1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.3
6 * 'thread-exited' event is now available in the annotations interface.
8 * New built-in convenience variables $_gdb_major and $_gdb_minor
9 provide the GDB version. They are handy for conditionally using
10 features available only in or since specific GDB versions, in
11 scripts that should work error-free with many different versions,
12 such as in system-wide init files.
14 * GDB now supports Thread Local Storage (TLS) variables on several
15 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
16 architectures require kernel changes. TLS is not yet supported for
17 amd64 and i386 process core dumps.
19 * Support for Pointer Authentication on AArch64 Linux.
21 * Two new convenience functions $_cimag and $_creal that extract the
22 imaginary and real parts respectively from complex numbers.
24 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
25 provide the exitcode or exit status of the shell commands launched by
26 GDB commands such as "shell", "pipe" and "make".
30 ** The gdb.Value type has a new method 'format_string' which returns a
31 string representing the value. The formatting is controlled by the
32 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
33 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
34 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
36 ** gdb.Type has a new property 'objfile' which returns the objfile the
41 | [COMMAND] | SHELL_COMMAND
42 | -d DELIM COMMAND DELIM SHELL_COMMAND
43 pipe [COMMAND] | SHELL_COMMAND
44 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
45 Executes COMMAND and sends its output to SHELL_COMMAND.
46 With no COMMAND, repeat the last executed command
47 and send its output to SHELL_COMMAND.
49 set may-call-functions [on|off]
50 show may-call-functions
51 This controls whether GDB will attempt to call functions in
52 the program, such as with expressions in the print command. It
53 defaults to on. Calling functions in the program being debugged
54 can have undesired side effects. It is now possible to forbid
55 such function calls. If function calls are forbidden, GDB will throw
56 an error when a command (such as print expression) calls a function
59 set print finish [on|off]
61 This controls whether the `finish' command will display the value
62 that is returned by the current function. When `off', the value is
63 still entered into the value history, but it is not printed. The
68 Allows deeply nested structures to be simplified when printing by
69 replacing deeply nested parts (beyond the max-depth) with ellipses.
70 The default max-depth is 20, but this can be set to unlimited to get
71 the old behavior back.
73 set logging debugredirect [on|off]
74 By default, GDB debug output will go to both the terminal and the logfile.
75 Set if you want debug output to go only to the log file.
77 set style title foreground COLOR
78 set style title background COLOR
79 set style title intensity VALUE
80 Control the styling of titles.
82 set style highlight foreground COLOR
83 set style highlight background COLOR
84 set style highlight intensity VALUE
85 Control the styling of highlightings.
87 maint set test-settings KIND
88 maint show test-settings KIND
89 A set of commands used by the testsuite for exercising the settings
95 The "help" command uses the title style to enhance the
96 readibility of its output by styling the classes and
100 Similarly to "help", the "apropos" command also uses the
101 title style for the command names. "apropos" accepts now
102 a flag "-v" (verbose) to show the full documentation
103 of matching commands and to use the highlight style to mark
104 the documentation parts matching REGEXP.
107 The "show style" and its subcommands are now styling
108 a style name in their output using its own style, to help
109 the user visualize the different styles.
111 set print raw-frame-arguments
112 show print raw-frame-arguments
114 These commands replace the similarly-named "set/show print raw
115 frame-arguments" commands (now with a dash instead of a space). The
116 old commands are now deprecated and may be removed in a future
119 maint test-options require-delimiter
120 maint test-options unknown-is-error
121 maint test-options unknown-is-operand
122 maint show test-options-completion-result
123 Commands used by the testsuite to validate the command options
126 * New command options, command completion
128 GDB now has a standard infrastructure to support dash-style command
129 options ('-OPT'). One benefit is that commands that use it can
130 easily support completion of command line arguments. Try "CMD
131 -[TAB]" or "help CMD" to find options supported by a command. Over
132 time, we intend to migrate most commands to this infrastructure. A
133 number of commands got support for new command options in this
136 ** The "print" and "compile print" commands now support a number of
137 options that allow overriding relevant global print settings as
138 set by "set print" subcommands:
142 -array-indexes [on|off]
143 -elements NUMBER|unlimited
147 -repeats NUMBER|unlimited
148 -static-members [on|off]
153 Note that because the "print"/"compile print" commands accept
154 arbitrary expressions which may look like options (including
155 abbreviations), if you specify any command option, then you must
156 use a double dash ("--") to mark the end of argument processing.
158 ** The "backtrace" command now supports a number of options that
159 allow overriding relevant global print settings as set by "set
160 backtrace" and "set print" subcommands:
162 -entry-values no|only|preferred|if-needed|both|compact|default
163 -frame-arguments all|scalars|none
164 -raw-frame-arguments [on|off]
168 In addition, the full/no-filters/hide qualifiers are now also
169 exposed as command options too:
175 ** The "frame apply", "tfaas" and "faas" commands similarly now
176 support the following options:
181 All options above can also be abbreviated. The argument of boolean
182 (on/off) options can be 0/1 too, and also the argument is assumed
183 "on" if omitted. This allows writing compact command invocations,
186 (gdb) p -r -p -o 0 -- *myptr
188 The above is equivalent to:
190 (gdb) print -raw -pretty -object off -- *myptr
192 * Completion improvements
194 ** GDB can now complete the options of the "thread apply all" and
195 "taas" commands, and their "-ascending" option can now be
198 ** GDB can now complete the options of the "info threads" command.
200 ** GDB can now complete the options of the "compile file" and
201 "compile code" commands. The "compile file" command now
202 completes on filenames.
204 ** GDB can now complete the backtrace command's
205 "full/no-filters/hide" qualifiers.
207 * In settings, you can now abbreviate "unlimited".
209 E.g., "set print elements u" is now equivalent to "set print
215 This lists all the possible completions for the rest of the line, if it
216 were to be given as a command itself. This is intended for use by MI
217 frontends in cases when separate CLI and MI channels cannot be used.
219 -catch-throw, -catch-rethrow, and -catch-catch
220 These can be used to catch C++ exceptions in a similar fashion to
221 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
225 The testsuite now creates the files gdb.cmd (containing the arguments
226 used to launch GDB) and gdb.in (containing all the commands sent to
227 GDB) in the output directory for each test script. Multiple invocations
228 are appended with .1, .2, .3 etc.
230 *** Changes in GDB 8.3
232 * GDB and GDBserver now support access to additional registers on
233 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
236 * GDB now has experimental support for the compilation and injection of
237 C++ source code into the inferior. This beta release does not include
238 support for several language features, such as templates, constructors,
241 This feature requires GCC 7.1 or higher built with libcp1.so
244 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
245 can be passed using the '[ADDRESS]:PORT' notation, or the regular
246 'ADDRESS:PORT' method.
248 * DWARF index cache: GDB can now automatically save indices of DWARF
249 symbols on disk to speed up further loading of the same binaries.
251 * Ada task switching is now supported on aarch64-elf targets when
252 debugging a program using the Ravenscar Profile. For more information,
253 see the "Tasking Support when using the Ravenscar Profile" section
254 in the GDB user manual.
256 * GDB in batch mode now exits with status 1 if the last command to be
259 * The RISC-V target now supports target descriptions.
261 * System call catchpoints now support system call aliases on FreeBSD.
262 When the ABI of a system call changes in FreeBSD, this is
263 implemented by leaving a compatibility system call using the old ABI
264 at the existing number and allocating a new system call number for
265 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
266 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
267 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
268 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
269 so that a system call catchpoint for the 'kevent' system call will
270 catch invocations of both the 'kevent' and 'freebsd11_kevent'
271 binaries. This ensures that 'kevent' system calls are caught for
272 binaries using either the old or new ABIs.
274 * Terminal styling is now available for the CLI and the TUI. GNU
275 Source Highlight can additionally be used to provide styling of
276 source code snippets. See the "set style" commands, below, for more
279 * Removed support for old demangling styles arm, edg, gnu, hp and
284 set debug compile-cplus-types
285 show debug compile-cplus-types
286 Control the display of debug output about type conversion in the
287 C++ compile feature. Commands have no effect while compiliong
292 Control whether debug output about files/functions skipping is
295 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
296 Apply a command to some frames.
297 FLAG arguments allow to control what output to produce and how to handle
298 errors raised when applying COMMAND to a frame.
301 Apply a command to all threads (ignoring errors and empty output).
302 Shortcut for 'thread apply all -s COMMAND'.
305 Apply a command to all frames (ignoring errors and empty output).
306 Shortcut for 'frame apply all -s COMMAND'.
309 Apply a command to all frames of all threads (ignoring errors and empty
311 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
313 maint set dwarf unwinders (on|off)
314 maint show dwarf unwinders
315 Control whether DWARF unwinders can be used.
318 Display a list of open files for a process.
322 Changes to the "frame", "select-frame", and "info frame" CLI commands.
323 These commands all now take a frame specification which
324 is either a frame level, or one of the keywords 'level', 'address',
325 'function', or 'view' followed by a parameter. Selecting a frame by
326 address, or viewing a frame outside the current backtrace now
327 requires the use of a keyword. Selecting a frame by level is
328 unchanged. The MI comment "-stack-select-frame" is unchanged.
330 target remote FILENAME
331 target extended-remote FILENAME
332 If FILENAME is a Unix domain socket, GDB will attempt to connect
333 to this socket instead of opening FILENAME as a character device.
335 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
336 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
337 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
338 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
339 These commands can now print only the searched entities
340 matching the provided regexp(s), giving a condition
341 on the entity names or entity types. The flag -q disables
342 printing headers or informations messages.
348 These commands now determine the syntax for the shown entities
349 according to the language chosen by `set language'. In particular,
350 `set language auto' means to automatically choose the language of
353 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
354 The 'thread apply' command accepts new FLAG arguments.
355 FLAG arguments allow to control what output to produce and how to handle
356 errors raised when applying COMMAND to a thread.
358 set tui tab-width NCHARS
359 show tui tab-width NCHARS
360 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
362 set style enabled [on|off]
364 Enable or disable terminal styling. Styling is enabled by default
365 on most hosts, but disabled by default when in batch mode.
367 set style sources [on|off]
369 Enable or disable source code styling. Source code styling is
370 enabled by default, but only takes effect if styling in general is
371 enabled, and if GDB was linked with GNU Source Highlight.
373 set style filename foreground COLOR
374 set style filename background COLOR
375 set style filename intensity VALUE
376 Control the styling of file names.
378 set style function foreground COLOR
379 set style function background COLOR
380 set style function intensity VALUE
381 Control the styling of function names.
383 set style variable foreground COLOR
384 set style variable background COLOR
385 set style variable intensity VALUE
386 Control the styling of variable names.
388 set style address foreground COLOR
389 set style address background COLOR
390 set style address intensity VALUE
391 Control the styling of addresses.
395 ** The default version of the MI interpreter is now 3 (-i=mi3).
397 ** The '-data-disassemble' MI command now accepts an '-a' option to
398 disassemble the whole function surrounding the given program
399 counter value or function name. Support for this feature can be
400 verified by using the "-list-features" command, which should
401 contain "data-disassemble-a-option".
403 ** Command responses and notifications that include a frame now include
404 the frame's architecture in a new "arch" attribute.
406 ** The output of information about multi-location breakpoints (which is
407 syntactically incorrect in MI 2) has changed in MI 3. This affects
408 the following commands and events:
412 - =breakpoint-created
413 - =breakpoint-modified
415 The -fix-multi-location-breakpoint-output command can be used to enable
416 this behavior with previous MI versions.
418 * New native configurations
420 GNU/Linux/RISC-V riscv*-*-linux*
421 FreeBSD/riscv riscv*-*-freebsd*
425 GNU/Linux/RISC-V riscv*-*-linux*
427 CSKY GNU/LINUX csky*-*-linux
428 FreeBSD/riscv riscv*-*-freebsd*
430 GNU/Linux/OpenRISC or1k*-*-linux*
434 GDB no longer supports native debugging on versions of MS-Windows
439 ** GDB no longer supports Python versions less than 2.6.
441 ** The gdb.Inferior type has a new 'progspace' property, which is the program
442 space associated to that inferior.
444 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
445 of objfiles associated to that program space.
447 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
448 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
451 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
452 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
453 correct and did not work properly.
455 ** The gdb.Value type has a new constructor, which is used to construct a
456 gdb.Value from a Python buffer object and a gdb.Type.
462 Enable or disable the undefined behavior sanitizer. This is
463 disabled by default, but passing --enable-ubsan=yes or
464 --enable-ubsan=auto to configure will enable it. Enabling this can
465 cause a performance penalty. The undefined behavior sanitizer was
466 first introduced in GCC 4.9.
468 *** Changes in GDB 8.2
470 * The 'set disassembler-options' command now supports specifying options
473 * The 'symbol-file' command now accepts an '-o' option to add a relative
474 offset to all sections.
476 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
477 a relative offset to all sections, but it allows to override the load
478 address of individual sections using '-s'.
480 * The 'add-symbol-file' command no longer requires the second argument
481 (address of the text section).
483 * The endianness used with the 'set endian auto' mode in the absence of
484 an executable selected for debugging is now the last endianness chosen
485 either by one of the 'set endian big' and 'set endian little' commands
486 or by inferring from the last executable used, rather than the startup
489 * The pager now allows a "c" response, meaning to disable the pager
490 for the rest of the current command.
492 * The commands 'info variables/functions/types' now show the source line
493 numbers of symbol definitions when available.
495 * 'info proc' now works on running processes on FreeBSD systems and core
496 files created on FreeBSD systems.
498 * C expressions can now use _Alignof, and C++ expressions can now use
501 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
502 the vector length while the process is running.
508 Control display of debugging info regarding the FreeBSD native target.
510 set|show varsize-limit
511 This new setting allows the user to control the maximum size of Ada
512 objects being printed when those objects have a variable type,
513 instead of that maximum size being hardcoded to 65536 bytes.
515 set|show record btrace cpu
516 Controls the processor to be used for enabling errata workarounds for
519 maint check libthread-db
520 Run integrity checks on the current inferior's thread debugging
523 maint set check-libthread-db (on|off)
524 maint show check-libthread-db
525 Control whether to run integrity checks on inferior specific thread
526 debugging libraries as they are loaded. The default is not to
531 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
533 ** The commands attached to a breakpoint can be set by assigning to
534 the breakpoint's "commands" field.
536 ** gdb.execute can now execute multi-line gdb commands.
538 ** The new functions gdb.convenience_variable and
539 gdb.set_convenience_variable can be used to get and set the value
540 of convenience variables.
542 ** A gdb.Parameter will no longer print the "set" help text on an
543 ordinary "set"; instead by default a "set" will be silent unless
544 the get_set_string method returns a non-empty string.
548 RiscV ELF riscv*-*-elf
550 * Removed targets and native configurations
552 m88k running OpenBSD m88*-*-openbsd*
553 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
554 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
555 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
557 * Aarch64/Linux hardware watchpoints improvements
559 Hardware watchpoints on unaligned addresses are now properly
560 supported when running Linux kernel 4.10 or higher: read and access
561 watchpoints are no longer spuriously missed, and all watchpoints
562 lengths between 1 and 8 bytes are supported. On older kernels,
563 watchpoints set on unaligned addresses are no longer missed, with
564 the tradeoff that there is a possibility of false hits being
569 --enable-codesign=CERT
570 This can be used to invoke "codesign -s CERT" after building gdb.
571 This option is useful on macOS, where code signing is required for
572 gdb to work properly.
574 --disable-gdbcli has been removed
575 This is now silently accepted, but does nothing.
577 *** Changes in GDB 8.1
579 * GDB now supports dynamically creating arbitrary register groups specified
580 in XML target descriptions. This allows for finer grain grouping of
581 registers on systems with a large amount of registers.
583 * The 'ptype' command now accepts a '/o' flag, which prints the
584 offsets and sizes of fields in a struct, like the pahole(1) tool.
586 * New "--readnever" command line option instructs GDB to not read each
587 symbol file's symbolic debug information. This makes startup faster
588 but at the expense of not being able to perform symbolic debugging.
589 This option is intended for use cases where symbolic debugging will
590 not be used, e.g., when you only need to dump the debuggee's core.
592 * GDB now uses the GNU MPFR library, if available, to emulate target
593 floating-point arithmetic during expression evaluation when the target
594 uses different floating-point formats than the host. At least version
595 3.1 of GNU MPFR is required.
597 * GDB now supports access to the guarded-storage-control registers and the
598 software-based guarded-storage broadcast control registers on IBM z14.
600 * On Unix systems, GDB now supports transmitting environment variables
601 that are to be set or unset to GDBserver. These variables will
602 affect the environment to be passed to the remote inferior.
604 To inform GDB of environment variables that are to be transmitted to
605 GDBserver, use the "set environment" command. Only user set
606 environment variables are sent to GDBserver.
608 To inform GDB of environment variables that are to be unset before
609 the remote inferior is started by the GDBserver, use the "unset
610 environment" command.
612 * Completion improvements
614 ** GDB can now complete function parameters in linespecs and
615 explicit locations without quoting. When setting breakpoints,
616 quoting around functions names to help with TAB-completion is
617 generally no longer necessary. For example, this now completes
620 (gdb) b function(in[TAB]
621 (gdb) b function(int)
623 Related, GDB is no longer confused with completing functions in
624 C++ anonymous namespaces:
627 (gdb) b (anonymous namespace)::[TAB][TAB]
628 (anonymous namespace)::a_function()
629 (anonymous namespace)::b_function()
631 ** GDB now has much improved linespec and explicit locations TAB
632 completion support, that better understands what you're
633 completing and offers better suggestions. For example, GDB no
634 longer offers data symbols as possible completions when you're
635 setting a breakpoint.
637 ** GDB now TAB-completes label symbol names.
639 ** The "complete" command now mimics TAB completion accurately.
641 * New command line options (gcore)
644 Dump all memory mappings.
646 * Breakpoints on C++ functions are now set on all scopes by default
648 By default, breakpoints on functions/methods are now interpreted as
649 specifying all functions with the given name ignoring missing
650 leading scopes (namespaces and classes).
652 For example, assuming a C++ program with symbols named:
657 both commands "break func()" and "break B::func()" set a breakpoint
660 You can use the new flag "-qualified" to override this. This makes
661 GDB interpret the specified function name as a complete
662 fully-qualified name instead. For example, using the same C++
663 program, the "break -q B::func" command sets a breakpoint on
664 "B::func", only. A parameter has been added to the Python
665 gdb.Breakpoint constructor to achieve the same result when creating
666 a breakpoint from Python.
668 * Breakpoints on functions marked with C++ ABI tags
670 GDB can now set breakpoints on functions marked with C++ ABI tags
671 (e.g., [abi:cxx11]). See here for a description of ABI tags:
672 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
674 Functions with a C++11 abi tag are demangled/displayed like this:
676 function[abi:cxx11](int)
679 You can now set a breakpoint on such functions simply as if they had
682 (gdb) b function(int)
684 Or if you need to disambiguate between tags, like:
686 (gdb) b function[abi:other_tag](int)
688 Tab completion was adjusted accordingly as well.
692 ** New events gdb.new_inferior, gdb.inferior_deleted, and
693 gdb.new_thread are emitted. See the manual for further
694 description of these.
696 ** A new function, "gdb.rbreak" has been added to the Python API.
697 This function allows the setting of a large number of breakpoints
698 via a regex pattern in Python. See the manual for further details.
700 ** Python breakpoints can now accept explicit locations. See the
701 manual for a further description of this feature.
704 * New features in the GDB remote stub, GDBserver
706 ** GDBserver is now able to start inferior processes with a
707 specified initial working directory.
709 The user can set the desired working directory to be used from
710 GDB using the new "set cwd" command.
712 ** New "--selftest" command line option runs some GDBserver self
713 tests. These self tests are disabled in releases.
715 ** On Unix systems, GDBserver now does globbing expansion and variable
716 substitution in inferior command line arguments.
718 This is done by starting inferiors using a shell, like GDB does.
719 See "set startup-with-shell" in the user manual for how to disable
720 this from GDB when using "target extended-remote". When using
721 "target remote", you can disable the startup with shell by using the
722 new "--no-startup-with-shell" GDBserver command line option.
724 ** On Unix systems, GDBserver now supports receiving environment
725 variables that are to be set or unset from GDB. These variables
726 will affect the environment to be passed to the inferior.
728 * When catching an Ada exception raised with a message, GDB now prints
729 the message in the catchpoint hit notification. In GDB/MI mode, that
730 information is provided as an extra field named "exception-message"
731 in the *stopped notification.
733 * Trait objects can now be inspected When debugging Rust code. This
734 requires compiler support which will appear in Rust 1.24.
738 QEnvironmentHexEncoded
739 Inform GDBserver of an environment variable that is to be passed to
740 the inferior when starting it.
743 Inform GDBserver of an environment variable that is to be unset
744 before starting the remote inferior.
747 Inform GDBserver that the environment should be reset (i.e.,
748 user-set environment variables should be unset).
751 Indicates whether the inferior must be started with a shell or not.
754 Tell GDBserver that the inferior to be started should use a specific
757 * The "maintenance print c-tdesc" command now takes an optional
758 argument which is the file name of XML target description.
760 * The "maintenance selftest" command now takes an optional argument to
761 filter the tests to be run.
763 * The "enable", and "disable" commands now accept a range of
764 breakpoint locations, e.g. "enable 1.3-5".
769 Set and show the current working directory for the inferior.
772 Set and show compilation command used for compiling and injecting code
773 with the 'compile' commands.
775 set debug separate-debug-file
776 show debug separate-debug-file
777 Control the display of debug output about separate debug file search.
779 set dump-excluded-mappings
780 show dump-excluded-mappings
781 Control whether mappings marked with the VM_DONTDUMP flag should be
782 dumped when generating a core file.
785 List the registered selftests.
788 Start the debugged program stopping at the first instruction.
791 Control display of debugging messages related to OpenRISC targets.
793 set|show print type nested-type-limit
794 Set and show the limit of nesting level for nested types that the
795 type printer will show.
797 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
800 * Safer/improved support for debugging with no debug info
802 GDB no longer assumes functions with no debug information return
805 This means that GDB now refuses to call such functions unless you
806 tell it the function's type, by either casting the call to the
807 declared return type, or by casting the function to a function
808 pointer of the right type, and calling that:
810 (gdb) p getenv ("PATH")
811 'getenv' has unknown return type; cast the call to its declared return type
812 (gdb) p (char *) getenv ("PATH")
813 $1 = 0x7fffffffe "/usr/local/bin:/"...
814 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
815 $2 = 0x7fffffffe "/usr/local/bin:/"...
817 Similarly, GDB no longer assumes that global variables with no debug
818 info have type 'int', and refuses to print the variable's value
819 unless you tell it the variable's type:
822 'var' has unknown type; cast it to its declared type
826 * New native configurations
828 FreeBSD/aarch64 aarch64*-*-freebsd*
829 FreeBSD/arm arm*-*-freebsd*
833 FreeBSD/aarch64 aarch64*-*-freebsd*
834 FreeBSD/arm arm*-*-freebsd*
835 OpenRISC ELF or1k*-*-elf
837 * Removed targets and native configurations
839 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
841 *** Changes in GDB 8.0
843 * GDB now supports access to the PKU register on GNU/Linux. The register is
844 added by the Memory Protection Keys for Userspace feature which will be
845 available in future Intel CPUs.
847 * GDB now supports C++11 rvalue references.
851 ** New functions to start, stop and access a running btrace recording.
852 ** Rvalue references are now supported in gdb.Type.
854 * GDB now supports recording and replaying rdrand and rdseed Intel 64
857 * Building GDB and GDBserver now requires a C++11 compiler.
859 For example, GCC 4.8 or later.
861 It is no longer possible to build GDB or GDBserver with a C
862 compiler. The --disable-build-with-cxx configure option has been
865 * Building GDB and GDBserver now requires GNU make >= 3.81.
867 It is no longer supported to build GDB or GDBserver with another
868 implementation of the make program or an earlier version of GNU make.
870 * Native debugging on MS-Windows supports command-line redirection
872 Command-line arguments used for starting programs on MS-Windows can
873 now include redirection symbols supported by native Windows shells,
874 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
875 as "run", "start", and "set args", as well as the corresponding MI
878 * Support for thread names on MS-Windows.
880 GDB now catches and handles the special exception that programs
881 running on MS-Windows use to assign names to threads in the
884 * Support for Java programs compiled with gcj has been removed.
886 * User commands now accept an unlimited number of arguments.
887 Previously, only up to 10 was accepted.
889 * The "eval" command now expands user-defined command arguments.
891 This makes it easier to process a variable number of arguments:
896 eval "print $arg%d", $i
901 * Target descriptions can now describe registers for sparc32 and sparc64.
903 * GDB now supports DWARF version 5 (debug information format).
904 Its .debug_names index is not yet supported.
906 * New native configurations
908 FreeBSD/mips mips*-*-freebsd
912 Synopsys ARC arc*-*-elf32
913 FreeBSD/mips mips*-*-freebsd
915 * Removed targets and native configurations
917 Alpha running FreeBSD alpha*-*-freebsd*
918 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
923 Erases all the flash memory regions reported by the target.
925 maint print arc arc-instruction address
926 Print internal disassembler information about instruction at a given address.
930 set disassembler-options
931 show disassembler-options
932 Controls the passing of target specific information to the disassembler.
933 If it is necessary to specify more than one disassembler option then
934 multiple options can be placed together into a comma separated list.
935 The default value is the empty string. Currently, the only supported
936 targets are ARM, PowerPC and S/390.
941 Erases all the flash memory regions reported by the target. This is
942 equivalent to the CLI command flash-erase.
944 -file-list-shared-libraries
945 List the shared libraries in the program. This is
946 equivalent to the CLI command "info shared".
949 Catchpoints stopping the program when Ada exceptions are
950 handled. This is equivalent to the CLI command "catch handlers".
952 *** Changes in GDB 7.12
954 * GDB and GDBserver now build with a C++ compiler by default.
956 The --enable-build-with-cxx configure option is now enabled by
957 default. One must now explicitly configure with
958 --disable-build-with-cxx in order to build with a C compiler. This
959 option will be removed in a future release.
961 * GDBserver now supports recording btrace without maintaining an active
964 * GDB now supports a negative repeat count in the 'x' command to examine
965 memory backward from the given address. For example:
968 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
969 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
970 (gdb) x/-5i 0x0000000000400580
971 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
972 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
973 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
974 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
975 0x40057b <main(int, char**)+25>:
976 callq 0x400536 <Func1(int, char const*)>
978 * Fortran: Support structures with fields of dynamic types and
979 arrays of dynamic types.
981 * The symbol dumping maintenance commands have new syntax.
982 maint print symbols [-pc address] [--] [filename]
983 maint print symbols [-objfile objfile] [-source source] [--] [filename]
984 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
985 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
986 maint print msymbols [-objfile objfile] [--] [filename]
988 * GDB now supports multibit bitfields and enums in target register
991 * New Python-based convenience function $_as_string(val), which returns
992 the textual representation of a value. This function is especially
993 useful to obtain the text label of an enum value.
995 * Intel MPX bound violation handling.
997 Segmentation faults caused by a Intel MPX boundary violation
998 now display the kind of violation (upper or lower), the memory
999 address accessed and the memory bounds, along with the usual
1000 signal received and code location.
1004 Program received signal SIGSEGV, Segmentation fault
1005 Upper bound violation while accessing address 0x7fffffffc3b3
1006 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1007 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1009 * Rust language support.
1010 GDB now supports debugging programs written in the Rust programming
1011 language. See https://www.rust-lang.org/ for more information about
1014 * Support for running interpreters on specified input/output devices
1016 GDB now supports a new mechanism that allows frontends to provide
1017 fully featured GDB console views, as a better alternative to
1018 building such views on top of the "-interpreter-exec console"
1019 command. See the new "new-ui" command below. With that command,
1020 frontends can now start GDB in the traditional command-line mode
1021 running in an embedded terminal emulator widget, and create a
1022 separate MI interpreter running on a specified i/o device. In this
1023 way, GDB handles line editing, history, tab completion, etc. in the
1024 console all by itself, and the GUI uses the separate MI interpreter
1025 for its own control and synchronization, invisible to the command
1028 * The "catch syscall" command catches groups of related syscalls.
1030 The "catch syscall" command now supports catching a group of related
1031 syscalls using the 'group:' or 'g:' prefix.
1036 skip -gfile file-glob-pattern
1037 skip -function function
1038 skip -rfunction regular-expression
1039 A generalized form of the skip command, with new support for
1040 glob-style file names and regular expressions for function names.
1041 Additionally, a file spec and a function spec may now be combined.
1043 maint info line-table REGEXP
1044 Display the contents of GDB's internal line table data struture.
1047 Run any GDB unit tests that were compiled in.
1050 Start a new user interface instance running INTERP as interpreter,
1051 using the TTY file for input/output.
1055 ** gdb.Breakpoint objects have a new attribute "pending", which
1056 indicates whether the breakpoint is pending.
1057 ** Three new breakpoint-related events have been added:
1058 gdb.breakpoint_created, gdb.breakpoint_modified, and
1059 gdb.breakpoint_deleted.
1061 signal-event EVENTID
1062 Signal ("set") the given MS-Windows event object. This is used in
1063 conjunction with the Windows JIT debugging (AeDebug) support, where
1064 the OS suspends a crashing process until a debugger can attach to
1065 it. Resuming the crashing process, in order to debug it, is done by
1066 signalling an event.
1068 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1069 was added in GDBserver, including JIT compiling fast tracepoint's
1070 conditional expression bytecode into native code.
1072 * Support for various remote target protocols and ROM monitors has
1075 target m32rsdi Remote M32R debugging over SDI
1076 target mips MIPS remote debugging protocol
1077 target pmon PMON ROM monitor
1078 target ddb NEC's DDB variant of PMON for Vr4300
1079 target rockhopper NEC RockHopper variant of PMON
1080 target lsi LSI variant of PMO
1082 * Support for tracepoints and fast tracepoints on powerpc-linux,
1083 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1084 including JIT compiling fast tracepoint's conditional expression
1085 bytecode into native code.
1087 * MI async record =record-started now includes the method and format used for
1088 recording. For example:
1090 =record-started,thread-group="i1",method="btrace",format="bts"
1092 * MI async record =thread-selected now includes the frame field. For example:
1094 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1098 Andes NDS32 nds32*-*-elf
1100 *** Changes in GDB 7.11
1102 * GDB now supports debugging kernel-based threads on FreeBSD.
1104 * Per-inferior thread numbers
1106 Thread numbers are now per inferior instead of global. If you're
1107 debugging multiple inferiors, GDB displays thread IDs using a
1108 qualified INF_NUM.THR_NUM form. For example:
1112 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1113 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1114 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1115 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1117 As consequence, thread numbers as visible in the $_thread
1118 convenience variable and in Python's InferiorThread.num attribute
1119 are no longer unique between inferiors.
1121 GDB now maintains a second thread ID per thread, referred to as the
1122 global thread ID, which is the new equivalent of thread numbers in
1123 previous releases. See also $_gthread below.
1125 For backwards compatibility, MI's thread IDs always refer to global
1128 * Commands that accept thread IDs now accept the qualified
1129 INF_NUM.THR_NUM form as well. For example:
1132 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1135 * In commands that accept a list of thread IDs, you can now refer to
1136 all threads of an inferior using a star wildcard. GDB accepts
1137 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1138 refer to all threads of the current inferior. For example, "info
1141 * You can use "info threads -gid" to display the global thread ID of
1144 * The new convenience variable $_gthread holds the global number of
1147 * The new convenience variable $_inferior holds the number of the
1150 * GDB now displays the ID and name of the thread that hit a breakpoint
1151 or received a signal, if your program is multi-threaded. For
1154 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1155 Thread 1 "main" received signal SIGINT, Interrupt.
1157 * Record btrace now supports non-stop mode.
1159 * Support for tracepoints on aarch64-linux was added in GDBserver.
1161 * The 'record instruction-history' command now indicates speculative execution
1162 when using the Intel Processor Trace recording format.
1164 * GDB now allows users to specify explicit locations, bypassing
1165 the linespec parser. This feature is also available to GDB/MI
1168 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1169 GDB now is able to debug both AArch64 applications and ARM applications
1172 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1173 including JIT compiling fast tracepoint's conditional expression bytecode
1176 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1178 * "info threads", "info inferiors", "info display", "info checkpoints"
1179 and "maint info program-spaces" now list the corresponding items in
1180 ascending ID order, for consistency with all other "info" commands.
1182 * In Ada, the overloads selection menu has been enhanced to display the
1183 parameter types and the return types for the matching overloaded subprograms.
1187 maint set target-non-stop (on|off|auto)
1188 maint show target-non-stop
1189 Control whether GDB targets always operate in non-stop mode even if
1190 "set non-stop" is "off". The default is "auto", meaning non-stop
1191 mode is enabled if supported by the target.
1193 maint set bfd-sharing
1194 maint show bfd-sharing
1195 Control the reuse of bfd objects.
1198 show debug bfd-cache
1199 Control display of debugging info regarding bfd caching.
1203 Control display of debugging info regarding FreeBSD threads.
1205 set remote multiprocess-extensions-packet
1206 show remote multiprocess-extensions-packet
1207 Set/show the use of the remote protocol multiprocess extensions.
1209 set remote thread-events
1210 show remote thread-events
1211 Set/show the use of thread create/exit events.
1213 set ada print-signatures on|off
1214 show ada print-signatures"
1215 Control whether parameter types and return types are displayed in overloads
1216 selection menus. It is activaled (@code{on}) by default.
1220 Controls the maximum size of memory, in bytes, that GDB will
1221 allocate for value contents. Prevents incorrect programs from
1222 causing GDB to allocate overly large buffers. Default is 64k.
1224 * The "disassemble" command accepts a new modifier: /s.
1225 It prints mixed source+disassembly like /m with two differences:
1226 - disassembled instructions are now printed in program order, and
1227 - and source for all relevant files is now printed.
1228 The "/m" option is now considered deprecated: its "source-centric"
1229 output hasn't proved useful in practice.
1231 * The "record instruction-history" command accepts a new modifier: /s.
1232 It behaves exactly like /m and prints mixed source+disassembly.
1234 * The "set scheduler-locking" command supports a new mode "replay".
1235 It behaves like "off" in record mode and like "on" in replay mode.
1237 * Support for various ROM monitors has been removed:
1239 target dbug dBUG ROM monitor for Motorola ColdFire
1240 target picobug Motorola picobug monitor
1241 target dink32 DINK32 ROM monitor for PowerPC
1242 target m32r Renesas M32R/D ROM monitor
1243 target mon2000 mon2000 ROM monitor
1244 target ppcbug PPCBUG ROM monitor for PowerPC
1246 * Support for reading/writing memory and extracting values on architectures
1247 whose memory is addressable in units of any integral multiple of 8 bits.
1250 Allows to break when an Ada exception is handled.
1252 * New remote packets
1255 Indicates that an exec system call was executed.
1257 exec-events feature in qSupported
1258 The qSupported packet allows GDB to request support for exec
1259 events using the new 'gdbfeature' exec-event, and the qSupported
1260 response can contain the corresponding 'stubfeature'. Set and
1261 show commands can be used to display whether these features are enabled.
1264 Equivalent to interrupting with the ^C character, but works in
1267 thread created stop reason (T05 create:...)
1268 Indicates that the thread was just created and is stopped at entry.
1270 thread exit stop reply (w exitcode;tid)
1271 Indicates that the thread has terminated.
1274 Enables/disables thread create and exit event reporting. For
1275 example, this is used in non-stop mode when GDB stops a set of
1276 threads and synchronously waits for the their corresponding stop
1277 replies. Without exit events, if one of the threads exits, GDB
1278 would hang forever not knowing that it should no longer expect a
1279 stop for that same thread.
1282 Indicates that there are no resumed threads left in the target (all
1283 threads are stopped). The remote stub reports support for this stop
1284 reply to GDB's qSupported query.
1287 Enables/disables catching syscalls from the inferior process.
1288 The remote stub reports support for this packet to GDB's qSupported query.
1290 syscall_entry stop reason
1291 Indicates that a syscall was just called.
1293 syscall_return stop reason
1294 Indicates that a syscall just returned.
1296 * Extended-remote exec events
1298 ** GDB now has support for exec events on extended-remote Linux targets.
1299 For such targets with Linux kernels 2.5.46 and later, this enables
1300 follow-exec-mode and exec catchpoints.
1302 set remote exec-event-feature-packet
1303 show remote exec-event-feature-packet
1304 Set/show the use of the remote exec event feature.
1306 * Thread names in remote protocol
1308 The reply to qXfer:threads:read may now include a name attribute for each
1311 * Target remote mode fork and exec events
1313 ** GDB now has support for fork and exec events on target remote mode
1314 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1315 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1316 fork and exec catchpoints.
1318 * Remote syscall events
1320 ** GDB now has support for catch syscall on remote Linux targets,
1321 currently enabled on x86/x86_64 architectures.
1323 set remote catch-syscall-packet
1324 show remote catch-syscall-packet
1325 Set/show the use of the remote catch syscall feature.
1329 ** The -var-set-format command now accepts the zero-hexadecimal
1330 format. It outputs data in hexadecimal format with zero-padding on the
1335 ** gdb.InferiorThread objects have a new attribute "global_num",
1336 which refers to the thread's global thread ID. The existing
1337 "num" attribute now refers to the thread's per-inferior number.
1338 See "Per-inferior thread numbers" above.
1339 ** gdb.InferiorThread objects have a new attribute "inferior", which
1340 is the Inferior object the thread belongs to.
1342 *** Changes in GDB 7.10
1344 * Support for process record-replay and reverse debugging on aarch64*-linux*
1345 targets has been added. GDB now supports recording of A64 instruction set
1346 including advance SIMD instructions.
1348 * Support for Sun's version of the "stabs" debug file format has been removed.
1350 * GDB now honors the content of the file /proc/PID/coredump_filter
1351 (PID is the process ID) on GNU/Linux systems. This file can be used
1352 to specify the types of memory mappings that will be included in a
1353 corefile. For more information, please refer to the manual page of
1354 "core(5)". GDB also has a new command: "set use-coredump-filter
1355 on|off". It allows to set whether GDB will read the content of the
1356 /proc/PID/coredump_filter file when generating a corefile.
1358 * The "info os" command on GNU/Linux can now display information on
1360 "info os cpus" Listing of all cpus/cores on the system
1362 * GDB has two new commands: "set serial parity odd|even|none" and
1363 "show serial parity". These allows to set or show parity for the
1366 * The "info source" command now displays the producer string if it was
1367 present in the debug info. This typically includes the compiler version
1368 and may include things like its command line arguments.
1370 * The "info dll", an alias of the "info sharedlibrary" command,
1371 is now available on all platforms.
1373 * Directory names supplied to the "set sysroot" commands may be
1374 prefixed with "target:" to tell GDB to access shared libraries from
1375 the target system, be it local or remote. This replaces the prefix
1376 "remote:". The default sysroot has been changed from "" to
1377 "target:". "remote:" is automatically converted to "target:" for
1378 backward compatibility.
1380 * The system root specified by "set sysroot" will be prepended to the
1381 filename of the main executable (if reported to GDB as absolute by
1382 the operating system) when starting processes remotely, and when
1383 attaching to already-running local or remote processes.
1385 * GDB now supports automatic location and retrieval of executable
1386 files from remote targets. Remote debugging can now be initiated
1387 using only a "target remote" or "target extended-remote" command
1388 (no "set sysroot" or "file" commands are required). See "New remote
1391 * The "dump" command now supports verilog hex format.
1393 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1395 * On GNU/Linux, GDB and gdbserver are now able to access executable
1396 and shared library files without a "set sysroot" command when
1397 attaching to processes running in different mount namespaces from
1398 the debugger. This makes it possible to attach to processes in
1399 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1400 See "New remote packets" below.
1402 * The "tui reg" command now provides completion for all of the
1403 available register groups, including target specific groups.
1405 * The HISTSIZE environment variable is no longer read when determining
1406 the size of GDB's command history. GDB now instead reads the dedicated
1407 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1408 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1413 ** Memory ports can now be unbuffered.
1417 ** gdb.Objfile objects have a new attribute "username",
1418 which is the name of the objfile as specified by the user,
1419 without, for example, resolving symlinks.
1420 ** You can now write frame unwinders in Python.
1421 ** gdb.Type objects have a new method "optimized_out",
1422 returning optimized out gdb.Value instance of this type.
1423 ** gdb.Value objects have new methods "reference_value" and
1424 "const_value" which return a reference to the value and a
1425 "const" version of the value respectively.
1429 maint print symbol-cache
1430 Print the contents of the symbol cache.
1432 maint print symbol-cache-statistics
1433 Print statistics of symbol cache usage.
1435 maint flush-symbol-cache
1436 Flush the contents of the symbol cache.
1440 Start branch trace recording using Branch Trace Store (BTS) format.
1443 Evaluate expression by using the compiler and print result.
1447 Explicit commands for enabling and disabling tui mode.
1450 set mpx bound on i386 and amd64
1451 Support for bound table investigation on Intel MPX enabled applications.
1455 Start branch trace recording using Intel Processor Trace format.
1458 Print information about branch tracing internals.
1460 maint btrace packet-history
1461 Print the raw branch tracing data.
1463 maint btrace clear-packet-history
1464 Discard the stored raw branch tracing data.
1467 Discard all branch tracing data. It will be fetched and processed
1468 anew by the next "record" command.
1473 Renamed from "set debug dwarf2-die".
1474 show debug dwarf-die
1475 Renamed from "show debug dwarf2-die".
1477 set debug dwarf-read
1478 Renamed from "set debug dwarf2-read".
1479 show debug dwarf-read
1480 Renamed from "show debug dwarf2-read".
1482 maint set dwarf always-disassemble
1483 Renamed from "maint set dwarf2 always-disassemble".
1484 maint show dwarf always-disassemble
1485 Renamed from "maint show dwarf2 always-disassemble".
1487 maint set dwarf max-cache-age
1488 Renamed from "maint set dwarf2 max-cache-age".
1489 maint show dwarf max-cache-age
1490 Renamed from "maint show dwarf2 max-cache-age".
1492 set debug dwarf-line
1493 show debug dwarf-line
1494 Control display of debugging info regarding DWARF line processing.
1497 show max-completions
1498 Set the maximum number of candidates to be considered during
1499 completion. The default value is 200. This limit allows GDB
1500 to avoid generating large completion lists, the computation of
1501 which can cause the debugger to become temporarily unresponsive.
1503 set history remove-duplicates
1504 show history remove-duplicates
1505 Control the removal of duplicate history entries.
1507 maint set symbol-cache-size
1508 maint show symbol-cache-size
1509 Control the size of the symbol cache.
1511 set|show record btrace bts buffer-size
1512 Set and show the size of the ring buffer used for branch tracing in
1514 The obtained size may differ from the requested size. Use "info
1515 record" to see the obtained buffer size.
1517 set debug linux-namespaces
1518 show debug linux-namespaces
1519 Control display of debugging info regarding Linux namespaces.
1521 set|show record btrace pt buffer-size
1522 Set and show the size of the ring buffer used for branch tracing in
1523 Intel Processor Trace format.
1524 The obtained size may differ from the requested size. Use "info
1525 record" to see the obtained buffer size.
1527 maint set|show btrace pt skip-pad
1528 Set and show whether PAD packets are skipped when computing the
1531 * The command 'thread apply all' can now support new option '-ascending'
1532 to call its specified command for all threads in ascending order.
1534 * Python/Guile scripting
1536 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1537 special section named `.debug_gdb_scripts'.
1539 * New remote packets
1541 qXfer:btrace-conf:read
1542 Return the branch trace configuration for the current thread.
1544 Qbtrace-conf:bts:size
1545 Set the requested ring buffer size for branch tracing in BTS format.
1548 Enable Intel Procesor Trace-based branch tracing for the current
1549 process. The remote stub reports support for this packet to GDB's
1552 Qbtrace-conf:pt:size
1553 Set the requested ring buffer size for branch tracing in Intel Processor
1557 Indicates a memory breakpoint instruction was executed, irrespective
1558 of whether it was GDB that planted the breakpoint or the breakpoint
1559 is hardcoded in the program. This is required for correct non-stop
1563 Indicates the target stopped for a hardware breakpoint. This is
1564 required for correct non-stop mode operation.
1567 Return information about files on the remote system.
1569 qXfer:exec-file:read
1570 Return the full absolute name of the file that was executed to
1571 create a process running on the remote system.
1574 Select the filesystem on which vFile: operations with filename
1575 arguments will operate. This is required for GDB to be able to
1576 access files on remote targets where the remote stub does not
1577 share a common filesystem with the inferior(s).
1580 Indicates that a fork system call was executed.
1583 Indicates that a vfork system call was executed.
1585 vforkdone stop reason
1586 Indicates that a vfork child of the specified process has executed
1587 an exec or exit, allowing the vfork parent to resume execution.
1589 fork-events and vfork-events features in qSupported
1590 The qSupported packet allows GDB to request support for fork and
1591 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1592 and the qSupported response can contain the corresponding
1593 'stubfeatures'. Set and show commands can be used to display
1594 whether these features are enabled.
1596 * Extended-remote fork events
1598 ** GDB now has support for fork events on extended-remote Linux
1599 targets. For targets with Linux kernels 2.5.60 and later, this
1600 enables follow-fork-mode and detach-on-fork for both fork and
1601 vfork, as well as fork and vfork catchpoints.
1603 * The info record command now shows the recording format and the
1604 branch tracing configuration for the current thread when using
1605 the btrace record target.
1606 For the BTS format, it shows the ring buffer size.
1608 * GDB now has support for DTrace USDT (Userland Static Defined
1609 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1611 * GDB now supports access to vector registers on S/390 GNU/Linux
1614 * Removed command line options
1616 -xdb HP-UX XDB compatibility mode.
1618 * Removed targets and native configurations
1620 HP/PA running HP-UX hppa*-*-hpux*
1621 Itanium running HP-UX ia64-*-hpux*
1623 * New configure options
1626 This configure option allows the user to build GDB with support for
1627 Intel Processor Trace (default: auto). This requires libipt.
1629 --with-libipt-prefix=PATH
1630 Specify the path to the version of libipt that GDB should use.
1631 $PATH/include should contain the intel-pt.h header and
1632 $PATH/lib should contain the libipt.so library.
1634 *** Changes in GDB 7.9.1
1638 ** Xmethods can now specify a result type.
1640 *** Changes in GDB 7.9
1642 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1646 ** You can now access frame registers from Python scripts.
1647 ** New attribute 'producer' for gdb.Symtab objects.
1648 ** gdb.Objfile objects have a new attribute "progspace",
1649 which is the gdb.Progspace object of the containing program space.
1650 ** gdb.Objfile objects have a new attribute "owner".
1651 ** gdb.Objfile objects have a new attribute "build_id",
1652 which is the build ID generated when the file was built.
1653 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1654 ** A new event "gdb.clear_objfiles" has been added, triggered when
1655 selecting a new file to debug.
1656 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1657 ** New function gdb.lookup_objfile.
1659 New events which are triggered when GDB modifies the state of the
1662 ** gdb.events.inferior_call_pre: Function call is about to be made.
1663 ** gdb.events.inferior_call_post: Function call has just been made.
1664 ** gdb.events.memory_changed: A memory location has been altered.
1665 ** gdb.events.register_changed: A register has been altered.
1667 * New Python-based convenience functions:
1669 ** $_caller_is(name [, number_of_frames])
1670 ** $_caller_matches(regexp [, number_of_frames])
1671 ** $_any_caller_is(name [, number_of_frames])
1672 ** $_any_caller_matches(regexp [, number_of_frames])
1674 * GDB now supports the compilation and injection of source code into
1675 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1676 to compile the source code to object code, and if successful, inject
1677 and execute that code within the current context of the inferior.
1678 Currently the C language is supported. The commands used to
1679 interface with this new feature are:
1681 compile code [-raw|-r] [--] [source code]
1682 compile file [-raw|-r] filename
1686 demangle [-l language] [--] name
1687 Demangle "name" in the specified language, or the current language
1688 if elided. This command is renamed from the "maint demangle" command.
1689 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1690 as "maint demangler-warning".
1692 queue-signal signal-name-or-number
1693 Queue a signal to be delivered to the thread when it is resumed.
1695 add-auto-load-scripts-directory directory
1696 Add entries to the list of directories from which to load auto-loaded
1699 maint print user-registers
1700 List all currently available "user" registers.
1702 compile code [-r|-raw] [--] [source code]
1703 Compile, inject, and execute in the inferior the executable object
1704 code produced by compiling the provided source code.
1706 compile file [-r|-raw] filename
1707 Compile and inject into the inferior the executable object code
1708 produced by compiling the source code stored in the filename
1711 * On resume, GDB now always passes the signal the program had stopped
1712 for to the thread the signal was sent to, even if the user changed
1713 threads before resuming. Previously GDB would often (but not
1714 always) deliver the signal to the thread that happens to be current
1717 * Conversely, the "signal" command now consistently delivers the
1718 requested signal to the current thread. GDB now asks for
1719 confirmation if the program had stopped for a signal and the user
1720 switched threads meanwhile.
1722 * "breakpoint always-inserted" modes "off" and "auto" merged.
1724 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1725 won't remove breakpoints from the target until all threads stop,
1726 even in non-stop mode. The "auto" mode has been removed, and "off"
1727 is now the default mode.
1731 set debug symbol-lookup
1732 show debug symbol-lookup
1733 Control display of debugging info regarding symbol lookup.
1737 ** The -list-thread-groups command outputs an exit-code field for
1738 inferiors that have exited.
1742 MIPS SDE mips*-sde*-elf*
1746 Support for these obsolete configurations has been removed.
1748 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1749 SGI Irix-5.x mips-*-irix5*
1750 SGI Irix-6.x mips-*-irix6*
1751 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1752 VAX running Ultrix vax-*-ultrix*
1754 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1755 and "assf"), have been removed. Use the "sharedlibrary" command, or
1756 its alias "share", instead.
1758 *** Changes in GDB 7.8
1760 * New command line options
1763 This is an alias for the --data-directory option.
1765 * GDB supports printing and modifying of variable length automatic arrays
1766 as specified in ISO C99.
1768 * The ARM simulator now supports instruction level tracing
1769 with or without disassembly.
1773 GDB now has support for scripting using Guile. Whether this is
1774 available is determined at configure time.
1775 Guile version 2.0 or greater is required.
1776 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1778 * New commands (for set/show, see "New options" below)
1782 Invoke CODE by passing it to the Guile interpreter.
1786 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1788 info auto-load guile-scripts [regexp]
1789 Print the list of automatically loaded Guile scripts.
1791 * The source command is now capable of sourcing Guile scripts.
1792 This feature is dependent on the debugger being built with Guile support.
1796 set print symbol-loading (off|brief|full)
1797 show print symbol-loading
1798 Control whether to print informational messages when loading symbol
1799 information for a file. The default is "full", but when debugging
1800 programs with large numbers of shared libraries the amount of output
1801 becomes less useful.
1803 set guile print-stack (none|message|full)
1804 show guile print-stack
1805 Show a stack trace when an error is encountered in a Guile script.
1807 set auto-load guile-scripts (on|off)
1808 show auto-load guile-scripts
1809 Control auto-loading of Guile script files.
1811 maint ada set ignore-descriptive-types (on|off)
1812 maint ada show ignore-descriptive-types
1813 Control whether the debugger should ignore descriptive types in Ada
1814 programs. The default is not to ignore the descriptive types. See
1815 the user manual for more details on descriptive types and the intended
1816 usage of this option.
1818 set auto-connect-native-target
1820 Control whether GDB is allowed to automatically connect to the
1821 native target for the run, attach, etc. commands when not connected
1822 to any target yet. See also "target native" below.
1824 set record btrace replay-memory-access (read-only|read-write)
1825 show record btrace replay-memory-access
1826 Control what memory accesses are allowed during replay.
1828 maint set target-async (on|off)
1829 maint show target-async
1830 This controls whether GDB targets operate in synchronous or
1831 asynchronous mode. Normally the default is asynchronous, if it is
1832 available; but this can be changed to more easily debug problems
1833 occurring only in synchronous mode.
1835 set mi-async (on|off)
1837 Control whether MI asynchronous mode is preferred. This supersedes
1838 "set target-async" of previous GDB versions.
1840 * "set target-async" is deprecated as a CLI option and is now an alias
1841 for "set mi-async" (only puts MI into async mode).
1843 * Background execution commands (e.g., "c&", "s&", etc.) are now
1844 possible ``out of the box'' if the target supports them. Previously
1845 the user would need to explicitly enable the possibility with the
1846 "set target-async on" command.
1848 * New features in the GDB remote stub, GDBserver
1850 ** New option --debug-format=option1[,option2,...] allows one to add
1851 additional text to each output. At present only timestamps
1852 are supported: --debug-format=timestamps.
1853 Timestamps can also be turned on with the
1854 "monitor set debug-format timestamps" command from GDB.
1856 * The 'record instruction-history' command now starts counting instructions
1857 at one. This also affects the instruction ranges reported by the
1858 'record function-call-history' command when given the /i modifier.
1860 * The command 'record function-call-history' supports a new modifier '/c' to
1861 indent the function names based on their call stack depth.
1862 The fields for the '/i' and '/l' modifier have been reordered.
1863 The source line range is now prefixed with 'at'.
1864 The instruction range is now prefixed with 'inst'.
1865 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1866 "record instruction-history" and "list" commands.
1868 * The ranges given as arguments to the 'record function-call-history' and
1869 'record instruction-history' commands are now inclusive.
1871 * The btrace record target now supports the 'record goto' command.
1872 For locations inside the execution trace, the back trace is computed
1873 based on the information stored in the execution trace.
1875 * The btrace record target supports limited reverse execution and replay.
1876 The target does not record data and therefore does not allow reading
1877 memory or registers.
1879 * The "catch syscall" command now works on s390*-linux* targets.
1881 * The "compare-sections" command is no longer specific to target
1882 remote. It now works with all targets.
1884 * All native targets are now consistently called "native".
1885 Consequently, the "target child", "target GNU", "target djgpp",
1886 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1887 commands have been replaced with "target native". The QNX/NTO port
1888 leaves the "procfs" target in place and adds a "native" target for
1889 consistency with other ports. The impact on users should be minimal
1890 as these commands previously either throwed an error, or were
1891 no-ops. The target's name is visible in the output of the following
1892 commands: "help target", "info target", "info files", "maint print
1895 * The "target native" command now connects to the native target. This
1896 can be used to launch native programs even when "set
1897 auto-connect-native-target" is set to off.
1899 * GDB now supports access to Intel MPX registers on GNU/Linux.
1901 * Support for Intel AVX-512 registers on GNU/Linux.
1902 Support displaying and modifying Intel AVX-512 registers
1903 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1905 * New remote packets
1907 qXfer:btrace:read's annex
1908 The qXfer:btrace:read packet supports a new annex 'delta' to read
1909 branch trace incrementally.
1913 ** Valid Python operations on gdb.Value objects representing
1914 structs/classes invoke the corresponding overloaded operators if
1916 ** New `Xmethods' feature in the Python API. Xmethods are
1917 additional methods or replacements for existing methods of a C++
1918 class. This feature is useful for those cases where a method
1919 defined in C++ source code could be inlined or optimized out by
1920 the compiler, making it unavailable to GDB.
1923 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1925 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1926 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1927 its alias "share", instead.
1929 * The commands "set remotebaud" and "show remotebaud" are no longer
1930 supported. Use "set serial baud" and "show serial baud" (respectively)
1935 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1936 target-async". The latter is left as a deprecated alias of the
1937 former for backward compatibility. If the target supports it,
1938 CLI background execution commands are now always possible by
1939 default, independently of whether the frontend stated a
1940 preference for asynchronous execution with "-gdb-set mi-async".
1941 Previously "-gdb-set target-async off" affected both MI execution
1942 commands and CLI execution commands.
1944 *** Changes in GDB 7.7
1946 * Improved support for process record-replay and reverse debugging on
1947 arm*-linux* targets. Support for thumb32 and syscall instruction
1948 recording has been added.
1950 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1952 * GDB now supports Fission DWP file format version 2.
1953 http://gcc.gnu.org/wiki/DebugFission
1955 * New convenience function "$_isvoid", to check whether an expression
1956 is void. A void expression is an expression where the type of the
1957 result is "void". For example, some convenience variables may be
1958 "void" when evaluated (e.g., "$_exitcode" before the execution of
1959 the program being debugged; or an undefined convenience variable).
1960 Another example, when calling a function whose return type is
1963 * The "maintenance print objfiles" command now takes an optional regexp.
1965 * The "catch syscall" command now works on arm*-linux* targets.
1967 * GDB now consistently shows "<not saved>" when printing values of
1968 registers the debug info indicates have not been saved in the frame
1969 and there's nowhere to retrieve them from
1970 (callee-saved/call-clobbered registers):
1975 (gdb) info registers rax
1978 Before, the former would print "<optimized out>", and the latter
1979 "*value not available*".
1981 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1986 ** Frame filters and frame decorators have been added.
1987 ** Temporary breakpoints are now supported.
1988 ** Line tables representation has been added.
1989 ** New attribute 'parent_type' for gdb.Field objects.
1990 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1991 ** New attribute 'name' for gdb.Type objects.
1995 Nios II ELF nios2*-*-elf
1996 Nios II GNU/Linux nios2*-*-linux
1997 Texas Instruments MSP430 msp430*-*-elf
1999 * Removed native configurations
2001 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2002 been removed. ELF variants of these configurations are kept supported.
2004 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2005 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2006 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2007 i[34567]86-*-openbsd3.[0-3]
2008 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2009 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2010 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2014 Like "catch throw", but catches a re-thrown exception.
2015 maint check-psymtabs
2016 Renamed from old "maint check-symtabs".
2018 Perform consistency checks on symtabs.
2019 maint expand-symtabs
2020 Expand symtabs matching an optional regexp.
2023 Display the details of GDB configure-time options.
2025 maint set|show per-command
2026 maint set|show per-command space
2027 maint set|show per-command time
2028 maint set|show per-command symtab
2029 Enable display of per-command gdb resource usage.
2031 remove-symbol-file FILENAME
2032 remove-symbol-file -a ADDRESS
2033 Remove a symbol file added via add-symbol-file. The file to remove
2034 can be identified by its filename or by an address that lies within
2035 the boundaries of this symbol file in memory.
2038 info exceptions REGEXP
2039 Display the list of Ada exceptions defined in the program being
2040 debugged. If provided, only the exceptions whose names match REGEXP
2045 set debug symfile off|on
2047 Control display of debugging info regarding reading symbol files and
2048 symbol tables within those files
2050 set print raw frame-arguments
2051 show print raw frame-arguments
2052 Set/show whether to print frame arguments in raw mode,
2053 disregarding any defined pretty-printers.
2055 set remote trace-status-packet
2056 show remote trace-status-packet
2057 Set/show the use of remote protocol qTStatus packet.
2061 Control display of debugging messages related to Nios II targets.
2065 Control whether target-assisted range stepping is enabled.
2067 set startup-with-shell
2068 show startup-with-shell
2069 Specifies whether Unix child processes are started via a shell or
2074 Use the target memory cache for accesses to the code segment. This
2075 improves performance of remote debugging (particularly disassembly).
2077 * You can now use a literal value 'unlimited' for options that
2078 interpret 0 or -1 as meaning "unlimited". E.g., "set
2079 trace-buffer-size unlimited" is now an alias for "set
2080 trace-buffer-size -1" and "set height unlimited" is now an alias for
2083 * The "set debug symtab-create" debugging option of GDB has been changed to
2084 accept a verbosity level. 0 means "off", 1 provides basic debugging
2085 output, and values of 2 or greater provides more verbose output.
2087 * New command-line options
2089 Display the details of GDB configure-time options.
2091 * The command 'tsave' can now support new option '-ctf' to save trace
2092 buffer in Common Trace Format.
2094 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2097 * GDB now implements the the C++ 'typeid' operator.
2099 * The new convenience variable $_exception holds the exception being
2100 thrown or caught at an exception-related catchpoint.
2102 * The exception-related catchpoints, like "catch throw", now accept a
2103 regular expression which can be used to filter exceptions by type.
2105 * The new convenience variable $_exitsignal is automatically set to
2106 the terminating signal number when the program being debugged dies
2107 due to an uncaught signal.
2111 ** All MI commands now accept an optional "--language" option.
2112 Support for this feature can be verified by using the "-list-features"
2113 command, which should contain "language-option".
2115 ** The new command -info-gdb-mi-command allows the user to determine
2116 whether a GDB/MI command is supported or not.
2118 ** The "^error" result record returned when trying to execute an undefined
2119 GDB/MI command now provides a variable named "code" whose content is the
2120 "undefined-command" error code. Support for this feature can be verified
2121 by using the "-list-features" command, which should contain
2122 "undefined-command-error-code".
2124 ** The -trace-save MI command can optionally save trace buffer in Common
2127 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2129 ** The command -data-list-register-values now accepts an optional
2130 "--skip-unavailable" option. When used, only the available registers
2133 ** The new command -trace-frame-collected dumps collected variables,
2134 computed expressions, tvars, memory and registers in a traceframe.
2136 ** The commands -stack-list-locals, -stack-list-arguments and
2137 -stack-list-variables now accept an option "--skip-unavailable".
2138 When used, only the available locals or arguments are displayed.
2140 ** The -exec-run command now accepts an optional "--start" option.
2141 When used, the command follows the same semantics as the "start"
2142 command, stopping the program's execution at the start of its
2143 main subprogram. Support for this feature can be verified using
2144 the "-list-features" command, which should contain
2145 "exec-run-start-option".
2147 ** The new commands -catch-assert and -catch-exceptions insert
2148 catchpoints stopping the program when Ada exceptions are raised.
2150 ** The new command -info-ada-exceptions provides the equivalent of
2151 the new "info exceptions" command.
2153 * New system-wide configuration scripts
2154 A GDB installation now provides scripts suitable for use as system-wide
2155 configuration scripts for the following systems:
2159 * GDB now supports target-assigned range stepping with remote targets.
2160 This improves the performance of stepping source lines by reducing
2161 the number of control packets from/to GDB. See "New remote packets"
2164 * GDB now understands the element 'tvar' in the XML traceframe info.
2165 It has the id of the collected trace state variables.
2167 * On S/390 targets that provide the transactional-execution feature,
2168 the program interruption transaction diagnostic block (TDB) is now
2169 represented as a number of additional "registers" in GDB.
2171 * New remote packets
2175 The vCont packet supports a new 'r' action, that tells the remote
2176 stub to step through an address range itself, without GDB
2177 involvemement at each single-step.
2179 qXfer:libraries-svr4:read's annex
2180 The previously unused annex of the qXfer:libraries-svr4:read packet
2181 is now used to support passing an argument list. The remote stub
2182 reports support for this argument list to GDB's qSupported query.
2183 The defined arguments are "start" and "prev", used to reduce work
2184 necessary for library list updating, resulting in significant
2187 * New features in the GDB remote stub, GDBserver
2189 ** GDBserver now supports target-assisted range stepping. Currently
2190 enabled on x86/x86_64 GNU/Linux targets.
2192 ** GDBserver now adds element 'tvar' in the XML in the reply to
2193 'qXfer:traceframe-info:read'. It has the id of the collected
2194 trace state variables.
2196 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2199 * New 'z' formatter for printing and examining memory, this displays the
2200 value as hexadecimal zero padded on the left to the size of the type.
2202 * GDB can now use Windows x64 unwinding data.
2204 * The "set remotebaud" command has been replaced by "set serial baud".
2205 Similarly, "show remotebaud" has been replaced by "show serial baud".
2206 The "set remotebaud" and "show remotebaud" commands are still available
2207 to provide backward compatibility with older versions of GDB.
2209 *** Changes in GDB 7.6
2211 * Target record has been renamed to record-full.
2212 Record/replay is now enabled with the "record full" command.
2213 This also affects settings that are associated with full record/replay
2214 that have been moved from "set/show record" to "set/show record full":
2216 set|show record full insn-number-max
2217 set|show record full stop-at-limit
2218 set|show record full memory-query
2220 * A new record target "record-btrace" has been added. The new target
2221 uses hardware support to record the control-flow of a process. It
2222 does not support replaying the execution, but it implements the
2223 below new commands for investigating the recorded execution log.
2224 This new recording method can be enabled using:
2228 The "record-btrace" target is only available on Intel Atom processors
2229 and requires a Linux kernel 2.6.32 or later.
2231 * Two new commands have been added for record/replay to give information
2232 about the recorded execution without having to replay the execution.
2233 The commands are only supported by "record btrace".
2235 record instruction-history prints the execution history at
2236 instruction granularity
2238 record function-call-history prints the execution history at
2239 function granularity
2241 * New native configurations
2243 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2244 FreeBSD/powerpc powerpc*-*-freebsd
2245 x86_64/Cygwin x86_64-*-cygwin*
2246 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2250 ARM AArch64 aarch64*-*-elf
2251 ARM AArch64 GNU/Linux aarch64*-*-linux
2252 Lynx 178 PowerPC powerpc-*-lynx*178
2253 x86_64/Cygwin x86_64-*-cygwin*
2254 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2256 * If the configured location of system.gdbinit file (as given by the
2257 --with-system-gdbinit option at configure time) is in the
2258 data-directory (as specified by --with-gdb-datadir at configure
2259 time) or in one of its subdirectories, then GDB will look for the
2260 system-wide init file in the directory specified by the
2261 --data-directory command-line option.
2263 * New command line options:
2265 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2266 other initialization files, unlike -nx which disables all of them.
2268 * Removed command line options
2270 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2273 * The 'ptype' and 'whatis' commands now accept an argument to control
2276 * 'info proc' now works on some core files.
2280 ** Vectors can be created with gdb.Type.vector.
2282 ** Python's atexit.register now works in GDB.
2284 ** Types can be pretty-printed via a Python API.
2286 ** Python 3 is now supported (in addition to Python 2.4 or later)
2288 ** New class gdb.Architecture exposes GDB's internal representation
2289 of architecture in the Python API.
2291 ** New method Frame.architecture returns the gdb.Architecture object
2292 corresponding to the frame's architecture.
2294 * New Python-based convenience functions:
2296 ** $_memeq(buf1, buf2, length)
2297 ** $_streq(str1, str2)
2299 ** $_regex(str, regex)
2301 * The 'cd' command now defaults to using '~' (the home directory) if not
2304 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2305 default for GCC since November 2000.
2307 * The command 'forward-search' can now be abbreviated as 'fo'.
2309 * The command 'info tracepoints' can now display 'installed on target'
2310 or 'not installed on target' for each non-pending location of tracepoint.
2312 * New configure options
2314 --enable-libmcheck/--disable-libmcheck
2315 By default, development versions are built with -lmcheck on hosts
2316 that support it, in order to help track memory corruption issues.
2317 Release versions, on the other hand, are built without -lmcheck
2318 by default. The --enable-libmcheck/--disable-libmcheck configure
2319 options allow the user to override that default.
2320 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2321 This configure option allows the user to build GDB with
2322 libbabeltrace using which GDB can read Common Trace Format data.
2324 * New commands (for set/show, see "New options" below)
2327 Catch signals. This is similar to "handle", but allows commands and
2328 conditions to be attached.
2331 List the BFDs known to GDB.
2333 python-interactive [command]
2335 Start a Python interactive prompt, or evaluate the optional command
2336 and print the result of expressions.
2339 "py" is a new alias for "python".
2341 enable type-printer [name]...
2342 disable type-printer [name]...
2343 Enable or disable type printers.
2347 ** For the Renesas Super-H architecture, the "regs" command has been removed
2348 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2353 set print type methods (on|off)
2354 show print type methods
2355 Control whether method declarations are displayed by "ptype".
2356 The default is to show them.
2358 set print type typedefs (on|off)
2359 show print type typedefs
2360 Control whether typedef definitions are displayed by "ptype".
2361 The default is to show them.
2363 set filename-display basename|relative|absolute
2364 show filename-display
2365 Control the way in which filenames is displayed.
2366 The default is "relative", which preserves previous behavior.
2368 set trace-buffer-size
2369 show trace-buffer-size
2370 Request target to change the size of trace buffer.
2372 set remote trace-buffer-size-packet auto|on|off
2373 show remote trace-buffer-size-packet
2374 Control the use of the remote protocol `QTBuffer:size' packet.
2378 Control display of debugging messages related to ARM AArch64.
2381 set debug coff-pe-read
2382 show debug coff-pe-read
2383 Control display of debugging messages related to reading of COFF/PE
2388 Control display of debugging messages related to Mach-O symbols
2391 set debug notification
2392 show debug notification
2393 Control display of debugging info for async remote notification.
2397 ** Command parameter changes are now notified using new async record
2398 "=cmd-param-changed".
2399 ** Trace frame changes caused by command "tfind" are now notified using
2400 new async record "=traceframe-changed".
2401 ** The creation, deletion and modification of trace state variables
2402 are now notified using new async records "=tsv-created",
2403 "=tsv-deleted" and "=tsv-modified".
2404 ** The start and stop of process record are now notified using new
2405 async record "=record-started" and "=record-stopped".
2406 ** Memory changes are now notified using new async record
2408 ** The data-disassemble command response will include a "fullname" field
2409 containing the absolute file name when source has been requested.
2410 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2411 command, to allow pattern filling of memory areas.
2412 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2413 library load/unload events.
2414 ** The response to breakpoint commands and breakpoint async records
2415 includes an "installed" field containing a boolean state about each
2416 non-pending tracepoint location is whether installed on target or not.
2417 ** Output of the "-trace-status" command includes a "trace-file" field
2418 containing the name of the trace file being examined. This field is
2419 optional, and only present when examining a trace file.
2420 ** The "fullname" field is now always present along with the "file" field,
2421 even if the file cannot be found by GDB.
2423 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2424 You must have the LZMA library available when configuring GDB for this
2425 feature to be enabled. For more information, see:
2426 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2428 * New remote packets
2431 Set the size of trace buffer. The remote stub reports support for this
2432 packet to gdb's qSupported query.
2435 Enable Branch Trace Store (BTS)-based branch tracing for the current
2436 thread. The remote stub reports support for this packet to gdb's
2440 Disable branch tracing for the current thread. The remote stub reports
2441 support for this packet to gdb's qSupported query.
2444 Read the traced branches for the current thread. The remote stub
2445 reports support for this packet to gdb's qSupported query.
2447 *** Changes in GDB 7.5
2449 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2450 for more x32 ABI info.
2452 * GDB now supports access to MIPS DSP registers on Linux targets.
2454 * GDB now supports debugging microMIPS binaries.
2456 * The "info os" command on GNU/Linux can now display information on
2457 several new classes of objects managed by the operating system:
2458 "info os procgroups" lists process groups
2459 "info os files" lists file descriptors
2460 "info os sockets" lists internet-domain sockets
2461 "info os shm" lists shared-memory regions
2462 "info os semaphores" lists semaphores
2463 "info os msg" lists message queues
2464 "info os modules" lists loaded kernel modules
2466 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2467 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2468 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2469 options and inspect the probe arguments using the new $_probe_arg family
2470 of convenience variables. You can obtain more information about SystemTap
2471 in <http://sourceware.org/systemtap/>.
2473 * GDB now supports reversible debugging on ARM, it allows you to
2474 debug basic ARM and THUMB instructions, and provides
2475 record/replay support.
2477 * The option "symbol-reloading" has been deleted as it is no longer used.
2481 ** GDB commands implemented in Python can now be put in command class
2484 ** The "maint set python print-stack on|off" is now deleted.
2486 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2487 apply "flag enum"-style pretty-printing to any enum.
2489 ** gdb.lookup_symbol can now work when there is no current frame.
2491 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2492 the source at which the symbol was defined.
2494 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2495 method 'value'. The former indicates whether the symbol needs a
2496 frame in order to compute its value, and the latter computes the
2499 ** A new method 'referenced_value' on gdb.Value objects which can
2500 dereference pointer as well as C++ reference values.
2502 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2503 which return the global and static blocks (as gdb.Block objects),
2504 of the underlying symbol table, respectively.
2506 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2507 object associated with a PC value.
2509 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2510 of the address range occupied by code for the current source line.
2512 * Go language support.
2513 GDB now supports debugging programs written in the Go programming
2516 * GDBserver now supports stdio connections.
2517 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2519 * The binary "gdbtui" can no longer be built or installed.
2520 Use "gdb -tui" instead.
2522 * GDB will now print "flag" enums specially. A flag enum is one where
2523 all the enumerator values have no bits in common when pairwise
2524 "and"ed. When printing a value whose type is a flag enum, GDB will
2525 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2526 (gdb) print (enum E) 3
2529 * The filename part of a linespec will now match trailing components
2530 of a source file name. For example, "break gcc/expr.c:1000" will
2531 now set a breakpoint in build/gcc/expr.c, but not
2532 build/libcpp/expr.c.
2534 * The "info proc" and "generate-core-file" commands will now also
2535 work on remote targets connected to GDBserver on Linux.
2537 * The command "info catch" has been removed. It has been disabled
2538 since December 2007.
2540 * The "catch exception" and "catch assert" commands now accept
2541 a condition at the end of the command, much like the "break"
2542 command does. For instance:
2544 (gdb) catch exception Constraint_Error if Barrier = True
2546 Previously, it was possible to add a condition to such catchpoints,
2547 but it had to be done as a second step, after the catchpoint had been
2548 created, using the "condition" command.
2550 * The "info static-tracepoint-marker" command will now also work on
2551 native Linux targets with in-process agent.
2553 * GDB can now set breakpoints on inlined functions.
2555 * The .gdb_index section has been updated to include symbols for
2556 inlined functions. GDB will ignore older .gdb_index sections by
2557 default, which could cause symbol files to be loaded more slowly
2558 until their .gdb_index sections can be recreated. The new command
2559 "set use-deprecated-index-sections on" will cause GDB to use any older
2560 .gdb_index sections it finds. This will restore performance, but the
2561 ability to set breakpoints on inlined functions will be lost in symbol
2562 files with older .gdb_index sections.
2564 The .gdb_index section has also been updated to record more information
2565 about each symbol. This speeds up the "info variables", "info functions"
2566 and "info types" commands when used with programs having the .gdb_index
2567 section, as well as speeding up debugging with shared libraries using
2568 the .gdb_index section.
2570 * Ada support for GDB/MI Variable Objects has been added.
2572 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2577 ** New command -info-os is the MI equivalent of "info os".
2579 ** Output logs ("set logging" and related) now include MI output.
2583 ** "set use-deprecated-index-sections on|off"
2584 "show use-deprecated-index-sections on|off"
2585 Controls the use of deprecated .gdb_index sections.
2587 ** "catch load" and "catch unload" can be used to stop when a shared
2588 library is loaded or unloaded, respectively.
2590 ** "enable count" can be used to auto-disable a breakpoint after
2593 ** "info vtbl" can be used to show the virtual method tables for
2594 C++ and Java objects.
2596 ** "explore" and its sub commands "explore value" and "explore type"
2597 can be used to recursively explore values and types of
2598 expressions. These commands are available only if GDB is
2599 configured with '--with-python'.
2601 ** "info auto-load" shows status of all kinds of auto-loaded files,
2602 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2603 sequences of commands files, "info auto-load python-scripts"
2604 shows status of auto-loading Python script files,
2605 "info auto-load local-gdbinit" shows status of loading init file
2606 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2607 status of inferior specific thread debugging shared library loading.
2609 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2610 and "show auto-load-scripts" commands have been deprecated, use their
2611 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2612 and "show auto-load python-scripts" counterparts instead.
2614 ** "dprintf location,format,args..." creates a dynamic printf, which
2615 is basically a breakpoint that does a printf and immediately
2616 resumes your program's execution, so it is like a printf that you
2617 can insert dynamically at runtime instead of at compiletime.
2619 ** "set print symbol"
2621 Controls whether GDB attempts to display the symbol, if any,
2622 corresponding to addresses it prints. This defaults to "on", but
2623 you can set it to "off" to restore GDB's previous behavior.
2625 * Deprecated commands
2627 ** For the Renesas Super-H architecture, the "regs" command has been
2628 deprecated, and "info all-registers" should be used instead.
2632 Renesas RL78 rl78-*-elf
2633 HP OpenVMS ia64 ia64-hp-openvms*
2635 * GDBserver supports evaluation of breakpoint conditions. When
2636 support is advertised by GDBserver, GDB may be told to send the
2637 breakpoint conditions in bytecode form to GDBserver. GDBserver
2638 will only report the breakpoint trigger to GDB when its condition
2643 set mips compression
2644 show mips compression
2645 Select the compressed ISA encoding used in functions that have no symbol
2646 information available. The encoding can be set to either of:
2649 and is updated automatically from ELF file flags if available.
2651 set breakpoint condition-evaluation
2652 show breakpoint condition-evaluation
2653 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2654 GDBserver ("target"). Default option "auto" chooses the most efficient
2656 This option can improve debugger efficiency depending on the speed of the
2660 Disable auto-loading globally.
2663 Show auto-loading setting of all kinds of auto-loaded files.
2665 set auto-load gdb-scripts on|off
2666 show auto-load gdb-scripts
2667 Control auto-loading of GDB canned sequences of commands files.
2669 set auto-load python-scripts on|off
2670 show auto-load python-scripts
2671 Control auto-loading of Python script files.
2673 set auto-load local-gdbinit on|off
2674 show auto-load local-gdbinit
2675 Control loading of init file (.gdbinit) from current directory.
2677 set auto-load libthread-db on|off
2678 show auto-load libthread-db
2679 Control auto-loading of inferior specific thread debugging shared library.
2681 set auto-load scripts-directory <dir1>[:<dir2>...]
2682 show auto-load scripts-directory
2683 Set a list of directories from which to load auto-loaded scripts.
2684 Automatically loaded Python scripts and GDB scripts are located in one
2685 of the directories listed by this option.
2686 The delimiter (':' above) may differ according to the host platform.
2688 set auto-load safe-path <dir1>[:<dir2>...]
2689 show auto-load safe-path
2690 Set a list of directories from which it is safe to auto-load files.
2691 The delimiter (':' above) may differ according to the host platform.
2693 set debug auto-load on|off
2694 show debug auto-load
2695 Control display of debugging info for auto-loading the files above.
2697 set dprintf-style gdb|call|agent
2699 Control the way in which a dynamic printf is performed; "gdb"
2700 requests a GDB printf command, while "call" causes dprintf to call a
2701 function in the inferior. "agent" requests that the target agent
2702 (such as GDBserver) do the printing.
2704 set dprintf-function <expr>
2705 show dprintf-function
2706 set dprintf-channel <expr>
2707 show dprintf-channel
2708 Set the function and optional first argument to the call when using
2709 the "call" style of dynamic printf.
2711 set disconnected-dprintf on|off
2712 show disconnected-dprintf
2713 Control whether agent-style dynamic printfs continue to be in effect
2714 after GDB disconnects.
2716 * New configure options
2718 --with-auto-load-dir
2719 Configure default value for the 'set auto-load scripts-directory'
2720 setting above. It defaults to '$debugdir:$datadir/auto-load',
2721 $debugdir representing global debugging info directories (available
2722 via 'show debug-file-directory') and $datadir representing GDB's data
2723 directory (available via 'show data-directory').
2725 --with-auto-load-safe-path
2726 Configure default value for the 'set auto-load safe-path' setting
2727 above. It defaults to the --with-auto-load-dir setting.
2729 --without-auto-load-safe-path
2730 Set 'set auto-load safe-path' to '/', effectively disabling this
2733 * New remote packets
2735 z0/z1 conditional breakpoints extension
2737 The z0/z1 breakpoint insertion packets have been extended to carry
2738 a list of conditional expressions over to the remote stub depending on the
2739 condition evaluation mode. The use of this extension can be controlled
2740 via the "set remote conditional-breakpoints-packet" command.
2744 Specify the signals which the remote stub may pass to the debugged
2745 program without GDB involvement.
2747 * New command line options
2749 --init-command=FILE, -ix Like --command, -x but execute it
2750 before loading inferior.
2751 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2752 execute it before loading inferior.
2754 *** Changes in GDB 7.4
2756 * GDB now handles ambiguous linespecs more consistently; the existing
2757 FILE:LINE support has been expanded to other types of linespecs. A
2758 breakpoint will now be set on all matching locations in all
2759 inferiors, and locations will be added or removed according to
2762 * GDB now allows you to skip uninteresting functions and files when
2763 stepping with the "skip function" and "skip file" commands.
2765 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2766 and "show remote hardware-watchpoint-length-limit". These allows to
2767 set or show the maximum length limit (in bytes) of a remote
2768 target hardware watchpoint.
2770 This allows e.g. to use "unlimited" hardware watchpoints with the
2771 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2772 watchpoints are slower than real hardware watchpoints but are
2773 significantly faster than gdb software watchpoints.
2777 ** The register_pretty_printer function in module gdb.printing now takes
2778 an optional `replace' argument. If True, the new printer replaces any
2781 ** The "maint set python print-stack on|off" command has been
2782 deprecated and will be deleted in GDB 7.5.
2783 A new command: "set python print-stack none|full|message" has
2784 replaced it. Additionally, the default for "print-stack" is
2785 now "message", which just prints the error message without
2788 ** A prompt substitution hook (prompt_hook) is now available to the
2791 ** A new Python module, gdb.prompt has been added to the GDB Python
2792 modules library. This module provides functionality for
2793 escape sequences in prompts (used by set/show
2794 extended-prompt). These escape sequences are replaced by their
2795 corresponding value.
2797 ** Python commands and convenience-functions located in
2798 'data-directory'/python/gdb/command and
2799 'data-directory'/python/gdb/function are now automatically loaded
2802 ** Blocks now provide four new attributes. global_block and
2803 static_block will return the global and static blocks
2804 respectively. is_static and is_global are boolean attributes
2805 that indicate if the block is one of those two types.
2807 ** Symbols now provide the "type" attribute, the type of the symbol.
2809 ** The "gdb.breakpoint" function has been deprecated in favor of
2812 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2813 of a function. This class is based on the "finish" command
2814 available in the CLI.
2816 ** Type objects for struct and union types now allow access to
2817 the fields using standard Python dictionary (mapping) methods.
2818 For example, "some_type['myfield']" now works, as does
2819 "some_type.items()".
2821 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2824 ** A new function, "deep_items" has been added to the gdb.types
2825 module in the GDB Python modules library. This function returns
2826 an iterator over the fields of a struct or union type. Unlike
2827 the standard Python "iteritems" method, it will recursively traverse
2828 any anonymous fields.
2832 ** "*stopped" events can report several new "reason"s, such as
2835 ** Breakpoint changes are now notified using new async records, like
2836 "=breakpoint-modified".
2838 ** New command -ada-task-info.
2840 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2841 $sdir specifies the default system locations of shared libraries.
2842 $pdir specifies the directory where the libpthread used by the application
2845 GDB no longer looks in $sdir and $pdir after it has searched the directories
2846 mentioned in libthread-db-search-path. If you want to search those
2847 directories, they must be specified in libthread-db-search-path.
2848 The default value of libthread-db-search-path on GNU/Linux and Solaris
2849 systems is now "$sdir:$pdir".
2851 $pdir is not supported by gdbserver, it is currently ignored.
2852 $sdir is supported by gdbserver.
2854 * New configure option --with-iconv-bin.
2855 When using the internationalization support like the one in the GNU C
2856 library, GDB will invoke the "iconv" program to get a list of supported
2857 character sets. If this program lives in a non-standard location, one can
2858 use this option to specify where to find it.
2860 * When natively debugging programs on PowerPC BookE processors running
2861 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2862 watchpoints, which specify a mask in addition to an address to watch.
2863 The mask specifies that some bits of an address (the bits which are
2864 reset in the mask) should be ignored when matching the address accessed
2865 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2866 section in the user manual for more details.
2868 * The new option --once causes GDBserver to stop listening for connections once
2869 the first connection is made. The listening port used by GDBserver will
2870 become available after that.
2872 * New commands "info macros" and "alias" have been added.
2874 * New function parameters suffix @entry specifies value of function parameter
2875 at the time the function got called. Entry values are available only since
2881 "!" is now an alias of the "shell" command.
2882 Note that no space is needed between "!" and SHELL COMMAND.
2886 watch EXPRESSION mask MASK_VALUE
2887 The watch command now supports the mask argument which allows creation
2888 of masked watchpoints, if the current architecture supports this feature.
2890 info auto-load-scripts [REGEXP]
2891 This command was formerly named "maintenance print section-scripts".
2892 It is now generally useful and is no longer a maintenance-only command.
2894 info macro [-all] [--] MACRO
2895 The info macro command has new options `-all' and `--'. The first for
2896 printing all definitions of a macro. The second for explicitly specifying
2897 the end of arguments and the beginning of the macro name in case the macro
2898 name starts with a hyphen.
2900 collect[/s] EXPRESSIONS
2901 The tracepoint collect command now takes an optional modifier "/s"
2902 that directs it to dereference pointer-to-character types and
2903 collect the bytes of memory up to a zero byte. The behavior is
2904 similar to what you see when you use the regular print command on a
2905 string. An optional integer following the "/s" sets a bound on the
2906 number of bytes that will be collected.
2909 The trace start command now interprets any supplied arguments as a
2910 note to be recorded with the trace run, with an effect similar to
2911 setting the variable trace-notes.
2914 The trace stop command now interprets any arguments as a note to be
2915 mentioned along with the tstatus report that the trace was stopped
2916 with a command. The effect is similar to setting the variable
2919 * Tracepoints can now be enabled and disabled at any time after a trace
2920 experiment has been started using the standard "enable" and "disable"
2921 commands. It is now possible to start a trace experiment with no enabled
2922 tracepoints; GDB will display a warning, but will allow the experiment to
2923 begin, assuming that tracepoints will be enabled as needed while the trace
2926 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2927 locations with 4-byte instructions, when they were previously
2928 limited to locations with instructions of 5 bytes or longer.
2932 set debug dwarf2-read
2933 show debug dwarf2-read
2934 Turns on or off display of debugging messages related to reading
2935 DWARF debug info. The default is off.
2937 set debug symtab-create
2938 show debug symtab-create
2939 Turns on or off display of debugging messages related to symbol table
2940 creation. The default is off.
2943 show extended-prompt
2944 Set the GDB prompt, and allow escape sequences to be inserted to
2945 display miscellaneous information (see 'help set extended-prompt'
2946 for the list of sequences). This prompt (and any information
2947 accessed through the escape sequences) is updated every time the
2948 prompt is displayed.
2950 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2951 show print entry-values
2952 Set printing of frame argument values at function entry. In some cases
2953 GDB can determine the value of function argument which was passed by the
2954 function caller, even if the value was modified inside the called function.
2956 set debug entry-values
2957 show debug entry-values
2958 Control display of debugging info for determining frame argument values at
2959 function entry and virtual tail call frames.
2961 set basenames-may-differ
2962 show basenames-may-differ
2963 Set whether a source file may have multiple base names.
2964 (A "base name" is the name of a file with the directory part removed.
2965 Example: The base name of "/home/user/hello.c" is "hello.c".)
2966 If set, GDB will canonicalize file names (e.g., expand symlinks)
2967 before comparing them. Canonicalization is an expensive operation,
2968 but it allows the same file be known by more than one base name.
2969 If not set (the default), all source files are assumed to have just
2970 one base name, and gdb will do file name comparisons more efficiently.
2976 Set a user name and notes for the current and any future trace runs.
2977 This is useful for long-running and/or disconnected traces, to
2978 inform others (or yourself) as to who is running the trace, supply
2979 contact information, or otherwise explain what is going on.
2981 set trace-stop-notes
2982 show trace-stop-notes
2983 Set a note attached to the trace run, that is displayed when the
2984 trace has been stopped by a tstop command. This is useful for
2985 instance as an explanation, if you are stopping a trace run that was
2986 started by someone else.
2988 * New remote packets
2992 Dynamically enable a tracepoint in a started trace experiment.
2996 Dynamically disable a tracepoint in a started trace experiment.
3000 Set the user and notes of the trace run.
3004 Query the current status of a tracepoint.
3008 Query the minimum length of instruction at which a fast tracepoint may
3011 * Dcache size (number of lines) and line-size are now runtime-configurable
3012 via "set dcache line" and "set dcache line-size" commands.
3016 Texas Instruments TMS320C6x tic6x-*-*
3020 Renesas RL78 rl78-*-elf
3022 *** Changes in GDB 7.3.1
3024 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3026 *** Changes in GDB 7.3
3028 * GDB has a new command: "thread find [REGEXP]".
3029 It finds the thread id whose name, target id, or thread extra info
3030 matches the given regular expression.
3032 * The "catch syscall" command now works on mips*-linux* targets.
3034 * The -data-disassemble MI command now supports modes 2 and 3 for
3035 dumping the instruction opcodes.
3037 * New command line options
3039 -data-directory DIR Specify DIR as the "data-directory".
3040 This is mostly for testing purposes.
3042 * The "maint set python auto-load on|off" command has been renamed to
3043 "set auto-load-scripts on|off".
3045 * GDB has a new command: "set directories".
3046 It is like the "dir" command except that it replaces the
3047 source path list instead of augmenting it.
3049 * GDB now understands thread names.
3051 On GNU/Linux, "info threads" will display the thread name as set by
3052 prctl or pthread_setname_np.
3054 There is also a new command, "thread name", which can be used to
3055 assign a name internally for GDB to display.
3058 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3059 has been integrated into GDB.
3063 ** The function gdb.Write now accepts an optional keyword 'stream'.
3064 This keyword, when provided, will direct the output to either
3065 stdout, stderr, or GDB's logging output.
3067 ** Parameters can now be be sub-classed in Python, and in particular
3068 you may implement the get_set_doc and get_show_doc functions.
3069 This improves how Parameter set/show documentation is processed
3070 and allows for more dynamic content.
3072 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3073 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3074 have an is_valid method.
3076 ** Breakpoints can now be sub-classed in Python, and in particular
3077 you may implement a 'stop' function that is executed each time
3078 the inferior reaches that breakpoint.
3080 ** New function gdb.lookup_global_symbol looks up a global symbol.
3082 ** GDB values in Python are now callable if the value represents a
3083 function. For example, if 'some_value' represents a function that
3084 takes two integer parameters and returns a value, you can call
3085 that function like so:
3087 result = some_value (10,20)
3089 ** Module gdb.types has been added.
3090 It contains a collection of utilities for working with gdb.Types objects:
3091 get_basic_type, has_field, make_enum_dict.
3093 ** Module gdb.printing has been added.
3094 It contains utilities for writing and registering pretty-printers.
3095 New classes: PrettyPrinter, SubPrettyPrinter,
3096 RegexpCollectionPrettyPrinter.
3097 New function: register_pretty_printer.
3099 ** New commands "info pretty-printers", "enable pretty-printer" and
3100 "disable pretty-printer" have been added.
3102 ** gdb.parameter("directories") is now available.
3104 ** New function gdb.newest_frame returns the newest frame in the
3107 ** The gdb.InferiorThread class has a new "name" attribute. This
3108 holds the thread's name.
3110 ** Python Support for Inferior events.
3111 Python scripts can add observers to be notified of events
3112 occurring in the process being debugged.
3113 The following events are currently supported:
3114 - gdb.events.cont Continue event.
3115 - gdb.events.exited Inferior exited event.
3116 - gdb.events.stop Signal received, and Breakpoint hit events.
3120 ** GDB now puts template parameters in scope when debugging in an
3121 instantiation. For example, if you have:
3123 template<int X> int func (void) { return X; }
3125 then if you step into func<5>, "print X" will show "5". This
3126 feature requires proper debuginfo support from the compiler; it
3127 was added to GCC 4.5.
3129 ** The motion commands "next", "finish", "until", and "advance" now
3130 work better when exceptions are thrown. In particular, GDB will
3131 no longer lose control of the inferior; instead, the GDB will
3132 stop the inferior at the point at which the exception is caught.
3133 This functionality requires a change in the exception handling
3134 code that was introduced in GCC 4.5.
3136 * GDB now follows GCC's rules on accessing volatile objects when
3137 reading or writing target state during expression evaluation.
3138 One notable difference to prior behavior is that "print x = 0"
3139 no longer generates a read of x; the value of the assignment is
3140 now always taken directly from the value being assigned.
3142 * GDB now has some support for using labels in the program's source in
3143 linespecs. For instance, you can use "advance label" to continue
3144 execution to a label.
3146 * GDB now has support for reading and writing a new .gdb_index
3147 section. This section holds a fast index of DWARF debugging
3148 information and can be used to greatly speed up GDB startup and
3149 operation. See the documentation for `save gdb-index' for details.
3151 * The "watch" command now accepts an optional "-location" argument.
3152 When used, this causes GDB to watch the memory referred to by the
3153 expression. Such a watchpoint is never deleted due to it going out
3156 * GDB now supports thread debugging of core dumps on GNU/Linux.
3158 GDB now activates thread debugging using the libthread_db library
3159 when debugging GNU/Linux core dumps, similarly to when debugging
3160 live processes. As a result, when debugging a core dump file, GDB
3161 is now able to display pthread_t ids of threads. For example, "info
3162 threads" shows the same output as when debugging the process when it
3163 was live. In earlier releases, you'd see something like this:
3166 * 1 LWP 6780 main () at main.c:10
3168 While now you see this:
3171 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3173 It is also now possible to inspect TLS variables when debugging core
3176 When debugging a core dump generated on a machine other than the one
3177 used to run GDB, you may need to point GDB at the correct
3178 libthread_db library with the "set libthread-db-search-path"
3179 command. See the user manual for more details on this command.
3181 * When natively debugging programs on PowerPC BookE processors running
3182 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3183 which stop execution of the inferior whenever it executes an instruction
3184 at any address within the specified range. See the "PowerPC Embedded"
3185 section in the user manual for more details.
3187 * New features in the GDB remote stub, GDBserver
3189 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3190 and i686 LynxOS (version 5.x).
3192 ** GDBserver is now supported on Blackfin Linux.
3194 * New native configurations
3196 ia64 HP-UX ia64-*-hpux*
3200 Analog Devices, Inc. Blackfin Processor bfin-*
3202 * Ada task switching is now supported on sparc-elf targets when
3203 debugging a program using the Ravenscar Profile. For more information,
3204 see the "Tasking Support when using the Ravenscar Profile" section
3205 in the GDB user manual.
3207 * Guile support was removed.
3209 * New features in the GNU simulator
3211 ** The --map-info flag lists all known core mappings.
3213 ** CFI flashes may be simulated via the "cfi" device.
3215 *** Changes in GDB 7.2
3217 * Shared library support for remote targets by default
3219 When GDB is configured for a generic, non-OS specific target, like
3220 for example, --target=arm-eabi or one of the many *-*-elf targets,
3221 GDB now queries remote stubs for loaded shared libraries using the
3222 `qXfer:libraries:read' packet. Previously, shared library support
3223 was always disabled for such configurations.
3227 ** Argument Dependent Lookup (ADL)
3229 In C++ ADL lookup directs function search to the namespaces of its
3230 arguments even if the namespace has not been imported.
3240 Here the compiler will search for `foo' in the namespace of 'b'
3241 and find A::foo. GDB now supports this. This construct is commonly
3242 used in the Standard Template Library for operators.
3244 ** Improved User Defined Operator Support
3246 In addition to member operators, GDB now supports lookup of operators
3247 defined in a namespace and imported with a `using' directive, operators
3248 defined in the global scope, operators imported implicitly from an
3249 anonymous namespace, and the ADL operators mentioned in the previous
3251 GDB now also supports proper overload resolution for all the previously
3252 mentioned flavors of operators.
3254 ** static const class members
3256 Printing of static const class members that are initialized in the
3257 class definition has been fixed.
3259 * Windows Thread Information Block access.
3261 On Windows targets, GDB now supports displaying the Windows Thread
3262 Information Block (TIB) structure. This structure is visible either
3263 by using the new command `info w32 thread-information-block' or, by
3264 dereferencing the new convenience variable named `$_tlb', a
3265 thread-specific pointer to the TIB. This feature is also supported
3266 when remote debugging using GDBserver.
3268 * Static tracepoints
3270 Static tracepoints are calls in the user program into a tracing
3271 library. One such library is a port of the LTTng kernel tracer to
3272 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3273 When debugging with GDBserver, GDB now supports combining the GDB
3274 tracepoint machinery with such libraries. For example: the user can
3275 use GDB to probe a static tracepoint marker (a call from the user
3276 program into the tracing library) with the new "strace" command (see
3277 "New commands" below). This creates a "static tracepoint" in the
3278 breakpoint list, that can be manipulated with the same feature set
3279 as fast and regular tracepoints. E.g., collect registers, local and
3280 global variables, collect trace state variables, and define
3281 tracepoint conditions. In addition, the user can collect extra
3282 static tracepoint marker specific data, by collecting the new
3283 $_sdata internal variable. When analyzing the trace buffer, you can
3284 inspect $_sdata like any other variable available to GDB. For more
3285 information, see the "Tracepoints" chapter in GDB user manual. New
3286 remote packets have been defined to support static tracepoints, see
3287 the "New remote packets" section below.
3289 * Better reconstruction of tracepoints after disconnected tracing
3291 GDB will attempt to download the original source form of tracepoint
3292 definitions when starting a trace run, and then will upload these
3293 upon reconnection to the target, resulting in a more accurate
3294 reconstruction of the tracepoints that are in use on the target.
3298 You can now exercise direct control over the ways that GDB can
3299 affect your program. For instance, you can disallow the setting of
3300 breakpoints, so that the program can run continuously (assuming
3301 non-stop mode). In addition, the "observer" variable is available
3302 to switch all of the different controls; in observer mode, GDB
3303 cannot affect the target's behavior at all, which is useful for
3304 tasks like diagnosing live systems in the field.
3306 * The new convenience variable $_thread holds the number of the
3309 * New remote packets
3313 Return the address of the Windows Thread Information Block of a given thread.
3317 In response to several of the tracepoint packets, the target may now
3318 also respond with a number of intermediate `qRelocInsn' request
3319 packets before the final result packet, to have GDB handle
3320 relocating an instruction to execute at a different address. This
3321 is particularly useful for stubs that support fast tracepoints. GDB
3322 reports support for this feature in the qSupported packet.
3326 List static tracepoint markers in the target program.
3330 List static tracepoint markers at a given address in the target
3333 qXfer:statictrace:read
3335 Read the static trace data collected (by a `collect $_sdata'
3336 tracepoint action). The remote stub reports support for this packet
3337 to gdb's qSupported query.
3341 Send the current settings of GDB's permission flags.
3345 Send part of the source (textual) form of a tracepoint definition,
3346 which includes location, conditional, and action list.
3348 * The source command now accepts a -s option to force searching for the
3349 script in the source search path even if the script name specifies
3352 * New features in the GDB remote stub, GDBserver
3354 - GDBserver now support tracepoints (including fast tracepoints, and
3355 static tracepoints). The feature is currently supported by the
3356 i386-linux and amd64-linux builds. See the "Tracepoints support
3357 in gdbserver" section in the manual for more information.
3359 GDBserver JIT compiles the tracepoint's conditional agent
3360 expression bytecode into native code whenever possible for low
3361 overhead dynamic tracepoints conditionals. For such tracepoints,
3362 an expression that examines program state is evaluated when the
3363 tracepoint is reached, in order to determine whether to capture
3364 trace data. If the condition is simple and false, processing the
3365 tracepoint finishes very quickly and no data is gathered.
3367 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3368 for static tracepoints support.
3370 - GDBserver now supports x86_64 Windows 64-bit debugging.
3372 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3373 it understands register description.
3375 * The --batch flag now disables pagination and queries.
3377 * X86 general purpose registers
3379 GDB now supports reading/writing byte, word and double-word x86
3380 general purpose registers directly. This means you can use, say,
3381 $ah or $ax to refer, respectively, to the byte register AH and
3382 16-bit word register AX that are actually portions of the 32-bit
3383 register EAX or 64-bit register RAX.
3385 * The `commands' command now accepts a range of breakpoints to modify.
3386 A plain `commands' following a command that creates multiple
3387 breakpoints affects all the breakpoints set by that command. This
3388 applies to breakpoints set by `rbreak', and also applies when a
3389 single `break' command creates multiple breakpoints (e.g.,
3390 breakpoints on overloaded c++ functions).
3392 * The `rbreak' command now accepts a filename specification as part of
3393 its argument, limiting the functions selected by the regex to those
3394 in the specified file.
3396 * Support for remote debugging Windows and SymbianOS shared libraries
3397 from Unix hosts has been improved. Non Windows GDB builds now can
3398 understand target reported file names that follow MS-DOS based file
3399 system semantics, such as file names that include drive letters and
3400 use the backslash character as directory separator. This makes it
3401 possible to transparently use the "set sysroot" and "set
3402 solib-search-path" on Unix hosts to point as host copies of the
3403 target's shared libraries. See the new command "set
3404 target-file-system-kind" described below, and the "Commands to
3405 specify files" section in the user manual for more information.
3409 eval template, expressions...
3410 Convert the values of one or more expressions under the control
3411 of the string template to a command line, and call it.
3413 set target-file-system-kind unix|dos-based|auto
3414 show target-file-system-kind
3415 Set or show the assumed file system kind for target reported file
3418 save breakpoints <filename>
3419 Save all current breakpoint definitions to a file suitable for use
3420 in a later debugging session. To read the saved breakpoint
3421 definitions, use the `source' command.
3423 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3426 info static-tracepoint-markers
3427 Display information about static tracepoint markers in the target.
3429 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3430 Define a static tracepoint by probing a marker at the given
3431 function, line, address, or marker ID.
3435 Enable and disable observer mode.
3437 set may-write-registers on|off
3438 set may-write-memory on|off
3439 set may-insert-breakpoints on|off
3440 set may-insert-tracepoints on|off
3441 set may-insert-fast-tracepoints on|off
3442 set may-interrupt on|off
3443 Set individual permissions for GDB effects on the target. Note that
3444 some of these settings can have undesirable or surprising
3445 consequences, particularly when changed in the middle of a session.
3446 For instance, disabling the writing of memory can prevent
3447 breakpoints from being inserted, cause single-stepping to fail, or
3448 even crash your program, if you disable after breakpoints have been
3449 inserted. However, GDB should not crash.
3451 set record memory-query on|off
3452 show record memory-query
3453 Control whether to stop the inferior if memory changes caused
3454 by an instruction cannot be recorded.
3459 The disassemble command now supports "start,+length" form of two arguments.
3463 ** GDB now provides a new directory location, called the python directory,
3464 where Python scripts written for GDB can be installed. The location
3465 of that directory is <data-directory>/python, where <data-directory>
3466 is the GDB data directory. For more details, see section `Scripting
3467 GDB using Python' in the manual.
3469 ** The GDB Python API now has access to breakpoints, symbols, symbol
3470 tables, program spaces, inferiors, threads and frame's code blocks.
3471 Additionally, GDB Parameters can now be created from the API, and
3472 manipulated via set/show in the CLI.
3474 ** New functions gdb.target_charset, gdb.target_wide_charset,
3475 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3477 ** New exception gdb.GdbError.
3479 ** Pretty-printers are now also looked up in the current program space.
3481 ** Pretty-printers can now be individually enabled and disabled.
3483 ** GDB now looks for names of Python scripts to auto-load in a
3484 special section named `.debug_gdb_scripts', in addition to looking
3485 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3487 * Tracepoint actions were unified with breakpoint commands. In particular,
3488 there are no longer differences in "info break" output for breakpoints and
3489 tracepoints and the "commands" command can be used for both tracepoints and
3490 regular breakpoints.
3494 ARM Symbian arm*-*-symbianelf*
3496 * D language support.
3497 GDB now supports debugging programs written in the D programming
3500 * GDB now supports the extended ptrace interface for PowerPC which is
3501 available since Linux kernel version 2.6.34. This automatically enables
3502 any hardware breakpoints and additional hardware watchpoints available in
3503 the processor. The old ptrace interface exposes just one hardware
3504 watchpoint and no hardware breakpoints.
3506 * GDB is now able to use the Data Value Compare (DVC) register available on
3507 embedded PowerPC processors to implement in hardware simple watchpoint
3508 conditions of the form:
3510 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3512 This works in native GDB running on Linux kernels with the extended ptrace
3513 interface mentioned above.
3515 *** Changes in GDB 7.1
3519 ** Namespace Support
3521 GDB now supports importing of namespaces in C++. This enables the
3522 user to inspect variables from imported namespaces. Support for
3523 namepace aliasing has also been added. So, if a namespace is
3524 aliased in the current scope (e.g. namepace C=A; ) the user can
3525 print variables using the alias (e.g. (gdb) print C::x).
3529 All known bugs relating to the printing of virtual base class were
3530 fixed. It is now possible to call overloaded static methods using a
3535 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3536 and reinterpret_cast<> are now handled by the C++ expression parser.
3540 Xilinx MicroBlaze microblaze-*-*
3545 Xilinx MicroBlaze microblaze
3548 * Multi-program debugging.
3550 GDB now has support for multi-program (a.k.a. multi-executable or
3551 multi-exec) debugging. This allows for debugging multiple inferiors
3552 simultaneously each running a different program under the same GDB
3553 session. See "Debugging Multiple Inferiors and Programs" in the
3554 manual for more information. This implied some user visible changes
3555 in the multi-inferior support. For example, "info inferiors" now
3556 lists inferiors that are not running yet or that have exited
3557 already. See also "New commands" and "New options" below.
3559 * New tracing features
3561 GDB's tracepoint facility now includes several new features:
3563 ** Trace state variables
3565 GDB tracepoints now include support for trace state variables, which
3566 are variables managed by the target agent during a tracing
3567 experiment. They are useful for tracepoints that trigger each
3568 other, so for instance one tracepoint can count hits in a variable,
3569 and then a second tracepoint has a condition that is true when the
3570 count reaches a particular value. Trace state variables share the
3571 $-syntax of GDB convenience variables, and can appear in both
3572 tracepoint actions and condition expressions. Use the "tvariable"
3573 command to create, and "info tvariables" to view; see "Trace State
3574 Variables" in the manual for more detail.
3578 GDB now includes an option for defining fast tracepoints, which
3579 targets may implement more efficiently, such as by installing a jump
3580 into the target agent rather than a trap instruction. The resulting
3581 speedup can be by two orders of magnitude or more, although the
3582 tradeoff is that some program locations on some target architectures
3583 might not allow fast tracepoint installation, for instance if the
3584 instruction to be replaced is shorter than the jump. To request a
3585 fast tracepoint, use the "ftrace" command, with syntax identical to
3586 the regular trace command.
3588 ** Disconnected tracing
3590 It is now possible to detach GDB from the target while it is running
3591 a trace experiment, then reconnect later to see how the experiment
3592 is going. In addition, a new variable disconnected-tracing lets you
3593 tell the target agent whether to continue running a trace if the
3594 connection is lost unexpectedly.
3598 GDB now has the ability to save the trace buffer into a file, and
3599 then use that file as a target, similarly to you can do with
3600 corefiles. You can select trace frames, print data that was
3601 collected in them, and use tstatus to display the state of the
3602 tracing run at the moment that it was saved. To create a trace
3603 file, use "tsave <filename>", and to use it, do "target tfile
3606 ** Circular trace buffer
3608 You can ask the target agent to handle the trace buffer as a
3609 circular buffer, discarding the oldest trace frames to make room for
3610 newer ones, by setting circular-trace-buffer to on. This feature may
3611 not be available for all target agents.
3616 The disassemble command, when invoked with two arguments, now requires
3617 the arguments to be comma-separated.
3620 The info variables command now displays variable definitions. Files
3621 which only declare a variable are not shown.
3624 The source command is now capable of sourcing Python scripts.
3625 This feature is dependent on the debugger being build with Python
3628 Related to this enhancement is also the introduction of a new command
3629 "set script-extension" (see below).
3631 * New commands (for set/show, see "New options" below)
3633 record save [<FILENAME>]
3634 Save a file (in core file format) containing the process record
3635 execution log for replay debugging at a later time.
3637 record restore <FILENAME>
3638 Restore the process record execution log that was saved at an
3639 earlier time, for replay debugging.
3641 add-inferior [-copies <N>] [-exec <FILENAME>]
3644 clone-inferior [-copies <N>] [ID]
3645 Make a new inferior ready to execute the same program another
3646 inferior has loaded.
3651 maint info program-spaces
3652 List the program spaces loaded into GDB.
3654 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3655 show remote interrupt-sequence
3656 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3657 as the sequence to the remote target in order to interrupt the execution.
3658 Ctrl-C is a default. Some system prefers BREAK which is high level of
3659 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3660 Magic SysRq g. It is BREAK signal and character 'g'.
3662 set remote interrupt-on-connect [on | off]
3663 show remote interrupt-on-connect
3664 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3665 remote target when gdb connects to it. This is needed when you debug
3668 set remotebreak [on | off]
3670 Deprecated. Use "set/show remote interrupt-sequence" instead.
3672 tvariable $NAME [ = EXP ]
3673 Create or modify a trace state variable.
3676 List trace state variables and their values.
3678 delete tvariable $NAME ...
3679 Delete one or more trace state variables.
3682 Evaluate the given expressions without collecting anything into the
3683 trace buffer. (Valid in tracepoint actions only.)
3685 ftrace FN / FILE:LINE / *ADDR
3686 Define a fast tracepoint at the given function, line, or address.
3688 * New expression syntax
3690 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3691 GDB now parses 0b101010 identically with 42.
3695 set follow-exec-mode new|same
3696 show follow-exec-mode
3697 Control whether GDB reuses the same inferior across an exec call or
3698 creates a new one. This is useful to be able to restart the old
3699 executable after the inferior having done an exec call.
3701 set default-collect EXPR, ...
3702 show default-collect
3703 Define a list of expressions to be collected at each tracepoint.
3704 This is a useful way to ensure essential items are not overlooked,
3705 such as registers or a critical global variable.
3707 set disconnected-tracing
3708 show disconnected-tracing
3709 If set to 1, the target is instructed to continue tracing if it
3710 loses its connection to GDB. If 0, the target is to stop tracing
3713 set circular-trace-buffer
3714 show circular-trace-buffer
3715 If set to on, the target is instructed to use a circular trace buffer
3716 and discard the oldest trace frames instead of stopping the trace due
3717 to a full trace buffer. If set to off, the trace stops when the buffer
3718 fills up. Some targets may not support this.
3720 set script-extension off|soft|strict
3721 show script-extension
3722 If set to "off", the debugger does not perform any script language
3723 recognition, and all sourced files are assumed to be GDB scripts.
3724 If set to "soft" (the default), files are sourced according to
3725 filename extension, falling back to GDB scripts if the first
3727 If set to "strict", files are sourced according to filename extension.
3729 set ada trust-PAD-over-XVS on|off
3730 show ada trust-PAD-over-XVS
3731 If off, activate a workaround against a bug in the debugging information
3732 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3733 the GCC sources for more information about the GNAT encoding and
3734 PAD types in particular). It is always safe to set this option to
3735 off, but this introduces a slight performance penalty. The default
3738 * Python API Improvements
3740 ** GDB provides the new class gdb.LazyString. This is useful in
3741 some pretty-printing cases. The new method gdb.Value.lazy_string
3742 provides a simple way to create objects of this type.
3744 ** The fields returned by gdb.Type.fields now have an
3745 `is_base_class' attribute.
3747 ** The new method gdb.Type.range returns the range of an array type.
3749 ** The new method gdb.parse_and_eval can be used to parse and
3750 evaluate an expression.
3752 * New remote packets
3755 Define a trace state variable.
3758 Get the current value of a trace state variable.
3761 Set desired tracing behavior upon disconnection.
3764 Set the trace buffer to be linear or circular.
3767 Get data about the tracepoints currently in use.
3771 Process record now works correctly with hardware watchpoints.
3773 Multiple bug fixes have been made to the mips-irix port, making it
3774 much more reliable. In particular:
3775 - Debugging threaded applications is now possible again. Previously,
3776 GDB would hang while starting the program, or while waiting for
3777 the program to stop at a breakpoint.
3778 - Attaching to a running process no longer hangs.
3779 - An error occurring while loading a core file has been fixed.
3780 - Changing the value of the PC register now works again. This fixes
3781 problems observed when using the "jump" command, or when calling
3782 a function from GDB, or even when assigning a new value to $pc.
3783 - With the "finish" and "return" commands, the return value for functions
3784 returning a small array is now correctly printed.
3785 - It is now possible to break on shared library code which gets executed
3786 during a shared library init phase (code executed while executing
3787 their .init section). Previously, the breakpoint would have no effect.
3788 - GDB is now able to backtrace through the signal handler for
3789 non-threaded programs.
3791 PIE (Position Independent Executable) programs debugging is now supported.
3792 This includes debugging execution of PIC (Position Independent Code) shared
3793 libraries although for that, it should be possible to run such libraries as an
3796 *** Changes in GDB 7.0
3798 * GDB now has an interface for JIT compilation. Applications that
3799 dynamically generate code can create symbol files in memory and register
3800 them with GDB. For users, the feature should work transparently, and
3801 for JIT developers, the interface is documented in the GDB manual in the
3802 "JIT Compilation Interface" chapter.
3804 * Tracepoints may now be conditional. The syntax is as for
3805 breakpoints; either an "if" clause appended to the "trace" command,
3806 or the "condition" command is available. GDB sends the condition to
3807 the target for evaluation using the same bytecode format as is used
3808 for tracepoint actions.
3810 * The disassemble command now supports: an optional /r modifier, print the
3811 raw instructions in hex as well as in symbolic form, and an optional /m
3812 modifier to print mixed source+assembly.
3814 * Process record and replay
3816 In a architecture environment that supports ``process record and
3817 replay'', ``process record and replay'' target can record a log of
3818 the process execution, and replay it with both forward and reverse
3821 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3822 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3823 set execution-direction {forward|reverse}, for targets that support
3826 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3827 feature is available with a native GDB running on kernel version
3830 * GDB now has support for multi-byte and wide character sets on the
3831 target. Strings whose character type is wchar_t, char16_t, or
3832 char32_t are now correctly printed. GDB supports wide- and unicode-
3833 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3834 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3835 `printf'. This feature requires iconv to work properly; if your
3836 system does not have a working iconv, GDB can use GNU libiconv. See
3837 the installation instructions for more information.
3839 * GDB now supports automatic retrieval of shared library files from
3840 remote targets. To use this feature, specify a system root that begins
3841 with the `remote:' prefix, either via the `set sysroot' command or via
3842 the `--with-sysroot' configure-time option.
3844 * "info sharedlibrary" now takes an optional regex of libraries to show,
3845 and it now reports if a shared library has no debugging information.
3847 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3848 now complete on file names.
3850 * When completing in expressions, gdb will attempt to limit
3851 completions to allowable structure or union fields, where appropriate.
3852 For instance, consider:
3854 # struct example { int f1; double f2; };
3855 # struct example variable;
3858 If the user types TAB at the end of this command line, the available
3859 completions will be "f1" and "f2".
3861 * Inlined functions are now supported. They show up in backtraces, and
3862 the "step", "next", and "finish" commands handle them automatically.
3864 * GDB now supports the token-splicing (##) and stringification (#)
3865 operators when expanding macros. It also supports variable-arity
3868 * GDB now supports inspecting extra signal information, exported by
3869 the new $_siginfo convenience variable. The feature is currently
3870 implemented on linux ARM, i386 and amd64.
3872 * GDB can now display the VFP floating point registers and NEON vector
3873 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3874 can provide these registers (requires Linux 2.6.30 or later). Remote
3875 and simulator targets may also provide them.
3877 * New remote packets
3880 Search memory for a sequence of bytes.
3883 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3884 operation over reliable transport links. Use of this packet is
3885 controlled by the `set remote noack-packet' command.
3888 Kill the process with the specified process ID. Use this in preference
3889 to `k' when multiprocess protocol extensions are supported.
3892 Obtains additional operating system information
3896 Read or write additional signal information.
3898 * Removed remote protocol undocumented extension
3900 An undocumented extension to the remote protocol's `S' stop reply
3901 packet that permited the stub to pass a process id was removed.
3902 Remote servers should use the `T' stop reply packet instead.
3904 * GDB now supports multiple function calling conventions according to the
3905 DWARF-2 DW_AT_calling_convention function attribute.
3907 * The SH target utilizes the aforementioned change to distinguish between gcc
3908 and Renesas calling convention. It also adds the new CLI commands
3909 `set/show sh calling-convention'.
3911 * GDB can now read compressed debug sections, as produced by GNU gold
3912 with the --compress-debug-sections=zlib flag.
3914 * 64-bit core files are now supported on AIX.
3916 * Thread switching is now supported on Tru64.
3918 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3919 which will be allocated using malloc later in program execution.
3921 * The qXfer:libraries:read remote procotol packet now allows passing a
3922 list of section offsets.
3924 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3925 conditions handling signals delivered during attach or thread creation
3926 have also been fixed.
3928 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3929 From the user's standpoint, all unqualified instances of True and False
3930 are treated as the standard definitions, regardless of context.
3932 * GDB now parses C++ symbol and type names more flexibly. For
3935 template<typename T> class C { };
3938 GDB will now correctly handle all of:
3940 ptype C<char const *>
3941 ptype C<char const*>
3942 ptype C<const char *>
3943 ptype C<const char*>
3945 * New features in the GDB remote stub, gdbserver
3947 - The "--wrapper" command-line argument tells gdbserver to use a
3948 wrapper program to launch programs for debugging.
3950 - On PowerPC and S/390 targets, it is now possible to use a single
3951 gdbserver executable to debug both 32-bit and 64-bit programs.
3952 (This requires gdbserver itself to be built as a 64-bit executable.)
3954 - gdbserver uses the new noack protocol mode for TCP connections to
3955 reduce communications latency, if also supported and enabled in GDB.
3957 - Support for the sparc64-linux-gnu target is now included in
3960 - The amd64-linux build of gdbserver now supports debugging both
3961 32-bit and 64-bit programs.
3963 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3964 now support hardware watchpoints, and will use them automatically
3969 GDB now has support for scripting using Python. Whether this is
3970 available is determined at configure time.
3972 New GDB commands can now be written in Python.
3974 * Ada tasking support
3976 Ada tasks can now be inspected in GDB. The following commands have
3980 Print the list of Ada tasks.
3982 Print detailed information about task number N.
3984 Print the task number of the current task.
3986 Switch the context of debugging to task number N.
3988 * Support for user-defined prefixed commands. The "define" command can
3989 add new commands to existing prefixes, e.g. "target".
3991 * Multi-inferior, multi-process debugging.
3993 GDB now has generalized support for multi-inferior debugging. See
3994 "Debugging Multiple Inferiors" in the manual for more information.
3995 Although availability still depends on target support, the command
3996 set is more uniform now. The GNU/Linux specific multi-forks support
3997 has been migrated to this new framework. This implied some user
3998 visible changes; see "New commands" and also "Removed commands"
4001 * Target descriptions can now describe the target OS ABI. See the
4002 "Target Description Format" section in the user manual for more
4005 * Target descriptions can now describe "compatible" architectures
4006 to indicate that the target can execute applications for a different
4007 architecture in addition to those for the main target architecture.
4008 See the "Target Description Format" section in the user manual for
4011 * Multi-architecture debugging.
4013 GDB now includes general supports for debugging applications on
4014 hybrid systems that use more than one single processor architecture
4015 at the same time. Each such hybrid architecture still requires
4016 specific support to be added. The only hybrid architecture supported
4017 in this version of GDB is the Cell Broadband Engine.
4019 * GDB now supports integrated debugging of Cell/B.E. applications that
4020 use both the PPU and SPU architectures. To enable support for hybrid
4021 Cell/B.E. debugging, you need to configure GDB to support both the
4022 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4023 --enable-targets configure option.
4025 * Non-stop mode debugging.
4027 For some targets, GDB now supports an optional mode of operation in
4028 which you can examine stopped threads while other threads continue
4029 to execute freely. This is referred to as non-stop mode, with the
4030 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4031 section in the user manual for more information.
4033 To be able to support remote non-stop debugging, a remote stub needs
4034 to implement the non-stop mode remote protocol extensions, as
4035 described in the "Remote Non-Stop" section of the user manual. The
4036 GDB remote stub, gdbserver, has been adjusted to support these
4037 extensions on linux targets.
4039 * New commands (for set/show, see "New options" below)
4041 catch syscall [NAME(S) | NUMBER(S)]
4042 Catch system calls. Arguments, which should be names of system
4043 calls or their numbers, mean catch only those syscalls. Without
4044 arguments, every syscall will be caught. When the inferior issues
4045 any of the specified syscalls, GDB will stop and announce the system
4046 call, both when it is called and when its call returns. This
4047 feature is currently available with a native GDB running on the
4048 Linux Kernel, under the following architectures: x86, x86_64,
4049 PowerPC and PowerPC64.
4051 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4053 Search memory for a sequence of bytes.
4055 maint set python print-stack
4056 maint show python print-stack
4057 Show a stack trace when an error is encountered in a Python script.
4060 Invoke CODE by passing it to the Python interpreter.
4065 These allow macros to be defined, undefined, and listed
4069 Show operating system information about processes.
4072 List the inferiors currently under GDB's control.
4075 Switch focus to inferior number NUM.
4078 Detach from inferior number NUM.
4081 Kill inferior number NUM.
4085 set spu stop-on-load
4086 show spu stop-on-load
4087 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4089 set spu auto-flush-cache
4090 show spu auto-flush-cache
4091 Control whether to automatically flush the software-managed cache
4092 during Cell/B.E. debugging.
4094 set sh calling-convention
4095 show sh calling-convention
4096 Control the calling convention used when calling SH target functions.
4099 show debug timestamp
4100 Control display of timestamps with GDB debugging output.
4102 set disassemble-next-line
4103 show disassemble-next-line
4104 Control display of disassembled source lines or instructions when
4107 set remote noack-packet
4108 show remote noack-packet
4109 Set/show the use of remote protocol QStartNoAckMode packet. See above
4110 under "New remote packets."
4112 set remote query-attached-packet
4113 show remote query-attached-packet
4114 Control use of remote protocol `qAttached' (query-attached) packet.
4116 set remote read-siginfo-object
4117 show remote read-siginfo-object
4118 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4121 set remote write-siginfo-object
4122 show remote write-siginfo-object
4123 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4126 set remote reverse-continue
4127 show remote reverse-continue
4128 Control use of remote protocol 'bc' (reverse-continue) packet.
4130 set remote reverse-step
4131 show remote reverse-step
4132 Control use of remote protocol 'bs' (reverse-step) packet.
4134 set displaced-stepping
4135 show displaced-stepping
4136 Control displaced stepping mode. Displaced stepping is a way to
4137 single-step over breakpoints without removing them from the debuggee.
4138 Also known as "out-of-line single-stepping".
4141 show debug displaced
4142 Control display of debugging info for displaced stepping.
4144 maint set internal-error
4145 maint show internal-error
4146 Control what GDB does when an internal error is detected.
4148 maint set internal-warning
4149 maint show internal-warning
4150 Control what GDB does when an internal warning is detected.
4155 Use a wrapper program to launch programs for debugging.
4157 set multiple-symbols (all|ask|cancel)
4158 show multiple-symbols
4159 The value of this variable can be changed to adjust the debugger behavior
4160 when an expression or a breakpoint location contains an ambiguous symbol
4161 name (an overloaded function name, for instance).
4163 set breakpoint always-inserted
4164 show breakpoint always-inserted
4165 Keep breakpoints always inserted in the target, as opposed to inserting
4166 them when resuming the target, and removing them when the target stops.
4167 This option can improve debugger performance on slow remote targets.
4169 set arm fallback-mode (arm|thumb|auto)
4170 show arm fallback-mode
4171 set arm force-mode (arm|thumb|auto)
4173 These commands control how ARM GDB determines whether instructions
4174 are ARM or Thumb. The default for both settings is auto, which uses
4175 the current CPSR value for instructions without symbols; previous
4176 versions of GDB behaved as if "set arm fallback-mode arm".
4178 set disable-randomization
4179 show disable-randomization
4180 Standalone programs run with the virtual address space randomization enabled
4181 by default on some platforms. This option keeps the addresses stable across
4182 multiple debugging sessions.
4186 Control whether other threads are stopped or not when some thread hits
4191 Requests that asynchronous execution is enabled in the target, if available.
4192 In this case, it's possible to resume target in the background, and interact
4193 with GDB while the target is running. "show target-async" displays the
4194 current state of asynchronous execution of the target.
4196 set target-wide-charset
4197 show target-wide-charset
4198 The target-wide-charset is the name of the character set that GDB
4199 uses when printing characters whose type is wchar_t.
4201 set tcp auto-retry (on|off)
4203 set tcp connect-timeout
4204 show tcp connect-timeout
4205 These commands allow GDB to retry failed TCP connections to a remote stub
4206 with a specified timeout period; this is useful if the stub is launched
4207 in parallel with GDB but may not be ready to accept connections immediately.
4209 set libthread-db-search-path
4210 show libthread-db-search-path
4211 Control list of directories which GDB will search for appropriate
4214 set schedule-multiple (on|off)
4215 show schedule-multiple
4216 Allow GDB to resume all threads of all processes or only threads of
4217 the current process.
4221 Use more aggressive caching for accesses to the stack. This improves
4222 performance of remote debugging (particularly backtraces) without
4223 affecting correctness.
4225 set interactive-mode (on|off|auto)
4226 show interactive-mode
4227 Control whether GDB runs in interactive mode (on) or not (off).
4228 When in interactive mode, GDB waits for the user to answer all
4229 queries. Otherwise, GDB does not wait and assumes the default
4230 answer. When set to auto (the default), GDB determines which
4231 mode to use based on the stdin settings.
4236 For program forks, this is replaced by the new more generic `info
4237 inferiors' command. To list checkpoints, you can still use the
4238 `info checkpoints' command, which was an alias for the `info forks'
4242 Replaced by the new `inferior' command. To switch between
4243 checkpoints, you can still use the `restart' command, which was an
4244 alias for the `fork' command.
4247 This is removed, since some targets don't have a notion of
4248 processes. To switch between processes, you can still use the
4249 `inferior' command using GDB's own inferior number.
4252 For program forks, this is replaced by the new more generic `kill
4253 inferior' command. To delete a checkpoint, you can still use the
4254 `delete checkpoint' command, which was an alias for the `delete
4258 For program forks, this is replaced by the new more generic `detach
4259 inferior' command. To detach a checkpoint, you can still use the
4260 `detach checkpoint' command, which was an alias for the `detach
4263 * New native configurations
4265 x86/x86_64 Darwin i[34567]86-*-darwin*
4267 x86_64 MinGW x86_64-*-mingw*
4271 Lattice Mico32 lm32-*
4272 x86 DICOS i[34567]86-*-dicos*
4273 x86_64 DICOS x86_64-*-dicos*
4276 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4277 (mingw32ce) debugging.
4283 These commands were actually not implemented on any target.
4285 *** Changes in GDB 6.8
4287 * New native configurations
4289 NetBSD/hppa hppa*-*netbsd*
4290 Xtensa GNU/Linux xtensa*-*-linux*
4294 NetBSD/hppa hppa*-*-netbsd*
4295 Xtensa GNU/Lunux xtensa*-*-linux*
4297 * Change in command line behavior -- corefiles vs. process ids.
4299 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4300 attaching to process NUMBER fails, GDB no longer attempts to open a
4301 core file named NUMBER. Attaching to a program using the -c option
4302 is no longer supported. Instead, use the '-p' or '--pid' options.
4304 * GDB can now be built as a native debugger for debugging Windows x86
4305 (mingw32) Portable Executable (PE) programs.
4307 * Pending breakpoints no longer change their number when their address
4310 * GDB now supports breakpoints with multiple locations,
4311 including breakpoints on C++ constructors, inside C++ templates,
4312 and in inlined functions.
4314 * GDB's ability to debug optimized code has been improved. GDB more
4315 accurately identifies function bodies and lexical blocks that occupy
4316 more than one contiguous range of addresses.
4318 * Target descriptions can now describe registers for PowerPC.
4320 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4321 registers on PowerPC targets.
4323 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4324 targets even when the libthread_db library is not available.
4326 * The GDB remote stub, gdbserver, now supports the new file transfer
4327 commands (remote put, remote get, and remote delete).
4329 * The GDB remote stub, gdbserver, now supports run and attach in
4330 extended-remote mode.
4332 * hppa*64*-*-hpux11* target broken
4333 The debugger is unable to start a program and fails with the following
4334 error: "Error trying to get information about dynamic linker".
4335 The gdb-6.7 release is also affected.
4337 * GDB now supports the --enable-targets= configure option to allow
4338 building a single GDB executable that supports multiple remote
4339 target architectures.
4341 * GDB now supports debugging C and C++ programs which use the
4342 Decimal Floating Point extension. In addition, the PowerPC target
4343 now has a set of pseudo-registers to inspect decimal float values
4344 stored in two consecutive float registers.
4346 * The -break-insert MI command can optionally create pending
4349 * Improved support for debugging Ada
4350 Many improvements to the Ada language support have been made. These
4352 - Better support for Ada2005 interface types
4353 - Improved handling of arrays and slices in general
4354 - Better support for Taft-amendment types
4355 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4357 - Improved command completion in Ada
4360 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4365 set print frame-arguments (all|scalars|none)
4366 show print frame-arguments
4367 The value of this variable can be changed to control which argument
4368 values should be printed by the debugger when displaying a frame.
4373 Transfer files to and from a remote target, and delete remote files.
4380 Transfer files to and from a remote target, and delete remote files.
4382 * New remote packets
4389 Open, close, read, write, and delete files on the remote system.
4392 Attach to an existing process on the remote system, in extended-remote
4396 Run a new process on the remote system, in extended-remote mode.
4398 *** Changes in GDB 6.7
4400 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4401 bfd, libiberty and opcodes, as revealed by static analysis donated by
4402 Coverity, Inc. (http://scan.coverity.com).
4404 * When looking up multiply-defined global symbols, GDB will now prefer the
4405 symbol definition in the current shared library if it was built using the
4406 -Bsymbolic linker option.
4408 * When the Text User Interface (TUI) is not configured, GDB will now
4409 recognize the -tui command-line option and print a message that the TUI
4412 * The GDB remote stub, gdbserver, now has lower overhead for high
4413 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4415 * GDB for MIPS targets now autodetects whether a remote target provides
4416 32-bit or 64-bit register values.
4418 * Support for C++ member pointers has been improved.
4420 * GDB now understands XML target descriptions, which specify the
4421 target's overall architecture. GDB can read a description from
4422 a local file or over the remote serial protocol.
4424 * Vectors of single-byte data use a new integer type which is not
4425 automatically displayed as character or string data.
4427 * The /s format now works with the print command. It displays
4428 arrays of single-byte integers and pointers to single-byte integers
4431 * Target descriptions can now describe target-specific registers,
4432 for architectures which have implemented the support (currently
4433 only ARM, M68K, and MIPS).
4435 * GDB and the GDB remote stub, gdbserver, now support the XScale
4438 * The GDB remote stub, gdbserver, has been updated to support
4439 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4440 has been rewritten to use the standard GDB remote protocol.
4442 * GDB can now step into C++ functions which are called through thunks.
4444 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4446 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4447 layout. It also supports a TextSeg= and DataSeg= response when only
4448 segment base addresses (rather than offsets) are available.
4450 * The /i format now outputs any trailing branch delay slot instructions
4451 immediately following the last instruction within the count specified.
4453 * The GDB remote protocol "T" stop reply packet now supports a
4454 "library" response. Combined with the new "qXfer:libraries:read"
4455 packet, this response allows GDB to debug shared libraries on targets
4456 where the operating system manages the list of loaded libraries (e.g.
4457 Windows and SymbianOS).
4459 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4460 (DLLs) on Windows and Windows CE targets.
4462 * GDB now supports a faster verification that a .debug file matches its binary
4463 according to its build-id signature, if the signature is present.
4469 Enable or disable hardware flow control (RTS/CTS) on the serial port
4470 when debugging using remote targets.
4472 set mem inaccessible-by-default
4473 show mem inaccessible-by-default
4474 If the target supplies a memory map, for instance via the remote
4475 protocol's "qXfer:memory-map:read" packet, setting this variable
4476 prevents GDB from accessing memory outside the memory map. This
4477 is useful for targets with memory mapped registers or which react
4478 badly to accesses of unmapped address space.
4480 set breakpoint auto-hw
4481 show breakpoint auto-hw
4482 If the target supplies a memory map, for instance via the remote
4483 protocol's "qXfer:memory-map:read" packet, setting this variable
4484 lets GDB use hardware breakpoints automatically for memory regions
4485 where it can not use software breakpoints. This covers both the
4486 "break" command and internal breakpoints used for other commands
4487 including "next" and "finish".
4490 catch exception unhandled
4491 Stop the program execution when Ada exceptions are raised.
4494 Stop the program execution when an Ada assertion failed.
4498 Set an alternate system root for target files. This is a more
4499 general version of "set solib-absolute-prefix", which is now
4500 an alias to "set sysroot".
4503 Provide extended SPU facility status information. This set of
4504 commands is available only when debugging the Cell/B.E. SPU
4507 * New native configurations
4509 OpenBSD/sh sh*-*openbsd*
4512 unset tdesc filename
4514 Use the specified local file as an XML target description, and do
4515 not query the target for its built-in description.
4519 OpenBSD/sh sh*-*-openbsd*
4520 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4521 Toshiba Media Processor mep-elf
4523 * New remote packets
4526 Ignore the specified signals; pass them directly to the debugged program
4527 without stopping other threads or reporting them to GDB.
4529 qXfer:features:read:
4530 Read an XML target description from the target, which describes its
4535 Read or write contents of an spufs file on the target system. These
4536 packets are available only on the Cell/B.E. SPU architecture.
4538 qXfer:libraries:read:
4539 Report the loaded shared libraries. Combined with new "T" packet
4540 response, this packet allows GDB to debug shared libraries on
4541 targets where the operating system manages the list of loaded
4542 libraries (e.g. Windows and SymbianOS).
4546 Support for these obsolete configurations has been removed.
4554 i[34567]86-*-lynxos*
4555 i[34567]86-*-netware*
4556 i[34567]86-*-sco3.2v5*
4557 i[34567]86-*-sco3.2v4*
4559 i[34567]86-*-sysv4.2*
4562 i[34567]86-*-unixware2*
4563 i[34567]86-*-unixware*
4572 * Other removed features
4579 Various m68k-only ROM monitors.
4586 Various Renesas ROM monitors and debugging interfaces for SH and
4591 Support for a Macraigor serial interface to on-chip debugging.
4592 GDB does not directly support the newer parallel or USB
4597 A debug information format. The predecessor to DWARF 2 and
4598 DWARF 3, which are still supported.
4600 Support for the HP aCC compiler on HP-UX/PA-RISC
4602 SOM-encapsulated symbolic debugging information, automatic
4603 invocation of pxdb, and the aCC custom C++ ABI. This does not
4604 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4605 with aCC can still be debugged on an assembly level.
4607 MIPS ".pdr" sections
4609 A MIPS-specific format used to describe stack frame layout
4610 in debugging information.
4614 GDB could work with an older version of Guile to debug
4615 the interpreter and Scheme programs running in it.
4617 set mips stack-arg-size
4618 set mips saved-gpreg-size
4620 Use "set mips abi" to control parameter passing for MIPS.
4622 *** Changes in GDB 6.6
4627 Cell Broadband Engine SPU spu-elf
4629 * GDB can now be configured as a cross-debugger targeting native Windows
4630 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4631 running on a Windows system over TCP/IP to debug Windows programs.
4633 * The GDB remote stub, gdbserver, has been updated to support Windows and
4634 Cygwin debugging. Both single-threaded and multi-threaded programs are
4637 * The "set trust-readonly-sections" command works again. This command was
4638 broken in GDB 6.3, 6.4, and 6.5.
4640 * The "load" command now supports writing to flash memory, if the remote
4641 stub provides the required support.
4643 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4644 longer requires symbolic debug information (e.g. DWARF-2).
4649 unset substitute-path
4650 show substitute-path
4651 Manage a list of substitution rules that GDB uses to rewrite the name
4652 of the directories where the sources are located. This can be useful
4653 for instance when the sources were moved to a different location
4654 between compilation and debugging.
4658 Print each CLI command as it is executed. Each command is prefixed with
4659 a number of `+' symbols representing the nesting depth.
4660 The source command now has a `-v' option to enable the same feature.
4664 The ARM Demon monitor support (RDP protocol, "target rdp").
4666 Kernel Object Display, an embedded debugging feature which only worked with
4667 an obsolete version of Cisco IOS.
4669 The 'set download-write-size' and 'show download-write-size' commands.
4671 * New remote packets
4674 Tell a stub about GDB client features, and request remote target features.
4675 The first feature implemented is PacketSize, which allows the target to
4676 specify the size of packets it can handle - to minimize the number of
4677 packets required and improve performance when connected to a remote
4681 Fetch an OS auxilliary vector from the remote stub. This packet is a
4682 more efficient replacement for qPart:auxv:read.
4684 qXfer:memory-map:read:
4685 Fetch a memory map from the remote stub, including information about
4686 RAM, ROM, and flash memory devices.
4691 Erase and program a flash memory device.
4693 * Removed remote packets
4696 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4697 used it, and only gdbserver implemented it.
4699 *** Changes in GDB 6.5
4703 Renesas M32C/M16C m32c-elf
4705 Morpho Technologies ms1 ms1-elf
4709 init-if-undefined Initialize a convenience variable, but
4710 only if it doesn't already have a value.
4712 The following commands are presently only implemented for native GNU/Linux:
4714 checkpoint Save a snapshot of the program state.
4716 restart <n> Return the program state to a
4717 previously saved state.
4719 info checkpoints List currently saved checkpoints.
4721 delete-checkpoint <n> Delete a previously saved checkpoint.
4723 set|show detach-on-fork Tell gdb whether to detach from a newly
4724 forked process, or to keep debugging it.
4726 info forks List forks of the user program that
4727 are available to be debugged.
4729 fork <n> Switch to debugging one of several
4730 forks of the user program that are
4731 available to be debugged.
4733 delete-fork <n> Delete a fork from the list of forks
4734 that are available to be debugged (and
4735 kill the forked process).
4737 detach-fork <n> Delete a fork from the list of forks
4738 that are available to be debugged (and
4739 allow the process to continue).
4743 Morpho Technologies ms2 ms1-elf
4745 * Improved Windows host support
4747 GDB now builds as a cross debugger hosted on i686-mingw32, including
4748 native console support, and remote communications using either
4749 network sockets or serial ports.
4751 * Improved Modula-2 language support
4753 GDB can now print most types in the Modula-2 syntax. This includes:
4754 basic types, set types, record types, enumerated types, range types,
4755 pointer types and ARRAY types. Procedure var parameters are correctly
4756 printed and hexadecimal addresses and character constants are also
4757 written in the Modula-2 syntax. Best results can be obtained by using
4758 GNU Modula-2 together with the -gdwarf-2 command line option.
4762 The ARM rdi-share module.
4764 The Netware NLM debug server.
4766 *** Changes in GDB 6.4
4768 * New native configurations
4770 OpenBSD/arm arm*-*-openbsd*
4771 OpenBSD/mips64 mips64-*-openbsd*
4775 Morpho Technologies ms1 ms1-elf
4777 * New command line options
4779 --batch-silent As for --batch, but totally silent.
4780 --return-child-result The debugger will exist with the same value
4781 the child (debugged) program exited with.
4782 --eval-command COMMAND, -ex COMMAND
4783 Execute a single GDB CLI command. This may be
4784 specified multiple times and in conjunction
4785 with the --command (-x) option.
4787 * Deprecated commands removed
4789 The following commands, that were deprecated in 2000, have been
4793 set|show arm disassembly-flavor set|show arm disassembler
4794 othernames set arm disassembler
4795 set|show remotedebug set|show debug remote
4796 set|show archdebug set|show debug arch
4797 set|show eventdebug set|show debug event
4800 * New BSD user-level threads support
4802 It is now possible to debug programs using the user-level threads
4803 library on OpenBSD and FreeBSD. Currently supported (target)
4806 FreeBSD/amd64 x86_64-*-freebsd*
4807 FreeBSD/i386 i386-*-freebsd*
4808 OpenBSD/i386 i386-*-openbsd*
4810 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4811 are not yet supported.
4813 * New support for Matsushita MN10300 w/sim added
4814 (Work in progress). mn10300-elf.
4816 * REMOVED configurations and files
4818 VxWorks and the XDR protocol *-*-vxworks
4819 Motorola MCORE mcore-*-*
4820 National Semiconductor NS32000 ns32k-*-*
4822 * New "set print array-indexes" command
4824 After turning this setting "on", GDB prints the index of each element
4825 when displaying arrays. The default is "off" to preserve the previous
4828 * VAX floating point support
4830 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4832 * User-defined command support
4834 In addition to using $arg0..$arg9 for argument passing, it is now possible
4835 to use $argc to determine now many arguments have been passed. See the
4836 section on user-defined commands in the user manual for more information.
4838 *** Changes in GDB 6.3:
4840 * New command line option
4842 GDB now accepts -l followed by a number to set the timeout for remote
4845 * GDB works with GCC -feliminate-dwarf2-dups
4847 GDB now supports a more compact representation of DWARF-2 debug
4848 information using DW_FORM_ref_addr references. These are produced
4849 by GCC with the option -feliminate-dwarf2-dups and also by some
4850 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4851 to use -feliminate-dwarf2-dups.
4853 * Internationalization
4855 When supported by the host system, GDB will be built with
4856 internationalization (libintl). The task of marking up the sources is
4857 continued, we're looking forward to our first translation.
4861 Initial support for debugging programs compiled with the GNAT
4862 implementation of the Ada programming language has been integrated
4863 into GDB. In this release, support is limited to expression evaluation.
4865 * New native configurations
4867 GNU/Linux/m32r m32r-*-linux-gnu
4871 GDB's remote protocol now includes support for the 'p' packet. This
4872 packet is used to fetch individual registers from a remote inferior.
4874 * END-OF-LIFE registers[] compatibility module
4876 GDB's internal register infrastructure has been completely rewritten.
4877 The new infrastructure making possible the implementation of key new
4878 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4881 GDB 6.3 will be the last release to include the the registers[]
4882 compatibility module that allowed out-of-date configurations to
4883 continue to work. This change directly impacts the following
4893 powerpc bdm protocol
4895 Unless there is activity to revive these configurations, they will be
4896 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4898 * OBSOLETE configurations and files
4900 Configurations that have been declared obsolete in this release have
4901 been commented out. Unless there is activity to revive these
4902 configurations, the next release of GDB will have their sources
4903 permanently REMOVED.
4912 *** Changes in GDB 6.2.1:
4914 * MIPS `break main; run' gave an heuristic-fence-post warning
4916 When attempting to run even a simple program, a warning about
4917 heuristic-fence-post being hit would be reported. This problem has
4920 * MIPS IRIX 'long double' crashed GDB
4922 When examining a long double variable, GDB would get a segmentation
4923 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4924 IRIX long double values).
4928 A bug in the VAX stack code was causing problems with the "next"
4929 command. This problem has been fixed.
4931 *** Changes in GDB 6.2:
4933 * Fix for ``many threads''
4935 On GNU/Linux systems that use the NPTL threads library, a program
4936 rapidly creating and deleting threads would confuse GDB leading to the
4939 ptrace: No such process.
4940 thread_db_get_info: cannot get thread info: generic error
4942 This problem has been fixed.
4944 * "-async" and "-noasync" options removed.
4946 Support for the broken "-noasync" option has been removed (it caused
4949 * New ``start'' command.
4951 This command runs the program until the begining of the main procedure.
4953 * New BSD Kernel Data Access Library (libkvm) interface
4955 Using ``target kvm'' it is now possible to debug kernel core dumps and
4956 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4957 platforms. Currently supported (native-only) configurations are:
4959 FreeBSD/amd64 x86_64-*-freebsd*
4960 FreeBSD/i386 i?86-*-freebsd*
4961 NetBSD/i386 i?86-*-netbsd*
4962 NetBSD/m68k m68*-*-netbsd*
4963 NetBSD/sparc sparc-*-netbsd*
4964 OpenBSD/amd64 x86_64-*-openbsd*
4965 OpenBSD/i386 i?86-*-openbsd*
4966 OpenBSD/m68k m68*-openbsd*
4967 OpenBSD/sparc sparc-*-openbsd*
4969 * Signal trampoline code overhauled
4971 Many generic problems with GDB's signal handling code have been fixed.
4972 These include: backtraces through non-contiguous stacks; recognition
4973 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4974 call; backtrace through a signal trampoline; step into and out of
4975 signal handlers; and single-stepping in the signal trampoline.
4977 Please note that kernel bugs are a limiting factor here. These
4978 features have been shown to work on an s390 GNU/Linux system that
4979 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4981 * Cygwin support for DWARF 2 added.
4983 * New native configurations
4985 GNU/Linux/hppa hppa*-*-linux*
4986 OpenBSD/hppa hppa*-*-openbsd*
4987 OpenBSD/m68k m68*-*-openbsd*
4988 OpenBSD/m88k m88*-*-openbsd*
4989 OpenBSD/powerpc powerpc-*-openbsd*
4990 NetBSD/vax vax-*-netbsd*
4991 OpenBSD/vax vax-*-openbsd*
4993 * END-OF-LIFE frame compatibility module
4995 GDB's internal frame infrastructure has been completely rewritten.
4996 The new infrastructure making it possible to support key new features
4997 including DWARF 2 Call Frame Information. To aid in the task of
4998 migrating old configurations to this new infrastructure, a
4999 compatibility module, that allowed old configurations to continue to
5000 work, was also included.
5002 GDB 6.2 will be the last release to include this frame compatibility
5003 module. This change directly impacts the following configurations:
5013 Unless there is activity to revive these configurations, they will be
5014 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5016 * REMOVED configurations and files
5018 Sun 3, running SunOS 3 m68*-*-sunos3*
5019 Sun 3, running SunOS 4 m68*-*-sunos4*
5020 Sun 2, running SunOS 3 m68000-*-sunos3*
5021 Sun 2, running SunOS 4 m68000-*-sunos4*
5022 Motorola 680x0 running LynxOS m68*-*-lynxos*
5023 AT&T 3b1/Unix pc m68*-att-*
5024 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5025 decstation mips-dec-* mips-little-*
5026 riscos mips-*-riscos* mips-*-sysv*
5027 sonymips mips-sony-*
5028 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5030 *** Changes in GDB 6.1.1:
5032 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5034 The TUI (Text-mode User Interface) is now built as part of a default
5035 GDB configuration. It is enabled by either selecting the TUI with the
5036 command line option "-i=tui" or by running the separate "gdbtui"
5037 program. For more information on the TUI, see the manual "Debugging
5040 * Pending breakpoint support (also included in GDB 6.1)
5042 Support has been added to allow you to specify breakpoints in shared
5043 libraries that have not yet been loaded. If a breakpoint location
5044 cannot be found, and the "breakpoint pending" option is set to auto,
5045 GDB queries you if you wish to make the breakpoint pending on a future
5046 shared-library load. If and when GDB resolves the breakpoint symbol,
5047 the pending breakpoint is removed as one or more regular breakpoints
5050 Pending breakpoints are very useful for GCJ Java debugging.
5052 * Fixed ISO-C build problems
5054 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5055 non ISO-C code that stopped them being built using a more strict ISO-C
5056 compiler (e.g., IBM's C compiler).
5058 * Fixed build problem on IRIX 5
5060 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5061 wasn't able to compile compile on an IRIX 5 system.
5063 * Added execute permission to gdb/gdbserver/configure
5065 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5066 permission. This bug would cause configure to fail on a number of
5067 systems (Solaris, IRIX). Ref: server/519.
5069 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5071 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5072 has been updated to use constant array sizes.
5074 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5076 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5077 its generated DWARF Call Frame Info. This encoding was causing GDB to
5078 panic, that panic has been fixed. Ref: gdb/1628.
5080 * Fixed a problem when examining parameters in shared library code.
5082 When examining parameters in optimized shared library code generated
5083 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5084 not available''. GDB now correctly displays the variable's value.
5086 *** Changes in GDB 6.1:
5088 * Removed --with-mmalloc
5090 Support for the mmalloc memory manager has been removed, as it
5091 conflicted with the internal gdb byte cache.
5093 * Changes in AMD64 configurations
5095 The AMD64 target now includes the %cs and %ss registers. As a result
5096 the AMD64 remote protocol has changed; this affects the floating-point
5097 and SSE registers. If you rely on those registers for your debugging,
5098 you should upgrade gdbserver on the remote side.
5100 * Revised SPARC target
5102 The SPARC target has been completely revised, incorporating the
5103 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5104 support for LynxOS and SunOS 4 has been dropped. Calling functions
5105 from within GDB on operating systems with a non-executable stack
5106 (Solaris, OpenBSD) now works.
5110 GDB has a new C++ demangler which does a better job on the mangled
5111 names generated by current versions of g++. It also runs faster, so
5112 with this and other changes gdb should now start faster on large C++
5115 * DWARF 2 Location Expressions
5117 GDB support for location expressions has been extended to support function
5118 arguments and frame bases. Older versions of GDB could crash when they
5121 * C++ nested types and namespaces
5123 GDB's support for nested types and namespaces in C++ has been
5124 improved, especially if you use the DWARF 2 debugging format. (This
5125 is the default for recent versions of GCC on most platforms.)
5126 Specifically, if you have a class "Inner" defined within a class or
5127 namespace "Outer", then GDB realizes that the class's name is
5128 "Outer::Inner", not simply "Inner". This should greatly reduce the
5129 frequency of complaints about not finding RTTI symbols. In addition,
5130 if you are stopped at inside of a function defined within a namespace,
5131 GDB modifies its name lookup accordingly.
5133 * New native configurations
5135 NetBSD/amd64 x86_64-*-netbsd*
5136 OpenBSD/amd64 x86_64-*-openbsd*
5137 OpenBSD/alpha alpha*-*-openbsd*
5138 OpenBSD/sparc sparc-*-openbsd*
5139 OpenBSD/sparc64 sparc64-*-openbsd*
5141 * New debugging protocols
5143 M32R with SDI protocol m32r-*-elf*
5145 * "set prompt-escape-char" command deleted.
5147 The command "set prompt-escape-char" has been deleted. This command,
5148 and its very obscure effet on GDB's prompt, was never documented,
5149 tested, nor mentioned in the NEWS file.
5151 * OBSOLETE configurations and files
5153 Configurations that have been declared obsolete in this release have
5154 been commented out. Unless there is activity to revive these
5155 configurations, the next release of GDB will have their sources
5156 permanently REMOVED.
5158 Sun 3, running SunOS 3 m68*-*-sunos3*
5159 Sun 3, running SunOS 4 m68*-*-sunos4*
5160 Sun 2, running SunOS 3 m68000-*-sunos3*
5161 Sun 2, running SunOS 4 m68000-*-sunos4*
5162 Motorola 680x0 running LynxOS m68*-*-lynxos*
5163 AT&T 3b1/Unix pc m68*-att-*
5164 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5165 decstation mips-dec-* mips-little-*
5166 riscos mips-*-riscos* mips-*-sysv*
5167 sonymips mips-sony-*
5168 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5170 * REMOVED configurations and files
5172 SGI Irix-4.x mips-sgi-irix4 or iris4
5173 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5174 Z8000 simulator z8k-zilog-none or z8ksim
5175 Matsushita MN10200 w/simulator mn10200-*-*
5176 H8/500 simulator h8500-hitachi-hms or h8500hms
5177 HP/PA running BSD hppa*-*-bsd*
5178 HP/PA running OSF/1 hppa*-*-osf*
5179 HP/PA Pro target hppa*-*-pro*
5180 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5181 386BSD i[3456]86-*-bsd*
5182 Sequent family i[3456]86-sequent-sysv4*
5183 i[3456]86-sequent-sysv*
5184 i[3456]86-sequent-bsd*
5185 SPARC running LynxOS sparc-*-lynxos*
5186 SPARC running SunOS 4 sparc-*-sunos4*
5187 Tsqware Sparclet sparclet-*-*
5188 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5190 *** Changes in GDB 6.0:
5194 Support for debugging the Objective-C programming language has been
5195 integrated into GDB.
5197 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5199 DWARF 2's Call Frame Information makes available compiler generated
5200 information that more exactly describes the program's run-time stack.
5201 By using this information, GDB is able to provide more robust stack
5204 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5205 have been updated to use a new backtrace mechanism which includes
5206 DWARF 2 CFI support.
5210 GDB's remote protocol has been extended to include support for hosted
5211 file I/O (where the remote target uses GDB's file system). See GDB's
5212 remote protocol documentation for details.
5214 * All targets using the new architecture framework.
5216 All of GDB's targets have been updated to use the new internal
5217 architecture framework. The way is now open for future GDB releases
5218 to include cross-architecture native debugging support (i386 on amd64,
5221 * GNU/Linux's Thread Local Storage (TLS)
5223 GDB now includes support for for the GNU/Linux implementation of
5224 per-thread variables.
5226 * GNU/Linux's Native POSIX Thread Library (NPTL)
5228 GDB's thread code has been updated to work with either the new
5229 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5231 * Separate debug info.
5233 GDB, in conjunction with BINUTILS, now supports a mechanism for
5234 automatically loading debug information from a separate file. Instead
5235 of shipping full debug and non-debug versions of system libraries,
5236 system integrators can now instead ship just the stripped libraries
5237 and optional debug files.
5239 * DWARF 2 Location Expressions
5241 DWARF 2 Location Expressions allow the compiler to more completely
5242 describe the location of variables (even in optimized code) to the
5245 GDB now includes preliminary support for location expressions (support
5246 for DW_OP_piece is still missing).
5250 A number of long standing bugs that caused GDB to die while starting a
5251 Java application have been fixed. GDB's Java support is now
5252 considered "useable".
5254 * GNU/Linux support for fork, vfork, and exec.
5256 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5257 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5260 * GDB supports logging output to a file
5262 There are two new commands, "set logging" and "show logging", which can be
5263 used to capture GDB's output to a file.
5265 * The meaning of "detach" has changed for gdbserver
5267 The "detach" command will now resume the application, as documented. To
5268 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5271 * d10v, m68hc11 `regs' command deprecated
5273 The `info registers' command has been updated so that it displays the
5274 registers using a format identical to the old `regs' command.
5278 A new command, "maint set profile on/off", has been added. This command can
5279 be used to enable or disable profiling while running GDB, to profile a
5280 session or a set of commands. In addition there is a new configure switch,
5281 "--enable-profiling", which will cause GDB to be compiled with profiling
5282 data, for more informative profiling results.
5284 * Default MI syntax changed to "mi2".
5286 The default MI (machine interface) syntax, enabled by the command line
5287 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5288 "mi1", can be enabled by specifying the option "-i=mi1".
5290 Support for the original "mi0" syntax (included in GDB 5.0) has been
5293 Fix for gdb/192: removed extraneous space when displaying frame level.
5294 Fix for gdb/672: update changelist is now output in mi list format.
5295 Fix for gdb/702: a -var-assign that updates the value now shows up
5296 in a subsequent -var-update.
5298 * New native configurations.
5300 FreeBSD/amd64 x86_64-*-freebsd*
5302 * Multi-arched targets.
5304 HP/PA HPUX11 hppa*-*-hpux*
5305 Renesas M32R/D w/simulator m32r-*-elf*
5307 * OBSOLETE configurations and files
5309 Configurations that have been declared obsolete in this release have
5310 been commented out. Unless there is activity to revive these
5311 configurations, the next release of GDB will have their sources
5312 permanently REMOVED.
5314 Z8000 simulator z8k-zilog-none or z8ksim
5315 Matsushita MN10200 w/simulator mn10200-*-*
5316 H8/500 simulator h8500-hitachi-hms or h8500hms
5317 HP/PA running BSD hppa*-*-bsd*
5318 HP/PA running OSF/1 hppa*-*-osf*
5319 HP/PA Pro target hppa*-*-pro*
5320 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5321 Sequent family i[3456]86-sequent-sysv4*
5322 i[3456]86-sequent-sysv*
5323 i[3456]86-sequent-bsd*
5324 Tsqware Sparclet sparclet-*-*
5325 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5327 * REMOVED configurations and files
5330 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5331 IBM AIX PS/2 i[3456]86-*-aix
5332 i386 running Mach 3.0 i[3456]86-*-mach3*
5333 i386 running Mach i[3456]86-*-mach*
5334 i386 running OSF/1 i[3456]86-*osf1mk*
5335 HP/Apollo 68k Family m68*-apollo*-sysv*,
5337 m68*-hp-bsd*, m68*-hp-hpux*
5338 Argonaut Risc Chip (ARC) arc-*-*
5339 Mitsubishi D30V d30v-*-*
5340 Fujitsu FR30 fr30-*-elf*
5341 OS/9000 i[34]86-*-os9k
5342 I960 with MON960 i960-*-coff
5344 * MIPS $fp behavior changed
5346 The convenience variable $fp, for the MIPS, now consistently returns
5347 the address of the current frame's base. Previously, depending on the
5348 context, $fp could refer to either $sp or the current frame's base
5349 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5350 The GNU Source-Level Debugger''.
5352 *** Changes in GDB 5.3:
5354 * GNU/Linux shared library multi-threaded performance improved.
5356 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5357 `/proc', in preference to `ptrace' for memory reads. This may result
5358 in an improvement in the start-up time of multi-threaded, shared
5359 library applications when run under GDB. One GDB user writes: ``loads
5360 shared libs like mad''.
5362 * ``gdbserver'' now supports multi-threaded applications on some targets
5364 Support for debugging multi-threaded applications which use
5365 the GNU/Linux LinuxThreads package has been added for
5366 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5367 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5369 * GDB now supports C/C++ preprocessor macros.
5371 GDB now expands preprocessor macro invocations in C/C++ expressions,
5372 and provides various commands for showing macro definitions and how
5375 The new command `macro expand EXPRESSION' expands any macro
5376 invocations in expression, and shows the result.
5378 The new command `show macro MACRO-NAME' shows the definition of the
5379 macro named MACRO-NAME, and where it was defined.
5381 Most compilers don't include information about macros in the debugging
5382 information by default. In GCC 3.1, for example, you need to compile
5383 your program with the options `-gdwarf-2 -g3'. If the macro
5384 information is present in the executable, GDB will read it.
5386 * Multi-arched targets.
5388 DEC Alpha (partial) alpha*-*-*
5389 DEC VAX (partial) vax-*-*
5391 National Semiconductor NS32000 (partial) ns32k-*-*
5392 Motorola 68000 (partial) m68k-*-*
5393 Motorola MCORE mcore-*-*
5397 Fujitsu FRV architecture added by Red Hat frv*-*-*
5400 * New native configurations
5402 Alpha NetBSD alpha*-*-netbsd*
5403 SH NetBSD sh*-*-netbsdelf*
5404 MIPS NetBSD mips*-*-netbsd*
5405 UltraSPARC NetBSD sparc64-*-netbsd*
5407 * OBSOLETE configurations and files
5409 Configurations that have been declared obsolete in this release have
5410 been commented out. Unless there is activity to revive these
5411 configurations, the next release of GDB will have their sources
5412 permanently REMOVED.
5414 Mitsubishi D30V d30v-*-*
5415 OS/9000 i[34]86-*-os9k
5416 IBM AIX PS/2 i[3456]86-*-aix
5417 Fujitsu FR30 fr30-*-elf*
5418 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5419 Argonaut Risc Chip (ARC) arc-*-*
5420 i386 running Mach 3.0 i[3456]86-*-mach3*
5421 i386 running Mach i[3456]86-*-mach*
5422 i386 running OSF/1 i[3456]86-*osf1mk*
5423 HP/Apollo 68k Family m68*-apollo*-sysv*,
5425 m68*-hp-bsd*, m68*-hp-hpux*
5426 I960 with MON960 i960-*-coff
5428 * OBSOLETE languages
5430 CHILL, a Pascal like language used by telecommunications companies.
5432 * REMOVED configurations and files
5434 AMD 29k family via UDI a29k-amd-udi, udi29k
5435 A29K VxWorks a29k-*-vxworks
5436 AMD 29000 embedded, using EBMON a29k-none-none
5437 AMD 29000 embedded with COFF a29k-none-coff
5438 AMD 29000 embedded with a.out a29k-none-aout
5440 testsuite/gdb.hp/gdb.threads-hp/ directory
5442 * New command "set max-user-call-depth <nnn>"
5444 This command allows the user to limit the call depth of user-defined
5445 commands. The default is 1024.
5447 * Changes in FreeBSD/i386 native debugging.
5449 Support for the "generate-core-file" has been added.
5451 * New commands "dump", "append", and "restore".
5453 These commands allow data to be copied from target memory
5454 to a bfd-format or binary file (dump and append), and back
5455 from a file into memory (restore).
5457 * Improved "next/step" support on multi-processor Alpha Tru64.
5459 The previous single-step mechanism could cause unpredictable problems,
5460 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5461 of a software single-step mechanism prevents this.
5463 *** Changes in GDB 5.2.1:
5471 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5472 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5473 Fix, by Joel Brobecker imported from mainline.
5475 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5476 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5477 Fix, by Fred Fish, imported from mainline.
5479 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5480 Surprisingly enough, it works now.
5481 By Michal Ludvig, imported from mainline.
5483 i386 hardware watchpoint support:
5484 avoid misses on second run for some targets.
5485 By Pierre Muller, imported from mainline.
5487 *** Changes in GDB 5.2:
5489 * New command "set trust-readonly-sections on[off]".
5491 This command is a hint that tells gdb that read-only sections
5492 really are read-only (ie. that their contents will not change).
5493 In this mode, gdb will go to the object file rather than the
5494 target to read memory from read-only sections (such as ".text").
5495 This can be a significant performance improvement on some
5496 (notably embedded) targets.
5498 * New command "generate-core-file" (or "gcore").
5500 This new gdb command allows the user to drop a core file of the child
5501 process state at any time. So far it's been implemented only for
5502 GNU/Linux and Solaris, but should be relatively easily ported to other
5503 hosts. Argument is core file name (defaults to core.<pid>).
5505 * New command line option
5507 GDB now accepts --pid or -p followed by a process id.
5509 * Change in command line behavior -- corefiles vs. process ids.
5511 There is a subtle behavior in the way in which GDB handles
5512 command line arguments. The first non-flag argument is always
5513 a program to debug, but the second non-flag argument may either
5514 be a corefile or a process id. Previously, GDB would attempt to
5515 open the second argument as a corefile, and if that failed, would
5516 issue a superfluous error message and then attempt to attach it as
5517 a process. Now, if the second argument begins with a non-digit,
5518 it will be treated as a corefile. If it begins with a digit,
5519 GDB will attempt to attach it as a process, and if no such process
5520 is found, will then attempt to open it as a corefile.
5522 * Changes in ARM configurations.
5524 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5525 configuration is fully multi-arch.
5527 * New native configurations
5529 ARM NetBSD arm*-*-netbsd*
5530 x86 OpenBSD i[3456]86-*-openbsd*
5531 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5532 Sparc64 running FreeBSD sparc64-*-freebsd*
5536 Sanyo XStormy16 xstormy16-elf
5538 * OBSOLETE configurations and files
5540 Configurations that have been declared obsolete in this release have
5541 been commented out. Unless there is activity to revive these
5542 configurations, the next release of GDB will have their sources
5543 permanently REMOVED.
5545 AMD 29k family via UDI a29k-amd-udi, udi29k
5546 A29K VxWorks a29k-*-vxworks
5547 AMD 29000 embedded, using EBMON a29k-none-none
5548 AMD 29000 embedded with COFF a29k-none-coff
5549 AMD 29000 embedded with a.out a29k-none-aout
5551 testsuite/gdb.hp/gdb.threads-hp/ directory
5553 * REMOVED configurations and files
5555 TI TMS320C80 tic80-*-*
5557 PowerPC Solaris powerpcle-*-solaris*
5558 PowerPC Windows NT powerpcle-*-cygwin32
5559 PowerPC Netware powerpc-*-netware*
5560 Harris/CXUX m88k m88*-harris-cxux*
5561 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5562 ns32k-utek-sysv* ns32k-utek-*
5563 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5564 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5565 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5566 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5567 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5569 * Changes to command line processing
5571 The new `--args' feature can be used to specify command-line arguments
5572 for the inferior from gdb's command line.
5574 * Changes to key bindings
5576 There is a new `operate-and-get-next' function bound to `C-o'.
5578 *** Changes in GDB 5.1.1
5580 Fix compile problem on DJGPP.
5582 Fix a problem with floating-point registers on the i386 being
5585 Fix to stop GDB crashing on .debug_str debug info.
5587 Numerous documentation fixes.
5589 Numerous testsuite fixes.
5591 *** Changes in GDB 5.1:
5593 * New native configurations
5595 Alpha FreeBSD alpha*-*-freebsd*
5596 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5597 MIPS GNU/Linux mips*-*-linux*
5598 MIPS SGI Irix 6.x mips*-sgi-irix6*
5599 ia64 AIX ia64-*-aix*
5600 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5604 Motorola 68HC11 and 68HC12 m68hc11-elf
5606 UltraSparc running GNU/Linux sparc64-*-linux*
5608 * OBSOLETE configurations and files
5610 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5611 Harris/CXUX m88k m88*-harris-cxux*
5612 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5613 ns32k-utek-sysv* ns32k-utek-*
5614 TI TMS320C80 tic80-*-*
5616 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5617 PowerPC Solaris powerpcle-*-solaris*
5618 PowerPC Windows NT powerpcle-*-cygwin32
5619 PowerPC Netware powerpc-*-netware*
5620 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5621 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5622 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5623 Apple Macintosh (MPW) host N/A
5625 stuff.c (Program to stuff files into a specially prepared space in kdb)
5626 kdb-start.c (Main loop for the standalone kernel debugger)
5628 Configurations that have been declared obsolete in this release have
5629 been commented out. Unless there is activity to revive these
5630 configurations, the next release of GDB will have their sources
5631 permanently REMOVED.
5633 * REMOVED configurations and files
5635 Altos 3068 m68*-altos-*
5636 Convex c1-*-*, c2-*-*
5638 ARM RISCix arm-*-* (as host)
5642 * GDB has been converted to ISO C.
5644 GDB's source code has been converted to ISO C. In particular, the
5645 sources are fully protoized, and rely on standard headers being
5650 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5652 * The MI enabled by default.
5654 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5655 revised and enabled by default. Packages which use GDB as a debugging
5656 engine behind a UI or another front end are encouraged to switch to
5657 using the GDB/MI interface, instead of the old annotations interface
5658 which is now deprecated.
5660 * Support for debugging Pascal programs.
5662 GDB now includes support for debugging Pascal programs. The following
5663 main features are supported:
5665 - Pascal-specific data types such as sets;
5667 - automatic recognition of Pascal sources based on file-name
5670 - Pascal-style display of data types, variables, and functions;
5672 - a Pascal expression parser.
5674 However, some important features are not yet supported.
5676 - Pascal string operations are not supported at all;
5678 - there are some problems with boolean types;
5680 - Pascal type hexadecimal constants are not supported
5681 because they conflict with the internal variables format;
5683 - support for Pascal objects and classes is not full yet;
5685 - unlike Pascal, GDB is case-sensitive for symbol names.
5687 * Changes in completion.
5689 Commands such as `shell', `run' and `set args', which pass arguments
5690 to inferior programs, now complete on file names, similar to what
5691 users expect at the shell prompt.
5693 Commands which accept locations, such as `disassemble', `print',
5694 `breakpoint', `until', etc. now complete on filenames as well as
5695 program symbols. Thus, if you type "break foob TAB", and the source
5696 files linked into the programs include `foobar.c', that file name will
5697 be one of the candidates for completion. However, file names are not
5698 considered for completion after you typed a colon that delimits a file
5699 name from a name of a function in that file, as in "break foo.c:bar".
5701 `set demangle-style' completes on available demangling styles.
5703 * New platform-independent commands:
5705 It is now possible to define a post-hook for a command as well as a
5706 hook that runs before the command. For more details, see the
5707 documentation of `hookpost' in the GDB manual.
5709 * Changes in GNU/Linux native debugging.
5711 Support for debugging multi-threaded programs has been completely
5712 revised for all platforms except m68k and sparc. You can now debug as
5713 many threads as your system allows you to have.
5715 Attach/detach is supported for multi-threaded programs.
5717 Support for SSE registers was added for x86. This doesn't work for
5718 multi-threaded programs though.
5720 * Changes in MIPS configurations.
5722 Multi-arch support is enabled for all MIPS configurations.
5724 GDB can now be built as native debugger on SGI Irix 6.x systems for
5725 debugging n32 executables. (Debugging 64-bit executables is not yet
5728 * Unified support for hardware watchpoints in all x86 configurations.
5730 Most (if not all) native x86 configurations support hardware-assisted
5731 breakpoints and watchpoints in a unified manner. This support
5732 implements debug register sharing between watchpoints, which allows to
5733 put a virtually infinite number of watchpoints on the same address,
5734 and also supports watching regions up to 16 bytes with several debug
5737 The new maintenance command `maintenance show-debug-regs' toggles
5738 debugging print-outs in functions that insert, remove, and test
5739 watchpoints and hardware breakpoints.
5741 * Changes in the DJGPP native configuration.
5743 New command ``info dos sysinfo'' displays assorted information about
5744 the CPU, OS, memory, and DPMI server.
5746 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5747 display information about segment descriptors stored in GDT, LDT, and
5750 New commands ``info dos pde'' and ``info dos pte'' display entries
5751 from Page Directory and Page Tables (for now works with CWSDPMI only).
5752 New command ``info dos address-pte'' displays the Page Table entry for
5753 a given linear address.
5755 GDB can now pass command lines longer than 126 characters to the
5756 program being debugged (requires an update to the libdbg.a library
5757 which is part of the DJGPP development kit).
5759 DWARF2 debug info is now supported.
5761 It is now possible to `step' and `next' through calls to `longjmp'.
5763 * Changes in documentation.
5765 All GDB documentation was converted to GFDL, the GNU Free
5766 Documentation License.
5768 Tracepoints-related commands are now fully documented in the GDB
5771 TUI, the Text-mode User Interface, is now documented in the manual.
5773 Tracepoints-related commands are now fully documented in the GDB
5776 The "GDB Internals" manual now has an index. It also includes
5777 documentation of `ui_out' functions, GDB coding standards, x86
5778 hardware watchpoints, and memory region attributes.
5780 * GDB's version number moved to ``version.in''
5782 The Makefile variable VERSION has been replaced by the file
5783 ``version.in''. People creating GDB distributions should update the
5784 contents of this file.
5788 GUD support is now a standard part of the EMACS distribution.
5790 *** Changes in GDB 5.0:
5792 * Improved support for debugging FP programs on x86 targets
5794 Unified and much-improved support for debugging floating-point
5795 programs on all x86 targets. In particular, ``info float'' now
5796 displays the FP registers in the same format on all x86 targets, with
5797 greater level of detail.
5799 * Improvements and bugfixes in hardware-assisted watchpoints
5801 It is now possible to watch array elements, struct members, and
5802 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5803 on x86 targets no longer erroneously trigger when the address is
5806 * Improvements in the native DJGPP version of GDB
5808 The distribution now includes all the scripts and auxiliary files
5809 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5810 machines ``out of the box''.
5812 The DJGPP version can now debug programs that use signals. It is
5813 possible to catch signals that happened in the debuggee, deliver
5814 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5815 would kill the program being debugged.) Programs that hook hardware
5816 interrupts (keyboard, timer, etc.) can also be debugged.
5818 It is now possible to debug DJGPP programs that redirect their
5819 standard handles or switch them to raw (as opposed to cooked) mode, or
5820 even close them. The command ``run < foo > bar'' works as expected,
5821 and ``info terminal'' reports useful information about the debuggee's
5822 terminal, including raw/cooked mode, redirection, etc.
5824 The DJGPP version now uses termios functions for console I/O, which
5825 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5828 DOS-style file names with drive letters are now fully supported by
5831 It is now possible to debug DJGPP programs that switch their working
5832 directory. It is also possible to rerun the debuggee any number of
5833 times without restarting GDB; thus, you can use the same setup,
5834 breakpoints, etc. for many debugging sessions.
5836 * New native configurations
5838 ARM GNU/Linux arm*-*-linux*
5839 PowerPC GNU/Linux powerpc-*-linux*
5843 Motorola MCore mcore-*-*
5844 x86 VxWorks i[3456]86-*-vxworks*
5845 PowerPC VxWorks powerpc-*-vxworks*
5846 TI TMS320C80 tic80-*-*
5848 * OBSOLETE configurations
5850 Altos 3068 m68*-altos-*
5851 Convex c1-*-*, c2-*-*
5853 ARM RISCix arm-*-* (as host)
5856 Configurations that have been declared obsolete will be commented out,
5857 but the code will be left in place. If there is no activity to revive
5858 these configurations before the next release of GDB, the sources will
5859 be permanently REMOVED.
5861 * Gould support removed
5863 Support for the Gould PowerNode and NP1 has been removed.
5865 * New features for SVR4
5867 On SVR4 native platforms (such as Solaris), if you attach to a process
5868 without first loading a symbol file, GDB will now attempt to locate and
5869 load symbols from the running process's executable file.
5871 * Many C++ enhancements
5873 C++ support has been greatly improved. Overload resolution now works properly
5874 in almost all cases. RTTI support is on the way.
5876 * Remote targets can connect to a sub-program
5878 A popen(3) style serial-device has been added. This device starts a
5879 sub-process (such as a stand-alone simulator) and then communicates
5880 with that. The sub-program to run is specified using the syntax
5881 ``|<program> <args>'' vis:
5883 (gdb) set remotedebug 1
5884 (gdb) target extended-remote |mn10300-elf-sim program-args
5886 * MIPS 64 remote protocol
5888 A long standing bug in the mips64 remote protocol where by GDB
5889 expected certain 32 bit registers (ex SR) to be transfered as 32
5890 instead of 64 bits has been fixed.
5892 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5893 added to provide backward compatibility with older versions of GDB.
5895 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5897 The command ``set remotebinarydownload'' command has been replaced by
5898 ``set remote X-packet''. Other commands in ``set remote'' family
5899 include ``set remote P-packet''.
5901 * Breakpoint commands accept ranges.
5903 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5904 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5905 ``tracepoint passcount'' also accepts a range of tracepoints.
5907 * ``apropos'' command added.
5909 The ``apropos'' command searches through command names and
5910 documentation strings, printing out matches, making it much easier to
5911 try to find a command that does what you are looking for.
5915 A new machine oriented interface (MI) has been added to GDB. This
5916 interface is designed for debug environments running GDB as a separate
5917 process. This is part of the long term libGDB project. See the
5918 "GDB/MI" chapter of the GDB manual for further information. It can be
5919 enabled by configuring with:
5921 .../configure --enable-gdbmi
5923 *** Changes in GDB-4.18:
5925 * New native configurations
5927 HP-UX 10.20 hppa*-*-hpux10.20
5928 HP-UX 11.x hppa*-*-hpux11.0*
5929 M68K GNU/Linux m68*-*-linux*
5933 Fujitsu FR30 fr30-*-elf*
5934 Intel StrongARM strongarm-*-*
5935 Mitsubishi D30V d30v-*-*
5937 * OBSOLETE configurations
5939 Gould PowerNode, NP1 np1-*-*, pn-*-*
5941 Configurations that have been declared obsolete will be commented out,
5942 but the code will be left in place. If there is no activity to revive
5943 these configurations before the next release of GDB, the sources will
5944 be permanently REMOVED.
5948 As a compatibility experiment, GDB's source files buildsym.h and
5949 buildsym.c have been converted to pure standard C, no longer
5950 containing any K&R compatibility code. We believe that all systems in
5951 use today either come with a standard C compiler, or have a GCC port
5952 available. If this is not true, please report the affected
5953 configuration to bug-gdb@gnu.org immediately. See the README file for
5954 information about getting a standard C compiler if you don't have one
5959 GDB now uses readline 2.2.
5961 * set extension-language
5963 You can now control the mapping between filename extensions and source
5964 languages by using the `set extension-language' command. For instance,
5965 you can ask GDB to treat .c files as C++ by saying
5966 set extension-language .c c++
5967 The command `info extensions' lists all of the recognized extensions
5968 and their associated languages.
5970 * Setting processor type for PowerPC and RS/6000
5972 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5973 you can use the `set processor' command to specify what variant of the
5974 PowerPC family you are debugging. The command
5978 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5979 following PowerPC and RS6000 variants:
5981 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5982 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5984 403GC IBM PowerPC 403GC
5985 505 Motorola PowerPC 505
5986 860 Motorola PowerPC 860 or 850
5987 601 Motorola PowerPC 601
5988 602 Motorola PowerPC 602
5989 603 Motorola/IBM PowerPC 603 or 603e
5990 604 Motorola PowerPC 604 or 604e
5991 750 Motorola/IBM PowerPC 750 or 750
5993 At the moment, this command just tells GDB what to name the
5994 special-purpose processor registers. Since almost all the affected
5995 registers are inaccessible to user-level programs, this command is
5996 only useful for remote debugging in its present form.
6000 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6001 more extensive support for HP-UX. Added features include shared
6002 library support, kernel threads and hardware watchpoints for 11.00,
6003 support for HP's ANSI C and C++ compilers, and a compatibility mode
6004 for xdb and dbx commands.
6008 HP's donation includes the new concept of catchpoints, which is a
6009 generalization of the old catch command. On HP-UX, it is now possible
6010 to catch exec, fork, and vfork, as well as library loading.
6012 This means that the existing catch command has changed; its first
6013 argument now specifies the type of catch to be set up. See the
6014 output of "help catch" for a list of catchpoint types.
6016 * Debugging across forks
6018 On HP-UX, you can choose which process to debug when a fork() happens
6023 HP has donated a curses-based terminal user interface (TUI). To get
6024 it, build with --enable-tui. Although this can be enabled for any
6025 configuration, at present it only works for native HP debugging.
6027 * GDB remote protocol additions
6029 A new protocol packet 'X' that writes binary data is now available.
6030 Default behavior is to try 'X', then drop back to 'M' if the stub
6031 fails to respond. The settable variable `remotebinarydownload'
6032 allows explicit control over the use of 'X'.
6034 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6035 full 64-bit address. The command
6037 set remoteaddresssize 32
6039 can be used to revert to the old behaviour. For existing remote stubs
6040 the change should not be noticed, as the additional address information
6043 In order to assist in debugging stubs, you may use the maintenance
6044 command `packet' to send any text string to the stub. For instance,
6046 maint packet heythere
6048 sends the packet "$heythere#<checksum>". Note that it is very easy to
6049 disrupt a debugging session by sending the wrong packet at the wrong
6052 The compare-sections command allows you to compare section data on the
6053 target to what is in the executable file without uploading or
6054 downloading, by comparing CRC checksums.
6056 * Tracing can collect general expressions
6058 You may now collect general expressions at tracepoints. This requires
6059 further additions to the target-side stub; see tracepoint.c and
6060 doc/agentexpr.texi for further details.
6062 * mask-address variable for Mips
6064 For Mips targets, you may control the zeroing of the upper 32 bits of
6065 a 64-bit address by entering `set mask-address on'. This is mainly
6066 of interest to users of embedded R4xxx and R5xxx processors.
6068 * Higher serial baud rates
6070 GDB's serial code now allows you to specify baud rates 57600, 115200,
6071 230400, and 460800 baud. (Note that your host system may not be able
6072 to achieve all of these rates.)
6076 The i960 configuration now includes an initial implementation of a
6077 builtin simulator, contributed by Jim Wilson.
6080 *** Changes in GDB-4.17:
6082 * New native configurations
6084 Alpha GNU/Linux alpha*-*-linux*
6085 Unixware 2.x i[3456]86-unixware2*
6086 Irix 6.x mips*-sgi-irix6*
6087 PowerPC GNU/Linux powerpc-*-linux*
6088 PowerPC Solaris powerpcle-*-solaris*
6089 Sparc GNU/Linux sparc-*-linux*
6090 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6094 Argonaut Risc Chip (ARC) arc-*-*
6095 Hitachi H8/300S h8300*-*-*
6096 Matsushita MN10200 w/simulator mn10200-*-*
6097 Matsushita MN10300 w/simulator mn10300-*-*
6098 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6099 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6100 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6101 Mitsubishi D10V w/simulator d10v-*-*
6102 Mitsubishi M32R/D w/simulator m32r-*-elf*
6103 Tsqware Sparclet sparclet-*-*
6104 NEC V850 w/simulator v850-*-*
6106 * New debugging protocols
6108 ARM with RDI protocol arm*-*-*
6109 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6110 DDB and LSI variants of PMON protocol mips*-*-*
6111 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6112 PowerPC with SDS protocol powerpc{,le}-*-eabi
6113 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6117 All configurations can now understand and use the DWARF 2 debugging
6118 format. The choice is automatic, if the symbol file contains DWARF 2
6123 GDB now includes basic Java language support. This support is
6124 only useful with Java compilers that produce native machine code.
6126 * solib-absolute-prefix and solib-search-path
6128 For SunOS and SVR4 shared libraries, you may now set the prefix for
6129 loading absolute shared library symbol files, and the search path for
6130 locating non-absolute shared library symbol files.
6132 * Live range splitting
6134 GDB can now effectively debug code for which GCC has performed live
6135 range splitting as part of its optimization. See gdb/doc/LRS for
6136 more details on the expected format of the stabs information.
6140 GDB's support for the GNU Hurd, including thread debugging, has been
6141 updated to work with current versions of the Hurd.
6145 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6146 instruction set. ARM GDB automatically detects when Thumb
6147 instructions are in use, and adjusts disassembly and backtracing
6152 GDB's MIPS target configurations now handle the MIP16 16-bit
6157 GDB now includes support for overlays; if an executable has been
6158 linked such that multiple sections are based at the same address, GDB
6159 will decide which section to use for symbolic info. You can choose to
6160 control the decision manually, using overlay commands, or implement
6161 additional target-side support and use "overlay load-target" to bring
6162 in the overlay mapping. Do "help overlay" for more detail.
6166 The command "info symbol <address>" displays information about
6167 the symbol at the specified address.
6171 The standard remote protocol now includes an extension that allows
6172 asynchronous collection and display of trace data. This requires
6173 extensive support in the target-side debugging stub. Tracing mode
6174 includes a new interaction mode in GDB and new commands: see the
6175 file tracepoint.c for more details.
6179 Configurations for embedded MIPS now include a simulator contributed
6180 by Cygnus Solutions. The simulator supports the instruction sets
6181 of most MIPS variants.
6185 Sparc configurations may now include the ERC32 simulator contributed
6186 by the European Space Agency. The simulator is not built into
6187 Sparc targets by default; configure with --enable-sim to include it.
6191 For target configurations that may include multiple variants of a
6192 basic architecture (such as MIPS and SH), you may now set the
6193 architecture explicitly. "set arch" sets, "info arch" lists
6194 the possible architectures.
6196 *** Changes in GDB-4.16:
6198 * New native configurations
6200 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6201 M68K NetBSD m68k-*-netbsd*
6202 PowerPC AIX 4.x powerpc-*-aix*
6203 PowerPC MacOS powerpc-*-macos*
6204 PowerPC Windows NT powerpcle-*-cygwin32
6205 RS/6000 AIX 4.x rs6000-*-aix4*
6209 ARM with RDP protocol arm-*-*
6210 I960 with MON960 i960-*-coff
6211 MIPS VxWorks mips*-*-vxworks*
6212 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6213 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6215 Matra Sparclet sparclet-*-*
6219 The powerpc-eabi configuration now includes the PSIM simulator,
6220 contributed by Andrew Cagney, with assistance from Mike Meissner.
6221 PSIM is a very elaborate model of the PowerPC, including not only
6222 basic instruction set execution, but also details of execution unit
6223 performance and I/O hardware. See sim/ppc/README for more details.
6227 GDB now works with Solaris 2.5.
6229 * Windows 95/NT native
6231 GDB will now work as a native debugger on Windows 95 and Windows NT.
6232 To build it from source, you must use the "gnu-win32" environment,
6233 which uses a DLL to emulate enough of Unix to run the GNU tools.
6234 Further information, binaries, and sources are available at
6235 ftp.cygnus.com, under pub/gnu-win32.
6237 * dont-repeat command
6239 If a user-defined command includes the command `dont-repeat', then the
6240 command will not be repeated if the user just types return. This is
6241 useful if the command is time-consuming to run, so that accidental
6242 extra keystrokes don't run the same command many times.
6244 * Send break instead of ^C
6246 The standard remote protocol now includes an option to send a break
6247 rather than a ^C to the target in order to interrupt it. By default,
6248 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6250 * Remote protocol timeout
6252 The standard remote protocol includes a new variable `remotetimeout'
6253 that allows you to set the number of seconds before GDB gives up trying
6254 to read from the target. The default value is 2.
6256 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6258 By default GDB will automatically keep track of objects as they are
6259 loaded and unloaded by the dynamic linker. By using the command `set
6260 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6261 when shared library events occur, thus allowing you to set breakpoints
6262 in shared libraries which are explicitly loaded by the inferior.
6264 Note this feature does not work on hpux8. On hpux9 you must link
6265 /usr/lib/end.o into your program. This feature should work
6266 automatically on hpux10.
6268 * Irix 5.x hardware watchpoint support
6270 Irix 5 configurations now support the use of hardware watchpoints.
6272 * Mips protocol "SYN garbage limit"
6274 When debugging a Mips target using the `target mips' protocol, you
6275 may set the number of characters that GDB will ignore by setting
6276 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6277 every character. The default value is 1050.
6279 * Recording and replaying remote debug sessions
6281 If you set `remotelogfile' to the name of a file, gdb will write to it
6282 a recording of a remote debug session. This recording may then be
6283 replayed back to gdb using "gdbreplay". See gdbserver/README for
6284 details. This is useful when you have a problem with GDB while doing
6285 remote debugging; you can make a recording of the session and send it
6286 to someone else, who can then recreate the problem.
6288 * Speedups for remote debugging
6290 GDB includes speedups for downloading and stepping MIPS systems using
6291 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6292 and more efficient S-record downloading.
6294 * Memory use reductions and statistics collection
6296 GDB now uses less memory and reports statistics about memory usage.
6297 Try the `maint print statistics' command, for example.
6299 *** Changes in GDB-4.15:
6301 * Psymtabs for XCOFF
6303 The symbol reader for AIX GDB now uses partial symbol tables. This
6304 can greatly improve startup time, especially for large executables.
6306 * Remote targets use caching
6308 Remote targets now use a data cache to speed up communication with the
6309 remote side. The data cache could lead to incorrect results because
6310 it doesn't know about volatile variables, thus making it impossible to
6311 debug targets which use memory mapped I/O devices. `set remotecache
6312 off' turns the the data cache off.
6314 * Remote targets may have threads
6316 The standard remote protocol now includes support for multiple threads
6317 in the target system, using new protocol commands 'H' and 'T'. See
6318 gdb/remote.c for details.
6322 If GDB is configured with `--enable-netrom', then it will include
6323 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6324 acts as though it is a bank of ROM on the target board, but you can
6325 write into it over the network. GDB's support consists only of
6326 support for fast loading into the emulated ROM; to debug, you must use
6327 another protocol, such as standard remote protocol. The usual
6328 sequence is something like
6330 target nrom <netrom-hostname>
6332 target remote <netrom-hostname>:1235
6336 GDB now includes support for the Apple Macintosh, as a host only. It
6337 may be run as either an MPW tool or as a standalone application, and
6338 it can debug through the serial port. All the usual GDB commands are
6339 available, but to the target command, you must supply "serial" as the
6340 device type instead of "/dev/ttyXX". See mpw-README in the main
6341 directory for more information on how to build. The MPW configuration
6342 scripts */mpw-config.in support only a few targets, and only the
6343 mips-idt-ecoff target has been tested.
6347 GDB configuration now uses autoconf. This is not user-visible,
6348 but does simplify configuration and building.
6352 GDB now supports hpux10.
6354 *** Changes in GDB-4.14:
6356 * New native configurations
6358 x86 FreeBSD i[345]86-*-freebsd
6359 x86 NetBSD i[345]86-*-netbsd
6360 NS32k NetBSD ns32k-*-netbsd
6361 Sparc NetBSD sparc-*-netbsd
6365 A29K VxWorks a29k-*-vxworks
6366 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6367 CPU32 EST-300 emulator m68*-*-est*
6368 PowerPC ELF powerpc-*-elf
6371 * Alpha OSF/1 support for procfs
6373 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6374 possible to attach to running processes. As the mounting of the /proc
6375 filesystem is optional on the Alpha, GDB automatically determines
6376 the availability of /proc during startup. This can lead to problems
6377 if /proc is unmounted after GDB has been started.
6379 * Arguments to user-defined commands
6381 User commands may accept up to 10 arguments separated by whitespace.
6382 Arguments are accessed within the user command via $arg0..$arg9. A
6385 print $arg0 + $arg1 + $arg2
6387 To execute the command use:
6390 Defines the command "adder" which prints the sum of its three arguments.
6391 Note the arguments are text substitutions, so they may reference variables,
6392 use complex expressions, or even perform inferior function calls.
6394 * New `if' and `while' commands
6396 This makes it possible to write more sophisticated user-defined
6397 commands. Both commands take a single argument, which is the
6398 expression to evaluate, and must be followed by the commands to
6399 execute, one per line, if the expression is nonzero, the list being
6400 terminated by the word `end'. The `if' command list may include an
6401 `else' word, which causes the following commands to be executed only
6402 if the expression is zero.
6404 * Fortran source language mode
6406 GDB now includes partial support for Fortran 77. It will recognize
6407 Fortran programs and can evaluate a subset of Fortran expressions, but
6408 variables and functions may not be handled correctly. GDB will work
6409 with G77, but does not yet know much about symbols emitted by other
6412 * Better HPUX support
6414 Most debugging facilities now work on dynamic executables for HPPAs
6415 running hpux9 or later. You can attach to running dynamically linked
6416 processes, but by default the dynamic libraries will be read-only, so
6417 for instance you won't be able to put breakpoints in them. To change
6418 that behavior do the following before running the program:
6424 This will cause the libraries to be mapped private and read-write.
6425 To revert to the normal behavior, do this:
6431 You cannot set breakpoints or examine data in the library until after
6432 the library is loaded if the function/data symbols do not have
6435 GDB can now also read debug symbols produced by the HP C compiler on
6436 HPPAs (sorry, no C++, Fortran or 68k support).
6438 * Target byte order now dynamically selectable
6440 You can choose which byte order to use with a target system, via the
6441 commands "set endian big" and "set endian little", and you can see the
6442 current setting by using "show endian". You can also give the command
6443 "set endian auto", in which case GDB will use the byte order
6444 associated with the executable. Currently, only embedded MIPS
6445 configurations support dynamic selection of target byte order.
6447 * New DOS host serial code
6449 This version uses DPMI interrupts to handle buffered I/O, so you
6450 no longer need to run asynctsr when debugging boards connected to
6453 *** Changes in GDB-4.13:
6455 * New "complete" command
6457 This lists all the possible completions for the rest of the line, if it
6458 were to be given as a command itself. This is intended for use by emacs.
6460 * Trailing space optional in prompt
6462 "set prompt" no longer adds a space for you after the prompt you set. This
6463 allows you to set a prompt which ends in a space or one that does not.
6465 * Breakpoint hit counts
6467 "info break" now displays a count of the number of times the breakpoint
6468 has been hit. This is especially useful in conjunction with "ignore"; you
6469 can ignore a large number of breakpoint hits, look at the breakpoint info
6470 to see how many times the breakpoint was hit, then run again, ignoring one
6471 less than that number, and this will get you quickly to the last hit of
6474 * Ability to stop printing at NULL character
6476 "set print null-stop" will cause GDB to stop printing the characters of
6477 an array when the first NULL is encountered. This is useful when large
6478 arrays actually contain only short strings.
6480 * Shared library breakpoints
6482 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6483 breakpoints in shared libraries before the executable is run.
6485 * Hardware watchpoints
6487 There is a new hardware breakpoint for the watch command for sparclite
6488 targets. See gdb/sparclite/hw_breakpoint.note.
6490 Hardware watchpoints are also now supported under GNU/Linux.
6494 Annotations have been added. These are for use with graphical interfaces,
6495 and are still experimental. Currently only gdba.el uses these.
6497 * Improved Irix 5 support
6499 GDB now works properly with Irix 5.2.
6501 * Improved HPPA support
6503 GDB now works properly with the latest GCC and GAS.
6505 * New native configurations
6507 Sequent PTX4 i[34]86-sequent-ptx4
6508 HPPA running OSF/1 hppa*-*-osf*
6509 Atari TT running SVR4 m68*-*-sysv4*
6510 RS/6000 LynxOS rs6000-*-lynxos*
6514 OS/9000 i[34]86-*-os9k
6515 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6518 * Hitachi SH7000 and E7000-PC ICE support
6520 There is now support for communicating with the Hitachi E7000-PC ICE.
6521 This is available automatically when GDB is configured for the SH.
6525 As usual, a variety of small fixes and improvements, both generic
6526 and configuration-specific. See the ChangeLog for more detail.
6528 *** Changes in GDB-4.12:
6530 * Irix 5 is now supported
6534 GDB-4.12 on the HPPA has a number of changes which make it unable
6535 to debug the output from the currently released versions of GCC and
6536 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6537 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6538 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6541 *** Changes in GDB-4.11:
6543 * User visible changes:
6547 The "set remotedebug" option is now consistent between the mips remote
6548 target, remote targets using the gdb-specific protocol, UDI (AMD's
6549 debug protocol for the 29k) and the 88k bug monitor. It is now an
6550 integer specifying a debug level (normally 0 or 1, but 2 means more
6551 debugging info for the mips target).
6553 * DEC Alpha native support
6555 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6556 debug info, but GDB works fairly well with the DEC compiler and should
6557 work with a future GCC release. See the README file for a few
6558 Alpha-specific notes.
6560 * Preliminary thread implementation
6562 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6564 * LynxOS native and target support for 386
6566 This release has been hosted on LynxOS 2.2, and also can be configured
6567 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6570 * Improvements in C++ mangling/demangling.
6572 This release has much better g++ debugging, specifically in name
6573 mangling/demangling, virtual function calls, print virtual table,
6574 call methods, ...etc.
6576 *** Changes in GDB-4.10:
6578 * User visible changes:
6580 Remote debugging using the GDB-specific (`target remote') protocol now
6581 supports the `load' command. This is only useful if you have some
6582 other way of getting the stub to the target system, and you can put it
6583 somewhere in memory where it won't get clobbered by the download.
6585 Filename completion now works.
6587 When run under emacs mode, the "info line" command now causes the
6588 arrow to point to the line specified. Also, "info line" prints
6589 addresses in symbolic form (as well as hex).
6591 All vxworks based targets now support a user settable option, called
6592 vxworks-timeout. This option represents the number of seconds gdb
6593 should wait for responses to rpc's. You might want to use this if
6594 your vxworks target is, perhaps, a slow software simulator or happens
6595 to be on the far side of a thin network line.
6599 This release contains support for using a DEC alpha as a GDB host for
6600 cross debugging. Native alpha debugging is not supported yet.
6603 *** Changes in GDB-4.9:
6607 This is the first GDB release which is accompanied by a matching testsuite.
6608 The testsuite requires installation of dejagnu, which should be available
6609 via ftp from most sites that carry GNU software.
6613 'Cfront' style demangling has had its name changed to 'ARM' style, to
6614 emphasize that it was written from the specifications in the C++ Annotated
6615 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6616 disclaimers, it still generated too much confusion with users attempting to
6617 use gdb with AT&T cfront.
6621 GDB now uses a standard remote interface to a simulator library.
6622 So far, the library contains simulators for the Zilog Z8001/2, the
6623 Hitachi H8/300, H8/500 and Super-H.
6625 * New targets supported
6627 H8/300 simulator h8300-hitachi-hms or h8300hms
6628 H8/500 simulator h8500-hitachi-hms or h8500hms
6629 SH simulator sh-hitachi-hms or sh
6630 Z8000 simulator z8k-zilog-none or z8ksim
6631 IDT MIPS board over serial line mips-idt-ecoff
6633 Cross-debugging to GO32 targets is supported. It requires a custom
6634 version of the i386-stub.c module which is integrated with the
6635 GO32 memory extender.
6637 * New remote protocols
6639 MIPS remote debugging protocol.
6641 * New source languages supported
6643 This version includes preliminary support for Chill, a Pascal like language
6644 used by telecommunications companies. Chill support is also being integrated
6645 into the GNU compiler, but we don't know when it will be publically available.
6648 *** Changes in GDB-4.8:
6650 * HP Precision Architecture supported
6652 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6653 version of this support was available as a set of patches from the
6654 University of Utah. GDB does not support debugging of programs
6655 compiled with the HP compiler, because HP will not document their file
6656 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6657 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6659 Many problems in the preliminary version have been fixed.
6661 * Faster and better demangling
6663 We have improved template demangling and fixed numerous bugs in the GNU style
6664 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6665 character types (wchar_t) are now supported. Demangling of each symbol is now
6666 only done once, and is cached when the symbol table for a file is read in.
6667 This results in a small increase in memory usage for C programs, a moderate
6668 increase in memory usage for C++ programs, and a fantastic speedup in
6671 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6672 from the specifications in the Annotated Reference Manual, which AT&T's
6673 compiler does not actually implement.
6675 * G++ multiple inheritance compiler problem
6677 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6678 inheritance lattices was reworked to properly discover ambiguities. We
6679 recently found an example which causes this new algorithm to fail in a
6680 very subtle way, producing bad debug information for those classes.
6681 The file 'gcc.patch' (in this directory) can be applied to gcc to
6682 circumvent the problem. A future GCC release will contain a complete
6685 The previous G++ debug info problem (mentioned below for the gdb-4.7
6686 release) is fixed in gcc version 2.3.2.
6688 * Improved configure script
6690 The `configure' script will now attempt to guess your system type if
6691 you don't supply a host system type. The old scheme of supplying a
6692 host system triplet is preferable over using this. All the magic is
6693 done in the new `config.guess' script. Examine it for details.
6695 We have also brought our configure script much more in line with the FSF's
6696 version. It now supports the --with-xxx options. In particular,
6697 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6698 The resulting GDB will not be able to read arbitrary object file formats --
6699 only the format ``expected'' to be used on the configured target system.
6700 We hope to make this the default in a future release.
6702 * Documentation improvements
6704 There's new internal documentation on how to modify GDB, and how to
6705 produce clean changes to the code. We implore people to read it
6706 before submitting changes.
6708 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6709 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6710 `info' files are also provided. To build `info' files from scratch,
6711 you will need the latest `makeinfo' release, which will be available in
6712 a future texinfo-X.Y release.
6714 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6715 We're not sure exactly which versions have this problem, but it has
6716 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6717 or better. If that isn't possible, there is a patch in
6718 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6719 around this problem.
6723 GDB now supports array constants that can be used in expressions typed in by
6724 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6725 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6728 The new directory `gdb/sparclite' contains a program that demonstrates
6729 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6731 * New native hosts supported
6733 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6734 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6736 * New targets supported
6738 AMD 29k family via UDI a29k-amd-udi or udi29k
6740 * New file formats supported
6742 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6743 HPUX core files, and SCO 3.2v2 core files.
6747 Attaching to processes now works again; thanks for the many bug reports.
6749 We have also stomped on a bunch of core dumps caused by
6750 printf_filtered("%s") problems.
6752 We eliminated a copyright problem on the rpc and ptrace header files
6753 for VxWorks, which was discovered at the last minute during the 4.7
6754 release. You should now be able to build a VxWorks GDB.
6756 You can now interrupt gdb while an attached process is running. This
6757 will cause the attached process to stop, and give control back to GDB.
6759 We fixed problems caused by using too many file descriptors
6760 for reading symbols from object files and libraries. This was
6761 especially a problem for programs that used many (~100) shared
6764 The `step' command now only enters a subroutine if there is line number
6765 information for the subroutine. Otherwise it acts like the `next'
6766 command. Previously, `step' would enter subroutines if there was
6767 any debugging information about the routine. This avoids problems
6768 when using `cc -g1' on MIPS machines.
6770 * Internal improvements
6772 GDB's internal interfaces have been improved to make it easier to support
6773 debugging of multiple languages in the future.
6775 GDB now uses a common structure for symbol information internally.
6776 Minimal symbols (derived from linkage symbols in object files), partial
6777 symbols (from a quick scan of debug information), and full symbols
6778 contain a common subset of information, making it easier to write
6779 shared code that handles any of them.
6781 * New command line options
6783 We now accept --silent as an alias for --quiet.
6787 The memory-mapped-malloc library is now licensed under the GNU Library
6788 General Public License.
6790 *** Changes in GDB-4.7:
6792 * Host/native/target split
6794 GDB has had some major internal surgery to untangle the support for
6795 hosts and remote targets. Now, when you configure GDB for a remote
6796 target, it will no longer load in all of the support for debugging
6797 local programs on the host. When fully completed and tested, this will
6798 ensure that arbitrary host/target combinations are possible.
6800 The primary conceptual shift is to separate the non-portable code in
6801 GDB into three categories. Host specific code is required any time GDB
6802 is compiled on that host, regardless of the target. Target specific
6803 code relates to the peculiarities of the target, but can be compiled on
6804 any host. Native specific code is everything else: it can only be
6805 built when the host and target are the same system. Child process
6806 handling and core file support are two common `native' examples.
6808 GDB's use of /proc for controlling Unix child processes is now cleaner.
6809 It has been split out into a single module under the `target_ops' vector,
6810 plus two native-dependent functions for each system that uses /proc.
6812 * New hosts supported
6814 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6815 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6816 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6818 * New targets supported
6820 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6821 68030 and CPU32 m68030-*-*, m68332-*-*
6823 * New native hosts supported
6825 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6826 (386bsd is not well tested yet)
6827 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6829 * New file formats supported
6831 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6832 supports reading of `a.out.adobe' object files, which are an a.out
6833 format extended with minimal information about multiple sections.
6837 `show copying' is the same as the old `info copying'.
6838 `show warranty' is the same as `info warrantee'.
6839 These were renamed for consistency. The old commands continue to work.
6841 `info handle' is a new alias for `info signals'.
6843 You can now define pre-command hooks, which attach arbitrary command
6844 scripts to any command. The commands in the hook will be executed
6845 prior to the user's command. You can also create a hook which will be
6846 executed whenever the program stops. See gdb.texinfo.
6850 We now deal with Cfront style name mangling, and can even extract type
6851 info from mangled symbols. GDB can automatically figure out which
6852 symbol mangling style your C++ compiler uses.
6854 Calling of methods and virtual functions has been improved as well.
6858 The crash that occured when debugging Sun Ansi-C compiled binaries is
6859 fixed. This was due to mishandling of the extra N_SO stabs output
6862 We also finally got Ultrix 4.2 running in house, and fixed core file
6863 support, with help from a dozen people on the net.
6865 John M. Farrell discovered that the reason that single-stepping was so
6866 slow on all of the Mips based platforms (primarily SGI and DEC) was
6867 that we were trying to demangle and lookup a symbol used for internal
6868 purposes on every instruction that was being stepped through. Changing
6869 the name of that symbol so that it couldn't be mistaken for a C++
6870 mangled symbol sped things up a great deal.
6872 Rich Pixley sped up symbol lookups in general by getting much smarter
6873 about when C++ symbol mangling is necessary. This should make symbol
6874 completion (TAB on the command line) much faster. It's not as fast as
6875 we'd like, but it's significantly faster than gdb-4.6.
6879 A new user controllable variable 'call_scratch_address' can
6880 specify the location of a scratch area to be used when GDB
6881 calls a function in the target. This is necessary because the
6882 usual method of putting the scratch area on the stack does not work
6883 in systems that have separate instruction and data spaces.
6885 We integrated changes to support the 29k UDI (Universal Debugger
6886 Interface), but discovered at the last minute that we didn't have all
6887 of the appropriate copyright paperwork. We are working with AMD to
6888 resolve this, and hope to have it available soon.
6892 We have sped up the remote serial line protocol, especially for targets
6893 with lots of registers. It now supports a new `expedited status' ('T')
6894 message which can be used in place of the existing 'S' status message.
6895 This allows the remote stub to send only the registers that GDB
6896 needs to make a quick decision about single-stepping or conditional
6897 breakpoints, eliminating the need to fetch the entire register set for
6898 each instruction being stepped through.
6900 The GDB remote serial protocol now implements a write-through cache for
6901 registers, only re-reading the registers if the target has run.
6903 There is also a new remote serial stub for SPARC processors. You can
6904 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6905 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6906 processor with a serial port.
6910 Configure.in files have become much easier to read and modify. A new
6911 `table driven' format makes it more obvious what configurations are
6912 supported, and what files each one uses.
6916 There is a new opcodes library which will eventually contain all of the
6917 disassembly routines and opcode tables. At present, it only contains
6918 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6919 disassembler (binutils/objdump) to share these routines.
6921 The libiberty library is now copylefted under the GNU Library General
6922 Public License. This allows more liberal use, and was done so libg++
6923 can use it. This makes no difference to GDB, since the Library License
6924 grants all the rights from the General Public License.
6928 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6929 reference to the stabs symbol info used by the debugger. It is (as far
6930 as we know) the only published document on this fascinating topic. We
6931 encourage you to read it, compare it to the stabs information on your
6932 system, and send improvements on the document in general (to
6933 bug-gdb@prep.ai.mit.edu).
6935 And, of course, many bugs have been fixed.
6938 *** Changes in GDB-4.6:
6940 * Better support for C++ function names
6942 GDB now accepts as input the "demangled form" of C++ overloaded function
6943 names and member function names, and can do command completion on such names
6944 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6945 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6946 Make use of command completion, it is your friend.
6948 GDB also now accepts a variety of C++ mangled symbol formats. They are
6949 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6950 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6951 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6952 for the list of formats.
6954 * G++ symbol mangling problem
6956 Recent versions of gcc have a bug in how they emit debugging information for
6957 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6958 directory) can be applied to gcc to fix the problem. Alternatively, if you
6959 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6960 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6961 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6964 * New 'maintenance' command
6966 All of the commands related to hacking GDB internals have been moved out of
6967 the main command set, and now live behind the 'maintenance' command. This
6968 can also be abbreviated as 'mt'. The following changes were made:
6970 dump-me -> maintenance dump-me
6971 info all-breakpoints -> maintenance info breakpoints
6972 printmsyms -> maintenance print msyms
6973 printobjfiles -> maintenance print objfiles
6974 printpsyms -> maintenance print psymbols
6975 printsyms -> maintenance print symbols
6977 The following commands are new:
6979 maintenance demangle Call internal GDB demangler routine to
6980 demangle a C++ link name and prints the result.
6981 maintenance print type Print a type chain for a given symbol
6983 * Change to .gdbinit file processing
6985 We now read the $HOME/.gdbinit file before processing the argv arguments
6986 (e.g. reading symbol files or core files). This allows global parameters to
6987 be set, which will apply during the symbol reading. The ./.gdbinit is still
6988 read after argv processing.
6990 * New hosts supported
6992 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6994 GNU/Linux support i386-unknown-linux or linux
6996 We are also including code to support the HP/PA running BSD and HPUX. This
6997 is almost guaranteed not to work, as we didn't have time to test or build it
6998 for this release. We are including it so that the more adventurous (or
6999 masochistic) of you can play with it. We also had major problems with the
7000 fact that the compiler that we got from HP doesn't support the -g option.
7003 * New targets supported
7005 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7007 * More smarts about finding #include files
7009 GDB now remembers the compilation directory for all include files, and for
7010 all files from which C is generated (like yacc and lex sources). This
7011 greatly improves GDB's ability to find yacc/lex sources, and include files,
7012 especially if you are debugging your program from a directory different from
7013 the one that contains your sources.
7015 We also fixed a bug which caused difficulty with listing and setting
7016 breakpoints in include files which contain C code. (In the past, you had to
7017 try twice in order to list an include file that you hadn't looked at before.)
7019 * Interesting infernals change
7021 GDB now deals with arbitrary numbers of sections, where the symbols for each
7022 section must be relocated relative to that section's landing place in the
7023 target's address space. This work was needed to support ELF with embedded
7024 stabs used by Solaris-2.0.
7026 * Bug fixes (of course!)
7028 There have been loads of fixes for the following things:
7029 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7030 i960, stabs, DOS(GO32), procfs, etc...
7032 See the ChangeLog for details.
7034 *** Changes in GDB-4.5:
7036 * New machines supported (host and target)
7038 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7040 SGI Irix-4.x mips-sgi-irix4 or iris4
7042 * New malloc package
7044 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7045 Mmalloc is capable of handling mutiple heaps of memory. It is also
7046 capable of saving a heap to a file, and then mapping it back in later.
7047 This can be used to greatly speedup the startup of GDB by using a
7048 pre-parsed symbol table which lives in a mmalloc managed heap. For
7049 more details, please read mmalloc/mmalloc.texi.
7053 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7054 'help info proc' for details.
7056 * MIPS ecoff symbol table format
7058 The code that reads MIPS symbol table format is now supported on all hosts.
7059 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7062 * File name changes for MS-DOS
7064 Many files in the config directories have been renamed to make it easier to
7065 support GDB on MS-DOSe systems (which have very restrictive file name
7066 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7067 environment) is close to working but has some remaining problems. Note
7068 that debugging of DOS programs is not supported, due to limitations
7069 in the ``operating system'', but it can be used to host cross-debugging.
7071 * Cross byte order fixes
7073 Many fixes have been made to support cross debugging of Sparc and MIPS
7074 targets from hosts whose byte order differs.
7076 * New -mapped and -readnow options
7078 If memory-mapped files are available on your system through the 'mmap'
7079 system call, you can use the -mapped option on the `file' or
7080 `symbol-file' commands to cause GDB to write the symbols from your
7081 program into a reusable file. If the program you are debugging is
7082 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7083 Future GDB debugging sessions will notice the presence of this file,
7084 and will quickly map in symbol information from it, rather than reading
7085 the symbol table from the executable program. Using the '-mapped'
7086 option in a GDB `file' or `symbol-file' command has the same effect as
7087 starting GDB with the '-mapped' command-line option.
7089 You can cause GDB to read the entire symbol table immediately by using
7090 the '-readnow' option with any of the commands that load symbol table
7091 information (or on the GDB command line). This makes the command
7092 slower, but makes future operations faster.
7094 The -mapped and -readnow options are typically combined in order to
7095 build a `fred.syms' file that contains complete symbol information.
7096 A simple GDB invocation to do nothing but build a `.syms' file for future
7099 gdb -batch -nx -mapped -readnow programname
7101 The `.syms' file is specific to the host machine on which GDB is run.
7102 It holds an exact image of GDB's internal symbol table. It cannot be
7103 shared across multiple host platforms.
7105 * longjmp() handling
7107 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7108 siglongjmp() without losing control. This feature has not yet been ported to
7109 all systems. It currently works on many 386 platforms, all MIPS-based
7110 platforms (SGI, DECstation, etc), and Sun3/4.
7114 Preliminary work has been put in to support the new Solaris OS from Sun. At
7115 this time, it can control and debug processes, but it is not capable of
7120 As always, many many bug fixes. The major areas were with g++, and mipsread.
7121 People using the MIPS-based platforms should experience fewer mysterious
7122 crashes and trashed symbol tables.
7124 *** Changes in GDB-4.4:
7126 * New machines supported (host and target)
7128 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7130 BSD Reno on Vax vax-dec-bsd
7131 Ultrix on Vax vax-dec-ultrix
7133 * New machines supported (target)
7135 AMD 29000 embedded, using EBMON a29k-none-none
7139 GDB continues to improve its handling of C++. `References' work better.
7140 The demangler has also been improved, and now deals with symbols mangled as
7141 per the Annotated C++ Reference Guide.
7143 GDB also now handles `stabs' symbol information embedded in MIPS
7144 `ecoff' symbol tables. Since the ecoff format was not easily
7145 extensible to handle new languages such as C++, this appeared to be a
7146 good way to put C++ debugging info into MIPS binaries. This option
7147 will be supported in the GNU C compiler, version 2, when it is
7150 * New features for SVR4
7152 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7153 shared libraries. Debugging dynamically linked programs should present
7154 only minor differences from debugging statically linked programs.
7156 The `info proc' command will print out information about any process
7157 on an SVR4 system (including the one you are debugging). At the moment,
7158 it prints the address mappings of the process.
7160 If you bring up GDB on another SVR4 system, please send mail to
7161 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7163 * Better dynamic linking support in SunOS
7165 Reading symbols from shared libraries which contain debugging symbols
7166 now works properly. However, there remain issues such as automatic
7167 skipping of `transfer vector' code during function calls, which
7168 make it harder to debug code in a shared library, than to debug the
7169 same code linked statically.
7173 GDB is now using the latest `getopt' routines from the FSF. This
7174 version accepts the -- prefix for options with long names. GDB will
7175 continue to accept the old forms (-option and +option) as well.
7176 Various single letter abbreviations for options have been explicity
7177 added to the option table so that they won't get overshadowed in the
7178 future by other options that begin with the same letter.
7182 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7183 Many assorted bugs have been handled. Many more remain to be handled.
7184 See the various ChangeLog files (primarily in gdb and bfd) for details.
7187 *** Changes in GDB-4.3:
7189 * New machines supported (host and target)
7191 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7192 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7193 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7195 * Almost SCO Unix support
7197 We had hoped to support:
7198 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7199 (except for core file support), but we discovered very late in the release
7200 that it has problems with process groups that render gdb unusable. Sorry
7201 about that. I encourage people to fix it and post the fixes.
7203 * Preliminary ELF and DWARF support
7205 GDB can read ELF object files on System V Release 4, and can handle
7206 debugging records for C, in DWARF format, in ELF files. This support
7207 is preliminary. If you bring up GDB on another SVR4 system, please
7208 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7213 GDB now uses the latest `readline' library. One user-visible change
7214 is that two tabs will list possible command completions, which previously
7215 required typing M-? (meta-question mark, or ESC ?).
7219 The `stepi' bug that many of you noticed has been squashed.
7220 Many bugs in C++ have been handled. Many more remain to be handled.
7221 See the various ChangeLog files (primarily in gdb and bfd) for details.
7223 * State of the MIPS world (in case you wondered):
7225 GDB can understand the symbol tables emitted by the compilers
7226 supplied by most vendors of MIPS-based machines, including DEC. These
7227 symbol tables are in a format that essentially nobody else uses.
7229 Some versions of gcc come with an assembler post-processor called
7230 mips-tfile. This program is required if you want to do source-level
7231 debugging of gcc-compiled programs. I believe FSF does not ship
7232 mips-tfile with gcc version 1, but it will eventually come with gcc
7235 Debugging of g++ output remains a problem. g++ version 1.xx does not
7236 really support it at all. (If you're lucky, you should be able to get
7237 line numbers and stack traces to work, but no parameters or local
7238 variables.) With some work it should be possible to improve the
7241 When gcc version 2 is released, you will have somewhat better luck.
7242 However, even then you will get confusing results for inheritance and
7245 We will eventually provide full debugging of g++ output on
7246 DECstations. This will probably involve some kind of stabs-in-ecoff
7247 encapulation, but the details have not been worked out yet.
7250 *** Changes in GDB-4.2:
7252 * Improved configuration
7254 Only one copy of `configure' exists now, and it is not self-modifying.
7255 Porting BFD is simpler.
7259 The `step' and `next' commands now only stop at the first instruction
7260 of a source line. This prevents the multiple stops that used to occur
7261 in switch statements, for-loops, etc. `Step' continues to stop if a
7262 function that has debugging information is called within the line.
7266 Lots of small bugs fixed. More remain.
7268 * New host supported (not target)
7270 Intel 386 PC clone running Mach i386-none-mach
7273 *** Changes in GDB-4.1:
7275 * Multiple source language support
7277 GDB now has internal scaffolding to handle several source languages.
7278 It determines the type of each source file from its filename extension,
7279 and will switch expression parsing and number formatting to match the
7280 language of the function in the currently selected stack frame.
7281 You can also specifically set the language to be used, with
7282 `set language c' or `set language modula-2'.
7286 GDB now has preliminary support for the GNU Modula-2 compiler,
7287 currently under development at the State University of New York at
7288 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7289 continue through the fall of 1991 and into 1992.
7291 Other Modula-2 compilers are currently not supported, and attempting to
7292 debug programs compiled with them will likely result in an error as the
7293 symbol table is read. Feel free to work on it, though!
7295 There are hooks in GDB for strict type checking and range checking,
7296 in the `Modula-2 philosophy', but they do not currently work.
7300 GDB can now write to executable and core files (e.g. patch
7301 a variable's value). You must turn this switch on, specify
7302 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7303 by assigning a new value to a variable. Modifications take
7306 * Automatic SunOS shared library reading
7308 When you run your program, GDB automatically determines where its
7309 shared libraries (if any) have been loaded, and reads their symbols.
7310 The `share' command is no longer needed. This also works when
7311 examining core files.
7315 You can specify the number of lines that the `list' command shows.
7318 * New machines supported (host and target)
7320 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7321 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7322 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7324 * New hosts supported (not targets)
7326 IBM RT/PC: romp-ibm-aix or rtpc
7328 * New targets supported (not hosts)
7330 AMD 29000 embedded with COFF a29k-none-coff
7331 AMD 29000 embedded with a.out a29k-none-aout
7332 Ultracomputer remote kernel debug a29k-nyu-kern
7334 * New remote interfaces
7340 *** Changes in GDB-4.0:
7344 Wide output is wrapped at good places to make the output more readable.
7346 Gdb now supports cross-debugging from a host machine of one type to a
7347 target machine of another type. Communication with the target system
7348 is over serial lines. The ``target'' command handles connecting to the
7349 remote system; the ``load'' command will download a program into the
7350 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7351 also supports debugging of realtime processes running under VxWorks,
7352 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7353 stub on the target system.
7355 New CPUs supported include the AMD 29000 and Intel 960.
7357 GDB now reads object files and symbol tables via a ``binary file''
7358 library, which allows a single copy of GDB to debug programs of multiple
7359 object file types such as a.out and coff.
7361 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7362 refcard.dvi and refcard.ps are available to format it).
7365 * Control-Variable user interface simplified
7367 All variables that control the operation of the debugger can be set
7368 by the ``set'' command, and displayed by the ``show'' command.
7370 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7371 ``Show prompt'' produces the response:
7372 Gdb's prompt is new-gdb=>.
7374 What follows are the NEW set commands. The command ``help set'' will
7375 print a complete list of old and new set commands. ``help set FOO''
7376 will give a longer description of the variable FOO. ``show'' will show
7377 all of the variable descriptions and their current settings.
7379 confirm on/off: Enables warning questions for operations that are
7380 hard to recover from, e.g. rerunning the program while
7381 it is already running. Default is ON.
7383 editing on/off: Enables EMACS style command line editing
7384 of input. Previous lines can be recalled with
7385 control-P, the current line can be edited with control-B,
7386 you can search for commands with control-R, etc.
7389 history filename NAME: NAME is where the gdb command history
7390 will be stored. The default is .gdb_history,
7391 or the value of the environment variable
7394 history size N: The size, in commands, of the command history. The
7395 default is 256, or the value of the environment variable
7398 history save on/off: If this value is set to ON, the history file will
7399 be saved after exiting gdb. If set to OFF, the
7400 file will not be saved. The default is OFF.
7402 history expansion on/off: If this value is set to ON, then csh-like
7403 history expansion will be performed on
7404 command line input. The default is OFF.
7406 radix N: Sets the default radix for input and output. It can be set
7407 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7408 in the current radix, so "set radix 10" is always a no-op.
7410 height N: This integer value is the number of lines on a page. Default
7411 is 24, the current `stty rows'' setting, or the ``li#''
7412 setting from the termcap entry matching the environment
7415 width N: This integer value is the number of characters on a line.
7416 Default is 80, the current `stty cols'' setting, or the ``co#''
7417 setting from the termcap entry matching the environment
7420 Note: ``set screensize'' is obsolete. Use ``set height'' and
7421 ``set width'' instead.
7423 print address on/off: Print memory addresses in various command displays,
7424 such as stack traces and structure values. Gdb looks
7425 more ``symbolic'' if you turn this off; it looks more
7426 ``machine level'' with it on. Default is ON.
7428 print array on/off: Prettyprint arrays. New convenient format! Default
7431 print demangle on/off: Print C++ symbols in "source" form if on,
7434 print asm-demangle on/off: Same, for assembler level printouts
7437 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7440 * Support for Epoch Environment.
7442 The epoch environment is a version of Emacs v18 with windowing. One
7443 new command, ``inspect'', is identical to ``print'', except that if you
7444 are running in the epoch environment, the value is printed in its own
7448 * Support for Shared Libraries
7450 GDB can now debug programs and core files that use SunOS shared libraries.
7451 Symbols from a shared library cannot be referenced
7452 before the shared library has been linked with the program (this
7453 happens after you type ``run'' and before the function main() is entered).
7454 At any time after this linking (including when examining core files
7455 from dynamically linked programs), gdb reads the symbols from each
7456 shared library when you type the ``sharedlibrary'' command.
7457 It can be abbreviated ``share''.
7459 sharedlibrary REGEXP: Load shared object library symbols for files
7460 matching a unix regular expression. No argument
7461 indicates to load symbols for all shared libraries.
7463 info sharedlibrary: Status of loaded shared libraries.
7468 A watchpoint stops execution of a program whenever the value of an
7469 expression changes. Checking for this slows down execution
7470 tremendously whenever you are in the scope of the expression, but is
7471 quite useful for catching tough ``bit-spreader'' or pointer misuse
7472 problems. Some machines such as the 386 have hardware for doing this
7473 more quickly, and future versions of gdb will use this hardware.
7475 watch EXP: Set a watchpoint (breakpoint) for an expression.
7477 info watchpoints: Information about your watchpoints.
7479 delete N: Deletes watchpoint number N (same as breakpoints).
7480 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7481 enable N: Re-enables watchpoint number N (same as breakpoints).
7484 * C++ multiple inheritance
7486 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7489 * C++ exception handling
7491 Gdb now supports limited C++ exception handling. Besides the existing
7492 ability to breakpoint on an exception handler, gdb can breakpoint on
7493 the raising of an exception (before the stack is peeled back to the
7496 catch FOO: If there is a FOO exception handler in the dynamic scope,
7497 set a breakpoint to catch exceptions which may be raised there.
7498 Multiple exceptions (``catch foo bar baz'') may be caught.
7500 info catch: Lists all exceptions which may be caught in the
7501 current stack frame.
7504 * Minor command changes
7506 The command ``call func (arg, arg, ...)'' now acts like the print
7507 command, except it does not print or save a value if the function's result
7508 is void. This is similar to dbx usage.
7510 The ``up'' and ``down'' commands now always print the frame they end up
7511 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7512 frames without printing.
7514 * New directory command
7516 'dir' now adds directories to the FRONT of the source search path.
7517 The path starts off empty. Source files that contain debug information
7518 about the directory in which they were compiled can be found even
7519 with an empty path; Sun CC and GCC include this information. If GDB can't
7520 find your source file in the current directory, type "dir .".
7522 * Configuring GDB for compilation
7524 For normal use, type ``./configure host''. See README or gdb.texinfo
7527 GDB now handles cross debugging. If you are remotely debugging between
7528 two different machines, type ``./configure host -target=targ''.
7529 Host is the machine where GDB will run; targ is the machine
7530 where the program that you are debugging will run.