1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
8 Display the details of GDB configure-time options.
10 maint set|show per-command
11 maint set|show per-command space
12 maint set|show per-command time
13 maint set|show per-command symtab
14 Enable display of per-command gdb resource usage.
18 set remote trace-status-packet
19 show remote trace-status-packet
20 Set/show the use of remote protocol qTStatus packet.
22 * New command-line options
24 Display the details of GDB configure-time options.
26 * The command 'tsave' can now support new option '-ctf' to save trace
27 buffer in Common Trace Format.
29 * Newly installed $prefix/bin/gcore acts as a shell interface for the
34 ** The -trace-save MI command can optionally save trace buffer in Common
37 *** Changes in GDB 7.6
39 * Target record has been renamed to record-full.
40 Record/replay is now enabled with the "record full" command.
41 This also affects settings that are associated with full record/replay
42 that have been moved from "set/show record" to "set/show record full":
44 set|show record full insn-number-max
45 set|show record full stop-at-limit
46 set|show record full memory-query
48 * A new record target "record-btrace" has been added. The new target
49 uses hardware support to record the control-flow of a process. It
50 does not support replaying the execution, but it implements the
51 below new commands for investigating the recorded execution log.
52 This new recording method can be enabled using:
56 The "record-btrace" target is only available on Intel Atom processors
57 and requires a Linux kernel 2.6.32 or later.
59 * Two new commands have been added for record/replay to give information
60 about the recorded execution without having to replay the execution.
61 The commands are only supported by "record btrace".
63 record instruction-history prints the execution history at
64 instruction granularity
66 record function-call-history prints the execution history at
69 * New native configurations
71 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
72 FreeBSD/powerpc powerpc*-*-freebsd
73 x86_64/Cygwin x86_64-*-cygwin*
74 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
78 ARM AArch64 aarch64*-*-elf
79 ARM AArch64 GNU/Linux aarch64*-*-linux
80 Lynx 178 PowerPC powerpc-*-lynx*178
81 x86_64/Cygwin x86_64-*-cygwin*
82 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
84 * If the configured location of system.gdbinit file (as given by the
85 --with-system-gdbinit option at configure time) is in the
86 data-directory (as specified by --with-gdb-datadir at configure
87 time) or in one of its subdirectories, then GDB will look for the
88 system-wide init file in the directory specified by the
89 --data-directory command-line option.
91 * New command line options:
93 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
94 other initialization files, unlike -nx which disables all of them.
96 * Removed command line options
98 -epoch This was used by the gdb mode in Epoch, an ancient fork of
101 * The 'ptype' and 'whatis' commands now accept an argument to control
104 * 'info proc' now works on some core files.
108 ** Vectors can be created with gdb.Type.vector.
110 ** Python's atexit.register now works in GDB.
112 ** Types can be pretty-printed via a Python API.
114 ** Python 3 is now supported (in addition to Python 2.4 or later)
116 ** New class gdb.Architecture exposes GDB's internal representation
117 of architecture in the Python API.
119 ** New method Frame.architecture returns the gdb.Architecture object
120 corresponding to the frame's architecture.
122 * New Python-based convenience functions:
124 ** $_memeq(buf1, buf2, length)
125 ** $_streq(str1, str2)
127 ** $_regex(str, regex)
129 * The 'cd' command now defaults to using '~' (the home directory) if not
132 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
133 default for GCC since November 2000.
135 * The command 'forward-search' can now be abbreviated as 'fo'.
137 * The command 'info tracepoints' can now display 'installed on target'
138 or 'not installed on target' for each non-pending location of tracepoint.
140 * New configure options
142 --enable-libmcheck/--disable-libmcheck
143 By default, development versions are built with -lmcheck on hosts
144 that support it, in order to help track memory corruption issues.
145 Release versions, on the other hand, are built without -lmcheck
146 by default. The --enable-libmcheck/--disable-libmcheck configure
147 options allow the user to override that default.
148 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
149 This configure option allows the user to build GDB with
150 libbabeltrace using which GDB can read Common Trace Format data.
152 * New commands (for set/show, see "New options" below)
155 Catch signals. This is similar to "handle", but allows commands and
156 conditions to be attached.
159 List the BFDs known to GDB.
161 python-interactive [command]
163 Start a Python interactive prompt, or evaluate the optional command
164 and print the result of expressions.
167 "py" is a new alias for "python".
169 enable type-printer [name]...
170 disable type-printer [name]...
171 Enable or disable type printers.
175 ** For the Renesas Super-H architecture, the "regs" command has been removed
176 (has been deprecated in GDB 7.5), and "info all-registers" should be used
181 set print type methods (on|off)
182 show print type methods
183 Control whether method declarations are displayed by "ptype".
184 The default is to show them.
186 set print type typedefs (on|off)
187 show print type typedefs
188 Control whether typedef definitions are displayed by "ptype".
189 The default is to show them.
191 set filename-display basename|relative|absolute
192 show filename-display
193 Control the way in which filenames is displayed.
194 The default is "relative", which preserves previous behavior.
196 set trace-buffer-size
197 show trace-buffer-size
198 Request target to change the size of trace buffer.
200 set remote trace-buffer-size-packet auto|on|off
201 show remote trace-buffer-size-packet
202 Control the use of the remote protocol `QTBuffer:size' packet.
206 Control display of debugging messages related to ARM AArch64.
209 set debug coff-pe-read
210 show debug coff-pe-read
211 Control display of debugging messages related to reading of COFF/PE
216 Control display of debugging messages related to Mach-O symbols
219 set debug notification
220 show debug notification
221 Control display of debugging info for async remote notification.
225 ** Command parameter changes are now notified using new async record
226 "=cmd-param-changed".
227 ** Trace frame changes caused by command "tfind" are now notified using
228 new async record "=traceframe-changed".
229 ** The creation, deletion and modification of trace state variables
230 are now notified using new async records "=tsv-created",
231 "=tsv-deleted" and "=tsv-modified".
232 ** The start and stop of process record are now notified using new
233 async record "=record-started" and "=record-stopped".
234 ** Memory changes are now notified using new async record
236 ** The data-disassemble command response will include a "fullname" field
237 containing the absolute file name when source has been requested.
238 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
239 command, to allow pattern filling of memory areas.
240 ** New commands "-catch-load"/"-catch-unload" added for intercepting
241 library load/unload events.
242 ** The response to breakpoint commands and breakpoint async records
243 includes an "installed" field containing a boolean state about each
244 non-pending tracepoint location is whether installed on target or not.
245 ** Output of the "-trace-status" command includes a "trace-file" field
246 containing the name of the trace file being examined. This field is
247 optional, and only present when examining a trace file.
248 ** The "fullname" field is now always present along with the "file" field,
249 even if the file cannot be found by GDB.
251 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
252 You must have the LZMA library available when configuring GDB for this
253 feature to be enabled. For more information, see:
254 http://fedoraproject.org/wiki/Features/MiniDebugInfo
259 Set the size of trace buffer. The remote stub reports support for this
260 packet to gdb's qSupported query.
263 Enable Branch Trace Store (BTS)-based branch tracing for the current
264 thread. The remote stub reports support for this packet to gdb's
268 Disable branch tracing for the current thread. The remote stub reports
269 support for this packet to gdb's qSupported query.
272 Read the traced branches for the current thread. The remote stub
273 reports support for this packet to gdb's qSupported query.
275 *** Changes in GDB 7.5
277 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
278 for more x32 ABI info.
280 * GDB now supports access to MIPS DSP registers on Linux targets.
282 * GDB now supports debugging microMIPS binaries.
284 * The "info os" command on GNU/Linux can now display information on
285 several new classes of objects managed by the operating system:
286 "info os procgroups" lists process groups
287 "info os files" lists file descriptors
288 "info os sockets" lists internet-domain sockets
289 "info os shm" lists shared-memory regions
290 "info os semaphores" lists semaphores
291 "info os msg" lists message queues
292 "info os modules" lists loaded kernel modules
294 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
295 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
296 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
297 options and inspect the probe arguments using the new $_probe_arg family
298 of convenience variables. You can obtain more information about SystemTap
299 in <http://sourceware.org/systemtap/>.
301 * GDB now supports reversible debugging on ARM, it allows you to
302 debug basic ARM and THUMB instructions, and provides
303 record/replay support.
305 * The option "symbol-reloading" has been deleted as it is no longer used.
309 ** GDB commands implemented in Python can now be put in command class
312 ** The "maint set python print-stack on|off" is now deleted.
314 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
315 apply "flag enum"-style pretty-printing to any enum.
317 ** gdb.lookup_symbol can now work when there is no current frame.
319 ** gdb.Symbol now has a 'line' attribute, holding the line number in
320 the source at which the symbol was defined.
322 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
323 method 'value'. The former indicates whether the symbol needs a
324 frame in order to compute its value, and the latter computes the
327 ** A new method 'referenced_value' on gdb.Value objects which can
328 dereference pointer as well as C++ reference values.
330 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
331 which return the global and static blocks (as gdb.Block objects),
332 of the underlying symbol table, respectively.
334 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
335 object associated with a PC value.
337 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
338 of the address range occupied by code for the current source line.
340 * Go language support.
341 GDB now supports debugging programs written in the Go programming
344 * GDBserver now supports stdio connections.
345 E.g. (gdb) target remote | ssh myhost gdbserver - hello
347 * The binary "gdbtui" can no longer be built or installed.
348 Use "gdb -tui" instead.
350 * GDB will now print "flag" enums specially. A flag enum is one where
351 all the enumerator values have no bits in common when pairwise
352 "and"ed. When printing a value whose type is a flag enum, GDB will
353 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
354 (gdb) print (enum E) 3
357 * The filename part of a linespec will now match trailing components
358 of a source file name. For example, "break gcc/expr.c:1000" will
359 now set a breakpoint in build/gcc/expr.c, but not
362 * The "info proc" and "generate-core-file" commands will now also
363 work on remote targets connected to GDBserver on Linux.
365 * The command "info catch" has been removed. It has been disabled
368 * The "catch exception" and "catch assert" commands now accept
369 a condition at the end of the command, much like the "break"
370 command does. For instance:
372 (gdb) catch exception Constraint_Error if Barrier = True
374 Previously, it was possible to add a condition to such catchpoints,
375 but it had to be done as a second step, after the catchpoint had been
376 created, using the "condition" command.
378 * The "info static-tracepoint-marker" command will now also work on
379 native Linux targets with in-process agent.
381 * GDB can now set breakpoints on inlined functions.
383 * The .gdb_index section has been updated to include symbols for
384 inlined functions. GDB will ignore older .gdb_index sections by
385 default, which could cause symbol files to be loaded more slowly
386 until their .gdb_index sections can be recreated. The new command
387 "set use-deprecated-index-sections on" will cause GDB to use any older
388 .gdb_index sections it finds. This will restore performance, but the
389 ability to set breakpoints on inlined functions will be lost in symbol
390 files with older .gdb_index sections.
392 The .gdb_index section has also been updated to record more information
393 about each symbol. This speeds up the "info variables", "info functions"
394 and "info types" commands when used with programs having the .gdb_index
395 section, as well as speeding up debugging with shared libraries using
396 the .gdb_index section.
398 * Ada support for GDB/MI Variable Objects has been added.
400 * GDB can now support 'breakpoint always-inserted mode' in 'record'
405 ** New command -info-os is the MI equivalent of "info os".
407 ** Output logs ("set logging" and related) now include MI output.
411 ** "set use-deprecated-index-sections on|off"
412 "show use-deprecated-index-sections on|off"
413 Controls the use of deprecated .gdb_index sections.
415 ** "catch load" and "catch unload" can be used to stop when a shared
416 library is loaded or unloaded, respectively.
418 ** "enable count" can be used to auto-disable a breakpoint after
421 ** "info vtbl" can be used to show the virtual method tables for
422 C++ and Java objects.
424 ** "explore" and its sub commands "explore value" and "explore type"
425 can be used to reccursively explore values and types of
426 expressions. These commands are available only if GDB is
427 configured with '--with-python'.
429 ** "info auto-load" shows status of all kinds of auto-loaded files,
430 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
431 sequences of commands files, "info auto-load python-scripts"
432 shows status of auto-loading Python script files,
433 "info auto-load local-gdbinit" shows status of loading init file
434 (.gdbinit) from current directory and "info auto-load libthread-db" shows
435 status of inferior specific thread debugging shared library loading.
437 ** "info auto-load-scripts", "set auto-load-scripts on|off"
438 and "show auto-load-scripts" commands have been deprecated, use their
439 "info auto-load python-scripts", "set auto-load python-scripts on|off"
440 and "show auto-load python-scripts" counterparts instead.
442 ** "dprintf location,format,args..." creates a dynamic printf, which
443 is basically a breakpoint that does a printf and immediately
444 resumes your program's execution, so it is like a printf that you
445 can insert dynamically at runtime instead of at compiletime.
447 ** "set print symbol"
449 Controls whether GDB attempts to display the symbol, if any,
450 corresponding to addresses it prints. This defaults to "on", but
451 you can set it to "off" to restore GDB's previous behavior.
453 * Deprecated commands
455 ** For the Renesas Super-H architecture, the "regs" command has been
456 deprecated, and "info all-registers" should be used instead.
460 Renesas RL78 rl78-*-elf
461 HP OpenVMS ia64 ia64-hp-openvms*
463 * GDBserver supports evaluation of breakpoint conditions. When
464 support is advertised by GDBserver, GDB may be told to send the
465 breakpoint conditions in bytecode form to GDBserver. GDBserver
466 will only report the breakpoint trigger to GDB when its condition
472 show mips compression
473 Select the compressed ISA encoding used in functions that have no symbol
474 information available. The encoding can be set to either of:
477 and is updated automatically from ELF file flags if available.
479 set breakpoint condition-evaluation
480 show breakpoint condition-evaluation
481 Control whether breakpoint conditions are evaluated by GDB ("host") or by
482 GDBserver ("target"). Default option "auto" chooses the most efficient
484 This option can improve debugger efficiency depending on the speed of the
488 Disable auto-loading globally.
491 Show auto-loading setting of all kinds of auto-loaded files.
493 set auto-load gdb-scripts on|off
494 show auto-load gdb-scripts
495 Control auto-loading of GDB canned sequences of commands files.
497 set auto-load python-scripts on|off
498 show auto-load python-scripts
499 Control auto-loading of Python script files.
501 set auto-load local-gdbinit on|off
502 show auto-load local-gdbinit
503 Control loading of init file (.gdbinit) from current directory.
505 set auto-load libthread-db on|off
506 show auto-load libthread-db
507 Control auto-loading of inferior specific thread debugging shared library.
509 set auto-load scripts-directory <dir1>[:<dir2>...]
510 show auto-load scripts-directory
511 Set a list of directories from which to load auto-loaded scripts.
512 Automatically loaded Python scripts and GDB scripts are located in one
513 of the directories listed by this option.
514 The delimiter (':' above) may differ according to the host platform.
516 set auto-load safe-path <dir1>[:<dir2>...]
517 show auto-load safe-path
518 Set a list of directories from which it is safe to auto-load files.
519 The delimiter (':' above) may differ according to the host platform.
521 set debug auto-load on|off
523 Control display of debugging info for auto-loading the files above.
525 set dprintf-style gdb|call|agent
527 Control the way in which a dynamic printf is performed; "gdb"
528 requests a GDB printf command, while "call" causes dprintf to call a
529 function in the inferior. "agent" requests that the target agent
530 (such as GDBserver) do the printing.
532 set dprintf-function <expr>
533 show dprintf-function
534 set dprintf-channel <expr>
536 Set the function and optional first argument to the call when using
537 the "call" style of dynamic printf.
539 set disconnected-dprintf on|off
540 show disconnected-dprintf
541 Control whether agent-style dynamic printfs continue to be in effect
542 after GDB disconnects.
544 * New configure options
547 Configure default value for the 'set auto-load scripts-directory'
548 setting above. It defaults to '$debugdir:$datadir/auto-load',
549 $debugdir representing global debugging info directories (available
550 via 'show debug-file-directory') and $datadir representing GDB's data
551 directory (available via 'show data-directory').
553 --with-auto-load-safe-path
554 Configure default value for the 'set auto-load safe-path' setting
555 above. It defaults to the --with-auto-load-dir setting.
557 --without-auto-load-safe-path
558 Set 'set auto-load safe-path' to '/', effectively disabling this
563 z0/z1 conditional breakpoints extension
565 The z0/z1 breakpoint insertion packets have been extended to carry
566 a list of conditional expressions over to the remote stub depending on the
567 condition evaluation mode. The use of this extension can be controlled
568 via the "set remote conditional-breakpoints-packet" command.
572 Specify the signals which the remote stub may pass to the debugged
573 program without GDB involvement.
575 * New command line options
577 --init-command=FILE, -ix Like --command, -x but execute it
578 before loading inferior.
579 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
580 execute it before loading inferior.
582 *** Changes in GDB 7.4
584 * GDB now handles ambiguous linespecs more consistently; the existing
585 FILE:LINE support has been expanded to other types of linespecs. A
586 breakpoint will now be set on all matching locations in all
587 inferiors, and locations will be added or removed according to
590 * GDB now allows you to skip uninteresting functions and files when
591 stepping with the "skip function" and "skip file" commands.
593 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
594 and "show remote hardware-watchpoint-length-limit". These allows to
595 set or show the maximum length limit (in bytes) of a remote
596 target hardware watchpoint.
598 This allows e.g. to use "unlimited" hardware watchpoints with the
599 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
600 watchpoints are slower than real hardware watchpoints but are
601 significantly faster than gdb software watchpoints.
605 ** The register_pretty_printer function in module gdb.printing now takes
606 an optional `replace' argument. If True, the new printer replaces any
609 ** The "maint set python print-stack on|off" command has been
610 deprecated and will be deleted in GDB 7.5.
611 A new command: "set python print-stack none|full|message" has
612 replaced it. Additionally, the default for "print-stack" is
613 now "message", which just prints the error message without
616 ** A prompt substitution hook (prompt_hook) is now available to the
619 ** A new Python module, gdb.prompt has been added to the GDB Python
620 modules library. This module provides functionality for
621 escape sequences in prompts (used by set/show
622 extended-prompt). These escape sequences are replaced by their
625 ** Python commands and convenience-functions located in
626 'data-directory'/python/gdb/command and
627 'data-directory'/python/gdb/function are now automatically loaded
630 ** Blocks now provide four new attributes. global_block and
631 static_block will return the global and static blocks
632 respectively. is_static and is_global are boolean attributes
633 that indicate if the block is one of those two types.
635 ** Symbols now provide the "type" attribute, the type of the symbol.
637 ** The "gdb.breakpoint" function has been deprecated in favor of
640 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
641 of a function. This class is based on the "finish" command
642 available in the CLI.
644 ** Type objects for struct and union types now allow access to
645 the fields using standard Python dictionary (mapping) methods.
646 For example, "some_type['myfield']" now works, as does
649 ** A new event "gdb.new_objfile" has been added, triggered by loading a
652 ** A new function, "deep_items" has been added to the gdb.types
653 module in the GDB Python modules library. This function returns
654 an iterator over the fields of a struct or union type. Unlike
655 the standard Python "iteritems" method, it will recursively traverse
656 any anonymous fields.
660 ** "*stopped" events can report several new "reason"s, such as
663 ** Breakpoint changes are now notified using new async records, like
664 "=breakpoint-modified".
666 ** New command -ada-task-info.
668 * libthread-db-search-path now supports two special values: $sdir and $pdir.
669 $sdir specifies the default system locations of shared libraries.
670 $pdir specifies the directory where the libpthread used by the application
673 GDB no longer looks in $sdir and $pdir after it has searched the directories
674 mentioned in libthread-db-search-path. If you want to search those
675 directories, they must be specified in libthread-db-search-path.
676 The default value of libthread-db-search-path on GNU/Linux and Solaris
677 systems is now "$sdir:$pdir".
679 $pdir is not supported by gdbserver, it is currently ignored.
680 $sdir is supported by gdbserver.
682 * New configure option --with-iconv-bin.
683 When using the internationalization support like the one in the GNU C
684 library, GDB will invoke the "iconv" program to get a list of supported
685 character sets. If this program lives in a non-standard location, one can
686 use this option to specify where to find it.
688 * When natively debugging programs on PowerPC BookE processors running
689 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
690 watchpoints, which specify a mask in addition to an address to watch.
691 The mask specifies that some bits of an address (the bits which are
692 reset in the mask) should be ignored when matching the address accessed
693 by the inferior against the watchpoint address. See the "PowerPC Embedded"
694 section in the user manual for more details.
696 * The new option --once causes GDBserver to stop listening for connections once
697 the first connection is made. The listening port used by GDBserver will
698 become available after that.
700 * New commands "info macros" and "alias" have been added.
702 * New function parameters suffix @entry specifies value of function parameter
703 at the time the function got called. Entry values are available only since
709 "!" is now an alias of the "shell" command.
710 Note that no space is needed between "!" and SHELL COMMAND.
714 watch EXPRESSION mask MASK_VALUE
715 The watch command now supports the mask argument which allows creation
716 of masked watchpoints, if the current architecture supports this feature.
718 info auto-load-scripts [REGEXP]
719 This command was formerly named "maintenance print section-scripts".
720 It is now generally useful and is no longer a maintenance-only command.
722 info macro [-all] [--] MACRO
723 The info macro command has new options `-all' and `--'. The first for
724 printing all definitions of a macro. The second for explicitly specifying
725 the end of arguments and the beginning of the macro name in case the macro
726 name starts with a hyphen.
728 collect[/s] EXPRESSIONS
729 The tracepoint collect command now takes an optional modifier "/s"
730 that directs it to dereference pointer-to-character types and
731 collect the bytes of memory up to a zero byte. The behavior is
732 similar to what you see when you use the regular print command on a
733 string. An optional integer following the "/s" sets a bound on the
734 number of bytes that will be collected.
737 The trace start command now interprets any supplied arguments as a
738 note to be recorded with the trace run, with an effect similar to
739 setting the variable trace-notes.
742 The trace stop command now interprets any arguments as a note to be
743 mentioned along with the tstatus report that the trace was stopped
744 with a command. The effect is similar to setting the variable
747 * Tracepoints can now be enabled and disabled at any time after a trace
748 experiment has been started using the standard "enable" and "disable"
749 commands. It is now possible to start a trace experiment with no enabled
750 tracepoints; GDB will display a warning, but will allow the experiment to
751 begin, assuming that tracepoints will be enabled as needed while the trace
754 * Fast tracepoints on 32-bit x86-architectures can now be placed at
755 locations with 4-byte instructions, when they were previously
756 limited to locations with instructions of 5 bytes or longer.
760 set debug dwarf2-read
761 show debug dwarf2-read
762 Turns on or off display of debugging messages related to reading
763 DWARF debug info. The default is off.
765 set debug symtab-create
766 show debug symtab-create
767 Turns on or off display of debugging messages related to symbol table
768 creation. The default is off.
772 Set the GDB prompt, and allow escape sequences to be inserted to
773 display miscellaneous information (see 'help set extended-prompt'
774 for the list of sequences). This prompt (and any information
775 accessed through the escape sequences) is updated every time the
778 set print entry-values (both|compact|default|if-needed|no|only|preferred)
779 show print entry-values
780 Set printing of frame argument values at function entry. In some cases
781 GDB can determine the value of function argument which was passed by the
782 function caller, even if the value was modified inside the called function.
784 set debug entry-values
785 show debug entry-values
786 Control display of debugging info for determining frame argument values at
787 function entry and virtual tail call frames.
789 set basenames-may-differ
790 show basenames-may-differ
791 Set whether a source file may have multiple base names.
792 (A "base name" is the name of a file with the directory part removed.
793 Example: The base name of "/home/user/hello.c" is "hello.c".)
794 If set, GDB will canonicalize file names (e.g., expand symlinks)
795 before comparing them. Canonicalization is an expensive operation,
796 but it allows the same file be known by more than one base name.
797 If not set (the default), all source files are assumed to have just
798 one base name, and gdb will do file name comparisons more efficiently.
804 Set a user name and notes for the current and any future trace runs.
805 This is useful for long-running and/or disconnected traces, to
806 inform others (or yourself) as to who is running the trace, supply
807 contact information, or otherwise explain what is going on.
810 show trace-stop-notes
811 Set a note attached to the trace run, that is displayed when the
812 trace has been stopped by a tstop command. This is useful for
813 instance as an explanation, if you are stopping a trace run that was
814 started by someone else.
820 Dynamically enable a tracepoint in a started trace experiment.
824 Dynamically disable a tracepoint in a started trace experiment.
828 Set the user and notes of the trace run.
832 Query the current status of a tracepoint.
836 Query the minimum length of instruction at which a fast tracepoint may
839 * Dcache size (number of lines) and line-size are now runtime-configurable
840 via "set dcache line" and "set dcache line-size" commands.
844 Texas Instruments TMS320C6x tic6x-*-*
848 Renesas RL78 rl78-*-elf
850 *** Changes in GDB 7.3.1
852 * The build failure for NetBSD and OpenBSD targets have now been fixed.
854 *** Changes in GDB 7.3
856 * GDB has a new command: "thread find [REGEXP]".
857 It finds the thread id whose name, target id, or thread extra info
858 matches the given regular expression.
860 * The "catch syscall" command now works on mips*-linux* targets.
862 * The -data-disassemble MI command now supports modes 2 and 3 for
863 dumping the instruction opcodes.
865 * New command line options
867 -data-directory DIR Specify DIR as the "data-directory".
868 This is mostly for testing purposes.
870 * The "maint set python auto-load on|off" command has been renamed to
871 "set auto-load-scripts on|off".
873 * GDB has a new command: "set directories".
874 It is like the "dir" command except that it replaces the
875 source path list instead of augmenting it.
877 * GDB now understands thread names.
879 On GNU/Linux, "info threads" will display the thread name as set by
880 prctl or pthread_setname_np.
882 There is also a new command, "thread name", which can be used to
883 assign a name internally for GDB to display.
886 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
887 has been integrated into GDB.
891 ** The function gdb.Write now accepts an optional keyword 'stream'.
892 This keyword, when provided, will direct the output to either
893 stdout, stderr, or GDB's logging output.
895 ** Parameters can now be be sub-classed in Python, and in particular
896 you may implement the get_set_doc and get_show_doc functions.
897 This improves how Parameter set/show documentation is processed
898 and allows for more dynamic content.
900 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
901 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
902 have an is_valid method.
904 ** Breakpoints can now be sub-classed in Python, and in particular
905 you may implement a 'stop' function that is executed each time
906 the inferior reaches that breakpoint.
908 ** New function gdb.lookup_global_symbol looks up a global symbol.
910 ** GDB values in Python are now callable if the value represents a
911 function. For example, if 'some_value' represents a function that
912 takes two integer parameters and returns a value, you can call
913 that function like so:
915 result = some_value (10,20)
917 ** Module gdb.types has been added.
918 It contains a collection of utilities for working with gdb.Types objects:
919 get_basic_type, has_field, make_enum_dict.
921 ** Module gdb.printing has been added.
922 It contains utilities for writing and registering pretty-printers.
923 New classes: PrettyPrinter, SubPrettyPrinter,
924 RegexpCollectionPrettyPrinter.
925 New function: register_pretty_printer.
927 ** New commands "info pretty-printers", "enable pretty-printer" and
928 "disable pretty-printer" have been added.
930 ** gdb.parameter("directories") is now available.
932 ** New function gdb.newest_frame returns the newest frame in the
935 ** The gdb.InferiorThread class has a new "name" attribute. This
936 holds the thread's name.
938 ** Python Support for Inferior events.
939 Python scripts can add observers to be notified of events
940 occurring in the process being debugged.
941 The following events are currently supported:
942 - gdb.events.cont Continue event.
943 - gdb.events.exited Inferior exited event.
944 - gdb.events.stop Signal received, and Breakpoint hit events.
948 ** GDB now puts template parameters in scope when debugging in an
949 instantiation. For example, if you have:
951 template<int X> int func (void) { return X; }
953 then if you step into func<5>, "print X" will show "5". This
954 feature requires proper debuginfo support from the compiler; it
955 was added to GCC 4.5.
957 ** The motion commands "next", "finish", "until", and "advance" now
958 work better when exceptions are thrown. In particular, GDB will
959 no longer lose control of the inferior; instead, the GDB will
960 stop the inferior at the point at which the exception is caught.
961 This functionality requires a change in the exception handling
962 code that was introduced in GCC 4.5.
964 * GDB now follows GCC's rules on accessing volatile objects when
965 reading or writing target state during expression evaluation.
966 One notable difference to prior behavior is that "print x = 0"
967 no longer generates a read of x; the value of the assignment is
968 now always taken directly from the value being assigned.
970 * GDB now has some support for using labels in the program's source in
971 linespecs. For instance, you can use "advance label" to continue
972 execution to a label.
974 * GDB now has support for reading and writing a new .gdb_index
975 section. This section holds a fast index of DWARF debugging
976 information and can be used to greatly speed up GDB startup and
977 operation. See the documentation for `save gdb-index' for details.
979 * The "watch" command now accepts an optional "-location" argument.
980 When used, this causes GDB to watch the memory referred to by the
981 expression. Such a watchpoint is never deleted due to it going out
984 * GDB now supports thread debugging of core dumps on GNU/Linux.
986 GDB now activates thread debugging using the libthread_db library
987 when debugging GNU/Linux core dumps, similarly to when debugging
988 live processes. As a result, when debugging a core dump file, GDB
989 is now able to display pthread_t ids of threads. For example, "info
990 threads" shows the same output as when debugging the process when it
991 was live. In earlier releases, you'd see something like this:
994 * 1 LWP 6780 main () at main.c:10
996 While now you see this:
999 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1001 It is also now possible to inspect TLS variables when debugging core
1004 When debugging a core dump generated on a machine other than the one
1005 used to run GDB, you may need to point GDB at the correct
1006 libthread_db library with the "set libthread-db-search-path"
1007 command. See the user manual for more details on this command.
1009 * When natively debugging programs on PowerPC BookE processors running
1010 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1011 which stop execution of the inferior whenever it executes an instruction
1012 at any address within the specified range. See the "PowerPC Embedded"
1013 section in the user manual for more details.
1015 * New features in the GDB remote stub, GDBserver
1017 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1018 and i686 LynxOS (version 5.x).
1020 ** GDBserver is now supported on Blackfin Linux.
1022 * New native configurations
1024 ia64 HP-UX ia64-*-hpux*
1028 Analog Devices, Inc. Blackfin Processor bfin-*
1030 * Ada task switching is now supported on sparc-elf targets when
1031 debugging a program using the Ravenscar Profile. For more information,
1032 see the "Tasking Support when using the Ravenscar Profile" section
1033 in the GDB user manual.
1035 * Guile support was removed.
1037 * New features in the GNU simulator
1039 ** The --map-info flag lists all known core mappings.
1041 ** CFI flashes may be simulated via the "cfi" device.
1043 *** Changes in GDB 7.2
1045 * Shared library support for remote targets by default
1047 When GDB is configured for a generic, non-OS specific target, like
1048 for example, --target=arm-eabi or one of the many *-*-elf targets,
1049 GDB now queries remote stubs for loaded shared libraries using the
1050 `qXfer:libraries:read' packet. Previously, shared library support
1051 was always disabled for such configurations.
1055 ** Argument Dependent Lookup (ADL)
1057 In C++ ADL lookup directs function search to the namespaces of its
1058 arguments even if the namespace has not been imported.
1068 Here the compiler will search for `foo' in the namespace of 'b'
1069 and find A::foo. GDB now supports this. This construct is commonly
1070 used in the Standard Template Library for operators.
1072 ** Improved User Defined Operator Support
1074 In addition to member operators, GDB now supports lookup of operators
1075 defined in a namespace and imported with a `using' directive, operators
1076 defined in the global scope, operators imported implicitly from an
1077 anonymous namespace, and the ADL operators mentioned in the previous
1079 GDB now also supports proper overload resolution for all the previously
1080 mentioned flavors of operators.
1082 ** static const class members
1084 Printing of static const class members that are initialized in the
1085 class definition has been fixed.
1087 * Windows Thread Information Block access.
1089 On Windows targets, GDB now supports displaying the Windows Thread
1090 Information Block (TIB) structure. This structure is visible either
1091 by using the new command `info w32 thread-information-block' or, by
1092 dereferencing the new convenience variable named `$_tlb', a
1093 thread-specific pointer to the TIB. This feature is also supported
1094 when remote debugging using GDBserver.
1096 * Static tracepoints
1098 Static tracepoints are calls in the user program into a tracing
1099 library. One such library is a port of the LTTng kernel tracer to
1100 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1101 When debugging with GDBserver, GDB now supports combining the GDB
1102 tracepoint machinery with such libraries. For example: the user can
1103 use GDB to probe a static tracepoint marker (a call from the user
1104 program into the tracing library) with the new "strace" command (see
1105 "New commands" below). This creates a "static tracepoint" in the
1106 breakpoint list, that can be manipulated with the same feature set
1107 as fast and regular tracepoints. E.g., collect registers, local and
1108 global variables, collect trace state variables, and define
1109 tracepoint conditions. In addition, the user can collect extra
1110 static tracepoint marker specific data, by collecting the new
1111 $_sdata internal variable. When analyzing the trace buffer, you can
1112 inspect $_sdata like any other variable available to GDB. For more
1113 information, see the "Tracepoints" chapter in GDB user manual. New
1114 remote packets have been defined to support static tracepoints, see
1115 the "New remote packets" section below.
1117 * Better reconstruction of tracepoints after disconnected tracing
1119 GDB will attempt to download the original source form of tracepoint
1120 definitions when starting a trace run, and then will upload these
1121 upon reconnection to the target, resulting in a more accurate
1122 reconstruction of the tracepoints that are in use on the target.
1126 You can now exercise direct control over the ways that GDB can
1127 affect your program. For instance, you can disallow the setting of
1128 breakpoints, so that the program can run continuously (assuming
1129 non-stop mode). In addition, the "observer" variable is available
1130 to switch all of the different controls; in observer mode, GDB
1131 cannot affect the target's behavior at all, which is useful for
1132 tasks like diagnosing live systems in the field.
1134 * The new convenience variable $_thread holds the number of the
1137 * New remote packets
1141 Return the address of the Windows Thread Information Block of a given thread.
1145 In response to several of the tracepoint packets, the target may now
1146 also respond with a number of intermediate `qRelocInsn' request
1147 packets before the final result packet, to have GDB handle
1148 relocating an instruction to execute at a different address. This
1149 is particularly useful for stubs that support fast tracepoints. GDB
1150 reports support for this feature in the qSupported packet.
1154 List static tracepoint markers in the target program.
1158 List static tracepoint markers at a given address in the target
1161 qXfer:statictrace:read
1163 Read the static trace data collected (by a `collect $_sdata'
1164 tracepoint action). The remote stub reports support for this packet
1165 to gdb's qSupported query.
1169 Send the current settings of GDB's permission flags.
1173 Send part of the source (textual) form of a tracepoint definition,
1174 which includes location, conditional, and action list.
1176 * The source command now accepts a -s option to force searching for the
1177 script in the source search path even if the script name specifies
1180 * New features in the GDB remote stub, GDBserver
1182 - GDBserver now support tracepoints (including fast tracepoints, and
1183 static tracepoints). The feature is currently supported by the
1184 i386-linux and amd64-linux builds. See the "Tracepoints support
1185 in gdbserver" section in the manual for more information.
1187 GDBserver JIT compiles the tracepoint's conditional agent
1188 expression bytecode into native code whenever possible for low
1189 overhead dynamic tracepoints conditionals. For such tracepoints,
1190 an expression that examines program state is evaluated when the
1191 tracepoint is reached, in order to determine whether to capture
1192 trace data. If the condition is simple and false, processing the
1193 tracepoint finishes very quickly and no data is gathered.
1195 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1196 for static tracepoints support.
1198 - GDBserver now supports x86_64 Windows 64-bit debugging.
1200 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1201 it understands register description.
1203 * The --batch flag now disables pagination and queries.
1205 * X86 general purpose registers
1207 GDB now supports reading/writing byte, word and double-word x86
1208 general purpose registers directly. This means you can use, say,
1209 $ah or $ax to refer, respectively, to the byte register AH and
1210 16-bit word register AX that are actually portions of the 32-bit
1211 register EAX or 64-bit register RAX.
1213 * The `commands' command now accepts a range of breakpoints to modify.
1214 A plain `commands' following a command that creates multiple
1215 breakpoints affects all the breakpoints set by that command. This
1216 applies to breakpoints set by `rbreak', and also applies when a
1217 single `break' command creates multiple breakpoints (e.g.,
1218 breakpoints on overloaded c++ functions).
1220 * The `rbreak' command now accepts a filename specification as part of
1221 its argument, limiting the functions selected by the regex to those
1222 in the specified file.
1224 * Support for remote debugging Windows and SymbianOS shared libraries
1225 from Unix hosts has been improved. Non Windows GDB builds now can
1226 understand target reported file names that follow MS-DOS based file
1227 system semantics, such as file names that include drive letters and
1228 use the backslash character as directory separator. This makes it
1229 possible to transparently use the "set sysroot" and "set
1230 solib-search-path" on Unix hosts to point as host copies of the
1231 target's shared libraries. See the new command "set
1232 target-file-system-kind" described below, and the "Commands to
1233 specify files" section in the user manual for more information.
1237 eval template, expressions...
1238 Convert the values of one or more expressions under the control
1239 of the string template to a command line, and call it.
1241 set target-file-system-kind unix|dos-based|auto
1242 show target-file-system-kind
1243 Set or show the assumed file system kind for target reported file
1246 save breakpoints <filename>
1247 Save all current breakpoint definitions to a file suitable for use
1248 in a later debugging session. To read the saved breakpoint
1249 definitions, use the `source' command.
1251 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1254 info static-tracepoint-markers
1255 Display information about static tracepoint markers in the target.
1257 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1258 Define a static tracepoint by probing a marker at the given
1259 function, line, address, or marker ID.
1263 Enable and disable observer mode.
1265 set may-write-registers on|off
1266 set may-write-memory on|off
1267 set may-insert-breakpoints on|off
1268 set may-insert-tracepoints on|off
1269 set may-insert-fast-tracepoints on|off
1270 set may-interrupt on|off
1271 Set individual permissions for GDB effects on the target. Note that
1272 some of these settings can have undesirable or surprising
1273 consequences, particularly when changed in the middle of a session.
1274 For instance, disabling the writing of memory can prevent
1275 breakpoints from being inserted, cause single-stepping to fail, or
1276 even crash your program, if you disable after breakpoints have been
1277 inserted. However, GDB should not crash.
1279 set record memory-query on|off
1280 show record memory-query
1281 Control whether to stop the inferior if memory changes caused
1282 by an instruction cannot be recorded.
1287 The disassemble command now supports "start,+length" form of two arguments.
1291 ** GDB now provides a new directory location, called the python directory,
1292 where Python scripts written for GDB can be installed. The location
1293 of that directory is <data-directory>/python, where <data-directory>
1294 is the GDB data directory. For more details, see section `Scripting
1295 GDB using Python' in the manual.
1297 ** The GDB Python API now has access to breakpoints, symbols, symbol
1298 tables, program spaces, inferiors, threads and frame's code blocks.
1299 Additionally, GDB Parameters can now be created from the API, and
1300 manipulated via set/show in the CLI.
1302 ** New functions gdb.target_charset, gdb.target_wide_charset,
1303 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1305 ** New exception gdb.GdbError.
1307 ** Pretty-printers are now also looked up in the current program space.
1309 ** Pretty-printers can now be individually enabled and disabled.
1311 ** GDB now looks for names of Python scripts to auto-load in a
1312 special section named `.debug_gdb_scripts', in addition to looking
1313 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1315 * Tracepoint actions were unified with breakpoint commands. In particular,
1316 there are no longer differences in "info break" output for breakpoints and
1317 tracepoints and the "commands" command can be used for both tracepoints and
1318 regular breakpoints.
1322 ARM Symbian arm*-*-symbianelf*
1324 * D language support.
1325 GDB now supports debugging programs written in the D programming
1328 * GDB now supports the extended ptrace interface for PowerPC which is
1329 available since Linux kernel version 2.6.34. This automatically enables
1330 any hardware breakpoints and additional hardware watchpoints available in
1331 the processor. The old ptrace interface exposes just one hardware
1332 watchpoint and no hardware breakpoints.
1334 * GDB is now able to use the Data Value Compare (DVC) register available on
1335 embedded PowerPC processors to implement in hardware simple watchpoint
1336 conditions of the form:
1338 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1340 This works in native GDB running on Linux kernels with the extended ptrace
1341 interface mentioned above.
1343 *** Changes in GDB 7.1
1347 ** Namespace Support
1349 GDB now supports importing of namespaces in C++. This enables the
1350 user to inspect variables from imported namespaces. Support for
1351 namepace aliasing has also been added. So, if a namespace is
1352 aliased in the current scope (e.g. namepace C=A; ) the user can
1353 print variables using the alias (e.g. (gdb) print C::x).
1357 All known bugs relating to the printing of virtual base class were
1358 fixed. It is now possible to call overloaded static methods using a
1363 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1364 and reinterpret_cast<> are now handled by the C++ expression parser.
1368 Xilinx MicroBlaze microblaze-*-*
1373 Xilinx MicroBlaze microblaze
1376 * Multi-program debugging.
1378 GDB now has support for multi-program (a.k.a. multi-executable or
1379 multi-exec) debugging. This allows for debugging multiple inferiors
1380 simultaneously each running a different program under the same GDB
1381 session. See "Debugging Multiple Inferiors and Programs" in the
1382 manual for more information. This implied some user visible changes
1383 in the multi-inferior support. For example, "info inferiors" now
1384 lists inferiors that are not running yet or that have exited
1385 already. See also "New commands" and "New options" below.
1387 * New tracing features
1389 GDB's tracepoint facility now includes several new features:
1391 ** Trace state variables
1393 GDB tracepoints now include support for trace state variables, which
1394 are variables managed by the target agent during a tracing
1395 experiment. They are useful for tracepoints that trigger each
1396 other, so for instance one tracepoint can count hits in a variable,
1397 and then a second tracepoint has a condition that is true when the
1398 count reaches a particular value. Trace state variables share the
1399 $-syntax of GDB convenience variables, and can appear in both
1400 tracepoint actions and condition expressions. Use the "tvariable"
1401 command to create, and "info tvariables" to view; see "Trace State
1402 Variables" in the manual for more detail.
1406 GDB now includes an option for defining fast tracepoints, which
1407 targets may implement more efficiently, such as by installing a jump
1408 into the target agent rather than a trap instruction. The resulting
1409 speedup can be by two orders of magnitude or more, although the
1410 tradeoff is that some program locations on some target architectures
1411 might not allow fast tracepoint installation, for instance if the
1412 instruction to be replaced is shorter than the jump. To request a
1413 fast tracepoint, use the "ftrace" command, with syntax identical to
1414 the regular trace command.
1416 ** Disconnected tracing
1418 It is now possible to detach GDB from the target while it is running
1419 a trace experiment, then reconnect later to see how the experiment
1420 is going. In addition, a new variable disconnected-tracing lets you
1421 tell the target agent whether to continue running a trace if the
1422 connection is lost unexpectedly.
1426 GDB now has the ability to save the trace buffer into a file, and
1427 then use that file as a target, similarly to you can do with
1428 corefiles. You can select trace frames, print data that was
1429 collected in them, and use tstatus to display the state of the
1430 tracing run at the moment that it was saved. To create a trace
1431 file, use "tsave <filename>", and to use it, do "target tfile
1434 ** Circular trace buffer
1436 You can ask the target agent to handle the trace buffer as a
1437 circular buffer, discarding the oldest trace frames to make room for
1438 newer ones, by setting circular-trace-buffer to on. This feature may
1439 not be available for all target agents.
1444 The disassemble command, when invoked with two arguments, now requires
1445 the arguments to be comma-separated.
1448 The info variables command now displays variable definitions. Files
1449 which only declare a variable are not shown.
1452 The source command is now capable of sourcing Python scripts.
1453 This feature is dependent on the debugger being build with Python
1456 Related to this enhancement is also the introduction of a new command
1457 "set script-extension" (see below).
1459 * New commands (for set/show, see "New options" below)
1461 record save [<FILENAME>]
1462 Save a file (in core file format) containing the process record
1463 execution log for replay debugging at a later time.
1465 record restore <FILENAME>
1466 Restore the process record execution log that was saved at an
1467 earlier time, for replay debugging.
1469 add-inferior [-copies <N>] [-exec <FILENAME>]
1472 clone-inferior [-copies <N>] [ID]
1473 Make a new inferior ready to execute the same program another
1474 inferior has loaded.
1479 maint info program-spaces
1480 List the program spaces loaded into GDB.
1482 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1483 show remote interrupt-sequence
1484 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1485 as the sequence to the remote target in order to interrupt the execution.
1486 Ctrl-C is a default. Some system prefers BREAK which is high level of
1487 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1488 Magic SysRq g. It is BREAK signal and character 'g'.
1490 set remote interrupt-on-connect [on | off]
1491 show remote interrupt-on-connect
1492 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1493 remote target when gdb connects to it. This is needed when you debug
1496 set remotebreak [on | off]
1498 Deprecated. Use "set/show remote interrupt-sequence" instead.
1500 tvariable $NAME [ = EXP ]
1501 Create or modify a trace state variable.
1504 List trace state variables and their values.
1506 delete tvariable $NAME ...
1507 Delete one or more trace state variables.
1510 Evaluate the given expressions without collecting anything into the
1511 trace buffer. (Valid in tracepoint actions only.)
1513 ftrace FN / FILE:LINE / *ADDR
1514 Define a fast tracepoint at the given function, line, or address.
1516 * New expression syntax
1518 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1519 GDB now parses 0b101010 identically with 42.
1523 set follow-exec-mode new|same
1524 show follow-exec-mode
1525 Control whether GDB reuses the same inferior across an exec call or
1526 creates a new one. This is useful to be able to restart the old
1527 executable after the inferior having done an exec call.
1529 set default-collect EXPR, ...
1530 show default-collect
1531 Define a list of expressions to be collected at each tracepoint.
1532 This is a useful way to ensure essential items are not overlooked,
1533 such as registers or a critical global variable.
1535 set disconnected-tracing
1536 show disconnected-tracing
1537 If set to 1, the target is instructed to continue tracing if it
1538 loses its connection to GDB. If 0, the target is to stop tracing
1541 set circular-trace-buffer
1542 show circular-trace-buffer
1543 If set to on, the target is instructed to use a circular trace buffer
1544 and discard the oldest trace frames instead of stopping the trace due
1545 to a full trace buffer. If set to off, the trace stops when the buffer
1546 fills up. Some targets may not support this.
1548 set script-extension off|soft|strict
1549 show script-extension
1550 If set to "off", the debugger does not perform any script language
1551 recognition, and all sourced files are assumed to be GDB scripts.
1552 If set to "soft" (the default), files are sourced according to
1553 filename extension, falling back to GDB scripts if the first
1555 If set to "strict", files are sourced according to filename extension.
1557 set ada trust-PAD-over-XVS on|off
1558 show ada trust-PAD-over-XVS
1559 If off, activate a workaround against a bug in the debugging information
1560 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1561 the GCC sources for more information about the GNAT encoding and
1562 PAD types in particular). It is always safe to set this option to
1563 off, but this introduces a slight performance penalty. The default
1566 * Python API Improvements
1568 ** GDB provides the new class gdb.LazyString. This is useful in
1569 some pretty-printing cases. The new method gdb.Value.lazy_string
1570 provides a simple way to create objects of this type.
1572 ** The fields returned by gdb.Type.fields now have an
1573 `is_base_class' attribute.
1575 ** The new method gdb.Type.range returns the range of an array type.
1577 ** The new method gdb.parse_and_eval can be used to parse and
1578 evaluate an expression.
1580 * New remote packets
1583 Define a trace state variable.
1586 Get the current value of a trace state variable.
1589 Set desired tracing behavior upon disconnection.
1592 Set the trace buffer to be linear or circular.
1595 Get data about the tracepoints currently in use.
1599 Process record now works correctly with hardware watchpoints.
1601 Multiple bug fixes have been made to the mips-irix port, making it
1602 much more reliable. In particular:
1603 - Debugging threaded applications is now possible again. Previously,
1604 GDB would hang while starting the program, or while waiting for
1605 the program to stop at a breakpoint.
1606 - Attaching to a running process no longer hangs.
1607 - An error occurring while loading a core file has been fixed.
1608 - Changing the value of the PC register now works again. This fixes
1609 problems observed when using the "jump" command, or when calling
1610 a function from GDB, or even when assigning a new value to $pc.
1611 - With the "finish" and "return" commands, the return value for functions
1612 returning a small array is now correctly printed.
1613 - It is now possible to break on shared library code which gets executed
1614 during a shared library init phase (code executed while executing
1615 their .init section). Previously, the breakpoint would have no effect.
1616 - GDB is now able to backtrace through the signal handler for
1617 non-threaded programs.
1619 PIE (Position Independent Executable) programs debugging is now supported.
1620 This includes debugging execution of PIC (Position Independent Code) shared
1621 libraries although for that, it should be possible to run such libraries as an
1624 *** Changes in GDB 7.0
1626 * GDB now has an interface for JIT compilation. Applications that
1627 dynamically generate code can create symbol files in memory and register
1628 them with GDB. For users, the feature should work transparently, and
1629 for JIT developers, the interface is documented in the GDB manual in the
1630 "JIT Compilation Interface" chapter.
1632 * Tracepoints may now be conditional. The syntax is as for
1633 breakpoints; either an "if" clause appended to the "trace" command,
1634 or the "condition" command is available. GDB sends the condition to
1635 the target for evaluation using the same bytecode format as is used
1636 for tracepoint actions.
1638 * The disassemble command now supports: an optional /r modifier, print the
1639 raw instructions in hex as well as in symbolic form, and an optional /m
1640 modifier to print mixed source+assembly.
1642 * Process record and replay
1644 In a architecture environment that supports ``process record and
1645 replay'', ``process record and replay'' target can record a log of
1646 the process execution, and replay it with both forward and reverse
1649 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1650 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1651 set execution-direction {forward|reverse}, for targets that support
1654 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1655 feature is available with a native GDB running on kernel version
1658 * GDB now has support for multi-byte and wide character sets on the
1659 target. Strings whose character type is wchar_t, char16_t, or
1660 char32_t are now correctly printed. GDB supports wide- and unicode-
1661 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1662 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1663 `printf'. This feature requires iconv to work properly; if your
1664 system does not have a working iconv, GDB can use GNU libiconv. See
1665 the installation instructions for more information.
1667 * GDB now supports automatic retrieval of shared library files from
1668 remote targets. To use this feature, specify a system root that begins
1669 with the `remote:' prefix, either via the `set sysroot' command or via
1670 the `--with-sysroot' configure-time option.
1672 * "info sharedlibrary" now takes an optional regex of libraries to show,
1673 and it now reports if a shared library has no debugging information.
1675 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1676 now complete on file names.
1678 * When completing in expressions, gdb will attempt to limit
1679 completions to allowable structure or union fields, where appropriate.
1680 For instance, consider:
1682 # struct example { int f1; double f2; };
1683 # struct example variable;
1686 If the user types TAB at the end of this command line, the available
1687 completions will be "f1" and "f2".
1689 * Inlined functions are now supported. They show up in backtraces, and
1690 the "step", "next", and "finish" commands handle them automatically.
1692 * GDB now supports the token-splicing (##) and stringification (#)
1693 operators when expanding macros. It also supports variable-arity
1696 * GDB now supports inspecting extra signal information, exported by
1697 the new $_siginfo convenience variable. The feature is currently
1698 implemented on linux ARM, i386 and amd64.
1700 * GDB can now display the VFP floating point registers and NEON vector
1701 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1702 can provide these registers (requires Linux 2.6.30 or later). Remote
1703 and simulator targets may also provide them.
1705 * New remote packets
1708 Search memory for a sequence of bytes.
1711 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1712 operation over reliable transport links. Use of this packet is
1713 controlled by the `set remote noack-packet' command.
1716 Kill the process with the specified process ID. Use this in preference
1717 to `k' when multiprocess protocol extensions are supported.
1720 Obtains additional operating system information
1724 Read or write additional signal information.
1726 * Removed remote protocol undocumented extension
1728 An undocumented extension to the remote protocol's `S' stop reply
1729 packet that permited the stub to pass a process id was removed.
1730 Remote servers should use the `T' stop reply packet instead.
1732 * GDB now supports multiple function calling conventions according to the
1733 DWARF-2 DW_AT_calling_convention function attribute.
1735 * The SH target utilizes the aforementioned change to distinguish between gcc
1736 and Renesas calling convention. It also adds the new CLI commands
1737 `set/show sh calling-convention'.
1739 * GDB can now read compressed debug sections, as produced by GNU gold
1740 with the --compress-debug-sections=zlib flag.
1742 * 64-bit core files are now supported on AIX.
1744 * Thread switching is now supported on Tru64.
1746 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1747 which will be allocated using malloc later in program execution.
1749 * The qXfer:libraries:read remote procotol packet now allows passing a
1750 list of section offsets.
1752 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1753 conditions handling signals delivered during attach or thread creation
1754 have also been fixed.
1756 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1757 From the user's standpoint, all unqualified instances of True and False
1758 are treated as the standard definitions, regardless of context.
1760 * GDB now parses C++ symbol and type names more flexibly. For
1763 template<typename T> class C { };
1766 GDB will now correctly handle all of:
1768 ptype C<char const *>
1769 ptype C<char const*>
1770 ptype C<const char *>
1771 ptype C<const char*>
1773 * New features in the GDB remote stub, gdbserver
1775 - The "--wrapper" command-line argument tells gdbserver to use a
1776 wrapper program to launch programs for debugging.
1778 - On PowerPC and S/390 targets, it is now possible to use a single
1779 gdbserver executable to debug both 32-bit and 64-bit programs.
1780 (This requires gdbserver itself to be built as a 64-bit executable.)
1782 - gdbserver uses the new noack protocol mode for TCP connections to
1783 reduce communications latency, if also supported and enabled in GDB.
1785 - Support for the sparc64-linux-gnu target is now included in
1788 - The amd64-linux build of gdbserver now supports debugging both
1789 32-bit and 64-bit programs.
1791 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1792 now support hardware watchpoints, and will use them automatically
1797 GDB now has support for scripting using Python. Whether this is
1798 available is determined at configure time.
1800 New GDB commands can now be written in Python.
1802 * Ada tasking support
1804 Ada tasks can now be inspected in GDB. The following commands have
1808 Print the list of Ada tasks.
1810 Print detailed information about task number N.
1812 Print the task number of the current task.
1814 Switch the context of debugging to task number N.
1816 * Support for user-defined prefixed commands. The "define" command can
1817 add new commands to existing prefixes, e.g. "target".
1819 * Multi-inferior, multi-process debugging.
1821 GDB now has generalized support for multi-inferior debugging. See
1822 "Debugging Multiple Inferiors" in the manual for more information.
1823 Although availability still depends on target support, the command
1824 set is more uniform now. The GNU/Linux specific multi-forks support
1825 has been migrated to this new framework. This implied some user
1826 visible changes; see "New commands" and also "Removed commands"
1829 * Target descriptions can now describe the target OS ABI. See the
1830 "Target Description Format" section in the user manual for more
1833 * Target descriptions can now describe "compatible" architectures
1834 to indicate that the target can execute applications for a different
1835 architecture in addition to those for the main target architecture.
1836 See the "Target Description Format" section in the user manual for
1839 * Multi-architecture debugging.
1841 GDB now includes general supports for debugging applications on
1842 hybrid systems that use more than one single processor architecture
1843 at the same time. Each such hybrid architecture still requires
1844 specific support to be added. The only hybrid architecture supported
1845 in this version of GDB is the Cell Broadband Engine.
1847 * GDB now supports integrated debugging of Cell/B.E. applications that
1848 use both the PPU and SPU architectures. To enable support for hybrid
1849 Cell/B.E. debugging, you need to configure GDB to support both the
1850 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1851 --enable-targets configure option.
1853 * Non-stop mode debugging.
1855 For some targets, GDB now supports an optional mode of operation in
1856 which you can examine stopped threads while other threads continue
1857 to execute freely. This is referred to as non-stop mode, with the
1858 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1859 section in the user manual for more information.
1861 To be able to support remote non-stop debugging, a remote stub needs
1862 to implement the non-stop mode remote protocol extensions, as
1863 described in the "Remote Non-Stop" section of the user manual. The
1864 GDB remote stub, gdbserver, has been adjusted to support these
1865 extensions on linux targets.
1867 * New commands (for set/show, see "New options" below)
1869 catch syscall [NAME(S) | NUMBER(S)]
1870 Catch system calls. Arguments, which should be names of system
1871 calls or their numbers, mean catch only those syscalls. Without
1872 arguments, every syscall will be caught. When the inferior issues
1873 any of the specified syscalls, GDB will stop and announce the system
1874 call, both when it is called and when its call returns. This
1875 feature is currently available with a native GDB running on the
1876 Linux Kernel, under the following architectures: x86, x86_64,
1877 PowerPC and PowerPC64.
1879 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1881 Search memory for a sequence of bytes.
1883 maint set python print-stack
1884 maint show python print-stack
1885 Show a stack trace when an error is encountered in a Python script.
1888 Invoke CODE by passing it to the Python interpreter.
1893 These allow macros to be defined, undefined, and listed
1897 Show operating system information about processes.
1900 List the inferiors currently under GDB's control.
1903 Switch focus to inferior number NUM.
1906 Detach from inferior number NUM.
1909 Kill inferior number NUM.
1913 set spu stop-on-load
1914 show spu stop-on-load
1915 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1917 set spu auto-flush-cache
1918 show spu auto-flush-cache
1919 Control whether to automatically flush the software-managed cache
1920 during Cell/B.E. debugging.
1922 set sh calling-convention
1923 show sh calling-convention
1924 Control the calling convention used when calling SH target functions.
1927 show debug timestamp
1928 Control display of timestamps with GDB debugging output.
1930 set disassemble-next-line
1931 show disassemble-next-line
1932 Control display of disassembled source lines or instructions when
1935 set remote noack-packet
1936 show remote noack-packet
1937 Set/show the use of remote protocol QStartNoAckMode packet. See above
1938 under "New remote packets."
1940 set remote query-attached-packet
1941 show remote query-attached-packet
1942 Control use of remote protocol `qAttached' (query-attached) packet.
1944 set remote read-siginfo-object
1945 show remote read-siginfo-object
1946 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1949 set remote write-siginfo-object
1950 show remote write-siginfo-object
1951 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1954 set remote reverse-continue
1955 show remote reverse-continue
1956 Control use of remote protocol 'bc' (reverse-continue) packet.
1958 set remote reverse-step
1959 show remote reverse-step
1960 Control use of remote protocol 'bs' (reverse-step) packet.
1962 set displaced-stepping
1963 show displaced-stepping
1964 Control displaced stepping mode. Displaced stepping is a way to
1965 single-step over breakpoints without removing them from the debuggee.
1966 Also known as "out-of-line single-stepping".
1969 show debug displaced
1970 Control display of debugging info for displaced stepping.
1972 maint set internal-error
1973 maint show internal-error
1974 Control what GDB does when an internal error is detected.
1976 maint set internal-warning
1977 maint show internal-warning
1978 Control what GDB does when an internal warning is detected.
1983 Use a wrapper program to launch programs for debugging.
1985 set multiple-symbols (all|ask|cancel)
1986 show multiple-symbols
1987 The value of this variable can be changed to adjust the debugger behavior
1988 when an expression or a breakpoint location contains an ambiguous symbol
1989 name (an overloaded function name, for instance).
1991 set breakpoint always-inserted
1992 show breakpoint always-inserted
1993 Keep breakpoints always inserted in the target, as opposed to inserting
1994 them when resuming the target, and removing them when the target stops.
1995 This option can improve debugger performance on slow remote targets.
1997 set arm fallback-mode (arm|thumb|auto)
1998 show arm fallback-mode
1999 set arm force-mode (arm|thumb|auto)
2001 These commands control how ARM GDB determines whether instructions
2002 are ARM or Thumb. The default for both settings is auto, which uses
2003 the current CPSR value for instructions without symbols; previous
2004 versions of GDB behaved as if "set arm fallback-mode arm".
2006 set disable-randomization
2007 show disable-randomization
2008 Standalone programs run with the virtual address space randomization enabled
2009 by default on some platforms. This option keeps the addresses stable across
2010 multiple debugging sessions.
2014 Control whether other threads are stopped or not when some thread hits
2019 Requests that asynchronous execution is enabled in the target, if available.
2020 In this case, it's possible to resume target in the background, and interact
2021 with GDB while the target is running. "show target-async" displays the
2022 current state of asynchronous execution of the target.
2024 set target-wide-charset
2025 show target-wide-charset
2026 The target-wide-charset is the name of the character set that GDB
2027 uses when printing characters whose type is wchar_t.
2029 set tcp auto-retry (on|off)
2031 set tcp connect-timeout
2032 show tcp connect-timeout
2033 These commands allow GDB to retry failed TCP connections to a remote stub
2034 with a specified timeout period; this is useful if the stub is launched
2035 in parallel with GDB but may not be ready to accept connections immediately.
2037 set libthread-db-search-path
2038 show libthread-db-search-path
2039 Control list of directories which GDB will search for appropriate
2042 set schedule-multiple (on|off)
2043 show schedule-multiple
2044 Allow GDB to resume all threads of all processes or only threads of
2045 the current process.
2049 Use more aggressive caching for accesses to the stack. This improves
2050 performance of remote debugging (particularly backtraces) without
2051 affecting correctness.
2053 set interactive-mode (on|off|auto)
2054 show interactive-mode
2055 Control whether GDB runs in interactive mode (on) or not (off).
2056 When in interactive mode, GDB waits for the user to answer all
2057 queries. Otherwise, GDB does not wait and assumes the default
2058 answer. When set to auto (the default), GDB determines which
2059 mode to use based on the stdin settings.
2064 For program forks, this is replaced by the new more generic `info
2065 inferiors' command. To list checkpoints, you can still use the
2066 `info checkpoints' command, which was an alias for the `info forks'
2070 Replaced by the new `inferior' command. To switch between
2071 checkpoints, you can still use the `restart' command, which was an
2072 alias for the `fork' command.
2075 This is removed, since some targets don't have a notion of
2076 processes. To switch between processes, you can still use the
2077 `inferior' command using GDB's own inferior number.
2080 For program forks, this is replaced by the new more generic `kill
2081 inferior' command. To delete a checkpoint, you can still use the
2082 `delete checkpoint' command, which was an alias for the `delete
2086 For program forks, this is replaced by the new more generic `detach
2087 inferior' command. To detach a checkpoint, you can still use the
2088 `detach checkpoint' command, which was an alias for the `detach
2091 * New native configurations
2093 x86/x86_64 Darwin i[34567]86-*-darwin*
2095 x86_64 MinGW x86_64-*-mingw*
2099 Lattice Mico32 lm32-*
2100 x86 DICOS i[34567]86-*-dicos*
2101 x86_64 DICOS x86_64-*-dicos*
2104 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2105 (mingw32ce) debugging.
2111 These commands were actually not implemented on any target.
2113 *** Changes in GDB 6.8
2115 * New native configurations
2117 NetBSD/hppa hppa*-*netbsd*
2118 Xtensa GNU/Linux xtensa*-*-linux*
2122 NetBSD/hppa hppa*-*-netbsd*
2123 Xtensa GNU/Lunux xtensa*-*-linux*
2125 * Change in command line behavior -- corefiles vs. process ids.
2127 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2128 attaching to process NUMBER fails, GDB no longer attempts to open a
2129 core file named NUMBER. Attaching to a program using the -c option
2130 is no longer supported. Instead, use the '-p' or '--pid' options.
2132 * GDB can now be built as a native debugger for debugging Windows x86
2133 (mingw32) Portable Executable (PE) programs.
2135 * Pending breakpoints no longer change their number when their address
2138 * GDB now supports breakpoints with multiple locations,
2139 including breakpoints on C++ constructors, inside C++ templates,
2140 and in inlined functions.
2142 * GDB's ability to debug optimized code has been improved. GDB more
2143 accurately identifies function bodies and lexical blocks that occupy
2144 more than one contiguous range of addresses.
2146 * Target descriptions can now describe registers for PowerPC.
2148 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2149 registers on PowerPC targets.
2151 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2152 targets even when the libthread_db library is not available.
2154 * The GDB remote stub, gdbserver, now supports the new file transfer
2155 commands (remote put, remote get, and remote delete).
2157 * The GDB remote stub, gdbserver, now supports run and attach in
2158 extended-remote mode.
2160 * hppa*64*-*-hpux11* target broken
2161 The debugger is unable to start a program and fails with the following
2162 error: "Error trying to get information about dynamic linker".
2163 The gdb-6.7 release is also affected.
2165 * GDB now supports the --enable-targets= configure option to allow
2166 building a single GDB executable that supports multiple remote
2167 target architectures.
2169 * GDB now supports debugging C and C++ programs which use the
2170 Decimal Floating Point extension. In addition, the PowerPC target
2171 now has a set of pseudo-registers to inspect decimal float values
2172 stored in two consecutive float registers.
2174 * The -break-insert MI command can optionally create pending
2177 * Improved support for debugging Ada
2178 Many improvements to the Ada language support have been made. These
2180 - Better support for Ada2005 interface types
2181 - Improved handling of arrays and slices in general
2182 - Better support for Taft-amendment types
2183 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2185 - Improved command completion in Ada
2188 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2193 set print frame-arguments (all|scalars|none)
2194 show print frame-arguments
2195 The value of this variable can be changed to control which argument
2196 values should be printed by the debugger when displaying a frame.
2201 Transfer files to and from a remote target, and delete remote files.
2208 Transfer files to and from a remote target, and delete remote files.
2210 * New remote packets
2217 Open, close, read, write, and delete files on the remote system.
2220 Attach to an existing process on the remote system, in extended-remote
2224 Run a new process on the remote system, in extended-remote mode.
2226 *** Changes in GDB 6.7
2228 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2229 bfd, libiberty and opcodes, as revealed by static analysis donated by
2230 Coverity, Inc. (http://scan.coverity.com).
2232 * When looking up multiply-defined global symbols, GDB will now prefer the
2233 symbol definition in the current shared library if it was built using the
2234 -Bsymbolic linker option.
2236 * When the Text User Interface (TUI) is not configured, GDB will now
2237 recognize the -tui command-line option and print a message that the TUI
2240 * The GDB remote stub, gdbserver, now has lower overhead for high
2241 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2243 * GDB for MIPS targets now autodetects whether a remote target provides
2244 32-bit or 64-bit register values.
2246 * Support for C++ member pointers has been improved.
2248 * GDB now understands XML target descriptions, which specify the
2249 target's overall architecture. GDB can read a description from
2250 a local file or over the remote serial protocol.
2252 * Vectors of single-byte data use a new integer type which is not
2253 automatically displayed as character or string data.
2255 * The /s format now works with the print command. It displays
2256 arrays of single-byte integers and pointers to single-byte integers
2259 * Target descriptions can now describe target-specific registers,
2260 for architectures which have implemented the support (currently
2261 only ARM, M68K, and MIPS).
2263 * GDB and the GDB remote stub, gdbserver, now support the XScale
2266 * The GDB remote stub, gdbserver, has been updated to support
2267 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2268 has been rewritten to use the standard GDB remote protocol.
2270 * GDB can now step into C++ functions which are called through thunks.
2272 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2274 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2275 layout. It also supports a TextSeg= and DataSeg= response when only
2276 segment base addresses (rather than offsets) are available.
2278 * The /i format now outputs any trailing branch delay slot instructions
2279 immediately following the last instruction within the count specified.
2281 * The GDB remote protocol "T" stop reply packet now supports a
2282 "library" response. Combined with the new "qXfer:libraries:read"
2283 packet, this response allows GDB to debug shared libraries on targets
2284 where the operating system manages the list of loaded libraries (e.g.
2285 Windows and SymbianOS).
2287 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2288 (DLLs) on Windows and Windows CE targets.
2290 * GDB now supports a faster verification that a .debug file matches its binary
2291 according to its build-id signature, if the signature is present.
2297 Enable or disable hardware flow control (RTS/CTS) on the serial port
2298 when debugging using remote targets.
2300 set mem inaccessible-by-default
2301 show mem inaccessible-by-default
2302 If the target supplies a memory map, for instance via the remote
2303 protocol's "qXfer:memory-map:read" packet, setting this variable
2304 prevents GDB from accessing memory outside the memory map. This
2305 is useful for targets with memory mapped registers or which react
2306 badly to accesses of unmapped address space.
2308 set breakpoint auto-hw
2309 show breakpoint auto-hw
2310 If the target supplies a memory map, for instance via the remote
2311 protocol's "qXfer:memory-map:read" packet, setting this variable
2312 lets GDB use hardware breakpoints automatically for memory regions
2313 where it can not use software breakpoints. This covers both the
2314 "break" command and internal breakpoints used for other commands
2315 including "next" and "finish".
2318 catch exception unhandled
2319 Stop the program execution when Ada exceptions are raised.
2322 Stop the program execution when an Ada assertion failed.
2326 Set an alternate system root for target files. This is a more
2327 general version of "set solib-absolute-prefix", which is now
2328 an alias to "set sysroot".
2331 Provide extended SPU facility status information. This set of
2332 commands is available only when debugging the Cell/B.E. SPU
2335 * New native configurations
2337 OpenBSD/sh sh*-*openbsd*
2340 unset tdesc filename
2342 Use the specified local file as an XML target description, and do
2343 not query the target for its built-in description.
2347 OpenBSD/sh sh*-*-openbsd*
2348 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2349 Toshiba Media Processor mep-elf
2351 * New remote packets
2354 Ignore the specified signals; pass them directly to the debugged program
2355 without stopping other threads or reporting them to GDB.
2357 qXfer:features:read:
2358 Read an XML target description from the target, which describes its
2363 Read or write contents of an spufs file on the target system. These
2364 packets are available only on the Cell/B.E. SPU architecture.
2366 qXfer:libraries:read:
2367 Report the loaded shared libraries. Combined with new "T" packet
2368 response, this packet allows GDB to debug shared libraries on
2369 targets where the operating system manages the list of loaded
2370 libraries (e.g. Windows and SymbianOS).
2374 Support for these obsolete configurations has been removed.
2382 i[34567]86-*-lynxos*
2383 i[34567]86-*-netware*
2384 i[34567]86-*-sco3.2v5*
2385 i[34567]86-*-sco3.2v4*
2387 i[34567]86-*-sysv4.2*
2390 i[34567]86-*-unixware2*
2391 i[34567]86-*-unixware*
2400 * Other removed features
2407 Various m68k-only ROM monitors.
2414 Various Renesas ROM monitors and debugging interfaces for SH and
2419 Support for a Macraigor serial interface to on-chip debugging.
2420 GDB does not directly support the newer parallel or USB
2425 A debug information format. The predecessor to DWARF 2 and
2426 DWARF 3, which are still supported.
2428 Support for the HP aCC compiler on HP-UX/PA-RISC
2430 SOM-encapsulated symbolic debugging information, automatic
2431 invocation of pxdb, and the aCC custom C++ ABI. This does not
2432 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2433 with aCC can still be debugged on an assembly level.
2435 MIPS ".pdr" sections
2437 A MIPS-specific format used to describe stack frame layout
2438 in debugging information.
2442 GDB could work with an older version of Guile to debug
2443 the interpreter and Scheme programs running in it.
2445 set mips stack-arg-size
2446 set mips saved-gpreg-size
2448 Use "set mips abi" to control parameter passing for MIPS.
2450 *** Changes in GDB 6.6
2455 Cell Broadband Engine SPU spu-elf
2457 * GDB can now be configured as a cross-debugger targeting native Windows
2458 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2459 running on a Windows system over TCP/IP to debug Windows programs.
2461 * The GDB remote stub, gdbserver, has been updated to support Windows and
2462 Cygwin debugging. Both single-threaded and multi-threaded programs are
2465 * The "set trust-readonly-sections" command works again. This command was
2466 broken in GDB 6.3, 6.4, and 6.5.
2468 * The "load" command now supports writing to flash memory, if the remote
2469 stub provides the required support.
2471 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2472 longer requires symbolic debug information (e.g. DWARF-2).
2477 unset substitute-path
2478 show substitute-path
2479 Manage a list of substitution rules that GDB uses to rewrite the name
2480 of the directories where the sources are located. This can be useful
2481 for instance when the sources were moved to a different location
2482 between compilation and debugging.
2486 Print each CLI command as it is executed. Each command is prefixed with
2487 a number of `+' symbols representing the nesting depth.
2488 The source command now has a `-v' option to enable the same feature.
2492 The ARM Demon monitor support (RDP protocol, "target rdp").
2494 Kernel Object Display, an embedded debugging feature which only worked with
2495 an obsolete version of Cisco IOS.
2497 The 'set download-write-size' and 'show download-write-size' commands.
2499 * New remote packets
2502 Tell a stub about GDB client features, and request remote target features.
2503 The first feature implemented is PacketSize, which allows the target to
2504 specify the size of packets it can handle - to minimize the number of
2505 packets required and improve performance when connected to a remote
2509 Fetch an OS auxilliary vector from the remote stub. This packet is a
2510 more efficient replacement for qPart:auxv:read.
2512 qXfer:memory-map:read:
2513 Fetch a memory map from the remote stub, including information about
2514 RAM, ROM, and flash memory devices.
2519 Erase and program a flash memory device.
2521 * Removed remote packets
2524 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2525 used it, and only gdbserver implemented it.
2527 *** Changes in GDB 6.5
2531 Renesas M32C/M16C m32c-elf
2533 Morpho Technologies ms1 ms1-elf
2537 init-if-undefined Initialize a convenience variable, but
2538 only if it doesn't already have a value.
2540 The following commands are presently only implemented for native GNU/Linux:
2542 checkpoint Save a snapshot of the program state.
2544 restart <n> Return the program state to a
2545 previously saved state.
2547 info checkpoints List currently saved checkpoints.
2549 delete-checkpoint <n> Delete a previously saved checkpoint.
2551 set|show detach-on-fork Tell gdb whether to detach from a newly
2552 forked process, or to keep debugging it.
2554 info forks List forks of the user program that
2555 are available to be debugged.
2557 fork <n> Switch to debugging one of several
2558 forks of the user program that are
2559 available to be debugged.
2561 delete-fork <n> Delete a fork from the list of forks
2562 that are available to be debugged (and
2563 kill the forked process).
2565 detach-fork <n> Delete a fork from the list of forks
2566 that are available to be debugged (and
2567 allow the process to continue).
2571 Morpho Technologies ms2 ms1-elf
2573 * Improved Windows host support
2575 GDB now builds as a cross debugger hosted on i686-mingw32, including
2576 native console support, and remote communications using either
2577 network sockets or serial ports.
2579 * Improved Modula-2 language support
2581 GDB can now print most types in the Modula-2 syntax. This includes:
2582 basic types, set types, record types, enumerated types, range types,
2583 pointer types and ARRAY types. Procedure var parameters are correctly
2584 printed and hexadecimal addresses and character constants are also
2585 written in the Modula-2 syntax. Best results can be obtained by using
2586 GNU Modula-2 together with the -gdwarf-2 command line option.
2590 The ARM rdi-share module.
2592 The Netware NLM debug server.
2594 *** Changes in GDB 6.4
2596 * New native configurations
2598 OpenBSD/arm arm*-*-openbsd*
2599 OpenBSD/mips64 mips64-*-openbsd*
2603 Morpho Technologies ms1 ms1-elf
2605 * New command line options
2607 --batch-silent As for --batch, but totally silent.
2608 --return-child-result The debugger will exist with the same value
2609 the child (debugged) program exited with.
2610 --eval-command COMMAND, -ex COMMAND
2611 Execute a single GDB CLI command. This may be
2612 specified multiple times and in conjunction
2613 with the --command (-x) option.
2615 * Deprecated commands removed
2617 The following commands, that were deprecated in 2000, have been
2621 set|show arm disassembly-flavor set|show arm disassembler
2622 othernames set arm disassembler
2623 set|show remotedebug set|show debug remote
2624 set|show archdebug set|show debug arch
2625 set|show eventdebug set|show debug event
2628 * New BSD user-level threads support
2630 It is now possible to debug programs using the user-level threads
2631 library on OpenBSD and FreeBSD. Currently supported (target)
2634 FreeBSD/amd64 x86_64-*-freebsd*
2635 FreeBSD/i386 i386-*-freebsd*
2636 OpenBSD/i386 i386-*-openbsd*
2638 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2639 are not yet supported.
2641 * New support for Matsushita MN10300 w/sim added
2642 (Work in progress). mn10300-elf.
2644 * REMOVED configurations and files
2646 VxWorks and the XDR protocol *-*-vxworks
2647 Motorola MCORE mcore-*-*
2648 National Semiconductor NS32000 ns32k-*-*
2650 * New "set print array-indexes" command
2652 After turning this setting "on", GDB prints the index of each element
2653 when displaying arrays. The default is "off" to preserve the previous
2656 * VAX floating point support
2658 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2660 * User-defined command support
2662 In addition to using $arg0..$arg9 for argument passing, it is now possible
2663 to use $argc to determine now many arguments have been passed. See the
2664 section on user-defined commands in the user manual for more information.
2666 *** Changes in GDB 6.3:
2668 * New command line option
2670 GDB now accepts -l followed by a number to set the timeout for remote
2673 * GDB works with GCC -feliminate-dwarf2-dups
2675 GDB now supports a more compact representation of DWARF-2 debug
2676 information using DW_FORM_ref_addr references. These are produced
2677 by GCC with the option -feliminate-dwarf2-dups and also by some
2678 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2679 to use -feliminate-dwarf2-dups.
2681 * Internationalization
2683 When supported by the host system, GDB will be built with
2684 internationalization (libintl). The task of marking up the sources is
2685 continued, we're looking forward to our first translation.
2689 Initial support for debugging programs compiled with the GNAT
2690 implementation of the Ada programming language has been integrated
2691 into GDB. In this release, support is limited to expression evaluation.
2693 * New native configurations
2695 GNU/Linux/m32r m32r-*-linux-gnu
2699 GDB's remote protocol now includes support for the 'p' packet. This
2700 packet is used to fetch individual registers from a remote inferior.
2702 * END-OF-LIFE registers[] compatibility module
2704 GDB's internal register infrastructure has been completely rewritten.
2705 The new infrastructure making possible the implementation of key new
2706 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2709 GDB 6.3 will be the last release to include the the registers[]
2710 compatibility module that allowed out-of-date configurations to
2711 continue to work. This change directly impacts the following
2721 powerpc bdm protocol
2723 Unless there is activity to revive these configurations, they will be
2724 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2726 * OBSOLETE configurations and files
2728 Configurations that have been declared obsolete in this release have
2729 been commented out. Unless there is activity to revive these
2730 configurations, the next release of GDB will have their sources
2731 permanently REMOVED.
2740 *** Changes in GDB 6.2.1:
2742 * MIPS `break main; run' gave an heuristic-fence-post warning
2744 When attempting to run even a simple program, a warning about
2745 heuristic-fence-post being hit would be reported. This problem has
2748 * MIPS IRIX 'long double' crashed GDB
2750 When examining a long double variable, GDB would get a segmentation
2751 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2752 IRIX long double values).
2756 A bug in the VAX stack code was causing problems with the "next"
2757 command. This problem has been fixed.
2759 *** Changes in GDB 6.2:
2761 * Fix for ``many threads''
2763 On GNU/Linux systems that use the NPTL threads library, a program
2764 rapidly creating and deleting threads would confuse GDB leading to the
2767 ptrace: No such process.
2768 thread_db_get_info: cannot get thread info: generic error
2770 This problem has been fixed.
2772 * "-async" and "-noasync" options removed.
2774 Support for the broken "-noasync" option has been removed (it caused
2777 * New ``start'' command.
2779 This command runs the program until the begining of the main procedure.
2781 * New BSD Kernel Data Access Library (libkvm) interface
2783 Using ``target kvm'' it is now possible to debug kernel core dumps and
2784 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2785 platforms. Currently supported (native-only) configurations are:
2787 FreeBSD/amd64 x86_64-*-freebsd*
2788 FreeBSD/i386 i?86-*-freebsd*
2789 NetBSD/i386 i?86-*-netbsd*
2790 NetBSD/m68k m68*-*-netbsd*
2791 NetBSD/sparc sparc-*-netbsd*
2792 OpenBSD/amd64 x86_64-*-openbsd*
2793 OpenBSD/i386 i?86-*-openbsd*
2794 OpenBSD/m68k m68*-openbsd*
2795 OpenBSD/sparc sparc-*-openbsd*
2797 * Signal trampoline code overhauled
2799 Many generic problems with GDB's signal handling code have been fixed.
2800 These include: backtraces through non-contiguous stacks; recognition
2801 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2802 call; backtrace through a signal trampoline; step into and out of
2803 signal handlers; and single-stepping in the signal trampoline.
2805 Please note that kernel bugs are a limiting factor here. These
2806 features have been shown to work on an s390 GNU/Linux system that
2807 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2809 * Cygwin support for DWARF 2 added.
2811 * New native configurations
2813 GNU/Linux/hppa hppa*-*-linux*
2814 OpenBSD/hppa hppa*-*-openbsd*
2815 OpenBSD/m68k m68*-*-openbsd*
2816 OpenBSD/m88k m88*-*-openbsd*
2817 OpenBSD/powerpc powerpc-*-openbsd*
2818 NetBSD/vax vax-*-netbsd*
2819 OpenBSD/vax vax-*-openbsd*
2821 * END-OF-LIFE frame compatibility module
2823 GDB's internal frame infrastructure has been completely rewritten.
2824 The new infrastructure making it possible to support key new features
2825 including DWARF 2 Call Frame Information. To aid in the task of
2826 migrating old configurations to this new infrastructure, a
2827 compatibility module, that allowed old configurations to continue to
2828 work, was also included.
2830 GDB 6.2 will be the last release to include this frame compatibility
2831 module. This change directly impacts the following configurations:
2841 Unless there is activity to revive these configurations, they will be
2842 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2844 * REMOVED configurations and files
2846 Sun 3, running SunOS 3 m68*-*-sunos3*
2847 Sun 3, running SunOS 4 m68*-*-sunos4*
2848 Sun 2, running SunOS 3 m68000-*-sunos3*
2849 Sun 2, running SunOS 4 m68000-*-sunos4*
2850 Motorola 680x0 running LynxOS m68*-*-lynxos*
2851 AT&T 3b1/Unix pc m68*-att-*
2852 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2853 decstation mips-dec-* mips-little-*
2854 riscos mips-*-riscos* mips-*-sysv*
2855 sonymips mips-sony-*
2856 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2858 *** Changes in GDB 6.1.1:
2860 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2862 The TUI (Text-mode User Interface) is now built as part of a default
2863 GDB configuration. It is enabled by either selecting the TUI with the
2864 command line option "-i=tui" or by running the separate "gdbtui"
2865 program. For more information on the TUI, see the manual "Debugging
2868 * Pending breakpoint support (also included in GDB 6.1)
2870 Support has been added to allow you to specify breakpoints in shared
2871 libraries that have not yet been loaded. If a breakpoint location
2872 cannot be found, and the "breakpoint pending" option is set to auto,
2873 GDB queries you if you wish to make the breakpoint pending on a future
2874 shared-library load. If and when GDB resolves the breakpoint symbol,
2875 the pending breakpoint is removed as one or more regular breakpoints
2878 Pending breakpoints are very useful for GCJ Java debugging.
2880 * Fixed ISO-C build problems
2882 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2883 non ISO-C code that stopped them being built using a more strict ISO-C
2884 compiler (e.g., IBM's C compiler).
2886 * Fixed build problem on IRIX 5
2888 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2889 wasn't able to compile compile on an IRIX 5 system.
2891 * Added execute permission to gdb/gdbserver/configure
2893 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2894 permission. This bug would cause configure to fail on a number of
2895 systems (Solaris, IRIX). Ref: server/519.
2897 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2899 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2900 has been updated to use constant array sizes.
2902 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2904 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2905 its generated DWARF Call Frame Info. This encoding was causing GDB to
2906 panic, that panic has been fixed. Ref: gdb/1628.
2908 * Fixed a problem when examining parameters in shared library code.
2910 When examining parameters in optimized shared library code generated
2911 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2912 not available''. GDB now correctly displays the variable's value.
2914 *** Changes in GDB 6.1:
2916 * Removed --with-mmalloc
2918 Support for the mmalloc memory manager has been removed, as it
2919 conflicted with the internal gdb byte cache.
2921 * Changes in AMD64 configurations
2923 The AMD64 target now includes the %cs and %ss registers. As a result
2924 the AMD64 remote protocol has changed; this affects the floating-point
2925 and SSE registers. If you rely on those registers for your debugging,
2926 you should upgrade gdbserver on the remote side.
2928 * Revised SPARC target
2930 The SPARC target has been completely revised, incorporating the
2931 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2932 support for LynxOS and SunOS 4 has been dropped. Calling functions
2933 from within GDB on operating systems with a non-executable stack
2934 (Solaris, OpenBSD) now works.
2938 GDB has a new C++ demangler which does a better job on the mangled
2939 names generated by current versions of g++. It also runs faster, so
2940 with this and other changes gdb should now start faster on large C++
2943 * DWARF 2 Location Expressions
2945 GDB support for location expressions has been extended to support function
2946 arguments and frame bases. Older versions of GDB could crash when they
2949 * C++ nested types and namespaces
2951 GDB's support for nested types and namespaces in C++ has been
2952 improved, especially if you use the DWARF 2 debugging format. (This
2953 is the default for recent versions of GCC on most platforms.)
2954 Specifically, if you have a class "Inner" defined within a class or
2955 namespace "Outer", then GDB realizes that the class's name is
2956 "Outer::Inner", not simply "Inner". This should greatly reduce the
2957 frequency of complaints about not finding RTTI symbols. In addition,
2958 if you are stopped at inside of a function defined within a namespace,
2959 GDB modifies its name lookup accordingly.
2961 * New native configurations
2963 NetBSD/amd64 x86_64-*-netbsd*
2964 OpenBSD/amd64 x86_64-*-openbsd*
2965 OpenBSD/alpha alpha*-*-openbsd*
2966 OpenBSD/sparc sparc-*-openbsd*
2967 OpenBSD/sparc64 sparc64-*-openbsd*
2969 * New debugging protocols
2971 M32R with SDI protocol m32r-*-elf*
2973 * "set prompt-escape-char" command deleted.
2975 The command "set prompt-escape-char" has been deleted. This command,
2976 and its very obscure effet on GDB's prompt, was never documented,
2977 tested, nor mentioned in the NEWS file.
2979 * OBSOLETE configurations and files
2981 Configurations that have been declared obsolete in this release have
2982 been commented out. Unless there is activity to revive these
2983 configurations, the next release of GDB will have their sources
2984 permanently REMOVED.
2986 Sun 3, running SunOS 3 m68*-*-sunos3*
2987 Sun 3, running SunOS 4 m68*-*-sunos4*
2988 Sun 2, running SunOS 3 m68000-*-sunos3*
2989 Sun 2, running SunOS 4 m68000-*-sunos4*
2990 Motorola 680x0 running LynxOS m68*-*-lynxos*
2991 AT&T 3b1/Unix pc m68*-att-*
2992 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2993 decstation mips-dec-* mips-little-*
2994 riscos mips-*-riscos* mips-*-sysv*
2995 sonymips mips-sony-*
2996 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2998 * REMOVED configurations and files
3000 SGI Irix-4.x mips-sgi-irix4 or iris4
3001 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3002 Z8000 simulator z8k-zilog-none or z8ksim
3003 Matsushita MN10200 w/simulator mn10200-*-*
3004 H8/500 simulator h8500-hitachi-hms or h8500hms
3005 HP/PA running BSD hppa*-*-bsd*
3006 HP/PA running OSF/1 hppa*-*-osf*
3007 HP/PA Pro target hppa*-*-pro*
3008 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3009 386BSD i[3456]86-*-bsd*
3010 Sequent family i[3456]86-sequent-sysv4*
3011 i[3456]86-sequent-sysv*
3012 i[3456]86-sequent-bsd*
3013 SPARC running LynxOS sparc-*-lynxos*
3014 SPARC running SunOS 4 sparc-*-sunos4*
3015 Tsqware Sparclet sparclet-*-*
3016 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3018 *** Changes in GDB 6.0:
3022 Support for debugging the Objective-C programming language has been
3023 integrated into GDB.
3025 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3027 DWARF 2's Call Frame Information makes available compiler generated
3028 information that more exactly describes the program's run-time stack.
3029 By using this information, GDB is able to provide more robust stack
3032 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3033 have been updated to use a new backtrace mechanism which includes
3034 DWARF 2 CFI support.
3038 GDB's remote protocol has been extended to include support for hosted
3039 file I/O (where the remote target uses GDB's file system). See GDB's
3040 remote protocol documentation for details.
3042 * All targets using the new architecture framework.
3044 All of GDB's targets have been updated to use the new internal
3045 architecture framework. The way is now open for future GDB releases
3046 to include cross-architecture native debugging support (i386 on amd64,
3049 * GNU/Linux's Thread Local Storage (TLS)
3051 GDB now includes support for for the GNU/Linux implementation of
3052 per-thread variables.
3054 * GNU/Linux's Native POSIX Thread Library (NPTL)
3056 GDB's thread code has been updated to work with either the new
3057 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3059 * Separate debug info.
3061 GDB, in conjunction with BINUTILS, now supports a mechanism for
3062 automatically loading debug information from a separate file. Instead
3063 of shipping full debug and non-debug versions of system libraries,
3064 system integrators can now instead ship just the stripped libraries
3065 and optional debug files.
3067 * DWARF 2 Location Expressions
3069 DWARF 2 Location Expressions allow the compiler to more completely
3070 describe the location of variables (even in optimized code) to the
3073 GDB now includes preliminary support for location expressions (support
3074 for DW_OP_piece is still missing).
3078 A number of long standing bugs that caused GDB to die while starting a
3079 Java application have been fixed. GDB's Java support is now
3080 considered "useable".
3082 * GNU/Linux support for fork, vfork, and exec.
3084 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3085 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3088 * GDB supports logging output to a file
3090 There are two new commands, "set logging" and "show logging", which can be
3091 used to capture GDB's output to a file.
3093 * The meaning of "detach" has changed for gdbserver
3095 The "detach" command will now resume the application, as documented. To
3096 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3099 * d10v, m68hc11 `regs' command deprecated
3101 The `info registers' command has been updated so that it displays the
3102 registers using a format identical to the old `regs' command.
3106 A new command, "maint set profile on/off", has been added. This command can
3107 be used to enable or disable profiling while running GDB, to profile a
3108 session or a set of commands. In addition there is a new configure switch,
3109 "--enable-profiling", which will cause GDB to be compiled with profiling
3110 data, for more informative profiling results.
3112 * Default MI syntax changed to "mi2".
3114 The default MI (machine interface) syntax, enabled by the command line
3115 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3116 "mi1", can be enabled by specifying the option "-i=mi1".
3118 Support for the original "mi0" syntax (included in GDB 5.0) has been
3121 Fix for gdb/192: removed extraneous space when displaying frame level.
3122 Fix for gdb/672: update changelist is now output in mi list format.
3123 Fix for gdb/702: a -var-assign that updates the value now shows up
3124 in a subsequent -var-update.
3126 * New native configurations.
3128 FreeBSD/amd64 x86_64-*-freebsd*
3130 * Multi-arched targets.
3132 HP/PA HPUX11 hppa*-*-hpux*
3133 Renesas M32R/D w/simulator m32r-*-elf*
3135 * OBSOLETE configurations and files
3137 Configurations that have been declared obsolete in this release have
3138 been commented out. Unless there is activity to revive these
3139 configurations, the next release of GDB will have their sources
3140 permanently REMOVED.
3142 Z8000 simulator z8k-zilog-none or z8ksim
3143 Matsushita MN10200 w/simulator mn10200-*-*
3144 H8/500 simulator h8500-hitachi-hms or h8500hms
3145 HP/PA running BSD hppa*-*-bsd*
3146 HP/PA running OSF/1 hppa*-*-osf*
3147 HP/PA Pro target hppa*-*-pro*
3148 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3149 Sequent family i[3456]86-sequent-sysv4*
3150 i[3456]86-sequent-sysv*
3151 i[3456]86-sequent-bsd*
3152 Tsqware Sparclet sparclet-*-*
3153 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3155 * REMOVED configurations and files
3158 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3159 IBM AIX PS/2 i[3456]86-*-aix
3160 i386 running Mach 3.0 i[3456]86-*-mach3*
3161 i386 running Mach i[3456]86-*-mach*
3162 i386 running OSF/1 i[3456]86-*osf1mk*
3163 HP/Apollo 68k Family m68*-apollo*-sysv*,
3165 m68*-hp-bsd*, m68*-hp-hpux*
3166 Argonaut Risc Chip (ARC) arc-*-*
3167 Mitsubishi D30V d30v-*-*
3168 Fujitsu FR30 fr30-*-elf*
3169 OS/9000 i[34]86-*-os9k
3170 I960 with MON960 i960-*-coff
3172 * MIPS $fp behavior changed
3174 The convenience variable $fp, for the MIPS, now consistently returns
3175 the address of the current frame's base. Previously, depending on the
3176 context, $fp could refer to either $sp or the current frame's base
3177 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3178 The GNU Source-Level Debugger''.
3180 *** Changes in GDB 5.3:
3182 * GNU/Linux shared library multi-threaded performance improved.
3184 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3185 `/proc', in preference to `ptrace' for memory reads. This may result
3186 in an improvement in the start-up time of multi-threaded, shared
3187 library applications when run under GDB. One GDB user writes: ``loads
3188 shared libs like mad''.
3190 * ``gdbserver'' now supports multi-threaded applications on some targets
3192 Support for debugging multi-threaded applications which use
3193 the GNU/Linux LinuxThreads package has been added for
3194 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3195 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3197 * GDB now supports C/C++ preprocessor macros.
3199 GDB now expands preprocessor macro invocations in C/C++ expressions,
3200 and provides various commands for showing macro definitions and how
3203 The new command `macro expand EXPRESSION' expands any macro
3204 invocations in expression, and shows the result.
3206 The new command `show macro MACRO-NAME' shows the definition of the
3207 macro named MACRO-NAME, and where it was defined.
3209 Most compilers don't include information about macros in the debugging
3210 information by default. In GCC 3.1, for example, you need to compile
3211 your program with the options `-gdwarf-2 -g3'. If the macro
3212 information is present in the executable, GDB will read it.
3214 * Multi-arched targets.
3216 DEC Alpha (partial) alpha*-*-*
3217 DEC VAX (partial) vax-*-*
3219 National Semiconductor NS32000 (partial) ns32k-*-*
3220 Motorola 68000 (partial) m68k-*-*
3221 Motorola MCORE mcore-*-*
3225 Fujitsu FRV architecture added by Red Hat frv*-*-*
3228 * New native configurations
3230 Alpha NetBSD alpha*-*-netbsd*
3231 SH NetBSD sh*-*-netbsdelf*
3232 MIPS NetBSD mips*-*-netbsd*
3233 UltraSPARC NetBSD sparc64-*-netbsd*
3235 * OBSOLETE configurations and files
3237 Configurations that have been declared obsolete in this release have
3238 been commented out. Unless there is activity to revive these
3239 configurations, the next release of GDB will have their sources
3240 permanently REMOVED.
3242 Mitsubishi D30V d30v-*-*
3243 OS/9000 i[34]86-*-os9k
3244 IBM AIX PS/2 i[3456]86-*-aix
3245 Fujitsu FR30 fr30-*-elf*
3246 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3247 Argonaut Risc Chip (ARC) arc-*-*
3248 i386 running Mach 3.0 i[3456]86-*-mach3*
3249 i386 running Mach i[3456]86-*-mach*
3250 i386 running OSF/1 i[3456]86-*osf1mk*
3251 HP/Apollo 68k Family m68*-apollo*-sysv*,
3253 m68*-hp-bsd*, m68*-hp-hpux*
3254 I960 with MON960 i960-*-coff
3256 * OBSOLETE languages
3258 CHILL, a Pascal like language used by telecommunications companies.
3260 * REMOVED configurations and files
3262 AMD 29k family via UDI a29k-amd-udi, udi29k
3263 A29K VxWorks a29k-*-vxworks
3264 AMD 29000 embedded, using EBMON a29k-none-none
3265 AMD 29000 embedded with COFF a29k-none-coff
3266 AMD 29000 embedded with a.out a29k-none-aout
3268 testsuite/gdb.hp/gdb.threads-hp/ directory
3270 * New command "set max-user-call-depth <nnn>"
3272 This command allows the user to limit the call depth of user-defined
3273 commands. The default is 1024.
3275 * Changes in FreeBSD/i386 native debugging.
3277 Support for the "generate-core-file" has been added.
3279 * New commands "dump", "append", and "restore".
3281 These commands allow data to be copied from target memory
3282 to a bfd-format or binary file (dump and append), and back
3283 from a file into memory (restore).
3285 * Improved "next/step" support on multi-processor Alpha Tru64.
3287 The previous single-step mechanism could cause unpredictable problems,
3288 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3289 of a software single-step mechanism prevents this.
3291 *** Changes in GDB 5.2.1:
3299 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3300 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3301 Fix, by Joel Brobecker imported from mainline.
3303 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3304 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3305 Fix, by Fred Fish, imported from mainline.
3307 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3308 Surprisingly enough, it works now.
3309 By Michal Ludvig, imported from mainline.
3311 i386 hardware watchpoint support:
3312 avoid misses on second run for some targets.
3313 By Pierre Muller, imported from mainline.
3315 *** Changes in GDB 5.2:
3317 * New command "set trust-readonly-sections on[off]".
3319 This command is a hint that tells gdb that read-only sections
3320 really are read-only (ie. that their contents will not change).
3321 In this mode, gdb will go to the object file rather than the
3322 target to read memory from read-only sections (such as ".text").
3323 This can be a significant performance improvement on some
3324 (notably embedded) targets.
3326 * New command "generate-core-file" (or "gcore").
3328 This new gdb command allows the user to drop a core file of the child
3329 process state at any time. So far it's been implemented only for
3330 GNU/Linux and Solaris, but should be relatively easily ported to other
3331 hosts. Argument is core file name (defaults to core.<pid>).
3333 * New command line option
3335 GDB now accepts --pid or -p followed by a process id.
3337 * Change in command line behavior -- corefiles vs. process ids.
3339 There is a subtle behavior in the way in which GDB handles
3340 command line arguments. The first non-flag argument is always
3341 a program to debug, but the second non-flag argument may either
3342 be a corefile or a process id. Previously, GDB would attempt to
3343 open the second argument as a corefile, and if that failed, would
3344 issue a superfluous error message and then attempt to attach it as
3345 a process. Now, if the second argument begins with a non-digit,
3346 it will be treated as a corefile. If it begins with a digit,
3347 GDB will attempt to attach it as a process, and if no such process
3348 is found, will then attempt to open it as a corefile.
3350 * Changes in ARM configurations.
3352 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3353 configuration is fully multi-arch.
3355 * New native configurations
3357 ARM NetBSD arm*-*-netbsd*
3358 x86 OpenBSD i[3456]86-*-openbsd*
3359 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3360 Sparc64 running FreeBSD sparc64-*-freebsd*
3364 Sanyo XStormy16 xstormy16-elf
3366 * OBSOLETE configurations and files
3368 Configurations that have been declared obsolete in this release have
3369 been commented out. Unless there is activity to revive these
3370 configurations, the next release of GDB will have their sources
3371 permanently REMOVED.
3373 AMD 29k family via UDI a29k-amd-udi, udi29k
3374 A29K VxWorks a29k-*-vxworks
3375 AMD 29000 embedded, using EBMON a29k-none-none
3376 AMD 29000 embedded with COFF a29k-none-coff
3377 AMD 29000 embedded with a.out a29k-none-aout
3379 testsuite/gdb.hp/gdb.threads-hp/ directory
3381 * REMOVED configurations and files
3383 TI TMS320C80 tic80-*-*
3385 PowerPC Solaris powerpcle-*-solaris*
3386 PowerPC Windows NT powerpcle-*-cygwin32
3387 PowerPC Netware powerpc-*-netware*
3388 Harris/CXUX m88k m88*-harris-cxux*
3389 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3390 ns32k-utek-sysv* ns32k-utek-*
3391 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3392 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3393 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3394 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3395 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3397 * Changes to command line processing
3399 The new `--args' feature can be used to specify command-line arguments
3400 for the inferior from gdb's command line.
3402 * Changes to key bindings
3404 There is a new `operate-and-get-next' function bound to `C-o'.
3406 *** Changes in GDB 5.1.1
3408 Fix compile problem on DJGPP.
3410 Fix a problem with floating-point registers on the i386 being
3413 Fix to stop GDB crashing on .debug_str debug info.
3415 Numerous documentation fixes.
3417 Numerous testsuite fixes.
3419 *** Changes in GDB 5.1:
3421 * New native configurations
3423 Alpha FreeBSD alpha*-*-freebsd*
3424 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3425 MIPS GNU/Linux mips*-*-linux*
3426 MIPS SGI Irix 6.x mips*-sgi-irix6*
3427 ia64 AIX ia64-*-aix*
3428 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3432 Motorola 68HC11 and 68HC12 m68hc11-elf
3434 UltraSparc running GNU/Linux sparc64-*-linux*
3436 * OBSOLETE configurations and files
3438 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3439 Harris/CXUX m88k m88*-harris-cxux*
3440 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3441 ns32k-utek-sysv* ns32k-utek-*
3442 TI TMS320C80 tic80-*-*
3444 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3445 PowerPC Solaris powerpcle-*-solaris*
3446 PowerPC Windows NT powerpcle-*-cygwin32
3447 PowerPC Netware powerpc-*-netware*
3448 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3449 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3450 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3451 Apple Macintosh (MPW) host N/A
3453 stuff.c (Program to stuff files into a specially prepared space in kdb)
3454 kdb-start.c (Main loop for the standalone kernel debugger)
3456 Configurations that have been declared obsolete in this release have
3457 been commented out. Unless there is activity to revive these
3458 configurations, the next release of GDB will have their sources
3459 permanently REMOVED.
3461 * REMOVED configurations and files
3463 Altos 3068 m68*-altos-*
3464 Convex c1-*-*, c2-*-*
3466 ARM RISCix arm-*-* (as host)
3470 * GDB has been converted to ISO C.
3472 GDB's source code has been converted to ISO C. In particular, the
3473 sources are fully protoized, and rely on standard headers being
3478 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3480 * The MI enabled by default.
3482 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3483 revised and enabled by default. Packages which use GDB as a debugging
3484 engine behind a UI or another front end are encouraged to switch to
3485 using the GDB/MI interface, instead of the old annotations interface
3486 which is now deprecated.
3488 * Support for debugging Pascal programs.
3490 GDB now includes support for debugging Pascal programs. The following
3491 main features are supported:
3493 - Pascal-specific data types such as sets;
3495 - automatic recognition of Pascal sources based on file-name
3498 - Pascal-style display of data types, variables, and functions;
3500 - a Pascal expression parser.
3502 However, some important features are not yet supported.
3504 - Pascal string operations are not supported at all;
3506 - there are some problems with boolean types;
3508 - Pascal type hexadecimal constants are not supported
3509 because they conflict with the internal variables format;
3511 - support for Pascal objects and classes is not full yet;
3513 - unlike Pascal, GDB is case-sensitive for symbol names.
3515 * Changes in completion.
3517 Commands such as `shell', `run' and `set args', which pass arguments
3518 to inferior programs, now complete on file names, similar to what
3519 users expect at the shell prompt.
3521 Commands which accept locations, such as `disassemble', `print',
3522 `breakpoint', `until', etc. now complete on filenames as well as
3523 program symbols. Thus, if you type "break foob TAB", and the source
3524 files linked into the programs include `foobar.c', that file name will
3525 be one of the candidates for completion. However, file names are not
3526 considered for completion after you typed a colon that delimits a file
3527 name from a name of a function in that file, as in "break foo.c:bar".
3529 `set demangle-style' completes on available demangling styles.
3531 * New platform-independent commands:
3533 It is now possible to define a post-hook for a command as well as a
3534 hook that runs before the command. For more details, see the
3535 documentation of `hookpost' in the GDB manual.
3537 * Changes in GNU/Linux native debugging.
3539 Support for debugging multi-threaded programs has been completely
3540 revised for all platforms except m68k and sparc. You can now debug as
3541 many threads as your system allows you to have.
3543 Attach/detach is supported for multi-threaded programs.
3545 Support for SSE registers was added for x86. This doesn't work for
3546 multi-threaded programs though.
3548 * Changes in MIPS configurations.
3550 Multi-arch support is enabled for all MIPS configurations.
3552 GDB can now be built as native debugger on SGI Irix 6.x systems for
3553 debugging n32 executables. (Debugging 64-bit executables is not yet
3556 * Unified support for hardware watchpoints in all x86 configurations.
3558 Most (if not all) native x86 configurations support hardware-assisted
3559 breakpoints and watchpoints in a unified manner. This support
3560 implements debug register sharing between watchpoints, which allows to
3561 put a virtually infinite number of watchpoints on the same address,
3562 and also supports watching regions up to 16 bytes with several debug
3565 The new maintenance command `maintenance show-debug-regs' toggles
3566 debugging print-outs in functions that insert, remove, and test
3567 watchpoints and hardware breakpoints.
3569 * Changes in the DJGPP native configuration.
3571 New command ``info dos sysinfo'' displays assorted information about
3572 the CPU, OS, memory, and DPMI server.
3574 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3575 display information about segment descriptors stored in GDT, LDT, and
3578 New commands ``info dos pde'' and ``info dos pte'' display entries
3579 from Page Directory and Page Tables (for now works with CWSDPMI only).
3580 New command ``info dos address-pte'' displays the Page Table entry for
3581 a given linear address.
3583 GDB can now pass command lines longer than 126 characters to the
3584 program being debugged (requires an update to the libdbg.a library
3585 which is part of the DJGPP development kit).
3587 DWARF2 debug info is now supported.
3589 It is now possible to `step' and `next' through calls to `longjmp'.
3591 * Changes in documentation.
3593 All GDB documentation was converted to GFDL, the GNU Free
3594 Documentation License.
3596 Tracepoints-related commands are now fully documented in the GDB
3599 TUI, the Text-mode User Interface, is now documented in the manual.
3601 Tracepoints-related commands are now fully documented in the GDB
3604 The "GDB Internals" manual now has an index. It also includes
3605 documentation of `ui_out' functions, GDB coding standards, x86
3606 hardware watchpoints, and memory region attributes.
3608 * GDB's version number moved to ``version.in''
3610 The Makefile variable VERSION has been replaced by the file
3611 ``version.in''. People creating GDB distributions should update the
3612 contents of this file.
3616 GUD support is now a standard part of the EMACS distribution.
3618 *** Changes in GDB 5.0:
3620 * Improved support for debugging FP programs on x86 targets
3622 Unified and much-improved support for debugging floating-point
3623 programs on all x86 targets. In particular, ``info float'' now
3624 displays the FP registers in the same format on all x86 targets, with
3625 greater level of detail.
3627 * Improvements and bugfixes in hardware-assisted watchpoints
3629 It is now possible to watch array elements, struct members, and
3630 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3631 on x86 targets no longer erroneously trigger when the address is
3634 * Improvements in the native DJGPP version of GDB
3636 The distribution now includes all the scripts and auxiliary files
3637 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3638 machines ``out of the box''.
3640 The DJGPP version can now debug programs that use signals. It is
3641 possible to catch signals that happened in the debuggee, deliver
3642 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3643 would kill the program being debugged.) Programs that hook hardware
3644 interrupts (keyboard, timer, etc.) can also be debugged.
3646 It is now possible to debug DJGPP programs that redirect their
3647 standard handles or switch them to raw (as opposed to cooked) mode, or
3648 even close them. The command ``run < foo > bar'' works as expected,
3649 and ``info terminal'' reports useful information about the debuggee's
3650 terminal, including raw/cooked mode, redirection, etc.
3652 The DJGPP version now uses termios functions for console I/O, which
3653 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3656 DOS-style file names with drive letters are now fully supported by
3659 It is now possible to debug DJGPP programs that switch their working
3660 directory. It is also possible to rerun the debuggee any number of
3661 times without restarting GDB; thus, you can use the same setup,
3662 breakpoints, etc. for many debugging sessions.
3664 * New native configurations
3666 ARM GNU/Linux arm*-*-linux*
3667 PowerPC GNU/Linux powerpc-*-linux*
3671 Motorola MCore mcore-*-*
3672 x86 VxWorks i[3456]86-*-vxworks*
3673 PowerPC VxWorks powerpc-*-vxworks*
3674 TI TMS320C80 tic80-*-*
3676 * OBSOLETE configurations
3678 Altos 3068 m68*-altos-*
3679 Convex c1-*-*, c2-*-*
3681 ARM RISCix arm-*-* (as host)
3684 Configurations that have been declared obsolete will be commented out,
3685 but the code will be left in place. If there is no activity to revive
3686 these configurations before the next release of GDB, the sources will
3687 be permanently REMOVED.
3689 * Gould support removed
3691 Support for the Gould PowerNode and NP1 has been removed.
3693 * New features for SVR4
3695 On SVR4 native platforms (such as Solaris), if you attach to a process
3696 without first loading a symbol file, GDB will now attempt to locate and
3697 load symbols from the running process's executable file.
3699 * Many C++ enhancements
3701 C++ support has been greatly improved. Overload resolution now works properly
3702 in almost all cases. RTTI support is on the way.
3704 * Remote targets can connect to a sub-program
3706 A popen(3) style serial-device has been added. This device starts a
3707 sub-process (such as a stand-alone simulator) and then communicates
3708 with that. The sub-program to run is specified using the syntax
3709 ``|<program> <args>'' vis:
3711 (gdb) set remotedebug 1
3712 (gdb) target extended-remote |mn10300-elf-sim program-args
3714 * MIPS 64 remote protocol
3716 A long standing bug in the mips64 remote protocol where by GDB
3717 expected certain 32 bit registers (ex SR) to be transfered as 32
3718 instead of 64 bits has been fixed.
3720 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3721 added to provide backward compatibility with older versions of GDB.
3723 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3725 The command ``set remotebinarydownload'' command has been replaced by
3726 ``set remote X-packet''. Other commands in ``set remote'' family
3727 include ``set remote P-packet''.
3729 * Breakpoint commands accept ranges.
3731 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3732 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3733 ``tracepoint passcount'' also accepts a range of tracepoints.
3735 * ``apropos'' command added.
3737 The ``apropos'' command searches through command names and
3738 documentation strings, printing out matches, making it much easier to
3739 try to find a command that does what you are looking for.
3743 A new machine oriented interface (MI) has been added to GDB. This
3744 interface is designed for debug environments running GDB as a separate
3745 process. This is part of the long term libGDB project. See the
3746 "GDB/MI" chapter of the GDB manual for further information. It can be
3747 enabled by configuring with:
3749 .../configure --enable-gdbmi
3751 *** Changes in GDB-4.18:
3753 * New native configurations
3755 HP-UX 10.20 hppa*-*-hpux10.20
3756 HP-UX 11.x hppa*-*-hpux11.0*
3757 M68K GNU/Linux m68*-*-linux*
3761 Fujitsu FR30 fr30-*-elf*
3762 Intel StrongARM strongarm-*-*
3763 Mitsubishi D30V d30v-*-*
3765 * OBSOLETE configurations
3767 Gould PowerNode, NP1 np1-*-*, pn-*-*
3769 Configurations that have been declared obsolete will be commented out,
3770 but the code will be left in place. If there is no activity to revive
3771 these configurations before the next release of GDB, the sources will
3772 be permanently REMOVED.
3776 As a compatibility experiment, GDB's source files buildsym.h and
3777 buildsym.c have been converted to pure standard C, no longer
3778 containing any K&R compatibility code. We believe that all systems in
3779 use today either come with a standard C compiler, or have a GCC port
3780 available. If this is not true, please report the affected
3781 configuration to bug-gdb@gnu.org immediately. See the README file for
3782 information about getting a standard C compiler if you don't have one
3787 GDB now uses readline 2.2.
3789 * set extension-language
3791 You can now control the mapping between filename extensions and source
3792 languages by using the `set extension-language' command. For instance,
3793 you can ask GDB to treat .c files as C++ by saying
3794 set extension-language .c c++
3795 The command `info extensions' lists all of the recognized extensions
3796 and their associated languages.
3798 * Setting processor type for PowerPC and RS/6000
3800 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3801 you can use the `set processor' command to specify what variant of the
3802 PowerPC family you are debugging. The command
3806 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3807 following PowerPC and RS6000 variants:
3809 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3810 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3812 403GC IBM PowerPC 403GC
3813 505 Motorola PowerPC 505
3814 860 Motorola PowerPC 860 or 850
3815 601 Motorola PowerPC 601
3816 602 Motorola PowerPC 602
3817 603 Motorola/IBM PowerPC 603 or 603e
3818 604 Motorola PowerPC 604 or 604e
3819 750 Motorola/IBM PowerPC 750 or 750
3821 At the moment, this command just tells GDB what to name the
3822 special-purpose processor registers. Since almost all the affected
3823 registers are inaccessible to user-level programs, this command is
3824 only useful for remote debugging in its present form.
3828 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3829 more extensive support for HP-UX. Added features include shared
3830 library support, kernel threads and hardware watchpoints for 11.00,
3831 support for HP's ANSI C and C++ compilers, and a compatibility mode
3832 for xdb and dbx commands.
3836 HP's donation includes the new concept of catchpoints, which is a
3837 generalization of the old catch command. On HP-UX, it is now possible
3838 to catch exec, fork, and vfork, as well as library loading.
3840 This means that the existing catch command has changed; its first
3841 argument now specifies the type of catch to be set up. See the
3842 output of "help catch" for a list of catchpoint types.
3844 * Debugging across forks
3846 On HP-UX, you can choose which process to debug when a fork() happens
3851 HP has donated a curses-based terminal user interface (TUI). To get
3852 it, build with --enable-tui. Although this can be enabled for any
3853 configuration, at present it only works for native HP debugging.
3855 * GDB remote protocol additions
3857 A new protocol packet 'X' that writes binary data is now available.
3858 Default behavior is to try 'X', then drop back to 'M' if the stub
3859 fails to respond. The settable variable `remotebinarydownload'
3860 allows explicit control over the use of 'X'.
3862 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3863 full 64-bit address. The command
3865 set remoteaddresssize 32
3867 can be used to revert to the old behaviour. For existing remote stubs
3868 the change should not be noticed, as the additional address information
3871 In order to assist in debugging stubs, you may use the maintenance
3872 command `packet' to send any text string to the stub. For instance,
3874 maint packet heythere
3876 sends the packet "$heythere#<checksum>". Note that it is very easy to
3877 disrupt a debugging session by sending the wrong packet at the wrong
3880 The compare-sections command allows you to compare section data on the
3881 target to what is in the executable file without uploading or
3882 downloading, by comparing CRC checksums.
3884 * Tracing can collect general expressions
3886 You may now collect general expressions at tracepoints. This requires
3887 further additions to the target-side stub; see tracepoint.c and
3888 doc/agentexpr.texi for further details.
3890 * mask-address variable for Mips
3892 For Mips targets, you may control the zeroing of the upper 32 bits of
3893 a 64-bit address by entering `set mask-address on'. This is mainly
3894 of interest to users of embedded R4xxx and R5xxx processors.
3896 * Higher serial baud rates
3898 GDB's serial code now allows you to specify baud rates 57600, 115200,
3899 230400, and 460800 baud. (Note that your host system may not be able
3900 to achieve all of these rates.)
3904 The i960 configuration now includes an initial implementation of a
3905 builtin simulator, contributed by Jim Wilson.
3908 *** Changes in GDB-4.17:
3910 * New native configurations
3912 Alpha GNU/Linux alpha*-*-linux*
3913 Unixware 2.x i[3456]86-unixware2*
3914 Irix 6.x mips*-sgi-irix6*
3915 PowerPC GNU/Linux powerpc-*-linux*
3916 PowerPC Solaris powerpcle-*-solaris*
3917 Sparc GNU/Linux sparc-*-linux*
3918 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3922 Argonaut Risc Chip (ARC) arc-*-*
3923 Hitachi H8/300S h8300*-*-*
3924 Matsushita MN10200 w/simulator mn10200-*-*
3925 Matsushita MN10300 w/simulator mn10300-*-*
3926 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3927 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3928 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3929 Mitsubishi D10V w/simulator d10v-*-*
3930 Mitsubishi M32R/D w/simulator m32r-*-elf*
3931 Tsqware Sparclet sparclet-*-*
3932 NEC V850 w/simulator v850-*-*
3934 * New debugging protocols
3936 ARM with RDI protocol arm*-*-*
3937 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3938 DDB and LSI variants of PMON protocol mips*-*-*
3939 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3940 PowerPC with SDS protocol powerpc{,le}-*-eabi
3941 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3945 All configurations can now understand and use the DWARF 2 debugging
3946 format. The choice is automatic, if the symbol file contains DWARF 2
3951 GDB now includes basic Java language support. This support is
3952 only useful with Java compilers that produce native machine code.
3954 * solib-absolute-prefix and solib-search-path
3956 For SunOS and SVR4 shared libraries, you may now set the prefix for
3957 loading absolute shared library symbol files, and the search path for
3958 locating non-absolute shared library symbol files.
3960 * Live range splitting
3962 GDB can now effectively debug code for which GCC has performed live
3963 range splitting as part of its optimization. See gdb/doc/LRS for
3964 more details on the expected format of the stabs information.
3968 GDB's support for the GNU Hurd, including thread debugging, has been
3969 updated to work with current versions of the Hurd.
3973 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3974 instruction set. ARM GDB automatically detects when Thumb
3975 instructions are in use, and adjusts disassembly and backtracing
3980 GDB's MIPS target configurations now handle the MIP16 16-bit
3985 GDB now includes support for overlays; if an executable has been
3986 linked such that multiple sections are based at the same address, GDB
3987 will decide which section to use for symbolic info. You can choose to
3988 control the decision manually, using overlay commands, or implement
3989 additional target-side support and use "overlay load-target" to bring
3990 in the overlay mapping. Do "help overlay" for more detail.
3994 The command "info symbol <address>" displays information about
3995 the symbol at the specified address.
3999 The standard remote protocol now includes an extension that allows
4000 asynchronous collection and display of trace data. This requires
4001 extensive support in the target-side debugging stub. Tracing mode
4002 includes a new interaction mode in GDB and new commands: see the
4003 file tracepoint.c for more details.
4007 Configurations for embedded MIPS now include a simulator contributed
4008 by Cygnus Solutions. The simulator supports the instruction sets
4009 of most MIPS variants.
4013 Sparc configurations may now include the ERC32 simulator contributed
4014 by the European Space Agency. The simulator is not built into
4015 Sparc targets by default; configure with --enable-sim to include it.
4019 For target configurations that may include multiple variants of a
4020 basic architecture (such as MIPS and SH), you may now set the
4021 architecture explicitly. "set arch" sets, "info arch" lists
4022 the possible architectures.
4024 *** Changes in GDB-4.16:
4026 * New native configurations
4028 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4029 M68K NetBSD m68k-*-netbsd*
4030 PowerPC AIX 4.x powerpc-*-aix*
4031 PowerPC MacOS powerpc-*-macos*
4032 PowerPC Windows NT powerpcle-*-cygwin32
4033 RS/6000 AIX 4.x rs6000-*-aix4*
4037 ARM with RDP protocol arm-*-*
4038 I960 with MON960 i960-*-coff
4039 MIPS VxWorks mips*-*-vxworks*
4040 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4041 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4043 Matra Sparclet sparclet-*-*
4047 The powerpc-eabi configuration now includes the PSIM simulator,
4048 contributed by Andrew Cagney, with assistance from Mike Meissner.
4049 PSIM is a very elaborate model of the PowerPC, including not only
4050 basic instruction set execution, but also details of execution unit
4051 performance and I/O hardware. See sim/ppc/README for more details.
4055 GDB now works with Solaris 2.5.
4057 * Windows 95/NT native
4059 GDB will now work as a native debugger on Windows 95 and Windows NT.
4060 To build it from source, you must use the "gnu-win32" environment,
4061 which uses a DLL to emulate enough of Unix to run the GNU tools.
4062 Further information, binaries, and sources are available at
4063 ftp.cygnus.com, under pub/gnu-win32.
4065 * dont-repeat command
4067 If a user-defined command includes the command `dont-repeat', then the
4068 command will not be repeated if the user just types return. This is
4069 useful if the command is time-consuming to run, so that accidental
4070 extra keystrokes don't run the same command many times.
4072 * Send break instead of ^C
4074 The standard remote protocol now includes an option to send a break
4075 rather than a ^C to the target in order to interrupt it. By default,
4076 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4078 * Remote protocol timeout
4080 The standard remote protocol includes a new variable `remotetimeout'
4081 that allows you to set the number of seconds before GDB gives up trying
4082 to read from the target. The default value is 2.
4084 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4086 By default GDB will automatically keep track of objects as they are
4087 loaded and unloaded by the dynamic linker. By using the command `set
4088 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4089 when shared library events occur, thus allowing you to set breakpoints
4090 in shared libraries which are explicitly loaded by the inferior.
4092 Note this feature does not work on hpux8. On hpux9 you must link
4093 /usr/lib/end.o into your program. This feature should work
4094 automatically on hpux10.
4096 * Irix 5.x hardware watchpoint support
4098 Irix 5 configurations now support the use of hardware watchpoints.
4100 * Mips protocol "SYN garbage limit"
4102 When debugging a Mips target using the `target mips' protocol, you
4103 may set the number of characters that GDB will ignore by setting
4104 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4105 every character. The default value is 1050.
4107 * Recording and replaying remote debug sessions
4109 If you set `remotelogfile' to the name of a file, gdb will write to it
4110 a recording of a remote debug session. This recording may then be
4111 replayed back to gdb using "gdbreplay". See gdbserver/README for
4112 details. This is useful when you have a problem with GDB while doing
4113 remote debugging; you can make a recording of the session and send it
4114 to someone else, who can then recreate the problem.
4116 * Speedups for remote debugging
4118 GDB includes speedups for downloading and stepping MIPS systems using
4119 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4120 and more efficient S-record downloading.
4122 * Memory use reductions and statistics collection
4124 GDB now uses less memory and reports statistics about memory usage.
4125 Try the `maint print statistics' command, for example.
4127 *** Changes in GDB-4.15:
4129 * Psymtabs for XCOFF
4131 The symbol reader for AIX GDB now uses partial symbol tables. This
4132 can greatly improve startup time, especially for large executables.
4134 * Remote targets use caching
4136 Remote targets now use a data cache to speed up communication with the
4137 remote side. The data cache could lead to incorrect results because
4138 it doesn't know about volatile variables, thus making it impossible to
4139 debug targets which use memory mapped I/O devices. `set remotecache
4140 off' turns the the data cache off.
4142 * Remote targets may have threads
4144 The standard remote protocol now includes support for multiple threads
4145 in the target system, using new protocol commands 'H' and 'T'. See
4146 gdb/remote.c for details.
4150 If GDB is configured with `--enable-netrom', then it will include
4151 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4152 acts as though it is a bank of ROM on the target board, but you can
4153 write into it over the network. GDB's support consists only of
4154 support for fast loading into the emulated ROM; to debug, you must use
4155 another protocol, such as standard remote protocol. The usual
4156 sequence is something like
4158 target nrom <netrom-hostname>
4160 target remote <netrom-hostname>:1235
4164 GDB now includes support for the Apple Macintosh, as a host only. It
4165 may be run as either an MPW tool or as a standalone application, and
4166 it can debug through the serial port. All the usual GDB commands are
4167 available, but to the target command, you must supply "serial" as the
4168 device type instead of "/dev/ttyXX". See mpw-README in the main
4169 directory for more information on how to build. The MPW configuration
4170 scripts */mpw-config.in support only a few targets, and only the
4171 mips-idt-ecoff target has been tested.
4175 GDB configuration now uses autoconf. This is not user-visible,
4176 but does simplify configuration and building.
4180 GDB now supports hpux10.
4182 *** Changes in GDB-4.14:
4184 * New native configurations
4186 x86 FreeBSD i[345]86-*-freebsd
4187 x86 NetBSD i[345]86-*-netbsd
4188 NS32k NetBSD ns32k-*-netbsd
4189 Sparc NetBSD sparc-*-netbsd
4193 A29K VxWorks a29k-*-vxworks
4194 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4195 CPU32 EST-300 emulator m68*-*-est*
4196 PowerPC ELF powerpc-*-elf
4199 * Alpha OSF/1 support for procfs
4201 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4202 possible to attach to running processes. As the mounting of the /proc
4203 filesystem is optional on the Alpha, GDB automatically determines
4204 the availability of /proc during startup. This can lead to problems
4205 if /proc is unmounted after GDB has been started.
4207 * Arguments to user-defined commands
4209 User commands may accept up to 10 arguments separated by whitespace.
4210 Arguments are accessed within the user command via $arg0..$arg9. A
4213 print $arg0 + $arg1 + $arg2
4215 To execute the command use:
4218 Defines the command "adder" which prints the sum of its three arguments.
4219 Note the arguments are text substitutions, so they may reference variables,
4220 use complex expressions, or even perform inferior function calls.
4222 * New `if' and `while' commands
4224 This makes it possible to write more sophisticated user-defined
4225 commands. Both commands take a single argument, which is the
4226 expression to evaluate, and must be followed by the commands to
4227 execute, one per line, if the expression is nonzero, the list being
4228 terminated by the word `end'. The `if' command list may include an
4229 `else' word, which causes the following commands to be executed only
4230 if the expression is zero.
4232 * Fortran source language mode
4234 GDB now includes partial support for Fortran 77. It will recognize
4235 Fortran programs and can evaluate a subset of Fortran expressions, but
4236 variables and functions may not be handled correctly. GDB will work
4237 with G77, but does not yet know much about symbols emitted by other
4240 * Better HPUX support
4242 Most debugging facilities now work on dynamic executables for HPPAs
4243 running hpux9 or later. You can attach to running dynamically linked
4244 processes, but by default the dynamic libraries will be read-only, so
4245 for instance you won't be able to put breakpoints in them. To change
4246 that behavior do the following before running the program:
4252 This will cause the libraries to be mapped private and read-write.
4253 To revert to the normal behavior, do this:
4259 You cannot set breakpoints or examine data in the library until after
4260 the library is loaded if the function/data symbols do not have
4263 GDB can now also read debug symbols produced by the HP C compiler on
4264 HPPAs (sorry, no C++, Fortran or 68k support).
4266 * Target byte order now dynamically selectable
4268 You can choose which byte order to use with a target system, via the
4269 commands "set endian big" and "set endian little", and you can see the
4270 current setting by using "show endian". You can also give the command
4271 "set endian auto", in which case GDB will use the byte order
4272 associated with the executable. Currently, only embedded MIPS
4273 configurations support dynamic selection of target byte order.
4275 * New DOS host serial code
4277 This version uses DPMI interrupts to handle buffered I/O, so you
4278 no longer need to run asynctsr when debugging boards connected to
4281 *** Changes in GDB-4.13:
4283 * New "complete" command
4285 This lists all the possible completions for the rest of the line, if it
4286 were to be given as a command itself. This is intended for use by emacs.
4288 * Trailing space optional in prompt
4290 "set prompt" no longer adds a space for you after the prompt you set. This
4291 allows you to set a prompt which ends in a space or one that does not.
4293 * Breakpoint hit counts
4295 "info break" now displays a count of the number of times the breakpoint
4296 has been hit. This is especially useful in conjunction with "ignore"; you
4297 can ignore a large number of breakpoint hits, look at the breakpoint info
4298 to see how many times the breakpoint was hit, then run again, ignoring one
4299 less than that number, and this will get you quickly to the last hit of
4302 * Ability to stop printing at NULL character
4304 "set print null-stop" will cause GDB to stop printing the characters of
4305 an array when the first NULL is encountered. This is useful when large
4306 arrays actually contain only short strings.
4308 * Shared library breakpoints
4310 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4311 breakpoints in shared libraries before the executable is run.
4313 * Hardware watchpoints
4315 There is a new hardware breakpoint for the watch command for sparclite
4316 targets. See gdb/sparclite/hw_breakpoint.note.
4318 Hardware watchpoints are also now supported under GNU/Linux.
4322 Annotations have been added. These are for use with graphical interfaces,
4323 and are still experimental. Currently only gdba.el uses these.
4325 * Improved Irix 5 support
4327 GDB now works properly with Irix 5.2.
4329 * Improved HPPA support
4331 GDB now works properly with the latest GCC and GAS.
4333 * New native configurations
4335 Sequent PTX4 i[34]86-sequent-ptx4
4336 HPPA running OSF/1 hppa*-*-osf*
4337 Atari TT running SVR4 m68*-*-sysv4*
4338 RS/6000 LynxOS rs6000-*-lynxos*
4342 OS/9000 i[34]86-*-os9k
4343 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4346 * Hitachi SH7000 and E7000-PC ICE support
4348 There is now support for communicating with the Hitachi E7000-PC ICE.
4349 This is available automatically when GDB is configured for the SH.
4353 As usual, a variety of small fixes and improvements, both generic
4354 and configuration-specific. See the ChangeLog for more detail.
4356 *** Changes in GDB-4.12:
4358 * Irix 5 is now supported
4362 GDB-4.12 on the HPPA has a number of changes which make it unable
4363 to debug the output from the currently released versions of GCC and
4364 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4365 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4366 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4369 *** Changes in GDB-4.11:
4371 * User visible changes:
4375 The "set remotedebug" option is now consistent between the mips remote
4376 target, remote targets using the gdb-specific protocol, UDI (AMD's
4377 debug protocol for the 29k) and the 88k bug monitor. It is now an
4378 integer specifying a debug level (normally 0 or 1, but 2 means more
4379 debugging info for the mips target).
4381 * DEC Alpha native support
4383 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4384 debug info, but GDB works fairly well with the DEC compiler and should
4385 work with a future GCC release. See the README file for a few
4386 Alpha-specific notes.
4388 * Preliminary thread implementation
4390 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4392 * LynxOS native and target support for 386
4394 This release has been hosted on LynxOS 2.2, and also can be configured
4395 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4398 * Improvements in C++ mangling/demangling.
4400 This release has much better g++ debugging, specifically in name
4401 mangling/demangling, virtual function calls, print virtual table,
4402 call methods, ...etc.
4404 *** Changes in GDB-4.10:
4406 * User visible changes:
4408 Remote debugging using the GDB-specific (`target remote') protocol now
4409 supports the `load' command. This is only useful if you have some
4410 other way of getting the stub to the target system, and you can put it
4411 somewhere in memory where it won't get clobbered by the download.
4413 Filename completion now works.
4415 When run under emacs mode, the "info line" command now causes the
4416 arrow to point to the line specified. Also, "info line" prints
4417 addresses in symbolic form (as well as hex).
4419 All vxworks based targets now support a user settable option, called
4420 vxworks-timeout. This option represents the number of seconds gdb
4421 should wait for responses to rpc's. You might want to use this if
4422 your vxworks target is, perhaps, a slow software simulator or happens
4423 to be on the far side of a thin network line.
4427 This release contains support for using a DEC alpha as a GDB host for
4428 cross debugging. Native alpha debugging is not supported yet.
4431 *** Changes in GDB-4.9:
4435 This is the first GDB release which is accompanied by a matching testsuite.
4436 The testsuite requires installation of dejagnu, which should be available
4437 via ftp from most sites that carry GNU software.
4441 'Cfront' style demangling has had its name changed to 'ARM' style, to
4442 emphasize that it was written from the specifications in the C++ Annotated
4443 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4444 disclaimers, it still generated too much confusion with users attempting to
4445 use gdb with AT&T cfront.
4449 GDB now uses a standard remote interface to a simulator library.
4450 So far, the library contains simulators for the Zilog Z8001/2, the
4451 Hitachi H8/300, H8/500 and Super-H.
4453 * New targets supported
4455 H8/300 simulator h8300-hitachi-hms or h8300hms
4456 H8/500 simulator h8500-hitachi-hms or h8500hms
4457 SH simulator sh-hitachi-hms or sh
4458 Z8000 simulator z8k-zilog-none or z8ksim
4459 IDT MIPS board over serial line mips-idt-ecoff
4461 Cross-debugging to GO32 targets is supported. It requires a custom
4462 version of the i386-stub.c module which is integrated with the
4463 GO32 memory extender.
4465 * New remote protocols
4467 MIPS remote debugging protocol.
4469 * New source languages supported
4471 This version includes preliminary support for Chill, a Pascal like language
4472 used by telecommunications companies. Chill support is also being integrated
4473 into the GNU compiler, but we don't know when it will be publically available.
4476 *** Changes in GDB-4.8:
4478 * HP Precision Architecture supported
4480 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4481 version of this support was available as a set of patches from the
4482 University of Utah. GDB does not support debugging of programs
4483 compiled with the HP compiler, because HP will not document their file
4484 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4485 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4487 Many problems in the preliminary version have been fixed.
4489 * Faster and better demangling
4491 We have improved template demangling and fixed numerous bugs in the GNU style
4492 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4493 character types (wchar_t) are now supported. Demangling of each symbol is now
4494 only done once, and is cached when the symbol table for a file is read in.
4495 This results in a small increase in memory usage for C programs, a moderate
4496 increase in memory usage for C++ programs, and a fantastic speedup in
4499 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4500 from the specifications in the Annotated Reference Manual, which AT&T's
4501 compiler does not actually implement.
4503 * G++ multiple inheritance compiler problem
4505 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4506 inheritance lattices was reworked to properly discover ambiguities. We
4507 recently found an example which causes this new algorithm to fail in a
4508 very subtle way, producing bad debug information for those classes.
4509 The file 'gcc.patch' (in this directory) can be applied to gcc to
4510 circumvent the problem. A future GCC release will contain a complete
4513 The previous G++ debug info problem (mentioned below for the gdb-4.7
4514 release) is fixed in gcc version 2.3.2.
4516 * Improved configure script
4518 The `configure' script will now attempt to guess your system type if
4519 you don't supply a host system type. The old scheme of supplying a
4520 host system triplet is preferable over using this. All the magic is
4521 done in the new `config.guess' script. Examine it for details.
4523 We have also brought our configure script much more in line with the FSF's
4524 version. It now supports the --with-xxx options. In particular,
4525 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4526 The resulting GDB will not be able to read arbitrary object file formats --
4527 only the format ``expected'' to be used on the configured target system.
4528 We hope to make this the default in a future release.
4530 * Documentation improvements
4532 There's new internal documentation on how to modify GDB, and how to
4533 produce clean changes to the code. We implore people to read it
4534 before submitting changes.
4536 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4537 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4538 `info' files are also provided. To build `info' files from scratch,
4539 you will need the latest `makeinfo' release, which will be available in
4540 a future texinfo-X.Y release.
4542 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4543 We're not sure exactly which versions have this problem, but it has
4544 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4545 or better. If that isn't possible, there is a patch in
4546 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4547 around this problem.
4551 GDB now supports array constants that can be used in expressions typed in by
4552 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4553 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4556 The new directory `gdb/sparclite' contains a program that demonstrates
4557 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4559 * New native hosts supported
4561 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4562 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4564 * New targets supported
4566 AMD 29k family via UDI a29k-amd-udi or udi29k
4568 * New file formats supported
4570 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4571 HPUX core files, and SCO 3.2v2 core files.
4575 Attaching to processes now works again; thanks for the many bug reports.
4577 We have also stomped on a bunch of core dumps caused by
4578 printf_filtered("%s") problems.
4580 We eliminated a copyright problem on the rpc and ptrace header files
4581 for VxWorks, which was discovered at the last minute during the 4.7
4582 release. You should now be able to build a VxWorks GDB.
4584 You can now interrupt gdb while an attached process is running. This
4585 will cause the attached process to stop, and give control back to GDB.
4587 We fixed problems caused by using too many file descriptors
4588 for reading symbols from object files and libraries. This was
4589 especially a problem for programs that used many (~100) shared
4592 The `step' command now only enters a subroutine if there is line number
4593 information for the subroutine. Otherwise it acts like the `next'
4594 command. Previously, `step' would enter subroutines if there was
4595 any debugging information about the routine. This avoids problems
4596 when using `cc -g1' on MIPS machines.
4598 * Internal improvements
4600 GDB's internal interfaces have been improved to make it easier to support
4601 debugging of multiple languages in the future.
4603 GDB now uses a common structure for symbol information internally.
4604 Minimal symbols (derived from linkage symbols in object files), partial
4605 symbols (from a quick scan of debug information), and full symbols
4606 contain a common subset of information, making it easier to write
4607 shared code that handles any of them.
4609 * New command line options
4611 We now accept --silent as an alias for --quiet.
4615 The memory-mapped-malloc library is now licensed under the GNU Library
4616 General Public License.
4618 *** Changes in GDB-4.7:
4620 * Host/native/target split
4622 GDB has had some major internal surgery to untangle the support for
4623 hosts and remote targets. Now, when you configure GDB for a remote
4624 target, it will no longer load in all of the support for debugging
4625 local programs on the host. When fully completed and tested, this will
4626 ensure that arbitrary host/target combinations are possible.
4628 The primary conceptual shift is to separate the non-portable code in
4629 GDB into three categories. Host specific code is required any time GDB
4630 is compiled on that host, regardless of the target. Target specific
4631 code relates to the peculiarities of the target, but can be compiled on
4632 any host. Native specific code is everything else: it can only be
4633 built when the host and target are the same system. Child process
4634 handling and core file support are two common `native' examples.
4636 GDB's use of /proc for controlling Unix child processes is now cleaner.
4637 It has been split out into a single module under the `target_ops' vector,
4638 plus two native-dependent functions for each system that uses /proc.
4640 * New hosts supported
4642 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4643 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4644 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4646 * New targets supported
4648 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4649 68030 and CPU32 m68030-*-*, m68332-*-*
4651 * New native hosts supported
4653 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4654 (386bsd is not well tested yet)
4655 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4657 * New file formats supported
4659 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4660 supports reading of `a.out.adobe' object files, which are an a.out
4661 format extended with minimal information about multiple sections.
4665 `show copying' is the same as the old `info copying'.
4666 `show warranty' is the same as `info warrantee'.
4667 These were renamed for consistency. The old commands continue to work.
4669 `info handle' is a new alias for `info signals'.
4671 You can now define pre-command hooks, which attach arbitrary command
4672 scripts to any command. The commands in the hook will be executed
4673 prior to the user's command. You can also create a hook which will be
4674 executed whenever the program stops. See gdb.texinfo.
4678 We now deal with Cfront style name mangling, and can even extract type
4679 info from mangled symbols. GDB can automatically figure out which
4680 symbol mangling style your C++ compiler uses.
4682 Calling of methods and virtual functions has been improved as well.
4686 The crash that occured when debugging Sun Ansi-C compiled binaries is
4687 fixed. This was due to mishandling of the extra N_SO stabs output
4690 We also finally got Ultrix 4.2 running in house, and fixed core file
4691 support, with help from a dozen people on the net.
4693 John M. Farrell discovered that the reason that single-stepping was so
4694 slow on all of the Mips based platforms (primarily SGI and DEC) was
4695 that we were trying to demangle and lookup a symbol used for internal
4696 purposes on every instruction that was being stepped through. Changing
4697 the name of that symbol so that it couldn't be mistaken for a C++
4698 mangled symbol sped things up a great deal.
4700 Rich Pixley sped up symbol lookups in general by getting much smarter
4701 about when C++ symbol mangling is necessary. This should make symbol
4702 completion (TAB on the command line) much faster. It's not as fast as
4703 we'd like, but it's significantly faster than gdb-4.6.
4707 A new user controllable variable 'call_scratch_address' can
4708 specify the location of a scratch area to be used when GDB
4709 calls a function in the target. This is necessary because the
4710 usual method of putting the scratch area on the stack does not work
4711 in systems that have separate instruction and data spaces.
4713 We integrated changes to support the 29k UDI (Universal Debugger
4714 Interface), but discovered at the last minute that we didn't have all
4715 of the appropriate copyright paperwork. We are working with AMD to
4716 resolve this, and hope to have it available soon.
4720 We have sped up the remote serial line protocol, especially for targets
4721 with lots of registers. It now supports a new `expedited status' ('T')
4722 message which can be used in place of the existing 'S' status message.
4723 This allows the remote stub to send only the registers that GDB
4724 needs to make a quick decision about single-stepping or conditional
4725 breakpoints, eliminating the need to fetch the entire register set for
4726 each instruction being stepped through.
4728 The GDB remote serial protocol now implements a write-through cache for
4729 registers, only re-reading the registers if the target has run.
4731 There is also a new remote serial stub for SPARC processors. You can
4732 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4733 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4734 processor with a serial port.
4738 Configure.in files have become much easier to read and modify. A new
4739 `table driven' format makes it more obvious what configurations are
4740 supported, and what files each one uses.
4744 There is a new opcodes library which will eventually contain all of the
4745 disassembly routines and opcode tables. At present, it only contains
4746 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4747 disassembler (binutils/objdump) to share these routines.
4749 The libiberty library is now copylefted under the GNU Library General
4750 Public License. This allows more liberal use, and was done so libg++
4751 can use it. This makes no difference to GDB, since the Library License
4752 grants all the rights from the General Public License.
4756 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4757 reference to the stabs symbol info used by the debugger. It is (as far
4758 as we know) the only published document on this fascinating topic. We
4759 encourage you to read it, compare it to the stabs information on your
4760 system, and send improvements on the document in general (to
4761 bug-gdb@prep.ai.mit.edu).
4763 And, of course, many bugs have been fixed.
4766 *** Changes in GDB-4.6:
4768 * Better support for C++ function names
4770 GDB now accepts as input the "demangled form" of C++ overloaded function
4771 names and member function names, and can do command completion on such names
4772 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4773 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4774 Make use of command completion, it is your friend.
4776 GDB also now accepts a variety of C++ mangled symbol formats. They are
4777 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4778 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4779 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4780 for the list of formats.
4782 * G++ symbol mangling problem
4784 Recent versions of gcc have a bug in how they emit debugging information for
4785 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4786 directory) can be applied to gcc to fix the problem. Alternatively, if you
4787 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4788 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4789 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4792 * New 'maintenance' command
4794 All of the commands related to hacking GDB internals have been moved out of
4795 the main command set, and now live behind the 'maintenance' command. This
4796 can also be abbreviated as 'mt'. The following changes were made:
4798 dump-me -> maintenance dump-me
4799 info all-breakpoints -> maintenance info breakpoints
4800 printmsyms -> maintenance print msyms
4801 printobjfiles -> maintenance print objfiles
4802 printpsyms -> maintenance print psymbols
4803 printsyms -> maintenance print symbols
4805 The following commands are new:
4807 maintenance demangle Call internal GDB demangler routine to
4808 demangle a C++ link name and prints the result.
4809 maintenance print type Print a type chain for a given symbol
4811 * Change to .gdbinit file processing
4813 We now read the $HOME/.gdbinit file before processing the argv arguments
4814 (e.g. reading symbol files or core files). This allows global parameters to
4815 be set, which will apply during the symbol reading. The ./.gdbinit is still
4816 read after argv processing.
4818 * New hosts supported
4820 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4822 GNU/Linux support i386-unknown-linux or linux
4824 We are also including code to support the HP/PA running BSD and HPUX. This
4825 is almost guaranteed not to work, as we didn't have time to test or build it
4826 for this release. We are including it so that the more adventurous (or
4827 masochistic) of you can play with it. We also had major problems with the
4828 fact that the compiler that we got from HP doesn't support the -g option.
4831 * New targets supported
4833 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4835 * More smarts about finding #include files
4837 GDB now remembers the compilation directory for all include files, and for
4838 all files from which C is generated (like yacc and lex sources). This
4839 greatly improves GDB's ability to find yacc/lex sources, and include files,
4840 especially if you are debugging your program from a directory different from
4841 the one that contains your sources.
4843 We also fixed a bug which caused difficulty with listing and setting
4844 breakpoints in include files which contain C code. (In the past, you had to
4845 try twice in order to list an include file that you hadn't looked at before.)
4847 * Interesting infernals change
4849 GDB now deals with arbitrary numbers of sections, where the symbols for each
4850 section must be relocated relative to that section's landing place in the
4851 target's address space. This work was needed to support ELF with embedded
4852 stabs used by Solaris-2.0.
4854 * Bug fixes (of course!)
4856 There have been loads of fixes for the following things:
4857 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4858 i960, stabs, DOS(GO32), procfs, etc...
4860 See the ChangeLog for details.
4862 *** Changes in GDB-4.5:
4864 * New machines supported (host and target)
4866 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4868 SGI Irix-4.x mips-sgi-irix4 or iris4
4870 * New malloc package
4872 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4873 Mmalloc is capable of handling mutiple heaps of memory. It is also
4874 capable of saving a heap to a file, and then mapping it back in later.
4875 This can be used to greatly speedup the startup of GDB by using a
4876 pre-parsed symbol table which lives in a mmalloc managed heap. For
4877 more details, please read mmalloc/mmalloc.texi.
4881 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4882 'help info proc' for details.
4884 * MIPS ecoff symbol table format
4886 The code that reads MIPS symbol table format is now supported on all hosts.
4887 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4890 * File name changes for MS-DOS
4892 Many files in the config directories have been renamed to make it easier to
4893 support GDB on MS-DOSe systems (which have very restrictive file name
4894 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4895 environment) is close to working but has some remaining problems. Note
4896 that debugging of DOS programs is not supported, due to limitations
4897 in the ``operating system'', but it can be used to host cross-debugging.
4899 * Cross byte order fixes
4901 Many fixes have been made to support cross debugging of Sparc and MIPS
4902 targets from hosts whose byte order differs.
4904 * New -mapped and -readnow options
4906 If memory-mapped files are available on your system through the 'mmap'
4907 system call, you can use the -mapped option on the `file' or
4908 `symbol-file' commands to cause GDB to write the symbols from your
4909 program into a reusable file. If the program you are debugging is
4910 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4911 Future GDB debugging sessions will notice the presence of this file,
4912 and will quickly map in symbol information from it, rather than reading
4913 the symbol table from the executable program. Using the '-mapped'
4914 option in a GDB `file' or `symbol-file' command has the same effect as
4915 starting GDB with the '-mapped' command-line option.
4917 You can cause GDB to read the entire symbol table immediately by using
4918 the '-readnow' option with any of the commands that load symbol table
4919 information (or on the GDB command line). This makes the command
4920 slower, but makes future operations faster.
4922 The -mapped and -readnow options are typically combined in order to
4923 build a `fred.syms' file that contains complete symbol information.
4924 A simple GDB invocation to do nothing but build a `.syms' file for future
4927 gdb -batch -nx -mapped -readnow programname
4929 The `.syms' file is specific to the host machine on which GDB is run.
4930 It holds an exact image of GDB's internal symbol table. It cannot be
4931 shared across multiple host platforms.
4933 * longjmp() handling
4935 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4936 siglongjmp() without losing control. This feature has not yet been ported to
4937 all systems. It currently works on many 386 platforms, all MIPS-based
4938 platforms (SGI, DECstation, etc), and Sun3/4.
4942 Preliminary work has been put in to support the new Solaris OS from Sun. At
4943 this time, it can control and debug processes, but it is not capable of
4948 As always, many many bug fixes. The major areas were with g++, and mipsread.
4949 People using the MIPS-based platforms should experience fewer mysterious
4950 crashes and trashed symbol tables.
4952 *** Changes in GDB-4.4:
4954 * New machines supported (host and target)
4956 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4958 BSD Reno on Vax vax-dec-bsd
4959 Ultrix on Vax vax-dec-ultrix
4961 * New machines supported (target)
4963 AMD 29000 embedded, using EBMON a29k-none-none
4967 GDB continues to improve its handling of C++. `References' work better.
4968 The demangler has also been improved, and now deals with symbols mangled as
4969 per the Annotated C++ Reference Guide.
4971 GDB also now handles `stabs' symbol information embedded in MIPS
4972 `ecoff' symbol tables. Since the ecoff format was not easily
4973 extensible to handle new languages such as C++, this appeared to be a
4974 good way to put C++ debugging info into MIPS binaries. This option
4975 will be supported in the GNU C compiler, version 2, when it is
4978 * New features for SVR4
4980 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4981 shared libraries. Debugging dynamically linked programs should present
4982 only minor differences from debugging statically linked programs.
4984 The `info proc' command will print out information about any process
4985 on an SVR4 system (including the one you are debugging). At the moment,
4986 it prints the address mappings of the process.
4988 If you bring up GDB on another SVR4 system, please send mail to
4989 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4991 * Better dynamic linking support in SunOS
4993 Reading symbols from shared libraries which contain debugging symbols
4994 now works properly. However, there remain issues such as automatic
4995 skipping of `transfer vector' code during function calls, which
4996 make it harder to debug code in a shared library, than to debug the
4997 same code linked statically.
5001 GDB is now using the latest `getopt' routines from the FSF. This
5002 version accepts the -- prefix for options with long names. GDB will
5003 continue to accept the old forms (-option and +option) as well.
5004 Various single letter abbreviations for options have been explicity
5005 added to the option table so that they won't get overshadowed in the
5006 future by other options that begin with the same letter.
5010 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5011 Many assorted bugs have been handled. Many more remain to be handled.
5012 See the various ChangeLog files (primarily in gdb and bfd) for details.
5015 *** Changes in GDB-4.3:
5017 * New machines supported (host and target)
5019 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5020 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5021 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5023 * Almost SCO Unix support
5025 We had hoped to support:
5026 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5027 (except for core file support), but we discovered very late in the release
5028 that it has problems with process groups that render gdb unusable. Sorry
5029 about that. I encourage people to fix it and post the fixes.
5031 * Preliminary ELF and DWARF support
5033 GDB can read ELF object files on System V Release 4, and can handle
5034 debugging records for C, in DWARF format, in ELF files. This support
5035 is preliminary. If you bring up GDB on another SVR4 system, please
5036 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5041 GDB now uses the latest `readline' library. One user-visible change
5042 is that two tabs will list possible command completions, which previously
5043 required typing M-? (meta-question mark, or ESC ?).
5047 The `stepi' bug that many of you noticed has been squashed.
5048 Many bugs in C++ have been handled. Many more remain to be handled.
5049 See the various ChangeLog files (primarily in gdb and bfd) for details.
5051 * State of the MIPS world (in case you wondered):
5053 GDB can understand the symbol tables emitted by the compilers
5054 supplied by most vendors of MIPS-based machines, including DEC. These
5055 symbol tables are in a format that essentially nobody else uses.
5057 Some versions of gcc come with an assembler post-processor called
5058 mips-tfile. This program is required if you want to do source-level
5059 debugging of gcc-compiled programs. I believe FSF does not ship
5060 mips-tfile with gcc version 1, but it will eventually come with gcc
5063 Debugging of g++ output remains a problem. g++ version 1.xx does not
5064 really support it at all. (If you're lucky, you should be able to get
5065 line numbers and stack traces to work, but no parameters or local
5066 variables.) With some work it should be possible to improve the
5069 When gcc version 2 is released, you will have somewhat better luck.
5070 However, even then you will get confusing results for inheritance and
5073 We will eventually provide full debugging of g++ output on
5074 DECstations. This will probably involve some kind of stabs-in-ecoff
5075 encapulation, but the details have not been worked out yet.
5078 *** Changes in GDB-4.2:
5080 * Improved configuration
5082 Only one copy of `configure' exists now, and it is not self-modifying.
5083 Porting BFD is simpler.
5087 The `step' and `next' commands now only stop at the first instruction
5088 of a source line. This prevents the multiple stops that used to occur
5089 in switch statements, for-loops, etc. `Step' continues to stop if a
5090 function that has debugging information is called within the line.
5094 Lots of small bugs fixed. More remain.
5096 * New host supported (not target)
5098 Intel 386 PC clone running Mach i386-none-mach
5101 *** Changes in GDB-4.1:
5103 * Multiple source language support
5105 GDB now has internal scaffolding to handle several source languages.
5106 It determines the type of each source file from its filename extension,
5107 and will switch expression parsing and number formatting to match the
5108 language of the function in the currently selected stack frame.
5109 You can also specifically set the language to be used, with
5110 `set language c' or `set language modula-2'.
5114 GDB now has preliminary support for the GNU Modula-2 compiler,
5115 currently under development at the State University of New York at
5116 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5117 continue through the fall of 1991 and into 1992.
5119 Other Modula-2 compilers are currently not supported, and attempting to
5120 debug programs compiled with them will likely result in an error as the
5121 symbol table is read. Feel free to work on it, though!
5123 There are hooks in GDB for strict type checking and range checking,
5124 in the `Modula-2 philosophy', but they do not currently work.
5128 GDB can now write to executable and core files (e.g. patch
5129 a variable's value). You must turn this switch on, specify
5130 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5131 by assigning a new value to a variable. Modifications take
5134 * Automatic SunOS shared library reading
5136 When you run your program, GDB automatically determines where its
5137 shared libraries (if any) have been loaded, and reads their symbols.
5138 The `share' command is no longer needed. This also works when
5139 examining core files.
5143 You can specify the number of lines that the `list' command shows.
5146 * New machines supported (host and target)
5148 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5149 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5150 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5152 * New hosts supported (not targets)
5154 IBM RT/PC: romp-ibm-aix or rtpc
5156 * New targets supported (not hosts)
5158 AMD 29000 embedded with COFF a29k-none-coff
5159 AMD 29000 embedded with a.out a29k-none-aout
5160 Ultracomputer remote kernel debug a29k-nyu-kern
5162 * New remote interfaces
5168 *** Changes in GDB-4.0:
5172 Wide output is wrapped at good places to make the output more readable.
5174 Gdb now supports cross-debugging from a host machine of one type to a
5175 target machine of another type. Communication with the target system
5176 is over serial lines. The ``target'' command handles connecting to the
5177 remote system; the ``load'' command will download a program into the
5178 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5179 also supports debugging of realtime processes running under VxWorks,
5180 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5181 stub on the target system.
5183 New CPUs supported include the AMD 29000 and Intel 960.
5185 GDB now reads object files and symbol tables via a ``binary file''
5186 library, which allows a single copy of GDB to debug programs of multiple
5187 object file types such as a.out and coff.
5189 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5190 refcard.dvi and refcard.ps are available to format it).
5193 * Control-Variable user interface simplified
5195 All variables that control the operation of the debugger can be set
5196 by the ``set'' command, and displayed by the ``show'' command.
5198 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5199 ``Show prompt'' produces the response:
5200 Gdb's prompt is new-gdb=>.
5202 What follows are the NEW set commands. The command ``help set'' will
5203 print a complete list of old and new set commands. ``help set FOO''
5204 will give a longer description of the variable FOO. ``show'' will show
5205 all of the variable descriptions and their current settings.
5207 confirm on/off: Enables warning questions for operations that are
5208 hard to recover from, e.g. rerunning the program while
5209 it is already running. Default is ON.
5211 editing on/off: Enables EMACS style command line editing
5212 of input. Previous lines can be recalled with
5213 control-P, the current line can be edited with control-B,
5214 you can search for commands with control-R, etc.
5217 history filename NAME: NAME is where the gdb command history
5218 will be stored. The default is .gdb_history,
5219 or the value of the environment variable
5222 history size N: The size, in commands, of the command history. The
5223 default is 256, or the value of the environment variable
5226 history save on/off: If this value is set to ON, the history file will
5227 be saved after exiting gdb. If set to OFF, the
5228 file will not be saved. The default is OFF.
5230 history expansion on/off: If this value is set to ON, then csh-like
5231 history expansion will be performed on
5232 command line input. The default is OFF.
5234 radix N: Sets the default radix for input and output. It can be set
5235 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5236 in the current radix, so "set radix 10" is always a no-op.
5238 height N: This integer value is the number of lines on a page. Default
5239 is 24, the current `stty rows'' setting, or the ``li#''
5240 setting from the termcap entry matching the environment
5243 width N: This integer value is the number of characters on a line.
5244 Default is 80, the current `stty cols'' setting, or the ``co#''
5245 setting from the termcap entry matching the environment
5248 Note: ``set screensize'' is obsolete. Use ``set height'' and
5249 ``set width'' instead.
5251 print address on/off: Print memory addresses in various command displays,
5252 such as stack traces and structure values. Gdb looks
5253 more ``symbolic'' if you turn this off; it looks more
5254 ``machine level'' with it on. Default is ON.
5256 print array on/off: Prettyprint arrays. New convenient format! Default
5259 print demangle on/off: Print C++ symbols in "source" form if on,
5262 print asm-demangle on/off: Same, for assembler level printouts
5265 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5268 * Support for Epoch Environment.
5270 The epoch environment is a version of Emacs v18 with windowing. One
5271 new command, ``inspect'', is identical to ``print'', except that if you
5272 are running in the epoch environment, the value is printed in its own
5276 * Support for Shared Libraries
5278 GDB can now debug programs and core files that use SunOS shared libraries.
5279 Symbols from a shared library cannot be referenced
5280 before the shared library has been linked with the program (this
5281 happens after you type ``run'' and before the function main() is entered).
5282 At any time after this linking (including when examining core files
5283 from dynamically linked programs), gdb reads the symbols from each
5284 shared library when you type the ``sharedlibrary'' command.
5285 It can be abbreviated ``share''.
5287 sharedlibrary REGEXP: Load shared object library symbols for files
5288 matching a unix regular expression. No argument
5289 indicates to load symbols for all shared libraries.
5291 info sharedlibrary: Status of loaded shared libraries.
5296 A watchpoint stops execution of a program whenever the value of an
5297 expression changes. Checking for this slows down execution
5298 tremendously whenever you are in the scope of the expression, but is
5299 quite useful for catching tough ``bit-spreader'' or pointer misuse
5300 problems. Some machines such as the 386 have hardware for doing this
5301 more quickly, and future versions of gdb will use this hardware.
5303 watch EXP: Set a watchpoint (breakpoint) for an expression.
5305 info watchpoints: Information about your watchpoints.
5307 delete N: Deletes watchpoint number N (same as breakpoints).
5308 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5309 enable N: Re-enables watchpoint number N (same as breakpoints).
5312 * C++ multiple inheritance
5314 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5317 * C++ exception handling
5319 Gdb now supports limited C++ exception handling. Besides the existing
5320 ability to breakpoint on an exception handler, gdb can breakpoint on
5321 the raising of an exception (before the stack is peeled back to the
5324 catch FOO: If there is a FOO exception handler in the dynamic scope,
5325 set a breakpoint to catch exceptions which may be raised there.
5326 Multiple exceptions (``catch foo bar baz'') may be caught.
5328 info catch: Lists all exceptions which may be caught in the
5329 current stack frame.
5332 * Minor command changes
5334 The command ``call func (arg, arg, ...)'' now acts like the print
5335 command, except it does not print or save a value if the function's result
5336 is void. This is similar to dbx usage.
5338 The ``up'' and ``down'' commands now always print the frame they end up
5339 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5340 frames without printing.
5342 * New directory command
5344 'dir' now adds directories to the FRONT of the source search path.
5345 The path starts off empty. Source files that contain debug information
5346 about the directory in which they were compiled can be found even
5347 with an empty path; Sun CC and GCC include this information. If GDB can't
5348 find your source file in the current directory, type "dir .".
5350 * Configuring GDB for compilation
5352 For normal use, type ``./configure host''. See README or gdb.texinfo
5355 GDB now handles cross debugging. If you are remotely debugging between
5356 two different machines, type ``./configure host -target=targ''.
5357 Host is the machine where GDB will run; targ is the machine
5358 where the program that you are debugging will run.