1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.6
6 * The "maintenance print objfiles" command now takes an optional regexp.
8 * The "catch syscall" command now works on arm*-linux* targets.
12 ** Frame filters and frame decorators have been added.
16 Nios II ELF nios2*-*-elf
17 Nios II GNU/Linux nios2*-*-linux
18 Texas Instruments MSP430 msp430*-*-elf
22 Like "catch throw", but catches a re-thrown exception.
24 Renamed from old "maint check-symtabs".
26 Perform consistency checks on symtabs.
28 Expand symtabs matching an optional regexp.
31 Display the details of GDB configure-time options.
33 maint set|show per-command
34 maint set|show per-command space
35 maint set|show per-command time
36 maint set|show per-command symtab
37 Enable display of per-command gdb resource usage.
41 set print raw frame-arguments
42 show print raw frame-arguments
43 Set/show whether to print frame arguments in raw mode,
44 disregarding any defined pretty-printers.
46 set remote trace-status-packet
47 show remote trace-status-packet
48 Set/show the use of remote protocol qTStatus packet.
52 Control display of debugging messages related to Nios II targets.
56 Control whether target-assisted range stepping is enabled.
58 * You can now use a literal value 'unlimited' for options that
59 interpret 0 or -1 as meaning "unlimited". E.g., "set
60 trace-buffer-size unlimited" is now an alias for "set
61 trace-buffer-size -1" and "set height unlimited" is now an alias for
64 * New command-line options
66 Display the details of GDB configure-time options.
68 * The command 'tsave' can now support new option '-ctf' to save trace
69 buffer in Common Trace Format.
71 * Newly installed $prefix/bin/gcore acts as a shell interface for the
74 * GDB now implements the the C++ 'typeid' operator.
76 * The new convenience variable $_exception holds the exception being
77 thrown or caught at an exception-related catchpoint.
79 * The exception-related catchpoints, like "catch throw", now accept a
80 regular expression which can be used to filter exceptions by type.
84 ** The -trace-save MI command can optionally save trace buffer in Common
87 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
89 ** The command -data-list-register-values now accepts an optional
90 "--skip-unavailable" option. When used, only the available registers
93 ** The new command -trace-frame-collected dumps collected variables,
94 computed expressions, tvars, memory and registers in a traceframe.
96 ** The commands -stack-list-locals, -stack-list-arguments and
97 -stack-list-variables now accept an option "--skip-unavailable".
98 When used, only the available locals or arguments are displayed.
100 * New system-wide configuration scripts
101 A GDB installation now provides scripts suitable for use as system-wide
102 configuration scripts for the following systems:
106 * GDB now supports target-assigned range stepping with remote targets.
107 This improves the performance of stepping source lines by reducing
108 the number of control packets from/to GDB. See "New remote packets"
111 * GDB now understands the element 'tvar' in the XML traceframe info.
112 It has the id of the collected trace state variables.
118 The vCont packet supports a new 'r' action, that tells the remote
119 stub to step through an address range itself, without GDB
120 involvemement at each single-step.
122 qXfer:libraries-svr4:read's annex
123 The previously unused annex of the qXfer:libraries-svr4:read packet
124 is now used to support passing an argument list. The remote stub
125 reports support for this argument list to GDB's qSupported query.
126 The defined arguments are "start" and "prev", used to reduce work
127 necessary for library list updating, resulting in significant
130 * New features in the GDB remote stub, GDBserver
132 ** GDBserver now supports target-assisted range stepping. Currently
133 enabled on x86/x86_64 GNU/Linux targets.
135 ** GDBserver now adds element 'tvar' in the XML in the reply to
136 'qXfer:traceframe-info:read'. It has the id of the collected
137 trace state variables.
139 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
142 * New 'z' formatter for printing and examining memory, this displays the
143 value as hexadecimal zero padded on the left to the size of the type.
145 *** Changes in GDB 7.6
147 * Target record has been renamed to record-full.
148 Record/replay is now enabled with the "record full" command.
149 This also affects settings that are associated with full record/replay
150 that have been moved from "set/show record" to "set/show record full":
152 set|show record full insn-number-max
153 set|show record full stop-at-limit
154 set|show record full memory-query
156 * A new record target "record-btrace" has been added. The new target
157 uses hardware support to record the control-flow of a process. It
158 does not support replaying the execution, but it implements the
159 below new commands for investigating the recorded execution log.
160 This new recording method can be enabled using:
164 The "record-btrace" target is only available on Intel Atom processors
165 and requires a Linux kernel 2.6.32 or later.
167 * Two new commands have been added for record/replay to give information
168 about the recorded execution without having to replay the execution.
169 The commands are only supported by "record btrace".
171 record instruction-history prints the execution history at
172 instruction granularity
174 record function-call-history prints the execution history at
177 * New native configurations
179 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
180 FreeBSD/powerpc powerpc*-*-freebsd
181 x86_64/Cygwin x86_64-*-cygwin*
182 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
186 ARM AArch64 aarch64*-*-elf
187 ARM AArch64 GNU/Linux aarch64*-*-linux
188 Lynx 178 PowerPC powerpc-*-lynx*178
189 x86_64/Cygwin x86_64-*-cygwin*
190 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
192 * If the configured location of system.gdbinit file (as given by the
193 --with-system-gdbinit option at configure time) is in the
194 data-directory (as specified by --with-gdb-datadir at configure
195 time) or in one of its subdirectories, then GDB will look for the
196 system-wide init file in the directory specified by the
197 --data-directory command-line option.
199 * New command line options:
201 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
202 other initialization files, unlike -nx which disables all of them.
204 * Removed command line options
206 -epoch This was used by the gdb mode in Epoch, an ancient fork of
209 * The 'ptype' and 'whatis' commands now accept an argument to control
212 * 'info proc' now works on some core files.
216 ** Vectors can be created with gdb.Type.vector.
218 ** Python's atexit.register now works in GDB.
220 ** Types can be pretty-printed via a Python API.
222 ** Python 3 is now supported (in addition to Python 2.4 or later)
224 ** New class gdb.Architecture exposes GDB's internal representation
225 of architecture in the Python API.
227 ** New method Frame.architecture returns the gdb.Architecture object
228 corresponding to the frame's architecture.
230 * New Python-based convenience functions:
232 ** $_memeq(buf1, buf2, length)
233 ** $_streq(str1, str2)
235 ** $_regex(str, regex)
237 * The 'cd' command now defaults to using '~' (the home directory) if not
240 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
241 default for GCC since November 2000.
243 * The command 'forward-search' can now be abbreviated as 'fo'.
245 * The command 'info tracepoints' can now display 'installed on target'
246 or 'not installed on target' for each non-pending location of tracepoint.
248 * New configure options
250 --enable-libmcheck/--disable-libmcheck
251 By default, development versions are built with -lmcheck on hosts
252 that support it, in order to help track memory corruption issues.
253 Release versions, on the other hand, are built without -lmcheck
254 by default. The --enable-libmcheck/--disable-libmcheck configure
255 options allow the user to override that default.
256 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
257 This configure option allows the user to build GDB with
258 libbabeltrace using which GDB can read Common Trace Format data.
260 * New commands (for set/show, see "New options" below)
263 Catch signals. This is similar to "handle", but allows commands and
264 conditions to be attached.
267 List the BFDs known to GDB.
269 python-interactive [command]
271 Start a Python interactive prompt, or evaluate the optional command
272 and print the result of expressions.
275 "py" is a new alias for "python".
277 enable type-printer [name]...
278 disable type-printer [name]...
279 Enable or disable type printers.
283 ** For the Renesas Super-H architecture, the "regs" command has been removed
284 (has been deprecated in GDB 7.5), and "info all-registers" should be used
289 set print type methods (on|off)
290 show print type methods
291 Control whether method declarations are displayed by "ptype".
292 The default is to show them.
294 set print type typedefs (on|off)
295 show print type typedefs
296 Control whether typedef definitions are displayed by "ptype".
297 The default is to show them.
299 set filename-display basename|relative|absolute
300 show filename-display
301 Control the way in which filenames is displayed.
302 The default is "relative", which preserves previous behavior.
304 set trace-buffer-size
305 show trace-buffer-size
306 Request target to change the size of trace buffer.
308 set remote trace-buffer-size-packet auto|on|off
309 show remote trace-buffer-size-packet
310 Control the use of the remote protocol `QTBuffer:size' packet.
314 Control display of debugging messages related to ARM AArch64.
317 set debug coff-pe-read
318 show debug coff-pe-read
319 Control display of debugging messages related to reading of COFF/PE
324 Control display of debugging messages related to Mach-O symbols
327 set debug notification
328 show debug notification
329 Control display of debugging info for async remote notification.
333 ** Command parameter changes are now notified using new async record
334 "=cmd-param-changed".
335 ** Trace frame changes caused by command "tfind" are now notified using
336 new async record "=traceframe-changed".
337 ** The creation, deletion and modification of trace state variables
338 are now notified using new async records "=tsv-created",
339 "=tsv-deleted" and "=tsv-modified".
340 ** The start and stop of process record are now notified using new
341 async record "=record-started" and "=record-stopped".
342 ** Memory changes are now notified using new async record
344 ** The data-disassemble command response will include a "fullname" field
345 containing the absolute file name when source has been requested.
346 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
347 command, to allow pattern filling of memory areas.
348 ** New commands "-catch-load"/"-catch-unload" added for intercepting
349 library load/unload events.
350 ** The response to breakpoint commands and breakpoint async records
351 includes an "installed" field containing a boolean state about each
352 non-pending tracepoint location is whether installed on target or not.
353 ** Output of the "-trace-status" command includes a "trace-file" field
354 containing the name of the trace file being examined. This field is
355 optional, and only present when examining a trace file.
356 ** The "fullname" field is now always present along with the "file" field,
357 even if the file cannot be found by GDB.
359 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
360 You must have the LZMA library available when configuring GDB for this
361 feature to be enabled. For more information, see:
362 http://fedoraproject.org/wiki/Features/MiniDebugInfo
367 Set the size of trace buffer. The remote stub reports support for this
368 packet to gdb's qSupported query.
371 Enable Branch Trace Store (BTS)-based branch tracing for the current
372 thread. The remote stub reports support for this packet to gdb's
376 Disable branch tracing for the current thread. The remote stub reports
377 support for this packet to gdb's qSupported query.
380 Read the traced branches for the current thread. The remote stub
381 reports support for this packet to gdb's qSupported query.
383 *** Changes in GDB 7.5
385 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
386 for more x32 ABI info.
388 * GDB now supports access to MIPS DSP registers on Linux targets.
390 * GDB now supports debugging microMIPS binaries.
392 * The "info os" command on GNU/Linux can now display information on
393 several new classes of objects managed by the operating system:
394 "info os procgroups" lists process groups
395 "info os files" lists file descriptors
396 "info os sockets" lists internet-domain sockets
397 "info os shm" lists shared-memory regions
398 "info os semaphores" lists semaphores
399 "info os msg" lists message queues
400 "info os modules" lists loaded kernel modules
402 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
403 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
404 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
405 options and inspect the probe arguments using the new $_probe_arg family
406 of convenience variables. You can obtain more information about SystemTap
407 in <http://sourceware.org/systemtap/>.
409 * GDB now supports reversible debugging on ARM, it allows you to
410 debug basic ARM and THUMB instructions, and provides
411 record/replay support.
413 * The option "symbol-reloading" has been deleted as it is no longer used.
417 ** GDB commands implemented in Python can now be put in command class
420 ** The "maint set python print-stack on|off" is now deleted.
422 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
423 apply "flag enum"-style pretty-printing to any enum.
425 ** gdb.lookup_symbol can now work when there is no current frame.
427 ** gdb.Symbol now has a 'line' attribute, holding the line number in
428 the source at which the symbol was defined.
430 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
431 method 'value'. The former indicates whether the symbol needs a
432 frame in order to compute its value, and the latter computes the
435 ** A new method 'referenced_value' on gdb.Value objects which can
436 dereference pointer as well as C++ reference values.
438 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
439 which return the global and static blocks (as gdb.Block objects),
440 of the underlying symbol table, respectively.
442 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
443 object associated with a PC value.
445 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
446 of the address range occupied by code for the current source line.
448 * Go language support.
449 GDB now supports debugging programs written in the Go programming
452 * GDBserver now supports stdio connections.
453 E.g. (gdb) target remote | ssh myhost gdbserver - hello
455 * The binary "gdbtui" can no longer be built or installed.
456 Use "gdb -tui" instead.
458 * GDB will now print "flag" enums specially. A flag enum is one where
459 all the enumerator values have no bits in common when pairwise
460 "and"ed. When printing a value whose type is a flag enum, GDB will
461 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
462 (gdb) print (enum E) 3
465 * The filename part of a linespec will now match trailing components
466 of a source file name. For example, "break gcc/expr.c:1000" will
467 now set a breakpoint in build/gcc/expr.c, but not
470 * The "info proc" and "generate-core-file" commands will now also
471 work on remote targets connected to GDBserver on Linux.
473 * The command "info catch" has been removed. It has been disabled
476 * The "catch exception" and "catch assert" commands now accept
477 a condition at the end of the command, much like the "break"
478 command does. For instance:
480 (gdb) catch exception Constraint_Error if Barrier = True
482 Previously, it was possible to add a condition to such catchpoints,
483 but it had to be done as a second step, after the catchpoint had been
484 created, using the "condition" command.
486 * The "info static-tracepoint-marker" command will now also work on
487 native Linux targets with in-process agent.
489 * GDB can now set breakpoints on inlined functions.
491 * The .gdb_index section has been updated to include symbols for
492 inlined functions. GDB will ignore older .gdb_index sections by
493 default, which could cause symbol files to be loaded more slowly
494 until their .gdb_index sections can be recreated. The new command
495 "set use-deprecated-index-sections on" will cause GDB to use any older
496 .gdb_index sections it finds. This will restore performance, but the
497 ability to set breakpoints on inlined functions will be lost in symbol
498 files with older .gdb_index sections.
500 The .gdb_index section has also been updated to record more information
501 about each symbol. This speeds up the "info variables", "info functions"
502 and "info types" commands when used with programs having the .gdb_index
503 section, as well as speeding up debugging with shared libraries using
504 the .gdb_index section.
506 * Ada support for GDB/MI Variable Objects has been added.
508 * GDB can now support 'breakpoint always-inserted mode' in 'record'
513 ** New command -info-os is the MI equivalent of "info os".
515 ** Output logs ("set logging" and related) now include MI output.
519 ** "set use-deprecated-index-sections on|off"
520 "show use-deprecated-index-sections on|off"
521 Controls the use of deprecated .gdb_index sections.
523 ** "catch load" and "catch unload" can be used to stop when a shared
524 library is loaded or unloaded, respectively.
526 ** "enable count" can be used to auto-disable a breakpoint after
529 ** "info vtbl" can be used to show the virtual method tables for
530 C++ and Java objects.
532 ** "explore" and its sub commands "explore value" and "explore type"
533 can be used to reccursively explore values and types of
534 expressions. These commands are available only if GDB is
535 configured with '--with-python'.
537 ** "info auto-load" shows status of all kinds of auto-loaded files,
538 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
539 sequences of commands files, "info auto-load python-scripts"
540 shows status of auto-loading Python script files,
541 "info auto-load local-gdbinit" shows status of loading init file
542 (.gdbinit) from current directory and "info auto-load libthread-db" shows
543 status of inferior specific thread debugging shared library loading.
545 ** "info auto-load-scripts", "set auto-load-scripts on|off"
546 and "show auto-load-scripts" commands have been deprecated, use their
547 "info auto-load python-scripts", "set auto-load python-scripts on|off"
548 and "show auto-load python-scripts" counterparts instead.
550 ** "dprintf location,format,args..." creates a dynamic printf, which
551 is basically a breakpoint that does a printf and immediately
552 resumes your program's execution, so it is like a printf that you
553 can insert dynamically at runtime instead of at compiletime.
555 ** "set print symbol"
557 Controls whether GDB attempts to display the symbol, if any,
558 corresponding to addresses it prints. This defaults to "on", but
559 you can set it to "off" to restore GDB's previous behavior.
561 * Deprecated commands
563 ** For the Renesas Super-H architecture, the "regs" command has been
564 deprecated, and "info all-registers" should be used instead.
568 Renesas RL78 rl78-*-elf
569 HP OpenVMS ia64 ia64-hp-openvms*
571 * GDBserver supports evaluation of breakpoint conditions. When
572 support is advertised by GDBserver, GDB may be told to send the
573 breakpoint conditions in bytecode form to GDBserver. GDBserver
574 will only report the breakpoint trigger to GDB when its condition
580 show mips compression
581 Select the compressed ISA encoding used in functions that have no symbol
582 information available. The encoding can be set to either of:
585 and is updated automatically from ELF file flags if available.
587 set breakpoint condition-evaluation
588 show breakpoint condition-evaluation
589 Control whether breakpoint conditions are evaluated by GDB ("host") or by
590 GDBserver ("target"). Default option "auto" chooses the most efficient
592 This option can improve debugger efficiency depending on the speed of the
596 Disable auto-loading globally.
599 Show auto-loading setting of all kinds of auto-loaded files.
601 set auto-load gdb-scripts on|off
602 show auto-load gdb-scripts
603 Control auto-loading of GDB canned sequences of commands files.
605 set auto-load python-scripts on|off
606 show auto-load python-scripts
607 Control auto-loading of Python script files.
609 set auto-load local-gdbinit on|off
610 show auto-load local-gdbinit
611 Control loading of init file (.gdbinit) from current directory.
613 set auto-load libthread-db on|off
614 show auto-load libthread-db
615 Control auto-loading of inferior specific thread debugging shared library.
617 set auto-load scripts-directory <dir1>[:<dir2>...]
618 show auto-load scripts-directory
619 Set a list of directories from which to load auto-loaded scripts.
620 Automatically loaded Python scripts and GDB scripts are located in one
621 of the directories listed by this option.
622 The delimiter (':' above) may differ according to the host platform.
624 set auto-load safe-path <dir1>[:<dir2>...]
625 show auto-load safe-path
626 Set a list of directories from which it is safe to auto-load files.
627 The delimiter (':' above) may differ according to the host platform.
629 set debug auto-load on|off
631 Control display of debugging info for auto-loading the files above.
633 set dprintf-style gdb|call|agent
635 Control the way in which a dynamic printf is performed; "gdb"
636 requests a GDB printf command, while "call" causes dprintf to call a
637 function in the inferior. "agent" requests that the target agent
638 (such as GDBserver) do the printing.
640 set dprintf-function <expr>
641 show dprintf-function
642 set dprintf-channel <expr>
644 Set the function and optional first argument to the call when using
645 the "call" style of dynamic printf.
647 set disconnected-dprintf on|off
648 show disconnected-dprintf
649 Control whether agent-style dynamic printfs continue to be in effect
650 after GDB disconnects.
652 * New configure options
655 Configure default value for the 'set auto-load scripts-directory'
656 setting above. It defaults to '$debugdir:$datadir/auto-load',
657 $debugdir representing global debugging info directories (available
658 via 'show debug-file-directory') and $datadir representing GDB's data
659 directory (available via 'show data-directory').
661 --with-auto-load-safe-path
662 Configure default value for the 'set auto-load safe-path' setting
663 above. It defaults to the --with-auto-load-dir setting.
665 --without-auto-load-safe-path
666 Set 'set auto-load safe-path' to '/', effectively disabling this
671 z0/z1 conditional breakpoints extension
673 The z0/z1 breakpoint insertion packets have been extended to carry
674 a list of conditional expressions over to the remote stub depending on the
675 condition evaluation mode. The use of this extension can be controlled
676 via the "set remote conditional-breakpoints-packet" command.
680 Specify the signals which the remote stub may pass to the debugged
681 program without GDB involvement.
683 * New command line options
685 --init-command=FILE, -ix Like --command, -x but execute it
686 before loading inferior.
687 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
688 execute it before loading inferior.
690 *** Changes in GDB 7.4
692 * GDB now handles ambiguous linespecs more consistently; the existing
693 FILE:LINE support has been expanded to other types of linespecs. A
694 breakpoint will now be set on all matching locations in all
695 inferiors, and locations will be added or removed according to
698 * GDB now allows you to skip uninteresting functions and files when
699 stepping with the "skip function" and "skip file" commands.
701 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
702 and "show remote hardware-watchpoint-length-limit". These allows to
703 set or show the maximum length limit (in bytes) of a remote
704 target hardware watchpoint.
706 This allows e.g. to use "unlimited" hardware watchpoints with the
707 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
708 watchpoints are slower than real hardware watchpoints but are
709 significantly faster than gdb software watchpoints.
713 ** The register_pretty_printer function in module gdb.printing now takes
714 an optional `replace' argument. If True, the new printer replaces any
717 ** The "maint set python print-stack on|off" command has been
718 deprecated and will be deleted in GDB 7.5.
719 A new command: "set python print-stack none|full|message" has
720 replaced it. Additionally, the default for "print-stack" is
721 now "message", which just prints the error message without
724 ** A prompt substitution hook (prompt_hook) is now available to the
727 ** A new Python module, gdb.prompt has been added to the GDB Python
728 modules library. This module provides functionality for
729 escape sequences in prompts (used by set/show
730 extended-prompt). These escape sequences are replaced by their
733 ** Python commands and convenience-functions located in
734 'data-directory'/python/gdb/command and
735 'data-directory'/python/gdb/function are now automatically loaded
738 ** Blocks now provide four new attributes. global_block and
739 static_block will return the global and static blocks
740 respectively. is_static and is_global are boolean attributes
741 that indicate if the block is one of those two types.
743 ** Symbols now provide the "type" attribute, the type of the symbol.
745 ** The "gdb.breakpoint" function has been deprecated in favor of
748 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
749 of a function. This class is based on the "finish" command
750 available in the CLI.
752 ** Type objects for struct and union types now allow access to
753 the fields using standard Python dictionary (mapping) methods.
754 For example, "some_type['myfield']" now works, as does
757 ** A new event "gdb.new_objfile" has been added, triggered by loading a
760 ** A new function, "deep_items" has been added to the gdb.types
761 module in the GDB Python modules library. This function returns
762 an iterator over the fields of a struct or union type. Unlike
763 the standard Python "iteritems" method, it will recursively traverse
764 any anonymous fields.
768 ** "*stopped" events can report several new "reason"s, such as
771 ** Breakpoint changes are now notified using new async records, like
772 "=breakpoint-modified".
774 ** New command -ada-task-info.
776 * libthread-db-search-path now supports two special values: $sdir and $pdir.
777 $sdir specifies the default system locations of shared libraries.
778 $pdir specifies the directory where the libpthread used by the application
781 GDB no longer looks in $sdir and $pdir after it has searched the directories
782 mentioned in libthread-db-search-path. If you want to search those
783 directories, they must be specified in libthread-db-search-path.
784 The default value of libthread-db-search-path on GNU/Linux and Solaris
785 systems is now "$sdir:$pdir".
787 $pdir is not supported by gdbserver, it is currently ignored.
788 $sdir is supported by gdbserver.
790 * New configure option --with-iconv-bin.
791 When using the internationalization support like the one in the GNU C
792 library, GDB will invoke the "iconv" program to get a list of supported
793 character sets. If this program lives in a non-standard location, one can
794 use this option to specify where to find it.
796 * When natively debugging programs on PowerPC BookE processors running
797 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
798 watchpoints, which specify a mask in addition to an address to watch.
799 The mask specifies that some bits of an address (the bits which are
800 reset in the mask) should be ignored when matching the address accessed
801 by the inferior against the watchpoint address. See the "PowerPC Embedded"
802 section in the user manual for more details.
804 * The new option --once causes GDBserver to stop listening for connections once
805 the first connection is made. The listening port used by GDBserver will
806 become available after that.
808 * New commands "info macros" and "alias" have been added.
810 * New function parameters suffix @entry specifies value of function parameter
811 at the time the function got called. Entry values are available only since
817 "!" is now an alias of the "shell" command.
818 Note that no space is needed between "!" and SHELL COMMAND.
822 watch EXPRESSION mask MASK_VALUE
823 The watch command now supports the mask argument which allows creation
824 of masked watchpoints, if the current architecture supports this feature.
826 info auto-load-scripts [REGEXP]
827 This command was formerly named "maintenance print section-scripts".
828 It is now generally useful and is no longer a maintenance-only command.
830 info macro [-all] [--] MACRO
831 The info macro command has new options `-all' and `--'. The first for
832 printing all definitions of a macro. The second for explicitly specifying
833 the end of arguments and the beginning of the macro name in case the macro
834 name starts with a hyphen.
836 collect[/s] EXPRESSIONS
837 The tracepoint collect command now takes an optional modifier "/s"
838 that directs it to dereference pointer-to-character types and
839 collect the bytes of memory up to a zero byte. The behavior is
840 similar to what you see when you use the regular print command on a
841 string. An optional integer following the "/s" sets a bound on the
842 number of bytes that will be collected.
845 The trace start command now interprets any supplied arguments as a
846 note to be recorded with the trace run, with an effect similar to
847 setting the variable trace-notes.
850 The trace stop command now interprets any arguments as a note to be
851 mentioned along with the tstatus report that the trace was stopped
852 with a command. The effect is similar to setting the variable
855 * Tracepoints can now be enabled and disabled at any time after a trace
856 experiment has been started using the standard "enable" and "disable"
857 commands. It is now possible to start a trace experiment with no enabled
858 tracepoints; GDB will display a warning, but will allow the experiment to
859 begin, assuming that tracepoints will be enabled as needed while the trace
862 * Fast tracepoints on 32-bit x86-architectures can now be placed at
863 locations with 4-byte instructions, when they were previously
864 limited to locations with instructions of 5 bytes or longer.
868 set debug dwarf2-read
869 show debug dwarf2-read
870 Turns on or off display of debugging messages related to reading
871 DWARF debug info. The default is off.
873 set debug symtab-create
874 show debug symtab-create
875 Turns on or off display of debugging messages related to symbol table
876 creation. The default is off.
880 Set the GDB prompt, and allow escape sequences to be inserted to
881 display miscellaneous information (see 'help set extended-prompt'
882 for the list of sequences). This prompt (and any information
883 accessed through the escape sequences) is updated every time the
886 set print entry-values (both|compact|default|if-needed|no|only|preferred)
887 show print entry-values
888 Set printing of frame argument values at function entry. In some cases
889 GDB can determine the value of function argument which was passed by the
890 function caller, even if the value was modified inside the called function.
892 set debug entry-values
893 show debug entry-values
894 Control display of debugging info for determining frame argument values at
895 function entry and virtual tail call frames.
897 set basenames-may-differ
898 show basenames-may-differ
899 Set whether a source file may have multiple base names.
900 (A "base name" is the name of a file with the directory part removed.
901 Example: The base name of "/home/user/hello.c" is "hello.c".)
902 If set, GDB will canonicalize file names (e.g., expand symlinks)
903 before comparing them. Canonicalization is an expensive operation,
904 but it allows the same file be known by more than one base name.
905 If not set (the default), all source files are assumed to have just
906 one base name, and gdb will do file name comparisons more efficiently.
912 Set a user name and notes for the current and any future trace runs.
913 This is useful for long-running and/or disconnected traces, to
914 inform others (or yourself) as to who is running the trace, supply
915 contact information, or otherwise explain what is going on.
918 show trace-stop-notes
919 Set a note attached to the trace run, that is displayed when the
920 trace has been stopped by a tstop command. This is useful for
921 instance as an explanation, if you are stopping a trace run that was
922 started by someone else.
928 Dynamically enable a tracepoint in a started trace experiment.
932 Dynamically disable a tracepoint in a started trace experiment.
936 Set the user and notes of the trace run.
940 Query the current status of a tracepoint.
944 Query the minimum length of instruction at which a fast tracepoint may
947 * Dcache size (number of lines) and line-size are now runtime-configurable
948 via "set dcache line" and "set dcache line-size" commands.
952 Texas Instruments TMS320C6x tic6x-*-*
956 Renesas RL78 rl78-*-elf
958 *** Changes in GDB 7.3.1
960 * The build failure for NetBSD and OpenBSD targets have now been fixed.
962 *** Changes in GDB 7.3
964 * GDB has a new command: "thread find [REGEXP]".
965 It finds the thread id whose name, target id, or thread extra info
966 matches the given regular expression.
968 * The "catch syscall" command now works on mips*-linux* targets.
970 * The -data-disassemble MI command now supports modes 2 and 3 for
971 dumping the instruction opcodes.
973 * New command line options
975 -data-directory DIR Specify DIR as the "data-directory".
976 This is mostly for testing purposes.
978 * The "maint set python auto-load on|off" command has been renamed to
979 "set auto-load-scripts on|off".
981 * GDB has a new command: "set directories".
982 It is like the "dir" command except that it replaces the
983 source path list instead of augmenting it.
985 * GDB now understands thread names.
987 On GNU/Linux, "info threads" will display the thread name as set by
988 prctl or pthread_setname_np.
990 There is also a new command, "thread name", which can be used to
991 assign a name internally for GDB to display.
994 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
995 has been integrated into GDB.
999 ** The function gdb.Write now accepts an optional keyword 'stream'.
1000 This keyword, when provided, will direct the output to either
1001 stdout, stderr, or GDB's logging output.
1003 ** Parameters can now be be sub-classed in Python, and in particular
1004 you may implement the get_set_doc and get_show_doc functions.
1005 This improves how Parameter set/show documentation is processed
1006 and allows for more dynamic content.
1008 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1009 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1010 have an is_valid method.
1012 ** Breakpoints can now be sub-classed in Python, and in particular
1013 you may implement a 'stop' function that is executed each time
1014 the inferior reaches that breakpoint.
1016 ** New function gdb.lookup_global_symbol looks up a global symbol.
1018 ** GDB values in Python are now callable if the value represents a
1019 function. For example, if 'some_value' represents a function that
1020 takes two integer parameters and returns a value, you can call
1021 that function like so:
1023 result = some_value (10,20)
1025 ** Module gdb.types has been added.
1026 It contains a collection of utilities for working with gdb.Types objects:
1027 get_basic_type, has_field, make_enum_dict.
1029 ** Module gdb.printing has been added.
1030 It contains utilities for writing and registering pretty-printers.
1031 New classes: PrettyPrinter, SubPrettyPrinter,
1032 RegexpCollectionPrettyPrinter.
1033 New function: register_pretty_printer.
1035 ** New commands "info pretty-printers", "enable pretty-printer" and
1036 "disable pretty-printer" have been added.
1038 ** gdb.parameter("directories") is now available.
1040 ** New function gdb.newest_frame returns the newest frame in the
1043 ** The gdb.InferiorThread class has a new "name" attribute. This
1044 holds the thread's name.
1046 ** Python Support for Inferior events.
1047 Python scripts can add observers to be notified of events
1048 occurring in the process being debugged.
1049 The following events are currently supported:
1050 - gdb.events.cont Continue event.
1051 - gdb.events.exited Inferior exited event.
1052 - gdb.events.stop Signal received, and Breakpoint hit events.
1056 ** GDB now puts template parameters in scope when debugging in an
1057 instantiation. For example, if you have:
1059 template<int X> int func (void) { return X; }
1061 then if you step into func<5>, "print X" will show "5". This
1062 feature requires proper debuginfo support from the compiler; it
1063 was added to GCC 4.5.
1065 ** The motion commands "next", "finish", "until", and "advance" now
1066 work better when exceptions are thrown. In particular, GDB will
1067 no longer lose control of the inferior; instead, the GDB will
1068 stop the inferior at the point at which the exception is caught.
1069 This functionality requires a change in the exception handling
1070 code that was introduced in GCC 4.5.
1072 * GDB now follows GCC's rules on accessing volatile objects when
1073 reading or writing target state during expression evaluation.
1074 One notable difference to prior behavior is that "print x = 0"
1075 no longer generates a read of x; the value of the assignment is
1076 now always taken directly from the value being assigned.
1078 * GDB now has some support for using labels in the program's source in
1079 linespecs. For instance, you can use "advance label" to continue
1080 execution to a label.
1082 * GDB now has support for reading and writing a new .gdb_index
1083 section. This section holds a fast index of DWARF debugging
1084 information and can be used to greatly speed up GDB startup and
1085 operation. See the documentation for `save gdb-index' for details.
1087 * The "watch" command now accepts an optional "-location" argument.
1088 When used, this causes GDB to watch the memory referred to by the
1089 expression. Such a watchpoint is never deleted due to it going out
1092 * GDB now supports thread debugging of core dumps on GNU/Linux.
1094 GDB now activates thread debugging using the libthread_db library
1095 when debugging GNU/Linux core dumps, similarly to when debugging
1096 live processes. As a result, when debugging a core dump file, GDB
1097 is now able to display pthread_t ids of threads. For example, "info
1098 threads" shows the same output as when debugging the process when it
1099 was live. In earlier releases, you'd see something like this:
1102 * 1 LWP 6780 main () at main.c:10
1104 While now you see this:
1107 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1109 It is also now possible to inspect TLS variables when debugging core
1112 When debugging a core dump generated on a machine other than the one
1113 used to run GDB, you may need to point GDB at the correct
1114 libthread_db library with the "set libthread-db-search-path"
1115 command. See the user manual for more details on this command.
1117 * When natively debugging programs on PowerPC BookE processors running
1118 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1119 which stop execution of the inferior whenever it executes an instruction
1120 at any address within the specified range. See the "PowerPC Embedded"
1121 section in the user manual for more details.
1123 * New features in the GDB remote stub, GDBserver
1125 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1126 and i686 LynxOS (version 5.x).
1128 ** GDBserver is now supported on Blackfin Linux.
1130 * New native configurations
1132 ia64 HP-UX ia64-*-hpux*
1136 Analog Devices, Inc. Blackfin Processor bfin-*
1138 * Ada task switching is now supported on sparc-elf targets when
1139 debugging a program using the Ravenscar Profile. For more information,
1140 see the "Tasking Support when using the Ravenscar Profile" section
1141 in the GDB user manual.
1143 * Guile support was removed.
1145 * New features in the GNU simulator
1147 ** The --map-info flag lists all known core mappings.
1149 ** CFI flashes may be simulated via the "cfi" device.
1151 *** Changes in GDB 7.2
1153 * Shared library support for remote targets by default
1155 When GDB is configured for a generic, non-OS specific target, like
1156 for example, --target=arm-eabi or one of the many *-*-elf targets,
1157 GDB now queries remote stubs for loaded shared libraries using the
1158 `qXfer:libraries:read' packet. Previously, shared library support
1159 was always disabled for such configurations.
1163 ** Argument Dependent Lookup (ADL)
1165 In C++ ADL lookup directs function search to the namespaces of its
1166 arguments even if the namespace has not been imported.
1176 Here the compiler will search for `foo' in the namespace of 'b'
1177 and find A::foo. GDB now supports this. This construct is commonly
1178 used in the Standard Template Library for operators.
1180 ** Improved User Defined Operator Support
1182 In addition to member operators, GDB now supports lookup of operators
1183 defined in a namespace and imported with a `using' directive, operators
1184 defined in the global scope, operators imported implicitly from an
1185 anonymous namespace, and the ADL operators mentioned in the previous
1187 GDB now also supports proper overload resolution for all the previously
1188 mentioned flavors of operators.
1190 ** static const class members
1192 Printing of static const class members that are initialized in the
1193 class definition has been fixed.
1195 * Windows Thread Information Block access.
1197 On Windows targets, GDB now supports displaying the Windows Thread
1198 Information Block (TIB) structure. This structure is visible either
1199 by using the new command `info w32 thread-information-block' or, by
1200 dereferencing the new convenience variable named `$_tlb', a
1201 thread-specific pointer to the TIB. This feature is also supported
1202 when remote debugging using GDBserver.
1204 * Static tracepoints
1206 Static tracepoints are calls in the user program into a tracing
1207 library. One such library is a port of the LTTng kernel tracer to
1208 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1209 When debugging with GDBserver, GDB now supports combining the GDB
1210 tracepoint machinery with such libraries. For example: the user can
1211 use GDB to probe a static tracepoint marker (a call from the user
1212 program into the tracing library) with the new "strace" command (see
1213 "New commands" below). This creates a "static tracepoint" in the
1214 breakpoint list, that can be manipulated with the same feature set
1215 as fast and regular tracepoints. E.g., collect registers, local and
1216 global variables, collect trace state variables, and define
1217 tracepoint conditions. In addition, the user can collect extra
1218 static tracepoint marker specific data, by collecting the new
1219 $_sdata internal variable. When analyzing the trace buffer, you can
1220 inspect $_sdata like any other variable available to GDB. For more
1221 information, see the "Tracepoints" chapter in GDB user manual. New
1222 remote packets have been defined to support static tracepoints, see
1223 the "New remote packets" section below.
1225 * Better reconstruction of tracepoints after disconnected tracing
1227 GDB will attempt to download the original source form of tracepoint
1228 definitions when starting a trace run, and then will upload these
1229 upon reconnection to the target, resulting in a more accurate
1230 reconstruction of the tracepoints that are in use on the target.
1234 You can now exercise direct control over the ways that GDB can
1235 affect your program. For instance, you can disallow the setting of
1236 breakpoints, so that the program can run continuously (assuming
1237 non-stop mode). In addition, the "observer" variable is available
1238 to switch all of the different controls; in observer mode, GDB
1239 cannot affect the target's behavior at all, which is useful for
1240 tasks like diagnosing live systems in the field.
1242 * The new convenience variable $_thread holds the number of the
1245 * New remote packets
1249 Return the address of the Windows Thread Information Block of a given thread.
1253 In response to several of the tracepoint packets, the target may now
1254 also respond with a number of intermediate `qRelocInsn' request
1255 packets before the final result packet, to have GDB handle
1256 relocating an instruction to execute at a different address. This
1257 is particularly useful for stubs that support fast tracepoints. GDB
1258 reports support for this feature in the qSupported packet.
1262 List static tracepoint markers in the target program.
1266 List static tracepoint markers at a given address in the target
1269 qXfer:statictrace:read
1271 Read the static trace data collected (by a `collect $_sdata'
1272 tracepoint action). The remote stub reports support for this packet
1273 to gdb's qSupported query.
1277 Send the current settings of GDB's permission flags.
1281 Send part of the source (textual) form of a tracepoint definition,
1282 which includes location, conditional, and action list.
1284 * The source command now accepts a -s option to force searching for the
1285 script in the source search path even if the script name specifies
1288 * New features in the GDB remote stub, GDBserver
1290 - GDBserver now support tracepoints (including fast tracepoints, and
1291 static tracepoints). The feature is currently supported by the
1292 i386-linux and amd64-linux builds. See the "Tracepoints support
1293 in gdbserver" section in the manual for more information.
1295 GDBserver JIT compiles the tracepoint's conditional agent
1296 expression bytecode into native code whenever possible for low
1297 overhead dynamic tracepoints conditionals. For such tracepoints,
1298 an expression that examines program state is evaluated when the
1299 tracepoint is reached, in order to determine whether to capture
1300 trace data. If the condition is simple and false, processing the
1301 tracepoint finishes very quickly and no data is gathered.
1303 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1304 for static tracepoints support.
1306 - GDBserver now supports x86_64 Windows 64-bit debugging.
1308 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1309 it understands register description.
1311 * The --batch flag now disables pagination and queries.
1313 * X86 general purpose registers
1315 GDB now supports reading/writing byte, word and double-word x86
1316 general purpose registers directly. This means you can use, say,
1317 $ah or $ax to refer, respectively, to the byte register AH and
1318 16-bit word register AX that are actually portions of the 32-bit
1319 register EAX or 64-bit register RAX.
1321 * The `commands' command now accepts a range of breakpoints to modify.
1322 A plain `commands' following a command that creates multiple
1323 breakpoints affects all the breakpoints set by that command. This
1324 applies to breakpoints set by `rbreak', and also applies when a
1325 single `break' command creates multiple breakpoints (e.g.,
1326 breakpoints on overloaded c++ functions).
1328 * The `rbreak' command now accepts a filename specification as part of
1329 its argument, limiting the functions selected by the regex to those
1330 in the specified file.
1332 * Support for remote debugging Windows and SymbianOS shared libraries
1333 from Unix hosts has been improved. Non Windows GDB builds now can
1334 understand target reported file names that follow MS-DOS based file
1335 system semantics, such as file names that include drive letters and
1336 use the backslash character as directory separator. This makes it
1337 possible to transparently use the "set sysroot" and "set
1338 solib-search-path" on Unix hosts to point as host copies of the
1339 target's shared libraries. See the new command "set
1340 target-file-system-kind" described below, and the "Commands to
1341 specify files" section in the user manual for more information.
1345 eval template, expressions...
1346 Convert the values of one or more expressions under the control
1347 of the string template to a command line, and call it.
1349 set target-file-system-kind unix|dos-based|auto
1350 show target-file-system-kind
1351 Set or show the assumed file system kind for target reported file
1354 save breakpoints <filename>
1355 Save all current breakpoint definitions to a file suitable for use
1356 in a later debugging session. To read the saved breakpoint
1357 definitions, use the `source' command.
1359 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1362 info static-tracepoint-markers
1363 Display information about static tracepoint markers in the target.
1365 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1366 Define a static tracepoint by probing a marker at the given
1367 function, line, address, or marker ID.
1371 Enable and disable observer mode.
1373 set may-write-registers on|off
1374 set may-write-memory on|off
1375 set may-insert-breakpoints on|off
1376 set may-insert-tracepoints on|off
1377 set may-insert-fast-tracepoints on|off
1378 set may-interrupt on|off
1379 Set individual permissions for GDB effects on the target. Note that
1380 some of these settings can have undesirable or surprising
1381 consequences, particularly when changed in the middle of a session.
1382 For instance, disabling the writing of memory can prevent
1383 breakpoints from being inserted, cause single-stepping to fail, or
1384 even crash your program, if you disable after breakpoints have been
1385 inserted. However, GDB should not crash.
1387 set record memory-query on|off
1388 show record memory-query
1389 Control whether to stop the inferior if memory changes caused
1390 by an instruction cannot be recorded.
1395 The disassemble command now supports "start,+length" form of two arguments.
1399 ** GDB now provides a new directory location, called the python directory,
1400 where Python scripts written for GDB can be installed. The location
1401 of that directory is <data-directory>/python, where <data-directory>
1402 is the GDB data directory. For more details, see section `Scripting
1403 GDB using Python' in the manual.
1405 ** The GDB Python API now has access to breakpoints, symbols, symbol
1406 tables, program spaces, inferiors, threads and frame's code blocks.
1407 Additionally, GDB Parameters can now be created from the API, and
1408 manipulated via set/show in the CLI.
1410 ** New functions gdb.target_charset, gdb.target_wide_charset,
1411 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1413 ** New exception gdb.GdbError.
1415 ** Pretty-printers are now also looked up in the current program space.
1417 ** Pretty-printers can now be individually enabled and disabled.
1419 ** GDB now looks for names of Python scripts to auto-load in a
1420 special section named `.debug_gdb_scripts', in addition to looking
1421 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1423 * Tracepoint actions were unified with breakpoint commands. In particular,
1424 there are no longer differences in "info break" output for breakpoints and
1425 tracepoints and the "commands" command can be used for both tracepoints and
1426 regular breakpoints.
1430 ARM Symbian arm*-*-symbianelf*
1432 * D language support.
1433 GDB now supports debugging programs written in the D programming
1436 * GDB now supports the extended ptrace interface for PowerPC which is
1437 available since Linux kernel version 2.6.34. This automatically enables
1438 any hardware breakpoints and additional hardware watchpoints available in
1439 the processor. The old ptrace interface exposes just one hardware
1440 watchpoint and no hardware breakpoints.
1442 * GDB is now able to use the Data Value Compare (DVC) register available on
1443 embedded PowerPC processors to implement in hardware simple watchpoint
1444 conditions of the form:
1446 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1448 This works in native GDB running on Linux kernels with the extended ptrace
1449 interface mentioned above.
1451 *** Changes in GDB 7.1
1455 ** Namespace Support
1457 GDB now supports importing of namespaces in C++. This enables the
1458 user to inspect variables from imported namespaces. Support for
1459 namepace aliasing has also been added. So, if a namespace is
1460 aliased in the current scope (e.g. namepace C=A; ) the user can
1461 print variables using the alias (e.g. (gdb) print C::x).
1465 All known bugs relating to the printing of virtual base class were
1466 fixed. It is now possible to call overloaded static methods using a
1471 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1472 and reinterpret_cast<> are now handled by the C++ expression parser.
1476 Xilinx MicroBlaze microblaze-*-*
1481 Xilinx MicroBlaze microblaze
1484 * Multi-program debugging.
1486 GDB now has support for multi-program (a.k.a. multi-executable or
1487 multi-exec) debugging. This allows for debugging multiple inferiors
1488 simultaneously each running a different program under the same GDB
1489 session. See "Debugging Multiple Inferiors and Programs" in the
1490 manual for more information. This implied some user visible changes
1491 in the multi-inferior support. For example, "info inferiors" now
1492 lists inferiors that are not running yet or that have exited
1493 already. See also "New commands" and "New options" below.
1495 * New tracing features
1497 GDB's tracepoint facility now includes several new features:
1499 ** Trace state variables
1501 GDB tracepoints now include support for trace state variables, which
1502 are variables managed by the target agent during a tracing
1503 experiment. They are useful for tracepoints that trigger each
1504 other, so for instance one tracepoint can count hits in a variable,
1505 and then a second tracepoint has a condition that is true when the
1506 count reaches a particular value. Trace state variables share the
1507 $-syntax of GDB convenience variables, and can appear in both
1508 tracepoint actions and condition expressions. Use the "tvariable"
1509 command to create, and "info tvariables" to view; see "Trace State
1510 Variables" in the manual for more detail.
1514 GDB now includes an option for defining fast tracepoints, which
1515 targets may implement more efficiently, such as by installing a jump
1516 into the target agent rather than a trap instruction. The resulting
1517 speedup can be by two orders of magnitude or more, although the
1518 tradeoff is that some program locations on some target architectures
1519 might not allow fast tracepoint installation, for instance if the
1520 instruction to be replaced is shorter than the jump. To request a
1521 fast tracepoint, use the "ftrace" command, with syntax identical to
1522 the regular trace command.
1524 ** Disconnected tracing
1526 It is now possible to detach GDB from the target while it is running
1527 a trace experiment, then reconnect later to see how the experiment
1528 is going. In addition, a new variable disconnected-tracing lets you
1529 tell the target agent whether to continue running a trace if the
1530 connection is lost unexpectedly.
1534 GDB now has the ability to save the trace buffer into a file, and
1535 then use that file as a target, similarly to you can do with
1536 corefiles. You can select trace frames, print data that was
1537 collected in them, and use tstatus to display the state of the
1538 tracing run at the moment that it was saved. To create a trace
1539 file, use "tsave <filename>", and to use it, do "target tfile
1542 ** Circular trace buffer
1544 You can ask the target agent to handle the trace buffer as a
1545 circular buffer, discarding the oldest trace frames to make room for
1546 newer ones, by setting circular-trace-buffer to on. This feature may
1547 not be available for all target agents.
1552 The disassemble command, when invoked with two arguments, now requires
1553 the arguments to be comma-separated.
1556 The info variables command now displays variable definitions. Files
1557 which only declare a variable are not shown.
1560 The source command is now capable of sourcing Python scripts.
1561 This feature is dependent on the debugger being build with Python
1564 Related to this enhancement is also the introduction of a new command
1565 "set script-extension" (see below).
1567 * New commands (for set/show, see "New options" below)
1569 record save [<FILENAME>]
1570 Save a file (in core file format) containing the process record
1571 execution log for replay debugging at a later time.
1573 record restore <FILENAME>
1574 Restore the process record execution log that was saved at an
1575 earlier time, for replay debugging.
1577 add-inferior [-copies <N>] [-exec <FILENAME>]
1580 clone-inferior [-copies <N>] [ID]
1581 Make a new inferior ready to execute the same program another
1582 inferior has loaded.
1587 maint info program-spaces
1588 List the program spaces loaded into GDB.
1590 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1591 show remote interrupt-sequence
1592 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1593 as the sequence to the remote target in order to interrupt the execution.
1594 Ctrl-C is a default. Some system prefers BREAK which is high level of
1595 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1596 Magic SysRq g. It is BREAK signal and character 'g'.
1598 set remote interrupt-on-connect [on | off]
1599 show remote interrupt-on-connect
1600 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1601 remote target when gdb connects to it. This is needed when you debug
1604 set remotebreak [on | off]
1606 Deprecated. Use "set/show remote interrupt-sequence" instead.
1608 tvariable $NAME [ = EXP ]
1609 Create or modify a trace state variable.
1612 List trace state variables and their values.
1614 delete tvariable $NAME ...
1615 Delete one or more trace state variables.
1618 Evaluate the given expressions without collecting anything into the
1619 trace buffer. (Valid in tracepoint actions only.)
1621 ftrace FN / FILE:LINE / *ADDR
1622 Define a fast tracepoint at the given function, line, or address.
1624 * New expression syntax
1626 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1627 GDB now parses 0b101010 identically with 42.
1631 set follow-exec-mode new|same
1632 show follow-exec-mode
1633 Control whether GDB reuses the same inferior across an exec call or
1634 creates a new one. This is useful to be able to restart the old
1635 executable after the inferior having done an exec call.
1637 set default-collect EXPR, ...
1638 show default-collect
1639 Define a list of expressions to be collected at each tracepoint.
1640 This is a useful way to ensure essential items are not overlooked,
1641 such as registers or a critical global variable.
1643 set disconnected-tracing
1644 show disconnected-tracing
1645 If set to 1, the target is instructed to continue tracing if it
1646 loses its connection to GDB. If 0, the target is to stop tracing
1649 set circular-trace-buffer
1650 show circular-trace-buffer
1651 If set to on, the target is instructed to use a circular trace buffer
1652 and discard the oldest trace frames instead of stopping the trace due
1653 to a full trace buffer. If set to off, the trace stops when the buffer
1654 fills up. Some targets may not support this.
1656 set script-extension off|soft|strict
1657 show script-extension
1658 If set to "off", the debugger does not perform any script language
1659 recognition, and all sourced files are assumed to be GDB scripts.
1660 If set to "soft" (the default), files are sourced according to
1661 filename extension, falling back to GDB scripts if the first
1663 If set to "strict", files are sourced according to filename extension.
1665 set ada trust-PAD-over-XVS on|off
1666 show ada trust-PAD-over-XVS
1667 If off, activate a workaround against a bug in the debugging information
1668 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1669 the GCC sources for more information about the GNAT encoding and
1670 PAD types in particular). It is always safe to set this option to
1671 off, but this introduces a slight performance penalty. The default
1674 * Python API Improvements
1676 ** GDB provides the new class gdb.LazyString. This is useful in
1677 some pretty-printing cases. The new method gdb.Value.lazy_string
1678 provides a simple way to create objects of this type.
1680 ** The fields returned by gdb.Type.fields now have an
1681 `is_base_class' attribute.
1683 ** The new method gdb.Type.range returns the range of an array type.
1685 ** The new method gdb.parse_and_eval can be used to parse and
1686 evaluate an expression.
1688 * New remote packets
1691 Define a trace state variable.
1694 Get the current value of a trace state variable.
1697 Set desired tracing behavior upon disconnection.
1700 Set the trace buffer to be linear or circular.
1703 Get data about the tracepoints currently in use.
1707 Process record now works correctly with hardware watchpoints.
1709 Multiple bug fixes have been made to the mips-irix port, making it
1710 much more reliable. In particular:
1711 - Debugging threaded applications is now possible again. Previously,
1712 GDB would hang while starting the program, or while waiting for
1713 the program to stop at a breakpoint.
1714 - Attaching to a running process no longer hangs.
1715 - An error occurring while loading a core file has been fixed.
1716 - Changing the value of the PC register now works again. This fixes
1717 problems observed when using the "jump" command, or when calling
1718 a function from GDB, or even when assigning a new value to $pc.
1719 - With the "finish" and "return" commands, the return value for functions
1720 returning a small array is now correctly printed.
1721 - It is now possible to break on shared library code which gets executed
1722 during a shared library init phase (code executed while executing
1723 their .init section). Previously, the breakpoint would have no effect.
1724 - GDB is now able to backtrace through the signal handler for
1725 non-threaded programs.
1727 PIE (Position Independent Executable) programs debugging is now supported.
1728 This includes debugging execution of PIC (Position Independent Code) shared
1729 libraries although for that, it should be possible to run such libraries as an
1732 *** Changes in GDB 7.0
1734 * GDB now has an interface for JIT compilation. Applications that
1735 dynamically generate code can create symbol files in memory and register
1736 them with GDB. For users, the feature should work transparently, and
1737 for JIT developers, the interface is documented in the GDB manual in the
1738 "JIT Compilation Interface" chapter.
1740 * Tracepoints may now be conditional. The syntax is as for
1741 breakpoints; either an "if" clause appended to the "trace" command,
1742 or the "condition" command is available. GDB sends the condition to
1743 the target for evaluation using the same bytecode format as is used
1744 for tracepoint actions.
1746 * The disassemble command now supports: an optional /r modifier, print the
1747 raw instructions in hex as well as in symbolic form, and an optional /m
1748 modifier to print mixed source+assembly.
1750 * Process record and replay
1752 In a architecture environment that supports ``process record and
1753 replay'', ``process record and replay'' target can record a log of
1754 the process execution, and replay it with both forward and reverse
1757 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1758 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1759 set execution-direction {forward|reverse}, for targets that support
1762 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1763 feature is available with a native GDB running on kernel version
1766 * GDB now has support for multi-byte and wide character sets on the
1767 target. Strings whose character type is wchar_t, char16_t, or
1768 char32_t are now correctly printed. GDB supports wide- and unicode-
1769 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1770 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1771 `printf'. This feature requires iconv to work properly; if your
1772 system does not have a working iconv, GDB can use GNU libiconv. See
1773 the installation instructions for more information.
1775 * GDB now supports automatic retrieval of shared library files from
1776 remote targets. To use this feature, specify a system root that begins
1777 with the `remote:' prefix, either via the `set sysroot' command or via
1778 the `--with-sysroot' configure-time option.
1780 * "info sharedlibrary" now takes an optional regex of libraries to show,
1781 and it now reports if a shared library has no debugging information.
1783 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1784 now complete on file names.
1786 * When completing in expressions, gdb will attempt to limit
1787 completions to allowable structure or union fields, where appropriate.
1788 For instance, consider:
1790 # struct example { int f1; double f2; };
1791 # struct example variable;
1794 If the user types TAB at the end of this command line, the available
1795 completions will be "f1" and "f2".
1797 * Inlined functions are now supported. They show up in backtraces, and
1798 the "step", "next", and "finish" commands handle them automatically.
1800 * GDB now supports the token-splicing (##) and stringification (#)
1801 operators when expanding macros. It also supports variable-arity
1804 * GDB now supports inspecting extra signal information, exported by
1805 the new $_siginfo convenience variable. The feature is currently
1806 implemented on linux ARM, i386 and amd64.
1808 * GDB can now display the VFP floating point registers and NEON vector
1809 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1810 can provide these registers (requires Linux 2.6.30 or later). Remote
1811 and simulator targets may also provide them.
1813 * New remote packets
1816 Search memory for a sequence of bytes.
1819 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1820 operation over reliable transport links. Use of this packet is
1821 controlled by the `set remote noack-packet' command.
1824 Kill the process with the specified process ID. Use this in preference
1825 to `k' when multiprocess protocol extensions are supported.
1828 Obtains additional operating system information
1832 Read or write additional signal information.
1834 * Removed remote protocol undocumented extension
1836 An undocumented extension to the remote protocol's `S' stop reply
1837 packet that permited the stub to pass a process id was removed.
1838 Remote servers should use the `T' stop reply packet instead.
1840 * GDB now supports multiple function calling conventions according to the
1841 DWARF-2 DW_AT_calling_convention function attribute.
1843 * The SH target utilizes the aforementioned change to distinguish between gcc
1844 and Renesas calling convention. It also adds the new CLI commands
1845 `set/show sh calling-convention'.
1847 * GDB can now read compressed debug sections, as produced by GNU gold
1848 with the --compress-debug-sections=zlib flag.
1850 * 64-bit core files are now supported on AIX.
1852 * Thread switching is now supported on Tru64.
1854 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1855 which will be allocated using malloc later in program execution.
1857 * The qXfer:libraries:read remote procotol packet now allows passing a
1858 list of section offsets.
1860 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1861 conditions handling signals delivered during attach or thread creation
1862 have also been fixed.
1864 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1865 From the user's standpoint, all unqualified instances of True and False
1866 are treated as the standard definitions, regardless of context.
1868 * GDB now parses C++ symbol and type names more flexibly. For
1871 template<typename T> class C { };
1874 GDB will now correctly handle all of:
1876 ptype C<char const *>
1877 ptype C<char const*>
1878 ptype C<const char *>
1879 ptype C<const char*>
1881 * New features in the GDB remote stub, gdbserver
1883 - The "--wrapper" command-line argument tells gdbserver to use a
1884 wrapper program to launch programs for debugging.
1886 - On PowerPC and S/390 targets, it is now possible to use a single
1887 gdbserver executable to debug both 32-bit and 64-bit programs.
1888 (This requires gdbserver itself to be built as a 64-bit executable.)
1890 - gdbserver uses the new noack protocol mode for TCP connections to
1891 reduce communications latency, if also supported and enabled in GDB.
1893 - Support for the sparc64-linux-gnu target is now included in
1896 - The amd64-linux build of gdbserver now supports debugging both
1897 32-bit and 64-bit programs.
1899 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1900 now support hardware watchpoints, and will use them automatically
1905 GDB now has support for scripting using Python. Whether this is
1906 available is determined at configure time.
1908 New GDB commands can now be written in Python.
1910 * Ada tasking support
1912 Ada tasks can now be inspected in GDB. The following commands have
1916 Print the list of Ada tasks.
1918 Print detailed information about task number N.
1920 Print the task number of the current task.
1922 Switch the context of debugging to task number N.
1924 * Support for user-defined prefixed commands. The "define" command can
1925 add new commands to existing prefixes, e.g. "target".
1927 * Multi-inferior, multi-process debugging.
1929 GDB now has generalized support for multi-inferior debugging. See
1930 "Debugging Multiple Inferiors" in the manual for more information.
1931 Although availability still depends on target support, the command
1932 set is more uniform now. The GNU/Linux specific multi-forks support
1933 has been migrated to this new framework. This implied some user
1934 visible changes; see "New commands" and also "Removed commands"
1937 * Target descriptions can now describe the target OS ABI. See the
1938 "Target Description Format" section in the user manual for more
1941 * Target descriptions can now describe "compatible" architectures
1942 to indicate that the target can execute applications for a different
1943 architecture in addition to those for the main target architecture.
1944 See the "Target Description Format" section in the user manual for
1947 * Multi-architecture debugging.
1949 GDB now includes general supports for debugging applications on
1950 hybrid systems that use more than one single processor architecture
1951 at the same time. Each such hybrid architecture still requires
1952 specific support to be added. The only hybrid architecture supported
1953 in this version of GDB is the Cell Broadband Engine.
1955 * GDB now supports integrated debugging of Cell/B.E. applications that
1956 use both the PPU and SPU architectures. To enable support for hybrid
1957 Cell/B.E. debugging, you need to configure GDB to support both the
1958 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1959 --enable-targets configure option.
1961 * Non-stop mode debugging.
1963 For some targets, GDB now supports an optional mode of operation in
1964 which you can examine stopped threads while other threads continue
1965 to execute freely. This is referred to as non-stop mode, with the
1966 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1967 section in the user manual for more information.
1969 To be able to support remote non-stop debugging, a remote stub needs
1970 to implement the non-stop mode remote protocol extensions, as
1971 described in the "Remote Non-Stop" section of the user manual. The
1972 GDB remote stub, gdbserver, has been adjusted to support these
1973 extensions on linux targets.
1975 * New commands (for set/show, see "New options" below)
1977 catch syscall [NAME(S) | NUMBER(S)]
1978 Catch system calls. Arguments, which should be names of system
1979 calls or their numbers, mean catch only those syscalls. Without
1980 arguments, every syscall will be caught. When the inferior issues
1981 any of the specified syscalls, GDB will stop and announce the system
1982 call, both when it is called and when its call returns. This
1983 feature is currently available with a native GDB running on the
1984 Linux Kernel, under the following architectures: x86, x86_64,
1985 PowerPC and PowerPC64.
1987 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1989 Search memory for a sequence of bytes.
1991 maint set python print-stack
1992 maint show python print-stack
1993 Show a stack trace when an error is encountered in a Python script.
1996 Invoke CODE by passing it to the Python interpreter.
2001 These allow macros to be defined, undefined, and listed
2005 Show operating system information about processes.
2008 List the inferiors currently under GDB's control.
2011 Switch focus to inferior number NUM.
2014 Detach from inferior number NUM.
2017 Kill inferior number NUM.
2021 set spu stop-on-load
2022 show spu stop-on-load
2023 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2025 set spu auto-flush-cache
2026 show spu auto-flush-cache
2027 Control whether to automatically flush the software-managed cache
2028 during Cell/B.E. debugging.
2030 set sh calling-convention
2031 show sh calling-convention
2032 Control the calling convention used when calling SH target functions.
2035 show debug timestamp
2036 Control display of timestamps with GDB debugging output.
2038 set disassemble-next-line
2039 show disassemble-next-line
2040 Control display of disassembled source lines or instructions when
2043 set remote noack-packet
2044 show remote noack-packet
2045 Set/show the use of remote protocol QStartNoAckMode packet. See above
2046 under "New remote packets."
2048 set remote query-attached-packet
2049 show remote query-attached-packet
2050 Control use of remote protocol `qAttached' (query-attached) packet.
2052 set remote read-siginfo-object
2053 show remote read-siginfo-object
2054 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2057 set remote write-siginfo-object
2058 show remote write-siginfo-object
2059 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2062 set remote reverse-continue
2063 show remote reverse-continue
2064 Control use of remote protocol 'bc' (reverse-continue) packet.
2066 set remote reverse-step
2067 show remote reverse-step
2068 Control use of remote protocol 'bs' (reverse-step) packet.
2070 set displaced-stepping
2071 show displaced-stepping
2072 Control displaced stepping mode. Displaced stepping is a way to
2073 single-step over breakpoints without removing them from the debuggee.
2074 Also known as "out-of-line single-stepping".
2077 show debug displaced
2078 Control display of debugging info for displaced stepping.
2080 maint set internal-error
2081 maint show internal-error
2082 Control what GDB does when an internal error is detected.
2084 maint set internal-warning
2085 maint show internal-warning
2086 Control what GDB does when an internal warning is detected.
2091 Use a wrapper program to launch programs for debugging.
2093 set multiple-symbols (all|ask|cancel)
2094 show multiple-symbols
2095 The value of this variable can be changed to adjust the debugger behavior
2096 when an expression or a breakpoint location contains an ambiguous symbol
2097 name (an overloaded function name, for instance).
2099 set breakpoint always-inserted
2100 show breakpoint always-inserted
2101 Keep breakpoints always inserted in the target, as opposed to inserting
2102 them when resuming the target, and removing them when the target stops.
2103 This option can improve debugger performance on slow remote targets.
2105 set arm fallback-mode (arm|thumb|auto)
2106 show arm fallback-mode
2107 set arm force-mode (arm|thumb|auto)
2109 These commands control how ARM GDB determines whether instructions
2110 are ARM or Thumb. The default for both settings is auto, which uses
2111 the current CPSR value for instructions without symbols; previous
2112 versions of GDB behaved as if "set arm fallback-mode arm".
2114 set disable-randomization
2115 show disable-randomization
2116 Standalone programs run with the virtual address space randomization enabled
2117 by default on some platforms. This option keeps the addresses stable across
2118 multiple debugging sessions.
2122 Control whether other threads are stopped or not when some thread hits
2127 Requests that asynchronous execution is enabled in the target, if available.
2128 In this case, it's possible to resume target in the background, and interact
2129 with GDB while the target is running. "show target-async" displays the
2130 current state of asynchronous execution of the target.
2132 set target-wide-charset
2133 show target-wide-charset
2134 The target-wide-charset is the name of the character set that GDB
2135 uses when printing characters whose type is wchar_t.
2137 set tcp auto-retry (on|off)
2139 set tcp connect-timeout
2140 show tcp connect-timeout
2141 These commands allow GDB to retry failed TCP connections to a remote stub
2142 with a specified timeout period; this is useful if the stub is launched
2143 in parallel with GDB but may not be ready to accept connections immediately.
2145 set libthread-db-search-path
2146 show libthread-db-search-path
2147 Control list of directories which GDB will search for appropriate
2150 set schedule-multiple (on|off)
2151 show schedule-multiple
2152 Allow GDB to resume all threads of all processes or only threads of
2153 the current process.
2157 Use more aggressive caching for accesses to the stack. This improves
2158 performance of remote debugging (particularly backtraces) without
2159 affecting correctness.
2161 set interactive-mode (on|off|auto)
2162 show interactive-mode
2163 Control whether GDB runs in interactive mode (on) or not (off).
2164 When in interactive mode, GDB waits for the user to answer all
2165 queries. Otherwise, GDB does not wait and assumes the default
2166 answer. When set to auto (the default), GDB determines which
2167 mode to use based on the stdin settings.
2172 For program forks, this is replaced by the new more generic `info
2173 inferiors' command. To list checkpoints, you can still use the
2174 `info checkpoints' command, which was an alias for the `info forks'
2178 Replaced by the new `inferior' command. To switch between
2179 checkpoints, you can still use the `restart' command, which was an
2180 alias for the `fork' command.
2183 This is removed, since some targets don't have a notion of
2184 processes. To switch between processes, you can still use the
2185 `inferior' command using GDB's own inferior number.
2188 For program forks, this is replaced by the new more generic `kill
2189 inferior' command. To delete a checkpoint, you can still use the
2190 `delete checkpoint' command, which was an alias for the `delete
2194 For program forks, this is replaced by the new more generic `detach
2195 inferior' command. To detach a checkpoint, you can still use the
2196 `detach checkpoint' command, which was an alias for the `detach
2199 * New native configurations
2201 x86/x86_64 Darwin i[34567]86-*-darwin*
2203 x86_64 MinGW x86_64-*-mingw*
2207 Lattice Mico32 lm32-*
2208 x86 DICOS i[34567]86-*-dicos*
2209 x86_64 DICOS x86_64-*-dicos*
2212 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2213 (mingw32ce) debugging.
2219 These commands were actually not implemented on any target.
2221 *** Changes in GDB 6.8
2223 * New native configurations
2225 NetBSD/hppa hppa*-*netbsd*
2226 Xtensa GNU/Linux xtensa*-*-linux*
2230 NetBSD/hppa hppa*-*-netbsd*
2231 Xtensa GNU/Lunux xtensa*-*-linux*
2233 * Change in command line behavior -- corefiles vs. process ids.
2235 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2236 attaching to process NUMBER fails, GDB no longer attempts to open a
2237 core file named NUMBER. Attaching to a program using the -c option
2238 is no longer supported. Instead, use the '-p' or '--pid' options.
2240 * GDB can now be built as a native debugger for debugging Windows x86
2241 (mingw32) Portable Executable (PE) programs.
2243 * Pending breakpoints no longer change their number when their address
2246 * GDB now supports breakpoints with multiple locations,
2247 including breakpoints on C++ constructors, inside C++ templates,
2248 and in inlined functions.
2250 * GDB's ability to debug optimized code has been improved. GDB more
2251 accurately identifies function bodies and lexical blocks that occupy
2252 more than one contiguous range of addresses.
2254 * Target descriptions can now describe registers for PowerPC.
2256 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2257 registers on PowerPC targets.
2259 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2260 targets even when the libthread_db library is not available.
2262 * The GDB remote stub, gdbserver, now supports the new file transfer
2263 commands (remote put, remote get, and remote delete).
2265 * The GDB remote stub, gdbserver, now supports run and attach in
2266 extended-remote mode.
2268 * hppa*64*-*-hpux11* target broken
2269 The debugger is unable to start a program and fails with the following
2270 error: "Error trying to get information about dynamic linker".
2271 The gdb-6.7 release is also affected.
2273 * GDB now supports the --enable-targets= configure option to allow
2274 building a single GDB executable that supports multiple remote
2275 target architectures.
2277 * GDB now supports debugging C and C++ programs which use the
2278 Decimal Floating Point extension. In addition, the PowerPC target
2279 now has a set of pseudo-registers to inspect decimal float values
2280 stored in two consecutive float registers.
2282 * The -break-insert MI command can optionally create pending
2285 * Improved support for debugging Ada
2286 Many improvements to the Ada language support have been made. These
2288 - Better support for Ada2005 interface types
2289 - Improved handling of arrays and slices in general
2290 - Better support for Taft-amendment types
2291 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2293 - Improved command completion in Ada
2296 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2301 set print frame-arguments (all|scalars|none)
2302 show print frame-arguments
2303 The value of this variable can be changed to control which argument
2304 values should be printed by the debugger when displaying a frame.
2309 Transfer files to and from a remote target, and delete remote files.
2316 Transfer files to and from a remote target, and delete remote files.
2318 * New remote packets
2325 Open, close, read, write, and delete files on the remote system.
2328 Attach to an existing process on the remote system, in extended-remote
2332 Run a new process on the remote system, in extended-remote mode.
2334 *** Changes in GDB 6.7
2336 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2337 bfd, libiberty and opcodes, as revealed by static analysis donated by
2338 Coverity, Inc. (http://scan.coverity.com).
2340 * When looking up multiply-defined global symbols, GDB will now prefer the
2341 symbol definition in the current shared library if it was built using the
2342 -Bsymbolic linker option.
2344 * When the Text User Interface (TUI) is not configured, GDB will now
2345 recognize the -tui command-line option and print a message that the TUI
2348 * The GDB remote stub, gdbserver, now has lower overhead for high
2349 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2351 * GDB for MIPS targets now autodetects whether a remote target provides
2352 32-bit or 64-bit register values.
2354 * Support for C++ member pointers has been improved.
2356 * GDB now understands XML target descriptions, which specify the
2357 target's overall architecture. GDB can read a description from
2358 a local file or over the remote serial protocol.
2360 * Vectors of single-byte data use a new integer type which is not
2361 automatically displayed as character or string data.
2363 * The /s format now works with the print command. It displays
2364 arrays of single-byte integers and pointers to single-byte integers
2367 * Target descriptions can now describe target-specific registers,
2368 for architectures which have implemented the support (currently
2369 only ARM, M68K, and MIPS).
2371 * GDB and the GDB remote stub, gdbserver, now support the XScale
2374 * The GDB remote stub, gdbserver, has been updated to support
2375 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2376 has been rewritten to use the standard GDB remote protocol.
2378 * GDB can now step into C++ functions which are called through thunks.
2380 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2382 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2383 layout. It also supports a TextSeg= and DataSeg= response when only
2384 segment base addresses (rather than offsets) are available.
2386 * The /i format now outputs any trailing branch delay slot instructions
2387 immediately following the last instruction within the count specified.
2389 * The GDB remote protocol "T" stop reply packet now supports a
2390 "library" response. Combined with the new "qXfer:libraries:read"
2391 packet, this response allows GDB to debug shared libraries on targets
2392 where the operating system manages the list of loaded libraries (e.g.
2393 Windows and SymbianOS).
2395 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2396 (DLLs) on Windows and Windows CE targets.
2398 * GDB now supports a faster verification that a .debug file matches its binary
2399 according to its build-id signature, if the signature is present.
2405 Enable or disable hardware flow control (RTS/CTS) on the serial port
2406 when debugging using remote targets.
2408 set mem inaccessible-by-default
2409 show mem inaccessible-by-default
2410 If the target supplies a memory map, for instance via the remote
2411 protocol's "qXfer:memory-map:read" packet, setting this variable
2412 prevents GDB from accessing memory outside the memory map. This
2413 is useful for targets with memory mapped registers or which react
2414 badly to accesses of unmapped address space.
2416 set breakpoint auto-hw
2417 show breakpoint auto-hw
2418 If the target supplies a memory map, for instance via the remote
2419 protocol's "qXfer:memory-map:read" packet, setting this variable
2420 lets GDB use hardware breakpoints automatically for memory regions
2421 where it can not use software breakpoints. This covers both the
2422 "break" command and internal breakpoints used for other commands
2423 including "next" and "finish".
2426 catch exception unhandled
2427 Stop the program execution when Ada exceptions are raised.
2430 Stop the program execution when an Ada assertion failed.
2434 Set an alternate system root for target files. This is a more
2435 general version of "set solib-absolute-prefix", which is now
2436 an alias to "set sysroot".
2439 Provide extended SPU facility status information. This set of
2440 commands is available only when debugging the Cell/B.E. SPU
2443 * New native configurations
2445 OpenBSD/sh sh*-*openbsd*
2448 unset tdesc filename
2450 Use the specified local file as an XML target description, and do
2451 not query the target for its built-in description.
2455 OpenBSD/sh sh*-*-openbsd*
2456 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2457 Toshiba Media Processor mep-elf
2459 * New remote packets
2462 Ignore the specified signals; pass them directly to the debugged program
2463 without stopping other threads or reporting them to GDB.
2465 qXfer:features:read:
2466 Read an XML target description from the target, which describes its
2471 Read or write contents of an spufs file on the target system. These
2472 packets are available only on the Cell/B.E. SPU architecture.
2474 qXfer:libraries:read:
2475 Report the loaded shared libraries. Combined with new "T" packet
2476 response, this packet allows GDB to debug shared libraries on
2477 targets where the operating system manages the list of loaded
2478 libraries (e.g. Windows and SymbianOS).
2482 Support for these obsolete configurations has been removed.
2490 i[34567]86-*-lynxos*
2491 i[34567]86-*-netware*
2492 i[34567]86-*-sco3.2v5*
2493 i[34567]86-*-sco3.2v4*
2495 i[34567]86-*-sysv4.2*
2498 i[34567]86-*-unixware2*
2499 i[34567]86-*-unixware*
2508 * Other removed features
2515 Various m68k-only ROM monitors.
2522 Various Renesas ROM monitors and debugging interfaces for SH and
2527 Support for a Macraigor serial interface to on-chip debugging.
2528 GDB does not directly support the newer parallel or USB
2533 A debug information format. The predecessor to DWARF 2 and
2534 DWARF 3, which are still supported.
2536 Support for the HP aCC compiler on HP-UX/PA-RISC
2538 SOM-encapsulated symbolic debugging information, automatic
2539 invocation of pxdb, and the aCC custom C++ ABI. This does not
2540 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2541 with aCC can still be debugged on an assembly level.
2543 MIPS ".pdr" sections
2545 A MIPS-specific format used to describe stack frame layout
2546 in debugging information.
2550 GDB could work with an older version of Guile to debug
2551 the interpreter and Scheme programs running in it.
2553 set mips stack-arg-size
2554 set mips saved-gpreg-size
2556 Use "set mips abi" to control parameter passing for MIPS.
2558 *** Changes in GDB 6.6
2563 Cell Broadband Engine SPU spu-elf
2565 * GDB can now be configured as a cross-debugger targeting native Windows
2566 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2567 running on a Windows system over TCP/IP to debug Windows programs.
2569 * The GDB remote stub, gdbserver, has been updated to support Windows and
2570 Cygwin debugging. Both single-threaded and multi-threaded programs are
2573 * The "set trust-readonly-sections" command works again. This command was
2574 broken in GDB 6.3, 6.4, and 6.5.
2576 * The "load" command now supports writing to flash memory, if the remote
2577 stub provides the required support.
2579 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2580 longer requires symbolic debug information (e.g. DWARF-2).
2585 unset substitute-path
2586 show substitute-path
2587 Manage a list of substitution rules that GDB uses to rewrite the name
2588 of the directories where the sources are located. This can be useful
2589 for instance when the sources were moved to a different location
2590 between compilation and debugging.
2594 Print each CLI command as it is executed. Each command is prefixed with
2595 a number of `+' symbols representing the nesting depth.
2596 The source command now has a `-v' option to enable the same feature.
2600 The ARM Demon monitor support (RDP protocol, "target rdp").
2602 Kernel Object Display, an embedded debugging feature which only worked with
2603 an obsolete version of Cisco IOS.
2605 The 'set download-write-size' and 'show download-write-size' commands.
2607 * New remote packets
2610 Tell a stub about GDB client features, and request remote target features.
2611 The first feature implemented is PacketSize, which allows the target to
2612 specify the size of packets it can handle - to minimize the number of
2613 packets required and improve performance when connected to a remote
2617 Fetch an OS auxilliary vector from the remote stub. This packet is a
2618 more efficient replacement for qPart:auxv:read.
2620 qXfer:memory-map:read:
2621 Fetch a memory map from the remote stub, including information about
2622 RAM, ROM, and flash memory devices.
2627 Erase and program a flash memory device.
2629 * Removed remote packets
2632 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2633 used it, and only gdbserver implemented it.
2635 *** Changes in GDB 6.5
2639 Renesas M32C/M16C m32c-elf
2641 Morpho Technologies ms1 ms1-elf
2645 init-if-undefined Initialize a convenience variable, but
2646 only if it doesn't already have a value.
2648 The following commands are presently only implemented for native GNU/Linux:
2650 checkpoint Save a snapshot of the program state.
2652 restart <n> Return the program state to a
2653 previously saved state.
2655 info checkpoints List currently saved checkpoints.
2657 delete-checkpoint <n> Delete a previously saved checkpoint.
2659 set|show detach-on-fork Tell gdb whether to detach from a newly
2660 forked process, or to keep debugging it.
2662 info forks List forks of the user program that
2663 are available to be debugged.
2665 fork <n> Switch to debugging one of several
2666 forks of the user program that are
2667 available to be debugged.
2669 delete-fork <n> Delete a fork from the list of forks
2670 that are available to be debugged (and
2671 kill the forked process).
2673 detach-fork <n> Delete a fork from the list of forks
2674 that are available to be debugged (and
2675 allow the process to continue).
2679 Morpho Technologies ms2 ms1-elf
2681 * Improved Windows host support
2683 GDB now builds as a cross debugger hosted on i686-mingw32, including
2684 native console support, and remote communications using either
2685 network sockets or serial ports.
2687 * Improved Modula-2 language support
2689 GDB can now print most types in the Modula-2 syntax. This includes:
2690 basic types, set types, record types, enumerated types, range types,
2691 pointer types and ARRAY types. Procedure var parameters are correctly
2692 printed and hexadecimal addresses and character constants are also
2693 written in the Modula-2 syntax. Best results can be obtained by using
2694 GNU Modula-2 together with the -gdwarf-2 command line option.
2698 The ARM rdi-share module.
2700 The Netware NLM debug server.
2702 *** Changes in GDB 6.4
2704 * New native configurations
2706 OpenBSD/arm arm*-*-openbsd*
2707 OpenBSD/mips64 mips64-*-openbsd*
2711 Morpho Technologies ms1 ms1-elf
2713 * New command line options
2715 --batch-silent As for --batch, but totally silent.
2716 --return-child-result The debugger will exist with the same value
2717 the child (debugged) program exited with.
2718 --eval-command COMMAND, -ex COMMAND
2719 Execute a single GDB CLI command. This may be
2720 specified multiple times and in conjunction
2721 with the --command (-x) option.
2723 * Deprecated commands removed
2725 The following commands, that were deprecated in 2000, have been
2729 set|show arm disassembly-flavor set|show arm disassembler
2730 othernames set arm disassembler
2731 set|show remotedebug set|show debug remote
2732 set|show archdebug set|show debug arch
2733 set|show eventdebug set|show debug event
2736 * New BSD user-level threads support
2738 It is now possible to debug programs using the user-level threads
2739 library on OpenBSD and FreeBSD. Currently supported (target)
2742 FreeBSD/amd64 x86_64-*-freebsd*
2743 FreeBSD/i386 i386-*-freebsd*
2744 OpenBSD/i386 i386-*-openbsd*
2746 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2747 are not yet supported.
2749 * New support for Matsushita MN10300 w/sim added
2750 (Work in progress). mn10300-elf.
2752 * REMOVED configurations and files
2754 VxWorks and the XDR protocol *-*-vxworks
2755 Motorola MCORE mcore-*-*
2756 National Semiconductor NS32000 ns32k-*-*
2758 * New "set print array-indexes" command
2760 After turning this setting "on", GDB prints the index of each element
2761 when displaying arrays. The default is "off" to preserve the previous
2764 * VAX floating point support
2766 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2768 * User-defined command support
2770 In addition to using $arg0..$arg9 for argument passing, it is now possible
2771 to use $argc to determine now many arguments have been passed. See the
2772 section on user-defined commands in the user manual for more information.
2774 *** Changes in GDB 6.3:
2776 * New command line option
2778 GDB now accepts -l followed by a number to set the timeout for remote
2781 * GDB works with GCC -feliminate-dwarf2-dups
2783 GDB now supports a more compact representation of DWARF-2 debug
2784 information using DW_FORM_ref_addr references. These are produced
2785 by GCC with the option -feliminate-dwarf2-dups and also by some
2786 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2787 to use -feliminate-dwarf2-dups.
2789 * Internationalization
2791 When supported by the host system, GDB will be built with
2792 internationalization (libintl). The task of marking up the sources is
2793 continued, we're looking forward to our first translation.
2797 Initial support for debugging programs compiled with the GNAT
2798 implementation of the Ada programming language has been integrated
2799 into GDB. In this release, support is limited to expression evaluation.
2801 * New native configurations
2803 GNU/Linux/m32r m32r-*-linux-gnu
2807 GDB's remote protocol now includes support for the 'p' packet. This
2808 packet is used to fetch individual registers from a remote inferior.
2810 * END-OF-LIFE registers[] compatibility module
2812 GDB's internal register infrastructure has been completely rewritten.
2813 The new infrastructure making possible the implementation of key new
2814 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2817 GDB 6.3 will be the last release to include the the registers[]
2818 compatibility module that allowed out-of-date configurations to
2819 continue to work. This change directly impacts the following
2829 powerpc bdm protocol
2831 Unless there is activity to revive these configurations, they will be
2832 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2834 * OBSOLETE configurations and files
2836 Configurations that have been declared obsolete in this release have
2837 been commented out. Unless there is activity to revive these
2838 configurations, the next release of GDB will have their sources
2839 permanently REMOVED.
2848 *** Changes in GDB 6.2.1:
2850 * MIPS `break main; run' gave an heuristic-fence-post warning
2852 When attempting to run even a simple program, a warning about
2853 heuristic-fence-post being hit would be reported. This problem has
2856 * MIPS IRIX 'long double' crashed GDB
2858 When examining a long double variable, GDB would get a segmentation
2859 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2860 IRIX long double values).
2864 A bug in the VAX stack code was causing problems with the "next"
2865 command. This problem has been fixed.
2867 *** Changes in GDB 6.2:
2869 * Fix for ``many threads''
2871 On GNU/Linux systems that use the NPTL threads library, a program
2872 rapidly creating and deleting threads would confuse GDB leading to the
2875 ptrace: No such process.
2876 thread_db_get_info: cannot get thread info: generic error
2878 This problem has been fixed.
2880 * "-async" and "-noasync" options removed.
2882 Support for the broken "-noasync" option has been removed (it caused
2885 * New ``start'' command.
2887 This command runs the program until the begining of the main procedure.
2889 * New BSD Kernel Data Access Library (libkvm) interface
2891 Using ``target kvm'' it is now possible to debug kernel core dumps and
2892 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2893 platforms. Currently supported (native-only) configurations are:
2895 FreeBSD/amd64 x86_64-*-freebsd*
2896 FreeBSD/i386 i?86-*-freebsd*
2897 NetBSD/i386 i?86-*-netbsd*
2898 NetBSD/m68k m68*-*-netbsd*
2899 NetBSD/sparc sparc-*-netbsd*
2900 OpenBSD/amd64 x86_64-*-openbsd*
2901 OpenBSD/i386 i?86-*-openbsd*
2902 OpenBSD/m68k m68*-openbsd*
2903 OpenBSD/sparc sparc-*-openbsd*
2905 * Signal trampoline code overhauled
2907 Many generic problems with GDB's signal handling code have been fixed.
2908 These include: backtraces through non-contiguous stacks; recognition
2909 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2910 call; backtrace through a signal trampoline; step into and out of
2911 signal handlers; and single-stepping in the signal trampoline.
2913 Please note that kernel bugs are a limiting factor here. These
2914 features have been shown to work on an s390 GNU/Linux system that
2915 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2917 * Cygwin support for DWARF 2 added.
2919 * New native configurations
2921 GNU/Linux/hppa hppa*-*-linux*
2922 OpenBSD/hppa hppa*-*-openbsd*
2923 OpenBSD/m68k m68*-*-openbsd*
2924 OpenBSD/m88k m88*-*-openbsd*
2925 OpenBSD/powerpc powerpc-*-openbsd*
2926 NetBSD/vax vax-*-netbsd*
2927 OpenBSD/vax vax-*-openbsd*
2929 * END-OF-LIFE frame compatibility module
2931 GDB's internal frame infrastructure has been completely rewritten.
2932 The new infrastructure making it possible to support key new features
2933 including DWARF 2 Call Frame Information. To aid in the task of
2934 migrating old configurations to this new infrastructure, a
2935 compatibility module, that allowed old configurations to continue to
2936 work, was also included.
2938 GDB 6.2 will be the last release to include this frame compatibility
2939 module. This change directly impacts the following configurations:
2949 Unless there is activity to revive these configurations, they will be
2950 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2952 * REMOVED configurations and files
2954 Sun 3, running SunOS 3 m68*-*-sunos3*
2955 Sun 3, running SunOS 4 m68*-*-sunos4*
2956 Sun 2, running SunOS 3 m68000-*-sunos3*
2957 Sun 2, running SunOS 4 m68000-*-sunos4*
2958 Motorola 680x0 running LynxOS m68*-*-lynxos*
2959 AT&T 3b1/Unix pc m68*-att-*
2960 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2961 decstation mips-dec-* mips-little-*
2962 riscos mips-*-riscos* mips-*-sysv*
2963 sonymips mips-sony-*
2964 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2966 *** Changes in GDB 6.1.1:
2968 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2970 The TUI (Text-mode User Interface) is now built as part of a default
2971 GDB configuration. It is enabled by either selecting the TUI with the
2972 command line option "-i=tui" or by running the separate "gdbtui"
2973 program. For more information on the TUI, see the manual "Debugging
2976 * Pending breakpoint support (also included in GDB 6.1)
2978 Support has been added to allow you to specify breakpoints in shared
2979 libraries that have not yet been loaded. If a breakpoint location
2980 cannot be found, and the "breakpoint pending" option is set to auto,
2981 GDB queries you if you wish to make the breakpoint pending on a future
2982 shared-library load. If and when GDB resolves the breakpoint symbol,
2983 the pending breakpoint is removed as one or more regular breakpoints
2986 Pending breakpoints are very useful for GCJ Java debugging.
2988 * Fixed ISO-C build problems
2990 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2991 non ISO-C code that stopped them being built using a more strict ISO-C
2992 compiler (e.g., IBM's C compiler).
2994 * Fixed build problem on IRIX 5
2996 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2997 wasn't able to compile compile on an IRIX 5 system.
2999 * Added execute permission to gdb/gdbserver/configure
3001 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
3002 permission. This bug would cause configure to fail on a number of
3003 systems (Solaris, IRIX). Ref: server/519.
3005 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3007 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3008 has been updated to use constant array sizes.
3010 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3012 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3013 its generated DWARF Call Frame Info. This encoding was causing GDB to
3014 panic, that panic has been fixed. Ref: gdb/1628.
3016 * Fixed a problem when examining parameters in shared library code.
3018 When examining parameters in optimized shared library code generated
3019 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3020 not available''. GDB now correctly displays the variable's value.
3022 *** Changes in GDB 6.1:
3024 * Removed --with-mmalloc
3026 Support for the mmalloc memory manager has been removed, as it
3027 conflicted with the internal gdb byte cache.
3029 * Changes in AMD64 configurations
3031 The AMD64 target now includes the %cs and %ss registers. As a result
3032 the AMD64 remote protocol has changed; this affects the floating-point
3033 and SSE registers. If you rely on those registers for your debugging,
3034 you should upgrade gdbserver on the remote side.
3036 * Revised SPARC target
3038 The SPARC target has been completely revised, incorporating the
3039 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3040 support for LynxOS and SunOS 4 has been dropped. Calling functions
3041 from within GDB on operating systems with a non-executable stack
3042 (Solaris, OpenBSD) now works.
3046 GDB has a new C++ demangler which does a better job on the mangled
3047 names generated by current versions of g++. It also runs faster, so
3048 with this and other changes gdb should now start faster on large C++
3051 * DWARF 2 Location Expressions
3053 GDB support for location expressions has been extended to support function
3054 arguments and frame bases. Older versions of GDB could crash when they
3057 * C++ nested types and namespaces
3059 GDB's support for nested types and namespaces in C++ has been
3060 improved, especially if you use the DWARF 2 debugging format. (This
3061 is the default for recent versions of GCC on most platforms.)
3062 Specifically, if you have a class "Inner" defined within a class or
3063 namespace "Outer", then GDB realizes that the class's name is
3064 "Outer::Inner", not simply "Inner". This should greatly reduce the
3065 frequency of complaints about not finding RTTI symbols. In addition,
3066 if you are stopped at inside of a function defined within a namespace,
3067 GDB modifies its name lookup accordingly.
3069 * New native configurations
3071 NetBSD/amd64 x86_64-*-netbsd*
3072 OpenBSD/amd64 x86_64-*-openbsd*
3073 OpenBSD/alpha alpha*-*-openbsd*
3074 OpenBSD/sparc sparc-*-openbsd*
3075 OpenBSD/sparc64 sparc64-*-openbsd*
3077 * New debugging protocols
3079 M32R with SDI protocol m32r-*-elf*
3081 * "set prompt-escape-char" command deleted.
3083 The command "set prompt-escape-char" has been deleted. This command,
3084 and its very obscure effet on GDB's prompt, was never documented,
3085 tested, nor mentioned in the NEWS file.
3087 * OBSOLETE configurations and files
3089 Configurations that have been declared obsolete in this release have
3090 been commented out. Unless there is activity to revive these
3091 configurations, the next release of GDB will have their sources
3092 permanently REMOVED.
3094 Sun 3, running SunOS 3 m68*-*-sunos3*
3095 Sun 3, running SunOS 4 m68*-*-sunos4*
3096 Sun 2, running SunOS 3 m68000-*-sunos3*
3097 Sun 2, running SunOS 4 m68000-*-sunos4*
3098 Motorola 680x0 running LynxOS m68*-*-lynxos*
3099 AT&T 3b1/Unix pc m68*-att-*
3100 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3101 decstation mips-dec-* mips-little-*
3102 riscos mips-*-riscos* mips-*-sysv*
3103 sonymips mips-sony-*
3104 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3106 * REMOVED configurations and files
3108 SGI Irix-4.x mips-sgi-irix4 or iris4
3109 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3110 Z8000 simulator z8k-zilog-none or z8ksim
3111 Matsushita MN10200 w/simulator mn10200-*-*
3112 H8/500 simulator h8500-hitachi-hms or h8500hms
3113 HP/PA running BSD hppa*-*-bsd*
3114 HP/PA running OSF/1 hppa*-*-osf*
3115 HP/PA Pro target hppa*-*-pro*
3116 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3117 386BSD i[3456]86-*-bsd*
3118 Sequent family i[3456]86-sequent-sysv4*
3119 i[3456]86-sequent-sysv*
3120 i[3456]86-sequent-bsd*
3121 SPARC running LynxOS sparc-*-lynxos*
3122 SPARC running SunOS 4 sparc-*-sunos4*
3123 Tsqware Sparclet sparclet-*-*
3124 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3126 *** Changes in GDB 6.0:
3130 Support for debugging the Objective-C programming language has been
3131 integrated into GDB.
3133 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3135 DWARF 2's Call Frame Information makes available compiler generated
3136 information that more exactly describes the program's run-time stack.
3137 By using this information, GDB is able to provide more robust stack
3140 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3141 have been updated to use a new backtrace mechanism which includes
3142 DWARF 2 CFI support.
3146 GDB's remote protocol has been extended to include support for hosted
3147 file I/O (where the remote target uses GDB's file system). See GDB's
3148 remote protocol documentation for details.
3150 * All targets using the new architecture framework.
3152 All of GDB's targets have been updated to use the new internal
3153 architecture framework. The way is now open for future GDB releases
3154 to include cross-architecture native debugging support (i386 on amd64,
3157 * GNU/Linux's Thread Local Storage (TLS)
3159 GDB now includes support for for the GNU/Linux implementation of
3160 per-thread variables.
3162 * GNU/Linux's Native POSIX Thread Library (NPTL)
3164 GDB's thread code has been updated to work with either the new
3165 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3167 * Separate debug info.
3169 GDB, in conjunction with BINUTILS, now supports a mechanism for
3170 automatically loading debug information from a separate file. Instead
3171 of shipping full debug and non-debug versions of system libraries,
3172 system integrators can now instead ship just the stripped libraries
3173 and optional debug files.
3175 * DWARF 2 Location Expressions
3177 DWARF 2 Location Expressions allow the compiler to more completely
3178 describe the location of variables (even in optimized code) to the
3181 GDB now includes preliminary support for location expressions (support
3182 for DW_OP_piece is still missing).
3186 A number of long standing bugs that caused GDB to die while starting a
3187 Java application have been fixed. GDB's Java support is now
3188 considered "useable".
3190 * GNU/Linux support for fork, vfork, and exec.
3192 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3193 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3196 * GDB supports logging output to a file
3198 There are two new commands, "set logging" and "show logging", which can be
3199 used to capture GDB's output to a file.
3201 * The meaning of "detach" has changed for gdbserver
3203 The "detach" command will now resume the application, as documented. To
3204 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3207 * d10v, m68hc11 `regs' command deprecated
3209 The `info registers' command has been updated so that it displays the
3210 registers using a format identical to the old `regs' command.
3214 A new command, "maint set profile on/off", has been added. This command can
3215 be used to enable or disable profiling while running GDB, to profile a
3216 session or a set of commands. In addition there is a new configure switch,
3217 "--enable-profiling", which will cause GDB to be compiled with profiling
3218 data, for more informative profiling results.
3220 * Default MI syntax changed to "mi2".
3222 The default MI (machine interface) syntax, enabled by the command line
3223 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3224 "mi1", can be enabled by specifying the option "-i=mi1".
3226 Support for the original "mi0" syntax (included in GDB 5.0) has been
3229 Fix for gdb/192: removed extraneous space when displaying frame level.
3230 Fix for gdb/672: update changelist is now output in mi list format.
3231 Fix for gdb/702: a -var-assign that updates the value now shows up
3232 in a subsequent -var-update.
3234 * New native configurations.
3236 FreeBSD/amd64 x86_64-*-freebsd*
3238 * Multi-arched targets.
3240 HP/PA HPUX11 hppa*-*-hpux*
3241 Renesas M32R/D w/simulator m32r-*-elf*
3243 * OBSOLETE configurations and files
3245 Configurations that have been declared obsolete in this release have
3246 been commented out. Unless there is activity to revive these
3247 configurations, the next release of GDB will have their sources
3248 permanently REMOVED.
3250 Z8000 simulator z8k-zilog-none or z8ksim
3251 Matsushita MN10200 w/simulator mn10200-*-*
3252 H8/500 simulator h8500-hitachi-hms or h8500hms
3253 HP/PA running BSD hppa*-*-bsd*
3254 HP/PA running OSF/1 hppa*-*-osf*
3255 HP/PA Pro target hppa*-*-pro*
3256 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3257 Sequent family i[3456]86-sequent-sysv4*
3258 i[3456]86-sequent-sysv*
3259 i[3456]86-sequent-bsd*
3260 Tsqware Sparclet sparclet-*-*
3261 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3263 * REMOVED configurations and files
3266 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3267 IBM AIX PS/2 i[3456]86-*-aix
3268 i386 running Mach 3.0 i[3456]86-*-mach3*
3269 i386 running Mach i[3456]86-*-mach*
3270 i386 running OSF/1 i[3456]86-*osf1mk*
3271 HP/Apollo 68k Family m68*-apollo*-sysv*,
3273 m68*-hp-bsd*, m68*-hp-hpux*
3274 Argonaut Risc Chip (ARC) arc-*-*
3275 Mitsubishi D30V d30v-*-*
3276 Fujitsu FR30 fr30-*-elf*
3277 OS/9000 i[34]86-*-os9k
3278 I960 with MON960 i960-*-coff
3280 * MIPS $fp behavior changed
3282 The convenience variable $fp, for the MIPS, now consistently returns
3283 the address of the current frame's base. Previously, depending on the
3284 context, $fp could refer to either $sp or the current frame's base
3285 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3286 The GNU Source-Level Debugger''.
3288 *** Changes in GDB 5.3:
3290 * GNU/Linux shared library multi-threaded performance improved.
3292 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3293 `/proc', in preference to `ptrace' for memory reads. This may result
3294 in an improvement in the start-up time of multi-threaded, shared
3295 library applications when run under GDB. One GDB user writes: ``loads
3296 shared libs like mad''.
3298 * ``gdbserver'' now supports multi-threaded applications on some targets
3300 Support for debugging multi-threaded applications which use
3301 the GNU/Linux LinuxThreads package has been added for
3302 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3303 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3305 * GDB now supports C/C++ preprocessor macros.
3307 GDB now expands preprocessor macro invocations in C/C++ expressions,
3308 and provides various commands for showing macro definitions and how
3311 The new command `macro expand EXPRESSION' expands any macro
3312 invocations in expression, and shows the result.
3314 The new command `show macro MACRO-NAME' shows the definition of the
3315 macro named MACRO-NAME, and where it was defined.
3317 Most compilers don't include information about macros in the debugging
3318 information by default. In GCC 3.1, for example, you need to compile
3319 your program with the options `-gdwarf-2 -g3'. If the macro
3320 information is present in the executable, GDB will read it.
3322 * Multi-arched targets.
3324 DEC Alpha (partial) alpha*-*-*
3325 DEC VAX (partial) vax-*-*
3327 National Semiconductor NS32000 (partial) ns32k-*-*
3328 Motorola 68000 (partial) m68k-*-*
3329 Motorola MCORE mcore-*-*
3333 Fujitsu FRV architecture added by Red Hat frv*-*-*
3336 * New native configurations
3338 Alpha NetBSD alpha*-*-netbsd*
3339 SH NetBSD sh*-*-netbsdelf*
3340 MIPS NetBSD mips*-*-netbsd*
3341 UltraSPARC NetBSD sparc64-*-netbsd*
3343 * OBSOLETE configurations and files
3345 Configurations that have been declared obsolete in this release have
3346 been commented out. Unless there is activity to revive these
3347 configurations, the next release of GDB will have their sources
3348 permanently REMOVED.
3350 Mitsubishi D30V d30v-*-*
3351 OS/9000 i[34]86-*-os9k
3352 IBM AIX PS/2 i[3456]86-*-aix
3353 Fujitsu FR30 fr30-*-elf*
3354 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3355 Argonaut Risc Chip (ARC) arc-*-*
3356 i386 running Mach 3.0 i[3456]86-*-mach3*
3357 i386 running Mach i[3456]86-*-mach*
3358 i386 running OSF/1 i[3456]86-*osf1mk*
3359 HP/Apollo 68k Family m68*-apollo*-sysv*,
3361 m68*-hp-bsd*, m68*-hp-hpux*
3362 I960 with MON960 i960-*-coff
3364 * OBSOLETE languages
3366 CHILL, a Pascal like language used by telecommunications companies.
3368 * REMOVED configurations and files
3370 AMD 29k family via UDI a29k-amd-udi, udi29k
3371 A29K VxWorks a29k-*-vxworks
3372 AMD 29000 embedded, using EBMON a29k-none-none
3373 AMD 29000 embedded with COFF a29k-none-coff
3374 AMD 29000 embedded with a.out a29k-none-aout
3376 testsuite/gdb.hp/gdb.threads-hp/ directory
3378 * New command "set max-user-call-depth <nnn>"
3380 This command allows the user to limit the call depth of user-defined
3381 commands. The default is 1024.
3383 * Changes in FreeBSD/i386 native debugging.
3385 Support for the "generate-core-file" has been added.
3387 * New commands "dump", "append", and "restore".
3389 These commands allow data to be copied from target memory
3390 to a bfd-format or binary file (dump and append), and back
3391 from a file into memory (restore).
3393 * Improved "next/step" support on multi-processor Alpha Tru64.
3395 The previous single-step mechanism could cause unpredictable problems,
3396 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3397 of a software single-step mechanism prevents this.
3399 *** Changes in GDB 5.2.1:
3407 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3408 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3409 Fix, by Joel Brobecker imported from mainline.
3411 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3412 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3413 Fix, by Fred Fish, imported from mainline.
3415 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3416 Surprisingly enough, it works now.
3417 By Michal Ludvig, imported from mainline.
3419 i386 hardware watchpoint support:
3420 avoid misses on second run for some targets.
3421 By Pierre Muller, imported from mainline.
3423 *** Changes in GDB 5.2:
3425 * New command "set trust-readonly-sections on[off]".
3427 This command is a hint that tells gdb that read-only sections
3428 really are read-only (ie. that their contents will not change).
3429 In this mode, gdb will go to the object file rather than the
3430 target to read memory from read-only sections (such as ".text").
3431 This can be a significant performance improvement on some
3432 (notably embedded) targets.
3434 * New command "generate-core-file" (or "gcore").
3436 This new gdb command allows the user to drop a core file of the child
3437 process state at any time. So far it's been implemented only for
3438 GNU/Linux and Solaris, but should be relatively easily ported to other
3439 hosts. Argument is core file name (defaults to core.<pid>).
3441 * New command line option
3443 GDB now accepts --pid or -p followed by a process id.
3445 * Change in command line behavior -- corefiles vs. process ids.
3447 There is a subtle behavior in the way in which GDB handles
3448 command line arguments. The first non-flag argument is always
3449 a program to debug, but the second non-flag argument may either
3450 be a corefile or a process id. Previously, GDB would attempt to
3451 open the second argument as a corefile, and if that failed, would
3452 issue a superfluous error message and then attempt to attach it as
3453 a process. Now, if the second argument begins with a non-digit,
3454 it will be treated as a corefile. If it begins with a digit,
3455 GDB will attempt to attach it as a process, and if no such process
3456 is found, will then attempt to open it as a corefile.
3458 * Changes in ARM configurations.
3460 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3461 configuration is fully multi-arch.
3463 * New native configurations
3465 ARM NetBSD arm*-*-netbsd*
3466 x86 OpenBSD i[3456]86-*-openbsd*
3467 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3468 Sparc64 running FreeBSD sparc64-*-freebsd*
3472 Sanyo XStormy16 xstormy16-elf
3474 * OBSOLETE configurations and files
3476 Configurations that have been declared obsolete in this release have
3477 been commented out. Unless there is activity to revive these
3478 configurations, the next release of GDB will have their sources
3479 permanently REMOVED.
3481 AMD 29k family via UDI a29k-amd-udi, udi29k
3482 A29K VxWorks a29k-*-vxworks
3483 AMD 29000 embedded, using EBMON a29k-none-none
3484 AMD 29000 embedded with COFF a29k-none-coff
3485 AMD 29000 embedded with a.out a29k-none-aout
3487 testsuite/gdb.hp/gdb.threads-hp/ directory
3489 * REMOVED configurations and files
3491 TI TMS320C80 tic80-*-*
3493 PowerPC Solaris powerpcle-*-solaris*
3494 PowerPC Windows NT powerpcle-*-cygwin32
3495 PowerPC Netware powerpc-*-netware*
3496 Harris/CXUX m88k m88*-harris-cxux*
3497 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3498 ns32k-utek-sysv* ns32k-utek-*
3499 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3500 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3501 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3502 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3503 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3505 * Changes to command line processing
3507 The new `--args' feature can be used to specify command-line arguments
3508 for the inferior from gdb's command line.
3510 * Changes to key bindings
3512 There is a new `operate-and-get-next' function bound to `C-o'.
3514 *** Changes in GDB 5.1.1
3516 Fix compile problem on DJGPP.
3518 Fix a problem with floating-point registers on the i386 being
3521 Fix to stop GDB crashing on .debug_str debug info.
3523 Numerous documentation fixes.
3525 Numerous testsuite fixes.
3527 *** Changes in GDB 5.1:
3529 * New native configurations
3531 Alpha FreeBSD alpha*-*-freebsd*
3532 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3533 MIPS GNU/Linux mips*-*-linux*
3534 MIPS SGI Irix 6.x mips*-sgi-irix6*
3535 ia64 AIX ia64-*-aix*
3536 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3540 Motorola 68HC11 and 68HC12 m68hc11-elf
3542 UltraSparc running GNU/Linux sparc64-*-linux*
3544 * OBSOLETE configurations and files
3546 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3547 Harris/CXUX m88k m88*-harris-cxux*
3548 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3549 ns32k-utek-sysv* ns32k-utek-*
3550 TI TMS320C80 tic80-*-*
3552 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3553 PowerPC Solaris powerpcle-*-solaris*
3554 PowerPC Windows NT powerpcle-*-cygwin32
3555 PowerPC Netware powerpc-*-netware*
3556 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3557 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3558 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3559 Apple Macintosh (MPW) host N/A
3561 stuff.c (Program to stuff files into a specially prepared space in kdb)
3562 kdb-start.c (Main loop for the standalone kernel debugger)
3564 Configurations that have been declared obsolete in this release have
3565 been commented out. Unless there is activity to revive these
3566 configurations, the next release of GDB will have their sources
3567 permanently REMOVED.
3569 * REMOVED configurations and files
3571 Altos 3068 m68*-altos-*
3572 Convex c1-*-*, c2-*-*
3574 ARM RISCix arm-*-* (as host)
3578 * GDB has been converted to ISO C.
3580 GDB's source code has been converted to ISO C. In particular, the
3581 sources are fully protoized, and rely on standard headers being
3586 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3588 * The MI enabled by default.
3590 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3591 revised and enabled by default. Packages which use GDB as a debugging
3592 engine behind a UI or another front end are encouraged to switch to
3593 using the GDB/MI interface, instead of the old annotations interface
3594 which is now deprecated.
3596 * Support for debugging Pascal programs.
3598 GDB now includes support for debugging Pascal programs. The following
3599 main features are supported:
3601 - Pascal-specific data types such as sets;
3603 - automatic recognition of Pascal sources based on file-name
3606 - Pascal-style display of data types, variables, and functions;
3608 - a Pascal expression parser.
3610 However, some important features are not yet supported.
3612 - Pascal string operations are not supported at all;
3614 - there are some problems with boolean types;
3616 - Pascal type hexadecimal constants are not supported
3617 because they conflict with the internal variables format;
3619 - support for Pascal objects and classes is not full yet;
3621 - unlike Pascal, GDB is case-sensitive for symbol names.
3623 * Changes in completion.
3625 Commands such as `shell', `run' and `set args', which pass arguments
3626 to inferior programs, now complete on file names, similar to what
3627 users expect at the shell prompt.
3629 Commands which accept locations, such as `disassemble', `print',
3630 `breakpoint', `until', etc. now complete on filenames as well as
3631 program symbols. Thus, if you type "break foob TAB", and the source
3632 files linked into the programs include `foobar.c', that file name will
3633 be one of the candidates for completion. However, file names are not
3634 considered for completion after you typed a colon that delimits a file
3635 name from a name of a function in that file, as in "break foo.c:bar".
3637 `set demangle-style' completes on available demangling styles.
3639 * New platform-independent commands:
3641 It is now possible to define a post-hook for a command as well as a
3642 hook that runs before the command. For more details, see the
3643 documentation of `hookpost' in the GDB manual.
3645 * Changes in GNU/Linux native debugging.
3647 Support for debugging multi-threaded programs has been completely
3648 revised for all platforms except m68k and sparc. You can now debug as
3649 many threads as your system allows you to have.
3651 Attach/detach is supported for multi-threaded programs.
3653 Support for SSE registers was added for x86. This doesn't work for
3654 multi-threaded programs though.
3656 * Changes in MIPS configurations.
3658 Multi-arch support is enabled for all MIPS configurations.
3660 GDB can now be built as native debugger on SGI Irix 6.x systems for
3661 debugging n32 executables. (Debugging 64-bit executables is not yet
3664 * Unified support for hardware watchpoints in all x86 configurations.
3666 Most (if not all) native x86 configurations support hardware-assisted
3667 breakpoints and watchpoints in a unified manner. This support
3668 implements debug register sharing between watchpoints, which allows to
3669 put a virtually infinite number of watchpoints on the same address,
3670 and also supports watching regions up to 16 bytes with several debug
3673 The new maintenance command `maintenance show-debug-regs' toggles
3674 debugging print-outs in functions that insert, remove, and test
3675 watchpoints and hardware breakpoints.
3677 * Changes in the DJGPP native configuration.
3679 New command ``info dos sysinfo'' displays assorted information about
3680 the CPU, OS, memory, and DPMI server.
3682 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3683 display information about segment descriptors stored in GDT, LDT, and
3686 New commands ``info dos pde'' and ``info dos pte'' display entries
3687 from Page Directory and Page Tables (for now works with CWSDPMI only).
3688 New command ``info dos address-pte'' displays the Page Table entry for
3689 a given linear address.
3691 GDB can now pass command lines longer than 126 characters to the
3692 program being debugged (requires an update to the libdbg.a library
3693 which is part of the DJGPP development kit).
3695 DWARF2 debug info is now supported.
3697 It is now possible to `step' and `next' through calls to `longjmp'.
3699 * Changes in documentation.
3701 All GDB documentation was converted to GFDL, the GNU Free
3702 Documentation License.
3704 Tracepoints-related commands are now fully documented in the GDB
3707 TUI, the Text-mode User Interface, is now documented in the manual.
3709 Tracepoints-related commands are now fully documented in the GDB
3712 The "GDB Internals" manual now has an index. It also includes
3713 documentation of `ui_out' functions, GDB coding standards, x86
3714 hardware watchpoints, and memory region attributes.
3716 * GDB's version number moved to ``version.in''
3718 The Makefile variable VERSION has been replaced by the file
3719 ``version.in''. People creating GDB distributions should update the
3720 contents of this file.
3724 GUD support is now a standard part of the EMACS distribution.
3726 *** Changes in GDB 5.0:
3728 * Improved support for debugging FP programs on x86 targets
3730 Unified and much-improved support for debugging floating-point
3731 programs on all x86 targets. In particular, ``info float'' now
3732 displays the FP registers in the same format on all x86 targets, with
3733 greater level of detail.
3735 * Improvements and bugfixes in hardware-assisted watchpoints
3737 It is now possible to watch array elements, struct members, and
3738 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3739 on x86 targets no longer erroneously trigger when the address is
3742 * Improvements in the native DJGPP version of GDB
3744 The distribution now includes all the scripts and auxiliary files
3745 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3746 machines ``out of the box''.
3748 The DJGPP version can now debug programs that use signals. It is
3749 possible to catch signals that happened in the debuggee, deliver
3750 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3751 would kill the program being debugged.) Programs that hook hardware
3752 interrupts (keyboard, timer, etc.) can also be debugged.
3754 It is now possible to debug DJGPP programs that redirect their
3755 standard handles or switch them to raw (as opposed to cooked) mode, or
3756 even close them. The command ``run < foo > bar'' works as expected,
3757 and ``info terminal'' reports useful information about the debuggee's
3758 terminal, including raw/cooked mode, redirection, etc.
3760 The DJGPP version now uses termios functions for console I/O, which
3761 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3764 DOS-style file names with drive letters are now fully supported by
3767 It is now possible to debug DJGPP programs that switch their working
3768 directory. It is also possible to rerun the debuggee any number of
3769 times without restarting GDB; thus, you can use the same setup,
3770 breakpoints, etc. for many debugging sessions.
3772 * New native configurations
3774 ARM GNU/Linux arm*-*-linux*
3775 PowerPC GNU/Linux powerpc-*-linux*
3779 Motorola MCore mcore-*-*
3780 x86 VxWorks i[3456]86-*-vxworks*
3781 PowerPC VxWorks powerpc-*-vxworks*
3782 TI TMS320C80 tic80-*-*
3784 * OBSOLETE configurations
3786 Altos 3068 m68*-altos-*
3787 Convex c1-*-*, c2-*-*
3789 ARM RISCix arm-*-* (as host)
3792 Configurations that have been declared obsolete will be commented out,
3793 but the code will be left in place. If there is no activity to revive
3794 these configurations before the next release of GDB, the sources will
3795 be permanently REMOVED.
3797 * Gould support removed
3799 Support for the Gould PowerNode and NP1 has been removed.
3801 * New features for SVR4
3803 On SVR4 native platforms (such as Solaris), if you attach to a process
3804 without first loading a symbol file, GDB will now attempt to locate and
3805 load symbols from the running process's executable file.
3807 * Many C++ enhancements
3809 C++ support has been greatly improved. Overload resolution now works properly
3810 in almost all cases. RTTI support is on the way.
3812 * Remote targets can connect to a sub-program
3814 A popen(3) style serial-device has been added. This device starts a
3815 sub-process (such as a stand-alone simulator) and then communicates
3816 with that. The sub-program to run is specified using the syntax
3817 ``|<program> <args>'' vis:
3819 (gdb) set remotedebug 1
3820 (gdb) target extended-remote |mn10300-elf-sim program-args
3822 * MIPS 64 remote protocol
3824 A long standing bug in the mips64 remote protocol where by GDB
3825 expected certain 32 bit registers (ex SR) to be transfered as 32
3826 instead of 64 bits has been fixed.
3828 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3829 added to provide backward compatibility with older versions of GDB.
3831 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3833 The command ``set remotebinarydownload'' command has been replaced by
3834 ``set remote X-packet''. Other commands in ``set remote'' family
3835 include ``set remote P-packet''.
3837 * Breakpoint commands accept ranges.
3839 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3840 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3841 ``tracepoint passcount'' also accepts a range of tracepoints.
3843 * ``apropos'' command added.
3845 The ``apropos'' command searches through command names and
3846 documentation strings, printing out matches, making it much easier to
3847 try to find a command that does what you are looking for.
3851 A new machine oriented interface (MI) has been added to GDB. This
3852 interface is designed for debug environments running GDB as a separate
3853 process. This is part of the long term libGDB project. See the
3854 "GDB/MI" chapter of the GDB manual for further information. It can be
3855 enabled by configuring with:
3857 .../configure --enable-gdbmi
3859 *** Changes in GDB-4.18:
3861 * New native configurations
3863 HP-UX 10.20 hppa*-*-hpux10.20
3864 HP-UX 11.x hppa*-*-hpux11.0*
3865 M68K GNU/Linux m68*-*-linux*
3869 Fujitsu FR30 fr30-*-elf*
3870 Intel StrongARM strongarm-*-*
3871 Mitsubishi D30V d30v-*-*
3873 * OBSOLETE configurations
3875 Gould PowerNode, NP1 np1-*-*, pn-*-*
3877 Configurations that have been declared obsolete will be commented out,
3878 but the code will be left in place. If there is no activity to revive
3879 these configurations before the next release of GDB, the sources will
3880 be permanently REMOVED.
3884 As a compatibility experiment, GDB's source files buildsym.h and
3885 buildsym.c have been converted to pure standard C, no longer
3886 containing any K&R compatibility code. We believe that all systems in
3887 use today either come with a standard C compiler, or have a GCC port
3888 available. If this is not true, please report the affected
3889 configuration to bug-gdb@gnu.org immediately. See the README file for
3890 information about getting a standard C compiler if you don't have one
3895 GDB now uses readline 2.2.
3897 * set extension-language
3899 You can now control the mapping between filename extensions and source
3900 languages by using the `set extension-language' command. For instance,
3901 you can ask GDB to treat .c files as C++ by saying
3902 set extension-language .c c++
3903 The command `info extensions' lists all of the recognized extensions
3904 and their associated languages.
3906 * Setting processor type for PowerPC and RS/6000
3908 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3909 you can use the `set processor' command to specify what variant of the
3910 PowerPC family you are debugging. The command
3914 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3915 following PowerPC and RS6000 variants:
3917 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3918 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3920 403GC IBM PowerPC 403GC
3921 505 Motorola PowerPC 505
3922 860 Motorola PowerPC 860 or 850
3923 601 Motorola PowerPC 601
3924 602 Motorola PowerPC 602
3925 603 Motorola/IBM PowerPC 603 or 603e
3926 604 Motorola PowerPC 604 or 604e
3927 750 Motorola/IBM PowerPC 750 or 750
3929 At the moment, this command just tells GDB what to name the
3930 special-purpose processor registers. Since almost all the affected
3931 registers are inaccessible to user-level programs, this command is
3932 only useful for remote debugging in its present form.
3936 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3937 more extensive support for HP-UX. Added features include shared
3938 library support, kernel threads and hardware watchpoints for 11.00,
3939 support for HP's ANSI C and C++ compilers, and a compatibility mode
3940 for xdb and dbx commands.
3944 HP's donation includes the new concept of catchpoints, which is a
3945 generalization of the old catch command. On HP-UX, it is now possible
3946 to catch exec, fork, and vfork, as well as library loading.
3948 This means that the existing catch command has changed; its first
3949 argument now specifies the type of catch to be set up. See the
3950 output of "help catch" for a list of catchpoint types.
3952 * Debugging across forks
3954 On HP-UX, you can choose which process to debug when a fork() happens
3959 HP has donated a curses-based terminal user interface (TUI). To get
3960 it, build with --enable-tui. Although this can be enabled for any
3961 configuration, at present it only works for native HP debugging.
3963 * GDB remote protocol additions
3965 A new protocol packet 'X' that writes binary data is now available.
3966 Default behavior is to try 'X', then drop back to 'M' if the stub
3967 fails to respond. The settable variable `remotebinarydownload'
3968 allows explicit control over the use of 'X'.
3970 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3971 full 64-bit address. The command
3973 set remoteaddresssize 32
3975 can be used to revert to the old behaviour. For existing remote stubs
3976 the change should not be noticed, as the additional address information
3979 In order to assist in debugging stubs, you may use the maintenance
3980 command `packet' to send any text string to the stub. For instance,
3982 maint packet heythere
3984 sends the packet "$heythere#<checksum>". Note that it is very easy to
3985 disrupt a debugging session by sending the wrong packet at the wrong
3988 The compare-sections command allows you to compare section data on the
3989 target to what is in the executable file without uploading or
3990 downloading, by comparing CRC checksums.
3992 * Tracing can collect general expressions
3994 You may now collect general expressions at tracepoints. This requires
3995 further additions to the target-side stub; see tracepoint.c and
3996 doc/agentexpr.texi for further details.
3998 * mask-address variable for Mips
4000 For Mips targets, you may control the zeroing of the upper 32 bits of
4001 a 64-bit address by entering `set mask-address on'. This is mainly
4002 of interest to users of embedded R4xxx and R5xxx processors.
4004 * Higher serial baud rates
4006 GDB's serial code now allows you to specify baud rates 57600, 115200,
4007 230400, and 460800 baud. (Note that your host system may not be able
4008 to achieve all of these rates.)
4012 The i960 configuration now includes an initial implementation of a
4013 builtin simulator, contributed by Jim Wilson.
4016 *** Changes in GDB-4.17:
4018 * New native configurations
4020 Alpha GNU/Linux alpha*-*-linux*
4021 Unixware 2.x i[3456]86-unixware2*
4022 Irix 6.x mips*-sgi-irix6*
4023 PowerPC GNU/Linux powerpc-*-linux*
4024 PowerPC Solaris powerpcle-*-solaris*
4025 Sparc GNU/Linux sparc-*-linux*
4026 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4030 Argonaut Risc Chip (ARC) arc-*-*
4031 Hitachi H8/300S h8300*-*-*
4032 Matsushita MN10200 w/simulator mn10200-*-*
4033 Matsushita MN10300 w/simulator mn10300-*-*
4034 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4035 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4036 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4037 Mitsubishi D10V w/simulator d10v-*-*
4038 Mitsubishi M32R/D w/simulator m32r-*-elf*
4039 Tsqware Sparclet sparclet-*-*
4040 NEC V850 w/simulator v850-*-*
4042 * New debugging protocols
4044 ARM with RDI protocol arm*-*-*
4045 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4046 DDB and LSI variants of PMON protocol mips*-*-*
4047 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4048 PowerPC with SDS protocol powerpc{,le}-*-eabi
4049 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4053 All configurations can now understand and use the DWARF 2 debugging
4054 format. The choice is automatic, if the symbol file contains DWARF 2
4059 GDB now includes basic Java language support. This support is
4060 only useful with Java compilers that produce native machine code.
4062 * solib-absolute-prefix and solib-search-path
4064 For SunOS and SVR4 shared libraries, you may now set the prefix for
4065 loading absolute shared library symbol files, and the search path for
4066 locating non-absolute shared library symbol files.
4068 * Live range splitting
4070 GDB can now effectively debug code for which GCC has performed live
4071 range splitting as part of its optimization. See gdb/doc/LRS for
4072 more details on the expected format of the stabs information.
4076 GDB's support for the GNU Hurd, including thread debugging, has been
4077 updated to work with current versions of the Hurd.
4081 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4082 instruction set. ARM GDB automatically detects when Thumb
4083 instructions are in use, and adjusts disassembly and backtracing
4088 GDB's MIPS target configurations now handle the MIP16 16-bit
4093 GDB now includes support for overlays; if an executable has been
4094 linked such that multiple sections are based at the same address, GDB
4095 will decide which section to use for symbolic info. You can choose to
4096 control the decision manually, using overlay commands, or implement
4097 additional target-side support and use "overlay load-target" to bring
4098 in the overlay mapping. Do "help overlay" for more detail.
4102 The command "info symbol <address>" displays information about
4103 the symbol at the specified address.
4107 The standard remote protocol now includes an extension that allows
4108 asynchronous collection and display of trace data. This requires
4109 extensive support in the target-side debugging stub. Tracing mode
4110 includes a new interaction mode in GDB and new commands: see the
4111 file tracepoint.c for more details.
4115 Configurations for embedded MIPS now include a simulator contributed
4116 by Cygnus Solutions. The simulator supports the instruction sets
4117 of most MIPS variants.
4121 Sparc configurations may now include the ERC32 simulator contributed
4122 by the European Space Agency. The simulator is not built into
4123 Sparc targets by default; configure with --enable-sim to include it.
4127 For target configurations that may include multiple variants of a
4128 basic architecture (such as MIPS and SH), you may now set the
4129 architecture explicitly. "set arch" sets, "info arch" lists
4130 the possible architectures.
4132 *** Changes in GDB-4.16:
4134 * New native configurations
4136 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4137 M68K NetBSD m68k-*-netbsd*
4138 PowerPC AIX 4.x powerpc-*-aix*
4139 PowerPC MacOS powerpc-*-macos*
4140 PowerPC Windows NT powerpcle-*-cygwin32
4141 RS/6000 AIX 4.x rs6000-*-aix4*
4145 ARM with RDP protocol arm-*-*
4146 I960 with MON960 i960-*-coff
4147 MIPS VxWorks mips*-*-vxworks*
4148 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4149 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4151 Matra Sparclet sparclet-*-*
4155 The powerpc-eabi configuration now includes the PSIM simulator,
4156 contributed by Andrew Cagney, with assistance from Mike Meissner.
4157 PSIM is a very elaborate model of the PowerPC, including not only
4158 basic instruction set execution, but also details of execution unit
4159 performance and I/O hardware. See sim/ppc/README for more details.
4163 GDB now works with Solaris 2.5.
4165 * Windows 95/NT native
4167 GDB will now work as a native debugger on Windows 95 and Windows NT.
4168 To build it from source, you must use the "gnu-win32" environment,
4169 which uses a DLL to emulate enough of Unix to run the GNU tools.
4170 Further information, binaries, and sources are available at
4171 ftp.cygnus.com, under pub/gnu-win32.
4173 * dont-repeat command
4175 If a user-defined command includes the command `dont-repeat', then the
4176 command will not be repeated if the user just types return. This is
4177 useful if the command is time-consuming to run, so that accidental
4178 extra keystrokes don't run the same command many times.
4180 * Send break instead of ^C
4182 The standard remote protocol now includes an option to send a break
4183 rather than a ^C to the target in order to interrupt it. By default,
4184 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4186 * Remote protocol timeout
4188 The standard remote protocol includes a new variable `remotetimeout'
4189 that allows you to set the number of seconds before GDB gives up trying
4190 to read from the target. The default value is 2.
4192 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4194 By default GDB will automatically keep track of objects as they are
4195 loaded and unloaded by the dynamic linker. By using the command `set
4196 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4197 when shared library events occur, thus allowing you to set breakpoints
4198 in shared libraries which are explicitly loaded by the inferior.
4200 Note this feature does not work on hpux8. On hpux9 you must link
4201 /usr/lib/end.o into your program. This feature should work
4202 automatically on hpux10.
4204 * Irix 5.x hardware watchpoint support
4206 Irix 5 configurations now support the use of hardware watchpoints.
4208 * Mips protocol "SYN garbage limit"
4210 When debugging a Mips target using the `target mips' protocol, you
4211 may set the number of characters that GDB will ignore by setting
4212 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4213 every character. The default value is 1050.
4215 * Recording and replaying remote debug sessions
4217 If you set `remotelogfile' to the name of a file, gdb will write to it
4218 a recording of a remote debug session. This recording may then be
4219 replayed back to gdb using "gdbreplay". See gdbserver/README for
4220 details. This is useful when you have a problem with GDB while doing
4221 remote debugging; you can make a recording of the session and send it
4222 to someone else, who can then recreate the problem.
4224 * Speedups for remote debugging
4226 GDB includes speedups for downloading and stepping MIPS systems using
4227 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4228 and more efficient S-record downloading.
4230 * Memory use reductions and statistics collection
4232 GDB now uses less memory and reports statistics about memory usage.
4233 Try the `maint print statistics' command, for example.
4235 *** Changes in GDB-4.15:
4237 * Psymtabs for XCOFF
4239 The symbol reader for AIX GDB now uses partial symbol tables. This
4240 can greatly improve startup time, especially for large executables.
4242 * Remote targets use caching
4244 Remote targets now use a data cache to speed up communication with the
4245 remote side. The data cache could lead to incorrect results because
4246 it doesn't know about volatile variables, thus making it impossible to
4247 debug targets which use memory mapped I/O devices. `set remotecache
4248 off' turns the the data cache off.
4250 * Remote targets may have threads
4252 The standard remote protocol now includes support for multiple threads
4253 in the target system, using new protocol commands 'H' and 'T'. See
4254 gdb/remote.c for details.
4258 If GDB is configured with `--enable-netrom', then it will include
4259 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4260 acts as though it is a bank of ROM on the target board, but you can
4261 write into it over the network. GDB's support consists only of
4262 support for fast loading into the emulated ROM; to debug, you must use
4263 another protocol, such as standard remote protocol. The usual
4264 sequence is something like
4266 target nrom <netrom-hostname>
4268 target remote <netrom-hostname>:1235
4272 GDB now includes support for the Apple Macintosh, as a host only. It
4273 may be run as either an MPW tool or as a standalone application, and
4274 it can debug through the serial port. All the usual GDB commands are
4275 available, but to the target command, you must supply "serial" as the
4276 device type instead of "/dev/ttyXX". See mpw-README in the main
4277 directory for more information on how to build. The MPW configuration
4278 scripts */mpw-config.in support only a few targets, and only the
4279 mips-idt-ecoff target has been tested.
4283 GDB configuration now uses autoconf. This is not user-visible,
4284 but does simplify configuration and building.
4288 GDB now supports hpux10.
4290 *** Changes in GDB-4.14:
4292 * New native configurations
4294 x86 FreeBSD i[345]86-*-freebsd
4295 x86 NetBSD i[345]86-*-netbsd
4296 NS32k NetBSD ns32k-*-netbsd
4297 Sparc NetBSD sparc-*-netbsd
4301 A29K VxWorks a29k-*-vxworks
4302 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4303 CPU32 EST-300 emulator m68*-*-est*
4304 PowerPC ELF powerpc-*-elf
4307 * Alpha OSF/1 support for procfs
4309 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4310 possible to attach to running processes. As the mounting of the /proc
4311 filesystem is optional on the Alpha, GDB automatically determines
4312 the availability of /proc during startup. This can lead to problems
4313 if /proc is unmounted after GDB has been started.
4315 * Arguments to user-defined commands
4317 User commands may accept up to 10 arguments separated by whitespace.
4318 Arguments are accessed within the user command via $arg0..$arg9. A
4321 print $arg0 + $arg1 + $arg2
4323 To execute the command use:
4326 Defines the command "adder" which prints the sum of its three arguments.
4327 Note the arguments are text substitutions, so they may reference variables,
4328 use complex expressions, or even perform inferior function calls.
4330 * New `if' and `while' commands
4332 This makes it possible to write more sophisticated user-defined
4333 commands. Both commands take a single argument, which is the
4334 expression to evaluate, and must be followed by the commands to
4335 execute, one per line, if the expression is nonzero, the list being
4336 terminated by the word `end'. The `if' command list may include an
4337 `else' word, which causes the following commands to be executed only
4338 if the expression is zero.
4340 * Fortran source language mode
4342 GDB now includes partial support for Fortran 77. It will recognize
4343 Fortran programs and can evaluate a subset of Fortran expressions, but
4344 variables and functions may not be handled correctly. GDB will work
4345 with G77, but does not yet know much about symbols emitted by other
4348 * Better HPUX support
4350 Most debugging facilities now work on dynamic executables for HPPAs
4351 running hpux9 or later. You can attach to running dynamically linked
4352 processes, but by default the dynamic libraries will be read-only, so
4353 for instance you won't be able to put breakpoints in them. To change
4354 that behavior do the following before running the program:
4360 This will cause the libraries to be mapped private and read-write.
4361 To revert to the normal behavior, do this:
4367 You cannot set breakpoints or examine data in the library until after
4368 the library is loaded if the function/data symbols do not have
4371 GDB can now also read debug symbols produced by the HP C compiler on
4372 HPPAs (sorry, no C++, Fortran or 68k support).
4374 * Target byte order now dynamically selectable
4376 You can choose which byte order to use with a target system, via the
4377 commands "set endian big" and "set endian little", and you can see the
4378 current setting by using "show endian". You can also give the command
4379 "set endian auto", in which case GDB will use the byte order
4380 associated with the executable. Currently, only embedded MIPS
4381 configurations support dynamic selection of target byte order.
4383 * New DOS host serial code
4385 This version uses DPMI interrupts to handle buffered I/O, so you
4386 no longer need to run asynctsr when debugging boards connected to
4389 *** Changes in GDB-4.13:
4391 * New "complete" command
4393 This lists all the possible completions for the rest of the line, if it
4394 were to be given as a command itself. This is intended for use by emacs.
4396 * Trailing space optional in prompt
4398 "set prompt" no longer adds a space for you after the prompt you set. This
4399 allows you to set a prompt which ends in a space or one that does not.
4401 * Breakpoint hit counts
4403 "info break" now displays a count of the number of times the breakpoint
4404 has been hit. This is especially useful in conjunction with "ignore"; you
4405 can ignore a large number of breakpoint hits, look at the breakpoint info
4406 to see how many times the breakpoint was hit, then run again, ignoring one
4407 less than that number, and this will get you quickly to the last hit of
4410 * Ability to stop printing at NULL character
4412 "set print null-stop" will cause GDB to stop printing the characters of
4413 an array when the first NULL is encountered. This is useful when large
4414 arrays actually contain only short strings.
4416 * Shared library breakpoints
4418 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4419 breakpoints in shared libraries before the executable is run.
4421 * Hardware watchpoints
4423 There is a new hardware breakpoint for the watch command for sparclite
4424 targets. See gdb/sparclite/hw_breakpoint.note.
4426 Hardware watchpoints are also now supported under GNU/Linux.
4430 Annotations have been added. These are for use with graphical interfaces,
4431 and are still experimental. Currently only gdba.el uses these.
4433 * Improved Irix 5 support
4435 GDB now works properly with Irix 5.2.
4437 * Improved HPPA support
4439 GDB now works properly with the latest GCC and GAS.
4441 * New native configurations
4443 Sequent PTX4 i[34]86-sequent-ptx4
4444 HPPA running OSF/1 hppa*-*-osf*
4445 Atari TT running SVR4 m68*-*-sysv4*
4446 RS/6000 LynxOS rs6000-*-lynxos*
4450 OS/9000 i[34]86-*-os9k
4451 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4454 * Hitachi SH7000 and E7000-PC ICE support
4456 There is now support for communicating with the Hitachi E7000-PC ICE.
4457 This is available automatically when GDB is configured for the SH.
4461 As usual, a variety of small fixes and improvements, both generic
4462 and configuration-specific. See the ChangeLog for more detail.
4464 *** Changes in GDB-4.12:
4466 * Irix 5 is now supported
4470 GDB-4.12 on the HPPA has a number of changes which make it unable
4471 to debug the output from the currently released versions of GCC and
4472 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4473 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4474 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4477 *** Changes in GDB-4.11:
4479 * User visible changes:
4483 The "set remotedebug" option is now consistent between the mips remote
4484 target, remote targets using the gdb-specific protocol, UDI (AMD's
4485 debug protocol for the 29k) and the 88k bug monitor. It is now an
4486 integer specifying a debug level (normally 0 or 1, but 2 means more
4487 debugging info for the mips target).
4489 * DEC Alpha native support
4491 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4492 debug info, but GDB works fairly well with the DEC compiler and should
4493 work with a future GCC release. See the README file for a few
4494 Alpha-specific notes.
4496 * Preliminary thread implementation
4498 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4500 * LynxOS native and target support for 386
4502 This release has been hosted on LynxOS 2.2, and also can be configured
4503 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4506 * Improvements in C++ mangling/demangling.
4508 This release has much better g++ debugging, specifically in name
4509 mangling/demangling, virtual function calls, print virtual table,
4510 call methods, ...etc.
4512 *** Changes in GDB-4.10:
4514 * User visible changes:
4516 Remote debugging using the GDB-specific (`target remote') protocol now
4517 supports the `load' command. This is only useful if you have some
4518 other way of getting the stub to the target system, and you can put it
4519 somewhere in memory where it won't get clobbered by the download.
4521 Filename completion now works.
4523 When run under emacs mode, the "info line" command now causes the
4524 arrow to point to the line specified. Also, "info line" prints
4525 addresses in symbolic form (as well as hex).
4527 All vxworks based targets now support a user settable option, called
4528 vxworks-timeout. This option represents the number of seconds gdb
4529 should wait for responses to rpc's. You might want to use this if
4530 your vxworks target is, perhaps, a slow software simulator or happens
4531 to be on the far side of a thin network line.
4535 This release contains support for using a DEC alpha as a GDB host for
4536 cross debugging. Native alpha debugging is not supported yet.
4539 *** Changes in GDB-4.9:
4543 This is the first GDB release which is accompanied by a matching testsuite.
4544 The testsuite requires installation of dejagnu, which should be available
4545 via ftp from most sites that carry GNU software.
4549 'Cfront' style demangling has had its name changed to 'ARM' style, to
4550 emphasize that it was written from the specifications in the C++ Annotated
4551 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4552 disclaimers, it still generated too much confusion with users attempting to
4553 use gdb with AT&T cfront.
4557 GDB now uses a standard remote interface to a simulator library.
4558 So far, the library contains simulators for the Zilog Z8001/2, the
4559 Hitachi H8/300, H8/500 and Super-H.
4561 * New targets supported
4563 H8/300 simulator h8300-hitachi-hms or h8300hms
4564 H8/500 simulator h8500-hitachi-hms or h8500hms
4565 SH simulator sh-hitachi-hms or sh
4566 Z8000 simulator z8k-zilog-none or z8ksim
4567 IDT MIPS board over serial line mips-idt-ecoff
4569 Cross-debugging to GO32 targets is supported. It requires a custom
4570 version of the i386-stub.c module which is integrated with the
4571 GO32 memory extender.
4573 * New remote protocols
4575 MIPS remote debugging protocol.
4577 * New source languages supported
4579 This version includes preliminary support for Chill, a Pascal like language
4580 used by telecommunications companies. Chill support is also being integrated
4581 into the GNU compiler, but we don't know when it will be publically available.
4584 *** Changes in GDB-4.8:
4586 * HP Precision Architecture supported
4588 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4589 version of this support was available as a set of patches from the
4590 University of Utah. GDB does not support debugging of programs
4591 compiled with the HP compiler, because HP will not document their file
4592 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4593 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4595 Many problems in the preliminary version have been fixed.
4597 * Faster and better demangling
4599 We have improved template demangling and fixed numerous bugs in the GNU style
4600 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4601 character types (wchar_t) are now supported. Demangling of each symbol is now
4602 only done once, and is cached when the symbol table for a file is read in.
4603 This results in a small increase in memory usage for C programs, a moderate
4604 increase in memory usage for C++ programs, and a fantastic speedup in
4607 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4608 from the specifications in the Annotated Reference Manual, which AT&T's
4609 compiler does not actually implement.
4611 * G++ multiple inheritance compiler problem
4613 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4614 inheritance lattices was reworked to properly discover ambiguities. We
4615 recently found an example which causes this new algorithm to fail in a
4616 very subtle way, producing bad debug information for those classes.
4617 The file 'gcc.patch' (in this directory) can be applied to gcc to
4618 circumvent the problem. A future GCC release will contain a complete
4621 The previous G++ debug info problem (mentioned below for the gdb-4.7
4622 release) is fixed in gcc version 2.3.2.
4624 * Improved configure script
4626 The `configure' script will now attempt to guess your system type if
4627 you don't supply a host system type. The old scheme of supplying a
4628 host system triplet is preferable over using this. All the magic is
4629 done in the new `config.guess' script. Examine it for details.
4631 We have also brought our configure script much more in line with the FSF's
4632 version. It now supports the --with-xxx options. In particular,
4633 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4634 The resulting GDB will not be able to read arbitrary object file formats --
4635 only the format ``expected'' to be used on the configured target system.
4636 We hope to make this the default in a future release.
4638 * Documentation improvements
4640 There's new internal documentation on how to modify GDB, and how to
4641 produce clean changes to the code. We implore people to read it
4642 before submitting changes.
4644 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4645 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4646 `info' files are also provided. To build `info' files from scratch,
4647 you will need the latest `makeinfo' release, which will be available in
4648 a future texinfo-X.Y release.
4650 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4651 We're not sure exactly which versions have this problem, but it has
4652 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4653 or better. If that isn't possible, there is a patch in
4654 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4655 around this problem.
4659 GDB now supports array constants that can be used in expressions typed in by
4660 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4661 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4664 The new directory `gdb/sparclite' contains a program that demonstrates
4665 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4667 * New native hosts supported
4669 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4670 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4672 * New targets supported
4674 AMD 29k family via UDI a29k-amd-udi or udi29k
4676 * New file formats supported
4678 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4679 HPUX core files, and SCO 3.2v2 core files.
4683 Attaching to processes now works again; thanks for the many bug reports.
4685 We have also stomped on a bunch of core dumps caused by
4686 printf_filtered("%s") problems.
4688 We eliminated a copyright problem on the rpc and ptrace header files
4689 for VxWorks, which was discovered at the last minute during the 4.7
4690 release. You should now be able to build a VxWorks GDB.
4692 You can now interrupt gdb while an attached process is running. This
4693 will cause the attached process to stop, and give control back to GDB.
4695 We fixed problems caused by using too many file descriptors
4696 for reading symbols from object files and libraries. This was
4697 especially a problem for programs that used many (~100) shared
4700 The `step' command now only enters a subroutine if there is line number
4701 information for the subroutine. Otherwise it acts like the `next'
4702 command. Previously, `step' would enter subroutines if there was
4703 any debugging information about the routine. This avoids problems
4704 when using `cc -g1' on MIPS machines.
4706 * Internal improvements
4708 GDB's internal interfaces have been improved to make it easier to support
4709 debugging of multiple languages in the future.
4711 GDB now uses a common structure for symbol information internally.
4712 Minimal symbols (derived from linkage symbols in object files), partial
4713 symbols (from a quick scan of debug information), and full symbols
4714 contain a common subset of information, making it easier to write
4715 shared code that handles any of them.
4717 * New command line options
4719 We now accept --silent as an alias for --quiet.
4723 The memory-mapped-malloc library is now licensed under the GNU Library
4724 General Public License.
4726 *** Changes in GDB-4.7:
4728 * Host/native/target split
4730 GDB has had some major internal surgery to untangle the support for
4731 hosts and remote targets. Now, when you configure GDB for a remote
4732 target, it will no longer load in all of the support for debugging
4733 local programs on the host. When fully completed and tested, this will
4734 ensure that arbitrary host/target combinations are possible.
4736 The primary conceptual shift is to separate the non-portable code in
4737 GDB into three categories. Host specific code is required any time GDB
4738 is compiled on that host, regardless of the target. Target specific
4739 code relates to the peculiarities of the target, but can be compiled on
4740 any host. Native specific code is everything else: it can only be
4741 built when the host and target are the same system. Child process
4742 handling and core file support are two common `native' examples.
4744 GDB's use of /proc for controlling Unix child processes is now cleaner.
4745 It has been split out into a single module under the `target_ops' vector,
4746 plus two native-dependent functions for each system that uses /proc.
4748 * New hosts supported
4750 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4751 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4752 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4754 * New targets supported
4756 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4757 68030 and CPU32 m68030-*-*, m68332-*-*
4759 * New native hosts supported
4761 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4762 (386bsd is not well tested yet)
4763 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4765 * New file formats supported
4767 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4768 supports reading of `a.out.adobe' object files, which are an a.out
4769 format extended with minimal information about multiple sections.
4773 `show copying' is the same as the old `info copying'.
4774 `show warranty' is the same as `info warrantee'.
4775 These were renamed for consistency. The old commands continue to work.
4777 `info handle' is a new alias for `info signals'.
4779 You can now define pre-command hooks, which attach arbitrary command
4780 scripts to any command. The commands in the hook will be executed
4781 prior to the user's command. You can also create a hook which will be
4782 executed whenever the program stops. See gdb.texinfo.
4786 We now deal with Cfront style name mangling, and can even extract type
4787 info from mangled symbols. GDB can automatically figure out which
4788 symbol mangling style your C++ compiler uses.
4790 Calling of methods and virtual functions has been improved as well.
4794 The crash that occured when debugging Sun Ansi-C compiled binaries is
4795 fixed. This was due to mishandling of the extra N_SO stabs output
4798 We also finally got Ultrix 4.2 running in house, and fixed core file
4799 support, with help from a dozen people on the net.
4801 John M. Farrell discovered that the reason that single-stepping was so
4802 slow on all of the Mips based platforms (primarily SGI and DEC) was
4803 that we were trying to demangle and lookup a symbol used for internal
4804 purposes on every instruction that was being stepped through. Changing
4805 the name of that symbol so that it couldn't be mistaken for a C++
4806 mangled symbol sped things up a great deal.
4808 Rich Pixley sped up symbol lookups in general by getting much smarter
4809 about when C++ symbol mangling is necessary. This should make symbol
4810 completion (TAB on the command line) much faster. It's not as fast as
4811 we'd like, but it's significantly faster than gdb-4.6.
4815 A new user controllable variable 'call_scratch_address' can
4816 specify the location of a scratch area to be used when GDB
4817 calls a function in the target. This is necessary because the
4818 usual method of putting the scratch area on the stack does not work
4819 in systems that have separate instruction and data spaces.
4821 We integrated changes to support the 29k UDI (Universal Debugger
4822 Interface), but discovered at the last minute that we didn't have all
4823 of the appropriate copyright paperwork. We are working with AMD to
4824 resolve this, and hope to have it available soon.
4828 We have sped up the remote serial line protocol, especially for targets
4829 with lots of registers. It now supports a new `expedited status' ('T')
4830 message which can be used in place of the existing 'S' status message.
4831 This allows the remote stub to send only the registers that GDB
4832 needs to make a quick decision about single-stepping or conditional
4833 breakpoints, eliminating the need to fetch the entire register set for
4834 each instruction being stepped through.
4836 The GDB remote serial protocol now implements a write-through cache for
4837 registers, only re-reading the registers if the target has run.
4839 There is also a new remote serial stub for SPARC processors. You can
4840 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4841 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4842 processor with a serial port.
4846 Configure.in files have become much easier to read and modify. A new
4847 `table driven' format makes it more obvious what configurations are
4848 supported, and what files each one uses.
4852 There is a new opcodes library which will eventually contain all of the
4853 disassembly routines and opcode tables. At present, it only contains
4854 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4855 disassembler (binutils/objdump) to share these routines.
4857 The libiberty library is now copylefted under the GNU Library General
4858 Public License. This allows more liberal use, and was done so libg++
4859 can use it. This makes no difference to GDB, since the Library License
4860 grants all the rights from the General Public License.
4864 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4865 reference to the stabs symbol info used by the debugger. It is (as far
4866 as we know) the only published document on this fascinating topic. We
4867 encourage you to read it, compare it to the stabs information on your
4868 system, and send improvements on the document in general (to
4869 bug-gdb@prep.ai.mit.edu).
4871 And, of course, many bugs have been fixed.
4874 *** Changes in GDB-4.6:
4876 * Better support for C++ function names
4878 GDB now accepts as input the "demangled form" of C++ overloaded function
4879 names and member function names, and can do command completion on such names
4880 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4881 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4882 Make use of command completion, it is your friend.
4884 GDB also now accepts a variety of C++ mangled symbol formats. They are
4885 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4886 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4887 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4888 for the list of formats.
4890 * G++ symbol mangling problem
4892 Recent versions of gcc have a bug in how they emit debugging information for
4893 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4894 directory) can be applied to gcc to fix the problem. Alternatively, if you
4895 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4896 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4897 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4900 * New 'maintenance' command
4902 All of the commands related to hacking GDB internals have been moved out of
4903 the main command set, and now live behind the 'maintenance' command. This
4904 can also be abbreviated as 'mt'. The following changes were made:
4906 dump-me -> maintenance dump-me
4907 info all-breakpoints -> maintenance info breakpoints
4908 printmsyms -> maintenance print msyms
4909 printobjfiles -> maintenance print objfiles
4910 printpsyms -> maintenance print psymbols
4911 printsyms -> maintenance print symbols
4913 The following commands are new:
4915 maintenance demangle Call internal GDB demangler routine to
4916 demangle a C++ link name and prints the result.
4917 maintenance print type Print a type chain for a given symbol
4919 * Change to .gdbinit file processing
4921 We now read the $HOME/.gdbinit file before processing the argv arguments
4922 (e.g. reading symbol files or core files). This allows global parameters to
4923 be set, which will apply during the symbol reading. The ./.gdbinit is still
4924 read after argv processing.
4926 * New hosts supported
4928 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4930 GNU/Linux support i386-unknown-linux or linux
4932 We are also including code to support the HP/PA running BSD and HPUX. This
4933 is almost guaranteed not to work, as we didn't have time to test or build it
4934 for this release. We are including it so that the more adventurous (or
4935 masochistic) of you can play with it. We also had major problems with the
4936 fact that the compiler that we got from HP doesn't support the -g option.
4939 * New targets supported
4941 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4943 * More smarts about finding #include files
4945 GDB now remembers the compilation directory for all include files, and for
4946 all files from which C is generated (like yacc and lex sources). This
4947 greatly improves GDB's ability to find yacc/lex sources, and include files,
4948 especially if you are debugging your program from a directory different from
4949 the one that contains your sources.
4951 We also fixed a bug which caused difficulty with listing and setting
4952 breakpoints in include files which contain C code. (In the past, you had to
4953 try twice in order to list an include file that you hadn't looked at before.)
4955 * Interesting infernals change
4957 GDB now deals with arbitrary numbers of sections, where the symbols for each
4958 section must be relocated relative to that section's landing place in the
4959 target's address space. This work was needed to support ELF with embedded
4960 stabs used by Solaris-2.0.
4962 * Bug fixes (of course!)
4964 There have been loads of fixes for the following things:
4965 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4966 i960, stabs, DOS(GO32), procfs, etc...
4968 See the ChangeLog for details.
4970 *** Changes in GDB-4.5:
4972 * New machines supported (host and target)
4974 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4976 SGI Irix-4.x mips-sgi-irix4 or iris4
4978 * New malloc package
4980 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4981 Mmalloc is capable of handling mutiple heaps of memory. It is also
4982 capable of saving a heap to a file, and then mapping it back in later.
4983 This can be used to greatly speedup the startup of GDB by using a
4984 pre-parsed symbol table which lives in a mmalloc managed heap. For
4985 more details, please read mmalloc/mmalloc.texi.
4989 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4990 'help info proc' for details.
4992 * MIPS ecoff symbol table format
4994 The code that reads MIPS symbol table format is now supported on all hosts.
4995 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4998 * File name changes for MS-DOS
5000 Many files in the config directories have been renamed to make it easier to
5001 support GDB on MS-DOSe systems (which have very restrictive file name
5002 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
5003 environment) is close to working but has some remaining problems. Note
5004 that debugging of DOS programs is not supported, due to limitations
5005 in the ``operating system'', but it can be used to host cross-debugging.
5007 * Cross byte order fixes
5009 Many fixes have been made to support cross debugging of Sparc and MIPS
5010 targets from hosts whose byte order differs.
5012 * New -mapped and -readnow options
5014 If memory-mapped files are available on your system through the 'mmap'
5015 system call, you can use the -mapped option on the `file' or
5016 `symbol-file' commands to cause GDB to write the symbols from your
5017 program into a reusable file. If the program you are debugging is
5018 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5019 Future GDB debugging sessions will notice the presence of this file,
5020 and will quickly map in symbol information from it, rather than reading
5021 the symbol table from the executable program. Using the '-mapped'
5022 option in a GDB `file' or `symbol-file' command has the same effect as
5023 starting GDB with the '-mapped' command-line option.
5025 You can cause GDB to read the entire symbol table immediately by using
5026 the '-readnow' option with any of the commands that load symbol table
5027 information (or on the GDB command line). This makes the command
5028 slower, but makes future operations faster.
5030 The -mapped and -readnow options are typically combined in order to
5031 build a `fred.syms' file that contains complete symbol information.
5032 A simple GDB invocation to do nothing but build a `.syms' file for future
5035 gdb -batch -nx -mapped -readnow programname
5037 The `.syms' file is specific to the host machine on which GDB is run.
5038 It holds an exact image of GDB's internal symbol table. It cannot be
5039 shared across multiple host platforms.
5041 * longjmp() handling
5043 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5044 siglongjmp() without losing control. This feature has not yet been ported to
5045 all systems. It currently works on many 386 platforms, all MIPS-based
5046 platforms (SGI, DECstation, etc), and Sun3/4.
5050 Preliminary work has been put in to support the new Solaris OS from Sun. At
5051 this time, it can control and debug processes, but it is not capable of
5056 As always, many many bug fixes. The major areas were with g++, and mipsread.
5057 People using the MIPS-based platforms should experience fewer mysterious
5058 crashes and trashed symbol tables.
5060 *** Changes in GDB-4.4:
5062 * New machines supported (host and target)
5064 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5066 BSD Reno on Vax vax-dec-bsd
5067 Ultrix on Vax vax-dec-ultrix
5069 * New machines supported (target)
5071 AMD 29000 embedded, using EBMON a29k-none-none
5075 GDB continues to improve its handling of C++. `References' work better.
5076 The demangler has also been improved, and now deals with symbols mangled as
5077 per the Annotated C++ Reference Guide.
5079 GDB also now handles `stabs' symbol information embedded in MIPS
5080 `ecoff' symbol tables. Since the ecoff format was not easily
5081 extensible to handle new languages such as C++, this appeared to be a
5082 good way to put C++ debugging info into MIPS binaries. This option
5083 will be supported in the GNU C compiler, version 2, when it is
5086 * New features for SVR4
5088 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5089 shared libraries. Debugging dynamically linked programs should present
5090 only minor differences from debugging statically linked programs.
5092 The `info proc' command will print out information about any process
5093 on an SVR4 system (including the one you are debugging). At the moment,
5094 it prints the address mappings of the process.
5096 If you bring up GDB on another SVR4 system, please send mail to
5097 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5099 * Better dynamic linking support in SunOS
5101 Reading symbols from shared libraries which contain debugging symbols
5102 now works properly. However, there remain issues such as automatic
5103 skipping of `transfer vector' code during function calls, which
5104 make it harder to debug code in a shared library, than to debug the
5105 same code linked statically.
5109 GDB is now using the latest `getopt' routines from the FSF. This
5110 version accepts the -- prefix for options with long names. GDB will
5111 continue to accept the old forms (-option and +option) as well.
5112 Various single letter abbreviations for options have been explicity
5113 added to the option table so that they won't get overshadowed in the
5114 future by other options that begin with the same letter.
5118 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5119 Many assorted bugs have been handled. Many more remain to be handled.
5120 See the various ChangeLog files (primarily in gdb and bfd) for details.
5123 *** Changes in GDB-4.3:
5125 * New machines supported (host and target)
5127 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5128 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5129 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5131 * Almost SCO Unix support
5133 We had hoped to support:
5134 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5135 (except for core file support), but we discovered very late in the release
5136 that it has problems with process groups that render gdb unusable. Sorry
5137 about that. I encourage people to fix it and post the fixes.
5139 * Preliminary ELF and DWARF support
5141 GDB can read ELF object files on System V Release 4, and can handle
5142 debugging records for C, in DWARF format, in ELF files. This support
5143 is preliminary. If you bring up GDB on another SVR4 system, please
5144 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5149 GDB now uses the latest `readline' library. One user-visible change
5150 is that two tabs will list possible command completions, which previously
5151 required typing M-? (meta-question mark, or ESC ?).
5155 The `stepi' bug that many of you noticed has been squashed.
5156 Many bugs in C++ have been handled. Many more remain to be handled.
5157 See the various ChangeLog files (primarily in gdb and bfd) for details.
5159 * State of the MIPS world (in case you wondered):
5161 GDB can understand the symbol tables emitted by the compilers
5162 supplied by most vendors of MIPS-based machines, including DEC. These
5163 symbol tables are in a format that essentially nobody else uses.
5165 Some versions of gcc come with an assembler post-processor called
5166 mips-tfile. This program is required if you want to do source-level
5167 debugging of gcc-compiled programs. I believe FSF does not ship
5168 mips-tfile with gcc version 1, but it will eventually come with gcc
5171 Debugging of g++ output remains a problem. g++ version 1.xx does not
5172 really support it at all. (If you're lucky, you should be able to get
5173 line numbers and stack traces to work, but no parameters or local
5174 variables.) With some work it should be possible to improve the
5177 When gcc version 2 is released, you will have somewhat better luck.
5178 However, even then you will get confusing results for inheritance and
5181 We will eventually provide full debugging of g++ output on
5182 DECstations. This will probably involve some kind of stabs-in-ecoff
5183 encapulation, but the details have not been worked out yet.
5186 *** Changes in GDB-4.2:
5188 * Improved configuration
5190 Only one copy of `configure' exists now, and it is not self-modifying.
5191 Porting BFD is simpler.
5195 The `step' and `next' commands now only stop at the first instruction
5196 of a source line. This prevents the multiple stops that used to occur
5197 in switch statements, for-loops, etc. `Step' continues to stop if a
5198 function that has debugging information is called within the line.
5202 Lots of small bugs fixed. More remain.
5204 * New host supported (not target)
5206 Intel 386 PC clone running Mach i386-none-mach
5209 *** Changes in GDB-4.1:
5211 * Multiple source language support
5213 GDB now has internal scaffolding to handle several source languages.
5214 It determines the type of each source file from its filename extension,
5215 and will switch expression parsing and number formatting to match the
5216 language of the function in the currently selected stack frame.
5217 You can also specifically set the language to be used, with
5218 `set language c' or `set language modula-2'.
5222 GDB now has preliminary support for the GNU Modula-2 compiler,
5223 currently under development at the State University of New York at
5224 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5225 continue through the fall of 1991 and into 1992.
5227 Other Modula-2 compilers are currently not supported, and attempting to
5228 debug programs compiled with them will likely result in an error as the
5229 symbol table is read. Feel free to work on it, though!
5231 There are hooks in GDB for strict type checking and range checking,
5232 in the `Modula-2 philosophy', but they do not currently work.
5236 GDB can now write to executable and core files (e.g. patch
5237 a variable's value). You must turn this switch on, specify
5238 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5239 by assigning a new value to a variable. Modifications take
5242 * Automatic SunOS shared library reading
5244 When you run your program, GDB automatically determines where its
5245 shared libraries (if any) have been loaded, and reads their symbols.
5246 The `share' command is no longer needed. This also works when
5247 examining core files.
5251 You can specify the number of lines that the `list' command shows.
5254 * New machines supported (host and target)
5256 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5257 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5258 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5260 * New hosts supported (not targets)
5262 IBM RT/PC: romp-ibm-aix or rtpc
5264 * New targets supported (not hosts)
5266 AMD 29000 embedded with COFF a29k-none-coff
5267 AMD 29000 embedded with a.out a29k-none-aout
5268 Ultracomputer remote kernel debug a29k-nyu-kern
5270 * New remote interfaces
5276 *** Changes in GDB-4.0:
5280 Wide output is wrapped at good places to make the output more readable.
5282 Gdb now supports cross-debugging from a host machine of one type to a
5283 target machine of another type. Communication with the target system
5284 is over serial lines. The ``target'' command handles connecting to the
5285 remote system; the ``load'' command will download a program into the
5286 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5287 also supports debugging of realtime processes running under VxWorks,
5288 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5289 stub on the target system.
5291 New CPUs supported include the AMD 29000 and Intel 960.
5293 GDB now reads object files and symbol tables via a ``binary file''
5294 library, which allows a single copy of GDB to debug programs of multiple
5295 object file types such as a.out and coff.
5297 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5298 refcard.dvi and refcard.ps are available to format it).
5301 * Control-Variable user interface simplified
5303 All variables that control the operation of the debugger can be set
5304 by the ``set'' command, and displayed by the ``show'' command.
5306 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5307 ``Show prompt'' produces the response:
5308 Gdb's prompt is new-gdb=>.
5310 What follows are the NEW set commands. The command ``help set'' will
5311 print a complete list of old and new set commands. ``help set FOO''
5312 will give a longer description of the variable FOO. ``show'' will show
5313 all of the variable descriptions and their current settings.
5315 confirm on/off: Enables warning questions for operations that are
5316 hard to recover from, e.g. rerunning the program while
5317 it is already running. Default is ON.
5319 editing on/off: Enables EMACS style command line editing
5320 of input. Previous lines can be recalled with
5321 control-P, the current line can be edited with control-B,
5322 you can search for commands with control-R, etc.
5325 history filename NAME: NAME is where the gdb command history
5326 will be stored. The default is .gdb_history,
5327 or the value of the environment variable
5330 history size N: The size, in commands, of the command history. The
5331 default is 256, or the value of the environment variable
5334 history save on/off: If this value is set to ON, the history file will
5335 be saved after exiting gdb. If set to OFF, the
5336 file will not be saved. The default is OFF.
5338 history expansion on/off: If this value is set to ON, then csh-like
5339 history expansion will be performed on
5340 command line input. The default is OFF.
5342 radix N: Sets the default radix for input and output. It can be set
5343 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5344 in the current radix, so "set radix 10" is always a no-op.
5346 height N: This integer value is the number of lines on a page. Default
5347 is 24, the current `stty rows'' setting, or the ``li#''
5348 setting from the termcap entry matching the environment
5351 width N: This integer value is the number of characters on a line.
5352 Default is 80, the current `stty cols'' setting, or the ``co#''
5353 setting from the termcap entry matching the environment
5356 Note: ``set screensize'' is obsolete. Use ``set height'' and
5357 ``set width'' instead.
5359 print address on/off: Print memory addresses in various command displays,
5360 such as stack traces and structure values. Gdb looks
5361 more ``symbolic'' if you turn this off; it looks more
5362 ``machine level'' with it on. Default is ON.
5364 print array on/off: Prettyprint arrays. New convenient format! Default
5367 print demangle on/off: Print C++ symbols in "source" form if on,
5370 print asm-demangle on/off: Same, for assembler level printouts
5373 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5376 * Support for Epoch Environment.
5378 The epoch environment is a version of Emacs v18 with windowing. One
5379 new command, ``inspect'', is identical to ``print'', except that if you
5380 are running in the epoch environment, the value is printed in its own
5384 * Support for Shared Libraries
5386 GDB can now debug programs and core files that use SunOS shared libraries.
5387 Symbols from a shared library cannot be referenced
5388 before the shared library has been linked with the program (this
5389 happens after you type ``run'' and before the function main() is entered).
5390 At any time after this linking (including when examining core files
5391 from dynamically linked programs), gdb reads the symbols from each
5392 shared library when you type the ``sharedlibrary'' command.
5393 It can be abbreviated ``share''.
5395 sharedlibrary REGEXP: Load shared object library symbols for files
5396 matching a unix regular expression. No argument
5397 indicates to load symbols for all shared libraries.
5399 info sharedlibrary: Status of loaded shared libraries.
5404 A watchpoint stops execution of a program whenever the value of an
5405 expression changes. Checking for this slows down execution
5406 tremendously whenever you are in the scope of the expression, but is
5407 quite useful for catching tough ``bit-spreader'' or pointer misuse
5408 problems. Some machines such as the 386 have hardware for doing this
5409 more quickly, and future versions of gdb will use this hardware.
5411 watch EXP: Set a watchpoint (breakpoint) for an expression.
5413 info watchpoints: Information about your watchpoints.
5415 delete N: Deletes watchpoint number N (same as breakpoints).
5416 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5417 enable N: Re-enables watchpoint number N (same as breakpoints).
5420 * C++ multiple inheritance
5422 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5425 * C++ exception handling
5427 Gdb now supports limited C++ exception handling. Besides the existing
5428 ability to breakpoint on an exception handler, gdb can breakpoint on
5429 the raising of an exception (before the stack is peeled back to the
5432 catch FOO: If there is a FOO exception handler in the dynamic scope,
5433 set a breakpoint to catch exceptions which may be raised there.
5434 Multiple exceptions (``catch foo bar baz'') may be caught.
5436 info catch: Lists all exceptions which may be caught in the
5437 current stack frame.
5440 * Minor command changes
5442 The command ``call func (arg, arg, ...)'' now acts like the print
5443 command, except it does not print or save a value if the function's result
5444 is void. This is similar to dbx usage.
5446 The ``up'' and ``down'' commands now always print the frame they end up
5447 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5448 frames without printing.
5450 * New directory command
5452 'dir' now adds directories to the FRONT of the source search path.
5453 The path starts off empty. Source files that contain debug information
5454 about the directory in which they were compiled can be found even
5455 with an empty path; Sun CC and GCC include this information. If GDB can't
5456 find your source file in the current directory, type "dir .".
5458 * Configuring GDB for compilation
5460 For normal use, type ``./configure host''. See README or gdb.texinfo
5463 GDB now handles cross debugging. If you are remotely debugging between
5464 two different machines, type ``./configure host -target=targ''.
5465 Host is the machine where GDB will run; targ is the machine
5466 where the program that you are debugging will run.