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 * New system-wide configuration scripts
97 A GDB installation now provides scripts suitable for use as system-wide
98 configuration scripts for the following systems:
102 * GDB now supports target-assigned range stepping with remote targets.
103 This improves the performance of stepping source lines by reducing
104 the number of control packets from/to GDB. See "New remote packets"
107 * GDB now understands the element 'tvar' in the XML traceframe info.
108 It has the id of the collected trace state variables.
114 The vCont packet supports a new 'r' action, that tells the remote
115 stub to step through an address range itself, without GDB
116 involvemement at each single-step.
118 qXfer:libraries-svr4:read's annex
119 The previously unused annex of the qXfer:libraries-svr4:read packet
120 is now used to support passing an argument list. The remote stub
121 reports support for this argument list to GDB's qSupported query.
122 The defined arguments are "start" and "prev", used to reduce work
123 necessary for library list updating, resulting in significant
126 * New features in the GDB remote stub, GDBserver
128 ** GDBserver now supports target-assisted range stepping. Currently
129 enabled on x86/x86_64 GNU/Linux targets.
131 ** GDBserver now adds element 'tvar' in the XML in the reply to
132 'qXfer:traceframe-info:read'. It has the id of the collected
133 trace state variables.
135 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
138 * New 'z' formatter for printing and examining memory, this displays the
139 value as hexadecimal zero padded on the left to the size of the type.
141 *** Changes in GDB 7.6
143 * Target record has been renamed to record-full.
144 Record/replay is now enabled with the "record full" command.
145 This also affects settings that are associated with full record/replay
146 that have been moved from "set/show record" to "set/show record full":
148 set|show record full insn-number-max
149 set|show record full stop-at-limit
150 set|show record full memory-query
152 * A new record target "record-btrace" has been added. The new target
153 uses hardware support to record the control-flow of a process. It
154 does not support replaying the execution, but it implements the
155 below new commands for investigating the recorded execution log.
156 This new recording method can be enabled using:
160 The "record-btrace" target is only available on Intel Atom processors
161 and requires a Linux kernel 2.6.32 or later.
163 * Two new commands have been added for record/replay to give information
164 about the recorded execution without having to replay the execution.
165 The commands are only supported by "record btrace".
167 record instruction-history prints the execution history at
168 instruction granularity
170 record function-call-history prints the execution history at
173 * New native configurations
175 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
176 FreeBSD/powerpc powerpc*-*-freebsd
177 x86_64/Cygwin x86_64-*-cygwin*
178 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
182 ARM AArch64 aarch64*-*-elf
183 ARM AArch64 GNU/Linux aarch64*-*-linux
184 Lynx 178 PowerPC powerpc-*-lynx*178
185 x86_64/Cygwin x86_64-*-cygwin*
186 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
188 * If the configured location of system.gdbinit file (as given by the
189 --with-system-gdbinit option at configure time) is in the
190 data-directory (as specified by --with-gdb-datadir at configure
191 time) or in one of its subdirectories, then GDB will look for the
192 system-wide init file in the directory specified by the
193 --data-directory command-line option.
195 * New command line options:
197 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
198 other initialization files, unlike -nx which disables all of them.
200 * Removed command line options
202 -epoch This was used by the gdb mode in Epoch, an ancient fork of
205 * The 'ptype' and 'whatis' commands now accept an argument to control
208 * 'info proc' now works on some core files.
212 ** Vectors can be created with gdb.Type.vector.
214 ** Python's atexit.register now works in GDB.
216 ** Types can be pretty-printed via a Python API.
218 ** Python 3 is now supported (in addition to Python 2.4 or later)
220 ** New class gdb.Architecture exposes GDB's internal representation
221 of architecture in the Python API.
223 ** New method Frame.architecture returns the gdb.Architecture object
224 corresponding to the frame's architecture.
226 * New Python-based convenience functions:
228 ** $_memeq(buf1, buf2, length)
229 ** $_streq(str1, str2)
231 ** $_regex(str, regex)
233 * The 'cd' command now defaults to using '~' (the home directory) if not
236 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
237 default for GCC since November 2000.
239 * The command 'forward-search' can now be abbreviated as 'fo'.
241 * The command 'info tracepoints' can now display 'installed on target'
242 or 'not installed on target' for each non-pending location of tracepoint.
244 * New configure options
246 --enable-libmcheck/--disable-libmcheck
247 By default, development versions are built with -lmcheck on hosts
248 that support it, in order to help track memory corruption issues.
249 Release versions, on the other hand, are built without -lmcheck
250 by default. The --enable-libmcheck/--disable-libmcheck configure
251 options allow the user to override that default.
252 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
253 This configure option allows the user to build GDB with
254 libbabeltrace using which GDB can read Common Trace Format data.
256 * New commands (for set/show, see "New options" below)
259 Catch signals. This is similar to "handle", but allows commands and
260 conditions to be attached.
263 List the BFDs known to GDB.
265 python-interactive [command]
267 Start a Python interactive prompt, or evaluate the optional command
268 and print the result of expressions.
271 "py" is a new alias for "python".
273 enable type-printer [name]...
274 disable type-printer [name]...
275 Enable or disable type printers.
279 ** For the Renesas Super-H architecture, the "regs" command has been removed
280 (has been deprecated in GDB 7.5), and "info all-registers" should be used
285 set print type methods (on|off)
286 show print type methods
287 Control whether method declarations are displayed by "ptype".
288 The default is to show them.
290 set print type typedefs (on|off)
291 show print type typedefs
292 Control whether typedef definitions are displayed by "ptype".
293 The default is to show them.
295 set filename-display basename|relative|absolute
296 show filename-display
297 Control the way in which filenames is displayed.
298 The default is "relative", which preserves previous behavior.
300 set trace-buffer-size
301 show trace-buffer-size
302 Request target to change the size of trace buffer.
304 set remote trace-buffer-size-packet auto|on|off
305 show remote trace-buffer-size-packet
306 Control the use of the remote protocol `QTBuffer:size' packet.
310 Control display of debugging messages related to ARM AArch64.
313 set debug coff-pe-read
314 show debug coff-pe-read
315 Control display of debugging messages related to reading of COFF/PE
320 Control display of debugging messages related to Mach-O symbols
323 set debug notification
324 show debug notification
325 Control display of debugging info for async remote notification.
329 ** Command parameter changes are now notified using new async record
330 "=cmd-param-changed".
331 ** Trace frame changes caused by command "tfind" are now notified using
332 new async record "=traceframe-changed".
333 ** The creation, deletion and modification of trace state variables
334 are now notified using new async records "=tsv-created",
335 "=tsv-deleted" and "=tsv-modified".
336 ** The start and stop of process record are now notified using new
337 async record "=record-started" and "=record-stopped".
338 ** Memory changes are now notified using new async record
340 ** The data-disassemble command response will include a "fullname" field
341 containing the absolute file name when source has been requested.
342 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
343 command, to allow pattern filling of memory areas.
344 ** New commands "-catch-load"/"-catch-unload" added for intercepting
345 library load/unload events.
346 ** The response to breakpoint commands and breakpoint async records
347 includes an "installed" field containing a boolean state about each
348 non-pending tracepoint location is whether installed on target or not.
349 ** Output of the "-trace-status" command includes a "trace-file" field
350 containing the name of the trace file being examined. This field is
351 optional, and only present when examining a trace file.
352 ** The "fullname" field is now always present along with the "file" field,
353 even if the file cannot be found by GDB.
355 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
356 You must have the LZMA library available when configuring GDB for this
357 feature to be enabled. For more information, see:
358 http://fedoraproject.org/wiki/Features/MiniDebugInfo
363 Set the size of trace buffer. The remote stub reports support for this
364 packet to gdb's qSupported query.
367 Enable Branch Trace Store (BTS)-based branch tracing for the current
368 thread. The remote stub reports support for this packet to gdb's
372 Disable branch tracing for the current thread. The remote stub reports
373 support for this packet to gdb's qSupported query.
376 Read the traced branches for the current thread. The remote stub
377 reports support for this packet to gdb's qSupported query.
379 *** Changes in GDB 7.5
381 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
382 for more x32 ABI info.
384 * GDB now supports access to MIPS DSP registers on Linux targets.
386 * GDB now supports debugging microMIPS binaries.
388 * The "info os" command on GNU/Linux can now display information on
389 several new classes of objects managed by the operating system:
390 "info os procgroups" lists process groups
391 "info os files" lists file descriptors
392 "info os sockets" lists internet-domain sockets
393 "info os shm" lists shared-memory regions
394 "info os semaphores" lists semaphores
395 "info os msg" lists message queues
396 "info os modules" lists loaded kernel modules
398 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
399 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
400 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
401 options and inspect the probe arguments using the new $_probe_arg family
402 of convenience variables. You can obtain more information about SystemTap
403 in <http://sourceware.org/systemtap/>.
405 * GDB now supports reversible debugging on ARM, it allows you to
406 debug basic ARM and THUMB instructions, and provides
407 record/replay support.
409 * The option "symbol-reloading" has been deleted as it is no longer used.
413 ** GDB commands implemented in Python can now be put in command class
416 ** The "maint set python print-stack on|off" is now deleted.
418 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
419 apply "flag enum"-style pretty-printing to any enum.
421 ** gdb.lookup_symbol can now work when there is no current frame.
423 ** gdb.Symbol now has a 'line' attribute, holding the line number in
424 the source at which the symbol was defined.
426 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
427 method 'value'. The former indicates whether the symbol needs a
428 frame in order to compute its value, and the latter computes the
431 ** A new method 'referenced_value' on gdb.Value objects which can
432 dereference pointer as well as C++ reference values.
434 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
435 which return the global and static blocks (as gdb.Block objects),
436 of the underlying symbol table, respectively.
438 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
439 object associated with a PC value.
441 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
442 of the address range occupied by code for the current source line.
444 * Go language support.
445 GDB now supports debugging programs written in the Go programming
448 * GDBserver now supports stdio connections.
449 E.g. (gdb) target remote | ssh myhost gdbserver - hello
451 * The binary "gdbtui" can no longer be built or installed.
452 Use "gdb -tui" instead.
454 * GDB will now print "flag" enums specially. A flag enum is one where
455 all the enumerator values have no bits in common when pairwise
456 "and"ed. When printing a value whose type is a flag enum, GDB will
457 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
458 (gdb) print (enum E) 3
461 * The filename part of a linespec will now match trailing components
462 of a source file name. For example, "break gcc/expr.c:1000" will
463 now set a breakpoint in build/gcc/expr.c, but not
466 * The "info proc" and "generate-core-file" commands will now also
467 work on remote targets connected to GDBserver on Linux.
469 * The command "info catch" has been removed. It has been disabled
472 * The "catch exception" and "catch assert" commands now accept
473 a condition at the end of the command, much like the "break"
474 command does. For instance:
476 (gdb) catch exception Constraint_Error if Barrier = True
478 Previously, it was possible to add a condition to such catchpoints,
479 but it had to be done as a second step, after the catchpoint had been
480 created, using the "condition" command.
482 * The "info static-tracepoint-marker" command will now also work on
483 native Linux targets with in-process agent.
485 * GDB can now set breakpoints on inlined functions.
487 * The .gdb_index section has been updated to include symbols for
488 inlined functions. GDB will ignore older .gdb_index sections by
489 default, which could cause symbol files to be loaded more slowly
490 until their .gdb_index sections can be recreated. The new command
491 "set use-deprecated-index-sections on" will cause GDB to use any older
492 .gdb_index sections it finds. This will restore performance, but the
493 ability to set breakpoints on inlined functions will be lost in symbol
494 files with older .gdb_index sections.
496 The .gdb_index section has also been updated to record more information
497 about each symbol. This speeds up the "info variables", "info functions"
498 and "info types" commands when used with programs having the .gdb_index
499 section, as well as speeding up debugging with shared libraries using
500 the .gdb_index section.
502 * Ada support for GDB/MI Variable Objects has been added.
504 * GDB can now support 'breakpoint always-inserted mode' in 'record'
509 ** New command -info-os is the MI equivalent of "info os".
511 ** Output logs ("set logging" and related) now include MI output.
515 ** "set use-deprecated-index-sections on|off"
516 "show use-deprecated-index-sections on|off"
517 Controls the use of deprecated .gdb_index sections.
519 ** "catch load" and "catch unload" can be used to stop when a shared
520 library is loaded or unloaded, respectively.
522 ** "enable count" can be used to auto-disable a breakpoint after
525 ** "info vtbl" can be used to show the virtual method tables for
526 C++ and Java objects.
528 ** "explore" and its sub commands "explore value" and "explore type"
529 can be used to reccursively explore values and types of
530 expressions. These commands are available only if GDB is
531 configured with '--with-python'.
533 ** "info auto-load" shows status of all kinds of auto-loaded files,
534 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
535 sequences of commands files, "info auto-load python-scripts"
536 shows status of auto-loading Python script files,
537 "info auto-load local-gdbinit" shows status of loading init file
538 (.gdbinit) from current directory and "info auto-load libthread-db" shows
539 status of inferior specific thread debugging shared library loading.
541 ** "info auto-load-scripts", "set auto-load-scripts on|off"
542 and "show auto-load-scripts" commands have been deprecated, use their
543 "info auto-load python-scripts", "set auto-load python-scripts on|off"
544 and "show auto-load python-scripts" counterparts instead.
546 ** "dprintf location,format,args..." creates a dynamic printf, which
547 is basically a breakpoint that does a printf and immediately
548 resumes your program's execution, so it is like a printf that you
549 can insert dynamically at runtime instead of at compiletime.
551 ** "set print symbol"
553 Controls whether GDB attempts to display the symbol, if any,
554 corresponding to addresses it prints. This defaults to "on", but
555 you can set it to "off" to restore GDB's previous behavior.
557 * Deprecated commands
559 ** For the Renesas Super-H architecture, the "regs" command has been
560 deprecated, and "info all-registers" should be used instead.
564 Renesas RL78 rl78-*-elf
565 HP OpenVMS ia64 ia64-hp-openvms*
567 * GDBserver supports evaluation of breakpoint conditions. When
568 support is advertised by GDBserver, GDB may be told to send the
569 breakpoint conditions in bytecode form to GDBserver. GDBserver
570 will only report the breakpoint trigger to GDB when its condition
576 show mips compression
577 Select the compressed ISA encoding used in functions that have no symbol
578 information available. The encoding can be set to either of:
581 and is updated automatically from ELF file flags if available.
583 set breakpoint condition-evaluation
584 show breakpoint condition-evaluation
585 Control whether breakpoint conditions are evaluated by GDB ("host") or by
586 GDBserver ("target"). Default option "auto" chooses the most efficient
588 This option can improve debugger efficiency depending on the speed of the
592 Disable auto-loading globally.
595 Show auto-loading setting of all kinds of auto-loaded files.
597 set auto-load gdb-scripts on|off
598 show auto-load gdb-scripts
599 Control auto-loading of GDB canned sequences of commands files.
601 set auto-load python-scripts on|off
602 show auto-load python-scripts
603 Control auto-loading of Python script files.
605 set auto-load local-gdbinit on|off
606 show auto-load local-gdbinit
607 Control loading of init file (.gdbinit) from current directory.
609 set auto-load libthread-db on|off
610 show auto-load libthread-db
611 Control auto-loading of inferior specific thread debugging shared library.
613 set auto-load scripts-directory <dir1>[:<dir2>...]
614 show auto-load scripts-directory
615 Set a list of directories from which to load auto-loaded scripts.
616 Automatically loaded Python scripts and GDB scripts are located in one
617 of the directories listed by this option.
618 The delimiter (':' above) may differ according to the host platform.
620 set auto-load safe-path <dir1>[:<dir2>...]
621 show auto-load safe-path
622 Set a list of directories from which it is safe to auto-load files.
623 The delimiter (':' above) may differ according to the host platform.
625 set debug auto-load on|off
627 Control display of debugging info for auto-loading the files above.
629 set dprintf-style gdb|call|agent
631 Control the way in which a dynamic printf is performed; "gdb"
632 requests a GDB printf command, while "call" causes dprintf to call a
633 function in the inferior. "agent" requests that the target agent
634 (such as GDBserver) do the printing.
636 set dprintf-function <expr>
637 show dprintf-function
638 set dprintf-channel <expr>
640 Set the function and optional first argument to the call when using
641 the "call" style of dynamic printf.
643 set disconnected-dprintf on|off
644 show disconnected-dprintf
645 Control whether agent-style dynamic printfs continue to be in effect
646 after GDB disconnects.
648 * New configure options
651 Configure default value for the 'set auto-load scripts-directory'
652 setting above. It defaults to '$debugdir:$datadir/auto-load',
653 $debugdir representing global debugging info directories (available
654 via 'show debug-file-directory') and $datadir representing GDB's data
655 directory (available via 'show data-directory').
657 --with-auto-load-safe-path
658 Configure default value for the 'set auto-load safe-path' setting
659 above. It defaults to the --with-auto-load-dir setting.
661 --without-auto-load-safe-path
662 Set 'set auto-load safe-path' to '/', effectively disabling this
667 z0/z1 conditional breakpoints extension
669 The z0/z1 breakpoint insertion packets have been extended to carry
670 a list of conditional expressions over to the remote stub depending on the
671 condition evaluation mode. The use of this extension can be controlled
672 via the "set remote conditional-breakpoints-packet" command.
676 Specify the signals which the remote stub may pass to the debugged
677 program without GDB involvement.
679 * New command line options
681 --init-command=FILE, -ix Like --command, -x but execute it
682 before loading inferior.
683 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
684 execute it before loading inferior.
686 *** Changes in GDB 7.4
688 * GDB now handles ambiguous linespecs more consistently; the existing
689 FILE:LINE support has been expanded to other types of linespecs. A
690 breakpoint will now be set on all matching locations in all
691 inferiors, and locations will be added or removed according to
694 * GDB now allows you to skip uninteresting functions and files when
695 stepping with the "skip function" and "skip file" commands.
697 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
698 and "show remote hardware-watchpoint-length-limit". These allows to
699 set or show the maximum length limit (in bytes) of a remote
700 target hardware watchpoint.
702 This allows e.g. to use "unlimited" hardware watchpoints with the
703 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
704 watchpoints are slower than real hardware watchpoints but are
705 significantly faster than gdb software watchpoints.
709 ** The register_pretty_printer function in module gdb.printing now takes
710 an optional `replace' argument. If True, the new printer replaces any
713 ** The "maint set python print-stack on|off" command has been
714 deprecated and will be deleted in GDB 7.5.
715 A new command: "set python print-stack none|full|message" has
716 replaced it. Additionally, the default for "print-stack" is
717 now "message", which just prints the error message without
720 ** A prompt substitution hook (prompt_hook) is now available to the
723 ** A new Python module, gdb.prompt has been added to the GDB Python
724 modules library. This module provides functionality for
725 escape sequences in prompts (used by set/show
726 extended-prompt). These escape sequences are replaced by their
729 ** Python commands and convenience-functions located in
730 'data-directory'/python/gdb/command and
731 'data-directory'/python/gdb/function are now automatically loaded
734 ** Blocks now provide four new attributes. global_block and
735 static_block will return the global and static blocks
736 respectively. is_static and is_global are boolean attributes
737 that indicate if the block is one of those two types.
739 ** Symbols now provide the "type" attribute, the type of the symbol.
741 ** The "gdb.breakpoint" function has been deprecated in favor of
744 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
745 of a function. This class is based on the "finish" command
746 available in the CLI.
748 ** Type objects for struct and union types now allow access to
749 the fields using standard Python dictionary (mapping) methods.
750 For example, "some_type['myfield']" now works, as does
753 ** A new event "gdb.new_objfile" has been added, triggered by loading a
756 ** A new function, "deep_items" has been added to the gdb.types
757 module in the GDB Python modules library. This function returns
758 an iterator over the fields of a struct or union type. Unlike
759 the standard Python "iteritems" method, it will recursively traverse
760 any anonymous fields.
764 ** "*stopped" events can report several new "reason"s, such as
767 ** Breakpoint changes are now notified using new async records, like
768 "=breakpoint-modified".
770 ** New command -ada-task-info.
772 * libthread-db-search-path now supports two special values: $sdir and $pdir.
773 $sdir specifies the default system locations of shared libraries.
774 $pdir specifies the directory where the libpthread used by the application
777 GDB no longer looks in $sdir and $pdir after it has searched the directories
778 mentioned in libthread-db-search-path. If you want to search those
779 directories, they must be specified in libthread-db-search-path.
780 The default value of libthread-db-search-path on GNU/Linux and Solaris
781 systems is now "$sdir:$pdir".
783 $pdir is not supported by gdbserver, it is currently ignored.
784 $sdir is supported by gdbserver.
786 * New configure option --with-iconv-bin.
787 When using the internationalization support like the one in the GNU C
788 library, GDB will invoke the "iconv" program to get a list of supported
789 character sets. If this program lives in a non-standard location, one can
790 use this option to specify where to find it.
792 * When natively debugging programs on PowerPC BookE processors running
793 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
794 watchpoints, which specify a mask in addition to an address to watch.
795 The mask specifies that some bits of an address (the bits which are
796 reset in the mask) should be ignored when matching the address accessed
797 by the inferior against the watchpoint address. See the "PowerPC Embedded"
798 section in the user manual for more details.
800 * The new option --once causes GDBserver to stop listening for connections once
801 the first connection is made. The listening port used by GDBserver will
802 become available after that.
804 * New commands "info macros" and "alias" have been added.
806 * New function parameters suffix @entry specifies value of function parameter
807 at the time the function got called. Entry values are available only since
813 "!" is now an alias of the "shell" command.
814 Note that no space is needed between "!" and SHELL COMMAND.
818 watch EXPRESSION mask MASK_VALUE
819 The watch command now supports the mask argument which allows creation
820 of masked watchpoints, if the current architecture supports this feature.
822 info auto-load-scripts [REGEXP]
823 This command was formerly named "maintenance print section-scripts".
824 It is now generally useful and is no longer a maintenance-only command.
826 info macro [-all] [--] MACRO
827 The info macro command has new options `-all' and `--'. The first for
828 printing all definitions of a macro. The second for explicitly specifying
829 the end of arguments and the beginning of the macro name in case the macro
830 name starts with a hyphen.
832 collect[/s] EXPRESSIONS
833 The tracepoint collect command now takes an optional modifier "/s"
834 that directs it to dereference pointer-to-character types and
835 collect the bytes of memory up to a zero byte. The behavior is
836 similar to what you see when you use the regular print command on a
837 string. An optional integer following the "/s" sets a bound on the
838 number of bytes that will be collected.
841 The trace start command now interprets any supplied arguments as a
842 note to be recorded with the trace run, with an effect similar to
843 setting the variable trace-notes.
846 The trace stop command now interprets any arguments as a note to be
847 mentioned along with the tstatus report that the trace was stopped
848 with a command. The effect is similar to setting the variable
851 * Tracepoints can now be enabled and disabled at any time after a trace
852 experiment has been started using the standard "enable" and "disable"
853 commands. It is now possible to start a trace experiment with no enabled
854 tracepoints; GDB will display a warning, but will allow the experiment to
855 begin, assuming that tracepoints will be enabled as needed while the trace
858 * Fast tracepoints on 32-bit x86-architectures can now be placed at
859 locations with 4-byte instructions, when they were previously
860 limited to locations with instructions of 5 bytes or longer.
864 set debug dwarf2-read
865 show debug dwarf2-read
866 Turns on or off display of debugging messages related to reading
867 DWARF debug info. The default is off.
869 set debug symtab-create
870 show debug symtab-create
871 Turns on or off display of debugging messages related to symbol table
872 creation. The default is off.
876 Set the GDB prompt, and allow escape sequences to be inserted to
877 display miscellaneous information (see 'help set extended-prompt'
878 for the list of sequences). This prompt (and any information
879 accessed through the escape sequences) is updated every time the
882 set print entry-values (both|compact|default|if-needed|no|only|preferred)
883 show print entry-values
884 Set printing of frame argument values at function entry. In some cases
885 GDB can determine the value of function argument which was passed by the
886 function caller, even if the value was modified inside the called function.
888 set debug entry-values
889 show debug entry-values
890 Control display of debugging info for determining frame argument values at
891 function entry and virtual tail call frames.
893 set basenames-may-differ
894 show basenames-may-differ
895 Set whether a source file may have multiple base names.
896 (A "base name" is the name of a file with the directory part removed.
897 Example: The base name of "/home/user/hello.c" is "hello.c".)
898 If set, GDB will canonicalize file names (e.g., expand symlinks)
899 before comparing them. Canonicalization is an expensive operation,
900 but it allows the same file be known by more than one base name.
901 If not set (the default), all source files are assumed to have just
902 one base name, and gdb will do file name comparisons more efficiently.
908 Set a user name and notes for the current and any future trace runs.
909 This is useful for long-running and/or disconnected traces, to
910 inform others (or yourself) as to who is running the trace, supply
911 contact information, or otherwise explain what is going on.
914 show trace-stop-notes
915 Set a note attached to the trace run, that is displayed when the
916 trace has been stopped by a tstop command. This is useful for
917 instance as an explanation, if you are stopping a trace run that was
918 started by someone else.
924 Dynamically enable a tracepoint in a started trace experiment.
928 Dynamically disable a tracepoint in a started trace experiment.
932 Set the user and notes of the trace run.
936 Query the current status of a tracepoint.
940 Query the minimum length of instruction at which a fast tracepoint may
943 * Dcache size (number of lines) and line-size are now runtime-configurable
944 via "set dcache line" and "set dcache line-size" commands.
948 Texas Instruments TMS320C6x tic6x-*-*
952 Renesas RL78 rl78-*-elf
954 *** Changes in GDB 7.3.1
956 * The build failure for NetBSD and OpenBSD targets have now been fixed.
958 *** Changes in GDB 7.3
960 * GDB has a new command: "thread find [REGEXP]".
961 It finds the thread id whose name, target id, or thread extra info
962 matches the given regular expression.
964 * The "catch syscall" command now works on mips*-linux* targets.
966 * The -data-disassemble MI command now supports modes 2 and 3 for
967 dumping the instruction opcodes.
969 * New command line options
971 -data-directory DIR Specify DIR as the "data-directory".
972 This is mostly for testing purposes.
974 * The "maint set python auto-load on|off" command has been renamed to
975 "set auto-load-scripts on|off".
977 * GDB has a new command: "set directories".
978 It is like the "dir" command except that it replaces the
979 source path list instead of augmenting it.
981 * GDB now understands thread names.
983 On GNU/Linux, "info threads" will display the thread name as set by
984 prctl or pthread_setname_np.
986 There is also a new command, "thread name", which can be used to
987 assign a name internally for GDB to display.
990 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
991 has been integrated into GDB.
995 ** The function gdb.Write now accepts an optional keyword 'stream'.
996 This keyword, when provided, will direct the output to either
997 stdout, stderr, or GDB's logging output.
999 ** Parameters can now be be sub-classed in Python, and in particular
1000 you may implement the get_set_doc and get_show_doc functions.
1001 This improves how Parameter set/show documentation is processed
1002 and allows for more dynamic content.
1004 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
1005 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
1006 have an is_valid method.
1008 ** Breakpoints can now be sub-classed in Python, and in particular
1009 you may implement a 'stop' function that is executed each time
1010 the inferior reaches that breakpoint.
1012 ** New function gdb.lookup_global_symbol looks up a global symbol.
1014 ** GDB values in Python are now callable if the value represents a
1015 function. For example, if 'some_value' represents a function that
1016 takes two integer parameters and returns a value, you can call
1017 that function like so:
1019 result = some_value (10,20)
1021 ** Module gdb.types has been added.
1022 It contains a collection of utilities for working with gdb.Types objects:
1023 get_basic_type, has_field, make_enum_dict.
1025 ** Module gdb.printing has been added.
1026 It contains utilities for writing and registering pretty-printers.
1027 New classes: PrettyPrinter, SubPrettyPrinter,
1028 RegexpCollectionPrettyPrinter.
1029 New function: register_pretty_printer.
1031 ** New commands "info pretty-printers", "enable pretty-printer" and
1032 "disable pretty-printer" have been added.
1034 ** gdb.parameter("directories") is now available.
1036 ** New function gdb.newest_frame returns the newest frame in the
1039 ** The gdb.InferiorThread class has a new "name" attribute. This
1040 holds the thread's name.
1042 ** Python Support for Inferior events.
1043 Python scripts can add observers to be notified of events
1044 occurring in the process being debugged.
1045 The following events are currently supported:
1046 - gdb.events.cont Continue event.
1047 - gdb.events.exited Inferior exited event.
1048 - gdb.events.stop Signal received, and Breakpoint hit events.
1052 ** GDB now puts template parameters in scope when debugging in an
1053 instantiation. For example, if you have:
1055 template<int X> int func (void) { return X; }
1057 then if you step into func<5>, "print X" will show "5". This
1058 feature requires proper debuginfo support from the compiler; it
1059 was added to GCC 4.5.
1061 ** The motion commands "next", "finish", "until", and "advance" now
1062 work better when exceptions are thrown. In particular, GDB will
1063 no longer lose control of the inferior; instead, the GDB will
1064 stop the inferior at the point at which the exception is caught.
1065 This functionality requires a change in the exception handling
1066 code that was introduced in GCC 4.5.
1068 * GDB now follows GCC's rules on accessing volatile objects when
1069 reading or writing target state during expression evaluation.
1070 One notable difference to prior behavior is that "print x = 0"
1071 no longer generates a read of x; the value of the assignment is
1072 now always taken directly from the value being assigned.
1074 * GDB now has some support for using labels in the program's source in
1075 linespecs. For instance, you can use "advance label" to continue
1076 execution to a label.
1078 * GDB now has support for reading and writing a new .gdb_index
1079 section. This section holds a fast index of DWARF debugging
1080 information and can be used to greatly speed up GDB startup and
1081 operation. See the documentation for `save gdb-index' for details.
1083 * The "watch" command now accepts an optional "-location" argument.
1084 When used, this causes GDB to watch the memory referred to by the
1085 expression. Such a watchpoint is never deleted due to it going out
1088 * GDB now supports thread debugging of core dumps on GNU/Linux.
1090 GDB now activates thread debugging using the libthread_db library
1091 when debugging GNU/Linux core dumps, similarly to when debugging
1092 live processes. As a result, when debugging a core dump file, GDB
1093 is now able to display pthread_t ids of threads. For example, "info
1094 threads" shows the same output as when debugging the process when it
1095 was live. In earlier releases, you'd see something like this:
1098 * 1 LWP 6780 main () at main.c:10
1100 While now you see this:
1103 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
1105 It is also now possible to inspect TLS variables when debugging core
1108 When debugging a core dump generated on a machine other than the one
1109 used to run GDB, you may need to point GDB at the correct
1110 libthread_db library with the "set libthread-db-search-path"
1111 command. See the user manual for more details on this command.
1113 * When natively debugging programs on PowerPC BookE processors running
1114 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
1115 which stop execution of the inferior whenever it executes an instruction
1116 at any address within the specified range. See the "PowerPC Embedded"
1117 section in the user manual for more details.
1119 * New features in the GDB remote stub, GDBserver
1121 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
1122 and i686 LynxOS (version 5.x).
1124 ** GDBserver is now supported on Blackfin Linux.
1126 * New native configurations
1128 ia64 HP-UX ia64-*-hpux*
1132 Analog Devices, Inc. Blackfin Processor bfin-*
1134 * Ada task switching is now supported on sparc-elf targets when
1135 debugging a program using the Ravenscar Profile. For more information,
1136 see the "Tasking Support when using the Ravenscar Profile" section
1137 in the GDB user manual.
1139 * Guile support was removed.
1141 * New features in the GNU simulator
1143 ** The --map-info flag lists all known core mappings.
1145 ** CFI flashes may be simulated via the "cfi" device.
1147 *** Changes in GDB 7.2
1149 * Shared library support for remote targets by default
1151 When GDB is configured for a generic, non-OS specific target, like
1152 for example, --target=arm-eabi or one of the many *-*-elf targets,
1153 GDB now queries remote stubs for loaded shared libraries using the
1154 `qXfer:libraries:read' packet. Previously, shared library support
1155 was always disabled for such configurations.
1159 ** Argument Dependent Lookup (ADL)
1161 In C++ ADL lookup directs function search to the namespaces of its
1162 arguments even if the namespace has not been imported.
1172 Here the compiler will search for `foo' in the namespace of 'b'
1173 and find A::foo. GDB now supports this. This construct is commonly
1174 used in the Standard Template Library for operators.
1176 ** Improved User Defined Operator Support
1178 In addition to member operators, GDB now supports lookup of operators
1179 defined in a namespace and imported with a `using' directive, operators
1180 defined in the global scope, operators imported implicitly from an
1181 anonymous namespace, and the ADL operators mentioned in the previous
1183 GDB now also supports proper overload resolution for all the previously
1184 mentioned flavors of operators.
1186 ** static const class members
1188 Printing of static const class members that are initialized in the
1189 class definition has been fixed.
1191 * Windows Thread Information Block access.
1193 On Windows targets, GDB now supports displaying the Windows Thread
1194 Information Block (TIB) structure. This structure is visible either
1195 by using the new command `info w32 thread-information-block' or, by
1196 dereferencing the new convenience variable named `$_tlb', a
1197 thread-specific pointer to the TIB. This feature is also supported
1198 when remote debugging using GDBserver.
1200 * Static tracepoints
1202 Static tracepoints are calls in the user program into a tracing
1203 library. One such library is a port of the LTTng kernel tracer to
1204 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
1205 When debugging with GDBserver, GDB now supports combining the GDB
1206 tracepoint machinery with such libraries. For example: the user can
1207 use GDB to probe a static tracepoint marker (a call from the user
1208 program into the tracing library) with the new "strace" command (see
1209 "New commands" below). This creates a "static tracepoint" in the
1210 breakpoint list, that can be manipulated with the same feature set
1211 as fast and regular tracepoints. E.g., collect registers, local and
1212 global variables, collect trace state variables, and define
1213 tracepoint conditions. In addition, the user can collect extra
1214 static tracepoint marker specific data, by collecting the new
1215 $_sdata internal variable. When analyzing the trace buffer, you can
1216 inspect $_sdata like any other variable available to GDB. For more
1217 information, see the "Tracepoints" chapter in GDB user manual. New
1218 remote packets have been defined to support static tracepoints, see
1219 the "New remote packets" section below.
1221 * Better reconstruction of tracepoints after disconnected tracing
1223 GDB will attempt to download the original source form of tracepoint
1224 definitions when starting a trace run, and then will upload these
1225 upon reconnection to the target, resulting in a more accurate
1226 reconstruction of the tracepoints that are in use on the target.
1230 You can now exercise direct control over the ways that GDB can
1231 affect your program. For instance, you can disallow the setting of
1232 breakpoints, so that the program can run continuously (assuming
1233 non-stop mode). In addition, the "observer" variable is available
1234 to switch all of the different controls; in observer mode, GDB
1235 cannot affect the target's behavior at all, which is useful for
1236 tasks like diagnosing live systems in the field.
1238 * The new convenience variable $_thread holds the number of the
1241 * New remote packets
1245 Return the address of the Windows Thread Information Block of a given thread.
1249 In response to several of the tracepoint packets, the target may now
1250 also respond with a number of intermediate `qRelocInsn' request
1251 packets before the final result packet, to have GDB handle
1252 relocating an instruction to execute at a different address. This
1253 is particularly useful for stubs that support fast tracepoints. GDB
1254 reports support for this feature in the qSupported packet.
1258 List static tracepoint markers in the target program.
1262 List static tracepoint markers at a given address in the target
1265 qXfer:statictrace:read
1267 Read the static trace data collected (by a `collect $_sdata'
1268 tracepoint action). The remote stub reports support for this packet
1269 to gdb's qSupported query.
1273 Send the current settings of GDB's permission flags.
1277 Send part of the source (textual) form of a tracepoint definition,
1278 which includes location, conditional, and action list.
1280 * The source command now accepts a -s option to force searching for the
1281 script in the source search path even if the script name specifies
1284 * New features in the GDB remote stub, GDBserver
1286 - GDBserver now support tracepoints (including fast tracepoints, and
1287 static tracepoints). The feature is currently supported by the
1288 i386-linux and amd64-linux builds. See the "Tracepoints support
1289 in gdbserver" section in the manual for more information.
1291 GDBserver JIT compiles the tracepoint's conditional agent
1292 expression bytecode into native code whenever possible for low
1293 overhead dynamic tracepoints conditionals. For such tracepoints,
1294 an expression that examines program state is evaluated when the
1295 tracepoint is reached, in order to determine whether to capture
1296 trace data. If the condition is simple and false, processing the
1297 tracepoint finishes very quickly and no data is gathered.
1299 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
1300 for static tracepoints support.
1302 - GDBserver now supports x86_64 Windows 64-bit debugging.
1304 * GDB now sends xmlRegisters= in qSupported packet to indicate that
1305 it understands register description.
1307 * The --batch flag now disables pagination and queries.
1309 * X86 general purpose registers
1311 GDB now supports reading/writing byte, word and double-word x86
1312 general purpose registers directly. This means you can use, say,
1313 $ah or $ax to refer, respectively, to the byte register AH and
1314 16-bit word register AX that are actually portions of the 32-bit
1315 register EAX or 64-bit register RAX.
1317 * The `commands' command now accepts a range of breakpoints to modify.
1318 A plain `commands' following a command that creates multiple
1319 breakpoints affects all the breakpoints set by that command. This
1320 applies to breakpoints set by `rbreak', and also applies when a
1321 single `break' command creates multiple breakpoints (e.g.,
1322 breakpoints on overloaded c++ functions).
1324 * The `rbreak' command now accepts a filename specification as part of
1325 its argument, limiting the functions selected by the regex to those
1326 in the specified file.
1328 * Support for remote debugging Windows and SymbianOS shared libraries
1329 from Unix hosts has been improved. Non Windows GDB builds now can
1330 understand target reported file names that follow MS-DOS based file
1331 system semantics, such as file names that include drive letters and
1332 use the backslash character as directory separator. This makes it
1333 possible to transparently use the "set sysroot" and "set
1334 solib-search-path" on Unix hosts to point as host copies of the
1335 target's shared libraries. See the new command "set
1336 target-file-system-kind" described below, and the "Commands to
1337 specify files" section in the user manual for more information.
1341 eval template, expressions...
1342 Convert the values of one or more expressions under the control
1343 of the string template to a command line, and call it.
1345 set target-file-system-kind unix|dos-based|auto
1346 show target-file-system-kind
1347 Set or show the assumed file system kind for target reported file
1350 save breakpoints <filename>
1351 Save all current breakpoint definitions to a file suitable for use
1352 in a later debugging session. To read the saved breakpoint
1353 definitions, use the `source' command.
1355 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1358 info static-tracepoint-markers
1359 Display information about static tracepoint markers in the target.
1361 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1362 Define a static tracepoint by probing a marker at the given
1363 function, line, address, or marker ID.
1367 Enable and disable observer mode.
1369 set may-write-registers on|off
1370 set may-write-memory on|off
1371 set may-insert-breakpoints on|off
1372 set may-insert-tracepoints on|off
1373 set may-insert-fast-tracepoints on|off
1374 set may-interrupt on|off
1375 Set individual permissions for GDB effects on the target. Note that
1376 some of these settings can have undesirable or surprising
1377 consequences, particularly when changed in the middle of a session.
1378 For instance, disabling the writing of memory can prevent
1379 breakpoints from being inserted, cause single-stepping to fail, or
1380 even crash your program, if you disable after breakpoints have been
1381 inserted. However, GDB should not crash.
1383 set record memory-query on|off
1384 show record memory-query
1385 Control whether to stop the inferior if memory changes caused
1386 by an instruction cannot be recorded.
1391 The disassemble command now supports "start,+length" form of two arguments.
1395 ** GDB now provides a new directory location, called the python directory,
1396 where Python scripts written for GDB can be installed. The location
1397 of that directory is <data-directory>/python, where <data-directory>
1398 is the GDB data directory. For more details, see section `Scripting
1399 GDB using Python' in the manual.
1401 ** The GDB Python API now has access to breakpoints, symbols, symbol
1402 tables, program spaces, inferiors, threads and frame's code blocks.
1403 Additionally, GDB Parameters can now be created from the API, and
1404 manipulated via set/show in the CLI.
1406 ** New functions gdb.target_charset, gdb.target_wide_charset,
1407 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1409 ** New exception gdb.GdbError.
1411 ** Pretty-printers are now also looked up in the current program space.
1413 ** Pretty-printers can now be individually enabled and disabled.
1415 ** GDB now looks for names of Python scripts to auto-load in a
1416 special section named `.debug_gdb_scripts', in addition to looking
1417 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1419 * Tracepoint actions were unified with breakpoint commands. In particular,
1420 there are no longer differences in "info break" output for breakpoints and
1421 tracepoints and the "commands" command can be used for both tracepoints and
1422 regular breakpoints.
1426 ARM Symbian arm*-*-symbianelf*
1428 * D language support.
1429 GDB now supports debugging programs written in the D programming
1432 * GDB now supports the extended ptrace interface for PowerPC which is
1433 available since Linux kernel version 2.6.34. This automatically enables
1434 any hardware breakpoints and additional hardware watchpoints available in
1435 the processor. The old ptrace interface exposes just one hardware
1436 watchpoint and no hardware breakpoints.
1438 * GDB is now able to use the Data Value Compare (DVC) register available on
1439 embedded PowerPC processors to implement in hardware simple watchpoint
1440 conditions of the form:
1442 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1444 This works in native GDB running on Linux kernels with the extended ptrace
1445 interface mentioned above.
1447 *** Changes in GDB 7.1
1451 ** Namespace Support
1453 GDB now supports importing of namespaces in C++. This enables the
1454 user to inspect variables from imported namespaces. Support for
1455 namepace aliasing has also been added. So, if a namespace is
1456 aliased in the current scope (e.g. namepace C=A; ) the user can
1457 print variables using the alias (e.g. (gdb) print C::x).
1461 All known bugs relating to the printing of virtual base class were
1462 fixed. It is now possible to call overloaded static methods using a
1467 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1468 and reinterpret_cast<> are now handled by the C++ expression parser.
1472 Xilinx MicroBlaze microblaze-*-*
1477 Xilinx MicroBlaze microblaze
1480 * Multi-program debugging.
1482 GDB now has support for multi-program (a.k.a. multi-executable or
1483 multi-exec) debugging. This allows for debugging multiple inferiors
1484 simultaneously each running a different program under the same GDB
1485 session. See "Debugging Multiple Inferiors and Programs" in the
1486 manual for more information. This implied some user visible changes
1487 in the multi-inferior support. For example, "info inferiors" now
1488 lists inferiors that are not running yet or that have exited
1489 already. See also "New commands" and "New options" below.
1491 * New tracing features
1493 GDB's tracepoint facility now includes several new features:
1495 ** Trace state variables
1497 GDB tracepoints now include support for trace state variables, which
1498 are variables managed by the target agent during a tracing
1499 experiment. They are useful for tracepoints that trigger each
1500 other, so for instance one tracepoint can count hits in a variable,
1501 and then a second tracepoint has a condition that is true when the
1502 count reaches a particular value. Trace state variables share the
1503 $-syntax of GDB convenience variables, and can appear in both
1504 tracepoint actions and condition expressions. Use the "tvariable"
1505 command to create, and "info tvariables" to view; see "Trace State
1506 Variables" in the manual for more detail.
1510 GDB now includes an option for defining fast tracepoints, which
1511 targets may implement more efficiently, such as by installing a jump
1512 into the target agent rather than a trap instruction. The resulting
1513 speedup can be by two orders of magnitude or more, although the
1514 tradeoff is that some program locations on some target architectures
1515 might not allow fast tracepoint installation, for instance if the
1516 instruction to be replaced is shorter than the jump. To request a
1517 fast tracepoint, use the "ftrace" command, with syntax identical to
1518 the regular trace command.
1520 ** Disconnected tracing
1522 It is now possible to detach GDB from the target while it is running
1523 a trace experiment, then reconnect later to see how the experiment
1524 is going. In addition, a new variable disconnected-tracing lets you
1525 tell the target agent whether to continue running a trace if the
1526 connection is lost unexpectedly.
1530 GDB now has the ability to save the trace buffer into a file, and
1531 then use that file as a target, similarly to you can do with
1532 corefiles. You can select trace frames, print data that was
1533 collected in them, and use tstatus to display the state of the
1534 tracing run at the moment that it was saved. To create a trace
1535 file, use "tsave <filename>", and to use it, do "target tfile
1538 ** Circular trace buffer
1540 You can ask the target agent to handle the trace buffer as a
1541 circular buffer, discarding the oldest trace frames to make room for
1542 newer ones, by setting circular-trace-buffer to on. This feature may
1543 not be available for all target agents.
1548 The disassemble command, when invoked with two arguments, now requires
1549 the arguments to be comma-separated.
1552 The info variables command now displays variable definitions. Files
1553 which only declare a variable are not shown.
1556 The source command is now capable of sourcing Python scripts.
1557 This feature is dependent on the debugger being build with Python
1560 Related to this enhancement is also the introduction of a new command
1561 "set script-extension" (see below).
1563 * New commands (for set/show, see "New options" below)
1565 record save [<FILENAME>]
1566 Save a file (in core file format) containing the process record
1567 execution log for replay debugging at a later time.
1569 record restore <FILENAME>
1570 Restore the process record execution log that was saved at an
1571 earlier time, for replay debugging.
1573 add-inferior [-copies <N>] [-exec <FILENAME>]
1576 clone-inferior [-copies <N>] [ID]
1577 Make a new inferior ready to execute the same program another
1578 inferior has loaded.
1583 maint info program-spaces
1584 List the program spaces loaded into GDB.
1586 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1587 show remote interrupt-sequence
1588 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1589 as the sequence to the remote target in order to interrupt the execution.
1590 Ctrl-C is a default. Some system prefers BREAK which is high level of
1591 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1592 Magic SysRq g. It is BREAK signal and character 'g'.
1594 set remote interrupt-on-connect [on | off]
1595 show remote interrupt-on-connect
1596 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1597 remote target when gdb connects to it. This is needed when you debug
1600 set remotebreak [on | off]
1602 Deprecated. Use "set/show remote interrupt-sequence" instead.
1604 tvariable $NAME [ = EXP ]
1605 Create or modify a trace state variable.
1608 List trace state variables and their values.
1610 delete tvariable $NAME ...
1611 Delete one or more trace state variables.
1614 Evaluate the given expressions without collecting anything into the
1615 trace buffer. (Valid in tracepoint actions only.)
1617 ftrace FN / FILE:LINE / *ADDR
1618 Define a fast tracepoint at the given function, line, or address.
1620 * New expression syntax
1622 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1623 GDB now parses 0b101010 identically with 42.
1627 set follow-exec-mode new|same
1628 show follow-exec-mode
1629 Control whether GDB reuses the same inferior across an exec call or
1630 creates a new one. This is useful to be able to restart the old
1631 executable after the inferior having done an exec call.
1633 set default-collect EXPR, ...
1634 show default-collect
1635 Define a list of expressions to be collected at each tracepoint.
1636 This is a useful way to ensure essential items are not overlooked,
1637 such as registers or a critical global variable.
1639 set disconnected-tracing
1640 show disconnected-tracing
1641 If set to 1, the target is instructed to continue tracing if it
1642 loses its connection to GDB. If 0, the target is to stop tracing
1645 set circular-trace-buffer
1646 show circular-trace-buffer
1647 If set to on, the target is instructed to use a circular trace buffer
1648 and discard the oldest trace frames instead of stopping the trace due
1649 to a full trace buffer. If set to off, the trace stops when the buffer
1650 fills up. Some targets may not support this.
1652 set script-extension off|soft|strict
1653 show script-extension
1654 If set to "off", the debugger does not perform any script language
1655 recognition, and all sourced files are assumed to be GDB scripts.
1656 If set to "soft" (the default), files are sourced according to
1657 filename extension, falling back to GDB scripts if the first
1659 If set to "strict", files are sourced according to filename extension.
1661 set ada trust-PAD-over-XVS on|off
1662 show ada trust-PAD-over-XVS
1663 If off, activate a workaround against a bug in the debugging information
1664 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1665 the GCC sources for more information about the GNAT encoding and
1666 PAD types in particular). It is always safe to set this option to
1667 off, but this introduces a slight performance penalty. The default
1670 * Python API Improvements
1672 ** GDB provides the new class gdb.LazyString. This is useful in
1673 some pretty-printing cases. The new method gdb.Value.lazy_string
1674 provides a simple way to create objects of this type.
1676 ** The fields returned by gdb.Type.fields now have an
1677 `is_base_class' attribute.
1679 ** The new method gdb.Type.range returns the range of an array type.
1681 ** The new method gdb.parse_and_eval can be used to parse and
1682 evaluate an expression.
1684 * New remote packets
1687 Define a trace state variable.
1690 Get the current value of a trace state variable.
1693 Set desired tracing behavior upon disconnection.
1696 Set the trace buffer to be linear or circular.
1699 Get data about the tracepoints currently in use.
1703 Process record now works correctly with hardware watchpoints.
1705 Multiple bug fixes have been made to the mips-irix port, making it
1706 much more reliable. In particular:
1707 - Debugging threaded applications is now possible again. Previously,
1708 GDB would hang while starting the program, or while waiting for
1709 the program to stop at a breakpoint.
1710 - Attaching to a running process no longer hangs.
1711 - An error occurring while loading a core file has been fixed.
1712 - Changing the value of the PC register now works again. This fixes
1713 problems observed when using the "jump" command, or when calling
1714 a function from GDB, or even when assigning a new value to $pc.
1715 - With the "finish" and "return" commands, the return value for functions
1716 returning a small array is now correctly printed.
1717 - It is now possible to break on shared library code which gets executed
1718 during a shared library init phase (code executed while executing
1719 their .init section). Previously, the breakpoint would have no effect.
1720 - GDB is now able to backtrace through the signal handler for
1721 non-threaded programs.
1723 PIE (Position Independent Executable) programs debugging is now supported.
1724 This includes debugging execution of PIC (Position Independent Code) shared
1725 libraries although for that, it should be possible to run such libraries as an
1728 *** Changes in GDB 7.0
1730 * GDB now has an interface for JIT compilation. Applications that
1731 dynamically generate code can create symbol files in memory and register
1732 them with GDB. For users, the feature should work transparently, and
1733 for JIT developers, the interface is documented in the GDB manual in the
1734 "JIT Compilation Interface" chapter.
1736 * Tracepoints may now be conditional. The syntax is as for
1737 breakpoints; either an "if" clause appended to the "trace" command,
1738 or the "condition" command is available. GDB sends the condition to
1739 the target for evaluation using the same bytecode format as is used
1740 for tracepoint actions.
1742 * The disassemble command now supports: an optional /r modifier, print the
1743 raw instructions in hex as well as in symbolic form, and an optional /m
1744 modifier to print mixed source+assembly.
1746 * Process record and replay
1748 In a architecture environment that supports ``process record and
1749 replay'', ``process record and replay'' target can record a log of
1750 the process execution, and replay it with both forward and reverse
1753 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1754 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1755 set execution-direction {forward|reverse}, for targets that support
1758 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1759 feature is available with a native GDB running on kernel version
1762 * GDB now has support for multi-byte and wide character sets on the
1763 target. Strings whose character type is wchar_t, char16_t, or
1764 char32_t are now correctly printed. GDB supports wide- and unicode-
1765 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1766 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1767 `printf'. This feature requires iconv to work properly; if your
1768 system does not have a working iconv, GDB can use GNU libiconv. See
1769 the installation instructions for more information.
1771 * GDB now supports automatic retrieval of shared library files from
1772 remote targets. To use this feature, specify a system root that begins
1773 with the `remote:' prefix, either via the `set sysroot' command or via
1774 the `--with-sysroot' configure-time option.
1776 * "info sharedlibrary" now takes an optional regex of libraries to show,
1777 and it now reports if a shared library has no debugging information.
1779 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1780 now complete on file names.
1782 * When completing in expressions, gdb will attempt to limit
1783 completions to allowable structure or union fields, where appropriate.
1784 For instance, consider:
1786 # struct example { int f1; double f2; };
1787 # struct example variable;
1790 If the user types TAB at the end of this command line, the available
1791 completions will be "f1" and "f2".
1793 * Inlined functions are now supported. They show up in backtraces, and
1794 the "step", "next", and "finish" commands handle them automatically.
1796 * GDB now supports the token-splicing (##) and stringification (#)
1797 operators when expanding macros. It also supports variable-arity
1800 * GDB now supports inspecting extra signal information, exported by
1801 the new $_siginfo convenience variable. The feature is currently
1802 implemented on linux ARM, i386 and amd64.
1804 * GDB can now display the VFP floating point registers and NEON vector
1805 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1806 can provide these registers (requires Linux 2.6.30 or later). Remote
1807 and simulator targets may also provide them.
1809 * New remote packets
1812 Search memory for a sequence of bytes.
1815 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1816 operation over reliable transport links. Use of this packet is
1817 controlled by the `set remote noack-packet' command.
1820 Kill the process with the specified process ID. Use this in preference
1821 to `k' when multiprocess protocol extensions are supported.
1824 Obtains additional operating system information
1828 Read or write additional signal information.
1830 * Removed remote protocol undocumented extension
1832 An undocumented extension to the remote protocol's `S' stop reply
1833 packet that permited the stub to pass a process id was removed.
1834 Remote servers should use the `T' stop reply packet instead.
1836 * GDB now supports multiple function calling conventions according to the
1837 DWARF-2 DW_AT_calling_convention function attribute.
1839 * The SH target utilizes the aforementioned change to distinguish between gcc
1840 and Renesas calling convention. It also adds the new CLI commands
1841 `set/show sh calling-convention'.
1843 * GDB can now read compressed debug sections, as produced by GNU gold
1844 with the --compress-debug-sections=zlib flag.
1846 * 64-bit core files are now supported on AIX.
1848 * Thread switching is now supported on Tru64.
1850 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1851 which will be allocated using malloc later in program execution.
1853 * The qXfer:libraries:read remote procotol packet now allows passing a
1854 list of section offsets.
1856 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1857 conditions handling signals delivered during attach or thread creation
1858 have also been fixed.
1860 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1861 From the user's standpoint, all unqualified instances of True and False
1862 are treated as the standard definitions, regardless of context.
1864 * GDB now parses C++ symbol and type names more flexibly. For
1867 template<typename T> class C { };
1870 GDB will now correctly handle all of:
1872 ptype C<char const *>
1873 ptype C<char const*>
1874 ptype C<const char *>
1875 ptype C<const char*>
1877 * New features in the GDB remote stub, gdbserver
1879 - The "--wrapper" command-line argument tells gdbserver to use a
1880 wrapper program to launch programs for debugging.
1882 - On PowerPC and S/390 targets, it is now possible to use a single
1883 gdbserver executable to debug both 32-bit and 64-bit programs.
1884 (This requires gdbserver itself to be built as a 64-bit executable.)
1886 - gdbserver uses the new noack protocol mode for TCP connections to
1887 reduce communications latency, if also supported and enabled in GDB.
1889 - Support for the sparc64-linux-gnu target is now included in
1892 - The amd64-linux build of gdbserver now supports debugging both
1893 32-bit and 64-bit programs.
1895 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1896 now support hardware watchpoints, and will use them automatically
1901 GDB now has support for scripting using Python. Whether this is
1902 available is determined at configure time.
1904 New GDB commands can now be written in Python.
1906 * Ada tasking support
1908 Ada tasks can now be inspected in GDB. The following commands have
1912 Print the list of Ada tasks.
1914 Print detailed information about task number N.
1916 Print the task number of the current task.
1918 Switch the context of debugging to task number N.
1920 * Support for user-defined prefixed commands. The "define" command can
1921 add new commands to existing prefixes, e.g. "target".
1923 * Multi-inferior, multi-process debugging.
1925 GDB now has generalized support for multi-inferior debugging. See
1926 "Debugging Multiple Inferiors" in the manual for more information.
1927 Although availability still depends on target support, the command
1928 set is more uniform now. The GNU/Linux specific multi-forks support
1929 has been migrated to this new framework. This implied some user
1930 visible changes; see "New commands" and also "Removed commands"
1933 * Target descriptions can now describe the target OS ABI. See the
1934 "Target Description Format" section in the user manual for more
1937 * Target descriptions can now describe "compatible" architectures
1938 to indicate that the target can execute applications for a different
1939 architecture in addition to those for the main target architecture.
1940 See the "Target Description Format" section in the user manual for
1943 * Multi-architecture debugging.
1945 GDB now includes general supports for debugging applications on
1946 hybrid systems that use more than one single processor architecture
1947 at the same time. Each such hybrid architecture still requires
1948 specific support to be added. The only hybrid architecture supported
1949 in this version of GDB is the Cell Broadband Engine.
1951 * GDB now supports integrated debugging of Cell/B.E. applications that
1952 use both the PPU and SPU architectures. To enable support for hybrid
1953 Cell/B.E. debugging, you need to configure GDB to support both the
1954 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1955 --enable-targets configure option.
1957 * Non-stop mode debugging.
1959 For some targets, GDB now supports an optional mode of operation in
1960 which you can examine stopped threads while other threads continue
1961 to execute freely. This is referred to as non-stop mode, with the
1962 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1963 section in the user manual for more information.
1965 To be able to support remote non-stop debugging, a remote stub needs
1966 to implement the non-stop mode remote protocol extensions, as
1967 described in the "Remote Non-Stop" section of the user manual. The
1968 GDB remote stub, gdbserver, has been adjusted to support these
1969 extensions on linux targets.
1971 * New commands (for set/show, see "New options" below)
1973 catch syscall [NAME(S) | NUMBER(S)]
1974 Catch system calls. Arguments, which should be names of system
1975 calls or their numbers, mean catch only those syscalls. Without
1976 arguments, every syscall will be caught. When the inferior issues
1977 any of the specified syscalls, GDB will stop and announce the system
1978 call, both when it is called and when its call returns. This
1979 feature is currently available with a native GDB running on the
1980 Linux Kernel, under the following architectures: x86, x86_64,
1981 PowerPC and PowerPC64.
1983 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1985 Search memory for a sequence of bytes.
1987 maint set python print-stack
1988 maint show python print-stack
1989 Show a stack trace when an error is encountered in a Python script.
1992 Invoke CODE by passing it to the Python interpreter.
1997 These allow macros to be defined, undefined, and listed
2001 Show operating system information about processes.
2004 List the inferiors currently under GDB's control.
2007 Switch focus to inferior number NUM.
2010 Detach from inferior number NUM.
2013 Kill inferior number NUM.
2017 set spu stop-on-load
2018 show spu stop-on-load
2019 Control whether to stop for new SPE threads during Cell/B.E. debugging.
2021 set spu auto-flush-cache
2022 show spu auto-flush-cache
2023 Control whether to automatically flush the software-managed cache
2024 during Cell/B.E. debugging.
2026 set sh calling-convention
2027 show sh calling-convention
2028 Control the calling convention used when calling SH target functions.
2031 show debug timestamp
2032 Control display of timestamps with GDB debugging output.
2034 set disassemble-next-line
2035 show disassemble-next-line
2036 Control display of disassembled source lines or instructions when
2039 set remote noack-packet
2040 show remote noack-packet
2041 Set/show the use of remote protocol QStartNoAckMode packet. See above
2042 under "New remote packets."
2044 set remote query-attached-packet
2045 show remote query-attached-packet
2046 Control use of remote protocol `qAttached' (query-attached) packet.
2048 set remote read-siginfo-object
2049 show remote read-siginfo-object
2050 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
2053 set remote write-siginfo-object
2054 show remote write-siginfo-object
2055 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
2058 set remote reverse-continue
2059 show remote reverse-continue
2060 Control use of remote protocol 'bc' (reverse-continue) packet.
2062 set remote reverse-step
2063 show remote reverse-step
2064 Control use of remote protocol 'bs' (reverse-step) packet.
2066 set displaced-stepping
2067 show displaced-stepping
2068 Control displaced stepping mode. Displaced stepping is a way to
2069 single-step over breakpoints without removing them from the debuggee.
2070 Also known as "out-of-line single-stepping".
2073 show debug displaced
2074 Control display of debugging info for displaced stepping.
2076 maint set internal-error
2077 maint show internal-error
2078 Control what GDB does when an internal error is detected.
2080 maint set internal-warning
2081 maint show internal-warning
2082 Control what GDB does when an internal warning is detected.
2087 Use a wrapper program to launch programs for debugging.
2089 set multiple-symbols (all|ask|cancel)
2090 show multiple-symbols
2091 The value of this variable can be changed to adjust the debugger behavior
2092 when an expression or a breakpoint location contains an ambiguous symbol
2093 name (an overloaded function name, for instance).
2095 set breakpoint always-inserted
2096 show breakpoint always-inserted
2097 Keep breakpoints always inserted in the target, as opposed to inserting
2098 them when resuming the target, and removing them when the target stops.
2099 This option can improve debugger performance on slow remote targets.
2101 set arm fallback-mode (arm|thumb|auto)
2102 show arm fallback-mode
2103 set arm force-mode (arm|thumb|auto)
2105 These commands control how ARM GDB determines whether instructions
2106 are ARM or Thumb. The default for both settings is auto, which uses
2107 the current CPSR value for instructions without symbols; previous
2108 versions of GDB behaved as if "set arm fallback-mode arm".
2110 set disable-randomization
2111 show disable-randomization
2112 Standalone programs run with the virtual address space randomization enabled
2113 by default on some platforms. This option keeps the addresses stable across
2114 multiple debugging sessions.
2118 Control whether other threads are stopped or not when some thread hits
2123 Requests that asynchronous execution is enabled in the target, if available.
2124 In this case, it's possible to resume target in the background, and interact
2125 with GDB while the target is running. "show target-async" displays the
2126 current state of asynchronous execution of the target.
2128 set target-wide-charset
2129 show target-wide-charset
2130 The target-wide-charset is the name of the character set that GDB
2131 uses when printing characters whose type is wchar_t.
2133 set tcp auto-retry (on|off)
2135 set tcp connect-timeout
2136 show tcp connect-timeout
2137 These commands allow GDB to retry failed TCP connections to a remote stub
2138 with a specified timeout period; this is useful if the stub is launched
2139 in parallel with GDB but may not be ready to accept connections immediately.
2141 set libthread-db-search-path
2142 show libthread-db-search-path
2143 Control list of directories which GDB will search for appropriate
2146 set schedule-multiple (on|off)
2147 show schedule-multiple
2148 Allow GDB to resume all threads of all processes or only threads of
2149 the current process.
2153 Use more aggressive caching for accesses to the stack. This improves
2154 performance of remote debugging (particularly backtraces) without
2155 affecting correctness.
2157 set interactive-mode (on|off|auto)
2158 show interactive-mode
2159 Control whether GDB runs in interactive mode (on) or not (off).
2160 When in interactive mode, GDB waits for the user to answer all
2161 queries. Otherwise, GDB does not wait and assumes the default
2162 answer. When set to auto (the default), GDB determines which
2163 mode to use based on the stdin settings.
2168 For program forks, this is replaced by the new more generic `info
2169 inferiors' command. To list checkpoints, you can still use the
2170 `info checkpoints' command, which was an alias for the `info forks'
2174 Replaced by the new `inferior' command. To switch between
2175 checkpoints, you can still use the `restart' command, which was an
2176 alias for the `fork' command.
2179 This is removed, since some targets don't have a notion of
2180 processes. To switch between processes, you can still use the
2181 `inferior' command using GDB's own inferior number.
2184 For program forks, this is replaced by the new more generic `kill
2185 inferior' command. To delete a checkpoint, you can still use the
2186 `delete checkpoint' command, which was an alias for the `delete
2190 For program forks, this is replaced by the new more generic `detach
2191 inferior' command. To detach a checkpoint, you can still use the
2192 `detach checkpoint' command, which was an alias for the `detach
2195 * New native configurations
2197 x86/x86_64 Darwin i[34567]86-*-darwin*
2199 x86_64 MinGW x86_64-*-mingw*
2203 Lattice Mico32 lm32-*
2204 x86 DICOS i[34567]86-*-dicos*
2205 x86_64 DICOS x86_64-*-dicos*
2208 * The GDB remote stub, gdbserver, now supports x86 Windows CE
2209 (mingw32ce) debugging.
2215 These commands were actually not implemented on any target.
2217 *** Changes in GDB 6.8
2219 * New native configurations
2221 NetBSD/hppa hppa*-*netbsd*
2222 Xtensa GNU/Linux xtensa*-*-linux*
2226 NetBSD/hppa hppa*-*-netbsd*
2227 Xtensa GNU/Lunux xtensa*-*-linux*
2229 * Change in command line behavior -- corefiles vs. process ids.
2231 When the '-p NUMBER' or '--pid NUMBER' options are used, and
2232 attaching to process NUMBER fails, GDB no longer attempts to open a
2233 core file named NUMBER. Attaching to a program using the -c option
2234 is no longer supported. Instead, use the '-p' or '--pid' options.
2236 * GDB can now be built as a native debugger for debugging Windows x86
2237 (mingw32) Portable Executable (PE) programs.
2239 * Pending breakpoints no longer change their number when their address
2242 * GDB now supports breakpoints with multiple locations,
2243 including breakpoints on C++ constructors, inside C++ templates,
2244 and in inlined functions.
2246 * GDB's ability to debug optimized code has been improved. GDB more
2247 accurately identifies function bodies and lexical blocks that occupy
2248 more than one contiguous range of addresses.
2250 * Target descriptions can now describe registers for PowerPC.
2252 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
2253 registers on PowerPC targets.
2255 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
2256 targets even when the libthread_db library is not available.
2258 * The GDB remote stub, gdbserver, now supports the new file transfer
2259 commands (remote put, remote get, and remote delete).
2261 * The GDB remote stub, gdbserver, now supports run and attach in
2262 extended-remote mode.
2264 * hppa*64*-*-hpux11* target broken
2265 The debugger is unable to start a program and fails with the following
2266 error: "Error trying to get information about dynamic linker".
2267 The gdb-6.7 release is also affected.
2269 * GDB now supports the --enable-targets= configure option to allow
2270 building a single GDB executable that supports multiple remote
2271 target architectures.
2273 * GDB now supports debugging C and C++ programs which use the
2274 Decimal Floating Point extension. In addition, the PowerPC target
2275 now has a set of pseudo-registers to inspect decimal float values
2276 stored in two consecutive float registers.
2278 * The -break-insert MI command can optionally create pending
2281 * Improved support for debugging Ada
2282 Many improvements to the Ada language support have been made. These
2284 - Better support for Ada2005 interface types
2285 - Improved handling of arrays and slices in general
2286 - Better support for Taft-amendment types
2287 - The '{type} ADDRESS' expression is now allowed on the left hand-side
2289 - Improved command completion in Ada
2292 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
2297 set print frame-arguments (all|scalars|none)
2298 show print frame-arguments
2299 The value of this variable can be changed to control which argument
2300 values should be printed by the debugger when displaying a frame.
2305 Transfer files to and from a remote target, and delete remote files.
2312 Transfer files to and from a remote target, and delete remote files.
2314 * New remote packets
2321 Open, close, read, write, and delete files on the remote system.
2324 Attach to an existing process on the remote system, in extended-remote
2328 Run a new process on the remote system, in extended-remote mode.
2330 *** Changes in GDB 6.7
2332 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
2333 bfd, libiberty and opcodes, as revealed by static analysis donated by
2334 Coverity, Inc. (http://scan.coverity.com).
2336 * When looking up multiply-defined global symbols, GDB will now prefer the
2337 symbol definition in the current shared library if it was built using the
2338 -Bsymbolic linker option.
2340 * When the Text User Interface (TUI) is not configured, GDB will now
2341 recognize the -tui command-line option and print a message that the TUI
2344 * The GDB remote stub, gdbserver, now has lower overhead for high
2345 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
2347 * GDB for MIPS targets now autodetects whether a remote target provides
2348 32-bit or 64-bit register values.
2350 * Support for C++ member pointers has been improved.
2352 * GDB now understands XML target descriptions, which specify the
2353 target's overall architecture. GDB can read a description from
2354 a local file or over the remote serial protocol.
2356 * Vectors of single-byte data use a new integer type which is not
2357 automatically displayed as character or string data.
2359 * The /s format now works with the print command. It displays
2360 arrays of single-byte integers and pointers to single-byte integers
2363 * Target descriptions can now describe target-specific registers,
2364 for architectures which have implemented the support (currently
2365 only ARM, M68K, and MIPS).
2367 * GDB and the GDB remote stub, gdbserver, now support the XScale
2370 * The GDB remote stub, gdbserver, has been updated to support
2371 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2372 has been rewritten to use the standard GDB remote protocol.
2374 * GDB can now step into C++ functions which are called through thunks.
2376 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2378 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2379 layout. It also supports a TextSeg= and DataSeg= response when only
2380 segment base addresses (rather than offsets) are available.
2382 * The /i format now outputs any trailing branch delay slot instructions
2383 immediately following the last instruction within the count specified.
2385 * The GDB remote protocol "T" stop reply packet now supports a
2386 "library" response. Combined with the new "qXfer:libraries:read"
2387 packet, this response allows GDB to debug shared libraries on targets
2388 where the operating system manages the list of loaded libraries (e.g.
2389 Windows and SymbianOS).
2391 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2392 (DLLs) on Windows and Windows CE targets.
2394 * GDB now supports a faster verification that a .debug file matches its binary
2395 according to its build-id signature, if the signature is present.
2401 Enable or disable hardware flow control (RTS/CTS) on the serial port
2402 when debugging using remote targets.
2404 set mem inaccessible-by-default
2405 show mem inaccessible-by-default
2406 If the target supplies a memory map, for instance via the remote
2407 protocol's "qXfer:memory-map:read" packet, setting this variable
2408 prevents GDB from accessing memory outside the memory map. This
2409 is useful for targets with memory mapped registers or which react
2410 badly to accesses of unmapped address space.
2412 set breakpoint auto-hw
2413 show breakpoint auto-hw
2414 If the target supplies a memory map, for instance via the remote
2415 protocol's "qXfer:memory-map:read" packet, setting this variable
2416 lets GDB use hardware breakpoints automatically for memory regions
2417 where it can not use software breakpoints. This covers both the
2418 "break" command and internal breakpoints used for other commands
2419 including "next" and "finish".
2422 catch exception unhandled
2423 Stop the program execution when Ada exceptions are raised.
2426 Stop the program execution when an Ada assertion failed.
2430 Set an alternate system root for target files. This is a more
2431 general version of "set solib-absolute-prefix", which is now
2432 an alias to "set sysroot".
2435 Provide extended SPU facility status information. This set of
2436 commands is available only when debugging the Cell/B.E. SPU
2439 * New native configurations
2441 OpenBSD/sh sh*-*openbsd*
2444 unset tdesc filename
2446 Use the specified local file as an XML target description, and do
2447 not query the target for its built-in description.
2451 OpenBSD/sh sh*-*-openbsd*
2452 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2453 Toshiba Media Processor mep-elf
2455 * New remote packets
2458 Ignore the specified signals; pass them directly to the debugged program
2459 without stopping other threads or reporting them to GDB.
2461 qXfer:features:read:
2462 Read an XML target description from the target, which describes its
2467 Read or write contents of an spufs file on the target system. These
2468 packets are available only on the Cell/B.E. SPU architecture.
2470 qXfer:libraries:read:
2471 Report the loaded shared libraries. Combined with new "T" packet
2472 response, this packet allows GDB to debug shared libraries on
2473 targets where the operating system manages the list of loaded
2474 libraries (e.g. Windows and SymbianOS).
2478 Support for these obsolete configurations has been removed.
2486 i[34567]86-*-lynxos*
2487 i[34567]86-*-netware*
2488 i[34567]86-*-sco3.2v5*
2489 i[34567]86-*-sco3.2v4*
2491 i[34567]86-*-sysv4.2*
2494 i[34567]86-*-unixware2*
2495 i[34567]86-*-unixware*
2504 * Other removed features
2511 Various m68k-only ROM monitors.
2518 Various Renesas ROM monitors and debugging interfaces for SH and
2523 Support for a Macraigor serial interface to on-chip debugging.
2524 GDB does not directly support the newer parallel or USB
2529 A debug information format. The predecessor to DWARF 2 and
2530 DWARF 3, which are still supported.
2532 Support for the HP aCC compiler on HP-UX/PA-RISC
2534 SOM-encapsulated symbolic debugging information, automatic
2535 invocation of pxdb, and the aCC custom C++ ABI. This does not
2536 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2537 with aCC can still be debugged on an assembly level.
2539 MIPS ".pdr" sections
2541 A MIPS-specific format used to describe stack frame layout
2542 in debugging information.
2546 GDB could work with an older version of Guile to debug
2547 the interpreter and Scheme programs running in it.
2549 set mips stack-arg-size
2550 set mips saved-gpreg-size
2552 Use "set mips abi" to control parameter passing for MIPS.
2554 *** Changes in GDB 6.6
2559 Cell Broadband Engine SPU spu-elf
2561 * GDB can now be configured as a cross-debugger targeting native Windows
2562 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2563 running on a Windows system over TCP/IP to debug Windows programs.
2565 * The GDB remote stub, gdbserver, has been updated to support Windows and
2566 Cygwin debugging. Both single-threaded and multi-threaded programs are
2569 * The "set trust-readonly-sections" command works again. This command was
2570 broken in GDB 6.3, 6.4, and 6.5.
2572 * The "load" command now supports writing to flash memory, if the remote
2573 stub provides the required support.
2575 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2576 longer requires symbolic debug information (e.g. DWARF-2).
2581 unset substitute-path
2582 show substitute-path
2583 Manage a list of substitution rules that GDB uses to rewrite the name
2584 of the directories where the sources are located. This can be useful
2585 for instance when the sources were moved to a different location
2586 between compilation and debugging.
2590 Print each CLI command as it is executed. Each command is prefixed with
2591 a number of `+' symbols representing the nesting depth.
2592 The source command now has a `-v' option to enable the same feature.
2596 The ARM Demon monitor support (RDP protocol, "target rdp").
2598 Kernel Object Display, an embedded debugging feature which only worked with
2599 an obsolete version of Cisco IOS.
2601 The 'set download-write-size' and 'show download-write-size' commands.
2603 * New remote packets
2606 Tell a stub about GDB client features, and request remote target features.
2607 The first feature implemented is PacketSize, which allows the target to
2608 specify the size of packets it can handle - to minimize the number of
2609 packets required and improve performance when connected to a remote
2613 Fetch an OS auxilliary vector from the remote stub. This packet is a
2614 more efficient replacement for qPart:auxv:read.
2616 qXfer:memory-map:read:
2617 Fetch a memory map from the remote stub, including information about
2618 RAM, ROM, and flash memory devices.
2623 Erase and program a flash memory device.
2625 * Removed remote packets
2628 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2629 used it, and only gdbserver implemented it.
2631 *** Changes in GDB 6.5
2635 Renesas M32C/M16C m32c-elf
2637 Morpho Technologies ms1 ms1-elf
2641 init-if-undefined Initialize a convenience variable, but
2642 only if it doesn't already have a value.
2644 The following commands are presently only implemented for native GNU/Linux:
2646 checkpoint Save a snapshot of the program state.
2648 restart <n> Return the program state to a
2649 previously saved state.
2651 info checkpoints List currently saved checkpoints.
2653 delete-checkpoint <n> Delete a previously saved checkpoint.
2655 set|show detach-on-fork Tell gdb whether to detach from a newly
2656 forked process, or to keep debugging it.
2658 info forks List forks of the user program that
2659 are available to be debugged.
2661 fork <n> Switch to debugging one of several
2662 forks of the user program that are
2663 available to be debugged.
2665 delete-fork <n> Delete a fork from the list of forks
2666 that are available to be debugged (and
2667 kill the forked process).
2669 detach-fork <n> Delete a fork from the list of forks
2670 that are available to be debugged (and
2671 allow the process to continue).
2675 Morpho Technologies ms2 ms1-elf
2677 * Improved Windows host support
2679 GDB now builds as a cross debugger hosted on i686-mingw32, including
2680 native console support, and remote communications using either
2681 network sockets or serial ports.
2683 * Improved Modula-2 language support
2685 GDB can now print most types in the Modula-2 syntax. This includes:
2686 basic types, set types, record types, enumerated types, range types,
2687 pointer types and ARRAY types. Procedure var parameters are correctly
2688 printed and hexadecimal addresses and character constants are also
2689 written in the Modula-2 syntax. Best results can be obtained by using
2690 GNU Modula-2 together with the -gdwarf-2 command line option.
2694 The ARM rdi-share module.
2696 The Netware NLM debug server.
2698 *** Changes in GDB 6.4
2700 * New native configurations
2702 OpenBSD/arm arm*-*-openbsd*
2703 OpenBSD/mips64 mips64-*-openbsd*
2707 Morpho Technologies ms1 ms1-elf
2709 * New command line options
2711 --batch-silent As for --batch, but totally silent.
2712 --return-child-result The debugger will exist with the same value
2713 the child (debugged) program exited with.
2714 --eval-command COMMAND, -ex COMMAND
2715 Execute a single GDB CLI command. This may be
2716 specified multiple times and in conjunction
2717 with the --command (-x) option.
2719 * Deprecated commands removed
2721 The following commands, that were deprecated in 2000, have been
2725 set|show arm disassembly-flavor set|show arm disassembler
2726 othernames set arm disassembler
2727 set|show remotedebug set|show debug remote
2728 set|show archdebug set|show debug arch
2729 set|show eventdebug set|show debug event
2732 * New BSD user-level threads support
2734 It is now possible to debug programs using the user-level threads
2735 library on OpenBSD and FreeBSD. Currently supported (target)
2738 FreeBSD/amd64 x86_64-*-freebsd*
2739 FreeBSD/i386 i386-*-freebsd*
2740 OpenBSD/i386 i386-*-openbsd*
2742 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2743 are not yet supported.
2745 * New support for Matsushita MN10300 w/sim added
2746 (Work in progress). mn10300-elf.
2748 * REMOVED configurations and files
2750 VxWorks and the XDR protocol *-*-vxworks
2751 Motorola MCORE mcore-*-*
2752 National Semiconductor NS32000 ns32k-*-*
2754 * New "set print array-indexes" command
2756 After turning this setting "on", GDB prints the index of each element
2757 when displaying arrays. The default is "off" to preserve the previous
2760 * VAX floating point support
2762 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2764 * User-defined command support
2766 In addition to using $arg0..$arg9 for argument passing, it is now possible
2767 to use $argc to determine now many arguments have been passed. See the
2768 section on user-defined commands in the user manual for more information.
2770 *** Changes in GDB 6.3:
2772 * New command line option
2774 GDB now accepts -l followed by a number to set the timeout for remote
2777 * GDB works with GCC -feliminate-dwarf2-dups
2779 GDB now supports a more compact representation of DWARF-2 debug
2780 information using DW_FORM_ref_addr references. These are produced
2781 by GCC with the option -feliminate-dwarf2-dups and also by some
2782 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2783 to use -feliminate-dwarf2-dups.
2785 * Internationalization
2787 When supported by the host system, GDB will be built with
2788 internationalization (libintl). The task of marking up the sources is
2789 continued, we're looking forward to our first translation.
2793 Initial support for debugging programs compiled with the GNAT
2794 implementation of the Ada programming language has been integrated
2795 into GDB. In this release, support is limited to expression evaluation.
2797 * New native configurations
2799 GNU/Linux/m32r m32r-*-linux-gnu
2803 GDB's remote protocol now includes support for the 'p' packet. This
2804 packet is used to fetch individual registers from a remote inferior.
2806 * END-OF-LIFE registers[] compatibility module
2808 GDB's internal register infrastructure has been completely rewritten.
2809 The new infrastructure making possible the implementation of key new
2810 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2813 GDB 6.3 will be the last release to include the the registers[]
2814 compatibility module that allowed out-of-date configurations to
2815 continue to work. This change directly impacts the following
2825 powerpc bdm protocol
2827 Unless there is activity to revive these configurations, they will be
2828 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2830 * OBSOLETE configurations and files
2832 Configurations that have been declared obsolete in this release have
2833 been commented out. Unless there is activity to revive these
2834 configurations, the next release of GDB will have their sources
2835 permanently REMOVED.
2844 *** Changes in GDB 6.2.1:
2846 * MIPS `break main; run' gave an heuristic-fence-post warning
2848 When attempting to run even a simple program, a warning about
2849 heuristic-fence-post being hit would be reported. This problem has
2852 * MIPS IRIX 'long double' crashed GDB
2854 When examining a long double variable, GDB would get a segmentation
2855 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2856 IRIX long double values).
2860 A bug in the VAX stack code was causing problems with the "next"
2861 command. This problem has been fixed.
2863 *** Changes in GDB 6.2:
2865 * Fix for ``many threads''
2867 On GNU/Linux systems that use the NPTL threads library, a program
2868 rapidly creating and deleting threads would confuse GDB leading to the
2871 ptrace: No such process.
2872 thread_db_get_info: cannot get thread info: generic error
2874 This problem has been fixed.
2876 * "-async" and "-noasync" options removed.
2878 Support for the broken "-noasync" option has been removed (it caused
2881 * New ``start'' command.
2883 This command runs the program until the begining of the main procedure.
2885 * New BSD Kernel Data Access Library (libkvm) interface
2887 Using ``target kvm'' it is now possible to debug kernel core dumps and
2888 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2889 platforms. Currently supported (native-only) configurations are:
2891 FreeBSD/amd64 x86_64-*-freebsd*
2892 FreeBSD/i386 i?86-*-freebsd*
2893 NetBSD/i386 i?86-*-netbsd*
2894 NetBSD/m68k m68*-*-netbsd*
2895 NetBSD/sparc sparc-*-netbsd*
2896 OpenBSD/amd64 x86_64-*-openbsd*
2897 OpenBSD/i386 i?86-*-openbsd*
2898 OpenBSD/m68k m68*-openbsd*
2899 OpenBSD/sparc sparc-*-openbsd*
2901 * Signal trampoline code overhauled
2903 Many generic problems with GDB's signal handling code have been fixed.
2904 These include: backtraces through non-contiguous stacks; recognition
2905 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2906 call; backtrace through a signal trampoline; step into and out of
2907 signal handlers; and single-stepping in the signal trampoline.
2909 Please note that kernel bugs are a limiting factor here. These
2910 features have been shown to work on an s390 GNU/Linux system that
2911 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2913 * Cygwin support for DWARF 2 added.
2915 * New native configurations
2917 GNU/Linux/hppa hppa*-*-linux*
2918 OpenBSD/hppa hppa*-*-openbsd*
2919 OpenBSD/m68k m68*-*-openbsd*
2920 OpenBSD/m88k m88*-*-openbsd*
2921 OpenBSD/powerpc powerpc-*-openbsd*
2922 NetBSD/vax vax-*-netbsd*
2923 OpenBSD/vax vax-*-openbsd*
2925 * END-OF-LIFE frame compatibility module
2927 GDB's internal frame infrastructure has been completely rewritten.
2928 The new infrastructure making it possible to support key new features
2929 including DWARF 2 Call Frame Information. To aid in the task of
2930 migrating old configurations to this new infrastructure, a
2931 compatibility module, that allowed old configurations to continue to
2932 work, was also included.
2934 GDB 6.2 will be the last release to include this frame compatibility
2935 module. This change directly impacts the following configurations:
2945 Unless there is activity to revive these configurations, they will be
2946 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2948 * REMOVED configurations and files
2950 Sun 3, running SunOS 3 m68*-*-sunos3*
2951 Sun 3, running SunOS 4 m68*-*-sunos4*
2952 Sun 2, running SunOS 3 m68000-*-sunos3*
2953 Sun 2, running SunOS 4 m68000-*-sunos4*
2954 Motorola 680x0 running LynxOS m68*-*-lynxos*
2955 AT&T 3b1/Unix pc m68*-att-*
2956 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2957 decstation mips-dec-* mips-little-*
2958 riscos mips-*-riscos* mips-*-sysv*
2959 sonymips mips-sony-*
2960 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2962 *** Changes in GDB 6.1.1:
2964 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2966 The TUI (Text-mode User Interface) is now built as part of a default
2967 GDB configuration. It is enabled by either selecting the TUI with the
2968 command line option "-i=tui" or by running the separate "gdbtui"
2969 program. For more information on the TUI, see the manual "Debugging
2972 * Pending breakpoint support (also included in GDB 6.1)
2974 Support has been added to allow you to specify breakpoints in shared
2975 libraries that have not yet been loaded. If a breakpoint location
2976 cannot be found, and the "breakpoint pending" option is set to auto,
2977 GDB queries you if you wish to make the breakpoint pending on a future
2978 shared-library load. If and when GDB resolves the breakpoint symbol,
2979 the pending breakpoint is removed as one or more regular breakpoints
2982 Pending breakpoints are very useful for GCJ Java debugging.
2984 * Fixed ISO-C build problems
2986 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2987 non ISO-C code that stopped them being built using a more strict ISO-C
2988 compiler (e.g., IBM's C compiler).
2990 * Fixed build problem on IRIX 5
2992 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2993 wasn't able to compile compile on an IRIX 5 system.
2995 * Added execute permission to gdb/gdbserver/configure
2997 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2998 permission. This bug would cause configure to fail on a number of
2999 systems (Solaris, IRIX). Ref: server/519.
3001 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
3003 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
3004 has been updated to use constant array sizes.
3006 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
3008 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
3009 its generated DWARF Call Frame Info. This encoding was causing GDB to
3010 panic, that panic has been fixed. Ref: gdb/1628.
3012 * Fixed a problem when examining parameters in shared library code.
3014 When examining parameters in optimized shared library code generated
3015 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
3016 not available''. GDB now correctly displays the variable's value.
3018 *** Changes in GDB 6.1:
3020 * Removed --with-mmalloc
3022 Support for the mmalloc memory manager has been removed, as it
3023 conflicted with the internal gdb byte cache.
3025 * Changes in AMD64 configurations
3027 The AMD64 target now includes the %cs and %ss registers. As a result
3028 the AMD64 remote protocol has changed; this affects the floating-point
3029 and SSE registers. If you rely on those registers for your debugging,
3030 you should upgrade gdbserver on the remote side.
3032 * Revised SPARC target
3034 The SPARC target has been completely revised, incorporating the
3035 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
3036 support for LynxOS and SunOS 4 has been dropped. Calling functions
3037 from within GDB on operating systems with a non-executable stack
3038 (Solaris, OpenBSD) now works.
3042 GDB has a new C++ demangler which does a better job on the mangled
3043 names generated by current versions of g++. It also runs faster, so
3044 with this and other changes gdb should now start faster on large C++
3047 * DWARF 2 Location Expressions
3049 GDB support for location expressions has been extended to support function
3050 arguments and frame bases. Older versions of GDB could crash when they
3053 * C++ nested types and namespaces
3055 GDB's support for nested types and namespaces in C++ has been
3056 improved, especially if you use the DWARF 2 debugging format. (This
3057 is the default for recent versions of GCC on most platforms.)
3058 Specifically, if you have a class "Inner" defined within a class or
3059 namespace "Outer", then GDB realizes that the class's name is
3060 "Outer::Inner", not simply "Inner". This should greatly reduce the
3061 frequency of complaints about not finding RTTI symbols. In addition,
3062 if you are stopped at inside of a function defined within a namespace,
3063 GDB modifies its name lookup accordingly.
3065 * New native configurations
3067 NetBSD/amd64 x86_64-*-netbsd*
3068 OpenBSD/amd64 x86_64-*-openbsd*
3069 OpenBSD/alpha alpha*-*-openbsd*
3070 OpenBSD/sparc sparc-*-openbsd*
3071 OpenBSD/sparc64 sparc64-*-openbsd*
3073 * New debugging protocols
3075 M32R with SDI protocol m32r-*-elf*
3077 * "set prompt-escape-char" command deleted.
3079 The command "set prompt-escape-char" has been deleted. This command,
3080 and its very obscure effet on GDB's prompt, was never documented,
3081 tested, nor mentioned in the NEWS file.
3083 * OBSOLETE configurations and files
3085 Configurations that have been declared obsolete in this release have
3086 been commented out. Unless there is activity to revive these
3087 configurations, the next release of GDB will have their sources
3088 permanently REMOVED.
3090 Sun 3, running SunOS 3 m68*-*-sunos3*
3091 Sun 3, running SunOS 4 m68*-*-sunos4*
3092 Sun 2, running SunOS 3 m68000-*-sunos3*
3093 Sun 2, running SunOS 4 m68000-*-sunos4*
3094 Motorola 680x0 running LynxOS m68*-*-lynxos*
3095 AT&T 3b1/Unix pc m68*-att-*
3096 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
3097 decstation mips-dec-* mips-little-*
3098 riscos mips-*-riscos* mips-*-sysv*
3099 sonymips mips-sony-*
3100 sysv mips*-*-sysv4* (IRIX 5/6 not included)
3102 * REMOVED configurations and files
3104 SGI Irix-4.x mips-sgi-irix4 or iris4
3105 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3106 Z8000 simulator z8k-zilog-none or z8ksim
3107 Matsushita MN10200 w/simulator mn10200-*-*
3108 H8/500 simulator h8500-hitachi-hms or h8500hms
3109 HP/PA running BSD hppa*-*-bsd*
3110 HP/PA running OSF/1 hppa*-*-osf*
3111 HP/PA Pro target hppa*-*-pro*
3112 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3113 386BSD i[3456]86-*-bsd*
3114 Sequent family i[3456]86-sequent-sysv4*
3115 i[3456]86-sequent-sysv*
3116 i[3456]86-sequent-bsd*
3117 SPARC running LynxOS sparc-*-lynxos*
3118 SPARC running SunOS 4 sparc-*-sunos4*
3119 Tsqware Sparclet sparclet-*-*
3120 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3122 *** Changes in GDB 6.0:
3126 Support for debugging the Objective-C programming language has been
3127 integrated into GDB.
3129 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
3131 DWARF 2's Call Frame Information makes available compiler generated
3132 information that more exactly describes the program's run-time stack.
3133 By using this information, GDB is able to provide more robust stack
3136 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
3137 have been updated to use a new backtrace mechanism which includes
3138 DWARF 2 CFI support.
3142 GDB's remote protocol has been extended to include support for hosted
3143 file I/O (where the remote target uses GDB's file system). See GDB's
3144 remote protocol documentation for details.
3146 * All targets using the new architecture framework.
3148 All of GDB's targets have been updated to use the new internal
3149 architecture framework. The way is now open for future GDB releases
3150 to include cross-architecture native debugging support (i386 on amd64,
3153 * GNU/Linux's Thread Local Storage (TLS)
3155 GDB now includes support for for the GNU/Linux implementation of
3156 per-thread variables.
3158 * GNU/Linux's Native POSIX Thread Library (NPTL)
3160 GDB's thread code has been updated to work with either the new
3161 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
3163 * Separate debug info.
3165 GDB, in conjunction with BINUTILS, now supports a mechanism for
3166 automatically loading debug information from a separate file. Instead
3167 of shipping full debug and non-debug versions of system libraries,
3168 system integrators can now instead ship just the stripped libraries
3169 and optional debug files.
3171 * DWARF 2 Location Expressions
3173 DWARF 2 Location Expressions allow the compiler to more completely
3174 describe the location of variables (even in optimized code) to the
3177 GDB now includes preliminary support for location expressions (support
3178 for DW_OP_piece is still missing).
3182 A number of long standing bugs that caused GDB to die while starting a
3183 Java application have been fixed. GDB's Java support is now
3184 considered "useable".
3186 * GNU/Linux support for fork, vfork, and exec.
3188 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
3189 commands are now implemented for GNU/Linux. They require a 2.5.x or later
3192 * GDB supports logging output to a file
3194 There are two new commands, "set logging" and "show logging", which can be
3195 used to capture GDB's output to a file.
3197 * The meaning of "detach" has changed for gdbserver
3199 The "detach" command will now resume the application, as documented. To
3200 disconnect from gdbserver and leave it stopped, use the new "disconnect"
3203 * d10v, m68hc11 `regs' command deprecated
3205 The `info registers' command has been updated so that it displays the
3206 registers using a format identical to the old `regs' command.
3210 A new command, "maint set profile on/off", has been added. This command can
3211 be used to enable or disable profiling while running GDB, to profile a
3212 session or a set of commands. In addition there is a new configure switch,
3213 "--enable-profiling", which will cause GDB to be compiled with profiling
3214 data, for more informative profiling results.
3216 * Default MI syntax changed to "mi2".
3218 The default MI (machine interface) syntax, enabled by the command line
3219 option "-i=mi", has been changed to "mi2". The previous MI syntax,
3220 "mi1", can be enabled by specifying the option "-i=mi1".
3222 Support for the original "mi0" syntax (included in GDB 5.0) has been
3225 Fix for gdb/192: removed extraneous space when displaying frame level.
3226 Fix for gdb/672: update changelist is now output in mi list format.
3227 Fix for gdb/702: a -var-assign that updates the value now shows up
3228 in a subsequent -var-update.
3230 * New native configurations.
3232 FreeBSD/amd64 x86_64-*-freebsd*
3234 * Multi-arched targets.
3236 HP/PA HPUX11 hppa*-*-hpux*
3237 Renesas M32R/D w/simulator m32r-*-elf*
3239 * OBSOLETE configurations and files
3241 Configurations that have been declared obsolete in this release have
3242 been commented out. Unless there is activity to revive these
3243 configurations, the next release of GDB will have their sources
3244 permanently REMOVED.
3246 Z8000 simulator z8k-zilog-none or z8ksim
3247 Matsushita MN10200 w/simulator mn10200-*-*
3248 H8/500 simulator h8500-hitachi-hms or h8500hms
3249 HP/PA running BSD hppa*-*-bsd*
3250 HP/PA running OSF/1 hppa*-*-osf*
3251 HP/PA Pro target hppa*-*-pro*
3252 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
3253 Sequent family i[3456]86-sequent-sysv4*
3254 i[3456]86-sequent-sysv*
3255 i[3456]86-sequent-bsd*
3256 Tsqware Sparclet sparclet-*-*
3257 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3259 * REMOVED configurations and files
3262 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3263 IBM AIX PS/2 i[3456]86-*-aix
3264 i386 running Mach 3.0 i[3456]86-*-mach3*
3265 i386 running Mach i[3456]86-*-mach*
3266 i386 running OSF/1 i[3456]86-*osf1mk*
3267 HP/Apollo 68k Family m68*-apollo*-sysv*,
3269 m68*-hp-bsd*, m68*-hp-hpux*
3270 Argonaut Risc Chip (ARC) arc-*-*
3271 Mitsubishi D30V d30v-*-*
3272 Fujitsu FR30 fr30-*-elf*
3273 OS/9000 i[34]86-*-os9k
3274 I960 with MON960 i960-*-coff
3276 * MIPS $fp behavior changed
3278 The convenience variable $fp, for the MIPS, now consistently returns
3279 the address of the current frame's base. Previously, depending on the
3280 context, $fp could refer to either $sp or the current frame's base
3281 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
3282 The GNU Source-Level Debugger''.
3284 *** Changes in GDB 5.3:
3286 * GNU/Linux shared library multi-threaded performance improved.
3288 When debugging a multi-threaded application on GNU/Linux, GDB now uses
3289 `/proc', in preference to `ptrace' for memory reads. This may result
3290 in an improvement in the start-up time of multi-threaded, shared
3291 library applications when run under GDB. One GDB user writes: ``loads
3292 shared libs like mad''.
3294 * ``gdbserver'' now supports multi-threaded applications on some targets
3296 Support for debugging multi-threaded applications which use
3297 the GNU/Linux LinuxThreads package has been added for
3298 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
3299 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
3301 * GDB now supports C/C++ preprocessor macros.
3303 GDB now expands preprocessor macro invocations in C/C++ expressions,
3304 and provides various commands for showing macro definitions and how
3307 The new command `macro expand EXPRESSION' expands any macro
3308 invocations in expression, and shows the result.
3310 The new command `show macro MACRO-NAME' shows the definition of the
3311 macro named MACRO-NAME, and where it was defined.
3313 Most compilers don't include information about macros in the debugging
3314 information by default. In GCC 3.1, for example, you need to compile
3315 your program with the options `-gdwarf-2 -g3'. If the macro
3316 information is present in the executable, GDB will read it.
3318 * Multi-arched targets.
3320 DEC Alpha (partial) alpha*-*-*
3321 DEC VAX (partial) vax-*-*
3323 National Semiconductor NS32000 (partial) ns32k-*-*
3324 Motorola 68000 (partial) m68k-*-*
3325 Motorola MCORE mcore-*-*
3329 Fujitsu FRV architecture added by Red Hat frv*-*-*
3332 * New native configurations
3334 Alpha NetBSD alpha*-*-netbsd*
3335 SH NetBSD sh*-*-netbsdelf*
3336 MIPS NetBSD mips*-*-netbsd*
3337 UltraSPARC NetBSD sparc64-*-netbsd*
3339 * OBSOLETE configurations and files
3341 Configurations that have been declared obsolete in this release have
3342 been commented out. Unless there is activity to revive these
3343 configurations, the next release of GDB will have their sources
3344 permanently REMOVED.
3346 Mitsubishi D30V d30v-*-*
3347 OS/9000 i[34]86-*-os9k
3348 IBM AIX PS/2 i[3456]86-*-aix
3349 Fujitsu FR30 fr30-*-elf*
3350 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3351 Argonaut Risc Chip (ARC) arc-*-*
3352 i386 running Mach 3.0 i[3456]86-*-mach3*
3353 i386 running Mach i[3456]86-*-mach*
3354 i386 running OSF/1 i[3456]86-*osf1mk*
3355 HP/Apollo 68k Family m68*-apollo*-sysv*,
3357 m68*-hp-bsd*, m68*-hp-hpux*
3358 I960 with MON960 i960-*-coff
3360 * OBSOLETE languages
3362 CHILL, a Pascal like language used by telecommunications companies.
3364 * REMOVED configurations and files
3366 AMD 29k family via UDI a29k-amd-udi, udi29k
3367 A29K VxWorks a29k-*-vxworks
3368 AMD 29000 embedded, using EBMON a29k-none-none
3369 AMD 29000 embedded with COFF a29k-none-coff
3370 AMD 29000 embedded with a.out a29k-none-aout
3372 testsuite/gdb.hp/gdb.threads-hp/ directory
3374 * New command "set max-user-call-depth <nnn>"
3376 This command allows the user to limit the call depth of user-defined
3377 commands. The default is 1024.
3379 * Changes in FreeBSD/i386 native debugging.
3381 Support for the "generate-core-file" has been added.
3383 * New commands "dump", "append", and "restore".
3385 These commands allow data to be copied from target memory
3386 to a bfd-format or binary file (dump and append), and back
3387 from a file into memory (restore).
3389 * Improved "next/step" support on multi-processor Alpha Tru64.
3391 The previous single-step mechanism could cause unpredictable problems,
3392 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3393 of a software single-step mechanism prevents this.
3395 *** Changes in GDB 5.2.1:
3403 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3404 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3405 Fix, by Joel Brobecker imported from mainline.
3407 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3408 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3409 Fix, by Fred Fish, imported from mainline.
3411 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3412 Surprisingly enough, it works now.
3413 By Michal Ludvig, imported from mainline.
3415 i386 hardware watchpoint support:
3416 avoid misses on second run for some targets.
3417 By Pierre Muller, imported from mainline.
3419 *** Changes in GDB 5.2:
3421 * New command "set trust-readonly-sections on[off]".
3423 This command is a hint that tells gdb that read-only sections
3424 really are read-only (ie. that their contents will not change).
3425 In this mode, gdb will go to the object file rather than the
3426 target to read memory from read-only sections (such as ".text").
3427 This can be a significant performance improvement on some
3428 (notably embedded) targets.
3430 * New command "generate-core-file" (or "gcore").
3432 This new gdb command allows the user to drop a core file of the child
3433 process state at any time. So far it's been implemented only for
3434 GNU/Linux and Solaris, but should be relatively easily ported to other
3435 hosts. Argument is core file name (defaults to core.<pid>).
3437 * New command line option
3439 GDB now accepts --pid or -p followed by a process id.
3441 * Change in command line behavior -- corefiles vs. process ids.
3443 There is a subtle behavior in the way in which GDB handles
3444 command line arguments. The first non-flag argument is always
3445 a program to debug, but the second non-flag argument may either
3446 be a corefile or a process id. Previously, GDB would attempt to
3447 open the second argument as a corefile, and if that failed, would
3448 issue a superfluous error message and then attempt to attach it as
3449 a process. Now, if the second argument begins with a non-digit,
3450 it will be treated as a corefile. If it begins with a digit,
3451 GDB will attempt to attach it as a process, and if no such process
3452 is found, will then attempt to open it as a corefile.
3454 * Changes in ARM configurations.
3456 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3457 configuration is fully multi-arch.
3459 * New native configurations
3461 ARM NetBSD arm*-*-netbsd*
3462 x86 OpenBSD i[3456]86-*-openbsd*
3463 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3464 Sparc64 running FreeBSD sparc64-*-freebsd*
3468 Sanyo XStormy16 xstormy16-elf
3470 * OBSOLETE configurations and files
3472 Configurations that have been declared obsolete in this release have
3473 been commented out. Unless there is activity to revive these
3474 configurations, the next release of GDB will have their sources
3475 permanently REMOVED.
3477 AMD 29k family via UDI a29k-amd-udi, udi29k
3478 A29K VxWorks a29k-*-vxworks
3479 AMD 29000 embedded, using EBMON a29k-none-none
3480 AMD 29000 embedded with COFF a29k-none-coff
3481 AMD 29000 embedded with a.out a29k-none-aout
3483 testsuite/gdb.hp/gdb.threads-hp/ directory
3485 * REMOVED configurations and files
3487 TI TMS320C80 tic80-*-*
3489 PowerPC Solaris powerpcle-*-solaris*
3490 PowerPC Windows NT powerpcle-*-cygwin32
3491 PowerPC Netware powerpc-*-netware*
3492 Harris/CXUX m88k m88*-harris-cxux*
3493 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3494 ns32k-utek-sysv* ns32k-utek-*
3495 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3496 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3497 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3498 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3499 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3501 * Changes to command line processing
3503 The new `--args' feature can be used to specify command-line arguments
3504 for the inferior from gdb's command line.
3506 * Changes to key bindings
3508 There is a new `operate-and-get-next' function bound to `C-o'.
3510 *** Changes in GDB 5.1.1
3512 Fix compile problem on DJGPP.
3514 Fix a problem with floating-point registers on the i386 being
3517 Fix to stop GDB crashing on .debug_str debug info.
3519 Numerous documentation fixes.
3521 Numerous testsuite fixes.
3523 *** Changes in GDB 5.1:
3525 * New native configurations
3527 Alpha FreeBSD alpha*-*-freebsd*
3528 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3529 MIPS GNU/Linux mips*-*-linux*
3530 MIPS SGI Irix 6.x mips*-sgi-irix6*
3531 ia64 AIX ia64-*-aix*
3532 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3536 Motorola 68HC11 and 68HC12 m68hc11-elf
3538 UltraSparc running GNU/Linux sparc64-*-linux*
3540 * OBSOLETE configurations and files
3542 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3543 Harris/CXUX m88k m88*-harris-cxux*
3544 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3545 ns32k-utek-sysv* ns32k-utek-*
3546 TI TMS320C80 tic80-*-*
3548 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3549 PowerPC Solaris powerpcle-*-solaris*
3550 PowerPC Windows NT powerpcle-*-cygwin32
3551 PowerPC Netware powerpc-*-netware*
3552 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3553 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3554 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3555 Apple Macintosh (MPW) host N/A
3557 stuff.c (Program to stuff files into a specially prepared space in kdb)
3558 kdb-start.c (Main loop for the standalone kernel debugger)
3560 Configurations that have been declared obsolete in this release have
3561 been commented out. Unless there is activity to revive these
3562 configurations, the next release of GDB will have their sources
3563 permanently REMOVED.
3565 * REMOVED configurations and files
3567 Altos 3068 m68*-altos-*
3568 Convex c1-*-*, c2-*-*
3570 ARM RISCix arm-*-* (as host)
3574 * GDB has been converted to ISO C.
3576 GDB's source code has been converted to ISO C. In particular, the
3577 sources are fully protoized, and rely on standard headers being
3582 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3584 * The MI enabled by default.
3586 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3587 revised and enabled by default. Packages which use GDB as a debugging
3588 engine behind a UI or another front end are encouraged to switch to
3589 using the GDB/MI interface, instead of the old annotations interface
3590 which is now deprecated.
3592 * Support for debugging Pascal programs.
3594 GDB now includes support for debugging Pascal programs. The following
3595 main features are supported:
3597 - Pascal-specific data types such as sets;
3599 - automatic recognition of Pascal sources based on file-name
3602 - Pascal-style display of data types, variables, and functions;
3604 - a Pascal expression parser.
3606 However, some important features are not yet supported.
3608 - Pascal string operations are not supported at all;
3610 - there are some problems with boolean types;
3612 - Pascal type hexadecimal constants are not supported
3613 because they conflict with the internal variables format;
3615 - support for Pascal objects and classes is not full yet;
3617 - unlike Pascal, GDB is case-sensitive for symbol names.
3619 * Changes in completion.
3621 Commands such as `shell', `run' and `set args', which pass arguments
3622 to inferior programs, now complete on file names, similar to what
3623 users expect at the shell prompt.
3625 Commands which accept locations, such as `disassemble', `print',
3626 `breakpoint', `until', etc. now complete on filenames as well as
3627 program symbols. Thus, if you type "break foob TAB", and the source
3628 files linked into the programs include `foobar.c', that file name will
3629 be one of the candidates for completion. However, file names are not
3630 considered for completion after you typed a colon that delimits a file
3631 name from a name of a function in that file, as in "break foo.c:bar".
3633 `set demangle-style' completes on available demangling styles.
3635 * New platform-independent commands:
3637 It is now possible to define a post-hook for a command as well as a
3638 hook that runs before the command. For more details, see the
3639 documentation of `hookpost' in the GDB manual.
3641 * Changes in GNU/Linux native debugging.
3643 Support for debugging multi-threaded programs has been completely
3644 revised for all platforms except m68k and sparc. You can now debug as
3645 many threads as your system allows you to have.
3647 Attach/detach is supported for multi-threaded programs.
3649 Support for SSE registers was added for x86. This doesn't work for
3650 multi-threaded programs though.
3652 * Changes in MIPS configurations.
3654 Multi-arch support is enabled for all MIPS configurations.
3656 GDB can now be built as native debugger on SGI Irix 6.x systems for
3657 debugging n32 executables. (Debugging 64-bit executables is not yet
3660 * Unified support for hardware watchpoints in all x86 configurations.
3662 Most (if not all) native x86 configurations support hardware-assisted
3663 breakpoints and watchpoints in a unified manner. This support
3664 implements debug register sharing between watchpoints, which allows to
3665 put a virtually infinite number of watchpoints on the same address,
3666 and also supports watching regions up to 16 bytes with several debug
3669 The new maintenance command `maintenance show-debug-regs' toggles
3670 debugging print-outs in functions that insert, remove, and test
3671 watchpoints and hardware breakpoints.
3673 * Changes in the DJGPP native configuration.
3675 New command ``info dos sysinfo'' displays assorted information about
3676 the CPU, OS, memory, and DPMI server.
3678 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3679 display information about segment descriptors stored in GDT, LDT, and
3682 New commands ``info dos pde'' and ``info dos pte'' display entries
3683 from Page Directory and Page Tables (for now works with CWSDPMI only).
3684 New command ``info dos address-pte'' displays the Page Table entry for
3685 a given linear address.
3687 GDB can now pass command lines longer than 126 characters to the
3688 program being debugged (requires an update to the libdbg.a library
3689 which is part of the DJGPP development kit).
3691 DWARF2 debug info is now supported.
3693 It is now possible to `step' and `next' through calls to `longjmp'.
3695 * Changes in documentation.
3697 All GDB documentation was converted to GFDL, the GNU Free
3698 Documentation License.
3700 Tracepoints-related commands are now fully documented in the GDB
3703 TUI, the Text-mode User Interface, is now documented in the manual.
3705 Tracepoints-related commands are now fully documented in the GDB
3708 The "GDB Internals" manual now has an index. It also includes
3709 documentation of `ui_out' functions, GDB coding standards, x86
3710 hardware watchpoints, and memory region attributes.
3712 * GDB's version number moved to ``version.in''
3714 The Makefile variable VERSION has been replaced by the file
3715 ``version.in''. People creating GDB distributions should update the
3716 contents of this file.
3720 GUD support is now a standard part of the EMACS distribution.
3722 *** Changes in GDB 5.0:
3724 * Improved support for debugging FP programs on x86 targets
3726 Unified and much-improved support for debugging floating-point
3727 programs on all x86 targets. In particular, ``info float'' now
3728 displays the FP registers in the same format on all x86 targets, with
3729 greater level of detail.
3731 * Improvements and bugfixes in hardware-assisted watchpoints
3733 It is now possible to watch array elements, struct members, and
3734 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3735 on x86 targets no longer erroneously trigger when the address is
3738 * Improvements in the native DJGPP version of GDB
3740 The distribution now includes all the scripts and auxiliary files
3741 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3742 machines ``out of the box''.
3744 The DJGPP version can now debug programs that use signals. It is
3745 possible to catch signals that happened in the debuggee, deliver
3746 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3747 would kill the program being debugged.) Programs that hook hardware
3748 interrupts (keyboard, timer, etc.) can also be debugged.
3750 It is now possible to debug DJGPP programs that redirect their
3751 standard handles or switch them to raw (as opposed to cooked) mode, or
3752 even close them. The command ``run < foo > bar'' works as expected,
3753 and ``info terminal'' reports useful information about the debuggee's
3754 terminal, including raw/cooked mode, redirection, etc.
3756 The DJGPP version now uses termios functions for console I/O, which
3757 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3760 DOS-style file names with drive letters are now fully supported by
3763 It is now possible to debug DJGPP programs that switch their working
3764 directory. It is also possible to rerun the debuggee any number of
3765 times without restarting GDB; thus, you can use the same setup,
3766 breakpoints, etc. for many debugging sessions.
3768 * New native configurations
3770 ARM GNU/Linux arm*-*-linux*
3771 PowerPC GNU/Linux powerpc-*-linux*
3775 Motorola MCore mcore-*-*
3776 x86 VxWorks i[3456]86-*-vxworks*
3777 PowerPC VxWorks powerpc-*-vxworks*
3778 TI TMS320C80 tic80-*-*
3780 * OBSOLETE configurations
3782 Altos 3068 m68*-altos-*
3783 Convex c1-*-*, c2-*-*
3785 ARM RISCix arm-*-* (as host)
3788 Configurations that have been declared obsolete will be commented out,
3789 but the code will be left in place. If there is no activity to revive
3790 these configurations before the next release of GDB, the sources will
3791 be permanently REMOVED.
3793 * Gould support removed
3795 Support for the Gould PowerNode and NP1 has been removed.
3797 * New features for SVR4
3799 On SVR4 native platforms (such as Solaris), if you attach to a process
3800 without first loading a symbol file, GDB will now attempt to locate and
3801 load symbols from the running process's executable file.
3803 * Many C++ enhancements
3805 C++ support has been greatly improved. Overload resolution now works properly
3806 in almost all cases. RTTI support is on the way.
3808 * Remote targets can connect to a sub-program
3810 A popen(3) style serial-device has been added. This device starts a
3811 sub-process (such as a stand-alone simulator) and then communicates
3812 with that. The sub-program to run is specified using the syntax
3813 ``|<program> <args>'' vis:
3815 (gdb) set remotedebug 1
3816 (gdb) target extended-remote |mn10300-elf-sim program-args
3818 * MIPS 64 remote protocol
3820 A long standing bug in the mips64 remote protocol where by GDB
3821 expected certain 32 bit registers (ex SR) to be transfered as 32
3822 instead of 64 bits has been fixed.
3824 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3825 added to provide backward compatibility with older versions of GDB.
3827 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3829 The command ``set remotebinarydownload'' command has been replaced by
3830 ``set remote X-packet''. Other commands in ``set remote'' family
3831 include ``set remote P-packet''.
3833 * Breakpoint commands accept ranges.
3835 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3836 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3837 ``tracepoint passcount'' also accepts a range of tracepoints.
3839 * ``apropos'' command added.
3841 The ``apropos'' command searches through command names and
3842 documentation strings, printing out matches, making it much easier to
3843 try to find a command that does what you are looking for.
3847 A new machine oriented interface (MI) has been added to GDB. This
3848 interface is designed for debug environments running GDB as a separate
3849 process. This is part of the long term libGDB project. See the
3850 "GDB/MI" chapter of the GDB manual for further information. It can be
3851 enabled by configuring with:
3853 .../configure --enable-gdbmi
3855 *** Changes in GDB-4.18:
3857 * New native configurations
3859 HP-UX 10.20 hppa*-*-hpux10.20
3860 HP-UX 11.x hppa*-*-hpux11.0*
3861 M68K GNU/Linux m68*-*-linux*
3865 Fujitsu FR30 fr30-*-elf*
3866 Intel StrongARM strongarm-*-*
3867 Mitsubishi D30V d30v-*-*
3869 * OBSOLETE configurations
3871 Gould PowerNode, NP1 np1-*-*, pn-*-*
3873 Configurations that have been declared obsolete will be commented out,
3874 but the code will be left in place. If there is no activity to revive
3875 these configurations before the next release of GDB, the sources will
3876 be permanently REMOVED.
3880 As a compatibility experiment, GDB's source files buildsym.h and
3881 buildsym.c have been converted to pure standard C, no longer
3882 containing any K&R compatibility code. We believe that all systems in
3883 use today either come with a standard C compiler, or have a GCC port
3884 available. If this is not true, please report the affected
3885 configuration to bug-gdb@gnu.org immediately. See the README file for
3886 information about getting a standard C compiler if you don't have one
3891 GDB now uses readline 2.2.
3893 * set extension-language
3895 You can now control the mapping between filename extensions and source
3896 languages by using the `set extension-language' command. For instance,
3897 you can ask GDB to treat .c files as C++ by saying
3898 set extension-language .c c++
3899 The command `info extensions' lists all of the recognized extensions
3900 and their associated languages.
3902 * Setting processor type for PowerPC and RS/6000
3904 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3905 you can use the `set processor' command to specify what variant of the
3906 PowerPC family you are debugging. The command
3910 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3911 following PowerPC and RS6000 variants:
3913 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3914 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3916 403GC IBM PowerPC 403GC
3917 505 Motorola PowerPC 505
3918 860 Motorola PowerPC 860 or 850
3919 601 Motorola PowerPC 601
3920 602 Motorola PowerPC 602
3921 603 Motorola/IBM PowerPC 603 or 603e
3922 604 Motorola PowerPC 604 or 604e
3923 750 Motorola/IBM PowerPC 750 or 750
3925 At the moment, this command just tells GDB what to name the
3926 special-purpose processor registers. Since almost all the affected
3927 registers are inaccessible to user-level programs, this command is
3928 only useful for remote debugging in its present form.
3932 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3933 more extensive support for HP-UX. Added features include shared
3934 library support, kernel threads and hardware watchpoints for 11.00,
3935 support for HP's ANSI C and C++ compilers, and a compatibility mode
3936 for xdb and dbx commands.
3940 HP's donation includes the new concept of catchpoints, which is a
3941 generalization of the old catch command. On HP-UX, it is now possible
3942 to catch exec, fork, and vfork, as well as library loading.
3944 This means that the existing catch command has changed; its first
3945 argument now specifies the type of catch to be set up. See the
3946 output of "help catch" for a list of catchpoint types.
3948 * Debugging across forks
3950 On HP-UX, you can choose which process to debug when a fork() happens
3955 HP has donated a curses-based terminal user interface (TUI). To get
3956 it, build with --enable-tui. Although this can be enabled for any
3957 configuration, at present it only works for native HP debugging.
3959 * GDB remote protocol additions
3961 A new protocol packet 'X' that writes binary data is now available.
3962 Default behavior is to try 'X', then drop back to 'M' if the stub
3963 fails to respond. The settable variable `remotebinarydownload'
3964 allows explicit control over the use of 'X'.
3966 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3967 full 64-bit address. The command
3969 set remoteaddresssize 32
3971 can be used to revert to the old behaviour. For existing remote stubs
3972 the change should not be noticed, as the additional address information
3975 In order to assist in debugging stubs, you may use the maintenance
3976 command `packet' to send any text string to the stub. For instance,
3978 maint packet heythere
3980 sends the packet "$heythere#<checksum>". Note that it is very easy to
3981 disrupt a debugging session by sending the wrong packet at the wrong
3984 The compare-sections command allows you to compare section data on the
3985 target to what is in the executable file without uploading or
3986 downloading, by comparing CRC checksums.
3988 * Tracing can collect general expressions
3990 You may now collect general expressions at tracepoints. This requires
3991 further additions to the target-side stub; see tracepoint.c and
3992 doc/agentexpr.texi for further details.
3994 * mask-address variable for Mips
3996 For Mips targets, you may control the zeroing of the upper 32 bits of
3997 a 64-bit address by entering `set mask-address on'. This is mainly
3998 of interest to users of embedded R4xxx and R5xxx processors.
4000 * Higher serial baud rates
4002 GDB's serial code now allows you to specify baud rates 57600, 115200,
4003 230400, and 460800 baud. (Note that your host system may not be able
4004 to achieve all of these rates.)
4008 The i960 configuration now includes an initial implementation of a
4009 builtin simulator, contributed by Jim Wilson.
4012 *** Changes in GDB-4.17:
4014 * New native configurations
4016 Alpha GNU/Linux alpha*-*-linux*
4017 Unixware 2.x i[3456]86-unixware2*
4018 Irix 6.x mips*-sgi-irix6*
4019 PowerPC GNU/Linux powerpc-*-linux*
4020 PowerPC Solaris powerpcle-*-solaris*
4021 Sparc GNU/Linux sparc-*-linux*
4022 Motorola sysV68 R3V7.1 m68k-motorola-sysv
4026 Argonaut Risc Chip (ARC) arc-*-*
4027 Hitachi H8/300S h8300*-*-*
4028 Matsushita MN10200 w/simulator mn10200-*-*
4029 Matsushita MN10300 w/simulator mn10300-*-*
4030 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
4031 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
4032 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
4033 Mitsubishi D10V w/simulator d10v-*-*
4034 Mitsubishi M32R/D w/simulator m32r-*-elf*
4035 Tsqware Sparclet sparclet-*-*
4036 NEC V850 w/simulator v850-*-*
4038 * New debugging protocols
4040 ARM with RDI protocol arm*-*-*
4041 M68K with dBUG monitor m68*-*-{aout,coff,elf}
4042 DDB and LSI variants of PMON protocol mips*-*-*
4043 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
4044 PowerPC with SDS protocol powerpc{,le}-*-eabi
4045 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
4049 All configurations can now understand and use the DWARF 2 debugging
4050 format. The choice is automatic, if the symbol file contains DWARF 2
4055 GDB now includes basic Java language support. This support is
4056 only useful with Java compilers that produce native machine code.
4058 * solib-absolute-prefix and solib-search-path
4060 For SunOS and SVR4 shared libraries, you may now set the prefix for
4061 loading absolute shared library symbol files, and the search path for
4062 locating non-absolute shared library symbol files.
4064 * Live range splitting
4066 GDB can now effectively debug code for which GCC has performed live
4067 range splitting as part of its optimization. See gdb/doc/LRS for
4068 more details on the expected format of the stabs information.
4072 GDB's support for the GNU Hurd, including thread debugging, has been
4073 updated to work with current versions of the Hurd.
4077 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
4078 instruction set. ARM GDB automatically detects when Thumb
4079 instructions are in use, and adjusts disassembly and backtracing
4084 GDB's MIPS target configurations now handle the MIP16 16-bit
4089 GDB now includes support for overlays; if an executable has been
4090 linked such that multiple sections are based at the same address, GDB
4091 will decide which section to use for symbolic info. You can choose to
4092 control the decision manually, using overlay commands, or implement
4093 additional target-side support and use "overlay load-target" to bring
4094 in the overlay mapping. Do "help overlay" for more detail.
4098 The command "info symbol <address>" displays information about
4099 the symbol at the specified address.
4103 The standard remote protocol now includes an extension that allows
4104 asynchronous collection and display of trace data. This requires
4105 extensive support in the target-side debugging stub. Tracing mode
4106 includes a new interaction mode in GDB and new commands: see the
4107 file tracepoint.c for more details.
4111 Configurations for embedded MIPS now include a simulator contributed
4112 by Cygnus Solutions. The simulator supports the instruction sets
4113 of most MIPS variants.
4117 Sparc configurations may now include the ERC32 simulator contributed
4118 by the European Space Agency. The simulator is not built into
4119 Sparc targets by default; configure with --enable-sim to include it.
4123 For target configurations that may include multiple variants of a
4124 basic architecture (such as MIPS and SH), you may now set the
4125 architecture explicitly. "set arch" sets, "info arch" lists
4126 the possible architectures.
4128 *** Changes in GDB-4.16:
4130 * New native configurations
4132 Windows 95, x86 Windows NT i[345]86-*-cygwin32
4133 M68K NetBSD m68k-*-netbsd*
4134 PowerPC AIX 4.x powerpc-*-aix*
4135 PowerPC MacOS powerpc-*-macos*
4136 PowerPC Windows NT powerpcle-*-cygwin32
4137 RS/6000 AIX 4.x rs6000-*-aix4*
4141 ARM with RDP protocol arm-*-*
4142 I960 with MON960 i960-*-coff
4143 MIPS VxWorks mips*-*-vxworks*
4144 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
4145 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
4147 Matra Sparclet sparclet-*-*
4151 The powerpc-eabi configuration now includes the PSIM simulator,
4152 contributed by Andrew Cagney, with assistance from Mike Meissner.
4153 PSIM is a very elaborate model of the PowerPC, including not only
4154 basic instruction set execution, but also details of execution unit
4155 performance and I/O hardware. See sim/ppc/README for more details.
4159 GDB now works with Solaris 2.5.
4161 * Windows 95/NT native
4163 GDB will now work as a native debugger on Windows 95 and Windows NT.
4164 To build it from source, you must use the "gnu-win32" environment,
4165 which uses a DLL to emulate enough of Unix to run the GNU tools.
4166 Further information, binaries, and sources are available at
4167 ftp.cygnus.com, under pub/gnu-win32.
4169 * dont-repeat command
4171 If a user-defined command includes the command `dont-repeat', then the
4172 command will not be repeated if the user just types return. This is
4173 useful if the command is time-consuming to run, so that accidental
4174 extra keystrokes don't run the same command many times.
4176 * Send break instead of ^C
4178 The standard remote protocol now includes an option to send a break
4179 rather than a ^C to the target in order to interrupt it. By default,
4180 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
4182 * Remote protocol timeout
4184 The standard remote protocol includes a new variable `remotetimeout'
4185 that allows you to set the number of seconds before GDB gives up trying
4186 to read from the target. The default value is 2.
4188 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
4190 By default GDB will automatically keep track of objects as they are
4191 loaded and unloaded by the dynamic linker. By using the command `set
4192 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
4193 when shared library events occur, thus allowing you to set breakpoints
4194 in shared libraries which are explicitly loaded by the inferior.
4196 Note this feature does not work on hpux8. On hpux9 you must link
4197 /usr/lib/end.o into your program. This feature should work
4198 automatically on hpux10.
4200 * Irix 5.x hardware watchpoint support
4202 Irix 5 configurations now support the use of hardware watchpoints.
4204 * Mips protocol "SYN garbage limit"
4206 When debugging a Mips target using the `target mips' protocol, you
4207 may set the number of characters that GDB will ignore by setting
4208 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
4209 every character. The default value is 1050.
4211 * Recording and replaying remote debug sessions
4213 If you set `remotelogfile' to the name of a file, gdb will write to it
4214 a recording of a remote debug session. This recording may then be
4215 replayed back to gdb using "gdbreplay". See gdbserver/README for
4216 details. This is useful when you have a problem with GDB while doing
4217 remote debugging; you can make a recording of the session and send it
4218 to someone else, who can then recreate the problem.
4220 * Speedups for remote debugging
4222 GDB includes speedups for downloading and stepping MIPS systems using
4223 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
4224 and more efficient S-record downloading.
4226 * Memory use reductions and statistics collection
4228 GDB now uses less memory and reports statistics about memory usage.
4229 Try the `maint print statistics' command, for example.
4231 *** Changes in GDB-4.15:
4233 * Psymtabs for XCOFF
4235 The symbol reader for AIX GDB now uses partial symbol tables. This
4236 can greatly improve startup time, especially for large executables.
4238 * Remote targets use caching
4240 Remote targets now use a data cache to speed up communication with the
4241 remote side. The data cache could lead to incorrect results because
4242 it doesn't know about volatile variables, thus making it impossible to
4243 debug targets which use memory mapped I/O devices. `set remotecache
4244 off' turns the the data cache off.
4246 * Remote targets may have threads
4248 The standard remote protocol now includes support for multiple threads
4249 in the target system, using new protocol commands 'H' and 'T'. See
4250 gdb/remote.c for details.
4254 If GDB is configured with `--enable-netrom', then it will include
4255 support for the NetROM ROM emulator from XLNT Designs. The NetROM
4256 acts as though it is a bank of ROM on the target board, but you can
4257 write into it over the network. GDB's support consists only of
4258 support for fast loading into the emulated ROM; to debug, you must use
4259 another protocol, such as standard remote protocol. The usual
4260 sequence is something like
4262 target nrom <netrom-hostname>
4264 target remote <netrom-hostname>:1235
4268 GDB now includes support for the Apple Macintosh, as a host only. It
4269 may be run as either an MPW tool or as a standalone application, and
4270 it can debug through the serial port. All the usual GDB commands are
4271 available, but to the target command, you must supply "serial" as the
4272 device type instead of "/dev/ttyXX". See mpw-README in the main
4273 directory for more information on how to build. The MPW configuration
4274 scripts */mpw-config.in support only a few targets, and only the
4275 mips-idt-ecoff target has been tested.
4279 GDB configuration now uses autoconf. This is not user-visible,
4280 but does simplify configuration and building.
4284 GDB now supports hpux10.
4286 *** Changes in GDB-4.14:
4288 * New native configurations
4290 x86 FreeBSD i[345]86-*-freebsd
4291 x86 NetBSD i[345]86-*-netbsd
4292 NS32k NetBSD ns32k-*-netbsd
4293 Sparc NetBSD sparc-*-netbsd
4297 A29K VxWorks a29k-*-vxworks
4298 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
4299 CPU32 EST-300 emulator m68*-*-est*
4300 PowerPC ELF powerpc-*-elf
4303 * Alpha OSF/1 support for procfs
4305 GDB now supports procfs under OSF/1-2.x and higher, which makes it
4306 possible to attach to running processes. As the mounting of the /proc
4307 filesystem is optional on the Alpha, GDB automatically determines
4308 the availability of /proc during startup. This can lead to problems
4309 if /proc is unmounted after GDB has been started.
4311 * Arguments to user-defined commands
4313 User commands may accept up to 10 arguments separated by whitespace.
4314 Arguments are accessed within the user command via $arg0..$arg9. A
4317 print $arg0 + $arg1 + $arg2
4319 To execute the command use:
4322 Defines the command "adder" which prints the sum of its three arguments.
4323 Note the arguments are text substitutions, so they may reference variables,
4324 use complex expressions, or even perform inferior function calls.
4326 * New `if' and `while' commands
4328 This makes it possible to write more sophisticated user-defined
4329 commands. Both commands take a single argument, which is the
4330 expression to evaluate, and must be followed by the commands to
4331 execute, one per line, if the expression is nonzero, the list being
4332 terminated by the word `end'. The `if' command list may include an
4333 `else' word, which causes the following commands to be executed only
4334 if the expression is zero.
4336 * Fortran source language mode
4338 GDB now includes partial support for Fortran 77. It will recognize
4339 Fortran programs and can evaluate a subset of Fortran expressions, but
4340 variables and functions may not be handled correctly. GDB will work
4341 with G77, but does not yet know much about symbols emitted by other
4344 * Better HPUX support
4346 Most debugging facilities now work on dynamic executables for HPPAs
4347 running hpux9 or later. You can attach to running dynamically linked
4348 processes, but by default the dynamic libraries will be read-only, so
4349 for instance you won't be able to put breakpoints in them. To change
4350 that behavior do the following before running the program:
4356 This will cause the libraries to be mapped private and read-write.
4357 To revert to the normal behavior, do this:
4363 You cannot set breakpoints or examine data in the library until after
4364 the library is loaded if the function/data symbols do not have
4367 GDB can now also read debug symbols produced by the HP C compiler on
4368 HPPAs (sorry, no C++, Fortran or 68k support).
4370 * Target byte order now dynamically selectable
4372 You can choose which byte order to use with a target system, via the
4373 commands "set endian big" and "set endian little", and you can see the
4374 current setting by using "show endian". You can also give the command
4375 "set endian auto", in which case GDB will use the byte order
4376 associated with the executable. Currently, only embedded MIPS
4377 configurations support dynamic selection of target byte order.
4379 * New DOS host serial code
4381 This version uses DPMI interrupts to handle buffered I/O, so you
4382 no longer need to run asynctsr when debugging boards connected to
4385 *** Changes in GDB-4.13:
4387 * New "complete" command
4389 This lists all the possible completions for the rest of the line, if it
4390 were to be given as a command itself. This is intended for use by emacs.
4392 * Trailing space optional in prompt
4394 "set prompt" no longer adds a space for you after the prompt you set. This
4395 allows you to set a prompt which ends in a space or one that does not.
4397 * Breakpoint hit counts
4399 "info break" now displays a count of the number of times the breakpoint
4400 has been hit. This is especially useful in conjunction with "ignore"; you
4401 can ignore a large number of breakpoint hits, look at the breakpoint info
4402 to see how many times the breakpoint was hit, then run again, ignoring one
4403 less than that number, and this will get you quickly to the last hit of
4406 * Ability to stop printing at NULL character
4408 "set print null-stop" will cause GDB to stop printing the characters of
4409 an array when the first NULL is encountered. This is useful when large
4410 arrays actually contain only short strings.
4412 * Shared library breakpoints
4414 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4415 breakpoints in shared libraries before the executable is run.
4417 * Hardware watchpoints
4419 There is a new hardware breakpoint for the watch command for sparclite
4420 targets. See gdb/sparclite/hw_breakpoint.note.
4422 Hardware watchpoints are also now supported under GNU/Linux.
4426 Annotations have been added. These are for use with graphical interfaces,
4427 and are still experimental. Currently only gdba.el uses these.
4429 * Improved Irix 5 support
4431 GDB now works properly with Irix 5.2.
4433 * Improved HPPA support
4435 GDB now works properly with the latest GCC and GAS.
4437 * New native configurations
4439 Sequent PTX4 i[34]86-sequent-ptx4
4440 HPPA running OSF/1 hppa*-*-osf*
4441 Atari TT running SVR4 m68*-*-sysv4*
4442 RS/6000 LynxOS rs6000-*-lynxos*
4446 OS/9000 i[34]86-*-os9k
4447 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4450 * Hitachi SH7000 and E7000-PC ICE support
4452 There is now support for communicating with the Hitachi E7000-PC ICE.
4453 This is available automatically when GDB is configured for the SH.
4457 As usual, a variety of small fixes and improvements, both generic
4458 and configuration-specific. See the ChangeLog for more detail.
4460 *** Changes in GDB-4.12:
4462 * Irix 5 is now supported
4466 GDB-4.12 on the HPPA has a number of changes which make it unable
4467 to debug the output from the currently released versions of GCC and
4468 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4469 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4470 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4473 *** Changes in GDB-4.11:
4475 * User visible changes:
4479 The "set remotedebug" option is now consistent between the mips remote
4480 target, remote targets using the gdb-specific protocol, UDI (AMD's
4481 debug protocol for the 29k) and the 88k bug monitor. It is now an
4482 integer specifying a debug level (normally 0 or 1, but 2 means more
4483 debugging info for the mips target).
4485 * DEC Alpha native support
4487 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4488 debug info, but GDB works fairly well with the DEC compiler and should
4489 work with a future GCC release. See the README file for a few
4490 Alpha-specific notes.
4492 * Preliminary thread implementation
4494 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4496 * LynxOS native and target support for 386
4498 This release has been hosted on LynxOS 2.2, and also can be configured
4499 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4502 * Improvements in C++ mangling/demangling.
4504 This release has much better g++ debugging, specifically in name
4505 mangling/demangling, virtual function calls, print virtual table,
4506 call methods, ...etc.
4508 *** Changes in GDB-4.10:
4510 * User visible changes:
4512 Remote debugging using the GDB-specific (`target remote') protocol now
4513 supports the `load' command. This is only useful if you have some
4514 other way of getting the stub to the target system, and you can put it
4515 somewhere in memory where it won't get clobbered by the download.
4517 Filename completion now works.
4519 When run under emacs mode, the "info line" command now causes the
4520 arrow to point to the line specified. Also, "info line" prints
4521 addresses in symbolic form (as well as hex).
4523 All vxworks based targets now support a user settable option, called
4524 vxworks-timeout. This option represents the number of seconds gdb
4525 should wait for responses to rpc's. You might want to use this if
4526 your vxworks target is, perhaps, a slow software simulator or happens
4527 to be on the far side of a thin network line.
4531 This release contains support for using a DEC alpha as a GDB host for
4532 cross debugging. Native alpha debugging is not supported yet.
4535 *** Changes in GDB-4.9:
4539 This is the first GDB release which is accompanied by a matching testsuite.
4540 The testsuite requires installation of dejagnu, which should be available
4541 via ftp from most sites that carry GNU software.
4545 'Cfront' style demangling has had its name changed to 'ARM' style, to
4546 emphasize that it was written from the specifications in the C++ Annotated
4547 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4548 disclaimers, it still generated too much confusion with users attempting to
4549 use gdb with AT&T cfront.
4553 GDB now uses a standard remote interface to a simulator library.
4554 So far, the library contains simulators for the Zilog Z8001/2, the
4555 Hitachi H8/300, H8/500 and Super-H.
4557 * New targets supported
4559 H8/300 simulator h8300-hitachi-hms or h8300hms
4560 H8/500 simulator h8500-hitachi-hms or h8500hms
4561 SH simulator sh-hitachi-hms or sh
4562 Z8000 simulator z8k-zilog-none or z8ksim
4563 IDT MIPS board over serial line mips-idt-ecoff
4565 Cross-debugging to GO32 targets is supported. It requires a custom
4566 version of the i386-stub.c module which is integrated with the
4567 GO32 memory extender.
4569 * New remote protocols
4571 MIPS remote debugging protocol.
4573 * New source languages supported
4575 This version includes preliminary support for Chill, a Pascal like language
4576 used by telecommunications companies. Chill support is also being integrated
4577 into the GNU compiler, but we don't know when it will be publically available.
4580 *** Changes in GDB-4.8:
4582 * HP Precision Architecture supported
4584 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4585 version of this support was available as a set of patches from the
4586 University of Utah. GDB does not support debugging of programs
4587 compiled with the HP compiler, because HP will not document their file
4588 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4589 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4591 Many problems in the preliminary version have been fixed.
4593 * Faster and better demangling
4595 We have improved template demangling and fixed numerous bugs in the GNU style
4596 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4597 character types (wchar_t) are now supported. Demangling of each symbol is now
4598 only done once, and is cached when the symbol table for a file is read in.
4599 This results in a small increase in memory usage for C programs, a moderate
4600 increase in memory usage for C++ programs, and a fantastic speedup in
4603 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4604 from the specifications in the Annotated Reference Manual, which AT&T's
4605 compiler does not actually implement.
4607 * G++ multiple inheritance compiler problem
4609 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4610 inheritance lattices was reworked to properly discover ambiguities. We
4611 recently found an example which causes this new algorithm to fail in a
4612 very subtle way, producing bad debug information for those classes.
4613 The file 'gcc.patch' (in this directory) can be applied to gcc to
4614 circumvent the problem. A future GCC release will contain a complete
4617 The previous G++ debug info problem (mentioned below for the gdb-4.7
4618 release) is fixed in gcc version 2.3.2.
4620 * Improved configure script
4622 The `configure' script will now attempt to guess your system type if
4623 you don't supply a host system type. The old scheme of supplying a
4624 host system triplet is preferable over using this. All the magic is
4625 done in the new `config.guess' script. Examine it for details.
4627 We have also brought our configure script much more in line with the FSF's
4628 version. It now supports the --with-xxx options. In particular,
4629 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4630 The resulting GDB will not be able to read arbitrary object file formats --
4631 only the format ``expected'' to be used on the configured target system.
4632 We hope to make this the default in a future release.
4634 * Documentation improvements
4636 There's new internal documentation on how to modify GDB, and how to
4637 produce clean changes to the code. We implore people to read it
4638 before submitting changes.
4640 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4641 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4642 `info' files are also provided. To build `info' files from scratch,
4643 you will need the latest `makeinfo' release, which will be available in
4644 a future texinfo-X.Y release.
4646 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4647 We're not sure exactly which versions have this problem, but it has
4648 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4649 or better. If that isn't possible, there is a patch in
4650 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4651 around this problem.
4655 GDB now supports array constants that can be used in expressions typed in by
4656 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4657 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4660 The new directory `gdb/sparclite' contains a program that demonstrates
4661 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4663 * New native hosts supported
4665 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4666 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4668 * New targets supported
4670 AMD 29k family via UDI a29k-amd-udi or udi29k
4672 * New file formats supported
4674 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4675 HPUX core files, and SCO 3.2v2 core files.
4679 Attaching to processes now works again; thanks for the many bug reports.
4681 We have also stomped on a bunch of core dumps caused by
4682 printf_filtered("%s") problems.
4684 We eliminated a copyright problem on the rpc and ptrace header files
4685 for VxWorks, which was discovered at the last minute during the 4.7
4686 release. You should now be able to build a VxWorks GDB.
4688 You can now interrupt gdb while an attached process is running. This
4689 will cause the attached process to stop, and give control back to GDB.
4691 We fixed problems caused by using too many file descriptors
4692 for reading symbols from object files and libraries. This was
4693 especially a problem for programs that used many (~100) shared
4696 The `step' command now only enters a subroutine if there is line number
4697 information for the subroutine. Otherwise it acts like the `next'
4698 command. Previously, `step' would enter subroutines if there was
4699 any debugging information about the routine. This avoids problems
4700 when using `cc -g1' on MIPS machines.
4702 * Internal improvements
4704 GDB's internal interfaces have been improved to make it easier to support
4705 debugging of multiple languages in the future.
4707 GDB now uses a common structure for symbol information internally.
4708 Minimal symbols (derived from linkage symbols in object files), partial
4709 symbols (from a quick scan of debug information), and full symbols
4710 contain a common subset of information, making it easier to write
4711 shared code that handles any of them.
4713 * New command line options
4715 We now accept --silent as an alias for --quiet.
4719 The memory-mapped-malloc library is now licensed under the GNU Library
4720 General Public License.
4722 *** Changes in GDB-4.7:
4724 * Host/native/target split
4726 GDB has had some major internal surgery to untangle the support for
4727 hosts and remote targets. Now, when you configure GDB for a remote
4728 target, it will no longer load in all of the support for debugging
4729 local programs on the host. When fully completed and tested, this will
4730 ensure that arbitrary host/target combinations are possible.
4732 The primary conceptual shift is to separate the non-portable code in
4733 GDB into three categories. Host specific code is required any time GDB
4734 is compiled on that host, regardless of the target. Target specific
4735 code relates to the peculiarities of the target, but can be compiled on
4736 any host. Native specific code is everything else: it can only be
4737 built when the host and target are the same system. Child process
4738 handling and core file support are two common `native' examples.
4740 GDB's use of /proc for controlling Unix child processes is now cleaner.
4741 It has been split out into a single module under the `target_ops' vector,
4742 plus two native-dependent functions for each system that uses /proc.
4744 * New hosts supported
4746 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4747 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4748 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4750 * New targets supported
4752 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4753 68030 and CPU32 m68030-*-*, m68332-*-*
4755 * New native hosts supported
4757 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4758 (386bsd is not well tested yet)
4759 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4761 * New file formats supported
4763 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4764 supports reading of `a.out.adobe' object files, which are an a.out
4765 format extended with minimal information about multiple sections.
4769 `show copying' is the same as the old `info copying'.
4770 `show warranty' is the same as `info warrantee'.
4771 These were renamed for consistency. The old commands continue to work.
4773 `info handle' is a new alias for `info signals'.
4775 You can now define pre-command hooks, which attach arbitrary command
4776 scripts to any command. The commands in the hook will be executed
4777 prior to the user's command. You can also create a hook which will be
4778 executed whenever the program stops. See gdb.texinfo.
4782 We now deal with Cfront style name mangling, and can even extract type
4783 info from mangled symbols. GDB can automatically figure out which
4784 symbol mangling style your C++ compiler uses.
4786 Calling of methods and virtual functions has been improved as well.
4790 The crash that occured when debugging Sun Ansi-C compiled binaries is
4791 fixed. This was due to mishandling of the extra N_SO stabs output
4794 We also finally got Ultrix 4.2 running in house, and fixed core file
4795 support, with help from a dozen people on the net.
4797 John M. Farrell discovered that the reason that single-stepping was so
4798 slow on all of the Mips based platforms (primarily SGI and DEC) was
4799 that we were trying to demangle and lookup a symbol used for internal
4800 purposes on every instruction that was being stepped through. Changing
4801 the name of that symbol so that it couldn't be mistaken for a C++
4802 mangled symbol sped things up a great deal.
4804 Rich Pixley sped up symbol lookups in general by getting much smarter
4805 about when C++ symbol mangling is necessary. This should make symbol
4806 completion (TAB on the command line) much faster. It's not as fast as
4807 we'd like, but it's significantly faster than gdb-4.6.
4811 A new user controllable variable 'call_scratch_address' can
4812 specify the location of a scratch area to be used when GDB
4813 calls a function in the target. This is necessary because the
4814 usual method of putting the scratch area on the stack does not work
4815 in systems that have separate instruction and data spaces.
4817 We integrated changes to support the 29k UDI (Universal Debugger
4818 Interface), but discovered at the last minute that we didn't have all
4819 of the appropriate copyright paperwork. We are working with AMD to
4820 resolve this, and hope to have it available soon.
4824 We have sped up the remote serial line protocol, especially for targets
4825 with lots of registers. It now supports a new `expedited status' ('T')
4826 message which can be used in place of the existing 'S' status message.
4827 This allows the remote stub to send only the registers that GDB
4828 needs to make a quick decision about single-stepping or conditional
4829 breakpoints, eliminating the need to fetch the entire register set for
4830 each instruction being stepped through.
4832 The GDB remote serial protocol now implements a write-through cache for
4833 registers, only re-reading the registers if the target has run.
4835 There is also a new remote serial stub for SPARC processors. You can
4836 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4837 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4838 processor with a serial port.
4842 Configure.in files have become much easier to read and modify. A new
4843 `table driven' format makes it more obvious what configurations are
4844 supported, and what files each one uses.
4848 There is a new opcodes library which will eventually contain all of the
4849 disassembly routines and opcode tables. At present, it only contains
4850 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4851 disassembler (binutils/objdump) to share these routines.
4853 The libiberty library is now copylefted under the GNU Library General
4854 Public License. This allows more liberal use, and was done so libg++
4855 can use it. This makes no difference to GDB, since the Library License
4856 grants all the rights from the General Public License.
4860 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4861 reference to the stabs symbol info used by the debugger. It is (as far
4862 as we know) the only published document on this fascinating topic. We
4863 encourage you to read it, compare it to the stabs information on your
4864 system, and send improvements on the document in general (to
4865 bug-gdb@prep.ai.mit.edu).
4867 And, of course, many bugs have been fixed.
4870 *** Changes in GDB-4.6:
4872 * Better support for C++ function names
4874 GDB now accepts as input the "demangled form" of C++ overloaded function
4875 names and member function names, and can do command completion on such names
4876 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4877 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4878 Make use of command completion, it is your friend.
4880 GDB also now accepts a variety of C++ mangled symbol formats. They are
4881 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4882 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4883 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4884 for the list of formats.
4886 * G++ symbol mangling problem
4888 Recent versions of gcc have a bug in how they emit debugging information for
4889 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4890 directory) can be applied to gcc to fix the problem. Alternatively, if you
4891 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4892 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4893 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4896 * New 'maintenance' command
4898 All of the commands related to hacking GDB internals have been moved out of
4899 the main command set, and now live behind the 'maintenance' command. This
4900 can also be abbreviated as 'mt'. The following changes were made:
4902 dump-me -> maintenance dump-me
4903 info all-breakpoints -> maintenance info breakpoints
4904 printmsyms -> maintenance print msyms
4905 printobjfiles -> maintenance print objfiles
4906 printpsyms -> maintenance print psymbols
4907 printsyms -> maintenance print symbols
4909 The following commands are new:
4911 maintenance demangle Call internal GDB demangler routine to
4912 demangle a C++ link name and prints the result.
4913 maintenance print type Print a type chain for a given symbol
4915 * Change to .gdbinit file processing
4917 We now read the $HOME/.gdbinit file before processing the argv arguments
4918 (e.g. reading symbol files or core files). This allows global parameters to
4919 be set, which will apply during the symbol reading. The ./.gdbinit is still
4920 read after argv processing.
4922 * New hosts supported
4924 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4926 GNU/Linux support i386-unknown-linux or linux
4928 We are also including code to support the HP/PA running BSD and HPUX. This
4929 is almost guaranteed not to work, as we didn't have time to test or build it
4930 for this release. We are including it so that the more adventurous (or
4931 masochistic) of you can play with it. We also had major problems with the
4932 fact that the compiler that we got from HP doesn't support the -g option.
4935 * New targets supported
4937 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4939 * More smarts about finding #include files
4941 GDB now remembers the compilation directory for all include files, and for
4942 all files from which C is generated (like yacc and lex sources). This
4943 greatly improves GDB's ability to find yacc/lex sources, and include files,
4944 especially if you are debugging your program from a directory different from
4945 the one that contains your sources.
4947 We also fixed a bug which caused difficulty with listing and setting
4948 breakpoints in include files which contain C code. (In the past, you had to
4949 try twice in order to list an include file that you hadn't looked at before.)
4951 * Interesting infernals change
4953 GDB now deals with arbitrary numbers of sections, where the symbols for each
4954 section must be relocated relative to that section's landing place in the
4955 target's address space. This work was needed to support ELF with embedded
4956 stabs used by Solaris-2.0.
4958 * Bug fixes (of course!)
4960 There have been loads of fixes for the following things:
4961 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4962 i960, stabs, DOS(GO32), procfs, etc...
4964 See the ChangeLog for details.
4966 *** Changes in GDB-4.5:
4968 * New machines supported (host and target)
4970 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4972 SGI Irix-4.x mips-sgi-irix4 or iris4
4974 * New malloc package
4976 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4977 Mmalloc is capable of handling mutiple heaps of memory. It is also
4978 capable of saving a heap to a file, and then mapping it back in later.
4979 This can be used to greatly speedup the startup of GDB by using a
4980 pre-parsed symbol table which lives in a mmalloc managed heap. For
4981 more details, please read mmalloc/mmalloc.texi.
4985 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4986 'help info proc' for details.
4988 * MIPS ecoff symbol table format
4990 The code that reads MIPS symbol table format is now supported on all hosts.
4991 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4994 * File name changes for MS-DOS
4996 Many files in the config directories have been renamed to make it easier to
4997 support GDB on MS-DOSe systems (which have very restrictive file name
4998 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4999 environment) is close to working but has some remaining problems. Note
5000 that debugging of DOS programs is not supported, due to limitations
5001 in the ``operating system'', but it can be used to host cross-debugging.
5003 * Cross byte order fixes
5005 Many fixes have been made to support cross debugging of Sparc and MIPS
5006 targets from hosts whose byte order differs.
5008 * New -mapped and -readnow options
5010 If memory-mapped files are available on your system through the 'mmap'
5011 system call, you can use the -mapped option on the `file' or
5012 `symbol-file' commands to cause GDB to write the symbols from your
5013 program into a reusable file. If the program you are debugging is
5014 called `/path/fred', the mapped symbol file will be `./fred.syms'.
5015 Future GDB debugging sessions will notice the presence of this file,
5016 and will quickly map in symbol information from it, rather than reading
5017 the symbol table from the executable program. Using the '-mapped'
5018 option in a GDB `file' or `symbol-file' command has the same effect as
5019 starting GDB with the '-mapped' command-line option.
5021 You can cause GDB to read the entire symbol table immediately by using
5022 the '-readnow' option with any of the commands that load symbol table
5023 information (or on the GDB command line). This makes the command
5024 slower, but makes future operations faster.
5026 The -mapped and -readnow options are typically combined in order to
5027 build a `fred.syms' file that contains complete symbol information.
5028 A simple GDB invocation to do nothing but build a `.syms' file for future
5031 gdb -batch -nx -mapped -readnow programname
5033 The `.syms' file is specific to the host machine on which GDB is run.
5034 It holds an exact image of GDB's internal symbol table. It cannot be
5035 shared across multiple host platforms.
5037 * longjmp() handling
5039 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
5040 siglongjmp() without losing control. This feature has not yet been ported to
5041 all systems. It currently works on many 386 platforms, all MIPS-based
5042 platforms (SGI, DECstation, etc), and Sun3/4.
5046 Preliminary work has been put in to support the new Solaris OS from Sun. At
5047 this time, it can control and debug processes, but it is not capable of
5052 As always, many many bug fixes. The major areas were with g++, and mipsread.
5053 People using the MIPS-based platforms should experience fewer mysterious
5054 crashes and trashed symbol tables.
5056 *** Changes in GDB-4.4:
5058 * New machines supported (host and target)
5060 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5062 BSD Reno on Vax vax-dec-bsd
5063 Ultrix on Vax vax-dec-ultrix
5065 * New machines supported (target)
5067 AMD 29000 embedded, using EBMON a29k-none-none
5071 GDB continues to improve its handling of C++. `References' work better.
5072 The demangler has also been improved, and now deals with symbols mangled as
5073 per the Annotated C++ Reference Guide.
5075 GDB also now handles `stabs' symbol information embedded in MIPS
5076 `ecoff' symbol tables. Since the ecoff format was not easily
5077 extensible to handle new languages such as C++, this appeared to be a
5078 good way to put C++ debugging info into MIPS binaries. This option
5079 will be supported in the GNU C compiler, version 2, when it is
5082 * New features for SVR4
5084 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
5085 shared libraries. Debugging dynamically linked programs should present
5086 only minor differences from debugging statically linked programs.
5088 The `info proc' command will print out information about any process
5089 on an SVR4 system (including the one you are debugging). At the moment,
5090 it prints the address mappings of the process.
5092 If you bring up GDB on another SVR4 system, please send mail to
5093 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
5095 * Better dynamic linking support in SunOS
5097 Reading symbols from shared libraries which contain debugging symbols
5098 now works properly. However, there remain issues such as automatic
5099 skipping of `transfer vector' code during function calls, which
5100 make it harder to debug code in a shared library, than to debug the
5101 same code linked statically.
5105 GDB is now using the latest `getopt' routines from the FSF. This
5106 version accepts the -- prefix for options with long names. GDB will
5107 continue to accept the old forms (-option and +option) as well.
5108 Various single letter abbreviations for options have been explicity
5109 added to the option table so that they won't get overshadowed in the
5110 future by other options that begin with the same letter.
5114 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
5115 Many assorted bugs have been handled. Many more remain to be handled.
5116 See the various ChangeLog files (primarily in gdb and bfd) for details.
5119 *** Changes in GDB-4.3:
5121 * New machines supported (host and target)
5123 Amiga 3000 running Amix m68k-cbm-svr4 or amix
5124 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
5125 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5127 * Almost SCO Unix support
5129 We had hoped to support:
5130 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
5131 (except for core file support), but we discovered very late in the release
5132 that it has problems with process groups that render gdb unusable. Sorry
5133 about that. I encourage people to fix it and post the fixes.
5135 * Preliminary ELF and DWARF support
5137 GDB can read ELF object files on System V Release 4, and can handle
5138 debugging records for C, in DWARF format, in ELF files. This support
5139 is preliminary. If you bring up GDB on another SVR4 system, please
5140 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
5145 GDB now uses the latest `readline' library. One user-visible change
5146 is that two tabs will list possible command completions, which previously
5147 required typing M-? (meta-question mark, or ESC ?).
5151 The `stepi' bug that many of you noticed has been squashed.
5152 Many bugs in C++ have been handled. Many more remain to be handled.
5153 See the various ChangeLog files (primarily in gdb and bfd) for details.
5155 * State of the MIPS world (in case you wondered):
5157 GDB can understand the symbol tables emitted by the compilers
5158 supplied by most vendors of MIPS-based machines, including DEC. These
5159 symbol tables are in a format that essentially nobody else uses.
5161 Some versions of gcc come with an assembler post-processor called
5162 mips-tfile. This program is required if you want to do source-level
5163 debugging of gcc-compiled programs. I believe FSF does not ship
5164 mips-tfile with gcc version 1, but it will eventually come with gcc
5167 Debugging of g++ output remains a problem. g++ version 1.xx does not
5168 really support it at all. (If you're lucky, you should be able to get
5169 line numbers and stack traces to work, but no parameters or local
5170 variables.) With some work it should be possible to improve the
5173 When gcc version 2 is released, you will have somewhat better luck.
5174 However, even then you will get confusing results for inheritance and
5177 We will eventually provide full debugging of g++ output on
5178 DECstations. This will probably involve some kind of stabs-in-ecoff
5179 encapulation, but the details have not been worked out yet.
5182 *** Changes in GDB-4.2:
5184 * Improved configuration
5186 Only one copy of `configure' exists now, and it is not self-modifying.
5187 Porting BFD is simpler.
5191 The `step' and `next' commands now only stop at the first instruction
5192 of a source line. This prevents the multiple stops that used to occur
5193 in switch statements, for-loops, etc. `Step' continues to stop if a
5194 function that has debugging information is called within the line.
5198 Lots of small bugs fixed. More remain.
5200 * New host supported (not target)
5202 Intel 386 PC clone running Mach i386-none-mach
5205 *** Changes in GDB-4.1:
5207 * Multiple source language support
5209 GDB now has internal scaffolding to handle several source languages.
5210 It determines the type of each source file from its filename extension,
5211 and will switch expression parsing and number formatting to match the
5212 language of the function in the currently selected stack frame.
5213 You can also specifically set the language to be used, with
5214 `set language c' or `set language modula-2'.
5218 GDB now has preliminary support for the GNU Modula-2 compiler,
5219 currently under development at the State University of New York at
5220 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
5221 continue through the fall of 1991 and into 1992.
5223 Other Modula-2 compilers are currently not supported, and attempting to
5224 debug programs compiled with them will likely result in an error as the
5225 symbol table is read. Feel free to work on it, though!
5227 There are hooks in GDB for strict type checking and range checking,
5228 in the `Modula-2 philosophy', but they do not currently work.
5232 GDB can now write to executable and core files (e.g. patch
5233 a variable's value). You must turn this switch on, specify
5234 the file ("exec foo" or "core foo"), *then* modify it, e.g.
5235 by assigning a new value to a variable. Modifications take
5238 * Automatic SunOS shared library reading
5240 When you run your program, GDB automatically determines where its
5241 shared libraries (if any) have been loaded, and reads their symbols.
5242 The `share' command is no longer needed. This also works when
5243 examining core files.
5247 You can specify the number of lines that the `list' command shows.
5250 * New machines supported (host and target)
5252 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5253 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
5254 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
5256 * New hosts supported (not targets)
5258 IBM RT/PC: romp-ibm-aix or rtpc
5260 * New targets supported (not hosts)
5262 AMD 29000 embedded with COFF a29k-none-coff
5263 AMD 29000 embedded with a.out a29k-none-aout
5264 Ultracomputer remote kernel debug a29k-nyu-kern
5266 * New remote interfaces
5272 *** Changes in GDB-4.0:
5276 Wide output is wrapped at good places to make the output more readable.
5278 Gdb now supports cross-debugging from a host machine of one type to a
5279 target machine of another type. Communication with the target system
5280 is over serial lines. The ``target'' command handles connecting to the
5281 remote system; the ``load'' command will download a program into the
5282 remote system. Serial stubs for the m68k and i386 are provided. Gdb
5283 also supports debugging of realtime processes running under VxWorks,
5284 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
5285 stub on the target system.
5287 New CPUs supported include the AMD 29000 and Intel 960.
5289 GDB now reads object files and symbol tables via a ``binary file''
5290 library, which allows a single copy of GDB to debug programs of multiple
5291 object file types such as a.out and coff.
5293 There is now a GDB reference card in "doc/refcard.tex". (Make targets
5294 refcard.dvi and refcard.ps are available to format it).
5297 * Control-Variable user interface simplified
5299 All variables that control the operation of the debugger can be set
5300 by the ``set'' command, and displayed by the ``show'' command.
5302 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
5303 ``Show prompt'' produces the response:
5304 Gdb's prompt is new-gdb=>.
5306 What follows are the NEW set commands. The command ``help set'' will
5307 print a complete list of old and new set commands. ``help set FOO''
5308 will give a longer description of the variable FOO. ``show'' will show
5309 all of the variable descriptions and their current settings.
5311 confirm on/off: Enables warning questions for operations that are
5312 hard to recover from, e.g. rerunning the program while
5313 it is already running. Default is ON.
5315 editing on/off: Enables EMACS style command line editing
5316 of input. Previous lines can be recalled with
5317 control-P, the current line can be edited with control-B,
5318 you can search for commands with control-R, etc.
5321 history filename NAME: NAME is where the gdb command history
5322 will be stored. The default is .gdb_history,
5323 or the value of the environment variable
5326 history size N: The size, in commands, of the command history. The
5327 default is 256, or the value of the environment variable
5330 history save on/off: If this value is set to ON, the history file will
5331 be saved after exiting gdb. If set to OFF, the
5332 file will not be saved. The default is OFF.
5334 history expansion on/off: If this value is set to ON, then csh-like
5335 history expansion will be performed on
5336 command line input. The default is OFF.
5338 radix N: Sets the default radix for input and output. It can be set
5339 to 8, 10, or 16. Note that the argument to "radix" is interpreted
5340 in the current radix, so "set radix 10" is always a no-op.
5342 height N: This integer value is the number of lines on a page. Default
5343 is 24, the current `stty rows'' setting, or the ``li#''
5344 setting from the termcap entry matching the environment
5347 width N: This integer value is the number of characters on a line.
5348 Default is 80, the current `stty cols'' setting, or the ``co#''
5349 setting from the termcap entry matching the environment
5352 Note: ``set screensize'' is obsolete. Use ``set height'' and
5353 ``set width'' instead.
5355 print address on/off: Print memory addresses in various command displays,
5356 such as stack traces and structure values. Gdb looks
5357 more ``symbolic'' if you turn this off; it looks more
5358 ``machine level'' with it on. Default is ON.
5360 print array on/off: Prettyprint arrays. New convenient format! Default
5363 print demangle on/off: Print C++ symbols in "source" form if on,
5366 print asm-demangle on/off: Same, for assembler level printouts
5369 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5372 * Support for Epoch Environment.
5374 The epoch environment is a version of Emacs v18 with windowing. One
5375 new command, ``inspect'', is identical to ``print'', except that if you
5376 are running in the epoch environment, the value is printed in its own
5380 * Support for Shared Libraries
5382 GDB can now debug programs and core files that use SunOS shared libraries.
5383 Symbols from a shared library cannot be referenced
5384 before the shared library has been linked with the program (this
5385 happens after you type ``run'' and before the function main() is entered).
5386 At any time after this linking (including when examining core files
5387 from dynamically linked programs), gdb reads the symbols from each
5388 shared library when you type the ``sharedlibrary'' command.
5389 It can be abbreviated ``share''.
5391 sharedlibrary REGEXP: Load shared object library symbols for files
5392 matching a unix regular expression. No argument
5393 indicates to load symbols for all shared libraries.
5395 info sharedlibrary: Status of loaded shared libraries.
5400 A watchpoint stops execution of a program whenever the value of an
5401 expression changes. Checking for this slows down execution
5402 tremendously whenever you are in the scope of the expression, but is
5403 quite useful for catching tough ``bit-spreader'' or pointer misuse
5404 problems. Some machines such as the 386 have hardware for doing this
5405 more quickly, and future versions of gdb will use this hardware.
5407 watch EXP: Set a watchpoint (breakpoint) for an expression.
5409 info watchpoints: Information about your watchpoints.
5411 delete N: Deletes watchpoint number N (same as breakpoints).
5412 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5413 enable N: Re-enables watchpoint number N (same as breakpoints).
5416 * C++ multiple inheritance
5418 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5421 * C++ exception handling
5423 Gdb now supports limited C++ exception handling. Besides the existing
5424 ability to breakpoint on an exception handler, gdb can breakpoint on
5425 the raising of an exception (before the stack is peeled back to the
5428 catch FOO: If there is a FOO exception handler in the dynamic scope,
5429 set a breakpoint to catch exceptions which may be raised there.
5430 Multiple exceptions (``catch foo bar baz'') may be caught.
5432 info catch: Lists all exceptions which may be caught in the
5433 current stack frame.
5436 * Minor command changes
5438 The command ``call func (arg, arg, ...)'' now acts like the print
5439 command, except it does not print or save a value if the function's result
5440 is void. This is similar to dbx usage.
5442 The ``up'' and ``down'' commands now always print the frame they end up
5443 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5444 frames without printing.
5446 * New directory command
5448 'dir' now adds directories to the FRONT of the source search path.
5449 The path starts off empty. Source files that contain debug information
5450 about the directory in which they were compiled can be found even
5451 with an empty path; Sun CC and GCC include this information. If GDB can't
5452 find your source file in the current directory, type "dir .".
5454 * Configuring GDB for compilation
5456 For normal use, type ``./configure host''. See README or gdb.texinfo
5459 GDB now handles cross debugging. If you are remotely debugging between
5460 two different machines, type ``./configure host -target=targ''.
5461 Host is the machine where GDB will run; targ is the machine
5462 where the program that you are debugging will run.