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 test-settings KIND
88 A set of commands used by the testsuite for exercising the settings
94 The "help" command uses the title style to enhance the
95 readibility of its output by styling the classes and
99 Similarly to "help", the "apropos" command also uses the
100 title style for the command names. "apropos" accepts now
101 a flag "-v" (verbose) to show the full documentation
102 of matching commands and to use the highlight style to mark
103 the documentation parts matching REGEXP.
106 The "show style" and its subcommands are now styling
107 a style name in their output using its own style, to help
108 the user visualize the different styles.
110 set print raw-frame-arguments
111 show print raw-frame-arguments
113 These commands replace the similarly-named "set/show print raw
114 frame-arguments" commands (now with a dash instead of a space). The
115 old commands are now deprecated and may be removed in a future
118 maint test-options require-delimiter
119 maint test-options unknown-is-error
120 maint test-options unknown-is-operand
121 maint show test-options-completion-result
122 Commands used by the testsuite to validate the command options
125 * New command options, command completion
127 GDB now has a standard infrastructure to support dash-style command
128 options ('-OPT'). One benefit is that commands that use it can
129 easily support completion of command line arguments. Try "CMD
130 -[TAB]" or "help CMD" to find options supported by a command. Over
131 time, we intend to migrate most commands to this infrastructure. A
132 number of commands got support for new command options in this
135 ** The "print" and "compile print" commands now support a number of
136 options that allow overriding relevant global print settings as
137 set by "set print" subcommands:
141 -array-indexes [on|off]
142 -elements NUMBER|unlimited
146 -repeats NUMBER|unlimited
147 -static-members [on|off]
152 Note that because the "print"/"compile print" commands accept
153 arbitrary expressions which may look like options (including
154 abbreviations), if you specify any command option, then you must
155 use a double dash ("--") to mark the end of argument processing.
157 ** The "backtrace" command now supports a number of options that
158 allow overriding relevant global print settings as set by "set
159 backtrace" and "set print" subcommands:
161 -entry-values no|only|preferred|if-needed|both|compact|default
162 -frame-arguments all|scalars|none
163 -raw-frame-arguments [on|off]
167 In addition, the full/no-filters/hide qualifiers are now also
168 exposed as command options too:
174 ** The "frame apply", "tfaas" and "faas" commands similarly now
175 support the following options:
180 All options above can also be abbreviated. The argument of boolean
181 (on/off) options can be 0/1 too, and also the argument is assumed
182 "on" if omitted. This allows writing compact command invocations,
185 (gdb) p -r -p -o 0 -- *myptr
187 The above is equivalent to:
189 (gdb) print -raw -pretty -object off -- *myptr
191 * Completion improvements
193 ** GDB can now complete the options of the "thread apply all" and
194 "taas" commands, and their "-ascending" option can now be
197 ** GDB can now complete the options of the "info threads" command.
199 ** GDB can now complete the options of the "compile file" and
200 "compile code" commands. The "compile file" command now
201 completes on filenames.
203 ** GDB can now complete the backtrace command's
204 "full/no-filters/hide" qualifiers.
206 * In settings, you can now abbreviate "unlimited".
208 E.g., "set print elements u" is now equivalent to "set print
214 This lists all the possible completions for the rest of the line, if it
215 were to be given as a command itself. This is intended for use by MI
216 frontends in cases when separate CLI and MI channels cannot be used.
218 -catch-throw, -catch-rethrow, and -catch-catch
219 These can be used to catch C++ exceptions in a similar fashion to
220 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
224 The testsuite now creates the files gdb.cmd (containing the arguments
225 used to launch GDB) and gdb.in (containing all the commands sent to
226 GDB) in the output directory for each test script. Multiple invocations
227 are appended with .1, .2, .3 etc.
229 *** Changes in GDB 8.3
231 * GDB and GDBserver now support access to additional registers on
232 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
235 * GDB now has experimental support for the compilation and injection of
236 C++ source code into the inferior. This beta release does not include
237 support for several language features, such as templates, constructors,
240 This feature requires GCC 7.1 or higher built with libcp1.so
243 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
244 can be passed using the '[ADDRESS]:PORT' notation, or the regular
245 'ADDRESS:PORT' method.
247 * DWARF index cache: GDB can now automatically save indices of DWARF
248 symbols on disk to speed up further loading of the same binaries.
250 * Ada task switching is now supported on aarch64-elf targets when
251 debugging a program using the Ravenscar Profile. For more information,
252 see the "Tasking Support when using the Ravenscar Profile" section
253 in the GDB user manual.
255 * GDB in batch mode now exits with status 1 if the last command to be
258 * The RISC-V target now supports target descriptions.
260 * System call catchpoints now support system call aliases on FreeBSD.
261 When the ABI of a system call changes in FreeBSD, this is
262 implemented by leaving a compatibility system call using the old ABI
263 at the existing number and allocating a new system call number for
264 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
265 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
266 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
267 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
268 so that a system call catchpoint for the 'kevent' system call will
269 catch invocations of both the 'kevent' and 'freebsd11_kevent'
270 binaries. This ensures that 'kevent' system calls are caught for
271 binaries using either the old or new ABIs.
273 * Terminal styling is now available for the CLI and the TUI. GNU
274 Source Highlight can additionally be used to provide styling of
275 source code snippets. See the "set style" commands, below, for more
278 * Removed support for old demangling styles arm, edg, gnu, hp and
283 set debug compile-cplus-types
284 show debug compile-cplus-types
285 Control the display of debug output about type conversion in the
286 C++ compile feature. Commands have no effect while compiliong
291 Control whether debug output about files/functions skipping is
294 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
295 Apply a command to some frames.
296 FLAG arguments allow to control what output to produce and how to handle
297 errors raised when applying COMMAND to a frame.
300 Apply a command to all threads (ignoring errors and empty output).
301 Shortcut for 'thread apply all -s COMMAND'.
304 Apply a command to all frames (ignoring errors and empty output).
305 Shortcut for 'frame apply all -s COMMAND'.
308 Apply a command to all frames of all threads (ignoring errors and empty
310 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
312 maint set dwarf unwinders (on|off)
313 maint show dwarf unwinders
314 Control whether DWARF unwinders can be used.
317 Display a list of open files for a process.
321 Changes to the "frame", "select-frame", and "info frame" CLI commands.
322 These commands all now take a frame specification which
323 is either a frame level, or one of the keywords 'level', 'address',
324 'function', or 'view' followed by a parameter. Selecting a frame by
325 address, or viewing a frame outside the current backtrace now
326 requires the use of a keyword. Selecting a frame by level is
327 unchanged. The MI comment "-stack-select-frame" is unchanged.
329 target remote FILENAME
330 target extended-remote FILENAME
331 If FILENAME is a Unix domain socket, GDB will attempt to connect
332 to this socket instead of opening FILENAME as a character device.
334 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
335 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
336 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
337 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
338 These commands can now print only the searched entities
339 matching the provided regexp(s), giving a condition
340 on the entity names or entity types. The flag -q disables
341 printing headers or informations messages.
347 These commands now determine the syntax for the shown entities
348 according to the language chosen by `set language'. In particular,
349 `set language auto' means to automatically choose the language of
352 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
353 The 'thread apply' command accepts new FLAG arguments.
354 FLAG arguments allow to control what output to produce and how to handle
355 errors raised when applying COMMAND to a thread.
357 set tui tab-width NCHARS
358 show tui tab-width NCHARS
359 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
361 set style enabled [on|off]
363 Enable or disable terminal styling. Styling is enabled by default
364 on most hosts, but disabled by default when in batch mode.
366 set style sources [on|off]
368 Enable or disable source code styling. Source code styling is
369 enabled by default, but only takes effect if styling in general is
370 enabled, and if GDB was linked with GNU Source Highlight.
372 set style filename foreground COLOR
373 set style filename background COLOR
374 set style filename intensity VALUE
375 Control the styling of file names.
377 set style function foreground COLOR
378 set style function background COLOR
379 set style function intensity VALUE
380 Control the styling of function names.
382 set style variable foreground COLOR
383 set style variable background COLOR
384 set style variable intensity VALUE
385 Control the styling of variable names.
387 set style address foreground COLOR
388 set style address background COLOR
389 set style address intensity VALUE
390 Control the styling of addresses.
394 ** The default version of the MI interpreter is now 3 (-i=mi3).
396 ** The '-data-disassemble' MI command now accepts an '-a' option to
397 disassemble the whole function surrounding the given program
398 counter value or function name. Support for this feature can be
399 verified by using the "-list-features" command, which should
400 contain "data-disassemble-a-option".
402 ** Command responses and notifications that include a frame now include
403 the frame's architecture in a new "arch" attribute.
405 ** The output of information about multi-location breakpoints (which is
406 syntactically incorrect in MI 2) has changed in MI 3. This affects
407 the following commands and events:
411 - =breakpoint-created
412 - =breakpoint-modified
414 The -fix-multi-location-breakpoint-output command can be used to enable
415 this behavior with previous MI versions.
417 * New native configurations
419 GNU/Linux/RISC-V riscv*-*-linux*
420 FreeBSD/riscv riscv*-*-freebsd*
424 GNU/Linux/RISC-V riscv*-*-linux*
426 CSKY GNU/LINUX csky*-*-linux
427 FreeBSD/riscv riscv*-*-freebsd*
429 GNU/Linux/OpenRISC or1k*-*-linux*
433 GDB no longer supports native debugging on versions of MS-Windows
438 ** GDB no longer supports Python versions less than 2.6.
440 ** The gdb.Inferior type has a new 'progspace' property, which is the program
441 space associated to that inferior.
443 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
444 of objfiles associated to that program space.
446 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
447 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
450 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
451 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
452 correct and did not work properly.
454 ** The gdb.Value type has a new constructor, which is used to construct a
455 gdb.Value from a Python buffer object and a gdb.Type.
461 Enable or disable the undefined behavior sanitizer. This is
462 disabled by default, but passing --enable-ubsan=yes or
463 --enable-ubsan=auto to configure will enable it. Enabling this can
464 cause a performance penalty. The undefined behavior sanitizer was
465 first introduced in GCC 4.9.
467 *** Changes in GDB 8.2
469 * The 'set disassembler-options' command now supports specifying options
472 * The 'symbol-file' command now accepts an '-o' option to add a relative
473 offset to all sections.
475 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
476 a relative offset to all sections, but it allows to override the load
477 address of individual sections using '-s'.
479 * The 'add-symbol-file' command no longer requires the second argument
480 (address of the text section).
482 * The endianness used with the 'set endian auto' mode in the absence of
483 an executable selected for debugging is now the last endianness chosen
484 either by one of the 'set endian big' and 'set endian little' commands
485 or by inferring from the last executable used, rather than the startup
488 * The pager now allows a "c" response, meaning to disable the pager
489 for the rest of the current command.
491 * The commands 'info variables/functions/types' now show the source line
492 numbers of symbol definitions when available.
494 * 'info proc' now works on running processes on FreeBSD systems and core
495 files created on FreeBSD systems.
497 * C expressions can now use _Alignof, and C++ expressions can now use
500 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
501 the vector length while the process is running.
507 Control display of debugging info regarding the FreeBSD native target.
509 set|show varsize-limit
510 This new setting allows the user to control the maximum size of Ada
511 objects being printed when those objects have a variable type,
512 instead of that maximum size being hardcoded to 65536 bytes.
514 set|show record btrace cpu
515 Controls the processor to be used for enabling errata workarounds for
518 maint check libthread-db
519 Run integrity checks on the current inferior's thread debugging
522 maint set check-libthread-db (on|off)
523 maint show check-libthread-db
524 Control whether to run integrity checks on inferior specific thread
525 debugging libraries as they are loaded. The default is not to
530 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
532 ** The commands attached to a breakpoint can be set by assigning to
533 the breakpoint's "commands" field.
535 ** gdb.execute can now execute multi-line gdb commands.
537 ** The new functions gdb.convenience_variable and
538 gdb.set_convenience_variable can be used to get and set the value
539 of convenience variables.
541 ** A gdb.Parameter will no longer print the "set" help text on an
542 ordinary "set"; instead by default a "set" will be silent unless
543 the get_set_string method returns a non-empty string.
547 RiscV ELF riscv*-*-elf
549 * Removed targets and native configurations
551 m88k running OpenBSD m88*-*-openbsd*
552 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
553 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
554 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
556 * Aarch64/Linux hardware watchpoints improvements
558 Hardware watchpoints on unaligned addresses are now properly
559 supported when running Linux kernel 4.10 or higher: read and access
560 watchpoints are no longer spuriously missed, and all watchpoints
561 lengths between 1 and 8 bytes are supported. On older kernels,
562 watchpoints set on unaligned addresses are no longer missed, with
563 the tradeoff that there is a possibility of false hits being
568 --enable-codesign=CERT
569 This can be used to invoke "codesign -s CERT" after building gdb.
570 This option is useful on macOS, where code signing is required for
571 gdb to work properly.
573 --disable-gdbcli has been removed
574 This is now silently accepted, but does nothing.
576 *** Changes in GDB 8.1
578 * GDB now supports dynamically creating arbitrary register groups specified
579 in XML target descriptions. This allows for finer grain grouping of
580 registers on systems with a large amount of registers.
582 * The 'ptype' command now accepts a '/o' flag, which prints the
583 offsets and sizes of fields in a struct, like the pahole(1) tool.
585 * New "--readnever" command line option instructs GDB to not read each
586 symbol file's symbolic debug information. This makes startup faster
587 but at the expense of not being able to perform symbolic debugging.
588 This option is intended for use cases where symbolic debugging will
589 not be used, e.g., when you only need to dump the debuggee's core.
591 * GDB now uses the GNU MPFR library, if available, to emulate target
592 floating-point arithmetic during expression evaluation when the target
593 uses different floating-point formats than the host. At least version
594 3.1 of GNU MPFR is required.
596 * GDB now supports access to the guarded-storage-control registers and the
597 software-based guarded-storage broadcast control registers on IBM z14.
599 * On Unix systems, GDB now supports transmitting environment variables
600 that are to be set or unset to GDBserver. These variables will
601 affect the environment to be passed to the remote inferior.
603 To inform GDB of environment variables that are to be transmitted to
604 GDBserver, use the "set environment" command. Only user set
605 environment variables are sent to GDBserver.
607 To inform GDB of environment variables that are to be unset before
608 the remote inferior is started by the GDBserver, use the "unset
609 environment" command.
611 * Completion improvements
613 ** GDB can now complete function parameters in linespecs and
614 explicit locations without quoting. When setting breakpoints,
615 quoting around functions names to help with TAB-completion is
616 generally no longer necessary. For example, this now completes
619 (gdb) b function(in[TAB]
620 (gdb) b function(int)
622 Related, GDB is no longer confused with completing functions in
623 C++ anonymous namespaces:
626 (gdb) b (anonymous namespace)::[TAB][TAB]
627 (anonymous namespace)::a_function()
628 (anonymous namespace)::b_function()
630 ** GDB now has much improved linespec and explicit locations TAB
631 completion support, that better understands what you're
632 completing and offers better suggestions. For example, GDB no
633 longer offers data symbols as possible completions when you're
634 setting a breakpoint.
636 ** GDB now TAB-completes label symbol names.
638 ** The "complete" command now mimics TAB completion accurately.
640 * New command line options (gcore)
643 Dump all memory mappings.
645 * Breakpoints on C++ functions are now set on all scopes by default
647 By default, breakpoints on functions/methods are now interpreted as
648 specifying all functions with the given name ignoring missing
649 leading scopes (namespaces and classes).
651 For example, assuming a C++ program with symbols named:
656 both commands "break func()" and "break B::func()" set a breakpoint
659 You can use the new flag "-qualified" to override this. This makes
660 GDB interpret the specified function name as a complete
661 fully-qualified name instead. For example, using the same C++
662 program, the "break -q B::func" command sets a breakpoint on
663 "B::func", only. A parameter has been added to the Python
664 gdb.Breakpoint constructor to achieve the same result when creating
665 a breakpoint from Python.
667 * Breakpoints on functions marked with C++ ABI tags
669 GDB can now set breakpoints on functions marked with C++ ABI tags
670 (e.g., [abi:cxx11]). See here for a description of ABI tags:
671 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
673 Functions with a C++11 abi tag are demangled/displayed like this:
675 function[abi:cxx11](int)
678 You can now set a breakpoint on such functions simply as if they had
681 (gdb) b function(int)
683 Or if you need to disambiguate between tags, like:
685 (gdb) b function[abi:other_tag](int)
687 Tab completion was adjusted accordingly as well.
691 ** New events gdb.new_inferior, gdb.inferior_deleted, and
692 gdb.new_thread are emitted. See the manual for further
693 description of these.
695 ** A new function, "gdb.rbreak" has been added to the Python API.
696 This function allows the setting of a large number of breakpoints
697 via a regex pattern in Python. See the manual for further details.
699 ** Python breakpoints can now accept explicit locations. See the
700 manual for a further description of this feature.
703 * New features in the GDB remote stub, GDBserver
705 ** GDBserver is now able to start inferior processes with a
706 specified initial working directory.
708 The user can set the desired working directory to be used from
709 GDB using the new "set cwd" command.
711 ** New "--selftest" command line option runs some GDBserver self
712 tests. These self tests are disabled in releases.
714 ** On Unix systems, GDBserver now does globbing expansion and variable
715 substitution in inferior command line arguments.
717 This is done by starting inferiors using a shell, like GDB does.
718 See "set startup-with-shell" in the user manual for how to disable
719 this from GDB when using "target extended-remote". When using
720 "target remote", you can disable the startup with shell by using the
721 new "--no-startup-with-shell" GDBserver command line option.
723 ** On Unix systems, GDBserver now supports receiving environment
724 variables that are to be set or unset from GDB. These variables
725 will affect the environment to be passed to the inferior.
727 * When catching an Ada exception raised with a message, GDB now prints
728 the message in the catchpoint hit notification. In GDB/MI mode, that
729 information is provided as an extra field named "exception-message"
730 in the *stopped notification.
732 * Trait objects can now be inspected When debugging Rust code. This
733 requires compiler support which will appear in Rust 1.24.
737 QEnvironmentHexEncoded
738 Inform GDBserver of an environment variable that is to be passed to
739 the inferior when starting it.
742 Inform GDBserver of an environment variable that is to be unset
743 before starting the remote inferior.
746 Inform GDBserver that the environment should be reset (i.e.,
747 user-set environment variables should be unset).
750 Indicates whether the inferior must be started with a shell or not.
753 Tell GDBserver that the inferior to be started should use a specific
756 * The "maintenance print c-tdesc" command now takes an optional
757 argument which is the file name of XML target description.
759 * The "maintenance selftest" command now takes an optional argument to
760 filter the tests to be run.
762 * The "enable", and "disable" commands now accept a range of
763 breakpoint locations, e.g. "enable 1.3-5".
768 Set and show the current working directory for the inferior.
771 Set and show compilation command used for compiling and injecting code
772 with the 'compile' commands.
774 set debug separate-debug-file
775 show debug separate-debug-file
776 Control the display of debug output about separate debug file search.
778 set dump-excluded-mappings
779 show dump-excluded-mappings
780 Control whether mappings marked with the VM_DONTDUMP flag should be
781 dumped when generating a core file.
784 List the registered selftests.
787 Start the debugged program stopping at the first instruction.
790 Control display of debugging messages related to OpenRISC targets.
792 set|show print type nested-type-limit
793 Set and show the limit of nesting level for nested types that the
794 type printer will show.
796 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
799 * Safer/improved support for debugging with no debug info
801 GDB no longer assumes functions with no debug information return
804 This means that GDB now refuses to call such functions unless you
805 tell it the function's type, by either casting the call to the
806 declared return type, or by casting the function to a function
807 pointer of the right type, and calling that:
809 (gdb) p getenv ("PATH")
810 'getenv' has unknown return type; cast the call to its declared return type
811 (gdb) p (char *) getenv ("PATH")
812 $1 = 0x7fffffffe "/usr/local/bin:/"...
813 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
814 $2 = 0x7fffffffe "/usr/local/bin:/"...
816 Similarly, GDB no longer assumes that global variables with no debug
817 info have type 'int', and refuses to print the variable's value
818 unless you tell it the variable's type:
821 'var' has unknown type; cast it to its declared type
825 * New native configurations
827 FreeBSD/aarch64 aarch64*-*-freebsd*
828 FreeBSD/arm arm*-*-freebsd*
832 FreeBSD/aarch64 aarch64*-*-freebsd*
833 FreeBSD/arm arm*-*-freebsd*
834 OpenRISC ELF or1k*-*-elf
836 * Removed targets and native configurations
838 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
840 *** Changes in GDB 8.0
842 * GDB now supports access to the PKU register on GNU/Linux. The register is
843 added by the Memory Protection Keys for Userspace feature which will be
844 available in future Intel CPUs.
846 * GDB now supports C++11 rvalue references.
850 ** New functions to start, stop and access a running btrace recording.
851 ** Rvalue references are now supported in gdb.Type.
853 * GDB now supports recording and replaying rdrand and rdseed Intel 64
856 * Building GDB and GDBserver now requires a C++11 compiler.
858 For example, GCC 4.8 or later.
860 It is no longer possible to build GDB or GDBserver with a C
861 compiler. The --disable-build-with-cxx configure option has been
864 * Building GDB and GDBserver now requires GNU make >= 3.81.
866 It is no longer supported to build GDB or GDBserver with another
867 implementation of the make program or an earlier version of GNU make.
869 * Native debugging on MS-Windows supports command-line redirection
871 Command-line arguments used for starting programs on MS-Windows can
872 now include redirection symbols supported by native Windows shells,
873 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
874 as "run", "start", and "set args", as well as the corresponding MI
877 * Support for thread names on MS-Windows.
879 GDB now catches and handles the special exception that programs
880 running on MS-Windows use to assign names to threads in the
883 * Support for Java programs compiled with gcj has been removed.
885 * User commands now accept an unlimited number of arguments.
886 Previously, only up to 10 was accepted.
888 * The "eval" command now expands user-defined command arguments.
890 This makes it easier to process a variable number of arguments:
895 eval "print $arg%d", $i
900 * Target descriptions can now describe registers for sparc32 and sparc64.
902 * GDB now supports DWARF version 5 (debug information format).
903 Its .debug_names index is not yet supported.
905 * New native configurations
907 FreeBSD/mips mips*-*-freebsd
911 Synopsys ARC arc*-*-elf32
912 FreeBSD/mips mips*-*-freebsd
914 * Removed targets and native configurations
916 Alpha running FreeBSD alpha*-*-freebsd*
917 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
922 Erases all the flash memory regions reported by the target.
924 maint print arc arc-instruction address
925 Print internal disassembler information about instruction at a given address.
929 set disassembler-options
930 show disassembler-options
931 Controls the passing of target specific information to the disassembler.
932 If it is necessary to specify more than one disassembler option then
933 multiple options can be placed together into a comma separated list.
934 The default value is the empty string. Currently, the only supported
935 targets are ARM, PowerPC and S/390.
940 Erases all the flash memory regions reported by the target. This is
941 equivalent to the CLI command flash-erase.
943 -file-list-shared-libraries
944 List the shared libraries in the program. This is
945 equivalent to the CLI command "info shared".
948 Catchpoints stopping the program when Ada exceptions are
949 handled. This is equivalent to the CLI command "catch handlers".
951 *** Changes in GDB 7.12
953 * GDB and GDBserver now build with a C++ compiler by default.
955 The --enable-build-with-cxx configure option is now enabled by
956 default. One must now explicitly configure with
957 --disable-build-with-cxx in order to build with a C compiler. This
958 option will be removed in a future release.
960 * GDBserver now supports recording btrace without maintaining an active
963 * GDB now supports a negative repeat count in the 'x' command to examine
964 memory backward from the given address. For example:
967 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
968 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
969 (gdb) x/-5i 0x0000000000400580
970 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
971 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
972 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
973 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
974 0x40057b <main(int, char**)+25>:
975 callq 0x400536 <Func1(int, char const*)>
977 * Fortran: Support structures with fields of dynamic types and
978 arrays of dynamic types.
980 * The symbol dumping maintenance commands have new syntax.
981 maint print symbols [-pc address] [--] [filename]
982 maint print symbols [-objfile objfile] [-source source] [--] [filename]
983 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
984 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
985 maint print msymbols [-objfile objfile] [--] [filename]
987 * GDB now supports multibit bitfields and enums in target register
990 * New Python-based convenience function $_as_string(val), which returns
991 the textual representation of a value. This function is especially
992 useful to obtain the text label of an enum value.
994 * Intel MPX bound violation handling.
996 Segmentation faults caused by a Intel MPX boundary violation
997 now display the kind of violation (upper or lower), the memory
998 address accessed and the memory bounds, along with the usual
999 signal received and code location.
1003 Program received signal SIGSEGV, Segmentation fault
1004 Upper bound violation while accessing address 0x7fffffffc3b3
1005 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1006 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1008 * Rust language support.
1009 GDB now supports debugging programs written in the Rust programming
1010 language. See https://www.rust-lang.org/ for more information about
1013 * Support for running interpreters on specified input/output devices
1015 GDB now supports a new mechanism that allows frontends to provide
1016 fully featured GDB console views, as a better alternative to
1017 building such views on top of the "-interpreter-exec console"
1018 command. See the new "new-ui" command below. With that command,
1019 frontends can now start GDB in the traditional command-line mode
1020 running in an embedded terminal emulator widget, and create a
1021 separate MI interpreter running on a specified i/o device. In this
1022 way, GDB handles line editing, history, tab completion, etc. in the
1023 console all by itself, and the GUI uses the separate MI interpreter
1024 for its own control and synchronization, invisible to the command
1027 * The "catch syscall" command catches groups of related syscalls.
1029 The "catch syscall" command now supports catching a group of related
1030 syscalls using the 'group:' or 'g:' prefix.
1035 skip -gfile file-glob-pattern
1036 skip -function function
1037 skip -rfunction regular-expression
1038 A generalized form of the skip command, with new support for
1039 glob-style file names and regular expressions for function names.
1040 Additionally, a file spec and a function spec may now be combined.
1042 maint info line-table REGEXP
1043 Display the contents of GDB's internal line table data struture.
1046 Run any GDB unit tests that were compiled in.
1049 Start a new user interface instance running INTERP as interpreter,
1050 using the TTY file for input/output.
1054 ** gdb.Breakpoint objects have a new attribute "pending", which
1055 indicates whether the breakpoint is pending.
1056 ** Three new breakpoint-related events have been added:
1057 gdb.breakpoint_created, gdb.breakpoint_modified, and
1058 gdb.breakpoint_deleted.
1060 signal-event EVENTID
1061 Signal ("set") the given MS-Windows event object. This is used in
1062 conjunction with the Windows JIT debugging (AeDebug) support, where
1063 the OS suspends a crashing process until a debugger can attach to
1064 it. Resuming the crashing process, in order to debug it, is done by
1065 signalling an event.
1067 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1068 was added in GDBserver, including JIT compiling fast tracepoint's
1069 conditional expression bytecode into native code.
1071 * Support for various remote target protocols and ROM monitors has
1074 target m32rsdi Remote M32R debugging over SDI
1075 target mips MIPS remote debugging protocol
1076 target pmon PMON ROM monitor
1077 target ddb NEC's DDB variant of PMON for Vr4300
1078 target rockhopper NEC RockHopper variant of PMON
1079 target lsi LSI variant of PMO
1081 * Support for tracepoints and fast tracepoints on powerpc-linux,
1082 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1083 including JIT compiling fast tracepoint's conditional expression
1084 bytecode into native code.
1086 * MI async record =record-started now includes the method and format used for
1087 recording. For example:
1089 =record-started,thread-group="i1",method="btrace",format="bts"
1091 * MI async record =thread-selected now includes the frame field. For example:
1093 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1097 Andes NDS32 nds32*-*-elf
1099 *** Changes in GDB 7.11
1101 * GDB now supports debugging kernel-based threads on FreeBSD.
1103 * Per-inferior thread numbers
1105 Thread numbers are now per inferior instead of global. If you're
1106 debugging multiple inferiors, GDB displays thread IDs using a
1107 qualified INF_NUM.THR_NUM form. For example:
1111 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1112 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1113 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1114 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1116 As consequence, thread numbers as visible in the $_thread
1117 convenience variable and in Python's InferiorThread.num attribute
1118 are no longer unique between inferiors.
1120 GDB now maintains a second thread ID per thread, referred to as the
1121 global thread ID, which is the new equivalent of thread numbers in
1122 previous releases. See also $_gthread below.
1124 For backwards compatibility, MI's thread IDs always refer to global
1127 * Commands that accept thread IDs now accept the qualified
1128 INF_NUM.THR_NUM form as well. For example:
1131 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1134 * In commands that accept a list of thread IDs, you can now refer to
1135 all threads of an inferior using a star wildcard. GDB accepts
1136 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1137 refer to all threads of the current inferior. For example, "info
1140 * You can use "info threads -gid" to display the global thread ID of
1143 * The new convenience variable $_gthread holds the global number of
1146 * The new convenience variable $_inferior holds the number of the
1149 * GDB now displays the ID and name of the thread that hit a breakpoint
1150 or received a signal, if your program is multi-threaded. For
1153 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1154 Thread 1 "main" received signal SIGINT, Interrupt.
1156 * Record btrace now supports non-stop mode.
1158 * Support for tracepoints on aarch64-linux was added in GDBserver.
1160 * The 'record instruction-history' command now indicates speculative execution
1161 when using the Intel Processor Trace recording format.
1163 * GDB now allows users to specify explicit locations, bypassing
1164 the linespec parser. This feature is also available to GDB/MI
1167 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1168 GDB now is able to debug both AArch64 applications and ARM applications
1171 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1172 including JIT compiling fast tracepoint's conditional expression bytecode
1175 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1177 * "info threads", "info inferiors", "info display", "info checkpoints"
1178 and "maint info program-spaces" now list the corresponding items in
1179 ascending ID order, for consistency with all other "info" commands.
1181 * In Ada, the overloads selection menu has been enhanced to display the
1182 parameter types and the return types for the matching overloaded subprograms.
1186 maint set target-non-stop (on|off|auto)
1187 maint show target-non-stop
1188 Control whether GDB targets always operate in non-stop mode even if
1189 "set non-stop" is "off". The default is "auto", meaning non-stop
1190 mode is enabled if supported by the target.
1192 maint set bfd-sharing
1193 maint show bfd-sharing
1194 Control the reuse of bfd objects.
1197 show debug bfd-cache
1198 Control display of debugging info regarding bfd caching.
1202 Control display of debugging info regarding FreeBSD threads.
1204 set remote multiprocess-extensions-packet
1205 show remote multiprocess-extensions-packet
1206 Set/show the use of the remote protocol multiprocess extensions.
1208 set remote thread-events
1209 show remote thread-events
1210 Set/show the use of thread create/exit events.
1212 set ada print-signatures on|off
1213 show ada print-signatures"
1214 Control whether parameter types and return types are displayed in overloads
1215 selection menus. It is activaled (@code{on}) by default.
1219 Controls the maximum size of memory, in bytes, that GDB will
1220 allocate for value contents. Prevents incorrect programs from
1221 causing GDB to allocate overly large buffers. Default is 64k.
1223 * The "disassemble" command accepts a new modifier: /s.
1224 It prints mixed source+disassembly like /m with two differences:
1225 - disassembled instructions are now printed in program order, and
1226 - and source for all relevant files is now printed.
1227 The "/m" option is now considered deprecated: its "source-centric"
1228 output hasn't proved useful in practice.
1230 * The "record instruction-history" command accepts a new modifier: /s.
1231 It behaves exactly like /m and prints mixed source+disassembly.
1233 * The "set scheduler-locking" command supports a new mode "replay".
1234 It behaves like "off" in record mode and like "on" in replay mode.
1236 * Support for various ROM monitors has been removed:
1238 target dbug dBUG ROM monitor for Motorola ColdFire
1239 target picobug Motorola picobug monitor
1240 target dink32 DINK32 ROM monitor for PowerPC
1241 target m32r Renesas M32R/D ROM monitor
1242 target mon2000 mon2000 ROM monitor
1243 target ppcbug PPCBUG ROM monitor for PowerPC
1245 * Support for reading/writing memory and extracting values on architectures
1246 whose memory is addressable in units of any integral multiple of 8 bits.
1249 Allows to break when an Ada exception is handled.
1251 * New remote packets
1254 Indicates that an exec system call was executed.
1256 exec-events feature in qSupported
1257 The qSupported packet allows GDB to request support for exec
1258 events using the new 'gdbfeature' exec-event, and the qSupported
1259 response can contain the corresponding 'stubfeature'. Set and
1260 show commands can be used to display whether these features are enabled.
1263 Equivalent to interrupting with the ^C character, but works in
1266 thread created stop reason (T05 create:...)
1267 Indicates that the thread was just created and is stopped at entry.
1269 thread exit stop reply (w exitcode;tid)
1270 Indicates that the thread has terminated.
1273 Enables/disables thread create and exit event reporting. For
1274 example, this is used in non-stop mode when GDB stops a set of
1275 threads and synchronously waits for the their corresponding stop
1276 replies. Without exit events, if one of the threads exits, GDB
1277 would hang forever not knowing that it should no longer expect a
1278 stop for that same thread.
1281 Indicates that there are no resumed threads left in the target (all
1282 threads are stopped). The remote stub reports support for this stop
1283 reply to GDB's qSupported query.
1286 Enables/disables catching syscalls from the inferior process.
1287 The remote stub reports support for this packet to GDB's qSupported query.
1289 syscall_entry stop reason
1290 Indicates that a syscall was just called.
1292 syscall_return stop reason
1293 Indicates that a syscall just returned.
1295 * Extended-remote exec events
1297 ** GDB now has support for exec events on extended-remote Linux targets.
1298 For such targets with Linux kernels 2.5.46 and later, this enables
1299 follow-exec-mode and exec catchpoints.
1301 set remote exec-event-feature-packet
1302 show remote exec-event-feature-packet
1303 Set/show the use of the remote exec event feature.
1305 * Thread names in remote protocol
1307 The reply to qXfer:threads:read may now include a name attribute for each
1310 * Target remote mode fork and exec events
1312 ** GDB now has support for fork and exec events on target remote mode
1313 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1314 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1315 fork and exec catchpoints.
1317 * Remote syscall events
1319 ** GDB now has support for catch syscall on remote Linux targets,
1320 currently enabled on x86/x86_64 architectures.
1322 set remote catch-syscall-packet
1323 show remote catch-syscall-packet
1324 Set/show the use of the remote catch syscall feature.
1328 ** The -var-set-format command now accepts the zero-hexadecimal
1329 format. It outputs data in hexadecimal format with zero-padding on the
1334 ** gdb.InferiorThread objects have a new attribute "global_num",
1335 which refers to the thread's global thread ID. The existing
1336 "num" attribute now refers to the thread's per-inferior number.
1337 See "Per-inferior thread numbers" above.
1338 ** gdb.InferiorThread objects have a new attribute "inferior", which
1339 is the Inferior object the thread belongs to.
1341 *** Changes in GDB 7.10
1343 * Support for process record-replay and reverse debugging on aarch64*-linux*
1344 targets has been added. GDB now supports recording of A64 instruction set
1345 including advance SIMD instructions.
1347 * Support for Sun's version of the "stabs" debug file format has been removed.
1349 * GDB now honors the content of the file /proc/PID/coredump_filter
1350 (PID is the process ID) on GNU/Linux systems. This file can be used
1351 to specify the types of memory mappings that will be included in a
1352 corefile. For more information, please refer to the manual page of
1353 "core(5)". GDB also has a new command: "set use-coredump-filter
1354 on|off". It allows to set whether GDB will read the content of the
1355 /proc/PID/coredump_filter file when generating a corefile.
1357 * The "info os" command on GNU/Linux can now display information on
1359 "info os cpus" Listing of all cpus/cores on the system
1361 * GDB has two new commands: "set serial parity odd|even|none" and
1362 "show serial parity". These allows to set or show parity for the
1365 * The "info source" command now displays the producer string if it was
1366 present in the debug info. This typically includes the compiler version
1367 and may include things like its command line arguments.
1369 * The "info dll", an alias of the "info sharedlibrary" command,
1370 is now available on all platforms.
1372 * Directory names supplied to the "set sysroot" commands may be
1373 prefixed with "target:" to tell GDB to access shared libraries from
1374 the target system, be it local or remote. This replaces the prefix
1375 "remote:". The default sysroot has been changed from "" to
1376 "target:". "remote:" is automatically converted to "target:" for
1377 backward compatibility.
1379 * The system root specified by "set sysroot" will be prepended to the
1380 filename of the main executable (if reported to GDB as absolute by
1381 the operating system) when starting processes remotely, and when
1382 attaching to already-running local or remote processes.
1384 * GDB now supports automatic location and retrieval of executable
1385 files from remote targets. Remote debugging can now be initiated
1386 using only a "target remote" or "target extended-remote" command
1387 (no "set sysroot" or "file" commands are required). See "New remote
1390 * The "dump" command now supports verilog hex format.
1392 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1394 * On GNU/Linux, GDB and gdbserver are now able to access executable
1395 and shared library files without a "set sysroot" command when
1396 attaching to processes running in different mount namespaces from
1397 the debugger. This makes it possible to attach to processes in
1398 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1399 See "New remote packets" below.
1401 * The "tui reg" command now provides completion for all of the
1402 available register groups, including target specific groups.
1404 * The HISTSIZE environment variable is no longer read when determining
1405 the size of GDB's command history. GDB now instead reads the dedicated
1406 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1407 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1412 ** Memory ports can now be unbuffered.
1416 ** gdb.Objfile objects have a new attribute "username",
1417 which is the name of the objfile as specified by the user,
1418 without, for example, resolving symlinks.
1419 ** You can now write frame unwinders in Python.
1420 ** gdb.Type objects have a new method "optimized_out",
1421 returning optimized out gdb.Value instance of this type.
1422 ** gdb.Value objects have new methods "reference_value" and
1423 "const_value" which return a reference to the value and a
1424 "const" version of the value respectively.
1428 maint print symbol-cache
1429 Print the contents of the symbol cache.
1431 maint print symbol-cache-statistics
1432 Print statistics of symbol cache usage.
1434 maint flush-symbol-cache
1435 Flush the contents of the symbol cache.
1439 Start branch trace recording using Branch Trace Store (BTS) format.
1442 Evaluate expression by using the compiler and print result.
1446 Explicit commands for enabling and disabling tui mode.
1449 set mpx bound on i386 and amd64
1450 Support for bound table investigation on Intel MPX enabled applications.
1454 Start branch trace recording using Intel Processor Trace format.
1457 Print information about branch tracing internals.
1459 maint btrace packet-history
1460 Print the raw branch tracing data.
1462 maint btrace clear-packet-history
1463 Discard the stored raw branch tracing data.
1466 Discard all branch tracing data. It will be fetched and processed
1467 anew by the next "record" command.
1472 Renamed from "set debug dwarf2-die".
1473 show debug dwarf-die
1474 Renamed from "show debug dwarf2-die".
1476 set debug dwarf-read
1477 Renamed from "set debug dwarf2-read".
1478 show debug dwarf-read
1479 Renamed from "show debug dwarf2-read".
1481 maint set dwarf always-disassemble
1482 Renamed from "maint set dwarf2 always-disassemble".
1483 maint show dwarf always-disassemble
1484 Renamed from "maint show dwarf2 always-disassemble".
1486 maint set dwarf max-cache-age
1487 Renamed from "maint set dwarf2 max-cache-age".
1488 maint show dwarf max-cache-age
1489 Renamed from "maint show dwarf2 max-cache-age".
1491 set debug dwarf-line
1492 show debug dwarf-line
1493 Control display of debugging info regarding DWARF line processing.
1496 show max-completions
1497 Set the maximum number of candidates to be considered during
1498 completion. The default value is 200. This limit allows GDB
1499 to avoid generating large completion lists, the computation of
1500 which can cause the debugger to become temporarily unresponsive.
1502 set history remove-duplicates
1503 show history remove-duplicates
1504 Control the removal of duplicate history entries.
1506 maint set symbol-cache-size
1507 maint show symbol-cache-size
1508 Control the size of the symbol cache.
1510 set|show record btrace bts buffer-size
1511 Set and show the size of the ring buffer used for branch tracing in
1513 The obtained size may differ from the requested size. Use "info
1514 record" to see the obtained buffer size.
1516 set debug linux-namespaces
1517 show debug linux-namespaces
1518 Control display of debugging info regarding Linux namespaces.
1520 set|show record btrace pt buffer-size
1521 Set and show the size of the ring buffer used for branch tracing in
1522 Intel Processor Trace format.
1523 The obtained size may differ from the requested size. Use "info
1524 record" to see the obtained buffer size.
1526 maint set|show btrace pt skip-pad
1527 Set and show whether PAD packets are skipped when computing the
1530 * The command 'thread apply all' can now support new option '-ascending'
1531 to call its specified command for all threads in ascending order.
1533 * Python/Guile scripting
1535 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1536 special section named `.debug_gdb_scripts'.
1538 * New remote packets
1540 qXfer:btrace-conf:read
1541 Return the branch trace configuration for the current thread.
1543 Qbtrace-conf:bts:size
1544 Set the requested ring buffer size for branch tracing in BTS format.
1547 Enable Intel Procesor Trace-based branch tracing for the current
1548 process. The remote stub reports support for this packet to GDB's
1551 Qbtrace-conf:pt:size
1552 Set the requested ring buffer size for branch tracing in Intel Processor
1556 Indicates a memory breakpoint instruction was executed, irrespective
1557 of whether it was GDB that planted the breakpoint or the breakpoint
1558 is hardcoded in the program. This is required for correct non-stop
1562 Indicates the target stopped for a hardware breakpoint. This is
1563 required for correct non-stop mode operation.
1566 Return information about files on the remote system.
1568 qXfer:exec-file:read
1569 Return the full absolute name of the file that was executed to
1570 create a process running on the remote system.
1573 Select the filesystem on which vFile: operations with filename
1574 arguments will operate. This is required for GDB to be able to
1575 access files on remote targets where the remote stub does not
1576 share a common filesystem with the inferior(s).
1579 Indicates that a fork system call was executed.
1582 Indicates that a vfork system call was executed.
1584 vforkdone stop reason
1585 Indicates that a vfork child of the specified process has executed
1586 an exec or exit, allowing the vfork parent to resume execution.
1588 fork-events and vfork-events features in qSupported
1589 The qSupported packet allows GDB to request support for fork and
1590 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1591 and the qSupported response can contain the corresponding
1592 'stubfeatures'. Set and show commands can be used to display
1593 whether these features are enabled.
1595 * Extended-remote fork events
1597 ** GDB now has support for fork events on extended-remote Linux
1598 targets. For targets with Linux kernels 2.5.60 and later, this
1599 enables follow-fork-mode and detach-on-fork for both fork and
1600 vfork, as well as fork and vfork catchpoints.
1602 * The info record command now shows the recording format and the
1603 branch tracing configuration for the current thread when using
1604 the btrace record target.
1605 For the BTS format, it shows the ring buffer size.
1607 * GDB now has support for DTrace USDT (Userland Static Defined
1608 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1610 * GDB now supports access to vector registers on S/390 GNU/Linux
1613 * Removed command line options
1615 -xdb HP-UX XDB compatibility mode.
1617 * Removed targets and native configurations
1619 HP/PA running HP-UX hppa*-*-hpux*
1620 Itanium running HP-UX ia64-*-hpux*
1622 * New configure options
1625 This configure option allows the user to build GDB with support for
1626 Intel Processor Trace (default: auto). This requires libipt.
1628 --with-libipt-prefix=PATH
1629 Specify the path to the version of libipt that GDB should use.
1630 $PATH/include should contain the intel-pt.h header and
1631 $PATH/lib should contain the libipt.so library.
1633 *** Changes in GDB 7.9.1
1637 ** Xmethods can now specify a result type.
1639 *** Changes in GDB 7.9
1641 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1645 ** You can now access frame registers from Python scripts.
1646 ** New attribute 'producer' for gdb.Symtab objects.
1647 ** gdb.Objfile objects have a new attribute "progspace",
1648 which is the gdb.Progspace object of the containing program space.
1649 ** gdb.Objfile objects have a new attribute "owner".
1650 ** gdb.Objfile objects have a new attribute "build_id",
1651 which is the build ID generated when the file was built.
1652 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1653 ** A new event "gdb.clear_objfiles" has been added, triggered when
1654 selecting a new file to debug.
1655 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1656 ** New function gdb.lookup_objfile.
1658 New events which are triggered when GDB modifies the state of the
1661 ** gdb.events.inferior_call_pre: Function call is about to be made.
1662 ** gdb.events.inferior_call_post: Function call has just been made.
1663 ** gdb.events.memory_changed: A memory location has been altered.
1664 ** gdb.events.register_changed: A register has been altered.
1666 * New Python-based convenience functions:
1668 ** $_caller_is(name [, number_of_frames])
1669 ** $_caller_matches(regexp [, number_of_frames])
1670 ** $_any_caller_is(name [, number_of_frames])
1671 ** $_any_caller_matches(regexp [, number_of_frames])
1673 * GDB now supports the compilation and injection of source code into
1674 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1675 to compile the source code to object code, and if successful, inject
1676 and execute that code within the current context of the inferior.
1677 Currently the C language is supported. The commands used to
1678 interface with this new feature are:
1680 compile code [-raw|-r] [--] [source code]
1681 compile file [-raw|-r] filename
1685 demangle [-l language] [--] name
1686 Demangle "name" in the specified language, or the current language
1687 if elided. This command is renamed from the "maint demangle" command.
1688 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1689 as "maint demangler-warning".
1691 queue-signal signal-name-or-number
1692 Queue a signal to be delivered to the thread when it is resumed.
1694 add-auto-load-scripts-directory directory
1695 Add entries to the list of directories from which to load auto-loaded
1698 maint print user-registers
1699 List all currently available "user" registers.
1701 compile code [-r|-raw] [--] [source code]
1702 Compile, inject, and execute in the inferior the executable object
1703 code produced by compiling the provided source code.
1705 compile file [-r|-raw] filename
1706 Compile and inject into the inferior the executable object code
1707 produced by compiling the source code stored in the filename
1710 * On resume, GDB now always passes the signal the program had stopped
1711 for to the thread the signal was sent to, even if the user changed
1712 threads before resuming. Previously GDB would often (but not
1713 always) deliver the signal to the thread that happens to be current
1716 * Conversely, the "signal" command now consistently delivers the
1717 requested signal to the current thread. GDB now asks for
1718 confirmation if the program had stopped for a signal and the user
1719 switched threads meanwhile.
1721 * "breakpoint always-inserted" modes "off" and "auto" merged.
1723 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1724 won't remove breakpoints from the target until all threads stop,
1725 even in non-stop mode. The "auto" mode has been removed, and "off"
1726 is now the default mode.
1730 set debug symbol-lookup
1731 show debug symbol-lookup
1732 Control display of debugging info regarding symbol lookup.
1736 ** The -list-thread-groups command outputs an exit-code field for
1737 inferiors that have exited.
1741 MIPS SDE mips*-sde*-elf*
1745 Support for these obsolete configurations has been removed.
1747 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1748 SGI Irix-5.x mips-*-irix5*
1749 SGI Irix-6.x mips-*-irix6*
1750 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1751 VAX running Ultrix vax-*-ultrix*
1753 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1754 and "assf"), have been removed. Use the "sharedlibrary" command, or
1755 its alias "share", instead.
1757 *** Changes in GDB 7.8
1759 * New command line options
1762 This is an alias for the --data-directory option.
1764 * GDB supports printing and modifying of variable length automatic arrays
1765 as specified in ISO C99.
1767 * The ARM simulator now supports instruction level tracing
1768 with or without disassembly.
1772 GDB now has support for scripting using Guile. Whether this is
1773 available is determined at configure time.
1774 Guile version 2.0 or greater is required.
1775 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1777 * New commands (for set/show, see "New options" below)
1781 Invoke CODE by passing it to the Guile interpreter.
1785 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1787 info auto-load guile-scripts [regexp]
1788 Print the list of automatically loaded Guile scripts.
1790 * The source command is now capable of sourcing Guile scripts.
1791 This feature is dependent on the debugger being built with Guile support.
1795 set print symbol-loading (off|brief|full)
1796 show print symbol-loading
1797 Control whether to print informational messages when loading symbol
1798 information for a file. The default is "full", but when debugging
1799 programs with large numbers of shared libraries the amount of output
1800 becomes less useful.
1802 set guile print-stack (none|message|full)
1803 show guile print-stack
1804 Show a stack trace when an error is encountered in a Guile script.
1806 set auto-load guile-scripts (on|off)
1807 show auto-load guile-scripts
1808 Control auto-loading of Guile script files.
1810 maint ada set ignore-descriptive-types (on|off)
1811 maint ada show ignore-descriptive-types
1812 Control whether the debugger should ignore descriptive types in Ada
1813 programs. The default is not to ignore the descriptive types. See
1814 the user manual for more details on descriptive types and the intended
1815 usage of this option.
1817 set auto-connect-native-target
1819 Control whether GDB is allowed to automatically connect to the
1820 native target for the run, attach, etc. commands when not connected
1821 to any target yet. See also "target native" below.
1823 set record btrace replay-memory-access (read-only|read-write)
1824 show record btrace replay-memory-access
1825 Control what memory accesses are allowed during replay.
1827 maint set target-async (on|off)
1828 maint show target-async
1829 This controls whether GDB targets operate in synchronous or
1830 asynchronous mode. Normally the default is asynchronous, if it is
1831 available; but this can be changed to more easily debug problems
1832 occurring only in synchronous mode.
1834 set mi-async (on|off)
1836 Control whether MI asynchronous mode is preferred. This supersedes
1837 "set target-async" of previous GDB versions.
1839 * "set target-async" is deprecated as a CLI option and is now an alias
1840 for "set mi-async" (only puts MI into async mode).
1842 * Background execution commands (e.g., "c&", "s&", etc.) are now
1843 possible ``out of the box'' if the target supports them. Previously
1844 the user would need to explicitly enable the possibility with the
1845 "set target-async on" command.
1847 * New features in the GDB remote stub, GDBserver
1849 ** New option --debug-format=option1[,option2,...] allows one to add
1850 additional text to each output. At present only timestamps
1851 are supported: --debug-format=timestamps.
1852 Timestamps can also be turned on with the
1853 "monitor set debug-format timestamps" command from GDB.
1855 * The 'record instruction-history' command now starts counting instructions
1856 at one. This also affects the instruction ranges reported by the
1857 'record function-call-history' command when given the /i modifier.
1859 * The command 'record function-call-history' supports a new modifier '/c' to
1860 indent the function names based on their call stack depth.
1861 The fields for the '/i' and '/l' modifier have been reordered.
1862 The source line range is now prefixed with 'at'.
1863 The instruction range is now prefixed with 'inst'.
1864 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1865 "record instruction-history" and "list" commands.
1867 * The ranges given as arguments to the 'record function-call-history' and
1868 'record instruction-history' commands are now inclusive.
1870 * The btrace record target now supports the 'record goto' command.
1871 For locations inside the execution trace, the back trace is computed
1872 based on the information stored in the execution trace.
1874 * The btrace record target supports limited reverse execution and replay.
1875 The target does not record data and therefore does not allow reading
1876 memory or registers.
1878 * The "catch syscall" command now works on s390*-linux* targets.
1880 * The "compare-sections" command is no longer specific to target
1881 remote. It now works with all targets.
1883 * All native targets are now consistently called "native".
1884 Consequently, the "target child", "target GNU", "target djgpp",
1885 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1886 commands have been replaced with "target native". The QNX/NTO port
1887 leaves the "procfs" target in place and adds a "native" target for
1888 consistency with other ports. The impact on users should be minimal
1889 as these commands previously either throwed an error, or were
1890 no-ops. The target's name is visible in the output of the following
1891 commands: "help target", "info target", "info files", "maint print
1894 * The "target native" command now connects to the native target. This
1895 can be used to launch native programs even when "set
1896 auto-connect-native-target" is set to off.
1898 * GDB now supports access to Intel MPX registers on GNU/Linux.
1900 * Support for Intel AVX-512 registers on GNU/Linux.
1901 Support displaying and modifying Intel AVX-512 registers
1902 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1904 * New remote packets
1906 qXfer:btrace:read's annex
1907 The qXfer:btrace:read packet supports a new annex 'delta' to read
1908 branch trace incrementally.
1912 ** Valid Python operations on gdb.Value objects representing
1913 structs/classes invoke the corresponding overloaded operators if
1915 ** New `Xmethods' feature in the Python API. Xmethods are
1916 additional methods or replacements for existing methods of a C++
1917 class. This feature is useful for those cases where a method
1918 defined in C++ source code could be inlined or optimized out by
1919 the compiler, making it unavailable to GDB.
1922 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1924 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1925 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1926 its alias "share", instead.
1928 * The commands "set remotebaud" and "show remotebaud" are no longer
1929 supported. Use "set serial baud" and "show serial baud" (respectively)
1934 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1935 target-async". The latter is left as a deprecated alias of the
1936 former for backward compatibility. If the target supports it,
1937 CLI background execution commands are now always possible by
1938 default, independently of whether the frontend stated a
1939 preference for asynchronous execution with "-gdb-set mi-async".
1940 Previously "-gdb-set target-async off" affected both MI execution
1941 commands and CLI execution commands.
1943 *** Changes in GDB 7.7
1945 * Improved support for process record-replay and reverse debugging on
1946 arm*-linux* targets. Support for thumb32 and syscall instruction
1947 recording has been added.
1949 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1951 * GDB now supports Fission DWP file format version 2.
1952 http://gcc.gnu.org/wiki/DebugFission
1954 * New convenience function "$_isvoid", to check whether an expression
1955 is void. A void expression is an expression where the type of the
1956 result is "void". For example, some convenience variables may be
1957 "void" when evaluated (e.g., "$_exitcode" before the execution of
1958 the program being debugged; or an undefined convenience variable).
1959 Another example, when calling a function whose return type is
1962 * The "maintenance print objfiles" command now takes an optional regexp.
1964 * The "catch syscall" command now works on arm*-linux* targets.
1966 * GDB now consistently shows "<not saved>" when printing values of
1967 registers the debug info indicates have not been saved in the frame
1968 and there's nowhere to retrieve them from
1969 (callee-saved/call-clobbered registers):
1974 (gdb) info registers rax
1977 Before, the former would print "<optimized out>", and the latter
1978 "*value not available*".
1980 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1985 ** Frame filters and frame decorators have been added.
1986 ** Temporary breakpoints are now supported.
1987 ** Line tables representation has been added.
1988 ** New attribute 'parent_type' for gdb.Field objects.
1989 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1990 ** New attribute 'name' for gdb.Type objects.
1994 Nios II ELF nios2*-*-elf
1995 Nios II GNU/Linux nios2*-*-linux
1996 Texas Instruments MSP430 msp430*-*-elf
1998 * Removed native configurations
2000 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2001 been removed. ELF variants of these configurations are kept supported.
2003 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2004 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2005 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2006 i[34567]86-*-openbsd3.[0-3]
2007 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2008 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2009 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2013 Like "catch throw", but catches a re-thrown exception.
2014 maint check-psymtabs
2015 Renamed from old "maint check-symtabs".
2017 Perform consistency checks on symtabs.
2018 maint expand-symtabs
2019 Expand symtabs matching an optional regexp.
2022 Display the details of GDB configure-time options.
2024 maint set|show per-command
2025 maint set|show per-command space
2026 maint set|show per-command time
2027 maint set|show per-command symtab
2028 Enable display of per-command gdb resource usage.
2030 remove-symbol-file FILENAME
2031 remove-symbol-file -a ADDRESS
2032 Remove a symbol file added via add-symbol-file. The file to remove
2033 can be identified by its filename or by an address that lies within
2034 the boundaries of this symbol file in memory.
2037 info exceptions REGEXP
2038 Display the list of Ada exceptions defined in the program being
2039 debugged. If provided, only the exceptions whose names match REGEXP
2044 set debug symfile off|on
2046 Control display of debugging info regarding reading symbol files and
2047 symbol tables within those files
2049 set print raw frame-arguments
2050 show print raw frame-arguments
2051 Set/show whether to print frame arguments in raw mode,
2052 disregarding any defined pretty-printers.
2054 set remote trace-status-packet
2055 show remote trace-status-packet
2056 Set/show the use of remote protocol qTStatus packet.
2060 Control display of debugging messages related to Nios II targets.
2064 Control whether target-assisted range stepping is enabled.
2066 set startup-with-shell
2067 show startup-with-shell
2068 Specifies whether Unix child processes are started via a shell or
2073 Use the target memory cache for accesses to the code segment. This
2074 improves performance of remote debugging (particularly disassembly).
2076 * You can now use a literal value 'unlimited' for options that
2077 interpret 0 or -1 as meaning "unlimited". E.g., "set
2078 trace-buffer-size unlimited" is now an alias for "set
2079 trace-buffer-size -1" and "set height unlimited" is now an alias for
2082 * The "set debug symtab-create" debugging option of GDB has been changed to
2083 accept a verbosity level. 0 means "off", 1 provides basic debugging
2084 output, and values of 2 or greater provides more verbose output.
2086 * New command-line options
2088 Display the details of GDB configure-time options.
2090 * The command 'tsave' can now support new option '-ctf' to save trace
2091 buffer in Common Trace Format.
2093 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2096 * GDB now implements the the C++ 'typeid' operator.
2098 * The new convenience variable $_exception holds the exception being
2099 thrown or caught at an exception-related catchpoint.
2101 * The exception-related catchpoints, like "catch throw", now accept a
2102 regular expression which can be used to filter exceptions by type.
2104 * The new convenience variable $_exitsignal is automatically set to
2105 the terminating signal number when the program being debugged dies
2106 due to an uncaught signal.
2110 ** All MI commands now accept an optional "--language" option.
2111 Support for this feature can be verified by using the "-list-features"
2112 command, which should contain "language-option".
2114 ** The new command -info-gdb-mi-command allows the user to determine
2115 whether a GDB/MI command is supported or not.
2117 ** The "^error" result record returned when trying to execute an undefined
2118 GDB/MI command now provides a variable named "code" whose content is the
2119 "undefined-command" error code. Support for this feature can be verified
2120 by using the "-list-features" command, which should contain
2121 "undefined-command-error-code".
2123 ** The -trace-save MI command can optionally save trace buffer in Common
2126 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2128 ** The command -data-list-register-values now accepts an optional
2129 "--skip-unavailable" option. When used, only the available registers
2132 ** The new command -trace-frame-collected dumps collected variables,
2133 computed expressions, tvars, memory and registers in a traceframe.
2135 ** The commands -stack-list-locals, -stack-list-arguments and
2136 -stack-list-variables now accept an option "--skip-unavailable".
2137 When used, only the available locals or arguments are displayed.
2139 ** The -exec-run command now accepts an optional "--start" option.
2140 When used, the command follows the same semantics as the "start"
2141 command, stopping the program's execution at the start of its
2142 main subprogram. Support for this feature can be verified using
2143 the "-list-features" command, which should contain
2144 "exec-run-start-option".
2146 ** The new commands -catch-assert and -catch-exceptions insert
2147 catchpoints stopping the program when Ada exceptions are raised.
2149 ** The new command -info-ada-exceptions provides the equivalent of
2150 the new "info exceptions" command.
2152 * New system-wide configuration scripts
2153 A GDB installation now provides scripts suitable for use as system-wide
2154 configuration scripts for the following systems:
2158 * GDB now supports target-assigned range stepping with remote targets.
2159 This improves the performance of stepping source lines by reducing
2160 the number of control packets from/to GDB. See "New remote packets"
2163 * GDB now understands the element 'tvar' in the XML traceframe info.
2164 It has the id of the collected trace state variables.
2166 * On S/390 targets that provide the transactional-execution feature,
2167 the program interruption transaction diagnostic block (TDB) is now
2168 represented as a number of additional "registers" in GDB.
2170 * New remote packets
2174 The vCont packet supports a new 'r' action, that tells the remote
2175 stub to step through an address range itself, without GDB
2176 involvemement at each single-step.
2178 qXfer:libraries-svr4:read's annex
2179 The previously unused annex of the qXfer:libraries-svr4:read packet
2180 is now used to support passing an argument list. The remote stub
2181 reports support for this argument list to GDB's qSupported query.
2182 The defined arguments are "start" and "prev", used to reduce work
2183 necessary for library list updating, resulting in significant
2186 * New features in the GDB remote stub, GDBserver
2188 ** GDBserver now supports target-assisted range stepping. Currently
2189 enabled on x86/x86_64 GNU/Linux targets.
2191 ** GDBserver now adds element 'tvar' in the XML in the reply to
2192 'qXfer:traceframe-info:read'. It has the id of the collected
2193 trace state variables.
2195 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2198 * New 'z' formatter for printing and examining memory, this displays the
2199 value as hexadecimal zero padded on the left to the size of the type.
2201 * GDB can now use Windows x64 unwinding data.
2203 * The "set remotebaud" command has been replaced by "set serial baud".
2204 Similarly, "show remotebaud" has been replaced by "show serial baud".
2205 The "set remotebaud" and "show remotebaud" commands are still available
2206 to provide backward compatibility with older versions of GDB.
2208 *** Changes in GDB 7.6
2210 * Target record has been renamed to record-full.
2211 Record/replay is now enabled with the "record full" command.
2212 This also affects settings that are associated with full record/replay
2213 that have been moved from "set/show record" to "set/show record full":
2215 set|show record full insn-number-max
2216 set|show record full stop-at-limit
2217 set|show record full memory-query
2219 * A new record target "record-btrace" has been added. The new target
2220 uses hardware support to record the control-flow of a process. It
2221 does not support replaying the execution, but it implements the
2222 below new commands for investigating the recorded execution log.
2223 This new recording method can be enabled using:
2227 The "record-btrace" target is only available on Intel Atom processors
2228 and requires a Linux kernel 2.6.32 or later.
2230 * Two new commands have been added for record/replay to give information
2231 about the recorded execution without having to replay the execution.
2232 The commands are only supported by "record btrace".
2234 record instruction-history prints the execution history at
2235 instruction granularity
2237 record function-call-history prints the execution history at
2238 function granularity
2240 * New native configurations
2242 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2243 FreeBSD/powerpc powerpc*-*-freebsd
2244 x86_64/Cygwin x86_64-*-cygwin*
2245 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2249 ARM AArch64 aarch64*-*-elf
2250 ARM AArch64 GNU/Linux aarch64*-*-linux
2251 Lynx 178 PowerPC powerpc-*-lynx*178
2252 x86_64/Cygwin x86_64-*-cygwin*
2253 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2255 * If the configured location of system.gdbinit file (as given by the
2256 --with-system-gdbinit option at configure time) is in the
2257 data-directory (as specified by --with-gdb-datadir at configure
2258 time) or in one of its subdirectories, then GDB will look for the
2259 system-wide init file in the directory specified by the
2260 --data-directory command-line option.
2262 * New command line options:
2264 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2265 other initialization files, unlike -nx which disables all of them.
2267 * Removed command line options
2269 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2272 * The 'ptype' and 'whatis' commands now accept an argument to control
2275 * 'info proc' now works on some core files.
2279 ** Vectors can be created with gdb.Type.vector.
2281 ** Python's atexit.register now works in GDB.
2283 ** Types can be pretty-printed via a Python API.
2285 ** Python 3 is now supported (in addition to Python 2.4 or later)
2287 ** New class gdb.Architecture exposes GDB's internal representation
2288 of architecture in the Python API.
2290 ** New method Frame.architecture returns the gdb.Architecture object
2291 corresponding to the frame's architecture.
2293 * New Python-based convenience functions:
2295 ** $_memeq(buf1, buf2, length)
2296 ** $_streq(str1, str2)
2298 ** $_regex(str, regex)
2300 * The 'cd' command now defaults to using '~' (the home directory) if not
2303 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2304 default for GCC since November 2000.
2306 * The command 'forward-search' can now be abbreviated as 'fo'.
2308 * The command 'info tracepoints' can now display 'installed on target'
2309 or 'not installed on target' for each non-pending location of tracepoint.
2311 * New configure options
2313 --enable-libmcheck/--disable-libmcheck
2314 By default, development versions are built with -lmcheck on hosts
2315 that support it, in order to help track memory corruption issues.
2316 Release versions, on the other hand, are built without -lmcheck
2317 by default. The --enable-libmcheck/--disable-libmcheck configure
2318 options allow the user to override that default.
2319 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2320 This configure option allows the user to build GDB with
2321 libbabeltrace using which GDB can read Common Trace Format data.
2323 * New commands (for set/show, see "New options" below)
2326 Catch signals. This is similar to "handle", but allows commands and
2327 conditions to be attached.
2330 List the BFDs known to GDB.
2332 python-interactive [command]
2334 Start a Python interactive prompt, or evaluate the optional command
2335 and print the result of expressions.
2338 "py" is a new alias for "python".
2340 enable type-printer [name]...
2341 disable type-printer [name]...
2342 Enable or disable type printers.
2346 ** For the Renesas Super-H architecture, the "regs" command has been removed
2347 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2352 set print type methods (on|off)
2353 show print type methods
2354 Control whether method declarations are displayed by "ptype".
2355 The default is to show them.
2357 set print type typedefs (on|off)
2358 show print type typedefs
2359 Control whether typedef definitions are displayed by "ptype".
2360 The default is to show them.
2362 set filename-display basename|relative|absolute
2363 show filename-display
2364 Control the way in which filenames is displayed.
2365 The default is "relative", which preserves previous behavior.
2367 set trace-buffer-size
2368 show trace-buffer-size
2369 Request target to change the size of trace buffer.
2371 set remote trace-buffer-size-packet auto|on|off
2372 show remote trace-buffer-size-packet
2373 Control the use of the remote protocol `QTBuffer:size' packet.
2377 Control display of debugging messages related to ARM AArch64.
2380 set debug coff-pe-read
2381 show debug coff-pe-read
2382 Control display of debugging messages related to reading of COFF/PE
2387 Control display of debugging messages related to Mach-O symbols
2390 set debug notification
2391 show debug notification
2392 Control display of debugging info for async remote notification.
2396 ** Command parameter changes are now notified using new async record
2397 "=cmd-param-changed".
2398 ** Trace frame changes caused by command "tfind" are now notified using
2399 new async record "=traceframe-changed".
2400 ** The creation, deletion and modification of trace state variables
2401 are now notified using new async records "=tsv-created",
2402 "=tsv-deleted" and "=tsv-modified".
2403 ** The start and stop of process record are now notified using new
2404 async record "=record-started" and "=record-stopped".
2405 ** Memory changes are now notified using new async record
2407 ** The data-disassemble command response will include a "fullname" field
2408 containing the absolute file name when source has been requested.
2409 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2410 command, to allow pattern filling of memory areas.
2411 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2412 library load/unload events.
2413 ** The response to breakpoint commands and breakpoint async records
2414 includes an "installed" field containing a boolean state about each
2415 non-pending tracepoint location is whether installed on target or not.
2416 ** Output of the "-trace-status" command includes a "trace-file" field
2417 containing the name of the trace file being examined. This field is
2418 optional, and only present when examining a trace file.
2419 ** The "fullname" field is now always present along with the "file" field,
2420 even if the file cannot be found by GDB.
2422 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2423 You must have the LZMA library available when configuring GDB for this
2424 feature to be enabled. For more information, see:
2425 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2427 * New remote packets
2430 Set the size of trace buffer. The remote stub reports support for this
2431 packet to gdb's qSupported query.
2434 Enable Branch Trace Store (BTS)-based branch tracing for the current
2435 thread. The remote stub reports support for this packet to gdb's
2439 Disable branch tracing for the current thread. The remote stub reports
2440 support for this packet to gdb's qSupported query.
2443 Read the traced branches for the current thread. The remote stub
2444 reports support for this packet to gdb's qSupported query.
2446 *** Changes in GDB 7.5
2448 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2449 for more x32 ABI info.
2451 * GDB now supports access to MIPS DSP registers on Linux targets.
2453 * GDB now supports debugging microMIPS binaries.
2455 * The "info os" command on GNU/Linux can now display information on
2456 several new classes of objects managed by the operating system:
2457 "info os procgroups" lists process groups
2458 "info os files" lists file descriptors
2459 "info os sockets" lists internet-domain sockets
2460 "info os shm" lists shared-memory regions
2461 "info os semaphores" lists semaphores
2462 "info os msg" lists message queues
2463 "info os modules" lists loaded kernel modules
2465 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2466 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2467 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2468 options and inspect the probe arguments using the new $_probe_arg family
2469 of convenience variables. You can obtain more information about SystemTap
2470 in <http://sourceware.org/systemtap/>.
2472 * GDB now supports reversible debugging on ARM, it allows you to
2473 debug basic ARM and THUMB instructions, and provides
2474 record/replay support.
2476 * The option "symbol-reloading" has been deleted as it is no longer used.
2480 ** GDB commands implemented in Python can now be put in command class
2483 ** The "maint set python print-stack on|off" is now deleted.
2485 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2486 apply "flag enum"-style pretty-printing to any enum.
2488 ** gdb.lookup_symbol can now work when there is no current frame.
2490 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2491 the source at which the symbol was defined.
2493 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2494 method 'value'. The former indicates whether the symbol needs a
2495 frame in order to compute its value, and the latter computes the
2498 ** A new method 'referenced_value' on gdb.Value objects which can
2499 dereference pointer as well as C++ reference values.
2501 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2502 which return the global and static blocks (as gdb.Block objects),
2503 of the underlying symbol table, respectively.
2505 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2506 object associated with a PC value.
2508 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2509 of the address range occupied by code for the current source line.
2511 * Go language support.
2512 GDB now supports debugging programs written in the Go programming
2515 * GDBserver now supports stdio connections.
2516 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2518 * The binary "gdbtui" can no longer be built or installed.
2519 Use "gdb -tui" instead.
2521 * GDB will now print "flag" enums specially. A flag enum is one where
2522 all the enumerator values have no bits in common when pairwise
2523 "and"ed. When printing a value whose type is a flag enum, GDB will
2524 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2525 (gdb) print (enum E) 3
2528 * The filename part of a linespec will now match trailing components
2529 of a source file name. For example, "break gcc/expr.c:1000" will
2530 now set a breakpoint in build/gcc/expr.c, but not
2531 build/libcpp/expr.c.
2533 * The "info proc" and "generate-core-file" commands will now also
2534 work on remote targets connected to GDBserver on Linux.
2536 * The command "info catch" has been removed. It has been disabled
2537 since December 2007.
2539 * The "catch exception" and "catch assert" commands now accept
2540 a condition at the end of the command, much like the "break"
2541 command does. For instance:
2543 (gdb) catch exception Constraint_Error if Barrier = True
2545 Previously, it was possible to add a condition to such catchpoints,
2546 but it had to be done as a second step, after the catchpoint had been
2547 created, using the "condition" command.
2549 * The "info static-tracepoint-marker" command will now also work on
2550 native Linux targets with in-process agent.
2552 * GDB can now set breakpoints on inlined functions.
2554 * The .gdb_index section has been updated to include symbols for
2555 inlined functions. GDB will ignore older .gdb_index sections by
2556 default, which could cause symbol files to be loaded more slowly
2557 until their .gdb_index sections can be recreated. The new command
2558 "set use-deprecated-index-sections on" will cause GDB to use any older
2559 .gdb_index sections it finds. This will restore performance, but the
2560 ability to set breakpoints on inlined functions will be lost in symbol
2561 files with older .gdb_index sections.
2563 The .gdb_index section has also been updated to record more information
2564 about each symbol. This speeds up the "info variables", "info functions"
2565 and "info types" commands when used with programs having the .gdb_index
2566 section, as well as speeding up debugging with shared libraries using
2567 the .gdb_index section.
2569 * Ada support for GDB/MI Variable Objects has been added.
2571 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2576 ** New command -info-os is the MI equivalent of "info os".
2578 ** Output logs ("set logging" and related) now include MI output.
2582 ** "set use-deprecated-index-sections on|off"
2583 "show use-deprecated-index-sections on|off"
2584 Controls the use of deprecated .gdb_index sections.
2586 ** "catch load" and "catch unload" can be used to stop when a shared
2587 library is loaded or unloaded, respectively.
2589 ** "enable count" can be used to auto-disable a breakpoint after
2592 ** "info vtbl" can be used to show the virtual method tables for
2593 C++ and Java objects.
2595 ** "explore" and its sub commands "explore value" and "explore type"
2596 can be used to recursively explore values and types of
2597 expressions. These commands are available only if GDB is
2598 configured with '--with-python'.
2600 ** "info auto-load" shows status of all kinds of auto-loaded files,
2601 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2602 sequences of commands files, "info auto-load python-scripts"
2603 shows status of auto-loading Python script files,
2604 "info auto-load local-gdbinit" shows status of loading init file
2605 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2606 status of inferior specific thread debugging shared library loading.
2608 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2609 and "show auto-load-scripts" commands have been deprecated, use their
2610 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2611 and "show auto-load python-scripts" counterparts instead.
2613 ** "dprintf location,format,args..." creates a dynamic printf, which
2614 is basically a breakpoint that does a printf and immediately
2615 resumes your program's execution, so it is like a printf that you
2616 can insert dynamically at runtime instead of at compiletime.
2618 ** "set print symbol"
2620 Controls whether GDB attempts to display the symbol, if any,
2621 corresponding to addresses it prints. This defaults to "on", but
2622 you can set it to "off" to restore GDB's previous behavior.
2624 * Deprecated commands
2626 ** For the Renesas Super-H architecture, the "regs" command has been
2627 deprecated, and "info all-registers" should be used instead.
2631 Renesas RL78 rl78-*-elf
2632 HP OpenVMS ia64 ia64-hp-openvms*
2634 * GDBserver supports evaluation of breakpoint conditions. When
2635 support is advertised by GDBserver, GDB may be told to send the
2636 breakpoint conditions in bytecode form to GDBserver. GDBserver
2637 will only report the breakpoint trigger to GDB when its condition
2642 set mips compression
2643 show mips compression
2644 Select the compressed ISA encoding used in functions that have no symbol
2645 information available. The encoding can be set to either of:
2648 and is updated automatically from ELF file flags if available.
2650 set breakpoint condition-evaluation
2651 show breakpoint condition-evaluation
2652 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2653 GDBserver ("target"). Default option "auto" chooses the most efficient
2655 This option can improve debugger efficiency depending on the speed of the
2659 Disable auto-loading globally.
2662 Show auto-loading setting of all kinds of auto-loaded files.
2664 set auto-load gdb-scripts on|off
2665 show auto-load gdb-scripts
2666 Control auto-loading of GDB canned sequences of commands files.
2668 set auto-load python-scripts on|off
2669 show auto-load python-scripts
2670 Control auto-loading of Python script files.
2672 set auto-load local-gdbinit on|off
2673 show auto-load local-gdbinit
2674 Control loading of init file (.gdbinit) from current directory.
2676 set auto-load libthread-db on|off
2677 show auto-load libthread-db
2678 Control auto-loading of inferior specific thread debugging shared library.
2680 set auto-load scripts-directory <dir1>[:<dir2>...]
2681 show auto-load scripts-directory
2682 Set a list of directories from which to load auto-loaded scripts.
2683 Automatically loaded Python scripts and GDB scripts are located in one
2684 of the directories listed by this option.
2685 The delimiter (':' above) may differ according to the host platform.
2687 set auto-load safe-path <dir1>[:<dir2>...]
2688 show auto-load safe-path
2689 Set a list of directories from which it is safe to auto-load files.
2690 The delimiter (':' above) may differ according to the host platform.
2692 set debug auto-load on|off
2693 show debug auto-load
2694 Control display of debugging info for auto-loading the files above.
2696 set dprintf-style gdb|call|agent
2698 Control the way in which a dynamic printf is performed; "gdb"
2699 requests a GDB printf command, while "call" causes dprintf to call a
2700 function in the inferior. "agent" requests that the target agent
2701 (such as GDBserver) do the printing.
2703 set dprintf-function <expr>
2704 show dprintf-function
2705 set dprintf-channel <expr>
2706 show dprintf-channel
2707 Set the function and optional first argument to the call when using
2708 the "call" style of dynamic printf.
2710 set disconnected-dprintf on|off
2711 show disconnected-dprintf
2712 Control whether agent-style dynamic printfs continue to be in effect
2713 after GDB disconnects.
2715 * New configure options
2717 --with-auto-load-dir
2718 Configure default value for the 'set auto-load scripts-directory'
2719 setting above. It defaults to '$debugdir:$datadir/auto-load',
2720 $debugdir representing global debugging info directories (available
2721 via 'show debug-file-directory') and $datadir representing GDB's data
2722 directory (available via 'show data-directory').
2724 --with-auto-load-safe-path
2725 Configure default value for the 'set auto-load safe-path' setting
2726 above. It defaults to the --with-auto-load-dir setting.
2728 --without-auto-load-safe-path
2729 Set 'set auto-load safe-path' to '/', effectively disabling this
2732 * New remote packets
2734 z0/z1 conditional breakpoints extension
2736 The z0/z1 breakpoint insertion packets have been extended to carry
2737 a list of conditional expressions over to the remote stub depending on the
2738 condition evaluation mode. The use of this extension can be controlled
2739 via the "set remote conditional-breakpoints-packet" command.
2743 Specify the signals which the remote stub may pass to the debugged
2744 program without GDB involvement.
2746 * New command line options
2748 --init-command=FILE, -ix Like --command, -x but execute it
2749 before loading inferior.
2750 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2751 execute it before loading inferior.
2753 *** Changes in GDB 7.4
2755 * GDB now handles ambiguous linespecs more consistently; the existing
2756 FILE:LINE support has been expanded to other types of linespecs. A
2757 breakpoint will now be set on all matching locations in all
2758 inferiors, and locations will be added or removed according to
2761 * GDB now allows you to skip uninteresting functions and files when
2762 stepping with the "skip function" and "skip file" commands.
2764 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2765 and "show remote hardware-watchpoint-length-limit". These allows to
2766 set or show the maximum length limit (in bytes) of a remote
2767 target hardware watchpoint.
2769 This allows e.g. to use "unlimited" hardware watchpoints with the
2770 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2771 watchpoints are slower than real hardware watchpoints but are
2772 significantly faster than gdb software watchpoints.
2776 ** The register_pretty_printer function in module gdb.printing now takes
2777 an optional `replace' argument. If True, the new printer replaces any
2780 ** The "maint set python print-stack on|off" command has been
2781 deprecated and will be deleted in GDB 7.5.
2782 A new command: "set python print-stack none|full|message" has
2783 replaced it. Additionally, the default for "print-stack" is
2784 now "message", which just prints the error message without
2787 ** A prompt substitution hook (prompt_hook) is now available to the
2790 ** A new Python module, gdb.prompt has been added to the GDB Python
2791 modules library. This module provides functionality for
2792 escape sequences in prompts (used by set/show
2793 extended-prompt). These escape sequences are replaced by their
2794 corresponding value.
2796 ** Python commands and convenience-functions located in
2797 'data-directory'/python/gdb/command and
2798 'data-directory'/python/gdb/function are now automatically loaded
2801 ** Blocks now provide four new attributes. global_block and
2802 static_block will return the global and static blocks
2803 respectively. is_static and is_global are boolean attributes
2804 that indicate if the block is one of those two types.
2806 ** Symbols now provide the "type" attribute, the type of the symbol.
2808 ** The "gdb.breakpoint" function has been deprecated in favor of
2811 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2812 of a function. This class is based on the "finish" command
2813 available in the CLI.
2815 ** Type objects for struct and union types now allow access to
2816 the fields using standard Python dictionary (mapping) methods.
2817 For example, "some_type['myfield']" now works, as does
2818 "some_type.items()".
2820 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2823 ** A new function, "deep_items" has been added to the gdb.types
2824 module in the GDB Python modules library. This function returns
2825 an iterator over the fields of a struct or union type. Unlike
2826 the standard Python "iteritems" method, it will recursively traverse
2827 any anonymous fields.
2831 ** "*stopped" events can report several new "reason"s, such as
2834 ** Breakpoint changes are now notified using new async records, like
2835 "=breakpoint-modified".
2837 ** New command -ada-task-info.
2839 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2840 $sdir specifies the default system locations of shared libraries.
2841 $pdir specifies the directory where the libpthread used by the application
2844 GDB no longer looks in $sdir and $pdir after it has searched the directories
2845 mentioned in libthread-db-search-path. If you want to search those
2846 directories, they must be specified in libthread-db-search-path.
2847 The default value of libthread-db-search-path on GNU/Linux and Solaris
2848 systems is now "$sdir:$pdir".
2850 $pdir is not supported by gdbserver, it is currently ignored.
2851 $sdir is supported by gdbserver.
2853 * New configure option --with-iconv-bin.
2854 When using the internationalization support like the one in the GNU C
2855 library, GDB will invoke the "iconv" program to get a list of supported
2856 character sets. If this program lives in a non-standard location, one can
2857 use this option to specify where to find it.
2859 * When natively debugging programs on PowerPC BookE processors running
2860 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2861 watchpoints, which specify a mask in addition to an address to watch.
2862 The mask specifies that some bits of an address (the bits which are
2863 reset in the mask) should be ignored when matching the address accessed
2864 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2865 section in the user manual for more details.
2867 * The new option --once causes GDBserver to stop listening for connections once
2868 the first connection is made. The listening port used by GDBserver will
2869 become available after that.
2871 * New commands "info macros" and "alias" have been added.
2873 * New function parameters suffix @entry specifies value of function parameter
2874 at the time the function got called. Entry values are available only since
2880 "!" is now an alias of the "shell" command.
2881 Note that no space is needed between "!" and SHELL COMMAND.
2885 watch EXPRESSION mask MASK_VALUE
2886 The watch command now supports the mask argument which allows creation
2887 of masked watchpoints, if the current architecture supports this feature.
2889 info auto-load-scripts [REGEXP]
2890 This command was formerly named "maintenance print section-scripts".
2891 It is now generally useful and is no longer a maintenance-only command.
2893 info macro [-all] [--] MACRO
2894 The info macro command has new options `-all' and `--'. The first for
2895 printing all definitions of a macro. The second for explicitly specifying
2896 the end of arguments and the beginning of the macro name in case the macro
2897 name starts with a hyphen.
2899 collect[/s] EXPRESSIONS
2900 The tracepoint collect command now takes an optional modifier "/s"
2901 that directs it to dereference pointer-to-character types and
2902 collect the bytes of memory up to a zero byte. The behavior is
2903 similar to what you see when you use the regular print command on a
2904 string. An optional integer following the "/s" sets a bound on the
2905 number of bytes that will be collected.
2908 The trace start command now interprets any supplied arguments as a
2909 note to be recorded with the trace run, with an effect similar to
2910 setting the variable trace-notes.
2913 The trace stop command now interprets any arguments as a note to be
2914 mentioned along with the tstatus report that the trace was stopped
2915 with a command. The effect is similar to setting the variable
2918 * Tracepoints can now be enabled and disabled at any time after a trace
2919 experiment has been started using the standard "enable" and "disable"
2920 commands. It is now possible to start a trace experiment with no enabled
2921 tracepoints; GDB will display a warning, but will allow the experiment to
2922 begin, assuming that tracepoints will be enabled as needed while the trace
2925 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2926 locations with 4-byte instructions, when they were previously
2927 limited to locations with instructions of 5 bytes or longer.
2931 set debug dwarf2-read
2932 show debug dwarf2-read
2933 Turns on or off display of debugging messages related to reading
2934 DWARF debug info. The default is off.
2936 set debug symtab-create
2937 show debug symtab-create
2938 Turns on or off display of debugging messages related to symbol table
2939 creation. The default is off.
2942 show extended-prompt
2943 Set the GDB prompt, and allow escape sequences to be inserted to
2944 display miscellaneous information (see 'help set extended-prompt'
2945 for the list of sequences). This prompt (and any information
2946 accessed through the escape sequences) is updated every time the
2947 prompt is displayed.
2949 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2950 show print entry-values
2951 Set printing of frame argument values at function entry. In some cases
2952 GDB can determine the value of function argument which was passed by the
2953 function caller, even if the value was modified inside the called function.
2955 set debug entry-values
2956 show debug entry-values
2957 Control display of debugging info for determining frame argument values at
2958 function entry and virtual tail call frames.
2960 set basenames-may-differ
2961 show basenames-may-differ
2962 Set whether a source file may have multiple base names.
2963 (A "base name" is the name of a file with the directory part removed.
2964 Example: The base name of "/home/user/hello.c" is "hello.c".)
2965 If set, GDB will canonicalize file names (e.g., expand symlinks)
2966 before comparing them. Canonicalization is an expensive operation,
2967 but it allows the same file be known by more than one base name.
2968 If not set (the default), all source files are assumed to have just
2969 one base name, and gdb will do file name comparisons more efficiently.
2975 Set a user name and notes for the current and any future trace runs.
2976 This is useful for long-running and/or disconnected traces, to
2977 inform others (or yourself) as to who is running the trace, supply
2978 contact information, or otherwise explain what is going on.
2980 set trace-stop-notes
2981 show trace-stop-notes
2982 Set a note attached to the trace run, that is displayed when the
2983 trace has been stopped by a tstop command. This is useful for
2984 instance as an explanation, if you are stopping a trace run that was
2985 started by someone else.
2987 * New remote packets
2991 Dynamically enable a tracepoint in a started trace experiment.
2995 Dynamically disable a tracepoint in a started trace experiment.
2999 Set the user and notes of the trace run.
3003 Query the current status of a tracepoint.
3007 Query the minimum length of instruction at which a fast tracepoint may
3010 * Dcache size (number of lines) and line-size are now runtime-configurable
3011 via "set dcache line" and "set dcache line-size" commands.
3015 Texas Instruments TMS320C6x tic6x-*-*
3019 Renesas RL78 rl78-*-elf
3021 *** Changes in GDB 7.3.1
3023 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3025 *** Changes in GDB 7.3
3027 * GDB has a new command: "thread find [REGEXP]".
3028 It finds the thread id whose name, target id, or thread extra info
3029 matches the given regular expression.
3031 * The "catch syscall" command now works on mips*-linux* targets.
3033 * The -data-disassemble MI command now supports modes 2 and 3 for
3034 dumping the instruction opcodes.
3036 * New command line options
3038 -data-directory DIR Specify DIR as the "data-directory".
3039 This is mostly for testing purposes.
3041 * The "maint set python auto-load on|off" command has been renamed to
3042 "set auto-load-scripts on|off".
3044 * GDB has a new command: "set directories".
3045 It is like the "dir" command except that it replaces the
3046 source path list instead of augmenting it.
3048 * GDB now understands thread names.
3050 On GNU/Linux, "info threads" will display the thread name as set by
3051 prctl or pthread_setname_np.
3053 There is also a new command, "thread name", which can be used to
3054 assign a name internally for GDB to display.
3057 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3058 has been integrated into GDB.
3062 ** The function gdb.Write now accepts an optional keyword 'stream'.
3063 This keyword, when provided, will direct the output to either
3064 stdout, stderr, or GDB's logging output.
3066 ** Parameters can now be be sub-classed in Python, and in particular
3067 you may implement the get_set_doc and get_show_doc functions.
3068 This improves how Parameter set/show documentation is processed
3069 and allows for more dynamic content.
3071 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3072 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3073 have an is_valid method.
3075 ** Breakpoints can now be sub-classed in Python, and in particular
3076 you may implement a 'stop' function that is executed each time
3077 the inferior reaches that breakpoint.
3079 ** New function gdb.lookup_global_symbol looks up a global symbol.
3081 ** GDB values in Python are now callable if the value represents a
3082 function. For example, if 'some_value' represents a function that
3083 takes two integer parameters and returns a value, you can call
3084 that function like so:
3086 result = some_value (10,20)
3088 ** Module gdb.types has been added.
3089 It contains a collection of utilities for working with gdb.Types objects:
3090 get_basic_type, has_field, make_enum_dict.
3092 ** Module gdb.printing has been added.
3093 It contains utilities for writing and registering pretty-printers.
3094 New classes: PrettyPrinter, SubPrettyPrinter,
3095 RegexpCollectionPrettyPrinter.
3096 New function: register_pretty_printer.
3098 ** New commands "info pretty-printers", "enable pretty-printer" and
3099 "disable pretty-printer" have been added.
3101 ** gdb.parameter("directories") is now available.
3103 ** New function gdb.newest_frame returns the newest frame in the
3106 ** The gdb.InferiorThread class has a new "name" attribute. This
3107 holds the thread's name.
3109 ** Python Support for Inferior events.
3110 Python scripts can add observers to be notified of events
3111 occurring in the process being debugged.
3112 The following events are currently supported:
3113 - gdb.events.cont Continue event.
3114 - gdb.events.exited Inferior exited event.
3115 - gdb.events.stop Signal received, and Breakpoint hit events.
3119 ** GDB now puts template parameters in scope when debugging in an
3120 instantiation. For example, if you have:
3122 template<int X> int func (void) { return X; }
3124 then if you step into func<5>, "print X" will show "5". This
3125 feature requires proper debuginfo support from the compiler; it
3126 was added to GCC 4.5.
3128 ** The motion commands "next", "finish", "until", and "advance" now
3129 work better when exceptions are thrown. In particular, GDB will
3130 no longer lose control of the inferior; instead, the GDB will
3131 stop the inferior at the point at which the exception is caught.
3132 This functionality requires a change in the exception handling
3133 code that was introduced in GCC 4.5.
3135 * GDB now follows GCC's rules on accessing volatile objects when
3136 reading or writing target state during expression evaluation.
3137 One notable difference to prior behavior is that "print x = 0"
3138 no longer generates a read of x; the value of the assignment is
3139 now always taken directly from the value being assigned.
3141 * GDB now has some support for using labels in the program's source in
3142 linespecs. For instance, you can use "advance label" to continue
3143 execution to a label.
3145 * GDB now has support for reading and writing a new .gdb_index
3146 section. This section holds a fast index of DWARF debugging
3147 information and can be used to greatly speed up GDB startup and
3148 operation. See the documentation for `save gdb-index' for details.
3150 * The "watch" command now accepts an optional "-location" argument.
3151 When used, this causes GDB to watch the memory referred to by the
3152 expression. Such a watchpoint is never deleted due to it going out
3155 * GDB now supports thread debugging of core dumps on GNU/Linux.
3157 GDB now activates thread debugging using the libthread_db library
3158 when debugging GNU/Linux core dumps, similarly to when debugging
3159 live processes. As a result, when debugging a core dump file, GDB
3160 is now able to display pthread_t ids of threads. For example, "info
3161 threads" shows the same output as when debugging the process when it
3162 was live. In earlier releases, you'd see something like this:
3165 * 1 LWP 6780 main () at main.c:10
3167 While now you see this:
3170 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3172 It is also now possible to inspect TLS variables when debugging core
3175 When debugging a core dump generated on a machine other than the one
3176 used to run GDB, you may need to point GDB at the correct
3177 libthread_db library with the "set libthread-db-search-path"
3178 command. See the user manual for more details on this command.
3180 * When natively debugging programs on PowerPC BookE processors running
3181 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3182 which stop execution of the inferior whenever it executes an instruction
3183 at any address within the specified range. See the "PowerPC Embedded"
3184 section in the user manual for more details.
3186 * New features in the GDB remote stub, GDBserver
3188 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3189 and i686 LynxOS (version 5.x).
3191 ** GDBserver is now supported on Blackfin Linux.
3193 * New native configurations
3195 ia64 HP-UX ia64-*-hpux*
3199 Analog Devices, Inc. Blackfin Processor bfin-*
3201 * Ada task switching is now supported on sparc-elf targets when
3202 debugging a program using the Ravenscar Profile. For more information,
3203 see the "Tasking Support when using the Ravenscar Profile" section
3204 in the GDB user manual.
3206 * Guile support was removed.
3208 * New features in the GNU simulator
3210 ** The --map-info flag lists all known core mappings.
3212 ** CFI flashes may be simulated via the "cfi" device.
3214 *** Changes in GDB 7.2
3216 * Shared library support for remote targets by default
3218 When GDB is configured for a generic, non-OS specific target, like
3219 for example, --target=arm-eabi or one of the many *-*-elf targets,
3220 GDB now queries remote stubs for loaded shared libraries using the
3221 `qXfer:libraries:read' packet. Previously, shared library support
3222 was always disabled for such configurations.
3226 ** Argument Dependent Lookup (ADL)
3228 In C++ ADL lookup directs function search to the namespaces of its
3229 arguments even if the namespace has not been imported.
3239 Here the compiler will search for `foo' in the namespace of 'b'
3240 and find A::foo. GDB now supports this. This construct is commonly
3241 used in the Standard Template Library for operators.
3243 ** Improved User Defined Operator Support
3245 In addition to member operators, GDB now supports lookup of operators
3246 defined in a namespace and imported with a `using' directive, operators
3247 defined in the global scope, operators imported implicitly from an
3248 anonymous namespace, and the ADL operators mentioned in the previous
3250 GDB now also supports proper overload resolution for all the previously
3251 mentioned flavors of operators.
3253 ** static const class members
3255 Printing of static const class members that are initialized in the
3256 class definition has been fixed.
3258 * Windows Thread Information Block access.
3260 On Windows targets, GDB now supports displaying the Windows Thread
3261 Information Block (TIB) structure. This structure is visible either
3262 by using the new command `info w32 thread-information-block' or, by
3263 dereferencing the new convenience variable named `$_tlb', a
3264 thread-specific pointer to the TIB. This feature is also supported
3265 when remote debugging using GDBserver.
3267 * Static tracepoints
3269 Static tracepoints are calls in the user program into a tracing
3270 library. One such library is a port of the LTTng kernel tracer to
3271 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3272 When debugging with GDBserver, GDB now supports combining the GDB
3273 tracepoint machinery with such libraries. For example: the user can
3274 use GDB to probe a static tracepoint marker (a call from the user
3275 program into the tracing library) with the new "strace" command (see
3276 "New commands" below). This creates a "static tracepoint" in the
3277 breakpoint list, that can be manipulated with the same feature set
3278 as fast and regular tracepoints. E.g., collect registers, local and
3279 global variables, collect trace state variables, and define
3280 tracepoint conditions. In addition, the user can collect extra
3281 static tracepoint marker specific data, by collecting the new
3282 $_sdata internal variable. When analyzing the trace buffer, you can
3283 inspect $_sdata like any other variable available to GDB. For more
3284 information, see the "Tracepoints" chapter in GDB user manual. New
3285 remote packets have been defined to support static tracepoints, see
3286 the "New remote packets" section below.
3288 * Better reconstruction of tracepoints after disconnected tracing
3290 GDB will attempt to download the original source form of tracepoint
3291 definitions when starting a trace run, and then will upload these
3292 upon reconnection to the target, resulting in a more accurate
3293 reconstruction of the tracepoints that are in use on the target.
3297 You can now exercise direct control over the ways that GDB can
3298 affect your program. For instance, you can disallow the setting of
3299 breakpoints, so that the program can run continuously (assuming
3300 non-stop mode). In addition, the "observer" variable is available
3301 to switch all of the different controls; in observer mode, GDB
3302 cannot affect the target's behavior at all, which is useful for
3303 tasks like diagnosing live systems in the field.
3305 * The new convenience variable $_thread holds the number of the
3308 * New remote packets
3312 Return the address of the Windows Thread Information Block of a given thread.
3316 In response to several of the tracepoint packets, the target may now
3317 also respond with a number of intermediate `qRelocInsn' request
3318 packets before the final result packet, to have GDB handle
3319 relocating an instruction to execute at a different address. This
3320 is particularly useful for stubs that support fast tracepoints. GDB
3321 reports support for this feature in the qSupported packet.
3325 List static tracepoint markers in the target program.
3329 List static tracepoint markers at a given address in the target
3332 qXfer:statictrace:read
3334 Read the static trace data collected (by a `collect $_sdata'
3335 tracepoint action). The remote stub reports support for this packet
3336 to gdb's qSupported query.
3340 Send the current settings of GDB's permission flags.
3344 Send part of the source (textual) form of a tracepoint definition,
3345 which includes location, conditional, and action list.
3347 * The source command now accepts a -s option to force searching for the
3348 script in the source search path even if the script name specifies
3351 * New features in the GDB remote stub, GDBserver
3353 - GDBserver now support tracepoints (including fast tracepoints, and
3354 static tracepoints). The feature is currently supported by the
3355 i386-linux and amd64-linux builds. See the "Tracepoints support
3356 in gdbserver" section in the manual for more information.
3358 GDBserver JIT compiles the tracepoint's conditional agent
3359 expression bytecode into native code whenever possible for low
3360 overhead dynamic tracepoints conditionals. For such tracepoints,
3361 an expression that examines program state is evaluated when the
3362 tracepoint is reached, in order to determine whether to capture
3363 trace data. If the condition is simple and false, processing the
3364 tracepoint finishes very quickly and no data is gathered.
3366 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3367 for static tracepoints support.
3369 - GDBserver now supports x86_64 Windows 64-bit debugging.
3371 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3372 it understands register description.
3374 * The --batch flag now disables pagination and queries.
3376 * X86 general purpose registers
3378 GDB now supports reading/writing byte, word and double-word x86
3379 general purpose registers directly. This means you can use, say,
3380 $ah or $ax to refer, respectively, to the byte register AH and
3381 16-bit word register AX that are actually portions of the 32-bit
3382 register EAX or 64-bit register RAX.
3384 * The `commands' command now accepts a range of breakpoints to modify.
3385 A plain `commands' following a command that creates multiple
3386 breakpoints affects all the breakpoints set by that command. This
3387 applies to breakpoints set by `rbreak', and also applies when a
3388 single `break' command creates multiple breakpoints (e.g.,
3389 breakpoints on overloaded c++ functions).
3391 * The `rbreak' command now accepts a filename specification as part of
3392 its argument, limiting the functions selected by the regex to those
3393 in the specified file.
3395 * Support for remote debugging Windows and SymbianOS shared libraries
3396 from Unix hosts has been improved. Non Windows GDB builds now can
3397 understand target reported file names that follow MS-DOS based file
3398 system semantics, such as file names that include drive letters and
3399 use the backslash character as directory separator. This makes it
3400 possible to transparently use the "set sysroot" and "set
3401 solib-search-path" on Unix hosts to point as host copies of the
3402 target's shared libraries. See the new command "set
3403 target-file-system-kind" described below, and the "Commands to
3404 specify files" section in the user manual for more information.
3408 eval template, expressions...
3409 Convert the values of one or more expressions under the control
3410 of the string template to a command line, and call it.
3412 set target-file-system-kind unix|dos-based|auto
3413 show target-file-system-kind
3414 Set or show the assumed file system kind for target reported file
3417 save breakpoints <filename>
3418 Save all current breakpoint definitions to a file suitable for use
3419 in a later debugging session. To read the saved breakpoint
3420 definitions, use the `source' command.
3422 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3425 info static-tracepoint-markers
3426 Display information about static tracepoint markers in the target.
3428 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3429 Define a static tracepoint by probing a marker at the given
3430 function, line, address, or marker ID.
3434 Enable and disable observer mode.
3436 set may-write-registers on|off
3437 set may-write-memory on|off
3438 set may-insert-breakpoints on|off
3439 set may-insert-tracepoints on|off
3440 set may-insert-fast-tracepoints on|off
3441 set may-interrupt on|off
3442 Set individual permissions for GDB effects on the target. Note that
3443 some of these settings can have undesirable or surprising
3444 consequences, particularly when changed in the middle of a session.
3445 For instance, disabling the writing of memory can prevent
3446 breakpoints from being inserted, cause single-stepping to fail, or
3447 even crash your program, if you disable after breakpoints have been
3448 inserted. However, GDB should not crash.
3450 set record memory-query on|off
3451 show record memory-query
3452 Control whether to stop the inferior if memory changes caused
3453 by an instruction cannot be recorded.
3458 The disassemble command now supports "start,+length" form of two arguments.
3462 ** GDB now provides a new directory location, called the python directory,
3463 where Python scripts written for GDB can be installed. The location
3464 of that directory is <data-directory>/python, where <data-directory>
3465 is the GDB data directory. For more details, see section `Scripting
3466 GDB using Python' in the manual.
3468 ** The GDB Python API now has access to breakpoints, symbols, symbol
3469 tables, program spaces, inferiors, threads and frame's code blocks.
3470 Additionally, GDB Parameters can now be created from the API, and
3471 manipulated via set/show in the CLI.
3473 ** New functions gdb.target_charset, gdb.target_wide_charset,
3474 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3476 ** New exception gdb.GdbError.
3478 ** Pretty-printers are now also looked up in the current program space.
3480 ** Pretty-printers can now be individually enabled and disabled.
3482 ** GDB now looks for names of Python scripts to auto-load in a
3483 special section named `.debug_gdb_scripts', in addition to looking
3484 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3486 * Tracepoint actions were unified with breakpoint commands. In particular,
3487 there are no longer differences in "info break" output for breakpoints and
3488 tracepoints and the "commands" command can be used for both tracepoints and
3489 regular breakpoints.
3493 ARM Symbian arm*-*-symbianelf*
3495 * D language support.
3496 GDB now supports debugging programs written in the D programming
3499 * GDB now supports the extended ptrace interface for PowerPC which is
3500 available since Linux kernel version 2.6.34. This automatically enables
3501 any hardware breakpoints and additional hardware watchpoints available in
3502 the processor. The old ptrace interface exposes just one hardware
3503 watchpoint and no hardware breakpoints.
3505 * GDB is now able to use the Data Value Compare (DVC) register available on
3506 embedded PowerPC processors to implement in hardware simple watchpoint
3507 conditions of the form:
3509 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3511 This works in native GDB running on Linux kernels with the extended ptrace
3512 interface mentioned above.
3514 *** Changes in GDB 7.1
3518 ** Namespace Support
3520 GDB now supports importing of namespaces in C++. This enables the
3521 user to inspect variables from imported namespaces. Support for
3522 namepace aliasing has also been added. So, if a namespace is
3523 aliased in the current scope (e.g. namepace C=A; ) the user can
3524 print variables using the alias (e.g. (gdb) print C::x).
3528 All known bugs relating to the printing of virtual base class were
3529 fixed. It is now possible to call overloaded static methods using a
3534 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3535 and reinterpret_cast<> are now handled by the C++ expression parser.
3539 Xilinx MicroBlaze microblaze-*-*
3544 Xilinx MicroBlaze microblaze
3547 * Multi-program debugging.
3549 GDB now has support for multi-program (a.k.a. multi-executable or
3550 multi-exec) debugging. This allows for debugging multiple inferiors
3551 simultaneously each running a different program under the same GDB
3552 session. See "Debugging Multiple Inferiors and Programs" in the
3553 manual for more information. This implied some user visible changes
3554 in the multi-inferior support. For example, "info inferiors" now
3555 lists inferiors that are not running yet or that have exited
3556 already. See also "New commands" and "New options" below.
3558 * New tracing features
3560 GDB's tracepoint facility now includes several new features:
3562 ** Trace state variables
3564 GDB tracepoints now include support for trace state variables, which
3565 are variables managed by the target agent during a tracing
3566 experiment. They are useful for tracepoints that trigger each
3567 other, so for instance one tracepoint can count hits in a variable,
3568 and then a second tracepoint has a condition that is true when the
3569 count reaches a particular value. Trace state variables share the
3570 $-syntax of GDB convenience variables, and can appear in both
3571 tracepoint actions and condition expressions. Use the "tvariable"
3572 command to create, and "info tvariables" to view; see "Trace State
3573 Variables" in the manual for more detail.
3577 GDB now includes an option for defining fast tracepoints, which
3578 targets may implement more efficiently, such as by installing a jump
3579 into the target agent rather than a trap instruction. The resulting
3580 speedup can be by two orders of magnitude or more, although the
3581 tradeoff is that some program locations on some target architectures
3582 might not allow fast tracepoint installation, for instance if the
3583 instruction to be replaced is shorter than the jump. To request a
3584 fast tracepoint, use the "ftrace" command, with syntax identical to
3585 the regular trace command.
3587 ** Disconnected tracing
3589 It is now possible to detach GDB from the target while it is running
3590 a trace experiment, then reconnect later to see how the experiment
3591 is going. In addition, a new variable disconnected-tracing lets you
3592 tell the target agent whether to continue running a trace if the
3593 connection is lost unexpectedly.
3597 GDB now has the ability to save the trace buffer into a file, and
3598 then use that file as a target, similarly to you can do with
3599 corefiles. You can select trace frames, print data that was
3600 collected in them, and use tstatus to display the state of the
3601 tracing run at the moment that it was saved. To create a trace
3602 file, use "tsave <filename>", and to use it, do "target tfile
3605 ** Circular trace buffer
3607 You can ask the target agent to handle the trace buffer as a
3608 circular buffer, discarding the oldest trace frames to make room for
3609 newer ones, by setting circular-trace-buffer to on. This feature may
3610 not be available for all target agents.
3615 The disassemble command, when invoked with two arguments, now requires
3616 the arguments to be comma-separated.
3619 The info variables command now displays variable definitions. Files
3620 which only declare a variable are not shown.
3623 The source command is now capable of sourcing Python scripts.
3624 This feature is dependent on the debugger being build with Python
3627 Related to this enhancement is also the introduction of a new command
3628 "set script-extension" (see below).
3630 * New commands (for set/show, see "New options" below)
3632 record save [<FILENAME>]
3633 Save a file (in core file format) containing the process record
3634 execution log for replay debugging at a later time.
3636 record restore <FILENAME>
3637 Restore the process record execution log that was saved at an
3638 earlier time, for replay debugging.
3640 add-inferior [-copies <N>] [-exec <FILENAME>]
3643 clone-inferior [-copies <N>] [ID]
3644 Make a new inferior ready to execute the same program another
3645 inferior has loaded.
3650 maint info program-spaces
3651 List the program spaces loaded into GDB.
3653 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3654 show remote interrupt-sequence
3655 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3656 as the sequence to the remote target in order to interrupt the execution.
3657 Ctrl-C is a default. Some system prefers BREAK which is high level of
3658 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3659 Magic SysRq g. It is BREAK signal and character 'g'.
3661 set remote interrupt-on-connect [on | off]
3662 show remote interrupt-on-connect
3663 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3664 remote target when gdb connects to it. This is needed when you debug
3667 set remotebreak [on | off]
3669 Deprecated. Use "set/show remote interrupt-sequence" instead.
3671 tvariable $NAME [ = EXP ]
3672 Create or modify a trace state variable.
3675 List trace state variables and their values.
3677 delete tvariable $NAME ...
3678 Delete one or more trace state variables.
3681 Evaluate the given expressions without collecting anything into the
3682 trace buffer. (Valid in tracepoint actions only.)
3684 ftrace FN / FILE:LINE / *ADDR
3685 Define a fast tracepoint at the given function, line, or address.
3687 * New expression syntax
3689 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3690 GDB now parses 0b101010 identically with 42.
3694 set follow-exec-mode new|same
3695 show follow-exec-mode
3696 Control whether GDB reuses the same inferior across an exec call or
3697 creates a new one. This is useful to be able to restart the old
3698 executable after the inferior having done an exec call.
3700 set default-collect EXPR, ...
3701 show default-collect
3702 Define a list of expressions to be collected at each tracepoint.
3703 This is a useful way to ensure essential items are not overlooked,
3704 such as registers or a critical global variable.
3706 set disconnected-tracing
3707 show disconnected-tracing
3708 If set to 1, the target is instructed to continue tracing if it
3709 loses its connection to GDB. If 0, the target is to stop tracing
3712 set circular-trace-buffer
3713 show circular-trace-buffer
3714 If set to on, the target is instructed to use a circular trace buffer
3715 and discard the oldest trace frames instead of stopping the trace due
3716 to a full trace buffer. If set to off, the trace stops when the buffer
3717 fills up. Some targets may not support this.
3719 set script-extension off|soft|strict
3720 show script-extension
3721 If set to "off", the debugger does not perform any script language
3722 recognition, and all sourced files are assumed to be GDB scripts.
3723 If set to "soft" (the default), files are sourced according to
3724 filename extension, falling back to GDB scripts if the first
3726 If set to "strict", files are sourced according to filename extension.
3728 set ada trust-PAD-over-XVS on|off
3729 show ada trust-PAD-over-XVS
3730 If off, activate a workaround against a bug in the debugging information
3731 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3732 the GCC sources for more information about the GNAT encoding and
3733 PAD types in particular). It is always safe to set this option to
3734 off, but this introduces a slight performance penalty. The default
3737 * Python API Improvements
3739 ** GDB provides the new class gdb.LazyString. This is useful in
3740 some pretty-printing cases. The new method gdb.Value.lazy_string
3741 provides a simple way to create objects of this type.
3743 ** The fields returned by gdb.Type.fields now have an
3744 `is_base_class' attribute.
3746 ** The new method gdb.Type.range returns the range of an array type.
3748 ** The new method gdb.parse_and_eval can be used to parse and
3749 evaluate an expression.
3751 * New remote packets
3754 Define a trace state variable.
3757 Get the current value of a trace state variable.
3760 Set desired tracing behavior upon disconnection.
3763 Set the trace buffer to be linear or circular.
3766 Get data about the tracepoints currently in use.
3770 Process record now works correctly with hardware watchpoints.
3772 Multiple bug fixes have been made to the mips-irix port, making it
3773 much more reliable. In particular:
3774 - Debugging threaded applications is now possible again. Previously,
3775 GDB would hang while starting the program, or while waiting for
3776 the program to stop at a breakpoint.
3777 - Attaching to a running process no longer hangs.
3778 - An error occurring while loading a core file has been fixed.
3779 - Changing the value of the PC register now works again. This fixes
3780 problems observed when using the "jump" command, or when calling
3781 a function from GDB, or even when assigning a new value to $pc.
3782 - With the "finish" and "return" commands, the return value for functions
3783 returning a small array is now correctly printed.
3784 - It is now possible to break on shared library code which gets executed
3785 during a shared library init phase (code executed while executing
3786 their .init section). Previously, the breakpoint would have no effect.
3787 - GDB is now able to backtrace through the signal handler for
3788 non-threaded programs.
3790 PIE (Position Independent Executable) programs debugging is now supported.
3791 This includes debugging execution of PIC (Position Independent Code) shared
3792 libraries although for that, it should be possible to run such libraries as an
3795 *** Changes in GDB 7.0
3797 * GDB now has an interface for JIT compilation. Applications that
3798 dynamically generate code can create symbol files in memory and register
3799 them with GDB. For users, the feature should work transparently, and
3800 for JIT developers, the interface is documented in the GDB manual in the
3801 "JIT Compilation Interface" chapter.
3803 * Tracepoints may now be conditional. The syntax is as for
3804 breakpoints; either an "if" clause appended to the "trace" command,
3805 or the "condition" command is available. GDB sends the condition to
3806 the target for evaluation using the same bytecode format as is used
3807 for tracepoint actions.
3809 * The disassemble command now supports: an optional /r modifier, print the
3810 raw instructions in hex as well as in symbolic form, and an optional /m
3811 modifier to print mixed source+assembly.
3813 * Process record and replay
3815 In a architecture environment that supports ``process record and
3816 replay'', ``process record and replay'' target can record a log of
3817 the process execution, and replay it with both forward and reverse
3820 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3821 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3822 set execution-direction {forward|reverse}, for targets that support
3825 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3826 feature is available with a native GDB running on kernel version
3829 * GDB now has support for multi-byte and wide character sets on the
3830 target. Strings whose character type is wchar_t, char16_t, or
3831 char32_t are now correctly printed. GDB supports wide- and unicode-
3832 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3833 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3834 `printf'. This feature requires iconv to work properly; if your
3835 system does not have a working iconv, GDB can use GNU libiconv. See
3836 the installation instructions for more information.
3838 * GDB now supports automatic retrieval of shared library files from
3839 remote targets. To use this feature, specify a system root that begins
3840 with the `remote:' prefix, either via the `set sysroot' command or via
3841 the `--with-sysroot' configure-time option.
3843 * "info sharedlibrary" now takes an optional regex of libraries to show,
3844 and it now reports if a shared library has no debugging information.
3846 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3847 now complete on file names.
3849 * When completing in expressions, gdb will attempt to limit
3850 completions to allowable structure or union fields, where appropriate.
3851 For instance, consider:
3853 # struct example { int f1; double f2; };
3854 # struct example variable;
3857 If the user types TAB at the end of this command line, the available
3858 completions will be "f1" and "f2".
3860 * Inlined functions are now supported. They show up in backtraces, and
3861 the "step", "next", and "finish" commands handle them automatically.
3863 * GDB now supports the token-splicing (##) and stringification (#)
3864 operators when expanding macros. It also supports variable-arity
3867 * GDB now supports inspecting extra signal information, exported by
3868 the new $_siginfo convenience variable. The feature is currently
3869 implemented on linux ARM, i386 and amd64.
3871 * GDB can now display the VFP floating point registers and NEON vector
3872 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3873 can provide these registers (requires Linux 2.6.30 or later). Remote
3874 and simulator targets may also provide them.
3876 * New remote packets
3879 Search memory for a sequence of bytes.
3882 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3883 operation over reliable transport links. Use of this packet is
3884 controlled by the `set remote noack-packet' command.
3887 Kill the process with the specified process ID. Use this in preference
3888 to `k' when multiprocess protocol extensions are supported.
3891 Obtains additional operating system information
3895 Read or write additional signal information.
3897 * Removed remote protocol undocumented extension
3899 An undocumented extension to the remote protocol's `S' stop reply
3900 packet that permited the stub to pass a process id was removed.
3901 Remote servers should use the `T' stop reply packet instead.
3903 * GDB now supports multiple function calling conventions according to the
3904 DWARF-2 DW_AT_calling_convention function attribute.
3906 * The SH target utilizes the aforementioned change to distinguish between gcc
3907 and Renesas calling convention. It also adds the new CLI commands
3908 `set/show sh calling-convention'.
3910 * GDB can now read compressed debug sections, as produced by GNU gold
3911 with the --compress-debug-sections=zlib flag.
3913 * 64-bit core files are now supported on AIX.
3915 * Thread switching is now supported on Tru64.
3917 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3918 which will be allocated using malloc later in program execution.
3920 * The qXfer:libraries:read remote procotol packet now allows passing a
3921 list of section offsets.
3923 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3924 conditions handling signals delivered during attach or thread creation
3925 have also been fixed.
3927 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3928 From the user's standpoint, all unqualified instances of True and False
3929 are treated as the standard definitions, regardless of context.
3931 * GDB now parses C++ symbol and type names more flexibly. For
3934 template<typename T> class C { };
3937 GDB will now correctly handle all of:
3939 ptype C<char const *>
3940 ptype C<char const*>
3941 ptype C<const char *>
3942 ptype C<const char*>
3944 * New features in the GDB remote stub, gdbserver
3946 - The "--wrapper" command-line argument tells gdbserver to use a
3947 wrapper program to launch programs for debugging.
3949 - On PowerPC and S/390 targets, it is now possible to use a single
3950 gdbserver executable to debug both 32-bit and 64-bit programs.
3951 (This requires gdbserver itself to be built as a 64-bit executable.)
3953 - gdbserver uses the new noack protocol mode for TCP connections to
3954 reduce communications latency, if also supported and enabled in GDB.
3956 - Support for the sparc64-linux-gnu target is now included in
3959 - The amd64-linux build of gdbserver now supports debugging both
3960 32-bit and 64-bit programs.
3962 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3963 now support hardware watchpoints, and will use them automatically
3968 GDB now has support for scripting using Python. Whether this is
3969 available is determined at configure time.
3971 New GDB commands can now be written in Python.
3973 * Ada tasking support
3975 Ada tasks can now be inspected in GDB. The following commands have
3979 Print the list of Ada tasks.
3981 Print detailed information about task number N.
3983 Print the task number of the current task.
3985 Switch the context of debugging to task number N.
3987 * Support for user-defined prefixed commands. The "define" command can
3988 add new commands to existing prefixes, e.g. "target".
3990 * Multi-inferior, multi-process debugging.
3992 GDB now has generalized support for multi-inferior debugging. See
3993 "Debugging Multiple Inferiors" in the manual for more information.
3994 Although availability still depends on target support, the command
3995 set is more uniform now. The GNU/Linux specific multi-forks support
3996 has been migrated to this new framework. This implied some user
3997 visible changes; see "New commands" and also "Removed commands"
4000 * Target descriptions can now describe the target OS ABI. See the
4001 "Target Description Format" section in the user manual for more
4004 * Target descriptions can now describe "compatible" architectures
4005 to indicate that the target can execute applications for a different
4006 architecture in addition to those for the main target architecture.
4007 See the "Target Description Format" section in the user manual for
4010 * Multi-architecture debugging.
4012 GDB now includes general supports for debugging applications on
4013 hybrid systems that use more than one single processor architecture
4014 at the same time. Each such hybrid architecture still requires
4015 specific support to be added. The only hybrid architecture supported
4016 in this version of GDB is the Cell Broadband Engine.
4018 * GDB now supports integrated debugging of Cell/B.E. applications that
4019 use both the PPU and SPU architectures. To enable support for hybrid
4020 Cell/B.E. debugging, you need to configure GDB to support both the
4021 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4022 --enable-targets configure option.
4024 * Non-stop mode debugging.
4026 For some targets, GDB now supports an optional mode of operation in
4027 which you can examine stopped threads while other threads continue
4028 to execute freely. This is referred to as non-stop mode, with the
4029 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4030 section in the user manual for more information.
4032 To be able to support remote non-stop debugging, a remote stub needs
4033 to implement the non-stop mode remote protocol extensions, as
4034 described in the "Remote Non-Stop" section of the user manual. The
4035 GDB remote stub, gdbserver, has been adjusted to support these
4036 extensions on linux targets.
4038 * New commands (for set/show, see "New options" below)
4040 catch syscall [NAME(S) | NUMBER(S)]
4041 Catch system calls. Arguments, which should be names of system
4042 calls or their numbers, mean catch only those syscalls. Without
4043 arguments, every syscall will be caught. When the inferior issues
4044 any of the specified syscalls, GDB will stop and announce the system
4045 call, both when it is called and when its call returns. This
4046 feature is currently available with a native GDB running on the
4047 Linux Kernel, under the following architectures: x86, x86_64,
4048 PowerPC and PowerPC64.
4050 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4052 Search memory for a sequence of bytes.
4054 maint set python print-stack
4055 maint show python print-stack
4056 Show a stack trace when an error is encountered in a Python script.
4059 Invoke CODE by passing it to the Python interpreter.
4064 These allow macros to be defined, undefined, and listed
4068 Show operating system information about processes.
4071 List the inferiors currently under GDB's control.
4074 Switch focus to inferior number NUM.
4077 Detach from inferior number NUM.
4080 Kill inferior number NUM.
4084 set spu stop-on-load
4085 show spu stop-on-load
4086 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4088 set spu auto-flush-cache
4089 show spu auto-flush-cache
4090 Control whether to automatically flush the software-managed cache
4091 during Cell/B.E. debugging.
4093 set sh calling-convention
4094 show sh calling-convention
4095 Control the calling convention used when calling SH target functions.
4098 show debug timestamp
4099 Control display of timestamps with GDB debugging output.
4101 set disassemble-next-line
4102 show disassemble-next-line
4103 Control display of disassembled source lines or instructions when
4106 set remote noack-packet
4107 show remote noack-packet
4108 Set/show the use of remote protocol QStartNoAckMode packet. See above
4109 under "New remote packets."
4111 set remote query-attached-packet
4112 show remote query-attached-packet
4113 Control use of remote protocol `qAttached' (query-attached) packet.
4115 set remote read-siginfo-object
4116 show remote read-siginfo-object
4117 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4120 set remote write-siginfo-object
4121 show remote write-siginfo-object
4122 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4125 set remote reverse-continue
4126 show remote reverse-continue
4127 Control use of remote protocol 'bc' (reverse-continue) packet.
4129 set remote reverse-step
4130 show remote reverse-step
4131 Control use of remote protocol 'bs' (reverse-step) packet.
4133 set displaced-stepping
4134 show displaced-stepping
4135 Control displaced stepping mode. Displaced stepping is a way to
4136 single-step over breakpoints without removing them from the debuggee.
4137 Also known as "out-of-line single-stepping".
4140 show debug displaced
4141 Control display of debugging info for displaced stepping.
4143 maint set internal-error
4144 maint show internal-error
4145 Control what GDB does when an internal error is detected.
4147 maint set internal-warning
4148 maint show internal-warning
4149 Control what GDB does when an internal warning is detected.
4154 Use a wrapper program to launch programs for debugging.
4156 set multiple-symbols (all|ask|cancel)
4157 show multiple-symbols
4158 The value of this variable can be changed to adjust the debugger behavior
4159 when an expression or a breakpoint location contains an ambiguous symbol
4160 name (an overloaded function name, for instance).
4162 set breakpoint always-inserted
4163 show breakpoint always-inserted
4164 Keep breakpoints always inserted in the target, as opposed to inserting
4165 them when resuming the target, and removing them when the target stops.
4166 This option can improve debugger performance on slow remote targets.
4168 set arm fallback-mode (arm|thumb|auto)
4169 show arm fallback-mode
4170 set arm force-mode (arm|thumb|auto)
4172 These commands control how ARM GDB determines whether instructions
4173 are ARM or Thumb. The default for both settings is auto, which uses
4174 the current CPSR value for instructions without symbols; previous
4175 versions of GDB behaved as if "set arm fallback-mode arm".
4177 set disable-randomization
4178 show disable-randomization
4179 Standalone programs run with the virtual address space randomization enabled
4180 by default on some platforms. This option keeps the addresses stable across
4181 multiple debugging sessions.
4185 Control whether other threads are stopped or not when some thread hits
4190 Requests that asynchronous execution is enabled in the target, if available.
4191 In this case, it's possible to resume target in the background, and interact
4192 with GDB while the target is running. "show target-async" displays the
4193 current state of asynchronous execution of the target.
4195 set target-wide-charset
4196 show target-wide-charset
4197 The target-wide-charset is the name of the character set that GDB
4198 uses when printing characters whose type is wchar_t.
4200 set tcp auto-retry (on|off)
4202 set tcp connect-timeout
4203 show tcp connect-timeout
4204 These commands allow GDB to retry failed TCP connections to a remote stub
4205 with a specified timeout period; this is useful if the stub is launched
4206 in parallel with GDB but may not be ready to accept connections immediately.
4208 set libthread-db-search-path
4209 show libthread-db-search-path
4210 Control list of directories which GDB will search for appropriate
4213 set schedule-multiple (on|off)
4214 show schedule-multiple
4215 Allow GDB to resume all threads of all processes or only threads of
4216 the current process.
4220 Use more aggressive caching for accesses to the stack. This improves
4221 performance of remote debugging (particularly backtraces) without
4222 affecting correctness.
4224 set interactive-mode (on|off|auto)
4225 show interactive-mode
4226 Control whether GDB runs in interactive mode (on) or not (off).
4227 When in interactive mode, GDB waits for the user to answer all
4228 queries. Otherwise, GDB does not wait and assumes the default
4229 answer. When set to auto (the default), GDB determines which
4230 mode to use based on the stdin settings.
4235 For program forks, this is replaced by the new more generic `info
4236 inferiors' command. To list checkpoints, you can still use the
4237 `info checkpoints' command, which was an alias for the `info forks'
4241 Replaced by the new `inferior' command. To switch between
4242 checkpoints, you can still use the `restart' command, which was an
4243 alias for the `fork' command.
4246 This is removed, since some targets don't have a notion of
4247 processes. To switch between processes, you can still use the
4248 `inferior' command using GDB's own inferior number.
4251 For program forks, this is replaced by the new more generic `kill
4252 inferior' command. To delete a checkpoint, you can still use the
4253 `delete checkpoint' command, which was an alias for the `delete
4257 For program forks, this is replaced by the new more generic `detach
4258 inferior' command. To detach a checkpoint, you can still use the
4259 `detach checkpoint' command, which was an alias for the `detach
4262 * New native configurations
4264 x86/x86_64 Darwin i[34567]86-*-darwin*
4266 x86_64 MinGW x86_64-*-mingw*
4270 Lattice Mico32 lm32-*
4271 x86 DICOS i[34567]86-*-dicos*
4272 x86_64 DICOS x86_64-*-dicos*
4275 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4276 (mingw32ce) debugging.
4282 These commands were actually not implemented on any target.
4284 *** Changes in GDB 6.8
4286 * New native configurations
4288 NetBSD/hppa hppa*-*netbsd*
4289 Xtensa GNU/Linux xtensa*-*-linux*
4293 NetBSD/hppa hppa*-*-netbsd*
4294 Xtensa GNU/Lunux xtensa*-*-linux*
4296 * Change in command line behavior -- corefiles vs. process ids.
4298 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4299 attaching to process NUMBER fails, GDB no longer attempts to open a
4300 core file named NUMBER. Attaching to a program using the -c option
4301 is no longer supported. Instead, use the '-p' or '--pid' options.
4303 * GDB can now be built as a native debugger for debugging Windows x86
4304 (mingw32) Portable Executable (PE) programs.
4306 * Pending breakpoints no longer change their number when their address
4309 * GDB now supports breakpoints with multiple locations,
4310 including breakpoints on C++ constructors, inside C++ templates,
4311 and in inlined functions.
4313 * GDB's ability to debug optimized code has been improved. GDB more
4314 accurately identifies function bodies and lexical blocks that occupy
4315 more than one contiguous range of addresses.
4317 * Target descriptions can now describe registers for PowerPC.
4319 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4320 registers on PowerPC targets.
4322 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4323 targets even when the libthread_db library is not available.
4325 * The GDB remote stub, gdbserver, now supports the new file transfer
4326 commands (remote put, remote get, and remote delete).
4328 * The GDB remote stub, gdbserver, now supports run and attach in
4329 extended-remote mode.
4331 * hppa*64*-*-hpux11* target broken
4332 The debugger is unable to start a program and fails with the following
4333 error: "Error trying to get information about dynamic linker".
4334 The gdb-6.7 release is also affected.
4336 * GDB now supports the --enable-targets= configure option to allow
4337 building a single GDB executable that supports multiple remote
4338 target architectures.
4340 * GDB now supports debugging C and C++ programs which use the
4341 Decimal Floating Point extension. In addition, the PowerPC target
4342 now has a set of pseudo-registers to inspect decimal float values
4343 stored in two consecutive float registers.
4345 * The -break-insert MI command can optionally create pending
4348 * Improved support for debugging Ada
4349 Many improvements to the Ada language support have been made. These
4351 - Better support for Ada2005 interface types
4352 - Improved handling of arrays and slices in general
4353 - Better support for Taft-amendment types
4354 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4356 - Improved command completion in Ada
4359 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4364 set print frame-arguments (all|scalars|none)
4365 show print frame-arguments
4366 The value of this variable can be changed to control which argument
4367 values should be printed by the debugger when displaying a frame.
4372 Transfer files to and from a remote target, and delete remote files.
4379 Transfer files to and from a remote target, and delete remote files.
4381 * New remote packets
4388 Open, close, read, write, and delete files on the remote system.
4391 Attach to an existing process on the remote system, in extended-remote
4395 Run a new process on the remote system, in extended-remote mode.
4397 *** Changes in GDB 6.7
4399 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4400 bfd, libiberty and opcodes, as revealed by static analysis donated by
4401 Coverity, Inc. (http://scan.coverity.com).
4403 * When looking up multiply-defined global symbols, GDB will now prefer the
4404 symbol definition in the current shared library if it was built using the
4405 -Bsymbolic linker option.
4407 * When the Text User Interface (TUI) is not configured, GDB will now
4408 recognize the -tui command-line option and print a message that the TUI
4411 * The GDB remote stub, gdbserver, now has lower overhead for high
4412 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4414 * GDB for MIPS targets now autodetects whether a remote target provides
4415 32-bit or 64-bit register values.
4417 * Support for C++ member pointers has been improved.
4419 * GDB now understands XML target descriptions, which specify the
4420 target's overall architecture. GDB can read a description from
4421 a local file or over the remote serial protocol.
4423 * Vectors of single-byte data use a new integer type which is not
4424 automatically displayed as character or string data.
4426 * The /s format now works with the print command. It displays
4427 arrays of single-byte integers and pointers to single-byte integers
4430 * Target descriptions can now describe target-specific registers,
4431 for architectures which have implemented the support (currently
4432 only ARM, M68K, and MIPS).
4434 * GDB and the GDB remote stub, gdbserver, now support the XScale
4437 * The GDB remote stub, gdbserver, has been updated to support
4438 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4439 has been rewritten to use the standard GDB remote protocol.
4441 * GDB can now step into C++ functions which are called through thunks.
4443 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4445 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4446 layout. It also supports a TextSeg= and DataSeg= response when only
4447 segment base addresses (rather than offsets) are available.
4449 * The /i format now outputs any trailing branch delay slot instructions
4450 immediately following the last instruction within the count specified.
4452 * The GDB remote protocol "T" stop reply packet now supports a
4453 "library" response. Combined with the new "qXfer:libraries:read"
4454 packet, this response allows GDB to debug shared libraries on targets
4455 where the operating system manages the list of loaded libraries (e.g.
4456 Windows and SymbianOS).
4458 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4459 (DLLs) on Windows and Windows CE targets.
4461 * GDB now supports a faster verification that a .debug file matches its binary
4462 according to its build-id signature, if the signature is present.
4468 Enable or disable hardware flow control (RTS/CTS) on the serial port
4469 when debugging using remote targets.
4471 set mem inaccessible-by-default
4472 show mem inaccessible-by-default
4473 If the target supplies a memory map, for instance via the remote
4474 protocol's "qXfer:memory-map:read" packet, setting this variable
4475 prevents GDB from accessing memory outside the memory map. This
4476 is useful for targets with memory mapped registers or which react
4477 badly to accesses of unmapped address space.
4479 set breakpoint auto-hw
4480 show breakpoint auto-hw
4481 If the target supplies a memory map, for instance via the remote
4482 protocol's "qXfer:memory-map:read" packet, setting this variable
4483 lets GDB use hardware breakpoints automatically for memory regions
4484 where it can not use software breakpoints. This covers both the
4485 "break" command and internal breakpoints used for other commands
4486 including "next" and "finish".
4489 catch exception unhandled
4490 Stop the program execution when Ada exceptions are raised.
4493 Stop the program execution when an Ada assertion failed.
4497 Set an alternate system root for target files. This is a more
4498 general version of "set solib-absolute-prefix", which is now
4499 an alias to "set sysroot".
4502 Provide extended SPU facility status information. This set of
4503 commands is available only when debugging the Cell/B.E. SPU
4506 * New native configurations
4508 OpenBSD/sh sh*-*openbsd*
4511 unset tdesc filename
4513 Use the specified local file as an XML target description, and do
4514 not query the target for its built-in description.
4518 OpenBSD/sh sh*-*-openbsd*
4519 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4520 Toshiba Media Processor mep-elf
4522 * New remote packets
4525 Ignore the specified signals; pass them directly to the debugged program
4526 without stopping other threads or reporting them to GDB.
4528 qXfer:features:read:
4529 Read an XML target description from the target, which describes its
4534 Read or write contents of an spufs file on the target system. These
4535 packets are available only on the Cell/B.E. SPU architecture.
4537 qXfer:libraries:read:
4538 Report the loaded shared libraries. Combined with new "T" packet
4539 response, this packet allows GDB to debug shared libraries on
4540 targets where the operating system manages the list of loaded
4541 libraries (e.g. Windows and SymbianOS).
4545 Support for these obsolete configurations has been removed.
4553 i[34567]86-*-lynxos*
4554 i[34567]86-*-netware*
4555 i[34567]86-*-sco3.2v5*
4556 i[34567]86-*-sco3.2v4*
4558 i[34567]86-*-sysv4.2*
4561 i[34567]86-*-unixware2*
4562 i[34567]86-*-unixware*
4571 * Other removed features
4578 Various m68k-only ROM monitors.
4585 Various Renesas ROM monitors and debugging interfaces for SH and
4590 Support for a Macraigor serial interface to on-chip debugging.
4591 GDB does not directly support the newer parallel or USB
4596 A debug information format. The predecessor to DWARF 2 and
4597 DWARF 3, which are still supported.
4599 Support for the HP aCC compiler on HP-UX/PA-RISC
4601 SOM-encapsulated symbolic debugging information, automatic
4602 invocation of pxdb, and the aCC custom C++ ABI. This does not
4603 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4604 with aCC can still be debugged on an assembly level.
4606 MIPS ".pdr" sections
4608 A MIPS-specific format used to describe stack frame layout
4609 in debugging information.
4613 GDB could work with an older version of Guile to debug
4614 the interpreter and Scheme programs running in it.
4616 set mips stack-arg-size
4617 set mips saved-gpreg-size
4619 Use "set mips abi" to control parameter passing for MIPS.
4621 *** Changes in GDB 6.6
4626 Cell Broadband Engine SPU spu-elf
4628 * GDB can now be configured as a cross-debugger targeting native Windows
4629 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4630 running on a Windows system over TCP/IP to debug Windows programs.
4632 * The GDB remote stub, gdbserver, has been updated to support Windows and
4633 Cygwin debugging. Both single-threaded and multi-threaded programs are
4636 * The "set trust-readonly-sections" command works again. This command was
4637 broken in GDB 6.3, 6.4, and 6.5.
4639 * The "load" command now supports writing to flash memory, if the remote
4640 stub provides the required support.
4642 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4643 longer requires symbolic debug information (e.g. DWARF-2).
4648 unset substitute-path
4649 show substitute-path
4650 Manage a list of substitution rules that GDB uses to rewrite the name
4651 of the directories where the sources are located. This can be useful
4652 for instance when the sources were moved to a different location
4653 between compilation and debugging.
4657 Print each CLI command as it is executed. Each command is prefixed with
4658 a number of `+' symbols representing the nesting depth.
4659 The source command now has a `-v' option to enable the same feature.
4663 The ARM Demon monitor support (RDP protocol, "target rdp").
4665 Kernel Object Display, an embedded debugging feature which only worked with
4666 an obsolete version of Cisco IOS.
4668 The 'set download-write-size' and 'show download-write-size' commands.
4670 * New remote packets
4673 Tell a stub about GDB client features, and request remote target features.
4674 The first feature implemented is PacketSize, which allows the target to
4675 specify the size of packets it can handle - to minimize the number of
4676 packets required and improve performance when connected to a remote
4680 Fetch an OS auxilliary vector from the remote stub. This packet is a
4681 more efficient replacement for qPart:auxv:read.
4683 qXfer:memory-map:read:
4684 Fetch a memory map from the remote stub, including information about
4685 RAM, ROM, and flash memory devices.
4690 Erase and program a flash memory device.
4692 * Removed remote packets
4695 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4696 used it, and only gdbserver implemented it.
4698 *** Changes in GDB 6.5
4702 Renesas M32C/M16C m32c-elf
4704 Morpho Technologies ms1 ms1-elf
4708 init-if-undefined Initialize a convenience variable, but
4709 only if it doesn't already have a value.
4711 The following commands are presently only implemented for native GNU/Linux:
4713 checkpoint Save a snapshot of the program state.
4715 restart <n> Return the program state to a
4716 previously saved state.
4718 info checkpoints List currently saved checkpoints.
4720 delete-checkpoint <n> Delete a previously saved checkpoint.
4722 set|show detach-on-fork Tell gdb whether to detach from a newly
4723 forked process, or to keep debugging it.
4725 info forks List forks of the user program that
4726 are available to be debugged.
4728 fork <n> Switch to debugging one of several
4729 forks of the user program that are
4730 available to be debugged.
4732 delete-fork <n> Delete a fork from the list of forks
4733 that are available to be debugged (and
4734 kill the forked process).
4736 detach-fork <n> Delete a fork from the list of forks
4737 that are available to be debugged (and
4738 allow the process to continue).
4742 Morpho Technologies ms2 ms1-elf
4744 * Improved Windows host support
4746 GDB now builds as a cross debugger hosted on i686-mingw32, including
4747 native console support, and remote communications using either
4748 network sockets or serial ports.
4750 * Improved Modula-2 language support
4752 GDB can now print most types in the Modula-2 syntax. This includes:
4753 basic types, set types, record types, enumerated types, range types,
4754 pointer types and ARRAY types. Procedure var parameters are correctly
4755 printed and hexadecimal addresses and character constants are also
4756 written in the Modula-2 syntax. Best results can be obtained by using
4757 GNU Modula-2 together with the -gdwarf-2 command line option.
4761 The ARM rdi-share module.
4763 The Netware NLM debug server.
4765 *** Changes in GDB 6.4
4767 * New native configurations
4769 OpenBSD/arm arm*-*-openbsd*
4770 OpenBSD/mips64 mips64-*-openbsd*
4774 Morpho Technologies ms1 ms1-elf
4776 * New command line options
4778 --batch-silent As for --batch, but totally silent.
4779 --return-child-result The debugger will exist with the same value
4780 the child (debugged) program exited with.
4781 --eval-command COMMAND, -ex COMMAND
4782 Execute a single GDB CLI command. This may be
4783 specified multiple times and in conjunction
4784 with the --command (-x) option.
4786 * Deprecated commands removed
4788 The following commands, that were deprecated in 2000, have been
4792 set|show arm disassembly-flavor set|show arm disassembler
4793 othernames set arm disassembler
4794 set|show remotedebug set|show debug remote
4795 set|show archdebug set|show debug arch
4796 set|show eventdebug set|show debug event
4799 * New BSD user-level threads support
4801 It is now possible to debug programs using the user-level threads
4802 library on OpenBSD and FreeBSD. Currently supported (target)
4805 FreeBSD/amd64 x86_64-*-freebsd*
4806 FreeBSD/i386 i386-*-freebsd*
4807 OpenBSD/i386 i386-*-openbsd*
4809 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4810 are not yet supported.
4812 * New support for Matsushita MN10300 w/sim added
4813 (Work in progress). mn10300-elf.
4815 * REMOVED configurations and files
4817 VxWorks and the XDR protocol *-*-vxworks
4818 Motorola MCORE mcore-*-*
4819 National Semiconductor NS32000 ns32k-*-*
4821 * New "set print array-indexes" command
4823 After turning this setting "on", GDB prints the index of each element
4824 when displaying arrays. The default is "off" to preserve the previous
4827 * VAX floating point support
4829 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4831 * User-defined command support
4833 In addition to using $arg0..$arg9 for argument passing, it is now possible
4834 to use $argc to determine now many arguments have been passed. See the
4835 section on user-defined commands in the user manual for more information.
4837 *** Changes in GDB 6.3:
4839 * New command line option
4841 GDB now accepts -l followed by a number to set the timeout for remote
4844 * GDB works with GCC -feliminate-dwarf2-dups
4846 GDB now supports a more compact representation of DWARF-2 debug
4847 information using DW_FORM_ref_addr references. These are produced
4848 by GCC with the option -feliminate-dwarf2-dups and also by some
4849 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4850 to use -feliminate-dwarf2-dups.
4852 * Internationalization
4854 When supported by the host system, GDB will be built with
4855 internationalization (libintl). The task of marking up the sources is
4856 continued, we're looking forward to our first translation.
4860 Initial support for debugging programs compiled with the GNAT
4861 implementation of the Ada programming language has been integrated
4862 into GDB. In this release, support is limited to expression evaluation.
4864 * New native configurations
4866 GNU/Linux/m32r m32r-*-linux-gnu
4870 GDB's remote protocol now includes support for the 'p' packet. This
4871 packet is used to fetch individual registers from a remote inferior.
4873 * END-OF-LIFE registers[] compatibility module
4875 GDB's internal register infrastructure has been completely rewritten.
4876 The new infrastructure making possible the implementation of key new
4877 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4880 GDB 6.3 will be the last release to include the the registers[]
4881 compatibility module that allowed out-of-date configurations to
4882 continue to work. This change directly impacts the following
4892 powerpc bdm protocol
4894 Unless there is activity to revive these configurations, they will be
4895 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4897 * OBSOLETE configurations and files
4899 Configurations that have been declared obsolete in this release have
4900 been commented out. Unless there is activity to revive these
4901 configurations, the next release of GDB will have their sources
4902 permanently REMOVED.
4911 *** Changes in GDB 6.2.1:
4913 * MIPS `break main; run' gave an heuristic-fence-post warning
4915 When attempting to run even a simple program, a warning about
4916 heuristic-fence-post being hit would be reported. This problem has
4919 * MIPS IRIX 'long double' crashed GDB
4921 When examining a long double variable, GDB would get a segmentation
4922 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4923 IRIX long double values).
4927 A bug in the VAX stack code was causing problems with the "next"
4928 command. This problem has been fixed.
4930 *** Changes in GDB 6.2:
4932 * Fix for ``many threads''
4934 On GNU/Linux systems that use the NPTL threads library, a program
4935 rapidly creating and deleting threads would confuse GDB leading to the
4938 ptrace: No such process.
4939 thread_db_get_info: cannot get thread info: generic error
4941 This problem has been fixed.
4943 * "-async" and "-noasync" options removed.
4945 Support for the broken "-noasync" option has been removed (it caused
4948 * New ``start'' command.
4950 This command runs the program until the begining of the main procedure.
4952 * New BSD Kernel Data Access Library (libkvm) interface
4954 Using ``target kvm'' it is now possible to debug kernel core dumps and
4955 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4956 platforms. Currently supported (native-only) configurations are:
4958 FreeBSD/amd64 x86_64-*-freebsd*
4959 FreeBSD/i386 i?86-*-freebsd*
4960 NetBSD/i386 i?86-*-netbsd*
4961 NetBSD/m68k m68*-*-netbsd*
4962 NetBSD/sparc sparc-*-netbsd*
4963 OpenBSD/amd64 x86_64-*-openbsd*
4964 OpenBSD/i386 i?86-*-openbsd*
4965 OpenBSD/m68k m68*-openbsd*
4966 OpenBSD/sparc sparc-*-openbsd*
4968 * Signal trampoline code overhauled
4970 Many generic problems with GDB's signal handling code have been fixed.
4971 These include: backtraces through non-contiguous stacks; recognition
4972 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4973 call; backtrace through a signal trampoline; step into and out of
4974 signal handlers; and single-stepping in the signal trampoline.
4976 Please note that kernel bugs are a limiting factor here. These
4977 features have been shown to work on an s390 GNU/Linux system that
4978 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4980 * Cygwin support for DWARF 2 added.
4982 * New native configurations
4984 GNU/Linux/hppa hppa*-*-linux*
4985 OpenBSD/hppa hppa*-*-openbsd*
4986 OpenBSD/m68k m68*-*-openbsd*
4987 OpenBSD/m88k m88*-*-openbsd*
4988 OpenBSD/powerpc powerpc-*-openbsd*
4989 NetBSD/vax vax-*-netbsd*
4990 OpenBSD/vax vax-*-openbsd*
4992 * END-OF-LIFE frame compatibility module
4994 GDB's internal frame infrastructure has been completely rewritten.
4995 The new infrastructure making it possible to support key new features
4996 including DWARF 2 Call Frame Information. To aid in the task of
4997 migrating old configurations to this new infrastructure, a
4998 compatibility module, that allowed old configurations to continue to
4999 work, was also included.
5001 GDB 6.2 will be the last release to include this frame compatibility
5002 module. This change directly impacts the following configurations:
5012 Unless there is activity to revive these configurations, they will be
5013 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5015 * REMOVED configurations and files
5017 Sun 3, running SunOS 3 m68*-*-sunos3*
5018 Sun 3, running SunOS 4 m68*-*-sunos4*
5019 Sun 2, running SunOS 3 m68000-*-sunos3*
5020 Sun 2, running SunOS 4 m68000-*-sunos4*
5021 Motorola 680x0 running LynxOS m68*-*-lynxos*
5022 AT&T 3b1/Unix pc m68*-att-*
5023 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5024 decstation mips-dec-* mips-little-*
5025 riscos mips-*-riscos* mips-*-sysv*
5026 sonymips mips-sony-*
5027 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5029 *** Changes in GDB 6.1.1:
5031 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5033 The TUI (Text-mode User Interface) is now built as part of a default
5034 GDB configuration. It is enabled by either selecting the TUI with the
5035 command line option "-i=tui" or by running the separate "gdbtui"
5036 program. For more information on the TUI, see the manual "Debugging
5039 * Pending breakpoint support (also included in GDB 6.1)
5041 Support has been added to allow you to specify breakpoints in shared
5042 libraries that have not yet been loaded. If a breakpoint location
5043 cannot be found, and the "breakpoint pending" option is set to auto,
5044 GDB queries you if you wish to make the breakpoint pending on a future
5045 shared-library load. If and when GDB resolves the breakpoint symbol,
5046 the pending breakpoint is removed as one or more regular breakpoints
5049 Pending breakpoints are very useful for GCJ Java debugging.
5051 * Fixed ISO-C build problems
5053 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5054 non ISO-C code that stopped them being built using a more strict ISO-C
5055 compiler (e.g., IBM's C compiler).
5057 * Fixed build problem on IRIX 5
5059 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5060 wasn't able to compile compile on an IRIX 5 system.
5062 * Added execute permission to gdb/gdbserver/configure
5064 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5065 permission. This bug would cause configure to fail on a number of
5066 systems (Solaris, IRIX). Ref: server/519.
5068 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5070 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5071 has been updated to use constant array sizes.
5073 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5075 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5076 its generated DWARF Call Frame Info. This encoding was causing GDB to
5077 panic, that panic has been fixed. Ref: gdb/1628.
5079 * Fixed a problem when examining parameters in shared library code.
5081 When examining parameters in optimized shared library code generated
5082 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5083 not available''. GDB now correctly displays the variable's value.
5085 *** Changes in GDB 6.1:
5087 * Removed --with-mmalloc
5089 Support for the mmalloc memory manager has been removed, as it
5090 conflicted with the internal gdb byte cache.
5092 * Changes in AMD64 configurations
5094 The AMD64 target now includes the %cs and %ss registers. As a result
5095 the AMD64 remote protocol has changed; this affects the floating-point
5096 and SSE registers. If you rely on those registers for your debugging,
5097 you should upgrade gdbserver on the remote side.
5099 * Revised SPARC target
5101 The SPARC target has been completely revised, incorporating the
5102 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5103 support for LynxOS and SunOS 4 has been dropped. Calling functions
5104 from within GDB on operating systems with a non-executable stack
5105 (Solaris, OpenBSD) now works.
5109 GDB has a new C++ demangler which does a better job on the mangled
5110 names generated by current versions of g++. It also runs faster, so
5111 with this and other changes gdb should now start faster on large C++
5114 * DWARF 2 Location Expressions
5116 GDB support for location expressions has been extended to support function
5117 arguments and frame bases. Older versions of GDB could crash when they
5120 * C++ nested types and namespaces
5122 GDB's support for nested types and namespaces in C++ has been
5123 improved, especially if you use the DWARF 2 debugging format. (This
5124 is the default for recent versions of GCC on most platforms.)
5125 Specifically, if you have a class "Inner" defined within a class or
5126 namespace "Outer", then GDB realizes that the class's name is
5127 "Outer::Inner", not simply "Inner". This should greatly reduce the
5128 frequency of complaints about not finding RTTI symbols. In addition,
5129 if you are stopped at inside of a function defined within a namespace,
5130 GDB modifies its name lookup accordingly.
5132 * New native configurations
5134 NetBSD/amd64 x86_64-*-netbsd*
5135 OpenBSD/amd64 x86_64-*-openbsd*
5136 OpenBSD/alpha alpha*-*-openbsd*
5137 OpenBSD/sparc sparc-*-openbsd*
5138 OpenBSD/sparc64 sparc64-*-openbsd*
5140 * New debugging protocols
5142 M32R with SDI protocol m32r-*-elf*
5144 * "set prompt-escape-char" command deleted.
5146 The command "set prompt-escape-char" has been deleted. This command,
5147 and its very obscure effet on GDB's prompt, was never documented,
5148 tested, nor mentioned in the NEWS file.
5150 * OBSOLETE configurations and files
5152 Configurations that have been declared obsolete in this release have
5153 been commented out. Unless there is activity to revive these
5154 configurations, the next release of GDB will have their sources
5155 permanently REMOVED.
5157 Sun 3, running SunOS 3 m68*-*-sunos3*
5158 Sun 3, running SunOS 4 m68*-*-sunos4*
5159 Sun 2, running SunOS 3 m68000-*-sunos3*
5160 Sun 2, running SunOS 4 m68000-*-sunos4*
5161 Motorola 680x0 running LynxOS m68*-*-lynxos*
5162 AT&T 3b1/Unix pc m68*-att-*
5163 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5164 decstation mips-dec-* mips-little-*
5165 riscos mips-*-riscos* mips-*-sysv*
5166 sonymips mips-sony-*
5167 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5169 * REMOVED configurations and files
5171 SGI Irix-4.x mips-sgi-irix4 or iris4
5172 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5173 Z8000 simulator z8k-zilog-none or z8ksim
5174 Matsushita MN10200 w/simulator mn10200-*-*
5175 H8/500 simulator h8500-hitachi-hms or h8500hms
5176 HP/PA running BSD hppa*-*-bsd*
5177 HP/PA running OSF/1 hppa*-*-osf*
5178 HP/PA Pro target hppa*-*-pro*
5179 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5180 386BSD i[3456]86-*-bsd*
5181 Sequent family i[3456]86-sequent-sysv4*
5182 i[3456]86-sequent-sysv*
5183 i[3456]86-sequent-bsd*
5184 SPARC running LynxOS sparc-*-lynxos*
5185 SPARC running SunOS 4 sparc-*-sunos4*
5186 Tsqware Sparclet sparclet-*-*
5187 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5189 *** Changes in GDB 6.0:
5193 Support for debugging the Objective-C programming language has been
5194 integrated into GDB.
5196 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5198 DWARF 2's Call Frame Information makes available compiler generated
5199 information that more exactly describes the program's run-time stack.
5200 By using this information, GDB is able to provide more robust stack
5203 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5204 have been updated to use a new backtrace mechanism which includes
5205 DWARF 2 CFI support.
5209 GDB's remote protocol has been extended to include support for hosted
5210 file I/O (where the remote target uses GDB's file system). See GDB's
5211 remote protocol documentation for details.
5213 * All targets using the new architecture framework.
5215 All of GDB's targets have been updated to use the new internal
5216 architecture framework. The way is now open for future GDB releases
5217 to include cross-architecture native debugging support (i386 on amd64,
5220 * GNU/Linux's Thread Local Storage (TLS)
5222 GDB now includes support for for the GNU/Linux implementation of
5223 per-thread variables.
5225 * GNU/Linux's Native POSIX Thread Library (NPTL)
5227 GDB's thread code has been updated to work with either the new
5228 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5230 * Separate debug info.
5232 GDB, in conjunction with BINUTILS, now supports a mechanism for
5233 automatically loading debug information from a separate file. Instead
5234 of shipping full debug and non-debug versions of system libraries,
5235 system integrators can now instead ship just the stripped libraries
5236 and optional debug files.
5238 * DWARF 2 Location Expressions
5240 DWARF 2 Location Expressions allow the compiler to more completely
5241 describe the location of variables (even in optimized code) to the
5244 GDB now includes preliminary support for location expressions (support
5245 for DW_OP_piece is still missing).
5249 A number of long standing bugs that caused GDB to die while starting a
5250 Java application have been fixed. GDB's Java support is now
5251 considered "useable".
5253 * GNU/Linux support for fork, vfork, and exec.
5255 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5256 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5259 * GDB supports logging output to a file
5261 There are two new commands, "set logging" and "show logging", which can be
5262 used to capture GDB's output to a file.
5264 * The meaning of "detach" has changed for gdbserver
5266 The "detach" command will now resume the application, as documented. To
5267 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5270 * d10v, m68hc11 `regs' command deprecated
5272 The `info registers' command has been updated so that it displays the
5273 registers using a format identical to the old `regs' command.
5277 A new command, "maint set profile on/off", has been added. This command can
5278 be used to enable or disable profiling while running GDB, to profile a
5279 session or a set of commands. In addition there is a new configure switch,
5280 "--enable-profiling", which will cause GDB to be compiled with profiling
5281 data, for more informative profiling results.
5283 * Default MI syntax changed to "mi2".
5285 The default MI (machine interface) syntax, enabled by the command line
5286 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5287 "mi1", can be enabled by specifying the option "-i=mi1".
5289 Support for the original "mi0" syntax (included in GDB 5.0) has been
5292 Fix for gdb/192: removed extraneous space when displaying frame level.
5293 Fix for gdb/672: update changelist is now output in mi list format.
5294 Fix for gdb/702: a -var-assign that updates the value now shows up
5295 in a subsequent -var-update.
5297 * New native configurations.
5299 FreeBSD/amd64 x86_64-*-freebsd*
5301 * Multi-arched targets.
5303 HP/PA HPUX11 hppa*-*-hpux*
5304 Renesas M32R/D w/simulator m32r-*-elf*
5306 * OBSOLETE configurations and files
5308 Configurations that have been declared obsolete in this release have
5309 been commented out. Unless there is activity to revive these
5310 configurations, the next release of GDB will have their sources
5311 permanently REMOVED.
5313 Z8000 simulator z8k-zilog-none or z8ksim
5314 Matsushita MN10200 w/simulator mn10200-*-*
5315 H8/500 simulator h8500-hitachi-hms or h8500hms
5316 HP/PA running BSD hppa*-*-bsd*
5317 HP/PA running OSF/1 hppa*-*-osf*
5318 HP/PA Pro target hppa*-*-pro*
5319 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5320 Sequent family i[3456]86-sequent-sysv4*
5321 i[3456]86-sequent-sysv*
5322 i[3456]86-sequent-bsd*
5323 Tsqware Sparclet sparclet-*-*
5324 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5326 * REMOVED configurations and files
5329 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5330 IBM AIX PS/2 i[3456]86-*-aix
5331 i386 running Mach 3.0 i[3456]86-*-mach3*
5332 i386 running Mach i[3456]86-*-mach*
5333 i386 running OSF/1 i[3456]86-*osf1mk*
5334 HP/Apollo 68k Family m68*-apollo*-sysv*,
5336 m68*-hp-bsd*, m68*-hp-hpux*
5337 Argonaut Risc Chip (ARC) arc-*-*
5338 Mitsubishi D30V d30v-*-*
5339 Fujitsu FR30 fr30-*-elf*
5340 OS/9000 i[34]86-*-os9k
5341 I960 with MON960 i960-*-coff
5343 * MIPS $fp behavior changed
5345 The convenience variable $fp, for the MIPS, now consistently returns
5346 the address of the current frame's base. Previously, depending on the
5347 context, $fp could refer to either $sp or the current frame's base
5348 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5349 The GNU Source-Level Debugger''.
5351 *** Changes in GDB 5.3:
5353 * GNU/Linux shared library multi-threaded performance improved.
5355 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5356 `/proc', in preference to `ptrace' for memory reads. This may result
5357 in an improvement in the start-up time of multi-threaded, shared
5358 library applications when run under GDB. One GDB user writes: ``loads
5359 shared libs like mad''.
5361 * ``gdbserver'' now supports multi-threaded applications on some targets
5363 Support for debugging multi-threaded applications which use
5364 the GNU/Linux LinuxThreads package has been added for
5365 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5366 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5368 * GDB now supports C/C++ preprocessor macros.
5370 GDB now expands preprocessor macro invocations in C/C++ expressions,
5371 and provides various commands for showing macro definitions and how
5374 The new command `macro expand EXPRESSION' expands any macro
5375 invocations in expression, and shows the result.
5377 The new command `show macro MACRO-NAME' shows the definition of the
5378 macro named MACRO-NAME, and where it was defined.
5380 Most compilers don't include information about macros in the debugging
5381 information by default. In GCC 3.1, for example, you need to compile
5382 your program with the options `-gdwarf-2 -g3'. If the macro
5383 information is present in the executable, GDB will read it.
5385 * Multi-arched targets.
5387 DEC Alpha (partial) alpha*-*-*
5388 DEC VAX (partial) vax-*-*
5390 National Semiconductor NS32000 (partial) ns32k-*-*
5391 Motorola 68000 (partial) m68k-*-*
5392 Motorola MCORE mcore-*-*
5396 Fujitsu FRV architecture added by Red Hat frv*-*-*
5399 * New native configurations
5401 Alpha NetBSD alpha*-*-netbsd*
5402 SH NetBSD sh*-*-netbsdelf*
5403 MIPS NetBSD mips*-*-netbsd*
5404 UltraSPARC NetBSD sparc64-*-netbsd*
5406 * OBSOLETE configurations and files
5408 Configurations that have been declared obsolete in this release have
5409 been commented out. Unless there is activity to revive these
5410 configurations, the next release of GDB will have their sources
5411 permanently REMOVED.
5413 Mitsubishi D30V d30v-*-*
5414 OS/9000 i[34]86-*-os9k
5415 IBM AIX PS/2 i[3456]86-*-aix
5416 Fujitsu FR30 fr30-*-elf*
5417 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5418 Argonaut Risc Chip (ARC) arc-*-*
5419 i386 running Mach 3.0 i[3456]86-*-mach3*
5420 i386 running Mach i[3456]86-*-mach*
5421 i386 running OSF/1 i[3456]86-*osf1mk*
5422 HP/Apollo 68k Family m68*-apollo*-sysv*,
5424 m68*-hp-bsd*, m68*-hp-hpux*
5425 I960 with MON960 i960-*-coff
5427 * OBSOLETE languages
5429 CHILL, a Pascal like language used by telecommunications companies.
5431 * REMOVED configurations and files
5433 AMD 29k family via UDI a29k-amd-udi, udi29k
5434 A29K VxWorks a29k-*-vxworks
5435 AMD 29000 embedded, using EBMON a29k-none-none
5436 AMD 29000 embedded with COFF a29k-none-coff
5437 AMD 29000 embedded with a.out a29k-none-aout
5439 testsuite/gdb.hp/gdb.threads-hp/ directory
5441 * New command "set max-user-call-depth <nnn>"
5443 This command allows the user to limit the call depth of user-defined
5444 commands. The default is 1024.
5446 * Changes in FreeBSD/i386 native debugging.
5448 Support for the "generate-core-file" has been added.
5450 * New commands "dump", "append", and "restore".
5452 These commands allow data to be copied from target memory
5453 to a bfd-format or binary file (dump and append), and back
5454 from a file into memory (restore).
5456 * Improved "next/step" support on multi-processor Alpha Tru64.
5458 The previous single-step mechanism could cause unpredictable problems,
5459 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5460 of a software single-step mechanism prevents this.
5462 *** Changes in GDB 5.2.1:
5470 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5471 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5472 Fix, by Joel Brobecker imported from mainline.
5474 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5475 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5476 Fix, by Fred Fish, imported from mainline.
5478 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5479 Surprisingly enough, it works now.
5480 By Michal Ludvig, imported from mainline.
5482 i386 hardware watchpoint support:
5483 avoid misses on second run for some targets.
5484 By Pierre Muller, imported from mainline.
5486 *** Changes in GDB 5.2:
5488 * New command "set trust-readonly-sections on[off]".
5490 This command is a hint that tells gdb that read-only sections
5491 really are read-only (ie. that their contents will not change).
5492 In this mode, gdb will go to the object file rather than the
5493 target to read memory from read-only sections (such as ".text").
5494 This can be a significant performance improvement on some
5495 (notably embedded) targets.
5497 * New command "generate-core-file" (or "gcore").
5499 This new gdb command allows the user to drop a core file of the child
5500 process state at any time. So far it's been implemented only for
5501 GNU/Linux and Solaris, but should be relatively easily ported to other
5502 hosts. Argument is core file name (defaults to core.<pid>).
5504 * New command line option
5506 GDB now accepts --pid or -p followed by a process id.
5508 * Change in command line behavior -- corefiles vs. process ids.
5510 There is a subtle behavior in the way in which GDB handles
5511 command line arguments. The first non-flag argument is always
5512 a program to debug, but the second non-flag argument may either
5513 be a corefile or a process id. Previously, GDB would attempt to
5514 open the second argument as a corefile, and if that failed, would
5515 issue a superfluous error message and then attempt to attach it as
5516 a process. Now, if the second argument begins with a non-digit,
5517 it will be treated as a corefile. If it begins with a digit,
5518 GDB will attempt to attach it as a process, and if no such process
5519 is found, will then attempt to open it as a corefile.
5521 * Changes in ARM configurations.
5523 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5524 configuration is fully multi-arch.
5526 * New native configurations
5528 ARM NetBSD arm*-*-netbsd*
5529 x86 OpenBSD i[3456]86-*-openbsd*
5530 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5531 Sparc64 running FreeBSD sparc64-*-freebsd*
5535 Sanyo XStormy16 xstormy16-elf
5537 * OBSOLETE configurations and files
5539 Configurations that have been declared obsolete in this release have
5540 been commented out. Unless there is activity to revive these
5541 configurations, the next release of GDB will have their sources
5542 permanently REMOVED.
5544 AMD 29k family via UDI a29k-amd-udi, udi29k
5545 A29K VxWorks a29k-*-vxworks
5546 AMD 29000 embedded, using EBMON a29k-none-none
5547 AMD 29000 embedded with COFF a29k-none-coff
5548 AMD 29000 embedded with a.out a29k-none-aout
5550 testsuite/gdb.hp/gdb.threads-hp/ directory
5552 * REMOVED configurations and files
5554 TI TMS320C80 tic80-*-*
5556 PowerPC Solaris powerpcle-*-solaris*
5557 PowerPC Windows NT powerpcle-*-cygwin32
5558 PowerPC Netware powerpc-*-netware*
5559 Harris/CXUX m88k m88*-harris-cxux*
5560 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5561 ns32k-utek-sysv* ns32k-utek-*
5562 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5563 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5564 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5565 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5566 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5568 * Changes to command line processing
5570 The new `--args' feature can be used to specify command-line arguments
5571 for the inferior from gdb's command line.
5573 * Changes to key bindings
5575 There is a new `operate-and-get-next' function bound to `C-o'.
5577 *** Changes in GDB 5.1.1
5579 Fix compile problem on DJGPP.
5581 Fix a problem with floating-point registers on the i386 being
5584 Fix to stop GDB crashing on .debug_str debug info.
5586 Numerous documentation fixes.
5588 Numerous testsuite fixes.
5590 *** Changes in GDB 5.1:
5592 * New native configurations
5594 Alpha FreeBSD alpha*-*-freebsd*
5595 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5596 MIPS GNU/Linux mips*-*-linux*
5597 MIPS SGI Irix 6.x mips*-sgi-irix6*
5598 ia64 AIX ia64-*-aix*
5599 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5603 Motorola 68HC11 and 68HC12 m68hc11-elf
5605 UltraSparc running GNU/Linux sparc64-*-linux*
5607 * OBSOLETE configurations and files
5609 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5610 Harris/CXUX m88k m88*-harris-cxux*
5611 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5612 ns32k-utek-sysv* ns32k-utek-*
5613 TI TMS320C80 tic80-*-*
5615 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5616 PowerPC Solaris powerpcle-*-solaris*
5617 PowerPC Windows NT powerpcle-*-cygwin32
5618 PowerPC Netware powerpc-*-netware*
5619 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5620 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5621 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5622 Apple Macintosh (MPW) host N/A
5624 stuff.c (Program to stuff files into a specially prepared space in kdb)
5625 kdb-start.c (Main loop for the standalone kernel debugger)
5627 Configurations that have been declared obsolete in this release have
5628 been commented out. Unless there is activity to revive these
5629 configurations, the next release of GDB will have their sources
5630 permanently REMOVED.
5632 * REMOVED configurations and files
5634 Altos 3068 m68*-altos-*
5635 Convex c1-*-*, c2-*-*
5637 ARM RISCix arm-*-* (as host)
5641 * GDB has been converted to ISO C.
5643 GDB's source code has been converted to ISO C. In particular, the
5644 sources are fully protoized, and rely on standard headers being
5649 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5651 * The MI enabled by default.
5653 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5654 revised and enabled by default. Packages which use GDB as a debugging
5655 engine behind a UI or another front end are encouraged to switch to
5656 using the GDB/MI interface, instead of the old annotations interface
5657 which is now deprecated.
5659 * Support for debugging Pascal programs.
5661 GDB now includes support for debugging Pascal programs. The following
5662 main features are supported:
5664 - Pascal-specific data types such as sets;
5666 - automatic recognition of Pascal sources based on file-name
5669 - Pascal-style display of data types, variables, and functions;
5671 - a Pascal expression parser.
5673 However, some important features are not yet supported.
5675 - Pascal string operations are not supported at all;
5677 - there are some problems with boolean types;
5679 - Pascal type hexadecimal constants are not supported
5680 because they conflict with the internal variables format;
5682 - support for Pascal objects and classes is not full yet;
5684 - unlike Pascal, GDB is case-sensitive for symbol names.
5686 * Changes in completion.
5688 Commands such as `shell', `run' and `set args', which pass arguments
5689 to inferior programs, now complete on file names, similar to what
5690 users expect at the shell prompt.
5692 Commands which accept locations, such as `disassemble', `print',
5693 `breakpoint', `until', etc. now complete on filenames as well as
5694 program symbols. Thus, if you type "break foob TAB", and the source
5695 files linked into the programs include `foobar.c', that file name will
5696 be one of the candidates for completion. However, file names are not
5697 considered for completion after you typed a colon that delimits a file
5698 name from a name of a function in that file, as in "break foo.c:bar".
5700 `set demangle-style' completes on available demangling styles.
5702 * New platform-independent commands:
5704 It is now possible to define a post-hook for a command as well as a
5705 hook that runs before the command. For more details, see the
5706 documentation of `hookpost' in the GDB manual.
5708 * Changes in GNU/Linux native debugging.
5710 Support for debugging multi-threaded programs has been completely
5711 revised for all platforms except m68k and sparc. You can now debug as
5712 many threads as your system allows you to have.
5714 Attach/detach is supported for multi-threaded programs.
5716 Support for SSE registers was added for x86. This doesn't work for
5717 multi-threaded programs though.
5719 * Changes in MIPS configurations.
5721 Multi-arch support is enabled for all MIPS configurations.
5723 GDB can now be built as native debugger on SGI Irix 6.x systems for
5724 debugging n32 executables. (Debugging 64-bit executables is not yet
5727 * Unified support for hardware watchpoints in all x86 configurations.
5729 Most (if not all) native x86 configurations support hardware-assisted
5730 breakpoints and watchpoints in a unified manner. This support
5731 implements debug register sharing between watchpoints, which allows to
5732 put a virtually infinite number of watchpoints on the same address,
5733 and also supports watching regions up to 16 bytes with several debug
5736 The new maintenance command `maintenance show-debug-regs' toggles
5737 debugging print-outs in functions that insert, remove, and test
5738 watchpoints and hardware breakpoints.
5740 * Changes in the DJGPP native configuration.
5742 New command ``info dos sysinfo'' displays assorted information about
5743 the CPU, OS, memory, and DPMI server.
5745 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5746 display information about segment descriptors stored in GDT, LDT, and
5749 New commands ``info dos pde'' and ``info dos pte'' display entries
5750 from Page Directory and Page Tables (for now works with CWSDPMI only).
5751 New command ``info dos address-pte'' displays the Page Table entry for
5752 a given linear address.
5754 GDB can now pass command lines longer than 126 characters to the
5755 program being debugged (requires an update to the libdbg.a library
5756 which is part of the DJGPP development kit).
5758 DWARF2 debug info is now supported.
5760 It is now possible to `step' and `next' through calls to `longjmp'.
5762 * Changes in documentation.
5764 All GDB documentation was converted to GFDL, the GNU Free
5765 Documentation License.
5767 Tracepoints-related commands are now fully documented in the GDB
5770 TUI, the Text-mode User Interface, is now documented in the manual.
5772 Tracepoints-related commands are now fully documented in the GDB
5775 The "GDB Internals" manual now has an index. It also includes
5776 documentation of `ui_out' functions, GDB coding standards, x86
5777 hardware watchpoints, and memory region attributes.
5779 * GDB's version number moved to ``version.in''
5781 The Makefile variable VERSION has been replaced by the file
5782 ``version.in''. People creating GDB distributions should update the
5783 contents of this file.
5787 GUD support is now a standard part of the EMACS distribution.
5789 *** Changes in GDB 5.0:
5791 * Improved support for debugging FP programs on x86 targets
5793 Unified and much-improved support for debugging floating-point
5794 programs on all x86 targets. In particular, ``info float'' now
5795 displays the FP registers in the same format on all x86 targets, with
5796 greater level of detail.
5798 * Improvements and bugfixes in hardware-assisted watchpoints
5800 It is now possible to watch array elements, struct members, and
5801 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5802 on x86 targets no longer erroneously trigger when the address is
5805 * Improvements in the native DJGPP version of GDB
5807 The distribution now includes all the scripts and auxiliary files
5808 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5809 machines ``out of the box''.
5811 The DJGPP version can now debug programs that use signals. It is
5812 possible to catch signals that happened in the debuggee, deliver
5813 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5814 would kill the program being debugged.) Programs that hook hardware
5815 interrupts (keyboard, timer, etc.) can also be debugged.
5817 It is now possible to debug DJGPP programs that redirect their
5818 standard handles or switch them to raw (as opposed to cooked) mode, or
5819 even close them. The command ``run < foo > bar'' works as expected,
5820 and ``info terminal'' reports useful information about the debuggee's
5821 terminal, including raw/cooked mode, redirection, etc.
5823 The DJGPP version now uses termios functions for console I/O, which
5824 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5827 DOS-style file names with drive letters are now fully supported by
5830 It is now possible to debug DJGPP programs that switch their working
5831 directory. It is also possible to rerun the debuggee any number of
5832 times without restarting GDB; thus, you can use the same setup,
5833 breakpoints, etc. for many debugging sessions.
5835 * New native configurations
5837 ARM GNU/Linux arm*-*-linux*
5838 PowerPC GNU/Linux powerpc-*-linux*
5842 Motorola MCore mcore-*-*
5843 x86 VxWorks i[3456]86-*-vxworks*
5844 PowerPC VxWorks powerpc-*-vxworks*
5845 TI TMS320C80 tic80-*-*
5847 * OBSOLETE configurations
5849 Altos 3068 m68*-altos-*
5850 Convex c1-*-*, c2-*-*
5852 ARM RISCix arm-*-* (as host)
5855 Configurations that have been declared obsolete will be commented out,
5856 but the code will be left in place. If there is no activity to revive
5857 these configurations before the next release of GDB, the sources will
5858 be permanently REMOVED.
5860 * Gould support removed
5862 Support for the Gould PowerNode and NP1 has been removed.
5864 * New features for SVR4
5866 On SVR4 native platforms (such as Solaris), if you attach to a process
5867 without first loading a symbol file, GDB will now attempt to locate and
5868 load symbols from the running process's executable file.
5870 * Many C++ enhancements
5872 C++ support has been greatly improved. Overload resolution now works properly
5873 in almost all cases. RTTI support is on the way.
5875 * Remote targets can connect to a sub-program
5877 A popen(3) style serial-device has been added. This device starts a
5878 sub-process (such as a stand-alone simulator) and then communicates
5879 with that. The sub-program to run is specified using the syntax
5880 ``|<program> <args>'' vis:
5882 (gdb) set remotedebug 1
5883 (gdb) target extended-remote |mn10300-elf-sim program-args
5885 * MIPS 64 remote protocol
5887 A long standing bug in the mips64 remote protocol where by GDB
5888 expected certain 32 bit registers (ex SR) to be transfered as 32
5889 instead of 64 bits has been fixed.
5891 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5892 added to provide backward compatibility with older versions of GDB.
5894 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5896 The command ``set remotebinarydownload'' command has been replaced by
5897 ``set remote X-packet''. Other commands in ``set remote'' family
5898 include ``set remote P-packet''.
5900 * Breakpoint commands accept ranges.
5902 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5903 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5904 ``tracepoint passcount'' also accepts a range of tracepoints.
5906 * ``apropos'' command added.
5908 The ``apropos'' command searches through command names and
5909 documentation strings, printing out matches, making it much easier to
5910 try to find a command that does what you are looking for.
5914 A new machine oriented interface (MI) has been added to GDB. This
5915 interface is designed for debug environments running GDB as a separate
5916 process. This is part of the long term libGDB project. See the
5917 "GDB/MI" chapter of the GDB manual for further information. It can be
5918 enabled by configuring with:
5920 .../configure --enable-gdbmi
5922 *** Changes in GDB-4.18:
5924 * New native configurations
5926 HP-UX 10.20 hppa*-*-hpux10.20
5927 HP-UX 11.x hppa*-*-hpux11.0*
5928 M68K GNU/Linux m68*-*-linux*
5932 Fujitsu FR30 fr30-*-elf*
5933 Intel StrongARM strongarm-*-*
5934 Mitsubishi D30V d30v-*-*
5936 * OBSOLETE configurations
5938 Gould PowerNode, NP1 np1-*-*, pn-*-*
5940 Configurations that have been declared obsolete will be commented out,
5941 but the code will be left in place. If there is no activity to revive
5942 these configurations before the next release of GDB, the sources will
5943 be permanently REMOVED.
5947 As a compatibility experiment, GDB's source files buildsym.h and
5948 buildsym.c have been converted to pure standard C, no longer
5949 containing any K&R compatibility code. We believe that all systems in
5950 use today either come with a standard C compiler, or have a GCC port
5951 available. If this is not true, please report the affected
5952 configuration to bug-gdb@gnu.org immediately. See the README file for
5953 information about getting a standard C compiler if you don't have one
5958 GDB now uses readline 2.2.
5960 * set extension-language
5962 You can now control the mapping between filename extensions and source
5963 languages by using the `set extension-language' command. For instance,
5964 you can ask GDB to treat .c files as C++ by saying
5965 set extension-language .c c++
5966 The command `info extensions' lists all of the recognized extensions
5967 and their associated languages.
5969 * Setting processor type for PowerPC and RS/6000
5971 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5972 you can use the `set processor' command to specify what variant of the
5973 PowerPC family you are debugging. The command
5977 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5978 following PowerPC and RS6000 variants:
5980 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5981 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5983 403GC IBM PowerPC 403GC
5984 505 Motorola PowerPC 505
5985 860 Motorola PowerPC 860 or 850
5986 601 Motorola PowerPC 601
5987 602 Motorola PowerPC 602
5988 603 Motorola/IBM PowerPC 603 or 603e
5989 604 Motorola PowerPC 604 or 604e
5990 750 Motorola/IBM PowerPC 750 or 750
5992 At the moment, this command just tells GDB what to name the
5993 special-purpose processor registers. Since almost all the affected
5994 registers are inaccessible to user-level programs, this command is
5995 only useful for remote debugging in its present form.
5999 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6000 more extensive support for HP-UX. Added features include shared
6001 library support, kernel threads and hardware watchpoints for 11.00,
6002 support for HP's ANSI C and C++ compilers, and a compatibility mode
6003 for xdb and dbx commands.
6007 HP's donation includes the new concept of catchpoints, which is a
6008 generalization of the old catch command. On HP-UX, it is now possible
6009 to catch exec, fork, and vfork, as well as library loading.
6011 This means that the existing catch command has changed; its first
6012 argument now specifies the type of catch to be set up. See the
6013 output of "help catch" for a list of catchpoint types.
6015 * Debugging across forks
6017 On HP-UX, you can choose which process to debug when a fork() happens
6022 HP has donated a curses-based terminal user interface (TUI). To get
6023 it, build with --enable-tui. Although this can be enabled for any
6024 configuration, at present it only works for native HP debugging.
6026 * GDB remote protocol additions
6028 A new protocol packet 'X' that writes binary data is now available.
6029 Default behavior is to try 'X', then drop back to 'M' if the stub
6030 fails to respond. The settable variable `remotebinarydownload'
6031 allows explicit control over the use of 'X'.
6033 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6034 full 64-bit address. The command
6036 set remoteaddresssize 32
6038 can be used to revert to the old behaviour. For existing remote stubs
6039 the change should not be noticed, as the additional address information
6042 In order to assist in debugging stubs, you may use the maintenance
6043 command `packet' to send any text string to the stub. For instance,
6045 maint packet heythere
6047 sends the packet "$heythere#<checksum>". Note that it is very easy to
6048 disrupt a debugging session by sending the wrong packet at the wrong
6051 The compare-sections command allows you to compare section data on the
6052 target to what is in the executable file without uploading or
6053 downloading, by comparing CRC checksums.
6055 * Tracing can collect general expressions
6057 You may now collect general expressions at tracepoints. This requires
6058 further additions to the target-side stub; see tracepoint.c and
6059 doc/agentexpr.texi for further details.
6061 * mask-address variable for Mips
6063 For Mips targets, you may control the zeroing of the upper 32 bits of
6064 a 64-bit address by entering `set mask-address on'. This is mainly
6065 of interest to users of embedded R4xxx and R5xxx processors.
6067 * Higher serial baud rates
6069 GDB's serial code now allows you to specify baud rates 57600, 115200,
6070 230400, and 460800 baud. (Note that your host system may not be able
6071 to achieve all of these rates.)
6075 The i960 configuration now includes an initial implementation of a
6076 builtin simulator, contributed by Jim Wilson.
6079 *** Changes in GDB-4.17:
6081 * New native configurations
6083 Alpha GNU/Linux alpha*-*-linux*
6084 Unixware 2.x i[3456]86-unixware2*
6085 Irix 6.x mips*-sgi-irix6*
6086 PowerPC GNU/Linux powerpc-*-linux*
6087 PowerPC Solaris powerpcle-*-solaris*
6088 Sparc GNU/Linux sparc-*-linux*
6089 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6093 Argonaut Risc Chip (ARC) arc-*-*
6094 Hitachi H8/300S h8300*-*-*
6095 Matsushita MN10200 w/simulator mn10200-*-*
6096 Matsushita MN10300 w/simulator mn10300-*-*
6097 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6098 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6099 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6100 Mitsubishi D10V w/simulator d10v-*-*
6101 Mitsubishi M32R/D w/simulator m32r-*-elf*
6102 Tsqware Sparclet sparclet-*-*
6103 NEC V850 w/simulator v850-*-*
6105 * New debugging protocols
6107 ARM with RDI protocol arm*-*-*
6108 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6109 DDB and LSI variants of PMON protocol mips*-*-*
6110 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6111 PowerPC with SDS protocol powerpc{,le}-*-eabi
6112 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6116 All configurations can now understand and use the DWARF 2 debugging
6117 format. The choice is automatic, if the symbol file contains DWARF 2
6122 GDB now includes basic Java language support. This support is
6123 only useful with Java compilers that produce native machine code.
6125 * solib-absolute-prefix and solib-search-path
6127 For SunOS and SVR4 shared libraries, you may now set the prefix for
6128 loading absolute shared library symbol files, and the search path for
6129 locating non-absolute shared library symbol files.
6131 * Live range splitting
6133 GDB can now effectively debug code for which GCC has performed live
6134 range splitting as part of its optimization. See gdb/doc/LRS for
6135 more details on the expected format of the stabs information.
6139 GDB's support for the GNU Hurd, including thread debugging, has been
6140 updated to work with current versions of the Hurd.
6144 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6145 instruction set. ARM GDB automatically detects when Thumb
6146 instructions are in use, and adjusts disassembly and backtracing
6151 GDB's MIPS target configurations now handle the MIP16 16-bit
6156 GDB now includes support for overlays; if an executable has been
6157 linked such that multiple sections are based at the same address, GDB
6158 will decide which section to use for symbolic info. You can choose to
6159 control the decision manually, using overlay commands, or implement
6160 additional target-side support and use "overlay load-target" to bring
6161 in the overlay mapping. Do "help overlay" for more detail.
6165 The command "info symbol <address>" displays information about
6166 the symbol at the specified address.
6170 The standard remote protocol now includes an extension that allows
6171 asynchronous collection and display of trace data. This requires
6172 extensive support in the target-side debugging stub. Tracing mode
6173 includes a new interaction mode in GDB and new commands: see the
6174 file tracepoint.c for more details.
6178 Configurations for embedded MIPS now include a simulator contributed
6179 by Cygnus Solutions. The simulator supports the instruction sets
6180 of most MIPS variants.
6184 Sparc configurations may now include the ERC32 simulator contributed
6185 by the European Space Agency. The simulator is not built into
6186 Sparc targets by default; configure with --enable-sim to include it.
6190 For target configurations that may include multiple variants of a
6191 basic architecture (such as MIPS and SH), you may now set the
6192 architecture explicitly. "set arch" sets, "info arch" lists
6193 the possible architectures.
6195 *** Changes in GDB-4.16:
6197 * New native configurations
6199 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6200 M68K NetBSD m68k-*-netbsd*
6201 PowerPC AIX 4.x powerpc-*-aix*
6202 PowerPC MacOS powerpc-*-macos*
6203 PowerPC Windows NT powerpcle-*-cygwin32
6204 RS/6000 AIX 4.x rs6000-*-aix4*
6208 ARM with RDP protocol arm-*-*
6209 I960 with MON960 i960-*-coff
6210 MIPS VxWorks mips*-*-vxworks*
6211 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6212 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6214 Matra Sparclet sparclet-*-*
6218 The powerpc-eabi configuration now includes the PSIM simulator,
6219 contributed by Andrew Cagney, with assistance from Mike Meissner.
6220 PSIM is a very elaborate model of the PowerPC, including not only
6221 basic instruction set execution, but also details of execution unit
6222 performance and I/O hardware. See sim/ppc/README for more details.
6226 GDB now works with Solaris 2.5.
6228 * Windows 95/NT native
6230 GDB will now work as a native debugger on Windows 95 and Windows NT.
6231 To build it from source, you must use the "gnu-win32" environment,
6232 which uses a DLL to emulate enough of Unix to run the GNU tools.
6233 Further information, binaries, and sources are available at
6234 ftp.cygnus.com, under pub/gnu-win32.
6236 * dont-repeat command
6238 If a user-defined command includes the command `dont-repeat', then the
6239 command will not be repeated if the user just types return. This is
6240 useful if the command is time-consuming to run, so that accidental
6241 extra keystrokes don't run the same command many times.
6243 * Send break instead of ^C
6245 The standard remote protocol now includes an option to send a break
6246 rather than a ^C to the target in order to interrupt it. By default,
6247 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6249 * Remote protocol timeout
6251 The standard remote protocol includes a new variable `remotetimeout'
6252 that allows you to set the number of seconds before GDB gives up trying
6253 to read from the target. The default value is 2.
6255 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6257 By default GDB will automatically keep track of objects as they are
6258 loaded and unloaded by the dynamic linker. By using the command `set
6259 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6260 when shared library events occur, thus allowing you to set breakpoints
6261 in shared libraries which are explicitly loaded by the inferior.
6263 Note this feature does not work on hpux8. On hpux9 you must link
6264 /usr/lib/end.o into your program. This feature should work
6265 automatically on hpux10.
6267 * Irix 5.x hardware watchpoint support
6269 Irix 5 configurations now support the use of hardware watchpoints.
6271 * Mips protocol "SYN garbage limit"
6273 When debugging a Mips target using the `target mips' protocol, you
6274 may set the number of characters that GDB will ignore by setting
6275 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6276 every character. The default value is 1050.
6278 * Recording and replaying remote debug sessions
6280 If you set `remotelogfile' to the name of a file, gdb will write to it
6281 a recording of a remote debug session. This recording may then be
6282 replayed back to gdb using "gdbreplay". See gdbserver/README for
6283 details. This is useful when you have a problem with GDB while doing
6284 remote debugging; you can make a recording of the session and send it
6285 to someone else, who can then recreate the problem.
6287 * Speedups for remote debugging
6289 GDB includes speedups for downloading and stepping MIPS systems using
6290 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6291 and more efficient S-record downloading.
6293 * Memory use reductions and statistics collection
6295 GDB now uses less memory and reports statistics about memory usage.
6296 Try the `maint print statistics' command, for example.
6298 *** Changes in GDB-4.15:
6300 * Psymtabs for XCOFF
6302 The symbol reader for AIX GDB now uses partial symbol tables. This
6303 can greatly improve startup time, especially for large executables.
6305 * Remote targets use caching
6307 Remote targets now use a data cache to speed up communication with the
6308 remote side. The data cache could lead to incorrect results because
6309 it doesn't know about volatile variables, thus making it impossible to
6310 debug targets which use memory mapped I/O devices. `set remotecache
6311 off' turns the the data cache off.
6313 * Remote targets may have threads
6315 The standard remote protocol now includes support for multiple threads
6316 in the target system, using new protocol commands 'H' and 'T'. See
6317 gdb/remote.c for details.
6321 If GDB is configured with `--enable-netrom', then it will include
6322 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6323 acts as though it is a bank of ROM on the target board, but you can
6324 write into it over the network. GDB's support consists only of
6325 support for fast loading into the emulated ROM; to debug, you must use
6326 another protocol, such as standard remote protocol. The usual
6327 sequence is something like
6329 target nrom <netrom-hostname>
6331 target remote <netrom-hostname>:1235
6335 GDB now includes support for the Apple Macintosh, as a host only. It
6336 may be run as either an MPW tool or as a standalone application, and
6337 it can debug through the serial port. All the usual GDB commands are
6338 available, but to the target command, you must supply "serial" as the
6339 device type instead of "/dev/ttyXX". See mpw-README in the main
6340 directory for more information on how to build. The MPW configuration
6341 scripts */mpw-config.in support only a few targets, and only the
6342 mips-idt-ecoff target has been tested.
6346 GDB configuration now uses autoconf. This is not user-visible,
6347 but does simplify configuration and building.
6351 GDB now supports hpux10.
6353 *** Changes in GDB-4.14:
6355 * New native configurations
6357 x86 FreeBSD i[345]86-*-freebsd
6358 x86 NetBSD i[345]86-*-netbsd
6359 NS32k NetBSD ns32k-*-netbsd
6360 Sparc NetBSD sparc-*-netbsd
6364 A29K VxWorks a29k-*-vxworks
6365 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6366 CPU32 EST-300 emulator m68*-*-est*
6367 PowerPC ELF powerpc-*-elf
6370 * Alpha OSF/1 support for procfs
6372 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6373 possible to attach to running processes. As the mounting of the /proc
6374 filesystem is optional on the Alpha, GDB automatically determines
6375 the availability of /proc during startup. This can lead to problems
6376 if /proc is unmounted after GDB has been started.
6378 * Arguments to user-defined commands
6380 User commands may accept up to 10 arguments separated by whitespace.
6381 Arguments are accessed within the user command via $arg0..$arg9. A
6384 print $arg0 + $arg1 + $arg2
6386 To execute the command use:
6389 Defines the command "adder" which prints the sum of its three arguments.
6390 Note the arguments are text substitutions, so they may reference variables,
6391 use complex expressions, or even perform inferior function calls.
6393 * New `if' and `while' commands
6395 This makes it possible to write more sophisticated user-defined
6396 commands. Both commands take a single argument, which is the
6397 expression to evaluate, and must be followed by the commands to
6398 execute, one per line, if the expression is nonzero, the list being
6399 terminated by the word `end'. The `if' command list may include an
6400 `else' word, which causes the following commands to be executed only
6401 if the expression is zero.
6403 * Fortran source language mode
6405 GDB now includes partial support for Fortran 77. It will recognize
6406 Fortran programs and can evaluate a subset of Fortran expressions, but
6407 variables and functions may not be handled correctly. GDB will work
6408 with G77, but does not yet know much about symbols emitted by other
6411 * Better HPUX support
6413 Most debugging facilities now work on dynamic executables for HPPAs
6414 running hpux9 or later. You can attach to running dynamically linked
6415 processes, but by default the dynamic libraries will be read-only, so
6416 for instance you won't be able to put breakpoints in them. To change
6417 that behavior do the following before running the program:
6423 This will cause the libraries to be mapped private and read-write.
6424 To revert to the normal behavior, do this:
6430 You cannot set breakpoints or examine data in the library until after
6431 the library is loaded if the function/data symbols do not have
6434 GDB can now also read debug symbols produced by the HP C compiler on
6435 HPPAs (sorry, no C++, Fortran or 68k support).
6437 * Target byte order now dynamically selectable
6439 You can choose which byte order to use with a target system, via the
6440 commands "set endian big" and "set endian little", and you can see the
6441 current setting by using "show endian". You can also give the command
6442 "set endian auto", in which case GDB will use the byte order
6443 associated with the executable. Currently, only embedded MIPS
6444 configurations support dynamic selection of target byte order.
6446 * New DOS host serial code
6448 This version uses DPMI interrupts to handle buffered I/O, so you
6449 no longer need to run asynctsr when debugging boards connected to
6452 *** Changes in GDB-4.13:
6454 * New "complete" command
6456 This lists all the possible completions for the rest of the line, if it
6457 were to be given as a command itself. This is intended for use by emacs.
6459 * Trailing space optional in prompt
6461 "set prompt" no longer adds a space for you after the prompt you set. This
6462 allows you to set a prompt which ends in a space or one that does not.
6464 * Breakpoint hit counts
6466 "info break" now displays a count of the number of times the breakpoint
6467 has been hit. This is especially useful in conjunction with "ignore"; you
6468 can ignore a large number of breakpoint hits, look at the breakpoint info
6469 to see how many times the breakpoint was hit, then run again, ignoring one
6470 less than that number, and this will get you quickly to the last hit of
6473 * Ability to stop printing at NULL character
6475 "set print null-stop" will cause GDB to stop printing the characters of
6476 an array when the first NULL is encountered. This is useful when large
6477 arrays actually contain only short strings.
6479 * Shared library breakpoints
6481 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6482 breakpoints in shared libraries before the executable is run.
6484 * Hardware watchpoints
6486 There is a new hardware breakpoint for the watch command for sparclite
6487 targets. See gdb/sparclite/hw_breakpoint.note.
6489 Hardware watchpoints are also now supported under GNU/Linux.
6493 Annotations have been added. These are for use with graphical interfaces,
6494 and are still experimental. Currently only gdba.el uses these.
6496 * Improved Irix 5 support
6498 GDB now works properly with Irix 5.2.
6500 * Improved HPPA support
6502 GDB now works properly with the latest GCC and GAS.
6504 * New native configurations
6506 Sequent PTX4 i[34]86-sequent-ptx4
6507 HPPA running OSF/1 hppa*-*-osf*
6508 Atari TT running SVR4 m68*-*-sysv4*
6509 RS/6000 LynxOS rs6000-*-lynxos*
6513 OS/9000 i[34]86-*-os9k
6514 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6517 * Hitachi SH7000 and E7000-PC ICE support
6519 There is now support for communicating with the Hitachi E7000-PC ICE.
6520 This is available automatically when GDB is configured for the SH.
6524 As usual, a variety of small fixes and improvements, both generic
6525 and configuration-specific. See the ChangeLog for more detail.
6527 *** Changes in GDB-4.12:
6529 * Irix 5 is now supported
6533 GDB-4.12 on the HPPA has a number of changes which make it unable
6534 to debug the output from the currently released versions of GCC and
6535 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6536 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6537 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6540 *** Changes in GDB-4.11:
6542 * User visible changes:
6546 The "set remotedebug" option is now consistent between the mips remote
6547 target, remote targets using the gdb-specific protocol, UDI (AMD's
6548 debug protocol for the 29k) and the 88k bug monitor. It is now an
6549 integer specifying a debug level (normally 0 or 1, but 2 means more
6550 debugging info for the mips target).
6552 * DEC Alpha native support
6554 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6555 debug info, but GDB works fairly well with the DEC compiler and should
6556 work with a future GCC release. See the README file for a few
6557 Alpha-specific notes.
6559 * Preliminary thread implementation
6561 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6563 * LynxOS native and target support for 386
6565 This release has been hosted on LynxOS 2.2, and also can be configured
6566 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6569 * Improvements in C++ mangling/demangling.
6571 This release has much better g++ debugging, specifically in name
6572 mangling/demangling, virtual function calls, print virtual table,
6573 call methods, ...etc.
6575 *** Changes in GDB-4.10:
6577 * User visible changes:
6579 Remote debugging using the GDB-specific (`target remote') protocol now
6580 supports the `load' command. This is only useful if you have some
6581 other way of getting the stub to the target system, and you can put it
6582 somewhere in memory where it won't get clobbered by the download.
6584 Filename completion now works.
6586 When run under emacs mode, the "info line" command now causes the
6587 arrow to point to the line specified. Also, "info line" prints
6588 addresses in symbolic form (as well as hex).
6590 All vxworks based targets now support a user settable option, called
6591 vxworks-timeout. This option represents the number of seconds gdb
6592 should wait for responses to rpc's. You might want to use this if
6593 your vxworks target is, perhaps, a slow software simulator or happens
6594 to be on the far side of a thin network line.
6598 This release contains support for using a DEC alpha as a GDB host for
6599 cross debugging. Native alpha debugging is not supported yet.
6602 *** Changes in GDB-4.9:
6606 This is the first GDB release which is accompanied by a matching testsuite.
6607 The testsuite requires installation of dejagnu, which should be available
6608 via ftp from most sites that carry GNU software.
6612 'Cfront' style demangling has had its name changed to 'ARM' style, to
6613 emphasize that it was written from the specifications in the C++ Annotated
6614 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6615 disclaimers, it still generated too much confusion with users attempting to
6616 use gdb with AT&T cfront.
6620 GDB now uses a standard remote interface to a simulator library.
6621 So far, the library contains simulators for the Zilog Z8001/2, the
6622 Hitachi H8/300, H8/500 and Super-H.
6624 * New targets supported
6626 H8/300 simulator h8300-hitachi-hms or h8300hms
6627 H8/500 simulator h8500-hitachi-hms or h8500hms
6628 SH simulator sh-hitachi-hms or sh
6629 Z8000 simulator z8k-zilog-none or z8ksim
6630 IDT MIPS board over serial line mips-idt-ecoff
6632 Cross-debugging to GO32 targets is supported. It requires a custom
6633 version of the i386-stub.c module which is integrated with the
6634 GO32 memory extender.
6636 * New remote protocols
6638 MIPS remote debugging protocol.
6640 * New source languages supported
6642 This version includes preliminary support for Chill, a Pascal like language
6643 used by telecommunications companies. Chill support is also being integrated
6644 into the GNU compiler, but we don't know when it will be publically available.
6647 *** Changes in GDB-4.8:
6649 * HP Precision Architecture supported
6651 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6652 version of this support was available as a set of patches from the
6653 University of Utah. GDB does not support debugging of programs
6654 compiled with the HP compiler, because HP will not document their file
6655 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6656 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6658 Many problems in the preliminary version have been fixed.
6660 * Faster and better demangling
6662 We have improved template demangling and fixed numerous bugs in the GNU style
6663 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6664 character types (wchar_t) are now supported. Demangling of each symbol is now
6665 only done once, and is cached when the symbol table for a file is read in.
6666 This results in a small increase in memory usage for C programs, a moderate
6667 increase in memory usage for C++ programs, and a fantastic speedup in
6670 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6671 from the specifications in the Annotated Reference Manual, which AT&T's
6672 compiler does not actually implement.
6674 * G++ multiple inheritance compiler problem
6676 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6677 inheritance lattices was reworked to properly discover ambiguities. We
6678 recently found an example which causes this new algorithm to fail in a
6679 very subtle way, producing bad debug information for those classes.
6680 The file 'gcc.patch' (in this directory) can be applied to gcc to
6681 circumvent the problem. A future GCC release will contain a complete
6684 The previous G++ debug info problem (mentioned below for the gdb-4.7
6685 release) is fixed in gcc version 2.3.2.
6687 * Improved configure script
6689 The `configure' script will now attempt to guess your system type if
6690 you don't supply a host system type. The old scheme of supplying a
6691 host system triplet is preferable over using this. All the magic is
6692 done in the new `config.guess' script. Examine it for details.
6694 We have also brought our configure script much more in line with the FSF's
6695 version. It now supports the --with-xxx options. In particular,
6696 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6697 The resulting GDB will not be able to read arbitrary object file formats --
6698 only the format ``expected'' to be used on the configured target system.
6699 We hope to make this the default in a future release.
6701 * Documentation improvements
6703 There's new internal documentation on how to modify GDB, and how to
6704 produce clean changes to the code. We implore people to read it
6705 before submitting changes.
6707 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6708 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6709 `info' files are also provided. To build `info' files from scratch,
6710 you will need the latest `makeinfo' release, which will be available in
6711 a future texinfo-X.Y release.
6713 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6714 We're not sure exactly which versions have this problem, but it has
6715 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6716 or better. If that isn't possible, there is a patch in
6717 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6718 around this problem.
6722 GDB now supports array constants that can be used in expressions typed in by
6723 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6724 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6727 The new directory `gdb/sparclite' contains a program that demonstrates
6728 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6730 * New native hosts supported
6732 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6733 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6735 * New targets supported
6737 AMD 29k family via UDI a29k-amd-udi or udi29k
6739 * New file formats supported
6741 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6742 HPUX core files, and SCO 3.2v2 core files.
6746 Attaching to processes now works again; thanks for the many bug reports.
6748 We have also stomped on a bunch of core dumps caused by
6749 printf_filtered("%s") problems.
6751 We eliminated a copyright problem on the rpc and ptrace header files
6752 for VxWorks, which was discovered at the last minute during the 4.7
6753 release. You should now be able to build a VxWorks GDB.
6755 You can now interrupt gdb while an attached process is running. This
6756 will cause the attached process to stop, and give control back to GDB.
6758 We fixed problems caused by using too many file descriptors
6759 for reading symbols from object files and libraries. This was
6760 especially a problem for programs that used many (~100) shared
6763 The `step' command now only enters a subroutine if there is line number
6764 information for the subroutine. Otherwise it acts like the `next'
6765 command. Previously, `step' would enter subroutines if there was
6766 any debugging information about the routine. This avoids problems
6767 when using `cc -g1' on MIPS machines.
6769 * Internal improvements
6771 GDB's internal interfaces have been improved to make it easier to support
6772 debugging of multiple languages in the future.
6774 GDB now uses a common structure for symbol information internally.
6775 Minimal symbols (derived from linkage symbols in object files), partial
6776 symbols (from a quick scan of debug information), and full symbols
6777 contain a common subset of information, making it easier to write
6778 shared code that handles any of them.
6780 * New command line options
6782 We now accept --silent as an alias for --quiet.
6786 The memory-mapped-malloc library is now licensed under the GNU Library
6787 General Public License.
6789 *** Changes in GDB-4.7:
6791 * Host/native/target split
6793 GDB has had some major internal surgery to untangle the support for
6794 hosts and remote targets. Now, when you configure GDB for a remote
6795 target, it will no longer load in all of the support for debugging
6796 local programs on the host. When fully completed and tested, this will
6797 ensure that arbitrary host/target combinations are possible.
6799 The primary conceptual shift is to separate the non-portable code in
6800 GDB into three categories. Host specific code is required any time GDB
6801 is compiled on that host, regardless of the target. Target specific
6802 code relates to the peculiarities of the target, but can be compiled on
6803 any host. Native specific code is everything else: it can only be
6804 built when the host and target are the same system. Child process
6805 handling and core file support are two common `native' examples.
6807 GDB's use of /proc for controlling Unix child processes is now cleaner.
6808 It has been split out into a single module under the `target_ops' vector,
6809 plus two native-dependent functions for each system that uses /proc.
6811 * New hosts supported
6813 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6814 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6815 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6817 * New targets supported
6819 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6820 68030 and CPU32 m68030-*-*, m68332-*-*
6822 * New native hosts supported
6824 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6825 (386bsd is not well tested yet)
6826 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6828 * New file formats supported
6830 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6831 supports reading of `a.out.adobe' object files, which are an a.out
6832 format extended with minimal information about multiple sections.
6836 `show copying' is the same as the old `info copying'.
6837 `show warranty' is the same as `info warrantee'.
6838 These were renamed for consistency. The old commands continue to work.
6840 `info handle' is a new alias for `info signals'.
6842 You can now define pre-command hooks, which attach arbitrary command
6843 scripts to any command. The commands in the hook will be executed
6844 prior to the user's command. You can also create a hook which will be
6845 executed whenever the program stops. See gdb.texinfo.
6849 We now deal with Cfront style name mangling, and can even extract type
6850 info from mangled symbols. GDB can automatically figure out which
6851 symbol mangling style your C++ compiler uses.
6853 Calling of methods and virtual functions has been improved as well.
6857 The crash that occured when debugging Sun Ansi-C compiled binaries is
6858 fixed. This was due to mishandling of the extra N_SO stabs output
6861 We also finally got Ultrix 4.2 running in house, and fixed core file
6862 support, with help from a dozen people on the net.
6864 John M. Farrell discovered that the reason that single-stepping was so
6865 slow on all of the Mips based platforms (primarily SGI and DEC) was
6866 that we were trying to demangle and lookup a symbol used for internal
6867 purposes on every instruction that was being stepped through. Changing
6868 the name of that symbol so that it couldn't be mistaken for a C++
6869 mangled symbol sped things up a great deal.
6871 Rich Pixley sped up symbol lookups in general by getting much smarter
6872 about when C++ symbol mangling is necessary. This should make symbol
6873 completion (TAB on the command line) much faster. It's not as fast as
6874 we'd like, but it's significantly faster than gdb-4.6.
6878 A new user controllable variable 'call_scratch_address' can
6879 specify the location of a scratch area to be used when GDB
6880 calls a function in the target. This is necessary because the
6881 usual method of putting the scratch area on the stack does not work
6882 in systems that have separate instruction and data spaces.
6884 We integrated changes to support the 29k UDI (Universal Debugger
6885 Interface), but discovered at the last minute that we didn't have all
6886 of the appropriate copyright paperwork. We are working with AMD to
6887 resolve this, and hope to have it available soon.
6891 We have sped up the remote serial line protocol, especially for targets
6892 with lots of registers. It now supports a new `expedited status' ('T')
6893 message which can be used in place of the existing 'S' status message.
6894 This allows the remote stub to send only the registers that GDB
6895 needs to make a quick decision about single-stepping or conditional
6896 breakpoints, eliminating the need to fetch the entire register set for
6897 each instruction being stepped through.
6899 The GDB remote serial protocol now implements a write-through cache for
6900 registers, only re-reading the registers if the target has run.
6902 There is also a new remote serial stub for SPARC processors. You can
6903 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6904 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6905 processor with a serial port.
6909 Configure.in files have become much easier to read and modify. A new
6910 `table driven' format makes it more obvious what configurations are
6911 supported, and what files each one uses.
6915 There is a new opcodes library which will eventually contain all of the
6916 disassembly routines and opcode tables. At present, it only contains
6917 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6918 disassembler (binutils/objdump) to share these routines.
6920 The libiberty library is now copylefted under the GNU Library General
6921 Public License. This allows more liberal use, and was done so libg++
6922 can use it. This makes no difference to GDB, since the Library License
6923 grants all the rights from the General Public License.
6927 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6928 reference to the stabs symbol info used by the debugger. It is (as far
6929 as we know) the only published document on this fascinating topic. We
6930 encourage you to read it, compare it to the stabs information on your
6931 system, and send improvements on the document in general (to
6932 bug-gdb@prep.ai.mit.edu).
6934 And, of course, many bugs have been fixed.
6937 *** Changes in GDB-4.6:
6939 * Better support for C++ function names
6941 GDB now accepts as input the "demangled form" of C++ overloaded function
6942 names and member function names, and can do command completion on such names
6943 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6944 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6945 Make use of command completion, it is your friend.
6947 GDB also now accepts a variety of C++ mangled symbol formats. They are
6948 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6949 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6950 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6951 for the list of formats.
6953 * G++ symbol mangling problem
6955 Recent versions of gcc have a bug in how they emit debugging information for
6956 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6957 directory) can be applied to gcc to fix the problem. Alternatively, if you
6958 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6959 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6960 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6963 * New 'maintenance' command
6965 All of the commands related to hacking GDB internals have been moved out of
6966 the main command set, and now live behind the 'maintenance' command. This
6967 can also be abbreviated as 'mt'. The following changes were made:
6969 dump-me -> maintenance dump-me
6970 info all-breakpoints -> maintenance info breakpoints
6971 printmsyms -> maintenance print msyms
6972 printobjfiles -> maintenance print objfiles
6973 printpsyms -> maintenance print psymbols
6974 printsyms -> maintenance print symbols
6976 The following commands are new:
6978 maintenance demangle Call internal GDB demangler routine to
6979 demangle a C++ link name and prints the result.
6980 maintenance print type Print a type chain for a given symbol
6982 * Change to .gdbinit file processing
6984 We now read the $HOME/.gdbinit file before processing the argv arguments
6985 (e.g. reading symbol files or core files). This allows global parameters to
6986 be set, which will apply during the symbol reading. The ./.gdbinit is still
6987 read after argv processing.
6989 * New hosts supported
6991 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6993 GNU/Linux support i386-unknown-linux or linux
6995 We are also including code to support the HP/PA running BSD and HPUX. This
6996 is almost guaranteed not to work, as we didn't have time to test or build it
6997 for this release. We are including it so that the more adventurous (or
6998 masochistic) of you can play with it. We also had major problems with the
6999 fact that the compiler that we got from HP doesn't support the -g option.
7002 * New targets supported
7004 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7006 * More smarts about finding #include files
7008 GDB now remembers the compilation directory for all include files, and for
7009 all files from which C is generated (like yacc and lex sources). This
7010 greatly improves GDB's ability to find yacc/lex sources, and include files,
7011 especially if you are debugging your program from a directory different from
7012 the one that contains your sources.
7014 We also fixed a bug which caused difficulty with listing and setting
7015 breakpoints in include files which contain C code. (In the past, you had to
7016 try twice in order to list an include file that you hadn't looked at before.)
7018 * Interesting infernals change
7020 GDB now deals with arbitrary numbers of sections, where the symbols for each
7021 section must be relocated relative to that section's landing place in the
7022 target's address space. This work was needed to support ELF with embedded
7023 stabs used by Solaris-2.0.
7025 * Bug fixes (of course!)
7027 There have been loads of fixes for the following things:
7028 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7029 i960, stabs, DOS(GO32), procfs, etc...
7031 See the ChangeLog for details.
7033 *** Changes in GDB-4.5:
7035 * New machines supported (host and target)
7037 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7039 SGI Irix-4.x mips-sgi-irix4 or iris4
7041 * New malloc package
7043 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7044 Mmalloc is capable of handling mutiple heaps of memory. It is also
7045 capable of saving a heap to a file, and then mapping it back in later.
7046 This can be used to greatly speedup the startup of GDB by using a
7047 pre-parsed symbol table which lives in a mmalloc managed heap. For
7048 more details, please read mmalloc/mmalloc.texi.
7052 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7053 'help info proc' for details.
7055 * MIPS ecoff symbol table format
7057 The code that reads MIPS symbol table format is now supported on all hosts.
7058 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7061 * File name changes for MS-DOS
7063 Many files in the config directories have been renamed to make it easier to
7064 support GDB on MS-DOSe systems (which have very restrictive file name
7065 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7066 environment) is close to working but has some remaining problems. Note
7067 that debugging of DOS programs is not supported, due to limitations
7068 in the ``operating system'', but it can be used to host cross-debugging.
7070 * Cross byte order fixes
7072 Many fixes have been made to support cross debugging of Sparc and MIPS
7073 targets from hosts whose byte order differs.
7075 * New -mapped and -readnow options
7077 If memory-mapped files are available on your system through the 'mmap'
7078 system call, you can use the -mapped option on the `file' or
7079 `symbol-file' commands to cause GDB to write the symbols from your
7080 program into a reusable file. If the program you are debugging is
7081 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7082 Future GDB debugging sessions will notice the presence of this file,
7083 and will quickly map in symbol information from it, rather than reading
7084 the symbol table from the executable program. Using the '-mapped'
7085 option in a GDB `file' or `symbol-file' command has the same effect as
7086 starting GDB with the '-mapped' command-line option.
7088 You can cause GDB to read the entire symbol table immediately by using
7089 the '-readnow' option with any of the commands that load symbol table
7090 information (or on the GDB command line). This makes the command
7091 slower, but makes future operations faster.
7093 The -mapped and -readnow options are typically combined in order to
7094 build a `fred.syms' file that contains complete symbol information.
7095 A simple GDB invocation to do nothing but build a `.syms' file for future
7098 gdb -batch -nx -mapped -readnow programname
7100 The `.syms' file is specific to the host machine on which GDB is run.
7101 It holds an exact image of GDB's internal symbol table. It cannot be
7102 shared across multiple host platforms.
7104 * longjmp() handling
7106 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7107 siglongjmp() without losing control. This feature has not yet been ported to
7108 all systems. It currently works on many 386 platforms, all MIPS-based
7109 platforms (SGI, DECstation, etc), and Sun3/4.
7113 Preliminary work has been put in to support the new Solaris OS from Sun. At
7114 this time, it can control and debug processes, but it is not capable of
7119 As always, many many bug fixes. The major areas were with g++, and mipsread.
7120 People using the MIPS-based platforms should experience fewer mysterious
7121 crashes and trashed symbol tables.
7123 *** Changes in GDB-4.4:
7125 * New machines supported (host and target)
7127 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7129 BSD Reno on Vax vax-dec-bsd
7130 Ultrix on Vax vax-dec-ultrix
7132 * New machines supported (target)
7134 AMD 29000 embedded, using EBMON a29k-none-none
7138 GDB continues to improve its handling of C++. `References' work better.
7139 The demangler has also been improved, and now deals with symbols mangled as
7140 per the Annotated C++ Reference Guide.
7142 GDB also now handles `stabs' symbol information embedded in MIPS
7143 `ecoff' symbol tables. Since the ecoff format was not easily
7144 extensible to handle new languages such as C++, this appeared to be a
7145 good way to put C++ debugging info into MIPS binaries. This option
7146 will be supported in the GNU C compiler, version 2, when it is
7149 * New features for SVR4
7151 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7152 shared libraries. Debugging dynamically linked programs should present
7153 only minor differences from debugging statically linked programs.
7155 The `info proc' command will print out information about any process
7156 on an SVR4 system (including the one you are debugging). At the moment,
7157 it prints the address mappings of the process.
7159 If you bring up GDB on another SVR4 system, please send mail to
7160 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7162 * Better dynamic linking support in SunOS
7164 Reading symbols from shared libraries which contain debugging symbols
7165 now works properly. However, there remain issues such as automatic
7166 skipping of `transfer vector' code during function calls, which
7167 make it harder to debug code in a shared library, than to debug the
7168 same code linked statically.
7172 GDB is now using the latest `getopt' routines from the FSF. This
7173 version accepts the -- prefix for options with long names. GDB will
7174 continue to accept the old forms (-option and +option) as well.
7175 Various single letter abbreviations for options have been explicity
7176 added to the option table so that they won't get overshadowed in the
7177 future by other options that begin with the same letter.
7181 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7182 Many assorted bugs have been handled. Many more remain to be handled.
7183 See the various ChangeLog files (primarily in gdb and bfd) for details.
7186 *** Changes in GDB-4.3:
7188 * New machines supported (host and target)
7190 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7191 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7192 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7194 * Almost SCO Unix support
7196 We had hoped to support:
7197 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7198 (except for core file support), but we discovered very late in the release
7199 that it has problems with process groups that render gdb unusable. Sorry
7200 about that. I encourage people to fix it and post the fixes.
7202 * Preliminary ELF and DWARF support
7204 GDB can read ELF object files on System V Release 4, and can handle
7205 debugging records for C, in DWARF format, in ELF files. This support
7206 is preliminary. If you bring up GDB on another SVR4 system, please
7207 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7212 GDB now uses the latest `readline' library. One user-visible change
7213 is that two tabs will list possible command completions, which previously
7214 required typing M-? (meta-question mark, or ESC ?).
7218 The `stepi' bug that many of you noticed has been squashed.
7219 Many bugs in C++ have been handled. Many more remain to be handled.
7220 See the various ChangeLog files (primarily in gdb and bfd) for details.
7222 * State of the MIPS world (in case you wondered):
7224 GDB can understand the symbol tables emitted by the compilers
7225 supplied by most vendors of MIPS-based machines, including DEC. These
7226 symbol tables are in a format that essentially nobody else uses.
7228 Some versions of gcc come with an assembler post-processor called
7229 mips-tfile. This program is required if you want to do source-level
7230 debugging of gcc-compiled programs. I believe FSF does not ship
7231 mips-tfile with gcc version 1, but it will eventually come with gcc
7234 Debugging of g++ output remains a problem. g++ version 1.xx does not
7235 really support it at all. (If you're lucky, you should be able to get
7236 line numbers and stack traces to work, but no parameters or local
7237 variables.) With some work it should be possible to improve the
7240 When gcc version 2 is released, you will have somewhat better luck.
7241 However, even then you will get confusing results for inheritance and
7244 We will eventually provide full debugging of g++ output on
7245 DECstations. This will probably involve some kind of stabs-in-ecoff
7246 encapulation, but the details have not been worked out yet.
7249 *** Changes in GDB-4.2:
7251 * Improved configuration
7253 Only one copy of `configure' exists now, and it is not self-modifying.
7254 Porting BFD is simpler.
7258 The `step' and `next' commands now only stop at the first instruction
7259 of a source line. This prevents the multiple stops that used to occur
7260 in switch statements, for-loops, etc. `Step' continues to stop if a
7261 function that has debugging information is called within the line.
7265 Lots of small bugs fixed. More remain.
7267 * New host supported (not target)
7269 Intel 386 PC clone running Mach i386-none-mach
7272 *** Changes in GDB-4.1:
7274 * Multiple source language support
7276 GDB now has internal scaffolding to handle several source languages.
7277 It determines the type of each source file from its filename extension,
7278 and will switch expression parsing and number formatting to match the
7279 language of the function in the currently selected stack frame.
7280 You can also specifically set the language to be used, with
7281 `set language c' or `set language modula-2'.
7285 GDB now has preliminary support for the GNU Modula-2 compiler,
7286 currently under development at the State University of New York at
7287 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7288 continue through the fall of 1991 and into 1992.
7290 Other Modula-2 compilers are currently not supported, and attempting to
7291 debug programs compiled with them will likely result in an error as the
7292 symbol table is read. Feel free to work on it, though!
7294 There are hooks in GDB for strict type checking and range checking,
7295 in the `Modula-2 philosophy', but they do not currently work.
7299 GDB can now write to executable and core files (e.g. patch
7300 a variable's value). You must turn this switch on, specify
7301 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7302 by assigning a new value to a variable. Modifications take
7305 * Automatic SunOS shared library reading
7307 When you run your program, GDB automatically determines where its
7308 shared libraries (if any) have been loaded, and reads their symbols.
7309 The `share' command is no longer needed. This also works when
7310 examining core files.
7314 You can specify the number of lines that the `list' command shows.
7317 * New machines supported (host and target)
7319 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7320 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7321 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7323 * New hosts supported (not targets)
7325 IBM RT/PC: romp-ibm-aix or rtpc
7327 * New targets supported (not hosts)
7329 AMD 29000 embedded with COFF a29k-none-coff
7330 AMD 29000 embedded with a.out a29k-none-aout
7331 Ultracomputer remote kernel debug a29k-nyu-kern
7333 * New remote interfaces
7339 *** Changes in GDB-4.0:
7343 Wide output is wrapped at good places to make the output more readable.
7345 Gdb now supports cross-debugging from a host machine of one type to a
7346 target machine of another type. Communication with the target system
7347 is over serial lines. The ``target'' command handles connecting to the
7348 remote system; the ``load'' command will download a program into the
7349 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7350 also supports debugging of realtime processes running under VxWorks,
7351 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7352 stub on the target system.
7354 New CPUs supported include the AMD 29000 and Intel 960.
7356 GDB now reads object files and symbol tables via a ``binary file''
7357 library, which allows a single copy of GDB to debug programs of multiple
7358 object file types such as a.out and coff.
7360 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7361 refcard.dvi and refcard.ps are available to format it).
7364 * Control-Variable user interface simplified
7366 All variables that control the operation of the debugger can be set
7367 by the ``set'' command, and displayed by the ``show'' command.
7369 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7370 ``Show prompt'' produces the response:
7371 Gdb's prompt is new-gdb=>.
7373 What follows are the NEW set commands. The command ``help set'' will
7374 print a complete list of old and new set commands. ``help set FOO''
7375 will give a longer description of the variable FOO. ``show'' will show
7376 all of the variable descriptions and their current settings.
7378 confirm on/off: Enables warning questions for operations that are
7379 hard to recover from, e.g. rerunning the program while
7380 it is already running. Default is ON.
7382 editing on/off: Enables EMACS style command line editing
7383 of input. Previous lines can be recalled with
7384 control-P, the current line can be edited with control-B,
7385 you can search for commands with control-R, etc.
7388 history filename NAME: NAME is where the gdb command history
7389 will be stored. The default is .gdb_history,
7390 or the value of the environment variable
7393 history size N: The size, in commands, of the command history. The
7394 default is 256, or the value of the environment variable
7397 history save on/off: If this value is set to ON, the history file will
7398 be saved after exiting gdb. If set to OFF, the
7399 file will not be saved. The default is OFF.
7401 history expansion on/off: If this value is set to ON, then csh-like
7402 history expansion will be performed on
7403 command line input. The default is OFF.
7405 radix N: Sets the default radix for input and output. It can be set
7406 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7407 in the current radix, so "set radix 10" is always a no-op.
7409 height N: This integer value is the number of lines on a page. Default
7410 is 24, the current `stty rows'' setting, or the ``li#''
7411 setting from the termcap entry matching the environment
7414 width N: This integer value is the number of characters on a line.
7415 Default is 80, the current `stty cols'' setting, or the ``co#''
7416 setting from the termcap entry matching the environment
7419 Note: ``set screensize'' is obsolete. Use ``set height'' and
7420 ``set width'' instead.
7422 print address on/off: Print memory addresses in various command displays,
7423 such as stack traces and structure values. Gdb looks
7424 more ``symbolic'' if you turn this off; it looks more
7425 ``machine level'' with it on. Default is ON.
7427 print array on/off: Prettyprint arrays. New convenient format! Default
7430 print demangle on/off: Print C++ symbols in "source" form if on,
7433 print asm-demangle on/off: Same, for assembler level printouts
7436 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7439 * Support for Epoch Environment.
7441 The epoch environment is a version of Emacs v18 with windowing. One
7442 new command, ``inspect'', is identical to ``print'', except that if you
7443 are running in the epoch environment, the value is printed in its own
7447 * Support for Shared Libraries
7449 GDB can now debug programs and core files that use SunOS shared libraries.
7450 Symbols from a shared library cannot be referenced
7451 before the shared library has been linked with the program (this
7452 happens after you type ``run'' and before the function main() is entered).
7453 At any time after this linking (including when examining core files
7454 from dynamically linked programs), gdb reads the symbols from each
7455 shared library when you type the ``sharedlibrary'' command.
7456 It can be abbreviated ``share''.
7458 sharedlibrary REGEXP: Load shared object library symbols for files
7459 matching a unix regular expression. No argument
7460 indicates to load symbols for all shared libraries.
7462 info sharedlibrary: Status of loaded shared libraries.
7467 A watchpoint stops execution of a program whenever the value of an
7468 expression changes. Checking for this slows down execution
7469 tremendously whenever you are in the scope of the expression, but is
7470 quite useful for catching tough ``bit-spreader'' or pointer misuse
7471 problems. Some machines such as the 386 have hardware for doing this
7472 more quickly, and future versions of gdb will use this hardware.
7474 watch EXP: Set a watchpoint (breakpoint) for an expression.
7476 info watchpoints: Information about your watchpoints.
7478 delete N: Deletes watchpoint number N (same as breakpoints).
7479 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7480 enable N: Re-enables watchpoint number N (same as breakpoints).
7483 * C++ multiple inheritance
7485 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7488 * C++ exception handling
7490 Gdb now supports limited C++ exception handling. Besides the existing
7491 ability to breakpoint on an exception handler, gdb can breakpoint on
7492 the raising of an exception (before the stack is peeled back to the
7495 catch FOO: If there is a FOO exception handler in the dynamic scope,
7496 set a breakpoint to catch exceptions which may be raised there.
7497 Multiple exceptions (``catch foo bar baz'') may be caught.
7499 info catch: Lists all exceptions which may be caught in the
7500 current stack frame.
7503 * Minor command changes
7505 The command ``call func (arg, arg, ...)'' now acts like the print
7506 command, except it does not print or save a value if the function's result
7507 is void. This is similar to dbx usage.
7509 The ``up'' and ``down'' commands now always print the frame they end up
7510 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7511 frames without printing.
7513 * New directory command
7515 'dir' now adds directories to the FRONT of the source search path.
7516 The path starts off empty. Source files that contain debug information
7517 about the directory in which they were compiled can be found even
7518 with an empty path; Sun CC and GCC include this information. If GDB can't
7519 find your source file in the current directory, type "dir .".
7521 * Configuring GDB for compilation
7523 For normal use, type ``./configure host''. See README or gdb.texinfo
7526 GDB now handles cross debugging. If you are remotely debugging between
7527 two different machines, type ``./configure host -target=targ''.
7528 Host is the machine where GDB will run; targ is the machine
7529 where the program that you are debugging will run.