1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
6 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
9 * GDB now supports access to MIPS DSP registers on Linux targets.
11 * GDB now supports debugging microMIPS binaries.
13 * The "info os" command on GNU/Linux can now display information on
14 several new classes of objects managed by the operating system:
15 "info os procgroups" lists process groups
16 "info os files" lists file descriptors
17 "info os sockets" lists internet-domain sockets
18 "info os shm" lists shared-memory regions
19 "info os semaphores" lists semaphores
20 "info os msg" lists message queues
21 "info os modules" lists loaded kernel modules
23 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
24 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
25 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
26 options and inspect the probe arguments using the new $_probe_arg family
27 of convenience variables. You can obtain more information about SystemTap
28 in <http://sourceware.org/systemtap/>.
30 * GDB now supports reversible debugging on ARM, it allows you to
31 debug basic ARM and THUMB instructions, and provides
32 record/replay support.
34 * The option "symbol-reloading" has been deleted as it is no longer used.
38 ** GDB commands implemented in Python can now be put in command class
41 ** The "maint set python print-stack on|off" is now deleted.
43 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
44 apply "flag enum"-style pretty-printing to any enum.
46 ** gdb.lookup_symbol can now work when there is no current frame.
48 ** gdb.Symbol now has a 'line' attribute, holding the line number in
49 the source at which the symbol was defined.
51 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
52 method 'value'. The former indicates whether the symbol needs a
53 frame in order to compute its value, and the latter computes the
56 ** A new method 'referenced_value' on gdb.Value objects which can
57 dereference pointer as well as C++ reference values.
59 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
60 which return the global and static blocks (as gdb.Block objects),
61 of the underlying symbol table, respectively.
63 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
64 object associated with a PC value.
66 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
67 of the address range occupied by code for the current source line.
69 * Go language support.
70 GDB now supports debugging programs written in the Go programming
73 * GDBserver now supports stdio connections.
74 E.g. (gdb) target remote | ssh myhost gdbserver - hello
76 * The binary "gdbtui" can no longer be built or installed.
77 Use "gdb -tui" instead.
79 * GDB will now print "flag" enums specially. A flag enum is one where
80 all the enumerator values have no bits in common when pairwise
81 "and"ed. When printing a value whose type is a flag enum, GDB will
82 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
83 (gdb) print (enum E) 3
86 * The filename part of a linespec will now match trailing components
87 of a source file name. For example, "break gcc/expr.c:1000" will
88 now set a breakpoint in build/gcc/expr.c, but not
91 * The "info proc" and "generate-core-file" commands will now also
92 work on remote targets connected to GDBserver on Linux.
94 * The command "info catch" has been removed. It has been disabled
97 * The "catch exception" and "catch assert" commands now accept
98 a condition at the end of the command, much like the "break"
99 command does. For instance:
101 (gdb) catch exception Constraint_Error if Barrier = True
103 Previously, it was possible to add a condition to such catchpoints,
104 but it had to be done as a second step, after the catchpoint had been
105 created, using the "condition" command.
107 * The "info static-tracepoint-marker" command will now also work on
108 native Linux targets with in-process agent.
110 * GDB can now set breakpoints on inlined functions.
112 * The .gdb_index section has been updated to include symbols for
113 inlined functions. GDB will ignore older .gdb_index sections by
114 default, which could cause symbol files to be loaded more slowly
115 until their .gdb_index sections can be recreated. The new option
116 --use-deprecated-index-sections will cause GDB to use any older
117 .gdb_index sections it finds. This will restore performance, but
118 the ability to set breakpoints on inlined functions will be lost
119 in symbol files with older .gdb_index sections.
121 The .gdb_index section has also been updated to record more information
122 about each symbol. This speeds up the "info variables", "info functions"
123 and "info types" commands when used with programs having the .gdb_index
124 section, as well as speeding up debugging with shared libraries using
125 the .gdb_index section.
127 * Ada support for GDB/MI Variable Objects has been added.
129 * GDB can now support 'breakpoint always-inserted mode' in 'record'
134 ** New command -info-os is the MI equivalent of "info os".
136 ** Output logs ("set logging" and related) now include MI output.
140 ** "catch load" and "catch unload" can be used to stop when a shared
141 library is loaded or unloaded, respectively.
143 ** "enable count" can be used to auto-disable a breakpoint after
146 ** "info vtbl" can be used to show the virtual method tables for
147 C++ and Java objects.
149 ** "explore" and its sub commands "explore value" and "explore type"
150 can be used to reccursively explore values and types of
151 expressions. These commands are available only if GDB is
152 configured with '--with-python'.
154 ** "info auto-load" shows status of all kinds of auto-loaded files,
155 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
156 sequences of commands files, "info auto-load python-scripts"
157 shows status of auto-loading Python script files,
158 "info auto-load local-gdbinit" shows status of loading init file
159 (.gdbinit) from current directory and "info auto-load libthread-db" shows
160 status of inferior specific thread debugging shared library loading.
162 ** "info auto-load-scripts", "set auto-load-scripts on|off"
163 and "show auto-load-scripts" commands have been deprecated, use their
164 "info auto-load python-scripts", "set auto-load python-scripts on|off"
165 and "show auto-load python-scripts" counterparts instead.
167 ** "dprintf location,format,args..." creates a dynamic printf, which
168 is basically a breakpoint that does a printf and immediately
169 resumes your program's execution, so it is like a printf that you
170 can insert dynamically at runtime instead of at compiletime.
172 ** "set print symbol"
174 Controls whether GDB attempts to display the symbol, if any,
175 corresponding to addresses it prints. This defaults to "on", but
176 you can set it to "off" to restore GDB's previous behavior.
178 * Deprecated commands
180 ** For the Renesas Super-H architecture, the "regs" command has been
181 deprecated, and "info all-registers" should be used instead.
185 Renesas RL78 rl78-*-elf
186 HP OpenVMS ia64 ia64-hp-openvms*
188 * GDBserver supports evaluation of breakpoint conditions. When
189 support is advertised by GDBserver, GDB may be told to send the
190 breakpoint conditions in bytecode form to GDBserver. GDBserver
191 will only report the breakpoint trigger to GDB when its condition
197 show mips compression
198 Select the compressed ISA encoding used in functions that have no symbol
199 information available. The encoding can be set to either of:
202 and is updated automatically from ELF file flags if available.
204 set breakpoint condition-evaluation
205 show breakpoint condition-evaluation
206 Control whether breakpoint conditions are evaluated by GDB ("host") or by
207 GDBserver ("target"). Default option "auto" chooses the most efficient
209 This option can improve debugger efficiency depending on the speed of the
213 Disable auto-loading globally.
216 Show auto-loading setting of all kinds of auto-loaded files.
218 set auto-load gdb-scripts on|off
219 show auto-load gdb-scripts
220 Control auto-loading of GDB canned sequences of commands files.
222 set auto-load python-scripts on|off
223 show auto-load python-scripts
224 Control auto-loading of Python script files.
226 set auto-load local-gdbinit on|off
227 show auto-load local-gdbinit
228 Control loading of init file (.gdbinit) from current directory.
230 set auto-load libthread-db on|off
231 show auto-load libthread-db
232 Control auto-loading of inferior specific thread debugging shared library.
234 set auto-load scripts-directory <dir1>[:<dir2>...]
235 show auto-load scripts-directory
236 Set a list of directories from which to load auto-loaded scripts.
237 Automatically loaded Python scripts and GDB scripts are located in one
238 of the directories listed by this option.
239 The delimiter (':' above) may differ according to the host platform.
241 set auto-load safe-path <dir1>[:<dir2>...]
242 show auto-load safe-path
243 Set a list of directories from which it is safe to auto-load files.
244 The delimiter (':' above) may differ according to the host platform.
246 set debug auto-load on|off
248 Control display of debugging info for auto-loading the files above.
250 set dprintf-style gdb|call|agent
252 Control the way in which a dynamic printf is performed; "gdb"
253 requests a GDB printf command, while "call" causes dprintf to call a
254 function in the inferior. "agent" requests that the target agent
255 (such as GDBserver) do the printing.
257 set dprintf-function <expr>
258 show dprintf-function
259 set dprintf-channel <expr>
261 Set the function and optional first argument to the call when using
262 the "call" style of dynamic printf.
264 set disconnected-dprintf on|off
265 show disconnected-dprintf
266 Control whether agent-style dynamic printfs continue to be in effect
267 after GDB disconnects.
269 * New configure options
272 Configure default value for the 'set auto-load scripts-directory'
273 setting above. It defaults to '$debugdir:$datadir/auto-load',
274 $debugdir representing global debugging info directories (available
275 via 'show debug-file-directory') and $datadir representing GDB's data
276 directory (available via 'show data-directory').
278 --with-auto-load-safe-path
279 Configure default value for the 'set auto-load safe-path' setting
280 above. It defaults to the --with-auto-load-dir setting.
282 --without-auto-load-safe-path
283 Set 'set auto-load safe-path' to '/', effectively disabling this
288 z0/z1 conditional breakpoints extension
290 The z0/z1 breakpoint insertion packets have been extended to carry
291 a list of conditional expressions over to the remote stub depending on the
292 condition evaluation mode. The use of this extension can be controlled
293 via the "set remote conditional-breakpoints-packet" command.
297 Specify the signals which the remote stub may pass to the debugged
298 program without GDB involvement.
300 * New command line options
302 --init-command=FILE, -ix Like --command, -x but execute it
303 before loading inferior.
304 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
305 execute it before loading inferior.
307 *** Changes in GDB 7.4
309 * GDB now handles ambiguous linespecs more consistently; the existing
310 FILE:LINE support has been expanded to other types of linespecs. A
311 breakpoint will now be set on all matching locations in all
312 inferiors, and locations will be added or removed according to
315 * GDB now allows you to skip uninteresting functions and files when
316 stepping with the "skip function" and "skip file" commands.
318 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
319 and "show remote hardware-watchpoint-length-limit". These allows to
320 set or show the maximum length limit (in bytes) of a remote
321 target hardware watchpoint.
323 This allows e.g. to use "unlimited" hardware watchpoints with the
324 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
325 watchpoints are slower than real hardware watchpoints but are
326 significantly faster than gdb software watchpoints.
330 ** The register_pretty_printer function in module gdb.printing now takes
331 an optional `replace' argument. If True, the new printer replaces any
334 ** The "maint set python print-stack on|off" command has been
335 deprecated and will be deleted in GDB 7.5.
336 A new command: "set python print-stack none|full|message" has
337 replaced it. Additionally, the default for "print-stack" is
338 now "message", which just prints the error message without
341 ** A prompt substitution hook (prompt_hook) is now available to the
344 ** A new Python module, gdb.prompt has been added to the GDB Python
345 modules library. This module provides functionality for
346 escape sequences in prompts (used by set/show
347 extended-prompt). These escape sequences are replaced by their
350 ** Python commands and convenience-functions located in
351 'data-directory'/python/gdb/command and
352 'data-directory'/python/gdb/function are now automatically loaded
355 ** Blocks now provide four new attributes. global_block and
356 static_block will return the global and static blocks
357 respectively. is_static and is_global are boolean attributes
358 that indicate if the block is one of those two types.
360 ** Symbols now provide the "type" attribute, the type of the symbol.
362 ** The "gdb.breakpoint" function has been deprecated in favor of
365 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
366 of a function. This class is based on the "finish" command
367 available in the CLI.
369 ** Type objects for struct and union types now allow access to
370 the fields using standard Python dictionary (mapping) methods.
371 For example, "some_type['myfield']" now works, as does
374 ** A new event "gdb.new_objfile" has been added, triggered by loading a
377 ** A new function, "deep_items" has been added to the gdb.types
378 module in the GDB Python modules library. This function returns
379 an iterator over the fields of a struct or union type. Unlike
380 the standard Python "iteritems" method, it will recursively traverse
381 any anonymous fields.
385 ** "*stopped" events can report several new "reason"s, such as
388 ** Breakpoint changes are now notified using new async records, like
389 "=breakpoint-modified".
391 ** New command -ada-task-info.
393 * libthread-db-search-path now supports two special values: $sdir and $pdir.
394 $sdir specifies the default system locations of shared libraries.
395 $pdir specifies the directory where the libpthread used by the application
398 GDB no longer looks in $sdir and $pdir after it has searched the directories
399 mentioned in libthread-db-search-path. If you want to search those
400 directories, they must be specified in libthread-db-search-path.
401 The default value of libthread-db-search-path on GNU/Linux and Solaris
402 systems is now "$sdir:$pdir".
404 $pdir is not supported by gdbserver, it is currently ignored.
405 $sdir is supported by gdbserver.
407 * New configure option --with-iconv-bin.
408 When using the internationalization support like the one in the GNU C
409 library, GDB will invoke the "iconv" program to get a list of supported
410 character sets. If this program lives in a non-standard location, one can
411 use this option to specify where to find it.
413 * When natively debugging programs on PowerPC BookE processors running
414 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
415 watchpoints, which specify a mask in addition to an address to watch.
416 The mask specifies that some bits of an address (the bits which are
417 reset in the mask) should be ignored when matching the address accessed
418 by the inferior against the watchpoint address. See the "PowerPC Embedded"
419 section in the user manual for more details.
421 * The new option --once causes GDBserver to stop listening for connections once
422 the first connection is made. The listening port used by GDBserver will
423 become available after that.
425 * New commands "info macros" and "alias" have been added.
427 * New function parameters suffix @entry specifies value of function parameter
428 at the time the function got called. Entry values are available only since
434 "!" is now an alias of the "shell" command.
435 Note that no space is needed between "!" and SHELL COMMAND.
439 watch EXPRESSION mask MASK_VALUE
440 The watch command now supports the mask argument which allows creation
441 of masked watchpoints, if the current architecture supports this feature.
443 info auto-load-scripts [REGEXP]
444 This command was formerly named "maintenance print section-scripts".
445 It is now generally useful and is no longer a maintenance-only command.
447 info macro [-all] [--] MACRO
448 The info macro command has new options `-all' and `--'. The first for
449 printing all definitions of a macro. The second for explicitly specifying
450 the end of arguments and the beginning of the macro name in case the macro
451 name starts with a hyphen.
453 collect[/s] EXPRESSIONS
454 The tracepoint collect command now takes an optional modifier "/s"
455 that directs it to dereference pointer-to-character types and
456 collect the bytes of memory up to a zero byte. The behavior is
457 similar to what you see when you use the regular print command on a
458 string. An optional integer following the "/s" sets a bound on the
459 number of bytes that will be collected.
462 The trace start command now interprets any supplied arguments as a
463 note to be recorded with the trace run, with an effect similar to
464 setting the variable trace-notes.
467 The trace stop command now interprets any arguments as a note to be
468 mentioned along with the tstatus report that the trace was stopped
469 with a command. The effect is similar to setting the variable
472 * Tracepoints can now be enabled and disabled at any time after a trace
473 experiment has been started using the standard "enable" and "disable"
474 commands. It is now possible to start a trace experiment with no enabled
475 tracepoints; GDB will display a warning, but will allow the experiment to
476 begin, assuming that tracepoints will be enabled as needed while the trace
479 * Fast tracepoints on 32-bit x86-architectures can now be placed at
480 locations with 4-byte instructions, when they were previously
481 limited to locations with instructions of 5 bytes or longer.
485 set debug dwarf2-read
486 show debug dwarf2-read
487 Turns on or off display of debugging messages related to reading
488 DWARF debug info. The default is off.
490 set debug symtab-create
491 show debug symtab-create
492 Turns on or off display of debugging messages related to symbol table
493 creation. The default is off.
497 Set the GDB prompt, and allow escape sequences to be inserted to
498 display miscellaneous information (see 'help set extended-prompt'
499 for the list of sequences). This prompt (and any information
500 accessed through the escape sequences) is updated every time the
503 set print entry-values (both|compact|default|if-needed|no|only|preferred)
504 show print entry-values
505 Set printing of frame argument values at function entry. In some cases
506 GDB can determine the value of function argument which was passed by the
507 function caller, even if the value was modified inside the called function.
509 set debug entry-values
510 show debug entry-values
511 Control display of debugging info for determining frame argument values at
512 function entry and virtual tail call frames.
514 set basenames-may-differ
515 show basenames-may-differ
516 Set whether a source file may have multiple base names.
517 (A "base name" is the name of a file with the directory part removed.
518 Example: The base name of "/home/user/hello.c" is "hello.c".)
519 If set, GDB will canonicalize file names (e.g., expand symlinks)
520 before comparing them. Canonicalization is an expensive operation,
521 but it allows the same file be known by more than one base name.
522 If not set (the default), all source files are assumed to have just
523 one base name, and gdb will do file name comparisons more efficiently.
529 Set a user name and notes for the current and any future trace runs.
530 This is useful for long-running and/or disconnected traces, to
531 inform others (or yourself) as to who is running the trace, supply
532 contact information, or otherwise explain what is going on.
535 show trace-stop-notes
536 Set a note attached to the trace run, that is displayed when the
537 trace has been stopped by a tstop command. This is useful for
538 instance as an explanation, if you are stopping a trace run that was
539 started by someone else.
545 Dynamically enable a tracepoint in a started trace experiment.
549 Dynamically disable a tracepoint in a started trace experiment.
553 Set the user and notes of the trace run.
557 Query the current status of a tracepoint.
561 Query the minimum length of instruction at which a fast tracepoint may
564 * Dcache size (number of lines) and line-size are now runtime-configurable
565 via "set dcache line" and "set dcache line-size" commands.
569 Texas Instruments TMS320C6x tic6x-*-*
573 Renesas RL78 rl78-*-elf
575 *** Changes in GDB 7.3.1
577 * The build failure for NetBSD and OpenBSD targets have now been fixed.
579 *** Changes in GDB 7.3
581 * GDB has a new command: "thread find [REGEXP]".
582 It finds the thread id whose name, target id, or thread extra info
583 matches the given regular expression.
585 * The "catch syscall" command now works on mips*-linux* targets.
587 * The -data-disassemble MI command now supports modes 2 and 3 for
588 dumping the instruction opcodes.
590 * New command line options
592 -data-directory DIR Specify DIR as the "data-directory".
593 This is mostly for testing purposes.
595 * The "maint set python auto-load on|off" command has been renamed to
596 "set auto-load-scripts on|off".
598 * GDB has a new command: "set directories".
599 It is like the "dir" command except that it replaces the
600 source path list instead of augmenting it.
602 * GDB now understands thread names.
604 On GNU/Linux, "info threads" will display the thread name as set by
605 prctl or pthread_setname_np.
607 There is also a new command, "thread name", which can be used to
608 assign a name internally for GDB to display.
611 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
612 has been integrated into GDB.
616 ** The function gdb.Write now accepts an optional keyword 'stream'.
617 This keyword, when provided, will direct the output to either
618 stdout, stderr, or GDB's logging output.
620 ** Parameters can now be be sub-classed in Python, and in particular
621 you may implement the get_set_doc and get_show_doc functions.
622 This improves how Parameter set/show documentation is processed
623 and allows for more dynamic content.
625 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
626 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
627 have an is_valid method.
629 ** Breakpoints can now be sub-classed in Python, and in particular
630 you may implement a 'stop' function that is executed each time
631 the inferior reaches that breakpoint.
633 ** New function gdb.lookup_global_symbol looks up a global symbol.
635 ** GDB values in Python are now callable if the value represents a
636 function. For example, if 'some_value' represents a function that
637 takes two integer parameters and returns a value, you can call
638 that function like so:
640 result = some_value (10,20)
642 ** Module gdb.types has been added.
643 It contains a collection of utilities for working with gdb.Types objects:
644 get_basic_type, has_field, make_enum_dict.
646 ** Module gdb.printing has been added.
647 It contains utilities for writing and registering pretty-printers.
648 New classes: PrettyPrinter, SubPrettyPrinter,
649 RegexpCollectionPrettyPrinter.
650 New function: register_pretty_printer.
652 ** New commands "info pretty-printers", "enable pretty-printer" and
653 "disable pretty-printer" have been added.
655 ** gdb.parameter("directories") is now available.
657 ** New function gdb.newest_frame returns the newest frame in the
660 ** The gdb.InferiorThread class has a new "name" attribute. This
661 holds the thread's name.
663 ** Python Support for Inferior events.
664 Python scripts can add observers to be notified of events
665 occurring in the process being debugged.
666 The following events are currently supported:
667 - gdb.events.cont Continue event.
668 - gdb.events.exited Inferior exited event.
669 - gdb.events.stop Signal received, and Breakpoint hit events.
673 ** GDB now puts template parameters in scope when debugging in an
674 instantiation. For example, if you have:
676 template<int X> int func (void) { return X; }
678 then if you step into func<5>, "print X" will show "5". This
679 feature requires proper debuginfo support from the compiler; it
680 was added to GCC 4.5.
682 ** The motion commands "next", "finish", "until", and "advance" now
683 work better when exceptions are thrown. In particular, GDB will
684 no longer lose control of the inferior; instead, the GDB will
685 stop the inferior at the point at which the exception is caught.
686 This functionality requires a change in the exception handling
687 code that was introduced in GCC 4.5.
689 * GDB now follows GCC's rules on accessing volatile objects when
690 reading or writing target state during expression evaluation.
691 One notable difference to prior behavior is that "print x = 0"
692 no longer generates a read of x; the value of the assignment is
693 now always taken directly from the value being assigned.
695 * GDB now has some support for using labels in the program's source in
696 linespecs. For instance, you can use "advance label" to continue
697 execution to a label.
699 * GDB now has support for reading and writing a new .gdb_index
700 section. This section holds a fast index of DWARF debugging
701 information and can be used to greatly speed up GDB startup and
702 operation. See the documentation for `save gdb-index' for details.
704 * The "watch" command now accepts an optional "-location" argument.
705 When used, this causes GDB to watch the memory referred to by the
706 expression. Such a watchpoint is never deleted due to it going out
709 * GDB now supports thread debugging of core dumps on GNU/Linux.
711 GDB now activates thread debugging using the libthread_db library
712 when debugging GNU/Linux core dumps, similarly to when debugging
713 live processes. As a result, when debugging a core dump file, GDB
714 is now able to display pthread_t ids of threads. For example, "info
715 threads" shows the same output as when debugging the process when it
716 was live. In earlier releases, you'd see something like this:
719 * 1 LWP 6780 main () at main.c:10
721 While now you see this:
724 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
726 It is also now possible to inspect TLS variables when debugging core
729 When debugging a core dump generated on a machine other than the one
730 used to run GDB, you may need to point GDB at the correct
731 libthread_db library with the "set libthread-db-search-path"
732 command. See the user manual for more details on this command.
734 * When natively debugging programs on PowerPC BookE processors running
735 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
736 which stop execution of the inferior whenever it executes an instruction
737 at any address within the specified range. See the "PowerPC Embedded"
738 section in the user manual for more details.
740 * New features in the GDB remote stub, GDBserver
742 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
743 and i686 LynxOS (version 5.x).
745 ** GDBserver is now supported on Blackfin Linux.
747 * New native configurations
749 ia64 HP-UX ia64-*-hpux*
753 Analog Devices, Inc. Blackfin Processor bfin-*
755 * Ada task switching is now supported on sparc-elf targets when
756 debugging a program using the Ravenscar Profile. For more information,
757 see the "Tasking Support when using the Ravenscar Profile" section
758 in the GDB user manual.
760 * Guile support was removed.
762 * New features in the GNU simulator
764 ** The --map-info flag lists all known core mappings.
766 ** CFI flashes may be simulated via the "cfi" device.
768 *** Changes in GDB 7.2
770 * Shared library support for remote targets by default
772 When GDB is configured for a generic, non-OS specific target, like
773 for example, --target=arm-eabi or one of the many *-*-elf targets,
774 GDB now queries remote stubs for loaded shared libraries using the
775 `qXfer:libraries:read' packet. Previously, shared library support
776 was always disabled for such configurations.
780 ** Argument Dependent Lookup (ADL)
782 In C++ ADL lookup directs function search to the namespaces of its
783 arguments even if the namespace has not been imported.
793 Here the compiler will search for `foo' in the namespace of 'b'
794 and find A::foo. GDB now supports this. This construct is commonly
795 used in the Standard Template Library for operators.
797 ** Improved User Defined Operator Support
799 In addition to member operators, GDB now supports lookup of operators
800 defined in a namespace and imported with a `using' directive, operators
801 defined in the global scope, operators imported implicitly from an
802 anonymous namespace, and the ADL operators mentioned in the previous
804 GDB now also supports proper overload resolution for all the previously
805 mentioned flavors of operators.
807 ** static const class members
809 Printing of static const class members that are initialized in the
810 class definition has been fixed.
812 * Windows Thread Information Block access.
814 On Windows targets, GDB now supports displaying the Windows Thread
815 Information Block (TIB) structure. This structure is visible either
816 by using the new command `info w32 thread-information-block' or, by
817 dereferencing the new convenience variable named `$_tlb', a
818 thread-specific pointer to the TIB. This feature is also supported
819 when remote debugging using GDBserver.
823 Static tracepoints are calls in the user program into a tracing
824 library. One such library is a port of the LTTng kernel tracer to
825 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
826 When debugging with GDBserver, GDB now supports combining the GDB
827 tracepoint machinery with such libraries. For example: the user can
828 use GDB to probe a static tracepoint marker (a call from the user
829 program into the tracing library) with the new "strace" command (see
830 "New commands" below). This creates a "static tracepoint" in the
831 breakpoint list, that can be manipulated with the same feature set
832 as fast and regular tracepoints. E.g., collect registers, local and
833 global variables, collect trace state variables, and define
834 tracepoint conditions. In addition, the user can collect extra
835 static tracepoint marker specific data, by collecting the new
836 $_sdata internal variable. When analyzing the trace buffer, you can
837 inspect $_sdata like any other variable available to GDB. For more
838 information, see the "Tracepoints" chapter in GDB user manual. New
839 remote packets have been defined to support static tracepoints, see
840 the "New remote packets" section below.
842 * Better reconstruction of tracepoints after disconnected tracing
844 GDB will attempt to download the original source form of tracepoint
845 definitions when starting a trace run, and then will upload these
846 upon reconnection to the target, resulting in a more accurate
847 reconstruction of the tracepoints that are in use on the target.
851 You can now exercise direct control over the ways that GDB can
852 affect your program. For instance, you can disallow the setting of
853 breakpoints, so that the program can run continuously (assuming
854 non-stop mode). In addition, the "observer" variable is available
855 to switch all of the different controls; in observer mode, GDB
856 cannot affect the target's behavior at all, which is useful for
857 tasks like diagnosing live systems in the field.
859 * The new convenience variable $_thread holds the number of the
866 Return the address of the Windows Thread Information Block of a given thread.
870 In response to several of the tracepoint packets, the target may now
871 also respond with a number of intermediate `qRelocInsn' request
872 packets before the final result packet, to have GDB handle
873 relocating an instruction to execute at a different address. This
874 is particularly useful for stubs that support fast tracepoints. GDB
875 reports support for this feature in the qSupported packet.
879 List static tracepoint markers in the target program.
883 List static tracepoint markers at a given address in the target
886 qXfer:statictrace:read
888 Read the static trace data collected (by a `collect $_sdata'
889 tracepoint action). The remote stub reports support for this packet
890 to gdb's qSupported query.
894 Send the current settings of GDB's permission flags.
898 Send part of the source (textual) form of a tracepoint definition,
899 which includes location, conditional, and action list.
901 * The source command now accepts a -s option to force searching for the
902 script in the source search path even if the script name specifies
905 * New features in the GDB remote stub, GDBserver
907 - GDBserver now support tracepoints (including fast tracepoints, and
908 static tracepoints). The feature is currently supported by the
909 i386-linux and amd64-linux builds. See the "Tracepoints support
910 in gdbserver" section in the manual for more information.
912 GDBserver JIT compiles the tracepoint's conditional agent
913 expression bytecode into native code whenever possible for low
914 overhead dynamic tracepoints conditionals. For such tracepoints,
915 an expression that examines program state is evaluated when the
916 tracepoint is reached, in order to determine whether to capture
917 trace data. If the condition is simple and false, processing the
918 tracepoint finishes very quickly and no data is gathered.
920 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
921 for static tracepoints support.
923 - GDBserver now supports x86_64 Windows 64-bit debugging.
925 * GDB now sends xmlRegisters= in qSupported packet to indicate that
926 it understands register description.
928 * The --batch flag now disables pagination and queries.
930 * X86 general purpose registers
932 GDB now supports reading/writing byte, word and double-word x86
933 general purpose registers directly. This means you can use, say,
934 $ah or $ax to refer, respectively, to the byte register AH and
935 16-bit word register AX that are actually portions of the 32-bit
936 register EAX or 64-bit register RAX.
938 * The `commands' command now accepts a range of breakpoints to modify.
939 A plain `commands' following a command that creates multiple
940 breakpoints affects all the breakpoints set by that command. This
941 applies to breakpoints set by `rbreak', and also applies when a
942 single `break' command creates multiple breakpoints (e.g.,
943 breakpoints on overloaded c++ functions).
945 * The `rbreak' command now accepts a filename specification as part of
946 its argument, limiting the functions selected by the regex to those
947 in the specified file.
949 * Support for remote debugging Windows and SymbianOS shared libraries
950 from Unix hosts has been improved. Non Windows GDB builds now can
951 understand target reported file names that follow MS-DOS based file
952 system semantics, such as file names that include drive letters and
953 use the backslash character as directory separator. This makes it
954 possible to transparently use the "set sysroot" and "set
955 solib-search-path" on Unix hosts to point as host copies of the
956 target's shared libraries. See the new command "set
957 target-file-system-kind" described below, and the "Commands to
958 specify files" section in the user manual for more information.
962 eval template, expressions...
963 Convert the values of one or more expressions under the control
964 of the string template to a command line, and call it.
966 set target-file-system-kind unix|dos-based|auto
967 show target-file-system-kind
968 Set or show the assumed file system kind for target reported file
971 save breakpoints <filename>
972 Save all current breakpoint definitions to a file suitable for use
973 in a later debugging session. To read the saved breakpoint
974 definitions, use the `source' command.
976 `save tracepoints' is a new alias for `save-tracepoints'. The latter
979 info static-tracepoint-markers
980 Display information about static tracepoint markers in the target.
982 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
983 Define a static tracepoint by probing a marker at the given
984 function, line, address, or marker ID.
988 Enable and disable observer mode.
990 set may-write-registers on|off
991 set may-write-memory on|off
992 set may-insert-breakpoints on|off
993 set may-insert-tracepoints on|off
994 set may-insert-fast-tracepoints on|off
995 set may-interrupt on|off
996 Set individual permissions for GDB effects on the target. Note that
997 some of these settings can have undesirable or surprising
998 consequences, particularly when changed in the middle of a session.
999 For instance, disabling the writing of memory can prevent
1000 breakpoints from being inserted, cause single-stepping to fail, or
1001 even crash your program, if you disable after breakpoints have been
1002 inserted. However, GDB should not crash.
1004 set record memory-query on|off
1005 show record memory-query
1006 Control whether to stop the inferior if memory changes caused
1007 by an instruction cannot be recorded.
1012 The disassemble command now supports "start,+length" form of two arguments.
1016 ** GDB now provides a new directory location, called the python directory,
1017 where Python scripts written for GDB can be installed. The location
1018 of that directory is <data-directory>/python, where <data-directory>
1019 is the GDB data directory. For more details, see section `Scripting
1020 GDB using Python' in the manual.
1022 ** The GDB Python API now has access to breakpoints, symbols, symbol
1023 tables, program spaces, inferiors, threads and frame's code blocks.
1024 Additionally, GDB Parameters can now be created from the API, and
1025 manipulated via set/show in the CLI.
1027 ** New functions gdb.target_charset, gdb.target_wide_charset,
1028 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
1030 ** New exception gdb.GdbError.
1032 ** Pretty-printers are now also looked up in the current program space.
1034 ** Pretty-printers can now be individually enabled and disabled.
1036 ** GDB now looks for names of Python scripts to auto-load in a
1037 special section named `.debug_gdb_scripts', in addition to looking
1038 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
1040 * Tracepoint actions were unified with breakpoint commands. In particular,
1041 there are no longer differences in "info break" output for breakpoints and
1042 tracepoints and the "commands" command can be used for both tracepoints and
1043 regular breakpoints.
1047 ARM Symbian arm*-*-symbianelf*
1049 * D language support.
1050 GDB now supports debugging programs written in the D programming
1053 * GDB now supports the extended ptrace interface for PowerPC which is
1054 available since Linux kernel version 2.6.34. This automatically enables
1055 any hardware breakpoints and additional hardware watchpoints available in
1056 the processor. The old ptrace interface exposes just one hardware
1057 watchpoint and no hardware breakpoints.
1059 * GDB is now able to use the Data Value Compare (DVC) register available on
1060 embedded PowerPC processors to implement in hardware simple watchpoint
1061 conditions of the form:
1063 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
1065 This works in native GDB running on Linux kernels with the extended ptrace
1066 interface mentioned above.
1068 *** Changes in GDB 7.1
1072 ** Namespace Support
1074 GDB now supports importing of namespaces in C++. This enables the
1075 user to inspect variables from imported namespaces. Support for
1076 namepace aliasing has also been added. So, if a namespace is
1077 aliased in the current scope (e.g. namepace C=A; ) the user can
1078 print variables using the alias (e.g. (gdb) print C::x).
1082 All known bugs relating to the printing of virtual base class were
1083 fixed. It is now possible to call overloaded static methods using a
1088 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
1089 and reinterpret_cast<> are now handled by the C++ expression parser.
1093 Xilinx MicroBlaze microblaze-*-*
1098 Xilinx MicroBlaze microblaze
1101 * Multi-program debugging.
1103 GDB now has support for multi-program (a.k.a. multi-executable or
1104 multi-exec) debugging. This allows for debugging multiple inferiors
1105 simultaneously each running a different program under the same GDB
1106 session. See "Debugging Multiple Inferiors and Programs" in the
1107 manual for more information. This implied some user visible changes
1108 in the multi-inferior support. For example, "info inferiors" now
1109 lists inferiors that are not running yet or that have exited
1110 already. See also "New commands" and "New options" below.
1112 * New tracing features
1114 GDB's tracepoint facility now includes several new features:
1116 ** Trace state variables
1118 GDB tracepoints now include support for trace state variables, which
1119 are variables managed by the target agent during a tracing
1120 experiment. They are useful for tracepoints that trigger each
1121 other, so for instance one tracepoint can count hits in a variable,
1122 and then a second tracepoint has a condition that is true when the
1123 count reaches a particular value. Trace state variables share the
1124 $-syntax of GDB convenience variables, and can appear in both
1125 tracepoint actions and condition expressions. Use the "tvariable"
1126 command to create, and "info tvariables" to view; see "Trace State
1127 Variables" in the manual for more detail.
1131 GDB now includes an option for defining fast tracepoints, which
1132 targets may implement more efficiently, such as by installing a jump
1133 into the target agent rather than a trap instruction. The resulting
1134 speedup can be by two orders of magnitude or more, although the
1135 tradeoff is that some program locations on some target architectures
1136 might not allow fast tracepoint installation, for instance if the
1137 instruction to be replaced is shorter than the jump. To request a
1138 fast tracepoint, use the "ftrace" command, with syntax identical to
1139 the regular trace command.
1141 ** Disconnected tracing
1143 It is now possible to detach GDB from the target while it is running
1144 a trace experiment, then reconnect later to see how the experiment
1145 is going. In addition, a new variable disconnected-tracing lets you
1146 tell the target agent whether to continue running a trace if the
1147 connection is lost unexpectedly.
1151 GDB now has the ability to save the trace buffer into a file, and
1152 then use that file as a target, similarly to you can do with
1153 corefiles. You can select trace frames, print data that was
1154 collected in them, and use tstatus to display the state of the
1155 tracing run at the moment that it was saved. To create a trace
1156 file, use "tsave <filename>", and to use it, do "target tfile
1159 ** Circular trace buffer
1161 You can ask the target agent to handle the trace buffer as a
1162 circular buffer, discarding the oldest trace frames to make room for
1163 newer ones, by setting circular-trace-buffer to on. This feature may
1164 not be available for all target agents.
1169 The disassemble command, when invoked with two arguments, now requires
1170 the arguments to be comma-separated.
1173 The info variables command now displays variable definitions. Files
1174 which only declare a variable are not shown.
1177 The source command is now capable of sourcing Python scripts.
1178 This feature is dependent on the debugger being build with Python
1181 Related to this enhancement is also the introduction of a new command
1182 "set script-extension" (see below).
1184 * New commands (for set/show, see "New options" below)
1186 record save [<FILENAME>]
1187 Save a file (in core file format) containing the process record
1188 execution log for replay debugging at a later time.
1190 record restore <FILENAME>
1191 Restore the process record execution log that was saved at an
1192 earlier time, for replay debugging.
1194 add-inferior [-copies <N>] [-exec <FILENAME>]
1197 clone-inferior [-copies <N>] [ID]
1198 Make a new inferior ready to execute the same program another
1199 inferior has loaded.
1204 maint info program-spaces
1205 List the program spaces loaded into GDB.
1207 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
1208 show remote interrupt-sequence
1209 Allow the user to select one of ^C, a BREAK signal or BREAK-g
1210 as the sequence to the remote target in order to interrupt the execution.
1211 Ctrl-C is a default. Some system prefers BREAK which is high level of
1212 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
1213 Magic SysRq g. It is BREAK signal and character 'g'.
1215 set remote interrupt-on-connect [on | off]
1216 show remote interrupt-on-connect
1217 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
1218 remote target when gdb connects to it. This is needed when you debug
1221 set remotebreak [on | off]
1223 Deprecated. Use "set/show remote interrupt-sequence" instead.
1225 tvariable $NAME [ = EXP ]
1226 Create or modify a trace state variable.
1229 List trace state variables and their values.
1231 delete tvariable $NAME ...
1232 Delete one or more trace state variables.
1235 Evaluate the given expressions without collecting anything into the
1236 trace buffer. (Valid in tracepoint actions only.)
1238 ftrace FN / FILE:LINE / *ADDR
1239 Define a fast tracepoint at the given function, line, or address.
1241 * New expression syntax
1243 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
1244 GDB now parses 0b101010 identically with 42.
1248 set follow-exec-mode new|same
1249 show follow-exec-mode
1250 Control whether GDB reuses the same inferior across an exec call or
1251 creates a new one. This is useful to be able to restart the old
1252 executable after the inferior having done an exec call.
1254 set default-collect EXPR, ...
1255 show default-collect
1256 Define a list of expressions to be collected at each tracepoint.
1257 This is a useful way to ensure essential items are not overlooked,
1258 such as registers or a critical global variable.
1260 set disconnected-tracing
1261 show disconnected-tracing
1262 If set to 1, the target is instructed to continue tracing if it
1263 loses its connection to GDB. If 0, the target is to stop tracing
1266 set circular-trace-buffer
1267 show circular-trace-buffer
1268 If set to on, the target is instructed to use a circular trace buffer
1269 and discard the oldest trace frames instead of stopping the trace due
1270 to a full trace buffer. If set to off, the trace stops when the buffer
1271 fills up. Some targets may not support this.
1273 set script-extension off|soft|strict
1274 show script-extension
1275 If set to "off", the debugger does not perform any script language
1276 recognition, and all sourced files are assumed to be GDB scripts.
1277 If set to "soft" (the default), files are sourced according to
1278 filename extension, falling back to GDB scripts if the first
1280 If set to "strict", files are sourced according to filename extension.
1282 set ada trust-PAD-over-XVS on|off
1283 show ada trust-PAD-over-XVS
1284 If off, activate a workaround against a bug in the debugging information
1285 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
1286 the GCC sources for more information about the GNAT encoding and
1287 PAD types in particular). It is always safe to set this option to
1288 off, but this introduces a slight performance penalty. The default
1291 * Python API Improvements
1293 ** GDB provides the new class gdb.LazyString. This is useful in
1294 some pretty-printing cases. The new method gdb.Value.lazy_string
1295 provides a simple way to create objects of this type.
1297 ** The fields returned by gdb.Type.fields now have an
1298 `is_base_class' attribute.
1300 ** The new method gdb.Type.range returns the range of an array type.
1302 ** The new method gdb.parse_and_eval can be used to parse and
1303 evaluate an expression.
1305 * New remote packets
1308 Define a trace state variable.
1311 Get the current value of a trace state variable.
1314 Set desired tracing behavior upon disconnection.
1317 Set the trace buffer to be linear or circular.
1320 Get data about the tracepoints currently in use.
1324 Process record now works correctly with hardware watchpoints.
1326 Multiple bug fixes have been made to the mips-irix port, making it
1327 much more reliable. In particular:
1328 - Debugging threaded applications is now possible again. Previously,
1329 GDB would hang while starting the program, or while waiting for
1330 the program to stop at a breakpoint.
1331 - Attaching to a running process no longer hangs.
1332 - An error occurring while loading a core file has been fixed.
1333 - Changing the value of the PC register now works again. This fixes
1334 problems observed when using the "jump" command, or when calling
1335 a function from GDB, or even when assigning a new value to $pc.
1336 - With the "finish" and "return" commands, the return value for functions
1337 returning a small array is now correctly printed.
1338 - It is now possible to break on shared library code which gets executed
1339 during a shared library init phase (code executed while executing
1340 their .init section). Previously, the breakpoint would have no effect.
1341 - GDB is now able to backtrace through the signal handler for
1342 non-threaded programs.
1344 PIE (Position Independent Executable) programs debugging is now supported.
1345 This includes debugging execution of PIC (Position Independent Code) shared
1346 libraries although for that, it should be possible to run such libraries as an
1349 *** Changes in GDB 7.0
1351 * GDB now has an interface for JIT compilation. Applications that
1352 dynamically generate code can create symbol files in memory and register
1353 them with GDB. For users, the feature should work transparently, and
1354 for JIT developers, the interface is documented in the GDB manual in the
1355 "JIT Compilation Interface" chapter.
1357 * Tracepoints may now be conditional. The syntax is as for
1358 breakpoints; either an "if" clause appended to the "trace" command,
1359 or the "condition" command is available. GDB sends the condition to
1360 the target for evaluation using the same bytecode format as is used
1361 for tracepoint actions.
1363 * The disassemble command now supports: an optional /r modifier, print the
1364 raw instructions in hex as well as in symbolic form, and an optional /m
1365 modifier to print mixed source+assembly.
1367 * Process record and replay
1369 In a architecture environment that supports ``process record and
1370 replay'', ``process record and replay'' target can record a log of
1371 the process execution, and replay it with both forward and reverse
1374 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1375 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1376 set execution-direction {forward|reverse}, for targets that support
1379 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1380 feature is available with a native GDB running on kernel version
1383 * GDB now has support for multi-byte and wide character sets on the
1384 target. Strings whose character type is wchar_t, char16_t, or
1385 char32_t are now correctly printed. GDB supports wide- and unicode-
1386 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1387 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1388 `printf'. This feature requires iconv to work properly; if your
1389 system does not have a working iconv, GDB can use GNU libiconv. See
1390 the installation instructions for more information.
1392 * GDB now supports automatic retrieval of shared library files from
1393 remote targets. To use this feature, specify a system root that begins
1394 with the `remote:' prefix, either via the `set sysroot' command or via
1395 the `--with-sysroot' configure-time option.
1397 * "info sharedlibrary" now takes an optional regex of libraries to show,
1398 and it now reports if a shared library has no debugging information.
1400 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1401 now complete on file names.
1403 * When completing in expressions, gdb will attempt to limit
1404 completions to allowable structure or union fields, where appropriate.
1405 For instance, consider:
1407 # struct example { int f1; double f2; };
1408 # struct example variable;
1411 If the user types TAB at the end of this command line, the available
1412 completions will be "f1" and "f2".
1414 * Inlined functions are now supported. They show up in backtraces, and
1415 the "step", "next", and "finish" commands handle them automatically.
1417 * GDB now supports the token-splicing (##) and stringification (#)
1418 operators when expanding macros. It also supports variable-arity
1421 * GDB now supports inspecting extra signal information, exported by
1422 the new $_siginfo convenience variable. The feature is currently
1423 implemented on linux ARM, i386 and amd64.
1425 * GDB can now display the VFP floating point registers and NEON vector
1426 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1427 can provide these registers (requires Linux 2.6.30 or later). Remote
1428 and simulator targets may also provide them.
1430 * New remote packets
1433 Search memory for a sequence of bytes.
1436 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1437 operation over reliable transport links. Use of this packet is
1438 controlled by the `set remote noack-packet' command.
1441 Kill the process with the specified process ID. Use this in preference
1442 to `k' when multiprocess protocol extensions are supported.
1445 Obtains additional operating system information
1449 Read or write additional signal information.
1451 * Removed remote protocol undocumented extension
1453 An undocumented extension to the remote protocol's `S' stop reply
1454 packet that permited the stub to pass a process id was removed.
1455 Remote servers should use the `T' stop reply packet instead.
1457 * GDB now supports multiple function calling conventions according to the
1458 DWARF-2 DW_AT_calling_convention function attribute.
1460 * The SH target utilizes the aforementioned change to distinguish between gcc
1461 and Renesas calling convention. It also adds the new CLI commands
1462 `set/show sh calling-convention'.
1464 * GDB can now read compressed debug sections, as produced by GNU gold
1465 with the --compress-debug-sections=zlib flag.
1467 * 64-bit core files are now supported on AIX.
1469 * Thread switching is now supported on Tru64.
1471 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1472 which will be allocated using malloc later in program execution.
1474 * The qXfer:libraries:read remote procotol packet now allows passing a
1475 list of section offsets.
1477 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1478 conditions handling signals delivered during attach or thread creation
1479 have also been fixed.
1481 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1482 From the user's standpoint, all unqualified instances of True and False
1483 are treated as the standard definitions, regardless of context.
1485 * GDB now parses C++ symbol and type names more flexibly. For
1488 template<typename T> class C { };
1491 GDB will now correctly handle all of:
1493 ptype C<char const *>
1494 ptype C<char const*>
1495 ptype C<const char *>
1496 ptype C<const char*>
1498 * New features in the GDB remote stub, gdbserver
1500 - The "--wrapper" command-line argument tells gdbserver to use a
1501 wrapper program to launch programs for debugging.
1503 - On PowerPC and S/390 targets, it is now possible to use a single
1504 gdbserver executable to debug both 32-bit and 64-bit programs.
1505 (This requires gdbserver itself to be built as a 64-bit executable.)
1507 - gdbserver uses the new noack protocol mode for TCP connections to
1508 reduce communications latency, if also supported and enabled in GDB.
1510 - Support for the sparc64-linux-gnu target is now included in
1513 - The amd64-linux build of gdbserver now supports debugging both
1514 32-bit and 64-bit programs.
1516 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1517 now support hardware watchpoints, and will use them automatically
1522 GDB now has support for scripting using Python. Whether this is
1523 available is determined at configure time.
1525 New GDB commands can now be written in Python.
1527 * Ada tasking support
1529 Ada tasks can now be inspected in GDB. The following commands have
1533 Print the list of Ada tasks.
1535 Print detailed information about task number N.
1537 Print the task number of the current task.
1539 Switch the context of debugging to task number N.
1541 * Support for user-defined prefixed commands. The "define" command can
1542 add new commands to existing prefixes, e.g. "target".
1544 * Multi-inferior, multi-process debugging.
1546 GDB now has generalized support for multi-inferior debugging. See
1547 "Debugging Multiple Inferiors" in the manual for more information.
1548 Although availability still depends on target support, the command
1549 set is more uniform now. The GNU/Linux specific multi-forks support
1550 has been migrated to this new framework. This implied some user
1551 visible changes; see "New commands" and also "Removed commands"
1554 * Target descriptions can now describe the target OS ABI. See the
1555 "Target Description Format" section in the user manual for more
1558 * Target descriptions can now describe "compatible" architectures
1559 to indicate that the target can execute applications for a different
1560 architecture in addition to those for the main target architecture.
1561 See the "Target Description Format" section in the user manual for
1564 * Multi-architecture debugging.
1566 GDB now includes general supports for debugging applications on
1567 hybrid systems that use more than one single processor architecture
1568 at the same time. Each such hybrid architecture still requires
1569 specific support to be added. The only hybrid architecture supported
1570 in this version of GDB is the Cell Broadband Engine.
1572 * GDB now supports integrated debugging of Cell/B.E. applications that
1573 use both the PPU and SPU architectures. To enable support for hybrid
1574 Cell/B.E. debugging, you need to configure GDB to support both the
1575 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1576 --enable-targets configure option.
1578 * Non-stop mode debugging.
1580 For some targets, GDB now supports an optional mode of operation in
1581 which you can examine stopped threads while other threads continue
1582 to execute freely. This is referred to as non-stop mode, with the
1583 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1584 section in the user manual for more information.
1586 To be able to support remote non-stop debugging, a remote stub needs
1587 to implement the non-stop mode remote protocol extensions, as
1588 described in the "Remote Non-Stop" section of the user manual. The
1589 GDB remote stub, gdbserver, has been adjusted to support these
1590 extensions on linux targets.
1592 * New commands (for set/show, see "New options" below)
1594 catch syscall [NAME(S) | NUMBER(S)]
1595 Catch system calls. Arguments, which should be names of system
1596 calls or their numbers, mean catch only those syscalls. Without
1597 arguments, every syscall will be caught. When the inferior issues
1598 any of the specified syscalls, GDB will stop and announce the system
1599 call, both when it is called and when its call returns. This
1600 feature is currently available with a native GDB running on the
1601 Linux Kernel, under the following architectures: x86, x86_64,
1602 PowerPC and PowerPC64.
1604 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1606 Search memory for a sequence of bytes.
1608 maint set python print-stack
1609 maint show python print-stack
1610 Show a stack trace when an error is encountered in a Python script.
1613 Invoke CODE by passing it to the Python interpreter.
1618 These allow macros to be defined, undefined, and listed
1622 Show operating system information about processes.
1625 List the inferiors currently under GDB's control.
1628 Switch focus to inferior number NUM.
1631 Detach from inferior number NUM.
1634 Kill inferior number NUM.
1638 set spu stop-on-load
1639 show spu stop-on-load
1640 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1642 set spu auto-flush-cache
1643 show spu auto-flush-cache
1644 Control whether to automatically flush the software-managed cache
1645 during Cell/B.E. debugging.
1647 set sh calling-convention
1648 show sh calling-convention
1649 Control the calling convention used when calling SH target functions.
1652 show debug timestamp
1653 Control display of timestamps with GDB debugging output.
1655 set disassemble-next-line
1656 show disassemble-next-line
1657 Control display of disassembled source lines or instructions when
1660 set remote noack-packet
1661 show remote noack-packet
1662 Set/show the use of remote protocol QStartNoAckMode packet. See above
1663 under "New remote packets."
1665 set remote query-attached-packet
1666 show remote query-attached-packet
1667 Control use of remote protocol `qAttached' (query-attached) packet.
1669 set remote read-siginfo-object
1670 show remote read-siginfo-object
1671 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1674 set remote write-siginfo-object
1675 show remote write-siginfo-object
1676 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1679 set remote reverse-continue
1680 show remote reverse-continue
1681 Control use of remote protocol 'bc' (reverse-continue) packet.
1683 set remote reverse-step
1684 show remote reverse-step
1685 Control use of remote protocol 'bs' (reverse-step) packet.
1687 set displaced-stepping
1688 show displaced-stepping
1689 Control displaced stepping mode. Displaced stepping is a way to
1690 single-step over breakpoints without removing them from the debuggee.
1691 Also known as "out-of-line single-stepping".
1694 show debug displaced
1695 Control display of debugging info for displaced stepping.
1697 maint set internal-error
1698 maint show internal-error
1699 Control what GDB does when an internal error is detected.
1701 maint set internal-warning
1702 maint show internal-warning
1703 Control what GDB does when an internal warning is detected.
1708 Use a wrapper program to launch programs for debugging.
1710 set multiple-symbols (all|ask|cancel)
1711 show multiple-symbols
1712 The value of this variable can be changed to adjust the debugger behavior
1713 when an expression or a breakpoint location contains an ambiguous symbol
1714 name (an overloaded function name, for instance).
1716 set breakpoint always-inserted
1717 show breakpoint always-inserted
1718 Keep breakpoints always inserted in the target, as opposed to inserting
1719 them when resuming the target, and removing them when the target stops.
1720 This option can improve debugger performance on slow remote targets.
1722 set arm fallback-mode (arm|thumb|auto)
1723 show arm fallback-mode
1724 set arm force-mode (arm|thumb|auto)
1726 These commands control how ARM GDB determines whether instructions
1727 are ARM or Thumb. The default for both settings is auto, which uses
1728 the current CPSR value for instructions without symbols; previous
1729 versions of GDB behaved as if "set arm fallback-mode arm".
1731 set disable-randomization
1732 show disable-randomization
1733 Standalone programs run with the virtual address space randomization enabled
1734 by default on some platforms. This option keeps the addresses stable across
1735 multiple debugging sessions.
1739 Control whether other threads are stopped or not when some thread hits
1744 Requests that asynchronous execution is enabled in the target, if available.
1745 In this case, it's possible to resume target in the background, and interact
1746 with GDB while the target is running. "show target-async" displays the
1747 current state of asynchronous execution of the target.
1749 set target-wide-charset
1750 show target-wide-charset
1751 The target-wide-charset is the name of the character set that GDB
1752 uses when printing characters whose type is wchar_t.
1754 set tcp auto-retry (on|off)
1756 set tcp connect-timeout
1757 show tcp connect-timeout
1758 These commands allow GDB to retry failed TCP connections to a remote stub
1759 with a specified timeout period; this is useful if the stub is launched
1760 in parallel with GDB but may not be ready to accept connections immediately.
1762 set libthread-db-search-path
1763 show libthread-db-search-path
1764 Control list of directories which GDB will search for appropriate
1767 set schedule-multiple (on|off)
1768 show schedule-multiple
1769 Allow GDB to resume all threads of all processes or only threads of
1770 the current process.
1774 Use more aggressive caching for accesses to the stack. This improves
1775 performance of remote debugging (particularly backtraces) without
1776 affecting correctness.
1778 set interactive-mode (on|off|auto)
1779 show interactive-mode
1780 Control whether GDB runs in interactive mode (on) or not (off).
1781 When in interactive mode, GDB waits for the user to answer all
1782 queries. Otherwise, GDB does not wait and assumes the default
1783 answer. When set to auto (the default), GDB determines which
1784 mode to use based on the stdin settings.
1789 For program forks, this is replaced by the new more generic `info
1790 inferiors' command. To list checkpoints, you can still use the
1791 `info checkpoints' command, which was an alias for the `info forks'
1795 Replaced by the new `inferior' command. To switch between
1796 checkpoints, you can still use the `restart' command, which was an
1797 alias for the `fork' command.
1800 This is removed, since some targets don't have a notion of
1801 processes. To switch between processes, you can still use the
1802 `inferior' command using GDB's own inferior number.
1805 For program forks, this is replaced by the new more generic `kill
1806 inferior' command. To delete a checkpoint, you can still use the
1807 `delete checkpoint' command, which was an alias for the `delete
1811 For program forks, this is replaced by the new more generic `detach
1812 inferior' command. To detach a checkpoint, you can still use the
1813 `detach checkpoint' command, which was an alias for the `detach
1816 * New native configurations
1818 x86/x86_64 Darwin i[34567]86-*-darwin*
1820 x86_64 MinGW x86_64-*-mingw*
1824 Lattice Mico32 lm32-*
1825 x86 DICOS i[34567]86-*-dicos*
1826 x86_64 DICOS x86_64-*-dicos*
1829 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1830 (mingw32ce) debugging.
1836 These commands were actually not implemented on any target.
1838 *** Changes in GDB 6.8
1840 * New native configurations
1842 NetBSD/hppa hppa*-*netbsd*
1843 Xtensa GNU/Linux xtensa*-*-linux*
1847 NetBSD/hppa hppa*-*-netbsd*
1848 Xtensa GNU/Lunux xtensa*-*-linux*
1850 * Change in command line behavior -- corefiles vs. process ids.
1852 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1853 attaching to process NUMBER fails, GDB no longer attempts to open a
1854 core file named NUMBER. Attaching to a program using the -c option
1855 is no longer supported. Instead, use the '-p' or '--pid' options.
1857 * GDB can now be built as a native debugger for debugging Windows x86
1858 (mingw32) Portable Executable (PE) programs.
1860 * Pending breakpoints no longer change their number when their address
1863 * GDB now supports breakpoints with multiple locations,
1864 including breakpoints on C++ constructors, inside C++ templates,
1865 and in inlined functions.
1867 * GDB's ability to debug optimized code has been improved. GDB more
1868 accurately identifies function bodies and lexical blocks that occupy
1869 more than one contiguous range of addresses.
1871 * Target descriptions can now describe registers for PowerPC.
1873 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1874 registers on PowerPC targets.
1876 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1877 targets even when the libthread_db library is not available.
1879 * The GDB remote stub, gdbserver, now supports the new file transfer
1880 commands (remote put, remote get, and remote delete).
1882 * The GDB remote stub, gdbserver, now supports run and attach in
1883 extended-remote mode.
1885 * hppa*64*-*-hpux11* target broken
1886 The debugger is unable to start a program and fails with the following
1887 error: "Error trying to get information about dynamic linker".
1888 The gdb-6.7 release is also affected.
1890 * GDB now supports the --enable-targets= configure option to allow
1891 building a single GDB executable that supports multiple remote
1892 target architectures.
1894 * GDB now supports debugging C and C++ programs which use the
1895 Decimal Floating Point extension. In addition, the PowerPC target
1896 now has a set of pseudo-registers to inspect decimal float values
1897 stored in two consecutive float registers.
1899 * The -break-insert MI command can optionally create pending
1902 * Improved support for debugging Ada
1903 Many improvements to the Ada language support have been made. These
1905 - Better support for Ada2005 interface types
1906 - Improved handling of arrays and slices in general
1907 - Better support for Taft-amendment types
1908 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1910 - Improved command completion in Ada
1913 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1918 set print frame-arguments (all|scalars|none)
1919 show print frame-arguments
1920 The value of this variable can be changed to control which argument
1921 values should be printed by the debugger when displaying a frame.
1926 Transfer files to and from a remote target, and delete remote files.
1933 Transfer files to and from a remote target, and delete remote files.
1935 * New remote packets
1942 Open, close, read, write, and delete files on the remote system.
1945 Attach to an existing process on the remote system, in extended-remote
1949 Run a new process on the remote system, in extended-remote mode.
1951 *** Changes in GDB 6.7
1953 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1954 bfd, libiberty and opcodes, as revealed by static analysis donated by
1955 Coverity, Inc. (http://scan.coverity.com).
1957 * When looking up multiply-defined global symbols, GDB will now prefer the
1958 symbol definition in the current shared library if it was built using the
1959 -Bsymbolic linker option.
1961 * When the Text User Interface (TUI) is not configured, GDB will now
1962 recognize the -tui command-line option and print a message that the TUI
1965 * The GDB remote stub, gdbserver, now has lower overhead for high
1966 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1968 * GDB for MIPS targets now autodetects whether a remote target provides
1969 32-bit or 64-bit register values.
1971 * Support for C++ member pointers has been improved.
1973 * GDB now understands XML target descriptions, which specify the
1974 target's overall architecture. GDB can read a description from
1975 a local file or over the remote serial protocol.
1977 * Vectors of single-byte data use a new integer type which is not
1978 automatically displayed as character or string data.
1980 * The /s format now works with the print command. It displays
1981 arrays of single-byte integers and pointers to single-byte integers
1984 * Target descriptions can now describe target-specific registers,
1985 for architectures which have implemented the support (currently
1986 only ARM, M68K, and MIPS).
1988 * GDB and the GDB remote stub, gdbserver, now support the XScale
1991 * The GDB remote stub, gdbserver, has been updated to support
1992 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1993 has been rewritten to use the standard GDB remote protocol.
1995 * GDB can now step into C++ functions which are called through thunks.
1997 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1999 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
2000 layout. It also supports a TextSeg= and DataSeg= response when only
2001 segment base addresses (rather than offsets) are available.
2003 * The /i format now outputs any trailing branch delay slot instructions
2004 immediately following the last instruction within the count specified.
2006 * The GDB remote protocol "T" stop reply packet now supports a
2007 "library" response. Combined with the new "qXfer:libraries:read"
2008 packet, this response allows GDB to debug shared libraries on targets
2009 where the operating system manages the list of loaded libraries (e.g.
2010 Windows and SymbianOS).
2012 * The GDB remote stub, gdbserver, now supports dynamic link libraries
2013 (DLLs) on Windows and Windows CE targets.
2015 * GDB now supports a faster verification that a .debug file matches its binary
2016 according to its build-id signature, if the signature is present.
2022 Enable or disable hardware flow control (RTS/CTS) on the serial port
2023 when debugging using remote targets.
2025 set mem inaccessible-by-default
2026 show mem inaccessible-by-default
2027 If the target supplies a memory map, for instance via the remote
2028 protocol's "qXfer:memory-map:read" packet, setting this variable
2029 prevents GDB from accessing memory outside the memory map. This
2030 is useful for targets with memory mapped registers or which react
2031 badly to accesses of unmapped address space.
2033 set breakpoint auto-hw
2034 show breakpoint auto-hw
2035 If the target supplies a memory map, for instance via the remote
2036 protocol's "qXfer:memory-map:read" packet, setting this variable
2037 lets GDB use hardware breakpoints automatically for memory regions
2038 where it can not use software breakpoints. This covers both the
2039 "break" command and internal breakpoints used for other commands
2040 including "next" and "finish".
2043 catch exception unhandled
2044 Stop the program execution when Ada exceptions are raised.
2047 Stop the program execution when an Ada assertion failed.
2051 Set an alternate system root for target files. This is a more
2052 general version of "set solib-absolute-prefix", which is now
2053 an alias to "set sysroot".
2056 Provide extended SPU facility status information. This set of
2057 commands is available only when debugging the Cell/B.E. SPU
2060 * New native configurations
2062 OpenBSD/sh sh*-*openbsd*
2065 unset tdesc filename
2067 Use the specified local file as an XML target description, and do
2068 not query the target for its built-in description.
2072 OpenBSD/sh sh*-*-openbsd*
2073 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
2074 Toshiba Media Processor mep-elf
2076 * New remote packets
2079 Ignore the specified signals; pass them directly to the debugged program
2080 without stopping other threads or reporting them to GDB.
2082 qXfer:features:read:
2083 Read an XML target description from the target, which describes its
2088 Read or write contents of an spufs file on the target system. These
2089 packets are available only on the Cell/B.E. SPU architecture.
2091 qXfer:libraries:read:
2092 Report the loaded shared libraries. Combined with new "T" packet
2093 response, this packet allows GDB to debug shared libraries on
2094 targets where the operating system manages the list of loaded
2095 libraries (e.g. Windows and SymbianOS).
2099 Support for these obsolete configurations has been removed.
2107 i[34567]86-*-lynxos*
2108 i[34567]86-*-netware*
2109 i[34567]86-*-sco3.2v5*
2110 i[34567]86-*-sco3.2v4*
2112 i[34567]86-*-sysv4.2*
2115 i[34567]86-*-unixware2*
2116 i[34567]86-*-unixware*
2125 * Other removed features
2132 Various m68k-only ROM monitors.
2139 Various Renesas ROM monitors and debugging interfaces for SH and
2144 Support for a Macraigor serial interface to on-chip debugging.
2145 GDB does not directly support the newer parallel or USB
2150 A debug information format. The predecessor to DWARF 2 and
2151 DWARF 3, which are still supported.
2153 Support for the HP aCC compiler on HP-UX/PA-RISC
2155 SOM-encapsulated symbolic debugging information, automatic
2156 invocation of pxdb, and the aCC custom C++ ABI. This does not
2157 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
2158 with aCC can still be debugged on an assembly level.
2160 MIPS ".pdr" sections
2162 A MIPS-specific format used to describe stack frame layout
2163 in debugging information.
2167 GDB could work with an older version of Guile to debug
2168 the interpreter and Scheme programs running in it.
2170 set mips stack-arg-size
2171 set mips saved-gpreg-size
2173 Use "set mips abi" to control parameter passing for MIPS.
2175 *** Changes in GDB 6.6
2180 Cell Broadband Engine SPU spu-elf
2182 * GDB can now be configured as a cross-debugger targeting native Windows
2183 (mingw32) or Cygwin. It can communicate with a remote debugging stub
2184 running on a Windows system over TCP/IP to debug Windows programs.
2186 * The GDB remote stub, gdbserver, has been updated to support Windows and
2187 Cygwin debugging. Both single-threaded and multi-threaded programs are
2190 * The "set trust-readonly-sections" command works again. This command was
2191 broken in GDB 6.3, 6.4, and 6.5.
2193 * The "load" command now supports writing to flash memory, if the remote
2194 stub provides the required support.
2196 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
2197 longer requires symbolic debug information (e.g. DWARF-2).
2202 unset substitute-path
2203 show substitute-path
2204 Manage a list of substitution rules that GDB uses to rewrite the name
2205 of the directories where the sources are located. This can be useful
2206 for instance when the sources were moved to a different location
2207 between compilation and debugging.
2211 Print each CLI command as it is executed. Each command is prefixed with
2212 a number of `+' symbols representing the nesting depth.
2213 The source command now has a `-v' option to enable the same feature.
2217 The ARM Demon monitor support (RDP protocol, "target rdp").
2219 Kernel Object Display, an embedded debugging feature which only worked with
2220 an obsolete version of Cisco IOS.
2222 The 'set download-write-size' and 'show download-write-size' commands.
2224 * New remote packets
2227 Tell a stub about GDB client features, and request remote target features.
2228 The first feature implemented is PacketSize, which allows the target to
2229 specify the size of packets it can handle - to minimize the number of
2230 packets required and improve performance when connected to a remote
2234 Fetch an OS auxilliary vector from the remote stub. This packet is a
2235 more efficient replacement for qPart:auxv:read.
2237 qXfer:memory-map:read:
2238 Fetch a memory map from the remote stub, including information about
2239 RAM, ROM, and flash memory devices.
2244 Erase and program a flash memory device.
2246 * Removed remote packets
2249 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
2250 used it, and only gdbserver implemented it.
2252 *** Changes in GDB 6.5
2256 Renesas M32C/M16C m32c-elf
2258 Morpho Technologies ms1 ms1-elf
2262 init-if-undefined Initialize a convenience variable, but
2263 only if it doesn't already have a value.
2265 The following commands are presently only implemented for native GNU/Linux:
2267 checkpoint Save a snapshot of the program state.
2269 restart <n> Return the program state to a
2270 previously saved state.
2272 info checkpoints List currently saved checkpoints.
2274 delete-checkpoint <n> Delete a previously saved checkpoint.
2276 set|show detach-on-fork Tell gdb whether to detach from a newly
2277 forked process, or to keep debugging it.
2279 info forks List forks of the user program that
2280 are available to be debugged.
2282 fork <n> Switch to debugging one of several
2283 forks of the user program that are
2284 available to be debugged.
2286 delete-fork <n> Delete a fork from the list of forks
2287 that are available to be debugged (and
2288 kill the forked process).
2290 detach-fork <n> Delete a fork from the list of forks
2291 that are available to be debugged (and
2292 allow the process to continue).
2296 Morpho Technologies ms2 ms1-elf
2298 * Improved Windows host support
2300 GDB now builds as a cross debugger hosted on i686-mingw32, including
2301 native console support, and remote communications using either
2302 network sockets or serial ports.
2304 * Improved Modula-2 language support
2306 GDB can now print most types in the Modula-2 syntax. This includes:
2307 basic types, set types, record types, enumerated types, range types,
2308 pointer types and ARRAY types. Procedure var parameters are correctly
2309 printed and hexadecimal addresses and character constants are also
2310 written in the Modula-2 syntax. Best results can be obtained by using
2311 GNU Modula-2 together with the -gdwarf-2 command line option.
2315 The ARM rdi-share module.
2317 The Netware NLM debug server.
2319 *** Changes in GDB 6.4
2321 * New native configurations
2323 OpenBSD/arm arm*-*-openbsd*
2324 OpenBSD/mips64 mips64-*-openbsd*
2328 Morpho Technologies ms1 ms1-elf
2330 * New command line options
2332 --batch-silent As for --batch, but totally silent.
2333 --return-child-result The debugger will exist with the same value
2334 the child (debugged) program exited with.
2335 --eval-command COMMAND, -ex COMMAND
2336 Execute a single GDB CLI command. This may be
2337 specified multiple times and in conjunction
2338 with the --command (-x) option.
2340 * Deprecated commands removed
2342 The following commands, that were deprecated in 2000, have been
2346 set|show arm disassembly-flavor set|show arm disassembler
2347 othernames set arm disassembler
2348 set|show remotedebug set|show debug remote
2349 set|show archdebug set|show debug arch
2350 set|show eventdebug set|show debug event
2353 * New BSD user-level threads support
2355 It is now possible to debug programs using the user-level threads
2356 library on OpenBSD and FreeBSD. Currently supported (target)
2359 FreeBSD/amd64 x86_64-*-freebsd*
2360 FreeBSD/i386 i386-*-freebsd*
2361 OpenBSD/i386 i386-*-openbsd*
2363 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2364 are not yet supported.
2366 * New support for Matsushita MN10300 w/sim added
2367 (Work in progress). mn10300-elf.
2369 * REMOVED configurations and files
2371 VxWorks and the XDR protocol *-*-vxworks
2372 Motorola MCORE mcore-*-*
2373 National Semiconductor NS32000 ns32k-*-*
2375 * New "set print array-indexes" command
2377 After turning this setting "on", GDB prints the index of each element
2378 when displaying arrays. The default is "off" to preserve the previous
2381 * VAX floating point support
2383 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2385 * User-defined command support
2387 In addition to using $arg0..$arg9 for argument passing, it is now possible
2388 to use $argc to determine now many arguments have been passed. See the
2389 section on user-defined commands in the user manual for more information.
2391 *** Changes in GDB 6.3:
2393 * New command line option
2395 GDB now accepts -l followed by a number to set the timeout for remote
2398 * GDB works with GCC -feliminate-dwarf2-dups
2400 GDB now supports a more compact representation of DWARF-2 debug
2401 information using DW_FORM_ref_addr references. These are produced
2402 by GCC with the option -feliminate-dwarf2-dups and also by some
2403 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2404 to use -feliminate-dwarf2-dups.
2406 * Internationalization
2408 When supported by the host system, GDB will be built with
2409 internationalization (libintl). The task of marking up the sources is
2410 continued, we're looking forward to our first translation.
2414 Initial support for debugging programs compiled with the GNAT
2415 implementation of the Ada programming language has been integrated
2416 into GDB. In this release, support is limited to expression evaluation.
2418 * New native configurations
2420 GNU/Linux/m32r m32r-*-linux-gnu
2424 GDB's remote protocol now includes support for the 'p' packet. This
2425 packet is used to fetch individual registers from a remote inferior.
2427 * END-OF-LIFE registers[] compatibility module
2429 GDB's internal register infrastructure has been completely rewritten.
2430 The new infrastructure making possible the implementation of key new
2431 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2434 GDB 6.3 will be the last release to include the the registers[]
2435 compatibility module that allowed out-of-date configurations to
2436 continue to work. This change directly impacts the following
2446 powerpc bdm protocol
2448 Unless there is activity to revive these configurations, they will be
2449 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2451 * OBSOLETE configurations and files
2453 Configurations that have been declared obsolete in this release have
2454 been commented out. Unless there is activity to revive these
2455 configurations, the next release of GDB will have their sources
2456 permanently REMOVED.
2465 *** Changes in GDB 6.2.1:
2467 * MIPS `break main; run' gave an heuristic-fence-post warning
2469 When attempting to run even a simple program, a warning about
2470 heuristic-fence-post being hit would be reported. This problem has
2473 * MIPS IRIX 'long double' crashed GDB
2475 When examining a long double variable, GDB would get a segmentation
2476 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2477 IRIX long double values).
2481 A bug in the VAX stack code was causing problems with the "next"
2482 command. This problem has been fixed.
2484 *** Changes in GDB 6.2:
2486 * Fix for ``many threads''
2488 On GNU/Linux systems that use the NPTL threads library, a program
2489 rapidly creating and deleting threads would confuse GDB leading to the
2492 ptrace: No such process.
2493 thread_db_get_info: cannot get thread info: generic error
2495 This problem has been fixed.
2497 * "-async" and "-noasync" options removed.
2499 Support for the broken "-noasync" option has been removed (it caused
2502 * New ``start'' command.
2504 This command runs the program until the begining of the main procedure.
2506 * New BSD Kernel Data Access Library (libkvm) interface
2508 Using ``target kvm'' it is now possible to debug kernel core dumps and
2509 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2510 platforms. Currently supported (native-only) configurations are:
2512 FreeBSD/amd64 x86_64-*-freebsd*
2513 FreeBSD/i386 i?86-*-freebsd*
2514 NetBSD/i386 i?86-*-netbsd*
2515 NetBSD/m68k m68*-*-netbsd*
2516 NetBSD/sparc sparc-*-netbsd*
2517 OpenBSD/amd64 x86_64-*-openbsd*
2518 OpenBSD/i386 i?86-*-openbsd*
2519 OpenBSD/m68k m68*-openbsd*
2520 OpenBSD/sparc sparc-*-openbsd*
2522 * Signal trampoline code overhauled
2524 Many generic problems with GDB's signal handling code have been fixed.
2525 These include: backtraces through non-contiguous stacks; recognition
2526 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2527 call; backtrace through a signal trampoline; step into and out of
2528 signal handlers; and single-stepping in the signal trampoline.
2530 Please note that kernel bugs are a limiting factor here. These
2531 features have been shown to work on an s390 GNU/Linux system that
2532 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2534 * Cygwin support for DWARF 2 added.
2536 * New native configurations
2538 GNU/Linux/hppa hppa*-*-linux*
2539 OpenBSD/hppa hppa*-*-openbsd*
2540 OpenBSD/m68k m68*-*-openbsd*
2541 OpenBSD/m88k m88*-*-openbsd*
2542 OpenBSD/powerpc powerpc-*-openbsd*
2543 NetBSD/vax vax-*-netbsd*
2544 OpenBSD/vax vax-*-openbsd*
2546 * END-OF-LIFE frame compatibility module
2548 GDB's internal frame infrastructure has been completely rewritten.
2549 The new infrastructure making it possible to support key new features
2550 including DWARF 2 Call Frame Information. To aid in the task of
2551 migrating old configurations to this new infrastructure, a
2552 compatibility module, that allowed old configurations to continue to
2553 work, was also included.
2555 GDB 6.2 will be the last release to include this frame compatibility
2556 module. This change directly impacts the following configurations:
2566 Unless there is activity to revive these configurations, they will be
2567 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2569 * REMOVED configurations and files
2571 Sun 3, running SunOS 3 m68*-*-sunos3*
2572 Sun 3, running SunOS 4 m68*-*-sunos4*
2573 Sun 2, running SunOS 3 m68000-*-sunos3*
2574 Sun 2, running SunOS 4 m68000-*-sunos4*
2575 Motorola 680x0 running LynxOS m68*-*-lynxos*
2576 AT&T 3b1/Unix pc m68*-att-*
2577 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2578 decstation mips-dec-* mips-little-*
2579 riscos mips-*-riscos* mips-*-sysv*
2580 sonymips mips-sony-*
2581 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2583 *** Changes in GDB 6.1.1:
2585 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2587 The TUI (Text-mode User Interface) is now built as part of a default
2588 GDB configuration. It is enabled by either selecting the TUI with the
2589 command line option "-i=tui" or by running the separate "gdbtui"
2590 program. For more information on the TUI, see the manual "Debugging
2593 * Pending breakpoint support (also included in GDB 6.1)
2595 Support has been added to allow you to specify breakpoints in shared
2596 libraries that have not yet been loaded. If a breakpoint location
2597 cannot be found, and the "breakpoint pending" option is set to auto,
2598 GDB queries you if you wish to make the breakpoint pending on a future
2599 shared-library load. If and when GDB resolves the breakpoint symbol,
2600 the pending breakpoint is removed as one or more regular breakpoints
2603 Pending breakpoints are very useful for GCJ Java debugging.
2605 * Fixed ISO-C build problems
2607 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2608 non ISO-C code that stopped them being built using a more strict ISO-C
2609 compiler (e.g., IBM's C compiler).
2611 * Fixed build problem on IRIX 5
2613 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2614 wasn't able to compile compile on an IRIX 5 system.
2616 * Added execute permission to gdb/gdbserver/configure
2618 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2619 permission. This bug would cause configure to fail on a number of
2620 systems (Solaris, IRIX). Ref: server/519.
2622 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2624 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2625 has been updated to use constant array sizes.
2627 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2629 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2630 its generated DWARF Call Frame Info. This encoding was causing GDB to
2631 panic, that panic has been fixed. Ref: gdb/1628.
2633 * Fixed a problem when examining parameters in shared library code.
2635 When examining parameters in optimized shared library code generated
2636 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2637 not available''. GDB now correctly displays the variable's value.
2639 *** Changes in GDB 6.1:
2641 * Removed --with-mmalloc
2643 Support for the mmalloc memory manager has been removed, as it
2644 conflicted with the internal gdb byte cache.
2646 * Changes in AMD64 configurations
2648 The AMD64 target now includes the %cs and %ss registers. As a result
2649 the AMD64 remote protocol has changed; this affects the floating-point
2650 and SSE registers. If you rely on those registers for your debugging,
2651 you should upgrade gdbserver on the remote side.
2653 * Revised SPARC target
2655 The SPARC target has been completely revised, incorporating the
2656 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2657 support for LynxOS and SunOS 4 has been dropped. Calling functions
2658 from within GDB on operating systems with a non-executable stack
2659 (Solaris, OpenBSD) now works.
2663 GDB has a new C++ demangler which does a better job on the mangled
2664 names generated by current versions of g++. It also runs faster, so
2665 with this and other changes gdb should now start faster on large C++
2668 * DWARF 2 Location Expressions
2670 GDB support for location expressions has been extended to support function
2671 arguments and frame bases. Older versions of GDB could crash when they
2674 * C++ nested types and namespaces
2676 GDB's support for nested types and namespaces in C++ has been
2677 improved, especially if you use the DWARF 2 debugging format. (This
2678 is the default for recent versions of GCC on most platforms.)
2679 Specifically, if you have a class "Inner" defined within a class or
2680 namespace "Outer", then GDB realizes that the class's name is
2681 "Outer::Inner", not simply "Inner". This should greatly reduce the
2682 frequency of complaints about not finding RTTI symbols. In addition,
2683 if you are stopped at inside of a function defined within a namespace,
2684 GDB modifies its name lookup accordingly.
2686 * New native configurations
2688 NetBSD/amd64 x86_64-*-netbsd*
2689 OpenBSD/amd64 x86_64-*-openbsd*
2690 OpenBSD/alpha alpha*-*-openbsd*
2691 OpenBSD/sparc sparc-*-openbsd*
2692 OpenBSD/sparc64 sparc64-*-openbsd*
2694 * New debugging protocols
2696 M32R with SDI protocol m32r-*-elf*
2698 * "set prompt-escape-char" command deleted.
2700 The command "set prompt-escape-char" has been deleted. This command,
2701 and its very obscure effet on GDB's prompt, was never documented,
2702 tested, nor mentioned in the NEWS file.
2704 * OBSOLETE configurations and files
2706 Configurations that have been declared obsolete in this release have
2707 been commented out. Unless there is activity to revive these
2708 configurations, the next release of GDB will have their sources
2709 permanently REMOVED.
2711 Sun 3, running SunOS 3 m68*-*-sunos3*
2712 Sun 3, running SunOS 4 m68*-*-sunos4*
2713 Sun 2, running SunOS 3 m68000-*-sunos3*
2714 Sun 2, running SunOS 4 m68000-*-sunos4*
2715 Motorola 680x0 running LynxOS m68*-*-lynxos*
2716 AT&T 3b1/Unix pc m68*-att-*
2717 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2718 decstation mips-dec-* mips-little-*
2719 riscos mips-*-riscos* mips-*-sysv*
2720 sonymips mips-sony-*
2721 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2723 * REMOVED configurations and files
2725 SGI Irix-4.x mips-sgi-irix4 or iris4
2726 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2727 Z8000 simulator z8k-zilog-none or z8ksim
2728 Matsushita MN10200 w/simulator mn10200-*-*
2729 H8/500 simulator h8500-hitachi-hms or h8500hms
2730 HP/PA running BSD hppa*-*-bsd*
2731 HP/PA running OSF/1 hppa*-*-osf*
2732 HP/PA Pro target hppa*-*-pro*
2733 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2734 386BSD i[3456]86-*-bsd*
2735 Sequent family i[3456]86-sequent-sysv4*
2736 i[3456]86-sequent-sysv*
2737 i[3456]86-sequent-bsd*
2738 SPARC running LynxOS sparc-*-lynxos*
2739 SPARC running SunOS 4 sparc-*-sunos4*
2740 Tsqware Sparclet sparclet-*-*
2741 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2743 *** Changes in GDB 6.0:
2747 Support for debugging the Objective-C programming language has been
2748 integrated into GDB.
2750 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2752 DWARF 2's Call Frame Information makes available compiler generated
2753 information that more exactly describes the program's run-time stack.
2754 By using this information, GDB is able to provide more robust stack
2757 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2758 have been updated to use a new backtrace mechanism which includes
2759 DWARF 2 CFI support.
2763 GDB's remote protocol has been extended to include support for hosted
2764 file I/O (where the remote target uses GDB's file system). See GDB's
2765 remote protocol documentation for details.
2767 * All targets using the new architecture framework.
2769 All of GDB's targets have been updated to use the new internal
2770 architecture framework. The way is now open for future GDB releases
2771 to include cross-architecture native debugging support (i386 on amd64,
2774 * GNU/Linux's Thread Local Storage (TLS)
2776 GDB now includes support for for the GNU/Linux implementation of
2777 per-thread variables.
2779 * GNU/Linux's Native POSIX Thread Library (NPTL)
2781 GDB's thread code has been updated to work with either the new
2782 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2784 * Separate debug info.
2786 GDB, in conjunction with BINUTILS, now supports a mechanism for
2787 automatically loading debug information from a separate file. Instead
2788 of shipping full debug and non-debug versions of system libraries,
2789 system integrators can now instead ship just the stripped libraries
2790 and optional debug files.
2792 * DWARF 2 Location Expressions
2794 DWARF 2 Location Expressions allow the compiler to more completely
2795 describe the location of variables (even in optimized code) to the
2798 GDB now includes preliminary support for location expressions (support
2799 for DW_OP_piece is still missing).
2803 A number of long standing bugs that caused GDB to die while starting a
2804 Java application have been fixed. GDB's Java support is now
2805 considered "useable".
2807 * GNU/Linux support for fork, vfork, and exec.
2809 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2810 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2813 * GDB supports logging output to a file
2815 There are two new commands, "set logging" and "show logging", which can be
2816 used to capture GDB's output to a file.
2818 * The meaning of "detach" has changed for gdbserver
2820 The "detach" command will now resume the application, as documented. To
2821 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2824 * d10v, m68hc11 `regs' command deprecated
2826 The `info registers' command has been updated so that it displays the
2827 registers using a format identical to the old `regs' command.
2831 A new command, "maint set profile on/off", has been added. This command can
2832 be used to enable or disable profiling while running GDB, to profile a
2833 session or a set of commands. In addition there is a new configure switch,
2834 "--enable-profiling", which will cause GDB to be compiled with profiling
2835 data, for more informative profiling results.
2837 * Default MI syntax changed to "mi2".
2839 The default MI (machine interface) syntax, enabled by the command line
2840 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2841 "mi1", can be enabled by specifying the option "-i=mi1".
2843 Support for the original "mi0" syntax (included in GDB 5.0) has been
2846 Fix for gdb/192: removed extraneous space when displaying frame level.
2847 Fix for gdb/672: update changelist is now output in mi list format.
2848 Fix for gdb/702: a -var-assign that updates the value now shows up
2849 in a subsequent -var-update.
2851 * New native configurations.
2853 FreeBSD/amd64 x86_64-*-freebsd*
2855 * Multi-arched targets.
2857 HP/PA HPUX11 hppa*-*-hpux*
2858 Renesas M32R/D w/simulator m32r-*-elf*
2860 * OBSOLETE configurations and files
2862 Configurations that have been declared obsolete in this release have
2863 been commented out. Unless there is activity to revive these
2864 configurations, the next release of GDB will have their sources
2865 permanently REMOVED.
2867 Z8000 simulator z8k-zilog-none or z8ksim
2868 Matsushita MN10200 w/simulator mn10200-*-*
2869 H8/500 simulator h8500-hitachi-hms or h8500hms
2870 HP/PA running BSD hppa*-*-bsd*
2871 HP/PA running OSF/1 hppa*-*-osf*
2872 HP/PA Pro target hppa*-*-pro*
2873 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2874 Sequent family i[3456]86-sequent-sysv4*
2875 i[3456]86-sequent-sysv*
2876 i[3456]86-sequent-bsd*
2877 Tsqware Sparclet sparclet-*-*
2878 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2880 * REMOVED configurations and files
2883 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2884 IBM AIX PS/2 i[3456]86-*-aix
2885 i386 running Mach 3.0 i[3456]86-*-mach3*
2886 i386 running Mach i[3456]86-*-mach*
2887 i386 running OSF/1 i[3456]86-*osf1mk*
2888 HP/Apollo 68k Family m68*-apollo*-sysv*,
2890 m68*-hp-bsd*, m68*-hp-hpux*
2891 Argonaut Risc Chip (ARC) arc-*-*
2892 Mitsubishi D30V d30v-*-*
2893 Fujitsu FR30 fr30-*-elf*
2894 OS/9000 i[34]86-*-os9k
2895 I960 with MON960 i960-*-coff
2897 * MIPS $fp behavior changed
2899 The convenience variable $fp, for the MIPS, now consistently returns
2900 the address of the current frame's base. Previously, depending on the
2901 context, $fp could refer to either $sp or the current frame's base
2902 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2903 The GNU Source-Level Debugger''.
2905 *** Changes in GDB 5.3:
2907 * GNU/Linux shared library multi-threaded performance improved.
2909 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2910 `/proc', in preference to `ptrace' for memory reads. This may result
2911 in an improvement in the start-up time of multi-threaded, shared
2912 library applications when run under GDB. One GDB user writes: ``loads
2913 shared libs like mad''.
2915 * ``gdbserver'' now supports multi-threaded applications on some targets
2917 Support for debugging multi-threaded applications which use
2918 the GNU/Linux LinuxThreads package has been added for
2919 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2920 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2922 * GDB now supports C/C++ preprocessor macros.
2924 GDB now expands preprocessor macro invocations in C/C++ expressions,
2925 and provides various commands for showing macro definitions and how
2928 The new command `macro expand EXPRESSION' expands any macro
2929 invocations in expression, and shows the result.
2931 The new command `show macro MACRO-NAME' shows the definition of the
2932 macro named MACRO-NAME, and where it was defined.
2934 Most compilers don't include information about macros in the debugging
2935 information by default. In GCC 3.1, for example, you need to compile
2936 your program with the options `-gdwarf-2 -g3'. If the macro
2937 information is present in the executable, GDB will read it.
2939 * Multi-arched targets.
2941 DEC Alpha (partial) alpha*-*-*
2942 DEC VAX (partial) vax-*-*
2944 National Semiconductor NS32000 (partial) ns32k-*-*
2945 Motorola 68000 (partial) m68k-*-*
2946 Motorola MCORE mcore-*-*
2950 Fujitsu FRV architecture added by Red Hat frv*-*-*
2953 * New native configurations
2955 Alpha NetBSD alpha*-*-netbsd*
2956 SH NetBSD sh*-*-netbsdelf*
2957 MIPS NetBSD mips*-*-netbsd*
2958 UltraSPARC NetBSD sparc64-*-netbsd*
2960 * OBSOLETE configurations and files
2962 Configurations that have been declared obsolete in this release have
2963 been commented out. Unless there is activity to revive these
2964 configurations, the next release of GDB will have their sources
2965 permanently REMOVED.
2967 Mitsubishi D30V d30v-*-*
2968 OS/9000 i[34]86-*-os9k
2969 IBM AIX PS/2 i[3456]86-*-aix
2970 Fujitsu FR30 fr30-*-elf*
2971 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2972 Argonaut Risc Chip (ARC) arc-*-*
2973 i386 running Mach 3.0 i[3456]86-*-mach3*
2974 i386 running Mach i[3456]86-*-mach*
2975 i386 running OSF/1 i[3456]86-*osf1mk*
2976 HP/Apollo 68k Family m68*-apollo*-sysv*,
2978 m68*-hp-bsd*, m68*-hp-hpux*
2979 I960 with MON960 i960-*-coff
2981 * OBSOLETE languages
2983 CHILL, a Pascal like language used by telecommunications companies.
2985 * REMOVED configurations and files
2987 AMD 29k family via UDI a29k-amd-udi, udi29k
2988 A29K VxWorks a29k-*-vxworks
2989 AMD 29000 embedded, using EBMON a29k-none-none
2990 AMD 29000 embedded with COFF a29k-none-coff
2991 AMD 29000 embedded with a.out a29k-none-aout
2993 testsuite/gdb.hp/gdb.threads-hp/ directory
2995 * New command "set max-user-call-depth <nnn>"
2997 This command allows the user to limit the call depth of user-defined
2998 commands. The default is 1024.
3000 * Changes in FreeBSD/i386 native debugging.
3002 Support for the "generate-core-file" has been added.
3004 * New commands "dump", "append", and "restore".
3006 These commands allow data to be copied from target memory
3007 to a bfd-format or binary file (dump and append), and back
3008 from a file into memory (restore).
3010 * Improved "next/step" support on multi-processor Alpha Tru64.
3012 The previous single-step mechanism could cause unpredictable problems,
3013 including the random appearance of SIGSEGV or SIGTRAP signals. The use
3014 of a software single-step mechanism prevents this.
3016 *** Changes in GDB 5.2.1:
3024 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
3025 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
3026 Fix, by Joel Brobecker imported from mainline.
3028 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
3029 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
3030 Fix, by Fred Fish, imported from mainline.
3032 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
3033 Surprisingly enough, it works now.
3034 By Michal Ludvig, imported from mainline.
3036 i386 hardware watchpoint support:
3037 avoid misses on second run for some targets.
3038 By Pierre Muller, imported from mainline.
3040 *** Changes in GDB 5.2:
3042 * New command "set trust-readonly-sections on[off]".
3044 This command is a hint that tells gdb that read-only sections
3045 really are read-only (ie. that their contents will not change).
3046 In this mode, gdb will go to the object file rather than the
3047 target to read memory from read-only sections (such as ".text").
3048 This can be a significant performance improvement on some
3049 (notably embedded) targets.
3051 * New command "generate-core-file" (or "gcore").
3053 This new gdb command allows the user to drop a core file of the child
3054 process state at any time. So far it's been implemented only for
3055 GNU/Linux and Solaris, but should be relatively easily ported to other
3056 hosts. Argument is core file name (defaults to core.<pid>).
3058 * New command line option
3060 GDB now accepts --pid or -p followed by a process id.
3062 * Change in command line behavior -- corefiles vs. process ids.
3064 There is a subtle behavior in the way in which GDB handles
3065 command line arguments. The first non-flag argument is always
3066 a program to debug, but the second non-flag argument may either
3067 be a corefile or a process id. Previously, GDB would attempt to
3068 open the second argument as a corefile, and if that failed, would
3069 issue a superfluous error message and then attempt to attach it as
3070 a process. Now, if the second argument begins with a non-digit,
3071 it will be treated as a corefile. If it begins with a digit,
3072 GDB will attempt to attach it as a process, and if no such process
3073 is found, will then attempt to open it as a corefile.
3075 * Changes in ARM configurations.
3077 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
3078 configuration is fully multi-arch.
3080 * New native configurations
3082 ARM NetBSD arm*-*-netbsd*
3083 x86 OpenBSD i[3456]86-*-openbsd*
3084 AMD x86-64 running GNU/Linux x86_64-*-linux-*
3085 Sparc64 running FreeBSD sparc64-*-freebsd*
3089 Sanyo XStormy16 xstormy16-elf
3091 * OBSOLETE configurations and files
3093 Configurations that have been declared obsolete in this release have
3094 been commented out. Unless there is activity to revive these
3095 configurations, the next release of GDB will have their sources
3096 permanently REMOVED.
3098 AMD 29k family via UDI a29k-amd-udi, udi29k
3099 A29K VxWorks a29k-*-vxworks
3100 AMD 29000 embedded, using EBMON a29k-none-none
3101 AMD 29000 embedded with COFF a29k-none-coff
3102 AMD 29000 embedded with a.out a29k-none-aout
3104 testsuite/gdb.hp/gdb.threads-hp/ directory
3106 * REMOVED configurations and files
3108 TI TMS320C80 tic80-*-*
3110 PowerPC Solaris powerpcle-*-solaris*
3111 PowerPC Windows NT powerpcle-*-cygwin32
3112 PowerPC Netware powerpc-*-netware*
3113 Harris/CXUX m88k m88*-harris-cxux*
3114 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3115 ns32k-utek-sysv* ns32k-utek-*
3116 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3117 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3118 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3119 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3120 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
3122 * Changes to command line processing
3124 The new `--args' feature can be used to specify command-line arguments
3125 for the inferior from gdb's command line.
3127 * Changes to key bindings
3129 There is a new `operate-and-get-next' function bound to `C-o'.
3131 *** Changes in GDB 5.1.1
3133 Fix compile problem on DJGPP.
3135 Fix a problem with floating-point registers on the i386 being
3138 Fix to stop GDB crashing on .debug_str debug info.
3140 Numerous documentation fixes.
3142 Numerous testsuite fixes.
3144 *** Changes in GDB 5.1:
3146 * New native configurations
3148 Alpha FreeBSD alpha*-*-freebsd*
3149 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
3150 MIPS GNU/Linux mips*-*-linux*
3151 MIPS SGI Irix 6.x mips*-sgi-irix6*
3152 ia64 AIX ia64-*-aix*
3153 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
3157 Motorola 68HC11 and 68HC12 m68hc11-elf
3159 UltraSparc running GNU/Linux sparc64-*-linux*
3161 * OBSOLETE configurations and files
3163 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
3164 Harris/CXUX m88k m88*-harris-cxux*
3165 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
3166 ns32k-utek-sysv* ns32k-utek-*
3167 TI TMS320C80 tic80-*-*
3169 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
3170 PowerPC Solaris powerpcle-*-solaris*
3171 PowerPC Windows NT powerpcle-*-cygwin32
3172 PowerPC Netware powerpc-*-netware*
3173 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
3174 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
3175 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
3176 Apple Macintosh (MPW) host N/A
3178 stuff.c (Program to stuff files into a specially prepared space in kdb)
3179 kdb-start.c (Main loop for the standalone kernel debugger)
3181 Configurations that have been declared obsolete in this release have
3182 been commented out. Unless there is activity to revive these
3183 configurations, the next release of GDB will have their sources
3184 permanently REMOVED.
3186 * REMOVED configurations and files
3188 Altos 3068 m68*-altos-*
3189 Convex c1-*-*, c2-*-*
3191 ARM RISCix arm-*-* (as host)
3195 * GDB has been converted to ISO C.
3197 GDB's source code has been converted to ISO C. In particular, the
3198 sources are fully protoized, and rely on standard headers being
3203 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
3205 * The MI enabled by default.
3207 The new machine oriented interface (MI) introduced in GDB 5.0 has been
3208 revised and enabled by default. Packages which use GDB as a debugging
3209 engine behind a UI or another front end are encouraged to switch to
3210 using the GDB/MI interface, instead of the old annotations interface
3211 which is now deprecated.
3213 * Support for debugging Pascal programs.
3215 GDB now includes support for debugging Pascal programs. The following
3216 main features are supported:
3218 - Pascal-specific data types such as sets;
3220 - automatic recognition of Pascal sources based on file-name
3223 - Pascal-style display of data types, variables, and functions;
3225 - a Pascal expression parser.
3227 However, some important features are not yet supported.
3229 - Pascal string operations are not supported at all;
3231 - there are some problems with boolean types;
3233 - Pascal type hexadecimal constants are not supported
3234 because they conflict with the internal variables format;
3236 - support for Pascal objects and classes is not full yet;
3238 - unlike Pascal, GDB is case-sensitive for symbol names.
3240 * Changes in completion.
3242 Commands such as `shell', `run' and `set args', which pass arguments
3243 to inferior programs, now complete on file names, similar to what
3244 users expect at the shell prompt.
3246 Commands which accept locations, such as `disassemble', `print',
3247 `breakpoint', `until', etc. now complete on filenames as well as
3248 program symbols. Thus, if you type "break foob TAB", and the source
3249 files linked into the programs include `foobar.c', that file name will
3250 be one of the candidates for completion. However, file names are not
3251 considered for completion after you typed a colon that delimits a file
3252 name from a name of a function in that file, as in "break foo.c:bar".
3254 `set demangle-style' completes on available demangling styles.
3256 * New platform-independent commands:
3258 It is now possible to define a post-hook for a command as well as a
3259 hook that runs before the command. For more details, see the
3260 documentation of `hookpost' in the GDB manual.
3262 * Changes in GNU/Linux native debugging.
3264 Support for debugging multi-threaded programs has been completely
3265 revised for all platforms except m68k and sparc. You can now debug as
3266 many threads as your system allows you to have.
3268 Attach/detach is supported for multi-threaded programs.
3270 Support for SSE registers was added for x86. This doesn't work for
3271 multi-threaded programs though.
3273 * Changes in MIPS configurations.
3275 Multi-arch support is enabled for all MIPS configurations.
3277 GDB can now be built as native debugger on SGI Irix 6.x systems for
3278 debugging n32 executables. (Debugging 64-bit executables is not yet
3281 * Unified support for hardware watchpoints in all x86 configurations.
3283 Most (if not all) native x86 configurations support hardware-assisted
3284 breakpoints and watchpoints in a unified manner. This support
3285 implements debug register sharing between watchpoints, which allows to
3286 put a virtually infinite number of watchpoints on the same address,
3287 and also supports watching regions up to 16 bytes with several debug
3290 The new maintenance command `maintenance show-debug-regs' toggles
3291 debugging print-outs in functions that insert, remove, and test
3292 watchpoints and hardware breakpoints.
3294 * Changes in the DJGPP native configuration.
3296 New command ``info dos sysinfo'' displays assorted information about
3297 the CPU, OS, memory, and DPMI server.
3299 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
3300 display information about segment descriptors stored in GDT, LDT, and
3303 New commands ``info dos pde'' and ``info dos pte'' display entries
3304 from Page Directory and Page Tables (for now works with CWSDPMI only).
3305 New command ``info dos address-pte'' displays the Page Table entry for
3306 a given linear address.
3308 GDB can now pass command lines longer than 126 characters to the
3309 program being debugged (requires an update to the libdbg.a library
3310 which is part of the DJGPP development kit).
3312 DWARF2 debug info is now supported.
3314 It is now possible to `step' and `next' through calls to `longjmp'.
3316 * Changes in documentation.
3318 All GDB documentation was converted to GFDL, the GNU Free
3319 Documentation License.
3321 Tracepoints-related commands are now fully documented in the GDB
3324 TUI, the Text-mode User Interface, is now documented in the manual.
3326 Tracepoints-related commands are now fully documented in the GDB
3329 The "GDB Internals" manual now has an index. It also includes
3330 documentation of `ui_out' functions, GDB coding standards, x86
3331 hardware watchpoints, and memory region attributes.
3333 * GDB's version number moved to ``version.in''
3335 The Makefile variable VERSION has been replaced by the file
3336 ``version.in''. People creating GDB distributions should update the
3337 contents of this file.
3341 GUD support is now a standard part of the EMACS distribution.
3343 *** Changes in GDB 5.0:
3345 * Improved support for debugging FP programs on x86 targets
3347 Unified and much-improved support for debugging floating-point
3348 programs on all x86 targets. In particular, ``info float'' now
3349 displays the FP registers in the same format on all x86 targets, with
3350 greater level of detail.
3352 * Improvements and bugfixes in hardware-assisted watchpoints
3354 It is now possible to watch array elements, struct members, and
3355 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3356 on x86 targets no longer erroneously trigger when the address is
3359 * Improvements in the native DJGPP version of GDB
3361 The distribution now includes all the scripts and auxiliary files
3362 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3363 machines ``out of the box''.
3365 The DJGPP version can now debug programs that use signals. It is
3366 possible to catch signals that happened in the debuggee, deliver
3367 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3368 would kill the program being debugged.) Programs that hook hardware
3369 interrupts (keyboard, timer, etc.) can also be debugged.
3371 It is now possible to debug DJGPP programs that redirect their
3372 standard handles or switch them to raw (as opposed to cooked) mode, or
3373 even close them. The command ``run < foo > bar'' works as expected,
3374 and ``info terminal'' reports useful information about the debuggee's
3375 terminal, including raw/cooked mode, redirection, etc.
3377 The DJGPP version now uses termios functions for console I/O, which
3378 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3381 DOS-style file names with drive letters are now fully supported by
3384 It is now possible to debug DJGPP programs that switch their working
3385 directory. It is also possible to rerun the debuggee any number of
3386 times without restarting GDB; thus, you can use the same setup,
3387 breakpoints, etc. for many debugging sessions.
3389 * New native configurations
3391 ARM GNU/Linux arm*-*-linux*
3392 PowerPC GNU/Linux powerpc-*-linux*
3396 Motorola MCore mcore-*-*
3397 x86 VxWorks i[3456]86-*-vxworks*
3398 PowerPC VxWorks powerpc-*-vxworks*
3399 TI TMS320C80 tic80-*-*
3401 * OBSOLETE configurations
3403 Altos 3068 m68*-altos-*
3404 Convex c1-*-*, c2-*-*
3406 ARM RISCix arm-*-* (as host)
3409 Configurations that have been declared obsolete will be commented out,
3410 but the code will be left in place. If there is no activity to revive
3411 these configurations before the next release of GDB, the sources will
3412 be permanently REMOVED.
3414 * Gould support removed
3416 Support for the Gould PowerNode and NP1 has been removed.
3418 * New features for SVR4
3420 On SVR4 native platforms (such as Solaris), if you attach to a process
3421 without first loading a symbol file, GDB will now attempt to locate and
3422 load symbols from the running process's executable file.
3424 * Many C++ enhancements
3426 C++ support has been greatly improved. Overload resolution now works properly
3427 in almost all cases. RTTI support is on the way.
3429 * Remote targets can connect to a sub-program
3431 A popen(3) style serial-device has been added. This device starts a
3432 sub-process (such as a stand-alone simulator) and then communicates
3433 with that. The sub-program to run is specified using the syntax
3434 ``|<program> <args>'' vis:
3436 (gdb) set remotedebug 1
3437 (gdb) target extended-remote |mn10300-elf-sim program-args
3439 * MIPS 64 remote protocol
3441 A long standing bug in the mips64 remote protocol where by GDB
3442 expected certain 32 bit registers (ex SR) to be transfered as 32
3443 instead of 64 bits has been fixed.
3445 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3446 added to provide backward compatibility with older versions of GDB.
3448 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3450 The command ``set remotebinarydownload'' command has been replaced by
3451 ``set remote X-packet''. Other commands in ``set remote'' family
3452 include ``set remote P-packet''.
3454 * Breakpoint commands accept ranges.
3456 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3457 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3458 ``tracepoint passcount'' also accepts a range of tracepoints.
3460 * ``apropos'' command added.
3462 The ``apropos'' command searches through command names and
3463 documentation strings, printing out matches, making it much easier to
3464 try to find a command that does what you are looking for.
3468 A new machine oriented interface (MI) has been added to GDB. This
3469 interface is designed for debug environments running GDB as a separate
3470 process. This is part of the long term libGDB project. See the
3471 "GDB/MI" chapter of the GDB manual for further information. It can be
3472 enabled by configuring with:
3474 .../configure --enable-gdbmi
3476 *** Changes in GDB-4.18:
3478 * New native configurations
3480 HP-UX 10.20 hppa*-*-hpux10.20
3481 HP-UX 11.x hppa*-*-hpux11.0*
3482 M68K GNU/Linux m68*-*-linux*
3486 Fujitsu FR30 fr30-*-elf*
3487 Intel StrongARM strongarm-*-*
3488 Mitsubishi D30V d30v-*-*
3490 * OBSOLETE configurations
3492 Gould PowerNode, NP1 np1-*-*, pn-*-*
3494 Configurations that have been declared obsolete will be commented out,
3495 but the code will be left in place. If there is no activity to revive
3496 these configurations before the next release of GDB, the sources will
3497 be permanently REMOVED.
3501 As a compatibility experiment, GDB's source files buildsym.h and
3502 buildsym.c have been converted to pure standard C, no longer
3503 containing any K&R compatibility code. We believe that all systems in
3504 use today either come with a standard C compiler, or have a GCC port
3505 available. If this is not true, please report the affected
3506 configuration to bug-gdb@gnu.org immediately. See the README file for
3507 information about getting a standard C compiler if you don't have one
3512 GDB now uses readline 2.2.
3514 * set extension-language
3516 You can now control the mapping between filename extensions and source
3517 languages by using the `set extension-language' command. For instance,
3518 you can ask GDB to treat .c files as C++ by saying
3519 set extension-language .c c++
3520 The command `info extensions' lists all of the recognized extensions
3521 and their associated languages.
3523 * Setting processor type for PowerPC and RS/6000
3525 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3526 you can use the `set processor' command to specify what variant of the
3527 PowerPC family you are debugging. The command
3531 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3532 following PowerPC and RS6000 variants:
3534 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3535 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3537 403GC IBM PowerPC 403GC
3538 505 Motorola PowerPC 505
3539 860 Motorola PowerPC 860 or 850
3540 601 Motorola PowerPC 601
3541 602 Motorola PowerPC 602
3542 603 Motorola/IBM PowerPC 603 or 603e
3543 604 Motorola PowerPC 604 or 604e
3544 750 Motorola/IBM PowerPC 750 or 750
3546 At the moment, this command just tells GDB what to name the
3547 special-purpose processor registers. Since almost all the affected
3548 registers are inaccessible to user-level programs, this command is
3549 only useful for remote debugging in its present form.
3553 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3554 more extensive support for HP-UX. Added features include shared
3555 library support, kernel threads and hardware watchpoints for 11.00,
3556 support for HP's ANSI C and C++ compilers, and a compatibility mode
3557 for xdb and dbx commands.
3561 HP's donation includes the new concept of catchpoints, which is a
3562 generalization of the old catch command. On HP-UX, it is now possible
3563 to catch exec, fork, and vfork, as well as library loading.
3565 This means that the existing catch command has changed; its first
3566 argument now specifies the type of catch to be set up. See the
3567 output of "help catch" for a list of catchpoint types.
3569 * Debugging across forks
3571 On HP-UX, you can choose which process to debug when a fork() happens
3576 HP has donated a curses-based terminal user interface (TUI). To get
3577 it, build with --enable-tui. Although this can be enabled for any
3578 configuration, at present it only works for native HP debugging.
3580 * GDB remote protocol additions
3582 A new protocol packet 'X' that writes binary data is now available.
3583 Default behavior is to try 'X', then drop back to 'M' if the stub
3584 fails to respond. The settable variable `remotebinarydownload'
3585 allows explicit control over the use of 'X'.
3587 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3588 full 64-bit address. The command
3590 set remoteaddresssize 32
3592 can be used to revert to the old behaviour. For existing remote stubs
3593 the change should not be noticed, as the additional address information
3596 In order to assist in debugging stubs, you may use the maintenance
3597 command `packet' to send any text string to the stub. For instance,
3599 maint packet heythere
3601 sends the packet "$heythere#<checksum>". Note that it is very easy to
3602 disrupt a debugging session by sending the wrong packet at the wrong
3605 The compare-sections command allows you to compare section data on the
3606 target to what is in the executable file without uploading or
3607 downloading, by comparing CRC checksums.
3609 * Tracing can collect general expressions
3611 You may now collect general expressions at tracepoints. This requires
3612 further additions to the target-side stub; see tracepoint.c and
3613 doc/agentexpr.texi for further details.
3615 * mask-address variable for Mips
3617 For Mips targets, you may control the zeroing of the upper 32 bits of
3618 a 64-bit address by entering `set mask-address on'. This is mainly
3619 of interest to users of embedded R4xxx and R5xxx processors.
3621 * Higher serial baud rates
3623 GDB's serial code now allows you to specify baud rates 57600, 115200,
3624 230400, and 460800 baud. (Note that your host system may not be able
3625 to achieve all of these rates.)
3629 The i960 configuration now includes an initial implementation of a
3630 builtin simulator, contributed by Jim Wilson.
3633 *** Changes in GDB-4.17:
3635 * New native configurations
3637 Alpha GNU/Linux alpha*-*-linux*
3638 Unixware 2.x i[3456]86-unixware2*
3639 Irix 6.x mips*-sgi-irix6*
3640 PowerPC GNU/Linux powerpc-*-linux*
3641 PowerPC Solaris powerpcle-*-solaris*
3642 Sparc GNU/Linux sparc-*-linux*
3643 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3647 Argonaut Risc Chip (ARC) arc-*-*
3648 Hitachi H8/300S h8300*-*-*
3649 Matsushita MN10200 w/simulator mn10200-*-*
3650 Matsushita MN10300 w/simulator mn10300-*-*
3651 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3652 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3653 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3654 Mitsubishi D10V w/simulator d10v-*-*
3655 Mitsubishi M32R/D w/simulator m32r-*-elf*
3656 Tsqware Sparclet sparclet-*-*
3657 NEC V850 w/simulator v850-*-*
3659 * New debugging protocols
3661 ARM with RDI protocol arm*-*-*
3662 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3663 DDB and LSI variants of PMON protocol mips*-*-*
3664 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3665 PowerPC with SDS protocol powerpc{,le}-*-eabi
3666 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3670 All configurations can now understand and use the DWARF 2 debugging
3671 format. The choice is automatic, if the symbol file contains DWARF 2
3676 GDB now includes basic Java language support. This support is
3677 only useful with Java compilers that produce native machine code.
3679 * solib-absolute-prefix and solib-search-path
3681 For SunOS and SVR4 shared libraries, you may now set the prefix for
3682 loading absolute shared library symbol files, and the search path for
3683 locating non-absolute shared library symbol files.
3685 * Live range splitting
3687 GDB can now effectively debug code for which GCC has performed live
3688 range splitting as part of its optimization. See gdb/doc/LRS for
3689 more details on the expected format of the stabs information.
3693 GDB's support for the GNU Hurd, including thread debugging, has been
3694 updated to work with current versions of the Hurd.
3698 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3699 instruction set. ARM GDB automatically detects when Thumb
3700 instructions are in use, and adjusts disassembly and backtracing
3705 GDB's MIPS target configurations now handle the MIP16 16-bit
3710 GDB now includes support for overlays; if an executable has been
3711 linked such that multiple sections are based at the same address, GDB
3712 will decide which section to use for symbolic info. You can choose to
3713 control the decision manually, using overlay commands, or implement
3714 additional target-side support and use "overlay load-target" to bring
3715 in the overlay mapping. Do "help overlay" for more detail.
3719 The command "info symbol <address>" displays information about
3720 the symbol at the specified address.
3724 The standard remote protocol now includes an extension that allows
3725 asynchronous collection and display of trace data. This requires
3726 extensive support in the target-side debugging stub. Tracing mode
3727 includes a new interaction mode in GDB and new commands: see the
3728 file tracepoint.c for more details.
3732 Configurations for embedded MIPS now include a simulator contributed
3733 by Cygnus Solutions. The simulator supports the instruction sets
3734 of most MIPS variants.
3738 Sparc configurations may now include the ERC32 simulator contributed
3739 by the European Space Agency. The simulator is not built into
3740 Sparc targets by default; configure with --enable-sim to include it.
3744 For target configurations that may include multiple variants of a
3745 basic architecture (such as MIPS and SH), you may now set the
3746 architecture explicitly. "set arch" sets, "info arch" lists
3747 the possible architectures.
3749 *** Changes in GDB-4.16:
3751 * New native configurations
3753 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3754 M68K NetBSD m68k-*-netbsd*
3755 PowerPC AIX 4.x powerpc-*-aix*
3756 PowerPC MacOS powerpc-*-macos*
3757 PowerPC Windows NT powerpcle-*-cygwin32
3758 RS/6000 AIX 4.x rs6000-*-aix4*
3762 ARM with RDP protocol arm-*-*
3763 I960 with MON960 i960-*-coff
3764 MIPS VxWorks mips*-*-vxworks*
3765 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3766 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3768 Matra Sparclet sparclet-*-*
3772 The powerpc-eabi configuration now includes the PSIM simulator,
3773 contributed by Andrew Cagney, with assistance from Mike Meissner.
3774 PSIM is a very elaborate model of the PowerPC, including not only
3775 basic instruction set execution, but also details of execution unit
3776 performance and I/O hardware. See sim/ppc/README for more details.
3780 GDB now works with Solaris 2.5.
3782 * Windows 95/NT native
3784 GDB will now work as a native debugger on Windows 95 and Windows NT.
3785 To build it from source, you must use the "gnu-win32" environment,
3786 which uses a DLL to emulate enough of Unix to run the GNU tools.
3787 Further information, binaries, and sources are available at
3788 ftp.cygnus.com, under pub/gnu-win32.
3790 * dont-repeat command
3792 If a user-defined command includes the command `dont-repeat', then the
3793 command will not be repeated if the user just types return. This is
3794 useful if the command is time-consuming to run, so that accidental
3795 extra keystrokes don't run the same command many times.
3797 * Send break instead of ^C
3799 The standard remote protocol now includes an option to send a break
3800 rather than a ^C to the target in order to interrupt it. By default,
3801 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3803 * Remote protocol timeout
3805 The standard remote protocol includes a new variable `remotetimeout'
3806 that allows you to set the number of seconds before GDB gives up trying
3807 to read from the target. The default value is 2.
3809 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3811 By default GDB will automatically keep track of objects as they are
3812 loaded and unloaded by the dynamic linker. By using the command `set
3813 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3814 when shared library events occur, thus allowing you to set breakpoints
3815 in shared libraries which are explicitly loaded by the inferior.
3817 Note this feature does not work on hpux8. On hpux9 you must link
3818 /usr/lib/end.o into your program. This feature should work
3819 automatically on hpux10.
3821 * Irix 5.x hardware watchpoint support
3823 Irix 5 configurations now support the use of hardware watchpoints.
3825 * Mips protocol "SYN garbage limit"
3827 When debugging a Mips target using the `target mips' protocol, you
3828 may set the number of characters that GDB will ignore by setting
3829 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3830 every character. The default value is 1050.
3832 * Recording and replaying remote debug sessions
3834 If you set `remotelogfile' to the name of a file, gdb will write to it
3835 a recording of a remote debug session. This recording may then be
3836 replayed back to gdb using "gdbreplay". See gdbserver/README for
3837 details. This is useful when you have a problem with GDB while doing
3838 remote debugging; you can make a recording of the session and send it
3839 to someone else, who can then recreate the problem.
3841 * Speedups for remote debugging
3843 GDB includes speedups for downloading and stepping MIPS systems using
3844 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3845 and more efficient S-record downloading.
3847 * Memory use reductions and statistics collection
3849 GDB now uses less memory and reports statistics about memory usage.
3850 Try the `maint print statistics' command, for example.
3852 *** Changes in GDB-4.15:
3854 * Psymtabs for XCOFF
3856 The symbol reader for AIX GDB now uses partial symbol tables. This
3857 can greatly improve startup time, especially for large executables.
3859 * Remote targets use caching
3861 Remote targets now use a data cache to speed up communication with the
3862 remote side. The data cache could lead to incorrect results because
3863 it doesn't know about volatile variables, thus making it impossible to
3864 debug targets which use memory mapped I/O devices. `set remotecache
3865 off' turns the the data cache off.
3867 * Remote targets may have threads
3869 The standard remote protocol now includes support for multiple threads
3870 in the target system, using new protocol commands 'H' and 'T'. See
3871 gdb/remote.c for details.
3875 If GDB is configured with `--enable-netrom', then it will include
3876 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3877 acts as though it is a bank of ROM on the target board, but you can
3878 write into it over the network. GDB's support consists only of
3879 support for fast loading into the emulated ROM; to debug, you must use
3880 another protocol, such as standard remote protocol. The usual
3881 sequence is something like
3883 target nrom <netrom-hostname>
3885 target remote <netrom-hostname>:1235
3889 GDB now includes support for the Apple Macintosh, as a host only. It
3890 may be run as either an MPW tool or as a standalone application, and
3891 it can debug through the serial port. All the usual GDB commands are
3892 available, but to the target command, you must supply "serial" as the
3893 device type instead of "/dev/ttyXX". See mpw-README in the main
3894 directory for more information on how to build. The MPW configuration
3895 scripts */mpw-config.in support only a few targets, and only the
3896 mips-idt-ecoff target has been tested.
3900 GDB configuration now uses autoconf. This is not user-visible,
3901 but does simplify configuration and building.
3905 GDB now supports hpux10.
3907 *** Changes in GDB-4.14:
3909 * New native configurations
3911 x86 FreeBSD i[345]86-*-freebsd
3912 x86 NetBSD i[345]86-*-netbsd
3913 NS32k NetBSD ns32k-*-netbsd
3914 Sparc NetBSD sparc-*-netbsd
3918 A29K VxWorks a29k-*-vxworks
3919 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3920 CPU32 EST-300 emulator m68*-*-est*
3921 PowerPC ELF powerpc-*-elf
3924 * Alpha OSF/1 support for procfs
3926 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3927 possible to attach to running processes. As the mounting of the /proc
3928 filesystem is optional on the Alpha, GDB automatically determines
3929 the availability of /proc during startup. This can lead to problems
3930 if /proc is unmounted after GDB has been started.
3932 * Arguments to user-defined commands
3934 User commands may accept up to 10 arguments separated by whitespace.
3935 Arguments are accessed within the user command via $arg0..$arg9. A
3938 print $arg0 + $arg1 + $arg2
3940 To execute the command use:
3943 Defines the command "adder" which prints the sum of its three arguments.
3944 Note the arguments are text substitutions, so they may reference variables,
3945 use complex expressions, or even perform inferior function calls.
3947 * New `if' and `while' commands
3949 This makes it possible to write more sophisticated user-defined
3950 commands. Both commands take a single argument, which is the
3951 expression to evaluate, and must be followed by the commands to
3952 execute, one per line, if the expression is nonzero, the list being
3953 terminated by the word `end'. The `if' command list may include an
3954 `else' word, which causes the following commands to be executed only
3955 if the expression is zero.
3957 * Fortran source language mode
3959 GDB now includes partial support for Fortran 77. It will recognize
3960 Fortran programs and can evaluate a subset of Fortran expressions, but
3961 variables and functions may not be handled correctly. GDB will work
3962 with G77, but does not yet know much about symbols emitted by other
3965 * Better HPUX support
3967 Most debugging facilities now work on dynamic executables for HPPAs
3968 running hpux9 or later. You can attach to running dynamically linked
3969 processes, but by default the dynamic libraries will be read-only, so
3970 for instance you won't be able to put breakpoints in them. To change
3971 that behavior do the following before running the program:
3977 This will cause the libraries to be mapped private and read-write.
3978 To revert to the normal behavior, do this:
3984 You cannot set breakpoints or examine data in the library until after
3985 the library is loaded if the function/data symbols do not have
3988 GDB can now also read debug symbols produced by the HP C compiler on
3989 HPPAs (sorry, no C++, Fortran or 68k support).
3991 * Target byte order now dynamically selectable
3993 You can choose which byte order to use with a target system, via the
3994 commands "set endian big" and "set endian little", and you can see the
3995 current setting by using "show endian". You can also give the command
3996 "set endian auto", in which case GDB will use the byte order
3997 associated with the executable. Currently, only embedded MIPS
3998 configurations support dynamic selection of target byte order.
4000 * New DOS host serial code
4002 This version uses DPMI interrupts to handle buffered I/O, so you
4003 no longer need to run asynctsr when debugging boards connected to
4006 *** Changes in GDB-4.13:
4008 * New "complete" command
4010 This lists all the possible completions for the rest of the line, if it
4011 were to be given as a command itself. This is intended for use by emacs.
4013 * Trailing space optional in prompt
4015 "set prompt" no longer adds a space for you after the prompt you set. This
4016 allows you to set a prompt which ends in a space or one that does not.
4018 * Breakpoint hit counts
4020 "info break" now displays a count of the number of times the breakpoint
4021 has been hit. This is especially useful in conjunction with "ignore"; you
4022 can ignore a large number of breakpoint hits, look at the breakpoint info
4023 to see how many times the breakpoint was hit, then run again, ignoring one
4024 less than that number, and this will get you quickly to the last hit of
4027 * Ability to stop printing at NULL character
4029 "set print null-stop" will cause GDB to stop printing the characters of
4030 an array when the first NULL is encountered. This is useful when large
4031 arrays actually contain only short strings.
4033 * Shared library breakpoints
4035 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
4036 breakpoints in shared libraries before the executable is run.
4038 * Hardware watchpoints
4040 There is a new hardware breakpoint for the watch command for sparclite
4041 targets. See gdb/sparclite/hw_breakpoint.note.
4043 Hardware watchpoints are also now supported under GNU/Linux.
4047 Annotations have been added. These are for use with graphical interfaces,
4048 and are still experimental. Currently only gdba.el uses these.
4050 * Improved Irix 5 support
4052 GDB now works properly with Irix 5.2.
4054 * Improved HPPA support
4056 GDB now works properly with the latest GCC and GAS.
4058 * New native configurations
4060 Sequent PTX4 i[34]86-sequent-ptx4
4061 HPPA running OSF/1 hppa*-*-osf*
4062 Atari TT running SVR4 m68*-*-sysv4*
4063 RS/6000 LynxOS rs6000-*-lynxos*
4067 OS/9000 i[34]86-*-os9k
4068 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
4071 * Hitachi SH7000 and E7000-PC ICE support
4073 There is now support for communicating with the Hitachi E7000-PC ICE.
4074 This is available automatically when GDB is configured for the SH.
4078 As usual, a variety of small fixes and improvements, both generic
4079 and configuration-specific. See the ChangeLog for more detail.
4081 *** Changes in GDB-4.12:
4083 * Irix 5 is now supported
4087 GDB-4.12 on the HPPA has a number of changes which make it unable
4088 to debug the output from the currently released versions of GCC and
4089 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
4090 of GCC and GAS, versions of these tools designed to work with GDB-4.12
4091 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
4094 *** Changes in GDB-4.11:
4096 * User visible changes:
4100 The "set remotedebug" option is now consistent between the mips remote
4101 target, remote targets using the gdb-specific protocol, UDI (AMD's
4102 debug protocol for the 29k) and the 88k bug monitor. It is now an
4103 integer specifying a debug level (normally 0 or 1, but 2 means more
4104 debugging info for the mips target).
4106 * DEC Alpha native support
4108 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
4109 debug info, but GDB works fairly well with the DEC compiler and should
4110 work with a future GCC release. See the README file for a few
4111 Alpha-specific notes.
4113 * Preliminary thread implementation
4115 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
4117 * LynxOS native and target support for 386
4119 This release has been hosted on LynxOS 2.2, and also can be configured
4120 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
4123 * Improvements in C++ mangling/demangling.
4125 This release has much better g++ debugging, specifically in name
4126 mangling/demangling, virtual function calls, print virtual table,
4127 call methods, ...etc.
4129 *** Changes in GDB-4.10:
4131 * User visible changes:
4133 Remote debugging using the GDB-specific (`target remote') protocol now
4134 supports the `load' command. This is only useful if you have some
4135 other way of getting the stub to the target system, and you can put it
4136 somewhere in memory where it won't get clobbered by the download.
4138 Filename completion now works.
4140 When run under emacs mode, the "info line" command now causes the
4141 arrow to point to the line specified. Also, "info line" prints
4142 addresses in symbolic form (as well as hex).
4144 All vxworks based targets now support a user settable option, called
4145 vxworks-timeout. This option represents the number of seconds gdb
4146 should wait for responses to rpc's. You might want to use this if
4147 your vxworks target is, perhaps, a slow software simulator or happens
4148 to be on the far side of a thin network line.
4152 This release contains support for using a DEC alpha as a GDB host for
4153 cross debugging. Native alpha debugging is not supported yet.
4156 *** Changes in GDB-4.9:
4160 This is the first GDB release which is accompanied by a matching testsuite.
4161 The testsuite requires installation of dejagnu, which should be available
4162 via ftp from most sites that carry GNU software.
4166 'Cfront' style demangling has had its name changed to 'ARM' style, to
4167 emphasize that it was written from the specifications in the C++ Annotated
4168 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
4169 disclaimers, it still generated too much confusion with users attempting to
4170 use gdb with AT&T cfront.
4174 GDB now uses a standard remote interface to a simulator library.
4175 So far, the library contains simulators for the Zilog Z8001/2, the
4176 Hitachi H8/300, H8/500 and Super-H.
4178 * New targets supported
4180 H8/300 simulator h8300-hitachi-hms or h8300hms
4181 H8/500 simulator h8500-hitachi-hms or h8500hms
4182 SH simulator sh-hitachi-hms or sh
4183 Z8000 simulator z8k-zilog-none or z8ksim
4184 IDT MIPS board over serial line mips-idt-ecoff
4186 Cross-debugging to GO32 targets is supported. It requires a custom
4187 version of the i386-stub.c module which is integrated with the
4188 GO32 memory extender.
4190 * New remote protocols
4192 MIPS remote debugging protocol.
4194 * New source languages supported
4196 This version includes preliminary support for Chill, a Pascal like language
4197 used by telecommunications companies. Chill support is also being integrated
4198 into the GNU compiler, but we don't know when it will be publically available.
4201 *** Changes in GDB-4.8:
4203 * HP Precision Architecture supported
4205 GDB now supports HP PA-RISC machines running HPUX. A preliminary
4206 version of this support was available as a set of patches from the
4207 University of Utah. GDB does not support debugging of programs
4208 compiled with the HP compiler, because HP will not document their file
4209 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
4210 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
4212 Many problems in the preliminary version have been fixed.
4214 * Faster and better demangling
4216 We have improved template demangling and fixed numerous bugs in the GNU style
4217 demangler. It can now handle type modifiers such as `static' or `const'. Wide
4218 character types (wchar_t) are now supported. Demangling of each symbol is now
4219 only done once, and is cached when the symbol table for a file is read in.
4220 This results in a small increase in memory usage for C programs, a moderate
4221 increase in memory usage for C++ programs, and a fantastic speedup in
4224 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
4225 from the specifications in the Annotated Reference Manual, which AT&T's
4226 compiler does not actually implement.
4228 * G++ multiple inheritance compiler problem
4230 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
4231 inheritance lattices was reworked to properly discover ambiguities. We
4232 recently found an example which causes this new algorithm to fail in a
4233 very subtle way, producing bad debug information for those classes.
4234 The file 'gcc.patch' (in this directory) can be applied to gcc to
4235 circumvent the problem. A future GCC release will contain a complete
4238 The previous G++ debug info problem (mentioned below for the gdb-4.7
4239 release) is fixed in gcc version 2.3.2.
4241 * Improved configure script
4243 The `configure' script will now attempt to guess your system type if
4244 you don't supply a host system type. The old scheme of supplying a
4245 host system triplet is preferable over using this. All the magic is
4246 done in the new `config.guess' script. Examine it for details.
4248 We have also brought our configure script much more in line with the FSF's
4249 version. It now supports the --with-xxx options. In particular,
4250 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
4251 The resulting GDB will not be able to read arbitrary object file formats --
4252 only the format ``expected'' to be used on the configured target system.
4253 We hope to make this the default in a future release.
4255 * Documentation improvements
4257 There's new internal documentation on how to modify GDB, and how to
4258 produce clean changes to the code. We implore people to read it
4259 before submitting changes.
4261 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
4262 M4 macros. The new texinfo.tex is provided in this release. Pre-built
4263 `info' files are also provided. To build `info' files from scratch,
4264 you will need the latest `makeinfo' release, which will be available in
4265 a future texinfo-X.Y release.
4267 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
4268 We're not sure exactly which versions have this problem, but it has
4269 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
4270 or better. If that isn't possible, there is a patch in
4271 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
4272 around this problem.
4276 GDB now supports array constants that can be used in expressions typed in by
4277 the user. The syntax is `{element, element, ...}'. Ie: you can now type
4278 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
4281 The new directory `gdb/sparclite' contains a program that demonstrates
4282 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
4284 * New native hosts supported
4286 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
4287 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
4289 * New targets supported
4291 AMD 29k family via UDI a29k-amd-udi or udi29k
4293 * New file formats supported
4295 BFD now supports reading HP/PA-RISC executables (SOM file format?),
4296 HPUX core files, and SCO 3.2v2 core files.
4300 Attaching to processes now works again; thanks for the many bug reports.
4302 We have also stomped on a bunch of core dumps caused by
4303 printf_filtered("%s") problems.
4305 We eliminated a copyright problem on the rpc and ptrace header files
4306 for VxWorks, which was discovered at the last minute during the 4.7
4307 release. You should now be able to build a VxWorks GDB.
4309 You can now interrupt gdb while an attached process is running. This
4310 will cause the attached process to stop, and give control back to GDB.
4312 We fixed problems caused by using too many file descriptors
4313 for reading symbols from object files and libraries. This was
4314 especially a problem for programs that used many (~100) shared
4317 The `step' command now only enters a subroutine if there is line number
4318 information for the subroutine. Otherwise it acts like the `next'
4319 command. Previously, `step' would enter subroutines if there was
4320 any debugging information about the routine. This avoids problems
4321 when using `cc -g1' on MIPS machines.
4323 * Internal improvements
4325 GDB's internal interfaces have been improved to make it easier to support
4326 debugging of multiple languages in the future.
4328 GDB now uses a common structure for symbol information internally.
4329 Minimal symbols (derived from linkage symbols in object files), partial
4330 symbols (from a quick scan of debug information), and full symbols
4331 contain a common subset of information, making it easier to write
4332 shared code that handles any of them.
4334 * New command line options
4336 We now accept --silent as an alias for --quiet.
4340 The memory-mapped-malloc library is now licensed under the GNU Library
4341 General Public License.
4343 *** Changes in GDB-4.7:
4345 * Host/native/target split
4347 GDB has had some major internal surgery to untangle the support for
4348 hosts and remote targets. Now, when you configure GDB for a remote
4349 target, it will no longer load in all of the support for debugging
4350 local programs on the host. When fully completed and tested, this will
4351 ensure that arbitrary host/target combinations are possible.
4353 The primary conceptual shift is to separate the non-portable code in
4354 GDB into three categories. Host specific code is required any time GDB
4355 is compiled on that host, regardless of the target. Target specific
4356 code relates to the peculiarities of the target, but can be compiled on
4357 any host. Native specific code is everything else: it can only be
4358 built when the host and target are the same system. Child process
4359 handling and core file support are two common `native' examples.
4361 GDB's use of /proc for controlling Unix child processes is now cleaner.
4362 It has been split out into a single module under the `target_ops' vector,
4363 plus two native-dependent functions for each system that uses /proc.
4365 * New hosts supported
4367 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4368 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4369 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4371 * New targets supported
4373 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4374 68030 and CPU32 m68030-*-*, m68332-*-*
4376 * New native hosts supported
4378 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4379 (386bsd is not well tested yet)
4380 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4382 * New file formats supported
4384 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4385 supports reading of `a.out.adobe' object files, which are an a.out
4386 format extended with minimal information about multiple sections.
4390 `show copying' is the same as the old `info copying'.
4391 `show warranty' is the same as `info warrantee'.
4392 These were renamed for consistency. The old commands continue to work.
4394 `info handle' is a new alias for `info signals'.
4396 You can now define pre-command hooks, which attach arbitrary command
4397 scripts to any command. The commands in the hook will be executed
4398 prior to the user's command. You can also create a hook which will be
4399 executed whenever the program stops. See gdb.texinfo.
4403 We now deal with Cfront style name mangling, and can even extract type
4404 info from mangled symbols. GDB can automatically figure out which
4405 symbol mangling style your C++ compiler uses.
4407 Calling of methods and virtual functions has been improved as well.
4411 The crash that occured when debugging Sun Ansi-C compiled binaries is
4412 fixed. This was due to mishandling of the extra N_SO stabs output
4415 We also finally got Ultrix 4.2 running in house, and fixed core file
4416 support, with help from a dozen people on the net.
4418 John M. Farrell discovered that the reason that single-stepping was so
4419 slow on all of the Mips based platforms (primarily SGI and DEC) was
4420 that we were trying to demangle and lookup a symbol used for internal
4421 purposes on every instruction that was being stepped through. Changing
4422 the name of that symbol so that it couldn't be mistaken for a C++
4423 mangled symbol sped things up a great deal.
4425 Rich Pixley sped up symbol lookups in general by getting much smarter
4426 about when C++ symbol mangling is necessary. This should make symbol
4427 completion (TAB on the command line) much faster. It's not as fast as
4428 we'd like, but it's significantly faster than gdb-4.6.
4432 A new user controllable variable 'call_scratch_address' can
4433 specify the location of a scratch area to be used when GDB
4434 calls a function in the target. This is necessary because the
4435 usual method of putting the scratch area on the stack does not work
4436 in systems that have separate instruction and data spaces.
4438 We integrated changes to support the 29k UDI (Universal Debugger
4439 Interface), but discovered at the last minute that we didn't have all
4440 of the appropriate copyright paperwork. We are working with AMD to
4441 resolve this, and hope to have it available soon.
4445 We have sped up the remote serial line protocol, especially for targets
4446 with lots of registers. It now supports a new `expedited status' ('T')
4447 message which can be used in place of the existing 'S' status message.
4448 This allows the remote stub to send only the registers that GDB
4449 needs to make a quick decision about single-stepping or conditional
4450 breakpoints, eliminating the need to fetch the entire register set for
4451 each instruction being stepped through.
4453 The GDB remote serial protocol now implements a write-through cache for
4454 registers, only re-reading the registers if the target has run.
4456 There is also a new remote serial stub for SPARC processors. You can
4457 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4458 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4459 processor with a serial port.
4463 Configure.in files have become much easier to read and modify. A new
4464 `table driven' format makes it more obvious what configurations are
4465 supported, and what files each one uses.
4469 There is a new opcodes library which will eventually contain all of the
4470 disassembly routines and opcode tables. At present, it only contains
4471 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4472 disassembler (binutils/objdump) to share these routines.
4474 The libiberty library is now copylefted under the GNU Library General
4475 Public License. This allows more liberal use, and was done so libg++
4476 can use it. This makes no difference to GDB, since the Library License
4477 grants all the rights from the General Public License.
4481 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4482 reference to the stabs symbol info used by the debugger. It is (as far
4483 as we know) the only published document on this fascinating topic. We
4484 encourage you to read it, compare it to the stabs information on your
4485 system, and send improvements on the document in general (to
4486 bug-gdb@prep.ai.mit.edu).
4488 And, of course, many bugs have been fixed.
4491 *** Changes in GDB-4.6:
4493 * Better support for C++ function names
4495 GDB now accepts as input the "demangled form" of C++ overloaded function
4496 names and member function names, and can do command completion on such names
4497 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4498 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4499 Make use of command completion, it is your friend.
4501 GDB also now accepts a variety of C++ mangled symbol formats. They are
4502 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4503 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4504 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4505 for the list of formats.
4507 * G++ symbol mangling problem
4509 Recent versions of gcc have a bug in how they emit debugging information for
4510 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4511 directory) can be applied to gcc to fix the problem. Alternatively, if you
4512 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4513 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4514 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4517 * New 'maintenance' command
4519 All of the commands related to hacking GDB internals have been moved out of
4520 the main command set, and now live behind the 'maintenance' command. This
4521 can also be abbreviated as 'mt'. The following changes were made:
4523 dump-me -> maintenance dump-me
4524 info all-breakpoints -> maintenance info breakpoints
4525 printmsyms -> maintenance print msyms
4526 printobjfiles -> maintenance print objfiles
4527 printpsyms -> maintenance print psymbols
4528 printsyms -> maintenance print symbols
4530 The following commands are new:
4532 maintenance demangle Call internal GDB demangler routine to
4533 demangle a C++ link name and prints the result.
4534 maintenance print type Print a type chain for a given symbol
4536 * Change to .gdbinit file processing
4538 We now read the $HOME/.gdbinit file before processing the argv arguments
4539 (e.g. reading symbol files or core files). This allows global parameters to
4540 be set, which will apply during the symbol reading. The ./.gdbinit is still
4541 read after argv processing.
4543 * New hosts supported
4545 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4547 GNU/Linux support i386-unknown-linux or linux
4549 We are also including code to support the HP/PA running BSD and HPUX. This
4550 is almost guaranteed not to work, as we didn't have time to test or build it
4551 for this release. We are including it so that the more adventurous (or
4552 masochistic) of you can play with it. We also had major problems with the
4553 fact that the compiler that we got from HP doesn't support the -g option.
4556 * New targets supported
4558 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4560 * More smarts about finding #include files
4562 GDB now remembers the compilation directory for all include files, and for
4563 all files from which C is generated (like yacc and lex sources). This
4564 greatly improves GDB's ability to find yacc/lex sources, and include files,
4565 especially if you are debugging your program from a directory different from
4566 the one that contains your sources.
4568 We also fixed a bug which caused difficulty with listing and setting
4569 breakpoints in include files which contain C code. (In the past, you had to
4570 try twice in order to list an include file that you hadn't looked at before.)
4572 * Interesting infernals change
4574 GDB now deals with arbitrary numbers of sections, where the symbols for each
4575 section must be relocated relative to that section's landing place in the
4576 target's address space. This work was needed to support ELF with embedded
4577 stabs used by Solaris-2.0.
4579 * Bug fixes (of course!)
4581 There have been loads of fixes for the following things:
4582 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4583 i960, stabs, DOS(GO32), procfs, etc...
4585 See the ChangeLog for details.
4587 *** Changes in GDB-4.5:
4589 * New machines supported (host and target)
4591 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4593 SGI Irix-4.x mips-sgi-irix4 or iris4
4595 * New malloc package
4597 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4598 Mmalloc is capable of handling mutiple heaps of memory. It is also
4599 capable of saving a heap to a file, and then mapping it back in later.
4600 This can be used to greatly speedup the startup of GDB by using a
4601 pre-parsed symbol table which lives in a mmalloc managed heap. For
4602 more details, please read mmalloc/mmalloc.texi.
4606 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4607 'help info proc' for details.
4609 * MIPS ecoff symbol table format
4611 The code that reads MIPS symbol table format is now supported on all hosts.
4612 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4615 * File name changes for MS-DOS
4617 Many files in the config directories have been renamed to make it easier to
4618 support GDB on MS-DOSe systems (which have very restrictive file name
4619 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4620 environment) is close to working but has some remaining problems. Note
4621 that debugging of DOS programs is not supported, due to limitations
4622 in the ``operating system'', but it can be used to host cross-debugging.
4624 * Cross byte order fixes
4626 Many fixes have been made to support cross debugging of Sparc and MIPS
4627 targets from hosts whose byte order differs.
4629 * New -mapped and -readnow options
4631 If memory-mapped files are available on your system through the 'mmap'
4632 system call, you can use the -mapped option on the `file' or
4633 `symbol-file' commands to cause GDB to write the symbols from your
4634 program into a reusable file. If the program you are debugging is
4635 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4636 Future GDB debugging sessions will notice the presence of this file,
4637 and will quickly map in symbol information from it, rather than reading
4638 the symbol table from the executable program. Using the '-mapped'
4639 option in a GDB `file' or `symbol-file' command has the same effect as
4640 starting GDB with the '-mapped' command-line option.
4642 You can cause GDB to read the entire symbol table immediately by using
4643 the '-readnow' option with any of the commands that load symbol table
4644 information (or on the GDB command line). This makes the command
4645 slower, but makes future operations faster.
4647 The -mapped and -readnow options are typically combined in order to
4648 build a `fred.syms' file that contains complete symbol information.
4649 A simple GDB invocation to do nothing but build a `.syms' file for future
4652 gdb -batch -nx -mapped -readnow programname
4654 The `.syms' file is specific to the host machine on which GDB is run.
4655 It holds an exact image of GDB's internal symbol table. It cannot be
4656 shared across multiple host platforms.
4658 * longjmp() handling
4660 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4661 siglongjmp() without losing control. This feature has not yet been ported to
4662 all systems. It currently works on many 386 platforms, all MIPS-based
4663 platforms (SGI, DECstation, etc), and Sun3/4.
4667 Preliminary work has been put in to support the new Solaris OS from Sun. At
4668 this time, it can control and debug processes, but it is not capable of
4673 As always, many many bug fixes. The major areas were with g++, and mipsread.
4674 People using the MIPS-based platforms should experience fewer mysterious
4675 crashes and trashed symbol tables.
4677 *** Changes in GDB-4.4:
4679 * New machines supported (host and target)
4681 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4683 BSD Reno on Vax vax-dec-bsd
4684 Ultrix on Vax vax-dec-ultrix
4686 * New machines supported (target)
4688 AMD 29000 embedded, using EBMON a29k-none-none
4692 GDB continues to improve its handling of C++. `References' work better.
4693 The demangler has also been improved, and now deals with symbols mangled as
4694 per the Annotated C++ Reference Guide.
4696 GDB also now handles `stabs' symbol information embedded in MIPS
4697 `ecoff' symbol tables. Since the ecoff format was not easily
4698 extensible to handle new languages such as C++, this appeared to be a
4699 good way to put C++ debugging info into MIPS binaries. This option
4700 will be supported in the GNU C compiler, version 2, when it is
4703 * New features for SVR4
4705 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4706 shared libraries. Debugging dynamically linked programs should present
4707 only minor differences from debugging statically linked programs.
4709 The `info proc' command will print out information about any process
4710 on an SVR4 system (including the one you are debugging). At the moment,
4711 it prints the address mappings of the process.
4713 If you bring up GDB on another SVR4 system, please send mail to
4714 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4716 * Better dynamic linking support in SunOS
4718 Reading symbols from shared libraries which contain debugging symbols
4719 now works properly. However, there remain issues such as automatic
4720 skipping of `transfer vector' code during function calls, which
4721 make it harder to debug code in a shared library, than to debug the
4722 same code linked statically.
4726 GDB is now using the latest `getopt' routines from the FSF. This
4727 version accepts the -- prefix for options with long names. GDB will
4728 continue to accept the old forms (-option and +option) as well.
4729 Various single letter abbreviations for options have been explicity
4730 added to the option table so that they won't get overshadowed in the
4731 future by other options that begin with the same letter.
4735 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4736 Many assorted bugs have been handled. Many more remain to be handled.
4737 See the various ChangeLog files (primarily in gdb and bfd) for details.
4740 *** Changes in GDB-4.3:
4742 * New machines supported (host and target)
4744 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4745 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4746 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4748 * Almost SCO Unix support
4750 We had hoped to support:
4751 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4752 (except for core file support), but we discovered very late in the release
4753 that it has problems with process groups that render gdb unusable. Sorry
4754 about that. I encourage people to fix it and post the fixes.
4756 * Preliminary ELF and DWARF support
4758 GDB can read ELF object files on System V Release 4, and can handle
4759 debugging records for C, in DWARF format, in ELF files. This support
4760 is preliminary. If you bring up GDB on another SVR4 system, please
4761 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4766 GDB now uses the latest `readline' library. One user-visible change
4767 is that two tabs will list possible command completions, which previously
4768 required typing M-? (meta-question mark, or ESC ?).
4772 The `stepi' bug that many of you noticed has been squashed.
4773 Many bugs in C++ have been handled. Many more remain to be handled.
4774 See the various ChangeLog files (primarily in gdb and bfd) for details.
4776 * State of the MIPS world (in case you wondered):
4778 GDB can understand the symbol tables emitted by the compilers
4779 supplied by most vendors of MIPS-based machines, including DEC. These
4780 symbol tables are in a format that essentially nobody else uses.
4782 Some versions of gcc come with an assembler post-processor called
4783 mips-tfile. This program is required if you want to do source-level
4784 debugging of gcc-compiled programs. I believe FSF does not ship
4785 mips-tfile with gcc version 1, but it will eventually come with gcc
4788 Debugging of g++ output remains a problem. g++ version 1.xx does not
4789 really support it at all. (If you're lucky, you should be able to get
4790 line numbers and stack traces to work, but no parameters or local
4791 variables.) With some work it should be possible to improve the
4794 When gcc version 2 is released, you will have somewhat better luck.
4795 However, even then you will get confusing results for inheritance and
4798 We will eventually provide full debugging of g++ output on
4799 DECstations. This will probably involve some kind of stabs-in-ecoff
4800 encapulation, but the details have not been worked out yet.
4803 *** Changes in GDB-4.2:
4805 * Improved configuration
4807 Only one copy of `configure' exists now, and it is not self-modifying.
4808 Porting BFD is simpler.
4812 The `step' and `next' commands now only stop at the first instruction
4813 of a source line. This prevents the multiple stops that used to occur
4814 in switch statements, for-loops, etc. `Step' continues to stop if a
4815 function that has debugging information is called within the line.
4819 Lots of small bugs fixed. More remain.
4821 * New host supported (not target)
4823 Intel 386 PC clone running Mach i386-none-mach
4826 *** Changes in GDB-4.1:
4828 * Multiple source language support
4830 GDB now has internal scaffolding to handle several source languages.
4831 It determines the type of each source file from its filename extension,
4832 and will switch expression parsing and number formatting to match the
4833 language of the function in the currently selected stack frame.
4834 You can also specifically set the language to be used, with
4835 `set language c' or `set language modula-2'.
4839 GDB now has preliminary support for the GNU Modula-2 compiler,
4840 currently under development at the State University of New York at
4841 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4842 continue through the fall of 1991 and into 1992.
4844 Other Modula-2 compilers are currently not supported, and attempting to
4845 debug programs compiled with them will likely result in an error as the
4846 symbol table is read. Feel free to work on it, though!
4848 There are hooks in GDB for strict type checking and range checking,
4849 in the `Modula-2 philosophy', but they do not currently work.
4853 GDB can now write to executable and core files (e.g. patch
4854 a variable's value). You must turn this switch on, specify
4855 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4856 by assigning a new value to a variable. Modifications take
4859 * Automatic SunOS shared library reading
4861 When you run your program, GDB automatically determines where its
4862 shared libraries (if any) have been loaded, and reads their symbols.
4863 The `share' command is no longer needed. This also works when
4864 examining core files.
4868 You can specify the number of lines that the `list' command shows.
4871 * New machines supported (host and target)
4873 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4874 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4875 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4877 * New hosts supported (not targets)
4879 IBM RT/PC: romp-ibm-aix or rtpc
4881 * New targets supported (not hosts)
4883 AMD 29000 embedded with COFF a29k-none-coff
4884 AMD 29000 embedded with a.out a29k-none-aout
4885 Ultracomputer remote kernel debug a29k-nyu-kern
4887 * New remote interfaces
4893 *** Changes in GDB-4.0:
4897 Wide output is wrapped at good places to make the output more readable.
4899 Gdb now supports cross-debugging from a host machine of one type to a
4900 target machine of another type. Communication with the target system
4901 is over serial lines. The ``target'' command handles connecting to the
4902 remote system; the ``load'' command will download a program into the
4903 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4904 also supports debugging of realtime processes running under VxWorks,
4905 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4906 stub on the target system.
4908 New CPUs supported include the AMD 29000 and Intel 960.
4910 GDB now reads object files and symbol tables via a ``binary file''
4911 library, which allows a single copy of GDB to debug programs of multiple
4912 object file types such as a.out and coff.
4914 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4915 refcard.dvi and refcard.ps are available to format it).
4918 * Control-Variable user interface simplified
4920 All variables that control the operation of the debugger can be set
4921 by the ``set'' command, and displayed by the ``show'' command.
4923 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4924 ``Show prompt'' produces the response:
4925 Gdb's prompt is new-gdb=>.
4927 What follows are the NEW set commands. The command ``help set'' will
4928 print a complete list of old and new set commands. ``help set FOO''
4929 will give a longer description of the variable FOO. ``show'' will show
4930 all of the variable descriptions and their current settings.
4932 confirm on/off: Enables warning questions for operations that are
4933 hard to recover from, e.g. rerunning the program while
4934 it is already running. Default is ON.
4936 editing on/off: Enables EMACS style command line editing
4937 of input. Previous lines can be recalled with
4938 control-P, the current line can be edited with control-B,
4939 you can search for commands with control-R, etc.
4942 history filename NAME: NAME is where the gdb command history
4943 will be stored. The default is .gdb_history,
4944 or the value of the environment variable
4947 history size N: The size, in commands, of the command history. The
4948 default is 256, or the value of the environment variable
4951 history save on/off: If this value is set to ON, the history file will
4952 be saved after exiting gdb. If set to OFF, the
4953 file will not be saved. The default is OFF.
4955 history expansion on/off: If this value is set to ON, then csh-like
4956 history expansion will be performed on
4957 command line input. The default is OFF.
4959 radix N: Sets the default radix for input and output. It can be set
4960 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4961 in the current radix, so "set radix 10" is always a no-op.
4963 height N: This integer value is the number of lines on a page. Default
4964 is 24, the current `stty rows'' setting, or the ``li#''
4965 setting from the termcap entry matching the environment
4968 width N: This integer value is the number of characters on a line.
4969 Default is 80, the current `stty cols'' setting, or the ``co#''
4970 setting from the termcap entry matching the environment
4973 Note: ``set screensize'' is obsolete. Use ``set height'' and
4974 ``set width'' instead.
4976 print address on/off: Print memory addresses in various command displays,
4977 such as stack traces and structure values. Gdb looks
4978 more ``symbolic'' if you turn this off; it looks more
4979 ``machine level'' with it on. Default is ON.
4981 print array on/off: Prettyprint arrays. New convenient format! Default
4984 print demangle on/off: Print C++ symbols in "source" form if on,
4987 print asm-demangle on/off: Same, for assembler level printouts
4990 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4993 * Support for Epoch Environment.
4995 The epoch environment is a version of Emacs v18 with windowing. One
4996 new command, ``inspect'', is identical to ``print'', except that if you
4997 are running in the epoch environment, the value is printed in its own
5001 * Support for Shared Libraries
5003 GDB can now debug programs and core files that use SunOS shared libraries.
5004 Symbols from a shared library cannot be referenced
5005 before the shared library has been linked with the program (this
5006 happens after you type ``run'' and before the function main() is entered).
5007 At any time after this linking (including when examining core files
5008 from dynamically linked programs), gdb reads the symbols from each
5009 shared library when you type the ``sharedlibrary'' command.
5010 It can be abbreviated ``share''.
5012 sharedlibrary REGEXP: Load shared object library symbols for files
5013 matching a unix regular expression. No argument
5014 indicates to load symbols for all shared libraries.
5016 info sharedlibrary: Status of loaded shared libraries.
5021 A watchpoint stops execution of a program whenever the value of an
5022 expression changes. Checking for this slows down execution
5023 tremendously whenever you are in the scope of the expression, but is
5024 quite useful for catching tough ``bit-spreader'' or pointer misuse
5025 problems. Some machines such as the 386 have hardware for doing this
5026 more quickly, and future versions of gdb will use this hardware.
5028 watch EXP: Set a watchpoint (breakpoint) for an expression.
5030 info watchpoints: Information about your watchpoints.
5032 delete N: Deletes watchpoint number N (same as breakpoints).
5033 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
5034 enable N: Re-enables watchpoint number N (same as breakpoints).
5037 * C++ multiple inheritance
5039 When used with a GCC version 2 compiler, GDB supports multiple inheritance
5042 * C++ exception handling
5044 Gdb now supports limited C++ exception handling. Besides the existing
5045 ability to breakpoint on an exception handler, gdb can breakpoint on
5046 the raising of an exception (before the stack is peeled back to the
5049 catch FOO: If there is a FOO exception handler in the dynamic scope,
5050 set a breakpoint to catch exceptions which may be raised there.
5051 Multiple exceptions (``catch foo bar baz'') may be caught.
5053 info catch: Lists all exceptions which may be caught in the
5054 current stack frame.
5057 * Minor command changes
5059 The command ``call func (arg, arg, ...)'' now acts like the print
5060 command, except it does not print or save a value if the function's result
5061 is void. This is similar to dbx usage.
5063 The ``up'' and ``down'' commands now always print the frame they end up
5064 at; ``up-silently'' and `down-silently'' can be used in scripts to change
5065 frames without printing.
5067 * New directory command
5069 'dir' now adds directories to the FRONT of the source search path.
5070 The path starts off empty. Source files that contain debug information
5071 about the directory in which they were compiled can be found even
5072 with an empty path; Sun CC and GCC include this information. If GDB can't
5073 find your source file in the current directory, type "dir .".
5075 * Configuring GDB for compilation
5077 For normal use, type ``./configure host''. See README or gdb.texinfo
5080 GDB now handles cross debugging. If you are remotely debugging between
5081 two different machines, type ``./configure host -target=targ''.
5082 Host is the machine where GDB will run; targ is the machine
5083 where the program that you are debugging will run.