no longer differences in "info break" output for breakpoints and
1476 tracepoints and the "commands" command can be used for both tracepoints and
1477 regular breakpoints.
1481 ARM Symbian arm*-*-symbianelf*
1483 * D language support.
1484 GDB now supports debugging programs written in the D programming
1487 * GDB now supports the extended ptrace interface for PowerPC which is
1488 available since Linux kernel version 2.6.34. This automatically enables
1489 any hardware breakpoints and additional hardware watchpoints available in
1490 the processor. The old ptrace interface exposes just one hardware
1491 watchpoint and no hardware breakpoints.
1493 * GDB is now able to use the Data Value Compare (DVC) register available on
1494 embedded PowerPC processors to implement in hardware simple watchpoint
1495 conditions of the form:
1497 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1499 This works in native GDB running on Linux kernels with the extended ptrace
1500 interface mentioned above.
1502 *** Changes in GDB 7.1
1506 ** Namespace Support
1508 GDB now supports importing of namespaces in C++. This enables the
1509 user to inspect variables from imported namespaces. Support for
1510 namepace aliasing has also been added. So, if a namespace is
1511 aliased in the current scope (e.g. namepace C=A; ) the user can
1512 print variables using the alias (e.g. (gdb) print C::x).
1516 All known bugs relating to the printing of virtual base class were
1517 fixed. It is now possible to call overloaded static methods using a
1522 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1523 and reinterpret_cast<> are now handled by the C++ expression parser.
1527 Xilinx MicroBlaze microblaze-*-*
1532 Xilinx MicroBlaze microblaze
1535 * Multi-program debugging.
1537 GDB now has support for multi-program (a.k.a. multi-executable or
1538 multi-exec) debugging. This allows for debugging multiple inferiors
1539 simultaneously each running a different program under the same GDB
1540 session. See "Debugging Multiple Inferiors and Programs" in the
1541 manual for more information. This implied some user visible changes
1542 in the multi-inferior support. For example, "info inferiors" now
1543 lists inferiors that are not running yet or that have exited
1544 already. See also "New commands" and "New options" below.
1546 * New tracing features
1548 GDB's tracepoint facility now includes several new features:
1550 ** Trace state variables
1552 GDB tracepoints now include support for trace state variables, which
1553 are variables managed by the target agent during a tracing
1554 experiment. They are useful for tracepoints that trigger each
1555 other, so for instance one tracepoint can count hits in a variable,
1556 and then a second tracepoint has a condition that is true when the
1557 count reaches a particular value. Trace state variables share the
1558 $-syntax of GDB convenience variables, and can appear in both
1559 tracepoint actions and condition expressions. Use the "tvariable"
1560 command to create, and "info tvariables" to view; see "Trace State
1561 Variables" in the manual for more detail.
1565 GDB now includes an option for defining fast tracepoints, which
1566 targets may implement more efficiently, such as by installing a jump
1567 into the target agent rather than a trap instruction. The resulting
1568 speedup can be by two orders of magnitude or more, although the
1569 tradeoff is that some program locations on some target architectures
1570 might not allow fast tracepoint installation, for instance if the
1571 instruction to be replaced is shorter than the jump. To request a
1572 fast tracepoint, use the "ftrace" command, with syntax identical to
1573 the regular trace command.
1575 ** Disconnected tracing
1577 It is now possible to detach GDB from the target while it is running
1578 a trace experiment, then reconnect later to see how the experiment
1579 is going. In addition, a new variable disconnected-tracing lets you
1580 tell the target agent whether to continue running a trace if the
1581 connection is lost unexpectedly.
1585 GDB now has the ability to save the trace buffer into a file, and
1586 then use that file as a target, similarly to you can do with
1587 corefiles. You can select trace frames, print data that was
1588 collected in them, and use tstatus to display the state of the
1589 tracing run at the moment that it was saved. To create a trace
1590 file, use "tsave <filename>", and to use it, do "target tfile
1593 ** Circular trace buffer
1595 You can ask the target agent to handle the trace buffer as a
1596 circular buffer, discarding the oldest trace frames to make room for
1597 newer ones, by setting circular-trace-buffer to on. This feature may
1598 not be available for all target agents.
1603 The disassemble command, when invoked with two arguments, now requires
1604 the arguments to be comma-separated.
1607 The info variables command now displays variable definitions. Files
1608 which only declare a variable are not shown.
1611 The source command is now capable of sourcing Python scripts.
1612 This feature is dependent on the debugger being build with Python
1615 Related to this enhancement is also the introduction of a new command
1616 "set script-extension" (see below).
1618 * New commands (for set/show, see "New options" below)
1620 record save [<FILENAME>]
1621 Save a file (in core file format) containing the process record
1622 execution log for replay debugging at a later time.
1624 record restore <FILENAME>
1625 Restore the process record execution log that was saved at an
1626 earlier time, for replay debugging.
1628 add-inferior [-copies <N>] [-exec <FILENAME>]
1631 clone-inferior [-copies <N>] [ID]
1632 Make a new inferior ready to execute the same program another
1633 inferior has loaded.
1638 maint info program-spaces
1639 List the program spaces loaded into GDB.
1641 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1642 show remote interrupt-sequence
1643 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1644 as the sequence to the remote target in order to interrupt the execution.
1645 Ctrl-C is a default. Some system prefers BREAK which is high level of
1646 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1647 Magic SysRq g. It is BREAK signal and character 'g'.
1649 set remote interrupt-on-connect [on | off]
1650 show remote interrupt-on-connect
1651 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1652 remote target when gdb connects to it. This is needed when you debug
1655 set remotebreak [on | off]
1657 Deprecated. Use "set/show remote interrupt-sequence" instead.
1659 tvariable $NAME [ = EXP ]
1660 Create or modify a trace state variable.
1663 List trace state variables and their values.
1665 delete tvariable $NAME ...
1666 Delete one or more trace state variables.
1669 Evaluate the given expressions without collecting anything into the
1670 trace buffer. (Valid in tracepoint actions only.)
1672 ftrace FN / FILE:LINE / *ADDR
1673 Define a fast tracepoint at the given function, line, or address.
1675 * New expression syntax
1677 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1678 GDB now parses 0b101010 identically with 42.
1682 set follow-exec-mode new|same
1683 show follow-exec-mode
1684 Control whether GDB reuses the same inferior across an exec call or
1685 creates a new one. This is useful to be able to restart the old
1686 executable after the inferior having done an exec call.
1688 set default-collect EXPR, ...
1689 show default-collect
1690 Define a list of expressions to be collected at each tracepoint.
1691 This is a useful way to ensure essential items are not overlooked,
1692 such as registers or a critical global variable.
1694 set disconnected-tracing
1695 show disconnected-tracing
1696 If set to 1, the target is instructed to continue tracing if it
1697 loses its connection to GDB. If 0, the target is to stop tracing
1700 set circular-trace-buffer
1701 show circular-trace-buffer
1702 If set to on, the target is instructed to use a circular trace buffer
1703 and discard the oldest trace frames instead of stopping the trace due
1704 to a full trace buffer. If set to off, the trace stops when the buffer
1705 fills up. Some targets may not support this.
1707 set script-extension off|soft|strict
1708 show script-extension
1709 If set to "off", the debugger does not perform any script language
1710 recognition, and all sourced files are assumed to be GDB scripts.
1711 If set to "soft" (the default), files are sourced according to
1712 filename extension, falling back to GDB scripts if the first
1714 If set to "strict", files are sourced according to filename extension.
1716 set ada trust-PAD-over-XVS on|off
1717 show ada trust-PAD-over-XVS
1718 If off, activate a workaround against a bug in the debugging information
1719 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1720 the GCC sources for more information about the GNAT encoding and
1721 PAD types in particular). It is always safe to set this option to
1722 off, but this introduces a slight performance penalty. The default
1725 * Python API Improvements
1727 ** GDB provides the new class gdb.LazyString. This is useful in
1728 some pretty-printing cases. The new method gdb.Value.lazy_string
1729 provides a simple way to create objects of this type.
1731 ** The fields returned by gdb.Type.fields now have an
1732 `is_base_class' attribute.
1734 ** The new method gdb.Type.range returns the range of an array type.
1736 ** The new method gdb.parse_and_eval can be used to parse and
1737 evaluate an expression.
1739 * New remote packets
1742 Define a trace state variable.
1745 Get the current value of a trace state variable.
1748 Set desired tracing behavior upon disconnection.
1751 Set the trace buffer to be linear or circular.
1754 Get data about the tracepoints currently in use.
1758 Process record now works correctly with hardware watchpoints.
1760 Multiple bug fixes have been made to the mips-irix port, making it
1761 much more reliable. In particular:
1762 - Debugging threaded applications is now possible again. Previously,
1763 GDB would hang while starting the program, or while waiting for
1764 the program to stop at a breakpoint.
1765 - Attaching to a running process no longer hangs.
1766 - An error occurring while loading a core file has been fixed.
1767 - Changing the value of the PC register now works again. This fixes
1768 problems observed when using the "jump" command, or when calling
1769 a function from GDB, or even when assigning a new value to $pc.
1770 - With the "finish" and "return" commands, the return value for functions
1771 returning a small array is now correctly printed.
1772 - It is now possible to break on shared library code which gets executed
1773 during a shared library init phase (code executed while executing
1774 their .init section). Previously, the breakpoint would have no effect.
1775 - GDB is now able to backtrace through the signal handler for
1776 non-threaded programs.
1778 PIE (Position Independent Executable) programs debugging is now supported.
1779 This includes debugging execution of PIC (Position Independent Code) shared
1780 libraries although for that, it should be possible to run such libraries as an
1783 *** Changes in GDB 7.0
1785 * GDB now has an interface for JIT compilation. Applications that
1786 dynamically generate code can create symbol files in memory and register
1787 them with GDB. For users, the feature should work transparently, and
1788 for JIT developers, the interface is documented in the GDB manual in the
1789 "JIT Compilation Interface" chapter.
1791 * Tracepoints may now be conditional. The syntax is as for
1792 breakpoints; either an "if" clause appended to the "trace" command,
1793 or the "condition" command is available. GDB sends the condition to
1794 the target for evaluation using the same bytecode format as is used
1795 for tracepoint actions.
1797 * The disassemble command now supports: an optional /r modifier, print the
1798 raw instructions in hex as well as in symbolic form, and an optional /m
1799 modifier to print mixed source+assembly.
1801 * Process record and replay
1803 In a architecture environment that supports ``process record and
1804 replay'', ``process record and replay'' target can record a log of
1805 the process execution, and replay it with both forward and reverse
1808 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1809 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1810 set execution-direction {forward|reverse}, for targets that support
1813 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1814 feature is available with a native GDB running on kernel version
1817 * GDB now has support for multi-byte and wide character sets on the
1818 target. Strings whose character type is wchar_t, char16_t, or
1819 char32_t are now correctly printed. GDB supports wide- and unicode-
1820 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1821 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1822 `printf'. This feature requires iconv to work properly; if your
1823 system does not have a working iconv, GDB can use GNU libiconv. See
1824 the installation instructions for more information.
1826 * GDB now supports automatic retrieval of shared library files from
1827 remote targets. To use this feature, specify a system root that begins
1828 with the `remote:' prefix, either via the `set sysroot' command or via
1829 the `--with-sysroot' configure-time option.
1831 * "info sharedlibrary" now takes an optional regex of libraries to show,
1832 and it now reports if a shared library has no debugging information.
1834 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1835 now complete on file names.
1837 * When completing in expressions, gdb will attempt to limit
1838 completions to allowable structure or union fields, where appropriate.
1839 For instance, consider:
1841 # struct example { int f1; double f2; };
1842 # struct example variable;
1845 If the user types TAB at the end of this command line, the available
1846 completions will be "f1" and "f2".
1848 * Inlined functions are now supported. They show up in backtraces, and
1849 the "step", "next", and "finish" commands handle them automatically.
1851 * GDB now supports the token-splicing (##) and stringification (#)
1852 operators when expanding macros. It also supports variable-arity
1855 * GDB now supports inspecting extra signal information, exported by
1856 the new $_siginfo convenience variable. The feature is currently
1857 implemented on linux ARM, i386 and amd64.
1859 * GDB can now display the VFP floating point registers and NEON vector
1860 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1861 can provide these registers (requires Linux 2.6.30 or later). Remote
1862 and simulator targets may also provide them.
1864 * New remote packets
1867 Search memory for a sequence of bytes.
1870 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1871 operation over reliable transport links. Use of this packet is
1872 controlled by the `set remote noack-packet' command.
1875 Kill the process with the specified process ID. Use this in preference
1876 to `k' when multiprocess protocol extensions are supported.
1879 Obtains additional operating system information
1883 Read or write additional signal information.
1885 * Removed remote protocol undocumented extension
1887 An undocumented extension to the remote protocol's `S' stop reply
1888 packet that permited the stub to pass a process id was removed.
1889 Remote servers should use the `T' stop reply packet instead.
1891 * GDB now supports multiple function calling conventions according to the
1892 DWARF-2 DW_AT_calling_convention function attribute.
1894 * The SH target utilizes the aforementioned change to distinguish between gcc
1895 and Renesas calling convention. It also adds the new CLI commands
1896 `set/show sh calling-convention'.
1898 * GDB can now read compressed debug sections, as produced by GNU gold
1899 with the --compress-debug-sections=zlib flag.
1901 * 64-bit core files are now supported on AIX.
1903 * Thread switching is now supported on Tru64.
1905 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1906 which will be allocated using malloc later in program execution.
1908 * The qXfer:libraries:read remote procotol packet now allows passing a
1909 list of section offsets.
1911 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1912 conditions handling signals delivered during attach or thread creation
1913 have also been fixed.
1915 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1916 From the user's standpoint, all unqualified instances of True and False
1917 are treated as the standard definitions, regardless of context.
1919 * GDB now parses C++ symbol and type names more flexibly. For
1922 template<typename T> class C { };
1925 GDB will now correctly handle all of:
1927 ptype C<char const *>
1928 ptype C<char const*>
1929 ptype C<const char *>
1930 ptype C<const char*>
1932 * New features in the GDB remote stub, gdbserver
1934 - The "--wrapper" command-line argument tells gdbserver to use a
1935 wrapper program to launch programs for debugging.
1937 - On PowerPC and S/390 targets, it is now possible to use a single
1938 gdbserver executable to debug both 32-bit and 64-bit programs.
1939 (This requires gdbserver itself to be built as a 64-bit executable.)
1941 - gdbserver uses the new noack protocol mode for TCP connections to
1942 reduce communications latency, if also supported and enabled in GDB.
1944 - Support for the sparc64-linux-gnu target is now included in
1947 - The amd64-linux build of gdbserver now supports debugging both
1948 32-bit and 64-bit programs.
1950 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1951 now support hardware watchpoints, and will use them automatically
1956 GDB now has support for scripting using Python. Whether this is
1957 available is determined at configure time.
1959 New GDB commands can now be written in Python.
1961 * Ada tasking support
1963 Ada tasks can now be inspected in GDB. The following commands have
1967 Print the list of Ada tasks.
1969 Print detailed information about task number N.
1971 Print the task number of the current task.
1973 Switch the context of debugging to task number N.
1975 * Support for user-defined prefixed commands. The "define" command can
1976 add new commands to existing prefixes, e.g. "target".
1978 * Multi-inferior, multi-process debugging.
1980 GDB now has generalized support for multi-inferior debugging. See
1981 "Debugging Multiple Inferiors" in the manual for more information.
1982 Although availability still depends on target support, the command
1983 set is more uniform now. The GNU/Linux specific multi-forks support
1984 has been migrated to this new framework. This implied some user
1985 visible changes; see "New commands" and also "Removed commands"
1988 * Target descriptions can now describe the target OS ABI. See the
1989 "Target Description Format" section in the user manual for more
1992 * Target descriptions can now describe "compatible" architectures
1993 to indicate that the target can execute applications for a different
1994 architecture in addition to those for the main target architecture.
1995 See the "Target Description Format" section in the user manual for
1998 * Multi-architecture debugging.
2000 GDB now includes general supports for debugging applications on
2001 hybrid systems that use more than one single processor architecture
2002 at the same time. Each such hybrid architecture still requires
2003 specific support to be added. The only hybrid architecture supported
2004 in this version of GDB is the Cell Broadband Engine.
2006 * GDB now supports integrated debugging of Cell/B.E. applications that
2007 use both the PPU and SPU architectures. To enable support for hybrid
2008 Cell/B.E. debugging, you need to configure GDB to support both the
2009 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
2010 --enable-targets configure option.
2012 * Non-stop mode debugging.
2014 For some targets, GDB now supports an optional mode of operation in
2015 which you can examine stopped threads while other threads continue
2016 to execute freely. This is referred to as non-stop mode, with the
2017 old mode referred to as all-stop mode. See the "Non-Stop Mode"
2018 section in the user manual for more information.
2020 To be able to support remote non-stop debugging, a remote stub needs
2021 to implement the non-stop mode remote protocol extensions, as
2022 described in the "Remote Non-Stop" section of the user manual. The
2023 GDB remote stub, gdbserver, has been adjusted to support these
2024 extensions on linux targets.
2026 * New commands (for set/show, see "New options" below)
2028 catch syscall [NAME(S) | NUMBER(S)]
2029 Catch system calls. Arguments, which should be names of system
2030 calls or their numbers, mean catch only those syscalls. Without
2031 arguments, every syscall will be caught. When the inferior issues
2032 any of the specified syscalls, GDB will stop and announce the system
2033 call, both when it is called and when its call returns. This
2034 feature is currently available with a native GDB running on the
2035 Linux Kernel, under the following architectures: x86, x86_64,
2036 PowerPC and PowerPC64.
2038 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
2040 Search memory for a sequence of bytes.
2042 maint set python print-stack
2043 maint show python print-stack
2044 Show a stack trace when an error is encountered in a Python script.
2047 Invoke CODE by passing it to the Python interpreter.
2052 These allow macros to be defined, undefined, and listed
2056 Show operating system information about processes.
2059 List the inferiors currently under GDB's control.
2062 Switch focus to inferior number NUM.
2065 Detach from inferior number NUM.
2068 Kill inferior number NUM.
2072 set spu stop-on-load
2073 show spu stop-on-load
2074 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2076 set spu auto-flush-cache
2077 show spu auto-flush-cache
2078 Control whether to automatically flush the software-managed cache
2079 during Cell/B.E. debugging.
2081 set sh calling-convention
2082 show sh calling-convention
2083 Control the calling convention used when calling SH target functions.
2086 show debug timestamp
2087 Control display of timestamps with GDB debugging output.
2089 set disassemble-next-line
2090 show disassemble-next-line
2091 Control display of disassembled source lines or instructions when
2094 set remote noack-packet
2095 show remote noack-packet
2096 Set/show the use of remote protocol QStartNoAckMode packet. See above
2097 under "New remote packets."
2099 set remote query-attached-packet
2100 show remote query-attached-packet
2101 Control use of remote protocol `qAttached' (query-attached) packet.
2103 set remote read-siginfo-object
2104 show remote read-siginfo-object
2105 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2108 set remote write-siginfo-object
2109 show remote write-siginfo-object
2110 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2113 set remote reverse-continue
2114 show remote reverse-continue
2115 Control use of remote protocol 'bc' (reverse-continue) packet.
2117 set remote reverse-step
2118 show remote reverse-step
2119 Control use of remote protocol 'bs' (reverse-step) packet.
2121 set displaced-stepping
2122 show displaced-stepping
2123 Control displaced stepping mode. Displaced stepping is a way to
2124 single-step over breakpoints without removing them from the debuggee.
2125 Also known as "out-of-line single-stepping".
2128 show debug displaced
2129 Control display of debugging info for displaced stepping.
2131 maint set internal-error
2132 maint show internal-error
2133 Control what GDB does when an internal error is detected.
2135 maint set internal-warning
2136 maint show internal-warning
2137 Control what GDB does when an internal warning is detected.
2142 Use a wrapper program to launch programs for debugging.
2144 set multiple-symbols (all|ask|cancel)
2145 show multiple-symbols
2146 The value of this variable can be changed to adjust the debugger behavior
2147 when an expression or a breakpoint location contains an ambiguous symbol
2148 name (an overloaded function name, for instance).
2150 set breakpoint always-inserted
2151 show breakpoint always-inserted
2152 Keep breakpoints always inserted in the target, as opposed to inserting
2153 them when resuming the target, and removing them when the target stops.
2154 This option can improve debugger performance on slow remote targets.
2156 set arm fallback-mode (arm|thumb|auto)
2157 show arm fallback-mode
2158 set arm force-mode (arm|thumb|auto)
2160 These commands control how ARM GDB determines whether instructions
2161 are ARM or Thumb. The default for both settings is auto, which uses
2162 the current CPSR value for instructions without symbols; previous
2163 versions of GDB behaved as if "set arm fallback-mode arm".
2165 set disable-randomization
2166 show disable-randomization
2167 Standalone programs run with the virtual address space randomization enabled
2168 by default on some platforms. This option keeps the addresses stable across
2169 multiple debugging sessions.
2173 Control whether other threads are stopped or not when some thread hits
2178 Requests that asynchronous execution is enabled in the target, if available.
2179 In this case, it's possible to resume target in the background, and interact
2180 with GDB while the target is running. "show target-async" displays the
2181 current state of asynchronous execution of the target.
2183 set target-wide-charset
2184 show target-wide-charset
2185 The target-wide-charset is the name of the character set that GDB
2186 uses when printing characters whose type is wchar_t.
2188 set tcp auto-retry (on|off)
2190 set tcp connect-timeout
2191 show tcp connect-timeout
2192 These commands allow GDB to retry failed TCP connections to a remote stub
2193 with a specified timeout period; this is useful if the stub is launched
2194 in parallel with GDB but may not be ready to accept connections immediately.
2196 set libthread-db-search-path
2197 show libthread-db-search-path
2198 Control list of directories which GDB will search for appropriate
2201 set schedule-multiple (on|off)
2202 show schedule-multiple
2203 Allow GDB to resume all threads of all processes or only threads of
2204 the current process.
2208 Use more aggressive caching for accesses to the stack. This improves
2209 performance of remote debugging (particularly backtraces) without
2210 affecting correctness.
2212 set interactive-mode (on|off|auto)
2213 show interactive-mode
2214 Control whether GDB runs in interactive mode (on) or not (off).
2215 When in interactive mode, GDB waits for the user to answer all
2216 queries. Otherwise, GDB does not wait and assumes the default
2217 answer. When set to auto (the default), GDB determines which
2218 mode to use based on the stdin settings.
2223 For program forks, this is replaced by the new more generic `info
2224 inferiors' command. To list checkpoints, you can still use the
2225 `info checkpoints' command, which was an alias for the `info forks'
2229 Replaced by the new `inferior' command. To switch between
2230 checkpoints, you can still use the `restart' command, which was an
2231 alias for the `fork' command.
2234 This is removed, since some targets don't have a notion of
2235 processes. To switch between processes, you can still use the
2236 `inferior' command using GDB's own inferior number.
2239 For program forks, this is replaced by the new more generic `kill
2240 inferior' command. To delete a checkpoint, you can still use the
2241 `delete checkpoint' command, which was an alias for the `delete
2245 For program forks, this is replaced by the new more generic `detach
2246 inferior' command. To detach a checkpoint, you can still use the
2247 `detach checkpoint' command, which was an alias for the `detach
2250 * New native configurations
2252 x86/x86_64 Darwin i[34567]86-*-darwin*
2254 x86_64 MinGW x86_64-*-mingw*
2258 Lattice Mico32 lm32-*
2259 x86 DICOS i[34567]86-*-dicos*
2260 x86_64 DICOS x86_64-*-dicos*
2263 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2264 (mingw32ce) debugging.
2270 These commands were actually not implemented on any target.
2272 *** Changes in GDB 6.8
2274 * New native configurations
2276 NetBSD/hppa hppa*-*netbsd*
2277 Xtensa GNU/Linux xtensa*-*-linux*
2281 NetBSD/hppa hppa*-*-netbsd*
2282 Xtensa GNU/Lunux xtensa*-*-linux*
2284 * Change in command line behavior -- corefiles vs. process ids.
2286 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2287 attaching to process NUMBER fails, GDB no longer attempts to open a
2288 core file named NUMBER. Attaching to a program using the -c option
2289 is no longer supported. Instead, use the '-p' or '--pid' options.
2291 * GDB can now be built as a native debugger for debugging Windows x86
2292 (mingw32) Portable Executable (PE) programs.
2294 * Pending breakpoints no longer change their number when their address
2297 * GDB now supports breakpoints with multiple locations,
2298 including breakpoints on C++ constructors, inside C++ templates,
2299 and in inlined functions.
2301 * GDB's ability to debug optimized code has been improved. GDB more
2302 accurately identifies function bodies and lexical blocks that occupy
2303 more than one contiguous range of addresses.
2305 * Target descriptions can now describe registers for PowerPC.
2307 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2308 registers on PowerPC targets.
2310 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2311 targets even when the libthread_db library is not available.
2313 * The GDB remote stub, gdbserver, now supports the new file transfer
2314 commands (remote put, remote get, and remote delete).
2316 * The GDB remote stub, gdbserver, now supports run and attach in
2317 extended-remote mode.
2319 * hppa*64*-*-hpux11* target broken
2320 The debugger is unable to start a program and fails with the following
2321 error: "Error trying to get information about dynamic linker".
2322 The gdb-6.7 release is also affected.
2324 * GDB now supports the --enable-targets= configure option to allow
2325 building a single GDB executable that supports multiple remote
2326 target architectures.
2328 * GDB now supports debugging C and C++ programs which use the
2329 Decimal Floating Point extension. In addition, the PowerPC target
2330 now has a set of pseudo-registers to inspect decimal float values
2331 stored in two consecutive float registers.
2333 * The -break-insert MI command can optionally create pending
2336 * Improved support for debugging Ada
2337 Many improvements to the Ada language support have been made. These
2339 - Better support for Ada2005 interface types
2340 - Improved handling of arrays and slices in general
2341 - Better support for Taft-amendment types
2342 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2344 - Improved command completion in Ada
2347 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2352 set print frame-arguments (all|scalars|none)
2353 show print frame-arguments
2354 The value of this variable can be changed to control which argument
2355 values should be printed by the debugger when displaying a frame.
2360 Transfer files to and from a remote target, and delete remote files.
2367 Transfer files to and from a remote target, and delete remote files.
2369 * New remote packets
2376 Open, close, read, write, and delete files on the remote system.
2379 Attach to an existing process on the remote system, in extended-remote
2383 Run a new process on the remote system, in extended-remote mode.
2385 *** Changes in GDB 6.7
2387 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2388 bfd, libiberty and opcodes, as revealed by static analysis donated by
2389 Coverity, Inc. (http://scan.coverity.com).
2391 * When looking up multiply-defined global symbols, GDB will now prefer the
2392 symbol definition in the current shared library if it was built using the
2393 -Bsymbolic linker option.
2395 * When the Text User Interface (TUI) is not configured, GDB will now
2396 recognize the -tui command-line option and print a message that the TUI
2399 * The GDB remote stub, gdbserver, now has lower overhead for high
2400 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2402 * GDB for MIPS targets now autodetects whether a remote target provides
2403 32-bit or 64-bit register values.
2405 * Support for C++ member pointers has been improved.
2407 * GDB now understands XML target descriptions, which specify the
2408 target's overall architecture. GDB can read a description from
2409 a local file or over the remote serial protocol.
2411 * Vectors of single-byte data use a new integer type which is not
2412 automatically displayed as character or string data.
2414 * The /s format now works with the print command. It displays
2415 arrays of single-byte integers and pointers to single-byte integers
2418 * Target descriptions can now describe target-specific registers,
2419 for architectures which have implemented the support (currently
2420 only ARM, M68K, and MIPS).
2422 * GDB and the GDB remote stub, gdbserver, now support the XScale
2425 * The GDB remote stub, gdbserver, has been updated to support
2426 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2427 has been rewritten to use the standard GDB remote protocol.
2429 * GDB can now step into C++ functions which are called through thunks.
2431 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2433 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2434 layout. It also supports a TextSeg= and DataSeg= response when only
2435 segment base addresses (rather than offsets) are available.
2437 * The /i format now outputs any trailing branch delay slot instructions
2438 immediately following the last instruction within the count specified.
2440 * The GDB remote protocol "T" stop reply packet now supports a
2441 "library" response. Combined with the new "qXfer:libraries:read"
2442 packet, this response allows GDB to debug shared libraries on targets
2443 where the operating system manages the list of loaded libraries (e.g.
2444 Windows and SymbianOS).
2446 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2447 (DLLs) on Windows and Windows CE targets.
2449 * GDB now supports a faster verification that a .debug file matches its binary
2450 according to its build-id signature, if the signature is present.
2456 Enable or disable hardware flow control (RTS/CTS) on the serial port
2457 when debugging using remote targets.
2459 set mem inaccessible-by-default
2460 show mem inaccessible-by-default
2461 If the target supplies a memory map, for instance via the remote
2462 protocol's "qXfer:memory-map:read" packet, setting this variable
2463 prevents GDB from accessing memory outside the memory map. This
2464 is useful for targets with memory mapped registers or which react
2465 badly to accesses of unmapped address space.
2467 set breakpoint auto-hw
2468 show breakpoint auto-hw
2469 If the target supplies a memory map, for instance via the remote
2470 protocol's "qXfer:memory-map:read" packet, setting this variable
2471 lets GDB use hardware breakpoints automatically for memory regions
2472 where it can not use software breakpoints. This covers both the
2473 "break" command and internal breakpoints used for other commands
2474 including "next" and "finish".
2477 catch exception unhandled
2478 Stop the program execution when Ada exceptions are raised.
2481 Stop the program execution when an Ada assertion failed.
2485 Set an alternate system root for target files. This is a more
2486 general version of "set solib-absolute-prefix", which is now
2487 an alias to "set sysroot".
2490 Provide extended SPU facility status information. This set of
2491 commands is available only when debugging the Cell/B.E. SPU
2494 * New native configurations
2496 OpenBSD/sh sh*-*openbsd*
2499 unset tdesc filename
2501 Use the specified local file as an XML target description, and do
2502 not query the target for its built-in description.
2506 OpenBSD/sh sh*-*-openbsd*
2507 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2508 Toshiba Media Processor mep-elf
2510 * New remote packets
2513 Ignore the specified signals; pass them directly to the debugged program
2514 without stopping other threads or reporting them to GDB.
2516 qXfer:features:read:
2517 Read an XML target description from the target, which describes its
2522 Read or write contents of an spufs file on the target system. These
2523 packets are available only on the Cell/B.E. SPU architecture.
2525 qXfer:libraries:read:
2526 Report the loaded shared libraries. Combined with new "T" packet
2527 response, this packet allows GDB to debug shared libraries on
2528 targets where the operating system manages the list of loaded
2529 libraries (e.g. Windows and SymbianOS).
2533 Support for these obsolete configurations has been removed.
2541 i[34567]86-*-lynxos*
2542 i[34567]86-*-netware*
2543 i[34567]86-*-sco3.2v5*
2544 i[34567]86-*-sco3.2v4*
2546 i[34567]86-*-sysv4.2*
2549 i[34567]86-*-unixware2*
2550 i[34567]86-*-unixware*
2559 * Other removed features
2566 Various m68k-only ROM monitors.
2573 Various Renesas ROM monitors and debugging interfaces for SH and
2578 Support for a Macraigor serial interface to on-chip debugging.
2579 GDB does not directly support the newer parallel or USB
2584 A debug information format. The predecessor to DWARF 2 and
2585 DWARF 3, which are still supported.
2587 Support for the HP aCC compiler on HP-UX/PA-RISC
2589 SOM-encapsulated symbolic debugging information, automatic
2590 invocation of pxdb, and the aCC custom C++ ABI. This does not
2591 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2592 with aCC can still be debugged on an assembly level.
2594 MIPS ".pdr" sections
2596 A MIPS-specific format used to describe stack frame layout
2597 in debugging information.
2601 GDB could work with an older version of Guile to debug
2602 the interpreter and Scheme programs running in it.
2604 set mips stack-arg-size
2605 set mips saved-gpreg-size
2607 Use "set mips abi" to control parameter passing for MIPS.
2609 *** Changes in GDB 6.6
2614 Cell Broadband Engine SPU spu-elf
2616 * GDB can now be configured as a cross-debugger targeting native Windows
2617 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2618 running on a Windows system over TCP/IP to debug Windows programs.
2620 * The GDB remote stub, gdbserver, has been updated to support Windows and
2621 Cygwin debugging. Both single-threaded and multi-threaded programs are
2624 * The "set trust-readonly-sections" command works again. This command was
2625 broken in GDB 6.3, 6.4, and 6.5.
2627 * The "load" command now supports writing to flash memory, if the remote
2628 stub provides the required support.
2630 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2631 longer requires symbolic debug information (e.g. DWARF-2).
2636 unset substitute-path
2637 show substitute-path
2638 Manage a list of substitution rules that GDB uses to rewrite the name
2639 of the directories where the sources are located. This can be useful
2640 for instance when the sources were moved to a different location
2641 between compilation and debugging.
2645 Print each CLI command as it is executed. Each command is prefixed with
2646 a number of `+' symbols representing the nesting depth.
2647 The source command now has a `-v' option to enable the same feature.
2651 The ARM Demon monitor support (RDP protocol, "target rdp").
2653 Kernel Object Display, an embedded debugging feature which only worked with
2654 an obsolete version of Cisco IOS.
2656 The 'set download-write-size' and 'show download-write-size' commands.
2658 * New remote packets
2661 Tell a stub about GDB client features, and request remote target features.
2662 The first feature implemented is PacketSize, which allows the target to
2663 specify the size of packets it can handle - to minimize the number of
2664 packets required and improve performance when connected to a remote
2668 Fetch an OS auxilliary vector from the remote stub. This packet is a
2669 more efficient replacement for qPart:auxv:read.
2671 qXfer:memory-map:read:
2672 Fetch a memory map from the remote stub, including information about
2673 RAM, ROM, and flash memory devices.
2678 Erase and program a flash memory device.
2680 * Removed remote packets
2683 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2684 used it, and only gdbserver implemented it.
2686 *** Changes in GDB 6.5
2690 Renesas M32C/M16C m32c-elf
2692 Morpho Technologies ms1 ms1-elf
2696 init-if-undefined Initialize a convenience variable, but
2697 only if it doesn't already have a value.
2699 The following commands are presently only implemented for native GNU/Linux:
2701 checkpoint Save a snapshot of the program state.
2703 restart <n> Return the program state to a
2704 previously saved state.
2706 info checkpoints List currently saved checkpoints.
2708 delete-checkpoint <n> Delete a previously saved checkpoint.
2710 set|show detach-on-fork Tell gdb whether to detach from a newly
2711 forked process, or to keep debugging it.
2713 info forks List forks of the user program that
2714 are available to be debugged.
2716 fork <n> Switch to debugging one of several
2717 forks of the user program that are
2718 available to be debugged.
2720 delete-fork <n> Delete a fork from the list of forks
2721 that are available to be debugged (and
2722 kill the forked process).
2724 detach-fork <n> Delete a fork from the list of forks
2725 that are available to be debugged (and
2726 allow the process to continue).
2730 Morpho Technologies ms2 ms1-elf
2732 * Improved Windows host support
2734 GDB now builds as a cross debugger hosted on i686-mingw32, including
2735 native console support, and remote communications using either
2736 network sockets or serial ports.
2738 * Improved Modula-2 language support
2740 GDB can now print most types in the Modula-2 syntax. This includes:
2741 basic types, set types, record types, enumerated types, range types,
2742 pointer types and ARRAY types. Procedure var parameters are correctly
2743 printed and hexadecimal addresses and character constants are also
2744 written in the Modula-2 syntax. Best results can be obtained by using
2745 GNU Modula-2 together with the -gdwarf-2 command line option.
2749 The ARM rdi-share module.
2751 The Netware NLM debug server.
2753 *** Changes in GDB 6.4
2755 * New native configurations
2757 OpenBSD/arm arm*-*-openbsd*
2758 OpenBSD/mips64 mips64-*-openbsd*
2762 Morpho Technologies ms1 ms1-elf
2764 * New command line options
2766 --batch-silent As for --batch, but totally silent.
2767 --return-child-result The debugger will exist with the same value
2768 the child (debugged) program exited with.
2769 --eval-command COMMAND, -ex COMMAND
2770 Execute a single GDB CLI command. This may be
2771 specified multiple times and in conjunction
2772 with the --command (-x) option.
2774 * Deprecated commands removed
2776 The following commands, that were deprecated in 2000, have been
2780 set|show arm disassembly-flavor set|show arm disassembler
2781 othernames set arm disassembler
2782 set|show remotedebug set|show debug remote
2783 set|show archdebug set|show debug arch
2784 set|show eventdebug set|show debug event
2787 * New BSD user-level threads support
2789 It is now possible to debug programs using the user-level threads
2790 library on OpenBSD and FreeBSD. Currently supported (target)
2793 FreeBSD/amd64 x86_64-*-freebsd*
2794 FreeBSD/i386 i386-*-freebsd*
2795 OpenBSD/i386 i386-*-openbsd*
2797 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2798 are not yet supported.
2800 * New support for Matsushita MN10300 w/sim added
2801 (Work in progress). mn10300-elf.
2803 * REMOVED configurations and files
2805 VxWorks and the XDR protocol *-*-vxworks
2806 Motorola MCORE mcore-*-*
2807 National Semiconductor NS32000 ns32k-*-*
2809 * New "set print array-indexes" command
2811 After turning this setting "on", GDB prints the index of each element
2812 when displaying arrays. The default is "off" to preserve the previous
2815 * VAX floating point support
2817 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2819 * User-defined command support
2821 In addition to using $arg0..$arg9 for argument passing, it is now possible
2822 to use $argc to determine now many arguments have been passed. See the
2823 section on user-defined commands in the user manual for more information.
2825 *** Changes in GDB 6.3:
2827 * New command line option
2829 GDB now accepts -l followed by a number to set the timeout for remote
2832 * GDB works with GCC -feliminate-dwarf2-dups
2834 GDB now supports a more compact representation of DWARF-2 debug
2835 information using DW_FORM_ref_addr references. These are produced
2836 by GCC with the option -feliminate-dwarf2-dups and also by some
2837 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2838 to use -feliminate-dwarf2-dups.
2840 * Internationalization
2842 When supported by the host system, GDB will be built with
2843 internationalization (libintl). The task of marking up the sources is
2844 continued, we're looking forward to our first translation.
2848 Initial support for debugging programs compiled with the GNAT
2849 implementation of the Ada programming language has been integrated
2850 into GDB. In this release, support is limited to expression evaluation.
2852 * New native configurations
2854 GNU/Linux/m32r m32r-*-linux-gnu
2858 GDB's remote protocol now includes support for the 'p' packet. This
2859 packet is used to fetch individual registers from a remote inferior.
2861 * END-OF-LIFE registers[] compatibility module
2863 GDB's internal register infrastructure has been completely rewritten.
2864 The new infrastructure making possible the implementation of key new
2865 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2868 GDB 6.3 will be the last release to include the the registers[]
2869 compatibility module that allowed out-of-date configurations to
2870 continue to work. This change directly impacts the following
2880 powerpc bdm protocol
2882 Unless there is activity to revive these configurations, they will be
2883 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2885 * OBSOLETE configurations and files
2887 Configurations that have been declared obsolete in this release have
2888 been commented out. Unless there is activity to revive these
2889 configurations, the next release of GDB will have their sources
2890 permanently REMOVED.
2899 *** Changes in GDB 6.2.1:
2901 * MIPS `break main; run' gave an heuristic-fence-post warning
2903 When attempting to run even a simple program, a warning about
2904 heuristic-fence-post being hit would be reported. This problem has
2907 * MIPS IRIX 'long double' crashed GDB
2909 When examining a long double variable, GDB would get a segmentation
2910 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2911 IRIX long double values).
2915 A bug in the VAX stack code was causing problems with the "next"
2916 command. This problem has been fixed.
2918 *** Changes in GDB 6.2:
2920 * Fix for ``many threads''
2922 On GNU/Linux systems that use the NPTL threads library, a program
2923 rapidly creating and deleting threads would confuse GDB leading to the
2926 ptrace: No such process.
2927 thread_db_get_info: cannot get thread info: generic error
2929 This problem has been fixed.
2931 * "-async" and "-noasync" options removed.
2933 Support for the broken "-noasync" option has been removed (it caused
2936 * New ``start'' command.
2938 This command runs the program until the begining of the main procedure.
2940 * New BSD Kernel Data Access Library (libkvm) interface
2942 Using ``target kvm'' it is now possible to debug kernel core dumps and
2943 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2944 platforms. Currently supported (native-only) configurations are:
2946 FreeBSD/amd64 x86_64-*-freebsd*
2947 FreeBSD/i386 i?86-*-freebsd*
2948 NetBSD/i386 i?86-*-netbsd*
2949 NetBSD/m68k m68*-*-netbsd*
2950 NetBSD/sparc sparc-*-netbsd*
2951 OpenBSD/amd64 x86_64-*-openbsd*
2952 OpenBSD/i386 i?86-*-openbsd*
2953 OpenBSD/m68k m68*-openbsd*
2954 OpenBSD/sparc sparc-*-openbsd*
2956 * Signal trampoline code overhauled
2958 Many generic problems with GDB's signal handling code have been fixed.
2959 These include: backtraces through non-contiguous stacks; recognition
2960 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2961 call; backtrace through a signal trampoline; step into and out of
2962 signal handlers; and single-stepping in the signal trampoline.
2964 Please note that kernel bugs are a limiting factor here. These
2965 features have been shown to work on an s390 GNU/Linux system that
2966 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2968 * Cygwin support for DWARF 2 added.
2970 * New native configurations
2972 GNU/Linux/hppa hppa*-*-linux*
2973 OpenBSD/hppa hppa*-*-openbsd*
2974 OpenBSD/m68k m68*-*-openbsd*
2975 OpenBSD/m88k m88*-*-openbsd*
2976 OpenBSD/powerpc powerpc-*-openbsd*
2977 NetBSD/vax vax-*-netbsd*
2978 OpenBSD/vax vax-*-openbsd*
2980 * END-OF-LIFE frame compatibility module
2982 GDB's internal frame infrastructure has been completely rewritten.
2983 The new infrastructure making it possible to support key new features
2984 including DWARF 2 Call Frame Information. To aid in the task of
2985 migrating old configurations to this new infrastructure, a
2986 compatibility module, that allowed old configurations to continue to
2987 work, was also included.
2989 GDB 6.2 will be the last release to include this frame compatibility
2990 module. This change directly impacts the following configurations:
3000 Unless there is activity to revive these configurations, they will be
3001 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
3003 * REMOVED configurations and files
3005 Sun 3, running SunOS 3 m68*-*-sunos3*
3006 Sun 3, running SunOS 4 m68*-*-sunos4*
3007 Sun 2, running SunOS 3 m68000-*-sunos3*
3008 Sun 2, running SunOS 4 m68000-*-sunos4*
3009 Motorola 680x0 running LynxOS m68*-*-lynxos*
3010 AT&T 3b1/Unix pc m68*-att-*
3011 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3012 decstation mips-dec-* mips-little-*
3013 riscos mips-*-riscos* mips-*-sysv*
3014 sonymips mips-sony-*
3015 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3017 *** Changes in GDB 6.1.1:
3019 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
3021 The TUI (Text-mode User Interface) is now built as part of a default
3022 GDB configuration. It is enabled by either selecting the TUI with the
3023 command line option "-i=tui" or by running the separate "gdbtui"
3024 program. For more information on the TUI, see the manual "Debugging
3027 * Pending breakpoint support (also included in GDB 6.1)
3029 Support has been added to allow you to specify breakpoints in shared
3030 libraries that have not yet been loaded. If a breakpoint location
3031 cannot be found, and the "breakpoint pending" option is set to auto,
3032 GDB queries you if you wish to make the breakpoint pending on a future
3033 shared-library load. If and when GDB resolves the breakpoint symbol,
3034 the pending breakpoint is removed as one or more regular breakpoints
3037 Pending breakpoints are very useful for GCJ Java debugging.
3039 * Fixed ISO-C build problems
3041 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
3042 non ISO-C code that stopped them being built using a more strict ISO-C
3043 compiler (e.g., IBM's C compiler).
3045 * Fixed build problem on IRIX 5
3047 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
3048 wasn't able to compile compile on an IRIX 5 system.
3050 * Added execute permission to gdb/gdbserver/configure
3052 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3053 permission. This bug would cause configure to fail on a number of
3054 systems (Solaris, IRIX). Ref: server/519.
3056 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3058 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3059 has been updated to use constant array sizes.
3061 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3063 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3064 its generated DWARF Call Frame Info. This encoding was causing GDB to
3065 panic, that panic has been fixed. Ref: gdb/1628.
3067 * Fixed a problem when examining parameters in shared library code.
3069 When examining parameters in optimized shared library code generated
3070 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3071 not available''. GDB now correctly displays the variable's value.
3073 *** Changes in GDB 6.1:
3075 * Removed --with-mmalloc
3077 Support for the mmalloc memory manager has been removed, as it
3078 conflicted with the internal gdb byte cache.
3080 * Changes in AMD64 configurations
3082 The AMD64 target now includes the %cs and %ss registers. As a result
3083 the AMD64 remote protocol has changed; this affects the floating-point
3084 and SSE registers. If you rely on those registers for your debugging,
3085 you should upgrade gdbserver on the remote side.
3087 * Revised SPARC target
3089 The SPARC target has been completely revised, incorporating the
3090 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3091 support for LynxOS and SunOS 4 has been dropped. Calling functions
3092 from within GDB on operating systems with a non-executable stack
3093 (Solaris, OpenBSD) now works.
3097 GDB has a new C++ demangler which does a better job on the mangled
3098 names generated by current versions of g++. It also runs faster, so
3099 with this and other changes gdb should now start faster on large C++
3102 * DWARF 2 Location Expressions
3104 GDB support for location expressions has been extended to support function
3105 arguments and frame bases. Older versions of GDB could crash when they
3108 * C++ nested types and namespaces
3110 GDB's support for nested types and namespaces in C++ has been
3111 improved, especially if you use the DWARF 2 debugging format. (This
3112 is the default for recent versions of GCC on most platforms.)
3113 Specifically, if you have a class "Inner" defined within a class or
3114 namespace "Outer", then GDB realizes that the class's name is
3115 "Outer::Inner", not simply "Inner". This should greatly reduce the
3116 frequency of complaints about not finding RTTI symbols. In addition,
3117 if you are stopped at inside of a function defined within a namespace,
3118 GDB modifies its name lookup accordingly.
3120 * New native configurations
3122 NetBSD/amd64 x86_64-*-netbsd*
3123 OpenBSD/amd64 x86_64-*-openbsd*
3124 OpenBSD/alpha alpha*-*-openbsd*
3125 OpenBSD/sparc sparc-*-openbsd*
3126 OpenBSD/sparc64 sparc64-*-openbsd*
3128 * New debugging protocols
3130 M32R with SDI protocol m32r-*-elf*
3132 * "set prompt-escape-char" command deleted.
3134 The command "set prompt-escape-char" has been deleted. This command,
3135 and its very obscure effet on GDB's prompt, was never documented,
3136 tested, nor mentioned in the NEWS file.
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.
3145 Sun 3, running SunOS 3 m68*-*-sunos3*
3146 Sun 3, running SunOS 4 m68*-*-sunos4*
3147 Sun 2, running SunOS 3 m68000-*-sunos3*
3148 Sun 2, running SunOS 4 m68000-*-sunos4*
3149 Motorola 680x0 running LynxOS m68*-*-lynxos*
3150 AT&T 3b1/Unix pc m68*-att-*
3151 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3152 decstation mips-dec-* mips-little-*
3153 riscos mips-*-riscos* mips-*-sysv*
3154 sonymips mips-sony-*
3155 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3157 * REMOVED configurations and files
3159 SGI Irix-4.x mips-sgi-irix4 or iris4
3160 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3161 Z8000 simulator z8k-zilog-none or z8ksim
3162 Matsushita MN10200 w/simulator mn10200-*-*
3163 H8/500 simulator h8500-hitachi-hms or h8500hms
3164 HP/PA running BSD hppa*-*-bsd*
3165 HP/PA running OSF/1 hppa*-*-osf*
3166 HP/PA Pro target hppa*-*-pro*
3167 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3168 386BSD i[3456]86-*-bsd*
3169 Sequent family i[3456]86-sequent-sysv4*
3170 i[3456]86-sequent-sysv*
3171 i[3456]86-sequent-bsd*
3172 SPARC running LynxOS sparc-*-lynxos*
3173 SPARC running SunOS 4 sparc-*-sunos4*
3174 Tsqware Sparclet sparclet-*-*
3175 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3177 *** Changes in GDB 6.0:
3181 Support for debugging the Objective-C programming language has been
3182 integrated into GDB.
3184 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3186 DWARF 2's Call Frame Information makes available compiler generated
3187 information that more exactly describes the program's run-time stack.
3188 By using this information, GDB is able to provide more robust stack
3191 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3192 have been updated to use a new backtrace mechanism which includes
3193 DWARF 2 CFI support.
3197 GDB's remote protocol has been extended to include support for hosted
3198 file I/O (where the remote target uses GDB's file system). See GDB's
3199 remote protocol documentation for details.
3201 * All targets using the new architecture framework.
3203 All of GDB's targets have been updated to use the new internal
3204 architecture framework. The way is now open for future GDB releases
3205 to include cross-architecture native debugging support (i386 on amd64,
3208 * GNU/Linux's Thread Local Storage (TLS)
3210 GDB now includes support for for the GNU/Linux implementation of
3211 per-thread variables.
3213 * GNU/Linux's Native POSIX Thread Library (NPTL)
3215 GDB's thread code has been updated to work with either the new
3216 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3218 * Separate debug info.
3220 GDB, in conjunction with BINUTILS, now supports a mechanism for
3221 automatically loading debug information from a separate file. Instead
3222 of shipping full debug and non-debug versions of system libraries,
3223 system integrators can now instead ship just the stripped libraries
3224 and optional debug files.
3226 * DWARF 2 Location Expressions
3228 DWARF 2 Location Expressions allow the compiler to more completely
3229 describe the location of variables (even in optimized code) to the
3232 GDB now includes preliminary support for location expressions (support
3233 for DW_OP_piece is still missing).
3237 A number of long standing bugs that caused GDB to die while starting a
3238 Java application have been fixed. GDB's Java support is now
3239 considered "useable".
3241 * GNU/Linux support for fork, vfork, and exec.
3243 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3244 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3247 * GDB supports logging output to a file
3249 There are two new commands, "set logging" and "show logging", which can be
3250 used to capture GDB's output to a file.
3252 * The meaning of "detach" has changed for gdbserver
3254 The "detach" command will now resume the application, as documented. To
3255 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3258 * d10v, m68hc11 `regs' command deprecated
3260 The `info registers' command has been updated so that it displays the
3261 registers using a format identical to the old `regs' command.
3265 A new command, "maint set profile on/off", has been added. This command can
3266 be used to enable or disable profiling while running GDB, to profile a
3267 session or a set of commands. In addition there is a new configure switch,
3268 "--enable-profiling", which will cause GDB to be compiled with profiling
3269 data, for more informative profiling results.
3271 * Default MI syntax changed to "mi2".
3273 The default MI (machine interface) syntax, enabled by the command line
3274 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3275 "mi1", can be enabled by specifying the option "-i=mi1".
3277 Support for the original "mi0" syntax (included in GDB 5.0) has been
3280 Fix for gdb/192: removed extraneous space when displaying frame level.
3281 Fix for gdb/672: update changelist is now output in mi list format.
3282 Fix for gdb/702: a -var-assign that updates the value now shows up
3283 in a subsequent -var-update.
3285 * New native configurations.
3287 FreeBSD/amd64 x86_64-*-freebsd*
3289 * Multi-arched targets.
3291 HP/PA HPUX11 hppa*-*-hpux*
3292 Renesas M32R/D w/simulator m32r-*-elf*
3294 * OBSOLETE configurations and files
3296 Configurations that have been declared obsolete in this release have
3297 been commented out. Unless there is activity to revive these
3298 configurations, the next release of GDB will have their sources
3299 permanently REMOVED.
3301 Z8000 simulator z8k-zilog-none or z8ksim
3302 Matsushita MN10200 w/simulator mn10200-*-*
3303 H8/500 simulator h8500-hitachi-hms or h8500hms
3304 HP/PA running BSD hppa*-*-bsd*
3305 HP/PA running OSF/1 hppa*-*-osf*
3306 HP/PA Pro target hppa*-*-pro*
3307 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3308 Sequent family i[3456]86-sequent-sysv4*
3309 i[3456]86-sequent-sysv*
3310 i[3456]86-sequent-bsd*
3311 Tsqware Sparclet sparclet-*-*
3312 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3314 * REMOVED configurations and files
3317 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3318 IBM AIX PS/2 i[3456]86-*-aix
3319 i386 running Mach 3.0 i[3456]86-*-mach3*
3320 i386 running Mach i[3456]86-*-mach*
3321 i386 running OSF/1 i[3456]86-*osf1mk*
3322 HP/Apollo 68k Family m68*-apollo*-sysv*,
3324 m68*-hp-bsd*, m68*-hp-hpux*
3325 Argonaut Risc Chip (ARC) arc-*-*
3326 Mitsubishi D30V d30v-*-*
3327 Fujitsu FR30 fr30-*-elf*
3328 OS/9000 i[34]86-*-os9k
3329 I960 with MON960 i960-*-coff
3331 * MIPS $fp behavior changed
3333 The convenience variable $fp, for the MIPS, now consistently returns
3334 the address of the current frame's base. Previously, depending on the
3335 context, $fp could refer to either $sp or the current frame's base
3336 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3337 The GNU Source-Level Debugger''.
3339 *** Changes in GDB 5.3:
3341 * GNU/Linux shared library multi-threaded performance improved.
3343 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3344 `/proc', in preference to `ptrace' for memory reads. This may result
3345 in an improvement in the start-up time of multi-threaded, shared
3346 library applications when run under GDB. One GDB user writes: ``loads
3347 shared libs like mad''.
3349 * ``gdbserver'' now supports multi-threaded applications on some targets
3351 Support for debugging multi-threaded applications which use
3352 the GNU/Linux LinuxThreads package has been added for
3353 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3354 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3356 * GDB now supports C/C++ preprocessor macros.
3358 GDB now expands preprocessor macro invocations in C/C++ expressions,
3359 and provides various commands for showing macro definitions and how
3362 The new command `macro expand EXPRESSION' expands any macro
3363 invocations in expression, and shows the result.
3365 The new command `show macro MACRO-NAME' shows the definition of the
3366 macro named MACRO-NAME, and where it was defined.
3368 Most compilers don't include information about macros in the debugging
3369 information by default. In GCC 3.1, for example, you need to compile
3370 your program with the options `-gdwarf-2 -g3'. If the macro
3371 information is present in the executable, GDB will read it.
3373 * Multi-arched targets.
3375 DEC Alpha (partial) alpha*-*-*
3376 DEC VAX (partial) vax-*-*
3378 National Semiconductor NS32000 (partial) ns32k-*-*
3379 Motorola 68000 (partial) m68k-*-*
3380 Motorola MCORE mcore-*-*
3384 Fujitsu FRV architecture added by Red Hat frv*-*-*
3387 * New native configurations
3389 Alpha NetBSD alpha*-*-netbsd*
3390 SH NetBSD sh*-*-netbsdelf*
3391 MIPS NetBSD mips*-*-netbsd*
3392 UltraSPARC NetBSD sparc64-*-netbsd*
3394 * OBSOLETE configurations and files
3396 Configurations that have been declared obsolete in this release have
3397 been commented out. Unless there is activity to revive these
3398 configurations, the next release of GDB will have their sources
3399 permanently REMOVED.
3401 Mitsubishi D30V d30v-*-*
3402 OS/9000 i[34]86-*-os9k
3403 IBM AIX PS/2 i[3456]86-*-aix
3404 Fujitsu FR30 fr30-*-elf*
3405 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3406 Argonaut Risc Chip (ARC) arc-*-*
3407 i386 running Mach 3.0 i[3456]86-*-mach3*
3408 i386 running Mach i[3456]86-*-mach*
3409 i386 running OSF/1 i[3456]86-*osf1mk*
3410 HP/Apollo 68k Family m68*-apollo*-sysv*,
3412 m68*-hp-bsd*, m68*-hp-hpux*
3413 I960 with MON960 i960-*-coff
3415 * OBSOLETE languages
3417 CHILL, a Pascal like language used by telecommunications companies.
3419 * REMOVED configurations and files
3421 AMD 29k family via UDI a29k-amd-udi, udi29k
3422 A29K VxWorks a29k-*-vxworks
3423 AMD 29000 embedded, using EBMON a29k-none-none
3424 AMD 29000 embedded with COFF a29k-none-coff
3425 AMD 29000 embedded with a.out a29k-none-aout
3427 testsuite/gdb.hp/gdb.threads-hp/ directory
3429 * New command "set max-user-call-depth <nnn>"
3431 This command allows the user to limit the call depth of user-defined
3432 commands. The default is 1024.
3434 * Changes in FreeBSD/i386 native debugging.
3436 Support for the "generate-core-file" has been added.
3438 * New commands "dump", "append", and "restore".
3440 These commands allow data to be copied from target memory
3441 to a bfd-format or binary file (dump and append), and back
3442 from a file into memory (restore).
3444 * Improved "next/step" support on multi-processor Alpha Tru64.
3446 The previous single-step mechanism could cause unpredictable problems,
3447 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3448 of a software single-step mechanism prevents this.
3450 *** Changes in GDB 5.2.1:
3458 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3459 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3460 Fix, by Joel Brobecker imported from mainline.
3462 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3463 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3464 Fix, by Fred Fish, imported from mainline.
3466 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3467 Surprisingly enough, it works now.
3468 By Michal Ludvig, imported from mainline.
3470 i386 hardware watchpoint support:
3471 avoid misses on second run for some targets.
3472 By Pierre Muller, imported from mainline.
3474 *** Changes in GDB 5.2:
3476 * New command "set trust-readonly-sections on[off]".
3478 This command is a hint that tells gdb that read-only sections
3479 really are read-only (ie. that their contents will not change).
3480 In this mode, gdb will go to the object file rather than the
3481 target to read memory from read-only sections (such as ".text").
3482 This can be a significant performance improvement on some
3483 (notably embedded) targets.
3485 * New command "generate-core-file" (or "gcore").
3487 This new gdb command allows the user to drop a core file of the child
3488 process state at any time. So far it's been implemented only for
3489 GNU/Linux and Solaris, but should be relatively easily ported to other
3490 hosts. Argument is core file name (defaults to core.<pid>).
3492 * New command line option
3494 GDB now accepts --pid or -p followed by a process id.
3496 * Change in command line behavior -- corefiles vs. process ids.
3498 There is a subtle behavior in the way in which GDB handles
3499 command line arguments. The first non-flag argument is always
3500 a program to debug, but the second non-flag argument may either
3501 be a corefile or a process id. Previously, GDB would attempt to
3502 open the second argument as a corefile, and if that failed, would
3503 issue a superfluous error message and then attempt to attach it as
3504 a process. Now, if the second argument begins with a non-digit,
3505 it will be treated as a corefile. If it begins with a digit,
3506 GDB will attempt to attach it as a process, and if no such process
3507 is found, will then attempt to open it as a corefile.
3509 * Changes in ARM configurations.
3511 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3512 configuration is fully multi-arch.
3514 * New native configurations
3516 ARM NetBSD arm*-*-netbsd*
3517 x86 OpenBSD i[3456]86-*-openbsd*
3518 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3519 Sparc64 running FreeBSD sparc64-*-freebsd*
3523 Sanyo XStormy16 xstormy16-elf
3525 * OBSOLETE configurations and files
3527 Configurations that have been declared obsolete in this release have
3528 been commented out. Unless there is activity to revive these
3529 configurations, the next release of GDB will have their sources
3530 permanently REMOVED.
3532 AMD 29k family via UDI a29k-amd-udi, udi29k
3533 A29K VxWorks a29k-*-vxworks
3534 AMD 29000 embedded, using EBMON a29k-none-none
3535 AMD 29000 embedded with COFF a29k-none-coff
3536 AMD 29000 embedded with a.out a29k-none-aout
3538 testsuite/gdb.hp/gdb.threads-hp/ directory
3540 * REMOVED configurations and files
3542 TI TMS320C80 tic80-*-*
3544 PowerPC Solaris powerpcle-*-solaris*
3545 PowerPC Windows NT powerpcle-*-cygwin32
3546 PowerPC Netware powerpc-*-netware*
3547 Harris/CXUX m88k m88*-harris-cxux*
3548 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3549 ns32k-utek-sysv* ns32k-utek-*
3550 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3551 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3552 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3553 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3554 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3556 * Changes to command line processing
3558 The new `--args' feature can be used to specify command-line arguments
3559 for the inferior from gdb's command line.
3561 * Changes to key bindings
3563 There is a new `operate-and-get-next' function bound to `C-o'.
3565 *** Changes in GDB 5.1.1
3567 Fix compile problem on DJGPP.
3569 Fix a problem with floating-point registers on the i386 being
3572 Fix to stop GDB crashing on .debug_str debug info.
3574 Numerous documentation fixes.
3576 Numerous testsuite fixes.
3578 *** Changes in GDB 5.1:
3580 * New native configurations
3582 Alpha FreeBSD alpha*-*-freebsd*
3583 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3584 MIPS GNU/Linux mips*-*-linux*
3585 MIPS SGI Irix 6.x mips*-sgi-irix6*
3586 ia64 AIX ia64-*-aix*
3587 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3591 Motorola 68HC11 and 68HC12 m68hc11-elf
3593 UltraSparc running GNU/Linux sparc64-*-linux*
3595 * OBSOLETE configurations and files
3597 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3598 Harris/CXUX m88k m88*-harris-cxux*
3599 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3600 ns32k-utek-sysv* ns32k-utek-*
3601 TI TMS320C80 tic80-*-*
3603 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3604 PowerPC Solaris powerpcle-*-solaris*
3605 PowerPC Windows NT powerpcle-*-cygwin32
3606 PowerPC Netware powerpc-*-netware*
3607 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3608 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3609 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3610 Apple Macintosh (MPW) host N/A
3612 stuff.c (Program to stuff files into a specially prepared space in kdb)
3613 kdb-start.c (Main loop for the standalone kernel debugger)
3615 Configurations that have been declared obsolete in this release have
3616 been commented out. Unless there is activity to revive these
3617 configurations, the next release of GDB will have their sources
3618 permanently REMOVED.
3620 * REMOVED configurations and files
3622 Altos 3068 m68*-altos-*
3623 Convex c1-*-*, c2-*-*
3625 ARM RISCix arm-*-* (as host)
3629 * GDB has been converted to ISO C.
3631 GDB's source code has been converted to ISO C. In particular, the
3632 sources are fully protoized, and rely on standard headers being
3637 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3639 * The MI enabled by default.
3641 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3642 revised and enabled by default. Packages which use GDB as a debugging
3643 engine behind a UI or another front end are encouraged to switch to
3644 using the GDB/MI interface, instead of the old annotations interface
3645 which is now deprecated.
3647 * Support for debugging Pascal programs.
3649 GDB now includes support for debugging Pascal programs. The following
3650 main features are supported:
3652 - Pascal-specific data types such as sets;
3654 - automatic recognition of Pascal sources based on file-name
3657 - Pascal-style display of data types, variables, and functions;
3659 - a Pascal expression parser.
3661 However, some important features are not yet supported.
3663 - Pascal string operations are not supported at all;
3665 - there are some problems with boolean types;
3667 - Pascal type hexadecimal constants are not supported
3668 because they conflict with the internal variables format;
3670 - support for Pascal objects and classes is not full yet;
3672 - unlike Pascal, GDB is case-sensitive for symbol names.
3674 * Changes in completion.
3676 Commands such as `shell', `run' and `set args', which pass arguments
3677 to inferior programs, now complete on file names, similar to what
3678 users expect at the shell prompt.
3680 Commands which accept locations, such as `disassemble', `print',
3681 `breakpoint', `until', etc. now complete on filenames as well as
3682 program symbols. Thus, if you type "break foob TAB", and the source
3683 files linked into the programs include `foobar.c', that file name will
3684 be one of the candidates for completion. However, file names are not
3685 considered for completion after you typed a colon that delimits a file
3686 name from a name of a function in that file, as in "break foo.c:bar".
3688 `set demangle-style' completes on available demangling styles.
3690 * New platform-independent commands:
3692 It is now possible to define a post-hook for a command as well as a
3693 hook that runs before the command. For more details, see the
3694 documentation of `hookpost' in the GDB manual.
3696 * Changes in GNU/Linux native debugging.
3698 Support for debugging multi-threaded programs has been completely
3699 revised for all platforms except m68k and sparc. You can now debug as
3700 many threads as your system allows you to have.
3702 Attach/detach is supported for multi-threaded programs.
3704 Support for SSE registers was added for x86. This doesn't work for
3705 multi-threaded programs though.
3707 * Changes in MIPS configurations.
3709 Multi-arch support is enabled for all MIPS configurations.
3711 GDB can now be built as native debugger on SGI Irix 6.x systems for
3712 debugging n32 executables. (Debugging 64-bit executables is not yet
3715 * Unified support for hardware watchpoints in all x86 configurations.
3717 Most (if not all) native x86 configurations support hardware-assisted
3718 breakpoints and watchpoints in a unified manner. This support
3719 implements debug register sharing between watchpoints, which allows to
3720 put a virtually infinite number of watchpoints on the same address,
3721 and also supports watching regions up to 16 bytes with several debug
3724 The new maintenance command `maintenance show-debug-regs' toggles
3725 debugging print-outs in functions that insert, remove, and test
3726 watchpoints and hardware breakpoints.
3728 * Changes in the DJGPP native configuration.
3730 New command ``info dos sysinfo'' displays assorted information about
3731 the CPU, OS, memory, and DPMI server.
3733 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3734 display information about segment descriptors stored in GDT, LDT, and
3737 New commands ``info dos pde'' and ``info dos pte'' display entries
3738 from Page Directory and Page Tables (for now works with CWSDPMI only).
3739 New command ``info dos address-pte'' displays the Page Table entry for
3740 a given linear address.
3742 GDB can now pass command lines longer than 126 characters to the
3743 program being debugged (requires an update to the libdbg.a library
3744 which is part of the DJGPP development kit).
3746 DWARF2 debug info is now supported.
3748 It is now possible to `step' and `next' through calls to `longjmp'.
3750 * Changes in documentation.
3752 All GDB documentation was converted to GFDL, the GNU Free
3753 Documentation License.
3755 Tracepoints-related commands are now fully documented in the GDB
3758 TUI, the Text-mode User Interface, is now documented in the manual.
3760 Tracepoints-related commands are now fully documented in the GDB
3763 The "GDB Internals" manual now has an index. It also includes
3764 documentation of `ui_out' functions, GDB coding standards, x86
3765 hardware watchpoints, and memory region attributes.
3767 * GDB's version number moved to ``version.in''
3769 The Makefile variable VERSION has been replaced by the file
3770 ``version.in''. People creating GDB distributions should update the
3771 contents of this file.
3775 GUD support is now a standard part of the EMACS distribution.
3777 *** Changes in GDB 5.0:
3779 * Improved support for debugging FP programs on x86 targets
3781 Unified and much-improved support for debugging floating-point
3782 programs on all x86 targets. In particular, ``info float'' now
3783 displays the FP registers in the same format on all x86 targets, with
3784 greater level of detail.
3786 * Improvements and bugfixes in hardware-assisted watchpoints
3788 It is now possible to watch array elements, struct members, and
3789 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3790 on x86 targets no longer erroneously trigger when the address is
3793 * Improvements in the native DJGPP version of GDB
3795 The distribution now includes all the scripts and auxiliary files
3796 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3797 machines ``out of the box''.
3799 The DJGPP version can now debug programs that use signals. It is
3800 possible to catch signals that happened in the debuggee, deliver
3801 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3802 would kill the program being debugged.) Programs that hook hardware
3803 interrupts (keyboard, timer, etc.) can also be debugged.
3805 It is now possible to debug DJGPP programs that redirect their
3806 standard handles or switch them to raw (as opposed to cooked) mode, or
3807 even close them. The command ``run < foo > bar'' works as expected,
3808 and ``info terminal'' reports useful information about the debuggee's
3809 terminal, including raw/cooked mode, redirection, etc.
3811 The DJGPP version now uses termios functions for console I/O, which
3812 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3815 DOS-style file names with drive letters are now fully supported by
3818 It is now possible to debug DJGPP programs that switch their working
3819 directory. It is also possible to rerun the debuggee any number of
3820 times without restarting GDB; thus, you can use the same setup,
3821 breakpoints, etc. for many debugging sessions.
3823 * New native configurations
3825 ARM GNU/Linux arm*-*-linux*
3826 PowerPC GNU/Linux powerpc-*-linux*
3830 Motorola MCore mcore-*-*
3831 x86 VxWorks i[3456]86-*-vxworks*
3832 PowerPC VxWorks powerpc-*-vxworks*
3833 TI TMS320C80 tic80-*-*
3835 * OBSOLETE configurations
3837 Altos 3068 m68*-altos-*
3838 Convex c1-*-*, c2-*-*
3840 ARM RISCix arm-*-* (as host)
3843 Configurations that have been declared obsolete will be commented out,
3844 but the code will be left in place. If there is no activity to revive
3845 these configurations before the next release of GDB, the sources will
3846 be permanently REMOVED.
3848 * Gould support removed
3850 Support for the Gould PowerNode and NP1 has been removed.
3852 * New features for SVR4
3854 On SVR4 native platforms (such as Solaris), if you attach to a process
3855 without first loading a symbol file, GDB will now attempt to locate and
3856 load symbols from the running process's executable file.
3858 * Many C++ enhancements
3860 C++ support has been greatly improved. Overload resolution now works properly
3861 in almost all cases. RTTI support is on the way.
3863 * Remote targets can connect to a sub-program
3865 A popen(3) style serial-device has been added. This device starts a
3866 sub-process (such as a stand-alone simulator) and then communicates
3867 with that. The sub-program to run is specified using the syntax
3868 ``|<program> <args>'' vis:
3870 (gdb) set remotedebug 1
3871 (gdb) target extended-remote |mn10300-elf-sim program-args
3873 * MIPS 64 remote protocol
3875 A long standing bug in the mips64 remote protocol where by GDB
3876 expected certain 32 bit registers (ex SR) to be transfered as 32
3877 instead of 64 bits has been fixed.
3879 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3880 added to provide backward compatibility with older versions of GDB.
3882 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3884 The command ``set remotebinarydownload'' command has been replaced by
3885 ``set remote X-packet''. Other commands in ``set remote'' family
3886 include ``set remote P-packet''.
3888 * Breakpoint commands accept ranges.
3890 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3891 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3892 ``tracepoint passcount'' also accepts a range of tracepoints.
3894 * ``apropos'' command added.
3896 The ``apropos'' command searches through command names and
3897 documentation strings, printing out matches, making it much easier to
3898 try to find a command that does what you are looking for.
3902 A new machine oriented interface (MI) has been added to GDB. This
3903 interface is designed for debug environments running GDB as a separate
3904 process. This is part of the long term libGDB project. See the
3905 "GDB/MI" chapter of the GDB manual for further information. It can be
3906 enabled by configuring with:
3908 .../configure --enable-gdbmi
3910 *** Changes in GDB-4.18:
3912 * New native configurations
3914 HP-UX 10.20 hppa*-*-hpux10.20
3915 HP-UX 11.x hppa*-*-hpux11.0*
3916 M68K GNU/Linux m68*-*-linux*
3920 Fujitsu FR30 fr30-*-elf*
3921 Intel StrongARM strongarm-*-*
3922 Mitsubishi D30V d30v-*-*
3924 * OBSOLETE configurations
3926 Gould PowerNode, NP1 np1-*-*, pn-*-*
3928 Configurations that have been declared obsolete will be commented out,
3929 but the code will be left in place. If there is no activity to revive
3930 these configurations before the next release of GDB, the sources will
3931 be permanently REMOVED.
3935 As a compatibility experiment, GDB's source files buildsym.h and
3936 buildsym.c have been converted to pure standard C, no longer
3937 containing any K&R compatibility code. We believe that all systems in
3938 use today either come with a standard C compiler, or have a GCC port
3939 available. If this is not true, please report the affected
3940 configuration to bug-gdb@gnu.org immediately. See the README file for
3941 information about getting a standard C compiler if you don't have one
3946 GDB now uses readline 2.2.
3948 * set extension-language
3950 You can now control the mapping between filename extensions and source
3951 languages by using the `set extension-language' command. For instance,
3952 you can ask GDB to treat .c files as C++ by saying
3953 set extension-language .c c++
3954 The command `info extensions' lists all of the recognized extensions
3955 and their associated languages.
3957 * Setting processor type for PowerPC and RS/6000
3959 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3960 you can use the `set processor' command to specify what variant of the
3961 PowerPC family you are debugging. The command
3965 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3966 following PowerPC and RS6000 variants:
3968 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3969 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3971 403GC IBM PowerPC 403GC
3972 505 Motorola PowerPC 505
3973 860 Motorola PowerPC 860 or 850
3974 601 Motorola PowerPC 601
3975 602 Motorola PowerPC 602
3976 603 Motorola/IBM PowerPC 603 or 603e
3977 604 Motorola PowerPC 604 or 604e
3978 750 Motorola/IBM PowerPC 750 or 750
3980 At the moment, this command just tells GDB what to name the
3981 special-purpose processor registers. Since almost all the affected
3982 registers are inaccessible to user-level programs, this command is
3983 only useful for remote debugging in its present form.
3987 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3988 more extensive support for HP-UX. Added features include shared
3989 library support, kernel threads and hardware watchpoints for 11.00,
3990 support for HP's ANSI C and C++ compilers, and a compatibility mode
3991 for xdb and dbx commands.
3995 HP's donation includes the new concept of catchpoints, which is a
3996 generalization of the old catch command. On HP-UX, it is now possible
3997 to catch exec, fork, and vfork, as well as library loading.
3999 This means that the existing catch command has changed; its first
4000 argument now specifies the type of catch to be set up. See the
4001 output of "help catch" for a list of catchpoint types.
4003 * Debugging across forks
4005 On HP-UX, you can choose which process to debug when a fork() happens
4010 HP has donated a curses-based terminal user interface (TUI). To get
4011 it, build with --enable-tui. Although this can be enabled for any
4012 configuration, at present it only works for native HP debugging.
4014 * GDB remote protocol additions
4016 A new protocol packet 'X' that writes binary data is now available.
4017 Default behavior is to try 'X', then drop back to 'M' if the stub
4018 fails to respond. The settable variable `remotebinarydownload'
4019 allows explicit control over the use of 'X'.
4021 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
4022 full 64-bit address. The command
4024 set remoteaddresssize 32
4026 can be used to revert to the old behaviour. For existing remote stubs
4027 the change should not be noticed, as the additional address information
4030 In order to assist in debugging stubs, you may use the maintenance
4031 command `packet' to send any text string to the stub. For instance,
4033 maint packet heythere
4035 sends the packet "$heythere#<checksum>". Note that it is very easy to
4036 disrupt a debugging session by sending the wrong packet at the wrong
4039 The compare-sections command allows you to compare section data on the
4040 target to what is in the executable file without uploading or
4041 downloading, by comparing CRC checksums.
4043 * Tracing can collect general expressions
4045 You may now collect general expressions at tracepoints. This requires
4046 further additions to the target-side stub; see tracepoint.c and
4047 doc/agentexpr.texi for further details.
4049 * mask-address variable for Mips
4051 For Mips targets, you may control the zeroing of the upper 32 bits of
4052 a 64-bit address by entering `set mask-address on'. This is mainly
4053 of interest to users of embedded R4xxx and R5xxx processors.
4055 * Higher serial baud rates
4057 GDB's serial code now allows you to specify baud rates 57600, 115200,
4058 230400, and 460800 baud. (Note that your host system may not be able
4059 to achieve all of these rates.)
4063 The i960 configuration now includes an initial implementation of a
4064 builtin simulator, contributed by Jim Wilson.
4067 *** Changes in GDB-4.17:
4069 * New native configurations
4071 Alpha GNU/Linux alpha*-*-linux*
4072 Unixware 2.x i[3456]86-unixware2*
4073 Irix 6.x mips*-sgi-irix6*
4074 PowerPC GNU/Linux powerpc-*-linux*
4075 PowerPC Solaris powerpcle-*-solaris*
4076 Sparc GNU/Linux sparc-*-linux*
4077 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4081 Argonaut Risc Chip (ARC) arc-*-*
4082 Hitachi H8/300S h8300*-*-*
4083 Matsushita MN10200 w/simulator mn10200-*-*
4084 Matsushita MN10300 w/simulator mn10300-*-*
4085 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4086 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4087 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4088 Mitsubishi D10V w/simulator d10v-*-*
4089 Mitsubishi M32R/D w/simulator m32r-*-elf*
4090 Tsqware Sparclet sparclet-*-*
4091 NEC V850 w/simulator v850-*-*
4093 * New debugging protocols
4095 ARM with RDI protocol arm*-*-*
4096 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4097 DDB and LSI variants of PMON protocol mips*-*-*
4098 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4099 PowerPC with SDS protocol powerpc{,le}-*-eabi
4100 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4104 All configurations can now understand and use the DWARF 2 debugging
4105 format. The choice is automatic, if the symbol file contains DWARF 2
4110 GDB now includes basic Java language support. This support is
4111 only useful with Java compilers that produce native machine code.
4113 * solib-absolute-prefix and solib-search-path
4115 For SunOS and SVR4 shared libraries, you may now set the prefix for
4116 loading absolute shared library symbol files, and the search path for
4117 locating non-absolute shared library symbol files.
4119 * Live range splitting
4121 GDB can now effectively debug code for which GCC has performed live
4122 range splitting as part of its optimization. See gdb/doc/LRS for
4123 more details on the expected format of the stabs information.
4127 GDB's support for the GNU Hurd, including thread debugging, has been
4128 updated to work with current versions of the Hurd.
4132 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4133 instruction set. ARM GDB automatically detects when Thumb
4134 instructions are in use, and adjusts disassembly and backtracing
4139 GDB's MIPS target configurations now handle the MIP16 16-bit
4144 GDB now includes support for overlays; if an executable has been
4145 linked such that multiple sections are based at the same address, GDB
4146 will decide which section to use for symbolic info. You can choose to
4147 control the decision manually, using overlay commands, or implement
4148 additional target-side support and use "overlay load-target" to bring
4149 in the overlay mapping. Do "help overlay" for more detail.
4153 The command "info symbol <address>" displays information about
4154 the symbol at the specified address.
4158 The standard remote protocol now includes an extension that allows
4159 asynchronous collection and display of trace data. This requires
4160 extensive support in the target-side debugging stub. Tracing mode
4161 includes a new interaction mode in GDB and new commands: see the
4162 file tracepoint.c for more details.
4166 Configurations for embedded MIPS now include a simulator contributed
4167 by Cygnus Solutions. The simulator supports the instruction sets
4168 of most MIPS variants.
4172 Sparc configurations may now include the ERC32 simulator contributed
4173 by the European Space Agency. The simulator is not built into
4174 Sparc targets by default; configure with --enable-sim to include it.
4178 For target configurations that may include multiple variants of a
4179 basic architecture (such as MIPS and SH), you may now set the
4180 architecture explicitly. "set arch" sets, "info arch" lists
4181 the possible architectures.
4183 *** Changes in GDB-4.16:
4185 * New native configurations
4187 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4188 M68K NetBSD m68k-*-netbsd*
4189 PowerPC AIX 4.x powerpc-*-aix*
4190 PowerPC MacOS powerpc-*-macos*
4191 PowerPC Windows NT powerpcle-*-cygwin32
4192 RS/6000 AIX 4.x rs6000-*-aix4*
4196 ARM with RDP protocol arm-*-*
4197 I960 with MON960 i960-*-coff
4198 MIPS VxWorks mips*-*-vxworks*
4199 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4200 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4202 Matra Sparclet sparclet-*-*
4206 The powerpc-eabi configuration now includes the PSIM simulator,
4207 contributed by Andrew Cagney, with assistance from Mike Meissner.
4208 PSIM is a very elaborate model of the PowerPC, including not only
4209 basic instruction set execution, but also details of execution unit
4210 performance and I/O hardware. See sim/ppc/README for more details.
4214 GDB now works with Solaris 2.5.
4216 * Windows 95/NT native
4218 GDB will now work as a native debugger on Windows 95 and Windows NT.
4219 To build it from source, you must use the "gnu-win32" environment,
4220 which uses a DLL to emulate enough of Unix to run the GNU tools.
4221 Further information, binaries, and sources are available at
4222 ftp.cygnus.com, under pub/gnu-win32.
4224 * dont-repeat command
4226 If a user-defined command includes the command `dont-repeat', then the
4227 command will not be repeated if the user just types return. This is
4228 useful if the command is time-consuming to run, so that accidental
4229 extra keystrokes don't run the same command many times.
4231 * Send break instead of ^C
4233 The standard remote protocol now includes an option to send a break
4234 rather than a ^C to the target in order to interrupt it. By default,
4235 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4237 * Remote protocol timeout
4239 The standard remote protocol includes a new variable `remotetimeout'
4240 that allows you to set the number of seconds before GDB gives up trying
4241 to read from the target. The default value is 2.
4243 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4245 By default GDB will automatically keep track of objects as they are
4246 loaded and unloaded by the dynamic linker. By using the command `set
4247 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4248 when shared library events occur, thus allowing you to set breakpoints
4249 in shared libraries which are explicitly loaded by the inferior.
4251 Note this feature does not work on hpux8. On hpux9 you must link
4252 /usr/lib/end.o into your program. This feature should work
4253 automatically on hpux10.
4255 * Irix 5.x hardware watchpoint support
4257 Irix 5 configurations now support the use of hardware watchpoints.
4259 * Mips protocol "SYN garbage limit"
4261 When debugging a Mips target using the `target mips' protocol, you
4262 may set the number of characters that GDB will ignore by setting
4263 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4264 every character. The default value is 1050.
4266 * Recording and replaying remote debug sessions
4268 If you set `remotelogfile' to the name of a file, gdb will write to it
4269 a recording of a remote debug session. This recording may then be
4270 replayed back to gdb using "gdbreplay". See gdbserver/README for
4271 details. This is useful when you have a problem with GDB while doing
4272 remote debugging; you can make a recording of the session and send it
4273 to someone else, who can then recreate the problem.
4275 * Speedups for remote debugging
4277 GDB includes speedups for downloading and stepping MIPS systems using
4278 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4279 and more efficient S-record downloading.
4281 * Memory use reductions and statistics collection
4283 GDB now uses less memory and reports statistics about memory usage.
4284 Try the `maint print statistics' command, for example.
4286 *** Changes in GDB-4.15:
4288 * Psymtabs for XCOFF
4290 The symbol reader for AIX GDB now uses partial symbol tables. This
4291 can greatly improve startup time, especially for large executables.
4293 * Remote targets use caching
4295 Remote targets now use a data cache to speed up communication with the
4296 remote side. The data cache could lead to incorrect results because
4297 it doesn't know about volatile variables, thus making it impossible to
4298 debug targets which use memory mapped I/O devices. `set remotecache
4299 off' turns the the data cache off.
4301 * Remote targets may have threads
4303 The standard remote protocol now includes support for multiple threads
4304 in the target system, using new protocol commands 'H' and 'T'. See
4305 gdb/remote.c for details.
4309 If GDB is configured with `--enable-netrom', then it will include
4310 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4311 acts as though it is a bank of ROM on the target board, but you can
4312 write into it over the network. GDB's support consists only of
4313 support for fast loading into the emulated ROM; to debug, you must use
4314 another protocol, such as standard remote protocol. The usual
4315 sequence is something like
4317 target nrom <netrom-hostname>
4319 target remote <netrom-hostname>:1235
4323 GDB now includes support for the Apple Macintosh, as a host only. It
4324 may be run as either an MPW tool or as a standalone application, and
4325 it can debug through the serial port. All the usual GDB commands are
4326 available, but to the target command, you must supply "serial" as the
4327 device type instead of "/dev/ttyXX". See mpw-README in the main
4328 directory for more information on how to build. The MPW configuration
4329 scripts */mpw-config.in support only a few targets, and only the
4330 mips-idt-ecoff target has been tested.
4334 GDB configuration now uses autoconf. This is not user-visible,
4335 but does simplify configuration and building.
4339 GDB now supports hpux10.
4341 *** Changes in GDB-4.14:
4343 * New native configurations
4345 x86 FreeBSD i[345]86-*-freebsd
4346 x86 NetBSD i[345]86-*-netbsd
4347 NS32k NetBSD ns32k-*-netbsd
4348 Sparc NetBSD sparc-*-netbsd
4352 A29K VxWorks a29k-*-vxworks
4353 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4354 CPU32 EST-300 emulator m68*-*-est*
4355 PowerPC ELF powerpc-*-elf
4358 * Alpha OSF/1 support for procfs
4360 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4361 possible to attach to running processes. As the mounting of the /proc
4362 filesystem is optional on the Alpha, GDB automatically determines
4363 the availability of /proc during startup. This can lead to problems
4364 if /proc is unmounted after GDB has been started.
4366 * Arguments to user-defined commands
4368 User commands may accept up to 10 arguments separated by whitespace.
4369 Arguments are accessed within the user command via $arg0..$arg9. A
4372 print $arg0 + $arg1 + $arg2
4374 To execute the command use:
4377 Defines the command "adder" which prints the sum of its three arguments.
4378 Note the arguments are text substitutions, so they may reference variables,
4379 use complex expressions, or even perform inferior function calls.
4381 * New `if' and `while' commands
4383 This makes it possible to write more sophisticated user-defined
4384 commands. Both commands take a single argument, which is the
4385 expression to evaluate, and must be followed by the commands to
4386 execute, one per line, if the expression is nonzero, the list being
4387 terminated by the word `end'. The `if' command list may include an
4388 `else' word, which causes the following commands to be executed only
4389 if the expression is zero.
4391 * Fortran source language mode
4393 GDB now includes partial support for Fortran 77. It will recognize
4394 Fortran programs and can evaluate a subset of Fortran expressions, but
4395 variables and functions may not be handled correctly. GDB will work
4396 with G77, but does not yet know much about symbols emitted by other
4399 * Better HPUX support
4401 Most debugging facilities now work on dynamic executables for HPPAs
4402 running hpux9 or later. You can attach to running dynamically linked
4403 processes, but by default the dynamic libraries will be read-only, so
4404 for instance you won't be able to put breakpoints in them. To change
4405 that behavior do the following before running the program:
4411 This will cause the libraries to be mapped private and read-write.
4412 To revert to the normal behavior, do this:
4418 You cannot set breakpoints or examine data in the library until after
4419 the library is loaded if the function/data symbols do not have
4422 GDB can now also read debug symbols produced by the HP C compiler on
4423 HPPAs (sorry, no C++, Fortran or 68k support).
4425 * Target byte order now dynamically selectable
4427 You can choose which byte order to use with a target system, via the
4428 commands "set endian big" and "set endian little", and you can see the
4429 current setting by using "show endian". You can also give the command
4430 "set endian auto", in which case GDB will use the byte order
4431 associated with the executable. Currently, only embedded MIPS
4432 configurations support dynamic selection of target byte order.
4434 * New DOS host serial code
4436 This version uses DPMI interrupts to handle buffered I/O, so you
4437 no longer need to run asynctsr when debugging boards connected to
4440 *** Changes in GDB-4.13:
4442 * New "complete" command
4444 This lists all the possible completions for the rest of the line, if it
4445 were to be given as a command itself. This is intended for use by emacs.
4447 * Trailing space optional in prompt
4449 "set prompt" no longer adds a space for you after the prompt you set. This
4450 allows you to set a prompt which ends in a space or one that does not.
4452 * Breakpoint hit counts
4454 "info break" now displays a count of the number of times the breakpoint
4455 has been hit. This is especially useful in conjunction with "ignore"; you
4456 can ignore a large number of breakpoint hits, look at the breakpoint info
4457 to see how many times the breakpoint was hit, then run again, ignoring one
4458 less than that number, and this will get you quickly to the last hit of
4461 * Ability to stop printing at NULL character
4463 "set print null-stop" will cause GDB to stop printing the characters of
4464 an array when the first NULL is encountered. This is useful when large
4465 arrays actually contain only short strings.
4467 * Shared library breakpoints
4469 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4470 breakpoints in shared libraries before the executable is run.
4472 * Hardware watchpoints
4474 There is a new hardware breakpoint for the watch command for sparclite
4475 targets. See gdb/sparclite/hw_breakpoint.note.
4477 Hardware watchpoints are also now supported under GNU/Linux.
4481 Annotations have been added. These are for use with graphical interfaces,
4482 and are still experimental. Currently only gdba.el uses these.
4484 * Improved Irix 5 support
4486 GDB now works properly with Irix 5.2.
4488 * Improved HPPA support
4490 GDB now works properly with the latest GCC and GAS.
4492 * New native configurations
4494 Sequent PTX4 i[34]86-sequent-ptx4
4495 HPPA running OSF/1 hppa*-*-osf*
4496 Atari TT running SVR4 m68*-*-sysv4*
4497 RS/6000 LynxOS rs6000-*-lynxos*
4501 OS/9000 i[34]86-*-os9k
4502 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4505 * Hitachi SH7000 and E7000-PC ICE support
4507 There is now support for communicating with the Hitachi E7000-PC ICE.
4508 This is available automatically when GDB is configured for the SH.
4512 As usual, a variety of small fixes and improvements, both generic
4513 and configuration-specific. See the ChangeLog for more detail.
4515 *** Changes in GDB-4.12:
4517 * Irix 5 is now supported
4521 GDB-4.12 on the HPPA has a number of changes which make it unable
4522 to debug the output from the currently released versions of GCC and
4523 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4524 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4525 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4528 *** Changes in GDB-4.11:
4530 * User visible changes:
4534 The "set remotedebug" option is now consistent between the mips remote
4535 target, remote targets using the gdb-specific protocol, UDI (AMD's
4536 debug protocol for the 29k) and the 88k bug monitor. It is now an
4537 integer specifying a debug level (normally 0 or 1, but 2 means more
4538 debugging info for the mips target).
4540 * DEC Alpha native support
4542 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4543 debug info, but GDB works fairly well with the DEC compiler and should
4544 work with a future GCC release. See the README file for a few
4545 Alpha-specific notes.
4547 * Preliminary thread implementation
4549 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4551 * LynxOS native and target support for 386
4553 This release has been hosted on LynxOS 2.2, and also can be configured
4554 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4557 * Improvements in C++ mangling/demangling.
4559 This release has much better g++ debugging, specifically in name
4560 mangling/demangling, virtual function calls, print virtual table,
4561 call methods, ...etc.
4563 *** Changes in GDB-4.10:
4565 * User visible changes:
4567 Remote debugging using the GDB-specific (`target remote') protocol now
4568 supports the `load' command. This is only useful if you have some
4569 other way of getting the stub to the target system, and you can put it
4570 somewhere in memory where it won't get clobbered by the download.
4572 Filename completion now works.
4574 When run under emacs mode, the "info line" command now causes the
4575 arrow to point to the line specified. Also, "info line" prints
4576 addresses in symbolic form (as well as hex).
4578 All vxworks based targets now support a user settable option, called
4579 vxworks-timeout. This option represents the number of seconds gdb
4580 should wait for responses to rpc's. You might want to use this if
4581 your vxworks target is, perhaps, a slow software simulator or happens
4582 to be on the far side of a thin network line.
4586 This release contains support for using a DEC alpha as a GDB host for
4587 cross debugging. Native alpha debugging is not supported yet.
4590 *** Changes in GDB-4.9:
4594 This is the first GDB release which is accompanied by a matching testsuite.
4595 The testsuite requires installation of dejagnu, which should be available
4596 via ftp from most sites that carry GNU software.
4600 'Cfront' style demangling has had its name changed to 'ARM' style, to
4601 emphasize that it was written from the specifications in the C++ Annotated
4602 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4603 disclaimers, it still generated too much confusion with users attempting to
4604 use gdb with AT&T cfront.
4608 GDB now uses a standard remote interface to a simulator library.
4609 So far, the library contains simulators for the Zilog Z8001/2, the
4610 Hitachi H8/300, H8/500 and Super-H.
4612 * New targets supported
4614 H8/300 simulator h8300-hitachi-hms or h8300hms
4615 H8/500 simulator h8500-hitachi-hms or h8500hms
4616 SH simulator sh-hitachi-hms or sh
4617 Z8000 simulator z8k-zilog-none or z8ksim
4618 IDT MIPS board over serial line mips-idt-ecoff
4620 Cross-debugging to GO32 targets is supported. It requires a custom
4621 version of the i386-stub.c module which is integrated with the
4622 GO32 memory extender.
4624 * New remote protocols
4626 MIPS remote debugging protocol.
4628 * New source languages supported
4630 This version includes preliminary support for Chill, a Pascal like language
4631 used by telecommunications companies. Chill support is also being integrated
4632 into the GNU compiler, but we don't know when it will be publically available.
4635 *** Changes in GDB-4.8:
4637 * HP Precision Architecture supported
4639 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4640 version of this support was available as a set of patches from the
4641 University of Utah. GDB does not support debugging of programs
4642 compiled with the HP compiler, because HP will not document their file
4643 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4644 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4646 Many problems in the preliminary version have been fixed.
4648 * Faster and better demangling
4650 We have improved template demangling and fixed numerous bugs in the GNU style
4651 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4652 character types (wchar_t) are now supported. Demangling of each symbol is now
4653 only done once, and is cached when the symbol table for a file is read in.
4654 This results in a small increase in memory usage for C programs, a moderate
4655 increase in memory usage for C++ programs, and a fantastic speedup in
4658 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4659 from the specifications in the Annotated Reference Manual, which AT&T's
4660 compiler does not actually implement.
4662 * G++ multiple inheritance compiler problem
4664 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4665 inheritance lattices was reworked to properly discover ambiguities. We
4666 recently found an example which causes this new algorithm to fail in a
4667 very subtle way, producing bad debug information for those classes.
4668 The file 'gcc.patch' (in this directory) can be applied to gcc to
4669 circumvent the problem. A future GCC release will contain a complete
4672 The previous G++ debug info problem (mentioned below for the gdb-4.7
4673 release) is fixed in gcc version 2.3.2.
4675 * Improved configure script
4677 The `configure' script will now attempt to guess your system type if
4678 you don't supply a host system type. The old scheme of supplying a
4679 host system triplet is preferable over using this. All the magic is
4680 done in the new `config.guess' script. Examine it for details.
4682 We have also brought our configure script much more in line with the FSF's
4683 version. It now supports the --with-xxx options. In particular,
4684 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4685 The resulting GDB will not be able to read arbitrary object file formats --
4686 only the format ``expected'' to be used on the configured target system.
4687 We hope to make this the default in a future release.
4689 * Documentation improvements
4691 There's new internal documentation on how to modify GDB, and how to
4692 produce clean changes to the code. We implore people to read it
4693 before submitting changes.
4695 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4696 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4697 `info' files are also provided. To build `info' files from scratch,
4698 you will need the latest `makeinfo' release, which will be available in
4699 a future texinfo-X.Y release.
4701 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4702 We're not sure exactly which versions have this problem, but it has
4703 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4704 or better. If that isn't possible, there is a patch in
4705 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4706 around this problem.
4710 GDB now supports array constants that can be used in expressions typed in by
4711 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4712 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4715 The new directory `gdb/sparclite' contains a program that demonstrates
4716 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4718 * New native hosts supported
4720 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4721 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4723 * New targets supported
4725 AMD 29k family via UDI a29k-amd-udi or udi29k
4727 * New file formats supported
4729 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4730 HPUX core files, and SCO 3.2v2 core files.
4734 Attaching to processes now works again; thanks for the many bug reports.
4736 We have also stomped on a bunch of core dumps caused by
4737 printf_filtered("%s") problems.
4739 We eliminated a copyright problem on the rpc and ptrace header files
4740 for VxWorks, which was discovered at the last minute during the 4.7
4741 release. You should now be able to build a VxWorks GDB.
4743 You can now interrupt gdb while an attached process is running. This
4744 will cause the attached process to stop, and give control back to GDB.
4746 We fixed problems caused by using too many file descriptors
4747 for reading symbols from object files and libraries. This was
4748 especially a problem for programs that used many (~100) shared
4751 The `step' command now only enters a subroutine if there is line number
4752 information for the subroutine. Otherwise it acts like the `next'
4753 command. Previously, `step' would enter subroutines if there was
4754 any debugging information about the routine. This avoids problems
4755 when using `cc -g1' on MIPS machines.
4757 * Internal improvements
4759 GDB's internal interfaces have been improved to make it easier to support
4760 debugging of multiple languages in the future.
4762 GDB now uses a common structure for symbol information internally.
4763 Minimal symbols (derived from linkage symbols in object files), partial
4764 symbols (from a quick scan of debug information), and full symbols
4765 contain a common subset of information, making it easier to write
4766 shared code that handles any of them.
4768 * New command line options
4770 We now accept --silent as an alias for --quiet.
4774 The memory-mapped-malloc library is now licensed under the GNU Library
4775 General Public License.
4777 *** Changes in GDB-4.7:
4779 * Host/native/target split
4781 GDB has had some major internal surgery to untangle the support for
4782 hosts and remote targets. Now, when you configure GDB for a remote
4783 target, it will no longer load in all of the support for debugging
4784 local programs on the host. When fully completed and tested, this will
4785 ensure that arbitrary host/target combinations are possible.
4787 The primary conceptual shift is to separate the non-portable code in
4788 GDB into three categories. Host specific code is required any time GDB
4789 is compiled on that host, regardless of the target. Target specific
4790 code relates to the peculiarities of the target, but can be compiled on
4791 any host. Native specific code is everything else: it can only be
4792 built when the host and target are the same system. Child process
4793 handling and core file support are two common `native' examples.
4795 GDB's use of /proc for controlling Unix child processes is now cleaner.
4796 It has been split out into a single module under the `target_ops' vector,
4797 plus two native-dependent functions for each system that uses /proc.
4799 * New hosts supported
4801 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4802 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4803 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4805 * New targets supported
4807 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4808 68030 and CPU32 m68030-*-*, m68332-*-*
4810 * New native hosts supported
4812 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4813 (386bsd is not well tested yet)
4814 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4816 * New file formats supported
4818 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4819 supports reading of `a.out.adobe' object files, which are an a.out
4820 format extended with minimal information about multiple sections.
4824 `show copying' is the same as the old `info copying'.
4825 `show warranty' is the same as `info warrantee'.
4826 These were renamed for consistency. The old commands continue to work.
4828 `info handle' is a new alias for `info signals'.
4830 You can now define pre-command hooks, which attach arbitrary command
4831 scripts to any command. The commands in the hook will be executed
4832 prior to the user's command. You can also create a hook which will be
4833 executed whenever the program stops. See gdb.texinfo.
4837 We now deal with Cfront style name mangling, and can even extract type
4838 info from mangled symbols. GDB can automatically figure out which
4839 symbol mangling style your C++ compiler uses.
4841 Calling of methods and virtual functions has been improved as well.
4845 The crash that occured when debugging Sun Ansi-C compiled binaries is
4846 fixed. This was due to mishandling of the extra N_SO stabs output
4849 We also finally got Ultrix 4.2 running in house, and fixed core file
4850 support, with help from a dozen people on the net.
4852 John M. Farrell discovered that the reason that single-stepping was so
4853 slow on all of the Mips based platforms (primarily SGI and DEC) was
4854 that we were trying to demangle and lookup a symbol used for internal
4855 purposes on every instruction that was being stepped through. Changing
4856 the name of that symbol so that it couldn't be mistaken for a C++
4857 mangled symbol sped things up a great deal.
4859 Rich Pixley sped up symbol lookups in general by getting much smarter
4860 about when C++ symbol mangling is necessary. This should make symbol
4861 completion (TAB on the command line) much faster. It's not as fast as
4862 we'd like, but it's significantly faster than gdb-4.6.
4866 A new user controllable variable 'call_scratch_address' can
4867 specify the location of a scratch area to be used when GDB
4868 calls a function in the target. This is necessary because the
4869 usual method of putting the scratch area on the stack does not work
4870 in systems that have separate instruction and data spaces.
4872 We integrated changes to support the 29k UDI (Universal Debugger
4873 Interface), but discovered at the last minute that we didn't have all
4874 of the appropriate copyright paperwork. We are working with AMD to
4875 resolve this, and hope to have it available soon.
4879 We have sped up the remote serial line protocol, especially for targets
4880 with lots of registers. It now supports a new `expedited status' ('T')
4881 message which can be used in place of the existing 'S' status message.
4882 This allows the remote stub to send only the registers that GDB
4883 needs to make a quick decision about single-stepping or conditional
4884 breakpoints, eliminating the need to fetch the entire register set for
4885 each instruction being stepped through.
4887 The GDB remote serial protocol now implements a write-through cache for
4888 registers, only re-reading the registers if the target has run.
4890 There is also a new remote serial stub for SPARC processors. You can
4891 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4892 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4893 processor with a serial port.
4897 Configure.in files have become much easier to read and modify. A new
4898 `table driven' format makes it more obvious what configurations are
4899 supported, and what files each one uses.
4903 There is a new opcodes library which will eventually contain all of the
4904 disassembly routines and opcode tables. At present, it only contains
4905 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4906 disassembler (binutils/objdump) to share these routines.
4908 The libiberty library is now copylefted under the GNU Library General
4909 Public License. This allows more liberal use, and was done so libg++
4910 can use it. This makes no difference to GDB, since the Library License
4911 grants all the rights from the General Public License.
4915 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4916 reference to the stabs symbol info used by the debugger. It is (as far
4917 as we know) the only published document on this fascinating topic. We
4918 encourage you to read it, compare it to the stabs information on your
4919 system, and send improvements on the document in general (to
4920 bug-gdb@prep.ai.mit.edu).
4922 And, of course, many bugs have been fixed.
4925 *** Changes in GDB-4.6:
4927 * Better support for C++ function names
4929 GDB now accepts as input the "demangled form" of C++ overloaded function
4930 names and member function names, and can do command completion on such names
4931 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4932 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4933 Make use of command completion, it is your friend.
4935 GDB also now accepts a variety of C++ mangled symbol formats. They are
4936 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4937 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4938 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4939 for the list of formats.
4941 * G++ symbol mangling problem
4943 Recent versions of gcc have a bug in how they emit debugging information for
4944 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4945 directory) can be applied to gcc to fix the problem. Alternatively, if you
4946 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4947 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4948 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4951 * New 'maintenance' command
4953 All of the commands related to hacking GDB internals have been moved out of
4954 the main command set, and now live behind the 'maintenance' command. This
4955 can also be abbreviated as 'mt'. The following changes were made:
4957 dump-me -> maintenance dump-me
4958 info all-breakpoints -> maintenance info breakpoints
4959 printmsyms -> maintenance print msyms
4960 printobjfiles -> maintenance print objfiles
4961 printpsyms -> maintenance print psymbols
4962 printsyms -> maintenance print symbols
4964 The following commands are new:
4966 maintenance demangle Call internal GDB demangler routine to
4967 demangle a C++ link name and prints the result.
4968 maintenance print type Print a type chain for a given symbol
4970 * Change to .gdbinit file processing
4972 We now read the $HOME/.gdbinit file before processing the argv arguments
4973 (e.g. reading symbol files or core files). This allows global parameters to
4974 be set, which will apply during the symbol reading. The ./.gdbinit is still
4975 read after argv processing.
4977 * New hosts supported
4979 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4981 GNU/Linux support i386-unknown-linux or linux
4983 We are also including code to support the HP/PA running BSD and HPUX. This
4984 is almost guaranteed not to work, as we didn't have time to test or build it
4985 for this release. We are including it so that the more adventurous (or
4986 masochistic) of you can play with it. We also had major problems with the
4987 fact that the compiler that we got from HP doesn't support the -g option.
4990 * New targets supported
4992 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4994 * More smarts about finding #include files
4996 GDB now remembers the compilation directory for all include files, and for
4997 all files from which C is generated (like yacc and lex sources). This
4998 greatly improves GDB's ability to find yacc/lex sources, and include files,
4999 especially if you are debugging your program from a directory different from
5000 the one that contains your sources.
5002 We also fixed a bug which caused difficulty with listing and setting
5003 breakpoints in include files which contain C code. (In the past, you had to
5004 try twice in order to list an include file that you hadn't looked at before.)
5006 * Interesting infernals change
5008 GDB now deals with arbitrary numbers of sections, where the symbols for each
5009 section must be relocated relative to that section's landing place in the
5010 target's address space. This work was needed to support ELF with embedded
5011 stabs used by Solaris-2.0.
5013 * Bug fixes (of course!)
5015 There have been loads of fixes for the following things:
5016 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
5017 i960, stabs, DOS(GO32), procfs, etc...
5019 See the ChangeLog for details.
5021 *** Changes in GDB-4.5:
5023 * New machines supported (host and target)
5025 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
5027 SGI Irix-4.x mips-sgi-irix4 or iris4
5029 * New malloc package
5031 GDB now uses a new memory manager called mmalloc, based on gmalloc.
5032 Mmalloc is capable of handling mutiple heaps of memory. It is also
5033 capable of saving a heap to a file, and then mapping it back in later.
5034 This can be used to greatly speedup the startup of GDB by using a
5035 pre-parsed symbol table which lives in a mmalloc managed heap. For
5036 more details, please read mmalloc/mmalloc.texi.
5040 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
5041 'help info proc' for details.
5043 * MIPS ecoff symbol table format
5045 The code that reads MIPS symbol table format is now supported on all hosts.
5046 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
5049 * File name changes for MS-DOS
5051 Many files in the config directories have been renamed to make it easier to
5052 support GDB on MS-DOSe systems (which have very restrictive file name
5053 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5054 environment) is close to working but has some remaining problems. Note
5055 that debugging of DOS programs is not supported, due to limitations
5056 in the ``operating system'', but it can be used to host cross-debugging.
5058 * Cross byte order fixes
5060 Many fixes have been made to support cross debugging of Sparc and MIPS
5061 targets from hosts whose byte order differs.
5063 * New -mapped and -readnow options
5065 If memory-mapped files are available on your system through the 'mmap'
5066 system call, you can use the -mapped option on the `file' or
5067 `symbol-file' commands to cause GDB to write the symbols from your
5068 program into a reusable file. If the program you are debugging is
5069 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5070 Future GDB debugging sessions will notice the presence of this file,
5071 and will quickly map in symbol information from it, rather than reading
5072 the symbol table from the executable program. Using the '-mapped'
5073 option in a GDB `file' or `symbol-file' command has the same effect as
5074 starting GDB with the '-mapped' command-line option.
5076 You can cause GDB to read the entire symbol table immediately by using
5077 the '-readnow' option with any of the commands that load symbol table
5078 information (or on the GDB command line). This makes the command
5079 slower, but makes future operations faster.
5081 The -mapped and -readnow options are typically combined in order to
5082 build a `fred.syms' file that contains complete symbol information.
5083 A simple GDB invocation to do nothing but build a `.syms' file for future
5086 gdb -batch -nx -mapped -readnow programname
5088 The `.syms' file is specific to the host machine on which GDB is run.
5089 It holds an exact image of GDB's internal symbol table. It cannot be
5090 shared across multiple host platforms.
5092 * longjmp() handling
5094 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5095 siglongjmp() without losing control. This feature has not yet been ported to
5096 all systems. It currently works on many 386 platforms, all MIPS-based
5097 platforms (SGI, DECstation, etc), and Sun3/4.
5101 Preliminary work has been put in to support the new Solaris OS from Sun. At
5102 this time, it can control and debug processes, but it is not capable of
5107 As always, many many bug fixes. The major areas were with g++, and mipsread.
5108 People using the MIPS-based platforms should experience fewer mysterious
5109 crashes and trashed symbol tables.
5111 *** Changes in GDB-4.4:
5113 * New machines supported (host and target)
5115 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5117 BSD Reno on Vax vax-dec-bsd
5118 Ultrix on Vax vax-dec-ultrix
5120 * New machines supported (target)
5122 AMD 29000 embedded, using EBMON a29k-none-none
5126 GDB continues to improve its handling of C++. `References' work better.
5127 The demangler has also been improved, and now deals with symbols mangled as
5128 per the Annotated C++ Reference Guide.
5130 GDB also now handles `stabs' symbol information embedded in MIPS
5131 `ecoff' symbol tables. Since the ecoff format was not easily
5132 extensible to handle new languages such as C++, this appeared to be a
5133 good way to put C++ debugging info into MIPS binaries. This option
5134 will be supported in the GNU C compiler, version 2, when it is
5137 * New features for SVR4
5139 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5140 shared libraries. Debugging dynamically linked programs should present
5141 only minor differences from debugging statically linked programs.
5143 The `info proc' command will print out information about any process
5144 on an SVR4 system (including the one you are debugging). At the moment,
5145 it prints the address mappings of the process.
5147 If you bring up GDB on another SVR4 system, please send mail to
5148 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5150 * Better dynamic linking support in SunOS
5152 Reading symbols from shared libraries which contain debugging symbols
5153 now works properly. However, there remain issues such as automatic
5154 skipping of `transfer vector' code during function calls, which
5155 make it harder to debug code in a shared library, than to debug the
5156 same code linked statically.
5160 GDB is now using the latest `getopt' routines from the FSF. This
5161 version accepts the -- prefix for options with long names. GDB will
5162 continue to accept the old forms (-option and +option) as well.
5163 Various single letter abbreviations for options have been explicity
5164 added to the option table so that they won't get overshadowed in the
5165 future by other options that begin with the same letter.
5169 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5170 Many assorted bugs have been handled. Many more remain to be handled.
5171 See the various ChangeLog files (primarily in gdb and bfd) for details.
5174 *** Changes in GDB-4.3:
5176 * New machines supported (host and target)
5178 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5179 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5180 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5182 * Almost SCO Unix support
5184 We had hoped to support:
5185 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5186 (except for core file support), but we discovered very late in the release
5187 that it has problems with process groups that render gdb unusable. Sorry
5188 about that. I encourage people to fix it and post the fixes.
5190 * Preliminary ELF and DWARF support
5192 GDB can read ELF object files on System V Release 4, and can handle
5193 debugging records for C, in DWARF format, in ELF files. This support
5194 is preliminary. If you bring up GDB on another SVR4 system, please
5195 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5200 GDB now uses the latest `readline' library. One user-visible change
5201 is that two tabs will list possible command completions, which previously
5202 required typing M-? (meta-question mark, or ESC ?).
5206 The `stepi' bug that many of you noticed has been squashed.
5207 Many bugs in C++ have been handled. Many more remain to be handled.
5208 See the various ChangeLog files (primarily in gdb and bfd) for details.
5210 * State of the MIPS world (in case you wondered):
5212 GDB can understand the symbol tables emitted by the compilers
5213 supplied by most vendors of MIPS-based machines, including DEC. These
5214 symbol tables are in a format that essentially nobody else uses.
5216 Some versions of gcc come with an assembler post-processor called
5217 mips-tfile. This program is required if you want to do source-level
5218 debugging of gcc-compiled programs. I believe FSF does not ship
5219 mips-tfile with gcc version 1, but it will eventually come with gcc
5222 Debugging of g++ output remains a problem. g++ version 1.xx does not
5223 really support it at all. (If you're lucky, you should be able to get
5224 line numbers and stack traces to work, but no parameters or local
5225 variables.) With some work it should be possible to improve the
5228 When gcc version 2 is released, you will have somewhat better luck.
5229 However, even then you will get confusing results for inheritance and
5232 We will eventually provide full debugging of g++ output on
5233 DECstations. This will probably involve some kind of stabs-in-ecoff
5234 encapulation, but the details have not been worked out yet.
5237 *** Changes in GDB-4.2:
5239 * Improved configuration
5241 Only one copy of `configure' exists now, and it is not self-modifying.
5242 Porting BFD is simpler.
5246 The `step' and `next' commands now only stop at the first instruction
5247 of a source line. This prevents the multiple stops that used to occur
5248 in switch statements, for-loops, etc. `Step' continues to stop if a
5249 function that has debugging information is called within the line.
5253 Lots of small bugs fixed. More remain.
5255 * New host supported (not target)
5257 Intel 386 PC clone running Mach i386-none-mach
5260 *** Changes in GDB-4.1:
5262 * Multiple source language support
5264 GDB now has internal scaffolding to handle several source languages.
5265 It determines the type of each source file from its filename extension,
5266 and will switch expression parsing and number formatting to match the
5267 language of the function in the currently selected stack frame.
5268 You can also specifically set the language to be used, with
5269 `set language c' or `set language modula-2'.
5273 GDB now has preliminary support for the GNU Modula-2 compiler,
5274 currently under development at the State University of New York at
5275 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5276 continue through the fall of 1991 and into 1992.
5278 Other Modula-2 compilers are currently not supported, and attempting to
5279 debug programs compiled with them will likely result in an error as the
5280 symbol table is read. Feel free to work on it, though!
5282 There are hooks in GDB for strict type checking and range checking,
5283 in the `Modula-2 philosophy', but they do not currently work.
5287 GDB can now write to executable and core files (e.g. patch
5288 a variable's value). You must turn this switch on, specify
5289 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5290 by assigning a new value to a variable. Modifications take
5293 * Automatic SunOS shared library reading
5295 When you run your program, GDB automatically determines where its
5296 shared libraries (if any) have been loaded, and reads their symbols.
5297 The `share' command is no longer needed. This also works when
5298 examining core files.
5302 You can specify the number of lines that the `list' command shows.
5305 * New machines supported (host and target)
5307 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5308 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5309 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5311 * New hosts supported (not targets)
5313 IBM RT/PC: romp-ibm-aix or rtpc
5315 * New targets supported (not hosts)
5317 AMD 29000 embedded with COFF a29k-none-coff
5318 AMD 29000 embedded with a.out a29k-none-aout
5319 Ultracomputer remote kernel debug a29k-nyu-kern
5321 * New remote interfaces
5327 *** Changes in GDB-4.0:
5331 Wide output is wrapped at good places to make the output more readable.
5333 Gdb now supports cross-debugging from a host machine of one type to a
5334 target machine of another type. Communication with the target system
5335 is over serial lines. The ``target'' command handles connecting to the
5336 remote system; the ``load'' command will download a program into the
5337 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5338 also supports debugging of realtime processes running under VxWorks,
5339 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5340 stub on the target system.
5342 New CPUs supported include the AMD 29000 and Intel 960.
5344 GDB now reads object files and symbol tables via a ``binary file''
5345 library, which allows a single copy of GDB to debug programs of multiple
5346 object file types such as a.out and coff.
5348 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5349 refcard.dvi and refcard.ps are available to format it).
5352 * Control-Variable user interface simplified
5354 All variables that control the operation of the debugger can be set
5355 by the ``set'' command, and displayed by the ``show'' command.
5357 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5358 ``Show prompt'' produces the response:
5359 Gdb's prompt is new-gdb=>.
5361 What follows are the NEW set commands. The command ``help set'' will
5362 print a complete list of old and new set commands. ``help set FOO''
5363 will give a longer description of the variable FOO. ``show'' will show
5364 all of the variable descriptions and their current settings.
5366 confirm on/off: Enables warning questions for operations that are
5367 hard to recover from, e.g. rerunning the program while
5368 it is already running. Default is ON.
5370 editing on/off: Enables EMACS style command line editing
5371 of input. Previous lines can be recalled with
5372 control-P, the current line can be edited with control-B,
5373 you can search for commands with control-R, etc.
5376 history filename NAME: NAME is where the gdb command history
5377 will be stored. The default is .gdb_history,
5378 or the value of the environment variable
5381 history size N: The size, in commands, of the command history. The
5382 default is 256, or the value of the environment variable
5385 history save on/off: If this value is set to ON, the history file will
5386 be saved after exiting gdb. If set to OFF, the
5387 file will not be saved. The default is OFF.
5389 history expansion on/off: If this value is set to ON, then csh-like
5390 history expansion will be performed on
5391 command line input. The default is OFF.
5393 radix N: Sets the default radix for input and output. It can be set
5394 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5395 in the current radix, so "set radix 10" is always a no-op.
5397 height N: This integer value is the number of lines on a page. Default
5398 is 24, the current `stty rows'' setting, or the ``li#''
5399 setting from the termcap entry matching the environment
5402 width N: This integer value is the number of characters on a line.
5403 Default is 80, the current `stty cols'' setting, or the ``co#''
5404 setting from the termcap entry matching the environment
5407 Note: ``set screensize'' is obsolete. Use ``set height'' and
5408 ``set width'' instead.
5410 print address on/off: Print memory addresses in various command displays,
5411 such as stack traces and structure values. Gdb looks
5412 more ``symbolic'' if you turn this off; it looks more
5413 ``machine level'' with it on. Default is ON.
5415 print array on/off: Prettyprint arrays. New convenient format! Default
5418 print demangle on/off: Print C++ symbols in "source" form if on,
5421 print asm-demangle on/off: Same, for assembler level printouts
5424 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5427 * Support for Epoch Environment.
5429 The epoch environment is a version of Emacs v18 with windowing. One
5430 new command, ``inspect'', is identical to ``print'', except that if you
5431 are running in the epoch environment, the value is printed in its own
5435 * Support for Shared Libraries
5437 GDB can now debug programs and core files that use SunOS shared libraries.
5438 Symbols from a shared library cannot be referenced
5439 before the shared library has been linked with the program (this
5440 happens after you type ``run'' and before the function main() is entered).
5441 At any time after this linking (including when examining core files
5442 from dynamically linked programs), gdb reads the symbols from each
5443 shared library when you type the ``sharedlibrary'' command.
5444 It can be abbreviated ``share''.
5446 sharedlibrary REGEXP: Load shared object library symbols for files
5447 matching a unix regular expression. No argument
5448 indicates to load symbols for all shared libraries.
5450 info sharedlibrary: Status of loaded shared libraries.
5455 A watchpoint stops execution of a program whenever the value of an
5456 expression changes. Checking for this slows down execution
5457 tremendously whenever you are in the scope of the expression, but is
5458 quite useful for catching tough ``bit-spreader'' or pointer misuse
5459 problems. Some machines such as the 386 have hardware for doing this
5460 more quickly, and future versions of gdb will use this hardware.
5462 watch EXP: Set a watchpoint (breakpoint) for an expression.
5464 info watchpoints: Information about your watchpoints.
5466 delete N: Deletes watchpoint number N (same as breakpoints).
5467 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5468 enable N: Re-enables watchpoint number N (same as breakpoints).
5471 * C++ multiple inheritance
5473 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5476 * C++ exception handling
5478 Gdb now supports limited C++ exception handling. Besides the existing
5479 ability to breakpoint on an exception handler, gdb can breakpoint on
5480 the raising of an exception (before the stack is peeled back to the
5483 catch FOO: If there is a FOO exception handler in the dynamic scope,
5484 set a breakpoint to catch exceptions which may be raised there.
5485 Multiple exceptions (``catch foo bar baz'') may be caught.
5487 info catch: Lists all exceptions which may be caught in the
5488 current stack frame.
5491 * Minor command changes
5493 The command ``call func (arg, arg, ...)'' now acts like the print
5494 command, except it does not print or save a value if the function's result
5495 is void. This is similar to dbx usage.
5497 The ``up'' and ``down'' commands now always print the frame they end up
5498 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5499 frames without printing.
5501 * New directory command
5503 'dir' now adds directories to the FRONT of the source search path.
5504 The path starts off empty. Source files that contain debug information
5505 about the directory in which they were compiled can be found even
5506 with an empty path; Sun CC and GCC include this information. If GDB can't
5507 find your source file in the current directory, type "dir .".
5509 * Configuring GDB for compilation
5511 For normal use, type ``./configure host''. See README or gdb.texinfo
5514 GDB now handles cross debugging. If you are remotely debugging between
5515 two different machines, type ``./configure host -target=targ''.
5516 Host is the machine where GDB will run; targ is the machine
5517 where the program that you are debugging will run.