1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * The 'cd' command now defaults to using '~' (the home directory) if not
9 * New configure options
11 --enable-libmcheck/--disable-libmcheck
12 By default, development versions are built with -lmcheck on hosts
13 that support it, in order to help track memory corruption issues.
14 Release versions, on the other hand, are built without -lmcheck
15 by default. The --enable-libmcheck/--disable-libmcheck configure
16 options allow the user to override that default.
18 * New commands (for set/show, see "New options" below)
21 List the BFDs known to GDB.
23 *** Changes in GDB 7.5
25 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
26 for more x32 ABI info.
28 * GDB now supports access to MIPS DSP registers on Linux targets.
30 * GDB now supports debugging microMIPS binaries.
32 * The "info os" command on GNU/Linux can now display information on
33 several new classes of objects managed by the operating system:
34 "info os procgroups" lists process groups
35 "info os files" lists file descriptors
36 "info os sockets" lists internet-domain sockets
37 "info os shm" lists shared-memory regions
38 "info os semaphores" lists semaphores
39 "info os msg" lists message queues
40 "info os modules" lists loaded kernel modules
42 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
43 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
44 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
45 options and inspect the probe arguments using the new $_probe_arg family
46 of convenience variables. You can obtain more information about SystemTap
47 in <http://sourceware.org/systemtap/>.
49 * GDB now supports reversible debugging on ARM, it allows you to
50 debug basic ARM and THUMB instructions, and provides
51 record/replay support.
53 * The option "symbol-reloading" has been deleted as it is no longer used.
57 ** GDB commands implemented in Python can now be put in command class
60 ** The "maint set python print-stack on|off" is now deleted.
62 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
63 apply "flag enum"-style pretty-printing to any enum.
65 ** gdb.lookup_symbol can now work when there is no current frame.
67 ** gdb.Symbol now has a 'line' attribute, holding the line number in
68 the source at which the symbol was defined.
70 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
71 method 'value'. The former indicates whether the symbol needs a
72 frame in order to compute its value, and the latter computes the
75 ** A new method 'referenced_value' on gdb.Value objects which can
76 dereference pointer as well as C++ reference values.
78 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
79 which return the global and static blocks (as gdb.Block objects),
80 of the underlying symbol table, respectively.
82 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
83 object associated with a PC value.
85 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
86 of the address range occupied by code for the current source line.
88 * Go language support.
89 GDB now supports debugging programs written in the Go programming
92 * GDBserver now supports stdio connections.
93 E.g. (gdb) target remote | ssh myhost gdbserver - hello
95 * The binary "gdbtui" can no longer be built or installed.
96 Use "gdb -tui" instead.
98 * GDB will now print "flag" enums specially. A flag enum is one where
99 all the enumerator values have no bits in common when pairwise
100 "and"ed. When printing a value whose type is a flag enum, GDB will
101 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
102 (gdb) print (enum E) 3
105 * The filename part of a linespec will now match trailing components
106 of a source file name. For example, "break gcc/expr.c:1000" will
107 now set a breakpoint in build/gcc/expr.c, but not
110 * The "info proc" and "generate-core-file" commands will now also
111 work on remote targets connected to GDBserver on Linux.
113 * The command "info catch" has been removed. It has been disabled
116 * The "catch exception" and "catch assert" commands now accept
117 a condition at the end of the command, much like the "break"
118 command does. For instance:
120 (gdb) catch exception Constraint_Error if Barrier = True
122 Previously, it was possible to add a condition to such catchpoints,
123 but it had to be done as a second step, after the catchpoint had been
124 created, using the "condition" command.
126 * The "info static-tracepoint-marker" command will now also work on
127 native Linux targets with in-process agent.
129 * GDB can now set breakpoints on inlined functions.
131 * The .gdb_index section has been updated to include symbols for
132 inlined functions. GDB will ignore older .gdb_index sections by
133 default, which could cause symbol files to be loaded more slowly
134 until their .gdb_index sections can be recreated. The new command
135 "set use-deprecated-index-sections on" will cause GDB to use any older
136 .gdb_index sections it finds. This will restore performance, but the
137 ability to set breakpoints on inlined functions will be lost in symbol
138 files with older .gdb_index sections.
140 The .gdb_index section has also been updated to record more information
141 about each symbol. This speeds up the "info variables", "info functions"
142 and "info types" commands when used with programs having the .gdb_index
143 section, as well as speeding up debugging with shared libraries using
144 the .gdb_index section.
146 * Ada support for GDB/MI Variable Objects has been added.
148 * GDB can now support 'breakpoint always-inserted mode' in 'record'
153 ** New command -info-os is the MI equivalent of "info os".
155 ** Output logs ("set logging" and related) now include MI output.
159 ** "set use-deprecated-index-sections on|off"
160 "show use-deprecated-index-sections on|off"
161 Controls the use of deprecated .gdb_index sections.
163 ** "catch load" and "catch unload" can be used to stop when a shared
164 library is loaded or unloaded, respectively.
166 ** "enable count" can be used to auto-disable a breakpoint after
169 ** "info vtbl" can be used to show the virtual method tables for
170 C++ and Java objects.
172 ** "explore" and its sub commands "explore value" and "explore type"
173 can be used to reccursively explore values and types of
174 expressions. These commands are available only if GDB is
175 configured with '--with-python'.
177 ** "info auto-load" shows status of all kinds of auto-loaded files,
178 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
179 sequences of commands files, "info auto-load python-scripts"
180 shows status of auto-loading Python script files,
181 "info auto-load local-gdbinit" shows status of loading init file
182 (.gdbinit) from current directory and "info auto-load libthread-db" shows
183 status of inferior specific thread debugging shared library loading.
185 ** "info auto-load-scripts", "set auto-load-scripts on|off"
186 and "show auto-load-scripts" commands have been deprecated, use their
187 "info auto-load python-scripts", "set auto-load python-scripts on|off"
188 and "show auto-load python-scripts" counterparts instead.
190 ** "dprintf location,format,args..." creates a dynamic printf, which
191 is basically a breakpoint that does a printf and immediately
192 resumes your program's execution, so it is like a printf that you
193 can insert dynamically at runtime instead of at compiletime.
195 ** "set print symbol"
197 Controls whether GDB attempts to display the symbol, if any,
198 corresponding to addresses it prints. This defaults to "on", but
199 you can set it to "off" to restore GDB's previous behavior.
201 * Deprecated commands
203 ** For the Renesas Super-H architecture, the "regs" command has been
204 deprecated, and "info all-registers" should be used instead.
208 Renesas RL78 rl78-*-elf
209 HP OpenVMS ia64 ia64-hp-openvms*
211 * GDBserver supports evaluation of breakpoint conditions. When
212 support is advertised by GDBserver, GDB may be told to send the
213 breakpoint conditions in bytecode form to GDBserver. GDBserver
214 will only report the breakpoint trigger to GDB when its condition
220 show mips compression
221 Select the compressed ISA encoding used in functions that have no symbol
222 information available. The encoding can be set to either of:
225 and is updated automatically from ELF file flags if available.
227 set breakpoint condition-evaluation
228 show breakpoint condition-evaluation
229 Control whether breakpoint conditions are evaluated by GDB ("host") or by
230 GDBserver ("target"). Default option "auto" chooses the most efficient
232 This option can improve debugger efficiency depending on the speed of the
236 Disable auto-loading globally.
239 Show auto-loading setting of all kinds of auto-loaded files.
241 set auto-load gdb-scripts on|off
242 show auto-load gdb-scripts
243 Control auto-loading of GDB canned sequences of commands files.
245 set auto-load python-scripts on|off
246 show auto-load python-scripts
247 Control auto-loading of Python script files.
249 set auto-load local-gdbinit on|off
250 show auto-load local-gdbinit
251 Control loading of init file (.gdbinit) from current directory.
253 set auto-load libthread-db on|off
254 show auto-load libthread-db
255 Control auto-loading of inferior specific thread debugging shared library.
257 set auto-load scripts-directory <dir1>[:<dir2>...]
258 show auto-load scripts-directory
259 Set a list of directories from which to load auto-loaded scripts.
260 Automatically loaded Python scripts and GDB scripts are located in one
261 of the directories listed by this option.
262 The delimiter (':' above) may differ according to the host platform.
264 set auto-load safe-path <dir1>[:<dir2>...]
265 show auto-load safe-path
266 Set a list of directories from which it is safe to auto-load files.
267 The delimiter (':' above) may differ according to the host platform.
269 set debug auto-load on|off
271 Control display of debugging info for auto-loading the files above.
273 set dprintf-style gdb|call|agent
275 Control the way in which a dynamic printf is performed; "gdb"
276 requests a GDB printf command, while "call" causes dprintf to call a
277 function in the inferior. "agent" requests that the target agent
278 (such as GDBserver) do the printing.
280 set dprintf-function <expr>
281 show dprintf-function
282 set dprintf-channel <expr>
284 Set the function and optional first argument to the call when using
285 the "call" style of dynamic printf.
287 set disconnected-dprintf on|off
288 show disconnected-dprintf
289 Control whether agent-style dynamic printfs continue to be in effect
290 after GDB disconnects.
292 * New configure options
295 Configure default value for the 'set auto-load scripts-directory'
296 setting above. It defaults to '$debugdir:$datadir/auto-load',
297 $debugdir representing global debugging info directories (available
298 via 'show debug-file-directory') and $datadir representing GDB's data
299 directory (available via 'show data-directory').
301 --with-auto-load-safe-path
302 Configure default value for the 'set auto-load safe-path' setting
303 above. It defaults to the --with-auto-load-dir setting.
305 --without-auto-load-safe-path
306 Set 'set auto-load safe-path' to '/', effectively disabling this
311 z0/z1 conditional breakpoints extension
313 The z0/z1 breakpoint insertion packets have been extended to carry
314 a list of conditional expressions over to the remote stub depending on the
315 condition evaluation mode. The use of this extension can be controlled
316 via the "set remote conditional-breakpoints-packet" command.
320 Specify the signals which the remote stub may pass to the debugged
321 program without GDB involvement.
323 * New command line options
325 --init-command=FILE, -ix Like --command, -x but execute it
326 before loading inferior.
327 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
328 execute it before loading inferior.
330 *** Changes in GDB 7.4
332 * GDB now handles ambiguous linespecs more consistently; the existing
333 FILE:LINE support has been expanded to other types of linespecs. A
334 breakpoint will now be set on all matching locations in all
335 inferiors, and locations will be added or removed according to
338 * GDB now allows you to skip uninteresting functions and files when
339 stepping with the "skip function" and "skip file" commands.
341 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
342 and "show remote hardware-watchpoint-length-limit". These allows to
343 set or show the maximum length limit (in bytes) of a remote
344 target hardware watchpoint.
346 This allows e.g. to use "unlimited" hardware watchpoints with the
347 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
348 watchpoints are slower than real hardware watchpoints but are
349 significantly faster than gdb software watchpoints.
353 ** The register_pretty_printer function in module gdb.printing now takes
354 an optional `replace' argument. If True, the new printer replaces any
357 ** The "maint set python print-stack on|off" command has been
358 deprecated and will be deleted in GDB 7.5.
359 A new command: "set python print-stack none|full|message" has
360 replaced it. Additionally, the default for "print-stack" is
361 now "message", which just prints the error message without
364 ** A prompt substitution hook (prompt_hook) is now available to the
367 ** A new Python module, gdb.prompt has been added to the GDB Python
368 modules library. This module provides functionality for
369 escape sequences in prompts (used by set/show
370 extended-prompt). These escape sequences are replaced by their
373 ** Python commands and convenience-functions located in
374 'data-directory'/python/gdb/command and
375 'data-directory'/python/gdb/function are now automatically loaded
378 ** Blocks now provide four new attributes. global_block and
379 static_block will return the global and static blocks
380 respectively. is_static and is_global are boolean attributes
381 that indicate if the block is one of those two types.
383 ** Symbols now provide the "type" attribute, the type of the symbol.
385 ** The "gdb.breakpoint" function has been deprecated in favor of
388 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
389 of a function. This class is based on the "finish" command
390 available in the CLI.
392 ** Type objects for struct and union types now allow access to
393 the fields using standard Python dictionary (mapping) methods.
394 For example, "some_type['myfield']" now works, as does
397 ** A new event "gdb.new_objfile" has been added, triggered by loading a
400 ** A new function, "deep_items" has been added to the gdb.types
401 module in the GDB Python modules library. This function returns
402 an iterator over the fields of a struct or union type. Unlike
403 the standard Python "iteritems" method, it will recursively traverse
404 any anonymous fields.
408 ** "*stopped" events can report several new "reason"s, such as
411 ** Breakpoint changes are now notified using new async records, like
412 "=breakpoint-modified".
414 ** New command -ada-task-info.
416 * libthread-db-search-path now supports two special values: $sdir and $pdir.
417 $sdir specifies the default system locations of shared libraries.
418 $pdir specifies the directory where the libpthread used by the application
421 GDB no longer looks in $sdir and $pdir after it has searched the directories
422 mentioned in libthread-db-search-path. If you want to search those
423 directories, they must be specified in libthread-db-search-path.
424 The default value of libthread-db-search-path on GNU/Linux and Solaris
425 systems is now "$sdir:$pdir".
427 $pdir is not supported by gdbserver, it is currently ignored.
428 $sdir is supported by gdbserver.
430 * New configure option --with-iconv-bin.
431 When using the internationalization support like the one in the GNU C
432 library, GDB will invoke the "iconv" program to get a list of supported
433 character sets. If this program lives in a non-standard location, one can
434 use this option to specify where to find it.
436 * When natively debugging programs on PowerPC BookE processors running
437 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
438 watchpoints, which specify a mask in addition to an address to watch.
439 The mask specifies that some bits of an address (the bits which are
440 reset in the mask) should be ignored when matching the address accessed
441 by the inferior against the watchpoint address. See the "PowerPC Embedded"
442 section in the user manual for more details.
444 * The new option --once causes GDBserver to stop listening for connections once
445 the first connection is made. The listening port used by GDBserver will
446 become available after that.
448 * New commands "info macros" and "alias" have been added.
450 * New function parameters suffix @entry specifies value of function parameter
451 at the time the function got called. Entry values are available only since
457 "!" is now an alias of the "shell" command.
458 Note that no space is needed between "!" and SHELL COMMAND.
462 watch EXPRESSION mask MASK_VALUE
463 The watch command now supports the mask argument which allows creation
464 of masked watchpoints, if the current architecture supports this feature.
466 info auto-load-scripts [REGEXP]
467 This command was formerly named "maintenance print section-scripts".
468 It is now generally useful and is no longer a maintenance-only command.
470 info macro [-all] [--] MACRO
471 The info macro command has new options `-all' and `--'. The first for
472 printing all definitions of a macro. The second for explicitly specifying
473 the end of arguments and the beginning of the macro name in case the macro
474 name starts with a hyphen.
476 collect[/s] EXPRESSIONS
477 The tracepoint collect command now takes an optional modifier "/s"
478 that directs it to dereference pointer-to-character types and
479 collect the bytes of memory up to a zero byte. The behavior is
480 similar to what you see when you use the regular print command on a
481 string. An optional integer following the "/s" sets a bound on the
482 number of bytes that will be collected.
485 The trace start command now interprets any supplied arguments as a
486 note to be recorded with the trace run, with an effect similar to
487 setting the variable trace-notes.
490 The trace stop command now interprets any arguments as a note to be
491 mentioned along with the tstatus report that the trace was stopped
492 with a command. The effect is similar to setting the variable
495 * Tracepoints can now be enabled and disabled at any time after a trace
496 experiment has been started using the standard "enable" and "disable"
497 commands. It is now possible to start a trace experiment with no enabled
498 tracepoints; GDB will display a warning, but will allow the experiment to
499 begin, assuming that tracepoints will be enabled as needed while the trace
502 * Fast tracepoints on 32-bit x86-architectures can now be placed at
503 locations with 4-byte instructions, when they were previously
504 limited to locations with instructions of 5 bytes or longer.
508 set debug dwarf2-read
509 show debug dwarf2-read
510 Turns on or off display of debugging messages related to reading
511 DWARF debug info. The default is off.
513 set debug symtab-create
514 show debug symtab-create
515 Turns on or off display of debugging messages related to symbol table
516 creation. The default is off.
520 Set the GDB prompt, and allow escape sequences to be inserted to
521 display miscellaneous information (see 'help set extended-prompt'
522 for the list of sequences). This prompt (and any information
523 accessed through the escape sequences) is updated every time the
526 set print entry-values (both|compact|default|if-needed|no|only|preferred)
527 show print entry-values
528 Set printing of frame argument values at function entry. In some cases
529 GDB can determine the value of function argument which was passed by the
530 function caller, even if the value was modified inside the called function.
532 set debug entry-values
533 show debug entry-values
534 Control display of debugging info for determining frame argument values at
535 function entry and virtual tail call frames.
537 set basenames-may-differ
538 show basenames-may-differ
539 Set whether a source file may have multiple base names.
540 (A "base name" is the name of a file with the directory part removed.
541 Example: The base name of "/home/user/hello.c" is "hello.c".)
542 If set, GDB will canonicalize file names (e.g., expand symlinks)
543 before comparing them. Canonicalization is an expensive operation,
544 but it allows the same file be known by more than one base name.
545 If not set (the default), all source files are assumed to have just
546 one base name, and gdb will do file name comparisons more efficiently.
552 Set a user name and notes for the current and any future trace runs.
553 This is useful for long-running and/or disconnected traces, to
554 inform others (or yourself) as to who is running the trace, supply
555 contact information, or otherwise explain what is going on.
558 show trace-stop-notes
559 Set a note attached to the trace run, that is displayed when the
560 trace has been stopped by a tstop command. This is useful for
561 instance as an explanation, if you are stopping a trace run that was
562 started by someone else.
568 Dynamically enable a tracepoint in a started trace experiment.
572 Dynamically disable a tracepoint in a started trace experiment.
576 Set the user and notes of the trace run.
580 Query the current status of a tracepoint.
584 Query the minimum length of instruction at which a fast tracepoint may
587 * Dcache size (number of lines) and line-size are now runtime-configurable
588 via "set dcache line" and "set dcache line-size" commands.
592 Texas Instruments TMS320C6x tic6x-*-*
596 Renesas RL78 rl78-*-elf
598 *** Changes in GDB 7.3.1
600 * The build failure for NetBSD and OpenBSD targets have now been fixed.
602 *** Changes in GDB 7.3
604 * GDB has a new command: "thread find [REGEXP]".
605 It finds the thread id whose name, target id, or thread extra info
606 matches the given regular expression.
608 * The "catch syscall" command now works on mips*-linux* targets.
610 * The -data-disassemble MI command now supports modes 2 and 3 for
611 dumping the instruction opcodes.
613 * New command line options
615 -data-directory DIR Specify DIR as the "data-directory".
616 This is mostly for testing purposes.
618 * The "maint set python auto-load on|off" command has been renamed to
619 "set auto-load-scripts on|off".
621 * GDB has a new command: "set directories".
622 It is like the "dir" command except that it replaces the
623 source path list instead of augmenting it.
625 * GDB now understands thread names.
627 On GNU/Linux, "info threads" will display the thread name as set by
628 prctl or pthread_setname_np.
630 There is also a new command, "thread name", which can be used to
631 assign a name internally for GDB to display.
634 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
635 has been integrated into GDB.
639 ** The function gdb.Write now accepts an optional keyword 'stream'.
640 This keyword, when provided, will direct the output to either
641 stdout, stderr, or GDB's logging output.
643 ** Parameters can now be be sub-classed in Python, and in particular
644 you may implement the get_set_doc and get_show_doc functions.
645 This improves how Parameter set/show documentation is processed
646 and allows for more dynamic content.
648 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
649 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
650 have an is_valid method.
652 ** Breakpoints can now be sub-classed in Python, and in particular
653 you may implement a 'stop' function that is executed each time
654 the inferior reaches that breakpoint.
656 ** New function gdb.lookup_global_symbol looks up a global symbol.
658 ** GDB values in Python are now callable if the value represents a
659 function. For example, if 'some_value' represents a function that
660 takes two integer parameters and returns a value, you can call
661 that function like so:
663 result = some_value (10,20)
665 ** Module gdb.types has been added.
666 It contains a collection of utilities for working with gdb.Types objects:
667 get_basic_type, has_field, make_enum_dict.
669 ** Module gdb.printing has been added.
670 It contains utilities for writing and registering pretty-printers.
671 New classes: PrettyPrinter, SubPrettyPrinter,
672 RegexpCollectionPrettyPrinter.
673 New function: register_pretty_printer.
675 ** New commands "info pretty-printers", "enable pretty-printer" and
676 "disable pretty-printer" have been added.
678 ** gdb.parameter("directories") is now available.
680 ** New function gdb.newest_frame returns the newest frame in the
683 ** The gdb.InferiorThread class has a new "name" attribute. This
684 holds the thread's name.
686 ** Python Support for Inferior events.
687 Python scripts can add observers to be notified of events
688 occurring in the process being debugged.
689 The following events are currently supported:
690 - gdb.events.cont Continue event.
691 - gdb.events.exited Inferior exited event.
692 - gdb.events.stop Signal received, and Breakpoint hit events.
696 ** GDB now puts template parameters in scope when debugging in an
697 instantiation. For example, if you have:
699 template<int X> int func (void) { return X; }
701 then if you step into func<5>, "print X" will show "5". This
702 feature requires proper debuginfo support from the compiler; it
703 was added to GCC 4.5.
705 ** The motion commands "next", "finish", "until", and "advance" now
706 work better when exceptions are thrown. In particular, GDB will
707 no longer lose control of the inferior; instead, the GDB will
708 stop the inferior at the point at which the exception is caught.
709 This functionality requires a change in the exception handling
710 code that was introduced in GCC 4.5.
712 * GDB now follows GCC's rules on accessing volatile objects when
713 reading or writing target state during expression evaluation.
714 One notable difference to prior behavior is that "print x = 0"
715 no longer generates a read of x; the value of the assignment is
716 now always taken directly from the value being assigned.
718 * GDB now has some support for using labels in the program's source in
719 linespecs. For instance, you can use "advance label" to continue
720 execution to a label.
722 * GDB now has support for reading and writing a new .gdb_index
723 section. This section holds a fast index of DWARF debugging
724 information and can be used to greatly speed up GDB startup and
725 operation. See the documentation for `save gdb-index' for details.
727 * The "watch" command now accepts an optional "-location" argument.
728 When used, this causes GDB to watch the memory referred to by the
729 expression. Such a watchpoint is never deleted due to it going out
732 * GDB now supports thread debugging of core dumps on GNU/Linux.
734 GDB now activates thread debugging using the libthread_db library
735 when debugging GNU/Linux core dumps, similarly to when debugging
736 live processes. As a result, when debugging a core dump file, GDB
737 is now able to display pthread_t ids of threads. For example, "info
738 threads" shows the same output as when debugging the process when it
739 was live. In earlier releases, you'd see something like this:
742 * 1 LWP 6780 main () at main.c:10
744 While now you see this:
747 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
749 It is also now possible to inspect TLS variables when debugging core
752 When debugging a core dump generated on a machine other than the one
753 used to run GDB, you may need to point GDB at the correct
754 libthread_db library with the "set libthread-db-search-path"
755 command. See the user manual for more details on this command.
757 * When natively debugging programs on PowerPC BookE processors running
758 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
759 which stop execution of the inferior whenever it executes an instruction
760 at any address within the specified range. See the "PowerPC Embedded"
761 section in the user manual for more details.
763 * New features in the GDB remote stub, GDBserver
765 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
766 and i686 LynxOS (version 5.x).
768 ** GDBserver is now supported on Blackfin Linux.
770 * New native configurations
772 ia64 HP-UX ia64-*-hpux*
776 Analog Devices, Inc. Blackfin Processor bfin-*
778 * Ada task switching is now supported on sparc-elf targets when
779 debugging a program using the Ravenscar Profile. For more information,
780 see the "Tasking Support when using the Ravenscar Profile" section
781 in the GDB user manual.
783 * Guile support was removed.
785 * New features in the GNU simulator
787 ** The --map-info flag lists all known core mappings.
789 ** CFI flashes may be simulated via the "cfi" device.
791 *** Changes in GDB 7.2
793 * Shared library support for remote targets by default
795 When GDB is configured for a generic, non-OS specific target, like
796 for example, --target=arm-eabi or one of the many *-*-elf targets,
797 GDB now queries remote stubs for loaded shared libraries using the
798 `qXfer:libraries:read' packet. Previously, shared library support
799 was always disabled for such configurations.
803 ** Argument Dependent Lookup (ADL)
805 In C++ ADL lookup directs function search to the namespaces of its
806 arguments even if the namespace has not been imported.
816 Here the compiler will search for `foo' in the namespace of 'b'
817 and find A::foo. GDB now supports this. This construct is commonly
818 used in the Standard Template Library for operators.
820 ** Improved User Defined Operator Support
822 In addition to member operators, GDB now supports lookup of operators
823 defined in a namespace and imported with a `using' directive, operators
824 defined in the global scope, operators imported implicitly from an
825 anonymous namespace, and the ADL operators mentioned in the previous
827 GDB now also supports proper overload resolution for all the previously
828 mentioned flavors of operators.
830 ** static const class members
832 Printing of static const class members that are initialized in the
833 class definition has been fixed.
835 * Windows Thread Information Block access.
837 On Windows targets, GDB now supports displaying the Windows Thread
838 Information Block (TIB) structure. This structure is visible either
839 by using the new command `info w32 thread-information-block' or, by
840 dereferencing the new convenience variable named `$_tlb', a
841 thread-specific pointer to the TIB. This feature is also supported
842 when remote debugging using GDBserver.
846 Static tracepoints are calls in the user program into a tracing
847 library. One such library is a port of the LTTng kernel tracer to
848 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
849 When debugging with GDBserver, GDB now supports combining the GDB
850 tracepoint machinery with such libraries. For example: the user can
851 use GDB to probe a static tracepoint marker (a call from the user
852 program into the tracing library) with the new "strace" command (see
853 "New commands" below). This creates a "static tracepoint" in the
854 breakpoint list, that can be manipulated with the same feature set
855 as fast and regular tracepoints. E.g., collect registers, local and
856 global variables, collect trace state variables, and define
857 tracepoint conditions. In addition, the user can collect extra
858 static tracepoint marker specific data, by collecting the new
859 $_sdata internal variable. When analyzing the trace buffer, you can
860 inspect $_sdata like any other variable available to GDB. For more
861 information, see the "Tracepoints" chapter in GDB user manual. New
862 remote packets have been defined to support static tracepoints, see
863 the "New remote packets" section below.
865 * Better reconstruction of tracepoints after disconnected tracing
867 GDB will attempt to download the original source form of tracepoint
868 definitions when starting a trace run, and then will upload these
869 upon reconnection to the target, resulting in a more accurate
870 reconstruction of the tracepoints that are in use on the target.
874 You can now exercise direct control over the ways that GDB can
875 affect your program. For instance, you can disallow the setting of
876 breakpoints, so that the program can run continuously (assuming
877 non-stop mode). In addition, the "observer" variable is available
878 to switch all of the different controls; in observer mode, GDB
879 cannot affect the target's behavior at all, which is useful for
880 tasks like diagnosing live systems in the field.
882 * The new convenience variable $_thread holds the number of the
889 Return the address of the Windows Thread Information Block of a given thread.
893 In response to several of the tracepoint packets, the target may now
894 also respond with a number of intermediate `qRelocInsn' request
895 packets before the final result packet, to have GDB handle
896 relocating an instruction to execute at a different address. This
897 is particularly useful for stubs that support fast tracepoints. GDB
898 reports support for this feature in the qSupported packet.
902 List static tracepoint markers in the target program.
906 List static tracepoint markers at a given address in the target
909 qXfer:statictrace:read
911 Read the static trace data collected (by a `collect $_sdata'
912 tracepoint action). The remote stub reports support for this packet
913 to gdb's qSupported query.
917 Send the current settings of GDB's permission flags.
921 Send part of the source (textual) form of a tracepoint definition,
922 which includes location, conditional, and action list.
924 * The source command now accepts a -s option to force searching for the
925 script in the source search path even if the script name specifies
928 * New features in the GDB remote stub, GDBserver
930 - GDBserver now support tracepoints (including fast tracepoints, and
931 static tracepoints). The feature is currently supported by the
932 i386-linux and amd64-linux builds. See the "Tracepoints support
933 in gdbserver" section in the manual for more information.
935 GDBserver JIT compiles the tracepoint's conditional agent
936 expression bytecode into native code whenever possible for low
937 overhead dynamic tracepoints conditionals. For such tracepoints,
938 an expression that examines program state is evaluated when the
939 tracepoint is reached, in order to determine whether to capture
940 trace data. If the condition is simple and false, processing the
941 tracepoint finishes very quickly and no data is gathered.
943 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
944 for static tracepoints support.
946 - GDBserver now supports x86_64 Windows 64-bit debugging.
948 * GDB now sends xmlRegisters= in qSupported packet to indicate that
949 it understands register description.
951 * The --batch flag now disables pagination and queries.
953 * X86 general purpose registers
955 GDB now supports reading/writing byte, word and double-word x86
956 general purpose registers directly. This means you can use, say,
957 $ah or $ax to refer, respectively, to the byte register AH and
958 16-bit word register AX that are actually portions of the 32-bit
959 register EAX or 64-bit register RAX.
961 * The `commands' command now accepts a range of breakpoints to modify.
962 A plain `commands' following a command that creates multiple
963 breakpoints affects all the breakpoints set by that command. This
964 applies to breakpoints set by `rbreak', and also applies when a
965 single `break' command creates multiple breakpoints (e.g.,
966 breakpoints on overloaded c++ functions).
968 * The `rbreak' command now accepts a filename specification as part of
969 its argument, limiting the functions selected by the regex to those
970 in the specified file.
972 * Support for remote debugging Windows and SymbianOS shared libraries
973 from Unix hosts has been improved. Non Windows GDB builds now can
974 understand target reported file names that follow MS-DOS based file
975 system semantics, such as file names that include drive letters and
976 use the backslash character as directory separator. This makes it
977 possible to transparently use the "set sysroot" and "set
978 solib-search-path" on Unix hosts to point as host copies of the
979 target's shared libraries. See the new command "set
980 target-file-system-kind" described below, and the "Commands to
981 specify files" section in the user manual for more information.
985 eval template, expressions...
986 Convert the values of one or more expressions under the control
987 of the string template to a command line, and call it.
989 set target-file-system-kind unix|dos-based|auto
990 show target-file-system-kind
991 Set or show the assumed file system kind for target reported file
994 save breakpoints <filename>
995 Save all current breakpoint definitions to a file suitable for use
996 in a later debugging session. To read the saved breakpoint
997 definitions, use the `source' command.
999 `save tracepoints' is a new alias for `save-tracepoints'. The latter
1002 info static-tracepoint-markers
1003 Display information about static tracepoint markers in the target.
1005 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
1006 Define a static tracepoint by probing a marker at the given
1007 function, line, address, or marker ID.
1011 Enable and disable observer mode.
1013 set may-write-registers on|off
1014 set may-write-memory on|off
1015 set may-insert-breakpoints on|off
1016 set may-insert-tracepoints on|off
1017 set may-insert-fast-tracepoints on|off
1018 set may-interrupt on|off
1019 Set individual permissions for GDB effects on the target. Note that
1020 some of these settings can have undesirable or surprising
1021 consequences, particularly when changed in the middle of a session.
1022 For instance, disabling the writing of memory can prevent
1023 breakpoints from being inserted, cause single-stepping to fail, or
1024 even crash your program, if you disable after breakpoints have been
1025 inserted. However, GDB should not crash.
1027 set record memory-query on|off
1028 show record memory-query
1029 Control whether to stop the inferior if memory changes caused
1030 by an instruction cannot be recorded.
1035 The disassemble command now supports "start,+length" form of two arguments.
1039 ** GDB now provides a new directory location, called the python directory,
1040 where Python scripts written for GDB can be installed. The location
1041 of that directory is <data-directory>/python, where <data-directory>
1042 is the GDB data directory. For more details, see section `Scripting
1043 GDB using Python' in the manual.
1045 ** The GDB Python API now has access to breakpoints, symbols, symbol
1046 tables, program spaces, inferiors, threads and frame's code blocks.
1047 Additionally, GDB Parameters can now be created from the API, and
1048 manipulated via set/show in the CLI.
1050 ** New functions gdb.target_charset, gdb.target_wide_charset,
1051 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1053 ** New exception gdb.GdbError.
1055 ** Pretty-printers are now also looked up in the current program space.
1057 ** Pretty-printers can now be individually enabled and disabled.
1059 ** GDB now looks for names of Python scripts to auto-load in a
1060 special section named `.debug_gdb_scripts', in addition to looking
1061 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1063 * Tracepoint actions were unified with breakpoint commands. In particular,
1064 there are no longer differences in "info break" output for breakpoints and
1065 tracepoints and the "commands" command can be used for both tracepoints and
1066 regular breakpoints.
1070 ARM Symbian arm*-*-symbianelf*
1072 * D language support.
1073 GDB now supports debugging programs written in the D programming
1076 * GDB now supports the extended ptrace interface for PowerPC which is
1077 available since Linux kernel version 2.6.34. This automatically enables
1078 any hardware breakpoints and additional hardware watchpoints available in
1079 the processor. The old ptrace interface exposes just one hardware
1080 watchpoint and no hardware breakpoints.
1082 * GDB is now able to use the Data Value Compare (DVC) register available on
1083 embedded PowerPC processors to implement in hardware simple watchpoint
1084 conditions of the form:
1086 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1088 This works in native GDB running on Linux kernels with the extended ptrace
1089 interface mentioned above.
1091 *** Changes in GDB 7.1
1095 ** Namespace Support
1097 GDB now supports importing of namespaces in C++. This enables the
1098 user to inspect variables from imported namespaces. Support for
1099 namepace aliasing has also been added. So, if a namespace is
1100 aliased in the current scope (e.g. namepace C=A; ) the user can
1101 print variables using the alias (e.g. (gdb) print C::x).
1105 All known bugs relating to the printing of virtual base class were
1106 fixed. It is now possible to call overloaded static methods using a
1111 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1112 and reinterpret_cast<> are now handled by the C++ expression parser.
1116 Xilinx MicroBlaze microblaze-*-*
1121 Xilinx MicroBlaze microblaze
1124 * Multi-program debugging.
1126 GDB now has support for multi-program (a.k.a. multi-executable or
1127 multi-exec) debugging. This allows for debugging multiple inferiors
1128 simultaneously each running a different program under the same GDB
1129 session. See "Debugging Multiple Inferiors and Programs" in the
1130 manual for more information. This implied some user visible changes
1131 in the multi-inferior support. For example, "info inferiors" now
1132 lists inferiors that are not running yet or that have exited
1133 already. See also "New commands" and "New options" below.
1135 * New tracing features
1137 GDB's tracepoint facility now includes several new features:
1139 ** Trace state variables
1141 GDB tracepoints now include support for trace state variables, which
1142 are variables managed by the target agent during a tracing
1143 experiment. They are useful for tracepoints that trigger each
1144 other, so for instance one tracepoint can count hits in a variable,
1145 and then a second tracepoint has a condition that is true when the
1146 count reaches a particular value. Trace state variables share the
1147 $-syntax of GDB convenience variables, and can appear in both
1148 tracepoint actions and condition expressions. Use the "tvariable"
1149 command to create, and "info tvariables" to view; see "Trace State
1150 Variables" in the manual for more detail.
1154 GDB now includes an option for defining fast tracepoints, which
1155 targets may implement more efficiently, such as by installing a jump
1156 into the target agent rather than a trap instruction. The resulting
1157 speedup can be by two orders of magnitude or more, although the
1158 tradeoff is that some program locations on some target architectures
1159 might not allow fast tracepoint installation, for instance if the
1160 instruction to be replaced is shorter than the jump. To request a
1161 fast tracepoint, use the "ftrace" command, with syntax identical to
1162 the regular trace command.
1164 ** Disconnected tracing
1166 It is now possible to detach GDB from the target while it is running
1167 a trace experiment, then reconnect later to see how the experiment
1168 is going. In addition, a new variable disconnected-tracing lets you
1169 tell the target agent whether to continue running a trace if the
1170 connection is lost unexpectedly.
1174 GDB now has the ability to save the trace buffer into a file, and
1175 then use that file as a target, similarly to you can do with
1176 corefiles. You can select trace frames, print data that was
1177 collected in them, and use tstatus to display the state of the
1178 tracing run at the moment that it was saved. To create a trace
1179 file, use "tsave <filename>", and to use it, do "target tfile
1182 ** Circular trace buffer
1184 You can ask the target agent to handle the trace buffer as a
1185 circular buffer, discarding the oldest trace frames to make room for
1186 newer ones, by setting circular-trace-buffer to on. This feature may
1187 not be available for all target agents.
1192 The disassemble command, when invoked with two arguments, now requires
1193 the arguments to be comma-separated.
1196 The info variables command now displays variable definitions. Files
1197 which only declare a variable are not shown.
1200 The source command is now capable of sourcing Python scripts.
1201 This feature is dependent on the debugger being build with Python
1204 Related to this enhancement is also the introduction of a new command
1205 "set script-extension" (see below).
1207 * New commands (for set/show, see "New options" below)
1209 record save [<FILENAME>]
1210 Save a file (in core file format) containing the process record
1211 execution log for replay debugging at a later time.
1213 record restore <FILENAME>
1214 Restore the process record execution log that was saved at an
1215 earlier time, for replay debugging.
1217 add-inferior [-copies <N>] [-exec <FILENAME>]
1220 clone-inferior [-copies <N>] [ID]
1221 Make a new inferior ready to execute the same program another
1222 inferior has loaded.
1227 maint info program-spaces
1228 List the program spaces loaded into GDB.
1230 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1231 show remote interrupt-sequence
1232 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1233 as the sequence to the remote target in order to interrupt the execution.
1234 Ctrl-C is a default. Some system prefers BREAK which is high level of
1235 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1236 Magic SysRq g. It is BREAK signal and character 'g'.
1238 set remote interrupt-on-connect [on | off]
1239 show remote interrupt-on-connect
1240 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1241 remote target when gdb connects to it. This is needed when you debug
1244 set remotebreak [on | off]
1246 Deprecated. Use "set/show remote interrupt-sequence" instead.
1248 tvariable $NAME [ = EXP ]
1249 Create or modify a trace state variable.
1252 List trace state variables and their values.
1254 delete tvariable $NAME ...
1255 Delete one or more trace state variables.
1258 Evaluate the given expressions without collecting anything into the
1259 trace buffer. (Valid in tracepoint actions only.)
1261 ftrace FN / FILE:LINE / *ADDR
1262 Define a fast tracepoint at the given function, line, or address.
1264 * New expression syntax
1266 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1267 GDB now parses 0b101010 identically with 42.
1271 set follow-exec-mode new|same
1272 show follow-exec-mode
1273 Control whether GDB reuses the same inferior across an exec call or
1274 creates a new one. This is useful to be able to restart the old
1275 executable after the inferior having done an exec call.
1277 set default-collect EXPR, ...
1278 show default-collect
1279 Define a list of expressions to be collected at each tracepoint.
1280 This is a useful way to ensure essential items are not overlooked,
1281 such as registers or a critical global variable.
1283 set disconnected-tracing
1284 show disconnected-tracing
1285 If set to 1, the target is instructed to continue tracing if it
1286 loses its connection to GDB. If 0, the target is to stop tracing
1289 set circular-trace-buffer
1290 show circular-trace-buffer
1291 If set to on, the target is instructed to use a circular trace buffer
1292 and discard the oldest trace frames instead of stopping the trace due
1293 to a full trace buffer. If set to off, the trace stops when the buffer
1294 fills up. Some targets may not support this.
1296 set script-extension off|soft|strict
1297 show script-extension
1298 If set to "off", the debugger does not perform any script language
1299 recognition, and all sourced files are assumed to be GDB scripts.
1300 If set to "soft" (the default), files are sourced according to
1301 filename extension, falling back to GDB scripts if the first
1303 If set to "strict", files are sourced according to filename extension.
1305 set ada trust-PAD-over-XVS on|off
1306 show ada trust-PAD-over-XVS
1307 If off, activate a workaround against a bug in the debugging information
1308 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1309 the GCC sources for more information about the GNAT encoding and
1310 PAD types in particular). It is always safe to set this option to
1311 off, but this introduces a slight performance penalty. The default
1314 * Python API Improvements
1316 ** GDB provides the new class gdb.LazyString. This is useful in
1317 some pretty-printing cases. The new method gdb.Value.lazy_string
1318 provides a simple way to create objects of this type.
1320 ** The fields returned by gdb.Type.fields now have an
1321 `is_base_class' attribute.
1323 ** The new method gdb.Type.range returns the range of an array type.
1325 ** The new method gdb.parse_and_eval can be used to parse and
1326 evaluate an expression.
1328 * New remote packets
1331 Define a trace state variable.
1334 Get the current value of a trace state variable.
1337 Set desired tracing behavior upon disconnection.
1340 Set the trace buffer to be linear or circular.
1343 Get data about the tracepoints currently in use.
1347 Process record now works correctly with hardware watchpoints.
1349 Multiple bug fixes have been made to the mips-irix port, making it
1350 much more reliable. In particular:
1351 - Debugging threaded applications is now possible again. Previously,
1352 GDB would hang while starting the program, or while waiting for
1353 the program to stop at a breakpoint.
1354 - Attaching to a running process no longer hangs.
1355 - An error occurring while loading a core file has been fixed.
1356 - Changing the value of the PC register now works again. This fixes
1357 problems observed when using the "jump" command, or when calling
1358 a function from GDB, or even when assigning a new value to $pc.
1359 - With the "finish" and "return" commands, the return value for functions
1360 returning a small array is now correctly printed.
1361 - It is now possible to break on shared library code which gets executed
1362 during a shared library init phase (code executed while executing
1363 their .init section). Previously, the breakpoint would have no effect.
1364 - GDB is now able to backtrace through the signal handler for
1365 non-threaded programs.
1367 PIE (Position Independent Executable) programs debugging is now supported.
1368 This includes debugging execution of PIC (Position Independent Code) shared
1369 libraries although for that, it should be possible to run such libraries as an
1372 *** Changes in GDB 7.0
1374 * GDB now has an interface for JIT compilation. Applications that
1375 dynamically generate code can create symbol files in memory and register
1376 them with GDB. For users, the feature should work transparently, and
1377 for JIT developers, the interface is documented in the GDB manual in the
1378 "JIT Compilation Interface" chapter.
1380 * Tracepoints may now be conditional. The syntax is as for
1381 breakpoints; either an "if" clause appended to the "trace" command,
1382 or the "condition" command is available. GDB sends the condition to
1383 the target for evaluation using the same bytecode format as is used
1384 for tracepoint actions.
1386 * The disassemble command now supports: an optional /r modifier, print the
1387 raw instructions in hex as well as in symbolic form, and an optional /m
1388 modifier to print mixed source+assembly.
1390 * Process record and replay
1392 In a architecture environment that supports ``process record and
1393 replay'', ``process record and replay'' target can record a log of
1394 the process execution, and replay it with both forward and reverse
1397 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1398 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1399 set execution-direction {forward|reverse}, for targets that support
1402 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1403 feature is available with a native GDB running on kernel version
1406 * GDB now has support for multi-byte and wide character sets on the
1407 target. Strings whose character type is wchar_t, char16_t, or
1408 char32_t are now correctly printed. GDB supports wide- and unicode-
1409 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1410 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1411 `printf'. This feature requires iconv to work properly; if your
1412 system does not have a working iconv, GDB can use GNU libiconv. See
1413 the installation instructions for more information.
1415 * GDB now supports automatic retrieval of shared library files from
1416 remote targets. To use this feature, specify a system root that begins
1417 with the `remote:' prefix, either via the `set sysroot' command or via
1418 the `--with-sysroot' configure-time option.
1420 * "info sharedlibrary" now takes an optional regex of libraries to show,
1421 and it now reports if a shared library has no debugging information.
1423 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1424 now complete on file names.
1426 * When completing in expressions, gdb will attempt to limit
1427 completions to allowable structure or union fields, where appropriate.
1428 For instance, consider:
1430 # struct example { int f1; double f2; };
1431 # struct example variable;
1434 If the user types TAB at the end of this command line, the available
1435 completions will be "f1" and "f2".
1437 * Inlined functions are now supported. They show up in backtraces, and
1438 the "step", "next", and "finish" commands handle them automatically.
1440 * GDB now supports the token-splicing (##) and stringification (#)
1441 operators when expanding macros. It also supports variable-arity
1444 * GDB now supports inspecting extra signal information, exported by
1445 the new $_siginfo convenience variable. The feature is currently
1446 implemented on linux ARM, i386 and amd64.
1448 * GDB can now display the VFP floating point registers and NEON vector
1449 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1450 can provide these registers (requires Linux 2.6.30 or later). Remote
1451 and simulator targets may also provide them.
1453 * New remote packets
1456 Search memory for a sequence of bytes.
1459 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1460 operation over reliable transport links. Use of this packet is
1461 controlled by the `set remote noack-packet' command.
1464 Kill the process with the specified process ID. Use this in preference
1465 to `k' when multiprocess protocol extensions are supported.
1468 Obtains additional operating system information
1472 Read or write additional signal information.
1474 * Removed remote protocol undocumented extension
1476 An undocumented extension to the remote protocol's `S' stop reply
1477 packet that permited the stub to pass a process id was removed.
1478 Remote servers should use the `T' stop reply packet instead.
1480 * GDB now supports multiple function calling conventions according to the
1481 DWARF-2 DW_AT_calling_convention function attribute.
1483 * The SH target utilizes the aforementioned change to distinguish between gcc
1484 and Renesas calling convention. It also adds the new CLI commands
1485 `set/show sh calling-convention'.
1487 * GDB can now read compressed debug sections, as produced by GNU gold
1488 with the --compress-debug-sections=zlib flag.
1490 * 64-bit core files are now supported on AIX.
1492 * Thread switching is now supported on Tru64.
1494 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1495 which will be allocated using malloc later in program execution.
1497 * The qXfer:libraries:read remote procotol packet now allows passing a
1498 list of section offsets.
1500 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1501 conditions handling signals delivered during attach or thread creation
1502 have also been fixed.
1504 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1505 From the user's standpoint, all unqualified instances of True and False
1506 are treated as the standard definitions, regardless of context.
1508 * GDB now parses C++ symbol and type names more flexibly. For
1511 template<typename T> class C { };
1514 GDB will now correctly handle all of:
1516 ptype C<char const *>
1517 ptype C<char const*>
1518 ptype C<const char *>
1519 ptype C<const char*>
1521 * New features in the GDB remote stub, gdbserver
1523 - The "--wrapper" command-line argument tells gdbserver to use a
1524 wrapper program to launch programs for debugging.
1526 - On PowerPC and S/390 targets, it is now possible to use a single
1527 gdbserver executable to debug both 32-bit and 64-bit programs.
1528 (This requires gdbserver itself to be built as a 64-bit executable.)
1530 - gdbserver uses the new noack protocol mode for TCP connections to
1531 reduce communications latency, if also supported and enabled in GDB.
1533 - Support for the sparc64-linux-gnu target is now included in
1536 - The amd64-linux build of gdbserver now supports debugging both
1537 32-bit and 64-bit programs.
1539 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1540 now support hardware watchpoints, and will use them automatically
1545 GDB now has support for scripting using Python. Whether this is
1546 available is determined at configure time.
1548 New GDB commands can now be written in Python.
1550 * Ada tasking support
1552 Ada tasks can now be inspected in GDB. The following commands have
1556 Print the list of Ada tasks.
1558 Print detailed information about task number N.
1560 Print the task number of the current task.
1562 Switch the context of debugging to task number N.
1564 * Support for user-defined prefixed commands. The "define" command can
1565 add new commands to existing prefixes, e.g. "target".
1567 * Multi-inferior, multi-process debugging.
1569 GDB now has generalized support for multi-inferior debugging. See
1570 "Debugging Multiple Inferiors" in the manual for more information.
1571 Although availability still depends on target support, the command
1572 set is more uniform now. The GNU/Linux specific multi-forks support
1573 has been migrated to this new framework. This implied some user
1574 visible changes; see "New commands" and also "Removed commands"
1577 * Target descriptions can now describe the target OS ABI. See the
1578 "Target Description Format" section in the user manual for more
1581 * Target descriptions can now describe "compatible" architectures
1582 to indicate that the target can execute applications for a different
1583 architecture in addition to those for the main target architecture.
1584 See the "Target Description Format" section in the user manual for
1587 * Multi-architecture debugging.
1589 GDB now includes general supports for debugging applications on
1590 hybrid systems that use more than one single processor architecture
1591 at the same time. Each such hybrid architecture still requires
1592 specific support to be added. The only hybrid architecture supported
1593 in this version of GDB is the Cell Broadband Engine.
1595 * GDB now supports integrated debugging of Cell/B.E. applications that
1596 use both the PPU and SPU architectures. To enable support for hybrid
1597 Cell/B.E. debugging, you need to configure GDB to support both the
1598 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1599 --enable-targets configure option.
1601 * Non-stop mode debugging.
1603 For some targets, GDB now supports an optional mode of operation in
1604 which you can examine stopped threads while other threads continue
1605 to execute freely. This is referred to as non-stop mode, with the
1606 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1607 section in the user manual for more information.
1609 To be able to support remote non-stop debugging, a remote stub needs
1610 to implement the non-stop mode remote protocol extensions, as
1611 described in the "Remote Non-Stop" section of the user manual. The
1612 GDB remote stub, gdbserver, has been adjusted to support these
1613 extensions on linux targets.
1615 * New commands (for set/show, see "New options" below)
1617 catch syscall [NAME(S) | NUMBER(S)]
1618 Catch system calls. Arguments, which should be names of system
1619 calls or their numbers, mean catch only those syscalls. Without
1620 arguments, every syscall will be caught. When the inferior issues
1621 any of the specified syscalls, GDB will stop and announce the system
1622 call, both when it is called and when its call returns. This
1623 feature is currently available with a native GDB running on the
1624 Linux Kernel, under the following architectures: x86, x86_64,
1625 PowerPC and PowerPC64.
1627 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1629 Search memory for a sequence of bytes.
1631 maint set python print-stack
1632 maint show python print-stack
1633 Show a stack trace when an error is encountered in a Python script.
1636 Invoke CODE by passing it to the Python interpreter.
1641 These allow macros to be defined, undefined, and listed
1645 Show operating system information about processes.
1648 List the inferiors currently under GDB's control.
1651 Switch focus to inferior number NUM.
1654 Detach from inferior number NUM.
1657 Kill inferior number NUM.
1661 set spu stop-on-load
1662 show spu stop-on-load
1663 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1665 set spu auto-flush-cache
1666 show spu auto-flush-cache
1667 Control whether to automatically flush the software-managed cache
1668 during Cell/B.E. debugging.
1670 set sh calling-convention
1671 show sh calling-convention
1672 Control the calling convention used when calling SH target functions.
1675 show debug timestamp
1676 Control display of timestamps with GDB debugging output.
1678 set disassemble-next-line
1679 show disassemble-next-line
1680 Control display of disassembled source lines or instructions when
1683 set remote noack-packet
1684 show remote noack-packet
1685 Set/show the use of remote protocol QStartNoAckMode packet. See above
1686 under "New remote packets."
1688 set remote query-attached-packet
1689 show remote query-attached-packet
1690 Control use of remote protocol `qAttached' (query-attached) packet.
1692 set remote read-siginfo-object
1693 show remote read-siginfo-object
1694 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1697 set remote write-siginfo-object
1698 show remote write-siginfo-object
1699 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1702 set remote reverse-continue
1703 show remote reverse-continue
1704 Control use of remote protocol 'bc' (reverse-continue) packet.
1706 set remote reverse-step
1707 show remote reverse-step
1708 Control use of remote protocol 'bs' (reverse-step) packet.
1710 set displaced-stepping
1711 show displaced-stepping
1712 Control displaced stepping mode. Displaced stepping is a way to
1713 single-step over breakpoints without removing them from the debuggee.
1714 Also known as "out-of-line single-stepping".
1717 show debug displaced
1718 Control display of debugging info for displaced stepping.
1720 maint set internal-error
1721 maint show internal-error
1722 Control what GDB does when an internal error is detected.
1724 maint set internal-warning
1725 maint show internal-warning
1726 Control what GDB does when an internal warning is detected.
1731 Use a wrapper program to launch programs for debugging.
1733 set multiple-symbols (all|ask|cancel)
1734 show multiple-symbols
1735 The value of this variable can be changed to adjust the debugger behavior
1736 when an expression or a breakpoint location contains an ambiguous symbol
1737 name (an overloaded function name, for instance).
1739 set breakpoint always-inserted
1740 show breakpoint always-inserted
1741 Keep breakpoints always inserted in the target, as opposed to inserting
1742 them when resuming the target, and removing them when the target stops.
1743 This option can improve debugger performance on slow remote targets.
1745 set arm fallback-mode (arm|thumb|auto)
1746 show arm fallback-mode
1747 set arm force-mode (arm|thumb|auto)
1749 These commands control how ARM GDB determines whether instructions
1750 are ARM or Thumb. The default for both settings is auto, which uses
1751 the current CPSR value for instructions without symbols; previous
1752 versions of GDB behaved as if "set arm fallback-mode arm".
1754 set disable-randomization
1755 show disable-randomization
1756 Standalone programs run with the virtual address space randomization enabled
1757 by default on some platforms. This option keeps the addresses stable across
1758 multiple debugging sessions.
1762 Control whether other threads are stopped or not when some thread hits
1767 Requests that asynchronous execution is enabled in the target, if available.
1768 In this case, it's possible to resume target in the background, and interact
1769 with GDB while the target is running. "show target-async" displays the
1770 current state of asynchronous execution of the target.
1772 set target-wide-charset
1773 show target-wide-charset
1774 The target-wide-charset is the name of the character set that GDB
1775 uses when printing characters whose type is wchar_t.
1777 set tcp auto-retry (on|off)
1779 set tcp connect-timeout
1780 show tcp connect-timeout
1781 These commands allow GDB to retry failed TCP connections to a remote stub
1782 with a specified timeout period; this is useful if the stub is launched
1783 in parallel with GDB but may not be ready to accept connections immediately.
1785 set libthread-db-search-path
1786 show libthread-db-search-path
1787 Control list of directories which GDB will search for appropriate
1790 set schedule-multiple (on|off)
1791 show schedule-multiple
1792 Allow GDB to resume all threads of all processes or only threads of
1793 the current process.
1797 Use more aggressive caching for accesses to the stack. This improves
1798 performance of remote debugging (particularly backtraces) without
1799 affecting correctness.
1801 set interactive-mode (on|off|auto)
1802 show interactive-mode
1803 Control whether GDB runs in interactive mode (on) or not (off).
1804 When in interactive mode, GDB waits for the user to answer all
1805 queries. Otherwise, GDB does not wait and assumes the default
1806 answer. When set to auto (the default), GDB determines which
1807 mode to use based on the stdin settings.
1812 For program forks, this is replaced by the new more generic `info
1813 inferiors' command. To list checkpoints, you can still use the
1814 `info checkpoints' command, which was an alias for the `info forks'
1818 Replaced by the new `inferior' command. To switch between
1819 checkpoints, you can still use the `restart' command, which was an
1820 alias for the `fork' command.
1823 This is removed, since some targets don't have a notion of
1824 processes. To switch between processes, you can still use the
1825 `inferior' command using GDB's own inferior number.
1828 For program forks, this is replaced by the new more generic `kill
1829 inferior' command. To delete a checkpoint, you can still use the
1830 `delete checkpoint' command, which was an alias for the `delete
1834 For program forks, this is replaced by the new more generic `detach
1835 inferior' command. To detach a checkpoint, you can still use the
1836 `detach checkpoint' command, which was an alias for the `detach
1839 * New native configurations
1841 x86/x86_64 Darwin i[34567]86-*-darwin*
1843 x86_64 MinGW x86_64-*-mingw*
1847 Lattice Mico32 lm32-*
1848 x86 DICOS i[34567]86-*-dicos*
1849 x86_64 DICOS x86_64-*-dicos*
1852 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1853 (mingw32ce) debugging.
1859 These commands were actually not implemented on any target.
1861 *** Changes in GDB 6.8
1863 * New native configurations
1865 NetBSD/hppa hppa*-*netbsd*
1866 Xtensa GNU/Linux xtensa*-*-linux*
1870 NetBSD/hppa hppa*-*-netbsd*
1871 Xtensa GNU/Lunux xtensa*-*-linux*
1873 * Change in command line behavior -- corefiles vs. process ids.
1875 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1876 attaching to process NUMBER fails, GDB no longer attempts to open a
1877 core file named NUMBER. Attaching to a program using the -c option
1878 is no longer supported. Instead, use the '-p' or '--pid' options.
1880 * GDB can now be built as a native debugger for debugging Windows x86
1881 (mingw32) Portable Executable (PE) programs.
1883 * Pending breakpoints no longer change their number when their address
1886 * GDB now supports breakpoints with multiple locations,
1887 including breakpoints on C++ constructors, inside C++ templates,
1888 and in inlined functions.
1890 * GDB's ability to debug optimized code has been improved. GDB more
1891 accurately identifies function bodies and lexical blocks that occupy
1892 more than one contiguous range of addresses.
1894 * Target descriptions can now describe registers for PowerPC.
1896 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1897 registers on PowerPC targets.
1899 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1900 targets even when the libthread_db library is not available.
1902 * The GDB remote stub, gdbserver, now supports the new file transfer
1903 commands (remote put, remote get, and remote delete).
1905 * The GDB remote stub, gdbserver, now supports run and attach in
1906 extended-remote mode.
1908 * hppa*64*-*-hpux11* target broken
1909 The debugger is unable to start a program and fails with the following
1910 error: "Error trying to get information about dynamic linker".
1911 The gdb-6.7 release is also affected.
1913 * GDB now supports the --enable-targets= configure option to allow
1914 building a single GDB executable that supports multiple remote
1915 target architectures.
1917 * GDB now supports debugging C and C++ programs which use the
1918 Decimal Floating Point extension. In addition, the PowerPC target
1919 now has a set of pseudo-registers to inspect decimal float values
1920 stored in two consecutive float registers.
1922 * The -break-insert MI command can optionally create pending
1925 * Improved support for debugging Ada
1926 Many improvements to the Ada language support have been made. These
1928 - Better support for Ada2005 interface types
1929 - Improved handling of arrays and slices in general
1930 - Better support for Taft-amendment types
1931 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1933 - Improved command completion in Ada
1936 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1941 set print frame-arguments (all|scalars|none)
1942 show print frame-arguments
1943 The value of this variable can be changed to control which argument
1944 values should be printed by the debugger when displaying a frame.
1949 Transfer files to and from a remote target, and delete remote files.
1956 Transfer files to and from a remote target, and delete remote files.
1958 * New remote packets
1965 Open, close, read, write, and delete files on the remote system.
1968 Attach to an existing process on the remote system, in extended-remote
1972 Run a new process on the remote system, in extended-remote mode.
1974 *** Changes in GDB 6.7
1976 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1977 bfd, libiberty and opcodes, as revealed by static analysis donated by
1978 Coverity, Inc. (http://scan.coverity.com).
1980 * When looking up multiply-defined global symbols, GDB will now prefer the
1981 symbol definition in the current shared library if it was built using the
1982 -Bsymbolic linker option.
1984 * When the Text User Interface (TUI) is not configured, GDB will now
1985 recognize the -tui command-line option and print a message that the TUI
1988 * The GDB remote stub, gdbserver, now has lower overhead for high
1989 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1991 * GDB for MIPS targets now autodetects whether a remote target provides
1992 32-bit or 64-bit register values.
1994 * Support for C++ member pointers has been improved.
1996 * GDB now understands XML target descriptions, which specify the
1997 target's overall architecture. GDB can read a description from
1998 a local file or over the remote serial protocol.
2000 * Vectors of single-byte data use a new integer type which is not
2001 automatically displayed as character or string data.
2003 * The /s format now works with the print command. It displays
2004 arrays of single-byte integers and pointers to single-byte integers
2007 * Target descriptions can now describe target-specific registers,
2008 for architectures which have implemented the support (currently
2009 only ARM, M68K, and MIPS).
2011 * GDB and the GDB remote stub, gdbserver, now support the XScale
2014 * The GDB remote stub, gdbserver, has been updated to support
2015 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2016 has been rewritten to use the standard GDB remote protocol.
2018 * GDB can now step into C++ functions which are called through thunks.
2020 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2022 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2023 layout. It also supports a TextSeg= and DataSeg= response when only
2024 segment base addresses (rather than offsets) are available.
2026 * The /i format now outputs any trailing branch delay slot instructions
2027 immediately following the last instruction within the count specified.
2029 * The GDB remote protocol "T" stop reply packet now supports a
2030 "library" response. Combined with the new "qXfer:libraries:read"
2031 packet, this response allows GDB to debug shared libraries on targets
2032 where the operating system manages the list of loaded libraries (e.g.
2033 Windows and SymbianOS).
2035 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2036 (DLLs) on Windows and Windows CE targets.
2038 * GDB now supports a faster verification that a .debug file matches its binary
2039 according to its build-id signature, if the signature is present.
2045 Enable or disable hardware flow control (RTS/CTS) on the serial port
2046 when debugging using remote targets.
2048 set mem inaccessible-by-default
2049 show mem inaccessible-by-default
2050 If the target supplies a memory map, for instance via the remote
2051 protocol's "qXfer:memory-map:read" packet, setting this variable
2052 prevents GDB from accessing memory outside the memory map. This
2053 is useful for targets with memory mapped registers or which react
2054 badly to accesses of unmapped address space.
2056 set breakpoint auto-hw
2057 show breakpoint auto-hw
2058 If the target supplies a memory map, for instance via the remote
2059 protocol's "qXfer:memory-map:read" packet, setting this variable
2060 lets GDB use hardware breakpoints automatically for memory regions
2061 where it can not use software breakpoints. This covers both the
2062 "break" command and internal breakpoints used for other commands
2063 including "next" and "finish".
2066 catch exception unhandled
2067 Stop the program execution when Ada exceptions are raised.
2070 Stop the program execution when an Ada assertion failed.
2074 Set an alternate system root for target files. This is a more
2075 general version of "set solib-absolute-prefix", which is now
2076 an alias to "set sysroot".
2079 Provide extended SPU facility status information. This set of
2080 commands is available only when debugging the Cell/B.E. SPU
2083 * New native configurations
2085 OpenBSD/sh sh*-*openbsd*
2088 unset tdesc filename
2090 Use the specified local file as an XML target description, and do
2091 not query the target for its built-in description.
2095 OpenBSD/sh sh*-*-openbsd*
2096 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2097 Toshiba Media Processor mep-elf
2099 * New remote packets
2102 Ignore the specified signals; pass them directly to the debugged program
2103 without stopping other threads or reporting them to GDB.
2105 qXfer:features:read:
2106 Read an XML target description from the target, which describes its
2111 Read or write contents of an spufs file on the target system. These
2112 packets are available only on the Cell/B.E. SPU architecture.
2114 qXfer:libraries:read:
2115 Report the loaded shared libraries. Combined with new "T" packet
2116 response, this packet allows GDB to debug shared libraries on
2117 targets where the operating system manages the list of loaded
2118 libraries (e.g. Windows and SymbianOS).
2122 Support for these obsolete configurations has been removed.
2130 i[34567]86-*-lynxos*
2131 i[34567]86-*-netware*
2132 i[34567]86-*-sco3.2v5*
2133 i[34567]86-*-sco3.2v4*
2135 i[34567]86-*-sysv4.2*
2138 i[34567]86-*-unixware2*
2139 i[34567]86-*-unixware*
2148 * Other removed features
2155 Various m68k-only ROM monitors.
2162 Various Renesas ROM monitors and debugging interfaces for SH and
2167 Support for a Macraigor serial interface to on-chip debugging.
2168 GDB does not directly support the newer parallel or USB
2173 A debug information format. The predecessor to DWARF 2 and
2174 DWARF 3, which are still supported.
2176 Support for the HP aCC compiler on HP-UX/PA-RISC
2178 SOM-encapsulated symbolic debugging information, automatic
2179 invocation of pxdb, and the aCC custom C++ ABI. This does not
2180 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2181 with aCC can still be debugged on an assembly level.
2183 MIPS ".pdr" sections
2185 A MIPS-specific format used to describe stack frame layout
2186 in debugging information.
2190 GDB could work with an older version of Guile to debug
2191 the interpreter and Scheme programs running in it.
2193 set mips stack-arg-size
2194 set mips saved-gpreg-size
2196 Use "set mips abi" to control parameter passing for MIPS.
2198 *** Changes in GDB 6.6
2203 Cell Broadband Engine SPU spu-elf
2205 * GDB can now be configured as a cross-debugger targeting native Windows
2206 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2207 running on a Windows system over TCP/IP to debug Windows programs.
2209 * The GDB remote stub, gdbserver, has been updated to support Windows and
2210 Cygwin debugging. Both single-threaded and multi-threaded programs are
2213 * The "set trust-readonly-sections" command works again. This command was
2214 broken in GDB 6.3, 6.4, and 6.5.
2216 * The "load" command now supports writing to flash memory, if the remote
2217 stub provides the required support.
2219 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2220 longer requires symbolic debug information (e.g. DWARF-2).
2225 unset substitute-path
2226 show substitute-path
2227 Manage a list of substitution rules that GDB uses to rewrite the name
2228 of the directories where the sources are located. This can be useful
2229 for instance when the sources were moved to a different location
2230 between compilation and debugging.
2234 Print each CLI command as it is executed. Each command is prefixed with
2235 a number of `+' symbols representing the nesting depth.
2236 The source command now has a `-v' option to enable the same feature.
2240 The ARM Demon monitor support (RDP protocol, "target rdp").
2242 Kernel Object Display, an embedded debugging feature which only worked with
2243 an obsolete version of Cisco IOS.
2245 The 'set download-write-size' and 'show download-write-size' commands.
2247 * New remote packets
2250 Tell a stub about GDB client features, and request remote target features.
2251 The first feature implemented is PacketSize, which allows the target to
2252 specify the size of packets it can handle - to minimize the number of
2253 packets required and improve performance when connected to a remote
2257 Fetch an OS auxilliary vector from the remote stub. This packet is a
2258 more efficient replacement for qPart:auxv:read.
2260 qXfer:memory-map:read:
2261 Fetch a memory map from the remote stub, including information about
2262 RAM, ROM, and flash memory devices.
2267 Erase and program a flash memory device.
2269 * Removed remote packets
2272 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2273 used it, and only gdbserver implemented it.
2275 *** Changes in GDB 6.5
2279 Renesas M32C/M16C m32c-elf
2281 Morpho Technologies ms1 ms1-elf
2285 init-if-undefined Initialize a convenience variable, but
2286 only if it doesn't already have a value.
2288 The following commands are presently only implemented for native GNU/Linux:
2290 checkpoint Save a snapshot of the program state.
2292 restart <n> Return the program state to a
2293 previously saved state.
2295 info checkpoints List currently saved checkpoints.
2297 delete-checkpoint <n> Delete a previously saved checkpoint.
2299 set|show detach-on-fork Tell gdb whether to detach from a newly
2300 forked process, or to keep debugging it.
2302 info forks List forks of the user program that
2303 are available to be debugged.
2305 fork <n> Switch to debugging one of several
2306 forks of the user program that are
2307 available to be debugged.
2309 delete-fork <n> Delete a fork from the list of forks
2310 that are available to be debugged (and
2311 kill the forked process).
2313 detach-fork <n> Delete a fork from the list of forks
2314 that are available to be debugged (and
2315 allow the process to continue).
2319 Morpho Technologies ms2 ms1-elf
2321 * Improved Windows host support
2323 GDB now builds as a cross debugger hosted on i686-mingw32, including
2324 native console support, and remote communications using either
2325 network sockets or serial ports.
2327 * Improved Modula-2 language support
2329 GDB can now print most types in the Modula-2 syntax. This includes:
2330 basic types, set types, record types, enumerated types, range types,
2331 pointer types and ARRAY types. Procedure var parameters are correctly
2332 printed and hexadecimal addresses and character constants are also
2333 written in the Modula-2 syntax. Best results can be obtained by using
2334 GNU Modula-2 together with the -gdwarf-2 command line option.
2338 The ARM rdi-share module.
2340 The Netware NLM debug server.
2342 *** Changes in GDB 6.4
2344 * New native configurations
2346 OpenBSD/arm arm*-*-openbsd*
2347 OpenBSD/mips64 mips64-*-openbsd*
2351 Morpho Technologies ms1 ms1-elf
2353 * New command line options
2355 --batch-silent As for --batch, but totally silent.
2356 --return-child-result The debugger will exist with the same value
2357 the child (debugged) program exited with.
2358 --eval-command COMMAND, -ex COMMAND
2359 Execute a single GDB CLI command. This may be
2360 specified multiple times and in conjunction
2361 with the --command (-x) option.
2363 * Deprecated commands removed
2365 The following commands, that were deprecated in 2000, have been
2369 set|show arm disassembly-flavor set|show arm disassembler
2370 othernames set arm disassembler
2371 set|show remotedebug set|show debug remote
2372 set|show archdebug set|show debug arch
2373 set|show eventdebug set|show debug event
2376 * New BSD user-level threads support
2378 It is now possible to debug programs using the user-level threads
2379 library on OpenBSD and FreeBSD. Currently supported (target)
2382 FreeBSD/amd64 x86_64-*-freebsd*
2383 FreeBSD/i386 i386-*-freebsd*
2384 OpenBSD/i386 i386-*-openbsd*
2386 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2387 are not yet supported.
2389 * New support for Matsushita MN10300 w/sim added
2390 (Work in progress). mn10300-elf.
2392 * REMOVED configurations and files
2394 VxWorks and the XDR protocol *-*-vxworks
2395 Motorola MCORE mcore-*-*
2396 National Semiconductor NS32000 ns32k-*-*
2398 * New "set print array-indexes" command
2400 After turning this setting "on", GDB prints the index of each element
2401 when displaying arrays. The default is "off" to preserve the previous
2404 * VAX floating point support
2406 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2408 * User-defined command support
2410 In addition to using $arg0..$arg9 for argument passing, it is now possible
2411 to use $argc to determine now many arguments have been passed. See the
2412 section on user-defined commands in the user manual for more information.
2414 *** Changes in GDB 6.3:
2416 * New command line option
2418 GDB now accepts -l followed by a number to set the timeout for remote
2421 * GDB works with GCC -feliminate-dwarf2-dups
2423 GDB now supports a more compact representation of DWARF-2 debug
2424 information using DW_FORM_ref_addr references. These are produced
2425 by GCC with the option -feliminate-dwarf2-dups and also by some
2426 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2427 to use -feliminate-dwarf2-dups.
2429 * Internationalization
2431 When supported by the host system, GDB will be built with
2432 internationalization (libintl). The task of marking up the sources is
2433 continued, we're looking forward to our first translation.
2437 Initial support for debugging programs compiled with the GNAT
2438 implementation of the Ada programming language has been integrated
2439 into GDB. In this release, support is limited to expression evaluation.
2441 * New native configurations
2443 GNU/Linux/m32r m32r-*-linux-gnu
2447 GDB's remote protocol now includes support for the 'p' packet. This
2448 packet is used to fetch individual registers from a remote inferior.
2450 * END-OF-LIFE registers[] compatibility module
2452 GDB's internal register infrastructure has been completely rewritten.
2453 The new infrastructure making possible the implementation of key new
2454 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2457 GDB 6.3 will be the last release to include the the registers[]
2458 compatibility module that allowed out-of-date configurations to
2459 continue to work. This change directly impacts the following
2469 powerpc bdm protocol
2471 Unless there is activity to revive these configurations, they will be
2472 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2474 * OBSOLETE configurations and files
2476 Configurations that have been declared obsolete in this release have
2477 been commented out. Unless there is activity to revive these
2478 configurations, the next release of GDB will have their sources
2479 permanently REMOVED.
2488 *** Changes in GDB 6.2.1:
2490 * MIPS `break main; run' gave an heuristic-fence-post warning
2492 When attempting to run even a simple program, a warning about
2493 heuristic-fence-post being hit would be reported. This problem has
2496 * MIPS IRIX 'long double' crashed GDB
2498 When examining a long double variable, GDB would get a segmentation
2499 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2500 IRIX long double values).
2504 A bug in the VAX stack code was causing problems with the "next"
2505 command. This problem has been fixed.
2507 *** Changes in GDB 6.2:
2509 * Fix for ``many threads''
2511 On GNU/Linux systems that use the NPTL threads library, a program
2512 rapidly creating and deleting threads would confuse GDB leading to the
2515 ptrace: No such process.
2516 thread_db_get_info: cannot get thread info: generic error
2518 This problem has been fixed.
2520 * "-async" and "-noasync" options removed.
2522 Support for the broken "-noasync" option has been removed (it caused
2525 * New ``start'' command.
2527 This command runs the program until the begining of the main procedure.
2529 * New BSD Kernel Data Access Library (libkvm) interface
2531 Using ``target kvm'' it is now possible to debug kernel core dumps and
2532 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2533 platforms. Currently supported (native-only) configurations are:
2535 FreeBSD/amd64 x86_64-*-freebsd*
2536 FreeBSD/i386 i?86-*-freebsd*
2537 NetBSD/i386 i?86-*-netbsd*
2538 NetBSD/m68k m68*-*-netbsd*
2539 NetBSD/sparc sparc-*-netbsd*
2540 OpenBSD/amd64 x86_64-*-openbsd*
2541 OpenBSD/i386 i?86-*-openbsd*
2542 OpenBSD/m68k m68*-openbsd*
2543 OpenBSD/sparc sparc-*-openbsd*
2545 * Signal trampoline code overhauled
2547 Many generic problems with GDB's signal handling code have been fixed.
2548 These include: backtraces through non-contiguous stacks; recognition
2549 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2550 call; backtrace through a signal trampoline; step into and out of
2551 signal handlers; and single-stepping in the signal trampoline.
2553 Please note that kernel bugs are a limiting factor here. These
2554 features have been shown to work on an s390 GNU/Linux system that
2555 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2557 * Cygwin support for DWARF 2 added.
2559 * New native configurations
2561 GNU/Linux/hppa hppa*-*-linux*
2562 OpenBSD/hppa hppa*-*-openbsd*
2563 OpenBSD/m68k m68*-*-openbsd*
2564 OpenBSD/m88k m88*-*-openbsd*
2565 OpenBSD/powerpc powerpc-*-openbsd*
2566 NetBSD/vax vax-*-netbsd*
2567 OpenBSD/vax vax-*-openbsd*
2569 * END-OF-LIFE frame compatibility module
2571 GDB's internal frame infrastructure has been completely rewritten.
2572 The new infrastructure making it possible to support key new features
2573 including DWARF 2 Call Frame Information. To aid in the task of
2574 migrating old configurations to this new infrastructure, a
2575 compatibility module, that allowed old configurations to continue to
2576 work, was also included.
2578 GDB 6.2 will be the last release to include this frame compatibility
2579 module. This change directly impacts the following configurations:
2589 Unless there is activity to revive these configurations, they will be
2590 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2592 * REMOVED configurations and files
2594 Sun 3, running SunOS 3 m68*-*-sunos3*
2595 Sun 3, running SunOS 4 m68*-*-sunos4*
2596 Sun 2, running SunOS 3 m68000-*-sunos3*
2597 Sun 2, running SunOS 4 m68000-*-sunos4*
2598 Motorola 680x0 running LynxOS m68*-*-lynxos*
2599 AT&T 3b1/Unix pc m68*-att-*
2600 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2601 decstation mips-dec-* mips-little-*
2602 riscos mips-*-riscos* mips-*-sysv*
2603 sonymips mips-sony-*
2604 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2606 *** Changes in GDB 6.1.1:
2608 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2610 The TUI (Text-mode User Interface) is now built as part of a default
2611 GDB configuration. It is enabled by either selecting the TUI with the
2612 command line option "-i=tui" or by running the separate "gdbtui"
2613 program. For more information on the TUI, see the manual "Debugging
2616 * Pending breakpoint support (also included in GDB 6.1)
2618 Support has been added to allow you to specify breakpoints in shared
2619 libraries that have not yet been loaded. If a breakpoint location
2620 cannot be found, and the "breakpoint pending" option is set to auto,
2621 GDB queries you if you wish to make the breakpoint pending on a future
2622 shared-library load. If and when GDB resolves the breakpoint symbol,
2623 the pending breakpoint is removed as one or more regular breakpoints
2626 Pending breakpoints are very useful for GCJ Java debugging.
2628 * Fixed ISO-C build problems
2630 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2631 non ISO-C code that stopped them being built using a more strict ISO-C
2632 compiler (e.g., IBM's C compiler).
2634 * Fixed build problem on IRIX 5
2636 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2637 wasn't able to compile compile on an IRIX 5 system.
2639 * Added execute permission to gdb/gdbserver/configure
2641 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2642 permission. This bug would cause configure to fail on a number of
2643 systems (Solaris, IRIX). Ref: server/519.
2645 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2647 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2648 has been updated to use constant array sizes.
2650 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2652 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2653 its generated DWARF Call Frame Info. This encoding was causing GDB to
2654 panic, that panic has been fixed. Ref: gdb/1628.
2656 * Fixed a problem when examining parameters in shared library code.
2658 When examining parameters in optimized shared library code generated
2659 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2660 not available''. GDB now correctly displays the variable's value.
2662 *** Changes in GDB 6.1:
2664 * Removed --with-mmalloc
2666 Support for the mmalloc memory manager has been removed, as it
2667 conflicted with the internal gdb byte cache.
2669 * Changes in AMD64 configurations
2671 The AMD64 target now includes the %cs and %ss registers. As a result
2672 the AMD64 remote protocol has changed; this affects the floating-point
2673 and SSE registers. If you rely on those registers for your debugging,
2674 you should upgrade gdbserver on the remote side.
2676 * Revised SPARC target
2678 The SPARC target has been completely revised, incorporating the
2679 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2680 support for LynxOS and SunOS 4 has been dropped. Calling functions
2681 from within GDB on operating systems with a non-executable stack
2682 (Solaris, OpenBSD) now works.
2686 GDB has a new C++ demangler which does a better job on the mangled
2687 names generated by current versions of g++. It also runs faster, so
2688 with this and other changes gdb should now start faster on large C++
2691 * DWARF 2 Location Expressions
2693 GDB support for location expressions has been extended to support function
2694 arguments and frame bases. Older versions of GDB could crash when they
2697 * C++ nested types and namespaces
2699 GDB's support for nested types and namespaces in C++ has been
2700 improved, especially if you use the DWARF 2 debugging format. (This
2701 is the default for recent versions of GCC on most platforms.)
2702 Specifically, if you have a class "Inner" defined within a class or
2703 namespace "Outer", then GDB realizes that the class's name is
2704 "Outer::Inner", not simply "Inner". This should greatly reduce the
2705 frequency of complaints about not finding RTTI symbols. In addition,
2706 if you are stopped at inside of a function defined within a namespace,
2707 GDB modifies its name lookup accordingly.
2709 * New native configurations
2711 NetBSD/amd64 x86_64-*-netbsd*
2712 OpenBSD/amd64 x86_64-*-openbsd*
2713 OpenBSD/alpha alpha*-*-openbsd*
2714 OpenBSD/sparc sparc-*-openbsd*
2715 OpenBSD/sparc64 sparc64-*-openbsd*
2717 * New debugging protocols
2719 M32R with SDI protocol m32r-*-elf*
2721 * "set prompt-escape-char" command deleted.
2723 The command "set prompt-escape-char" has been deleted. This command,
2724 and its very obscure effet on GDB's prompt, was never documented,
2725 tested, nor mentioned in the NEWS file.
2727 * OBSOLETE configurations and files
2729 Configurations that have been declared obsolete in this release have
2730 been commented out. Unless there is activity to revive these
2731 configurations, the next release of GDB will have their sources
2732 permanently REMOVED.
2734 Sun 3, running SunOS 3 m68*-*-sunos3*
2735 Sun 3, running SunOS 4 m68*-*-sunos4*
2736 Sun 2, running SunOS 3 m68000-*-sunos3*
2737 Sun 2, running SunOS 4 m68000-*-sunos4*
2738 Motorola 680x0 running LynxOS m68*-*-lynxos*
2739 AT&T 3b1/Unix pc m68*-att-*
2740 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2741 decstation mips-dec-* mips-little-*
2742 riscos mips-*-riscos* mips-*-sysv*
2743 sonymips mips-sony-*
2744 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2746 * REMOVED configurations and files
2748 SGI Irix-4.x mips-sgi-irix4 or iris4
2749 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2750 Z8000 simulator z8k-zilog-none or z8ksim
2751 Matsushita MN10200 w/simulator mn10200-*-*
2752 H8/500 simulator h8500-hitachi-hms or h8500hms
2753 HP/PA running BSD hppa*-*-bsd*
2754 HP/PA running OSF/1 hppa*-*-osf*
2755 HP/PA Pro target hppa*-*-pro*
2756 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2757 386BSD i[3456]86-*-bsd*
2758 Sequent family i[3456]86-sequent-sysv4*
2759 i[3456]86-sequent-sysv*
2760 i[3456]86-sequent-bsd*
2761 SPARC running LynxOS sparc-*-lynxos*
2762 SPARC running SunOS 4 sparc-*-sunos4*
2763 Tsqware Sparclet sparclet-*-*
2764 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2766 *** Changes in GDB 6.0:
2770 Support for debugging the Objective-C programming language has been
2771 integrated into GDB.
2773 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2775 DWARF 2's Call Frame Information makes available compiler generated
2776 information that more exactly describes the program's run-time stack.
2777 By using this information, GDB is able to provide more robust stack
2780 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2781 have been updated to use a new backtrace mechanism which includes
2782 DWARF 2 CFI support.
2786 GDB's remote protocol has been extended to include support for hosted
2787 file I/O (where the remote target uses GDB's file system). See GDB's
2788 remote protocol documentation for details.
2790 * All targets using the new architecture framework.
2792 All of GDB's targets have been updated to use the new internal
2793 architecture framework. The way is now open for future GDB releases
2794 to include cross-architecture native debugging support (i386 on amd64,
2797 * GNU/Linux's Thread Local Storage (TLS)
2799 GDB now includes support for for the GNU/Linux implementation of
2800 per-thread variables.
2802 * GNU/Linux's Native POSIX Thread Library (NPTL)
2804 GDB's thread code has been updated to work with either the new
2805 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2807 * Separate debug info.
2809 GDB, in conjunction with BINUTILS, now supports a mechanism for
2810 automatically loading debug information from a separate file. Instead
2811 of shipping full debug and non-debug versions of system libraries,
2812 system integrators can now instead ship just the stripped libraries
2813 and optional debug files.
2815 * DWARF 2 Location Expressions
2817 DWARF 2 Location Expressions allow the compiler to more completely
2818 describe the location of variables (even in optimized code) to the
2821 GDB now includes preliminary support for location expressions (support
2822 for DW_OP_piece is still missing).
2826 A number of long standing bugs that caused GDB to die while starting a
2827 Java application have been fixed. GDB's Java support is now
2828 considered "useable".
2830 * GNU/Linux support for fork, vfork, and exec.
2832 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2833 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2836 * GDB supports logging output to a file
2838 There are two new commands, "set logging" and "show logging", which can be
2839 used to capture GDB's output to a file.
2841 * The meaning of "detach" has changed for gdbserver
2843 The "detach" command will now resume the application, as documented. To
2844 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2847 * d10v, m68hc11 `regs' command deprecated
2849 The `info registers' command has been updated so that it displays the
2850 registers using a format identical to the old `regs' command.
2854 A new command, "maint set profile on/off", has been added. This command can
2855 be used to enable or disable profiling while running GDB, to profile a
2856 session or a set of commands. In addition there is a new configure switch,
2857 "--enable-profiling", which will cause GDB to be compiled with profiling
2858 data, for more informative profiling results.
2860 * Default MI syntax changed to "mi2".
2862 The default MI (machine interface) syntax, enabled by the command line
2863 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2864 "mi1", can be enabled by specifying the option "-i=mi1".
2866 Support for the original "mi0" syntax (included in GDB 5.0) has been
2869 Fix for gdb/192: removed extraneous space when displaying frame level.
2870 Fix for gdb/672: update changelist is now output in mi list format.
2871 Fix for gdb/702: a -var-assign that updates the value now shows up
2872 in a subsequent -var-update.
2874 * New native configurations.
2876 FreeBSD/amd64 x86_64-*-freebsd*
2878 * Multi-arched targets.
2880 HP/PA HPUX11 hppa*-*-hpux*
2881 Renesas M32R/D w/simulator m32r-*-elf*
2883 * OBSOLETE configurations and files
2885 Configurations that have been declared obsolete in this release have
2886 been commented out. Unless there is activity to revive these
2887 configurations, the next release of GDB will have their sources
2888 permanently REMOVED.
2890 Z8000 simulator z8k-zilog-none or z8ksim
2891 Matsushita MN10200 w/simulator mn10200-*-*
2892 H8/500 simulator h8500-hitachi-hms or h8500hms
2893 HP/PA running BSD hppa*-*-bsd*
2894 HP/PA running OSF/1 hppa*-*-osf*
2895 HP/PA Pro target hppa*-*-pro*
2896 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2897 Sequent family i[3456]86-sequent-sysv4*
2898 i[3456]86-sequent-sysv*
2899 i[3456]86-sequent-bsd*
2900 Tsqware Sparclet sparclet-*-*
2901 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2903 * REMOVED configurations and files
2906 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2907 IBM AIX PS/2 i[3456]86-*-aix
2908 i386 running Mach 3.0 i[3456]86-*-mach3*
2909 i386 running Mach i[3456]86-*-mach*
2910 i386 running OSF/1 i[3456]86-*osf1mk*
2911 HP/Apollo 68k Family m68*-apollo*-sysv*,
2913 m68*-hp-bsd*, m68*-hp-hpux*
2914 Argonaut Risc Chip (ARC) arc-*-*
2915 Mitsubishi D30V d30v-*-*
2916 Fujitsu FR30 fr30-*-elf*
2917 OS/9000 i[34]86-*-os9k
2918 I960 with MON960 i960-*-coff
2920 * MIPS $fp behavior changed
2922 The convenience variable $fp, for the MIPS, now consistently returns
2923 the address of the current frame's base. Previously, depending on the
2924 context, $fp could refer to either $sp or the current frame's base
2925 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2926 The GNU Source-Level Debugger''.
2928 *** Changes in GDB 5.3:
2930 * GNU/Linux shared library multi-threaded performance improved.
2932 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2933 `/proc', in preference to `ptrace' for memory reads. This may result
2934 in an improvement in the start-up time of multi-threaded, shared
2935 library applications when run under GDB. One GDB user writes: ``loads
2936 shared libs like mad''.
2938 * ``gdbserver'' now supports multi-threaded applications on some targets
2940 Support for debugging multi-threaded applications which use
2941 the GNU/Linux LinuxThreads package has been added for
2942 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2943 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2945 * GDB now supports C/C++ preprocessor macros.
2947 GDB now expands preprocessor macro invocations in C/C++ expressions,
2948 and provides various commands for showing macro definitions and how
2951 The new command `macro expand EXPRESSION' expands any macro
2952 invocations in expression, and shows the result.
2954 The new command `show macro MACRO-NAME' shows the definition of the
2955 macro named MACRO-NAME, and where it was defined.
2957 Most compilers don't include information about macros in the debugging
2958 information by default. In GCC 3.1, for example, you need to compile
2959 your program with the options `-gdwarf-2 -g3'. If the macro
2960 information is present in the executable, GDB will read it.
2962 * Multi-arched targets.
2964 DEC Alpha (partial) alpha*-*-*
2965 DEC VAX (partial) vax-*-*
2967 National Semiconductor NS32000 (partial) ns32k-*-*
2968 Motorola 68000 (partial) m68k-*-*
2969 Motorola MCORE mcore-*-*
2973 Fujitsu FRV architecture added by Red Hat frv*-*-*
2976 * New native configurations
2978 Alpha NetBSD alpha*-*-netbsd*
2979 SH NetBSD sh*-*-netbsdelf*
2980 MIPS NetBSD mips*-*-netbsd*
2981 UltraSPARC NetBSD sparc64-*-netbsd*
2983 * OBSOLETE configurations and files
2985 Configurations that have been declared obsolete in this release have
2986 been commented out. Unless there is activity to revive these
2987 configurations, the next release of GDB will have their sources
2988 permanently REMOVED.
2990 Mitsubishi D30V d30v-*-*
2991 OS/9000 i[34]86-*-os9k
2992 IBM AIX PS/2 i[3456]86-*-aix
2993 Fujitsu FR30 fr30-*-elf*
2994 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2995 Argonaut Risc Chip (ARC) arc-*-*
2996 i386 running Mach 3.0 i[3456]86-*-mach3*
2997 i386 running Mach i[3456]86-*-mach*
2998 i386 running OSF/1 i[3456]86-*osf1mk*
2999 HP/Apollo 68k Family m68*-apollo*-sysv*,
3001 m68*-hp-bsd*, m68*-hp-hpux*
3002 I960 with MON960 i960-*-coff
3004 * OBSOLETE languages
3006 CHILL, a Pascal like language used by telecommunications companies.
3008 * REMOVED configurations and files
3010 AMD 29k family via UDI a29k-amd-udi, udi29k
3011 A29K VxWorks a29k-*-vxworks
3012 AMD 29000 embedded, using EBMON a29k-none-none
3013 AMD 29000 embedded with COFF a29k-none-coff
3014 AMD 29000 embedded with a.out a29k-none-aout
3016 testsuite/gdb.hp/gdb.threads-hp/ directory
3018 * New command "set max-user-call-depth <nnn>"
3020 This command allows the user to limit the call depth of user-defined
3021 commands. The default is 1024.
3023 * Changes in FreeBSD/i386 native debugging.
3025 Support for the "generate-core-file" has been added.
3027 * New commands "dump", "append", and "restore".
3029 These commands allow data to be copied from target memory
3030 to a bfd-format or binary file (dump and append), and back
3031 from a file into memory (restore).
3033 * Improved "next/step" support on multi-processor Alpha Tru64.
3035 The previous single-step mechanism could cause unpredictable problems,
3036 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3037 of a software single-step mechanism prevents this.
3039 *** Changes in GDB 5.2.1:
3047 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3048 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3049 Fix, by Joel Brobecker imported from mainline.
3051 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3052 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3053 Fix, by Fred Fish, imported from mainline.
3055 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3056 Surprisingly enough, it works now.
3057 By Michal Ludvig, imported from mainline.
3059 i386 hardware watchpoint support:
3060 avoid misses on second run for some targets.
3061 By Pierre Muller, imported from mainline.
3063 *** Changes in GDB 5.2:
3065 * New command "set trust-readonly-sections on[off]".
3067 This command is a hint that tells gdb that read-only sections
3068 really are read-only (ie. that their contents will not change).
3069 In this mode, gdb will go to the object file rather than the
3070 target to read memory from read-only sections (such as ".text").
3071 This can be a significant performance improvement on some
3072 (notably embedded) targets.
3074 * New command "generate-core-file" (or "gcore").
3076 This new gdb command allows the user to drop a core file of the child
3077 process state at any time. So far it's been implemented only for
3078 GNU/Linux and Solaris, but should be relatively easily ported to other
3079 hosts. Argument is core file name (defaults to core.<pid>).
3081 * New command line option
3083 GDB now accepts --pid or -p followed by a process id.
3085 * Change in command line behavior -- corefiles vs. process ids.
3087 There is a subtle behavior in the way in which GDB handles
3088 command line arguments. The first non-flag argument is always
3089 a program to debug, but the second non-flag argument may either
3090 be a corefile or a process id. Previously, GDB would attempt to
3091 open the second argument as a corefile, and if that failed, would
3092 issue a superfluous error message and then attempt to attach it as
3093 a process. Now, if the second argument begins with a non-digit,
3094 it will be treated as a corefile. If it begins with a digit,
3095 GDB will attempt to attach it as a process, and if no such process
3096 is found, will then attempt to open it as a corefile.
3098 * Changes in ARM configurations.
3100 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3101 configuration is fully multi-arch.
3103 * New native configurations
3105 ARM NetBSD arm*-*-netbsd*
3106 x86 OpenBSD i[3456]86-*-openbsd*
3107 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3108 Sparc64 running FreeBSD sparc64-*-freebsd*
3112 Sanyo XStormy16 xstormy16-elf
3114 * OBSOLETE configurations and files
3116 Configurations that have been declared obsolete in this release have
3117 been commented out. Unless there is activity to revive these
3118 configurations, the next release of GDB will have their sources
3119 permanently REMOVED.
3121 AMD 29k family via UDI a29k-amd-udi, udi29k
3122 A29K VxWorks a29k-*-vxworks
3123 AMD 29000 embedded, using EBMON a29k-none-none
3124 AMD 29000 embedded with COFF a29k-none-coff
3125 AMD 29000 embedded with a.out a29k-none-aout
3127 testsuite/gdb.hp/gdb.threads-hp/ directory
3129 * REMOVED configurations and files
3131 TI TMS320C80 tic80-*-*
3133 PowerPC Solaris powerpcle-*-solaris*
3134 PowerPC Windows NT powerpcle-*-cygwin32
3135 PowerPC Netware powerpc-*-netware*
3136 Harris/CXUX m88k m88*-harris-cxux*
3137 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3138 ns32k-utek-sysv* ns32k-utek-*
3139 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3140 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3141 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3142 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3143 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3145 * Changes to command line processing
3147 The new `--args' feature can be used to specify command-line arguments
3148 for the inferior from gdb's command line.
3150 * Changes to key bindings
3152 There is a new `operate-and-get-next' function bound to `C-o'.
3154 *** Changes in GDB 5.1.1
3156 Fix compile problem on DJGPP.
3158 Fix a problem with floating-point registers on the i386 being
3161 Fix to stop GDB crashing on .debug_str debug info.
3163 Numerous documentation fixes.
3165 Numerous testsuite fixes.
3167 *** Changes in GDB 5.1:
3169 * New native configurations
3171 Alpha FreeBSD alpha*-*-freebsd*
3172 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3173 MIPS GNU/Linux mips*-*-linux*
3174 MIPS SGI Irix 6.x mips*-sgi-irix6*
3175 ia64 AIX ia64-*-aix*
3176 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3180 Motorola 68HC11 and 68HC12 m68hc11-elf
3182 UltraSparc running GNU/Linux sparc64-*-linux*
3184 * OBSOLETE configurations and files
3186 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3187 Harris/CXUX m88k m88*-harris-cxux*
3188 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3189 ns32k-utek-sysv* ns32k-utek-*
3190 TI TMS320C80 tic80-*-*
3192 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3193 PowerPC Solaris powerpcle-*-solaris*
3194 PowerPC Windows NT powerpcle-*-cygwin32
3195 PowerPC Netware powerpc-*-netware*
3196 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3197 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3198 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3199 Apple Macintosh (MPW) host N/A
3201 stuff.c (Program to stuff files into a specially prepared space in kdb)
3202 kdb-start.c (Main loop for the standalone kernel debugger)
3204 Configurations that have been declared obsolete in this release have
3205 been commented out. Unless there is activity to revive these
3206 configurations, the next release of GDB will have their sources
3207 permanently REMOVED.
3209 * REMOVED configurations and files
3211 Altos 3068 m68*-altos-*
3212 Convex c1-*-*, c2-*-*
3214 ARM RISCix arm-*-* (as host)
3218 * GDB has been converted to ISO C.
3220 GDB's source code has been converted to ISO C. In particular, the
3221 sources are fully protoized, and rely on standard headers being
3226 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3228 * The MI enabled by default.
3230 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3231 revised and enabled by default. Packages which use GDB as a debugging
3232 engine behind a UI or another front end are encouraged to switch to
3233 using the GDB/MI interface, instead of the old annotations interface
3234 which is now deprecated.
3236 * Support for debugging Pascal programs.
3238 GDB now includes support for debugging Pascal programs. The following
3239 main features are supported:
3241 - Pascal-specific data types such as sets;
3243 - automatic recognition of Pascal sources based on file-name
3246 - Pascal-style display of data types, variables, and functions;
3248 - a Pascal expression parser.
3250 However, some important features are not yet supported.
3252 - Pascal string operations are not supported at all;
3254 - there are some problems with boolean types;
3256 - Pascal type hexadecimal constants are not supported
3257 because they conflict with the internal variables format;
3259 - support for Pascal objects and classes is not full yet;
3261 - unlike Pascal, GDB is case-sensitive for symbol names.
3263 * Changes in completion.
3265 Commands such as `shell', `run' and `set args', which pass arguments
3266 to inferior programs, now complete on file names, similar to what
3267 users expect at the shell prompt.
3269 Commands which accept locations, such as `disassemble', `print',
3270 `breakpoint', `until', etc. now complete on filenames as well as
3271 program symbols. Thus, if you type "break foob TAB", and the source
3272 files linked into the programs include `foobar.c', that file name will
3273 be one of the candidates for completion. However, file names are not
3274 considered for completion after you typed a colon that delimits a file
3275 name from a name of a function in that file, as in "break foo.c:bar".
3277 `set demangle-style' completes on available demangling styles.
3279 * New platform-independent commands:
3281 It is now possible to define a post-hook for a command as well as a
3282 hook that runs before the command. For more details, see the
3283 documentation of `hookpost' in the GDB manual.
3285 * Changes in GNU/Linux native debugging.
3287 Support for debugging multi-threaded programs has been completely
3288 revised for all platforms except m68k and sparc. You can now debug as
3289 many threads as your system allows you to have.
3291 Attach/detach is supported for multi-threaded programs.
3293 Support for SSE registers was added for x86. This doesn't work for
3294 multi-threaded programs though.
3296 * Changes in MIPS configurations.
3298 Multi-arch support is enabled for all MIPS configurations.
3300 GDB can now be built as native debugger on SGI Irix 6.x systems for
3301 debugging n32 executables. (Debugging 64-bit executables is not yet
3304 * Unified support for hardware watchpoints in all x86 configurations.
3306 Most (if not all) native x86 configurations support hardware-assisted
3307 breakpoints and watchpoints in a unified manner. This support
3308 implements debug register sharing between watchpoints, which allows to
3309 put a virtually infinite number of watchpoints on the same address,
3310 and also supports watching regions up to 16 bytes with several debug
3313 The new maintenance command `maintenance show-debug-regs' toggles
3314 debugging print-outs in functions that insert, remove, and test
3315 watchpoints and hardware breakpoints.
3317 * Changes in the DJGPP native configuration.
3319 New command ``info dos sysinfo'' displays assorted information about
3320 the CPU, OS, memory, and DPMI server.
3322 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3323 display information about segment descriptors stored in GDT, LDT, and
3326 New commands ``info dos pde'' and ``info dos pte'' display entries
3327 from Page Directory and Page Tables (for now works with CWSDPMI only).
3328 New command ``info dos address-pte'' displays the Page Table entry for
3329 a given linear address.
3331 GDB can now pass command lines longer than 126 characters to the
3332 program being debugged (requires an update to the libdbg.a library
3333 which is part of the DJGPP development kit).
3335 DWARF2 debug info is now supported.
3337 It is now possible to `step' and `next' through calls to `longjmp'.
3339 * Changes in documentation.
3341 All GDB documentation was converted to GFDL, the GNU Free
3342 Documentation License.
3344 Tracepoints-related commands are now fully documented in the GDB
3347 TUI, the Text-mode User Interface, is now documented in the manual.
3349 Tracepoints-related commands are now fully documented in the GDB
3352 The "GDB Internals" manual now has an index. It also includes
3353 documentation of `ui_out' functions, GDB coding standards, x86
3354 hardware watchpoints, and memory region attributes.
3356 * GDB's version number moved to ``version.in''
3358 The Makefile variable VERSION has been replaced by the file
3359 ``version.in''. People creating GDB distributions should update the
3360 contents of this file.
3364 GUD support is now a standard part of the EMACS distribution.
3366 *** Changes in GDB 5.0:
3368 * Improved support for debugging FP programs on x86 targets
3370 Unified and much-improved support for debugging floating-point
3371 programs on all x86 targets. In particular, ``info float'' now
3372 displays the FP registers in the same format on all x86 targets, with
3373 greater level of detail.
3375 * Improvements and bugfixes in hardware-assisted watchpoints
3377 It is now possible to watch array elements, struct members, and
3378 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3379 on x86 targets no longer erroneously trigger when the address is
3382 * Improvements in the native DJGPP version of GDB
3384 The distribution now includes all the scripts and auxiliary files
3385 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3386 machines ``out of the box''.
3388 The DJGPP version can now debug programs that use signals. It is
3389 possible to catch signals that happened in the debuggee, deliver
3390 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3391 would kill the program being debugged.) Programs that hook hardware
3392 interrupts (keyboard, timer, etc.) can also be debugged.
3394 It is now possible to debug DJGPP programs that redirect their
3395 standard handles or switch them to raw (as opposed to cooked) mode, or
3396 even close them. The command ``run < foo > bar'' works as expected,
3397 and ``info terminal'' reports useful information about the debuggee's
3398 terminal, including raw/cooked mode, redirection, etc.
3400 The DJGPP version now uses termios functions for console I/O, which
3401 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3404 DOS-style file names with drive letters are now fully supported by
3407 It is now possible to debug DJGPP programs that switch their working
3408 directory. It is also possible to rerun the debuggee any number of
3409 times without restarting GDB; thus, you can use the same setup,
3410 breakpoints, etc. for many debugging sessions.
3412 * New native configurations
3414 ARM GNU/Linux arm*-*-linux*
3415 PowerPC GNU/Linux powerpc-*-linux*
3419 Motorola MCore mcore-*-*
3420 x86 VxWorks i[3456]86-*-vxworks*
3421 PowerPC VxWorks powerpc-*-vxworks*
3422 TI TMS320C80 tic80-*-*
3424 * OBSOLETE configurations
3426 Altos 3068 m68*-altos-*
3427 Convex c1-*-*, c2-*-*
3429 ARM RISCix arm-*-* (as host)
3432 Configurations that have been declared obsolete will be commented out,
3433 but the code will be left in place. If there is no activity to revive
3434 these configurations before the next release of GDB, the sources will
3435 be permanently REMOVED.
3437 * Gould support removed
3439 Support for the Gould PowerNode and NP1 has been removed.
3441 * New features for SVR4
3443 On SVR4 native platforms (such as Solaris), if you attach to a process
3444 without first loading a symbol file, GDB will now attempt to locate and
3445 load symbols from the running process's executable file.
3447 * Many C++ enhancements
3449 C++ support has been greatly improved. Overload resolution now works properly
3450 in almost all cases. RTTI support is on the way.
3452 * Remote targets can connect to a sub-program
3454 A popen(3) style serial-device has been added. This device starts a
3455 sub-process (such as a stand-alone simulator) and then communicates
3456 with that. The sub-program to run is specified using the syntax
3457 ``|<program> <args>'' vis:
3459 (gdb) set remotedebug 1
3460 (gdb) target extended-remote |mn10300-elf-sim program-args
3462 * MIPS 64 remote protocol
3464 A long standing bug in the mips64 remote protocol where by GDB
3465 expected certain 32 bit registers (ex SR) to be transfered as 32
3466 instead of 64 bits has been fixed.
3468 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3469 added to provide backward compatibility with older versions of GDB.
3471 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3473 The command ``set remotebinarydownload'' command has been replaced by
3474 ``set remote X-packet''. Other commands in ``set remote'' family
3475 include ``set remote P-packet''.
3477 * Breakpoint commands accept ranges.
3479 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3480 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3481 ``tracepoint passcount'' also accepts a range of tracepoints.
3483 * ``apropos'' command added.
3485 The ``apropos'' command searches through command names and
3486 documentation strings, printing out matches, making it much easier to
3487 try to find a command that does what you are looking for.
3491 A new machine oriented interface (MI) has been added to GDB. This
3492 interface is designed for debug environments running GDB as a separate
3493 process. This is part of the long term libGDB project. See the
3494 "GDB/MI" chapter of the GDB manual for further information. It can be
3495 enabled by configuring with:
3497 .../configure --enable-gdbmi
3499 *** Changes in GDB-4.18:
3501 * New native configurations
3503 HP-UX 10.20 hppa*-*-hpux10.20
3504 HP-UX 11.x hppa*-*-hpux11.0*
3505 M68K GNU/Linux m68*-*-linux*
3509 Fujitsu FR30 fr30-*-elf*
3510 Intel StrongARM strongarm-*-*
3511 Mitsubishi D30V d30v-*-*
3513 * OBSOLETE configurations
3515 Gould PowerNode, NP1 np1-*-*, pn-*-*
3517 Configurations that have been declared obsolete will be commented out,
3518 but the code will be left in place. If there is no activity to revive
3519 these configurations before the next release of GDB, the sources will
3520 be permanently REMOVED.
3524 As a compatibility experiment, GDB's source files buildsym.h and
3525 buildsym.c have been converted to pure standard C, no longer
3526 containing any K&R compatibility code. We believe that all systems in
3527 use today either come with a standard C compiler, or have a GCC port
3528 available. If this is not true, please report the affected
3529 configuration to bug-gdb@gnu.org immediately. See the README file for
3530 information about getting a standard C compiler if you don't have one
3535 GDB now uses readline 2.2.
3537 * set extension-language
3539 You can now control the mapping between filename extensions and source
3540 languages by using the `set extension-language' command. For instance,
3541 you can ask GDB to treat .c files as C++ by saying
3542 set extension-language .c c++
3543 The command `info extensions' lists all of the recognized extensions
3544 and their associated languages.
3546 * Setting processor type for PowerPC and RS/6000
3548 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3549 you can use the `set processor' command to specify what variant of the
3550 PowerPC family you are debugging. The command
3554 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3555 following PowerPC and RS6000 variants:
3557 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3558 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3560 403GC IBM PowerPC 403GC
3561 505 Motorola PowerPC 505
3562 860 Motorola PowerPC 860 or 850
3563 601 Motorola PowerPC 601
3564 602 Motorola PowerPC 602
3565 603 Motorola/IBM PowerPC 603 or 603e
3566 604 Motorola PowerPC 604 or 604e
3567 750 Motorola/IBM PowerPC 750 or 750
3569 At the moment, this command just tells GDB what to name the
3570 special-purpose processor registers. Since almost all the affected
3571 registers are inaccessible to user-level programs, this command is
3572 only useful for remote debugging in its present form.
3576 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3577 more extensive support for HP-UX. Added features include shared
3578 library support, kernel threads and hardware watchpoints for 11.00,
3579 support for HP's ANSI C and C++ compilers, and a compatibility mode
3580 for xdb and dbx commands.
3584 HP's donation includes the new concept of catchpoints, which is a
3585 generalization of the old catch command. On HP-UX, it is now possible
3586 to catch exec, fork, and vfork, as well as library loading.
3588 This means that the existing catch command has changed; its first
3589 argument now specifies the type of catch to be set up. See the
3590 output of "help catch" for a list of catchpoint types.
3592 * Debugging across forks
3594 On HP-UX, you can choose which process to debug when a fork() happens
3599 HP has donated a curses-based terminal user interface (TUI). To get
3600 it, build with --enable-tui. Although this can be enabled for any
3601 configuration, at present it only works for native HP debugging.
3603 * GDB remote protocol additions
3605 A new protocol packet 'X' that writes binary data is now available.
3606 Default behavior is to try 'X', then drop back to 'M' if the stub
3607 fails to respond. The settable variable `remotebinarydownload'
3608 allows explicit control over the use of 'X'.
3610 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3611 full 64-bit address. The command
3613 set remoteaddresssize 32
3615 can be used to revert to the old behaviour. For existing remote stubs
3616 the change should not be noticed, as the additional address information
3619 In order to assist in debugging stubs, you may use the maintenance
3620 command `packet' to send any text string to the stub. For instance,
3622 maint packet heythere
3624 sends the packet "$heythere#<checksum>". Note that it is very easy to
3625 disrupt a debugging session by sending the wrong packet at the wrong
3628 The compare-sections command allows you to compare section data on the
3629 target to what is in the executable file without uploading or
3630 downloading, by comparing CRC checksums.
3632 * Tracing can collect general expressions
3634 You may now collect general expressions at tracepoints. This requires
3635 further additions to the target-side stub; see tracepoint.c and
3636 doc/agentexpr.texi for further details.
3638 * mask-address variable for Mips
3640 For Mips targets, you may control the zeroing of the upper 32 bits of
3641 a 64-bit address by entering `set mask-address on'. This is mainly
3642 of interest to users of embedded R4xxx and R5xxx processors.
3644 * Higher serial baud rates
3646 GDB's serial code now allows you to specify baud rates 57600, 115200,
3647 230400, and 460800 baud. (Note that your host system may not be able
3648 to achieve all of these rates.)
3652 The i960 configuration now includes an initial implementation of a
3653 builtin simulator, contributed by Jim Wilson.
3656 *** Changes in GDB-4.17:
3658 * New native configurations
3660 Alpha GNU/Linux alpha*-*-linux*
3661 Unixware 2.x i[3456]86-unixware2*
3662 Irix 6.x mips*-sgi-irix6*
3663 PowerPC GNU/Linux powerpc-*-linux*
3664 PowerPC Solaris powerpcle-*-solaris*
3665 Sparc GNU/Linux sparc-*-linux*
3666 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3670 Argonaut Risc Chip (ARC) arc-*-*
3671 Hitachi H8/300S h8300*-*-*
3672 Matsushita MN10200 w/simulator mn10200-*-*
3673 Matsushita MN10300 w/simulator mn10300-*-*
3674 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3675 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3676 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3677 Mitsubishi D10V w/simulator d10v-*-*
3678 Mitsubishi M32R/D w/simulator m32r-*-elf*
3679 Tsqware Sparclet sparclet-*-*
3680 NEC V850 w/simulator v850-*-*
3682 * New debugging protocols
3684 ARM with RDI protocol arm*-*-*
3685 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3686 DDB and LSI variants of PMON protocol mips*-*-*
3687 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3688 PowerPC with SDS protocol powerpc{,le}-*-eabi
3689 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3693 All configurations can now understand and use the DWARF 2 debugging
3694 format. The choice is automatic, if the symbol file contains DWARF 2
3699 GDB now includes basic Java language support. This support is
3700 only useful with Java compilers that produce native machine code.
3702 * solib-absolute-prefix and solib-search-path
3704 For SunOS and SVR4 shared libraries, you may now set the prefix for
3705 loading absolute shared library symbol files, and the search path for
3706 locating non-absolute shared library symbol files.
3708 * Live range splitting
3710 GDB can now effectively debug code for which GCC has performed live
3711 range splitting as part of its optimization. See gdb/doc/LRS for
3712 more details on the expected format of the stabs information.
3716 GDB's support for the GNU Hurd, including thread debugging, has been
3717 updated to work with current versions of the Hurd.
3721 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3722 instruction set. ARM GDB automatically detects when Thumb
3723 instructions are in use, and adjusts disassembly and backtracing
3728 GDB's MIPS target configurations now handle the MIP16 16-bit
3733 GDB now includes support for overlays; if an executable has been
3734 linked such that multiple sections are based at the same address, GDB
3735 will decide which section to use for symbolic info. You can choose to
3736 control the decision manually, using overlay commands, or implement
3737 additional target-side support and use "overlay load-target" to bring
3738 in the overlay mapping. Do "help overlay" for more detail.
3742 The command "info symbol <address>" displays information about
3743 the symbol at the specified address.
3747 The standard remote protocol now includes an extension that allows
3748 asynchronous collection and display of trace data. This requires
3749 extensive support in the target-side debugging stub. Tracing mode
3750 includes a new interaction mode in GDB and new commands: see the
3751 file tracepoint.c for more details.
3755 Configurations for embedded MIPS now include a simulator contributed
3756 by Cygnus Solutions. The simulator supports the instruction sets
3757 of most MIPS variants.
3761 Sparc configurations may now include the ERC32 simulator contributed
3762 by the European Space Agency. The simulator is not built into
3763 Sparc targets by default; configure with --enable-sim to include it.
3767 For target configurations that may include multiple variants of a
3768 basic architecture (such as MIPS and SH), you may now set the
3769 architecture explicitly. "set arch" sets, "info arch" lists
3770 the possible architectures.
3772 *** Changes in GDB-4.16:
3774 * New native configurations
3776 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3777 M68K NetBSD m68k-*-netbsd*
3778 PowerPC AIX 4.x powerpc-*-aix*
3779 PowerPC MacOS powerpc-*-macos*
3780 PowerPC Windows NT powerpcle-*-cygwin32
3781 RS/6000 AIX 4.x rs6000-*-aix4*
3785 ARM with RDP protocol arm-*-*
3786 I960 with MON960 i960-*-coff
3787 MIPS VxWorks mips*-*-vxworks*
3788 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3789 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3791 Matra Sparclet sparclet-*-*
3795 The powerpc-eabi configuration now includes the PSIM simulator,
3796 contributed by Andrew Cagney, with assistance from Mike Meissner.
3797 PSIM is a very elaborate model of the PowerPC, including not only
3798 basic instruction set execution, but also details of execution unit
3799 performance and I/O hardware. See sim/ppc/README for more details.
3803 GDB now works with Solaris 2.5.
3805 * Windows 95/NT native
3807 GDB will now work as a native debugger on Windows 95 and Windows NT.
3808 To build it from source, you must use the "gnu-win32" environment,
3809 which uses a DLL to emulate enough of Unix to run the GNU tools.
3810 Further information, binaries, and sources are available at
3811 ftp.cygnus.com, under pub/gnu-win32.
3813 * dont-repeat command
3815 If a user-defined command includes the command `dont-repeat', then the
3816 command will not be repeated if the user just types return. This is
3817 useful if the command is time-consuming to run, so that accidental
3818 extra keystrokes don't run the same command many times.
3820 * Send break instead of ^C
3822 The standard remote protocol now includes an option to send a break
3823 rather than a ^C to the target in order to interrupt it. By default,
3824 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3826 * Remote protocol timeout
3828 The standard remote protocol includes a new variable `remotetimeout'
3829 that allows you to set the number of seconds before GDB gives up trying
3830 to read from the target. The default value is 2.
3832 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3834 By default GDB will automatically keep track of objects as they are
3835 loaded and unloaded by the dynamic linker. By using the command `set
3836 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3837 when shared library events occur, thus allowing you to set breakpoints
3838 in shared libraries which are explicitly loaded by the inferior.
3840 Note this feature does not work on hpux8. On hpux9 you must link
3841 /usr/lib/end.o into your program. This feature should work
3842 automatically on hpux10.
3844 * Irix 5.x hardware watchpoint support
3846 Irix 5 configurations now support the use of hardware watchpoints.
3848 * Mips protocol "SYN garbage limit"
3850 When debugging a Mips target using the `target mips' protocol, you
3851 may set the number of characters that GDB will ignore by setting
3852 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3853 every character. The default value is 1050.
3855 * Recording and replaying remote debug sessions
3857 If you set `remotelogfile' to the name of a file, gdb will write to it
3858 a recording of a remote debug session. This recording may then be
3859 replayed back to gdb using "gdbreplay". See gdbserver/README for
3860 details. This is useful when you have a problem with GDB while doing
3861 remote debugging; you can make a recording of the session and send it
3862 to someone else, who can then recreate the problem.
3864 * Speedups for remote debugging
3866 GDB includes speedups for downloading and stepping MIPS systems using
3867 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3868 and more efficient S-record downloading.
3870 * Memory use reductions and statistics collection
3872 GDB now uses less memory and reports statistics about memory usage.
3873 Try the `maint print statistics' command, for example.
3875 *** Changes in GDB-4.15:
3877 * Psymtabs for XCOFF
3879 The symbol reader for AIX GDB now uses partial symbol tables. This
3880 can greatly improve startup time, especially for large executables.
3882 * Remote targets use caching
3884 Remote targets now use a data cache to speed up communication with the
3885 remote side. The data cache could lead to incorrect results because
3886 it doesn't know about volatile variables, thus making it impossible to
3887 debug targets which use memory mapped I/O devices. `set remotecache
3888 off' turns the the data cache off.
3890 * Remote targets may have threads
3892 The standard remote protocol now includes support for multiple threads
3893 in the target system, using new protocol commands 'H' and 'T'. See
3894 gdb/remote.c for details.
3898 If GDB is configured with `--enable-netrom', then it will include
3899 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3900 acts as though it is a bank of ROM on the target board, but you can
3901 write into it over the network. GDB's support consists only of
3902 support for fast loading into the emulated ROM; to debug, you must use
3903 another protocol, such as standard remote protocol. The usual
3904 sequence is something like
3906 target nrom <netrom-hostname>
3908 target remote <netrom-hostname>:1235
3912 GDB now includes support for the Apple Macintosh, as a host only. It
3913 may be run as either an MPW tool or as a standalone application, and
3914 it can debug through the serial port. All the usual GDB commands are
3915 available, but to the target command, you must supply "serial" as the
3916 device type instead of "/dev/ttyXX". See mpw-README in the main
3917 directory for more information on how to build. The MPW configuration
3918 scripts */mpw-config.in support only a few targets, and only the
3919 mips-idt-ecoff target has been tested.
3923 GDB configuration now uses autoconf. This is not user-visible,
3924 but does simplify configuration and building.
3928 GDB now supports hpux10.
3930 *** Changes in GDB-4.14:
3932 * New native configurations
3934 x86 FreeBSD i[345]86-*-freebsd
3935 x86 NetBSD i[345]86-*-netbsd
3936 NS32k NetBSD ns32k-*-netbsd
3937 Sparc NetBSD sparc-*-netbsd
3941 A29K VxWorks a29k-*-vxworks
3942 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3943 CPU32 EST-300 emulator m68*-*-est*
3944 PowerPC ELF powerpc-*-elf
3947 * Alpha OSF/1 support for procfs
3949 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3950 possible to attach to running processes. As the mounting of the /proc
3951 filesystem is optional on the Alpha, GDB automatically determines
3952 the availability of /proc during startup. This can lead to problems
3953 if /proc is unmounted after GDB has been started.
3955 * Arguments to user-defined commands
3957 User commands may accept up to 10 arguments separated by whitespace.
3958 Arguments are accessed within the user command via $arg0..$arg9. A
3961 print $arg0 + $arg1 + $arg2
3963 To execute the command use:
3966 Defines the command "adder" which prints the sum of its three arguments.
3967 Note the arguments are text substitutions, so they may reference variables,
3968 use complex expressions, or even perform inferior function calls.
3970 * New `if' and `while' commands
3972 This makes it possible to write more sophisticated user-defined
3973 commands. Both commands take a single argument, which is the
3974 expression to evaluate, and must be followed by the commands to
3975 execute, one per line, if the expression is nonzero, the list being
3976 terminated by the word `end'. The `if' command list may include an
3977 `else' word, which causes the following commands to be executed only
3978 if the expression is zero.
3980 * Fortran source language mode
3982 GDB now includes partial support for Fortran 77. It will recognize
3983 Fortran programs and can evaluate a subset of Fortran expressions, but
3984 variables and functions may not be handled correctly. GDB will work
3985 with G77, but does not yet know much about symbols emitted by other
3988 * Better HPUX support
3990 Most debugging facilities now work on dynamic executables for HPPAs
3991 running hpux9 or later. You can attach to running dynamically linked
3992 processes, but by default the dynamic libraries will be read-only, so
3993 for instance you won't be able to put breakpoints in them. To change
3994 that behavior do the following before running the program:
4000 This will cause the libraries to be mapped private and read-write.
4001 To revert to the normal behavior, do this:
4007 You cannot set breakpoints or examine data in the library until after
4008 the library is loaded if the function/data symbols do not have
4011 GDB can now also read debug symbols produced by the HP C compiler on
4012 HPPAs (sorry, no C++, Fortran or 68k support).
4014 * Target byte order now dynamically selectable
4016 You can choose which byte order to use with a target system, via the
4017 commands "set endian big" and "set endian little", and you can see the
4018 current setting by using "show endian". You can also give the command
4019 "set endian auto", in which case GDB will use the byte order
4020 associated with the executable. Currently, only embedded MIPS
4021 configurations support dynamic selection of target byte order.
4023 * New DOS host serial code
4025 This version uses DPMI interrupts to handle buffered I/O, so you
4026 no longer need to run asynctsr when debugging boards connected to
4029 *** Changes in GDB-4.13:
4031 * New "complete" command
4033 This lists all the possible completions for the rest of the line, if it
4034 were to be given as a command itself. This is intended for use by emacs.
4036 * Trailing space optional in prompt
4038 "set prompt" no longer adds a space for you after the prompt you set. This
4039 allows you to set a prompt which ends in a space or one that does not.
4041 * Breakpoint hit counts
4043 "info break" now displays a count of the number of times the breakpoint
4044 has been hit. This is especially useful in conjunction with "ignore"; you
4045 can ignore a large number of breakpoint hits, look at the breakpoint info
4046 to see how many times the breakpoint was hit, then run again, ignoring one
4047 less than that number, and this will get you quickly to the last hit of
4050 * Ability to stop printing at NULL character
4052 "set print null-stop" will cause GDB to stop printing the characters of
4053 an array when the first NULL is encountered. This is useful when large
4054 arrays actually contain only short strings.
4056 * Shared library breakpoints
4058 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4059 breakpoints in shared libraries before the executable is run.
4061 * Hardware watchpoints
4063 There is a new hardware breakpoint for the watch command for sparclite
4064 targets. See gdb/sparclite/hw_breakpoint.note.
4066 Hardware watchpoints are also now supported under GNU/Linux.
4070 Annotations have been added. These are for use with graphical interfaces,
4071 and are still experimental. Currently only gdba.el uses these.
4073 * Improved Irix 5 support
4075 GDB now works properly with Irix 5.2.
4077 * Improved HPPA support
4079 GDB now works properly with the latest GCC and GAS.
4081 * New native configurations
4083 Sequent PTX4 i[34]86-sequent-ptx4
4084 HPPA running OSF/1 hppa*-*-osf*
4085 Atari TT running SVR4 m68*-*-sysv4*
4086 RS/6000 LynxOS rs6000-*-lynxos*
4090 OS/9000 i[34]86-*-os9k
4091 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4094 * Hitachi SH7000 and E7000-PC ICE support
4096 There is now support for communicating with the Hitachi E7000-PC ICE.
4097 This is available automatically when GDB is configured for the SH.
4101 As usual, a variety of small fixes and improvements, both generic
4102 and configuration-specific. See the ChangeLog for more detail.
4104 *** Changes in GDB-4.12:
4106 * Irix 5 is now supported
4110 GDB-4.12 on the HPPA has a number of changes which make it unable
4111 to debug the output from the currently released versions of GCC and
4112 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4113 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4114 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4117 *** Changes in GDB-4.11:
4119 * User visible changes:
4123 The "set remotedebug" option is now consistent between the mips remote
4124 target, remote targets using the gdb-specific protocol, UDI (AMD's
4125 debug protocol for the 29k) and the 88k bug monitor. It is now an
4126 integer specifying a debug level (normally 0 or 1, but 2 means more
4127 debugging info for the mips target).
4129 * DEC Alpha native support
4131 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4132 debug info, but GDB works fairly well with the DEC compiler and should
4133 work with a future GCC release. See the README file for a few
4134 Alpha-specific notes.
4136 * Preliminary thread implementation
4138 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4140 * LynxOS native and target support for 386
4142 This release has been hosted on LynxOS 2.2, and also can be configured
4143 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4146 * Improvements in C++ mangling/demangling.
4148 This release has much better g++ debugging, specifically in name
4149 mangling/demangling, virtual function calls, print virtual table,
4150 call methods, ...etc.
4152 *** Changes in GDB-4.10:
4154 * User visible changes:
4156 Remote debugging using the GDB-specific (`target remote') protocol now
4157 supports the `load' command. This is only useful if you have some
4158 other way of getting the stub to the target system, and you can put it
4159 somewhere in memory where it won't get clobbered by the download.
4161 Filename completion now works.
4163 When run under emacs mode, the "info line" command now causes the
4164 arrow to point to the line specified. Also, "info line" prints
4165 addresses in symbolic form (as well as hex).
4167 All vxworks based targets now support a user settable option, called
4168 vxworks-timeout. This option represents the number of seconds gdb
4169 should wait for responses to rpc's. You might want to use this if
4170 your vxworks target is, perhaps, a slow software simulator or happens
4171 to be on the far side of a thin network line.
4175 This release contains support for using a DEC alpha as a GDB host for
4176 cross debugging. Native alpha debugging is not supported yet.
4179 *** Changes in GDB-4.9:
4183 This is the first GDB release which is accompanied by a matching testsuite.
4184 The testsuite requires installation of dejagnu, which should be available
4185 via ftp from most sites that carry GNU software.
4189 'Cfront' style demangling has had its name changed to 'ARM' style, to
4190 emphasize that it was written from the specifications in the C++ Annotated
4191 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4192 disclaimers, it still generated too much confusion with users attempting to
4193 use gdb with AT&T cfront.
4197 GDB now uses a standard remote interface to a simulator library.
4198 So far, the library contains simulators for the Zilog Z8001/2, the
4199 Hitachi H8/300, H8/500 and Super-H.
4201 * New targets supported
4203 H8/300 simulator h8300-hitachi-hms or h8300hms
4204 H8/500 simulator h8500-hitachi-hms or h8500hms
4205 SH simulator sh-hitachi-hms or sh
4206 Z8000 simulator z8k-zilog-none or z8ksim
4207 IDT MIPS board over serial line mips-idt-ecoff
4209 Cross-debugging to GO32 targets is supported. It requires a custom
4210 version of the i386-stub.c module which is integrated with the
4211 GO32 memory extender.
4213 * New remote protocols
4215 MIPS remote debugging protocol.
4217 * New source languages supported
4219 This version includes preliminary support for Chill, a Pascal like language
4220 used by telecommunications companies. Chill support is also being integrated
4221 into the GNU compiler, but we don't know when it will be publically available.
4224 *** Changes in GDB-4.8:
4226 * HP Precision Architecture supported
4228 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4229 version of this support was available as a set of patches from the
4230 University of Utah. GDB does not support debugging of programs
4231 compiled with the HP compiler, because HP will not document their file
4232 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4233 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4235 Many problems in the preliminary version have been fixed.
4237 * Faster and better demangling
4239 We have improved template demangling and fixed numerous bugs in the GNU style
4240 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4241 character types (wchar_t) are now supported. Demangling of each symbol is now
4242 only done once, and is cached when the symbol table for a file is read in.
4243 This results in a small increase in memory usage for C programs, a moderate
4244 increase in memory usage for C++ programs, and a fantastic speedup in
4247 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4248 from the specifications in the Annotated Reference Manual, which AT&T's
4249 compiler does not actually implement.
4251 * G++ multiple inheritance compiler problem
4253 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4254 inheritance lattices was reworked to properly discover ambiguities. We
4255 recently found an example which causes this new algorithm to fail in a
4256 very subtle way, producing bad debug information for those classes.
4257 The file 'gcc.patch' (in this directory) can be applied to gcc to
4258 circumvent the problem. A future GCC release will contain a complete
4261 The previous G++ debug info problem (mentioned below for the gdb-4.7
4262 release) is fixed in gcc version 2.3.2.
4264 * Improved configure script
4266 The `configure' script will now attempt to guess your system type if
4267 you don't supply a host system type. The old scheme of supplying a
4268 host system triplet is preferable over using this. All the magic is
4269 done in the new `config.guess' script. Examine it for details.
4271 We have also brought our configure script much more in line with the FSF's
4272 version. It now supports the --with-xxx options. In particular,
4273 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4274 The resulting GDB will not be able to read arbitrary object file formats --
4275 only the format ``expected'' to be used on the configured target system.
4276 We hope to make this the default in a future release.
4278 * Documentation improvements
4280 There's new internal documentation on how to modify GDB, and how to
4281 produce clean changes to the code. We implore people to read it
4282 before submitting changes.
4284 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4285 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4286 `info' files are also provided. To build `info' files from scratch,
4287 you will need the latest `makeinfo' release, which will be available in
4288 a future texinfo-X.Y release.
4290 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4291 We're not sure exactly which versions have this problem, but it has
4292 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4293 or better. If that isn't possible, there is a patch in
4294 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4295 around this problem.
4299 GDB now supports array constants that can be used in expressions typed in by
4300 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4301 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4304 The new directory `gdb/sparclite' contains a program that demonstrates
4305 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4307 * New native hosts supported
4309 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4310 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4312 * New targets supported
4314 AMD 29k family via UDI a29k-amd-udi or udi29k
4316 * New file formats supported
4318 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4319 HPUX core files, and SCO 3.2v2 core files.
4323 Attaching to processes now works again; thanks for the many bug reports.
4325 We have also stomped on a bunch of core dumps caused by
4326 printf_filtered("%s") problems.
4328 We eliminated a copyright problem on the rpc and ptrace header files
4329 for VxWorks, which was discovered at the last minute during the 4.7
4330 release. You should now be able to build a VxWorks GDB.
4332 You can now interrupt gdb while an attached process is running. This
4333 will cause the attached process to stop, and give control back to GDB.
4335 We fixed problems caused by using too many file descriptors
4336 for reading symbols from object files and libraries. This was
4337 especially a problem for programs that used many (~100) shared
4340 The `step' command now only enters a subroutine if there is line number
4341 information for the subroutine. Otherwise it acts like the `next'
4342 command. Previously, `step' would enter subroutines if there was
4343 any debugging information about the routine. This avoids problems
4344 when using `cc -g1' on MIPS machines.
4346 * Internal improvements
4348 GDB's internal interfaces have been improved to make it easier to support
4349 debugging of multiple languages in the future.
4351 GDB now uses a common structure for symbol information internally.
4352 Minimal symbols (derived from linkage symbols in object files), partial
4353 symbols (from a quick scan of debug information), and full symbols
4354 contain a common subset of information, making it easier to write
4355 shared code that handles any of them.
4357 * New command line options
4359 We now accept --silent as an alias for --quiet.
4363 The memory-mapped-malloc library is now licensed under the GNU Library
4364 General Public License.
4366 *** Changes in GDB-4.7:
4368 * Host/native/target split
4370 GDB has had some major internal surgery to untangle the support for
4371 hosts and remote targets. Now, when you configure GDB for a remote
4372 target, it will no longer load in all of the support for debugging
4373 local programs on the host. When fully completed and tested, this will
4374 ensure that arbitrary host/target combinations are possible.
4376 The primary conceptual shift is to separate the non-portable code in
4377 GDB into three categories. Host specific code is required any time GDB
4378 is compiled on that host, regardless of the target. Target specific
4379 code relates to the peculiarities of the target, but can be compiled on
4380 any host. Native specific code is everything else: it can only be
4381 built when the host and target are the same system. Child process
4382 handling and core file support are two common `native' examples.
4384 GDB's use of /proc for controlling Unix child processes is now cleaner.
4385 It has been split out into a single module under the `target_ops' vector,
4386 plus two native-dependent functions for each system that uses /proc.
4388 * New hosts supported
4390 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4391 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4392 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4394 * New targets supported
4396 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4397 68030 and CPU32 m68030-*-*, m68332-*-*
4399 * New native hosts supported
4401 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4402 (386bsd is not well tested yet)
4403 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4405 * New file formats supported
4407 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4408 supports reading of `a.out.adobe' object files, which are an a.out
4409 format extended with minimal information about multiple sections.
4413 `show copying' is the same as the old `info copying'.
4414 `show warranty' is the same as `info warrantee'.
4415 These were renamed for consistency. The old commands continue to work.
4417 `info handle' is a new alias for `info signals'.
4419 You can now define pre-command hooks, which attach arbitrary command
4420 scripts to any command. The commands in the hook will be executed
4421 prior to the user's command. You can also create a hook which will be
4422 executed whenever the program stops. See gdb.texinfo.
4426 We now deal with Cfront style name mangling, and can even extract type
4427 info from mangled symbols. GDB can automatically figure out which
4428 symbol mangling style your C++ compiler uses.
4430 Calling of methods and virtual functions has been improved as well.
4434 The crash that occured when debugging Sun Ansi-C compiled binaries is
4435 fixed. This was due to mishandling of the extra N_SO stabs output
4438 We also finally got Ultrix 4.2 running in house, and fixed core file
4439 support, with help from a dozen people on the net.
4441 John M. Farrell discovered that the reason that single-stepping was so
4442 slow on all of the Mips based platforms (primarily SGI and DEC) was
4443 that we were trying to demangle and lookup a symbol used for internal
4444 purposes on every instruction that was being stepped through. Changing
4445 the name of that symbol so that it couldn't be mistaken for a C++
4446 mangled symbol sped things up a great deal.
4448 Rich Pixley sped up symbol lookups in general by getting much smarter
4449 about when C++ symbol mangling is necessary. This should make symbol
4450 completion (TAB on the command line) much faster. It's not as fast as
4451 we'd like, but it's significantly faster than gdb-4.6.
4455 A new user controllable variable 'call_scratch_address' can
4456 specify the location of a scratch area to be used when GDB
4457 calls a function in the target. This is necessary because the
4458 usual method of putting the scratch area on the stack does not work
4459 in systems that have separate instruction and data spaces.
4461 We integrated changes to support the 29k UDI (Universal Debugger
4462 Interface), but discovered at the last minute that we didn't have all
4463 of the appropriate copyright paperwork. We are working with AMD to
4464 resolve this, and hope to have it available soon.
4468 We have sped up the remote serial line protocol, especially for targets
4469 with lots of registers. It now supports a new `expedited status' ('T')
4470 message which can be used in place of the existing 'S' status message.
4471 This allows the remote stub to send only the registers that GDB
4472 needs to make a quick decision about single-stepping or conditional
4473 breakpoints, eliminating the need to fetch the entire register set for
4474 each instruction being stepped through.
4476 The GDB remote serial protocol now implements a write-through cache for
4477 registers, only re-reading the registers if the target has run.
4479 There is also a new remote serial stub for SPARC processors. You can
4480 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4481 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4482 processor with a serial port.
4486 Configure.in files have become much easier to read and modify. A new
4487 `table driven' format makes it more obvious what configurations are
4488 supported, and what files each one uses.
4492 There is a new opcodes library which will eventually contain all of the
4493 disassembly routines and opcode tables. At present, it only contains
4494 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4495 disassembler (binutils/objdump) to share these routines.
4497 The libiberty library is now copylefted under the GNU Library General
4498 Public License. This allows more liberal use, and was done so libg++
4499 can use it. This makes no difference to GDB, since the Library License
4500 grants all the rights from the General Public License.
4504 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4505 reference to the stabs symbol info used by the debugger. It is (as far
4506 as we know) the only published document on this fascinating topic. We
4507 encourage you to read it, compare it to the stabs information on your
4508 system, and send improvements on the document in general (to
4509 bug-gdb@prep.ai.mit.edu).
4511 And, of course, many bugs have been fixed.
4514 *** Changes in GDB-4.6:
4516 * Better support for C++ function names
4518 GDB now accepts as input the "demangled form" of C++ overloaded function
4519 names and member function names, and can do command completion on such names
4520 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4521 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4522 Make use of command completion, it is your friend.
4524 GDB also now accepts a variety of C++ mangled symbol formats. They are
4525 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4526 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4527 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4528 for the list of formats.
4530 * G++ symbol mangling problem
4532 Recent versions of gcc have a bug in how they emit debugging information for
4533 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4534 directory) can be applied to gcc to fix the problem. Alternatively, if you
4535 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4536 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4537 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4540 * New 'maintenance' command
4542 All of the commands related to hacking GDB internals have been moved out of
4543 the main command set, and now live behind the 'maintenance' command. This
4544 can also be abbreviated as 'mt'. The following changes were made:
4546 dump-me -> maintenance dump-me
4547 info all-breakpoints -> maintenance info breakpoints
4548 printmsyms -> maintenance print msyms
4549 printobjfiles -> maintenance print objfiles
4550 printpsyms -> maintenance print psymbols
4551 printsyms -> maintenance print symbols
4553 The following commands are new:
4555 maintenance demangle Call internal GDB demangler routine to
4556 demangle a C++ link name and prints the result.
4557 maintenance print type Print a type chain for a given symbol
4559 * Change to .gdbinit file processing
4561 We now read the $HOME/.gdbinit file before processing the argv arguments
4562 (e.g. reading symbol files or core files). This allows global parameters to
4563 be set, which will apply during the symbol reading. The ./.gdbinit is still
4564 read after argv processing.
4566 * New hosts supported
4568 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4570 GNU/Linux support i386-unknown-linux or linux
4572 We are also including code to support the HP/PA running BSD and HPUX. This
4573 is almost guaranteed not to work, as we didn't have time to test or build it
4574 for this release. We are including it so that the more adventurous (or
4575 masochistic) of you can play with it. We also had major problems with the
4576 fact that the compiler that we got from HP doesn't support the -g option.
4579 * New targets supported
4581 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4583 * More smarts about finding #include files
4585 GDB now remembers the compilation directory for all include files, and for
4586 all files from which C is generated (like yacc and lex sources). This
4587 greatly improves GDB's ability to find yacc/lex sources, and include files,
4588 especially if you are debugging your program from a directory different from
4589 the one that contains your sources.
4591 We also fixed a bug which caused difficulty with listing and setting
4592 breakpoints in include files which contain C code. (In the past, you had to
4593 try twice in order to list an include file that you hadn't looked at before.)
4595 * Interesting infernals change
4597 GDB now deals with arbitrary numbers of sections, where the symbols for each
4598 section must be relocated relative to that section's landing place in the
4599 target's address space. This work was needed to support ELF with embedded
4600 stabs used by Solaris-2.0.
4602 * Bug fixes (of course!)
4604 There have been loads of fixes for the following things:
4605 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4606 i960, stabs, DOS(GO32), procfs, etc...
4608 See the ChangeLog for details.
4610 *** Changes in GDB-4.5:
4612 * New machines supported (host and target)
4614 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4616 SGI Irix-4.x mips-sgi-irix4 or iris4
4618 * New malloc package
4620 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4621 Mmalloc is capable of handling mutiple heaps of memory. It is also
4622 capable of saving a heap to a file, and then mapping it back in later.
4623 This can be used to greatly speedup the startup of GDB by using a
4624 pre-parsed symbol table which lives in a mmalloc managed heap. For
4625 more details, please read mmalloc/mmalloc.texi.
4629 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4630 'help info proc' for details.
4632 * MIPS ecoff symbol table format
4634 The code that reads MIPS symbol table format is now supported on all hosts.
4635 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4638 * File name changes for MS-DOS
4640 Many files in the config directories have been renamed to make it easier to
4641 support GDB on MS-DOSe systems (which have very restrictive file name
4642 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4643 environment) is close to working but has some remaining problems. Note
4644 that debugging of DOS programs is not supported, due to limitations
4645 in the ``operating system'', but it can be used to host cross-debugging.
4647 * Cross byte order fixes
4649 Many fixes have been made to support cross debugging of Sparc and MIPS
4650 targets from hosts whose byte order differs.
4652 * New -mapped and -readnow options
4654 If memory-mapped files are available on your system through the 'mmap'
4655 system call, you can use the -mapped option on the `file' or
4656 `symbol-file' commands to cause GDB to write the symbols from your
4657 program into a reusable file. If the program you are debugging is
4658 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4659 Future GDB debugging sessions will notice the presence of this file,
4660 and will quickly map in symbol information from it, rather than reading
4661 the symbol table from the executable program. Using the '-mapped'
4662 option in a GDB `file' or `symbol-file' command has the same effect as
4663 starting GDB with the '-mapped' command-line option.
4665 You can cause GDB to read the entire symbol table immediately by using
4666 the '-readnow' option with any of the commands that load symbol table
4667 information (or on the GDB command line). This makes the command
4668 slower, but makes future operations faster.
4670 The -mapped and -readnow options are typically combined in order to
4671 build a `fred.syms' file that contains complete symbol information.
4672 A simple GDB invocation to do nothing but build a `.syms' file for future
4675 gdb -batch -nx -mapped -readnow programname
4677 The `.syms' file is specific to the host machine on which GDB is run.
4678 It holds an exact image of GDB's internal symbol table. It cannot be
4679 shared across multiple host platforms.
4681 * longjmp() handling
4683 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4684 siglongjmp() without losing control. This feature has not yet been ported to
4685 all systems. It currently works on many 386 platforms, all MIPS-based
4686 platforms (SGI, DECstation, etc), and Sun3/4.
4690 Preliminary work has been put in to support the new Solaris OS from Sun. At
4691 this time, it can control and debug processes, but it is not capable of
4696 As always, many many bug fixes. The major areas were with g++, and mipsread.
4697 People using the MIPS-based platforms should experience fewer mysterious
4698 crashes and trashed symbol tables.
4700 *** Changes in GDB-4.4:
4702 * New machines supported (host and target)
4704 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4706 BSD Reno on Vax vax-dec-bsd
4707 Ultrix on Vax vax-dec-ultrix
4709 * New machines supported (target)
4711 AMD 29000 embedded, using EBMON a29k-none-none
4715 GDB continues to improve its handling of C++. `References' work better.
4716 The demangler has also been improved, and now deals with symbols mangled as
4717 per the Annotated C++ Reference Guide.
4719 GDB also now handles `stabs' symbol information embedded in MIPS
4720 `ecoff' symbol tables. Since the ecoff format was not easily
4721 extensible to handle new languages such as C++, this appeared to be a
4722 good way to put C++ debugging info into MIPS binaries. This option
4723 will be supported in the GNU C compiler, version 2, when it is
4726 * New features for SVR4
4728 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4729 shared libraries. Debugging dynamically linked programs should present
4730 only minor differences from debugging statically linked programs.
4732 The `info proc' command will print out information about any process
4733 on an SVR4 system (including the one you are debugging). At the moment,
4734 it prints the address mappings of the process.
4736 If you bring up GDB on another SVR4 system, please send mail to
4737 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4739 * Better dynamic linking support in SunOS
4741 Reading symbols from shared libraries which contain debugging symbols
4742 now works properly. However, there remain issues such as automatic
4743 skipping of `transfer vector' code during function calls, which
4744 make it harder to debug code in a shared library, than to debug the
4745 same code linked statically.
4749 GDB is now using the latest `getopt' routines from the FSF. This
4750 version accepts the -- prefix for options with long names. GDB will
4751 continue to accept the old forms (-option and +option) as well.
4752 Various single letter abbreviations for options have been explicity
4753 added to the option table so that they won't get overshadowed in the
4754 future by other options that begin with the same letter.
4758 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4759 Many assorted bugs have been handled. Many more remain to be handled.
4760 See the various ChangeLog files (primarily in gdb and bfd) for details.
4763 *** Changes in GDB-4.3:
4765 * New machines supported (host and target)
4767 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4768 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4769 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4771 * Almost SCO Unix support
4773 We had hoped to support:
4774 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4775 (except for core file support), but we discovered very late in the release
4776 that it has problems with process groups that render gdb unusable. Sorry
4777 about that. I encourage people to fix it and post the fixes.
4779 * Preliminary ELF and DWARF support
4781 GDB can read ELF object files on System V Release 4, and can handle
4782 debugging records for C, in DWARF format, in ELF files. This support
4783 is preliminary. If you bring up GDB on another SVR4 system, please
4784 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4789 GDB now uses the latest `readline' library. One user-visible change
4790 is that two tabs will list possible command completions, which previously
4791 required typing M-? (meta-question mark, or ESC ?).
4795 The `stepi' bug that many of you noticed has been squashed.
4796 Many bugs in C++ have been handled. Many more remain to be handled.
4797 See the various ChangeLog files (primarily in gdb and bfd) for details.
4799 * State of the MIPS world (in case you wondered):
4801 GDB can understand the symbol tables emitted by the compilers
4802 supplied by most vendors of MIPS-based machines, including DEC. These
4803 symbol tables are in a format that essentially nobody else uses.
4805 Some versions of gcc come with an assembler post-processor called
4806 mips-tfile. This program is required if you want to do source-level
4807 debugging of gcc-compiled programs. I believe FSF does not ship
4808 mips-tfile with gcc version 1, but it will eventually come with gcc
4811 Debugging of g++ output remains a problem. g++ version 1.xx does not
4812 really support it at all. (If you're lucky, you should be able to get
4813 line numbers and stack traces to work, but no parameters or local
4814 variables.) With some work it should be possible to improve the
4817 When gcc version 2 is released, you will have somewhat better luck.
4818 However, even then you will get confusing results for inheritance and
4821 We will eventually provide full debugging of g++ output on
4822 DECstations. This will probably involve some kind of stabs-in-ecoff
4823 encapulation, but the details have not been worked out yet.
4826 *** Changes in GDB-4.2:
4828 * Improved configuration
4830 Only one copy of `configure' exists now, and it is not self-modifying.
4831 Porting BFD is simpler.
4835 The `step' and `next' commands now only stop at the first instruction
4836 of a source line. This prevents the multiple stops that used to occur
4837 in switch statements, for-loops, etc. `Step' continues to stop if a
4838 function that has debugging information is called within the line.
4842 Lots of small bugs fixed. More remain.
4844 * New host supported (not target)
4846 Intel 386 PC clone running Mach i386-none-mach
4849 *** Changes in GDB-4.1:
4851 * Multiple source language support
4853 GDB now has internal scaffolding to handle several source languages.
4854 It determines the type of each source file from its filename extension,
4855 and will switch expression parsing and number formatting to match the
4856 language of the function in the currently selected stack frame.
4857 You can also specifically set the language to be used, with
4858 `set language c' or `set language modula-2'.
4862 GDB now has preliminary support for the GNU Modula-2 compiler,
4863 currently under development at the State University of New York at
4864 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4865 continue through the fall of 1991 and into 1992.
4867 Other Modula-2 compilers are currently not supported, and attempting to
4868 debug programs compiled with them will likely result in an error as the
4869 symbol table is read. Feel free to work on it, though!
4871 There are hooks in GDB for strict type checking and range checking,
4872 in the `Modula-2 philosophy', but they do not currently work.
4876 GDB can now write to executable and core files (e.g. patch
4877 a variable's value). You must turn this switch on, specify
4878 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4879 by assigning a new value to a variable. Modifications take
4882 * Automatic SunOS shared library reading
4884 When you run your program, GDB automatically determines where its
4885 shared libraries (if any) have been loaded, and reads their symbols.
4886 The `share' command is no longer needed. This also works when
4887 examining core files.
4891 You can specify the number of lines that the `list' command shows.
4894 * New machines supported (host and target)
4896 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4897 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4898 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4900 * New hosts supported (not targets)
4902 IBM RT/PC: romp-ibm-aix or rtpc
4904 * New targets supported (not hosts)
4906 AMD 29000 embedded with COFF a29k-none-coff
4907 AMD 29000 embedded with a.out a29k-none-aout
4908 Ultracomputer remote kernel debug a29k-nyu-kern
4910 * New remote interfaces
4916 *** Changes in GDB-4.0:
4920 Wide output is wrapped at good places to make the output more readable.
4922 Gdb now supports cross-debugging from a host machine of one type to a
4923 target machine of another type. Communication with the target system
4924 is over serial lines. The ``target'' command handles connecting to the
4925 remote system; the ``load'' command will download a program into the
4926 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4927 also supports debugging of realtime processes running under VxWorks,
4928 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4929 stub on the target system.
4931 New CPUs supported include the AMD 29000 and Intel 960.
4933 GDB now reads object files and symbol tables via a ``binary file''
4934 library, which allows a single copy of GDB to debug programs of multiple
4935 object file types such as a.out and coff.
4937 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4938 refcard.dvi and refcard.ps are available to format it).
4941 * Control-Variable user interface simplified
4943 All variables that control the operation of the debugger can be set
4944 by the ``set'' command, and displayed by the ``show'' command.
4946 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4947 ``Show prompt'' produces the response:
4948 Gdb's prompt is new-gdb=>.
4950 What follows are the NEW set commands. The command ``help set'' will
4951 print a complete list of old and new set commands. ``help set FOO''
4952 will give a longer description of the variable FOO. ``show'' will show
4953 all of the variable descriptions and their current settings.
4955 confirm on/off: Enables warning questions for operations that are
4956 hard to recover from, e.g. rerunning the program while
4957 it is already running. Default is ON.
4959 editing on/off: Enables EMACS style command line editing
4960 of input. Previous lines can be recalled with
4961 control-P, the current line can be edited with control-B,
4962 you can search for commands with control-R, etc.
4965 history filename NAME: NAME is where the gdb command history
4966 will be stored. The default is .gdb_history,
4967 or the value of the environment variable
4970 history size N: The size, in commands, of the command history. The
4971 default is 256, or the value of the environment variable
4974 history save on/off: If this value is set to ON, the history file will
4975 be saved after exiting gdb. If set to OFF, the
4976 file will not be saved. The default is OFF.
4978 history expansion on/off: If this value is set to ON, then csh-like
4979 history expansion will be performed on
4980 command line input. The default is OFF.
4982 radix N: Sets the default radix for input and output. It can be set
4983 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4984 in the current radix, so "set radix 10" is always a no-op.
4986 height N: This integer value is the number of lines on a page. Default
4987 is 24, the current `stty rows'' setting, or the ``li#''
4988 setting from the termcap entry matching the environment
4991 width N: This integer value is the number of characters on a line.
4992 Default is 80, the current `stty cols'' setting, or the ``co#''
4993 setting from the termcap entry matching the environment
4996 Note: ``set screensize'' is obsolete. Use ``set height'' and
4997 ``set width'' instead.
4999 print address on/off: Print memory addresses in various command displays,
5000 such as stack traces and structure values. Gdb looks
5001 more ``symbolic'' if you turn this off; it looks more
5002 ``machine level'' with it on. Default is ON.
5004 print array on/off: Prettyprint arrays. New convenient format! Default
5007 print demangle on/off: Print C++ symbols in "source" form if on,
5010 print asm-demangle on/off: Same, for assembler level printouts
5013 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5016 * Support for Epoch Environment.
5018 The epoch environment is a version of Emacs v18 with windowing. One
5019 new command, ``inspect'', is identical to ``print'', except that if you
5020 are running in the epoch environment, the value is printed in its own
5024 * Support for Shared Libraries
5026 GDB can now debug programs and core files that use SunOS shared libraries.
5027 Symbols from a shared library cannot be referenced
5028 before the shared library has been linked with the program (this
5029 happens after you type ``run'' and before the function main() is entered).
5030 At any time after this linking (including when examining core files
5031 from dynamically linked programs), gdb reads the symbols from each
5032 shared library when you type the ``sharedlibrary'' command.
5033 It can be abbreviated ``share''.
5035 sharedlibrary REGEXP: Load shared object library symbols for files
5036 matching a unix regular expression. No argument
5037 indicates to load symbols for all shared libraries.
5039 info sharedlibrary: Status of loaded shared libraries.
5044 A watchpoint stops execution of a program whenever the value of an
5045 expression changes. Checking for this slows down execution
5046 tremendously whenever you are in the scope of the expression, but is
5047 quite useful for catching tough ``bit-spreader'' or pointer misuse
5048 problems. Some machines such as the 386 have hardware for doing this
5049 more quickly, and future versions of gdb will use this hardware.
5051 watch EXP: Set a watchpoint (breakpoint) for an expression.
5053 info watchpoints: Information about your watchpoints.
5055 delete N: Deletes watchpoint number N (same as breakpoints).
5056 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5057 enable N: Re-enables watchpoint number N (same as breakpoints).
5060 * C++ multiple inheritance
5062 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5065 * C++ exception handling
5067 Gdb now supports limited C++ exception handling. Besides the existing
5068 ability to breakpoint on an exception handler, gdb can breakpoint on
5069 the raising of an exception (before the stack is peeled back to the
5072 catch FOO: If there is a FOO exception handler in the dynamic scope,
5073 set a breakpoint to catch exceptions which may be raised there.
5074 Multiple exceptions (``catch foo bar baz'') may be caught.
5076 info catch: Lists all exceptions which may be caught in the
5077 current stack frame.
5080 * Minor command changes
5082 The command ``call func (arg, arg, ...)'' now acts like the print
5083 command, except it does not print or save a value if the function's result
5084 is void. This is similar to dbx usage.
5086 The ``up'' and ``down'' commands now always print the frame they end up
5087 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5088 frames without printing.
5090 * New directory command
5092 'dir' now adds directories to the FRONT of the source search path.
5093 The path starts off empty. Source files that contain debug information
5094 about the directory in which they were compiled can be found even
5095 with an empty path; Sun CC and GCC include this information. If GDB can't
5096 find your source file in the current directory, type "dir .".
5098 * Configuring GDB for compilation
5100 For normal use, type ``./configure host''. See README or gdb.texinfo
5103 GDB now handles cross debugging. If you are remotely debugging between
5104 two different machines, type ``./configure host -target=targ''.
5105 Host is the machine where GDB will run; targ is the machine
5106 where the program that you are debugging will run.