1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.5
6 * New commands (for set/show, see "New options" below)
9 List the BFDs known to GDB.
11 *** Changes in GDB 7.5
13 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
14 for more x32 ABI info.
16 * GDB now supports access to MIPS DSP registers on Linux targets.
18 * GDB now supports debugging microMIPS binaries.
20 * The "info os" command on GNU/Linux can now display information on
21 several new classes of objects managed by the operating system:
22 "info os procgroups" lists process groups
23 "info os files" lists file descriptors
24 "info os sockets" lists internet-domain sockets
25 "info os shm" lists shared-memory regions
26 "info os semaphores" lists semaphores
27 "info os msg" lists message queues
28 "info os modules" lists loaded kernel modules
30 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
31 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
32 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
33 options and inspect the probe arguments using the new $_probe_arg family
34 of convenience variables. You can obtain more information about SystemTap
35 in <http://sourceware.org/systemtap/>.
37 * GDB now supports reversible debugging on ARM, it allows you to
38 debug basic ARM and THUMB instructions, and provides
39 record/replay support.
41 * The option "symbol-reloading" has been deleted as it is no longer used.
45 ** GDB commands implemented in Python can now be put in command class
48 ** The "maint set python print-stack on|off" is now deleted.
50 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
51 apply "flag enum"-style pretty-printing to any enum.
53 ** gdb.lookup_symbol can now work when there is no current frame.
55 ** gdb.Symbol now has a 'line' attribute, holding the line number in
56 the source at which the symbol was defined.
58 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
59 method 'value'. The former indicates whether the symbol needs a
60 frame in order to compute its value, and the latter computes the
63 ** A new method 'referenced_value' on gdb.Value objects which can
64 dereference pointer as well as C++ reference values.
66 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
67 which return the global and static blocks (as gdb.Block objects),
68 of the underlying symbol table, respectively.
70 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
71 object associated with a PC value.
73 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
74 of the address range occupied by code for the current source line.
76 * Go language support.
77 GDB now supports debugging programs written in the Go programming
80 * GDBserver now supports stdio connections.
81 E.g. (gdb) target remote | ssh myhost gdbserver - hello
83 * The binary "gdbtui" can no longer be built or installed.
84 Use "gdb -tui" instead.
86 * GDB will now print "flag" enums specially. A flag enum is one where
87 all the enumerator values have no bits in common when pairwise
88 "and"ed. When printing a value whose type is a flag enum, GDB will
89 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
90 (gdb) print (enum E) 3
93 * The filename part of a linespec will now match trailing components
94 of a source file name. For example, "break gcc/expr.c:1000" will
95 now set a breakpoint in build/gcc/expr.c, but not
98 * The "info proc" and "generate-core-file" commands will now also
99 work on remote targets connected to GDBserver on Linux.
101 * The command "info catch" has been removed. It has been disabled
104 * The "catch exception" and "catch assert" commands now accept
105 a condition at the end of the command, much like the "break"
106 command does. For instance:
108 (gdb) catch exception Constraint_Error if Barrier = True
110 Previously, it was possible to add a condition to such catchpoints,
111 but it had to be done as a second step, after the catchpoint had been
112 created, using the "condition" command.
114 * The "info static-tracepoint-marker" command will now also work on
115 native Linux targets with in-process agent.
117 * GDB can now set breakpoints on inlined functions.
119 * The .gdb_index section has been updated to include symbols for
120 inlined functions. GDB will ignore older .gdb_index sections by
121 default, which could cause symbol files to be loaded more slowly
122 until their .gdb_index sections can be recreated. The new command
123 "set use-deprecated-index-sections on" will cause GDB to use any older
124 .gdb_index sections it finds. This will restore performance, but the
125 ability to set breakpoints on inlined functions will be lost in symbol
126 files with older .gdb_index sections.
128 The .gdb_index section has also been updated to record more information
129 about each symbol. This speeds up the "info variables", "info functions"
130 and "info types" commands when used with programs having the .gdb_index
131 section, as well as speeding up debugging with shared libraries using
132 the .gdb_index section.
134 * Ada support for GDB/MI Variable Objects has been added.
136 * GDB can now support 'breakpoint always-inserted mode' in 'record'
141 ** New command -info-os is the MI equivalent of "info os".
143 ** Output logs ("set logging" and related) now include MI output.
147 ** "set use-deprecated-index-sections on|off"
148 "show use-deprecated-index-sections on|off"
149 Controls the use of deprecated .gdb_index sections.
151 ** "catch load" and "catch unload" can be used to stop when a shared
152 library is loaded or unloaded, respectively.
154 ** "enable count" can be used to auto-disable a breakpoint after
157 ** "info vtbl" can be used to show the virtual method tables for
158 C++ and Java objects.
160 ** "explore" and its sub commands "explore value" and "explore type"
161 can be used to reccursively explore values and types of
162 expressions. These commands are available only if GDB is
163 configured with '--with-python'.
165 ** "info auto-load" shows status of all kinds of auto-loaded files,
166 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
167 sequences of commands files, "info auto-load python-scripts"
168 shows status of auto-loading Python script files,
169 "info auto-load local-gdbinit" shows status of loading init file
170 (.gdbinit) from current directory and "info auto-load libthread-db" shows
171 status of inferior specific thread debugging shared library loading.
173 ** "info auto-load-scripts", "set auto-load-scripts on|off"
174 and "show auto-load-scripts" commands have been deprecated, use their
175 "info auto-load python-scripts", "set auto-load python-scripts on|off"
176 and "show auto-load python-scripts" counterparts instead.
178 ** "dprintf location,format,args..." creates a dynamic printf, which
179 is basically a breakpoint that does a printf and immediately
180 resumes your program's execution, so it is like a printf that you
181 can insert dynamically at runtime instead of at compiletime.
183 ** "set print symbol"
185 Controls whether GDB attempts to display the symbol, if any,
186 corresponding to addresses it prints. This defaults to "on", but
187 you can set it to "off" to restore GDB's previous behavior.
189 * Deprecated commands
191 ** For the Renesas Super-H architecture, the "regs" command has been
192 deprecated, and "info all-registers" should be used instead.
196 Renesas RL78 rl78-*-elf
197 HP OpenVMS ia64 ia64-hp-openvms*
199 * GDBserver supports evaluation of breakpoint conditions. When
200 support is advertised by GDBserver, GDB may be told to send the
201 breakpoint conditions in bytecode form to GDBserver. GDBserver
202 will only report the breakpoint trigger to GDB when its condition
208 show mips compression
209 Select the compressed ISA encoding used in functions that have no symbol
210 information available. The encoding can be set to either of:
213 and is updated automatically from ELF file flags if available.
215 set breakpoint condition-evaluation
216 show breakpoint condition-evaluation
217 Control whether breakpoint conditions are evaluated by GDB ("host") or by
218 GDBserver ("target"). Default option "auto" chooses the most efficient
220 This option can improve debugger efficiency depending on the speed of the
224 Disable auto-loading globally.
227 Show auto-loading setting of all kinds of auto-loaded files.
229 set auto-load gdb-scripts on|off
230 show auto-load gdb-scripts
231 Control auto-loading of GDB canned sequences of commands files.
233 set auto-load python-scripts on|off
234 show auto-load python-scripts
235 Control auto-loading of Python script files.
237 set auto-load local-gdbinit on|off
238 show auto-load local-gdbinit
239 Control loading of init file (.gdbinit) from current directory.
241 set auto-load libthread-db on|off
242 show auto-load libthread-db
243 Control auto-loading of inferior specific thread debugging shared library.
245 set auto-load scripts-directory <dir1>[:<dir2>...]
246 show auto-load scripts-directory
247 Set a list of directories from which to load auto-loaded scripts.
248 Automatically loaded Python scripts and GDB scripts are located in one
249 of the directories listed by this option.
250 The delimiter (':' above) may differ according to the host platform.
252 set auto-load safe-path <dir1>[:<dir2>...]
253 show auto-load safe-path
254 Set a list of directories from which it is safe to auto-load files.
255 The delimiter (':' above) may differ according to the host platform.
257 set debug auto-load on|off
259 Control display of debugging info for auto-loading the files above.
261 set dprintf-style gdb|call|agent
263 Control the way in which a dynamic printf is performed; "gdb"
264 requests a GDB printf command, while "call" causes dprintf to call a
265 function in the inferior. "agent" requests that the target agent
266 (such as GDBserver) do the printing.
268 set dprintf-function <expr>
269 show dprintf-function
270 set dprintf-channel <expr>
272 Set the function and optional first argument to the call when using
273 the "call" style of dynamic printf.
275 set disconnected-dprintf on|off
276 show disconnected-dprintf
277 Control whether agent-style dynamic printfs continue to be in effect
278 after GDB disconnects.
280 * New configure options
283 Configure default value for the 'set auto-load scripts-directory'
284 setting above. It defaults to '$debugdir:$datadir/auto-load',
285 $debugdir representing global debugging info directories (available
286 via 'show debug-file-directory') and $datadir representing GDB's data
287 directory (available via 'show data-directory').
289 --with-auto-load-safe-path
290 Configure default value for the 'set auto-load safe-path' setting
291 above. It defaults to the --with-auto-load-dir setting.
293 --without-auto-load-safe-path
294 Set 'set auto-load safe-path' to '/', effectively disabling this
299 z0/z1 conditional breakpoints extension
301 The z0/z1 breakpoint insertion packets have been extended to carry
302 a list of conditional expressions over to the remote stub depending on the
303 condition evaluation mode. The use of this extension can be controlled
304 via the "set remote conditional-breakpoints-packet" command.
308 Specify the signals which the remote stub may pass to the debugged
309 program without GDB involvement.
311 * New command line options
313 --init-command=FILE, -ix Like --command, -x but execute it
314 before loading inferior.
315 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
316 execute it before loading inferior.
318 *** Changes in GDB 7.4
320 * GDB now handles ambiguous linespecs more consistently; the existing
321 FILE:LINE support has been expanded to other types of linespecs. A
322 breakpoint will now be set on all matching locations in all
323 inferiors, and locations will be added or removed according to
326 * GDB now allows you to skip uninteresting functions and files when
327 stepping with the "skip function" and "skip file" commands.
329 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
330 and "show remote hardware-watchpoint-length-limit". These allows to
331 set or show the maximum length limit (in bytes) of a remote
332 target hardware watchpoint.
334 This allows e.g. to use "unlimited" hardware watchpoints with the
335 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
336 watchpoints are slower than real hardware watchpoints but are
337 significantly faster than gdb software watchpoints.
341 ** The register_pretty_printer function in module gdb.printing now takes
342 an optional `replace' argument. If True, the new printer replaces any
345 ** The "maint set python print-stack on|off" command has been
346 deprecated and will be deleted in GDB 7.5.
347 A new command: "set python print-stack none|full|message" has
348 replaced it. Additionally, the default for "print-stack" is
349 now "message", which just prints the error message without
352 ** A prompt substitution hook (prompt_hook) is now available to the
355 ** A new Python module, gdb.prompt has been added to the GDB Python
356 modules library. This module provides functionality for
357 escape sequences in prompts (used by set/show
358 extended-prompt). These escape sequences are replaced by their
361 ** Python commands and convenience-functions located in
362 'data-directory'/python/gdb/command and
363 'data-directory'/python/gdb/function are now automatically loaded
366 ** Blocks now provide four new attributes. global_block and
367 static_block will return the global and static blocks
368 respectively. is_static and is_global are boolean attributes
369 that indicate if the block is one of those two types.
371 ** Symbols now provide the "type" attribute, the type of the symbol.
373 ** The "gdb.breakpoint" function has been deprecated in favor of
376 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
377 of a function. This class is based on the "finish" command
378 available in the CLI.
380 ** Type objects for struct and union types now allow access to
381 the fields using standard Python dictionary (mapping) methods.
382 For example, "some_type['myfield']" now works, as does
385 ** A new event "gdb.new_objfile" has been added, triggered by loading a
388 ** A new function, "deep_items" has been added to the gdb.types
389 module in the GDB Python modules library. This function returns
390 an iterator over the fields of a struct or union type. Unlike
391 the standard Python "iteritems" method, it will recursively traverse
392 any anonymous fields.
396 ** "*stopped" events can report several new "reason"s, such as
399 ** Breakpoint changes are now notified using new async records, like
400 "=breakpoint-modified".
402 ** New command -ada-task-info.
404 * libthread-db-search-path now supports two special values: $sdir and $pdir.
405 $sdir specifies the default system locations of shared libraries.
406 $pdir specifies the directory where the libpthread used by the application
409 GDB no longer looks in $sdir and $pdir after it has searched the directories
410 mentioned in libthread-db-search-path. If you want to search those
411 directories, they must be specified in libthread-db-search-path.
412 The default value of libthread-db-search-path on GNU/Linux and Solaris
413 systems is now "$sdir:$pdir".
415 $pdir is not supported by gdbserver, it is currently ignored.
416 $sdir is supported by gdbserver.
418 * New configure option --with-iconv-bin.
419 When using the internationalization support like the one in the GNU C
420 library, GDB will invoke the "iconv" program to get a list of supported
421 character sets. If this program lives in a non-standard location, one can
422 use this option to specify where to find it.
424 * When natively debugging programs on PowerPC BookE processors running
425 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
426 watchpoints, which specify a mask in addition to an address to watch.
427 The mask specifies that some bits of an address (the bits which are
428 reset in the mask) should be ignored when matching the address accessed
429 by the inferior against the watchpoint address. See the "PowerPC Embedded"
430 section in the user manual for more details.
432 * The new option --once causes GDBserver to stop listening for connections once
433 the first connection is made. The listening port used by GDBserver will
434 become available after that.
436 * New commands "info macros" and "alias" have been added.
438 * New function parameters suffix @entry specifies value of function parameter
439 at the time the function got called. Entry values are available only since
445 "!" is now an alias of the "shell" command.
446 Note that no space is needed between "!" and SHELL COMMAND.
450 watch EXPRESSION mask MASK_VALUE
451 The watch command now supports the mask argument which allows creation
452 of masked watchpoints, if the current architecture supports this feature.
454 info auto-load-scripts [REGEXP]
455 This command was formerly named "maintenance print section-scripts".
456 It is now generally useful and is no longer a maintenance-only command.
458 info macro [-all] [--] MACRO
459 The info macro command has new options `-all' and `--'. The first for
460 printing all definitions of a macro. The second for explicitly specifying
461 the end of arguments and the beginning of the macro name in case the macro
462 name starts with a hyphen.
464 collect[/s] EXPRESSIONS
465 The tracepoint collect command now takes an optional modifier "/s"
466 that directs it to dereference pointer-to-character types and
467 collect the bytes of memory up to a zero byte. The behavior is
468 similar to what you see when you use the regular print command on a
469 string. An optional integer following the "/s" sets a bound on the
470 number of bytes that will be collected.
473 The trace start command now interprets any supplied arguments as a
474 note to be recorded with the trace run, with an effect similar to
475 setting the variable trace-notes.
478 The trace stop command now interprets any arguments as a note to be
479 mentioned along with the tstatus report that the trace was stopped
480 with a command. The effect is similar to setting the variable
483 * Tracepoints can now be enabled and disabled at any time after a trace
484 experiment has been started using the standard "enable" and "disable"
485 commands. It is now possible to start a trace experiment with no enabled
486 tracepoints; GDB will display a warning, but will allow the experiment to
487 begin, assuming that tracepoints will be enabled as needed while the trace
490 * Fast tracepoints on 32-bit x86-architectures can now be placed at
491 locations with 4-byte instructions, when they were previously
492 limited to locations with instructions of 5 bytes or longer.
496 set debug dwarf2-read
497 show debug dwarf2-read
498 Turns on or off display of debugging messages related to reading
499 DWARF debug info. The default is off.
501 set debug symtab-create
502 show debug symtab-create
503 Turns on or off display of debugging messages related to symbol table
504 creation. The default is off.
508 Set the GDB prompt, and allow escape sequences to be inserted to
509 display miscellaneous information (see 'help set extended-prompt'
510 for the list of sequences). This prompt (and any information
511 accessed through the escape sequences) is updated every time the
514 set print entry-values (both|compact|default|if-needed|no|only|preferred)
515 show print entry-values
516 Set printing of frame argument values at function entry. In some cases
517 GDB can determine the value of function argument which was passed by the
518 function caller, even if the value was modified inside the called function.
520 set debug entry-values
521 show debug entry-values
522 Control display of debugging info for determining frame argument values at
523 function entry and virtual tail call frames.
525 set basenames-may-differ
526 show basenames-may-differ
527 Set whether a source file may have multiple base names.
528 (A "base name" is the name of a file with the directory part removed.
529 Example: The base name of "/home/user/hello.c" is "hello.c".)
530 If set, GDB will canonicalize file names (e.g., expand symlinks)
531 before comparing them. Canonicalization is an expensive operation,
532 but it allows the same file be known by more than one base name.
533 If not set (the default), all source files are assumed to have just
534 one base name, and gdb will do file name comparisons more efficiently.
540 Set a user name and notes for the current and any future trace runs.
541 This is useful for long-running and/or disconnected traces, to
542 inform others (or yourself) as to who is running the trace, supply
543 contact information, or otherwise explain what is going on.
546 show trace-stop-notes
547 Set a note attached to the trace run, that is displayed when the
548 trace has been stopped by a tstop command. This is useful for
549 instance as an explanation, if you are stopping a trace run that was
550 started by someone else.
556 Dynamically enable a tracepoint in a started trace experiment.
560 Dynamically disable a tracepoint in a started trace experiment.
564 Set the user and notes of the trace run.
568 Query the current status of a tracepoint.
572 Query the minimum length of instruction at which a fast tracepoint may
575 * Dcache size (number of lines) and line-size are now runtime-configurable
576 via "set dcache line" and "set dcache line-size" commands.
580 Texas Instruments TMS320C6x tic6x-*-*
584 Renesas RL78 rl78-*-elf
586 *** Changes in GDB 7.3.1
588 * The build failure for NetBSD and OpenBSD targets have now been fixed.
590 *** Changes in GDB 7.3
592 * GDB has a new command: "thread find [REGEXP]".
593 It finds the thread id whose name, target id, or thread extra info
594 matches the given regular expression.
596 * The "catch syscall" command now works on mips*-linux* targets.
598 * The -data-disassemble MI command now supports modes 2 and 3 for
599 dumping the instruction opcodes.
601 * New command line options
603 -data-directory DIR Specify DIR as the "data-directory".
604 This is mostly for testing purposes.
606 * The "maint set python auto-load on|off" command has been renamed to
607 "set auto-load-scripts on|off".
609 * GDB has a new command: "set directories".
610 It is like the "dir" command except that it replaces the
611 source path list instead of augmenting it.
613 * GDB now understands thread names.
615 On GNU/Linux, "info threads" will display the thread name as set by
616 prctl or pthread_setname_np.
618 There is also a new command, "thread name", which can be used to
619 assign a name internally for GDB to display.
622 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
623 has been integrated into GDB.
627 ** The function gdb.Write now accepts an optional keyword 'stream'.
628 This keyword, when provided, will direct the output to either
629 stdout, stderr, or GDB's logging output.
631 ** Parameters can now be be sub-classed in Python, and in particular
632 you may implement the get_set_doc and get_show_doc functions.
633 This improves how Parameter set/show documentation is processed
634 and allows for more dynamic content.
636 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
637 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
638 have an is_valid method.
640 ** Breakpoints can now be sub-classed in Python, and in particular
641 you may implement a 'stop' function that is executed each time
642 the inferior reaches that breakpoint.
644 ** New function gdb.lookup_global_symbol looks up a global symbol.
646 ** GDB values in Python are now callable if the value represents a
647 function. For example, if 'some_value' represents a function that
648 takes two integer parameters and returns a value, you can call
649 that function like so:
651 result = some_value (10,20)
653 ** Module gdb.types has been added.
654 It contains a collection of utilities for working with gdb.Types objects:
655 get_basic_type, has_field, make_enum_dict.
657 ** Module gdb.printing has been added.
658 It contains utilities for writing and registering pretty-printers.
659 New classes: PrettyPrinter, SubPrettyPrinter,
660 RegexpCollectionPrettyPrinter.
661 New function: register_pretty_printer.
663 ** New commands "info pretty-printers", "enable pretty-printer" and
664 "disable pretty-printer" have been added.
666 ** gdb.parameter("directories") is now available.
668 ** New function gdb.newest_frame returns the newest frame in the
671 ** The gdb.InferiorThread class has a new "name" attribute. This
672 holds the thread's name.
674 ** Python Support for Inferior events.
675 Python scripts can add observers to be notified of events
676 occurring in the process being debugged.
677 The following events are currently supported:
678 - gdb.events.cont Continue event.
679 - gdb.events.exited Inferior exited event.
680 - gdb.events.stop Signal received, and Breakpoint hit events.
684 ** GDB now puts template parameters in scope when debugging in an
685 instantiation. For example, if you have:
687 template<int X> int func (void) { return X; }
689 then if you step into func<5>, "print X" will show "5". This
690 feature requires proper debuginfo support from the compiler; it
691 was added to GCC 4.5.
693 ** The motion commands "next", "finish", "until", and "advance" now
694 work better when exceptions are thrown. In particular, GDB will
695 no longer lose control of the inferior; instead, the GDB will
696 stop the inferior at the point at which the exception is caught.
697 This functionality requires a change in the exception handling
698 code that was introduced in GCC 4.5.
700 * GDB now follows GCC's rules on accessing volatile objects when
701 reading or writing target state during expression evaluation.
702 One notable difference to prior behavior is that "print x = 0"
703 no longer generates a read of x; the value of the assignment is
704 now always taken directly from the value being assigned.
706 * GDB now has some support for using labels in the program's source in
707 linespecs. For instance, you can use "advance label" to continue
708 execution to a label.
710 * GDB now has support for reading and writing a new .gdb_index
711 section. This section holds a fast index of DWARF debugging
712 information and can be used to greatly speed up GDB startup and
713 operation. See the documentation for `save gdb-index' for details.
715 * The "watch" command now accepts an optional "-location" argument.
716 When used, this causes GDB to watch the memory referred to by the
717 expression. Such a watchpoint is never deleted due to it going out
720 * GDB now supports thread debugging of core dumps on GNU/Linux.
722 GDB now activates thread debugging using the libthread_db library
723 when debugging GNU/Linux core dumps, similarly to when debugging
724 live processes. As a result, when debugging a core dump file, GDB
725 is now able to display pthread_t ids of threads. For example, "info
726 threads" shows the same output as when debugging the process when it
727 was live. In earlier releases, you'd see something like this:
730 * 1 LWP 6780 main () at main.c:10
732 While now you see this:
735 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
737 It is also now possible to inspect TLS variables when debugging core
740 When debugging a core dump generated on a machine other than the one
741 used to run GDB, you may need to point GDB at the correct
742 libthread_db library with the "set libthread-db-search-path"
743 command. See the user manual for more details on this command.
745 * When natively debugging programs on PowerPC BookE processors running
746 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
747 which stop execution of the inferior whenever it executes an instruction
748 at any address within the specified range. See the "PowerPC Embedded"
749 section in the user manual for more details.
751 * New features in the GDB remote stub, GDBserver
753 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
754 and i686 LynxOS (version 5.x).
756 ** GDBserver is now supported on Blackfin Linux.
758 * New native configurations
760 ia64 HP-UX ia64-*-hpux*
764 Analog Devices, Inc. Blackfin Processor bfin-*
766 * Ada task switching is now supported on sparc-elf targets when
767 debugging a program using the Ravenscar Profile. For more information,
768 see the "Tasking Support when using the Ravenscar Profile" section
769 in the GDB user manual.
771 * Guile support was removed.
773 * New features in the GNU simulator
775 ** The --map-info flag lists all known core mappings.
777 ** CFI flashes may be simulated via the "cfi" device.
779 *** Changes in GDB 7.2
781 * Shared library support for remote targets by default
783 When GDB is configured for a generic, non-OS specific target, like
784 for example, --target=arm-eabi or one of the many *-*-elf targets,
785 GDB now queries remote stubs for loaded shared libraries using the
786 `qXfer:libraries:read' packet. Previously, shared library support
787 was always disabled for such configurations.
791 ** Argument Dependent Lookup (ADL)
793 In C++ ADL lookup directs function search to the namespaces of its
794 arguments even if the namespace has not been imported.
804 Here the compiler will search for `foo' in the namespace of 'b'
805 and find A::foo. GDB now supports this. This construct is commonly
806 used in the Standard Template Library for operators.
808 ** Improved User Defined Operator Support
810 In addition to member operators, GDB now supports lookup of operators
811 defined in a namespace and imported with a `using' directive, operators
812 defined in the global scope, operators imported implicitly from an
813 anonymous namespace, and the ADL operators mentioned in the previous
815 GDB now also supports proper overload resolution for all the previously
816 mentioned flavors of operators.
818 ** static const class members
820 Printing of static const class members that are initialized in the
821 class definition has been fixed.
823 * Windows Thread Information Block access.
825 On Windows targets, GDB now supports displaying the Windows Thread
826 Information Block (TIB) structure. This structure is visible either
827 by using the new command `info w32 thread-information-block' or, by
828 dereferencing the new convenience variable named `$_tlb', a
829 thread-specific pointer to the TIB. This feature is also supported
830 when remote debugging using GDBserver.
834 Static tracepoints are calls in the user program into a tracing
835 library. One such library is a port of the LTTng kernel tracer to
836 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
837 When debugging with GDBserver, GDB now supports combining the GDB
838 tracepoint machinery with such libraries. For example: the user can
839 use GDB to probe a static tracepoint marker (a call from the user
840 program into the tracing library) with the new "strace" command (see
841 "New commands" below). This creates a "static tracepoint" in the
842 breakpoint list, that can be manipulated with the same feature set
843 as fast and regular tracepoints. E.g., collect registers, local and
844 global variables, collect trace state variables, and define
845 tracepoint conditions. In addition, the user can collect extra
846 static tracepoint marker specific data, by collecting the new
847 $_sdata internal variable. When analyzing the trace buffer, you can
848 inspect $_sdata like any other variable available to GDB. For more
849 information, see the "Tracepoints" chapter in GDB user manual. New
850 remote packets have been defined to support static tracepoints, see
851 the "New remote packets" section below.
853 * Better reconstruction of tracepoints after disconnected tracing
855 GDB will attempt to download the original source form of tracepoint
856 definitions when starting a trace run, and then will upload these
857 upon reconnection to the target, resulting in a more accurate
858 reconstruction of the tracepoints that are in use on the target.
862 You can now exercise direct control over the ways that GDB can
863 affect your program. For instance, you can disallow the setting of
864 breakpoints, so that the program can run continuously (assuming
865 non-stop mode). In addition, the "observer" variable is available
866 to switch all of the different controls; in observer mode, GDB
867 cannot affect the target's behavior at all, which is useful for
868 tasks like diagnosing live systems in the field.
870 * The new convenience variable $_thread holds the number of the
877 Return the address of the Windows Thread Information Block of a given thread.
881 In response to several of the tracepoint packets, the target may now
882 also respond with a number of intermediate `qRelocInsn' request
883 packets before the final result packet, to have GDB handle
884 relocating an instruction to execute at a different address. This
885 is particularly useful for stubs that support fast tracepoints. GDB
886 reports support for this feature in the qSupported packet.
890 List static tracepoint markers in the target program.
894 List static tracepoint markers at a given address in the target
897 qXfer:statictrace:read
899 Read the static trace data collected (by a `collect $_sdata'
900 tracepoint action). The remote stub reports support for this packet
901 to gdb's qSupported query.
905 Send the current settings of GDB's permission flags.
909 Send part of the source (textual) form of a tracepoint definition,
910 which includes location, conditional, and action list.
912 * The source command now accepts a -s option to force searching for the
913 script in the source search path even if the script name specifies
916 * New features in the GDB remote stub, GDBserver
918 - GDBserver now support tracepoints (including fast tracepoints, and
919 static tracepoints). The feature is currently supported by the
920 i386-linux and amd64-linux builds. See the "Tracepoints support
921 in gdbserver" section in the manual for more information.
923 GDBserver JIT compiles the tracepoint's conditional agent
924 expression bytecode into native code whenever possible for low
925 overhead dynamic tracepoints conditionals. For such tracepoints,
926 an expression that examines program state is evaluated when the
927 tracepoint is reached, in order to determine whether to capture
928 trace data. If the condition is simple and false, processing the
929 tracepoint finishes very quickly and no data is gathered.
931 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
932 for static tracepoints support.
934 - GDBserver now supports x86_64 Windows 64-bit debugging.
936 * GDB now sends xmlRegisters= in qSupported packet to indicate that
937 it understands register description.
939 * The --batch flag now disables pagination and queries.
941 * X86 general purpose registers
943 GDB now supports reading/writing byte, word and double-word x86
944 general purpose registers directly. This means you can use, say,
945 $ah or $ax to refer, respectively, to the byte register AH and
946 16-bit word register AX that are actually portions of the 32-bit
947 register EAX or 64-bit register RAX.
949 * The `commands' command now accepts a range of breakpoints to modify.
950 A plain `commands' following a command that creates multiple
951 breakpoints affects all the breakpoints set by that command. This
952 applies to breakpoints set by `rbreak', and also applies when a
953 single `break' command creates multiple breakpoints (e.g.,
954 breakpoints on overloaded c++ functions).
956 * The `rbreak' command now accepts a filename specification as part of
957 its argument, limiting the functions selected by the regex to those
958 in the specified file.
960 * Support for remote debugging Windows and SymbianOS shared libraries
961 from Unix hosts has been improved. Non Windows GDB builds now can
962 understand target reported file names that follow MS-DOS based file
963 system semantics, such as file names that include drive letters and
964 use the backslash character as directory separator. This makes it
965 possible to transparently use the "set sysroot" and "set
966 solib-search-path" on Unix hosts to point as host copies of the
967 target's shared libraries. See the new command "set
968 target-file-system-kind" described below, and the "Commands to
969 specify files" section in the user manual for more information.
973 eval template, expressions...
974 Convert the values of one or more expressions under the control
975 of the string template to a command line, and call it.
977 set target-file-system-kind unix|dos-based|auto
978 show target-file-system-kind
979 Set or show the assumed file system kind for target reported file
982 save breakpoints <filename>
983 Save all current breakpoint definitions to a file suitable for use
984 in a later debugging session. To read the saved breakpoint
985 definitions, use the `source' command.
987 `save tracepoints' is a new alias for `save-tracepoints'. The latter
990 info static-tracepoint-markers
991 Display information about static tracepoint markers in the target.
993 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
994 Define a static tracepoint by probing a marker at the given
995 function, line, address, or marker ID.
999 Enable and disable observer mode.
1001 set may-write-registers on|off
1002 set may-write-memory on|off
1003 set may-insert-breakpoints on|off
1004 set may-insert-tracepoints on|off
1005 set may-insert-fast-tracepoints on|off
1006 set may-interrupt on|off
1007 Set individual permissions for GDB effects on the target. Note that
1008 some of these settings can have undesirable or surprising
1009 consequences, particularly when changed in the middle of a session.
1010 For instance, disabling the writing of memory can prevent
1011 breakpoints from being inserted, cause single-stepping to fail, or
1012 even crash your program, if you disable after breakpoints have been
1013 inserted. However, GDB should not crash.
1015 set record memory-query on|off
1016 show record memory-query
1017 Control whether to stop the inferior if memory changes caused
1018 by an instruction cannot be recorded.
1023 The disassemble command now supports "start,+length" form of two arguments.
1027 ** GDB now provides a new directory location, called the python directory,
1028 where Python scripts written for GDB can be installed. The location
1029 of that directory is <data-directory>/python, where <data-directory>
1030 is the GDB data directory. For more details, see section `Scripting
1031 GDB using Python' in the manual.
1033 ** The GDB Python API now has access to breakpoints, symbols, symbol
1034 tables, program spaces, inferiors, threads and frame's code blocks.
1035 Additionally, GDB Parameters can now be created from the API, and
1036 manipulated via set/show in the CLI.
1038 ** New functions gdb.target_charset, gdb.target_wide_charset,
1039 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1041 ** New exception gdb.GdbError.
1043 ** Pretty-printers are now also looked up in the current program space.
1045 ** Pretty-printers can now be individually enabled and disabled.
1047 ** GDB now looks for names of Python scripts to auto-load in a
1048 special section named `.debug_gdb_scripts', in addition to looking
1049 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1051 * Tracepoint actions were unified with breakpoint commands. In particular,
1052 there are no longer differences in "info break" output for breakpoints and
1053 tracepoints and the "commands" command can be used for both tracepoints and
1054 regular breakpoints.
1058 ARM Symbian arm*-*-symbianelf*
1060 * D language support.
1061 GDB now supports debugging programs written in the D programming
1064 * GDB now supports the extended ptrace interface for PowerPC which is
1065 available since Linux kernel version 2.6.34. This automatically enables
1066 any hardware breakpoints and additional hardware watchpoints available in
1067 the processor. The old ptrace interface exposes just one hardware
1068 watchpoint and no hardware breakpoints.
1070 * GDB is now able to use the Data Value Compare (DVC) register available on
1071 embedded PowerPC processors to implement in hardware simple watchpoint
1072 conditions of the form:
1074 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1076 This works in native GDB running on Linux kernels with the extended ptrace
1077 interface mentioned above.
1079 *** Changes in GDB 7.1
1083 ** Namespace Support
1085 GDB now supports importing of namespaces in C++. This enables the
1086 user to inspect variables from imported namespaces. Support for
1087 namepace aliasing has also been added. So, if a namespace is
1088 aliased in the current scope (e.g. namepace C=A; ) the user can
1089 print variables using the alias (e.g. (gdb) print C::x).
1093 All known bugs relating to the printing of virtual base class were
1094 fixed. It is now possible to call overloaded static methods using a
1099 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1100 and reinterpret_cast<> are now handled by the C++ expression parser.
1104 Xilinx MicroBlaze microblaze-*-*
1109 Xilinx MicroBlaze microblaze
1112 * Multi-program debugging.
1114 GDB now has support for multi-program (a.k.a. multi-executable or
1115 multi-exec) debugging. This allows for debugging multiple inferiors
1116 simultaneously each running a different program under the same GDB
1117 session. See "Debugging Multiple Inferiors and Programs" in the
1118 manual for more information. This implied some user visible changes
1119 in the multi-inferior support. For example, "info inferiors" now
1120 lists inferiors that are not running yet or that have exited
1121 already. See also "New commands" and "New options" below.
1123 * New tracing features
1125 GDB's tracepoint facility now includes several new features:
1127 ** Trace state variables
1129 GDB tracepoints now include support for trace state variables, which
1130 are variables managed by the target agent during a tracing
1131 experiment. They are useful for tracepoints that trigger each
1132 other, so for instance one tracepoint can count hits in a variable,
1133 and then a second tracepoint has a condition that is true when the
1134 count reaches a particular value. Trace state variables share the
1135 $-syntax of GDB convenience variables, and can appear in both
1136 tracepoint actions and condition expressions. Use the "tvariable"
1137 command to create, and "info tvariables" to view; see "Trace State
1138 Variables" in the manual for more detail.
1142 GDB now includes an option for defining fast tracepoints, which
1143 targets may implement more efficiently, such as by installing a jump
1144 into the target agent rather than a trap instruction. The resulting
1145 speedup can be by two orders of magnitude or more, although the
1146 tradeoff is that some program locations on some target architectures
1147 might not allow fast tracepoint installation, for instance if the
1148 instruction to be replaced is shorter than the jump. To request a
1149 fast tracepoint, use the "ftrace" command, with syntax identical to
1150 the regular trace command.
1152 ** Disconnected tracing
1154 It is now possible to detach GDB from the target while it is running
1155 a trace experiment, then reconnect later to see how the experiment
1156 is going. In addition, a new variable disconnected-tracing lets you
1157 tell the target agent whether to continue running a trace if the
1158 connection is lost unexpectedly.
1162 GDB now has the ability to save the trace buffer into a file, and
1163 then use that file as a target, similarly to you can do with
1164 corefiles. You can select trace frames, print data that was
1165 collected in them, and use tstatus to display the state of the
1166 tracing run at the moment that it was saved. To create a trace
1167 file, use "tsave <filename>", and to use it, do "target tfile
1170 ** Circular trace buffer
1172 You can ask the target agent to handle the trace buffer as a
1173 circular buffer, discarding the oldest trace frames to make room for
1174 newer ones, by setting circular-trace-buffer to on. This feature may
1175 not be available for all target agents.
1180 The disassemble command, when invoked with two arguments, now requires
1181 the arguments to be comma-separated.
1184 The info variables command now displays variable definitions. Files
1185 which only declare a variable are not shown.
1188 The source command is now capable of sourcing Python scripts.
1189 This feature is dependent on the debugger being build with Python
1192 Related to this enhancement is also the introduction of a new command
1193 "set script-extension" (see below).
1195 * New commands (for set/show, see "New options" below)
1197 record save [<FILENAME>]
1198 Save a file (in core file format) containing the process record
1199 execution log for replay debugging at a later time.
1201 record restore <FILENAME>
1202 Restore the process record execution log that was saved at an
1203 earlier time, for replay debugging.
1205 add-inferior [-copies <N>] [-exec <FILENAME>]
1208 clone-inferior [-copies <N>] [ID]
1209 Make a new inferior ready to execute the same program another
1210 inferior has loaded.
1215 maint info program-spaces
1216 List the program spaces loaded into GDB.
1218 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1219 show remote interrupt-sequence
1220 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1221 as the sequence to the remote target in order to interrupt the execution.
1222 Ctrl-C is a default. Some system prefers BREAK which is high level of
1223 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1224 Magic SysRq g. It is BREAK signal and character 'g'.
1226 set remote interrupt-on-connect [on | off]
1227 show remote interrupt-on-connect
1228 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1229 remote target when gdb connects to it. This is needed when you debug
1232 set remotebreak [on | off]
1234 Deprecated. Use "set/show remote interrupt-sequence" instead.
1236 tvariable $NAME [ = EXP ]
1237 Create or modify a trace state variable.
1240 List trace state variables and their values.
1242 delete tvariable $NAME ...
1243 Delete one or more trace state variables.
1246 Evaluate the given expressions without collecting anything into the
1247 trace buffer. (Valid in tracepoint actions only.)
1249 ftrace FN / FILE:LINE / *ADDR
1250 Define a fast tracepoint at the given function, line, or address.
1252 * New expression syntax
1254 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1255 GDB now parses 0b101010 identically with 42.
1259 set follow-exec-mode new|same
1260 show follow-exec-mode
1261 Control whether GDB reuses the same inferior across an exec call or
1262 creates a new one. This is useful to be able to restart the old
1263 executable after the inferior having done an exec call.
1265 set default-collect EXPR, ...
1266 show default-collect
1267 Define a list of expressions to be collected at each tracepoint.
1268 This is a useful way to ensure essential items are not overlooked,
1269 such as registers or a critical global variable.
1271 set disconnected-tracing
1272 show disconnected-tracing
1273 If set to 1, the target is instructed to continue tracing if it
1274 loses its connection to GDB. If 0, the target is to stop tracing
1277 set circular-trace-buffer
1278 show circular-trace-buffer
1279 If set to on, the target is instructed to use a circular trace buffer
1280 and discard the oldest trace frames instead of stopping the trace due
1281 to a full trace buffer. If set to off, the trace stops when the buffer
1282 fills up. Some targets may not support this.
1284 set script-extension off|soft|strict
1285 show script-extension
1286 If set to "off", the debugger does not perform any script language
1287 recognition, and all sourced files are assumed to be GDB scripts.
1288 If set to "soft" (the default), files are sourced according to
1289 filename extension, falling back to GDB scripts if the first
1291 If set to "strict", files are sourced according to filename extension.
1293 set ada trust-PAD-over-XVS on|off
1294 show ada trust-PAD-over-XVS
1295 If off, activate a workaround against a bug in the debugging information
1296 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1297 the GCC sources for more information about the GNAT encoding and
1298 PAD types in particular). It is always safe to set this option to
1299 off, but this introduces a slight performance penalty. The default
1302 * Python API Improvements
1304 ** GDB provides the new class gdb.LazyString. This is useful in
1305 some pretty-printing cases. The new method gdb.Value.lazy_string
1306 provides a simple way to create objects of this type.
1308 ** The fields returned by gdb.Type.fields now have an
1309 `is_base_class' attribute.
1311 ** The new method gdb.Type.range returns the range of an array type.
1313 ** The new method gdb.parse_and_eval can be used to parse and
1314 evaluate an expression.
1316 * New remote packets
1319 Define a trace state variable.
1322 Get the current value of a trace state variable.
1325 Set desired tracing behavior upon disconnection.
1328 Set the trace buffer to be linear or circular.
1331 Get data about the tracepoints currently in use.
1335 Process record now works correctly with hardware watchpoints.
1337 Multiple bug fixes have been made to the mips-irix port, making it
1338 much more reliable. In particular:
1339 - Debugging threaded applications is now possible again. Previously,
1340 GDB would hang while starting the program, or while waiting for
1341 the program to stop at a breakpoint.
1342 - Attaching to a running process no longer hangs.
1343 - An error occurring while loading a core file has been fixed.
1344 - Changing the value of the PC register now works again. This fixes
1345 problems observed when using the "jump" command, or when calling
1346 a function from GDB, or even when assigning a new value to $pc.
1347 - With the "finish" and "return" commands, the return value for functions
1348 returning a small array is now correctly printed.
1349 - It is now possible to break on shared library code which gets executed
1350 during a shared library init phase (code executed while executing
1351 their .init section). Previously, the breakpoint would have no effect.
1352 - GDB is now able to backtrace through the signal handler for
1353 non-threaded programs.
1355 PIE (Position Independent Executable) programs debugging is now supported.
1356 This includes debugging execution of PIC (Position Independent Code) shared
1357 libraries although for that, it should be possible to run such libraries as an
1360 *** Changes in GDB 7.0
1362 * GDB now has an interface for JIT compilation. Applications that
1363 dynamically generate code can create symbol files in memory and register
1364 them with GDB. For users, the feature should work transparently, and
1365 for JIT developers, the interface is documented in the GDB manual in the
1366 "JIT Compilation Interface" chapter.
1368 * Tracepoints may now be conditional. The syntax is as for
1369 breakpoints; either an "if" clause appended to the "trace" command,
1370 or the "condition" command is available. GDB sends the condition to
1371 the target for evaluation using the same bytecode format as is used
1372 for tracepoint actions.
1374 * The disassemble command now supports: an optional /r modifier, print the
1375 raw instructions in hex as well as in symbolic form, and an optional /m
1376 modifier to print mixed source+assembly.
1378 * Process record and replay
1380 In a architecture environment that supports ``process record and
1381 replay'', ``process record and replay'' target can record a log of
1382 the process execution, and replay it with both forward and reverse
1385 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1386 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1387 set execution-direction {forward|reverse}, for targets that support
1390 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1391 feature is available with a native GDB running on kernel version
1394 * GDB now has support for multi-byte and wide character sets on the
1395 target. Strings whose character type is wchar_t, char16_t, or
1396 char32_t are now correctly printed. GDB supports wide- and unicode-
1397 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1398 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1399 `printf'. This feature requires iconv to work properly; if your
1400 system does not have a working iconv, GDB can use GNU libiconv. See
1401 the installation instructions for more information.
1403 * GDB now supports automatic retrieval of shared library files from
1404 remote targets. To use this feature, specify a system root that begins
1405 with the `remote:' prefix, either via the `set sysroot' command or via
1406 the `--with-sysroot' configure-time option.
1408 * "info sharedlibrary" now takes an optional regex of libraries to show,
1409 and it now reports if a shared library has no debugging information.
1411 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1412 now complete on file names.
1414 * When completing in expressions, gdb will attempt to limit
1415 completions to allowable structure or union fields, where appropriate.
1416 For instance, consider:
1418 # struct example { int f1; double f2; };
1419 # struct example variable;
1422 If the user types TAB at the end of this command line, the available
1423 completions will be "f1" and "f2".
1425 * Inlined functions are now supported. They show up in backtraces, and
1426 the "step", "next", and "finish" commands handle them automatically.
1428 * GDB now supports the token-splicing (##) and stringification (#)
1429 operators when expanding macros. It also supports variable-arity
1432 * GDB now supports inspecting extra signal information, exported by
1433 the new $_siginfo convenience variable. The feature is currently
1434 implemented on linux ARM, i386 and amd64.
1436 * GDB can now display the VFP floating point registers and NEON vector
1437 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1438 can provide these registers (requires Linux 2.6.30 or later). Remote
1439 and simulator targets may also provide them.
1441 * New remote packets
1444 Search memory for a sequence of bytes.
1447 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1448 operation over reliable transport links. Use of this packet is
1449 controlled by the `set remote noack-packet' command.
1452 Kill the process with the specified process ID. Use this in preference
1453 to `k' when multiprocess protocol extensions are supported.
1456 Obtains additional operating system information
1460 Read or write additional signal information.
1462 * Removed remote protocol undocumented extension
1464 An undocumented extension to the remote protocol's `S' stop reply
1465 packet that permited the stub to pass a process id was removed.
1466 Remote servers should use the `T' stop reply packet instead.
1468 * GDB now supports multiple function calling conventions according to the
1469 DWARF-2 DW_AT_calling_convention function attribute.
1471 * The SH target utilizes the aforementioned change to distinguish between gcc
1472 and Renesas calling convention. It also adds the new CLI commands
1473 `set/show sh calling-convention'.
1475 * GDB can now read compressed debug sections, as produced by GNU gold
1476 with the --compress-debug-sections=zlib flag.
1478 * 64-bit core files are now supported on AIX.
1480 * Thread switching is now supported on Tru64.
1482 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1483 which will be allocated using malloc later in program execution.
1485 * The qXfer:libraries:read remote procotol packet now allows passing a
1486 list of section offsets.
1488 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1489 conditions handling signals delivered during attach or thread creation
1490 have also been fixed.
1492 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1493 From the user's standpoint, all unqualified instances of True and False
1494 are treated as the standard definitions, regardless of context.
1496 * GDB now parses C++ symbol and type names more flexibly. For
1499 template<typename T> class C { };
1502 GDB will now correctly handle all of:
1504 ptype C<char const *>
1505 ptype C<char const*>
1506 ptype C<const char *>
1507 ptype C<const char*>
1509 * New features in the GDB remote stub, gdbserver
1511 - The "--wrapper" command-line argument tells gdbserver to use a
1512 wrapper program to launch programs for debugging.
1514 - On PowerPC and S/390 targets, it is now possible to use a single
1515 gdbserver executable to debug both 32-bit and 64-bit programs.
1516 (This requires gdbserver itself to be built as a 64-bit executable.)
1518 - gdbserver uses the new noack protocol mode for TCP connections to
1519 reduce communications latency, if also supported and enabled in GDB.
1521 - Support for the sparc64-linux-gnu target is now included in
1524 - The amd64-linux build of gdbserver now supports debugging both
1525 32-bit and 64-bit programs.
1527 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1528 now support hardware watchpoints, and will use them automatically
1533 GDB now has support for scripting using Python. Whether this is
1534 available is determined at configure time.
1536 New GDB commands can now be written in Python.
1538 * Ada tasking support
1540 Ada tasks can now be inspected in GDB. The following commands have
1544 Print the list of Ada tasks.
1546 Print detailed information about task number N.
1548 Print the task number of the current task.
1550 Switch the context of debugging to task number N.
1552 * Support for user-defined prefixed commands. The "define" command can
1553 add new commands to existing prefixes, e.g. "target".
1555 * Multi-inferior, multi-process debugging.
1557 GDB now has generalized support for multi-inferior debugging. See
1558 "Debugging Multiple Inferiors" in the manual for more information.
1559 Although availability still depends on target support, the command
1560 set is more uniform now. The GNU/Linux specific multi-forks support
1561 has been migrated to this new framework. This implied some user
1562 visible changes; see "New commands" and also "Removed commands"
1565 * Target descriptions can now describe the target OS ABI. See the
1566 "Target Description Format" section in the user manual for more
1569 * Target descriptions can now describe "compatible" architectures
1570 to indicate that the target can execute applications for a different
1571 architecture in addition to those for the main target architecture.
1572 See the "Target Description Format" section in the user manual for
1575 * Multi-architecture debugging.
1577 GDB now includes general supports for debugging applications on
1578 hybrid systems that use more than one single processor architecture
1579 at the same time. Each such hybrid architecture still requires
1580 specific support to be added. The only hybrid architecture supported
1581 in this version of GDB is the Cell Broadband Engine.
1583 * GDB now supports integrated debugging of Cell/B.E. applications that
1584 use both the PPU and SPU architectures. To enable support for hybrid
1585 Cell/B.E. debugging, you need to configure GDB to support both the
1586 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1587 --enable-targets configure option.
1589 * Non-stop mode debugging.
1591 For some targets, GDB now supports an optional mode of operation in
1592 which you can examine stopped threads while other threads continue
1593 to execute freely. This is referred to as non-stop mode, with the
1594 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1595 section in the user manual for more information.
1597 To be able to support remote non-stop debugging, a remote stub needs
1598 to implement the non-stop mode remote protocol extensions, as
1599 described in the "Remote Non-Stop" section of the user manual. The
1600 GDB remote stub, gdbserver, has been adjusted to support these
1601 extensions on linux targets.
1603 * New commands (for set/show, see "New options" below)
1605 catch syscall [NAME(S) | NUMBER(S)]
1606 Catch system calls. Arguments, which should be names of system
1607 calls or their numbers, mean catch only those syscalls. Without
1608 arguments, every syscall will be caught. When the inferior issues
1609 any of the specified syscalls, GDB will stop and announce the system
1610 call, both when it is called and when its call returns. This
1611 feature is currently available with a native GDB running on the
1612 Linux Kernel, under the following architectures: x86, x86_64,
1613 PowerPC and PowerPC64.
1615 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1617 Search memory for a sequence of bytes.
1619 maint set python print-stack
1620 maint show python print-stack
1621 Show a stack trace when an error is encountered in a Python script.
1624 Invoke CODE by passing it to the Python interpreter.
1629 These allow macros to be defined, undefined, and listed
1633 Show operating system information about processes.
1636 List the inferiors currently under GDB's control.
1639 Switch focus to inferior number NUM.
1642 Detach from inferior number NUM.
1645 Kill inferior number NUM.
1649 set spu stop-on-load
1650 show spu stop-on-load
1651 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1653 set spu auto-flush-cache
1654 show spu auto-flush-cache
1655 Control whether to automatically flush the software-managed cache
1656 during Cell/B.E. debugging.
1658 set sh calling-convention
1659 show sh calling-convention
1660 Control the calling convention used when calling SH target functions.
1663 show debug timestamp
1664 Control display of timestamps with GDB debugging output.
1666 set disassemble-next-line
1667 show disassemble-next-line
1668 Control display of disassembled source lines or instructions when
1671 set remote noack-packet
1672 show remote noack-packet
1673 Set/show the use of remote protocol QStartNoAckMode packet. See above
1674 under "New remote packets."
1676 set remote query-attached-packet
1677 show remote query-attached-packet
1678 Control use of remote protocol `qAttached' (query-attached) packet.
1680 set remote read-siginfo-object
1681 show remote read-siginfo-object
1682 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1685 set remote write-siginfo-object
1686 show remote write-siginfo-object
1687 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1690 set remote reverse-continue
1691 show remote reverse-continue
1692 Control use of remote protocol 'bc' (reverse-continue) packet.
1694 set remote reverse-step
1695 show remote reverse-step
1696 Control use of remote protocol 'bs' (reverse-step) packet.
1698 set displaced-stepping
1699 show displaced-stepping
1700 Control displaced stepping mode. Displaced stepping is a way to
1701 single-step over breakpoints without removing them from the debuggee.
1702 Also known as "out-of-line single-stepping".
1705 show debug displaced
1706 Control display of debugging info for displaced stepping.
1708 maint set internal-error
1709 maint show internal-error
1710 Control what GDB does when an internal error is detected.
1712 maint set internal-warning
1713 maint show internal-warning
1714 Control what GDB does when an internal warning is detected.
1719 Use a wrapper program to launch programs for debugging.
1721 set multiple-symbols (all|ask|cancel)
1722 show multiple-symbols
1723 The value of this variable can be changed to adjust the debugger behavior
1724 when an expression or a breakpoint location contains an ambiguous symbol
1725 name (an overloaded function name, for instance).
1727 set breakpoint always-inserted
1728 show breakpoint always-inserted
1729 Keep breakpoints always inserted in the target, as opposed to inserting
1730 them when resuming the target, and removing them when the target stops.
1731 This option can improve debugger performance on slow remote targets.
1733 set arm fallback-mode (arm|thumb|auto)
1734 show arm fallback-mode
1735 set arm force-mode (arm|thumb|auto)
1737 These commands control how ARM GDB determines whether instructions
1738 are ARM or Thumb. The default for both settings is auto, which uses
1739 the current CPSR value for instructions without symbols; previous
1740 versions of GDB behaved as if "set arm fallback-mode arm".
1742 set disable-randomization
1743 show disable-randomization
1744 Standalone programs run with the virtual address space randomization enabled
1745 by default on some platforms. This option keeps the addresses stable across
1746 multiple debugging sessions.
1750 Control whether other threads are stopped or not when some thread hits
1755 Requests that asynchronous execution is enabled in the target, if available.
1756 In this case, it's possible to resume target in the background, and interact
1757 with GDB while the target is running. "show target-async" displays the
1758 current state of asynchronous execution of the target.
1760 set target-wide-charset
1761 show target-wide-charset
1762 The target-wide-charset is the name of the character set that GDB
1763 uses when printing characters whose type is wchar_t.
1765 set tcp auto-retry (on|off)
1767 set tcp connect-timeout
1768 show tcp connect-timeout
1769 These commands allow GDB to retry failed TCP connections to a remote stub
1770 with a specified timeout period; this is useful if the stub is launched
1771 in parallel with GDB but may not be ready to accept connections immediately.
1773 set libthread-db-search-path
1774 show libthread-db-search-path
1775 Control list of directories which GDB will search for appropriate
1778 set schedule-multiple (on|off)
1779 show schedule-multiple
1780 Allow GDB to resume all threads of all processes or only threads of
1781 the current process.
1785 Use more aggressive caching for accesses to the stack. This improves
1786 performance of remote debugging (particularly backtraces) without
1787 affecting correctness.
1789 set interactive-mode (on|off|auto)
1790 show interactive-mode
1791 Control whether GDB runs in interactive mode (on) or not (off).
1792 When in interactive mode, GDB waits for the user to answer all
1793 queries. Otherwise, GDB does not wait and assumes the default
1794 answer. When set to auto (the default), GDB determines which
1795 mode to use based on the stdin settings.
1800 For program forks, this is replaced by the new more generic `info
1801 inferiors' command. To list checkpoints, you can still use the
1802 `info checkpoints' command, which was an alias for the `info forks'
1806 Replaced by the new `inferior' command. To switch between
1807 checkpoints, you can still use the `restart' command, which was an
1808 alias for the `fork' command.
1811 This is removed, since some targets don't have a notion of
1812 processes. To switch between processes, you can still use the
1813 `inferior' command using GDB's own inferior number.
1816 For program forks, this is replaced by the new more generic `kill
1817 inferior' command. To delete a checkpoint, you can still use the
1818 `delete checkpoint' command, which was an alias for the `delete
1822 For program forks, this is replaced by the new more generic `detach
1823 inferior' command. To detach a checkpoint, you can still use the
1824 `detach checkpoint' command, which was an alias for the `detach
1827 * New native configurations
1829 x86/x86_64 Darwin i[34567]86-*-darwin*
1831 x86_64 MinGW x86_64-*-mingw*
1835 Lattice Mico32 lm32-*
1836 x86 DICOS i[34567]86-*-dicos*
1837 x86_64 DICOS x86_64-*-dicos*
1840 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1841 (mingw32ce) debugging.
1847 These commands were actually not implemented on any target.
1849 *** Changes in GDB 6.8
1851 * New native configurations
1853 NetBSD/hppa hppa*-*netbsd*
1854 Xtensa GNU/Linux xtensa*-*-linux*
1858 NetBSD/hppa hppa*-*-netbsd*
1859 Xtensa GNU/Lunux xtensa*-*-linux*
1861 * Change in command line behavior -- corefiles vs. process ids.
1863 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1864 attaching to process NUMBER fails, GDB no longer attempts to open a
1865 core file named NUMBER. Attaching to a program using the -c option
1866 is no longer supported. Instead, use the '-p' or '--pid' options.
1868 * GDB can now be built as a native debugger for debugging Windows x86
1869 (mingw32) Portable Executable (PE) programs.
1871 * Pending breakpoints no longer change their number when their address
1874 * GDB now supports breakpoints with multiple locations,
1875 including breakpoints on C++ constructors, inside C++ templates,
1876 and in inlined functions.
1878 * GDB's ability to debug optimized code has been improved. GDB more
1879 accurately identifies function bodies and lexical blocks that occupy
1880 more than one contiguous range of addresses.
1882 * Target descriptions can now describe registers for PowerPC.
1884 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1885 registers on PowerPC targets.
1887 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1888 targets even when the libthread_db library is not available.
1890 * The GDB remote stub, gdbserver, now supports the new file transfer
1891 commands (remote put, remote get, and remote delete).
1893 * The GDB remote stub, gdbserver, now supports run and attach in
1894 extended-remote mode.
1896 * hppa*64*-*-hpux11* target broken
1897 The debugger is unable to start a program and fails with the following
1898 error: "Error trying to get information about dynamic linker".
1899 The gdb-6.7 release is also affected.
1901 * GDB now supports the --enable-targets= configure option to allow
1902 building a single GDB executable that supports multiple remote
1903 target architectures.
1905 * GDB now supports debugging C and C++ programs which use the
1906 Decimal Floating Point extension. In addition, the PowerPC target
1907 now has a set of pseudo-registers to inspect decimal float values
1908 stored in two consecutive float registers.
1910 * The -break-insert MI command can optionally create pending
1913 * Improved support for debugging Ada
1914 Many improvements to the Ada language support have been made. These
1916 - Better support for Ada2005 interface types
1917 - Improved handling of arrays and slices in general
1918 - Better support for Taft-amendment types
1919 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1921 - Improved command completion in Ada
1924 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1929 set print frame-arguments (all|scalars|none)
1930 show print frame-arguments
1931 The value of this variable can be changed to control which argument
1932 values should be printed by the debugger when displaying a frame.
1937 Transfer files to and from a remote target, and delete remote files.
1944 Transfer files to and from a remote target, and delete remote files.
1946 * New remote packets
1953 Open, close, read, write, and delete files on the remote system.
1956 Attach to an existing process on the remote system, in extended-remote
1960 Run a new process on the remote system, in extended-remote mode.
1962 *** Changes in GDB 6.7
1964 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1965 bfd, libiberty and opcodes, as revealed by static analysis donated by
1966 Coverity, Inc. (http://scan.coverity.com).
1968 * When looking up multiply-defined global symbols, GDB will now prefer the
1969 symbol definition in the current shared library if it was built using the
1970 -Bsymbolic linker option.
1972 * When the Text User Interface (TUI) is not configured, GDB will now
1973 recognize the -tui command-line option and print a message that the TUI
1976 * The GDB remote stub, gdbserver, now has lower overhead for high
1977 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1979 * GDB for MIPS targets now autodetects whether a remote target provides
1980 32-bit or 64-bit register values.
1982 * Support for C++ member pointers has been improved.
1984 * GDB now understands XML target descriptions, which specify the
1985 target's overall architecture. GDB can read a description from
1986 a local file or over the remote serial protocol.
1988 * Vectors of single-byte data use a new integer type which is not
1989 automatically displayed as character or string data.
1991 * The /s format now works with the print command. It displays
1992 arrays of single-byte integers and pointers to single-byte integers
1995 * Target descriptions can now describe target-specific registers,
1996 for architectures which have implemented the support (currently
1997 only ARM, M68K, and MIPS).
1999 * GDB and the GDB remote stub, gdbserver, now support the XScale
2002 * The GDB remote stub, gdbserver, has been updated to support
2003 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
2004 has been rewritten to use the standard GDB remote protocol.
2006 * GDB can now step into C++ functions which are called through thunks.
2008 * GDB for the Cell/B.E. SPU now supports overlay debugging.
2010 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2011 layout. It also supports a TextSeg= and DataSeg= response when only
2012 segment base addresses (rather than offsets) are available.
2014 * The /i format now outputs any trailing branch delay slot instructions
2015 immediately following the last instruction within the count specified.
2017 * The GDB remote protocol "T" stop reply packet now supports a
2018 "library" response. Combined with the new "qXfer:libraries:read"
2019 packet, this response allows GDB to debug shared libraries on targets
2020 where the operating system manages the list of loaded libraries (e.g.
2021 Windows and SymbianOS).
2023 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2024 (DLLs) on Windows and Windows CE targets.
2026 * GDB now supports a faster verification that a .debug file matches its binary
2027 according to its build-id signature, if the signature is present.
2033 Enable or disable hardware flow control (RTS/CTS) on the serial port
2034 when debugging using remote targets.
2036 set mem inaccessible-by-default
2037 show mem inaccessible-by-default
2038 If the target supplies a memory map, for instance via the remote
2039 protocol's "qXfer:memory-map:read" packet, setting this variable
2040 prevents GDB from accessing memory outside the memory map. This
2041 is useful for targets with memory mapped registers or which react
2042 badly to accesses of unmapped address space.
2044 set breakpoint auto-hw
2045 show breakpoint auto-hw
2046 If the target supplies a memory map, for instance via the remote
2047 protocol's "qXfer:memory-map:read" packet, setting this variable
2048 lets GDB use hardware breakpoints automatically for memory regions
2049 where it can not use software breakpoints. This covers both the
2050 "break" command and internal breakpoints used for other commands
2051 including "next" and "finish".
2054 catch exception unhandled
2055 Stop the program execution when Ada exceptions are raised.
2058 Stop the program execution when an Ada assertion failed.
2062 Set an alternate system root for target files. This is a more
2063 general version of "set solib-absolute-prefix", which is now
2064 an alias to "set sysroot".
2067 Provide extended SPU facility status information. This set of
2068 commands is available only when debugging the Cell/B.E. SPU
2071 * New native configurations
2073 OpenBSD/sh sh*-*openbsd*
2076 unset tdesc filename
2078 Use the specified local file as an XML target description, and do
2079 not query the target for its built-in description.
2083 OpenBSD/sh sh*-*-openbsd*
2084 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2085 Toshiba Media Processor mep-elf
2087 * New remote packets
2090 Ignore the specified signals; pass them directly to the debugged program
2091 without stopping other threads or reporting them to GDB.
2093 qXfer:features:read:
2094 Read an XML target description from the target, which describes its
2099 Read or write contents of an spufs file on the target system. These
2100 packets are available only on the Cell/B.E. SPU architecture.
2102 qXfer:libraries:read:
2103 Report the loaded shared libraries. Combined with new "T" packet
2104 response, this packet allows GDB to debug shared libraries on
2105 targets where the operating system manages the list of loaded
2106 libraries (e.g. Windows and SymbianOS).
2110 Support for these obsolete configurations has been removed.
2118 i[34567]86-*-lynxos*
2119 i[34567]86-*-netware*
2120 i[34567]86-*-sco3.2v5*
2121 i[34567]86-*-sco3.2v4*
2123 i[34567]86-*-sysv4.2*
2126 i[34567]86-*-unixware2*
2127 i[34567]86-*-unixware*
2136 * Other removed features
2143 Various m68k-only ROM monitors.
2150 Various Renesas ROM monitors and debugging interfaces for SH and
2155 Support for a Macraigor serial interface to on-chip debugging.
2156 GDB does not directly support the newer parallel or USB
2161 A debug information format. The predecessor to DWARF 2 and
2162 DWARF 3, which are still supported.
2164 Support for the HP aCC compiler on HP-UX/PA-RISC
2166 SOM-encapsulated symbolic debugging information, automatic
2167 invocation of pxdb, and the aCC custom C++ ABI. This does not
2168 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2169 with aCC can still be debugged on an assembly level.
2171 MIPS ".pdr" sections
2173 A MIPS-specific format used to describe stack frame layout
2174 in debugging information.
2178 GDB could work with an older version of Guile to debug
2179 the interpreter and Scheme programs running in it.
2181 set mips stack-arg-size
2182 set mips saved-gpreg-size
2184 Use "set mips abi" to control parameter passing for MIPS.
2186 *** Changes in GDB 6.6
2191 Cell Broadband Engine SPU spu-elf
2193 * GDB can now be configured as a cross-debugger targeting native Windows
2194 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2195 running on a Windows system over TCP/IP to debug Windows programs.
2197 * The GDB remote stub, gdbserver, has been updated to support Windows and
2198 Cygwin debugging. Both single-threaded and multi-threaded programs are
2201 * The "set trust-readonly-sections" command works again. This command was
2202 broken in GDB 6.3, 6.4, and 6.5.
2204 * The "load" command now supports writing to flash memory, if the remote
2205 stub provides the required support.
2207 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2208 longer requires symbolic debug information (e.g. DWARF-2).
2213 unset substitute-path
2214 show substitute-path
2215 Manage a list of substitution rules that GDB uses to rewrite the name
2216 of the directories where the sources are located. This can be useful
2217 for instance when the sources were moved to a different location
2218 between compilation and debugging.
2222 Print each CLI command as it is executed. Each command is prefixed with
2223 a number of `+' symbols representing the nesting depth.
2224 The source command now has a `-v' option to enable the same feature.
2228 The ARM Demon monitor support (RDP protocol, "target rdp").
2230 Kernel Object Display, an embedded debugging feature which only worked with
2231 an obsolete version of Cisco IOS.
2233 The 'set download-write-size' and 'show download-write-size' commands.
2235 * New remote packets
2238 Tell a stub about GDB client features, and request remote target features.
2239 The first feature implemented is PacketSize, which allows the target to
2240 specify the size of packets it can handle - to minimize the number of
2241 packets required and improve performance when connected to a remote
2245 Fetch an OS auxilliary vector from the remote stub. This packet is a
2246 more efficient replacement for qPart:auxv:read.
2248 qXfer:memory-map:read:
2249 Fetch a memory map from the remote stub, including information about
2250 RAM, ROM, and flash memory devices.
2255 Erase and program a flash memory device.
2257 * Removed remote packets
2260 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2261 used it, and only gdbserver implemented it.
2263 *** Changes in GDB 6.5
2267 Renesas M32C/M16C m32c-elf
2269 Morpho Technologies ms1 ms1-elf
2273 init-if-undefined Initialize a convenience variable, but
2274 only if it doesn't already have a value.
2276 The following commands are presently only implemented for native GNU/Linux:
2278 checkpoint Save a snapshot of the program state.
2280 restart <n> Return the program state to a
2281 previously saved state.
2283 info checkpoints List currently saved checkpoints.
2285 delete-checkpoint <n> Delete a previously saved checkpoint.
2287 set|show detach-on-fork Tell gdb whether to detach from a newly
2288 forked process, or to keep debugging it.
2290 info forks List forks of the user program that
2291 are available to be debugged.
2293 fork <n> Switch to debugging one of several
2294 forks of the user program that are
2295 available to be debugged.
2297 delete-fork <n> Delete a fork from the list of forks
2298 that are available to be debugged (and
2299 kill the forked process).
2301 detach-fork <n> Delete a fork from the list of forks
2302 that are available to be debugged (and
2303 allow the process to continue).
2307 Morpho Technologies ms2 ms1-elf
2309 * Improved Windows host support
2311 GDB now builds as a cross debugger hosted on i686-mingw32, including
2312 native console support, and remote communications using either
2313 network sockets or serial ports.
2315 * Improved Modula-2 language support
2317 GDB can now print most types in the Modula-2 syntax. This includes:
2318 basic types, set types, record types, enumerated types, range types,
2319 pointer types and ARRAY types. Procedure var parameters are correctly
2320 printed and hexadecimal addresses and character constants are also
2321 written in the Modula-2 syntax. Best results can be obtained by using
2322 GNU Modula-2 together with the -gdwarf-2 command line option.
2326 The ARM rdi-share module.
2328 The Netware NLM debug server.
2330 *** Changes in GDB 6.4
2332 * New native configurations
2334 OpenBSD/arm arm*-*-openbsd*
2335 OpenBSD/mips64 mips64-*-openbsd*
2339 Morpho Technologies ms1 ms1-elf
2341 * New command line options
2343 --batch-silent As for --batch, but totally silent.
2344 --return-child-result The debugger will exist with the same value
2345 the child (debugged) program exited with.
2346 --eval-command COMMAND, -ex COMMAND
2347 Execute a single GDB CLI command. This may be
2348 specified multiple times and in conjunction
2349 with the --command (-x) option.
2351 * Deprecated commands removed
2353 The following commands, that were deprecated in 2000, have been
2357 set|show arm disassembly-flavor set|show arm disassembler
2358 othernames set arm disassembler
2359 set|show remotedebug set|show debug remote
2360 set|show archdebug set|show debug arch
2361 set|show eventdebug set|show debug event
2364 * New BSD user-level threads support
2366 It is now possible to debug programs using the user-level threads
2367 library on OpenBSD and FreeBSD. Currently supported (target)
2370 FreeBSD/amd64 x86_64-*-freebsd*
2371 FreeBSD/i386 i386-*-freebsd*
2372 OpenBSD/i386 i386-*-openbsd*
2374 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2375 are not yet supported.
2377 * New support for Matsushita MN10300 w/sim added
2378 (Work in progress). mn10300-elf.
2380 * REMOVED configurations and files
2382 VxWorks and the XDR protocol *-*-vxworks
2383 Motorola MCORE mcore-*-*
2384 National Semiconductor NS32000 ns32k-*-*
2386 * New "set print array-indexes" command
2388 After turning this setting "on", GDB prints the index of each element
2389 when displaying arrays. The default is "off" to preserve the previous
2392 * VAX floating point support
2394 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2396 * User-defined command support
2398 In addition to using $arg0..$arg9 for argument passing, it is now possible
2399 to use $argc to determine now many arguments have been passed. See the
2400 section on user-defined commands in the user manual for more information.
2402 *** Changes in GDB 6.3:
2404 * New command line option
2406 GDB now accepts -l followed by a number to set the timeout for remote
2409 * GDB works with GCC -feliminate-dwarf2-dups
2411 GDB now supports a more compact representation of DWARF-2 debug
2412 information using DW_FORM_ref_addr references. These are produced
2413 by GCC with the option -feliminate-dwarf2-dups and also by some
2414 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2415 to use -feliminate-dwarf2-dups.
2417 * Internationalization
2419 When supported by the host system, GDB will be built with
2420 internationalization (libintl). The task of marking up the sources is
2421 continued, we're looking forward to our first translation.
2425 Initial support for debugging programs compiled with the GNAT
2426 implementation of the Ada programming language has been integrated
2427 into GDB. In this release, support is limited to expression evaluation.
2429 * New native configurations
2431 GNU/Linux/m32r m32r-*-linux-gnu
2435 GDB's remote protocol now includes support for the 'p' packet. This
2436 packet is used to fetch individual registers from a remote inferior.
2438 * END-OF-LIFE registers[] compatibility module
2440 GDB's internal register infrastructure has been completely rewritten.
2441 The new infrastructure making possible the implementation of key new
2442 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2445 GDB 6.3 will be the last release to include the the registers[]
2446 compatibility module that allowed out-of-date configurations to
2447 continue to work. This change directly impacts the following
2457 powerpc bdm protocol
2459 Unless there is activity to revive these configurations, they will be
2460 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2462 * OBSOLETE configurations and files
2464 Configurations that have been declared obsolete in this release have
2465 been commented out. Unless there is activity to revive these
2466 configurations, the next release of GDB will have their sources
2467 permanently REMOVED.
2476 *** Changes in GDB 6.2.1:
2478 * MIPS `break main; run' gave an heuristic-fence-post warning
2480 When attempting to run even a simple program, a warning about
2481 heuristic-fence-post being hit would be reported. This problem has
2484 * MIPS IRIX 'long double' crashed GDB
2486 When examining a long double variable, GDB would get a segmentation
2487 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2488 IRIX long double values).
2492 A bug in the VAX stack code was causing problems with the "next"
2493 command. This problem has been fixed.
2495 *** Changes in GDB 6.2:
2497 * Fix for ``many threads''
2499 On GNU/Linux systems that use the NPTL threads library, a program
2500 rapidly creating and deleting threads would confuse GDB leading to the
2503 ptrace: No such process.
2504 thread_db_get_info: cannot get thread info: generic error
2506 This problem has been fixed.
2508 * "-async" and "-noasync" options removed.
2510 Support for the broken "-noasync" option has been removed (it caused
2513 * New ``start'' command.
2515 This command runs the program until the begining of the main procedure.
2517 * New BSD Kernel Data Access Library (libkvm) interface
2519 Using ``target kvm'' it is now possible to debug kernel core dumps and
2520 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2521 platforms. Currently supported (native-only) configurations are:
2523 FreeBSD/amd64 x86_64-*-freebsd*
2524 FreeBSD/i386 i?86-*-freebsd*
2525 NetBSD/i386 i?86-*-netbsd*
2526 NetBSD/m68k m68*-*-netbsd*
2527 NetBSD/sparc sparc-*-netbsd*
2528 OpenBSD/amd64 x86_64-*-openbsd*
2529 OpenBSD/i386 i?86-*-openbsd*
2530 OpenBSD/m68k m68*-openbsd*
2531 OpenBSD/sparc sparc-*-openbsd*
2533 * Signal trampoline code overhauled
2535 Many generic problems with GDB's signal handling code have been fixed.
2536 These include: backtraces through non-contiguous stacks; recognition
2537 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2538 call; backtrace through a signal trampoline; step into and out of
2539 signal handlers; and single-stepping in the signal trampoline.
2541 Please note that kernel bugs are a limiting factor here. These
2542 features have been shown to work on an s390 GNU/Linux system that
2543 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2545 * Cygwin support for DWARF 2 added.
2547 * New native configurations
2549 GNU/Linux/hppa hppa*-*-linux*
2550 OpenBSD/hppa hppa*-*-openbsd*
2551 OpenBSD/m68k m68*-*-openbsd*
2552 OpenBSD/m88k m88*-*-openbsd*
2553 OpenBSD/powerpc powerpc-*-openbsd*
2554 NetBSD/vax vax-*-netbsd*
2555 OpenBSD/vax vax-*-openbsd*
2557 * END-OF-LIFE frame compatibility module
2559 GDB's internal frame infrastructure has been completely rewritten.
2560 The new infrastructure making it possible to support key new features
2561 including DWARF 2 Call Frame Information. To aid in the task of
2562 migrating old configurations to this new infrastructure, a
2563 compatibility module, that allowed old configurations to continue to
2564 work, was also included.
2566 GDB 6.2 will be the last release to include this frame compatibility
2567 module. This change directly impacts the following configurations:
2577 Unless there is activity to revive these configurations, they will be
2578 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2580 * REMOVED configurations and files
2582 Sun 3, running SunOS 3 m68*-*-sunos3*
2583 Sun 3, running SunOS 4 m68*-*-sunos4*
2584 Sun 2, running SunOS 3 m68000-*-sunos3*
2585 Sun 2, running SunOS 4 m68000-*-sunos4*
2586 Motorola 680x0 running LynxOS m68*-*-lynxos*
2587 AT&T 3b1/Unix pc m68*-att-*
2588 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2589 decstation mips-dec-* mips-little-*
2590 riscos mips-*-riscos* mips-*-sysv*
2591 sonymips mips-sony-*
2592 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2594 *** Changes in GDB 6.1.1:
2596 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2598 The TUI (Text-mode User Interface) is now built as part of a default
2599 GDB configuration. It is enabled by either selecting the TUI with the
2600 command line option "-i=tui" or by running the separate "gdbtui"
2601 program. For more information on the TUI, see the manual "Debugging
2604 * Pending breakpoint support (also included in GDB 6.1)
2606 Support has been added to allow you to specify breakpoints in shared
2607 libraries that have not yet been loaded. If a breakpoint location
2608 cannot be found, and the "breakpoint pending" option is set to auto,
2609 GDB queries you if you wish to make the breakpoint pending on a future
2610 shared-library load. If and when GDB resolves the breakpoint symbol,
2611 the pending breakpoint is removed as one or more regular breakpoints
2614 Pending breakpoints are very useful for GCJ Java debugging.
2616 * Fixed ISO-C build problems
2618 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2619 non ISO-C code that stopped them being built using a more strict ISO-C
2620 compiler (e.g., IBM's C compiler).
2622 * Fixed build problem on IRIX 5
2624 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2625 wasn't able to compile compile on an IRIX 5 system.
2627 * Added execute permission to gdb/gdbserver/configure
2629 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2630 permission. This bug would cause configure to fail on a number of
2631 systems (Solaris, IRIX). Ref: server/519.
2633 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2635 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2636 has been updated to use constant array sizes.
2638 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2640 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2641 its generated DWARF Call Frame Info. This encoding was causing GDB to
2642 panic, that panic has been fixed. Ref: gdb/1628.
2644 * Fixed a problem when examining parameters in shared library code.
2646 When examining parameters in optimized shared library code generated
2647 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2648 not available''. GDB now correctly displays the variable's value.
2650 *** Changes in GDB 6.1:
2652 * Removed --with-mmalloc
2654 Support for the mmalloc memory manager has been removed, as it
2655 conflicted with the internal gdb byte cache.
2657 * Changes in AMD64 configurations
2659 The AMD64 target now includes the %cs and %ss registers. As a result
2660 the AMD64 remote protocol has changed; this affects the floating-point
2661 and SSE registers. If you rely on those registers for your debugging,
2662 you should upgrade gdbserver on the remote side.
2664 * Revised SPARC target
2666 The SPARC target has been completely revised, incorporating the
2667 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2668 support for LynxOS and SunOS 4 has been dropped. Calling functions
2669 from within GDB on operating systems with a non-executable stack
2670 (Solaris, OpenBSD) now works.
2674 GDB has a new C++ demangler which does a better job on the mangled
2675 names generated by current versions of g++. It also runs faster, so
2676 with this and other changes gdb should now start faster on large C++
2679 * DWARF 2 Location Expressions
2681 GDB support for location expressions has been extended to support function
2682 arguments and frame bases. Older versions of GDB could crash when they
2685 * C++ nested types and namespaces
2687 GDB's support for nested types and namespaces in C++ has been
2688 improved, especially if you use the DWARF 2 debugging format. (This
2689 is the default for recent versions of GCC on most platforms.)
2690 Specifically, if you have a class "Inner" defined within a class or
2691 namespace "Outer", then GDB realizes that the class's name is
2692 "Outer::Inner", not simply "Inner". This should greatly reduce the
2693 frequency of complaints about not finding RTTI symbols. In addition,
2694 if you are stopped at inside of a function defined within a namespace,
2695 GDB modifies its name lookup accordingly.
2697 * New native configurations
2699 NetBSD/amd64 x86_64-*-netbsd*
2700 OpenBSD/amd64 x86_64-*-openbsd*
2701 OpenBSD/alpha alpha*-*-openbsd*
2702 OpenBSD/sparc sparc-*-openbsd*
2703 OpenBSD/sparc64 sparc64-*-openbsd*
2705 * New debugging protocols
2707 M32R with SDI protocol m32r-*-elf*
2709 * "set prompt-escape-char" command deleted.
2711 The command "set prompt-escape-char" has been deleted. This command,
2712 and its very obscure effet on GDB's prompt, was never documented,
2713 tested, nor mentioned in the NEWS file.
2715 * OBSOLETE configurations and files
2717 Configurations that have been declared obsolete in this release have
2718 been commented out. Unless there is activity to revive these
2719 configurations, the next release of GDB will have their sources
2720 permanently REMOVED.
2722 Sun 3, running SunOS 3 m68*-*-sunos3*
2723 Sun 3, running SunOS 4 m68*-*-sunos4*
2724 Sun 2, running SunOS 3 m68000-*-sunos3*
2725 Sun 2, running SunOS 4 m68000-*-sunos4*
2726 Motorola 680x0 running LynxOS m68*-*-lynxos*
2727 AT&T 3b1/Unix pc m68*-att-*
2728 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2729 decstation mips-dec-* mips-little-*
2730 riscos mips-*-riscos* mips-*-sysv*
2731 sonymips mips-sony-*
2732 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2734 * REMOVED configurations and files
2736 SGI Irix-4.x mips-sgi-irix4 or iris4
2737 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2738 Z8000 simulator z8k-zilog-none or z8ksim
2739 Matsushita MN10200 w/simulator mn10200-*-*
2740 H8/500 simulator h8500-hitachi-hms or h8500hms
2741 HP/PA running BSD hppa*-*-bsd*
2742 HP/PA running OSF/1 hppa*-*-osf*
2743 HP/PA Pro target hppa*-*-pro*
2744 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2745 386BSD i[3456]86-*-bsd*
2746 Sequent family i[3456]86-sequent-sysv4*
2747 i[3456]86-sequent-sysv*
2748 i[3456]86-sequent-bsd*
2749 SPARC running LynxOS sparc-*-lynxos*
2750 SPARC running SunOS 4 sparc-*-sunos4*
2751 Tsqware Sparclet sparclet-*-*
2752 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2754 *** Changes in GDB 6.0:
2758 Support for debugging the Objective-C programming language has been
2759 integrated into GDB.
2761 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2763 DWARF 2's Call Frame Information makes available compiler generated
2764 information that more exactly describes the program's run-time stack.
2765 By using this information, GDB is able to provide more robust stack
2768 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2769 have been updated to use a new backtrace mechanism which includes
2770 DWARF 2 CFI support.
2774 GDB's remote protocol has been extended to include support for hosted
2775 file I/O (where the remote target uses GDB's file system). See GDB's
2776 remote protocol documentation for details.
2778 * All targets using the new architecture framework.
2780 All of GDB's targets have been updated to use the new internal
2781 architecture framework. The way is now open for future GDB releases
2782 to include cross-architecture native debugging support (i386 on amd64,
2785 * GNU/Linux's Thread Local Storage (TLS)
2787 GDB now includes support for for the GNU/Linux implementation of
2788 per-thread variables.
2790 * GNU/Linux's Native POSIX Thread Library (NPTL)
2792 GDB's thread code has been updated to work with either the new
2793 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2795 * Separate debug info.
2797 GDB, in conjunction with BINUTILS, now supports a mechanism for
2798 automatically loading debug information from a separate file. Instead
2799 of shipping full debug and non-debug versions of system libraries,
2800 system integrators can now instead ship just the stripped libraries
2801 and optional debug files.
2803 * DWARF 2 Location Expressions
2805 DWARF 2 Location Expressions allow the compiler to more completely
2806 describe the location of variables (even in optimized code) to the
2809 GDB now includes preliminary support for location expressions (support
2810 for DW_OP_piece is still missing).
2814 A number of long standing bugs that caused GDB to die while starting a
2815 Java application have been fixed. GDB's Java support is now
2816 considered "useable".
2818 * GNU/Linux support for fork, vfork, and exec.
2820 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2821 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2824 * GDB supports logging output to a file
2826 There are two new commands, "set logging" and "show logging", which can be
2827 used to capture GDB's output to a file.
2829 * The meaning of "detach" has changed for gdbserver
2831 The "detach" command will now resume the application, as documented. To
2832 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2835 * d10v, m68hc11 `regs' command deprecated
2837 The `info registers' command has been updated so that it displays the
2838 registers using a format identical to the old `regs' command.
2842 A new command, "maint set profile on/off", has been added. This command can
2843 be used to enable or disable profiling while running GDB, to profile a
2844 session or a set of commands. In addition there is a new configure switch,
2845 "--enable-profiling", which will cause GDB to be compiled with profiling
2846 data, for more informative profiling results.
2848 * Default MI syntax changed to "mi2".
2850 The default MI (machine interface) syntax, enabled by the command line
2851 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2852 "mi1", can be enabled by specifying the option "-i=mi1".
2854 Support for the original "mi0" syntax (included in GDB 5.0) has been
2857 Fix for gdb/192: removed extraneous space when displaying frame level.
2858 Fix for gdb/672: update changelist is now output in mi list format.
2859 Fix for gdb/702: a -var-assign that updates the value now shows up
2860 in a subsequent -var-update.
2862 * New native configurations.
2864 FreeBSD/amd64 x86_64-*-freebsd*
2866 * Multi-arched targets.
2868 HP/PA HPUX11 hppa*-*-hpux*
2869 Renesas M32R/D w/simulator m32r-*-elf*
2871 * OBSOLETE configurations and files
2873 Configurations that have been declared obsolete in this release have
2874 been commented out. Unless there is activity to revive these
2875 configurations, the next release of GDB will have their sources
2876 permanently REMOVED.
2878 Z8000 simulator z8k-zilog-none or z8ksim
2879 Matsushita MN10200 w/simulator mn10200-*-*
2880 H8/500 simulator h8500-hitachi-hms or h8500hms
2881 HP/PA running BSD hppa*-*-bsd*
2882 HP/PA running OSF/1 hppa*-*-osf*
2883 HP/PA Pro target hppa*-*-pro*
2884 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2885 Sequent family i[3456]86-sequent-sysv4*
2886 i[3456]86-sequent-sysv*
2887 i[3456]86-sequent-bsd*
2888 Tsqware Sparclet sparclet-*-*
2889 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2891 * REMOVED configurations and files
2894 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2895 IBM AIX PS/2 i[3456]86-*-aix
2896 i386 running Mach 3.0 i[3456]86-*-mach3*
2897 i386 running Mach i[3456]86-*-mach*
2898 i386 running OSF/1 i[3456]86-*osf1mk*
2899 HP/Apollo 68k Family m68*-apollo*-sysv*,
2901 m68*-hp-bsd*, m68*-hp-hpux*
2902 Argonaut Risc Chip (ARC) arc-*-*
2903 Mitsubishi D30V d30v-*-*
2904 Fujitsu FR30 fr30-*-elf*
2905 OS/9000 i[34]86-*-os9k
2906 I960 with MON960 i960-*-coff
2908 * MIPS $fp behavior changed
2910 The convenience variable $fp, for the MIPS, now consistently returns
2911 the address of the current frame's base. Previously, depending on the
2912 context, $fp could refer to either $sp or the current frame's base
2913 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2914 The GNU Source-Level Debugger''.
2916 *** Changes in GDB 5.3:
2918 * GNU/Linux shared library multi-threaded performance improved.
2920 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2921 `/proc', in preference to `ptrace' for memory reads. This may result
2922 in an improvement in the start-up time of multi-threaded, shared
2923 library applications when run under GDB. One GDB user writes: ``loads
2924 shared libs like mad''.
2926 * ``gdbserver'' now supports multi-threaded applications on some targets
2928 Support for debugging multi-threaded applications which use
2929 the GNU/Linux LinuxThreads package has been added for
2930 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2931 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2933 * GDB now supports C/C++ preprocessor macros.
2935 GDB now expands preprocessor macro invocations in C/C++ expressions,
2936 and provides various commands for showing macro definitions and how
2939 The new command `macro expand EXPRESSION' expands any macro
2940 invocations in expression, and shows the result.
2942 The new command `show macro MACRO-NAME' shows the definition of the
2943 macro named MACRO-NAME, and where it was defined.
2945 Most compilers don't include information about macros in the debugging
2946 information by default. In GCC 3.1, for example, you need to compile
2947 your program with the options `-gdwarf-2 -g3'. If the macro
2948 information is present in the executable, GDB will read it.
2950 * Multi-arched targets.
2952 DEC Alpha (partial) alpha*-*-*
2953 DEC VAX (partial) vax-*-*
2955 National Semiconductor NS32000 (partial) ns32k-*-*
2956 Motorola 68000 (partial) m68k-*-*
2957 Motorola MCORE mcore-*-*
2961 Fujitsu FRV architecture added by Red Hat frv*-*-*
2964 * New native configurations
2966 Alpha NetBSD alpha*-*-netbsd*
2967 SH NetBSD sh*-*-netbsdelf*
2968 MIPS NetBSD mips*-*-netbsd*
2969 UltraSPARC NetBSD sparc64-*-netbsd*
2971 * OBSOLETE configurations and files
2973 Configurations that have been declared obsolete in this release have
2974 been commented out. Unless there is activity to revive these
2975 configurations, the next release of GDB will have their sources
2976 permanently REMOVED.
2978 Mitsubishi D30V d30v-*-*
2979 OS/9000 i[34]86-*-os9k
2980 IBM AIX PS/2 i[3456]86-*-aix
2981 Fujitsu FR30 fr30-*-elf*
2982 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2983 Argonaut Risc Chip (ARC) arc-*-*
2984 i386 running Mach 3.0 i[3456]86-*-mach3*
2985 i386 running Mach i[3456]86-*-mach*
2986 i386 running OSF/1 i[3456]86-*osf1mk*
2987 HP/Apollo 68k Family m68*-apollo*-sysv*,
2989 m68*-hp-bsd*, m68*-hp-hpux*
2990 I960 with MON960 i960-*-coff
2992 * OBSOLETE languages
2994 CHILL, a Pascal like language used by telecommunications companies.
2996 * REMOVED configurations and files
2998 AMD 29k family via UDI a29k-amd-udi, udi29k
2999 A29K VxWorks a29k-*-vxworks
3000 AMD 29000 embedded, using EBMON a29k-none-none
3001 AMD 29000 embedded with COFF a29k-none-coff
3002 AMD 29000 embedded with a.out a29k-none-aout
3004 testsuite/gdb.hp/gdb.threads-hp/ directory
3006 * New command "set max-user-call-depth <nnn>"
3008 This command allows the user to limit the call depth of user-defined
3009 commands. The default is 1024.
3011 * Changes in FreeBSD/i386 native debugging.
3013 Support for the "generate-core-file" has been added.
3015 * New commands "dump", "append", and "restore".
3017 These commands allow data to be copied from target memory
3018 to a bfd-format or binary file (dump and append), and back
3019 from a file into memory (restore).
3021 * Improved "next/step" support on multi-processor Alpha Tru64.
3023 The previous single-step mechanism could cause unpredictable problems,
3024 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3025 of a software single-step mechanism prevents this.
3027 *** Changes in GDB 5.2.1:
3035 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3036 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3037 Fix, by Joel Brobecker imported from mainline.
3039 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3040 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3041 Fix, by Fred Fish, imported from mainline.
3043 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3044 Surprisingly enough, it works now.
3045 By Michal Ludvig, imported from mainline.
3047 i386 hardware watchpoint support:
3048 avoid misses on second run for some targets.
3049 By Pierre Muller, imported from mainline.
3051 *** Changes in GDB 5.2:
3053 * New command "set trust-readonly-sections on[off]".
3055 This command is a hint that tells gdb that read-only sections
3056 really are read-only (ie. that their contents will not change).
3057 In this mode, gdb will go to the object file rather than the
3058 target to read memory from read-only sections (such as ".text").
3059 This can be a significant performance improvement on some
3060 (notably embedded) targets.
3062 * New command "generate-core-file" (or "gcore").
3064 This new gdb command allows the user to drop a core file of the child
3065 process state at any time. So far it's been implemented only for
3066 GNU/Linux and Solaris, but should be relatively easily ported to other
3067 hosts. Argument is core file name (defaults to core.<pid>).
3069 * New command line option
3071 GDB now accepts --pid or -p followed by a process id.
3073 * Change in command line behavior -- corefiles vs. process ids.
3075 There is a subtle behavior in the way in which GDB handles
3076 command line arguments. The first non-flag argument is always
3077 a program to debug, but the second non-flag argument may either
3078 be a corefile or a process id. Previously, GDB would attempt to
3079 open the second argument as a corefile, and if that failed, would
3080 issue a superfluous error message and then attempt to attach it as
3081 a process. Now, if the second argument begins with a non-digit,
3082 it will be treated as a corefile. If it begins with a digit,
3083 GDB will attempt to attach it as a process, and if no such process
3084 is found, will then attempt to open it as a corefile.
3086 * Changes in ARM configurations.
3088 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3089 configuration is fully multi-arch.
3091 * New native configurations
3093 ARM NetBSD arm*-*-netbsd*
3094 x86 OpenBSD i[3456]86-*-openbsd*
3095 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3096 Sparc64 running FreeBSD sparc64-*-freebsd*
3100 Sanyo XStormy16 xstormy16-elf
3102 * OBSOLETE configurations and files
3104 Configurations that have been declared obsolete in this release have
3105 been commented out. Unless there is activity to revive these
3106 configurations, the next release of GDB will have their sources
3107 permanently REMOVED.
3109 AMD 29k family via UDI a29k-amd-udi, udi29k
3110 A29K VxWorks a29k-*-vxworks
3111 AMD 29000 embedded, using EBMON a29k-none-none
3112 AMD 29000 embedded with COFF a29k-none-coff
3113 AMD 29000 embedded with a.out a29k-none-aout
3115 testsuite/gdb.hp/gdb.threads-hp/ directory
3117 * REMOVED configurations and files
3119 TI TMS320C80 tic80-*-*
3121 PowerPC Solaris powerpcle-*-solaris*
3122 PowerPC Windows NT powerpcle-*-cygwin32
3123 PowerPC Netware powerpc-*-netware*
3124 Harris/CXUX m88k m88*-harris-cxux*
3125 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3126 ns32k-utek-sysv* ns32k-utek-*
3127 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3128 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3129 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3130 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3131 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3133 * Changes to command line processing
3135 The new `--args' feature can be used to specify command-line arguments
3136 for the inferior from gdb's command line.
3138 * Changes to key bindings
3140 There is a new `operate-and-get-next' function bound to `C-o'.
3142 *** Changes in GDB 5.1.1
3144 Fix compile problem on DJGPP.
3146 Fix a problem with floating-point registers on the i386 being
3149 Fix to stop GDB crashing on .debug_str debug info.
3151 Numerous documentation fixes.
3153 Numerous testsuite fixes.
3155 *** Changes in GDB 5.1:
3157 * New native configurations
3159 Alpha FreeBSD alpha*-*-freebsd*
3160 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3161 MIPS GNU/Linux mips*-*-linux*
3162 MIPS SGI Irix 6.x mips*-sgi-irix6*
3163 ia64 AIX ia64-*-aix*
3164 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3168 Motorola 68HC11 and 68HC12 m68hc11-elf
3170 UltraSparc running GNU/Linux sparc64-*-linux*
3172 * OBSOLETE configurations and files
3174 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3175 Harris/CXUX m88k m88*-harris-cxux*
3176 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3177 ns32k-utek-sysv* ns32k-utek-*
3178 TI TMS320C80 tic80-*-*
3180 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3181 PowerPC Solaris powerpcle-*-solaris*
3182 PowerPC Windows NT powerpcle-*-cygwin32
3183 PowerPC Netware powerpc-*-netware*
3184 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3185 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3186 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3187 Apple Macintosh (MPW) host N/A
3189 stuff.c (Program to stuff files into a specially prepared space in kdb)
3190 kdb-start.c (Main loop for the standalone kernel debugger)
3192 Configurations that have been declared obsolete in this release have
3193 been commented out. Unless there is activity to revive these
3194 configurations, the next release of GDB will have their sources
3195 permanently REMOVED.
3197 * REMOVED configurations and files
3199 Altos 3068 m68*-altos-*
3200 Convex c1-*-*, c2-*-*
3202 ARM RISCix arm-*-* (as host)
3206 * GDB has been converted to ISO C.
3208 GDB's source code has been converted to ISO C. In particular, the
3209 sources are fully protoized, and rely on standard headers being
3214 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3216 * The MI enabled by default.
3218 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3219 revised and enabled by default. Packages which use GDB as a debugging
3220 engine behind a UI or another front end are encouraged to switch to
3221 using the GDB/MI interface, instead of the old annotations interface
3222 which is now deprecated.
3224 * Support for debugging Pascal programs.
3226 GDB now includes support for debugging Pascal programs. The following
3227 main features are supported:
3229 - Pascal-specific data types such as sets;
3231 - automatic recognition of Pascal sources based on file-name
3234 - Pascal-style display of data types, variables, and functions;
3236 - a Pascal expression parser.
3238 However, some important features are not yet supported.
3240 - Pascal string operations are not supported at all;
3242 - there are some problems with boolean types;
3244 - Pascal type hexadecimal constants are not supported
3245 because they conflict with the internal variables format;
3247 - support for Pascal objects and classes is not full yet;
3249 - unlike Pascal, GDB is case-sensitive for symbol names.
3251 * Changes in completion.
3253 Commands such as `shell', `run' and `set args', which pass arguments
3254 to inferior programs, now complete on file names, similar to what
3255 users expect at the shell prompt.
3257 Commands which accept locations, such as `disassemble', `print',
3258 `breakpoint', `until', etc. now complete on filenames as well as
3259 program symbols. Thus, if you type "break foob TAB", and the source
3260 files linked into the programs include `foobar.c', that file name will
3261 be one of the candidates for completion. However, file names are not
3262 considered for completion after you typed a colon that delimits a file
3263 name from a name of a function in that file, as in "break foo.c:bar".
3265 `set demangle-style' completes on available demangling styles.
3267 * New platform-independent commands:
3269 It is now possible to define a post-hook for a command as well as a
3270 hook that runs before the command. For more details, see the
3271 documentation of `hookpost' in the GDB manual.
3273 * Changes in GNU/Linux native debugging.
3275 Support for debugging multi-threaded programs has been completely
3276 revised for all platforms except m68k and sparc. You can now debug as
3277 many threads as your system allows you to have.
3279 Attach/detach is supported for multi-threaded programs.
3281 Support for SSE registers was added for x86. This doesn't work for
3282 multi-threaded programs though.
3284 * Changes in MIPS configurations.
3286 Multi-arch support is enabled for all MIPS configurations.
3288 GDB can now be built as native debugger on SGI Irix 6.x systems for
3289 debugging n32 executables. (Debugging 64-bit executables is not yet
3292 * Unified support for hardware watchpoints in all x86 configurations.
3294 Most (if not all) native x86 configurations support hardware-assisted
3295 breakpoints and watchpoints in a unified manner. This support
3296 implements debug register sharing between watchpoints, which allows to
3297 put a virtually infinite number of watchpoints on the same address,
3298 and also supports watching regions up to 16 bytes with several debug
3301 The new maintenance command `maintenance show-debug-regs' toggles
3302 debugging print-outs in functions that insert, remove, and test
3303 watchpoints and hardware breakpoints.
3305 * Changes in the DJGPP native configuration.
3307 New command ``info dos sysinfo'' displays assorted information about
3308 the CPU, OS, memory, and DPMI server.
3310 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3311 display information about segment descriptors stored in GDT, LDT, and
3314 New commands ``info dos pde'' and ``info dos pte'' display entries
3315 from Page Directory and Page Tables (for now works with CWSDPMI only).
3316 New command ``info dos address-pte'' displays the Page Table entry for
3317 a given linear address.
3319 GDB can now pass command lines longer than 126 characters to the
3320 program being debugged (requires an update to the libdbg.a library
3321 which is part of the DJGPP development kit).
3323 DWARF2 debug info is now supported.
3325 It is now possible to `step' and `next' through calls to `longjmp'.
3327 * Changes in documentation.
3329 All GDB documentation was converted to GFDL, the GNU Free
3330 Documentation License.
3332 Tracepoints-related commands are now fully documented in the GDB
3335 TUI, the Text-mode User Interface, is now documented in the manual.
3337 Tracepoints-related commands are now fully documented in the GDB
3340 The "GDB Internals" manual now has an index. It also includes
3341 documentation of `ui_out' functions, GDB coding standards, x86
3342 hardware watchpoints, and memory region attributes.
3344 * GDB's version number moved to ``version.in''
3346 The Makefile variable VERSION has been replaced by the file
3347 ``version.in''. People creating GDB distributions should update the
3348 contents of this file.
3352 GUD support is now a standard part of the EMACS distribution.
3354 *** Changes in GDB 5.0:
3356 * Improved support for debugging FP programs on x86 targets
3358 Unified and much-improved support for debugging floating-point
3359 programs on all x86 targets. In particular, ``info float'' now
3360 displays the FP registers in the same format on all x86 targets, with
3361 greater level of detail.
3363 * Improvements and bugfixes in hardware-assisted watchpoints
3365 It is now possible to watch array elements, struct members, and
3366 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3367 on x86 targets no longer erroneously trigger when the address is
3370 * Improvements in the native DJGPP version of GDB
3372 The distribution now includes all the scripts and auxiliary files
3373 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3374 machines ``out of the box''.
3376 The DJGPP version can now debug programs that use signals. It is
3377 possible to catch signals that happened in the debuggee, deliver
3378 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3379 would kill the program being debugged.) Programs that hook hardware
3380 interrupts (keyboard, timer, etc.) can also be debugged.
3382 It is now possible to debug DJGPP programs that redirect their
3383 standard handles or switch them to raw (as opposed to cooked) mode, or
3384 even close them. The command ``run < foo > bar'' works as expected,
3385 and ``info terminal'' reports useful information about the debuggee's
3386 terminal, including raw/cooked mode, redirection, etc.
3388 The DJGPP version now uses termios functions for console I/O, which
3389 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3392 DOS-style file names with drive letters are now fully supported by
3395 It is now possible to debug DJGPP programs that switch their working
3396 directory. It is also possible to rerun the debuggee any number of
3397 times without restarting GDB; thus, you can use the same setup,
3398 breakpoints, etc. for many debugging sessions.
3400 * New native configurations
3402 ARM GNU/Linux arm*-*-linux*
3403 PowerPC GNU/Linux powerpc-*-linux*
3407 Motorola MCore mcore-*-*
3408 x86 VxWorks i[3456]86-*-vxworks*
3409 PowerPC VxWorks powerpc-*-vxworks*
3410 TI TMS320C80 tic80-*-*
3412 * OBSOLETE configurations
3414 Altos 3068 m68*-altos-*
3415 Convex c1-*-*, c2-*-*
3417 ARM RISCix arm-*-* (as host)
3420 Configurations that have been declared obsolete will be commented out,
3421 but the code will be left in place. If there is no activity to revive
3422 these configurations before the next release of GDB, the sources will
3423 be permanently REMOVED.
3425 * Gould support removed
3427 Support for the Gould PowerNode and NP1 has been removed.
3429 * New features for SVR4
3431 On SVR4 native platforms (such as Solaris), if you attach to a process
3432 without first loading a symbol file, GDB will now attempt to locate and
3433 load symbols from the running process's executable file.
3435 * Many C++ enhancements
3437 C++ support has been greatly improved. Overload resolution now works properly
3438 in almost all cases. RTTI support is on the way.
3440 * Remote targets can connect to a sub-program
3442 A popen(3) style serial-device has been added. This device starts a
3443 sub-process (such as a stand-alone simulator) and then communicates
3444 with that. The sub-program to run is specified using the syntax
3445 ``|<program> <args>'' vis:
3447 (gdb) set remotedebug 1
3448 (gdb) target extended-remote |mn10300-elf-sim program-args
3450 * MIPS 64 remote protocol
3452 A long standing bug in the mips64 remote protocol where by GDB
3453 expected certain 32 bit registers (ex SR) to be transfered as 32
3454 instead of 64 bits has been fixed.
3456 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3457 added to provide backward compatibility with older versions of GDB.
3459 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3461 The command ``set remotebinarydownload'' command has been replaced by
3462 ``set remote X-packet''. Other commands in ``set remote'' family
3463 include ``set remote P-packet''.
3465 * Breakpoint commands accept ranges.
3467 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3468 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3469 ``tracepoint passcount'' also accepts a range of tracepoints.
3471 * ``apropos'' command added.
3473 The ``apropos'' command searches through command names and
3474 documentation strings, printing out matches, making it much easier to
3475 try to find a command that does what you are looking for.
3479 A new machine oriented interface (MI) has been added to GDB. This
3480 interface is designed for debug environments running GDB as a separate
3481 process. This is part of the long term libGDB project. See the
3482 "GDB/MI" chapter of the GDB manual for further information. It can be
3483 enabled by configuring with:
3485 .../configure --enable-gdbmi
3487 *** Changes in GDB-4.18:
3489 * New native configurations
3491 HP-UX 10.20 hppa*-*-hpux10.20
3492 HP-UX 11.x hppa*-*-hpux11.0*
3493 M68K GNU/Linux m68*-*-linux*
3497 Fujitsu FR30 fr30-*-elf*
3498 Intel StrongARM strongarm-*-*
3499 Mitsubishi D30V d30v-*-*
3501 * OBSOLETE configurations
3503 Gould PowerNode, NP1 np1-*-*, pn-*-*
3505 Configurations that have been declared obsolete will be commented out,
3506 but the code will be left in place. If there is no activity to revive
3507 these configurations before the next release of GDB, the sources will
3508 be permanently REMOVED.
3512 As a compatibility experiment, GDB's source files buildsym.h and
3513 buildsym.c have been converted to pure standard C, no longer
3514 containing any K&R compatibility code. We believe that all systems in
3515 use today either come with a standard C compiler, or have a GCC port
3516 available. If this is not true, please report the affected
3517 configuration to bug-gdb@gnu.org immediately. See the README file for
3518 information about getting a standard C compiler if you don't have one
3523 GDB now uses readline 2.2.
3525 * set extension-language
3527 You can now control the mapping between filename extensions and source
3528 languages by using the `set extension-language' command. For instance,
3529 you can ask GDB to treat .c files as C++ by saying
3530 set extension-language .c c++
3531 The command `info extensions' lists all of the recognized extensions
3532 and their associated languages.
3534 * Setting processor type for PowerPC and RS/6000
3536 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3537 you can use the `set processor' command to specify what variant of the
3538 PowerPC family you are debugging. The command
3542 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3543 following PowerPC and RS6000 variants:
3545 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3546 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3548 403GC IBM PowerPC 403GC
3549 505 Motorola PowerPC 505
3550 860 Motorola PowerPC 860 or 850
3551 601 Motorola PowerPC 601
3552 602 Motorola PowerPC 602
3553 603 Motorola/IBM PowerPC 603 or 603e
3554 604 Motorola PowerPC 604 or 604e
3555 750 Motorola/IBM PowerPC 750 or 750
3557 At the moment, this command just tells GDB what to name the
3558 special-purpose processor registers. Since almost all the affected
3559 registers are inaccessible to user-level programs, this command is
3560 only useful for remote debugging in its present form.
3564 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3565 more extensive support for HP-UX. Added features include shared
3566 library support, kernel threads and hardware watchpoints for 11.00,
3567 support for HP's ANSI C and C++ compilers, and a compatibility mode
3568 for xdb and dbx commands.
3572 HP's donation includes the new concept of catchpoints, which is a
3573 generalization of the old catch command. On HP-UX, it is now possible
3574 to catch exec, fork, and vfork, as well as library loading.
3576 This means that the existing catch command has changed; its first
3577 argument now specifies the type of catch to be set up. See the
3578 output of "help catch" for a list of catchpoint types.
3580 * Debugging across forks
3582 On HP-UX, you can choose which process to debug when a fork() happens
3587 HP has donated a curses-based terminal user interface (TUI). To get
3588 it, build with --enable-tui. Although this can be enabled for any
3589 configuration, at present it only works for native HP debugging.
3591 * GDB remote protocol additions
3593 A new protocol packet 'X' that writes binary data is now available.
3594 Default behavior is to try 'X', then drop back to 'M' if the stub
3595 fails to respond. The settable variable `remotebinarydownload'
3596 allows explicit control over the use of 'X'.
3598 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3599 full 64-bit address. The command
3601 set remoteaddresssize 32
3603 can be used to revert to the old behaviour. For existing remote stubs
3604 the change should not be noticed, as the additional address information
3607 In order to assist in debugging stubs, you may use the maintenance
3608 command `packet' to send any text string to the stub. For instance,
3610 maint packet heythere
3612 sends the packet "$heythere#<checksum>". Note that it is very easy to
3613 disrupt a debugging session by sending the wrong packet at the wrong
3616 The compare-sections command allows you to compare section data on the
3617 target to what is in the executable file without uploading or
3618 downloading, by comparing CRC checksums.
3620 * Tracing can collect general expressions
3622 You may now collect general expressions at tracepoints. This requires
3623 further additions to the target-side stub; see tracepoint.c and
3624 doc/agentexpr.texi for further details.
3626 * mask-address variable for Mips
3628 For Mips targets, you may control the zeroing of the upper 32 bits of
3629 a 64-bit address by entering `set mask-address on'. This is mainly
3630 of interest to users of embedded R4xxx and R5xxx processors.
3632 * Higher serial baud rates
3634 GDB's serial code now allows you to specify baud rates 57600, 115200,
3635 230400, and 460800 baud. (Note that your host system may not be able
3636 to achieve all of these rates.)
3640 The i960 configuration now includes an initial implementation of a
3641 builtin simulator, contributed by Jim Wilson.
3644 *** Changes in GDB-4.17:
3646 * New native configurations
3648 Alpha GNU/Linux alpha*-*-linux*
3649 Unixware 2.x i[3456]86-unixware2*
3650 Irix 6.x mips*-sgi-irix6*
3651 PowerPC GNU/Linux powerpc-*-linux*
3652 PowerPC Solaris powerpcle-*-solaris*
3653 Sparc GNU/Linux sparc-*-linux*
3654 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3658 Argonaut Risc Chip (ARC) arc-*-*
3659 Hitachi H8/300S h8300*-*-*
3660 Matsushita MN10200 w/simulator mn10200-*-*
3661 Matsushita MN10300 w/simulator mn10300-*-*
3662 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3663 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3664 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3665 Mitsubishi D10V w/simulator d10v-*-*
3666 Mitsubishi M32R/D w/simulator m32r-*-elf*
3667 Tsqware Sparclet sparclet-*-*
3668 NEC V850 w/simulator v850-*-*
3670 * New debugging protocols
3672 ARM with RDI protocol arm*-*-*
3673 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3674 DDB and LSI variants of PMON protocol mips*-*-*
3675 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3676 PowerPC with SDS protocol powerpc{,le}-*-eabi
3677 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3681 All configurations can now understand and use the DWARF 2 debugging
3682 format. The choice is automatic, if the symbol file contains DWARF 2
3687 GDB now includes basic Java language support. This support is
3688 only useful with Java compilers that produce native machine code.
3690 * solib-absolute-prefix and solib-search-path
3692 For SunOS and SVR4 shared libraries, you may now set the prefix for
3693 loading absolute shared library symbol files, and the search path for
3694 locating non-absolute shared library symbol files.
3696 * Live range splitting
3698 GDB can now effectively debug code for which GCC has performed live
3699 range splitting as part of its optimization. See gdb/doc/LRS for
3700 more details on the expected format of the stabs information.
3704 GDB's support for the GNU Hurd, including thread debugging, has been
3705 updated to work with current versions of the Hurd.
3709 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3710 instruction set. ARM GDB automatically detects when Thumb
3711 instructions are in use, and adjusts disassembly and backtracing
3716 GDB's MIPS target configurations now handle the MIP16 16-bit
3721 GDB now includes support for overlays; if an executable has been
3722 linked such that multiple sections are based at the same address, GDB
3723 will decide which section to use for symbolic info. You can choose to
3724 control the decision manually, using overlay commands, or implement
3725 additional target-side support and use "overlay load-target" to bring
3726 in the overlay mapping. Do "help overlay" for more detail.
3730 The command "info symbol <address>" displays information about
3731 the symbol at the specified address.
3735 The standard remote protocol now includes an extension that allows
3736 asynchronous collection and display of trace data. This requires
3737 extensive support in the target-side debugging stub. Tracing mode
3738 includes a new interaction mode in GDB and new commands: see the
3739 file tracepoint.c for more details.
3743 Configurations for embedded MIPS now include a simulator contributed
3744 by Cygnus Solutions. The simulator supports the instruction sets
3745 of most MIPS variants.
3749 Sparc configurations may now include the ERC32 simulator contributed
3750 by the European Space Agency. The simulator is not built into
3751 Sparc targets by default; configure with --enable-sim to include it.
3755 For target configurations that may include multiple variants of a
3756 basic architecture (such as MIPS and SH), you may now set the
3757 architecture explicitly. "set arch" sets, "info arch" lists
3758 the possible architectures.
3760 *** Changes in GDB-4.16:
3762 * New native configurations
3764 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3765 M68K NetBSD m68k-*-netbsd*
3766 PowerPC AIX 4.x powerpc-*-aix*
3767 PowerPC MacOS powerpc-*-macos*
3768 PowerPC Windows NT powerpcle-*-cygwin32
3769 RS/6000 AIX 4.x rs6000-*-aix4*
3773 ARM with RDP protocol arm-*-*
3774 I960 with MON960 i960-*-coff
3775 MIPS VxWorks mips*-*-vxworks*
3776 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3777 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3779 Matra Sparclet sparclet-*-*
3783 The powerpc-eabi configuration now includes the PSIM simulator,
3784 contributed by Andrew Cagney, with assistance from Mike Meissner.
3785 PSIM is a very elaborate model of the PowerPC, including not only
3786 basic instruction set execution, but also details of execution unit
3787 performance and I/O hardware. See sim/ppc/README for more details.
3791 GDB now works with Solaris 2.5.
3793 * Windows 95/NT native
3795 GDB will now work as a native debugger on Windows 95 and Windows NT.
3796 To build it from source, you must use the "gnu-win32" environment,
3797 which uses a DLL to emulate enough of Unix to run the GNU tools.
3798 Further information, binaries, and sources are available at
3799 ftp.cygnus.com, under pub/gnu-win32.
3801 * dont-repeat command
3803 If a user-defined command includes the command `dont-repeat', then the
3804 command will not be repeated if the user just types return. This is
3805 useful if the command is time-consuming to run, so that accidental
3806 extra keystrokes don't run the same command many times.
3808 * Send break instead of ^C
3810 The standard remote protocol now includes an option to send a break
3811 rather than a ^C to the target in order to interrupt it. By default,
3812 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3814 * Remote protocol timeout
3816 The standard remote protocol includes a new variable `remotetimeout'
3817 that allows you to set the number of seconds before GDB gives up trying
3818 to read from the target. The default value is 2.
3820 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3822 By default GDB will automatically keep track of objects as they are
3823 loaded and unloaded by the dynamic linker. By using the command `set
3824 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3825 when shared library events occur, thus allowing you to set breakpoints
3826 in shared libraries which are explicitly loaded by the inferior.
3828 Note this feature does not work on hpux8. On hpux9 you must link
3829 /usr/lib/end.o into your program. This feature should work
3830 automatically on hpux10.
3832 * Irix 5.x hardware watchpoint support
3834 Irix 5 configurations now support the use of hardware watchpoints.
3836 * Mips protocol "SYN garbage limit"
3838 When debugging a Mips target using the `target mips' protocol, you
3839 may set the number of characters that GDB will ignore by setting
3840 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3841 every character. The default value is 1050.
3843 * Recording and replaying remote debug sessions
3845 If you set `remotelogfile' to the name of a file, gdb will write to it
3846 a recording of a remote debug session. This recording may then be
3847 replayed back to gdb using "gdbreplay". See gdbserver/README for
3848 details. This is useful when you have a problem with GDB while doing
3849 remote debugging; you can make a recording of the session and send it
3850 to someone else, who can then recreate the problem.
3852 * Speedups for remote debugging
3854 GDB includes speedups for downloading and stepping MIPS systems using
3855 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3856 and more efficient S-record downloading.
3858 * Memory use reductions and statistics collection
3860 GDB now uses less memory and reports statistics about memory usage.
3861 Try the `maint print statistics' command, for example.
3863 *** Changes in GDB-4.15:
3865 * Psymtabs for XCOFF
3867 The symbol reader for AIX GDB now uses partial symbol tables. This
3868 can greatly improve startup time, especially for large executables.
3870 * Remote targets use caching
3872 Remote targets now use a data cache to speed up communication with the
3873 remote side. The data cache could lead to incorrect results because
3874 it doesn't know about volatile variables, thus making it impossible to
3875 debug targets which use memory mapped I/O devices. `set remotecache
3876 off' turns the the data cache off.
3878 * Remote targets may have threads
3880 The standard remote protocol now includes support for multiple threads
3881 in the target system, using new protocol commands 'H' and 'T'. See
3882 gdb/remote.c for details.
3886 If GDB is configured with `--enable-netrom', then it will include
3887 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3888 acts as though it is a bank of ROM on the target board, but you can
3889 write into it over the network. GDB's support consists only of
3890 support for fast loading into the emulated ROM; to debug, you must use
3891 another protocol, such as standard remote protocol. The usual
3892 sequence is something like
3894 target nrom <netrom-hostname>
3896 target remote <netrom-hostname>:1235
3900 GDB now includes support for the Apple Macintosh, as a host only. It
3901 may be run as either an MPW tool or as a standalone application, and
3902 it can debug through the serial port. All the usual GDB commands are
3903 available, but to the target command, you must supply "serial" as the
3904 device type instead of "/dev/ttyXX". See mpw-README in the main
3905 directory for more information on how to build. The MPW configuration
3906 scripts */mpw-config.in support only a few targets, and only the
3907 mips-idt-ecoff target has been tested.
3911 GDB configuration now uses autoconf. This is not user-visible,
3912 but does simplify configuration and building.
3916 GDB now supports hpux10.
3918 *** Changes in GDB-4.14:
3920 * New native configurations
3922 x86 FreeBSD i[345]86-*-freebsd
3923 x86 NetBSD i[345]86-*-netbsd
3924 NS32k NetBSD ns32k-*-netbsd
3925 Sparc NetBSD sparc-*-netbsd
3929 A29K VxWorks a29k-*-vxworks
3930 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3931 CPU32 EST-300 emulator m68*-*-est*
3932 PowerPC ELF powerpc-*-elf
3935 * Alpha OSF/1 support for procfs
3937 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3938 possible to attach to running processes. As the mounting of the /proc
3939 filesystem is optional on the Alpha, GDB automatically determines
3940 the availability of /proc during startup. This can lead to problems
3941 if /proc is unmounted after GDB has been started.
3943 * Arguments to user-defined commands
3945 User commands may accept up to 10 arguments separated by whitespace.
3946 Arguments are accessed within the user command via $arg0..$arg9. A
3949 print $arg0 + $arg1 + $arg2
3951 To execute the command use:
3954 Defines the command "adder" which prints the sum of its three arguments.
3955 Note the arguments are text substitutions, so they may reference variables,
3956 use complex expressions, or even perform inferior function calls.
3958 * New `if' and `while' commands
3960 This makes it possible to write more sophisticated user-defined
3961 commands. Both commands take a single argument, which is the
3962 expression to evaluate, and must be followed by the commands to
3963 execute, one per line, if the expression is nonzero, the list being
3964 terminated by the word `end'. The `if' command list may include an
3965 `else' word, which causes the following commands to be executed only
3966 if the expression is zero.
3968 * Fortran source language mode
3970 GDB now includes partial support for Fortran 77. It will recognize
3971 Fortran programs and can evaluate a subset of Fortran expressions, but
3972 variables and functions may not be handled correctly. GDB will work
3973 with G77, but does not yet know much about symbols emitted by other
3976 * Better HPUX support
3978 Most debugging facilities now work on dynamic executables for HPPAs
3979 running hpux9 or later. You can attach to running dynamically linked
3980 processes, but by default the dynamic libraries will be read-only, so
3981 for instance you won't be able to put breakpoints in them. To change
3982 that behavior do the following before running the program:
3988 This will cause the libraries to be mapped private and read-write.
3989 To revert to the normal behavior, do this:
3995 You cannot set breakpoints or examine data in the library until after
3996 the library is loaded if the function/data symbols do not have
3999 GDB can now also read debug symbols produced by the HP C compiler on
4000 HPPAs (sorry, no C++, Fortran or 68k support).
4002 * Target byte order now dynamically selectable
4004 You can choose which byte order to use with a target system, via the
4005 commands "set endian big" and "set endian little", and you can see the
4006 current setting by using "show endian". You can also give the command
4007 "set endian auto", in which case GDB will use the byte order
4008 associated with the executable. Currently, only embedded MIPS
4009 configurations support dynamic selection of target byte order.
4011 * New DOS host serial code
4013 This version uses DPMI interrupts to handle buffered I/O, so you
4014 no longer need to run asynctsr when debugging boards connected to
4017 *** Changes in GDB-4.13:
4019 * New "complete" command
4021 This lists all the possible completions for the rest of the line, if it
4022 were to be given as a command itself. This is intended for use by emacs.
4024 * Trailing space optional in prompt
4026 "set prompt" no longer adds a space for you after the prompt you set. This
4027 allows you to set a prompt which ends in a space or one that does not.
4029 * Breakpoint hit counts
4031 "info break" now displays a count of the number of times the breakpoint
4032 has been hit. This is especially useful in conjunction with "ignore"; you
4033 can ignore a large number of breakpoint hits, look at the breakpoint info
4034 to see how many times the breakpoint was hit, then run again, ignoring one
4035 less than that number, and this will get you quickly to the last hit of
4038 * Ability to stop printing at NULL character
4040 "set print null-stop" will cause GDB to stop printing the characters of
4041 an array when the first NULL is encountered. This is useful when large
4042 arrays actually contain only short strings.
4044 * Shared library breakpoints
4046 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4047 breakpoints in shared libraries before the executable is run.
4049 * Hardware watchpoints
4051 There is a new hardware breakpoint for the watch command for sparclite
4052 targets. See gdb/sparclite/hw_breakpoint.note.
4054 Hardware watchpoints are also now supported under GNU/Linux.
4058 Annotations have been added. These are for use with graphical interfaces,
4059 and are still experimental. Currently only gdba.el uses these.
4061 * Improved Irix 5 support
4063 GDB now works properly with Irix 5.2.
4065 * Improved HPPA support
4067 GDB now works properly with the latest GCC and GAS.
4069 * New native configurations
4071 Sequent PTX4 i[34]86-sequent-ptx4
4072 HPPA running OSF/1 hppa*-*-osf*
4073 Atari TT running SVR4 m68*-*-sysv4*
4074 RS/6000 LynxOS rs6000-*-lynxos*
4078 OS/9000 i[34]86-*-os9k
4079 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4082 * Hitachi SH7000 and E7000-PC ICE support
4084 There is now support for communicating with the Hitachi E7000-PC ICE.
4085 This is available automatically when GDB is configured for the SH.
4089 As usual, a variety of small fixes and improvements, both generic
4090 and configuration-specific. See the ChangeLog for more detail.
4092 *** Changes in GDB-4.12:
4094 * Irix 5 is now supported
4098 GDB-4.12 on the HPPA has a number of changes which make it unable
4099 to debug the output from the currently released versions of GCC and
4100 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4101 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4102 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4105 *** Changes in GDB-4.11:
4107 * User visible changes:
4111 The "set remotedebug" option is now consistent between the mips remote
4112 target, remote targets using the gdb-specific protocol, UDI (AMD's
4113 debug protocol for the 29k) and the 88k bug monitor. It is now an
4114 integer specifying a debug level (normally 0 or 1, but 2 means more
4115 debugging info for the mips target).
4117 * DEC Alpha native support
4119 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4120 debug info, but GDB works fairly well with the DEC compiler and should
4121 work with a future GCC release. See the README file for a few
4122 Alpha-specific notes.
4124 * Preliminary thread implementation
4126 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4128 * LynxOS native and target support for 386
4130 This release has been hosted on LynxOS 2.2, and also can be configured
4131 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4134 * Improvements in C++ mangling/demangling.
4136 This release has much better g++ debugging, specifically in name
4137 mangling/demangling, virtual function calls, print virtual table,
4138 call methods, ...etc.
4140 *** Changes in GDB-4.10:
4142 * User visible changes:
4144 Remote debugging using the GDB-specific (`target remote') protocol now
4145 supports the `load' command. This is only useful if you have some
4146 other way of getting the stub to the target system, and you can put it
4147 somewhere in memory where it won't get clobbered by the download.
4149 Filename completion now works.
4151 When run under emacs mode, the "info line" command now causes the
4152 arrow to point to the line specified. Also, "info line" prints
4153 addresses in symbolic form (as well as hex).
4155 All vxworks based targets now support a user settable option, called
4156 vxworks-timeout. This option represents the number of seconds gdb
4157 should wait for responses to rpc's. You might want to use this if
4158 your vxworks target is, perhaps, a slow software simulator or happens
4159 to be on the far side of a thin network line.
4163 This release contains support for using a DEC alpha as a GDB host for
4164 cross debugging. Native alpha debugging is not supported yet.
4167 *** Changes in GDB-4.9:
4171 This is the first GDB release which is accompanied by a matching testsuite.
4172 The testsuite requires installation of dejagnu, which should be available
4173 via ftp from most sites that carry GNU software.
4177 'Cfront' style demangling has had its name changed to 'ARM' style, to
4178 emphasize that it was written from the specifications in the C++ Annotated
4179 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4180 disclaimers, it still generated too much confusion with users attempting to
4181 use gdb with AT&T cfront.
4185 GDB now uses a standard remote interface to a simulator library.
4186 So far, the library contains simulators for the Zilog Z8001/2, the
4187 Hitachi H8/300, H8/500 and Super-H.
4189 * New targets supported
4191 H8/300 simulator h8300-hitachi-hms or h8300hms
4192 H8/500 simulator h8500-hitachi-hms or h8500hms
4193 SH simulator sh-hitachi-hms or sh
4194 Z8000 simulator z8k-zilog-none or z8ksim
4195 IDT MIPS board over serial line mips-idt-ecoff
4197 Cross-debugging to GO32 targets is supported. It requires a custom
4198 version of the i386-stub.c module which is integrated with the
4199 GO32 memory extender.
4201 * New remote protocols
4203 MIPS remote debugging protocol.
4205 * New source languages supported
4207 This version includes preliminary support for Chill, a Pascal like language
4208 used by telecommunications companies. Chill support is also being integrated
4209 into the GNU compiler, but we don't know when it will be publically available.
4212 *** Changes in GDB-4.8:
4214 * HP Precision Architecture supported
4216 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4217 version of this support was available as a set of patches from the
4218 University of Utah. GDB does not support debugging of programs
4219 compiled with the HP compiler, because HP will not document their file
4220 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4221 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4223 Many problems in the preliminary version have been fixed.
4225 * Faster and better demangling
4227 We have improved template demangling and fixed numerous bugs in the GNU style
4228 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4229 character types (wchar_t) are now supported. Demangling of each symbol is now
4230 only done once, and is cached when the symbol table for a file is read in.
4231 This results in a small increase in memory usage for C programs, a moderate
4232 increase in memory usage for C++ programs, and a fantastic speedup in
4235 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4236 from the specifications in the Annotated Reference Manual, which AT&T's
4237 compiler does not actually implement.
4239 * G++ multiple inheritance compiler problem
4241 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4242 inheritance lattices was reworked to properly discover ambiguities. We
4243 recently found an example which causes this new algorithm to fail in a
4244 very subtle way, producing bad debug information for those classes.
4245 The file 'gcc.patch' (in this directory) can be applied to gcc to
4246 circumvent the problem. A future GCC release will contain a complete
4249 The previous G++ debug info problem (mentioned below for the gdb-4.7
4250 release) is fixed in gcc version 2.3.2.
4252 * Improved configure script
4254 The `configure' script will now attempt to guess your system type if
4255 you don't supply a host system type. The old scheme of supplying a
4256 host system triplet is preferable over using this. All the magic is
4257 done in the new `config.guess' script. Examine it for details.
4259 We have also brought our configure script much more in line with the FSF's
4260 version. It now supports the --with-xxx options. In particular,
4261 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4262 The resulting GDB will not be able to read arbitrary object file formats --
4263 only the format ``expected'' to be used on the configured target system.
4264 We hope to make this the default in a future release.
4266 * Documentation improvements
4268 There's new internal documentation on how to modify GDB, and how to
4269 produce clean changes to the code. We implore people to read it
4270 before submitting changes.
4272 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4273 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4274 `info' files are also provided. To build `info' files from scratch,
4275 you will need the latest `makeinfo' release, which will be available in
4276 a future texinfo-X.Y release.
4278 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4279 We're not sure exactly which versions have this problem, but it has
4280 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4281 or better. If that isn't possible, there is a patch in
4282 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4283 around this problem.
4287 GDB now supports array constants that can be used in expressions typed in by
4288 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4289 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4292 The new directory `gdb/sparclite' contains a program that demonstrates
4293 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4295 * New native hosts supported
4297 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4298 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4300 * New targets supported
4302 AMD 29k family via UDI a29k-amd-udi or udi29k
4304 * New file formats supported
4306 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4307 HPUX core files, and SCO 3.2v2 core files.
4311 Attaching to processes now works again; thanks for the many bug reports.
4313 We have also stomped on a bunch of core dumps caused by
4314 printf_filtered("%s") problems.
4316 We eliminated a copyright problem on the rpc and ptrace header files
4317 for VxWorks, which was discovered at the last minute during the 4.7
4318 release. You should now be able to build a VxWorks GDB.
4320 You can now interrupt gdb while an attached process is running. This
4321 will cause the attached process to stop, and give control back to GDB.
4323 We fixed problems caused by using too many file descriptors
4324 for reading symbols from object files and libraries. This was
4325 especially a problem for programs that used many (~100) shared
4328 The `step' command now only enters a subroutine if there is line number
4329 information for the subroutine. Otherwise it acts like the `next'
4330 command. Previously, `step' would enter subroutines if there was
4331 any debugging information about the routine. This avoids problems
4332 when using `cc -g1' on MIPS machines.
4334 * Internal improvements
4336 GDB's internal interfaces have been improved to make it easier to support
4337 debugging of multiple languages in the future.
4339 GDB now uses a common structure for symbol information internally.
4340 Minimal symbols (derived from linkage symbols in object files), partial
4341 symbols (from a quick scan of debug information), and full symbols
4342 contain a common subset of information, making it easier to write
4343 shared code that handles any of them.
4345 * New command line options
4347 We now accept --silent as an alias for --quiet.
4351 The memory-mapped-malloc library is now licensed under the GNU Library
4352 General Public License.
4354 *** Changes in GDB-4.7:
4356 * Host/native/target split
4358 GDB has had some major internal surgery to untangle the support for
4359 hosts and remote targets. Now, when you configure GDB for a remote
4360 target, it will no longer load in all of the support for debugging
4361 local programs on the host. When fully completed and tested, this will
4362 ensure that arbitrary host/target combinations are possible.
4364 The primary conceptual shift is to separate the non-portable code in
4365 GDB into three categories. Host specific code is required any time GDB
4366 is compiled on that host, regardless of the target. Target specific
4367 code relates to the peculiarities of the target, but can be compiled on
4368 any host. Native specific code is everything else: it can only be
4369 built when the host and target are the same system. Child process
4370 handling and core file support are two common `native' examples.
4372 GDB's use of /proc for controlling Unix child processes is now cleaner.
4373 It has been split out into a single module under the `target_ops' vector,
4374 plus two native-dependent functions for each system that uses /proc.
4376 * New hosts supported
4378 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4379 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4380 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4382 * New targets supported
4384 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4385 68030 and CPU32 m68030-*-*, m68332-*-*
4387 * New native hosts supported
4389 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4390 (386bsd is not well tested yet)
4391 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4393 * New file formats supported
4395 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4396 supports reading of `a.out.adobe' object files, which are an a.out
4397 format extended with minimal information about multiple sections.
4401 `show copying' is the same as the old `info copying'.
4402 `show warranty' is the same as `info warrantee'.
4403 These were renamed for consistency. The old commands continue to work.
4405 `info handle' is a new alias for `info signals'.
4407 You can now define pre-command hooks, which attach arbitrary command
4408 scripts to any command. The commands in the hook will be executed
4409 prior to the user's command. You can also create a hook which will be
4410 executed whenever the program stops. See gdb.texinfo.
4414 We now deal with Cfront style name mangling, and can even extract type
4415 info from mangled symbols. GDB can automatically figure out which
4416 symbol mangling style your C++ compiler uses.
4418 Calling of methods and virtual functions has been improved as well.
4422 The crash that occured when debugging Sun Ansi-C compiled binaries is
4423 fixed. This was due to mishandling of the extra N_SO stabs output
4426 We also finally got Ultrix 4.2 running in house, and fixed core file
4427 support, with help from a dozen people on the net.
4429 John M. Farrell discovered that the reason that single-stepping was so
4430 slow on all of the Mips based platforms (primarily SGI and DEC) was
4431 that we were trying to demangle and lookup a symbol used for internal
4432 purposes on every instruction that was being stepped through. Changing
4433 the name of that symbol so that it couldn't be mistaken for a C++
4434 mangled symbol sped things up a great deal.
4436 Rich Pixley sped up symbol lookups in general by getting much smarter
4437 about when C++ symbol mangling is necessary. This should make symbol
4438 completion (TAB on the command line) much faster. It's not as fast as
4439 we'd like, but it's significantly faster than gdb-4.6.
4443 A new user controllable variable 'call_scratch_address' can
4444 specify the location of a scratch area to be used when GDB
4445 calls a function in the target. This is necessary because the
4446 usual method of putting the scratch area on the stack does not work
4447 in systems that have separate instruction and data spaces.
4449 We integrated changes to support the 29k UDI (Universal Debugger
4450 Interface), but discovered at the last minute that we didn't have all
4451 of the appropriate copyright paperwork. We are working with AMD to
4452 resolve this, and hope to have it available soon.
4456 We have sped up the remote serial line protocol, especially for targets
4457 with lots of registers. It now supports a new `expedited status' ('T')
4458 message which can be used in place of the existing 'S' status message.
4459 This allows the remote stub to send only the registers that GDB
4460 needs to make a quick decision about single-stepping or conditional
4461 breakpoints, eliminating the need to fetch the entire register set for
4462 each instruction being stepped through.
4464 The GDB remote serial protocol now implements a write-through cache for
4465 registers, only re-reading the registers if the target has run.
4467 There is also a new remote serial stub for SPARC processors. You can
4468 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4469 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4470 processor with a serial port.
4474 Configure.in files have become much easier to read and modify. A new
4475 `table driven' format makes it more obvious what configurations are
4476 supported, and what files each one uses.
4480 There is a new opcodes library which will eventually contain all of the
4481 disassembly routines and opcode tables. At present, it only contains
4482 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4483 disassembler (binutils/objdump) to share these routines.
4485 The libiberty library is now copylefted under the GNU Library General
4486 Public License. This allows more liberal use, and was done so libg++
4487 can use it. This makes no difference to GDB, since the Library License
4488 grants all the rights from the General Public License.
4492 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4493 reference to the stabs symbol info used by the debugger. It is (as far
4494 as we know) the only published document on this fascinating topic. We
4495 encourage you to read it, compare it to the stabs information on your
4496 system, and send improvements on the document in general (to
4497 bug-gdb@prep.ai.mit.edu).
4499 And, of course, many bugs have been fixed.
4502 *** Changes in GDB-4.6:
4504 * Better support for C++ function names
4506 GDB now accepts as input the "demangled form" of C++ overloaded function
4507 names and member function names, and can do command completion on such names
4508 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4509 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4510 Make use of command completion, it is your friend.
4512 GDB also now accepts a variety of C++ mangled symbol formats. They are
4513 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4514 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4515 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4516 for the list of formats.
4518 * G++ symbol mangling problem
4520 Recent versions of gcc have a bug in how they emit debugging information for
4521 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4522 directory) can be applied to gcc to fix the problem. Alternatively, if you
4523 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4524 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4525 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4528 * New 'maintenance' command
4530 All of the commands related to hacking GDB internals have been moved out of
4531 the main command set, and now live behind the 'maintenance' command. This
4532 can also be abbreviated as 'mt'. The following changes were made:
4534 dump-me -> maintenance dump-me
4535 info all-breakpoints -> maintenance info breakpoints
4536 printmsyms -> maintenance print msyms
4537 printobjfiles -> maintenance print objfiles
4538 printpsyms -> maintenance print psymbols
4539 printsyms -> maintenance print symbols
4541 The following commands are new:
4543 maintenance demangle Call internal GDB demangler routine to
4544 demangle a C++ link name and prints the result.
4545 maintenance print type Print a type chain for a given symbol
4547 * Change to .gdbinit file processing
4549 We now read the $HOME/.gdbinit file before processing the argv arguments
4550 (e.g. reading symbol files or core files). This allows global parameters to
4551 be set, which will apply during the symbol reading. The ./.gdbinit is still
4552 read after argv processing.
4554 * New hosts supported
4556 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4558 GNU/Linux support i386-unknown-linux or linux
4560 We are also including code to support the HP/PA running BSD and HPUX. This
4561 is almost guaranteed not to work, as we didn't have time to test or build it
4562 for this release. We are including it so that the more adventurous (or
4563 masochistic) of you can play with it. We also had major problems with the
4564 fact that the compiler that we got from HP doesn't support the -g option.
4567 * New targets supported
4569 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4571 * More smarts about finding #include files
4573 GDB now remembers the compilation directory for all include files, and for
4574 all files from which C is generated (like yacc and lex sources). This
4575 greatly improves GDB's ability to find yacc/lex sources, and include files,
4576 especially if you are debugging your program from a directory different from
4577 the one that contains your sources.
4579 We also fixed a bug which caused difficulty with listing and setting
4580 breakpoints in include files which contain C code. (In the past, you had to
4581 try twice in order to list an include file that you hadn't looked at before.)
4583 * Interesting infernals change
4585 GDB now deals with arbitrary numbers of sections, where the symbols for each
4586 section must be relocated relative to that section's landing place in the
4587 target's address space. This work was needed to support ELF with embedded
4588 stabs used by Solaris-2.0.
4590 * Bug fixes (of course!)
4592 There have been loads of fixes for the following things:
4593 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4594 i960, stabs, DOS(GO32), procfs, etc...
4596 See the ChangeLog for details.
4598 *** Changes in GDB-4.5:
4600 * New machines supported (host and target)
4602 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4604 SGI Irix-4.x mips-sgi-irix4 or iris4
4606 * New malloc package
4608 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4609 Mmalloc is capable of handling mutiple heaps of memory. It is also
4610 capable of saving a heap to a file, and then mapping it back in later.
4611 This can be used to greatly speedup the startup of GDB by using a
4612 pre-parsed symbol table which lives in a mmalloc managed heap. For
4613 more details, please read mmalloc/mmalloc.texi.
4617 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4618 'help info proc' for details.
4620 * MIPS ecoff symbol table format
4622 The code that reads MIPS symbol table format is now supported on all hosts.
4623 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4626 * File name changes for MS-DOS
4628 Many files in the config directories have been renamed to make it easier to
4629 support GDB on MS-DOSe systems (which have very restrictive file name
4630 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4631 environment) is close to working but has some remaining problems. Note
4632 that debugging of DOS programs is not supported, due to limitations
4633 in the ``operating system'', but it can be used to host cross-debugging.
4635 * Cross byte order fixes
4637 Many fixes have been made to support cross debugging of Sparc and MIPS
4638 targets from hosts whose byte order differs.
4640 * New -mapped and -readnow options
4642 If memory-mapped files are available on your system through the 'mmap'
4643 system call, you can use the -mapped option on the `file' or
4644 `symbol-file' commands to cause GDB to write the symbols from your
4645 program into a reusable file. If the program you are debugging is
4646 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4647 Future GDB debugging sessions will notice the presence of this file,
4648 and will quickly map in symbol information from it, rather than reading
4649 the symbol table from the executable program. Using the '-mapped'
4650 option in a GDB `file' or `symbol-file' command has the same effect as
4651 starting GDB with the '-mapped' command-line option.
4653 You can cause GDB to read the entire symbol table immediately by using
4654 the '-readnow' option with any of the commands that load symbol table
4655 information (or on the GDB command line). This makes the command
4656 slower, but makes future operations faster.
4658 The -mapped and -readnow options are typically combined in order to
4659 build a `fred.syms' file that contains complete symbol information.
4660 A simple GDB invocation to do nothing but build a `.syms' file for future
4663 gdb -batch -nx -mapped -readnow programname
4665 The `.syms' file is specific to the host machine on which GDB is run.
4666 It holds an exact image of GDB's internal symbol table. It cannot be
4667 shared across multiple host platforms.
4669 * longjmp() handling
4671 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4672 siglongjmp() without losing control. This feature has not yet been ported to
4673 all systems. It currently works on many 386 platforms, all MIPS-based
4674 platforms (SGI, DECstation, etc), and Sun3/4.
4678 Preliminary work has been put in to support the new Solaris OS from Sun. At
4679 this time, it can control and debug processes, but it is not capable of
4684 As always, many many bug fixes. The major areas were with g++, and mipsread.
4685 People using the MIPS-based platforms should experience fewer mysterious
4686 crashes and trashed symbol tables.
4688 *** Changes in GDB-4.4:
4690 * New machines supported (host and target)
4692 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4694 BSD Reno on Vax vax-dec-bsd
4695 Ultrix on Vax vax-dec-ultrix
4697 * New machines supported (target)
4699 AMD 29000 embedded, using EBMON a29k-none-none
4703 GDB continues to improve its handling of C++. `References' work better.
4704 The demangler has also been improved, and now deals with symbols mangled as
4705 per the Annotated C++ Reference Guide.
4707 GDB also now handles `stabs' symbol information embedded in MIPS
4708 `ecoff' symbol tables. Since the ecoff format was not easily
4709 extensible to handle new languages such as C++, this appeared to be a
4710 good way to put C++ debugging info into MIPS binaries. This option
4711 will be supported in the GNU C compiler, version 2, when it is
4714 * New features for SVR4
4716 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4717 shared libraries. Debugging dynamically linked programs should present
4718 only minor differences from debugging statically linked programs.
4720 The `info proc' command will print out information about any process
4721 on an SVR4 system (including the one you are debugging). At the moment,
4722 it prints the address mappings of the process.
4724 If you bring up GDB on another SVR4 system, please send mail to
4725 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4727 * Better dynamic linking support in SunOS
4729 Reading symbols from shared libraries which contain debugging symbols
4730 now works properly. However, there remain issues such as automatic
4731 skipping of `transfer vector' code during function calls, which
4732 make it harder to debug code in a shared library, than to debug the
4733 same code linked statically.
4737 GDB is now using the latest `getopt' routines from the FSF. This
4738 version accepts the -- prefix for options with long names. GDB will
4739 continue to accept the old forms (-option and +option) as well.
4740 Various single letter abbreviations for options have been explicity
4741 added to the option table so that they won't get overshadowed in the
4742 future by other options that begin with the same letter.
4746 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4747 Many assorted bugs have been handled. Many more remain to be handled.
4748 See the various ChangeLog files (primarily in gdb and bfd) for details.
4751 *** Changes in GDB-4.3:
4753 * New machines supported (host and target)
4755 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4756 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4757 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4759 * Almost SCO Unix support
4761 We had hoped to support:
4762 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4763 (except for core file support), but we discovered very late in the release
4764 that it has problems with process groups that render gdb unusable. Sorry
4765 about that. I encourage people to fix it and post the fixes.
4767 * Preliminary ELF and DWARF support
4769 GDB can read ELF object files on System V Release 4, and can handle
4770 debugging records for C, in DWARF format, in ELF files. This support
4771 is preliminary. If you bring up GDB on another SVR4 system, please
4772 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4777 GDB now uses the latest `readline' library. One user-visible change
4778 is that two tabs will list possible command completions, which previously
4779 required typing M-? (meta-question mark, or ESC ?).
4783 The `stepi' bug that many of you noticed has been squashed.
4784 Many bugs in C++ have been handled. Many more remain to be handled.
4785 See the various ChangeLog files (primarily in gdb and bfd) for details.
4787 * State of the MIPS world (in case you wondered):
4789 GDB can understand the symbol tables emitted by the compilers
4790 supplied by most vendors of MIPS-based machines, including DEC. These
4791 symbol tables are in a format that essentially nobody else uses.
4793 Some versions of gcc come with an assembler post-processor called
4794 mips-tfile. This program is required if you want to do source-level
4795 debugging of gcc-compiled programs. I believe FSF does not ship
4796 mips-tfile with gcc version 1, but it will eventually come with gcc
4799 Debugging of g++ output remains a problem. g++ version 1.xx does not
4800 really support it at all. (If you're lucky, you should be able to get
4801 line numbers and stack traces to work, but no parameters or local
4802 variables.) With some work it should be possible to improve the
4805 When gcc version 2 is released, you will have somewhat better luck.
4806 However, even then you will get confusing results for inheritance and
4809 We will eventually provide full debugging of g++ output on
4810 DECstations. This will probably involve some kind of stabs-in-ecoff
4811 encapulation, but the details have not been worked out yet.
4814 *** Changes in GDB-4.2:
4816 * Improved configuration
4818 Only one copy of `configure' exists now, and it is not self-modifying.
4819 Porting BFD is simpler.
4823 The `step' and `next' commands now only stop at the first instruction
4824 of a source line. This prevents the multiple stops that used to occur
4825 in switch statements, for-loops, etc. `Step' continues to stop if a
4826 function that has debugging information is called within the line.
4830 Lots of small bugs fixed. More remain.
4832 * New host supported (not target)
4834 Intel 386 PC clone running Mach i386-none-mach
4837 *** Changes in GDB-4.1:
4839 * Multiple source language support
4841 GDB now has internal scaffolding to handle several source languages.
4842 It determines the type of each source file from its filename extension,
4843 and will switch expression parsing and number formatting to match the
4844 language of the function in the currently selected stack frame.
4845 You can also specifically set the language to be used, with
4846 `set language c' or `set language modula-2'.
4850 GDB now has preliminary support for the GNU Modula-2 compiler,
4851 currently under development at the State University of New York at
4852 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4853 continue through the fall of 1991 and into 1992.
4855 Other Modula-2 compilers are currently not supported, and attempting to
4856 debug programs compiled with them will likely result in an error as the
4857 symbol table is read. Feel free to work on it, though!
4859 There are hooks in GDB for strict type checking and range checking,
4860 in the `Modula-2 philosophy', but they do not currently work.
4864 GDB can now write to executable and core files (e.g. patch
4865 a variable's value). You must turn this switch on, specify
4866 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4867 by assigning a new value to a variable. Modifications take
4870 * Automatic SunOS shared library reading
4872 When you run your program, GDB automatically determines where its
4873 shared libraries (if any) have been loaded, and reads their symbols.
4874 The `share' command is no longer needed. This also works when
4875 examining core files.
4879 You can specify the number of lines that the `list' command shows.
4882 * New machines supported (host and target)
4884 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4885 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4886 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4888 * New hosts supported (not targets)
4890 IBM RT/PC: romp-ibm-aix or rtpc
4892 * New targets supported (not hosts)
4894 AMD 29000 embedded with COFF a29k-none-coff
4895 AMD 29000 embedded with a.out a29k-none-aout
4896 Ultracomputer remote kernel debug a29k-nyu-kern
4898 * New remote interfaces
4904 *** Changes in GDB-4.0:
4908 Wide output is wrapped at good places to make the output more readable.
4910 Gdb now supports cross-debugging from a host machine of one type to a
4911 target machine of another type. Communication with the target system
4912 is over serial lines. The ``target'' command handles connecting to the
4913 remote system; the ``load'' command will download a program into the
4914 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4915 also supports debugging of realtime processes running under VxWorks,
4916 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4917 stub on the target system.
4919 New CPUs supported include the AMD 29000 and Intel 960.
4921 GDB now reads object files and symbol tables via a ``binary file''
4922 library, which allows a single copy of GDB to debug programs of multiple
4923 object file types such as a.out and coff.
4925 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4926 refcard.dvi and refcard.ps are available to format it).
4929 * Control-Variable user interface simplified
4931 All variables that control the operation of the debugger can be set
4932 by the ``set'' command, and displayed by the ``show'' command.
4934 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4935 ``Show prompt'' produces the response:
4936 Gdb's prompt is new-gdb=>.
4938 What follows are the NEW set commands. The command ``help set'' will
4939 print a complete list of old and new set commands. ``help set FOO''
4940 will give a longer description of the variable FOO. ``show'' will show
4941 all of the variable descriptions and their current settings.
4943 confirm on/off: Enables warning questions for operations that are
4944 hard to recover from, e.g. rerunning the program while
4945 it is already running. Default is ON.
4947 editing on/off: Enables EMACS style command line editing
4948 of input. Previous lines can be recalled with
4949 control-P, the current line can be edited with control-B,
4950 you can search for commands with control-R, etc.
4953 history filename NAME: NAME is where the gdb command history
4954 will be stored. The default is .gdb_history,
4955 or the value of the environment variable
4958 history size N: The size, in commands, of the command history. The
4959 default is 256, or the value of the environment variable
4962 history save on/off: If this value is set to ON, the history file will
4963 be saved after exiting gdb. If set to OFF, the
4964 file will not be saved. The default is OFF.
4966 history expansion on/off: If this value is set to ON, then csh-like
4967 history expansion will be performed on
4968 command line input. The default is OFF.
4970 radix N: Sets the default radix for input and output. It can be set
4971 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4972 in the current radix, so "set radix 10" is always a no-op.
4974 height N: This integer value is the number of lines on a page. Default
4975 is 24, the current `stty rows'' setting, or the ``li#''
4976 setting from the termcap entry matching the environment
4979 width N: This integer value is the number of characters on a line.
4980 Default is 80, the current `stty cols'' setting, or the ``co#''
4981 setting from the termcap entry matching the environment
4984 Note: ``set screensize'' is obsolete. Use ``set height'' and
4985 ``set width'' instead.
4987 print address on/off: Print memory addresses in various command displays,
4988 such as stack traces and structure values. Gdb looks
4989 more ``symbolic'' if you turn this off; it looks more
4990 ``machine level'' with it on. Default is ON.
4992 print array on/off: Prettyprint arrays. New convenient format! Default
4995 print demangle on/off: Print C++ symbols in "source" form if on,
4998 print asm-demangle on/off: Same, for assembler level printouts
5001 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
5004 * Support for Epoch Environment.
5006 The epoch environment is a version of Emacs v18 with windowing. One
5007 new command, ``inspect'', is identical to ``print'', except that if you
5008 are running in the epoch environment, the value is printed in its own
5012 * Support for Shared Libraries
5014 GDB can now debug programs and core files that use SunOS shared libraries.
5015 Symbols from a shared library cannot be referenced
5016 before the shared library has been linked with the program (this
5017 happens after you type ``run'' and before the function main() is entered).
5018 At any time after this linking (including when examining core files
5019 from dynamically linked programs), gdb reads the symbols from each
5020 shared library when you type the ``sharedlibrary'' command.
5021 It can be abbreviated ``share''.
5023 sharedlibrary REGEXP: Load shared object library symbols for files
5024 matching a unix regular expression. No argument
5025 indicates to load symbols for all shared libraries.
5027 info sharedlibrary: Status of loaded shared libraries.
5032 A watchpoint stops execution of a program whenever the value of an
5033 expression changes. Checking for this slows down execution
5034 tremendously whenever you are in the scope of the expression, but is
5035 quite useful for catching tough ``bit-spreader'' or pointer misuse
5036 problems. Some machines such as the 386 have hardware for doing this
5037 more quickly, and future versions of gdb will use this hardware.
5039 watch EXP: Set a watchpoint (breakpoint) for an expression.
5041 info watchpoints: Information about your watchpoints.
5043 delete N: Deletes watchpoint number N (same as breakpoints).
5044 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5045 enable N: Re-enables watchpoint number N (same as breakpoints).
5048 * C++ multiple inheritance
5050 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5053 * C++ exception handling
5055 Gdb now supports limited C++ exception handling. Besides the existing
5056 ability to breakpoint on an exception handler, gdb can breakpoint on
5057 the raising of an exception (before the stack is peeled back to the
5060 catch FOO: If there is a FOO exception handler in the dynamic scope,
5061 set a breakpoint to catch exceptions which may be raised there.
5062 Multiple exceptions (``catch foo bar baz'') may be caught.
5064 info catch: Lists all exceptions which may be caught in the
5065 current stack frame.
5068 * Minor command changes
5070 The command ``call func (arg, arg, ...)'' now acts like the print
5071 command, except it does not print or save a value if the function's result
5072 is void. This is similar to dbx usage.
5074 The ``up'' and ``down'' commands now always print the frame they end up
5075 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5076 frames without printing.
5078 * New directory command
5080 'dir' now adds directories to the FRONT of the source search path.
5081 The path starts off empty. Source files that contain debug information
5082 about the directory in which they were compiled can be found even
5083 with an empty path; Sun CC and GCC include this information. If GDB can't
5084 find your source file in the current directory, type "dir .".
5086 * Configuring GDB for compilation
5088 For normal use, type ``./configure host''. See README or gdb.texinfo
5091 GDB now handles cross debugging. If you are remotely debugging between
5092 two different machines, type ``./configure host -target=targ''.
5093 Host is the machine where GDB will run; targ is the machine
5094 where the program that you are debugging will run.