1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
8 ** Frame filters and frame decorators have been added.
12 Nios II ELF nios2*-*-elf
13 Nios II GNU/Linux nios2*-*-linux
14 Texas Instruments MSP430 msp430*-*-elf
18 Like "catch throw", but catches a re-thrown exception.
20 Renamed from old "maint check-symtabs".
22 Perform consistency checks on symtabs.
24 Expand symtabs matching an optional regexp.
27 Display the details of GDB configure-time options.
29 maint set|show per-command
30 maint set|show per-command space
31 maint set|show per-command time
32 maint set|show per-command symtab
33 Enable display of per-command gdb resource usage.
37 set print raw frame-arguments
38 show print raw frame-arguments
39 Set/show whether to print frame arguments in raw mode,
40 disregarding any defined pretty-printers.
42 set remote trace-status-packet
43 show remote trace-status-packet
44 Set/show the use of remote protocol qTStatus packet.
48 Control display of debugging messages related to Nios II targets.
52 Control whether target-assisted range stepping is enabled.
54 * You can now use a literal value 'unlimited' for options that
55 interpret 0 or -1 as meaning "unlimited". E.g., "set
56 trace-buffer-size unlimited" is now an alias for "set
57 trace-buffer-size -1" and "set height unlimited" is now an alias for
60 * New command-line options
62 Display the details of GDB configure-time options.
64 * The command 'tsave' can now support new option '-ctf' to save trace
65 buffer in Common Trace Format.
67 * Newly installed $prefix/bin/gcore acts as a shell interface for the
70 * GDB now implements the the C++ 'typeid' operator.
72 * The new convenience variable $_exception holds the exception being
73 thrown or caught at an exception-related catchpoint.
75 * The exception-related catchpoints, like "catch throw", now accept a
76 regular expression which can be used to filter exceptions by type.
80 ** The -trace-save MI command can optionally save trace buffer in Common
83 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
85 ** The command -data-list-register-values now accepts an optional
86 "--skip-unavailable" option. When used, only the available registers
89 ** The new command -trace-frame-collected dumps collected variables,
90 computed expressions, tvars, memory and registers in a traceframe.
92 * New system-wide configuration scripts
93 A GDB installation now provides scripts suitable for use as system-wide
94 configuration scripts for the following systems:
98 * GDB now supports target-assigned range stepping with remote targets.
99 This improves the performance of stepping source lines by reducing
100 the number of control packets from/to GDB. See "New remote packets"
103 * GDB now understands the element 'tvar' in the XML traceframe info.
104 It has the id of the collected trace state variables.
110 The vCont packet supports a new 'r' action, that tells the remote
111 stub to step through an address range itself, without GDB
112 involvemement at each single-step.
114 qXfer:libraries-svr4:read's annex
115 The previously unused annex of the qXfer:libraries-svr4:read packet
116 is now used to support passing an argument list. The remote stub
117 reports support for this argument list to GDB's qSupported query.
118 The defined arguments are "start" and "prev", used to reduce work
119 necessary for library list updating, resulting in significant
122 * New features in the GDB remote stub, GDBserver
124 ** GDBserver now supports target-assisted range stepping. Currently
125 enabled on x86/x86_64 GNU/Linux targets.
127 ** GDBserver now adds element 'tvar' in the XML in the reply to
128 'qXfer:traceframe-info:read'. It has the id of the collected
129 trace state variables.
131 * New 'z' formatter for printing and examining memory, this displays the
132 value as hexadecimal zero padded on the left to the size of the type.
134 *** Changes in GDB 7.6
136 * Target record has been renamed to record-full.
137 Record/replay is now enabled with the "record full" command.
138 This also affects settings that are associated with full record/replay
139 that have been moved from "set/show record" to "set/show record full":
141 set|show record full insn-number-max
142 set|show record full stop-at-limit
143 set|show record full memory-query
145 * A new record target "record-btrace" has been added. The new target
146 uses hardware support to record the control-flow of a process. It
147 does not support replaying the execution, but it implements the
148 below new commands for investigating the recorded execution log.
149 This new recording method can be enabled using:
153 The "record-btrace" target is only available on Intel Atom processors
154 and requires a Linux kernel 2.6.32 or later.
156 * Two new commands have been added for record/replay to give information
157 about the recorded execution without having to replay the execution.
158 The commands are only supported by "record btrace".
160 record instruction-history prints the execution history at
161 instruction granularity
163 record function-call-history prints the execution history at
166 * New native configurations
168 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
169 FreeBSD/powerpc powerpc*-*-freebsd
170 x86_64/Cygwin x86_64-*-cygwin*
171 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
175 ARM AArch64 aarch64*-*-elf
176 ARM AArch64 GNU/Linux aarch64*-*-linux
177 Lynx 178 PowerPC powerpc-*-lynx*178
178 x86_64/Cygwin x86_64-*-cygwin*
179 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
181 * If the configured location of system.gdbinit file (as given by the
182 --with-system-gdbinit option at configure time) is in the
183 data-directory (as specified by --with-gdb-datadir at configure
184 time) or in one of its subdirectories, then GDB will look for the
185 system-wide init file in the directory specified by the
186 --data-directory command-line option.
188 * New command line options:
190 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
191 other initialization files, unlike -nx which disables all of them.
193 * Removed command line options
195 -epoch This was used by the gdb mode in Epoch, an ancient fork of
198 * The 'ptype' and 'whatis' commands now accept an argument to control
201 * 'info proc' now works on some core files.
205 ** Vectors can be created with gdb.Type.vector.
207 ** Python's atexit.register now works in GDB.
209 ** Types can be pretty-printed via a Python API.
211 ** Python 3 is now supported (in addition to Python 2.4 or later)
213 ** New class gdb.Architecture exposes GDB's internal representation
214 of architecture in the Python API.
216 ** New method Frame.architecture returns the gdb.Architecture object
217 corresponding to the frame's architecture.
219 * New Python-based convenience functions:
221 ** $_memeq(buf1, buf2, length)
222 ** $_streq(str1, str2)
224 ** $_regex(str, regex)
226 * The 'cd' command now defaults to using '~' (the home directory) if not
229 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
230 default for GCC since November 2000.
232 * The command 'forward-search' can now be abbreviated as 'fo'.
234 * The command 'info tracepoints' can now display 'installed on target'
235 or 'not installed on target' for each non-pending location of tracepoint.
237 * New configure options
239 --enable-libmcheck/--disable-libmcheck
240 By default, development versions are built with -lmcheck on hosts
241 that support it, in order to help track memory corruption issues.
242 Release versions, on the other hand, are built without -lmcheck
243 by default. The --enable-libmcheck/--disable-libmcheck configure
244 options allow the user to override that default.
245 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
246 This configure option allows the user to build GDB with
247 libbabeltrace using which GDB can read Common Trace Format data.
249 * New commands (for set/show, see "New options" below)
252 Catch signals. This is similar to "handle", but allows commands and
253 conditions to be attached.
256 List the BFDs known to GDB.
258 python-interactive [command]
260 Start a Python interactive prompt, or evaluate the optional command
261 and print the result of expressions.
264 "py" is a new alias for "python".
266 enable type-printer [name]...
267 disable type-printer [name]...
268 Enable or disable type printers.
272 ** For the Renesas Super-H architecture, the "regs" command has been removed
273 (has been deprecated in GDB 7.5), and "info all-registers" should be used
278 set print type methods (on|off)
279 show print type methods
280 Control whether method declarations are displayed by "ptype".
281 The default is to show them.
283 set print type typedefs (on|off)
284 show print type typedefs
285 Control whether typedef definitions are displayed by "ptype".
286 The default is to show them.
288 set filename-display basename|relative|absolute
289 show filename-display
290 Control the way in which filenames is displayed.
291 The default is "relative", which preserves previous behavior.
293 set trace-buffer-size
294 show trace-buffer-size
295 Request target to change the size of trace buffer.
297 set remote trace-buffer-size-packet auto|on|off
298 show remote trace-buffer-size-packet
299 Control the use of the remote protocol `QTBuffer:size' packet.
303 Control display of debugging messages related to ARM AArch64.
306 set debug coff-pe-read
307 show debug coff-pe-read
308 Control display of debugging messages related to reading of COFF/PE
313 Control display of debugging messages related to Mach-O symbols
316 set debug notification
317 show debug notification
318 Control display of debugging info for async remote notification.
322 ** Command parameter changes are now notified using new async record
323 "=cmd-param-changed".
324 ** Trace frame changes caused by command "tfind" are now notified using
325 new async record "=traceframe-changed".
326 ** The creation, deletion and modification of trace state variables
327 are now notified using new async records "=tsv-created",
328 "=tsv-deleted" and "=tsv-modified".
329 ** The start and stop of process record are now notified using new
330 async record "=record-started" and "=record-stopped".
331 ** Memory changes are now notified using new async record
333 ** The data-disassemble command response will include a "fullname" field
334 containing the absolute file name when source has been requested.
335 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
336 command, to allow pattern filling of memory areas.
337 ** New commands "-catch-load"/"-catch-unload" added for intercepting
338 library load/unload events.
339 ** The response to breakpoint commands and breakpoint async records
340 includes an "installed" field containing a boolean state about each
341 non-pending tracepoint location is whether installed on target or not.
342 ** Output of the "-trace-status" command includes a "trace-file" field
343 containing the name of the trace file being examined. This field is
344 optional, and only present when examining a trace file.
345 ** The "fullname" field is now always present along with the "file" field,
346 even if the file cannot be found by GDB.
348 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
349 You must have the LZMA library available when configuring GDB for this
350 feature to be enabled. For more information, see:
351 http://fedoraproject.org/wiki/Features/MiniDebugInfo
356 Set the size of trace buffer. The remote stub reports support for this
357 packet to gdb's qSupported query.
360 Enable Branch Trace Store (BTS)-based branch tracing for the current
361 thread. The remote stub reports support for this packet to gdb's
365 Disable branch tracing for the current thread. The remote stub reports
366 support for this packet to gdb's qSupported query.
369 Read the traced branches for the current thread. The remote stub
370 reports support for this packet to gdb's qSupported query.
372 *** Changes in GDB 7.5
374 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
375 for more x32 ABI info.
377 * GDB now supports access to MIPS DSP registers on Linux targets.
379 * GDB now supports debugging microMIPS binaries.
381 * The "info os" command on GNU/Linux can now display information on
382 several new classes of objects managed by the operating system:
383 "info os procgroups" lists process groups
384 "info os files" lists file descriptors
385 "info os sockets" lists internet-domain sockets
386 "info os shm" lists shared-memory regions
387 "info os semaphores" lists semaphores
388 "info os msg" lists message queues
389 "info os modules" lists loaded kernel modules
391 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
392 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
393 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
394 options and inspect the probe arguments using the new $_probe_arg family
395 of convenience variables. You can obtain more information about SystemTap
396 in <http://sourceware.org/systemtap/>.
398 * GDB now supports reversible debugging on ARM, it allows you to
399 debug basic ARM and THUMB instructions, and provides
400 record/replay support.
402 * The option "symbol-reloading" has been deleted as it is no longer used.
406 ** GDB commands implemented in Python can now be put in command class
409 ** The "maint set python print-stack on|off" is now deleted.
411 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
412 apply "flag enum"-style pretty-printing to any enum.
414 ** gdb.lookup_symbol can now work when there is no current frame.
416 ** gdb.Symbol now has a 'line' attribute, holding the line number in
417 the source at which the symbol was defined.
419 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
420 method 'value'. The former indicates whether the symbol needs a
421 frame in order to compute its value, and the latter computes the
424 ** A new method 'referenced_value' on gdb.Value objects which can
425 dereference pointer as well as C++ reference values.
427 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
428 which return the global and static blocks (as gdb.Block objects),
429 of the underlying symbol table, respectively.
431 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
432 object associated with a PC value.
434 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
435 of the address range occupied by code for the current source line.
437 * Go language support.
438 GDB now supports debugging programs written in the Go programming
441 * GDBserver now supports stdio connections.
442 E.g. (gdb) target remote | ssh myhost gdbserver - hello
444 * The binary "gdbtui" can no longer be built or installed.
445 Use "gdb -tui" instead.
447 * GDB will now print "flag" enums specially. A flag enum is one where
448 all the enumerator values have no bits in common when pairwise
449 "and"ed. When printing a value whose type is a flag enum, GDB will
450 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
451 (gdb) print (enum E) 3
454 * The filename part of a linespec will now match trailing components
455 of a source file name. For example, "break gcc/expr.c:1000" will
456 now set a breakpoint in build/gcc/expr.c, but not
459 * The "info proc" and "generate-core-file" commands will now also
460 work on remote targets connected to GDBserver on Linux.
462 * The command "info catch" has been removed. It has been disabled
465 * The "catch exception" and "catch assert" commands now accept
466 a condition at the end of the command, much like the "break"
467 command does. For instance:
469 (gdb) catch exception Constraint_Error if Barrier = True
471 Previously, it was possible to add a condition to such catchpoints,
472 but it had to be done as a second step, after the catchpoint had been
473 created, using the "condition" command.
475 * The "info static-tracepoint-marker" command will now also work on
476 native Linux targets with in-process agent.
478 * GDB can now set breakpoints on inlined functions.
480 * The .gdb_index section has been updated to include symbols for
481 inlined functions. GDB will ignore older .gdb_index sections by
482 default, which could cause symbol files to be loaded more slowly
483 until their .gdb_index sections can be recreated. The new command
484 "set use-deprecated-index-sections on" will cause GDB to use any older
485 .gdb_index sections it finds. This will restore performance, but the
486 ability to set breakpoints on inlined functions will be lost in symbol
487 files with older .gdb_index sections.
489 The .gdb_index section has also been updated to record more information
490 about each symbol. This speeds up the "info variables", "info functions"
491 and "info types" commands when used with programs having the .gdb_index
492 section, as well as speeding up debugging with shared libraries using
493 the .gdb_index section.
495 * Ada support for GDB/MI Variable Objects has been added.
497 * GDB can now support 'breakpoint always-inserted mode' in 'record'
502 ** New command -info-os is the MI equivalent of "info os".
504 ** Output logs ("set logging" and related) now include MI output.
508 ** "set use-deprecated-index-sections on|off"
509 "show use-deprecated-index-sections on|off"
510 Controls the use of deprecated .gdb_index sections.
512 ** "catch load" and "catch unload" can be used to stop when a shared
513 library is loaded or unloaded, respectively.
515 ** "enable count" can be used to auto-disable a breakpoint after
518 ** "info vtbl" can be used to show the virtual method tables for
519 C++ and Java objects.
521 ** "explore" and its sub commands "explore value" and "explore type"
522 can be used to reccursively explore values and types of
523 expressions. These commands are available only if GDB is
524 configured with '--with-python'.
526 ** "info auto-load" shows status of all kinds of auto-loaded files,
527 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
528 sequences of commands files, "info auto-load python-scripts"
529 shows status of auto-loading Python script files,
530 "info auto-load local-gdbinit" shows status of loading init file
531 (.gdbinit) from current directory and "info auto-load libthread-db" shows
532 status of inferior specific thread debugging shared library loading.
534 ** "info auto-load-scripts", "set auto-load-scripts on|off"
535 and "show auto-load-scripts" commands have been deprecated, use their
536 "info auto-load python-scripts", "set auto-load python-scripts on|off"
537 and "show auto-load python-scripts" counterparts instead.
539 ** "dprintf location,format,args..." creates a dynamic printf, which
540 is basically a breakpoint that does a printf and immediately
541 resumes your program's execution, so it is like a printf that you
542 can insert dynamically at runtime instead of at compiletime.
544 ** "set print symbol"
546 Controls whether GDB attempts to display the symbol, if any,
547 corresponding to addresses it prints. This defaults to "on", but
548 you can set it to "off" to restore GDB's previous behavior.
550 * Deprecated commands
552 ** For the Renesas Super-H architecture, the "regs" command has been
553 deprecated, and "info all-registers" should be used instead.
557 Renesas RL78 rl78-*-elf
558 HP OpenVMS ia64 ia64-hp-openvms*
560 * GDBserver supports evaluation of breakpoint conditions. When
561 support is advertised by GDBserver, GDB may be told to send the
562 breakpoint conditions in bytecode form to GDBserver. GDBserver
563 will only report the breakpoint trigger to GDB when its condition
569 show mips compression
570 Select the compressed ISA encoding used in functions that have no symbol
571 information available. The encoding can be set to either of:
574 and is updated automatically from ELF file flags if available.
576 set breakpoint condition-evaluation
577 show breakpoint condition-evaluation
578 Control whether breakpoint conditions are evaluated by GDB ("host") or by
579 GDBserver ("target"). Default option "auto" chooses the most efficient
581 This option can improve debugger efficiency depending on the speed of the
585 Disable auto-loading globally.
588 Show auto-loading setting of all kinds of auto-loaded files.
590 set auto-load gdb-scripts on|off
591 show auto-load gdb-scripts
592 Control auto-loading of GDB canned sequences of commands files.
594 set auto-load python-scripts on|off
595 show auto-load python-scripts
596 Control auto-loading of Python script files.
598 set auto-load local-gdbinit on|off
599 show auto-load local-gdbinit
600 Control loading of init file (.gdbinit) from current directory.
602 set auto-load libthread-db on|off
603 show auto-load libthread-db
604 Control auto-loading of inferior specific thread debugging shared library.
606 set auto-load scripts-directory <dir1>[:<dir2>...]
607 show auto-load scripts-directory
608 Set a list of directories from which to load auto-loaded scripts.
609 Automatically loaded Python scripts and GDB scripts are located in one
610 of the directories listed by this option.
611 The delimiter (':' above) may differ according to the host platform.
613 set auto-load safe-path <dir1>[:<dir2>...]
614 show auto-load safe-path
615 Set a list of directories from which it is safe to auto-load files.
616 The delimiter (':' above) may differ according to the host platform.
618 set debug auto-load on|off
620 Control display of debugging info for auto-loading the files above.
622 set dprintf-style gdb|call|agent
624 Control the way in which a dynamic printf is performed; "gdb"
625 requests a GDB printf command, while "call" causes dprintf to call a
626 function in the inferior. "agent" requests that the target agent
627 (such as GDBserver) do the printing.
629 set dprintf-function <expr>
630 show dprintf-function
631 set dprintf-channel <expr>
633 Set the function and optional first argument to the call when using
634 the "call" style of dynamic printf.
636 set disconnected-dprintf on|off
637 show disconnected-dprintf
638 Control whether agent-style dynamic printfs continue to be in effect
639 after GDB disconnects.
641 * New configure options
644 Configure default value for the 'set auto-load scripts-directory'
645 setting above. It defaults to '$debugdir:$datadir/auto-load',
646 $debugdir representing global debugging info directories (available
647 via 'show debug-file-directory') and $datadir representing GDB's data
648 directory (available via 'show data-directory').
650 --with-auto-load-safe-path
651 Configure default value for the 'set auto-load safe-path' setting
652 above. It defaults to the --with-auto-load-dir setting.
654 --without-auto-load-safe-path
655 Set 'set auto-load safe-path' to '/', effectively disabling this
660 z0/z1 conditional breakpoints extension
662 The z0/z1 breakpoint insertion packets have been extended to carry
663 a list of conditional expressions over to the remote stub depending on the
664 condition evaluation mode. The use of this extension can be controlled
665 via the "set remote conditional-breakpoints-packet" command.
669 Specify the signals which the remote stub may pass to the debugged
670 program without GDB involvement.
672 * New command line options
674 --init-command=FILE, -ix Like --command, -x but execute it
675 before loading inferior.
676 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
677 execute it before loading inferior.
679 *** Changes in GDB 7.4
681 * GDB now handles ambiguous linespecs more consistently; the existing
682 FILE:LINE support has been expanded to other types of linespecs. A
683 breakpoint will now be set on all matching locations in all
684 inferiors, and locations will be added or removed according to
687 * GDB now allows you to skip uninteresting functions and files when
688 stepping with the "skip function" and "skip file" commands.
690 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
691 and "show remote hardware-watchpoint-length-limit". These allows to
692 set or show the maximum length limit (in bytes) of a remote
693 target hardware watchpoint.
695 This allows e.g. to use "unlimited" hardware watchpoints with the
696 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
697 watchpoints are slower than real hardware watchpoints but are
698 significantly faster than gdb software watchpoints.
702 ** The register_pretty_printer function in module gdb.printing now takes
703 an optional `replace' argument. If True, the new printer replaces any
706 ** The "maint set python print-stack on|off" command has been
707 deprecated and will be deleted in GDB 7.5.
708 A new command: "set python print-stack none|full|message" has
709 replaced it. Additionally, the default for "print-stack" is
710 now "message", which just prints the error message without
713 ** A prompt substitution hook (prompt_hook) is now available to the
716 ** A new Python module, gdb.prompt has been added to the GDB Python
717 modules library. This module provides functionality for
718 escape sequences in prompts (used by set/show
719 extended-prompt). These escape sequences are replaced by their
722 ** Python commands and convenience-functions located in
723 'data-directory'/python/gdb/command and
724 'data-directory'/python/gdb/function are now automatically loaded
727 ** Blocks now provide four new attributes. global_block and
728 static_block will return the global and static blocks
729 respectively. is_static and is_global are boolean attributes
730 that indicate if the block is one of those two types.
732 ** Symbols now provide the "type" attribute, the type of the symbol.
734 ** The "gdb.breakpoint" function has been deprecated in favor of
737 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
738 of a function. This class is based on the "finish" command
739 available in the CLI.
741 ** Type objects for struct and union types now allow access to
742 the fields using standard Python dictionary (mapping) methods.
743 For example, "some_type['myfield']" now works, as does
746 ** A new event "gdb.new_objfile" has been added, triggered by loading a
749 ** A new function, "deep_items" has been added to the gdb.types
750 module in the GDB Python modules library. This function returns
751 an iterator over the fields of a struct or union type. Unlike
752 the standard Python "iteritems" method, it will recursively traverse
753 any anonymous fields.
757 ** "*stopped" events can report several new "reason"s, such as
760 ** Breakpoint changes are now notified using new async records, like
761 "=breakpoint-modified".
763 ** New command -ada-task-info.
765 * libthread-db-search-path now supports two special values: $sdir and $pdir.
766 $sdir specifies the default system locations of shared libraries.
767 $pdir specifies the directory where the libpthread used by the application
770 GDB no longer looks in $sdir and $pdir after it has searched the directories
771 mentioned in libthread-db-search-path. If you want to search those
772 directories, they must be specified in libthread-db-search-path.
773 The default value of libthread-db-search-path on GNU/Linux and Solaris
774 systems is now "$sdir:$pdir".
776 $pdir is not supported by gdbserver, it is currently ignored.
777 $sdir is supported by gdbserver.
779 * New configure option --with-iconv-bin.
780 When using the internationalization support like the one in the GNU C
781 library, GDB will invoke the "iconv" program to get a list of supported
782 character sets. If this program lives in a non-standard location, one can
783 use this option to specify where to find it.
785 * When natively debugging programs on PowerPC BookE processors running
786 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
787 watchpoints, which specify a mask in addition to an address to watch.
788 The mask specifies that some bits of an address (the bits which are
789 reset in the mask) should be ignored when matching the address accessed
790 by the inferior against the watchpoint address. See the "PowerPC Embedded"
791 section in the user manual for more details.
793 * The new option --once causes GDBserver to stop listening for connections once
794 the first connection is made. The listening port used by GDBserver will
795 become available after that.
797 * New commands "info macros" and "alias" have been added.
799 * New function parameters suffix @entry specifies value of function parameter
800 at the time the function got called. Entry values are available only since
806 "!" is now an alias of the "shell" command.
807 Note that no space is needed between "!" and SHELL COMMAND.
811 watch EXPRESSION mask MASK_VALUE
812 The watch command now supports the mask argument which allows creation
813 of masked watchpoints, if the current architecture supports this feature.
815 info auto-load-scripts [REGEXP]
816 This command was formerly named "maintenance print section-scripts".
817 It is now generally useful and is no longer a maintenance-only command.
819 info macro [-all] [--] MACRO
820 The info macro command has new options `-all' and `--'. The first for
821 printing all definitions of a macro. The second for explicitly specifying
822 the end of arguments and the beginning of the macro name in case the macro
823 name starts with a hyphen.
825 collect[/s] EXPRESSIONS
826 The tracepoint collect command now takes an optional modifier "/s"
827 that directs it to dereference pointer-to-character types and
828 collect the bytes of memory up to a zero byte. The behavior is
829 similar to what you see when you use the regular print command on a
830 string. An optional integer following the "/s" sets a bound on the
831 number of bytes that will be collected.
834 The trace start command now interprets any supplied arguments as a
835 note to be recorded with the trace run, with an effect similar to
836 setting the variable trace-notes.
839 The trace stop command now interprets any arguments as a note to be
840 mentioned along with the tstatus report that the trace was stopped
841 with a command. The effect is similar to setting the variable
844 * Tracepoints can now be enabled and disabled at any time after a trace
845 experiment has been started using the standard "enable" and "disable"
846 commands. It is now possible to start a trace experiment with no enabled
847 tracepoints; GDB will display a warning, but will allow the experiment to
848 begin, assuming that tracepoints will be enabled as needed while the trace
851 * Fast tracepoints on 32-bit x86-architectures can now be placed at
852 locations with 4-byte instructions, when they were previously
853 limited to locations with instructions of 5 bytes or longer.
857 set debug dwarf2-read
858 show debug dwarf2-read
859 Turns on or off display of debugging messages related to reading
860 DWARF debug info. The default is off.
862 set debug symtab-create
863 show debug symtab-create
864 Turns on or off display of debugging messages related to symbol table
865 creation. The default is off.
869 Set the GDB prompt, and allow escape sequences to be inserted to
870 display miscellaneous information (see 'help set extended-prompt'
871 for the list of sequences). This prompt (and any information
872 accessed through the escape sequences) is updated every time the
875 set print entry-values (both|compact|default|if-needed|no|only|preferred)
876 show print entry-values
877 Set printing of frame argument values at function entry. In some cases
878 GDB can determine the value of function argument which was passed by the
879 function caller, even if the value was modified inside the called function.
881 set debug entry-values
882 show debug entry-values
883 Control display of debugging info for determining frame argument values at
884 function entry and virtual tail call frames.
886 set basenames-may-differ
887 show basenames-may-differ
888 Set whether a source file may have multiple base names.
889 (A "base name" is the name of a file with the directory part removed.
890 Example: The base name of "/home/user/hello.c" is "hello.c".)
891 If set, GDB will canonicalize file names (e.g., expand symlinks)
892 before comparing them. Canonicalization is an expensive operation,
893 but it allows the same file be known by more than one base name.
894 If not set (the default), all source files are assumed to have just
895 one base name, and gdb will do file name comparisons more efficiently.
901 Set a user name and notes for the current and any future trace runs.
902 This is useful for long-running and/or disconnected traces, to
903 inform others (or yourself) as to who is running the trace, supply
904 contact information, or otherwise explain what is going on.
907 show trace-stop-notes
908 Set a note attached to the trace run, that is displayed when the
909 trace has been stopped by a tstop command. This is useful for
910 instance as an explanation, if you are stopping a trace run that was
911 started by someone else.
917 Dynamically enable a tracepoint in a started trace experiment.
921 Dynamically disable a tracepoint in a started trace experiment.
925 Set the user and notes of the trace run.
929 Query the current status of a tracepoint.
933 Query the minimum length of instruction at which a fast tracepoint may
936 * Dcache size (number of lines) and line-size are now runtime-configurable
937 via "set dcache line" and "set dcache line-size" commands.
941 Texas Instruments TMS320C6x tic6x-*-*
945 Renesas RL78 rl78-*-elf
947 *** Changes in GDB 7.3.1
949 * The build failure for NetBSD and OpenBSD targets have now been fixed.
951 *** Changes in GDB 7.3
953 * GDB has a new command: "thread find [REGEXP]".
954 It finds the thread id whose name, target id, or thread extra info
955 matches the given regular expression.
957 * The "catch syscall" command now works on mips*-linux* targets.
959 * The -data-disassemble MI command now supports modes 2 and 3 for
960 dumping the instruction opcodes.
962 * New command line options
964 -data-directory DIR Specify DIR as the "data-directory".
965 This is mostly for testing purposes.
967 * The "maint set python auto-load on|off" command has been renamed to
968 "set auto-load-scripts on|off".
970 * GDB has a new command: "set directories".
971 It is like the "dir" command except that it replaces the
972 source path list instead of augmenting it.
974 * GDB now understands thread names.
976 On GNU/Linux, "info threads" will display the thread name as set by
977 prctl or pthread_setname_np.
979 There is also a new command, "thread name", which can be used to
980 assign a name internally for GDB to display.
983 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
984 has been integrated into GDB.
988 ** The function gdb.Write now accepts an optional keyword 'stream'.
989 This keyword, when provided, will direct the output to either
990 stdout, stderr, or GDB's logging output.
992 ** Parameters can now be be sub-classed in Python, and in particular
993 you may implement the get_set_doc and get_show_doc functions.
994 This improves how Parameter set/show documentation is processed
995 and allows for more dynamic content.
997 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
998 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
999 have an is_valid method.
1001 ** Breakpoints can now be sub-classed in Python, and in particular
1002 you may implement a 'stop' function that is executed each time
1003 the inferior reaches that breakpoint.
1005 ** New function gdb.lookup_global_symbol looks up a global symbol.
1007 ** GDB values in Python are now callable if the value represents a
1008 function. For example, if 'some_value' represents a function that
1009 takes two integer parameters and returns a value, you can call
1010 that function like so:
1012 result = some_value (10,20)
1014 ** Module gdb.types has been added.
1015 It contains a collection of utilities for working with gdb.Types objects:
1016 get_basic_type, has_field, make_enum_dict.
1018 ** Module gdb.printing has been added.
1019 It contains utilities for writing and registering pretty-printers.
1020 New classes: PrettyPrinter, SubPrettyPrinter,
1021 RegexpCollectionPrettyPrinter.
1022 New function: register_pretty_printer.
1024 ** New commands "info pretty-printers", "enable pretty-printer" and
1025 "disable pretty-printer" have been added.
1027 ** gdb.parameter("directories") is now available.
1029 ** New function gdb.newest_frame returns the newest frame in the
1032 ** The gdb.InferiorThread class has a new "name" attribute. This
1033 holds the thread's name.
1035 ** Python Support for Inferior events.
1036 Python scripts can add observers to be notified of events
1037 occurring in the process being debugged.
1038 The following events are currently supported:
1039 - gdb.events.cont Continue event.
1040 - gdb.events.exited Inferior exited event.
1041 - gdb.events.stop Signal received, and Breakpoint hit events.
1045 ** GDB now puts template parameters in scope when debugging in an
1046 instantiation. For example, if you have:
1048 template<int X> int func (void) { return X; }
1050 then if you step into func<5>, "print X" will show "5". This
1051 feature requires proper debuginfo support from the compiler; it
1052 was added to GCC 4.5.
1054 ** The motion commands "next", "finish", "until", and "advance" now
1055 work better when exceptions are thrown. In particular, GDB will
1056 no longer lose control of the inferior; instead, the GDB will
1057 stop the inferior at the point at which the exception is caught.
1058 This functionality requires a change in the exception handling
1059 code that was introduced in GCC 4.5.
1061 * GDB now follows GCC's rules on accessing volatile objects when
1062 reading or writing target state during expression evaluation.
1063 One notable difference to prior behavior is that "print x = 0"
1064 no longer generates a read of x; the value of the assignment is
1065 now always taken directly from the value being assigned.
1067 * GDB now has some support for using labels in the program's source in
1068 linespecs. For instance, you can use "advance label" to continue
1069 execution to a label.
1071 * GDB now has support for reading and writing a new .gdb_index
1072 section. This section holds a fast index of DWARF debugging
1073 information and can be used to greatly speed up GDB startup and
1074 operation. See the documentation for `save gdb-index' for details.
1076 * The "watch" command now accepts an optional "-location" argument.
1077 When used, this causes GDB to watch the memory referred to by the
1078 expression. Such a watchpoint is never deleted due to it going out
1081 * GDB now supports thread debugging of core dumps on GNU/Linux.
1083 GDB now activates thread debugging using the libthread_db library
1084 when debugging GNU/Linux core dumps, similarly to when debugging
1085 live processes. As a result, when debugging a core dump file, GDB
1086 is now able to display pthread_t ids of threads. For example, "info
1087 threads" shows the same output as when debugging the process when it
1088 was live. In earlier releases, you'd see something like this:
1091 * 1 LWP 6780 main () at main.c:10
1093 While now you see this:
1096 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1098 It is also now possible to inspect TLS variables when debugging core
1101 When debugging a core dump generated on a machine other than the one
1102 used to run GDB, you may need to point GDB at the correct
1103 libthread_db library with the "set libthread-db-search-path"
1104 command. See the user manual for more details on this command.
1106 * When natively debugging programs on PowerPC BookE processors running
1107 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1108 which stop execution of the inferior whenever it executes an instruction
1109 at any address within the specified range. See the "PowerPC Embedded"
1110 section in the user manual for more details.
1112 * New features in the GDB remote stub, GDBserver
1114 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1115 and i686 LynxOS (version 5.x).
1117 ** GDBserver is now supported on Blackfin Linux.
1119 * New native configurations
1121 ia64 HP-UX ia64-*-hpux*
1125 Analog Devices, Inc. Blackfin Processor bfin-*
1127 * Ada task switching is now supported on sparc-elf targets when
1128 debugging a program using the Ravenscar Profile. For more information,
1129 see the "Tasking Support when using the Ravenscar Profile" section
1130 in the GDB user manual.
1132 * Guile support was removed.
1134 * New features in the GNU simulator
1136 ** The --map-info flag lists all known core mappings.
1138 ** CFI flashes may be simulated via the "cfi" device.
1140 *** Changes in GDB 7.2
1142 * Shared library support for remote targets by default
1144 When GDB is configured for a generic, non-OS specific target, like
1145 for example, --target=arm-eabi or one of the many *-*-elf targets,
1146 GDB now queries remote stubs for loaded shared libraries using the
1147 `qXfer:libraries:read' packet. Previously, shared library support
1148 was always disabled for such configurations.
1152 ** Argument Dependent Lookup (ADL)
1154 In C++ ADL lookup directs function search to the namespaces of its
1155 arguments even if the namespace has not been imported.
1165 Here the compiler will search for `foo' in the namespace of 'b'
1166 and find A::foo. GDB now supports this. This construct is commonly
1167 used in the Standard Template Library for operators.
1169 ** Improved User Defined Operator Support
1171 In addition to member operators, GDB now supports lookup of operators
1172 defined in a namespace and imported with a `using' directive, operators
1173 defined in the global scope, operators imported implicitly from an
1174 anonymous namespace, and the ADL operators mentioned in the previous
1176 GDB now also supports proper overload resolution for all the previously
1177 mentioned flavors of operators.
1179 ** static const class members
1181 Printing of static const class members that are initialized in the
1182 class definition has been fixed.
1184 * Windows Thread Information Block access.
1186 On Windows targets, GDB now supports displaying the Windows Thread
1187 Information Block (TIB) structure. This structure is visible either
1188 by using the new command `info w32 thread-information-block' or, by
1189 dereferencing the new convenience variable named `$_tlb', a
1190 thread-specific pointer to the TIB. This feature is also supported
1191 when remote debugging using GDBserver.
1193 * Static tracepoints
1195 Static tracepoints are calls in the user program into a tracing
1196 library. One such library is a port of the LTTng kernel tracer to
1197 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1198 When debugging with GDBserver, GDB now supports combining the GDB
1199 tracepoint machinery with such libraries. For example: the user can
1200 use GDB to probe a static tracepoint marker (a call from the user
1201 program into the tracing library) with the new "strace" command (see
1202 "New commands" below). This creates a "static tracepoint" in the
1203 breakpoint list, that can be manipulated with the same feature set
1204 as fast and regular tracepoints. E.g., collect registers, local and
1205 global variables, collect trace state variables, and define
1206 tracepoint conditions. In addition, the user can collect extra
1207 static tracepoint marker specific data, by collecting the new
1208 $_sdata internal variable. When analyzing the trace buffer, you can
1209 inspect $_sdata like any other variable available to GDB. For more
1210 information, see the "Tracepoints" chapter in GDB user manual. New
1211 remote packets have been defined to support static tracepoints, see
1212 the "New remote packets" section below.
1214 * Better reconstruction of tracepoints after disconnected tracing
1216 GDB will attempt to download the original source form of tracepoint
1217 definitions when starting a trace run, and then will upload these
1218 upon reconnection to the target, resulting in a more accurate
1219 reconstruction of the tracepoints that are in use on the target.
1223 You can now exercise direct control over the ways that GDB can
1224 affect your program. For instance, you can disallow the setting of
1225 breakpoints, so that the program can run continuously (assuming
1226 non-stop mode). In addition, the "observer" variable is available
1227 to switch all of the different controls; in observer mode, GDB
1228 cannot affect the target's behavior at all, which is useful for
1229 tasks like diagnosing live systems in the field.
1231 * The new convenience variable $_thread holds the number of the
1234 * New remote packets
1238 Return the address of the Windows Thread Information Block of a given thread.
1242 In response to several of the tracepoint packets, the target may now
1243 also respond with a number of intermediate `qRelocInsn' request
1244 packets before the final result packet, to have GDB handle
1245 relocating an instruction to execute at a different address. This
1246 is particularly useful for stubs that support fast tracepoints. GDB
1247 reports support for this feature in the qSupported packet.
1251 List static tracepoint markers in the target program.
1255 List static tracepoint markers at a given address in the target
1258 qXfer:statictrace:read
1260 Read the static trace data collected (by a `collect $_sdata'
1261 tracepoint action). The remote stub reports support for this packet
1262 to gdb's qSupported query.
1266 Send the current settings of GDB's permission flags.
1270 Send part of the source (textual) form of a tracepoint definition,
1271 which includes location, conditional, and action list.
1273 * The source command now accepts a -s option to force searching for the
1274 script in the source search path even if the script name specifies
1277 * New features in the GDB remote stub, GDBserver
1279 - GDBserver now support tracepoints (including fast tracepoints, and
1280 static tracepoints). The feature is currently supported by the
1281 i386-linux and amd64-linux builds. See the "Tracepoints support
1282 in gdbserver" section in the manual for more information.
1284 GDBserver JIT compiles the tracepoint's conditional agent
1285 expression bytecode into native code whenever possible for low
1286 overhead dynamic tracepoints conditionals. For such tracepoints,
1287 an expression that examines program state is evaluated when the
1288 tracepoint is reached, in order to determine whether to capture
1289 trace data. If the condition is simple and false, processing the
1290 tracepoint finishes very quickly and no data is gathered.
1292 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1293 for static tracepoints support.
1295 - GDBserver now supports x86_64 Windows 64-bit debugging.
1297 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1298 it understands register description.
1300 * The --batch flag now disables pagination and queries.
1302 * X86 general purpose registers
1304 GDB now supports reading/writing byte, word and double-word x86
1305 general purpose registers directly. This means you can use, say,
1306 $ah or $ax to refer, respectively, to the byte register AH and
1307 16-bit word register AX that are actually portions of the 32-bit
1308 register EAX or 64-bit register RAX.
1310 * The `commands' command now accepts a range of breakpoints to modify.
1311 A plain `commands' following a command that creates multiple
1312 breakpoints affects all the breakpoints set by that command. This
1313 applies to breakpoints set by `rbreak', and also applies when a
1314 single `break' command creates multiple breakpoints (e.g.,
1315 breakpoints on overloaded c++ functions).
1317 * The `rbreak' command now accepts a filename specification as part of
1318 its argument, limiting the functions selected by the regex to those
1319 in the specified file.
1321 * Support for remote debugging Windows and SymbianOS shared libraries
1322 from Unix hosts has been improved. Non Windows GDB builds now can
1323 understand target reported file names that follow MS-DOS based file
1324 system semantics, such as file names that include drive letters and
1325 use the backslash character as directory separator. This makes it
1326 possible to transparently use the "set sysroot" and "set
1327 solib-search-path" on Unix hosts to point as host copies of the
1328 target's shared libraries. See the new command "set
1329 target-file-system-kind" described below, and the "Commands to
1330 specify files" section in the user manual for more information.
1334 eval template, expressions...
1335 Convert the values of one or more expressions under the control
1336 of the string template to a command line, and call it.
1338 set target-file-system-kind unix|dos-based|auto
1339 show target-file-system-kind
1340 Set or show the assumed file system kind for target reported file
1343 save breakpoints <filename>
1344 Save all current breakpoint definitions to a file suitable for use
1345 in a later debugging session. To read the saved breakpoint
1346 definitions, use the `source' command.
1348 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1351 info static-tracepoint-markers
1352 Display information about static tracepoint markers in the target.
1354 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1355 Define a static tracepoint by probing a marker at the given
1356 function, line, address, or marker ID.
1360 Enable and disable observer mode.
1362 set may-write-registers on|off
1363 set may-write-memory on|off
1364 set may-insert-breakpoints on|off
1365 set may-insert-tracepoints on|off
1366 set may-insert-fast-tracepoints on|off
1367 set may-interrupt on|off
1368 Set individual permissions for GDB effects on the target. Note that
1369 some of these settings can have undesirable or surprising
1370 consequences, particularly when changed in the middle of a session.
1371 For instance, disabling the writing of memory can prevent
1372 breakpoints from being inserted, cause single-stepping to fail, or
1373 even crash your program, if you disable after breakpoints have been
1374 inserted. However, GDB should not crash.
1376 set record memory-query on|off
1377 show record memory-query
1378 Control whether to stop the inferior if memory changes caused
1379 by an instruction cannot be recorded.
1384 The disassemble command now supports "start,+length" form of two arguments.
1388 ** GDB now provides a new directory location, called the python directory,
1389 where Python scripts written for GDB can be installed. The location
1390 of that directory is <data-directory>/python, where <data-directory>
1391 is the GDB data directory. For more details, see section `Scripting
1392 GDB using Python' in the manual.
1394 ** The GDB Python API now has access to breakpoints, symbols, symbol
1395 tables, program spaces, inferiors, threads and frame's code blocks.
1396 Additionally, GDB Parameters can now be created from the API, and
1397 manipulated via set/show in the CLI.
1399 ** New functions gdb.target_charset, gdb.target_wide_charset,
1400 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1402 ** New exception gdb.GdbError.
1404 ** Pretty-printers are now also looked up in the current program space.
1406 ** Pretty-printers can now be individually enabled and disabled.
1408 ** GDB now looks for names of Python scripts to auto-load in a
1409 special section named `.debug_gdb_scripts', in addition to looking
1410 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1412 * Tracepoint actions were unified with breakpoint commands. In particular,
1413 there are no longer differences in "info break" output for breakpoints and
1414 tracepoints and the "commands" command can be used for both tracepoints and
1415 regular breakpoints.
1419 ARM Symbian arm*-*-symbianelf*
1421 * D language support.
1422 GDB now supports debugging programs written in the D programming
1425 * GDB now supports the extended ptrace interface for PowerPC which is
1426 available since Linux kernel version 2.6.34. This automatically enables
1427 any hardware breakpoints and additional hardware watchpoints available in
1428 the processor. The old ptrace interface exposes just one hardware
1429 watchpoint and no hardware breakpoints.
1431 * GDB is now able to use the Data Value Compare (DVC) register available on
1432 embedded PowerPC processors to implement in hardware simple watchpoint
1433 conditions of the form:
1435 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1437 This works in native GDB running on Linux kernels with the extended ptrace
1438 interface mentioned above.
1440 *** Changes in GDB 7.1
1444 ** Namespace Support
1446 GDB now supports importing of namespaces in C++. This enables the
1447 user to inspect variables from imported namespaces. Support for
1448 namepace aliasing has also been added. So, if a namespace is
1449 aliased in the current scope (e.g. namepace C=A; ) the user can
1450 print variables using the alias (e.g. (gdb) print C::x).
1454 All known bugs relating to the printing of virtual base class were
1455 fixed. It is now possible to call overloaded static methods using a
1460 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1461 and reinterpret_cast<> are now handled by the C++ expression parser.
1465 Xilinx MicroBlaze microblaze-*-*
1470 Xilinx MicroBlaze microblaze
1473 * Multi-program debugging.
1475 GDB now has support for multi-program (a.k.a. multi-executable or
1476 multi-exec) debugging. This allows for debugging multiple inferiors
1477 simultaneously each running a different program under the same GDB
1478 session. See "Debugging Multiple Inferiors and Programs" in the
1479 manual for more information. This implied some user visible changes
1480 in the multi-inferior support. For example, "info inferiors" now
1481 lists inferiors that are not running yet or that have exited
1482 already. See also "New commands" and "New options" below.
1484 * New tracing features
1486 GDB's tracepoint facility now includes several new features:
1488 ** Trace state variables
1490 GDB tracepoints now include support for trace state variables, which
1491 are variables managed by the target agent during a tracing
1492 experiment. They are useful for tracepoints that trigger each
1493 other, so for instance one tracepoint can count hits in a variable,
1494 and then a second tracepoint has a condition that is true when the
1495 count reaches a particular value. Trace state variables share the
1496 $-syntax of GDB convenience variables, and can appear in both
1497 tracepoint actions and condition expressions. Use the "tvariable"
1498 command to create, and "info tvariables" to view; see "Trace State
1499 Variables" in the manual for more detail.
1503 GDB now includes an option for defining fast tracepoints, which
1504 targets may implement more efficiently, such as by installing a jump
1505 into the target agent rather than a trap instruction. The resulting
1506 speedup can be by two orders of magnitude or more, although the
1507 tradeoff is that some program locations on some target architectures
1508 might not allow fast tracepoint installation, for instance if the
1509 instruction to be replaced is shorter than the jump. To request a
1510 fast tracepoint, use the "ftrace" command, with syntax identical to
1511 the regular trace command.
1513 ** Disconnected tracing
1515 It is now possible to detach GDB from the target while it is running
1516 a trace experiment, then reconnect later to see how the experiment
1517 is going. In addition, a new variable disconnected-tracing lets you
1518 tell the target agent whether to continue running a trace if the
1519 connection is lost unexpectedly.
1523 GDB now has the ability to save the trace buffer into a file, and
1524 then use that file as a target, similarly to you can do with
1525 corefiles. You can select trace frames, print data that was
1526 collected in them, and use tstatus to display the state of the
1527 tracing run at the moment that it was saved. To create a trace
1528 file, use "tsave <filename>", and to use it, do "target tfile
1531 ** Circular trace buffer
1533 You can ask the target agent to handle the trace buffer as a
1534 circular buffer, discarding the oldest trace frames to make room for
1535 newer ones, by setting circular-trace-buffer to on. This feature may
1536 not be available for all target agents.
1541 The disassemble command, when invoked with two arguments, now requires
1542 the arguments to be comma-separated.
1545 The info variables command now displays variable definitions. Files
1546 which only declare a variable are not shown.
1549 The source command is now capable of sourcing Python scripts.
1550 This feature is dependent on the debugger being build with Python
1553 Related to this enhancement is also the introduction of a new command
1554 "set script-extension" (see below).
1556 * New commands (for set/show, see "New options" below)
1558 record save [<FILENAME>]
1559 Save a file (in core file format) containing the process record
1560 execution log for replay debugging at a later time.
1562 record restore <FILENAME>
1563 Restore the process record execution log that was saved at an
1564 earlier time, for replay debugging.
1566 add-inferior [-copies <N>] [-exec <FILENAME>]
1569 clone-inferior [-copies <N>] [ID]
1570 Make a new inferior ready to execute the same program another
1571 inferior has loaded.
1576 maint info program-spaces
1577 List the program spaces loaded into GDB.
1579 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1580 show remote interrupt-sequence
1581 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1582 as the sequence to the remote target in order to interrupt the execution.
1583 Ctrl-C is a default. Some system prefers BREAK which is high level of
1584 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1585 Magic SysRq g. It is BREAK signal and character 'g'.
1587 set remote interrupt-on-connect [on | off]
1588 show remote interrupt-on-connect
1589 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1590 remote target when gdb connects to it. This is needed when you debug
1593 set remotebreak [on | off]
1595 Deprecated. Use "set/show remote interrupt-sequence" instead.
1597 tvariable $NAME [ = EXP ]
1598 Create or modify a trace state variable.
1601 List trace state variables and their values.
1603 delete tvariable $NAME ...
1604 Delete one or more trace state variables.
1607 Evaluate the given expressions without collecting anything into the
1608 trace buffer. (Valid in tracepoint actions only.)
1610 ftrace FN / FILE:LINE / *ADDR
1611 Define a fast tracepoint at the given function, line, or address.
1613 * New expression syntax
1615 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1616 GDB now parses 0b101010 identically with 42.
1620 set follow-exec-mode new|same
1621 show follow-exec-mode
1622 Control whether GDB reuses the same inferior across an exec call or
1623 creates a new one. This is useful to be able to restart the old
1624 executable after the inferior having done an exec call.
1626 set default-collect EXPR, ...
1627 show default-collect
1628 Define a list of expressions to be collected at each tracepoint.
1629 This is a useful way to ensure essential items are not overlooked,
1630 such as registers or a critical global variable.
1632 set disconnected-tracing
1633 show disconnected-tracing
1634 If set to 1, the target is instructed to continue tracing if it
1635 loses its connection to GDB. If 0, the target is to stop tracing
1638 set circular-trace-buffer
1639 show circular-trace-buffer
1640 If set to on, the target is instructed to use a circular trace buffer
1641 and discard the oldest trace frames instead of stopping the trace due
1642 to a full trace buffer. If set to off, the trace stops when the buffer
1643 fills up. Some targets may not support this.
1645 set script-extension off|soft|strict
1646 show script-extension
1647 If set to "off", the debugger does not perform any script language
1648 recognition, and all sourced files are assumed to be GDB scripts.
1649 If set to "soft" (the default), files are sourced according to
1650 filename extension, falling back to GDB scripts if the first
1652 If set to "strict", files are sourced according to filename extension.
1654 set ada trust-PAD-over-XVS on|off
1655 show ada trust-PAD-over-XVS
1656 If off, activate a workaround against a bug in the debugging information
1657 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1658 the GCC sources for more information about the GNAT encoding and
1659 PAD types in particular). It is always safe to set this option to
1660 off, but this introduces a slight performance penalty. The default
1663 * Python API Improvements
1665 ** GDB provides the new class gdb.LazyString. This is useful in
1666 some pretty-printing cases. The new method gdb.Value.lazy_string
1667 provides a simple way to create objects of this type.
1669 ** The fields returned by gdb.Type.fields now have an
1670 `is_base_class' attribute.
1672 ** The new method gdb.Type.range returns the range of an array type.
1674 ** The new method gdb.parse_and_eval can be used to parse and
1675 evaluate an expression.
1677 * New remote packets
1680 Define a trace state variable.
1683 Get the current value of a trace state variable.
1686 Set desired tracing behavior upon disconnection.
1689 Set the trace buffer to be linear or circular.
1692 Get data about the tracepoints currently in use.
1696 Process record now works correctly with hardware watchpoints.
1698 Multiple bug fixes have been made to the mips-irix port, making it
1699 much more reliable. In particular:
1700 - Debugging threaded applications is now possible again. Previously,
1701 GDB would hang while starting the program, or while waiting for
1702 the program to stop at a breakpoint.
1703 - Attaching to a running process no longer hangs.
1704 - An error occurring while loading a core file has been fixed.
1705 - Changing the value of the PC register now works again. This fixes
1706 problems observed when using the "jump" command, or when calling
1707 a function from GDB, or even when assigning a new value to $pc.
1708 - With the "finish" and "return" commands, the return value for functions
1709 returning a small array is now correctly printed.
1710 - It is now possible to break on shared library code which gets executed
1711 during a shared library init phase (code executed while executing
1712 their .init section). Previously, the breakpoint would have no effect.
1713 - GDB is now able to backtrace through the signal handler for
1714 non-threaded programs.
1716 PIE (Position Independent Executable) programs debugging is now supported.
1717 This includes debugging execution of PIC (Position Independent Code) shared
1718 libraries although for that, it should be possible to run such libraries as an
1721 *** Changes in GDB 7.0
1723 * GDB now has an interface for JIT compilation. Applications that
1724 dynamically generate code can create symbol files in memory and register
1725 them with GDB. For users, the feature should work transparently, and
1726 for JIT developers, the interface is documented in the GDB manual in the
1727 "JIT Compilation Interface" chapter.
1729 * Tracepoints may now be conditional. The syntax is as for
1730 breakpoints; either an "if" clause appended to the "trace" command,
1731 or the "condition" command is available. GDB sends the condition to
1732 the target for evaluation using the same bytecode format as is used
1733 for tracepoint actions.
1735 * The disassemble command now supports: an optional /r modifier, print the
1736 raw instructions in hex as well as in symbolic form, and an optional /m
1737 modifier to print mixed source+assembly.
1739 * Process record and replay
1741 In a architecture environment that supports ``process record and
1742 replay'', ``process record and replay'' target can record a log of
1743 the process execution, and replay it with both forward and reverse
1746 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1747 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1748 set execution-direction {forward|reverse}, for targets that support
1751 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1752 feature is available with a native GDB running on kernel version
1755 * GDB now has support for multi-byte and wide character sets on the
1756 target. Strings whose character type is wchar_t, char16_t, or
1757 char32_t are now correctly printed. GDB supports wide- and unicode-
1758 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1759 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1760 `printf'. This feature requires iconv to work properly; if your
1761 system does not have a working iconv, GDB can use GNU libiconv. See
1762 the installation instructions for more information.
1764 * GDB now supports automatic retrieval of shared library files from
1765 remote targets. To use this feature, specify a system root that begins
1766 with the `remote:' prefix, either via the `set sysroot' command or via
1767 the `--with-sysroot' configure-time option.
1769 * "info sharedlibrary" now takes an optional regex of libraries to show,
1770 and it now reports if a shared library has no debugging information.
1772 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1773 now complete on file names.
1775 * When completing in expressions, gdb will attempt to limit
1776 completions to allowable structure or union fields, where appropriate.
1777 For instance, consider:
1779 # struct example { int f1; double f2; };
1780 # struct example variable;
1783 If the user types TAB at the end of this command line, the available
1784 completions will be "f1" and "f2".
1786 * Inlined functions are now supported. They show up in backtraces, and
1787 the "step", "next", and "finish" commands handle them automatically.
1789 * GDB now supports the token-splicing (##) and stringification (#)
1790 operators when expanding macros. It also supports variable-arity
1793 * GDB now supports inspecting extra signal information, exported by
1794 the new $_siginfo convenience variable. The feature is currently
1795 implemented on linux ARM, i386 and amd64.
1797 * GDB can now display the VFP floating point registers and NEON vector
1798 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1799 can provide these registers (requires Linux 2.6.30 or later). Remote
1800 and simulator targets may also provide them.
1802 * New remote packets
1805 Search memory for a sequence of bytes.
1808 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1809 operation over reliable transport links. Use of this packet is
1810 controlled by the `set remote noack-packet' command.
1813 Kill the process with the specified process ID. Use this in preference
1814 to `k' when multiprocess protocol extensions are supported.
1817 Obtains additional operating system information
1821 Read or write additional signal information.
1823 * Removed remote protocol undocumented extension
1825 An undocumented extension to the remote protocol's `S' stop reply
1826 packet that permited the stub to pass a process id was removed.
1827 Remote servers should use the `T' stop reply packet instead.
1829 * GDB now supports multiple function calling conventions according to the
1830 DWARF-2 DW_AT_calling_convention function attribute.
1832 * The SH target utilizes the aforementioned change to distinguish between gcc
1833 and Renesas calling convention. It also adds the new CLI commands
1834 `set/show sh calling-convention'.
1836 * GDB can now read compressed debug sections, as produced by GNU gold
1837 with the --compress-debug-sections=zlib flag.
1839 * 64-bit core files are now supported on AIX.
1841 * Thread switching is now supported on Tru64.
1843 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1844 which will be allocated using malloc later in program execution.
1846 * The qXfer:libraries:read remote procotol packet now allows passing a
1847 list of section offsets.
1849 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1850 conditions handling signals delivered during attach or thread creation
1851 have also been fixed.
1853 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1854 From the user's standpoint, all unqualified instances of True and False
1855 are treated as the standard definitions, regardless of context.
1857 * GDB now parses C++ symbol and type names more flexibly. For
1860 template<typename T> class C { };
1863 GDB will now correctly handle all of:
1865 ptype C<char const *>
1866 ptype C<char const*>
1867 ptype C<const char *>
1868 ptype C<const char*>
1870 * New features in the GDB remote stub, gdbserver
1872 - The "--wrapper" command-line argument tells gdbserver to use a
1873 wrapper program to launch programs for debugging.
1875 - On PowerPC and S/390 targets, it is now possible to use a single
1876 gdbserver executable to debug both 32-bit and 64-bit programs.
1877 (This requires gdbserver itself to be built as a 64-bit executable.)
1879 - gdbserver uses the new noack protocol mode for TCP connections to
1880 reduce communications latency, if also supported and enabled in GDB.
1882 - Support for the sparc64-linux-gnu target is now included in
1885 - The amd64-linux build of gdbserver now supports debugging both
1886 32-bit and 64-bit programs.
1888 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1889 now support hardware watchpoints, and will use them automatically
1894 GDB now has support for scripting using Python. Whether this is
1895 available is determined at configure time.
1897 New GDB commands can now be written in Python.
1899 * Ada tasking support
1901 Ada tasks can now be inspected in GDB. The following commands have
1905 Print the list of Ada tasks.
1907 Print detailed information about task number N.
1909 Print the task number of the current task.
1911 Switch the context of debugging to task number N.
1913 * Support for user-defined prefixed commands. The "define" command can
1914 add new commands to existing prefixes, e.g. "target".
1916 * Multi-inferior, multi-process debugging.
1918 GDB now has generalized support for multi-inferior debugging. See
1919 "Debugging Multiple Inferiors" in the manual for more information.
1920 Although availability still depends on target support, the command
1921 set is more uniform now. The GNU/Linux specific multi-forks support
1922 has been migrated to this new framework. This implied some user
1923 visible changes; see "New commands" and also "Removed commands"
1926 * Target descriptions can now describe the target OS ABI. See the
1927 "Target Description Format" section in the user manual for more
1930 * Target descriptions can now describe "compatible" architectures
1931 to indicate that the target can execute applications for a different
1932 architecture in addition to those for the main target architecture.
1933 See the "Target Description Format" section in the user manual for
1936 * Multi-architecture debugging.
1938 GDB now includes general supports for debugging applications on
1939 hybrid systems that use more than one single processor architecture
1940 at the same time. Each such hybrid architecture still requires
1941 specific support to be added. The only hybrid architecture supported
1942 in this version of GDB is the Cell Broadband Engine.
1944 * GDB now supports integrated debugging of Cell/B.E. applications that
1945 use both the PPU and SPU architectures. To enable support for hybrid
1946 Cell/B.E. debugging, you need to configure GDB to support both the
1947 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1948 --enable-targets configure option.
1950 * Non-stop mode debugging.
1952 For some targets, GDB now supports an optional mode of operation in
1953 which you can examine stopped threads while other threads continue
1954 to execute freely. This is referred to as non-stop mode, with the
1955 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1956 section in the user manual for more information.
1958 To be able to support remote non-stop debugging, a remote stub needs
1959 to implement the non-stop mode remote protocol extensions, as
1960 described in the "Remote Non-Stop" section of the user manual. The
1961 GDB remote stub, gdbserver, has been adjusted to support these
1962 extensions on linux targets.
1964 * New commands (for set/show, see "New options" below)
1966 catch syscall [NAME(S) | NUMBER(S)]
1967 Catch system calls. Arguments, which should be names of system
1968 calls or their numbers, mean catch only those syscalls. Without
1969 arguments, every syscall will be caught. When the inferior issues
1970 any of the specified syscalls, GDB will stop and announce the system
1971 call, both when it is called and when its call returns. This
1972 feature is currently available with a native GDB running on the
1973 Linux Kernel, under the following architectures: x86, x86_64,
1974 PowerPC and PowerPC64.
1976 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1978 Search memory for a sequence of bytes.
1980 maint set python print-stack
1981 maint show python print-stack
1982 Show a stack trace when an error is encountered in a Python script.
1985 Invoke CODE by passing it to the Python interpreter.
1990 These allow macros to be defined, undefined, and listed
1994 Show operating system information about processes.
1997 List the inferiors currently under GDB's control.
2000 Switch focus to inferior number NUM.
2003 Detach from inferior number NUM.
2006 Kill inferior number NUM.
2010 set spu stop-on-load
2011 show spu stop-on-load
2012 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2014 set spu auto-flush-cache
2015 show spu auto-flush-cache
2016 Control whether to automatically flush the software-managed cache
2017 during Cell/B.E. debugging.
2019 set sh calling-convention
2020 show sh calling-convention
2021 Control the calling convention used when calling SH target functions.
2024 show debug timestamp
2025 Control display of timestamps with GDB debugging output.
2027 set disassemble-next-line
2028 show disassemble-next-line
2029 Control display of disassembled source lines or instructions when
2032 set remote noack-packet
2033 show remote noack-packet
2034 Set/show the use of remote protocol QStartNoAckMode packet. See above
2035 under "New remote packets."
2037 set remote query-attached-packet
2038 show remote query-attached-packet
2039 Control use of remote protocol `qAttached' (query-attached) packet.
2041 set remote read-siginfo-object
2042 show remote read-siginfo-object
2043 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2046 set remote write-siginfo-object
2047 show remote write-siginfo-object
2048 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2051 set remote reverse-continue
2052 show remote reverse-continue
2053 Control use of remote protocol 'bc' (reverse-continue) packet.
2055 set remote reverse-step
2056 show remote reverse-step
2057 Control use of remote protocol 'bs' (reverse-step) packet.
2059 set displaced-stepping
2060 show displaced-stepping
2061 Control displaced stepping mode. Displaced stepping is a way to
2062 single-step over breakpoints without removing them from the debuggee.
2063 Also known as "out-of-line single-stepping".
2066 show debug displaced
2067 Control display of debugging info for displaced stepping.
2069 maint set internal-error
2070 maint show internal-error
2071 Control what GDB does when an internal error is detected.
2073 maint set internal-warning
2074 maint show internal-warning
2075 Control what GDB does when an internal warning is detected.
2080 Use a wrapper program to launch programs for debugging.
2082 set multiple-symbols (all|ask|cancel)
2083 show multiple-symbols
2084 The value of this variable can be changed to adjust the debugger behavior
2085 when an expression or a breakpoint location contains an ambiguous symbol
2086 name (an overloaded function name, for instance).
2088 set breakpoint always-inserted
2089 show breakpoint always-inserted
2090 Keep breakpoints always inserted in the target, as opposed to inserting
2091 them when resuming the target, and removing them when the target stops.
2092 This option can improve debugger performance on slow remote targets.
2094 set arm fallback-mode (arm|thumb|auto)
2095 show arm fallback-mode
2096 set arm force-mode (arm|thumb|auto)
2098 These commands control how ARM GDB determines whether instructions
2099 are ARM or Thumb. The default for both settings is auto, which uses
2100 the current CPSR value for instructions without symbols; previous
2101 versions of GDB behaved as if "set arm fallback-mode arm".
2103 set disable-randomization
2104 show disable-randomization
2105 Standalone programs run with the virtual address space randomization enabled
2106 by default on some platforms. This option keeps the addresses stable across
2107 multiple debugging sessions.
2111 Control whether other threads are stopped or not when some thread hits
2116 Requests that asynchronous execution is enabled in the target, if available.
2117 In this case, it's possible to resume target in the background, and interact
2118 with GDB while the target is running. "show target-async" displays the
2119 current state of asynchronous execution of the target.
2121 set target-wide-charset
2122 show target-wide-charset
2123 The target-wide-charset is the name of the character set that GDB
2124 uses when printing characters whose type is wchar_t.
2126 set tcp auto-retry (on|off)
2128 set tcp connect-timeout
2129 show tcp connect-timeout
2130 These commands allow GDB to retry failed TCP connections to a remote stub
2131 with a specified timeout period; this is useful if the stub is launched
2132 in parallel with GDB but may not be ready to accept connections immediately.
2134 set libthread-db-search-path
2135 show libthread-db-search-path
2136 Control list of directories which GDB will search for appropriate
2139 set schedule-multiple (on|off)
2140 show schedule-multiple
2141 Allow GDB to resume all threads of all processes or only threads of
2142 the current process.
2146 Use more aggressive caching for accesses to the stack. This improves
2147 performance of remote debugging (particularly backtraces) without
2148 affecting correctness.
2150 set interactive-mode (on|off|auto)
2151 show interactive-mode
2152 Control whether GDB runs in interactive mode (on) or not (off).
2153 When in interactive mode, GDB waits for the user to answer all
2154 queries. Otherwise, GDB does not wait and assumes the default
2155 answer. When set to auto (the default), GDB determines which
2156 mode to use based on the stdin settings.
2161 For program forks, this is replaced by the new more generic `info
2162 inferiors' command. To list checkpoints, you can still use the
2163 `info checkpoints' command, which was an alias for the `info forks'
2167 Replaced by the new `inferior' command. To switch between
2168 checkpoints, you can still use the `restart' command, which was an
2169 alias for the `fork' command.
2172 This is removed, since some targets don't have a notion of
2173 processes. To switch between processes, you can still use the
2174 `inferior' command using GDB's own inferior number.
2177 For program forks, this is replaced by the new more generic `kill
2178 inferior' command. To delete a checkpoint, you can still use the
2179 `delete checkpoint' command, which was an alias for the `delete
2183 For program forks, this is replaced by the new more generic `detach
2184 inferior' command. To detach a checkpoint, you can still use the
2185 `detach checkpoint' command, which was an alias for the `detach
2188 * New native configurations
2190 x86/x86_64 Darwin i[34567]86-*-darwin*
2192 x86_64 MinGW x86_64-*-mingw*
2196 Lattice Mico32 lm32-*
2197 x86 DICOS i[34567]86-*-dicos*
2198 x86_64 DICOS x86_64-*-dicos*
2201 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2202 (mingw32ce) debugging.
2208 These commands were actually not implemented on any target.
2210 *** Changes in GDB 6.8
2212 * New native configurations
2214 NetBSD/hppa hppa*-*netbsd*
2215 Xtensa GNU/Linux xtensa*-*-linux*
2219 NetBSD/hppa hppa*-*-netbsd*
2220 Xtensa GNU/Lunux xtensa*-*-linux*
2222 * Change in command line behavior -- corefiles vs. process ids.
2224 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2225 attaching to process NUMBER fails, GDB no longer attempts to open a
2226 core file named NUMBER. Attaching to a program using the -c option
2227 is no longer supported. Instead, use the '-p' or '--pid' options.
2229 * GDB can now be built as a native debugger for debugging Windows x86
2230 (mingw32) Portable Executable (PE) programs.
2232 * Pending breakpoints no longer change their number when their address
2235 * GDB now supports breakpoints with multiple locations,
2236 including breakpoints on C++ constructors, inside C++ templates,
2237 and in inlined functions.
2239 * GDB's ability to debug optimized code has been improved. GDB more
2240 accurately identifies function bodies and lexical blocks that occupy
2241 more than one contiguous range of addresses.
2243 * Target descriptions can now describe registers for PowerPC.
2245 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2246 registers on PowerPC targets.
2248 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2249 targets even when the libthread_db library is not available.
2251 * The GDB remote stub, gdbserver, now supports the new file transfer
2252 commands (remote put, remote get, and remote delete).
2254 * The GDB remote stub, gdbserver, now supports run and attach in
2255 extended-remote mode.
2257 * hppa*64*-*-hpux11* target broken
2258 The debugger is unable to start a program and fails with the following
2259 error: "Error trying to get information about dynamic linker".
2260 The gdb-6.7 release is also affected.
2262 * GDB now supports the --enable-targets= configure option to allow
2263 building a single GDB executable that supports multiple remote
2264 target architectures.
2266 * GDB now supports debugging C and C++ programs which use the
2267 Decimal Floating Point extension. In addition, the PowerPC target
2268 now has a set of pseudo-registers to inspect decimal float values
2269 stored in two consecutive float registers.
2271 * The -break-insert MI command can optionally create pending
2274 * Improved support for debugging Ada
2275 Many improvements to the Ada language support have been made. These
2277 - Better support for Ada2005 interface types
2278 - Improved handling of arrays and slices in general
2279 - Better support for Taft-amendment types
2280 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2282 - Improved command completion in Ada
2285 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2290 set print frame-arguments (all|scalars|none)
2291 show print frame-arguments
2292 The value of this variable can be changed to control which argument
2293 values should be printed by the debugger when displaying a frame.
2298 Transfer files to and from a remote target, and delete remote files.
2305 Transfer files to and from a remote target, and delete remote files.
2307 * New remote packets
2314 Open, close, read, write, and delete files on the remote system.
2317 Attach to an existing process on the remote system, in extended-remote
2321 Run a new process on the remote system, in extended-remote mode.
2323 *** Changes in GDB 6.7
2325 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2326 bfd, libiberty and opcodes, as revealed by static analysis donated by
2327 Coverity, Inc. (http://scan.coverity.com).
2329 * When looking up multiply-defined global symbols, GDB will now prefer the
2330 symbol definition in the current shared library if it was built using the
2331 -Bsymbolic linker option.
2333 * When the Text User Interface (TUI) is not configured, GDB will now
2334 recognize the -tui command-line option and print a message that the TUI
2337 * The GDB remote stub, gdbserver, now has lower overhead for high
2338 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2340 * GDB for MIPS targets now autodetects whether a remote target provides
2341 32-bit or 64-bit register values.
2343 * Support for C++ member pointers has been improved.
2345 * GDB now understands XML target descriptions, which specify the
2346 target's overall architecture. GDB can read a description from
2347 a local file or over the remote serial protocol.
2349 * Vectors of single-byte data use a new integer type which is not
2350 automatically displayed as character or string data.
2352 * The /s format now works with the print command. It displays
2353 arrays of single-byte integers and pointers to single-byte integers
2356 * Target descriptions can now describe target-specific registers,
2357 for architectures which have implemented the support (currently
2358 only ARM, M68K, and MIPS).
2360 * GDB and the GDB remote stub, gdbserver, now support the XScale
2363 * The GDB remote stub, gdbserver, has been updated to support
2364 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2365 has been rewritten to use the standard GDB remote protocol.
2367 * GDB can now step into C++ functions which are called through thunks.
2369 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2371 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2372 layout. It also supports a TextSeg= and DataSeg= response when only
2373 segment base addresses (rather than offsets) are available.
2375 * The /i format now outputs any trailing branch delay slot instructions
2376 immediately following the last instruction within the count specified.
2378 * The GDB remote protocol "T" stop reply packet now supports a
2379 "library" response. Combined with the new "qXfer:libraries:read"
2380 packet, this response allows GDB to debug shared libraries on targets
2381 where the operating system manages the list of loaded libraries (e.g.
2382 Windows and SymbianOS).
2384 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2385 (DLLs) on Windows and Windows CE targets.
2387 * GDB now supports a faster verification that a .debug file matches its binary
2388 according to its build-id signature, if the signature is present.
2394 Enable or disable hardware flow control (RTS/CTS) on the serial port
2395 when debugging using remote targets.
2397 set mem inaccessible-by-default
2398 show mem inaccessible-by-default
2399 If the target supplies a memory map, for instance via the remote
2400 protocol's "qXfer:memory-map:read" packet, setting this variable
2401 prevents GDB from accessing memory outside the memory map. This
2402 is useful for targets with memory mapped registers or which react
2403 badly to accesses of unmapped address space.
2405 set breakpoint auto-hw
2406 show breakpoint auto-hw
2407 If the target supplies a memory map, for instance via the remote
2408 protocol's "qXfer:memory-map:read" packet, setting this variable
2409 lets GDB use hardware breakpoints automatically for memory regions
2410 where it can not use software breakpoints. This covers both the
2411 "break" command and internal breakpoints used for other commands
2412 including "next" and "finish".
2415 catch exception unhandled
2416 Stop the program execution when Ada exceptions are raised.
2419 Stop the program execution when an Ada assertion failed.
2423 Set an alternate system root for target files. This is a more
2424 general version of "set solib-absolute-prefix", which is now
2425 an alias to "set sysroot".
2428 Provide extended SPU facility status information. This set of
2429 commands is available only when debugging the Cell/B.E. SPU
2432 * New native configurations
2434 OpenBSD/sh sh*-*openbsd*
2437 unset tdesc filename
2439 Use the specified local file as an XML target description, and do
2440 not query the target for its built-in description.
2444 OpenBSD/sh sh*-*-openbsd*
2445 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2446 Toshiba Media Processor mep-elf
2448 * New remote packets
2451 Ignore the specified signals; pass them directly to the debugged program
2452 without stopping other threads or reporting them to GDB.
2454 qXfer:features:read:
2455 Read an XML target description from the target, which describes its
2460 Read or write contents of an spufs file on the target system. These
2461 packets are available only on the Cell/B.E. SPU architecture.
2463 qXfer:libraries:read:
2464 Report the loaded shared libraries. Combined with new "T" packet
2465 response, this packet allows GDB to debug shared libraries on
2466 targets where the operating system manages the list of loaded
2467 libraries (e.g. Windows and SymbianOS).
2471 Support for these obsolete configurations has been removed.
2479 i[34567]86-*-lynxos*
2480 i[34567]86-*-netware*
2481 i[34567]86-*-sco3.2v5*
2482 i[34567]86-*-sco3.2v4*
2484 i[34567]86-*-sysv4.2*
2487 i[34567]86-*-unixware2*
2488 i[34567]86-*-unixware*
2497 * Other removed features
2504 Various m68k-only ROM monitors.
2511 Various Renesas ROM monitors and debugging interfaces for SH and
2516 Support for a Macraigor serial interface to on-chip debugging.
2517 GDB does not directly support the newer parallel or USB
2522 A debug information format. The predecessor to DWARF 2 and
2523 DWARF 3, which are still supported.
2525 Support for the HP aCC compiler on HP-UX/PA-RISC
2527 SOM-encapsulated symbolic debugging information, automatic
2528 invocation of pxdb, and the aCC custom C++ ABI. This does not
2529 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2530 with aCC can still be debugged on an assembly level.
2532 MIPS ".pdr" sections
2534 A MIPS-specific format used to describe stack frame layout
2535 in debugging information.
2539 GDB could work with an older version of Guile to debug
2540 the interpreter and Scheme programs running in it.
2542 set mips stack-arg-size
2543 set mips saved-gpreg-size
2545 Use "set mips abi" to control parameter passing for MIPS.
2547 *** Changes in GDB 6.6
2552 Cell Broadband Engine SPU spu-elf
2554 * GDB can now be configured as a cross-debugger targeting native Windows
2555 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2556 running on a Windows system over TCP/IP to debug Windows programs.
2558 * The GDB remote stub, gdbserver, has been updated to support Windows and
2559 Cygwin debugging. Both single-threaded and multi-threaded programs are
2562 * The "set trust-readonly-sections" command works again. This command was
2563 broken in GDB 6.3, 6.4, and 6.5.
2565 * The "load" command now supports writing to flash memory, if the remote
2566 stub provides the required support.
2568 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2569 longer requires symbolic debug information (e.g. DWARF-2).
2574 unset substitute-path
2575 show substitute-path
2576 Manage a list of substitution rules that GDB uses to rewrite the name
2577 of the directories where the sources are located. This can be useful
2578 for instance when the sources were moved to a different location
2579 between compilation and debugging.
2583 Print each CLI command as it is executed. Each command is prefixed with
2584 a number of `+' symbols representing the nesting depth.
2585 The source command now has a `-v' option to enable the same feature.
2589 The ARM Demon monitor support (RDP protocol, "target rdp").
2591 Kernel Object Display, an embedded debugging feature which only worked with
2592 an obsolete version of Cisco IOS.
2594 The 'set download-write-size' and 'show download-write-size' commands.
2596 * New remote packets
2599 Tell a stub about GDB client features, and request remote target features.
2600 The first feature implemented is PacketSize, which allows the target to
2601 specify the size of packets it can handle - to minimize the number of
2602 packets required and improve performance when connected to a remote
2606 Fetch an OS auxilliary vector from the remote stub. This packet is a
2607 more efficient replacement for qPart:auxv:read.
2609 qXfer:memory-map:read:
2610 Fetch a memory map from the remote stub, including information about
2611 RAM, ROM, and flash memory devices.
2616 Erase and program a flash memory device.
2618 * Removed remote packets
2621 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2622 used it, and only gdbserver implemented it.
2624 *** Changes in GDB 6.5
2628 Renesas M32C/M16C m32c-elf
2630 Morpho Technologies ms1 ms1-elf
2634 init-if-undefined Initialize a convenience variable, but
2635 only if it doesn't already have a value.
2637 The following commands are presently only implemented for native GNU/Linux:
2639 checkpoint Save a snapshot of the program state.
2641 restart <n> Return the program state to a
2642 previously saved state.
2644 info checkpoints List currently saved checkpoints.
2646 delete-checkpoint <n> Delete a previously saved checkpoint.
2648 set|show detach-on-fork Tell gdb whether to detach from a newly
2649 forked process, or to keep debugging it.
2651 info forks List forks of the user program that
2652 are available to be debugged.
2654 fork <n> Switch to debugging one of several
2655 forks of the user program that are
2656 available to be debugged.
2658 delete-fork <n> Delete a fork from the list of forks
2659 that are available to be debugged (and
2660 kill the forked process).
2662 detach-fork <n> Delete a fork from the list of forks
2663 that are available to be debugged (and
2664 allow the process to continue).
2668 Morpho Technologies ms2 ms1-elf
2670 * Improved Windows host support
2672 GDB now builds as a cross debugger hosted on i686-mingw32, including
2673 native console support, and remote communications using either
2674 network sockets or serial ports.
2676 * Improved Modula-2 language support
2678 GDB can now print most types in the Modula-2 syntax. This includes:
2679 basic types, set types, record types, enumerated types, range types,
2680 pointer types and ARRAY types. Procedure var parameters are correctly
2681 printed and hexadecimal addresses and character constants are also
2682 written in the Modula-2 syntax. Best results can be obtained by using
2683 GNU Modula-2 together with the -gdwarf-2 command line option.
2687 The ARM rdi-share module.
2689 The Netware NLM debug server.
2691 *** Changes in GDB 6.4
2693 * New native configurations
2695 OpenBSD/arm arm*-*-openbsd*
2696 OpenBSD/mips64 mips64-*-openbsd*
2700 Morpho Technologies ms1 ms1-elf
2702 * New command line options
2704 --batch-silent As for --batch, but totally silent.
2705 --return-child-result The debugger will exist with the same value
2706 the child (debugged) program exited with.
2707 --eval-command COMMAND, -ex COMMAND
2708 Execute a single GDB CLI command. This may be
2709 specified multiple times and in conjunction
2710 with the --command (-x) option.
2712 * Deprecated commands removed
2714 The following commands, that were deprecated in 2000, have been
2718 set|show arm disassembly-flavor set|show arm disassembler
2719 othernames set arm disassembler
2720 set|show remotedebug set|show debug remote
2721 set|show archdebug set|show debug arch
2722 set|show eventdebug set|show debug event
2725 * New BSD user-level threads support
2727 It is now possible to debug programs using the user-level threads
2728 library on OpenBSD and FreeBSD. Currently supported (target)
2731 FreeBSD/amd64 x86_64-*-freebsd*
2732 FreeBSD/i386 i386-*-freebsd*
2733 OpenBSD/i386 i386-*-openbsd*
2735 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2736 are not yet supported.
2738 * New support for Matsushita MN10300 w/sim added
2739 (Work in progress). mn10300-elf.
2741 * REMOVED configurations and files
2743 VxWorks and the XDR protocol *-*-vxworks
2744 Motorola MCORE mcore-*-*
2745 National Semiconductor NS32000 ns32k-*-*
2747 * New "set print array-indexes" command
2749 After turning this setting "on", GDB prints the index of each element
2750 when displaying arrays. The default is "off" to preserve the previous
2753 * VAX floating point support
2755 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2757 * User-defined command support
2759 In addition to using $arg0..$arg9 for argument passing, it is now possible
2760 to use $argc to determine now many arguments have been passed. See the
2761 section on user-defined commands in the user manual for more information.
2763 *** Changes in GDB 6.3:
2765 * New command line option
2767 GDB now accepts -l followed by a number to set the timeout for remote
2770 * GDB works with GCC -feliminate-dwarf2-dups
2772 GDB now supports a more compact representation of DWARF-2 debug
2773 information using DW_FORM_ref_addr references. These are produced
2774 by GCC with the option -feliminate-dwarf2-dups and also by some
2775 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2776 to use -feliminate-dwarf2-dups.
2778 * Internationalization
2780 When supported by the host system, GDB will be built with
2781 internationalization (libintl). The task of marking up the sources is
2782 continued, we're looking forward to our first translation.
2786 Initial support for debugging programs compiled with the GNAT
2787 implementation of the Ada programming language has been integrated
2788 into GDB. In this release, support is limited to expression evaluation.
2790 * New native configurations
2792 GNU/Linux/m32r m32r-*-linux-gnu
2796 GDB's remote protocol now includes support for the 'p' packet. This
2797 packet is used to fetch individual registers from a remote inferior.
2799 * END-OF-LIFE registers[] compatibility module
2801 GDB's internal register infrastructure has been completely rewritten.
2802 The new infrastructure making possible the implementation of key new
2803 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2806 GDB 6.3 will be the last release to include the the registers[]
2807 compatibility module that allowed out-of-date configurations to
2808 continue to work. This change directly impacts the following
2818 powerpc bdm protocol
2820 Unless there is activity to revive these configurations, they will be
2821 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2823 * OBSOLETE configurations and files
2825 Configurations that have been declared obsolete in this release have
2826 been commented out. Unless there is activity to revive these
2827 configurations, the next release of GDB will have their sources
2828 permanently REMOVED.
2837 *** Changes in GDB 6.2.1:
2839 * MIPS `break main; run' gave an heuristic-fence-post warning
2841 When attempting to run even a simple program, a warning about
2842 heuristic-fence-post being hit would be reported. This problem has
2845 * MIPS IRIX 'long double' crashed GDB
2847 When examining a long double variable, GDB would get a segmentation
2848 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2849 IRIX long double values).
2853 A bug in the VAX stack code was causing problems with the "next"
2854 command. This problem has been fixed.
2856 *** Changes in GDB 6.2:
2858 * Fix for ``many threads''
2860 On GNU/Linux systems that use the NPTL threads library, a program
2861 rapidly creating and deleting threads would confuse GDB leading to the
2864 ptrace: No such process.
2865 thread_db_get_info: cannot get thread info: generic error
2867 This problem has been fixed.
2869 * "-async" and "-noasync" options removed.
2871 Support for the broken "-noasync" option has been removed (it caused
2874 * New ``start'' command.
2876 This command runs the program until the begining of the main procedure.
2878 * New BSD Kernel Data Access Library (libkvm) interface
2880 Using ``target kvm'' it is now possible to debug kernel core dumps and
2881 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2882 platforms. Currently supported (native-only) configurations are:
2884 FreeBSD/amd64 x86_64-*-freebsd*
2885 FreeBSD/i386 i?86-*-freebsd*
2886 NetBSD/i386 i?86-*-netbsd*
2887 NetBSD/m68k m68*-*-netbsd*
2888 NetBSD/sparc sparc-*-netbsd*
2889 OpenBSD/amd64 x86_64-*-openbsd*
2890 OpenBSD/i386 i?86-*-openbsd*
2891 OpenBSD/m68k m68*-openbsd*
2892 OpenBSD/sparc sparc-*-openbsd*
2894 * Signal trampoline code overhauled
2896 Many generic problems with GDB's signal handling code have been fixed.
2897 These include: backtraces through non-contiguous stacks; recognition
2898 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2899 call; backtrace through a signal trampoline; step into and out of
2900 signal handlers; and single-stepping in the signal trampoline.
2902 Please note that kernel bugs are a limiting factor here. These
2903 features have been shown to work on an s390 GNU/Linux system that
2904 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2906 * Cygwin support for DWARF 2 added.
2908 * New native configurations
2910 GNU/Linux/hppa hppa*-*-linux*
2911 OpenBSD/hppa hppa*-*-openbsd*
2912 OpenBSD/m68k m68*-*-openbsd*
2913 OpenBSD/m88k m88*-*-openbsd*
2914 OpenBSD/powerpc powerpc-*-openbsd*
2915 NetBSD/vax vax-*-netbsd*
2916 OpenBSD/vax vax-*-openbsd*
2918 * END-OF-LIFE frame compatibility module
2920 GDB's internal frame infrastructure has been completely rewritten.
2921 The new infrastructure making it possible to support key new features
2922 including DWARF 2 Call Frame Information. To aid in the task of
2923 migrating old configurations to this new infrastructure, a
2924 compatibility module, that allowed old configurations to continue to
2925 work, was also included.
2927 GDB 6.2 will be the last release to include this frame compatibility
2928 module. This change directly impacts the following configurations:
2938 Unless there is activity to revive these configurations, they will be
2939 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2941 * REMOVED configurations and files
2943 Sun 3, running SunOS 3 m68*-*-sunos3*
2944 Sun 3, running SunOS 4 m68*-*-sunos4*
2945 Sun 2, running SunOS 3 m68000-*-sunos3*
2946 Sun 2, running SunOS 4 m68000-*-sunos4*
2947 Motorola 680x0 running LynxOS m68*-*-lynxos*
2948 AT&T 3b1/Unix pc m68*-att-*
2949 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2950 decstation mips-dec-* mips-little-*
2951 riscos mips-*-riscos* mips-*-sysv*
2952 sonymips mips-sony-*
2953 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2955 *** Changes in GDB 6.1.1:
2957 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2959 The TUI (Text-mode User Interface) is now built as part of a default
2960 GDB configuration. It is enabled by either selecting the TUI with the
2961 command line option "-i=tui" or by running the separate "gdbtui"
2962 program. For more information on the TUI, see the manual "Debugging
2965 * Pending breakpoint support (also included in GDB 6.1)
2967 Support has been added to allow you to specify breakpoints in shared
2968 libraries that have not yet been loaded. If a breakpoint location
2969 cannot be found, and the "breakpoint pending" option is set to auto,
2970 GDB queries you if you wish to make the breakpoint pending on a future
2971 shared-library load. If and when GDB resolves the breakpoint symbol,
2972 the pending breakpoint is removed as one or more regular breakpoints
2975 Pending breakpoints are very useful for GCJ Java debugging.
2977 * Fixed ISO-C build problems
2979 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2980 non ISO-C code that stopped them being built using a more strict ISO-C
2981 compiler (e.g., IBM's C compiler).
2983 * Fixed build problem on IRIX 5
2985 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2986 wasn't able to compile compile on an IRIX 5 system.
2988 * Added execute permission to gdb/gdbserver/configure
2990 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2991 permission. This bug would cause configure to fail on a number of
2992 systems (Solaris, IRIX). Ref: server/519.
2994 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2996 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2997 has been updated to use constant array sizes.
2999 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3001 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3002 its generated DWARF Call Frame Info. This encoding was causing GDB to
3003 panic, that panic has been fixed. Ref: gdb/1628.
3005 * Fixed a problem when examining parameters in shared library code.
3007 When examining parameters in optimized shared library code generated
3008 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3009 not available''. GDB now correctly displays the variable's value.
3011 *** Changes in GDB 6.1:
3013 * Removed --with-mmalloc
3015 Support for the mmalloc memory manager has been removed, as it
3016 conflicted with the internal gdb byte cache.
3018 * Changes in AMD64 configurations
3020 The AMD64 target now includes the %cs and %ss registers. As a result
3021 the AMD64 remote protocol has changed; this affects the floating-point
3022 and SSE registers. If you rely on those registers for your debugging,
3023 you should upgrade gdbserver on the remote side.
3025 * Revised SPARC target
3027 The SPARC target has been completely revised, incorporating the
3028 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3029 support for LynxOS and SunOS 4 has been dropped. Calling functions
3030 from within GDB on operating systems with a non-executable stack
3031 (Solaris, OpenBSD) now works.
3035 GDB has a new C++ demangler which does a better job on the mangled
3036 names generated by current versions of g++. It also runs faster, so
3037 with this and other changes gdb should now start faster on large C++
3040 * DWARF 2 Location Expressions
3042 GDB support for location expressions has been extended to support function
3043 arguments and frame bases. Older versions of GDB could crash when they
3046 * C++ nested types and namespaces
3048 GDB's support for nested types and namespaces in C++ has been
3049 improved, especially if you use the DWARF 2 debugging format. (This
3050 is the default for recent versions of GCC on most platforms.)
3051 Specifically, if you have a class "Inner" defined within a class or
3052 namespace "Outer", then GDB realizes that the class's name is
3053 "Outer::Inner", not simply "Inner". This should greatly reduce the
3054 frequency of complaints about not finding RTTI symbols. In addition,
3055 if you are stopped at inside of a function defined within a namespace,
3056 GDB modifies its name lookup accordingly.
3058 * New native configurations
3060 NetBSD/amd64 x86_64-*-netbsd*
3061 OpenBSD/amd64 x86_64-*-openbsd*
3062 OpenBSD/alpha alpha*-*-openbsd*
3063 OpenBSD/sparc sparc-*-openbsd*
3064 OpenBSD/sparc64 sparc64-*-openbsd*
3066 * New debugging protocols
3068 M32R with SDI protocol m32r-*-elf*
3070 * "set prompt-escape-char" command deleted.
3072 The command "set prompt-escape-char" has been deleted. This command,
3073 and its very obscure effet on GDB's prompt, was never documented,
3074 tested, nor mentioned in the NEWS file.
3076 * OBSOLETE configurations and files
3078 Configurations that have been declared obsolete in this release have
3079 been commented out. Unless there is activity to revive these
3080 configurations, the next release of GDB will have their sources
3081 permanently REMOVED.
3083 Sun 3, running SunOS 3 m68*-*-sunos3*
3084 Sun 3, running SunOS 4 m68*-*-sunos4*
3085 Sun 2, running SunOS 3 m68000-*-sunos3*
3086 Sun 2, running SunOS 4 m68000-*-sunos4*
3087 Motorola 680x0 running LynxOS m68*-*-lynxos*
3088 AT&T 3b1/Unix pc m68*-att-*
3089 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3090 decstation mips-dec-* mips-little-*
3091 riscos mips-*-riscos* mips-*-sysv*
3092 sonymips mips-sony-*
3093 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3095 * REMOVED configurations and files
3097 SGI Irix-4.x mips-sgi-irix4 or iris4
3098 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3099 Z8000 simulator z8k-zilog-none or z8ksim
3100 Matsushita MN10200 w/simulator mn10200-*-*
3101 H8/500 simulator h8500-hitachi-hms or h8500hms
3102 HP/PA running BSD hppa*-*-bsd*
3103 HP/PA running OSF/1 hppa*-*-osf*
3104 HP/PA Pro target hppa*-*-pro*
3105 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3106 386BSD i[3456]86-*-bsd*
3107 Sequent family i[3456]86-sequent-sysv4*
3108 i[3456]86-sequent-sysv*
3109 i[3456]86-sequent-bsd*
3110 SPARC running LynxOS sparc-*-lynxos*
3111 SPARC running SunOS 4 sparc-*-sunos4*
3112 Tsqware Sparclet sparclet-*-*
3113 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3115 *** Changes in GDB 6.0:
3119 Support for debugging the Objective-C programming language has been
3120 integrated into GDB.
3122 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3124 DWARF 2's Call Frame Information makes available compiler generated
3125 information that more exactly describes the program's run-time stack.
3126 By using this information, GDB is able to provide more robust stack
3129 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3130 have been updated to use a new backtrace mechanism which includes
3131 DWARF 2 CFI support.
3135 GDB's remote protocol has been extended to include support for hosted
3136 file I/O (where the remote target uses GDB's file system). See GDB's
3137 remote protocol documentation for details.
3139 * All targets using the new architecture framework.
3141 All of GDB's targets have been updated to use the new internal
3142 architecture framework. The way is now open for future GDB releases
3143 to include cross-architecture native debugging support (i386 on amd64,
3146 * GNU/Linux's Thread Local Storage (TLS)
3148 GDB now includes support for for the GNU/Linux implementation of
3149 per-thread variables.
3151 * GNU/Linux's Native POSIX Thread Library (NPTL)
3153 GDB's thread code has been updated to work with either the new
3154 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3156 * Separate debug info.
3158 GDB, in conjunction with BINUTILS, now supports a mechanism for
3159 automatically loading debug information from a separate file. Instead
3160 of shipping full debug and non-debug versions of system libraries,
3161 system integrators can now instead ship just the stripped libraries
3162 and optional debug files.
3164 * DWARF 2 Location Expressions
3166 DWARF 2 Location Expressions allow the compiler to more completely
3167 describe the location of variables (even in optimized code) to the
3170 GDB now includes preliminary support for location expressions (support
3171 for DW_OP_piece is still missing).
3175 A number of long standing bugs that caused GDB to die while starting a
3176 Java application have been fixed. GDB's Java support is now
3177 considered "useable".
3179 * GNU/Linux support for fork, vfork, and exec.
3181 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3182 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3185 * GDB supports logging output to a file
3187 There are two new commands, "set logging" and "show logging", which can be
3188 used to capture GDB's output to a file.
3190 * The meaning of "detach" has changed for gdbserver
3192 The "detach" command will now resume the application, as documented. To
3193 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3196 * d10v, m68hc11 `regs' command deprecated
3198 The `info registers' command has been updated so that it displays the
3199 registers using a format identical to the old `regs' command.
3203 A new command, "maint set profile on/off", has been added. This command can
3204 be used to enable or disable profiling while running GDB, to profile a
3205 session or a set of commands. In addition there is a new configure switch,
3206 "--enable-profiling", which will cause GDB to be compiled with profiling
3207 data, for more informative profiling results.
3209 * Default MI syntax changed to "mi2".
3211 The default MI (machine interface) syntax, enabled by the command line
3212 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3213 "mi1", can be enabled by specifying the option "-i=mi1".
3215 Support for the original "mi0" syntax (included in GDB 5.0) has been
3218 Fix for gdb/192: removed extraneous space when displaying frame level.
3219 Fix for gdb/672: update changelist is now output in mi list format.
3220 Fix for gdb/702: a -var-assign that updates the value now shows up
3221 in a subsequent -var-update.
3223 * New native configurations.
3225 FreeBSD/amd64 x86_64-*-freebsd*
3227 * Multi-arched targets.
3229 HP/PA HPUX11 hppa*-*-hpux*
3230 Renesas M32R/D w/simulator m32r-*-elf*
3232 * OBSOLETE configurations and files
3234 Configurations that have been declared obsolete in this release have
3235 been commented out. Unless there is activity to revive these
3236 configurations, the next release of GDB will have their sources
3237 permanently REMOVED.
3239 Z8000 simulator z8k-zilog-none or z8ksim
3240 Matsushita MN10200 w/simulator mn10200-*-*
3241 H8/500 simulator h8500-hitachi-hms or h8500hms
3242 HP/PA running BSD hppa*-*-bsd*
3243 HP/PA running OSF/1 hppa*-*-osf*
3244 HP/PA Pro target hppa*-*-pro*
3245 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3246 Sequent family i[3456]86-sequent-sysv4*
3247 i[3456]86-sequent-sysv*
3248 i[3456]86-sequent-bsd*
3249 Tsqware Sparclet sparclet-*-*
3250 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3252 * REMOVED configurations and files
3255 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3256 IBM AIX PS/2 i[3456]86-*-aix
3257 i386 running Mach 3.0 i[3456]86-*-mach3*
3258 i386 running Mach i[3456]86-*-mach*
3259 i386 running OSF/1 i[3456]86-*osf1mk*
3260 HP/Apollo 68k Family m68*-apollo*-sysv*,
3262 m68*-hp-bsd*, m68*-hp-hpux*
3263 Argonaut Risc Chip (ARC) arc-*-*
3264 Mitsubishi D30V d30v-*-*
3265 Fujitsu FR30 fr30-*-elf*
3266 OS/9000 i[34]86-*-os9k
3267 I960 with MON960 i960-*-coff
3269 * MIPS $fp behavior changed
3271 The convenience variable $fp, for the MIPS, now consistently returns
3272 the address of the current frame's base. Previously, depending on the
3273 context, $fp could refer to either $sp or the current frame's base
3274 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3275 The GNU Source-Level Debugger''.
3277 *** Changes in GDB 5.3:
3279 * GNU/Linux shared library multi-threaded performance improved.
3281 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3282 `/proc', in preference to `ptrace' for memory reads. This may result
3283 in an improvement in the start-up time of multi-threaded, shared
3284 library applications when run under GDB. One GDB user writes: ``loads
3285 shared libs like mad''.
3287 * ``gdbserver'' now supports multi-threaded applications on some targets
3289 Support for debugging multi-threaded applications which use
3290 the GNU/Linux LinuxThreads package has been added for
3291 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3292 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3294 * GDB now supports C/C++ preprocessor macros.
3296 GDB now expands preprocessor macro invocations in C/C++ expressions,
3297 and provides various commands for showing macro definitions and how
3300 The new command `macro expand EXPRESSION' expands any macro
3301 invocations in expression, and shows the result.
3303 The new command `show macro MACRO-NAME' shows the definition of the
3304 macro named MACRO-NAME, and where it was defined.
3306 Most compilers don't include information about macros in the debugging
3307 information by default. In GCC 3.1, for example, you need to compile
3308 your program with the options `-gdwarf-2 -g3'. If the macro
3309 information is present in the executable, GDB will read it.
3311 * Multi-arched targets.
3313 DEC Alpha (partial) alpha*-*-*
3314 DEC VAX (partial) vax-*-*
3316 National Semiconductor NS32000 (partial) ns32k-*-*
3317 Motorola 68000 (partial) m68k-*-*
3318 Motorola MCORE mcore-*-*
3322 Fujitsu FRV architecture added by Red Hat frv*-*-*
3325 * New native configurations
3327 Alpha NetBSD alpha*-*-netbsd*
3328 SH NetBSD sh*-*-netbsdelf*
3329 MIPS NetBSD mips*-*-netbsd*
3330 UltraSPARC NetBSD sparc64-*-netbsd*
3332 * OBSOLETE configurations and files
3334 Configurations that have been declared obsolete in this release have
3335 been commented out. Unless there is activity to revive these
3336 configurations, the next release of GDB will have their sources
3337 permanently REMOVED.
3339 Mitsubishi D30V d30v-*-*
3340 OS/9000 i[34]86-*-os9k
3341 IBM AIX PS/2 i[3456]86-*-aix
3342 Fujitsu FR30 fr30-*-elf*
3343 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3344 Argonaut Risc Chip (ARC) arc-*-*
3345 i386 running Mach 3.0 i[3456]86-*-mach3*
3346 i386 running Mach i[3456]86-*-mach*
3347 i386 running OSF/1 i[3456]86-*osf1mk*
3348 HP/Apollo 68k Family m68*-apollo*-sysv*,
3350 m68*-hp-bsd*, m68*-hp-hpux*
3351 I960 with MON960 i960-*-coff
3353 * OBSOLETE languages
3355 CHILL, a Pascal like language used by telecommunications companies.
3357 * REMOVED configurations and files
3359 AMD 29k family via UDI a29k-amd-udi, udi29k
3360 A29K VxWorks a29k-*-vxworks
3361 AMD 29000 embedded, using EBMON a29k-none-none
3362 AMD 29000 embedded with COFF a29k-none-coff
3363 AMD 29000 embedded with a.out a29k-none-aout
3365 testsuite/gdb.hp/gdb.threads-hp/ directory
3367 * New command "set max-user-call-depth <nnn>"
3369 This command allows the user to limit the call depth of user-defined
3370 commands. The default is 1024.
3372 * Changes in FreeBSD/i386 native debugging.
3374 Support for the "generate-core-file" has been added.
3376 * New commands "dump", "append", and "restore".
3378 These commands allow data to be copied from target memory
3379 to a bfd-format or binary file (dump and append), and back
3380 from a file into memory (restore).
3382 * Improved "next/step" support on multi-processor Alpha Tru64.
3384 The previous single-step mechanism could cause unpredictable problems,
3385 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3386 of a software single-step mechanism prevents this.
3388 *** Changes in GDB 5.2.1:
3396 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3397 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3398 Fix, by Joel Brobecker imported from mainline.
3400 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3401 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3402 Fix, by Fred Fish, imported from mainline.
3404 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3405 Surprisingly enough, it works now.
3406 By Michal Ludvig, imported from mainline.
3408 i386 hardware watchpoint support:
3409 avoid misses on second run for some targets.
3410 By Pierre Muller, imported from mainline.
3412 *** Changes in GDB 5.2:
3414 * New command "set trust-readonly-sections on[off]".
3416 This command is a hint that tells gdb that read-only sections
3417 really are read-only (ie. that their contents will not change).
3418 In this mode, gdb will go to the object file rather than the
3419 target to read memory from read-only sections (such as ".text").
3420 This can be a significant performance improvement on some
3421 (notably embedded) targets.
3423 * New command "generate-core-file" (or "gcore").
3425 This new gdb command allows the user to drop a core file of the child
3426 process state at any time. So far it's been implemented only for
3427 GNU/Linux and Solaris, but should be relatively easily ported to other
3428 hosts. Argument is core file name (defaults to core.<pid>).
3430 * New command line option
3432 GDB now accepts --pid or -p followed by a process id.
3434 * Change in command line behavior -- corefiles vs. process ids.
3436 There is a subtle behavior in the way in which GDB handles
3437 command line arguments. The first non-flag argument is always
3438 a program to debug, but the second non-flag argument may either
3439 be a corefile or a process id. Previously, GDB would attempt to
3440 open the second argument as a corefile, and if that failed, would
3441 issue a superfluous error message and then attempt to attach it as
3442 a process. Now, if the second argument begins with a non-digit,
3443 it will be treated as a corefile. If it begins with a digit,
3444 GDB will attempt to attach it as a process, and if no such process
3445 is found, will then attempt to open it as a corefile.
3447 * Changes in ARM configurations.
3449 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3450 configuration is fully multi-arch.
3452 * New native configurations
3454 ARM NetBSD arm*-*-netbsd*
3455 x86 OpenBSD i[3456]86-*-openbsd*
3456 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3457 Sparc64 running FreeBSD sparc64-*-freebsd*
3461 Sanyo XStormy16 xstormy16-elf
3463 * OBSOLETE configurations and files
3465 Configurations that have been declared obsolete in this release have
3466 been commented out. Unless there is activity to revive these
3467 configurations, the next release of GDB will have their sources
3468 permanently REMOVED.
3470 AMD 29k family via UDI a29k-amd-udi, udi29k
3471 A29K VxWorks a29k-*-vxworks
3472 AMD 29000 embedded, using EBMON a29k-none-none
3473 AMD 29000 embedded with COFF a29k-none-coff
3474 AMD 29000 embedded with a.out a29k-none-aout
3476 testsuite/gdb.hp/gdb.threads-hp/ directory
3478 * REMOVED configurations and files
3480 TI TMS320C80 tic80-*-*
3482 PowerPC Solaris powerpcle-*-solaris*
3483 PowerPC Windows NT powerpcle-*-cygwin32
3484 PowerPC Netware powerpc-*-netware*
3485 Harris/CXUX m88k m88*-harris-cxux*
3486 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3487 ns32k-utek-sysv* ns32k-utek-*
3488 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3489 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3490 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3491 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3492 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3494 * Changes to command line processing
3496 The new `--args' feature can be used to specify command-line arguments
3497 for the inferior from gdb's command line.
3499 * Changes to key bindings
3501 There is a new `operate-and-get-next' function bound to `C-o'.
3503 *** Changes in GDB 5.1.1
3505 Fix compile problem on DJGPP.
3507 Fix a problem with floating-point registers on the i386 being
3510 Fix to stop GDB crashing on .debug_str debug info.
3512 Numerous documentation fixes.
3514 Numerous testsuite fixes.
3516 *** Changes in GDB 5.1:
3518 * New native configurations
3520 Alpha FreeBSD alpha*-*-freebsd*
3521 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3522 MIPS GNU/Linux mips*-*-linux*
3523 MIPS SGI Irix 6.x mips*-sgi-irix6*
3524 ia64 AIX ia64-*-aix*
3525 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3529 Motorola 68HC11 and 68HC12 m68hc11-elf
3531 UltraSparc running GNU/Linux sparc64-*-linux*
3533 * OBSOLETE configurations and files
3535 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3536 Harris/CXUX m88k m88*-harris-cxux*
3537 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3538 ns32k-utek-sysv* ns32k-utek-*
3539 TI TMS320C80 tic80-*-*
3541 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3542 PowerPC Solaris powerpcle-*-solaris*
3543 PowerPC Windows NT powerpcle-*-cygwin32
3544 PowerPC Netware powerpc-*-netware*
3545 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3546 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3547 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3548 Apple Macintosh (MPW) host N/A
3550 stuff.c (Program to stuff files into a specially prepared space in kdb)
3551 kdb-start.c (Main loop for the standalone kernel debugger)
3553 Configurations that have been declared obsolete in this release have
3554 been commented out. Unless there is activity to revive these
3555 configurations, the next release of GDB will have their sources
3556 permanently REMOVED.
3558 * REMOVED configurations and files
3560 Altos 3068 m68*-altos-*
3561 Convex c1-*-*, c2-*-*
3563 ARM RISCix arm-*-* (as host)
3567 * GDB has been converted to ISO C.
3569 GDB's source code has been converted to ISO C. In particular, the
3570 sources are fully protoized, and rely on standard headers being
3575 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3577 * The MI enabled by default.
3579 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3580 revised and enabled by default. Packages which use GDB as a debugging
3581 engine behind a UI or another front end are encouraged to switch to
3582 using the GDB/MI interface, instead of the old annotations interface
3583 which is now deprecated.
3585 * Support for debugging Pascal programs.
3587 GDB now includes support for debugging Pascal programs. The following
3588 main features are supported:
3590 - Pascal-specific data types such as sets;
3592 - automatic recognition of Pascal sources based on file-name
3595 - Pascal-style display of data types, variables, and functions;
3597 - a Pascal expression parser.
3599 However, some important features are not yet supported.
3601 - Pascal string operations are not supported at all;
3603 - there are some problems with boolean types;
3605 - Pascal type hexadecimal constants are not supported
3606 because they conflict with the internal variables format;
3608 - support for Pascal objects and classes is not full yet;
3610 - unlike Pascal, GDB is case-sensitive for symbol names.
3612 * Changes in completion.
3614 Commands such as `shell', `run' and `set args', which pass arguments
3615 to inferior programs, now complete on file names, similar to what
3616 users expect at the shell prompt.
3618 Commands which accept locations, such as `disassemble', `print',
3619 `breakpoint', `until', etc. now complete on filenames as well as
3620 program symbols. Thus, if you type "break foob TAB", and the source
3621 files linked into the programs include `foobar.c', that file name will
3622 be one of the candidates for completion. However, file names are not
3623 considered for completion after you typed a colon that delimits a file
3624 name from a name of a function in that file, as in "break foo.c:bar".
3626 `set demangle-style' completes on available demangling styles.
3628 * New platform-independent commands:
3630 It is now possible to define a post-hook for a command as well as a
3631 hook that runs before the command. For more details, see the
3632 documentation of `hookpost' in the GDB manual.
3634 * Changes in GNU/Linux native debugging.
3636 Support for debugging multi-threaded programs has been completely
3637 revised for all platforms except m68k and sparc. You can now debug as
3638 many threads as your system allows you to have.
3640 Attach/detach is supported for multi-threaded programs.
3642 Support for SSE registers was added for x86. This doesn't work for
3643 multi-threaded programs though.
3645 * Changes in MIPS configurations.
3647 Multi-arch support is enabled for all MIPS configurations.
3649 GDB can now be built as native debugger on SGI Irix 6.x systems for
3650 debugging n32 executables. (Debugging 64-bit executables is not yet
3653 * Unified support for hardware watchpoints in all x86 configurations.
3655 Most (if not all) native x86 configurations support hardware-assisted
3656 breakpoints and watchpoints in a unified manner. This support
3657 implements debug register sharing between watchpoints, which allows to
3658 put a virtually infinite number of watchpoints on the same address,
3659 and also supports watching regions up to 16 bytes with several debug
3662 The new maintenance command `maintenance show-debug-regs' toggles
3663 debugging print-outs in functions that insert, remove, and test
3664 watchpoints and hardware breakpoints.
3666 * Changes in the DJGPP native configuration.
3668 New command ``info dos sysinfo'' displays assorted information about
3669 the CPU, OS, memory, and DPMI server.
3671 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3672 display information about segment descriptors stored in GDT, LDT, and
3675 New commands ``info dos pde'' and ``info dos pte'' display entries
3676 from Page Directory and Page Tables (for now works with CWSDPMI only).
3677 New command ``info dos address-pte'' displays the Page Table entry for
3678 a given linear address.
3680 GDB can now pass command lines longer than 126 characters to the
3681 program being debugged (requires an update to the libdbg.a library
3682 which is part of the DJGPP development kit).
3684 DWARF2 debug info is now supported.
3686 It is now possible to `step' and `next' through calls to `longjmp'.
3688 * Changes in documentation.
3690 All GDB documentation was converted to GFDL, the GNU Free
3691 Documentation License.
3693 Tracepoints-related commands are now fully documented in the GDB
3696 TUI, the Text-mode User Interface, is now documented in the manual.
3698 Tracepoints-related commands are now fully documented in the GDB
3701 The "GDB Internals" manual now has an index. It also includes
3702 documentation of `ui_out' functions, GDB coding standards, x86
3703 hardware watchpoints, and memory region attributes.
3705 * GDB's version number moved to ``version.in''
3707 The Makefile variable VERSION has been replaced by the file
3708 ``version.in''. People creating GDB distributions should update the
3709 contents of this file.
3713 GUD support is now a standard part of the EMACS distribution.
3715 *** Changes in GDB 5.0:
3717 * Improved support for debugging FP programs on x86 targets
3719 Unified and much-improved support for debugging floating-point
3720 programs on all x86 targets. In particular, ``info float'' now
3721 displays the FP registers in the same format on all x86 targets, with
3722 greater level of detail.
3724 * Improvements and bugfixes in hardware-assisted watchpoints
3726 It is now possible to watch array elements, struct members, and
3727 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3728 on x86 targets no longer erroneously trigger when the address is
3731 * Improvements in the native DJGPP version of GDB
3733 The distribution now includes all the scripts and auxiliary files
3734 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3735 machines ``out of the box''.
3737 The DJGPP version can now debug programs that use signals. It is
3738 possible to catch signals that happened in the debuggee, deliver
3739 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3740 would kill the program being debugged.) Programs that hook hardware
3741 interrupts (keyboard, timer, etc.) can also be debugged.
3743 It is now possible to debug DJGPP programs that redirect their
3744 standard handles or switch them to raw (as opposed to cooked) mode, or
3745 even close them. The command ``run < foo > bar'' works as expected,
3746 and ``info terminal'' reports useful information about the debuggee's
3747 terminal, including raw/cooked mode, redirection, etc.
3749 The DJGPP version now uses termios functions for console I/O, which
3750 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3753 DOS-style file names with drive letters are now fully supported by
3756 It is now possible to debug DJGPP programs that switch their working
3757 directory. It is also possible to rerun the debuggee any number of
3758 times without restarting GDB; thus, you can use the same setup,
3759 breakpoints, etc. for many debugging sessions.
3761 * New native configurations
3763 ARM GNU/Linux arm*-*-linux*
3764 PowerPC GNU/Linux powerpc-*-linux*
3768 Motorola MCore mcore-*-*
3769 x86 VxWorks i[3456]86-*-vxworks*
3770 PowerPC VxWorks powerpc-*-vxworks*
3771 TI TMS320C80 tic80-*-*
3773 * OBSOLETE configurations
3775 Altos 3068 m68*-altos-*
3776 Convex c1-*-*, c2-*-*
3778 ARM RISCix arm-*-* (as host)
3781 Configurations that have been declared obsolete will be commented out,
3782 but the code will be left in place. If there is no activity to revive
3783 these configurations before the next release of GDB, the sources will
3784 be permanently REMOVED.
3786 * Gould support removed
3788 Support for the Gould PowerNode and NP1 has been removed.
3790 * New features for SVR4
3792 On SVR4 native platforms (such as Solaris), if you attach to a process
3793 without first loading a symbol file, GDB will now attempt to locate and
3794 load symbols from the running process's executable file.
3796 * Many C++ enhancements
3798 C++ support has been greatly improved. Overload resolution now works properly
3799 in almost all cases. RTTI support is on the way.
3801 * Remote targets can connect to a sub-program
3803 A popen(3) style serial-device has been added. This device starts a
3804 sub-process (such as a stand-alone simulator) and then communicates
3805 with that. The sub-program to run is specified using the syntax
3806 ``|<program> <args>'' vis:
3808 (gdb) set remotedebug 1
3809 (gdb) target extended-remote |mn10300-elf-sim program-args
3811 * MIPS 64 remote protocol
3813 A long standing bug in the mips64 remote protocol where by GDB
3814 expected certain 32 bit registers (ex SR) to be transfered as 32
3815 instead of 64 bits has been fixed.
3817 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3818 added to provide backward compatibility with older versions of GDB.
3820 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3822 The command ``set remotebinarydownload'' command has been replaced by
3823 ``set remote X-packet''. Other commands in ``set remote'' family
3824 include ``set remote P-packet''.
3826 * Breakpoint commands accept ranges.
3828 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3829 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3830 ``tracepoint passcount'' also accepts a range of tracepoints.
3832 * ``apropos'' command added.
3834 The ``apropos'' command searches through command names and
3835 documentation strings, printing out matches, making it much easier to
3836 try to find a command that does what you are looking for.
3840 A new machine oriented interface (MI) has been added to GDB. This
3841 interface is designed for debug environments running GDB as a separate
3842 process. This is part of the long term libGDB project. See the
3843 "GDB/MI" chapter of the GDB manual for further information. It can be
3844 enabled by configuring with:
3846 .../configure --enable-gdbmi
3848 *** Changes in GDB-4.18:
3850 * New native configurations
3852 HP-UX 10.20 hppa*-*-hpux10.20
3853 HP-UX 11.x hppa*-*-hpux11.0*
3854 M68K GNU/Linux m68*-*-linux*
3858 Fujitsu FR30 fr30-*-elf*
3859 Intel StrongARM strongarm-*-*
3860 Mitsubishi D30V d30v-*-*
3862 * OBSOLETE configurations
3864 Gould PowerNode, NP1 np1-*-*, pn-*-*
3866 Configurations that have been declared obsolete will be commented out,
3867 but the code will be left in place. If there is no activity to revive
3868 these configurations before the next release of GDB, the sources will
3869 be permanently REMOVED.
3873 As a compatibility experiment, GDB's source files buildsym.h and
3874 buildsym.c have been converted to pure standard C, no longer
3875 containing any K&R compatibility code. We believe that all systems in
3876 use today either come with a standard C compiler, or have a GCC port
3877 available. If this is not true, please report the affected
3878 configuration to bug-gdb@gnu.org immediately. See the README file for
3879 information about getting a standard C compiler if you don't have one
3884 GDB now uses readline 2.2.
3886 * set extension-language
3888 You can now control the mapping between filename extensions and source
3889 languages by using the `set extension-language' command. For instance,
3890 you can ask GDB to treat .c files as C++ by saying
3891 set extension-language .c c++
3892 The command `info extensions' lists all of the recognized extensions
3893 and their associated languages.
3895 * Setting processor type for PowerPC and RS/6000
3897 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3898 you can use the `set processor' command to specify what variant of the
3899 PowerPC family you are debugging. The command
3903 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3904 following PowerPC and RS6000 variants:
3906 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3907 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3909 403GC IBM PowerPC 403GC
3910 505 Motorola PowerPC 505
3911 860 Motorola PowerPC 860 or 850
3912 601 Motorola PowerPC 601
3913 602 Motorola PowerPC 602
3914 603 Motorola/IBM PowerPC 603 or 603e
3915 604 Motorola PowerPC 604 or 604e
3916 750 Motorola/IBM PowerPC 750 or 750
3918 At the moment, this command just tells GDB what to name the
3919 special-purpose processor registers. Since almost all the affected
3920 registers are inaccessible to user-level programs, this command is
3921 only useful for remote debugging in its present form.
3925 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3926 more extensive support for HP-UX. Added features include shared
3927 library support, kernel threads and hardware watchpoints for 11.00,
3928 support for HP's ANSI C and C++ compilers, and a compatibility mode
3929 for xdb and dbx commands.
3933 HP's donation includes the new concept of catchpoints, which is a
3934 generalization of the old catch command. On HP-UX, it is now possible
3935 to catch exec, fork, and vfork, as well as library loading.
3937 This means that the existing catch command has changed; its first
3938 argument now specifies the type of catch to be set up. See the
3939 output of "help catch" for a list of catchpoint types.
3941 * Debugging across forks
3943 On HP-UX, you can choose which process to debug when a fork() happens
3948 HP has donated a curses-based terminal user interface (TUI). To get
3949 it, build with --enable-tui. Although this can be enabled for any
3950 configuration, at present it only works for native HP debugging.
3952 * GDB remote protocol additions
3954 A new protocol packet 'X' that writes binary data is now available.
3955 Default behavior is to try 'X', then drop back to 'M' if the stub
3956 fails to respond. The settable variable `remotebinarydownload'
3957 allows explicit control over the use of 'X'.
3959 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3960 full 64-bit address. The command
3962 set remoteaddresssize 32
3964 can be used to revert to the old behaviour. For existing remote stubs
3965 the change should not be noticed, as the additional address information
3968 In order to assist in debugging stubs, you may use the maintenance
3969 command `packet' to send any text string to the stub. For instance,
3971 maint packet heythere
3973 sends the packet "$heythere#<checksum>". Note that it is very easy to
3974 disrupt a debugging session by sending the wrong packet at the wrong
3977 The compare-sections command allows you to compare section data on the
3978 target to what is in the executable file without uploading or
3979 downloading, by comparing CRC checksums.
3981 * Tracing can collect general expressions
3983 You may now collect general expressions at tracepoints. This requires
3984 further additions to the target-side stub; see tracepoint.c and
3985 doc/agentexpr.texi for further details.
3987 * mask-address variable for Mips
3989 For Mips targets, you may control the zeroing of the upper 32 bits of
3990 a 64-bit address by entering `set mask-address on'. This is mainly
3991 of interest to users of embedded R4xxx and R5xxx processors.
3993 * Higher serial baud rates
3995 GDB's serial code now allows you to specify baud rates 57600, 115200,
3996 230400, and 460800 baud. (Note that your host system may not be able
3997 to achieve all of these rates.)
4001 The i960 configuration now includes an initial implementation of a
4002 builtin simulator, contributed by Jim Wilson.
4005 *** Changes in GDB-4.17:
4007 * New native configurations
4009 Alpha GNU/Linux alpha*-*-linux*
4010 Unixware 2.x i[3456]86-unixware2*
4011 Irix 6.x mips*-sgi-irix6*
4012 PowerPC GNU/Linux powerpc-*-linux*
4013 PowerPC Solaris powerpcle-*-solaris*
4014 Sparc GNU/Linux sparc-*-linux*
4015 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4019 Argonaut Risc Chip (ARC) arc-*-*
4020 Hitachi H8/300S h8300*-*-*
4021 Matsushita MN10200 w/simulator mn10200-*-*
4022 Matsushita MN10300 w/simulator mn10300-*-*
4023 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4024 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4025 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4026 Mitsubishi D10V w/simulator d10v-*-*
4027 Mitsubishi M32R/D w/simulator m32r-*-elf*
4028 Tsqware Sparclet sparclet-*-*
4029 NEC V850 w/simulator v850-*-*
4031 * New debugging protocols
4033 ARM with RDI protocol arm*-*-*
4034 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4035 DDB and LSI variants of PMON protocol mips*-*-*
4036 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4037 PowerPC with SDS protocol powerpc{,le}-*-eabi
4038 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4042 All configurations can now understand and use the DWARF 2 debugging
4043 format. The choice is automatic, if the symbol file contains DWARF 2
4048 GDB now includes basic Java language support. This support is
4049 only useful with Java compilers that produce native machine code.
4051 * solib-absolute-prefix and solib-search-path
4053 For SunOS and SVR4 shared libraries, you may now set the prefix for
4054 loading absolute shared library symbol files, and the search path for
4055 locating non-absolute shared library symbol files.
4057 * Live range splitting
4059 GDB can now effectively debug code for which GCC has performed live
4060 range splitting as part of its optimization. See gdb/doc/LRS for
4061 more details on the expected format of the stabs information.
4065 GDB's support for the GNU Hurd, including thread debugging, has been
4066 updated to work with current versions of the Hurd.
4070 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4071 instruction set. ARM GDB automatically detects when Thumb
4072 instructions are in use, and adjusts disassembly and backtracing
4077 GDB's MIPS target configurations now handle the MIP16 16-bit
4082 GDB now includes support for overlays; if an executable has been
4083 linked such that multiple sections are based at the same address, GDB
4084 will decide which section to use for symbolic info. You can choose to
4085 control the decision manually, using overlay commands, or implement
4086 additional target-side support and use "overlay load-target" to bring
4087 in the overlay mapping. Do "help overlay" for more detail.
4091 The command "info symbol <address>" displays information about
4092 the symbol at the specified address.
4096 The standard remote protocol now includes an extension that allows
4097 asynchronous collection and display of trace data. This requires
4098 extensive support in the target-side debugging stub. Tracing mode
4099 includes a new interaction mode in GDB and new commands: see the
4100 file tracepoint.c for more details.
4104 Configurations for embedded MIPS now include a simulator contributed
4105 by Cygnus Solutions. The simulator supports the instruction sets
4106 of most MIPS variants.
4110 Sparc configurations may now include the ERC32 simulator contributed
4111 by the European Space Agency. The simulator is not built into
4112 Sparc targets by default; configure with --enable-sim to include it.
4116 For target configurations that may include multiple variants of a
4117 basic architecture (such as MIPS and SH), you may now set the
4118 architecture explicitly. "set arch" sets, "info arch" lists
4119 the possible architectures.
4121 *** Changes in GDB-4.16:
4123 * New native configurations
4125 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4126 M68K NetBSD m68k-*-netbsd*
4127 PowerPC AIX 4.x powerpc-*-aix*
4128 PowerPC MacOS powerpc-*-macos*
4129 PowerPC Windows NT powerpcle-*-cygwin32
4130 RS/6000 AIX 4.x rs6000-*-aix4*
4134 ARM with RDP protocol arm-*-*
4135 I960 with MON960 i960-*-coff
4136 MIPS VxWorks mips*-*-vxworks*
4137 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4138 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4140 Matra Sparclet sparclet-*-*
4144 The powerpc-eabi configuration now includes the PSIM simulator,
4145 contributed by Andrew Cagney, with assistance from Mike Meissner.
4146 PSIM is a very elaborate model of the PowerPC, including not only
4147 basic instruction set execution, but also details of execution unit
4148 performance and I/O hardware. See sim/ppc/README for more details.
4152 GDB now works with Solaris 2.5.
4154 * Windows 95/NT native
4156 GDB will now work as a native debugger on Windows 95 and Windows NT.
4157 To build it from source, you must use the "gnu-win32" environment,
4158 which uses a DLL to emulate enough of Unix to run the GNU tools.
4159 Further information, binaries, and sources are available at
4160 ftp.cygnus.com, under pub/gnu-win32.
4162 * dont-repeat command
4164 If a user-defined command includes the command `dont-repeat', then the
4165 command will not be repeated if the user just types return. This is
4166 useful if the command is time-consuming to run, so that accidental
4167 extra keystrokes don't run the same command many times.
4169 * Send break instead of ^C
4171 The standard remote protocol now includes an option to send a break
4172 rather than a ^C to the target in order to interrupt it. By default,
4173 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4175 * Remote protocol timeout
4177 The standard remote protocol includes a new variable `remotetimeout'
4178 that allows you to set the number of seconds before GDB gives up trying
4179 to read from the target. The default value is 2.
4181 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4183 By default GDB will automatically keep track of objects as they are
4184 loaded and unloaded by the dynamic linker. By using the command `set
4185 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4186 when shared library events occur, thus allowing you to set breakpoints
4187 in shared libraries which are explicitly loaded by the inferior.
4189 Note this feature does not work on hpux8. On hpux9 you must link
4190 /usr/lib/end.o into your program. This feature should work
4191 automatically on hpux10.
4193 * Irix 5.x hardware watchpoint support
4195 Irix 5 configurations now support the use of hardware watchpoints.
4197 * Mips protocol "SYN garbage limit"
4199 When debugging a Mips target using the `target mips' protocol, you
4200 may set the number of characters that GDB will ignore by setting
4201 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4202 every character. The default value is 1050.
4204 * Recording and replaying remote debug sessions
4206 If you set `remotelogfile' to the name of a file, gdb will write to it
4207 a recording of a remote debug session. This recording may then be
4208 replayed back to gdb using "gdbreplay". See gdbserver/README for
4209 details. This is useful when you have a problem with GDB while doing
4210 remote debugging; you can make a recording of the session and send it
4211 to someone else, who can then recreate the problem.
4213 * Speedups for remote debugging
4215 GDB includes speedups for downloading and stepping MIPS systems using
4216 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4217 and more efficient S-record downloading.
4219 * Memory use reductions and statistics collection
4221 GDB now uses less memory and reports statistics about memory usage.
4222 Try the `maint print statistics' command, for example.
4224 *** Changes in GDB-4.15:
4226 * Psymtabs for XCOFF
4228 The symbol reader for AIX GDB now uses partial symbol tables. This
4229 can greatly improve startup time, especially for large executables.
4231 * Remote targets use caching
4233 Remote targets now use a data cache to speed up communication with the
4234 remote side. The data cache could lead to incorrect results because
4235 it doesn't know about volatile variables, thus making it impossible to
4236 debug targets which use memory mapped I/O devices. `set remotecache
4237 off' turns the the data cache off.
4239 * Remote targets may have threads
4241 The standard remote protocol now includes support for multiple threads
4242 in the target system, using new protocol commands 'H' and 'T'. See
4243 gdb/remote.c for details.
4247 If GDB is configured with `--enable-netrom', then it will include
4248 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4249 acts as though it is a bank of ROM on the target board, but you can
4250 write into it over the network. GDB's support consists only of
4251 support for fast loading into the emulated ROM; to debug, you must use
4252 another protocol, such as standard remote protocol. The usual
4253 sequence is something like
4255 target nrom <netrom-hostname>
4257 target remote <netrom-hostname>:1235
4261 GDB now includes support for the Apple Macintosh, as a host only. It
4262 may be run as either an MPW tool or as a standalone application, and
4263 it can debug through the serial port. All the usual GDB commands are
4264 available, but to the target command, you must supply "serial" as the
4265 device type instead of "/dev/ttyXX". See mpw-README in the main
4266 directory for more information on how to build. The MPW configuration
4267 scripts */mpw-config.in support only a few targets, and only the
4268 mips-idt-ecoff target has been tested.
4272 GDB configuration now uses autoconf. This is not user-visible,
4273 but does simplify configuration and building.
4277 GDB now supports hpux10.
4279 *** Changes in GDB-4.14:
4281 * New native configurations
4283 x86 FreeBSD i[345]86-*-freebsd
4284 x86 NetBSD i[345]86-*-netbsd
4285 NS32k NetBSD ns32k-*-netbsd
4286 Sparc NetBSD sparc-*-netbsd
4290 A29K VxWorks a29k-*-vxworks
4291 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4292 CPU32 EST-300 emulator m68*-*-est*
4293 PowerPC ELF powerpc-*-elf
4296 * Alpha OSF/1 support for procfs
4298 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4299 possible to attach to running processes. As the mounting of the /proc
4300 filesystem is optional on the Alpha, GDB automatically determines
4301 the availability of /proc during startup. This can lead to problems
4302 if /proc is unmounted after GDB has been started.
4304 * Arguments to user-defined commands
4306 User commands may accept up to 10 arguments separated by whitespace.
4307 Arguments are accessed within the user command via $arg0..$arg9. A
4310 print $arg0 + $arg1 + $arg2
4312 To execute the command use:
4315 Defines the command "adder" which prints the sum of its three arguments.
4316 Note the arguments are text substitutions, so they may reference variables,
4317 use complex expressions, or even perform inferior function calls.
4319 * New `if' and `while' commands
4321 This makes it possible to write more sophisticated user-defined
4322 commands. Both commands take a single argument, which is the
4323 expression to evaluate, and must be followed by the commands to
4324 execute, one per line, if the expression is nonzero, the list being
4325 terminated by the word `end'. The `if' command list may include an
4326 `else' word, which causes the following commands to be executed only
4327 if the expression is zero.
4329 * Fortran source language mode
4331 GDB now includes partial support for Fortran 77. It will recognize
4332 Fortran programs and can evaluate a subset of Fortran expressions, but
4333 variables and functions may not be handled correctly. GDB will work
4334 with G77, but does not yet know much about symbols emitted by other
4337 * Better HPUX support
4339 Most debugging facilities now work on dynamic executables for HPPAs
4340 running hpux9 or later. You can attach to running dynamically linked
4341 processes, but by default the dynamic libraries will be read-only, so
4342 for instance you won't be able to put breakpoints in them. To change
4343 that behavior do the following before running the program:
4349 This will cause the libraries to be mapped private and read-write.
4350 To revert to the normal behavior, do this:
4356 You cannot set breakpoints or examine data in the library until after
4357 the library is loaded if the function/data symbols do not have
4360 GDB can now also read debug symbols produced by the HP C compiler on
4361 HPPAs (sorry, no C++, Fortran or 68k support).
4363 * Target byte order now dynamically selectable
4365 You can choose which byte order to use with a target system, via the
4366 commands "set endian big" and "set endian little", and you can see the
4367 current setting by using "show endian". You can also give the command
4368 "set endian auto", in which case GDB will use the byte order
4369 associated with the executable. Currently, only embedded MIPS
4370 configurations support dynamic selection of target byte order.
4372 * New DOS host serial code
4374 This version uses DPMI interrupts to handle buffered I/O, so you
4375 no longer need to run asynctsr when debugging boards connected to
4378 *** Changes in GDB-4.13:
4380 * New "complete" command
4382 This lists all the possible completions for the rest of the line, if it
4383 were to be given as a command itself. This is intended for use by emacs.
4385 * Trailing space optional in prompt
4387 "set prompt" no longer adds a space for you after the prompt you set. This
4388 allows you to set a prompt which ends in a space or one that does not.
4390 * Breakpoint hit counts
4392 "info break" now displays a count of the number of times the breakpoint
4393 has been hit. This is especially useful in conjunction with "ignore"; you
4394 can ignore a large number of breakpoint hits, look at the breakpoint info
4395 to see how many times the breakpoint was hit, then run again, ignoring one
4396 less than that number, and this will get you quickly to the last hit of
4399 * Ability to stop printing at NULL character
4401 "set print null-stop" will cause GDB to stop printing the characters of
4402 an array when the first NULL is encountered. This is useful when large
4403 arrays actually contain only short strings.
4405 * Shared library breakpoints
4407 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4408 breakpoints in shared libraries before the executable is run.
4410 * Hardware watchpoints
4412 There is a new hardware breakpoint for the watch command for sparclite
4413 targets. See gdb/sparclite/hw_breakpoint.note.
4415 Hardware watchpoints are also now supported under GNU/Linux.
4419 Annotations have been added. These are for use with graphical interfaces,
4420 and are still experimental. Currently only gdba.el uses these.
4422 * Improved Irix 5 support
4424 GDB now works properly with Irix 5.2.
4426 * Improved HPPA support
4428 GDB now works properly with the latest GCC and GAS.
4430 * New native configurations
4432 Sequent PTX4 i[34]86-sequent-ptx4
4433 HPPA running OSF/1 hppa*-*-osf*
4434 Atari TT running SVR4 m68*-*-sysv4*
4435 RS/6000 LynxOS rs6000-*-lynxos*
4439 OS/9000 i[34]86-*-os9k
4440 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4443 * Hitachi SH7000 and E7000-PC ICE support
4445 There is now support for communicating with the Hitachi E7000-PC ICE.
4446 This is available automatically when GDB is configured for the SH.
4450 As usual, a variety of small fixes and improvements, both generic
4451 and configuration-specific. See the ChangeLog for more detail.
4453 *** Changes in GDB-4.12:
4455 * Irix 5 is now supported
4459 GDB-4.12 on the HPPA has a number of changes which make it unable
4460 to debug the output from the currently released versions of GCC and
4461 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4462 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4463 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4466 *** Changes in GDB-4.11:
4468 * User visible changes:
4472 The "set remotedebug" option is now consistent between the mips remote
4473 target, remote targets using the gdb-specific protocol, UDI (AMD's
4474 debug protocol for the 29k) and the 88k bug monitor. It is now an
4475 integer specifying a debug level (normally 0 or 1, but 2 means more
4476 debugging info for the mips target).
4478 * DEC Alpha native support
4480 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4481 debug info, but GDB works fairly well with the DEC compiler and should
4482 work with a future GCC release. See the README file for a few
4483 Alpha-specific notes.
4485 * Preliminary thread implementation
4487 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4489 * LynxOS native and target support for 386
4491 This release has been hosted on LynxOS 2.2, and also can be configured
4492 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4495 * Improvements in C++ mangling/demangling.
4497 This release has much better g++ debugging, specifically in name
4498 mangling/demangling, virtual function calls, print virtual table,
4499 call methods, ...etc.
4501 *** Changes in GDB-4.10:
4503 * User visible changes:
4505 Remote debugging using the GDB-specific (`target remote') protocol now
4506 supports the `load' command. This is only useful if you have some
4507 other way of getting the stub to the target system, and you can put it
4508 somewhere in memory where it won't get clobbered by the download.
4510 Filename completion now works.
4512 When run under emacs mode, the "info line" command now causes the
4513 arrow to point to the line specified. Also, "info line" prints
4514 addresses in symbolic form (as well as hex).
4516 All vxworks based targets now support a user settable option, called
4517 vxworks-timeout. This option represents the number of seconds gdb
4518 should wait for responses to rpc's. You might want to use this if
4519 your vxworks target is, perhaps, a slow software simulator or happens
4520 to be on the far side of a thin network line.
4524 This release contains support for using a DEC alpha as a GDB host for
4525 cross debugging. Native alpha debugging is not supported yet.
4528 *** Changes in GDB-4.9:
4532 This is the first GDB release which is accompanied by a matching testsuite.
4533 The testsuite requires installation of dejagnu, which should be available
4534 via ftp from most sites that carry GNU software.
4538 'Cfront' style demangling has had its name changed to 'ARM' style, to
4539 emphasize that it was written from the specifications in the C++ Annotated
4540 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4541 disclaimers, it still generated too much confusion with users attempting to
4542 use gdb with AT&T cfront.
4546 GDB now uses a standard remote interface to a simulator library.
4547 So far, the library contains simulators for the Zilog Z8001/2, the
4548 Hitachi H8/300, H8/500 and Super-H.
4550 * New targets supported
4552 H8/300 simulator h8300-hitachi-hms or h8300hms
4553 H8/500 simulator h8500-hitachi-hms or h8500hms
4554 SH simulator sh-hitachi-hms or sh
4555 Z8000 simulator z8k-zilog-none or z8ksim
4556 IDT MIPS board over serial line mips-idt-ecoff
4558 Cross-debugging to GO32 targets is supported. It requires a custom
4559 version of the i386-stub.c module which is integrated with the
4560 GO32 memory extender.
4562 * New remote protocols
4564 MIPS remote debugging protocol.
4566 * New source languages supported
4568 This version includes preliminary support for Chill, a Pascal like language
4569 used by telecommunications companies. Chill support is also being integrated
4570 into the GNU compiler, but we don't know when it will be publically available.
4573 *** Changes in GDB-4.8:
4575 * HP Precision Architecture supported
4577 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4578 version of this support was available as a set of patches from the
4579 University of Utah. GDB does not support debugging of programs
4580 compiled with the HP compiler, because HP will not document their file
4581 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4582 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4584 Many problems in the preliminary version have been fixed.
4586 * Faster and better demangling
4588 We have improved template demangling and fixed numerous bugs in the GNU style
4589 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4590 character types (wchar_t) are now supported. Demangling of each symbol is now
4591 only done once, and is cached when the symbol table for a file is read in.
4592 This results in a small increase in memory usage for C programs, a moderate
4593 increase in memory usage for C++ programs, and a fantastic speedup in
4596 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4597 from the specifications in the Annotated Reference Manual, which AT&T's
4598 compiler does not actually implement.
4600 * G++ multiple inheritance compiler problem
4602 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4603 inheritance lattices was reworked to properly discover ambiguities. We
4604 recently found an example which causes this new algorithm to fail in a
4605 very subtle way, producing bad debug information for those classes.
4606 The file 'gcc.patch' (in this directory) can be applied to gcc to
4607 circumvent the problem. A future GCC release will contain a complete
4610 The previous G++ debug info problem (mentioned below for the gdb-4.7
4611 release) is fixed in gcc version 2.3.2.
4613 * Improved configure script
4615 The `configure' script will now attempt to guess your system type if
4616 you don't supply a host system type. The old scheme of supplying a
4617 host system triplet is preferable over using this. All the magic is
4618 done in the new `config.guess' script. Examine it for details.
4620 We have also brought our configure script much more in line with the FSF's
4621 version. It now supports the --with-xxx options. In particular,
4622 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4623 The resulting GDB will not be able to read arbitrary object file formats --
4624 only the format ``expected'' to be used on the configured target system.
4625 We hope to make this the default in a future release.
4627 * Documentation improvements
4629 There's new internal documentation on how to modify GDB, and how to
4630 produce clean changes to the code. We implore people to read it
4631 before submitting changes.
4633 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4634 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4635 `info' files are also provided. To build `info' files from scratch,
4636 you will need the latest `makeinfo' release, which will be available in
4637 a future texinfo-X.Y release.
4639 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4640 We're not sure exactly which versions have this problem, but it has
4641 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4642 or better. If that isn't possible, there is a patch in
4643 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4644 around this problem.
4648 GDB now supports array constants that can be used in expressions typed in by
4649 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4650 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4653 The new directory `gdb/sparclite' contains a program that demonstrates
4654 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4656 * New native hosts supported
4658 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4659 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4661 * New targets supported
4663 AMD 29k family via UDI a29k-amd-udi or udi29k
4665 * New file formats supported
4667 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4668 HPUX core files, and SCO 3.2v2 core files.
4672 Attaching to processes now works again; thanks for the many bug reports.
4674 We have also stomped on a bunch of core dumps caused by
4675 printf_filtered("%s") problems.
4677 We eliminated a copyright problem on the rpc and ptrace header files
4678 for VxWorks, which was discovered at the last minute during the 4.7
4679 release. You should now be able to build a VxWorks GDB.
4681 You can now interrupt gdb while an attached process is running. This
4682 will cause the attached process to stop, and give control back to GDB.
4684 We fixed problems caused by using too many file descriptors
4685 for reading symbols from object files and libraries. This was
4686 especially a problem for programs that used many (~100) shared
4689 The `step' command now only enters a subroutine if there is line number
4690 information for the subroutine. Otherwise it acts like the `next'
4691 command. Previously, `step' would enter subroutines if there was
4692 any debugging information about the routine. This avoids problems
4693 when using `cc -g1' on MIPS machines.
4695 * Internal improvements
4697 GDB's internal interfaces have been improved to make it easier to support
4698 debugging of multiple languages in the future.
4700 GDB now uses a common structure for symbol information internally.
4701 Minimal symbols (derived from linkage symbols in object files), partial
4702 symbols (from a quick scan of debug information), and full symbols
4703 contain a common subset of information, making it easier to write
4704 shared code that handles any of them.
4706 * New command line options
4708 We now accept --silent as an alias for --quiet.
4712 The memory-mapped-malloc library is now licensed under the GNU Library
4713 General Public License.
4715 *** Changes in GDB-4.7:
4717 * Host/native/target split
4719 GDB has had some major internal surgery to untangle the support for
4720 hosts and remote targets. Now, when you configure GDB for a remote
4721 target, it will no longer load in all of the support for debugging
4722 local programs on the host. When fully completed and tested, this will
4723 ensure that arbitrary host/target combinations are possible.
4725 The primary conceptual shift is to separate the non-portable code in
4726 GDB into three categories. Host specific code is required any time GDB
4727 is compiled on that host, regardless of the target. Target specific
4728 code relates to the peculiarities of the target, but can be compiled on
4729 any host. Native specific code is everything else: it can only be
4730 built when the host and target are the same system. Child process
4731 handling and core file support are two common `native' examples.
4733 GDB's use of /proc for controlling Unix child processes is now cleaner.
4734 It has been split out into a single module under the `target_ops' vector,
4735 plus two native-dependent functions for each system that uses /proc.
4737 * New hosts supported
4739 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4740 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4741 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4743 * New targets supported
4745 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4746 68030 and CPU32 m68030-*-*, m68332-*-*
4748 * New native hosts supported
4750 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4751 (386bsd is not well tested yet)
4752 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4754 * New file formats supported
4756 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4757 supports reading of `a.out.adobe' object files, which are an a.out
4758 format extended with minimal information about multiple sections.
4762 `show copying' is the same as the old `info copying'.
4763 `show warranty' is the same as `info warrantee'.
4764 These were renamed for consistency. The old commands continue to work.
4766 `info handle' is a new alias for `info signals'.
4768 You can now define pre-command hooks, which attach arbitrary command
4769 scripts to any command. The commands in the hook will be executed
4770 prior to the user's command. You can also create a hook which will be
4771 executed whenever the program stops. See gdb.texinfo.
4775 We now deal with Cfront style name mangling, and can even extract type
4776 info from mangled symbols. GDB can automatically figure out which
4777 symbol mangling style your C++ compiler uses.
4779 Calling of methods and virtual functions has been improved as well.
4783 The crash that occured when debugging Sun Ansi-C compiled binaries is
4784 fixed. This was due to mishandling of the extra N_SO stabs output
4787 We also finally got Ultrix 4.2 running in house, and fixed core file
4788 support, with help from a dozen people on the net.
4790 John M. Farrell discovered that the reason that single-stepping was so
4791 slow on all of the Mips based platforms (primarily SGI and DEC) was
4792 that we were trying to demangle and lookup a symbol used for internal
4793 purposes on every instruction that was being stepped through. Changing
4794 the name of that symbol so that it couldn't be mistaken for a C++
4795 mangled symbol sped things up a great deal.
4797 Rich Pixley sped up symbol lookups in general by getting much smarter
4798 about when C++ symbol mangling is necessary. This should make symbol
4799 completion (TAB on the command line) much faster. It's not as fast as
4800 we'd like, but it's significantly faster than gdb-4.6.
4804 A new user controllable variable 'call_scratch_address' can
4805 specify the location of a scratch area to be used when GDB
4806 calls a function in the target. This is necessary because the
4807 usual method of putting the scratch area on the stack does not work
4808 in systems that have separate instruction and data spaces.
4810 We integrated changes to support the 29k UDI (Universal Debugger
4811 Interface), but discovered at the last minute that we didn't have all
4812 of the appropriate copyright paperwork. We are working with AMD to
4813 resolve this, and hope to have it available soon.
4817 We have sped up the remote serial line protocol, especially for targets
4818 with lots of registers. It now supports a new `expedited status' ('T')
4819 message which can be used in place of the existing 'S' status message.
4820 This allows the remote stub to send only the registers that GDB
4821 needs to make a quick decision about single-stepping or conditional
4822 breakpoints, eliminating the need to fetch the entire register set for
4823 each instruction being stepped through.
4825 The GDB remote serial protocol now implements a write-through cache for
4826 registers, only re-reading the registers if the target has run.
4828 There is also a new remote serial stub for SPARC processors. You can
4829 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4830 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4831 processor with a serial port.
4835 Configure.in files have become much easier to read and modify. A new
4836 `table driven' format makes it more obvious what configurations are
4837 supported, and what files each one uses.
4841 There is a new opcodes library which will eventually contain all of the
4842 disassembly routines and opcode tables. At present, it only contains
4843 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4844 disassembler (binutils/objdump) to share these routines.
4846 The libiberty library is now copylefted under the GNU Library General
4847 Public License. This allows more liberal use, and was done so libg++
4848 can use it. This makes no difference to GDB, since the Library License
4849 grants all the rights from the General Public License.
4853 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4854 reference to the stabs symbol info used by the debugger. It is (as far
4855 as we know) the only published document on this fascinating topic. We
4856 encourage you to read it, compare it to the stabs information on your
4857 system, and send improvements on the document in general (to
4858 bug-gdb@prep.ai.mit.edu).
4860 And, of course, many bugs have been fixed.
4863 *** Changes in GDB-4.6:
4865 * Better support for C++ function names
4867 GDB now accepts as input the "demangled form" of C++ overloaded function
4868 names and member function names, and can do command completion on such names
4869 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4870 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4871 Make use of command completion, it is your friend.
4873 GDB also now accepts a variety of C++ mangled symbol formats. They are
4874 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4875 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4876 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4877 for the list of formats.
4879 * G++ symbol mangling problem
4881 Recent versions of gcc have a bug in how they emit debugging information for
4882 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4883 directory) can be applied to gcc to fix the problem. Alternatively, if you
4884 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4885 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4886 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4889 * New 'maintenance' command
4891 All of the commands related to hacking GDB internals have been moved out of
4892 the main command set, and now live behind the 'maintenance' command. This
4893 can also be abbreviated as 'mt'. The following changes were made:
4895 dump-me -> maintenance dump-me
4896 info all-breakpoints -> maintenance info breakpoints
4897 printmsyms -> maintenance print msyms
4898 printobjfiles -> maintenance print objfiles
4899 printpsyms -> maintenance print psymbols
4900 printsyms -> maintenance print symbols
4902 The following commands are new:
4904 maintenance demangle Call internal GDB demangler routine to
4905 demangle a C++ link name and prints the result.
4906 maintenance print type Print a type chain for a given symbol
4908 * Change to .gdbinit file processing
4910 We now read the $HOME/.gdbinit file before processing the argv arguments
4911 (e.g. reading symbol files or core files). This allows global parameters to
4912 be set, which will apply during the symbol reading. The ./.gdbinit is still
4913 read after argv processing.
4915 * New hosts supported
4917 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4919 GNU/Linux support i386-unknown-linux or linux
4921 We are also including code to support the HP/PA running BSD and HPUX. This
4922 is almost guaranteed not to work, as we didn't have time to test or build it
4923 for this release. We are including it so that the more adventurous (or
4924 masochistic) of you can play with it. We also had major problems with the
4925 fact that the compiler that we got from HP doesn't support the -g option.
4928 * New targets supported
4930 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4932 * More smarts about finding #include files
4934 GDB now remembers the compilation directory for all include files, and for
4935 all files from which C is generated (like yacc and lex sources). This
4936 greatly improves GDB's ability to find yacc/lex sources, and include files,
4937 especially if you are debugging your program from a directory different from
4938 the one that contains your sources.
4940 We also fixed a bug which caused difficulty with listing and setting
4941 breakpoints in include files which contain C code. (In the past, you had to
4942 try twice in order to list an include file that you hadn't looked at before.)
4944 * Interesting infernals change
4946 GDB now deals with arbitrary numbers of sections, where the symbols for each
4947 section must be relocated relative to that section's landing place in the
4948 target's address space. This work was needed to support ELF with embedded
4949 stabs used by Solaris-2.0.
4951 * Bug fixes (of course!)
4953 There have been loads of fixes for the following things:
4954 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4955 i960, stabs, DOS(GO32), procfs, etc...
4957 See the ChangeLog for details.
4959 *** Changes in GDB-4.5:
4961 * New machines supported (host and target)
4963 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4965 SGI Irix-4.x mips-sgi-irix4 or iris4
4967 * New malloc package
4969 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4970 Mmalloc is capable of handling mutiple heaps of memory. It is also
4971 capable of saving a heap to a file, and then mapping it back in later.
4972 This can be used to greatly speedup the startup of GDB by using a
4973 pre-parsed symbol table which lives in a mmalloc managed heap. For
4974 more details, please read mmalloc/mmalloc.texi.
4978 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4979 'help info proc' for details.
4981 * MIPS ecoff symbol table format
4983 The code that reads MIPS symbol table format is now supported on all hosts.
4984 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4987 * File name changes for MS-DOS
4989 Many files in the config directories have been renamed to make it easier to
4990 support GDB on MS-DOSe systems (which have very restrictive file name
4991 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4992 environment) is close to working but has some remaining problems. Note
4993 that debugging of DOS programs is not supported, due to limitations
4994 in the ``operating system'', but it can be used to host cross-debugging.
4996 * Cross byte order fixes
4998 Many fixes have been made to support cross debugging of Sparc and MIPS
4999 targets from hosts whose byte order differs.
5001 * New -mapped and -readnow options
5003 If memory-mapped files are available on your system through the 'mmap'
5004 system call, you can use the -mapped option on the `file' or
5005 `symbol-file' commands to cause GDB to write the symbols from your
5006 program into a reusable file. If the program you are debugging is
5007 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5008 Future GDB debugging sessions will notice the presence of this file,
5009 and will quickly map in symbol information from it, rather than reading
5010 the symbol table from the executable program. Using the '-mapped'
5011 option in a GDB `file' or `symbol-file' command has the same effect as
5012 starting GDB with the '-mapped' command-line option.
5014 You can cause GDB to read the entire symbol table immediately by using
5015 the '-readnow' option with any of the commands that load symbol table
5016 information (or on the GDB command line). This makes the command
5017 slower, but makes future operations faster.
5019 The -mapped and -readnow options are typically combined in order to
5020 build a `fred.syms' file that contains complete symbol information.
5021 A simple GDB invocation to do nothing but build a `.syms' file for future
5024 gdb -batch -nx -mapped -readnow programname
5026 The `.syms' file is specific to the host machine on which GDB is run.
5027 It holds an exact image of GDB's internal symbol table. It cannot be
5028 shared across multiple host platforms.
5030 * longjmp() handling
5032 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5033 siglongjmp() without losing control. This feature has not yet been ported to
5034 all systems. It currently works on many 386 platforms, all MIPS-based
5035 platforms (SGI, DECstation, etc), and Sun3/4.
5039 Preliminary work has been put in to support the new Solaris OS from Sun. At
5040 this time, it can control and debug processes, but it is not capable of
5045 As always, many many bug fixes. The major areas were with g++, and mipsread.
5046 People using the MIPS-based platforms should experience fewer mysterious
5047 crashes and trashed symbol tables.
5049 *** Changes in GDB-4.4:
5051 * New machines supported (host and target)
5053 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5055 BSD Reno on Vax vax-dec-bsd
5056 Ultrix on Vax vax-dec-ultrix
5058 * New machines supported (target)
5060 AMD 29000 embedded, using EBMON a29k-none-none
5064 GDB continues to improve its handling of C++. `References' work better.
5065 The demangler has also been improved, and now deals with symbols mangled as
5066 per the Annotated C++ Reference Guide.
5068 GDB also now handles `stabs' symbol information embedded in MIPS
5069 `ecoff' symbol tables. Since the ecoff format was not easily
5070 extensible to handle new languages such as C++, this appeared to be a
5071 good way to put C++ debugging info into MIPS binaries. This option
5072 will be supported in the GNU C compiler, version 2, when it is
5075 * New features for SVR4
5077 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5078 shared libraries. Debugging dynamically linked programs should present
5079 only minor differences from debugging statically linked programs.
5081 The `info proc' command will print out information about any process
5082 on an SVR4 system (including the one you are debugging). At the moment,
5083 it prints the address mappings of the process.
5085 If you bring up GDB on another SVR4 system, please send mail to
5086 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5088 * Better dynamic linking support in SunOS
5090 Reading symbols from shared libraries which contain debugging symbols
5091 now works properly. However, there remain issues such as automatic
5092 skipping of `transfer vector' code during function calls, which
5093 make it harder to debug code in a shared library, than to debug the
5094 same code linked statically.
5098 GDB is now using the latest `getopt' routines from the FSF. This
5099 version accepts the -- prefix for options with long names. GDB will
5100 continue to accept the old forms (-option and +option) as well.
5101 Various single letter abbreviations for options have been explicity
5102 added to the option table so that they won't get overshadowed in the
5103 future by other options that begin with the same letter.
5107 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5108 Many assorted bugs have been handled. Many more remain to be handled.
5109 See the various ChangeLog files (primarily in gdb and bfd) for details.
5112 *** Changes in GDB-4.3:
5114 * New machines supported (host and target)
5116 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5117 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5118 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5120 * Almost SCO Unix support
5122 We had hoped to support:
5123 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5124 (except for core file support), but we discovered very late in the release
5125 that it has problems with process groups that render gdb unusable. Sorry
5126 about that. I encourage people to fix it and post the fixes.
5128 * Preliminary ELF and DWARF support
5130 GDB can read ELF object files on System V Release 4, and can handle
5131 debugging records for C, in DWARF format, in ELF files. This support
5132 is preliminary. If you bring up GDB on another SVR4 system, please
5133 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5138 GDB now uses the latest `readline' library. One user-visible change
5139 is that two tabs will list possible command completions, which previously
5140 required typing M-? (meta-question mark, or ESC ?).
5144 The `stepi' bug that many of you noticed has been squashed.
5145 Many bugs in C++ have been handled. Many more remain to be handled.
5146 See the various ChangeLog files (primarily in gdb and bfd) for details.
5148 * State of the MIPS world (in case you wondered):
5150 GDB can understand the symbol tables emitted by the compilers
5151 supplied by most vendors of MIPS-based machines, including DEC. These
5152 symbol tables are in a format that essentially nobody else uses.
5154 Some versions of gcc come with an assembler post-processor called
5155 mips-tfile. This program is required if you want to do source-level
5156 debugging of gcc-compiled programs. I believe FSF does not ship
5157 mips-tfile with gcc version 1, but it will eventually come with gcc
5160 Debugging of g++ output remains a problem. g++ version 1.xx does not
5161 really support it at all. (If you're lucky, you should be able to get
5162 line numbers and stack traces to work, but no parameters or local
5163 variables.) With some work it should be possible to improve the
5166 When gcc version 2 is released, you will have somewhat better luck.
5167 However, even then you will get confusing results for inheritance and
5170 We will eventually provide full debugging of g++ output on
5171 DECstations. This will probably involve some kind of stabs-in-ecoff
5172 encapulation, but the details have not been worked out yet.
5175 *** Changes in GDB-4.2:
5177 * Improved configuration
5179 Only one copy of `configure' exists now, and it is not self-modifying.
5180 Porting BFD is simpler.
5184 The `step' and `next' commands now only stop at the first instruction
5185 of a source line. This prevents the multiple stops that used to occur
5186 in switch statements, for-loops, etc. `Step' continues to stop if a
5187 function that has debugging information is called within the line.
5191 Lots of small bugs fixed. More remain.
5193 * New host supported (not target)
5195 Intel 386 PC clone running Mach i386-none-mach
5198 *** Changes in GDB-4.1:
5200 * Multiple source language support
5202 GDB now has internal scaffolding to handle several source languages.
5203 It determines the type of each source file from its filename extension,
5204 and will switch expression parsing and number formatting to match the
5205 language of the function in the currently selected stack frame.
5206 You can also specifically set the language to be used, with
5207 `set language c' or `set language modula-2'.
5211 GDB now has preliminary support for the GNU Modula-2 compiler,
5212 currently under development at the State University of New York at
5213 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5214 continue through the fall of 1991 and into 1992.
5216 Other Modula-2 compilers are currently not supported, and attempting to
5217 debug programs compiled with them will likely result in an error as the
5218 symbol table is read. Feel free to work on it, though!
5220 There are hooks in GDB for strict type checking and range checking,
5221 in the `Modula-2 philosophy', but they do not currently work.
5225 GDB can now write to executable and core files (e.g. patch
5226 a variable's value). You must turn this switch on, specify
5227 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5228 by assigning a new value to a variable. Modifications take
5231 * Automatic SunOS shared library reading
5233 When you run your program, GDB automatically determines where its
5234 shared libraries (if any) have been loaded, and reads their symbols.
5235 The `share' command is no longer needed. This also works when
5236 examining core files.
5240 You can specify the number of lines that the `list' command shows.
5243 * New machines supported (host and target)
5245 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5246 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5247 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5249 * New hosts supported (not targets)
5251 IBM RT/PC: romp-ibm-aix or rtpc
5253 * New targets supported (not hosts)
5255 AMD 29000 embedded with COFF a29k-none-coff
5256 AMD 29000 embedded with a.out a29k-none-aout
5257 Ultracomputer remote kernel debug a29k-nyu-kern
5259 * New remote interfaces
5265 *** Changes in GDB-4.0:
5269 Wide output is wrapped at good places to make the output more readable.
5271 Gdb now supports cross-debugging from a host machine of one type to a
5272 target machine of another type. Communication with the target system
5273 is over serial lines. The ``target'' command handles connecting to the
5274 remote system; the ``load'' command will download a program into the
5275 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5276 also supports debugging of realtime processes running under VxWorks,
5277 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5278 stub on the target system.
5280 New CPUs supported include the AMD 29000 and Intel 960.
5282 GDB now reads object files and symbol tables via a ``binary file''
5283 library, which allows a single copy of GDB to debug programs of multiple
5284 object file types such as a.out and coff.
5286 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5287 refcard.dvi and refcard.ps are available to format it).
5290 * Control-Variable user interface simplified
5292 All variables that control the operation of the debugger can be set
5293 by the ``set'' command, and displayed by the ``show'' command.
5295 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5296 ``Show prompt'' produces the response:
5297 Gdb's prompt is new-gdb=>.
5299 What follows are the NEW set commands. The command ``help set'' will
5300 print a complete list of old and new set commands. ``help set FOO''
5301 will give a longer description of the variable FOO. ``show'' will show
5302 all of the variable descriptions and their current settings.
5304 confirm on/off: Enables warning questions for operations that are
5305 hard to recover from, e.g. rerunning the program while
5306 it is already running. Default is ON.
5308 editing on/off: Enables EMACS style command line editing
5309 of input. Previous lines can be recalled with
5310 control-P, the current line can be edited with control-B,
5311 you can search for commands with control-R, etc.
5314 history filename NAME: NAME is where the gdb command history
5315 will be stored. The default is .gdb_history,
5316 or the value of the environment variable
5319 history size N: The size, in commands, of the command history. The
5320 default is 256, or the value of the environment variable
5323 history save on/off: If this value is set to ON, the history file will
5324 be saved after exiting gdb. If set to OFF, the
5325 file will not be saved. The default is OFF.
5327 history expansion on/off: If this value is set to ON, then csh-like
5328 history expansion will be performed on
5329 command line input. The default is OFF.
5331 radix N: Sets the default radix for input and output. It can be set
5332 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5333 in the current radix, so "set radix 10" is always a no-op.
5335 height N: This integer value is the number of lines on a page. Default
5336 is 24, the current `stty rows'' setting, or the ``li#''
5337 setting from the termcap entry matching the environment
5340 width N: This integer value is the number of characters on a line.
5341 Default is 80, the current `stty cols'' setting, or the ``co#''
5342 setting from the termcap entry matching the environment
5345 Note: ``set screensize'' is obsolete. Use ``set height'' and
5346 ``set width'' instead.
5348 print address on/off: Print memory addresses in various command displays,
5349 such as stack traces and structure values. Gdb looks
5350 more ``symbolic'' if you turn this off; it looks more
5351 ``machine level'' with it on. Default is ON.
5353 print array on/off: Prettyprint arrays. New convenient format! Default
5356 print demangle on/off: Print C++ symbols in "source" form if on,
5359 print asm-demangle on/off: Same, for assembler level printouts
5362 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5365 * Support for Epoch Environment.
5367 The epoch environment is a version of Emacs v18 with windowing. One
5368 new command, ``inspect'', is identical to ``print'', except that if you
5369 are running in the epoch environment, the value is printed in its own
5373 * Support for Shared Libraries
5375 GDB can now debug programs and core files that use SunOS shared libraries.
5376 Symbols from a shared library cannot be referenced
5377 before the shared library has been linked with the program (this
5378 happens after you type ``run'' and before the function main() is entered).
5379 At any time after this linking (including when examining core files
5380 from dynamically linked programs), gdb reads the symbols from each
5381 shared library when you type the ``sharedlibrary'' command.
5382 It can be abbreviated ``share''.
5384 sharedlibrary REGEXP: Load shared object library symbols for files
5385 matching a unix regular expression. No argument
5386 indicates to load symbols for all shared libraries.
5388 info sharedlibrary: Status of loaded shared libraries.
5393 A watchpoint stops execution of a program whenever the value of an
5394 expression changes. Checking for this slows down execution
5395 tremendously whenever you are in the scope of the expression, but is
5396 quite useful for catching tough ``bit-spreader'' or pointer misuse
5397 problems. Some machines such as the 386 have hardware for doing this
5398 more quickly, and future versions of gdb will use this hardware.
5400 watch EXP: Set a watchpoint (breakpoint) for an expression.
5402 info watchpoints: Information about your watchpoints.
5404 delete N: Deletes watchpoint number N (same as breakpoints).
5405 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5406 enable N: Re-enables watchpoint number N (same as breakpoints).
5409 * C++ multiple inheritance
5411 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5414 * C++ exception handling
5416 Gdb now supports limited C++ exception handling. Besides the existing
5417 ability to breakpoint on an exception handler, gdb can breakpoint on
5418 the raising of an exception (before the stack is peeled back to the
5421 catch FOO: If there is a FOO exception handler in the dynamic scope,
5422 set a breakpoint to catch exceptions which may be raised there.
5423 Multiple exceptions (``catch foo bar baz'') may be caught.
5425 info catch: Lists all exceptions which may be caught in the
5426 current stack frame.
5429 * Minor command changes
5431 The command ``call func (arg, arg, ...)'' now acts like the print
5432 command, except it does not print or save a value if the function's result
5433 is void. This is similar to dbx usage.
5435 The ``up'' and ``down'' commands now always print the frame they end up
5436 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5437 frames without printing.
5439 * New directory command
5441 'dir' now adds directories to the FRONT of the source search path.
5442 The path starts off empty. Source files that contain debug information
5443 about the directory in which they were compiled can be found even
5444 with an empty path; Sun CC and GCC include this information. If GDB can't
5445 find your source file in the current directory, type "dir .".
5447 * Configuring GDB for compilation
5449 For normal use, type ``./configure host''. See README or gdb.texinfo
5452 GDB now handles cross debugging. If you are remotely debugging between
5453 two different machines, type ``./configure host -target=targ''.
5454 Host is the machine where GDB will run; targ is the machine
5455 where the program that you are debugging will run.