1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
8 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
11 * GDB now supports access to MIPS DSP registers on Linux targets.
13 * GDB now supports debugging microMIPS binaries.
15 * The "info os" command on GNU/Linux can now display information on
16 several new classes of objects managed by the operating system:
17 "info os procgroups" lists process groups
18 "info os files" lists file descriptors
19 "info os sockets" lists internet-domain sockets
20 "info os shm" lists shared-memory regions
21 "info os semaphores" lists semaphores
22 "info os msg" lists message queues
23 "info os modules" lists loaded kernel modules
25 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
26 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
27 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
28 options and inspect the probe arguments using the new $_probe_arg family
29 of convenience variables. You can obtain more information about SystemTap
30 in <http://sourceware.org/systemtap/>.
32 * GDB now supports reversible debugging on ARM, it allows you to
33 debug basic ARM and THUMB instructions, and provides
34 record/replay support.
36 * The option "symbol-reloading" has been deleted as it is no longer used.
40 ** GDB commands implemented in Python can now be put in command class
43 ** The "maint set python print-stack on|off" is now deleted.
45 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
46 apply "flag enum"-style pretty-printing to any enum.
48 ** gdb.lookup_symbol can now work when there is no current frame.
50 ** gdb.Symbol now has a 'line' attribute, holding the line number in
51 the source at which the symbol was defined.
53 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
54 method 'value'. The former indicates whether the symbol needs a
55 frame in order to compute its value, and the latter computes the
58 ** A new method 'referenced_value' on gdb.Value objects which can
59 dereference pointer as well as C++ reference values.
61 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
62 which return the global and static blocks (as gdb.Block objects),
63 of the underlying symbol table, respectively.
65 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
66 object associated with a PC value.
68 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
69 of the address range occupied by code for the current source line.
71 * Go language support.
72 GDB now supports debugging programs written in the Go programming
75 * GDBserver now supports stdio connections.
76 E.g. (gdb) target remote | ssh myhost gdbserver - hello
78 * The binary "gdbtui" can no longer be built or installed.
79 Use "gdb -tui" instead.
81 * GDB will now print "flag" enums specially. A flag enum is one where
82 all the enumerator values have no bits in common when pairwise
83 "and"ed. When printing a value whose type is a flag enum, GDB will
84 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
85 (gdb) print (enum E) 3
88 * The filename part of a linespec will now match trailing components
89 of a source file name. For example, "break gcc/expr.c:1000" will
90 now set a breakpoint in build/gcc/expr.c, but not
93 * The "info proc" and "generate-core-file" commands will now also
94 work on remote targets connected to GDBserver on Linux.
96 * The command "info catch" has been removed. It has been disabled
99 * The "catch exception" and "catch assert" commands now accept
100 a condition at the end of the command, much like the "break"
101 command does. For instance:
103 (gdb) catch exception Constraint_Error if Barrier = True
105 Previously, it was possible to add a condition to such catchpoints,
106 but it had to be done as a second step, after the catchpoint had been
107 created, using the "condition" command.
109 * The "info static-tracepoint-marker" command will now also work on
110 native Linux targets with in-process agent.
112 * GDB can now set breakpoints on inlined functions.
114 * The .gdb_index section has been updated to include symbols for
115 inlined functions. GDB will ignore older .gdb_index sections by
116 default, which could cause symbol files to be loaded more slowly
117 until their .gdb_index sections can be recreated. The new option
118 --use-deprecated-index-sections will cause GDB to use any older
119 .gdb_index sections it finds. This will restore performance, but
120 the ability to set breakpoints on inlined functions will be lost
121 in symbol files with older .gdb_index sections.
123 The .gdb_index section has also been updated to record more information
124 about each symbol. This speeds up the "info variables", "info functions"
125 and "info types" commands when used with programs having the .gdb_index
126 section, as well as speeding up debugging with shared libraries using
127 the .gdb_index section.
129 * Ada support for GDB/MI Variable Objects has been added.
131 * GDB can now support 'breakpoint always-inserted mode' in 'record'
136 ** New command -info-os is the MI equivalent of "info os".
138 ** Output logs ("set logging" and related) now include MI output.
142 ** "catch load" and "catch unload" can be used to stop when a shared
143 library is loaded or unloaded, respectively.
145 ** "enable count" can be used to auto-disable a breakpoint after
148 ** "info vtbl" can be used to show the virtual method tables for
149 C++ and Java objects.
151 ** "explore" and its sub commands "explore value" and "explore type"
152 can be used to reccursively explore values and types of
153 expressions. These commands are available only if GDB is
154 configured with '--with-python'.
156 ** "info auto-load" shows status of all kinds of auto-loaded files,
157 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
158 sequences of commands files, "info auto-load python-scripts"
159 shows status of auto-loading Python script files,
160 "info auto-load local-gdbinit" shows status of loading init file
161 (.gdbinit) from current directory and "info auto-load libthread-db" shows
162 status of inferior specific thread debugging shared library loading.
164 ** "info auto-load-scripts", "set auto-load-scripts on|off"
165 and "show auto-load-scripts" commands have been deprecated, use their
166 "info auto-load python-scripts", "set auto-load python-scripts on|off"
167 and "show auto-load python-scripts" counterparts instead.
169 ** "dprintf location,format,args..." creates a dynamic printf, which
170 is basically a breakpoint that does a printf and immediately
171 resumes your program's execution, so it is like a printf that you
172 can insert dynamically at runtime instead of at compiletime.
174 ** "set print symbol"
176 Controls whether GDB attempts to display the symbol, if any,
177 corresponding to addresses it prints. This defaults to "on", but
178 you can set it to "off" to restore GDB's previous behavior.
180 * Deprecated commands
182 ** For the Renesas Super-H architecture, the "regs" command has been
183 deprecated, and "info all-registers" should be used instead.
187 Renesas RL78 rl78-*-elf
188 HP OpenVMS ia64 ia64-hp-openvms*
190 * GDBserver supports evaluation of breakpoint conditions. When
191 support is advertised by GDBserver, GDB may be told to send the
192 breakpoint conditions in bytecode form to GDBserver. GDBserver
193 will only report the breakpoint trigger to GDB when its condition
199 show mips compression
200 Select the compressed ISA encoding used in functions that have no symbol
201 information available. The encoding can be set to either of:
204 and is updated automatically from ELF file flags if available.
206 set breakpoint condition-evaluation
207 show breakpoint condition-evaluation
208 Control whether breakpoint conditions are evaluated by GDB ("host") or by
209 GDBserver ("target"). Default option "auto" chooses the most efficient
211 This option can improve debugger efficiency depending on the speed of the
215 Disable auto-loading globally.
218 Show auto-loading setting of all kinds of auto-loaded files.
220 set auto-load gdb-scripts on|off
221 show auto-load gdb-scripts
222 Control auto-loading of GDB canned sequences of commands files.
224 set auto-load python-scripts on|off
225 show auto-load python-scripts
226 Control auto-loading of Python script files.
228 set auto-load local-gdbinit on|off
229 show auto-load local-gdbinit
230 Control loading of init file (.gdbinit) from current directory.
232 set auto-load libthread-db on|off
233 show auto-load libthread-db
234 Control auto-loading of inferior specific thread debugging shared library.
236 set auto-load scripts-directory <dir1>[:<dir2>...]
237 show auto-load scripts-directory
238 Set a list of directories from which to load auto-loaded scripts.
239 Automatically loaded Python scripts and GDB scripts are located in one
240 of the directories listed by this option.
241 The delimiter (':' above) may differ according to the host platform.
243 set auto-load safe-path <dir1>[:<dir2>...]
244 show auto-load safe-path
245 Set a list of directories from which it is safe to auto-load files.
246 The delimiter (':' above) may differ according to the host platform.
248 set debug auto-load on|off
250 Control display of debugging info for auto-loading the files above.
252 set dprintf-style gdb|call|agent
254 Control the way in which a dynamic printf is performed; "gdb"
255 requests a GDB printf command, while "call" causes dprintf to call a
256 function in the inferior. "agent" requests that the target agent
257 (such as GDBserver) do the printing.
259 set dprintf-function <expr>
260 show dprintf-function
261 set dprintf-channel <expr>
263 Set the function and optional first argument to the call when using
264 the "call" style of dynamic printf.
266 set disconnected-dprintf on|off
267 show disconnected-dprintf
268 Control whether agent-style dynamic printfs continue to be in effect
269 after GDB disconnects.
271 * New configure options
274 Configure default value for the 'set auto-load scripts-directory'
275 setting above. It defaults to '$debugdir:$datadir/auto-load',
276 $debugdir representing global debugging info directories (available
277 via 'show debug-file-directory') and $datadir representing GDB's data
278 directory (available via 'show data-directory').
280 --with-auto-load-safe-path
281 Configure default value for the 'set auto-load safe-path' setting
282 above. It defaults to the --with-auto-load-dir setting.
284 --without-auto-load-safe-path
285 Set 'set auto-load safe-path' to '/', effectively disabling this
290 z0/z1 conditional breakpoints extension
292 The z0/z1 breakpoint insertion packets have been extended to carry
293 a list of conditional expressions over to the remote stub depending on the
294 condition evaluation mode. The use of this extension can be controlled
295 via the "set remote conditional-breakpoints-packet" command.
299 Specify the signals which the remote stub may pass to the debugged
300 program without GDB involvement.
302 * New command line options
304 --init-command=FILE, -ix Like --command, -x but execute it
305 before loading inferior.
306 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
307 execute it before loading inferior.
309 *** Changes in GDB 7.4
311 * GDB now handles ambiguous linespecs more consistently; the existing
312 FILE:LINE support has been expanded to other types of linespecs. A
313 breakpoint will now be set on all matching locations in all
314 inferiors, and locations will be added or removed according to
317 * GDB now allows you to skip uninteresting functions and files when
318 stepping with the "skip function" and "skip file" commands.
320 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
321 and "show remote hardware-watchpoint-length-limit". These allows to
322 set or show the maximum length limit (in bytes) of a remote
323 target hardware watchpoint.
325 This allows e.g. to use "unlimited" hardware watchpoints with the
326 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
327 watchpoints are slower than real hardware watchpoints but are
328 significantly faster than gdb software watchpoints.
332 ** The register_pretty_printer function in module gdb.printing now takes
333 an optional `replace' argument. If True, the new printer replaces any
336 ** The "maint set python print-stack on|off" command has been
337 deprecated and will be deleted in GDB 7.5.
338 A new command: "set python print-stack none|full|message" has
339 replaced it. Additionally, the default for "print-stack" is
340 now "message", which just prints the error message without
343 ** A prompt substitution hook (prompt_hook) is now available to the
346 ** A new Python module, gdb.prompt has been added to the GDB Python
347 modules library. This module provides functionality for
348 escape sequences in prompts (used by set/show
349 extended-prompt). These escape sequences are replaced by their
352 ** Python commands and convenience-functions located in
353 'data-directory'/python/gdb/command and
354 'data-directory'/python/gdb/function are now automatically loaded
357 ** Blocks now provide four new attributes. global_block and
358 static_block will return the global and static blocks
359 respectively. is_static and is_global are boolean attributes
360 that indicate if the block is one of those two types.
362 ** Symbols now provide the "type" attribute, the type of the symbol.
364 ** The "gdb.breakpoint" function has been deprecated in favor of
367 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
368 of a function. This class is based on the "finish" command
369 available in the CLI.
371 ** Type objects for struct and union types now allow access to
372 the fields using standard Python dictionary (mapping) methods.
373 For example, "some_type['myfield']" now works, as does
376 ** A new event "gdb.new_objfile" has been added, triggered by loading a
379 ** A new function, "deep_items" has been added to the gdb.types
380 module in the GDB Python modules library. This function returns
381 an iterator over the fields of a struct or union type. Unlike
382 the standard Python "iteritems" method, it will recursively traverse
383 any anonymous fields.
387 ** "*stopped" events can report several new "reason"s, such as
390 ** Breakpoint changes are now notified using new async records, like
391 "=breakpoint-modified".
393 ** New command -ada-task-info.
395 * libthread-db-search-path now supports two special values: $sdir and $pdir.
396 $sdir specifies the default system locations of shared libraries.
397 $pdir specifies the directory where the libpthread used by the application
400 GDB no longer looks in $sdir and $pdir after it has searched the directories
401 mentioned in libthread-db-search-path. If you want to search those
402 directories, they must be specified in libthread-db-search-path.
403 The default value of libthread-db-search-path on GNU/Linux and Solaris
404 systems is now "$sdir:$pdir".
406 $pdir is not supported by gdbserver, it is currently ignored.
407 $sdir is supported by gdbserver.
409 * New configure option --with-iconv-bin.
410 When using the internationalization support like the one in the GNU C
411 library, GDB will invoke the "iconv" program to get a list of supported
412 character sets. If this program lives in a non-standard location, one can
413 use this option to specify where to find it.
415 * When natively debugging programs on PowerPC BookE processors running
416 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
417 watchpoints, which specify a mask in addition to an address to watch.
418 The mask specifies that some bits of an address (the bits which are
419 reset in the mask) should be ignored when matching the address accessed
420 by the inferior against the watchpoint address. See the "PowerPC Embedded"
421 section in the user manual for more details.
423 * The new option --once causes GDBserver to stop listening for connections once
424 the first connection is made. The listening port used by GDBserver will
425 become available after that.
427 * New commands "info macros" and "alias" have been added.
429 * New function parameters suffix @entry specifies value of function parameter
430 at the time the function got called. Entry values are available only since
436 "!" is now an alias of the "shell" command.
437 Note that no space is needed between "!" and SHELL COMMAND.
441 watch EXPRESSION mask MASK_VALUE
442 The watch command now supports the mask argument which allows creation
443 of masked watchpoints, if the current architecture supports this feature.
445 info auto-load-scripts [REGEXP]
446 This command was formerly named "maintenance print section-scripts".
447 It is now generally useful and is no longer a maintenance-only command.
449 info macro [-all] [--] MACRO
450 The info macro command has new options `-all' and `--'. The first for
451 printing all definitions of a macro. The second for explicitly specifying
452 the end of arguments and the beginning of the macro name in case the macro
453 name starts with a hyphen.
455 collect[/s] EXPRESSIONS
456 The tracepoint collect command now takes an optional modifier "/s"
457 that directs it to dereference pointer-to-character types and
458 collect the bytes of memory up to a zero byte. The behavior is
459 similar to what you see when you use the regular print command on a
460 string. An optional integer following the "/s" sets a bound on the
461 number of bytes that will be collected.
464 The trace start command now interprets any supplied arguments as a
465 note to be recorded with the trace run, with an effect similar to
466 setting the variable trace-notes.
469 The trace stop command now interprets any arguments as a note to be
470 mentioned along with the tstatus report that the trace was stopped
471 with a command. The effect is similar to setting the variable
474 * Tracepoints can now be enabled and disabled at any time after a trace
475 experiment has been started using the standard "enable" and "disable"
476 commands. It is now possible to start a trace experiment with no enabled
477 tracepoints; GDB will display a warning, but will allow the experiment to
478 begin, assuming that tracepoints will be enabled as needed while the trace
481 * Fast tracepoints on 32-bit x86-architectures can now be placed at
482 locations with 4-byte instructions, when they were previously
483 limited to locations with instructions of 5 bytes or longer.
487 set debug dwarf2-read
488 show debug dwarf2-read
489 Turns on or off display of debugging messages related to reading
490 DWARF debug info. The default is off.
492 set debug symtab-create
493 show debug symtab-create
494 Turns on or off display of debugging messages related to symbol table
495 creation. The default is off.
499 Set the GDB prompt, and allow escape sequences to be inserted to
500 display miscellaneous information (see 'help set extended-prompt'
501 for the list of sequences). This prompt (and any information
502 accessed through the escape sequences) is updated every time the
505 set print entry-values (both|compact|default|if-needed|no|only|preferred)
506 show print entry-values
507 Set printing of frame argument values at function entry. In some cases
508 GDB can determine the value of function argument which was passed by the
509 function caller, even if the value was modified inside the called function.
511 set debug entry-values
512 show debug entry-values
513 Control display of debugging info for determining frame argument values at
514 function entry and virtual tail call frames.
516 set basenames-may-differ
517 show basenames-may-differ
518 Set whether a source file may have multiple base names.
519 (A "base name" is the name of a file with the directory part removed.
520 Example: The base name of "/home/user/hello.c" is "hello.c".)
521 If set, GDB will canonicalize file names (e.g., expand symlinks)
522 before comparing them. Canonicalization is an expensive operation,
523 but it allows the same file be known by more than one base name.
524 If not set (the default), all source files are assumed to have just
525 one base name, and gdb will do file name comparisons more efficiently.
531 Set a user name and notes for the current and any future trace runs.
532 This is useful for long-running and/or disconnected traces, to
533 inform others (or yourself) as to who is running the trace, supply
534 contact information, or otherwise explain what is going on.
537 show trace-stop-notes
538 Set a note attached to the trace run, that is displayed when the
539 trace has been stopped by a tstop command. This is useful for
540 instance as an explanation, if you are stopping a trace run that was
541 started by someone else.
547 Dynamically enable a tracepoint in a started trace experiment.
551 Dynamically disable a tracepoint in a started trace experiment.
555 Set the user and notes of the trace run.
559 Query the current status of a tracepoint.
563 Query the minimum length of instruction at which a fast tracepoint may
566 * Dcache size (number of lines) and line-size are now runtime-configurable
567 via "set dcache line" and "set dcache line-size" commands.
571 Texas Instruments TMS320C6x tic6x-*-*
575 Renesas RL78 rl78-*-elf
577 *** Changes in GDB 7.3.1
579 * The build failure for NetBSD and OpenBSD targets have now been fixed.
581 *** Changes in GDB 7.3
583 * GDB has a new command: "thread find [REGEXP]".
584 It finds the thread id whose name, target id, or thread extra info
585 matches the given regular expression.
587 * The "catch syscall" command now works on mips*-linux* targets.
589 * The -data-disassemble MI command now supports modes 2 and 3 for
590 dumping the instruction opcodes.
592 * New command line options
594 -data-directory DIR Specify DIR as the "data-directory".
595 This is mostly for testing purposes.
597 * The "maint set python auto-load on|off" command has been renamed to
598 "set auto-load-scripts on|off".
600 * GDB has a new command: "set directories".
601 It is like the "dir" command except that it replaces the
602 source path list instead of augmenting it.
604 * GDB now understands thread names.
606 On GNU/Linux, "info threads" will display the thread name as set by
607 prctl or pthread_setname_np.
609 There is also a new command, "thread name", which can be used to
610 assign a name internally for GDB to display.
613 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
614 has been integrated into GDB.
618 ** The function gdb.Write now accepts an optional keyword 'stream'.
619 This keyword, when provided, will direct the output to either
620 stdout, stderr, or GDB's logging output.
622 ** Parameters can now be be sub-classed in Python, and in particular
623 you may implement the get_set_doc and get_show_doc functions.
624 This improves how Parameter set/show documentation is processed
625 and allows for more dynamic content.
627 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
628 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
629 have an is_valid method.
631 ** Breakpoints can now be sub-classed in Python, and in particular
632 you may implement a 'stop' function that is executed each time
633 the inferior reaches that breakpoint.
635 ** New function gdb.lookup_global_symbol looks up a global symbol.
637 ** GDB values in Python are now callable if the value represents a
638 function. For example, if 'some_value' represents a function that
639 takes two integer parameters and returns a value, you can call
640 that function like so:
642 result = some_value (10,20)
644 ** Module gdb.types has been added.
645 It contains a collection of utilities for working with gdb.Types objects:
646 get_basic_type, has_field, make_enum_dict.
648 ** Module gdb.printing has been added.
649 It contains utilities for writing and registering pretty-printers.
650 New classes: PrettyPrinter, SubPrettyPrinter,
651 RegexpCollectionPrettyPrinter.
652 New function: register_pretty_printer.
654 ** New commands "info pretty-printers", "enable pretty-printer" and
655 "disable pretty-printer" have been added.
657 ** gdb.parameter("directories") is now available.
659 ** New function gdb.newest_frame returns the newest frame in the
662 ** The gdb.InferiorThread class has a new "name" attribute. This
663 holds the thread's name.
665 ** Python Support for Inferior events.
666 Python scripts can add observers to be notified of events
667 occurring in the process being debugged.
668 The following events are currently supported:
669 - gdb.events.cont Continue event.
670 - gdb.events.exited Inferior exited event.
671 - gdb.events.stop Signal received, and Breakpoint hit events.
675 ** GDB now puts template parameters in scope when debugging in an
676 instantiation. For example, if you have:
678 template<int X> int func (void) { return X; }
680 then if you step into func<5>, "print X" will show "5". This
681 feature requires proper debuginfo support from the compiler; it
682 was added to GCC 4.5.
684 ** The motion commands "next", "finish", "until", and "advance" now
685 work better when exceptions are thrown. In particular, GDB will
686 no longer lose control of the inferior; instead, the GDB will
687 stop the inferior at the point at which the exception is caught.
688 This functionality requires a change in the exception handling
689 code that was introduced in GCC 4.5.
691 * GDB now follows GCC's rules on accessing volatile objects when
692 reading or writing target state during expression evaluation.
693 One notable difference to prior behavior is that "print x = 0"
694 no longer generates a read of x; the value of the assignment is
695 now always taken directly from the value being assigned.
697 * GDB now has some support for using labels in the program's source in
698 linespecs. For instance, you can use "advance label" to continue
699 execution to a label.
701 * GDB now has support for reading and writing a new .gdb_index
702 section. This section holds a fast index of DWARF debugging
703 information and can be used to greatly speed up GDB startup and
704 operation. See the documentation for `save gdb-index' for details.
706 * The "watch" command now accepts an optional "-location" argument.
707 When used, this causes GDB to watch the memory referred to by the
708 expression. Such a watchpoint is never deleted due to it going out
711 * GDB now supports thread debugging of core dumps on GNU/Linux.
713 GDB now activates thread debugging using the libthread_db library
714 when debugging GNU/Linux core dumps, similarly to when debugging
715 live processes. As a result, when debugging a core dump file, GDB
716 is now able to display pthread_t ids of threads. For example, "info
717 threads" shows the same output as when debugging the process when it
718 was live. In earlier releases, you'd see something like this:
721 * 1 LWP 6780 main () at main.c:10
723 While now you see this:
726 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
728 It is also now possible to inspect TLS variables when debugging core
731 When debugging a core dump generated on a machine other than the one
732 used to run GDB, you may need to point GDB at the correct
733 libthread_db library with the "set libthread-db-search-path"
734 command. See the user manual for more details on this command.
736 * When natively debugging programs on PowerPC BookE processors running
737 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
738 which stop execution of the inferior whenever it executes an instruction
739 at any address within the specified range. See the "PowerPC Embedded"
740 section in the user manual for more details.
742 * New features in the GDB remote stub, GDBserver
744 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
745 and i686 LynxOS (version 5.x).
747 ** GDBserver is now supported on Blackfin Linux.
749 * New native configurations
751 ia64 HP-UX ia64-*-hpux*
755 Analog Devices, Inc. Blackfin Processor bfin-*
757 * Ada task switching is now supported on sparc-elf targets when
758 debugging a program using the Ravenscar Profile. For more information,
759 see the "Tasking Support when using the Ravenscar Profile" section
760 in the GDB user manual.
762 * Guile support was removed.
764 * New features in the GNU simulator
766 ** The --map-info flag lists all known core mappings.
768 ** CFI flashes may be simulated via the "cfi" device.
770 *** Changes in GDB 7.2
772 * Shared library support for remote targets by default
774 When GDB is configured for a generic, non-OS specific target, like
775 for example, --target=arm-eabi or one of the many *-*-elf targets,
776 GDB now queries remote stubs for loaded shared libraries using the
777 `qXfer:libraries:read' packet. Previously, shared library support
778 was always disabled for such configurations.
782 ** Argument Dependent Lookup (ADL)
784 In C++ ADL lookup directs function search to the namespaces of its
785 arguments even if the namespace has not been imported.
795 Here the compiler will search for `foo' in the namespace of 'b'
796 and find A::foo. GDB now supports this. This construct is commonly
797 used in the Standard Template Library for operators.
799 ** Improved User Defined Operator Support
801 In addition to member operators, GDB now supports lookup of operators
802 defined in a namespace and imported with a `using' directive, operators
803 defined in the global scope, operators imported implicitly from an
804 anonymous namespace, and the ADL operators mentioned in the previous
806 GDB now also supports proper overload resolution for all the previously
807 mentioned flavors of operators.
809 ** static const class members
811 Printing of static const class members that are initialized in the
812 class definition has been fixed.
814 * Windows Thread Information Block access.
816 On Windows targets, GDB now supports displaying the Windows Thread
817 Information Block (TIB) structure. This structure is visible either
818 by using the new command `info w32 thread-information-block' or, by
819 dereferencing the new convenience variable named `$_tlb', a
820 thread-specific pointer to the TIB. This feature is also supported
821 when remote debugging using GDBserver.
825 Static tracepoints are calls in the user program into a tracing
826 library. One such library is a port of the LTTng kernel tracer to
827 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
828 When debugging with GDBserver, GDB now supports combining the GDB
829 tracepoint machinery with such libraries. For example: the user can
830 use GDB to probe a static tracepoint marker (a call from the user
831 program into the tracing library) with the new "strace" command (see
832 "New commands" below). This creates a "static tracepoint" in the
833 breakpoint list, that can be manipulated with the same feature set
834 as fast and regular tracepoints. E.g., collect registers, local and
835 global variables, collect trace state variables, and define
836 tracepoint conditions. In addition, the user can collect extra
837 static tracepoint marker specific data, by collecting the new
838 $_sdata internal variable. When analyzing the trace buffer, you can
839 inspect $_sdata like any other variable available to GDB. For more
840 information, see the "Tracepoints" chapter in GDB user manual. New
841 remote packets have been defined to support static tracepoints, see
842 the "New remote packets" section below.
844 * Better reconstruction of tracepoints after disconnected tracing
846 GDB will attempt to download the original source form of tracepoint
847 definitions when starting a trace run, and then will upload these
848 upon reconnection to the target, resulting in a more accurate
849 reconstruction of the tracepoints that are in use on the target.
853 You can now exercise direct control over the ways that GDB can
854 affect your program. For instance, you can disallow the setting of
855 breakpoints, so that the program can run continuously (assuming
856 non-stop mode). In addition, the "observer" variable is available
857 to switch all of the different controls; in observer mode, GDB
858 cannot affect the target's behavior at all, which is useful for
859 tasks like diagnosing live systems in the field.
861 * The new convenience variable $_thread holds the number of the
868 Return the address of the Windows Thread Information Block of a given thread.
872 In response to several of the tracepoint packets, the target may now
873 also respond with a number of intermediate `qRelocInsn' request
874 packets before the final result packet, to have GDB handle
875 relocating an instruction to execute at a different address. This
876 is particularly useful for stubs that support fast tracepoints. GDB
877 reports support for this feature in the qSupported packet.
881 List static tracepoint markers in the target program.
885 List static tracepoint markers at a given address in the target
888 qXfer:statictrace:read
890 Read the static trace data collected (by a `collect $_sdata'
891 tracepoint action). The remote stub reports support for this packet
892 to gdb's qSupported query.
896 Send the current settings of GDB's permission flags.
900 Send part of the source (textual) form of a tracepoint definition,
901 which includes location, conditional, and action list.
903 * The source command now accepts a -s option to force searching for the
904 script in the source search path even if the script name specifies
907 * New features in the GDB remote stub, GDBserver
909 - GDBserver now support tracepoints (including fast tracepoints, and
910 static tracepoints). The feature is currently supported by the
911 i386-linux and amd64-linux builds. See the "Tracepoints support
912 in gdbserver" section in the manual for more information.
914 GDBserver JIT compiles the tracepoint's conditional agent
915 expression bytecode into native code whenever possible for low
916 overhead dynamic tracepoints conditionals. For such tracepoints,
917 an expression that examines program state is evaluated when the
918 tracepoint is reached, in order to determine whether to capture
919 trace data. If the condition is simple and false, processing the
920 tracepoint finishes very quickly and no data is gathered.
922 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
923 for static tracepoints support.
925 - GDBserver now supports x86_64 Windows 64-bit debugging.
927 * GDB now sends xmlRegisters= in qSupported packet to indicate that
928 it understands register description.
930 * The --batch flag now disables pagination and queries.
932 * X86 general purpose registers
934 GDB now supports reading/writing byte, word and double-word x86
935 general purpose registers directly. This means you can use, say,
936 $ah or $ax to refer, respectively, to the byte register AH and
937 16-bit word register AX that are actually portions of the 32-bit
938 register EAX or 64-bit register RAX.
940 * The `commands' command now accepts a range of breakpoints to modify.
941 A plain `commands' following a command that creates multiple
942 breakpoints affects all the breakpoints set by that command. This
943 applies to breakpoints set by `rbreak', and also applies when a
944 single `break' command creates multiple breakpoints (e.g.,
945 breakpoints on overloaded c++ functions).
947 * The `rbreak' command now accepts a filename specification as part of
948 its argument, limiting the functions selected by the regex to those
949 in the specified file.
951 * Support for remote debugging Windows and SymbianOS shared libraries
952 from Unix hosts has been improved. Non Windows GDB builds now can
953 understand target reported file names that follow MS-DOS based file
954 system semantics, such as file names that include drive letters and
955 use the backslash character as directory separator. This makes it
956 possible to transparently use the "set sysroot" and "set
957 solib-search-path" on Unix hosts to point as host copies of the
958 target's shared libraries. See the new command "set
959 target-file-system-kind" described below, and the "Commands to
960 specify files" section in the user manual for more information.
964 eval template, expressions...
965 Convert the values of one or more expressions under the control
966 of the string template to a command line, and call it.
968 set target-file-system-kind unix|dos-based|auto
969 show target-file-system-kind
970 Set or show the assumed file system kind for target reported file
973 save breakpoints <filename>
974 Save all current breakpoint definitions to a file suitable for use
975 in a later debugging session. To read the saved breakpoint
976 definitions, use the `source' command.
978 `save tracepoints' is a new alias for `save-tracepoints'. The latter
981 info static-tracepoint-markers
982 Display information about static tracepoint markers in the target.
984 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
985 Define a static tracepoint by probing a marker at the given
986 function, line, address, or marker ID.
990 Enable and disable observer mode.
992 set may-write-registers on|off
993 set may-write-memory on|off
994 set may-insert-breakpoints on|off
995 set may-insert-tracepoints on|off
996 set may-insert-fast-tracepoints on|off
997 set may-interrupt on|off
998 Set individual permissions for GDB effects on the target. Note that
999 some of these settings can have undesirable or surprising
1000 consequences, particularly when changed in the middle of a session.
1001 For instance, disabling the writing of memory can prevent
1002 breakpoints from being inserted, cause single-stepping to fail, or
1003 even crash your program, if you disable after breakpoints have been
1004 inserted. However, GDB should not crash.
1006 set record memory-query on|off
1007 show record memory-query
1008 Control whether to stop the inferior if memory changes caused
1009 by an instruction cannot be recorded.
1014 The disassemble command now supports "start,+length" form of two arguments.
1018 ** GDB now provides a new directory location, called the python directory,
1019 where Python scripts written for GDB can be installed. The location
1020 of that directory is <data-directory>/python, where <data-directory>
1021 is the GDB data directory. For more details, see section `Scripting
1022 GDB using Python' in the manual.
1024 ** The GDB Python API now has access to breakpoints, symbols, symbol
1025 tables, program spaces, inferiors, threads and frame's code blocks.
1026 Additionally, GDB Parameters can now be created from the API, and
1027 manipulated via set/show in the CLI.
1029 ** New functions gdb.target_charset, gdb.target_wide_charset,
1030 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1032 ** New exception gdb.GdbError.
1034 ** Pretty-printers are now also looked up in the current program space.
1036 ** Pretty-printers can now be individually enabled and disabled.
1038 ** GDB now looks for names of Python scripts to auto-load in a
1039 special section named `.debug_gdb_scripts', in addition to looking
1040 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1042 * Tracepoint actions were unified with breakpoint commands. In particular,
1043 there are no longer differences in "info break" output for breakpoints and
1044 tracepoints and the "commands" command can be used for both tracepoints and
1045 regular breakpoints.
1049 ARM Symbian arm*-*-symbianelf*
1051 * D language support.
1052 GDB now supports debugging programs written in the D programming
1055 * GDB now supports the extended ptrace interface for PowerPC which is
1056 available since Linux kernel version 2.6.34. This automatically enables
1057 any hardware breakpoints and additional hardware watchpoints available in
1058 the processor. The old ptrace interface exposes just one hardware
1059 watchpoint and no hardware breakpoints.
1061 * GDB is now able to use the Data Value Compare (DVC) register available on
1062 embedded PowerPC processors to implement in hardware simple watchpoint
1063 conditions of the form:
1065 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1067 This works in native GDB running on Linux kernels with the extended ptrace
1068 interface mentioned above.
1070 *** Changes in GDB 7.1
1074 ** Namespace Support
1076 GDB now supports importing of namespaces in C++. This enables the
1077 user to inspect variables from imported namespaces. Support for
1078 namepace aliasing has also been added. So, if a namespace is
1079 aliased in the current scope (e.g. namepace C=A; ) the user can
1080 print variables using the alias (e.g. (gdb) print C::x).
1084 All known bugs relating to the printing of virtual base class were
1085 fixed. It is now possible to call overloaded static methods using a
1090 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1091 and reinterpret_cast<> are now handled by the C++ expression parser.
1095 Xilinx MicroBlaze microblaze-*-*
1100 Xilinx MicroBlaze microblaze
1103 * Multi-program debugging.
1105 GDB now has support for multi-program (a.k.a. multi-executable or
1106 multi-exec) debugging. This allows for debugging multiple inferiors
1107 simultaneously each running a different program under the same GDB
1108 session. See "Debugging Multiple Inferiors and Programs" in the
1109 manual for more information. This implied some user visible changes
1110 in the multi-inferior support. For example, "info inferiors" now
1111 lists inferiors that are not running yet or that have exited
1112 already. See also "New commands" and "New options" below.
1114 * New tracing features
1116 GDB's tracepoint facility now includes several new features:
1118 ** Trace state variables
1120 GDB tracepoints now include support for trace state variables, which
1121 are variables managed by the target agent during a tracing
1122 experiment. They are useful for tracepoints that trigger each
1123 other, so for instance one tracepoint can count hits in a variable,
1124 and then a second tracepoint has a condition that is true when the
1125 count reaches a particular value. Trace state variables share the
1126 $-syntax of GDB convenience variables, and can appear in both
1127 tracepoint actions and condition expressions. Use the "tvariable"
1128 command to create, and "info tvariables" to view; see "Trace State
1129 Variables" in the manual for more detail.
1133 GDB now includes an option for defining fast tracepoints, which
1134 targets may implement more efficiently, such as by installing a jump
1135 into the target agent rather than a trap instruction. The resulting
1136 speedup can be by two orders of magnitude or more, although the
1137 tradeoff is that some program locations on some target architectures
1138 might not allow fast tracepoint installation, for instance if the
1139 instruction to be replaced is shorter than the jump. To request a
1140 fast tracepoint, use the "ftrace" command, with syntax identical to
1141 the regular trace command.
1143 ** Disconnected tracing
1145 It is now possible to detach GDB from the target while it is running
1146 a trace experiment, then reconnect later to see how the experiment
1147 is going. In addition, a new variable disconnected-tracing lets you
1148 tell the target agent whether to continue running a trace if the
1149 connection is lost unexpectedly.
1153 GDB now has the ability to save the trace buffer into a file, and
1154 then use that file as a target, similarly to you can do with
1155 corefiles. You can select trace frames, print data that was
1156 collected in them, and use tstatus to display the state of the
1157 tracing run at the moment that it was saved. To create a trace
1158 file, use "tsave <filename>", and to use it, do "target tfile
1161 ** Circular trace buffer
1163 You can ask the target agent to handle the trace buffer as a
1164 circular buffer, discarding the oldest trace frames to make room for
1165 newer ones, by setting circular-trace-buffer to on. This feature may
1166 not be available for all target agents.
1171 The disassemble command, when invoked with two arguments, now requires
1172 the arguments to be comma-separated.
1175 The info variables command now displays variable definitions. Files
1176 which only declare a variable are not shown.
1179 The source command is now capable of sourcing Python scripts.
1180 This feature is dependent on the debugger being build with Python
1183 Related to this enhancement is also the introduction of a new command
1184 "set script-extension" (see below).
1186 * New commands (for set/show, see "New options" below)
1188 record save [<FILENAME>]
1189 Save a file (in core file format) containing the process record
1190 execution log for replay debugging at a later time.
1192 record restore <FILENAME>
1193 Restore the process record execution log that was saved at an
1194 earlier time, for replay debugging.
1196 add-inferior [-copies <N>] [-exec <FILENAME>]
1199 clone-inferior [-copies <N>] [ID]
1200 Make a new inferior ready to execute the same program another
1201 inferior has loaded.
1206 maint info program-spaces
1207 List the program spaces loaded into GDB.
1209 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1210 show remote interrupt-sequence
1211 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1212 as the sequence to the remote target in order to interrupt the execution.
1213 Ctrl-C is a default. Some system prefers BREAK which is high level of
1214 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1215 Magic SysRq g. It is BREAK signal and character 'g'.
1217 set remote interrupt-on-connect [on | off]
1218 show remote interrupt-on-connect
1219 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1220 remote target when gdb connects to it. This is needed when you debug
1223 set remotebreak [on | off]
1225 Deprecated. Use "set/show remote interrupt-sequence" instead.
1227 tvariable $NAME [ = EXP ]
1228 Create or modify a trace state variable.
1231 List trace state variables and their values.
1233 delete tvariable $NAME ...
1234 Delete one or more trace state variables.
1237 Evaluate the given expressions without collecting anything into the
1238 trace buffer. (Valid in tracepoint actions only.)
1240 ftrace FN / FILE:LINE / *ADDR
1241 Define a fast tracepoint at the given function, line, or address.
1243 * New expression syntax
1245 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1246 GDB now parses 0b101010 identically with 42.
1250 set follow-exec-mode new|same
1251 show follow-exec-mode
1252 Control whether GDB reuses the same inferior across an exec call or
1253 creates a new one. This is useful to be able to restart the old
1254 executable after the inferior having done an exec call.
1256 set default-collect EXPR, ...
1257 show default-collect
1258 Define a list of expressions to be collected at each tracepoint.
1259 This is a useful way to ensure essential items are not overlooked,
1260 such as registers or a critical global variable.
1262 set disconnected-tracing
1263 show disconnected-tracing
1264 If set to 1, the target is instructed to continue tracing if it
1265 loses its connection to GDB. If 0, the target is to stop tracing
1268 set circular-trace-buffer
1269 show circular-trace-buffer
1270 If set to on, the target is instructed to use a circular trace buffer
1271 and discard the oldest trace frames instead of stopping the trace due
1272 to a full trace buffer. If set to off, the trace stops when the buffer
1273 fills up. Some targets may not support this.
1275 set script-extension off|soft|strict
1276 show script-extension
1277 If set to "off", the debugger does not perform any script language
1278 recognition, and all sourced files are assumed to be GDB scripts.
1279 If set to "soft" (the default), files are sourced according to
1280 filename extension, falling back to GDB scripts if the first
1282 If set to "strict", files are sourced according to filename extension.
1284 set ada trust-PAD-over-XVS on|off
1285 show ada trust-PAD-over-XVS
1286 If off, activate a workaround against a bug in the debugging information
1287 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1288 the GCC sources for more information about the GNAT encoding and
1289 PAD types in particular). It is always safe to set this option to
1290 off, but this introduces a slight performance penalty. The default
1293 * Python API Improvements
1295 ** GDB provides the new class gdb.LazyString. This is useful in
1296 some pretty-printing cases. The new method gdb.Value.lazy_string
1297 provides a simple way to create objects of this type.
1299 ** The fields returned by gdb.Type.fields now have an
1300 `is_base_class' attribute.
1302 ** The new method gdb.Type.range returns the range of an array type.
1304 ** The new method gdb.parse_and_eval can be used to parse and
1305 evaluate an expression.
1307 * New remote packets
1310 Define a trace state variable.
1313 Get the current value of a trace state variable.
1316 Set desired tracing behavior upon disconnection.
1319 Set the trace buffer to be linear or circular.
1322 Get data about the tracepoints currently in use.
1326 Process record now works correctly with hardware watchpoints.
1328 Multiple bug fixes have been made to the mips-irix port, making it
1329 much more reliable. In particular:
1330 - Debugging threaded applications is now possible again. Previously,
1331 GDB would hang while starting the program, or while waiting for
1332 the program to stop at a breakpoint.
1333 - Attaching to a running process no longer hangs.
1334 - An error occurring while loading a core file has been fixed.
1335 - Changing the value of the PC register now works again. This fixes
1336 problems observed when using the "jump" command, or when calling
1337 a function from GDB, or even when assigning a new value to $pc.
1338 - With the "finish" and "return" commands, the return value for functions
1339 returning a small array is now correctly printed.
1340 - It is now possible to break on shared library code which gets executed
1341 during a shared library init phase (code executed while executing
1342 their .init section). Previously, the breakpoint would have no effect.
1343 - GDB is now able to backtrace through the signal handler for
1344 non-threaded programs.
1346 PIE (Position Independent Executable) programs debugging is now supported.
1347 This includes debugging execution of PIC (Position Independent Code) shared
1348 libraries although for that, it should be possible to run such libraries as an
1351 *** Changes in GDB 7.0
1353 * GDB now has an interface for JIT compilation. Applications that
1354 dynamically generate code can create symbol files in memory and register
1355 them with GDB. For users, the feature should work transparently, and
1356 for JIT developers, the interface is documented in the GDB manual in the
1357 "JIT Compilation Interface" chapter.
1359 * Tracepoints may now be conditional. The syntax is as for
1360 breakpoints; either an "if" clause appended to the "trace" command,
1361 or the "condition" command is available. GDB sends the condition to
1362 the target for evaluation using the same bytecode format as is used
1363 for tracepoint actions.
1365 * The disassemble command now supports: an optional /r modifier, print the
1366 raw instructions in hex as well as in symbolic form, and an optional /m
1367 modifier to print mixed source+assembly.
1369 * Process record and replay
1371 In a architecture environment that supports ``process record and
1372 replay'', ``process record and replay'' target can record a log of
1373 the process execution, and replay it with both forward and reverse
1376 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1377 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1378 set execution-direction {forward|reverse}, for targets that support
1381 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1382 feature is available with a native GDB running on kernel version
1385 * GDB now has support for multi-byte and wide character sets on the
1386 target. Strings whose character type is wchar_t, char16_t, or
1387 char32_t are now correctly printed. GDB supports wide- and unicode-
1388 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1389 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1390 `printf'. This feature requires iconv to work properly; if your
1391 system does not have a working iconv, GDB can use GNU libiconv. See
1392 the installation instructions for more information.
1394 * GDB now supports automatic retrieval of shared library files from
1395 remote targets. To use this feature, specify a system root that begins
1396 with the `remote:' prefix, either via the `set sysroot' command or via
1397 the `--with-sysroot' configure-time option.
1399 * "info sharedlibrary" now takes an optional regex of libraries to show,
1400 and it now reports if a shared library has no debugging information.
1402 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1403 now complete on file names.
1405 * When completing in expressions, gdb will attempt to limit
1406 completions to allowable structure or union fields, where appropriate.
1407 For instance, consider:
1409 # struct example { int f1; double f2; };
1410 # struct example variable;
1413 If the user types TAB at the end of this command line, the available
1414 completions will be "f1" and "f2".
1416 * Inlined functions are now supported. They show up in backtraces, and
1417 the "step", "next", and "finish" commands handle them automatically.
1419 * GDB now supports the token-splicing (##) and stringification (#)
1420 operators when expanding macros. It also supports variable-arity
1423 * GDB now supports inspecting extra signal information, exported by
1424 the new $_siginfo convenience variable. The feature is currently
1425 implemented on linux ARM, i386 and amd64.
1427 * GDB can now display the VFP floating point registers and NEON vector
1428 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1429 can provide these registers (requires Linux 2.6.30 or later). Remote
1430 and simulator targets may also provide them.
1432 * New remote packets
1435 Search memory for a sequence of bytes.
1438 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1439 operation over reliable transport links. Use of this packet is
1440 controlled by the `set remote noack-packet' command.
1443 Kill the process with the specified process ID. Use this in preference
1444 to `k' when multiprocess protocol extensions are supported.
1447 Obtains additional operating system information
1451 Read or write additional signal information.
1453 * Removed remote protocol undocumented extension
1455 An undocumented extension to the remote protocol's `S' stop reply
1456 packet that permited the stub to pass a process id was removed.
1457 Remote servers should use the `T' stop reply packet instead.
1459 * GDB now supports multiple function calling conventions according to the
1460 DWARF-2 DW_AT_calling_convention function attribute.
1462 * The SH target utilizes the aforementioned change to distinguish between gcc
1463 and Renesas calling convention. It also adds the new CLI commands
1464 `set/show sh calling-convention'.
1466 * GDB can now read compressed debug sections, as produced by GNU gold
1467 with the --compress-debug-sections=zlib flag.
1469 * 64-bit core files are now supported on AIX.
1471 * Thread switching is now supported on Tru64.
1473 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1474 which will be allocated using malloc later in program execution.
1476 * The qXfer:libraries:read remote procotol packet now allows passing a
1477 list of section offsets.
1479 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1480 conditions handling signals delivered during attach or thread creation
1481 have also been fixed.
1483 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1484 From the user's standpoint, all unqualified instances of True and False
1485 are treated as the standard definitions, regardless of context.
1487 * GDB now parses C++ symbol and type names more flexibly. For
1490 template<typename T> class C { };
1493 GDB will now correctly handle all of:
1495 ptype C<char const *>
1496 ptype C<char const*>
1497 ptype C<const char *>
1498 ptype C<const char*>
1500 * New features in the GDB remote stub, gdbserver
1502 - The "--wrapper" command-line argument tells gdbserver to use a
1503 wrapper program to launch programs for debugging.
1505 - On PowerPC and S/390 targets, it is now possible to use a single
1506 gdbserver executable to debug both 32-bit and 64-bit programs.
1507 (This requires gdbserver itself to be built as a 64-bit executable.)
1509 - gdbserver uses the new noack protocol mode for TCP connections to
1510 reduce communications latency, if also supported and enabled in GDB.
1512 - Support for the sparc64-linux-gnu target is now included in
1515 - The amd64-linux build of gdbserver now supports debugging both
1516 32-bit and 64-bit programs.
1518 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1519 now support hardware watchpoints, and will use them automatically
1524 GDB now has support for scripting using Python. Whether this is
1525 available is determined at configure time.
1527 New GDB commands can now be written in Python.
1529 * Ada tasking support
1531 Ada tasks can now be inspected in GDB. The following commands have
1535 Print the list of Ada tasks.
1537 Print detailed information about task number N.
1539 Print the task number of the current task.
1541 Switch the context of debugging to task number N.
1543 * Support for user-defined prefixed commands. The "define" command can
1544 add new commands to existing prefixes, e.g. "target".
1546 * Multi-inferior, multi-process debugging.
1548 GDB now has generalized support for multi-inferior debugging. See
1549 "Debugging Multiple Inferiors" in the manual for more information.
1550 Although availability still depends on target support, the command
1551 set is more uniform now. The GNU/Linux specific multi-forks support
1552 has been migrated to this new framework. This implied some user
1553 visible changes; see "New commands" and also "Removed commands"
1556 * Target descriptions can now describe the target OS ABI. See the
1557 "Target Description Format" section in the user manual for more
1560 * Target descriptions can now describe "compatible" architectures
1561 to indicate that the target can execute applications for a different
1562 architecture in addition to those for the main target architecture.
1563 See the "Target Description Format" section in the user manual for
1566 * Multi-architecture debugging.
1568 GDB now includes general supports for debugging applications on
1569 hybrid systems that use more than one single processor architecture
1570 at the same time. Each such hybrid architecture still requires
1571 specific support to be added. The only hybrid architecture supported
1572 in this version of GDB is the Cell Broadband Engine.
1574 * GDB now supports integrated debugging of Cell/B.E. applications that
1575 use both the PPU and SPU architectures. To enable support for hybrid
1576 Cell/B.E. debugging, you need to configure GDB to support both the
1577 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1578 --enable-targets configure option.
1580 * Non-stop mode debugging.
1582 For some targets, GDB now supports an optional mode of operation in
1583 which you can examine stopped threads while other threads continue
1584 to execute freely. This is referred to as non-stop mode, with the
1585 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1586 section in the user manual for more information.
1588 To be able to support remote non-stop debugging, a remote stub needs
1589 to implement the non-stop mode remote protocol extensions, as
1590 described in the "Remote Non-Stop" section of the user manual. The
1591 GDB remote stub, gdbserver, has been adjusted to support these
1592 extensions on linux targets.
1594 * New commands (for set/show, see "New options" below)
1596 catch syscall [NAME(S) | NUMBER(S)]
1597 Catch system calls. Arguments, which should be names of system
1598 calls or their numbers, mean catch only those syscalls. Without
1599 arguments, every syscall will be caught. When the inferior issues
1600 any of the specified syscalls, GDB will stop and announce the system
1601 call, both when it is called and when its call returns. This
1602 feature is currently available with a native GDB running on the
1603 Linux Kernel, under the following architectures: x86, x86_64,
1604 PowerPC and PowerPC64.
1606 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1608 Search memory for a sequence of bytes.
1610 maint set python print-stack
1611 maint show python print-stack
1612 Show a stack trace when an error is encountered in a Python script.
1615 Invoke CODE by passing it to the Python interpreter.
1620 These allow macros to be defined, undefined, and listed
1624 Show operating system information about processes.
1627 List the inferiors currently under GDB's control.
1630 Switch focus to inferior number NUM.
1633 Detach from inferior number NUM.
1636 Kill inferior number NUM.
1640 set spu stop-on-load
1641 show spu stop-on-load
1642 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1644 set spu auto-flush-cache
1645 show spu auto-flush-cache
1646 Control whether to automatically flush the software-managed cache
1647 during Cell/B.E. debugging.
1649 set sh calling-convention
1650 show sh calling-convention
1651 Control the calling convention used when calling SH target functions.
1654 show debug timestamp
1655 Control display of timestamps with GDB debugging output.
1657 set disassemble-next-line
1658 show disassemble-next-line
1659 Control display of disassembled source lines or instructions when
1662 set remote noack-packet
1663 show remote noack-packet
1664 Set/show the use of remote protocol QStartNoAckMode packet. See above
1665 under "New remote packets."
1667 set remote query-attached-packet
1668 show remote query-attached-packet
1669 Control use of remote protocol `qAttached' (query-attached) packet.
1671 set remote read-siginfo-object
1672 show remote read-siginfo-object
1673 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1676 set remote write-siginfo-object
1677 show remote write-siginfo-object
1678 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1681 set remote reverse-continue
1682 show remote reverse-continue
1683 Control use of remote protocol 'bc' (reverse-continue) packet.
1685 set remote reverse-step
1686 show remote reverse-step
1687 Control use of remote protocol 'bs' (reverse-step) packet.
1689 set displaced-stepping
1690 show displaced-stepping
1691 Control displaced stepping mode. Displaced stepping is a way to
1692 single-step over breakpoints without removing them from the debuggee.
1693 Also known as "out-of-line single-stepping".
1696 show debug displaced
1697 Control display of debugging info for displaced stepping.
1699 maint set internal-error
1700 maint show internal-error
1701 Control what GDB does when an internal error is detected.
1703 maint set internal-warning
1704 maint show internal-warning
1705 Control what GDB does when an internal warning is detected.
1710 Use a wrapper program to launch programs for debugging.
1712 set multiple-symbols (all|ask|cancel)
1713 show multiple-symbols
1714 The value of this variable can be changed to adjust the debugger behavior
1715 when an expression or a breakpoint location contains an ambiguous symbol
1716 name (an overloaded function name, for instance).
1718 set breakpoint always-inserted
1719 show breakpoint always-inserted
1720 Keep breakpoints always inserted in the target, as opposed to inserting
1721 them when resuming the target, and removing them when the target stops.
1722 This option can improve debugger performance on slow remote targets.
1724 set arm fallback-mode (arm|thumb|auto)
1725 show arm fallback-mode
1726 set arm force-mode (arm|thumb|auto)
1728 These commands control how ARM GDB determines whether instructions
1729 are ARM or Thumb. The default for both settings is auto, which uses
1730 the current CPSR value for instructions without symbols; previous
1731 versions of GDB behaved as if "set arm fallback-mode arm".
1733 set disable-randomization
1734 show disable-randomization
1735 Standalone programs run with the virtual address space randomization enabled
1736 by default on some platforms. This option keeps the addresses stable across
1737 multiple debugging sessions.
1741 Control whether other threads are stopped or not when some thread hits
1746 Requests that asynchronous execution is enabled in the target, if available.
1747 In this case, it's possible to resume target in the background, and interact
1748 with GDB while the target is running. "show target-async" displays the
1749 current state of asynchronous execution of the target.
1751 set target-wide-charset
1752 show target-wide-charset
1753 The target-wide-charset is the name of the character set that GDB
1754 uses when printing characters whose type is wchar_t.
1756 set tcp auto-retry (on|off)
1758 set tcp connect-timeout
1759 show tcp connect-timeout
1760 These commands allow GDB to retry failed TCP connections to a remote stub
1761 with a specified timeout period; this is useful if the stub is launched
1762 in parallel with GDB but may not be ready to accept connections immediately.
1764 set libthread-db-search-path
1765 show libthread-db-search-path
1766 Control list of directories which GDB will search for appropriate
1769 set schedule-multiple (on|off)
1770 show schedule-multiple
1771 Allow GDB to resume all threads of all processes or only threads of
1772 the current process.
1776 Use more aggressive caching for accesses to the stack. This improves
1777 performance of remote debugging (particularly backtraces) without
1778 affecting correctness.
1780 set interactive-mode (on|off|auto)
1781 show interactive-mode
1782 Control whether GDB runs in interactive mode (on) or not (off).
1783 When in interactive mode, GDB waits for the user to answer all
1784 queries. Otherwise, GDB does not wait and assumes the default
1785 answer. When set to auto (the default), GDB determines which
1786 mode to use based on the stdin settings.
1791 For program forks, this is replaced by the new more generic `info
1792 inferiors' command. To list checkpoints, you can still use the
1793 `info checkpoints' command, which was an alias for the `info forks'
1797 Replaced by the new `inferior' command. To switch between
1798 checkpoints, you can still use the `restart' command, which was an
1799 alias for the `fork' command.
1802 This is removed, since some targets don't have a notion of
1803 processes. To switch between processes, you can still use the
1804 `inferior' command using GDB's own inferior number.
1807 For program forks, this is replaced by the new more generic `kill
1808 inferior' command. To delete a checkpoint, you can still use the
1809 `delete checkpoint' command, which was an alias for the `delete
1813 For program forks, this is replaced by the new more generic `detach
1814 inferior' command. To detach a checkpoint, you can still use the
1815 `detach checkpoint' command, which was an alias for the `detach
1818 * New native configurations
1820 x86/x86_64 Darwin i[34567]86-*-darwin*
1822 x86_64 MinGW x86_64-*-mingw*
1826 Lattice Mico32 lm32-*
1827 x86 DICOS i[34567]86-*-dicos*
1828 x86_64 DICOS x86_64-*-dicos*
1831 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1832 (mingw32ce) debugging.
1838 These commands were actually not implemented on any target.
1840 *** Changes in GDB 6.8
1842 * New native configurations
1844 NetBSD/hppa hppa*-*netbsd*
1845 Xtensa GNU/Linux xtensa*-*-linux*
1849 NetBSD/hppa hppa*-*-netbsd*
1850 Xtensa GNU/Lunux xtensa*-*-linux*
1852 * Change in command line behavior -- corefiles vs. process ids.
1854 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1855 attaching to process NUMBER fails, GDB no longer attempts to open a
1856 core file named NUMBER. Attaching to a program using the -c option
1857 is no longer supported. Instead, use the '-p' or '--pid' options.
1859 * GDB can now be built as a native debugger for debugging Windows x86
1860 (mingw32) Portable Executable (PE) programs.
1862 * Pending breakpoints no longer change their number when their address
1865 * GDB now supports breakpoints with multiple locations,
1866 including breakpoints on C++ constructors, inside C++ templates,
1867 and in inlined functions.
1869 * GDB's ability to debug optimized code has been improved. GDB more
1870 accurately identifies function bodies and lexical blocks that occupy
1871 more than one contiguous range of addresses.
1873 * Target descriptions can now describe registers for PowerPC.
1875 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1876 registers on PowerPC targets.
1878 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1879 targets even when the libthread_db library is not available.
1881 * The GDB remote stub, gdbserver, now supports the new file transfer
1882 commands (remote put, remote get, and remote delete).
1884 * The GDB remote stub, gdbserver, now supports run and attach in
1885 extended-remote mode.
1887 * hppa*64*-*-hpux11* target broken
1888 The debugger is unable to start a program and fails with the following
1889 error: "Error trying to get information about dynamic linker".
1890 The gdb-6.7 release is also affected.
1892 * GDB now supports the --enable-targets= configure option to allow
1893 building a single GDB executable that supports multiple remote
1894 target architectures.
1896 * GDB now supports debugging C and C++ programs which use the
1897 Decimal Floating Point extension. In addition, the PowerPC target
1898 now has a set of pseudo-registers to inspect decimal float values
1899 stored in two consecutive float registers.
1901 * The -break-insert MI command can optionally create pending
1904 * Improved support for debugging Ada
1905 Many improvements to the Ada language support have been made. These
1907 - Better support for Ada2005 interface types
1908 - Improved handling of arrays and slices in general
1909 - Better support for Taft-amendment types
1910 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1912 - Improved command completion in Ada
1915 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1920 set print frame-arguments (all|scalars|none)
1921 show print frame-arguments
1922 The value of this variable can be changed to control which argument
1923 values should be printed by the debugger when displaying a frame.
1928 Transfer files to and from a remote target, and delete remote files.
1935 Transfer files to and from a remote target, and delete remote files.
1937 * New remote packets
1944 Open, close, read, write, and delete files on the remote system.
1947 Attach to an existing process on the remote system, in extended-remote
1951 Run a new process on the remote system, in extended-remote mode.
1953 *** Changes in GDB 6.7
1955 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1956 bfd, libiberty and opcodes, as revealed by static analysis donated by
1957 Coverity, Inc. (http://scan.coverity.com).
1959 * When looking up multiply-defined global symbols, GDB will now prefer the
1960 symbol definition in the current shared library if it was built using the
1961 -Bsymbolic linker option.
1963 * When the Text User Interface (TUI) is not configured, GDB will now
1964 recognize the -tui command-line option and print a message that the TUI
1967 * The GDB remote stub, gdbserver, now has lower overhead for high
1968 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1970 * GDB for MIPS targets now autodetects whether a remote target provides
1971 32-bit or 64-bit register values.
1973 * Support for C++ member pointers has been improved.
1975 * GDB now understands XML target descriptions, which specify the
1976 target's overall architecture. GDB can read a description from
1977 a local file or over the remote serial protocol.
1979 * Vectors of single-byte data use a new integer type which is not
1980 automatically displayed as character or string data.
1982 * The /s format now works with the print command. It displays
1983 arrays of single-byte integers and pointers to single-byte integers
1986 * Target descriptions can now describe target-specific registers,
1987 for architectures which have implemented the support (currently
1988 only ARM, M68K, and MIPS).
1990 * GDB and the GDB remote stub, gdbserver, now support the XScale
1993 * The GDB remote stub, gdbserver, has been updated to support
1994 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1995 has been rewritten to use the standard GDB remote protocol.
1997 * GDB can now step into C++ functions which are called through thunks.
1999 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2001 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2002 layout. It also supports a TextSeg= and DataSeg= response when only
2003 segment base addresses (rather than offsets) are available.
2005 * The /i format now outputs any trailing branch delay slot instructions
2006 immediately following the last instruction within the count specified.
2008 * The GDB remote protocol "T" stop reply packet now supports a
2009 "library" response. Combined with the new "qXfer:libraries:read"
2010 packet, this response allows GDB to debug shared libraries on targets
2011 where the operating system manages the list of loaded libraries (e.g.
2012 Windows and SymbianOS).
2014 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2015 (DLLs) on Windows and Windows CE targets.
2017 * GDB now supports a faster verification that a .debug file matches its binary
2018 according to its build-id signature, if the signature is present.
2024 Enable or disable hardware flow control (RTS/CTS) on the serial port
2025 when debugging using remote targets.
2027 set mem inaccessible-by-default
2028 show mem inaccessible-by-default
2029 If the target supplies a memory map, for instance via the remote
2030 protocol's "qXfer:memory-map:read" packet, setting this variable
2031 prevents GDB from accessing memory outside the memory map. This
2032 is useful for targets with memory mapped registers or which react
2033 badly to accesses of unmapped address space.
2035 set breakpoint auto-hw
2036 show breakpoint auto-hw
2037 If the target supplies a memory map, for instance via the remote
2038 protocol's "qXfer:memory-map:read" packet, setting this variable
2039 lets GDB use hardware breakpoints automatically for memory regions
2040 where it can not use software breakpoints. This covers both the
2041 "break" command and internal breakpoints used for other commands
2042 including "next" and "finish".
2045 catch exception unhandled
2046 Stop the program execution when Ada exceptions are raised.
2049 Stop the program execution when an Ada assertion failed.
2053 Set an alternate system root for target files. This is a more
2054 general version of "set solib-absolute-prefix", which is now
2055 an alias to "set sysroot".
2058 Provide extended SPU facility status information. This set of
2059 commands is available only when debugging the Cell/B.E. SPU
2062 * New native configurations
2064 OpenBSD/sh sh*-*openbsd*
2067 unset tdesc filename
2069 Use the specified local file as an XML target description, and do
2070 not query the target for its built-in description.
2074 OpenBSD/sh sh*-*-openbsd*
2075 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2076 Toshiba Media Processor mep-elf
2078 * New remote packets
2081 Ignore the specified signals; pass them directly to the debugged program
2082 without stopping other threads or reporting them to GDB.
2084 qXfer:features:read:
2085 Read an XML target description from the target, which describes its
2090 Read or write contents of an spufs file on the target system. These
2091 packets are available only on the Cell/B.E. SPU architecture.
2093 qXfer:libraries:read:
2094 Report the loaded shared libraries. Combined with new "T" packet
2095 response, this packet allows GDB to debug shared libraries on
2096 targets where the operating system manages the list of loaded
2097 libraries (e.g. Windows and SymbianOS).
2101 Support for these obsolete configurations has been removed.
2109 i[34567]86-*-lynxos*
2110 i[34567]86-*-netware*
2111 i[34567]86-*-sco3.2v5*
2112 i[34567]86-*-sco3.2v4*
2114 i[34567]86-*-sysv4.2*
2117 i[34567]86-*-unixware2*
2118 i[34567]86-*-unixware*
2127 * Other removed features
2134 Various m68k-only ROM monitors.
2141 Various Renesas ROM monitors and debugging interfaces for SH and
2146 Support for a Macraigor serial interface to on-chip debugging.
2147 GDB does not directly support the newer parallel or USB
2152 A debug information format. The predecessor to DWARF 2 and
2153 DWARF 3, which are still supported.
2155 Support for the HP aCC compiler on HP-UX/PA-RISC
2157 SOM-encapsulated symbolic debugging information, automatic
2158 invocation of pxdb, and the aCC custom C++ ABI. This does not
2159 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2160 with aCC can still be debugged on an assembly level.
2162 MIPS ".pdr" sections
2164 A MIPS-specific format used to describe stack frame layout
2165 in debugging information.
2169 GDB could work with an older version of Guile to debug
2170 the interpreter and Scheme programs running in it.
2172 set mips stack-arg-size
2173 set mips saved-gpreg-size
2175 Use "set mips abi" to control parameter passing for MIPS.
2177 *** Changes in GDB 6.6
2182 Cell Broadband Engine SPU spu-elf
2184 * GDB can now be configured as a cross-debugger targeting native Windows
2185 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2186 running on a Windows system over TCP/IP to debug Windows programs.
2188 * The GDB remote stub, gdbserver, has been updated to support Windows and
2189 Cygwin debugging. Both single-threaded and multi-threaded programs are
2192 * The "set trust-readonly-sections" command works again. This command was
2193 broken in GDB 6.3, 6.4, and 6.5.
2195 * The "load" command now supports writing to flash memory, if the remote
2196 stub provides the required support.
2198 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2199 longer requires symbolic debug information (e.g. DWARF-2).
2204 unset substitute-path
2205 show substitute-path
2206 Manage a list of substitution rules that GDB uses to rewrite the name
2207 of the directories where the sources are located. This can be useful
2208 for instance when the sources were moved to a different location
2209 between compilation and debugging.
2213 Print each CLI command as it is executed. Each command is prefixed with
2214 a number of `+' symbols representing the nesting depth.
2215 The source command now has a `-v' option to enable the same feature.
2219 The ARM Demon monitor support (RDP protocol, "target rdp").
2221 Kernel Object Display, an embedded debugging feature which only worked with
2222 an obsolete version of Cisco IOS.
2224 The 'set download-write-size' and 'show download-write-size' commands.
2226 * New remote packets
2229 Tell a stub about GDB client features, and request remote target features.
2230 The first feature implemented is PacketSize, which allows the target to
2231 specify the size of packets it can handle - to minimize the number of
2232 packets required and improve performance when connected to a remote
2236 Fetch an OS auxilliary vector from the remote stub. This packet is a
2237 more efficient replacement for qPart:auxv:read.
2239 qXfer:memory-map:read:
2240 Fetch a memory map from the remote stub, including information about
2241 RAM, ROM, and flash memory devices.
2246 Erase and program a flash memory device.
2248 * Removed remote packets
2251 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2252 used it, and only gdbserver implemented it.
2254 *** Changes in GDB 6.5
2258 Renesas M32C/M16C m32c-elf
2260 Morpho Technologies ms1 ms1-elf
2264 init-if-undefined Initialize a convenience variable, but
2265 only if it doesn't already have a value.
2267 The following commands are presently only implemented for native GNU/Linux:
2269 checkpoint Save a snapshot of the program state.
2271 restart <n> Return the program state to a
2272 previously saved state.
2274 info checkpoints List currently saved checkpoints.
2276 delete-checkpoint <n> Delete a previously saved checkpoint.
2278 set|show detach-on-fork Tell gdb whether to detach from a newly
2279 forked process, or to keep debugging it.
2281 info forks List forks of the user program that
2282 are available to be debugged.
2284 fork <n> Switch to debugging one of several
2285 forks of the user program that are
2286 available to be debugged.
2288 delete-fork <n> Delete a fork from the list of forks
2289 that are available to be debugged (and
2290 kill the forked process).
2292 detach-fork <n> Delete a fork from the list of forks
2293 that are available to be debugged (and
2294 allow the process to continue).
2298 Morpho Technologies ms2 ms1-elf
2300 * Improved Windows host support
2302 GDB now builds as a cross debugger hosted on i686-mingw32, including
2303 native console support, and remote communications using either
2304 network sockets or serial ports.
2306 * Improved Modula-2 language support
2308 GDB can now print most types in the Modula-2 syntax. This includes:
2309 basic types, set types, record types, enumerated types, range types,
2310 pointer types and ARRAY types. Procedure var parameters are correctly
2311 printed and hexadecimal addresses and character constants are also
2312 written in the Modula-2 syntax. Best results can be obtained by using
2313 GNU Modula-2 together with the -gdwarf-2 command line option.
2317 The ARM rdi-share module.
2319 The Netware NLM debug server.
2321 *** Changes in GDB 6.4
2323 * New native configurations
2325 OpenBSD/arm arm*-*-openbsd*
2326 OpenBSD/mips64 mips64-*-openbsd*
2330 Morpho Technologies ms1 ms1-elf
2332 * New command line options
2334 --batch-silent As for --batch, but totally silent.
2335 --return-child-result The debugger will exist with the same value
2336 the child (debugged) program exited with.
2337 --eval-command COMMAND, -ex COMMAND
2338 Execute a single GDB CLI command. This may be
2339 specified multiple times and in conjunction
2340 with the --command (-x) option.
2342 * Deprecated commands removed
2344 The following commands, that were deprecated in 2000, have been
2348 set|show arm disassembly-flavor set|show arm disassembler
2349 othernames set arm disassembler
2350 set|show remotedebug set|show debug remote
2351 set|show archdebug set|show debug arch
2352 set|show eventdebug set|show debug event
2355 * New BSD user-level threads support
2357 It is now possible to debug programs using the user-level threads
2358 library on OpenBSD and FreeBSD. Currently supported (target)
2361 FreeBSD/amd64 x86_64-*-freebsd*
2362 FreeBSD/i386 i386-*-freebsd*
2363 OpenBSD/i386 i386-*-openbsd*
2365 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2366 are not yet supported.
2368 * New support for Matsushita MN10300 w/sim added
2369 (Work in progress). mn10300-elf.
2371 * REMOVED configurations and files
2373 VxWorks and the XDR protocol *-*-vxworks
2374 Motorola MCORE mcore-*-*
2375 National Semiconductor NS32000 ns32k-*-*
2377 * New "set print array-indexes" command
2379 After turning this setting "on", GDB prints the index of each element
2380 when displaying arrays. The default is "off" to preserve the previous
2383 * VAX floating point support
2385 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2387 * User-defined command support
2389 In addition to using $arg0..$arg9 for argument passing, it is now possible
2390 to use $argc to determine now many arguments have been passed. See the
2391 section on user-defined commands in the user manual for more information.
2393 *** Changes in GDB 6.3:
2395 * New command line option
2397 GDB now accepts -l followed by a number to set the timeout for remote
2400 * GDB works with GCC -feliminate-dwarf2-dups
2402 GDB now supports a more compact representation of DWARF-2 debug
2403 information using DW_FORM_ref_addr references. These are produced
2404 by GCC with the option -feliminate-dwarf2-dups and also by some
2405 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2406 to use -feliminate-dwarf2-dups.
2408 * Internationalization
2410 When supported by the host system, GDB will be built with
2411 internationalization (libintl). The task of marking up the sources is
2412 continued, we're looking forward to our first translation.
2416 Initial support for debugging programs compiled with the GNAT
2417 implementation of the Ada programming language has been integrated
2418 into GDB. In this release, support is limited to expression evaluation.
2420 * New native configurations
2422 GNU/Linux/m32r m32r-*-linux-gnu
2426 GDB's remote protocol now includes support for the 'p' packet. This
2427 packet is used to fetch individual registers from a remote inferior.
2429 * END-OF-LIFE registers[] compatibility module
2431 GDB's internal register infrastructure has been completely rewritten.
2432 The new infrastructure making possible the implementation of key new
2433 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2436 GDB 6.3 will be the last release to include the the registers[]
2437 compatibility module that allowed out-of-date configurations to
2438 continue to work. This change directly impacts the following
2448 powerpc bdm protocol
2450 Unless there is activity to revive these configurations, they will be
2451 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2453 * OBSOLETE configurations and files
2455 Configurations that have been declared obsolete in this release have
2456 been commented out. Unless there is activity to revive these
2457 configurations, the next release of GDB will have their sources
2458 permanently REMOVED.
2467 *** Changes in GDB 6.2.1:
2469 * MIPS `break main; run' gave an heuristic-fence-post warning
2471 When attempting to run even a simple program, a warning about
2472 heuristic-fence-post being hit would be reported. This problem has
2475 * MIPS IRIX 'long double' crashed GDB
2477 When examining a long double variable, GDB would get a segmentation
2478 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2479 IRIX long double values).
2483 A bug in the VAX stack code was causing problems with the "next"
2484 command. This problem has been fixed.
2486 *** Changes in GDB 6.2:
2488 * Fix for ``many threads''
2490 On GNU/Linux systems that use the NPTL threads library, a program
2491 rapidly creating and deleting threads would confuse GDB leading to the
2494 ptrace: No such process.
2495 thread_db_get_info: cannot get thread info: generic error
2497 This problem has been fixed.
2499 * "-async" and "-noasync" options removed.
2501 Support for the broken "-noasync" option has been removed (it caused
2504 * New ``start'' command.
2506 This command runs the program until the begining of the main procedure.
2508 * New BSD Kernel Data Access Library (libkvm) interface
2510 Using ``target kvm'' it is now possible to debug kernel core dumps and
2511 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2512 platforms. Currently supported (native-only) configurations are:
2514 FreeBSD/amd64 x86_64-*-freebsd*
2515 FreeBSD/i386 i?86-*-freebsd*
2516 NetBSD/i386 i?86-*-netbsd*
2517 NetBSD/m68k m68*-*-netbsd*
2518 NetBSD/sparc sparc-*-netbsd*
2519 OpenBSD/amd64 x86_64-*-openbsd*
2520 OpenBSD/i386 i?86-*-openbsd*
2521 OpenBSD/m68k m68*-openbsd*
2522 OpenBSD/sparc sparc-*-openbsd*
2524 * Signal trampoline code overhauled
2526 Many generic problems with GDB's signal handling code have been fixed.
2527 These include: backtraces through non-contiguous stacks; recognition
2528 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2529 call; backtrace through a signal trampoline; step into and out of
2530 signal handlers; and single-stepping in the signal trampoline.
2532 Please note that kernel bugs are a limiting factor here. These
2533 features have been shown to work on an s390 GNU/Linux system that
2534 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2536 * Cygwin support for DWARF 2 added.
2538 * New native configurations
2540 GNU/Linux/hppa hppa*-*-linux*
2541 OpenBSD/hppa hppa*-*-openbsd*
2542 OpenBSD/m68k m68*-*-openbsd*
2543 OpenBSD/m88k m88*-*-openbsd*
2544 OpenBSD/powerpc powerpc-*-openbsd*
2545 NetBSD/vax vax-*-netbsd*
2546 OpenBSD/vax vax-*-openbsd*
2548 * END-OF-LIFE frame compatibility module
2550 GDB's internal frame infrastructure has been completely rewritten.
2551 The new infrastructure making it possible to support key new features
2552 including DWARF 2 Call Frame Information. To aid in the task of
2553 migrating old configurations to this new infrastructure, a
2554 compatibility module, that allowed old configurations to continue to
2555 work, was also included.
2557 GDB 6.2 will be the last release to include this frame compatibility
2558 module. This change directly impacts the following configurations:
2568 Unless there is activity to revive these configurations, they will be
2569 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2571 * REMOVED configurations and files
2573 Sun 3, running SunOS 3 m68*-*-sunos3*
2574 Sun 3, running SunOS 4 m68*-*-sunos4*
2575 Sun 2, running SunOS 3 m68000-*-sunos3*
2576 Sun 2, running SunOS 4 m68000-*-sunos4*
2577 Motorola 680x0 running LynxOS m68*-*-lynxos*
2578 AT&T 3b1/Unix pc m68*-att-*
2579 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2580 decstation mips-dec-* mips-little-*
2581 riscos mips-*-riscos* mips-*-sysv*
2582 sonymips mips-sony-*
2583 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2585 *** Changes in GDB 6.1.1:
2587 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2589 The TUI (Text-mode User Interface) is now built as part of a default
2590 GDB configuration. It is enabled by either selecting the TUI with the
2591 command line option "-i=tui" or by running the separate "gdbtui"
2592 program. For more information on the TUI, see the manual "Debugging
2595 * Pending breakpoint support (also included in GDB 6.1)
2597 Support has been added to allow you to specify breakpoints in shared
2598 libraries that have not yet been loaded. If a breakpoint location
2599 cannot be found, and the "breakpoint pending" option is set to auto,
2600 GDB queries you if you wish to make the breakpoint pending on a future
2601 shared-library load. If and when GDB resolves the breakpoint symbol,
2602 the pending breakpoint is removed as one or more regular breakpoints
2605 Pending breakpoints are very useful for GCJ Java debugging.
2607 * Fixed ISO-C build problems
2609 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2610 non ISO-C code that stopped them being built using a more strict ISO-C
2611 compiler (e.g., IBM's C compiler).
2613 * Fixed build problem on IRIX 5
2615 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2616 wasn't able to compile compile on an IRIX 5 system.
2618 * Added execute permission to gdb/gdbserver/configure
2620 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2621 permission. This bug would cause configure to fail on a number of
2622 systems (Solaris, IRIX). Ref: server/519.
2624 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2626 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2627 has been updated to use constant array sizes.
2629 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2631 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2632 its generated DWARF Call Frame Info. This encoding was causing GDB to
2633 panic, that panic has been fixed. Ref: gdb/1628.
2635 * Fixed a problem when examining parameters in shared library code.
2637 When examining parameters in optimized shared library code generated
2638 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2639 not available''. GDB now correctly displays the variable's value.
2641 *** Changes in GDB 6.1:
2643 * Removed --with-mmalloc
2645 Support for the mmalloc memory manager has been removed, as it
2646 conflicted with the internal gdb byte cache.
2648 * Changes in AMD64 configurations
2650 The AMD64 target now includes the %cs and %ss registers. As a result
2651 the AMD64 remote protocol has changed; this affects the floating-point
2652 and SSE registers. If you rely on those registers for your debugging,
2653 you should upgrade gdbserver on the remote side.
2655 * Revised SPARC target
2657 The SPARC target has been completely revised, incorporating the
2658 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2659 support for LynxOS and SunOS 4 has been dropped. Calling functions
2660 from within GDB on operating systems with a non-executable stack
2661 (Solaris, OpenBSD) now works.
2665 GDB has a new C++ demangler which does a better job on the mangled
2666 names generated by current versions of g++. It also runs faster, so
2667 with this and other changes gdb should now start faster on large C++
2670 * DWARF 2 Location Expressions
2672 GDB support for location expressions has been extended to support function
2673 arguments and frame bases. Older versions of GDB could crash when they
2676 * C++ nested types and namespaces
2678 GDB's support for nested types and namespaces in C++ has been
2679 improved, especially if you use the DWARF 2 debugging format. (This
2680 is the default for recent versions of GCC on most platforms.)
2681 Specifically, if you have a class "Inner" defined within a class or
2682 namespace "Outer", then GDB realizes that the class's name is
2683 "Outer::Inner", not simply "Inner". This should greatly reduce the
2684 frequency of complaints about not finding RTTI symbols. In addition,
2685 if you are stopped at inside of a function defined within a namespace,
2686 GDB modifies its name lookup accordingly.
2688 * New native configurations
2690 NetBSD/amd64 x86_64-*-netbsd*
2691 OpenBSD/amd64 x86_64-*-openbsd*
2692 OpenBSD/alpha alpha*-*-openbsd*
2693 OpenBSD/sparc sparc-*-openbsd*
2694 OpenBSD/sparc64 sparc64-*-openbsd*
2696 * New debugging protocols
2698 M32R with SDI protocol m32r-*-elf*
2700 * "set prompt-escape-char" command deleted.
2702 The command "set prompt-escape-char" has been deleted. This command,
2703 and its very obscure effet on GDB's prompt, was never documented,
2704 tested, nor mentioned in the NEWS file.
2706 * OBSOLETE configurations and files
2708 Configurations that have been declared obsolete in this release have
2709 been commented out. Unless there is activity to revive these
2710 configurations, the next release of GDB will have their sources
2711 permanently REMOVED.
2713 Sun 3, running SunOS 3 m68*-*-sunos3*
2714 Sun 3, running SunOS 4 m68*-*-sunos4*
2715 Sun 2, running SunOS 3 m68000-*-sunos3*
2716 Sun 2, running SunOS 4 m68000-*-sunos4*
2717 Motorola 680x0 running LynxOS m68*-*-lynxos*
2718 AT&T 3b1/Unix pc m68*-att-*
2719 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2720 decstation mips-dec-* mips-little-*
2721 riscos mips-*-riscos* mips-*-sysv*
2722 sonymips mips-sony-*
2723 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2725 * REMOVED configurations and files
2727 SGI Irix-4.x mips-sgi-irix4 or iris4
2728 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2729 Z8000 simulator z8k-zilog-none or z8ksim
2730 Matsushita MN10200 w/simulator mn10200-*-*
2731 H8/500 simulator h8500-hitachi-hms or h8500hms
2732 HP/PA running BSD hppa*-*-bsd*
2733 HP/PA running OSF/1 hppa*-*-osf*
2734 HP/PA Pro target hppa*-*-pro*
2735 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2736 386BSD i[3456]86-*-bsd*
2737 Sequent family i[3456]86-sequent-sysv4*
2738 i[3456]86-sequent-sysv*
2739 i[3456]86-sequent-bsd*
2740 SPARC running LynxOS sparc-*-lynxos*
2741 SPARC running SunOS 4 sparc-*-sunos4*
2742 Tsqware Sparclet sparclet-*-*
2743 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2745 *** Changes in GDB 6.0:
2749 Support for debugging the Objective-C programming language has been
2750 integrated into GDB.
2752 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2754 DWARF 2's Call Frame Information makes available compiler generated
2755 information that more exactly describes the program's run-time stack.
2756 By using this information, GDB is able to provide more robust stack
2759 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2760 have been updated to use a new backtrace mechanism which includes
2761 DWARF 2 CFI support.
2765 GDB's remote protocol has been extended to include support for hosted
2766 file I/O (where the remote target uses GDB's file system). See GDB's
2767 remote protocol documentation for details.
2769 * All targets using the new architecture framework.
2771 All of GDB's targets have been updated to use the new internal
2772 architecture framework. The way is now open for future GDB releases
2773 to include cross-architecture native debugging support (i386 on amd64,
2776 * GNU/Linux's Thread Local Storage (TLS)
2778 GDB now includes support for for the GNU/Linux implementation of
2779 per-thread variables.
2781 * GNU/Linux's Native POSIX Thread Library (NPTL)
2783 GDB's thread code has been updated to work with either the new
2784 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2786 * Separate debug info.
2788 GDB, in conjunction with BINUTILS, now supports a mechanism for
2789 automatically loading debug information from a separate file. Instead
2790 of shipping full debug and non-debug versions of system libraries,
2791 system integrators can now instead ship just the stripped libraries
2792 and optional debug files.
2794 * DWARF 2 Location Expressions
2796 DWARF 2 Location Expressions allow the compiler to more completely
2797 describe the location of variables (even in optimized code) to the
2800 GDB now includes preliminary support for location expressions (support
2801 for DW_OP_piece is still missing).
2805 A number of long standing bugs that caused GDB to die while starting a
2806 Java application have been fixed. GDB's Java support is now
2807 considered "useable".
2809 * GNU/Linux support for fork, vfork, and exec.
2811 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2812 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2815 * GDB supports logging output to a file
2817 There are two new commands, "set logging" and "show logging", which can be
2818 used to capture GDB's output to a file.
2820 * The meaning of "detach" has changed for gdbserver
2822 The "detach" command will now resume the application, as documented. To
2823 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2826 * d10v, m68hc11 `regs' command deprecated
2828 The `info registers' command has been updated so that it displays the
2829 registers using a format identical to the old `regs' command.
2833 A new command, "maint set profile on/off", has been added. This command can
2834 be used to enable or disable profiling while running GDB, to profile a
2835 session or a set of commands. In addition there is a new configure switch,
2836 "--enable-profiling", which will cause GDB to be compiled with profiling
2837 data, for more informative profiling results.
2839 * Default MI syntax changed to "mi2".
2841 The default MI (machine interface) syntax, enabled by the command line
2842 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2843 "mi1", can be enabled by specifying the option "-i=mi1".
2845 Support for the original "mi0" syntax (included in GDB 5.0) has been
2848 Fix for gdb/192: removed extraneous space when displaying frame level.
2849 Fix for gdb/672: update changelist is now output in mi list format.
2850 Fix for gdb/702: a -var-assign that updates the value now shows up
2851 in a subsequent -var-update.
2853 * New native configurations.
2855 FreeBSD/amd64 x86_64-*-freebsd*
2857 * Multi-arched targets.
2859 HP/PA HPUX11 hppa*-*-hpux*
2860 Renesas M32R/D w/simulator m32r-*-elf*
2862 * OBSOLETE configurations and files
2864 Configurations that have been declared obsolete in this release have
2865 been commented out. Unless there is activity to revive these
2866 configurations, the next release of GDB will have their sources
2867 permanently REMOVED.
2869 Z8000 simulator z8k-zilog-none or z8ksim
2870 Matsushita MN10200 w/simulator mn10200-*-*
2871 H8/500 simulator h8500-hitachi-hms or h8500hms
2872 HP/PA running BSD hppa*-*-bsd*
2873 HP/PA running OSF/1 hppa*-*-osf*
2874 HP/PA Pro target hppa*-*-pro*
2875 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2876 Sequent family i[3456]86-sequent-sysv4*
2877 i[3456]86-sequent-sysv*
2878 i[3456]86-sequent-bsd*
2879 Tsqware Sparclet sparclet-*-*
2880 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2882 * REMOVED configurations and files
2885 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2886 IBM AIX PS/2 i[3456]86-*-aix
2887 i386 running Mach 3.0 i[3456]86-*-mach3*
2888 i386 running Mach i[3456]86-*-mach*
2889 i386 running OSF/1 i[3456]86-*osf1mk*
2890 HP/Apollo 68k Family m68*-apollo*-sysv*,
2892 m68*-hp-bsd*, m68*-hp-hpux*
2893 Argonaut Risc Chip (ARC) arc-*-*
2894 Mitsubishi D30V d30v-*-*
2895 Fujitsu FR30 fr30-*-elf*
2896 OS/9000 i[34]86-*-os9k
2897 I960 with MON960 i960-*-coff
2899 * MIPS $fp behavior changed
2901 The convenience variable $fp, for the MIPS, now consistently returns
2902 the address of the current frame's base. Previously, depending on the
2903 context, $fp could refer to either $sp or the current frame's base
2904 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2905 The GNU Source-Level Debugger''.
2907 *** Changes in GDB 5.3:
2909 * GNU/Linux shared library multi-threaded performance improved.
2911 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2912 `/proc', in preference to `ptrace' for memory reads. This may result
2913 in an improvement in the start-up time of multi-threaded, shared
2914 library applications when run under GDB. One GDB user writes: ``loads
2915 shared libs like mad''.
2917 * ``gdbserver'' now supports multi-threaded applications on some targets
2919 Support for debugging multi-threaded applications which use
2920 the GNU/Linux LinuxThreads package has been added for
2921 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2922 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2924 * GDB now supports C/C++ preprocessor macros.
2926 GDB now expands preprocessor macro invocations in C/C++ expressions,
2927 and provides various commands for showing macro definitions and how
2930 The new command `macro expand EXPRESSION' expands any macro
2931 invocations in expression, and shows the result.
2933 The new command `show macro MACRO-NAME' shows the definition of the
2934 macro named MACRO-NAME, and where it was defined.
2936 Most compilers don't include information about macros in the debugging
2937 information by default. In GCC 3.1, for example, you need to compile
2938 your program with the options `-gdwarf-2 -g3'. If the macro
2939 information is present in the executable, GDB will read it.
2941 * Multi-arched targets.
2943 DEC Alpha (partial) alpha*-*-*
2944 DEC VAX (partial) vax-*-*
2946 National Semiconductor NS32000 (partial) ns32k-*-*
2947 Motorola 68000 (partial) m68k-*-*
2948 Motorola MCORE mcore-*-*
2952 Fujitsu FRV architecture added by Red Hat frv*-*-*
2955 * New native configurations
2957 Alpha NetBSD alpha*-*-netbsd*
2958 SH NetBSD sh*-*-netbsdelf*
2959 MIPS NetBSD mips*-*-netbsd*
2960 UltraSPARC NetBSD sparc64-*-netbsd*
2962 * OBSOLETE configurations and files
2964 Configurations that have been declared obsolete in this release have
2965 been commented out. Unless there is activity to revive these
2966 configurations, the next release of GDB will have their sources
2967 permanently REMOVED.
2969 Mitsubishi D30V d30v-*-*
2970 OS/9000 i[34]86-*-os9k
2971 IBM AIX PS/2 i[3456]86-*-aix
2972 Fujitsu FR30 fr30-*-elf*
2973 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2974 Argonaut Risc Chip (ARC) arc-*-*
2975 i386 running Mach 3.0 i[3456]86-*-mach3*
2976 i386 running Mach i[3456]86-*-mach*
2977 i386 running OSF/1 i[3456]86-*osf1mk*
2978 HP/Apollo 68k Family m68*-apollo*-sysv*,
2980 m68*-hp-bsd*, m68*-hp-hpux*
2981 I960 with MON960 i960-*-coff
2983 * OBSOLETE languages
2985 CHILL, a Pascal like language used by telecommunications companies.
2987 * REMOVED configurations and files
2989 AMD 29k family via UDI a29k-amd-udi, udi29k
2990 A29K VxWorks a29k-*-vxworks
2991 AMD 29000 embedded, using EBMON a29k-none-none
2992 AMD 29000 embedded with COFF a29k-none-coff
2993 AMD 29000 embedded with a.out a29k-none-aout
2995 testsuite/gdb.hp/gdb.threads-hp/ directory
2997 * New command "set max-user-call-depth <nnn>"
2999 This command allows the user to limit the call depth of user-defined
3000 commands. The default is 1024.
3002 * Changes in FreeBSD/i386 native debugging.
3004 Support for the "generate-core-file" has been added.
3006 * New commands "dump", "append", and "restore".
3008 These commands allow data to be copied from target memory
3009 to a bfd-format or binary file (dump and append), and back
3010 from a file into memory (restore).
3012 * Improved "next/step" support on multi-processor Alpha Tru64.
3014 The previous single-step mechanism could cause unpredictable problems,
3015 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3016 of a software single-step mechanism prevents this.
3018 *** Changes in GDB 5.2.1:
3026 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3027 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3028 Fix, by Joel Brobecker imported from mainline.
3030 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3031 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3032 Fix, by Fred Fish, imported from mainline.
3034 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3035 Surprisingly enough, it works now.
3036 By Michal Ludvig, imported from mainline.
3038 i386 hardware watchpoint support:
3039 avoid misses on second run for some targets.
3040 By Pierre Muller, imported from mainline.
3042 *** Changes in GDB 5.2:
3044 * New command "set trust-readonly-sections on[off]".
3046 This command is a hint that tells gdb that read-only sections
3047 really are read-only (ie. that their contents will not change).
3048 In this mode, gdb will go to the object file rather than the
3049 target to read memory from read-only sections (such as ".text").
3050 This can be a significant performance improvement on some
3051 (notably embedded) targets.
3053 * New command "generate-core-file" (or "gcore").
3055 This new gdb command allows the user to drop a core file of the child
3056 process state at any time. So far it's been implemented only for
3057 GNU/Linux and Solaris, but should be relatively easily ported to other
3058 hosts. Argument is core file name (defaults to core.<pid>).
3060 * New command line option
3062 GDB now accepts --pid or -p followed by a process id.
3064 * Change in command line behavior -- corefiles vs. process ids.
3066 There is a subtle behavior in the way in which GDB handles
3067 command line arguments. The first non-flag argument is always
3068 a program to debug, but the second non-flag argument may either
3069 be a corefile or a process id. Previously, GDB would attempt to
3070 open the second argument as a corefile, and if that failed, would
3071 issue a superfluous error message and then attempt to attach it as
3072 a process. Now, if the second argument begins with a non-digit,
3073 it will be treated as a corefile. If it begins with a digit,
3074 GDB will attempt to attach it as a process, and if no such process
3075 is found, will then attempt to open it as a corefile.
3077 * Changes in ARM configurations.
3079 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3080 configuration is fully multi-arch.
3082 * New native configurations
3084 ARM NetBSD arm*-*-netbsd*
3085 x86 OpenBSD i[3456]86-*-openbsd*
3086 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3087 Sparc64 running FreeBSD sparc64-*-freebsd*
3091 Sanyo XStormy16 xstormy16-elf
3093 * OBSOLETE configurations and files
3095 Configurations that have been declared obsolete in this release have
3096 been commented out. Unless there is activity to revive these
3097 configurations, the next release of GDB will have their sources
3098 permanently REMOVED.
3100 AMD 29k family via UDI a29k-amd-udi, udi29k
3101 A29K VxWorks a29k-*-vxworks
3102 AMD 29000 embedded, using EBMON a29k-none-none
3103 AMD 29000 embedded with COFF a29k-none-coff
3104 AMD 29000 embedded with a.out a29k-none-aout
3106 testsuite/gdb.hp/gdb.threads-hp/ directory
3108 * REMOVED configurations and files
3110 TI TMS320C80 tic80-*-*
3112 PowerPC Solaris powerpcle-*-solaris*
3113 PowerPC Windows NT powerpcle-*-cygwin32
3114 PowerPC Netware powerpc-*-netware*
3115 Harris/CXUX m88k m88*-harris-cxux*
3116 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3117 ns32k-utek-sysv* ns32k-utek-*
3118 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3119 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3120 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3121 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3122 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3124 * Changes to command line processing
3126 The new `--args' feature can be used to specify command-line arguments
3127 for the inferior from gdb's command line.
3129 * Changes to key bindings
3131 There is a new `operate-and-get-next' function bound to `C-o'.
3133 *** Changes in GDB 5.1.1
3135 Fix compile problem on DJGPP.
3137 Fix a problem with floating-point registers on the i386 being
3140 Fix to stop GDB crashing on .debug_str debug info.
3142 Numerous documentation fixes.
3144 Numerous testsuite fixes.
3146 *** Changes in GDB 5.1:
3148 * New native configurations
3150 Alpha FreeBSD alpha*-*-freebsd*
3151 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3152 MIPS GNU/Linux mips*-*-linux*
3153 MIPS SGI Irix 6.x mips*-sgi-irix6*
3154 ia64 AIX ia64-*-aix*
3155 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3159 Motorola 68HC11 and 68HC12 m68hc11-elf
3161 UltraSparc running GNU/Linux sparc64-*-linux*
3163 * OBSOLETE configurations and files
3165 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3166 Harris/CXUX m88k m88*-harris-cxux*
3167 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3168 ns32k-utek-sysv* ns32k-utek-*
3169 TI TMS320C80 tic80-*-*
3171 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3172 PowerPC Solaris powerpcle-*-solaris*
3173 PowerPC Windows NT powerpcle-*-cygwin32
3174 PowerPC Netware powerpc-*-netware*
3175 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3176 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3177 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3178 Apple Macintosh (MPW) host N/A
3180 stuff.c (Program to stuff files into a specially prepared space in kdb)
3181 kdb-start.c (Main loop for the standalone kernel debugger)
3183 Configurations that have been declared obsolete in this release have
3184 been commented out. Unless there is activity to revive these
3185 configurations, the next release of GDB will have their sources
3186 permanently REMOVED.
3188 * REMOVED configurations and files
3190 Altos 3068 m68*-altos-*
3191 Convex c1-*-*, c2-*-*
3193 ARM RISCix arm-*-* (as host)
3197 * GDB has been converted to ISO C.
3199 GDB's source code has been converted to ISO C. In particular, the
3200 sources are fully protoized, and rely on standard headers being
3205 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3207 * The MI enabled by default.
3209 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3210 revised and enabled by default. Packages which use GDB as a debugging
3211 engine behind a UI or another front end are encouraged to switch to
3212 using the GDB/MI interface, instead of the old annotations interface
3213 which is now deprecated.
3215 * Support for debugging Pascal programs.
3217 GDB now includes support for debugging Pascal programs. The following
3218 main features are supported:
3220 - Pascal-specific data types such as sets;
3222 - automatic recognition of Pascal sources based on file-name
3225 - Pascal-style display of data types, variables, and functions;
3227 - a Pascal expression parser.
3229 However, some important features are not yet supported.
3231 - Pascal string operations are not supported at all;
3233 - there are some problems with boolean types;
3235 - Pascal type hexadecimal constants are not supported
3236 because they conflict with the internal variables format;
3238 - support for Pascal objects and classes is not full yet;
3240 - unlike Pascal, GDB is case-sensitive for symbol names.
3242 * Changes in completion.
3244 Commands such as `shell', `run' and `set args', which pass arguments
3245 to inferior programs, now complete on file names, similar to what
3246 users expect at the shell prompt.
3248 Commands which accept locations, such as `disassemble', `print',
3249 `breakpoint', `until', etc. now complete on filenames as well as
3250 program symbols. Thus, if you type "break foob TAB", and the source
3251 files linked into the programs include `foobar.c', that file name will
3252 be one of the candidates for completion. However, file names are not
3253 considered for completion after you typed a colon that delimits a file
3254 name from a name of a function in that file, as in "break foo.c:bar".
3256 `set demangle-style' completes on available demangling styles.
3258 * New platform-independent commands:
3260 It is now possible to define a post-hook for a command as well as a
3261 hook that runs before the command. For more details, see the
3262 documentation of `hookpost' in the GDB manual.
3264 * Changes in GNU/Linux native debugging.
3266 Support for debugging multi-threaded programs has been completely
3267 revised for all platforms except m68k and sparc. You can now debug as
3268 many threads as your system allows you to have.
3270 Attach/detach is supported for multi-threaded programs.
3272 Support for SSE registers was added for x86. This doesn't work for
3273 multi-threaded programs though.
3275 * Changes in MIPS configurations.
3277 Multi-arch support is enabled for all MIPS configurations.
3279 GDB can now be built as native debugger on SGI Irix 6.x systems for
3280 debugging n32 executables. (Debugging 64-bit executables is not yet
3283 * Unified support for hardware watchpoints in all x86 configurations.
3285 Most (if not all) native x86 configurations support hardware-assisted
3286 breakpoints and watchpoints in a unified manner. This support
3287 implements debug register sharing between watchpoints, which allows to
3288 put a virtually infinite number of watchpoints on the same address,
3289 and also supports watching regions up to 16 bytes with several debug
3292 The new maintenance command `maintenance show-debug-regs' toggles
3293 debugging print-outs in functions that insert, remove, and test
3294 watchpoints and hardware breakpoints.
3296 * Changes in the DJGPP native configuration.
3298 New command ``info dos sysinfo'' displays assorted information about
3299 the CPU, OS, memory, and DPMI server.
3301 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3302 display information about segment descriptors stored in GDT, LDT, and
3305 New commands ``info dos pde'' and ``info dos pte'' display entries
3306 from Page Directory and Page Tables (for now works with CWSDPMI only).
3307 New command ``info dos address-pte'' displays the Page Table entry for
3308 a given linear address.
3310 GDB can now pass command lines longer than 126 characters to the
3311 program being debugged (requires an update to the libdbg.a library
3312 which is part of the DJGPP development kit).
3314 DWARF2 debug info is now supported.
3316 It is now possible to `step' and `next' through calls to `longjmp'.
3318 * Changes in documentation.
3320 All GDB documentation was converted to GFDL, the GNU Free
3321 Documentation License.
3323 Tracepoints-related commands are now fully documented in the GDB
3326 TUI, the Text-mode User Interface, is now documented in the manual.
3328 Tracepoints-related commands are now fully documented in the GDB
3331 The "GDB Internals" manual now has an index. It also includes
3332 documentation of `ui_out' functions, GDB coding standards, x86
3333 hardware watchpoints, and memory region attributes.
3335 * GDB's version number moved to ``version.in''
3337 The Makefile variable VERSION has been replaced by the file
3338 ``version.in''. People creating GDB distributions should update the
3339 contents of this file.
3343 GUD support is now a standard part of the EMACS distribution.
3345 *** Changes in GDB 5.0:
3347 * Improved support for debugging FP programs on x86 targets
3349 Unified and much-improved support for debugging floating-point
3350 programs on all x86 targets. In particular, ``info float'' now
3351 displays the FP registers in the same format on all x86 targets, with
3352 greater level of detail.
3354 * Improvements and bugfixes in hardware-assisted watchpoints
3356 It is now possible to watch array elements, struct members, and
3357 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3358 on x86 targets no longer erroneously trigger when the address is
3361 * Improvements in the native DJGPP version of GDB
3363 The distribution now includes all the scripts and auxiliary files
3364 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3365 machines ``out of the box''.
3367 The DJGPP version can now debug programs that use signals. It is
3368 possible to catch signals that happened in the debuggee, deliver
3369 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3370 would kill the program being debugged.) Programs that hook hardware
3371 interrupts (keyboard, timer, etc.) can also be debugged.
3373 It is now possible to debug DJGPP programs that redirect their
3374 standard handles or switch them to raw (as opposed to cooked) mode, or
3375 even close them. The command ``run < foo > bar'' works as expected,
3376 and ``info terminal'' reports useful information about the debuggee's
3377 terminal, including raw/cooked mode, redirection, etc.
3379 The DJGPP version now uses termios functions for console I/O, which
3380 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3383 DOS-style file names with drive letters are now fully supported by
3386 It is now possible to debug DJGPP programs that switch their working
3387 directory. It is also possible to rerun the debuggee any number of
3388 times without restarting GDB; thus, you can use the same setup,
3389 breakpoints, etc. for many debugging sessions.
3391 * New native configurations
3393 ARM GNU/Linux arm*-*-linux*
3394 PowerPC GNU/Linux powerpc-*-linux*
3398 Motorola MCore mcore-*-*
3399 x86 VxWorks i[3456]86-*-vxworks*
3400 PowerPC VxWorks powerpc-*-vxworks*
3401 TI TMS320C80 tic80-*-*
3403 * OBSOLETE configurations
3405 Altos 3068 m68*-altos-*
3406 Convex c1-*-*, c2-*-*
3408 ARM RISCix arm-*-* (as host)
3411 Configurations that have been declared obsolete will be commented out,
3412 but the code will be left in place. If there is no activity to revive
3413 these configurations before the next release of GDB, the sources will
3414 be permanently REMOVED.
3416 * Gould support removed
3418 Support for the Gould PowerNode and NP1 has been removed.
3420 * New features for SVR4
3422 On SVR4 native platforms (such as Solaris), if you attach to a process
3423 without first loading a symbol file, GDB will now attempt to locate and
3424 load symbols from the running process's executable file.
3426 * Many C++ enhancements
3428 C++ support has been greatly improved. Overload resolution now works properly
3429 in almost all cases. RTTI support is on the way.
3431 * Remote targets can connect to a sub-program
3433 A popen(3) style serial-device has been added. This device starts a
3434 sub-process (such as a stand-alone simulator) and then communicates
3435 with that. The sub-program to run is specified using the syntax
3436 ``|<program> <args>'' vis:
3438 (gdb) set remotedebug 1
3439 (gdb) target extended-remote |mn10300-elf-sim program-args
3441 * MIPS 64 remote protocol
3443 A long standing bug in the mips64 remote protocol where by GDB
3444 expected certain 32 bit registers (ex SR) to be transfered as 32
3445 instead of 64 bits has been fixed.
3447 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3448 added to provide backward compatibility with older versions of GDB.
3450 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3452 The command ``set remotebinarydownload'' command has been replaced by
3453 ``set remote X-packet''. Other commands in ``set remote'' family
3454 include ``set remote P-packet''.
3456 * Breakpoint commands accept ranges.
3458 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3459 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3460 ``tracepoint passcount'' also accepts a range of tracepoints.
3462 * ``apropos'' command added.
3464 The ``apropos'' command searches through command names and
3465 documentation strings, printing out matches, making it much easier to
3466 try to find a command that does what you are looking for.
3470 A new machine oriented interface (MI) has been added to GDB. This
3471 interface is designed for debug environments running GDB as a separate
3472 process. This is part of the long term libGDB project. See the
3473 "GDB/MI" chapter of the GDB manual for further information. It can be
3474 enabled by configuring with:
3476 .../configure --enable-gdbmi
3478 *** Changes in GDB-4.18:
3480 * New native configurations
3482 HP-UX 10.20 hppa*-*-hpux10.20
3483 HP-UX 11.x hppa*-*-hpux11.0*
3484 M68K GNU/Linux m68*-*-linux*
3488 Fujitsu FR30 fr30-*-elf*
3489 Intel StrongARM strongarm-*-*
3490 Mitsubishi D30V d30v-*-*
3492 * OBSOLETE configurations
3494 Gould PowerNode, NP1 np1-*-*, pn-*-*
3496 Configurations that have been declared obsolete will be commented out,
3497 but the code will be left in place. If there is no activity to revive
3498 these configurations before the next release of GDB, the sources will
3499 be permanently REMOVED.
3503 As a compatibility experiment, GDB's source files buildsym.h and
3504 buildsym.c have been converted to pure standard C, no longer
3505 containing any K&R compatibility code. We believe that all systems in
3506 use today either come with a standard C compiler, or have a GCC port
3507 available. If this is not true, please report the affected
3509 information about getting a standard C compiler if you don't have one
3514 GDB now uses readline 2.2.
3516 * set extension-language
3518 You can now control the mapping between filename extensions and source
3519 languages by using the `set extension-language' command. For instance,
3520 you can ask GDB to treat .c files as C++ by saying
3521 set extension-language .c c++
3522 The command `info extensions' lists all of the recognized extensions
3523 and their associated languages.
3525 * Setting processor type for PowerPC and RS/6000
3527 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3528 you can use the `set processor' command to specify what variant of the
3529 PowerPC family you are debugging. The command
3533 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3534 following PowerPC and RS6000 variants:
3536 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3537 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3539 403GC IBM PowerPC 403GC
3540 505 Motorola PowerPC 505
3541 860 Motorola PowerPC 860 or 850
3542 601 Motorola PowerPC 601
3543 602 Motorola PowerPC 602
3544 603 Motorola/IBM PowerPC 603 or 603e
3545 604 Motorola PowerPC 604 or 604e
3546 750 Motorola/IBM PowerPC 750 or 750
3548 At the moment, this command just tells GDB what to name the
3549 special-purpose processor registers. Since almost all the affected
3550 registers are inaccessible to user-level programs, this command is
3551 only useful for remote debugging in its present form.
3555 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3556 more extensive support for HP-UX. Added features include shared
3557 library support, kernel threads and hardware watchpoints for 11.00,
3558 support for HP's ANSI C and C++ compilers, and a compatibility mode
3559 for xdb and dbx commands.
3563 HP's donation includes the new concept of catchpoints, which is a
3564 generalization of the old catch command. On HP-UX, it is now possible
3565 to catch exec, fork, and vfork, as well as library loading.
3567 This means that the existing catch command has changed; its first
3568 argument now specifies the type of catch to be set up. See the
3569 output of "help catch" for a list of catchpoint types.
3571 * Debugging across forks
3573 On HP-UX, you can choose which process to debug when a fork() happens
3578 HP has donated a curses-based terminal user interface (TUI). To get
3579 it, build with --enable-tui. Although this can be enabled for any
3580 configuration, at present it only works for native HP debugging.
3582 * GDB remote protocol additions
3584 A new protocol packet 'X' that writes binary data is now available.
3585 Default behavior is to try 'X', then drop back to 'M' if the stub
3586 fails to respond. The settable variable `remotebinarydownload'
3587 allows explicit control over the use of 'X'.
3589 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3590 full 64-bit address. The command
3592 set remoteaddresssize 32
3594 can be used to revert to the old behaviour. For existing remote stubs
3595 the change should not be noticed, as the additional address information
3598 In order to assist in debugging stubs, you may use the maintenance
3599 command `packet' to send any text string to the stub. For instance,
3601 maint packet heythere
3603 sends the packet "$heythere#<checksum>". Note that it is very easy to
3604 disrupt a debugging session by sending the wrong packet at the wrong
3607 The compare-sections command allows you to compare section data on the
3608 target to what is in the executable file without uploading or
3609 downloading, by comparing CRC checksums.
3611 * Tracing can collect general expressions
3613 You may now collect general expressions at tracepoints. This requires
3614 further additions to the target-side stub; see tracepoint.c and
3615 doc/agentexpr.texi for further details.
3617 * mask-address variable for Mips
3619 For Mips targets, you may control the zeroing of the upper 32 bits of
3620 a 64-bit address by entering `set mask-address on'. This is mainly
3621 of interest to users of embedded R4xxx and R5xxx processors.
3623 * Higher serial baud rates
3625 GDB's serial code now allows you to specify baud rates 57600, 115200,
3626 230400, and 460800 baud. (Note that your host system may not be able
3627 to achieve all of these rates.)
3631 The i960 configuration now includes an initial implementation of a
3632 builtin simulator, contributed by Jim Wilson.
3635 *** Changes in GDB-4.17:
3637 * New native configurations
3639 Alpha GNU/Linux alpha*-*-linux*
3640 Unixware 2.x i[3456]86-unixware2*
3641 Irix 6.x mips*-sgi-irix6*
3642 PowerPC GNU/Linux powerpc-*-linux*
3643 PowerPC Solaris powerpcle-*-solaris*
3644 Sparc GNU/Linux sparc-*-linux*
3645 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3649 Argonaut Risc Chip (ARC) arc-*-*
3650 Hitachi H8/300S h8300*-*-*
3651 Matsushita MN10200 w/simulator mn10200-*-*
3652 Matsushita MN10300 w/simulator mn10300-*-*
3653 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3654 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3655 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3656 Mitsubishi D10V w/simulator d10v-*-*
3657 Mitsubishi M32R/D w/simulator m32r-*-elf*
3658 Tsqware Sparclet sparclet-*-*
3659 NEC V850 w/simulator v850-*-*
3661 * New debugging protocols
3663 ARM with RDI protocol arm*-*-*
3664 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3665 DDB and LSI variants of PMON protocol mips*-*-*
3666 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3667 PowerPC with SDS protocol powerpc{,le}-*-eabi
3668 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3672 All configurations can now understand and use the DWARF 2 debugging
3673 format. The choice is automatic, if the symbol file contains DWARF 2
3678 GDB now includes basic Java language support. This support is
3679 only useful with Java compilers that produce native machine code.
3681 * solib-absolute-prefix and solib-search-path
3683 For SunOS and SVR4 shared libraries, you may now set the prefix for
3684 loading absolute shared library symbol files, and the search path for
3685 locating non-absolute shared library symbol files.
3687 * Live range splitting
3689 GDB can now effectively debug code for which GCC has performed live
3690 range splitting as part of its optimization. See gdb/doc/LRS for
3691 more details on the expected format of the stabs information.
3695 GDB's support for the GNU Hurd, including thread debugging, has been
3696 updated to work with current versions of the Hurd.
3700 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3701 instruction set. ARM GDB automatically detects when Thumb
3702 instructions are in use, and adjusts disassembly and backtracing
3707 GDB's MIPS target configurations now handle the MIP16 16-bit
3712 GDB now includes support for overlays; if an executable has been
3713 linked such that multiple sections are based at the same address, GDB
3714 will decide which section to use for symbolic info. You can choose to
3715 control the decision manually, using overlay commands, or implement
3716 additional target-side support and use "overlay load-target" to bring
3717 in the overlay mapping. Do "help overlay" for more detail.
3721 The command "info symbol <address>" displays information about
3722 the symbol at the specified address.
3726 The standard remote protocol now includes an extension that allows
3727 asynchronous collection and display of trace data. This requires
3728 extensive support in the target-side debugging stub. Tracing mode
3729 includes a new interaction mode in GDB and new commands: see the
3730 file tracepoint.c for more details.
3734 Configurations for embedded MIPS now include a simulator contributed
3735 by Cygnus Solutions. The simulator supports the instruction sets
3736 of most MIPS variants.
3740 Sparc configurations may now include the ERC32 simulator contributed
3741 by the European Space Agency. The simulator is not built into
3742 Sparc targets by default; configure with --enable-sim to include it.
3746 For target configurations that may include multiple variants of a
3747 basic architecture (such as MIPS and SH), you may now set the
3748 architecture explicitly. "set arch" sets, "info arch" lists
3749 the possible architectures.
3751 *** Changes in GDB-4.16:
3753 * New native configurations
3755 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3756 M68K NetBSD m68k-*-netbsd*
3757 PowerPC AIX 4.x powerpc-*-aix*
3758 PowerPC MacOS powerpc-*-macos*
3759 PowerPC Windows NT powerpcle-*-cygwin32
3760 RS/6000 AIX 4.x rs6000-*-aix4*
3764 ARM with RDP protocol arm-*-*
3765 I960 with MON960 i960-*-coff
3766 MIPS VxWorks mips*-*-vxworks*
3767 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3768 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3770 Matra Sparclet sparclet-*-*
3774 The powerpc-eabi configuration now includes the PSIM simulator,
3775 contributed by Andrew Cagney, with assistance from Mike Meissner.
3776 PSIM is a very elaborate model of the PowerPC, including not only
3777 basic instruction set execution, but also details of execution unit
3778 performance and I/O hardware. See sim/ppc/README for more details.
3782 GDB now works with Solaris 2.5.
3784 * Windows 95/NT native
3786 GDB will now work as a native debugger on Windows 95 and Windows NT.
3787 To build it from source, you must use the "gnu-win32" environment,
3788 which uses a DLL to emulate enough of Unix to run the GNU tools.
3789 Further information, binaries, and sources are available at
3790 ftp.cygnus.com, under pub/gnu-win32.
3792 * dont-repeat command
3794 If a user-defined command includes the command `dont-repeat', then the
3795 command will not be repeated if the user just types return. This is
3796 useful if the command is time-consuming to run, so that accidental
3797 extra keystrokes don't run the same command many times.
3799 * Send break instead of ^C
3801 The standard remote protocol now includes an option to send a break
3802 rather than a ^C to the target in order to interrupt it. By default,
3803 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3805 * Remote protocol timeout
3807 The standard remote protocol includes a new variable `remotetimeout'
3808 that allows you to set the number of seconds before GDB gives up trying
3809 to read from the target. The default value is 2.
3811 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3813 By default GDB will automatically keep track of objects as they are
3814 loaded and unloaded by the dynamic linker. By using the command `set
3815 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3816 when shared library events occur, thus allowing you to set breakpoints
3817 in shared libraries which are explicitly loaded by the inferior.
3819 Note this feature does not work on hpux8. On hpux9 you must link
3820 /usr/lib/end.o into your program. This feature should work
3821 automatically on hpux10.
3823 * Irix 5.x hardware watchpoint support
3825 Irix 5 configurations now support the use of hardware watchpoints.
3827 * Mips protocol "SYN garbage limit"
3829 When debugging a Mips target using the `target mips' protocol, you
3830 may set the number of characters that GDB will ignore by setting
3831 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3832 every character. The default value is 1050.
3834 * Recording and replaying remote debug sessions
3836 If you set `remotelogfile' to the name of a file, gdb will write to it
3837 a recording of a remote debug session. This recording may then be
3838 replayed back to gdb using "gdbreplay". See gdbserver/README for
3839 details. This is useful when you have a problem with GDB while doing
3840 remote debugging; you can make a recording of the session and send it
3841 to someone else, who can then recreate the problem.
3843 * Speedups for remote debugging
3845 GDB includes speedups for downloading and stepping MIPS systems using
3846 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3847 and more efficient S-record downloading.
3849 * Memory use reductions and statistics collection
3851 GDB now uses less memory and reports statistics about memory usage.
3852 Try the `maint print statistics' command, for example.
3854 *** Changes in GDB-4.15:
3856 * Psymtabs for XCOFF
3858 The symbol reader for AIX GDB now uses partial symbol tables. This
3859 can greatly improve startup time, especially for large executables.
3861 * Remote targets use caching
3863 Remote targets now use a data cache to speed up communication with the
3864 remote side. The data cache could lead to incorrect results because
3865 it doesn't know about volatile variables, thus making it impossible to
3866 debug targets which use memory mapped I/O devices. `set remotecache
3867 off' turns the the data cache off.
3869 * Remote targets may have threads
3871 The standard remote protocol now includes support for multiple threads
3872 in the target system, using new protocol commands 'H' and 'T'. See
3873 gdb/remote.c for details.
3877 If GDB is configured with `--enable-netrom', then it will include
3878 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3879 acts as though it is a bank of ROM on the target board, but you can
3880 write into it over the network. GDB's support consists only of
3881 support for fast loading into the emulated ROM; to debug, you must use
3882 another protocol, such as standard remote protocol. The usual
3883 sequence is something like
3885 target nrom <netrom-hostname>
3887 target remote <netrom-hostname>:1235
3891 GDB now includes support for the Apple Macintosh, as a host only. It
3892 may be run as either an MPW tool or as a standalone application, and
3893 it can debug through the serial port. All the usual GDB commands are
3894 available, but to the target command, you must supply "serial" as the
3895 device type instead of "/dev/ttyXX". See mpw-README in the main
3896 directory for more information on how to build. The MPW configuration
3897 scripts */mpw-config.in support only a few targets, and only the
3898 mips-idt-ecoff target has been tested.
3902 GDB configuration now uses autoconf. This is not user-visible,
3903 but does simplify configuration and building.
3907 GDB now supports hpux10.
3909 *** Changes in GDB-4.14:
3911 * New native configurations
3913 x86 FreeBSD i[345]86-*-freebsd
3914 x86 NetBSD i[345]86-*-netbsd
3915 NS32k NetBSD ns32k-*-netbsd
3916 Sparc NetBSD sparc-*-netbsd
3920 A29K VxWorks a29k-*-vxworks
3921 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3922 CPU32 EST-300 emulator m68*-*-est*
3923 PowerPC ELF powerpc-*-elf
3926 * Alpha OSF/1 support for procfs
3928 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3929 possible to attach to running processes. As the mounting of the /proc
3930 filesystem is optional on the Alpha, GDB automatically determines
3931 the availability of /proc during startup. This can lead to problems
3932 if /proc is unmounted after GDB has been started.
3934 * Arguments to user-defined commands
3936 User commands may accept up to 10 arguments separated by whitespace.
3937 Arguments are accessed within the user command via $arg0..$arg9. A
3940 print $arg0 + $arg1 + $arg2
3942 To execute the command use:
3945 Defines the command "adder" which prints the sum of its three arguments.
3946 Note the arguments are text substitutions, so they may reference variables,
3947 use complex expressions, or even perform inferior function calls.
3949 * New `if' and `while' commands
3951 This makes it possible to write more sophisticated user-defined
3952 commands. Both commands take a single argument, which is the
3953 expression to evaluate, and must be followed by the commands to
3954 execute, one per line, if the expression is nonzero, the list being
3955 terminated by the word `end'. The `if' command list may include an
3956 `else' word, which causes the following commands to be executed only
3957 if the expression is zero.
3959 * Fortran source language mode
3961 GDB now includes partial support for Fortran 77. It will recognize
3962 Fortran programs and can evaluate a subset of Fortran expressions, but
3963 variables and functions may not be handled correctly. GDB will work
3964 with G77, but does not yet know much about symbols emitted by other
3967 * Better HPUX support
3969 Most debugging facilities now work on dynamic executables for HPPAs
3970 running hpux9 or later. You can attach to running dynamically linked
3971 processes, but by default the dynamic libraries will be read-only, so
3972 for instance you won't be able to put breakpoints in them. To change
3973 that behavior do the following before running the program:
3979 This will cause the libraries to be mapped private and read-write.
3980 To revert to the normal behavior, do this:
3986 You cannot set breakpoints or examine data in the library until after
3987 the library is loaded if the function/data symbols do not have
3990 GDB can now also read debug symbols produced by the HP C compiler on
3991 HPPAs (sorry, no C++, Fortran or 68k support).
3993 * Target byte order now dynamically selectable
3995 You can choose which byte order to use with a target system, via the
3996 commands "set endian big" and "set endian little", and you can see the
3997 current setting by using "show endian". You can also give the command
3998 "set endian auto", in which case GDB will use the byte order
3999 associated with the executable. Currently, only embedded MIPS
4000 configurations support dynamic selection of target byte order.
4002 * New DOS host serial code
4004 This version uses DPMI interrupts to handle buffered I/O, so you
4005 no longer need to run asynctsr when debugging boards connected to
4008 *** Changes in GDB-4.13:
4010 * New "complete" command
4012 This lists all the possible completions for the rest of the line, if it
4013 were to be given as a command itself. This is intended for use by emacs.
4015 * Trailing space optional in prompt
4017 "set prompt" no longer adds a space for you after the prompt you set. This
4018 allows you to set a prompt which ends in a space or one that does not.
4020 * Breakpoint hit counts
4022 "info break" now displays a count of the number of times the breakpoint
4023 has been hit. This is especially useful in conjunction with "ignore"; you
4024 can ignore a large number of breakpoint hits, look at the breakpoint info
4025 to see how many times the breakpoint was hit, then run again, ignoring one
4026 less than that number, and this will get you quickly to the last hit of
4029 * Ability to stop printing at NULL character
4031 "set print null-stop" will cause GDB to stop printing the characters of
4032 an array when the first NULL is encountered. This is useful when large
4033 arrays actually contain only short strings.
4035 * Shared library breakpoints
4037 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4038 breakpoints in shared libraries before the executable is run.
4040 * Hardware watchpoints
4042 There is a new hardware breakpoint for the watch command for sparclite
4043 targets. See gdb/sparclite/hw_breakpoint.note.
4045 Hardware watchpoints are also now supported under GNU/Linux.
4049 Annotations have been added. These are for use with graphical interfaces,
4050 and are still experimental. Currently only gdba.el uses these.
4052 * Improved Irix 5 support
4054 GDB now works properly with Irix 5.2.
4056 * Improved HPPA support
4058 GDB now works properly with the latest GCC and GAS.
4060 * New native configurations
4062 Sequent PTX4 i[34]86-sequent-ptx4
4063 HPPA running OSF/1 hppa*-*-osf*
4064 Atari TT running SVR4 m68*-*-sysv4*
4065 RS/6000 LynxOS rs6000-*-lynxos*
4069 OS/9000 i[34]86-*-os9k
4070 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4073 * Hitachi SH7000 and E7000-PC ICE support
4075 There is now support for communicating with the Hitachi E7000-PC ICE.
4076 This is available automatically when GDB is configured for the SH.
4080 As usual, a variety of small fixes and improvements, both generic
4081 and configuration-specific. See the ChangeLog for more detail.
4083 *** Changes in GDB-4.12:
4085 * Irix 5 is now supported
4089 GDB-4.12 on the HPPA has a number of changes which make it unable
4090 to debug the output from the currently released versions of GCC and
4091 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4092 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4093 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4096 *** Changes in GDB-4.11:
4098 * User visible changes:
4102 The "set remotedebug" option is now consistent between the mips remote
4103 target, remote targets using the gdb-specific protocol, UDI (AMD's
4104 debug protocol for the 29k) and the 88k bug monitor. It is now an
4105 integer specifying a debug level (normally 0 or 1, but 2 means more
4106 debugging info for the mips target).
4108 * DEC Alpha native support
4110 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4111 debug info, but GDB works fairly well with the DEC compiler and should
4112 work with a future GCC release. See the README file for a few
4113 Alpha-specific notes.
4115 * Preliminary thread implementation
4117 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4119 * LynxOS native and target support for 386
4121 This release has been hosted on LynxOS 2.2, and also can be configured
4122 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4125 * Improvements in C++ mangling/demangling.
4127 This release has much better g++ debugging, specifically in name
4128 mangling/demangling, virtual function calls, print virtual table,
4129 call methods, ...etc.
4131 *** Changes in GDB-4.10:
4133 * User visible changes:
4135 Remote debugging using the GDB-specific (`target remote') protocol now
4136 supports the `load' command. This is only useful if you have some
4137 other way of getting the stub to the target system, and you can put it
4138 somewhere in memory where it won't get clobbered by the download.
4140 Filename completion now works.
4142 When run under emacs mode, the "info line" command now causes the
4143 arrow to point to the line specified. Also, "info line" prints
4144 addresses in symbolic form (as well as hex).
4146 All vxworks based targets now support a user settable option, called
4147 vxworks-timeout. This option represents the number of seconds gdb
4148 should wait for responses to rpc's. You might want to use this if
4149 your vxworks target is, perhaps, a slow software simulator or happens
4150 to be on the far side of a thin network line.
4154 This release contains support for using a DEC alpha as a GDB host for
4155 cross debugging. Native alpha debugging is not supported yet.
4158 *** Changes in GDB-4.9:
4162 This is the first GDB release which is accompanied by a matching testsuite.
4163 The testsuite requires installation of dejagnu, which should be available
4164 via ftp from most sites that carry GNU software.
4168 'Cfront' style demangling has had its name changed to 'ARM' style, to
4169 emphasize that it was written from the specifications in the C++ Annotated
4170 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4171 disclaimers, it still generated too much confusion with users attempting to
4172 use gdb with AT&T cfront.
4176 GDB now uses a standard remote interface to a simulator library.
4177 So far, the library contains simulators for the Zilog Z8001/2, the
4178 Hitachi H8/300, H8/500 and Super-H.
4180 * New targets supported
4182 H8/300 simulator h8300-hitachi-hms or h8300hms
4183 H8/500 simulator h8500-hitachi-hms or h8500hms
4184 SH simulator sh-hitachi-hms or sh
4185 Z8000 simulator z8k-zilog-none or z8ksim
4186 IDT MIPS board over serial line mips-idt-ecoff
4188 Cross-debugging to GO32 targets is supported. It requires a custom
4189 version of the i386-stub.c module which is integrated with the
4190 GO32 memory extender.
4192 * New remote protocols
4194 MIPS remote debugging protocol.
4196 * New source languages supported
4198 This version includes preliminary support for Chill, a Pascal like language
4199 used by telecommunications companies. Chill support is also being integrated
4200 into the GNU compiler, but we don't know when it will be publically available.
4203 *** Changes in GDB-4.8:
4205 * HP Precision Architecture supported
4207 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4208 version of this support was available as a set of patches from the
4209 University of Utah. GDB does not support debugging of programs
4210 compiled with the HP compiler, because HP will not document their file
4211 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4212 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4214 Many problems in the preliminary version have been fixed.
4216 * Faster and better demangling
4218 We have improved template demangling and fixed numerous bugs in the GNU style
4219 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4220 character types (wchar_t) are now supported. Demangling of each symbol is now
4221 only done once, and is cached when the symbol table for a file is read in.
4222 This results in a small increase in memory usage for C programs, a moderate
4223 increase in memory usage for C++ programs, and a fantastic speedup in
4226 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4227 from the specifications in the Annotated Reference Manual, which AT&T's
4228 compiler does not actually implement.
4230 * G++ multiple inheritance compiler problem
4232 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4233 inheritance lattices was reworked to properly discover ambiguities. We
4234 recently found an example which causes this new algorithm to fail in a
4235 very subtle way, producing bad debug information for those classes.
4236 The file 'gcc.patch' (in this directory) can be applied to gcc to
4237 circumvent the problem. A future GCC release will contain a complete
4240 The previous G++ debug info problem (mentioned below for the gdb-4.7
4241 release) is fixed in gcc version 2.3.2.
4243 * Improved configure script
4245 The `configure' script will now attempt to guess your system type if
4246 you don't supply a host system type. The old scheme of supplying a
4247 host system triplet is preferable over using this. All the magic is
4248 done in the new `config.guess' script. Examine it for details.
4250 We have also brought our configure script much more in line with the FSF's
4251 version. It now supports the --with-xxx options. In particular,
4252 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4253 The resulting GDB will not be able to read arbitrary object file formats --
4254 only the format ``expected'' to be used on the configured target system.
4255 We hope to make this the default in a future release.
4257 * Documentation improvements
4259 There's new internal documentation on how to modify GDB, and how to
4260 produce clean changes to the code. We implore people to read it
4261 before submitting changes.
4263 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4264 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4265 `info' files are also provided. To build `info' files from scratch,
4266 you will need the latest `makeinfo' release, which will be available in
4267 a future texinfo-X.Y release.
4269 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4270 We're not sure exactly which versions have this problem, but it has
4271 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4272 or better. If that isn't possible, there is a patch in
4273 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4274 around this problem.
4278 GDB now supports array constants that can be used in expressions typed in by
4279 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4280 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4283 The new directory `gdb/sparclite' contains a program that demonstrates
4284 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4286 * New native hosts supported
4288 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4289 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4291 * New targets supported
4293 AMD 29k family via UDI a29k-amd-udi or udi29k
4295 * New file formats supported
4297 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4298 HPUX core files, and SCO 3.2v2 core files.
4302 Attaching to processes now works again; thanks for the many bug reports.
4304 We have also stomped on a bunch of core dumps caused by
4305 printf_filtered("%s") problems.
4307 We eliminated a copyright problem on the rpc and ptrace header files
4308 for VxWorks, which was discovered at the last minute during the 4.7
4309 release. You should now be able to build a VxWorks GDB.
4311 You can now interrupt gdb while an attached process is running. This
4312 will cause the attached process to stop, and give control back to GDB.
4314 We fixed problems caused by using too many file descriptors
4315 for reading symbols from object files and libraries. This was
4316 especially a problem for programs that used many (~100) shared
4319 The `step' command now only enters a subroutine if there is line number
4320 information for the subroutine. Otherwise it acts like the `next'
4321 command. Previously, `step' would enter subroutines if there was
4322 any debugging information about the routine. This avoids problems
4323 when using `cc -g1' on MIPS machines.
4325 * Internal improvements
4327 GDB's internal interfaces have been improved to make it easier to support
4328 debugging of multiple languages in the future.
4330 GDB now uses a common structure for symbol information internally.
4331 Minimal symbols (derived from linkage symbols in object files), partial
4332 symbols (from a quick scan of debug information), and full symbols
4333 contain a common subset of information, making it easier to write
4334 shared code that handles any of them.
4336 * New command line options
4338 We now accept --silent as an alias for --quiet.
4342 The memory-mapped-malloc library is now licensed under the GNU Library
4343 General Public License.
4345 *** Changes in GDB-4.7:
4347 * Host/native/target split
4349 GDB has had some major internal surgery to untangle the support for
4350 hosts and remote targets. Now, when you configure GDB for a remote
4351 target, it will no longer load in all of the support for debugging
4352 local programs on the host. When fully completed and tested, this will
4353 ensure that arbitrary host/target combinations are possible.
4355 The primary conceptual shift is to separate the non-portable code in
4356 GDB into three categories. Host specific code is required any time GDB
4357 is compiled on that host, regardless of the target. Target specific
4358 code relates to the peculiarities of the target, but can be compiled on
4359 any host. Native specific code is everything else: it can only be
4360 built when the host and target are the same system. Child process
4361 handling and core file support are two common `native' examples.
4363 GDB's use of /proc for controlling Unix child processes is now cleaner.
4364 It has been split out into a single module under the `target_ops' vector,
4365 plus two native-dependent functions for each system that uses /proc.
4367 * New hosts supported
4369 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4370 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4371 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4373 * New targets supported
4375 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4376 68030 and CPU32 m68030-*-*, m68332-*-*
4378 * New native hosts supported
4380 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4381 (386bsd is not well tested yet)
4382 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4384 * New file formats supported
4386 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4387 supports reading of `a.out.adobe' object files, which are an a.out
4388 format extended with minimal information about multiple sections.
4392 `show copying' is the same as the old `info copying'.
4393 `show warranty' is the same as `info warrantee'.
4394 These were renamed for consistency. The old commands continue to work.
4396 `info handle' is a new alias for `info signals'.
4398 You can now define pre-command hooks, which attach arbitrary command
4399 scripts to any command. The commands in the hook will be executed
4400 prior to the user's command. You can also create a hook which will be
4401 executed whenever the program stops. See gdb.texinfo.
4405 We now deal with Cfront style name mangling, and can even extract type
4406 info from mangled symbols. GDB can automatically figure out which
4407 symbol mangling style your C++ compiler uses.
4409 Calling of methods and virtual functions has been improved as well.
4413 The crash that occured when debugging Sun Ansi-C compiled binaries is
4414 fixed. This was due to mishandling of the extra N_SO stabs output
4417 We also finally got Ultrix 4.2 running in house, and fixed core file
4418 support, with help from a dozen people on the net.
4420 John M. Farrell discovered that the reason that single-stepping was so
4421 slow on all of the Mips based platforms (primarily SGI and DEC) was
4422 that we were trying to demangle and lookup a symbol used for internal
4423 purposes on every instruction that was being stepped through. Changing
4424 the name of that symbol so that it couldn't be mistaken for a C++
4425 mangled symbol sped things up a great deal.
4427 Rich Pixley sped up symbol lookups in general by getting much smarter
4428 about when C++ symbol mangling is necessary. This should make symbol
4429 completion (TAB on the command line) much faster. It's not as fast as
4430 we'd like, but it's significantly faster than gdb-4.6.
4434 A new user controllable variable 'call_scratch_address' can
4435 specify the location of a scratch area to be used when GDB
4436 calls a function in the target. This is necessary because the
4437 usual method of putting the scratch area on the stack does not work
4438 in systems that have separate instruction and data spaces.
4440 We integrated changes to support the 29k UDI (Universal Debugger
4441 Interface), but discovered at the last minute that we didn't have all
4442 of the appropriate copyright paperwork. We are working with AMD to
4443 resolve this, and hope to have it available soon.
4447 We have sped up the remote serial line protocol, especially for targets
4448 with lots of registers. It now supports a new `expedited status' ('T')
4449 message which can be used in place of the existing 'S' status message.
4450 This allows the remote stub to send only the registers that GDB
4451 needs to make a quick decision about single-stepping or conditional
4452 breakpoints, eliminating the need to fetch the entire register set for
4453 each instruction being stepped through.
4455 The GDB remote serial protocol now implements a write-through cache for
4456 registers, only re-reading the registers if the target has run.
4458 There is also a new remote serial stub for SPARC processors. You can
4459 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4460 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4461 processor with a serial port.
4465 Configure.in files have become much easier to read and modify. A new
4466 `table driven' format makes it more obvious what configurations are
4467 supported, and what files each one uses.
4471 There is a new opcodes library which will eventually contain all of the
4472 disassembly routines and opcode tables. At present, it only contains
4473 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4474 disassembler (binutils/objdump) to share these routines.
4476 The libiberty library is now copylefted under the GNU Library General
4477 Public License. This allows more liberal use, and was done so libg++
4478 can use it. This makes no difference to GDB, since the Library License
4479 grants all the rights from the General Public License.
4483 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4484 reference to the stabs symbol info used by the debugger. It is (as far
4485 as we know) the only published document on this fascinating topic. We
4486 encourage you to read it, compare it to the stabs information on your
4487 system, and send improvements on the document in general (to
4490 And, of course, many bugs have been fixed.
4493 *** Changes in GDB-4.6:
4495 * Better support for C++ function names
4497 GDB now accepts as input the "demangled form" of C++ overloaded function
4498 names and member function names, and can do command completion on such names
4499 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4500 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4501 Make use of command completion, it is your friend.
4503 GDB also now accepts a variety of C++ mangled symbol formats. They are
4504 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4505 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4506 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4507 for the list of formats.
4509 * G++ symbol mangling problem
4511 Recent versions of gcc have a bug in how they emit debugging information for
4512 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4513 directory) can be applied to gcc to fix the problem. Alternatively, if you
4514 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4515 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4516 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4519 * New 'maintenance' command
4521 All of the commands related to hacking GDB internals have been moved out of
4522 the main command set, and now live behind the 'maintenance' command. This
4523 can also be abbreviated as 'mt'. The following changes were made:
4525 dump-me -> maintenance dump-me
4526 info all-breakpoints -> maintenance info breakpoints
4527 printmsyms -> maintenance print msyms
4528 printobjfiles -> maintenance print objfiles
4529 printpsyms -> maintenance print psymbols
4530 printsyms -> maintenance print symbols
4532 The following commands are new:
4534 maintenance demangle Call internal GDB demangler routine to
4535 demangle a C++ link name and prints the result.
4536 maintenance print type Print a type chain for a given symbol
4538 * Change to .gdbinit file processing
4540 We now read the $HOME/.gdbinit file before processing the argv arguments
4541 (e.g. reading symbol files or core files). This allows global parameters to
4542 be set, which will apply during the symbol reading. The ./.gdbinit is still
4543 read after argv processing.
4545 * New hosts supported
4547 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4549 GNU/Linux support i386-unknown-linux or linux
4551 We are also including code to support the HP/PA running BSD and HPUX. This
4552 is almost guaranteed not to work, as we didn't have time to test or build it
4553 for this release. We are including it so that the more adventurous (or
4554 masochistic) of you can play with it. We also had major problems with the
4555 fact that the compiler that we got from HP doesn't support the -g option.
4558 * New targets supported
4560 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4562 * More smarts about finding #include files
4564 GDB now remembers the compilation directory for all include files, and for
4565 all files from which C is generated (like yacc and lex sources). This
4566 greatly improves GDB's ability to find yacc/lex sources, and include files,
4567 especially if you are debugging your program from a directory different from
4568 the one that contains your sources.
4570 We also fixed a bug which caused difficulty with listing and setting
4571 breakpoints in include files which contain C code. (In the past, you had to
4572 try twice in order to list an include file that you hadn't looked at before.)
4574 * Interesting infernals change
4576 GDB now deals with arbitrary numbers of sections, where the symbols for each
4577 section must be relocated relative to that section's landing place in the
4578 target's address space. This work was needed to support ELF with embedded
4579 stabs used by Solaris-2.0.
4581 * Bug fixes (of course!)
4583 There have been loads of fixes for the following things:
4584 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4585 i960, stabs, DOS(GO32), procfs, etc...
4587 See the ChangeLog for details.
4589 *** Changes in GDB-4.5:
4591 * New machines supported (host and target)
4593 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4595 SGI Irix-4.x mips-sgi-irix4 or iris4
4597 * New malloc package
4599 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4600 Mmalloc is capable of handling mutiple heaps of memory. It is also
4601 capable of saving a heap to a file, and then mapping it back in later.
4602 This can be used to greatly speedup the startup of GDB by using a
4603 pre-parsed symbol table which lives in a mmalloc managed heap. For
4604 more details, please read mmalloc/mmalloc.texi.
4608 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4609 'help info proc' for details.
4611 * MIPS ecoff symbol table format
4613 The code that reads MIPS symbol table format is now supported on all hosts.
4614 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4617 * File name changes for MS-DOS
4619 Many files in the config directories have been renamed to make it easier to
4620 support GDB on MS-DOSe systems (which have very restrictive file name
4621 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4622 environment) is close to working but has some remaining problems. Note
4623 that debugging of DOS programs is not supported, due to limitations
4624 in the ``operating system'', but it can be used to host cross-debugging.
4626 * Cross byte order fixes
4628 Many fixes have been made to support cross debugging of Sparc and MIPS
4629 targets from hosts whose byte order differs.
4631 * New -mapped and -readnow options
4633 If memory-mapped files are available on your system through the 'mmap'
4634 system call, you can use the -mapped option on the `file' or
4635 `symbol-file' commands to cause GDB to write the symbols from your
4636 program into a reusable file. If the program you are debugging is
4637 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4638 Future GDB debugging sessions will notice the presence of this file,
4639 and will quickly map in symbol information from it, rather than reading
4640 the symbol table from the executable program. Using the '-mapped'
4641 option in a GDB `file' or `symbol-file' command has the same effect as
4642 starting GDB with the '-mapped' command-line option.
4644 You can cause GDB to read the entire symbol table immediately by using
4645 the '-readnow' option with any of the commands that load symbol table
4646 information (or on the GDB command line). This makes the command
4647 slower, but makes future operations faster.
4649 The -mapped and -readnow options are typically combined in order to
4650 build a `fred.syms' file that contains complete symbol information.
4651 A simple GDB invocation to do nothing but build a `.syms' file for future
4654 gdb -batch -nx -mapped -readnow programname
4656 The `.syms' file is specific to the host machine on which GDB is run.
4657 It holds an exact image of GDB's internal symbol table. It cannot be
4658 shared across multiple host platforms.
4660 * longjmp() handling
4662 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4663 siglongjmp() without losing control. This feature has not yet been ported to
4664 all systems. It currently works on many 386 platforms, all MIPS-based
4665 platforms (SGI, DECstation, etc), and Sun3/4.
4669 Preliminary work has been put in to support the new Solaris OS from Sun. At
4670 this time, it can control and debug processes, but it is not capable of
4675 As always, many many bug fixes. The major areas were with g++, and mipsread.
4676 People using the MIPS-based platforms should experience fewer mysterious
4677 crashes and trashed symbol tables.
4679 *** Changes in GDB-4.4:
4681 * New machines supported (host and target)
4683 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4685 BSD Reno on Vax vax-dec-bsd
4686 Ultrix on Vax vax-dec-ultrix
4688 * New machines supported (target)
4690 AMD 29000 embedded, using EBMON a29k-none-none
4694 GDB continues to improve its handling of C++. `References' work better.
4695 The demangler has also been improved, and now deals with symbols mangled as
4696 per the Annotated C++ Reference Guide.
4698 GDB also now handles `stabs' symbol information embedded in MIPS
4699 `ecoff' symbol tables. Since the ecoff format was not easily
4700 extensible to handle new languages such as C++, this appeared to be a
4701 good way to put C++ debugging info into MIPS binaries. This option
4702 will be supported in the GNU C compiler, version 2, when it is
4705 * New features for SVR4
4707 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4708 shared libraries. Debugging dynamically linked programs should present
4709 only minor differences from debugging statically linked programs.
4711 The `info proc' command will print out information about any process
4712 on an SVR4 system (including the one you are debugging). At the moment,
4713 it prints the address mappings of the process.
4715 If you bring up GDB on another SVR4 system, please send mail to
4718 * Better dynamic linking support in SunOS
4720 Reading symbols from shared libraries which contain debugging symbols
4721 now works properly. However, there remain issues such as automatic
4722 skipping of `transfer vector' code during function calls, which
4723 make it harder to debug code in a shared library, than to debug the
4724 same code linked statically.
4728 GDB is now using the latest `getopt' routines from the FSF. This
4729 version accepts the -- prefix for options with long names. GDB will
4730 continue to accept the old forms (-option and +option) as well.
4731 Various single letter abbreviations for options have been explicity
4732 added to the option table so that they won't get overshadowed in the
4733 future by other options that begin with the same letter.
4737 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4738 Many assorted bugs have been handled. Many more remain to be handled.
4739 See the various ChangeLog files (primarily in gdb and bfd) for details.
4742 *** Changes in GDB-4.3:
4744 * New machines supported (host and target)
4746 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4747 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4748 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4750 * Almost SCO Unix support
4752 We had hoped to support:
4753 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4754 (except for core file support), but we discovered very late in the release
4755 that it has problems with process groups that render gdb unusable. Sorry
4756 about that. I encourage people to fix it and post the fixes.
4758 * Preliminary ELF and DWARF support
4760 GDB can read ELF object files on System V Release 4, and can handle
4761 debugging records for C, in DWARF format, in ELF files. This support
4762 is preliminary. If you bring up GDB on another SVR4 system, please
4768 GDB now uses the latest `readline' library. One user-visible change
4769 is that two tabs will list possible command completions, which previously
4770 required typing M-? (meta-question mark, or ESC ?).
4774 The `stepi' bug that many of you noticed has been squashed.
4775 Many bugs in C++ have been handled. Many more remain to be handled.
4776 See the various ChangeLog files (primarily in gdb and bfd) for details.
4778 * State of the MIPS world (in case you wondered):
4780 GDB can understand the symbol tables emitted by the compilers
4781 supplied by most vendors of MIPS-based machines, including DEC. These
4782 symbol tables are in a format that essentially nobody else uses.
4784 Some versions of gcc come with an assembler post-processor called
4785 mips-tfile. This program is required if you want to do source-level
4786 debugging of gcc-compiled programs. I believe FSF does not ship
4787 mips-tfile with gcc version 1, but it will eventually come with gcc
4790 Debugging of g++ output remains a problem. g++ version 1.xx does not
4791 really support it at all. (If you're lucky, you should be able to get
4792 line numbers and stack traces to work, but no parameters or local
4793 variables.) With some work it should be possible to improve the
4796 When gcc version 2 is released, you will have somewhat better luck.
4797 However, even then you will get confusing results for inheritance and
4800 We will eventually provide full debugging of g++ output on
4801 DECstations. This will probably involve some kind of stabs-in-ecoff
4802 encapulation, but the details have not been worked out yet.
4805 *** Changes in GDB-4.2:
4807 * Improved configuration
4809 Only one copy of `configure' exists now, and it is not self-modifying.
4810 Porting BFD is simpler.
4814 The `step' and `next' commands now only stop at the first instruction
4815 of a source line. This prevents the multiple stops that used to occur
4816 in switch statements, for-loops, etc. `Step' continues to stop if a
4817 function that has debugging information is called within the line.
4821 Lots of small bugs fixed. More remain.
4823 * New host supported (not target)
4825 Intel 386 PC clone running Mach i386-none-mach
4828 *** Changes in GDB-4.1:
4830 * Multiple source language support
4832 GDB now has internal scaffolding to handle several source languages.
4833 It determines the type of each source file from its filename extension,
4834 and will switch expression parsing and number formatting to match the
4835 language of the function in the currently selected stack frame.
4836 You can also specifically set the language to be used, with
4837 `set language c' or `set language modula-2'.
4841 GDB now has preliminary support for the GNU Modula-2 compiler,
4842 currently under development at the State University of New York at
4843 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4844 continue through the fall of 1991 and into 1992.
4846 Other Modula-2 compilers are currently not supported, and attempting to
4847 debug programs compiled with them will likely result in an error as the
4848 symbol table is read. Feel free to work on it, though!
4850 There are hooks in GDB for strict type checking and range checking,
4851 in the `Modula-2 philosophy', but they do not currently work.
4855 GDB can now write to executable and core files (e.g. patch
4856 a variable's value). You must turn this switch on, specify
4857 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4858 by assigning a new value to a variable. Modifications take
4861 * Automatic SunOS shared library reading
4863 When you run your program, GDB automatically determines where its
4864 shared libraries (if any) have been loaded, and reads their symbols.
4865 The `share' command is no longer needed. This also works when
4866 examining core files.
4870 You can specify the number of lines that the `list' command shows.
4873 * New machines supported (host and target)
4875 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4876 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4877 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4879 * New hosts supported (not targets)
4881 IBM RT/PC: romp-ibm-aix or rtpc
4883 * New targets supported (not hosts)
4885 AMD 29000 embedded with COFF a29k-none-coff
4886 AMD 29000 embedded with a.out a29k-none-aout
4887 Ultracomputer remote kernel debug a29k-nyu-kern
4889 * New remote interfaces
4895 *** Changes in GDB-4.0:
4899 Wide output is wrapped at good places to make the output more readable.
4901 Gdb now supports cross-debugging from a host machine of one type to a
4902 target machine of another type. Communication with the target system
4903 is over serial lines. The ``target'' command handles connecting to the
4904 remote system; the ``load'' command will download a program into the
4905 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4906 also supports debugging of realtime processes running under VxWorks,
4907 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4908 stub on the target system.
4910 New CPUs supported include the AMD 29000 and Intel 960.
4912 GDB now reads object files and symbol tables via a ``binary file''
4913 library, which allows a single copy of GDB to debug programs of multiple
4914 object file types such as a.out and coff.
4916 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4917 refcard.dvi and refcard.ps are available to format it).
4920 * Control-Variable user interface simplified
4922 All variables that control the operation of the debugger can be set
4923 by the ``set'' command, and displayed by the ``show'' command.
4925 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4926 ``Show prompt'' produces the response:
4927 Gdb's prompt is new-gdb=>.
4929 What follows are the NEW set commands. The command ``help set'' will
4930 print a complete list of old and new set commands. ``help set FOO''
4931 will give a longer description of the variable FOO. ``show'' will show
4932 all of the variable descriptions and their current settings.
4934 confirm on/off: Enables warning questions for operations that are
4935 hard to recover from, e.g. rerunning the program while
4936 it is already running. Default is ON.
4938 editing on/off: Enables EMACS style command line editing
4939 of input. Previous lines can be recalled with
4940 control-P, the current line can be edited with control-B,
4941 you can search for commands with control-R, etc.
4944 history filename NAME: NAME is where the gdb command history
4945 will be stored. The default is .gdb_history,
4946 or the value of the environment variable
4949 history size N: The size, in commands, of the command history. The
4950 default is 256, or the value of the environment variable
4953 history save on/off: If this value is set to ON, the history file will
4954 be saved after exiting gdb. If set to OFF, the
4955 file will not be saved. The default is OFF.
4957 history expansion on/off: If this value is set to ON, then csh-like
4958 history expansion will be performed on
4959 command line input. The default is OFF.
4961 radix N: Sets the default radix for input and output. It can be set
4962 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4963 in the current radix, so "set radix 10" is always a no-op.
4965 height N: This integer value is the number of lines on a page. Default
4966 is 24, the current `stty rows'' setting, or the ``li#''
4967 setting from the termcap entry matching the environment
4970 width N: This integer value is the number of characters on a line.
4971 Default is 80, the current `stty cols'' setting, or the ``co#''
4972 setting from the termcap entry matching the environment
4975 Note: ``set screensize'' is obsolete. Use ``set height'' and
4976 ``set width'' instead.
4978 print address on/off: Print memory addresses in various command displays,
4979 such as stack traces and structure values. Gdb looks
4980 more ``symbolic'' if you turn this off; it looks more
4981 ``machine level'' with it on. Default is ON.
4983 print array on/off: Prettyprint arrays. New convenient format! Default
4986 print demangle on/off: Print C++ symbols in "source" form if on,
4989 print asm-demangle on/off: Same, for assembler level printouts
4992 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4995 * Support for Epoch Environment.
4997 The epoch environment is a version of Emacs v18 with windowing. One
4998 new command, ``inspect'', is identical to ``print'', except that if you
4999 are running in the epoch environment, the value is printed in its own
5003 * Support for Shared Libraries
5005 GDB can now debug programs and core files that use SunOS shared libraries.
5006 Symbols from a shared library cannot be referenced
5007 before the shared library has been linked with the program (this
5008 happens after you type ``run'' and before the function main() is entered).
5009 At any time after this linking (including when examining core files
5010 from dynamically linked programs), gdb reads the symbols from each
5011 shared library when you type the ``sharedlibrary'' command.
5012 It can be abbreviated ``share''.
5014 sharedlibrary REGEXP: Load shared object library symbols for files
5015 matching a unix regular expression. No argument
5016 indicates to load symbols for all shared libraries.
5018 info sharedlibrary: Status of loaded shared libraries.
5023 A watchpoint stops execution of a program whenever the value of an
5024 expression changes. Checking for this slows down execution
5025 tremendously whenever you are in the scope of the expression, but is
5026 quite useful for catching tough ``bit-spreader'' or pointer misuse
5027 problems. Some machines such as the 386 have hardware for doing this
5028 more quickly, and future versions of gdb will use this hardware.
5030 watch EXP: Set a watchpoint (breakpoint) for an expression.
5032 info watchpoints: Information about your watchpoints.
5034 delete N: Deletes watchpoint number N (same as breakpoints).
5035 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5036 enable N: Re-enables watchpoint number N (same as breakpoints).
5039 * C++ multiple inheritance
5041 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5044 * C++ exception handling
5046 Gdb now supports limited C++ exception handling. Besides the existing
5047 ability to breakpoint on an exception handler, gdb can breakpoint on
5048 the raising of an exception (before the stack is peeled back to the
5051 catch FOO: If there is a FOO exception handler in the dynamic scope,
5052 set a breakpoint to catch exceptions which may be raised there.
5053 Multiple exceptions (``catch foo bar baz'') may be caught.
5055 info catch: Lists all exceptions which may be caught in the
5056 current stack frame.
5059 * Minor command changes
5061 The command ``call func (arg, arg, ...)'' now acts like the print
5062 command, except it does not print or save a value if the function's result
5063 is void. This is similar to dbx usage.
5065 The ``up'' and ``down'' commands now always print the frame they end up
5066 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5067 frames without printing.
5069 * New directory command
5071 'dir' now adds directories to the FRONT of the source search path.
5072 The path starts off empty. Source files that contain debug information
5073 about the directory in which they were compiled can be found even
5074 with an empty path; Sun CC and GCC include this information. If GDB can't
5075 find your source file in the current directory, type "dir .".
5077 * Configuring GDB for compilation
5079 For normal use, type ``./configure host''. See README or gdb.texinfo
5082 GDB now handles cross debugging. If you are remotely debugging between
5083 two different machines, type ``./configure host -target=targ''.
5084 Host is the machine where GDB will run; targ is the machine
5085 where the program that you are debugging will run.