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 * New built-in convenience functions $_gdb_setting, $_gdb_setting_str,
15 $_gdb_maint_setting and $_gdb_maint_setting_str provide access to values
16 of the GDB settings and the GDB maintenance settings. They are handy
17 for changing the logic of user defined commands depending on the
20 * GDB now supports Thread Local Storage (TLS) variables on several
21 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
22 architectures require kernel changes. TLS is not yet supported for
23 amd64 and i386 process core dumps.
25 * Support for Pointer Authentication (PAC) on AArch64 Linux. Return
26 addresses that required unmasking are shown in the backtrace with the
29 * Two new convenience functions $_cimag and $_creal that extract the
30 imaginary and real parts respectively from complex numbers.
32 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
33 provide the exitcode or exit status of the shell commands launched by
34 GDB commands such as "shell", "pipe" and "make".
36 * The RX port now supports XML target descriptions.
38 * GDB now shows the Ada task names at more places, e.g. in task switching
41 * GDB can now be compiled with Python 3 on Windows.
43 * New convenience variable $_ada_exception holds the address of the
44 Ada exception being thrown. This is set by Ada-related catchpoints.
46 * GDB can now place breakpoints on nested functions and subroutines in
47 Fortran code. The '::' operator can be used between parent and
48 child scopes when placing breakpoints, for example:
50 (gdb) break outer_function::inner_function
52 The 'outer_function::' prefix is only needed if 'inner_function' is
53 not visible in the current scope.
55 * In addition to the system-wide gdbinit file, if configured with
56 --with-system-gdbinit-dir, GDB will now also load files in that directory
57 as system gdbinit files, unless the -nx or -n flag is provided. Files
58 with extensions .gdb, .py and .scm are supported as long as GDB was
59 compiled with support for that language.
63 ** The gdb.Value type has a new method 'format_string' which returns a
64 string representing the value. The formatting is controlled by the
65 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
66 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
67 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
69 ** gdb.Type has a new property 'objfile' which returns the objfile the
72 ** The frame information printed by the python frame filtering code
73 is now consistent with what the 'backtrace' command prints when
74 there are no filters, or when the 'backtrace' '-no-filters' option
77 ** The new function gdb.lookup_static_symbol can be used to look up
78 symbols with static linkage.
80 ** gdb.Objfile has new methods 'lookup_global_symbol' and
81 'lookup_static_symbol' to lookup a symbol from this objfile only.
83 ** gdb.Block now supports the dictionary syntax for accessing symbols in
84 this block (e.g. block['local_variable']).
88 | [COMMAND] | SHELL_COMMAND
89 | -d DELIM COMMAND DELIM SHELL_COMMAND
90 pipe [COMMAND] | SHELL_COMMAND
91 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
92 Executes COMMAND and sends its output to SHELL_COMMAND.
93 With no COMMAND, repeat the last executed command
94 and send its output to SHELL_COMMAND.
96 with SETTING [VALUE] [-- COMMAND]
97 w SETTING [VALUE] [-- COMMAND]
98 Temporarily set SETTING, run COMMAND, and restore SETTING.
99 Usage: with SETTING -- COMMAND
100 With no COMMAND, repeats the last executed command.
101 SETTING is any GDB setting you can change with the "set"
102 subcommands. For example, 'with language c -- print someobj'
103 temporarily switches to the C language in order to print someobj.
104 Settings can be combined: 'w lang c -- w print elements unlimited --
105 usercmd' switches to the C language and runs usercmd with no limit
106 of array elements to print.
108 maint with SETTING [VALUE] [-- COMMAND]
109 Like "with", but works with "maintenance set" settings.
111 set may-call-functions [on|off]
112 show may-call-functions
113 This controls whether GDB will attempt to call functions in
114 the program, such as with expressions in the print command. It
115 defaults to on. Calling functions in the program being debugged
116 can have undesired side effects. It is now possible to forbid
117 such function calls. If function calls are forbidden, GDB will throw
118 an error when a command (such as print expression) calls a function
121 set print finish [on|off]
123 This controls whether the `finish' command will display the value
124 that is returned by the current function. When `off', the value is
125 still entered into the value history, but it is not printed. The
130 Allows deeply nested structures to be simplified when printing by
131 replacing deeply nested parts (beyond the max-depth) with ellipses.
132 The default max-depth is 20, but this can be set to unlimited to get
133 the old behavior back.
135 set logging debugredirect [on|off]
136 By default, GDB debug output will go to both the terminal and the logfile.
137 Set if you want debug output to go only to the log file.
139 set style title foreground COLOR
140 set style title background COLOR
141 set style title intensity VALUE
142 Control the styling of titles.
144 set style highlight foreground COLOR
145 set style highlight background COLOR
146 set style highlight intensity VALUE
147 Control the styling of highlightings.
149 maint set test-settings KIND
150 maint show test-settings KIND
151 A set of commands used by the testsuite for exercising the settings
154 set print frame-info [short-location|location|location-and-address
155 |source-and-location|source-line|auto]
156 show print frame-info
157 This controls what frame information is printed by the commands printing
158 a frame. This setting will e.g. influence the behaviour of 'backtrace',
159 'frame', 'stepi'. The python frame filtering also respect this setting.
160 The 'backtrace' '-frame-info' option can override this global setting.
162 info modules [-q] [REGEXP]
163 Return a list of Fortran modules matching REGEXP, or all modules if
169 The "help" command uses the title style to enhance the
170 readibility of its output by styling the classes and
174 Similarly to "help", the "apropos" command also uses the
175 title style for the command names. "apropos" accepts now
176 a flag "-v" (verbose) to show the full documentation
177 of matching commands and to use the highlight style to mark
178 the documentation parts matching REGEXP.
182 The GDB printf and eval commands can now print C-style and Ada-style
183 string convenience variables without calling functions in the program.
184 This allows to do formatted printing of strings without having
185 a running inferior, or when debugging a core dump.
187 info sources [-dirname | -basename] [--] [REGEXP]
188 This command has now optional arguments to only print the files
189 whose names match REGEXP. The arguments -dirname and -basename
190 allow to restrict matching respectively to the dirname and basename
194 The "show style" and its subcommands are now styling
195 a style name in their output using its own style, to help
196 the user visualize the different styles.
198 set print frame-arguments
199 The new value 'presence' indicates to only indicate the presence of
200 arguments using ..., instead of printing argument names and values.
202 set print raw-frame-arguments
203 show print raw-frame-arguments
205 These commands replace the similarly-named "set/show print raw
206 frame-arguments" commands (now with a dash instead of a space). The
207 old commands are now deprecated and may be removed in a future
210 maint test-options require-delimiter
211 maint test-options unknown-is-error
212 maint test-options unknown-is-operand
213 maint show test-options-completion-result
214 Commands used by the testsuite to validate the command options
217 focus, winheight, +, -, >, <
218 These commands are now case-sensitive.
220 * New command options, command completion
222 GDB now has a standard infrastructure to support dash-style command
223 options ('-OPT'). One benefit is that commands that use it can
224 easily support completion of command line arguments. Try "CMD
225 -[TAB]" or "help CMD" to find options supported by a command. Over
226 time, we intend to migrate most commands to this infrastructure. A
227 number of commands got support for new command options in this
230 ** The "print" and "compile print" commands now support a number of
231 options that allow overriding relevant global print settings as
232 set by "set print" subcommands:
236 -array-indexes [on|off]
237 -elements NUMBER|unlimited
241 -repeats NUMBER|unlimited
242 -static-members [on|off]
247 Note that because the "print"/"compile print" commands accept
248 arbitrary expressions which may look like options (including
249 abbreviations), if you specify any command option, then you must
250 use a double dash ("--") to mark the end of argument processing.
252 ** The "backtrace" command now supports a number of options that
253 allow overriding relevant global print settings as set by "set
254 backtrace" and "set print" subcommands:
256 -entry-values no|only|preferred|if-needed|both|compact|default
257 -frame-arguments all|scalars|none
258 -raw-frame-arguments [on|off]
259 -frame-info auto|source-line|location|source-and-location
260 |location-and-address|short-location
264 In addition, the full/no-filters/hide qualifiers are now also
265 exposed as command options too:
271 ** The "frame apply", "tfaas" and "faas" commands similarly now
272 support the following options:
277 ** The new "info sources" options -dirname and -basename options
278 are using the standard '-OPT' infrastructure.
280 All options above can also be abbreviated. The argument of boolean
281 (on/off) options can be 0/1 too, and also the argument is assumed
282 "on" if omitted. This allows writing compact command invocations,
285 (gdb) p -r -p -o 0 -- *myptr
287 The above is equivalent to:
289 (gdb) print -raw -pretty -object off -- *myptr
291 ** The "info types" command now supports the '-q' flag to disable
292 printing of some header information in a similar fashion to "info
293 variables" and "info functions".
295 ** The "info variables", "info functions", and "whereis" commands
296 now take a '-n' flag that excludes non-debug symbols (symbols
297 from the symbol table, not from the debug info such as DWARF)
300 * Completion improvements
302 ** GDB can now complete the options of the "thread apply all" and
303 "taas" commands, and their "-ascending" option can now be
306 ** GDB can now complete the options of the "info threads", "info
307 functions", "info variables", "info locals", and "info args"
310 ** GDB can now complete the options of the "compile file" and
311 "compile code" commands. The "compile file" command now
312 completes on filenames.
314 ** GDB can now complete the backtrace command's
315 "full/no-filters/hide" qualifiers.
317 * In settings, you can now abbreviate "unlimited".
319 E.g., "set print elements u" is now equivalent to "set print
325 This lists all the possible completions for the rest of the line, if it
326 were to be given as a command itself. This is intended for use by MI
327 frontends in cases when separate CLI and MI channels cannot be used.
329 -catch-throw, -catch-rethrow, and -catch-catch
330 These can be used to catch C++ exceptions in a similar fashion to
331 the CLI commands 'catch throw', 'catch rethrow', and 'catch catch'.
335 ** The default version of the MI interpreter is now 3 (-i=mi3).
337 ** The output of information about multi-location breakpoints (which is
338 syntactically incorrect in MI 2) has changed in MI 3. This affects
339 the following commands and events:
343 - =breakpoint-created
344 - =breakpoint-modified
346 The -fix-multi-location-breakpoint-output command can be used to enable
347 this behavior with previous MI versions.
349 ** Backtraces and frames include a new optional field addr_flags which is
350 given after the addr field. On AArch64 this contains PAC if the address
351 has been masked in the frame. On all other targets the field is not
356 The testsuite now creates the files gdb.cmd (containing the arguments
357 used to launch GDB) and gdb.in (containing all the commands sent to
358 GDB) in the output directory for each test script. Multiple invocations
359 are appended with .1, .2, .3 etc.
361 * Building GDB and GDBserver now requires GNU make >= 3.82.
363 Using another implementation of the make program or an earlier version of
364 GNU make to build GDB or GDBserver is not supported.
366 * Building GDB now requires GNU readline >= 7.0.
368 GDB now bundles GNU readline 8.0, but if you choose to use
369 --with-system-readline, only readline >= 7.0 can be used.
371 * The TUI SingleKey keymap is now named "SingleKey". This can be used
372 from .inputrc to bind keys in this keymap. This feature is only
373 available when gdb is built against GNU readline 8.0 or later.
375 * Removed targets and native configurations
377 GDB no longer supports debugging the Cell Broadband Engine. This includes
378 both debugging standalone Cell/B.E. SPU applications and integrated debugging
379 of Cell/B.E. applications that use both the PPU and SPU architectures.
385 *** Changes in GDB 8.3
387 * GDB and GDBserver now support access to additional registers on
388 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
391 * GDB now has experimental support for the compilation and injection of
392 C++ source code into the inferior. This beta release does not include
393 support for several language features, such as templates, constructors,
396 This feature requires GCC 7.1 or higher built with libcp1.so
399 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
400 can be passed using the '[ADDRESS]:PORT' notation, or the regular
401 'ADDRESS:PORT' method.
403 * DWARF index cache: GDB can now automatically save indices of DWARF
404 symbols on disk to speed up further loading of the same binaries.
406 * Ada task switching is now supported on aarch64-elf targets when
407 debugging a program using the Ravenscar Profile. For more information,
408 see the "Tasking Support when using the Ravenscar Profile" section
409 in the GDB user manual.
411 * GDB in batch mode now exits with status 1 if the last command to be
414 * The RISC-V target now supports target descriptions.
416 * System call catchpoints now support system call aliases on FreeBSD.
417 When the ABI of a system call changes in FreeBSD, this is
418 implemented by leaving a compatibility system call using the old ABI
419 at the existing number and allocating a new system call number for
420 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
421 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
422 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
423 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
424 so that a system call catchpoint for the 'kevent' system call will
425 catch invocations of both the 'kevent' and 'freebsd11_kevent'
426 binaries. This ensures that 'kevent' system calls are caught for
427 binaries using either the old or new ABIs.
429 * Terminal styling is now available for the CLI and the TUI. GNU
430 Source Highlight can additionally be used to provide styling of
431 source code snippets. See the "set style" commands, below, for more
434 * Removed support for old demangling styles arm, edg, gnu, hp and
439 set debug compile-cplus-types
440 show debug compile-cplus-types
441 Control the display of debug output about type conversion in the
442 C++ compile feature. Commands have no effect while compiliong
447 Control whether debug output about files/functions skipping is
450 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
451 Apply a command to some frames.
452 FLAG arguments allow to control what output to produce and how to handle
453 errors raised when applying COMMAND to a frame.
456 Apply a command to all threads (ignoring errors and empty output).
457 Shortcut for 'thread apply all -s COMMAND'.
460 Apply a command to all frames (ignoring errors and empty output).
461 Shortcut for 'frame apply all -s COMMAND'.
464 Apply a command to all frames of all threads (ignoring errors and empty
466 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
468 maint set dwarf unwinders (on|off)
469 maint show dwarf unwinders
470 Control whether DWARF unwinders can be used.
473 Display a list of open files for a process.
477 Changes to the "frame", "select-frame", and "info frame" CLI commands.
478 These commands all now take a frame specification which
479 is either a frame level, or one of the keywords 'level', 'address',
480 'function', or 'view' followed by a parameter. Selecting a frame by
481 address, or viewing a frame outside the current backtrace now
482 requires the use of a keyword. Selecting a frame by level is
483 unchanged. The MI comment "-stack-select-frame" is unchanged.
485 target remote FILENAME
486 target extended-remote FILENAME
487 If FILENAME is a Unix domain socket, GDB will attempt to connect
488 to this socket instead of opening FILENAME as a character device.
490 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
491 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
492 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
493 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
494 These commands can now print only the searched entities
495 matching the provided regexp(s), giving a condition
496 on the entity names or entity types. The flag -q disables
497 printing headers or informations messages.
503 These commands now determine the syntax for the shown entities
504 according to the language chosen by `set language'. In particular,
505 `set language auto' means to automatically choose the language of
508 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
509 The 'thread apply' command accepts new FLAG arguments.
510 FLAG arguments allow to control what output to produce and how to handle
511 errors raised when applying COMMAND to a thread.
513 set tui tab-width NCHARS
514 show tui tab-width NCHARS
515 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
517 set style enabled [on|off]
519 Enable or disable terminal styling. Styling is enabled by default
520 on most hosts, but disabled by default when in batch mode.
522 set style sources [on|off]
524 Enable or disable source code styling. Source code styling is
525 enabled by default, but only takes effect if styling in general is
526 enabled, and if GDB was linked with GNU Source Highlight.
528 set style filename foreground COLOR
529 set style filename background COLOR
530 set style filename intensity VALUE
531 Control the styling of file names.
533 set style function foreground COLOR
534 set style function background COLOR
535 set style function intensity VALUE
536 Control the styling of function names.
538 set style variable foreground COLOR
539 set style variable background COLOR
540 set style variable intensity VALUE
541 Control the styling of variable names.
543 set style address foreground COLOR
544 set style address background COLOR
545 set style address intensity VALUE
546 Control the styling of addresses.
550 ** The '-data-disassemble' MI command now accepts an '-a' option to
551 disassemble the whole function surrounding the given program
552 counter value or function name. Support for this feature can be
553 verified by using the "-list-features" command, which should
554 contain "data-disassemble-a-option".
556 ** Command responses and notifications that include a frame now include
557 the frame's architecture in a new "arch" attribute.
559 * New native configurations
561 GNU/Linux/RISC-V riscv*-*-linux*
562 FreeBSD/riscv riscv*-*-freebsd*
566 GNU/Linux/RISC-V riscv*-*-linux*
568 CSKY GNU/LINUX csky*-*-linux
569 FreeBSD/riscv riscv*-*-freebsd*
571 GNU/Linux/OpenRISC or1k*-*-linux*
575 GDB no longer supports native debugging on versions of MS-Windows
580 ** GDB no longer supports Python versions less than 2.6.
582 ** The gdb.Inferior type has a new 'progspace' property, which is the program
583 space associated to that inferior.
585 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
586 of objfiles associated to that program space.
588 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
589 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
592 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
593 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
594 correct and did not work properly.
596 ** The gdb.Value type has a new constructor, which is used to construct a
597 gdb.Value from a Python buffer object and a gdb.Type.
603 Enable or disable the undefined behavior sanitizer. This is
604 disabled by default, but passing --enable-ubsan=yes or
605 --enable-ubsan=auto to configure will enable it. Enabling this can
606 cause a performance penalty. The undefined behavior sanitizer was
607 first introduced in GCC 4.9.
609 *** Changes in GDB 8.2
611 * The 'set disassembler-options' command now supports specifying options
614 * The 'symbol-file' command now accepts an '-o' option to add a relative
615 offset to all sections.
617 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
618 a relative offset to all sections, but it allows to override the load
619 address of individual sections using '-s'.
621 * The 'add-symbol-file' command no longer requires the second argument
622 (address of the text section).
624 * The endianness used with the 'set endian auto' mode in the absence of
625 an executable selected for debugging is now the last endianness chosen
626 either by one of the 'set endian big' and 'set endian little' commands
627 or by inferring from the last executable used, rather than the startup
630 * The pager now allows a "c" response, meaning to disable the pager
631 for the rest of the current command.
633 * The commands 'info variables/functions/types' now show the source line
634 numbers of symbol definitions when available.
636 * 'info proc' now works on running processes on FreeBSD systems and core
637 files created on FreeBSD systems.
639 * C expressions can now use _Alignof, and C++ expressions can now use
642 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
643 the vector length while the process is running.
649 Control display of debugging info regarding the FreeBSD native target.
651 set|show varsize-limit
652 This new setting allows the user to control the maximum size of Ada
653 objects being printed when those objects have a variable type,
654 instead of that maximum size being hardcoded to 65536 bytes.
656 set|show record btrace cpu
657 Controls the processor to be used for enabling errata workarounds for
660 maint check libthread-db
661 Run integrity checks on the current inferior's thread debugging
664 maint set check-libthread-db (on|off)
665 maint show check-libthread-db
666 Control whether to run integrity checks on inferior specific thread
667 debugging libraries as they are loaded. The default is not to
672 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
674 ** The commands attached to a breakpoint can be set by assigning to
675 the breakpoint's "commands" field.
677 ** gdb.execute can now execute multi-line gdb commands.
679 ** The new functions gdb.convenience_variable and
680 gdb.set_convenience_variable can be used to get and set the value
681 of convenience variables.
683 ** A gdb.Parameter will no longer print the "set" help text on an
684 ordinary "set"; instead by default a "set" will be silent unless
685 the get_set_string method returns a non-empty string.
689 RiscV ELF riscv*-*-elf
691 * Removed targets and native configurations
693 m88k running OpenBSD m88*-*-openbsd*
694 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
695 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
696 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
698 * Aarch64/Linux hardware watchpoints improvements
700 Hardware watchpoints on unaligned addresses are now properly
701 supported when running Linux kernel 4.10 or higher: read and access
702 watchpoints are no longer spuriously missed, and all watchpoints
703 lengths between 1 and 8 bytes are supported. On older kernels,
704 watchpoints set on unaligned addresses are no longer missed, with
705 the tradeoff that there is a possibility of false hits being
710 --enable-codesign=CERT
711 This can be used to invoke "codesign -s CERT" after building gdb.
712 This option is useful on macOS, where code signing is required for
713 gdb to work properly.
715 --disable-gdbcli has been removed
716 This is now silently accepted, but does nothing.
718 *** Changes in GDB 8.1
720 * GDB now supports dynamically creating arbitrary register groups specified
721 in XML target descriptions. This allows for finer grain grouping of
722 registers on systems with a large amount of registers.
724 * The 'ptype' command now accepts a '/o' flag, which prints the
725 offsets and sizes of fields in a struct, like the pahole(1) tool.
727 * New "--readnever" command line option instructs GDB to not read each
728 symbol file's symbolic debug information. This makes startup faster
729 but at the expense of not being able to perform symbolic debugging.
730 This option is intended for use cases where symbolic debugging will
731 not be used, e.g., when you only need to dump the debuggee's core.
733 * GDB now uses the GNU MPFR library, if available, to emulate target
734 floating-point arithmetic during expression evaluation when the target
735 uses different floating-point formats than the host. At least version
736 3.1 of GNU MPFR is required.
738 * GDB now supports access to the guarded-storage-control registers and the
739 software-based guarded-storage broadcast control registers on IBM z14.
741 * On Unix systems, GDB now supports transmitting environment variables
742 that are to be set or unset to GDBserver. These variables will
743 affect the environment to be passed to the remote inferior.
745 To inform GDB of environment variables that are to be transmitted to
746 GDBserver, use the "set environment" command. Only user set
747 environment variables are sent to GDBserver.
749 To inform GDB of environment variables that are to be unset before
750 the remote inferior is started by the GDBserver, use the "unset
751 environment" command.
753 * Completion improvements
755 ** GDB can now complete function parameters in linespecs and
756 explicit locations without quoting. When setting breakpoints,
757 quoting around functions names to help with TAB-completion is
758 generally no longer necessary. For example, this now completes
761 (gdb) b function(in[TAB]
762 (gdb) b function(int)
764 Related, GDB is no longer confused with completing functions in
765 C++ anonymous namespaces:
768 (gdb) b (anonymous namespace)::[TAB][TAB]
769 (anonymous namespace)::a_function()
770 (anonymous namespace)::b_function()
772 ** GDB now has much improved linespec and explicit locations TAB
773 completion support, that better understands what you're
774 completing and offers better suggestions. For example, GDB no
775 longer offers data symbols as possible completions when you're
776 setting a breakpoint.
778 ** GDB now TAB-completes label symbol names.
780 ** The "complete" command now mimics TAB completion accurately.
782 * New command line options (gcore)
785 Dump all memory mappings.
787 * Breakpoints on C++ functions are now set on all scopes by default
789 By default, breakpoints on functions/methods are now interpreted as
790 specifying all functions with the given name ignoring missing
791 leading scopes (namespaces and classes).
793 For example, assuming a C++ program with symbols named:
798 both commands "break func()" and "break B::func()" set a breakpoint
801 You can use the new flag "-qualified" to override this. This makes
802 GDB interpret the specified function name as a complete
803 fully-qualified name instead. For example, using the same C++
804 program, the "break -q B::func" command sets a breakpoint on
805 "B::func", only. A parameter has been added to the Python
806 gdb.Breakpoint constructor to achieve the same result when creating
807 a breakpoint from Python.
809 * Breakpoints on functions marked with C++ ABI tags
811 GDB can now set breakpoints on functions marked with C++ ABI tags
812 (e.g., [abi:cxx11]). See here for a description of ABI tags:
813 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
815 Functions with a C++11 abi tag are demangled/displayed like this:
817 function[abi:cxx11](int)
820 You can now set a breakpoint on such functions simply as if they had
823 (gdb) b function(int)
825 Or if you need to disambiguate between tags, like:
827 (gdb) b function[abi:other_tag](int)
829 Tab completion was adjusted accordingly as well.
833 ** New events gdb.new_inferior, gdb.inferior_deleted, and
834 gdb.new_thread are emitted. See the manual for further
835 description of these.
837 ** A new function, "gdb.rbreak" has been added to the Python API.
838 This function allows the setting of a large number of breakpoints
839 via a regex pattern in Python. See the manual for further details.
841 ** Python breakpoints can now accept explicit locations. See the
842 manual for a further description of this feature.
845 * New features in the GDB remote stub, GDBserver
847 ** GDBserver is now able to start inferior processes with a
848 specified initial working directory.
850 The user can set the desired working directory to be used from
851 GDB using the new "set cwd" command.
853 ** New "--selftest" command line option runs some GDBserver self
854 tests. These self tests are disabled in releases.
856 ** On Unix systems, GDBserver now does globbing expansion and variable
857 substitution in inferior command line arguments.
859 This is done by starting inferiors using a shell, like GDB does.
860 See "set startup-with-shell" in the user manual for how to disable
861 this from GDB when using "target extended-remote". When using
862 "target remote", you can disable the startup with shell by using the
863 new "--no-startup-with-shell" GDBserver command line option.
865 ** On Unix systems, GDBserver now supports receiving environment
866 variables that are to be set or unset from GDB. These variables
867 will affect the environment to be passed to the inferior.
869 * When catching an Ada exception raised with a message, GDB now prints
870 the message in the catchpoint hit notification. In GDB/MI mode, that
871 information is provided as an extra field named "exception-message"
872 in the *stopped notification.
874 * Trait objects can now be inspected When debugging Rust code. This
875 requires compiler support which will appear in Rust 1.24.
879 QEnvironmentHexEncoded
880 Inform GDBserver of an environment variable that is to be passed to
881 the inferior when starting it.
884 Inform GDBserver of an environment variable that is to be unset
885 before starting the remote inferior.
888 Inform GDBserver that the environment should be reset (i.e.,
889 user-set environment variables should be unset).
892 Indicates whether the inferior must be started with a shell or not.
895 Tell GDBserver that the inferior to be started should use a specific
898 * The "maintenance print c-tdesc" command now takes an optional
899 argument which is the file name of XML target description.
901 * The "maintenance selftest" command now takes an optional argument to
902 filter the tests to be run.
904 * The "enable", and "disable" commands now accept a range of
905 breakpoint locations, e.g. "enable 1.3-5".
910 Set and show the current working directory for the inferior.
913 Set and show compilation command used for compiling and injecting code
914 with the 'compile' commands.
916 set debug separate-debug-file
917 show debug separate-debug-file
918 Control the display of debug output about separate debug file search.
920 set dump-excluded-mappings
921 show dump-excluded-mappings
922 Control whether mappings marked with the VM_DONTDUMP flag should be
923 dumped when generating a core file.
926 List the registered selftests.
929 Start the debugged program stopping at the first instruction.
932 Control display of debugging messages related to OpenRISC targets.
934 set|show print type nested-type-limit
935 Set and show the limit of nesting level for nested types that the
936 type printer will show.
938 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
941 * Safer/improved support for debugging with no debug info
943 GDB no longer assumes functions with no debug information return
946 This means that GDB now refuses to call such functions unless you
947 tell it the function's type, by either casting the call to the
948 declared return type, or by casting the function to a function
949 pointer of the right type, and calling that:
951 (gdb) p getenv ("PATH")
952 'getenv' has unknown return type; cast the call to its declared return type
953 (gdb) p (char *) getenv ("PATH")
954 $1 = 0x7fffffffe "/usr/local/bin:/"...
955 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
956 $2 = 0x7fffffffe "/usr/local/bin:/"...
958 Similarly, GDB no longer assumes that global variables with no debug
959 info have type 'int', and refuses to print the variable's value
960 unless you tell it the variable's type:
963 'var' has unknown type; cast it to its declared type
967 * New native configurations
969 FreeBSD/aarch64 aarch64*-*-freebsd*
970 FreeBSD/arm arm*-*-freebsd*
974 FreeBSD/aarch64 aarch64*-*-freebsd*
975 FreeBSD/arm arm*-*-freebsd*
976 OpenRISC ELF or1k*-*-elf
978 * Removed targets and native configurations
980 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
982 *** Changes in GDB 8.0
984 * GDB now supports access to the PKU register on GNU/Linux. The register is
985 added by the Memory Protection Keys for Userspace feature which will be
986 available in future Intel CPUs.
988 * GDB now supports C++11 rvalue references.
992 ** New functions to start, stop and access a running btrace recording.
993 ** Rvalue references are now supported in gdb.Type.
995 * GDB now supports recording and replaying rdrand and rdseed Intel 64
998 * Building GDB and GDBserver now requires a C++11 compiler.
1000 For example, GCC 4.8 or later.
1002 It is no longer possible to build GDB or GDBserver with a C
1003 compiler. The --disable-build-with-cxx configure option has been
1006 * Building GDB and GDBserver now requires GNU make >= 3.81.
1008 It is no longer supported to build GDB or GDBserver with another
1009 implementation of the make program or an earlier version of GNU make.
1011 * Native debugging on MS-Windows supports command-line redirection
1013 Command-line arguments used for starting programs on MS-Windows can
1014 now include redirection symbols supported by native Windows shells,
1015 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
1016 as "run", "start", and "set args", as well as the corresponding MI
1019 * Support for thread names on MS-Windows.
1021 GDB now catches and handles the special exception that programs
1022 running on MS-Windows use to assign names to threads in the
1025 * Support for Java programs compiled with gcj has been removed.
1027 * User commands now accept an unlimited number of arguments.
1028 Previously, only up to 10 was accepted.
1030 * The "eval" command now expands user-defined command arguments.
1032 This makes it easier to process a variable number of arguments:
1037 eval "print $arg%d", $i
1042 * Target descriptions can now describe registers for sparc32 and sparc64.
1044 * GDB now supports DWARF version 5 (debug information format).
1045 Its .debug_names index is not yet supported.
1047 * New native configurations
1049 FreeBSD/mips mips*-*-freebsd
1053 Synopsys ARC arc*-*-elf32
1054 FreeBSD/mips mips*-*-freebsd
1056 * Removed targets and native configurations
1058 Alpha running FreeBSD alpha*-*-freebsd*
1059 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
1064 Erases all the flash memory regions reported by the target.
1066 maint print arc arc-instruction address
1067 Print internal disassembler information about instruction at a given address.
1071 set disassembler-options
1072 show disassembler-options
1073 Controls the passing of target specific information to the disassembler.
1074 If it is necessary to specify more than one disassembler option then
1075 multiple options can be placed together into a comma separated list.
1076 The default value is the empty string. Currently, the only supported
1077 targets are ARM, PowerPC and S/390.
1082 Erases all the flash memory regions reported by the target. This is
1083 equivalent to the CLI command flash-erase.
1085 -file-list-shared-libraries
1086 List the shared libraries in the program. This is
1087 equivalent to the CLI command "info shared".
1090 Catchpoints stopping the program when Ada exceptions are
1091 handled. This is equivalent to the CLI command "catch handlers".
1093 *** Changes in GDB 7.12
1095 * GDB and GDBserver now build with a C++ compiler by default.
1097 The --enable-build-with-cxx configure option is now enabled by
1098 default. One must now explicitly configure with
1099 --disable-build-with-cxx in order to build with a C compiler. This
1100 option will be removed in a future release.
1102 * GDBserver now supports recording btrace without maintaining an active
1105 * GDB now supports a negative repeat count in the 'x' command to examine
1106 memory backward from the given address. For example:
1109 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
1110 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
1111 (gdb) x/-5i 0x0000000000400580
1112 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
1113 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
1114 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
1115 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
1116 0x40057b <main(int, char**)+25>:
1117 callq 0x400536 <Func1(int, char const*)>
1119 * Fortran: Support structures with fields of dynamic types and
1120 arrays of dynamic types.
1122 * The symbol dumping maintenance commands have new syntax.
1123 maint print symbols [-pc address] [--] [filename]
1124 maint print symbols [-objfile objfile] [-source source] [--] [filename]
1125 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
1126 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
1127 maint print msymbols [-objfile objfile] [--] [filename]
1129 * GDB now supports multibit bitfields and enums in target register
1132 * New Python-based convenience function $_as_string(val), which returns
1133 the textual representation of a value. This function is especially
1134 useful to obtain the text label of an enum value.
1136 * Intel MPX bound violation handling.
1138 Segmentation faults caused by a Intel MPX boundary violation
1139 now display the kind of violation (upper or lower), the memory
1140 address accessed and the memory bounds, along with the usual
1141 signal received and code location.
1145 Program received signal SIGSEGV, Segmentation fault
1146 Upper bound violation while accessing address 0x7fffffffc3b3
1147 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
1148 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
1150 * Rust language support.
1151 GDB now supports debugging programs written in the Rust programming
1152 language. See https://www.rust-lang.org/ for more information about
1155 * Support for running interpreters on specified input/output devices
1157 GDB now supports a new mechanism that allows frontends to provide
1158 fully featured GDB console views, as a better alternative to
1159 building such views on top of the "-interpreter-exec console"
1160 command. See the new "new-ui" command below. With that command,
1161 frontends can now start GDB in the traditional command-line mode
1162 running in an embedded terminal emulator widget, and create a
1163 separate MI interpreter running on a specified i/o device. In this
1164 way, GDB handles line editing, history, tab completion, etc. in the
1165 console all by itself, and the GUI uses the separate MI interpreter
1166 for its own control and synchronization, invisible to the command
1169 * The "catch syscall" command catches groups of related syscalls.
1171 The "catch syscall" command now supports catching a group of related
1172 syscalls using the 'group:' or 'g:' prefix.
1177 skip -gfile file-glob-pattern
1178 skip -function function
1179 skip -rfunction regular-expression
1180 A generalized form of the skip command, with new support for
1181 glob-style file names and regular expressions for function names.
1182 Additionally, a file spec and a function spec may now be combined.
1184 maint info line-table REGEXP
1185 Display the contents of GDB's internal line table data struture.
1188 Run any GDB unit tests that were compiled in.
1191 Start a new user interface instance running INTERP as interpreter,
1192 using the TTY file for input/output.
1196 ** gdb.Breakpoint objects have a new attribute "pending", which
1197 indicates whether the breakpoint is pending.
1198 ** Three new breakpoint-related events have been added:
1199 gdb.breakpoint_created, gdb.breakpoint_modified, and
1200 gdb.breakpoint_deleted.
1202 signal-event EVENTID
1203 Signal ("set") the given MS-Windows event object. This is used in
1204 conjunction with the Windows JIT debugging (AeDebug) support, where
1205 the OS suspends a crashing process until a debugger can attach to
1206 it. Resuming the crashing process, in order to debug it, is done by
1207 signalling an event.
1209 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
1210 was added in GDBserver, including JIT compiling fast tracepoint's
1211 conditional expression bytecode into native code.
1213 * Support for various remote target protocols and ROM monitors has
1216 target m32rsdi Remote M32R debugging over SDI
1217 target mips MIPS remote debugging protocol
1218 target pmon PMON ROM monitor
1219 target ddb NEC's DDB variant of PMON for Vr4300
1220 target rockhopper NEC RockHopper variant of PMON
1221 target lsi LSI variant of PMO
1223 * Support for tracepoints and fast tracepoints on powerpc-linux,
1224 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
1225 including JIT compiling fast tracepoint's conditional expression
1226 bytecode into native code.
1228 * MI async record =record-started now includes the method and format used for
1229 recording. For example:
1231 =record-started,thread-group="i1",method="btrace",format="bts"
1233 * MI async record =thread-selected now includes the frame field. For example:
1235 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
1239 Andes NDS32 nds32*-*-elf
1241 *** Changes in GDB 7.11
1243 * GDB now supports debugging kernel-based threads on FreeBSD.
1245 * Per-inferior thread numbers
1247 Thread numbers are now per inferior instead of global. If you're
1248 debugging multiple inferiors, GDB displays thread IDs using a
1249 qualified INF_NUM.THR_NUM form. For example:
1253 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
1254 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1255 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1256 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1258 As consequence, thread numbers as visible in the $_thread
1259 convenience variable and in Python's InferiorThread.num attribute
1260 are no longer unique between inferiors.
1262 GDB now maintains a second thread ID per thread, referred to as the
1263 global thread ID, which is the new equivalent of thread numbers in
1264 previous releases. See also $_gthread below.
1266 For backwards compatibility, MI's thread IDs always refer to global
1269 * Commands that accept thread IDs now accept the qualified
1270 INF_NUM.THR_NUM form as well. For example:
1273 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1276 * In commands that accept a list of thread IDs, you can now refer to
1277 all threads of an inferior using a star wildcard. GDB accepts
1278 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1279 refer to all threads of the current inferior. For example, "info
1282 * You can use "info threads -gid" to display the global thread ID of
1285 * The new convenience variable $_gthread holds the global number of
1288 * The new convenience variable $_inferior holds the number of the
1291 * GDB now displays the ID and name of the thread that hit a breakpoint
1292 or received a signal, if your program is multi-threaded. For
1295 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1296 Thread 1 "main" received signal SIGINT, Interrupt.
1298 * Record btrace now supports non-stop mode.
1300 * Support for tracepoints on aarch64-linux was added in GDBserver.
1302 * The 'record instruction-history' command now indicates speculative execution
1303 when using the Intel Processor Trace recording format.
1305 * GDB now allows users to specify explicit locations, bypassing
1306 the linespec parser. This feature is also available to GDB/MI
1309 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1310 GDB now is able to debug both AArch64 applications and ARM applications
1313 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1314 including JIT compiling fast tracepoint's conditional expression bytecode
1317 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1319 * "info threads", "info inferiors", "info display", "info checkpoints"
1320 and "maint info program-spaces" now list the corresponding items in
1321 ascending ID order, for consistency with all other "info" commands.
1323 * In Ada, the overloads selection menu has been enhanced to display the
1324 parameter types and the return types for the matching overloaded subprograms.
1328 maint set target-non-stop (on|off|auto)
1329 maint show target-non-stop
1330 Control whether GDB targets always operate in non-stop mode even if
1331 "set non-stop" is "off". The default is "auto", meaning non-stop
1332 mode is enabled if supported by the target.
1334 maint set bfd-sharing
1335 maint show bfd-sharing
1336 Control the reuse of bfd objects.
1339 show debug bfd-cache
1340 Control display of debugging info regarding bfd caching.
1344 Control display of debugging info regarding FreeBSD threads.
1346 set remote multiprocess-extensions-packet
1347 show remote multiprocess-extensions-packet
1348 Set/show the use of the remote protocol multiprocess extensions.
1350 set remote thread-events
1351 show remote thread-events
1352 Set/show the use of thread create/exit events.
1354 set ada print-signatures on|off
1355 show ada print-signatures"
1356 Control whether parameter types and return types are displayed in overloads
1357 selection menus. It is activaled (@code{on}) by default.
1361 Controls the maximum size of memory, in bytes, that GDB will
1362 allocate for value contents. Prevents incorrect programs from
1363 causing GDB to allocate overly large buffers. Default is 64k.
1365 * The "disassemble" command accepts a new modifier: /s.
1366 It prints mixed source+disassembly like /m with two differences:
1367 - disassembled instructions are now printed in program order, and
1368 - and source for all relevant files is now printed.
1369 The "/m" option is now considered deprecated: its "source-centric"
1370 output hasn't proved useful in practice.
1372 * The "record instruction-history" command accepts a new modifier: /s.
1373 It behaves exactly like /m and prints mixed source+disassembly.
1375 * The "set scheduler-locking" command supports a new mode "replay".
1376 It behaves like "off" in record mode and like "on" in replay mode.
1378 * Support for various ROM monitors has been removed:
1380 target dbug dBUG ROM monitor for Motorola ColdFire
1381 target picobug Motorola picobug monitor
1382 target dink32 DINK32 ROM monitor for PowerPC
1383 target m32r Renesas M32R/D ROM monitor
1384 target mon2000 mon2000 ROM monitor
1385 target ppcbug PPCBUG ROM monitor for PowerPC
1387 * Support for reading/writing memory and extracting values on architectures
1388 whose memory is addressable in units of any integral multiple of 8 bits.
1391 Allows to break when an Ada exception is handled.
1393 * New remote packets
1396 Indicates that an exec system call was executed.
1398 exec-events feature in qSupported
1399 The qSupported packet allows GDB to request support for exec
1400 events using the new 'gdbfeature' exec-event, and the qSupported
1401 response can contain the corresponding 'stubfeature'. Set and
1402 show commands can be used to display whether these features are enabled.
1405 Equivalent to interrupting with the ^C character, but works in
1408 thread created stop reason (T05 create:...)
1409 Indicates that the thread was just created and is stopped at entry.
1411 thread exit stop reply (w exitcode;tid)
1412 Indicates that the thread has terminated.
1415 Enables/disables thread create and exit event reporting. For
1416 example, this is used in non-stop mode when GDB stops a set of
1417 threads and synchronously waits for the their corresponding stop
1418 replies. Without exit events, if one of the threads exits, GDB
1419 would hang forever not knowing that it should no longer expect a
1420 stop for that same thread.
1423 Indicates that there are no resumed threads left in the target (all
1424 threads are stopped). The remote stub reports support for this stop
1425 reply to GDB's qSupported query.
1428 Enables/disables catching syscalls from the inferior process.
1429 The remote stub reports support for this packet to GDB's qSupported query.
1431 syscall_entry stop reason
1432 Indicates that a syscall was just called.
1434 syscall_return stop reason
1435 Indicates that a syscall just returned.
1437 * Extended-remote exec events
1439 ** GDB now has support for exec events on extended-remote Linux targets.
1440 For such targets with Linux kernels 2.5.46 and later, this enables
1441 follow-exec-mode and exec catchpoints.
1443 set remote exec-event-feature-packet
1444 show remote exec-event-feature-packet
1445 Set/show the use of the remote exec event feature.
1447 * Thread names in remote protocol
1449 The reply to qXfer:threads:read may now include a name attribute for each
1452 * Target remote mode fork and exec events
1454 ** GDB now has support for fork and exec events on target remote mode
1455 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1456 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1457 fork and exec catchpoints.
1459 * Remote syscall events
1461 ** GDB now has support for catch syscall on remote Linux targets,
1462 currently enabled on x86/x86_64 architectures.
1464 set remote catch-syscall-packet
1465 show remote catch-syscall-packet
1466 Set/show the use of the remote catch syscall feature.
1470 ** The -var-set-format command now accepts the zero-hexadecimal
1471 format. It outputs data in hexadecimal format with zero-padding on the
1476 ** gdb.InferiorThread objects have a new attribute "global_num",
1477 which refers to the thread's global thread ID. The existing
1478 "num" attribute now refers to the thread's per-inferior number.
1479 See "Per-inferior thread numbers" above.
1480 ** gdb.InferiorThread objects have a new attribute "inferior", which
1481 is the Inferior object the thread belongs to.
1483 *** Changes in GDB 7.10
1485 * Support for process record-replay and reverse debugging on aarch64*-linux*
1486 targets has been added. GDB now supports recording of A64 instruction set
1487 including advance SIMD instructions.
1489 * Support for Sun's version of the "stabs" debug file format has been removed.
1491 * GDB now honors the content of the file /proc/PID/coredump_filter
1492 (PID is the process ID) on GNU/Linux systems. This file can be used
1493 to specify the types of memory mappings that will be included in a
1494 corefile. For more information, please refer to the manual page of
1495 "core(5)". GDB also has a new command: "set use-coredump-filter
1496 on|off". It allows to set whether GDB will read the content of the
1497 /proc/PID/coredump_filter file when generating a corefile.
1499 * The "info os" command on GNU/Linux can now display information on
1501 "info os cpus" Listing of all cpus/cores on the system
1503 * GDB has two new commands: "set serial parity odd|even|none" and
1504 "show serial parity". These allows to set or show parity for the
1507 * The "info source" command now displays the producer string if it was
1508 present in the debug info. This typically includes the compiler version
1509 and may include things like its command line arguments.
1511 * The "info dll", an alias of the "info sharedlibrary" command,
1512 is now available on all platforms.
1514 * Directory names supplied to the "set sysroot" commands may be
1515 prefixed with "target:" to tell GDB to access shared libraries from
1516 the target system, be it local or remote. This replaces the prefix
1517 "remote:". The default sysroot has been changed from "" to
1518 "target:". "remote:" is automatically converted to "target:" for
1519 backward compatibility.
1521 * The system root specified by "set sysroot" will be prepended to the
1522 filename of the main executable (if reported to GDB as absolute by
1523 the operating system) when starting processes remotely, and when
1524 attaching to already-running local or remote processes.
1526 * GDB now supports automatic location and retrieval of executable
1527 files from remote targets. Remote debugging can now be initiated
1528 using only a "target remote" or "target extended-remote" command
1529 (no "set sysroot" or "file" commands are required). See "New remote
1532 * The "dump" command now supports verilog hex format.
1534 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1536 * On GNU/Linux, GDB and gdbserver are now able to access executable
1537 and shared library files without a "set sysroot" command when
1538 attaching to processes running in different mount namespaces from
1539 the debugger. This makes it possible to attach to processes in
1540 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1541 See "New remote packets" below.
1543 * The "tui reg" command now provides completion for all of the
1544 available register groups, including target specific groups.
1546 * The HISTSIZE environment variable is no longer read when determining
1547 the size of GDB's command history. GDB now instead reads the dedicated
1548 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1549 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1554 ** Memory ports can now be unbuffered.
1558 ** gdb.Objfile objects have a new attribute "username",
1559 which is the name of the objfile as specified by the user,
1560 without, for example, resolving symlinks.
1561 ** You can now write frame unwinders in Python.
1562 ** gdb.Type objects have a new method "optimized_out",
1563 returning optimized out gdb.Value instance of this type.
1564 ** gdb.Value objects have new methods "reference_value" and
1565 "const_value" which return a reference to the value and a
1566 "const" version of the value respectively.
1570 maint print symbol-cache
1571 Print the contents of the symbol cache.
1573 maint print symbol-cache-statistics
1574 Print statistics of symbol cache usage.
1576 maint flush-symbol-cache
1577 Flush the contents of the symbol cache.
1581 Start branch trace recording using Branch Trace Store (BTS) format.
1584 Evaluate expression by using the compiler and print result.
1588 Explicit commands for enabling and disabling tui mode.
1591 set mpx bound on i386 and amd64
1592 Support for bound table investigation on Intel MPX enabled applications.
1596 Start branch trace recording using Intel Processor Trace format.
1599 Print information about branch tracing internals.
1601 maint btrace packet-history
1602 Print the raw branch tracing data.
1604 maint btrace clear-packet-history
1605 Discard the stored raw branch tracing data.
1608 Discard all branch tracing data. It will be fetched and processed
1609 anew by the next "record" command.
1614 Renamed from "set debug dwarf2-die".
1615 show debug dwarf-die
1616 Renamed from "show debug dwarf2-die".
1618 set debug dwarf-read
1619 Renamed from "set debug dwarf2-read".
1620 show debug dwarf-read
1621 Renamed from "show debug dwarf2-read".
1623 maint set dwarf always-disassemble
1624 Renamed from "maint set dwarf2 always-disassemble".
1625 maint show dwarf always-disassemble
1626 Renamed from "maint show dwarf2 always-disassemble".
1628 maint set dwarf max-cache-age
1629 Renamed from "maint set dwarf2 max-cache-age".
1630 maint show dwarf max-cache-age
1631 Renamed from "maint show dwarf2 max-cache-age".
1633 set debug dwarf-line
1634 show debug dwarf-line
1635 Control display of debugging info regarding DWARF line processing.
1638 show max-completions
1639 Set the maximum number of candidates to be considered during
1640 completion. The default value is 200. This limit allows GDB
1641 to avoid generating large completion lists, the computation of
1642 which can cause the debugger to become temporarily unresponsive.
1644 set history remove-duplicates
1645 show history remove-duplicates
1646 Control the removal of duplicate history entries.
1648 maint set symbol-cache-size
1649 maint show symbol-cache-size
1650 Control the size of the symbol cache.
1652 set|show record btrace bts buffer-size
1653 Set and show the size of the ring buffer used for branch tracing in
1655 The obtained size may differ from the requested size. Use "info
1656 record" to see the obtained buffer size.
1658 set debug linux-namespaces
1659 show debug linux-namespaces
1660 Control display of debugging info regarding Linux namespaces.
1662 set|show record btrace pt buffer-size
1663 Set and show the size of the ring buffer used for branch tracing in
1664 Intel Processor Trace format.
1665 The obtained size may differ from the requested size. Use "info
1666 record" to see the obtained buffer size.
1668 maint set|show btrace pt skip-pad
1669 Set and show whether PAD packets are skipped when computing the
1672 * The command 'thread apply all' can now support new option '-ascending'
1673 to call its specified command for all threads in ascending order.
1675 * Python/Guile scripting
1677 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1678 special section named `.debug_gdb_scripts'.
1680 * New remote packets
1682 qXfer:btrace-conf:read
1683 Return the branch trace configuration for the current thread.
1685 Qbtrace-conf:bts:size
1686 Set the requested ring buffer size for branch tracing in BTS format.
1689 Enable Intel Procesor Trace-based branch tracing for the current
1690 process. The remote stub reports support for this packet to GDB's
1693 Qbtrace-conf:pt:size
1694 Set the requested ring buffer size for branch tracing in Intel Processor
1698 Indicates a memory breakpoint instruction was executed, irrespective
1699 of whether it was GDB that planted the breakpoint or the breakpoint
1700 is hardcoded in the program. This is required for correct non-stop
1704 Indicates the target stopped for a hardware breakpoint. This is
1705 required for correct non-stop mode operation.
1708 Return information about files on the remote system.
1710 qXfer:exec-file:read
1711 Return the full absolute name of the file that was executed to
1712 create a process running on the remote system.
1715 Select the filesystem on which vFile: operations with filename
1716 arguments will operate. This is required for GDB to be able to
1717 access files on remote targets where the remote stub does not
1718 share a common filesystem with the inferior(s).
1721 Indicates that a fork system call was executed.
1724 Indicates that a vfork system call was executed.
1726 vforkdone stop reason
1727 Indicates that a vfork child of the specified process has executed
1728 an exec or exit, allowing the vfork parent to resume execution.
1730 fork-events and vfork-events features in qSupported
1731 The qSupported packet allows GDB to request support for fork and
1732 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1733 and the qSupported response can contain the corresponding
1734 'stubfeatures'. Set and show commands can be used to display
1735 whether these features are enabled.
1737 * Extended-remote fork events
1739 ** GDB now has support for fork events on extended-remote Linux
1740 targets. For targets with Linux kernels 2.5.60 and later, this
1741 enables follow-fork-mode and detach-on-fork for both fork and
1742 vfork, as well as fork and vfork catchpoints.
1744 * The info record command now shows the recording format and the
1745 branch tracing configuration for the current thread when using
1746 the btrace record target.
1747 For the BTS format, it shows the ring buffer size.
1749 * GDB now has support for DTrace USDT (Userland Static Defined
1750 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1752 * GDB now supports access to vector registers on S/390 GNU/Linux
1755 * Removed command line options
1757 -xdb HP-UX XDB compatibility mode.
1759 * Removed targets and native configurations
1761 HP/PA running HP-UX hppa*-*-hpux*
1762 Itanium running HP-UX ia64-*-hpux*
1764 * New configure options
1767 This configure option allows the user to build GDB with support for
1768 Intel Processor Trace (default: auto). This requires libipt.
1770 --with-libipt-prefix=PATH
1771 Specify the path to the version of libipt that GDB should use.
1772 $PATH/include should contain the intel-pt.h header and
1773 $PATH/lib should contain the libipt.so library.
1775 *** Changes in GDB 7.9.1
1779 ** Xmethods can now specify a result type.
1781 *** Changes in GDB 7.9
1783 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1787 ** You can now access frame registers from Python scripts.
1788 ** New attribute 'producer' for gdb.Symtab objects.
1789 ** gdb.Objfile objects have a new attribute "progspace",
1790 which is the gdb.Progspace object of the containing program space.
1791 ** gdb.Objfile objects have a new attribute "owner".
1792 ** gdb.Objfile objects have a new attribute "build_id",
1793 which is the build ID generated when the file was built.
1794 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1795 ** A new event "gdb.clear_objfiles" has been added, triggered when
1796 selecting a new file to debug.
1797 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1798 ** New function gdb.lookup_objfile.
1800 New events which are triggered when GDB modifies the state of the
1803 ** gdb.events.inferior_call_pre: Function call is about to be made.
1804 ** gdb.events.inferior_call_post: Function call has just been made.
1805 ** gdb.events.memory_changed: A memory location has been altered.
1806 ** gdb.events.register_changed: A register has been altered.
1808 * New Python-based convenience functions:
1810 ** $_caller_is(name [, number_of_frames])
1811 ** $_caller_matches(regexp [, number_of_frames])
1812 ** $_any_caller_is(name [, number_of_frames])
1813 ** $_any_caller_matches(regexp [, number_of_frames])
1815 * GDB now supports the compilation and injection of source code into
1816 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1817 to compile the source code to object code, and if successful, inject
1818 and execute that code within the current context of the inferior.
1819 Currently the C language is supported. The commands used to
1820 interface with this new feature are:
1822 compile code [-raw|-r] [--] [source code]
1823 compile file [-raw|-r] filename
1827 demangle [-l language] [--] name
1828 Demangle "name" in the specified language, or the current language
1829 if elided. This command is renamed from the "maint demangle" command.
1830 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1831 as "maint demangler-warning".
1833 queue-signal signal-name-or-number
1834 Queue a signal to be delivered to the thread when it is resumed.
1836 add-auto-load-scripts-directory directory
1837 Add entries to the list of directories from which to load auto-loaded
1840 maint print user-registers
1841 List all currently available "user" registers.
1843 compile code [-r|-raw] [--] [source code]
1844 Compile, inject, and execute in the inferior the executable object
1845 code produced by compiling the provided source code.
1847 compile file [-r|-raw] filename
1848 Compile and inject into the inferior the executable object code
1849 produced by compiling the source code stored in the filename
1852 * On resume, GDB now always passes the signal the program had stopped
1853 for to the thread the signal was sent to, even if the user changed
1854 threads before resuming. Previously GDB would often (but not
1855 always) deliver the signal to the thread that happens to be current
1858 * Conversely, the "signal" command now consistently delivers the
1859 requested signal to the current thread. GDB now asks for
1860 confirmation if the program had stopped for a signal and the user
1861 switched threads meanwhile.
1863 * "breakpoint always-inserted" modes "off" and "auto" merged.
1865 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1866 won't remove breakpoints from the target until all threads stop,
1867 even in non-stop mode. The "auto" mode has been removed, and "off"
1868 is now the default mode.
1872 set debug symbol-lookup
1873 show debug symbol-lookup
1874 Control display of debugging info regarding symbol lookup.
1878 ** The -list-thread-groups command outputs an exit-code field for
1879 inferiors that have exited.
1883 MIPS SDE mips*-sde*-elf*
1887 Support for these obsolete configurations has been removed.
1889 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1890 SGI Irix-5.x mips-*-irix5*
1891 SGI Irix-6.x mips-*-irix6*
1892 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1893 VAX running Ultrix vax-*-ultrix*
1895 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1896 and "assf"), have been removed. Use the "sharedlibrary" command, or
1897 its alias "share", instead.
1899 *** Changes in GDB 7.8
1901 * New command line options
1904 This is an alias for the --data-directory option.
1906 * GDB supports printing and modifying of variable length automatic arrays
1907 as specified in ISO C99.
1909 * The ARM simulator now supports instruction level tracing
1910 with or without disassembly.
1914 GDB now has support for scripting using Guile. Whether this is
1915 available is determined at configure time.
1916 Guile version 2.0 or greater is required.
1917 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1919 * New commands (for set/show, see "New options" below)
1923 Invoke CODE by passing it to the Guile interpreter.
1927 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1929 info auto-load guile-scripts [regexp]
1930 Print the list of automatically loaded Guile scripts.
1932 * The source command is now capable of sourcing Guile scripts.
1933 This feature is dependent on the debugger being built with Guile support.
1937 set print symbol-loading (off|brief|full)
1938 show print symbol-loading
1939 Control whether to print informational messages when loading symbol
1940 information for a file. The default is "full", but when debugging
1941 programs with large numbers of shared libraries the amount of output
1942 becomes less useful.
1944 set guile print-stack (none|message|full)
1945 show guile print-stack
1946 Show a stack trace when an error is encountered in a Guile script.
1948 set auto-load guile-scripts (on|off)
1949 show auto-load guile-scripts
1950 Control auto-loading of Guile script files.
1952 maint ada set ignore-descriptive-types (on|off)
1953 maint ada show ignore-descriptive-types
1954 Control whether the debugger should ignore descriptive types in Ada
1955 programs. The default is not to ignore the descriptive types. See
1956 the user manual for more details on descriptive types and the intended
1957 usage of this option.
1959 set auto-connect-native-target
1961 Control whether GDB is allowed to automatically connect to the
1962 native target for the run, attach, etc. commands when not connected
1963 to any target yet. See also "target native" below.
1965 set record btrace replay-memory-access (read-only|read-write)
1966 show record btrace replay-memory-access
1967 Control what memory accesses are allowed during replay.
1969 maint set target-async (on|off)
1970 maint show target-async
1971 This controls whether GDB targets operate in synchronous or
1972 asynchronous mode. Normally the default is asynchronous, if it is
1973 available; but this can be changed to more easily debug problems
1974 occurring only in synchronous mode.
1976 set mi-async (on|off)
1978 Control whether MI asynchronous mode is preferred. This supersedes
1979 "set target-async" of previous GDB versions.
1981 * "set target-async" is deprecated as a CLI option and is now an alias
1982 for "set mi-async" (only puts MI into async mode).
1984 * Background execution commands (e.g., "c&", "s&", etc.) are now
1985 possible ``out of the box'' if the target supports them. Previously
1986 the user would need to explicitly enable the possibility with the
1987 "set target-async on" command.
1989 * New features in the GDB remote stub, GDBserver
1991 ** New option --debug-format=option1[,option2,...] allows one to add
1992 additional text to each output. At present only timestamps
1993 are supported: --debug-format=timestamps.
1994 Timestamps can also be turned on with the
1995 "monitor set debug-format timestamps" command from GDB.
1997 * The 'record instruction-history' command now starts counting instructions
1998 at one. This also affects the instruction ranges reported by the
1999 'record function-call-history' command when given the /i modifier.
2001 * The command 'record function-call-history' supports a new modifier '/c' to
2002 indent the function names based on their call stack depth.
2003 The fields for the '/i' and '/l' modifier have been reordered.
2004 The source line range is now prefixed with 'at'.
2005 The instruction range is now prefixed with 'inst'.
2006 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
2007 "record instruction-history" and "list" commands.
2009 * The ranges given as arguments to the 'record function-call-history' and
2010 'record instruction-history' commands are now inclusive.
2012 * The btrace record target now supports the 'record goto' command.
2013 For locations inside the execution trace, the back trace is computed
2014 based on the information stored in the execution trace.
2016 * The btrace record target supports limited reverse execution and replay.
2017 The target does not record data and therefore does not allow reading
2018 memory or registers.
2020 * The "catch syscall" command now works on s390*-linux* targets.
2022 * The "compare-sections" command is no longer specific to target
2023 remote. It now works with all targets.
2025 * All native targets are now consistently called "native".
2026 Consequently, the "target child", "target GNU", "target djgpp",
2027 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
2028 commands have been replaced with "target native". The QNX/NTO port
2029 leaves the "procfs" target in place and adds a "native" target for
2030 consistency with other ports. The impact on users should be minimal
2031 as these commands previously either throwed an error, or were
2032 no-ops. The target's name is visible in the output of the following
2033 commands: "help target", "info target", "info files", "maint print
2036 * The "target native" command now connects to the native target. This
2037 can be used to launch native programs even when "set
2038 auto-connect-native-target" is set to off.
2040 * GDB now supports access to Intel MPX registers on GNU/Linux.
2042 * Support for Intel AVX-512 registers on GNU/Linux.
2043 Support displaying and modifying Intel AVX-512 registers
2044 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
2046 * New remote packets
2048 qXfer:btrace:read's annex
2049 The qXfer:btrace:read packet supports a new annex 'delta' to read
2050 branch trace incrementally.
2054 ** Valid Python operations on gdb.Value objects representing
2055 structs/classes invoke the corresponding overloaded operators if
2057 ** New `Xmethods' feature in the Python API. Xmethods are
2058 additional methods or replacements for existing methods of a C++
2059 class. This feature is useful for those cases where a method
2060 defined in C++ source code could be inlined or optimized out by
2061 the compiler, making it unavailable to GDB.
2064 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
2066 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
2067 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
2068 its alias "share", instead.
2070 * The commands "set remotebaud" and "show remotebaud" are no longer
2071 supported. Use "set serial baud" and "show serial baud" (respectively)
2076 ** A new option "-gdb-set mi-async" replaces "-gdb-set
2077 target-async". The latter is left as a deprecated alias of the
2078 former for backward compatibility. If the target supports it,
2079 CLI background execution commands are now always possible by
2080 default, independently of whether the frontend stated a
2081 preference for asynchronous execution with "-gdb-set mi-async".
2082 Previously "-gdb-set target-async off" affected both MI execution
2083 commands and CLI execution commands.
2085 *** Changes in GDB 7.7
2087 * Improved support for process record-replay and reverse debugging on
2088 arm*-linux* targets. Support for thumb32 and syscall instruction
2089 recording has been added.
2091 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
2093 * GDB now supports Fission DWP file format version 2.
2094 http://gcc.gnu.org/wiki/DebugFission
2096 * New convenience function "$_isvoid", to check whether an expression
2097 is void. A void expression is an expression where the type of the
2098 result is "void". For example, some convenience variables may be
2099 "void" when evaluated (e.g., "$_exitcode" before the execution of
2100 the program being debugged; or an undefined convenience variable).
2101 Another example, when calling a function whose return type is
2104 * The "maintenance print objfiles" command now takes an optional regexp.
2106 * The "catch syscall" command now works on arm*-linux* targets.
2108 * GDB now consistently shows "<not saved>" when printing values of
2109 registers the debug info indicates have not been saved in the frame
2110 and there's nowhere to retrieve them from
2111 (callee-saved/call-clobbered registers):
2116 (gdb) info registers rax
2119 Before, the former would print "<optimized out>", and the latter
2120 "*value not available*".
2122 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
2127 ** Frame filters and frame decorators have been added.
2128 ** Temporary breakpoints are now supported.
2129 ** Line tables representation has been added.
2130 ** New attribute 'parent_type' for gdb.Field objects.
2131 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
2132 ** New attribute 'name' for gdb.Type objects.
2136 Nios II ELF nios2*-*-elf
2137 Nios II GNU/Linux nios2*-*-linux
2138 Texas Instruments MSP430 msp430*-*-elf
2140 * Removed native configurations
2142 Support for these a.out NetBSD and OpenBSD obsolete configurations has
2143 been removed. ELF variants of these configurations are kept supported.
2145 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
2146 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
2147 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
2148 i[34567]86-*-openbsd3.[0-3]
2149 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
2150 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
2151 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
2155 Like "catch throw", but catches a re-thrown exception.
2156 maint check-psymtabs
2157 Renamed from old "maint check-symtabs".
2159 Perform consistency checks on symtabs.
2160 maint expand-symtabs
2161 Expand symtabs matching an optional regexp.
2164 Display the details of GDB configure-time options.
2166 maint set|show per-command
2167 maint set|show per-command space
2168 maint set|show per-command time
2169 maint set|show per-command symtab
2170 Enable display of per-command gdb resource usage.
2172 remove-symbol-file FILENAME
2173 remove-symbol-file -a ADDRESS
2174 Remove a symbol file added via add-symbol-file. The file to remove
2175 can be identified by its filename or by an address that lies within
2176 the boundaries of this symbol file in memory.
2179 info exceptions REGEXP
2180 Display the list of Ada exceptions defined in the program being
2181 debugged. If provided, only the exceptions whose names match REGEXP
2186 set debug symfile off|on
2188 Control display of debugging info regarding reading symbol files and
2189 symbol tables within those files
2191 set print raw frame-arguments
2192 show print raw frame-arguments
2193 Set/show whether to print frame arguments in raw mode,
2194 disregarding any defined pretty-printers.
2196 set remote trace-status-packet
2197 show remote trace-status-packet
2198 Set/show the use of remote protocol qTStatus packet.
2202 Control display of debugging messages related to Nios II targets.
2206 Control whether target-assisted range stepping is enabled.
2208 set startup-with-shell
2209 show startup-with-shell
2210 Specifies whether Unix child processes are started via a shell or
2215 Use the target memory cache for accesses to the code segment. This
2216 improves performance of remote debugging (particularly disassembly).
2218 * You can now use a literal value 'unlimited' for options that
2219 interpret 0 or -1 as meaning "unlimited". E.g., "set
2220 trace-buffer-size unlimited" is now an alias for "set
2221 trace-buffer-size -1" and "set height unlimited" is now an alias for
2224 * The "set debug symtab-create" debugging option of GDB has been changed to
2225 accept a verbosity level. 0 means "off", 1 provides basic debugging
2226 output, and values of 2 or greater provides more verbose output.
2228 * New command-line options
2230 Display the details of GDB configure-time options.
2232 * The command 'tsave' can now support new option '-ctf' to save trace
2233 buffer in Common Trace Format.
2235 * Newly installed $prefix/bin/gcore acts as a shell interface for the
2238 * GDB now implements the the C++ 'typeid' operator.
2240 * The new convenience variable $_exception holds the exception being
2241 thrown or caught at an exception-related catchpoint.
2243 * The exception-related catchpoints, like "catch throw", now accept a
2244 regular expression which can be used to filter exceptions by type.
2246 * The new convenience variable $_exitsignal is automatically set to
2247 the terminating signal number when the program being debugged dies
2248 due to an uncaught signal.
2252 ** All MI commands now accept an optional "--language" option.
2253 Support for this feature can be verified by using the "-list-features"
2254 command, which should contain "language-option".
2256 ** The new command -info-gdb-mi-command allows the user to determine
2257 whether a GDB/MI command is supported or not.
2259 ** The "^error" result record returned when trying to execute an undefined
2260 GDB/MI command now provides a variable named "code" whose content is the
2261 "undefined-command" error code. Support for this feature can be verified
2262 by using the "-list-features" command, which should contain
2263 "undefined-command-error-code".
2265 ** The -trace-save MI command can optionally save trace buffer in Common
2268 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2270 ** The command -data-list-register-values now accepts an optional
2271 "--skip-unavailable" option. When used, only the available registers
2274 ** The new command -trace-frame-collected dumps collected variables,
2275 computed expressions, tvars, memory and registers in a traceframe.
2277 ** The commands -stack-list-locals, -stack-list-arguments and
2278 -stack-list-variables now accept an option "--skip-unavailable".
2279 When used, only the available locals or arguments are displayed.
2281 ** The -exec-run command now accepts an optional "--start" option.
2282 When used, the command follows the same semantics as the "start"
2283 command, stopping the program's execution at the start of its
2284 main subprogram. Support for this feature can be verified using
2285 the "-list-features" command, which should contain
2286 "exec-run-start-option".
2288 ** The new commands -catch-assert and -catch-exceptions insert
2289 catchpoints stopping the program when Ada exceptions are raised.
2291 ** The new command -info-ada-exceptions provides the equivalent of
2292 the new "info exceptions" command.
2294 * New system-wide configuration scripts
2295 A GDB installation now provides scripts suitable for use as system-wide
2296 configuration scripts for the following systems:
2300 * GDB now supports target-assigned range stepping with remote targets.
2301 This improves the performance of stepping source lines by reducing
2302 the number of control packets from/to GDB. See "New remote packets"
2305 * GDB now understands the element 'tvar' in the XML traceframe info.
2306 It has the id of the collected trace state variables.
2308 * On S/390 targets that provide the transactional-execution feature,
2309 the program interruption transaction diagnostic block (TDB) is now
2310 represented as a number of additional "registers" in GDB.
2312 * New remote packets
2316 The vCont packet supports a new 'r' action, that tells the remote
2317 stub to step through an address range itself, without GDB
2318 involvemement at each single-step.
2320 qXfer:libraries-svr4:read's annex
2321 The previously unused annex of the qXfer:libraries-svr4:read packet
2322 is now used to support passing an argument list. The remote stub
2323 reports support for this argument list to GDB's qSupported query.
2324 The defined arguments are "start" and "prev", used to reduce work
2325 necessary for library list updating, resulting in significant
2328 * New features in the GDB remote stub, GDBserver
2330 ** GDBserver now supports target-assisted range stepping. Currently
2331 enabled on x86/x86_64 GNU/Linux targets.
2333 ** GDBserver now adds element 'tvar' in the XML in the reply to
2334 'qXfer:traceframe-info:read'. It has the id of the collected
2335 trace state variables.
2337 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2340 * New 'z' formatter for printing and examining memory, this displays the
2341 value as hexadecimal zero padded on the left to the size of the type.
2343 * GDB can now use Windows x64 unwinding data.
2345 * The "set remotebaud" command has been replaced by "set serial baud".
2346 Similarly, "show remotebaud" has been replaced by "show serial baud".
2347 The "set remotebaud" and "show remotebaud" commands are still available
2348 to provide backward compatibility with older versions of GDB.
2350 *** Changes in GDB 7.6
2352 * Target record has been renamed to record-full.
2353 Record/replay is now enabled with the "record full" command.
2354 This also affects settings that are associated with full record/replay
2355 that have been moved from "set/show record" to "set/show record full":
2357 set|show record full insn-number-max
2358 set|show record full stop-at-limit
2359 set|show record full memory-query
2361 * A new record target "record-btrace" has been added. The new target
2362 uses hardware support to record the control-flow of a process. It
2363 does not support replaying the execution, but it implements the
2364 below new commands for investigating the recorded execution log.
2365 This new recording method can be enabled using:
2369 The "record-btrace" target is only available on Intel Atom processors
2370 and requires a Linux kernel 2.6.32 or later.
2372 * Two new commands have been added for record/replay to give information
2373 about the recorded execution without having to replay the execution.
2374 The commands are only supported by "record btrace".
2376 record instruction-history prints the execution history at
2377 instruction granularity
2379 record function-call-history prints the execution history at
2380 function granularity
2382 * New native configurations
2384 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2385 FreeBSD/powerpc powerpc*-*-freebsd
2386 x86_64/Cygwin x86_64-*-cygwin*
2387 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2391 ARM AArch64 aarch64*-*-elf
2392 ARM AArch64 GNU/Linux aarch64*-*-linux
2393 Lynx 178 PowerPC powerpc-*-lynx*178
2394 x86_64/Cygwin x86_64-*-cygwin*
2395 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2397 * If the configured location of system.gdbinit file (as given by the
2398 --with-system-gdbinit option at configure time) is in the
2399 data-directory (as specified by --with-gdb-datadir at configure
2400 time) or in one of its subdirectories, then GDB will look for the
2401 system-wide init file in the directory specified by the
2402 --data-directory command-line option.
2404 * New command line options:
2406 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2407 other initialization files, unlike -nx which disables all of them.
2409 * Removed command line options
2411 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2414 * The 'ptype' and 'whatis' commands now accept an argument to control
2417 * 'info proc' now works on some core files.
2421 ** Vectors can be created with gdb.Type.vector.
2423 ** Python's atexit.register now works in GDB.
2425 ** Types can be pretty-printed via a Python API.
2427 ** Python 3 is now supported (in addition to Python 2.4 or later)
2429 ** New class gdb.Architecture exposes GDB's internal representation
2430 of architecture in the Python API.
2432 ** New method Frame.architecture returns the gdb.Architecture object
2433 corresponding to the frame's architecture.
2435 * New Python-based convenience functions:
2437 ** $_memeq(buf1, buf2, length)
2438 ** $_streq(str1, str2)
2440 ** $_regex(str, regex)
2442 * The 'cd' command now defaults to using '~' (the home directory) if not
2445 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2446 default for GCC since November 2000.
2448 * The command 'forward-search' can now be abbreviated as 'fo'.
2450 * The command 'info tracepoints' can now display 'installed on target'
2451 or 'not installed on target' for each non-pending location of tracepoint.
2453 * New configure options
2455 --enable-libmcheck/--disable-libmcheck
2456 By default, development versions are built with -lmcheck on hosts
2457 that support it, in order to help track memory corruption issues.
2458 Release versions, on the other hand, are built without -lmcheck
2459 by default. The --enable-libmcheck/--disable-libmcheck configure
2460 options allow the user to override that default.
2461 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2462 This configure option allows the user to build GDB with
2463 libbabeltrace using which GDB can read Common Trace Format data.
2465 * New commands (for set/show, see "New options" below)
2468 Catch signals. This is similar to "handle", but allows commands and
2469 conditions to be attached.
2472 List the BFDs known to GDB.
2474 python-interactive [command]
2476 Start a Python interactive prompt, or evaluate the optional command
2477 and print the result of expressions.
2480 "py" is a new alias for "python".
2482 enable type-printer [name]...
2483 disable type-printer [name]...
2484 Enable or disable type printers.
2488 ** For the Renesas Super-H architecture, the "regs" command has been removed
2489 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2494 set print type methods (on|off)
2495 show print type methods
2496 Control whether method declarations are displayed by "ptype".
2497 The default is to show them.
2499 set print type typedefs (on|off)
2500 show print type typedefs
2501 Control whether typedef definitions are displayed by "ptype".
2502 The default is to show them.
2504 set filename-display basename|relative|absolute
2505 show filename-display
2506 Control the way in which filenames is displayed.
2507 The default is "relative", which preserves previous behavior.
2509 set trace-buffer-size
2510 show trace-buffer-size
2511 Request target to change the size of trace buffer.
2513 set remote trace-buffer-size-packet auto|on|off
2514 show remote trace-buffer-size-packet
2515 Control the use of the remote protocol `QTBuffer:size' packet.
2519 Control display of debugging messages related to ARM AArch64.
2522 set debug coff-pe-read
2523 show debug coff-pe-read
2524 Control display of debugging messages related to reading of COFF/PE
2529 Control display of debugging messages related to Mach-O symbols
2532 set debug notification
2533 show debug notification
2534 Control display of debugging info for async remote notification.
2538 ** Command parameter changes are now notified using new async record
2539 "=cmd-param-changed".
2540 ** Trace frame changes caused by command "tfind" are now notified using
2541 new async record "=traceframe-changed".
2542 ** The creation, deletion and modification of trace state variables
2543 are now notified using new async records "=tsv-created",
2544 "=tsv-deleted" and "=tsv-modified".
2545 ** The start and stop of process record are now notified using new
2546 async record "=record-started" and "=record-stopped".
2547 ** Memory changes are now notified using new async record
2549 ** The data-disassemble command response will include a "fullname" field
2550 containing the absolute file name when source has been requested.
2551 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2552 command, to allow pattern filling of memory areas.
2553 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2554 library load/unload events.
2555 ** The response to breakpoint commands and breakpoint async records
2556 includes an "installed" field containing a boolean state about each
2557 non-pending tracepoint location is whether installed on target or not.
2558 ** Output of the "-trace-status" command includes a "trace-file" field
2559 containing the name of the trace file being examined. This field is
2560 optional, and only present when examining a trace file.
2561 ** The "fullname" field is now always present along with the "file" field,
2562 even if the file cannot be found by GDB.
2564 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2565 You must have the LZMA library available when configuring GDB for this
2566 feature to be enabled. For more information, see:
2567 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2569 * New remote packets
2572 Set the size of trace buffer. The remote stub reports support for this
2573 packet to gdb's qSupported query.
2576 Enable Branch Trace Store (BTS)-based branch tracing for the current
2577 thread. The remote stub reports support for this packet to gdb's
2581 Disable branch tracing for the current thread. The remote stub reports
2582 support for this packet to gdb's qSupported query.
2585 Read the traced branches for the current thread. The remote stub
2586 reports support for this packet to gdb's qSupported query.
2588 *** Changes in GDB 7.5
2590 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2591 for more x32 ABI info.
2593 * GDB now supports access to MIPS DSP registers on Linux targets.
2595 * GDB now supports debugging microMIPS binaries.
2597 * The "info os" command on GNU/Linux can now display information on
2598 several new classes of objects managed by the operating system:
2599 "info os procgroups" lists process groups
2600 "info os files" lists file descriptors
2601 "info os sockets" lists internet-domain sockets
2602 "info os shm" lists shared-memory regions
2603 "info os semaphores" lists semaphores
2604 "info os msg" lists message queues
2605 "info os modules" lists loaded kernel modules
2607 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2608 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2609 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2610 options and inspect the probe arguments using the new $_probe_arg family
2611 of convenience variables. You can obtain more information about SystemTap
2612 in <http://sourceware.org/systemtap/>.
2614 * GDB now supports reversible debugging on ARM, it allows you to
2615 debug basic ARM and THUMB instructions, and provides
2616 record/replay support.
2618 * The option "symbol-reloading" has been deleted as it is no longer used.
2622 ** GDB commands implemented in Python can now be put in command class
2625 ** The "maint set python print-stack on|off" is now deleted.
2627 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2628 apply "flag enum"-style pretty-printing to any enum.
2630 ** gdb.lookup_symbol can now work when there is no current frame.
2632 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2633 the source at which the symbol was defined.
2635 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2636 method 'value'. The former indicates whether the symbol needs a
2637 frame in order to compute its value, and the latter computes the
2640 ** A new method 'referenced_value' on gdb.Value objects which can
2641 dereference pointer as well as C++ reference values.
2643 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2644 which return the global and static blocks (as gdb.Block objects),
2645 of the underlying symbol table, respectively.
2647 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2648 object associated with a PC value.
2650 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2651 of the address range occupied by code for the current source line.
2653 * Go language support.
2654 GDB now supports debugging programs written in the Go programming
2657 * GDBserver now supports stdio connections.
2658 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2660 * The binary "gdbtui" can no longer be built or installed.
2661 Use "gdb -tui" instead.
2663 * GDB will now print "flag" enums specially. A flag enum is one where
2664 all the enumerator values have no bits in common when pairwise
2665 "and"ed. When printing a value whose type is a flag enum, GDB will
2666 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2667 (gdb) print (enum E) 3
2670 * The filename part of a linespec will now match trailing components
2671 of a source file name. For example, "break gcc/expr.c:1000" will
2672 now set a breakpoint in build/gcc/expr.c, but not
2673 build/libcpp/expr.c.
2675 * The "info proc" and "generate-core-file" commands will now also
2676 work on remote targets connected to GDBserver on Linux.
2678 * The command "info catch" has been removed. It has been disabled
2679 since December 2007.
2681 * The "catch exception" and "catch assert" commands now accept
2682 a condition at the end of the command, much like the "break"
2683 command does. For instance:
2685 (gdb) catch exception Constraint_Error if Barrier = True
2687 Previously, it was possible to add a condition to such catchpoints,
2688 but it had to be done as a second step, after the catchpoint had been
2689 created, using the "condition" command.
2691 * The "info static-tracepoint-marker" command will now also work on
2692 native Linux targets with in-process agent.
2694 * GDB can now set breakpoints on inlined functions.
2696 * The .gdb_index section has been updated to include symbols for
2697 inlined functions. GDB will ignore older .gdb_index sections by
2698 default, which could cause symbol files to be loaded more slowly
2699 until their .gdb_index sections can be recreated. The new command
2700 "set use-deprecated-index-sections on" will cause GDB to use any older
2701 .gdb_index sections it finds. This will restore performance, but the
2702 ability to set breakpoints on inlined functions will be lost in symbol
2703 files with older .gdb_index sections.
2705 The .gdb_index section has also been updated to record more information
2706 about each symbol. This speeds up the "info variables", "info functions"
2707 and "info types" commands when used with programs having the .gdb_index
2708 section, as well as speeding up debugging with shared libraries using
2709 the .gdb_index section.
2711 * Ada support for GDB/MI Variable Objects has been added.
2713 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2718 ** New command -info-os is the MI equivalent of "info os".
2720 ** Output logs ("set logging" and related) now include MI output.
2724 ** "set use-deprecated-index-sections on|off"
2725 "show use-deprecated-index-sections on|off"
2726 Controls the use of deprecated .gdb_index sections.
2728 ** "catch load" and "catch unload" can be used to stop when a shared
2729 library is loaded or unloaded, respectively.
2731 ** "enable count" can be used to auto-disable a breakpoint after
2734 ** "info vtbl" can be used to show the virtual method tables for
2735 C++ and Java objects.
2737 ** "explore" and its sub commands "explore value" and "explore type"
2738 can be used to recursively explore values and types of
2739 expressions. These commands are available only if GDB is
2740 configured with '--with-python'.
2742 ** "info auto-load" shows status of all kinds of auto-loaded files,
2743 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2744 sequences of commands files, "info auto-load python-scripts"
2745 shows status of auto-loading Python script files,
2746 "info auto-load local-gdbinit" shows status of loading init file
2747 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2748 status of inferior specific thread debugging shared library loading.
2750 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2751 and "show auto-load-scripts" commands have been deprecated, use their
2752 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2753 and "show auto-load python-scripts" counterparts instead.
2755 ** "dprintf location,format,args..." creates a dynamic printf, which
2756 is basically a breakpoint that does a printf and immediately
2757 resumes your program's execution, so it is like a printf that you
2758 can insert dynamically at runtime instead of at compiletime.
2760 ** "set print symbol"
2762 Controls whether GDB attempts to display the symbol, if any,
2763 corresponding to addresses it prints. This defaults to "on", but
2764 you can set it to "off" to restore GDB's previous behavior.
2766 * Deprecated commands
2768 ** For the Renesas Super-H architecture, the "regs" command has been
2769 deprecated, and "info all-registers" should be used instead.
2773 Renesas RL78 rl78-*-elf
2774 HP OpenVMS ia64 ia64-hp-openvms*
2776 * GDBserver supports evaluation of breakpoint conditions. When
2777 support is advertised by GDBserver, GDB may be told to send the
2778 breakpoint conditions in bytecode form to GDBserver. GDBserver
2779 will only report the breakpoint trigger to GDB when its condition
2784 set mips compression
2785 show mips compression
2786 Select the compressed ISA encoding used in functions that have no symbol
2787 information available. The encoding can be set to either of:
2790 and is updated automatically from ELF file flags if available.
2792 set breakpoint condition-evaluation
2793 show breakpoint condition-evaluation
2794 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2795 GDBserver ("target"). Default option "auto" chooses the most efficient
2797 This option can improve debugger efficiency depending on the speed of the
2801 Disable auto-loading globally.
2804 Show auto-loading setting of all kinds of auto-loaded files.
2806 set auto-load gdb-scripts on|off
2807 show auto-load gdb-scripts
2808 Control auto-loading of GDB canned sequences of commands files.
2810 set auto-load python-scripts on|off
2811 show auto-load python-scripts
2812 Control auto-loading of Python script files.
2814 set auto-load local-gdbinit on|off
2815 show auto-load local-gdbinit
2816 Control loading of init file (.gdbinit) from current directory.
2818 set auto-load libthread-db on|off
2819 show auto-load libthread-db
2820 Control auto-loading of inferior specific thread debugging shared library.
2822 set auto-load scripts-directory <dir1>[:<dir2>...]
2823 show auto-load scripts-directory
2824 Set a list of directories from which to load auto-loaded scripts.
2825 Automatically loaded Python scripts and GDB scripts are located in one
2826 of the directories listed by this option.
2827 The delimiter (':' above) may differ according to the host platform.
2829 set auto-load safe-path <dir1>[:<dir2>...]
2830 show auto-load safe-path
2831 Set a list of directories from which it is safe to auto-load files.
2832 The delimiter (':' above) may differ according to the host platform.
2834 set debug auto-load on|off
2835 show debug auto-load
2836 Control display of debugging info for auto-loading the files above.
2838 set dprintf-style gdb|call|agent
2840 Control the way in which a dynamic printf is performed; "gdb"
2841 requests a GDB printf command, while "call" causes dprintf to call a
2842 function in the inferior. "agent" requests that the target agent
2843 (such as GDBserver) do the printing.
2845 set dprintf-function <expr>
2846 show dprintf-function
2847 set dprintf-channel <expr>
2848 show dprintf-channel
2849 Set the function and optional first argument to the call when using
2850 the "call" style of dynamic printf.
2852 set disconnected-dprintf on|off
2853 show disconnected-dprintf
2854 Control whether agent-style dynamic printfs continue to be in effect
2855 after GDB disconnects.
2857 * New configure options
2859 --with-auto-load-dir
2860 Configure default value for the 'set auto-load scripts-directory'
2861 setting above. It defaults to '$debugdir:$datadir/auto-load',
2862 $debugdir representing global debugging info directories (available
2863 via 'show debug-file-directory') and $datadir representing GDB's data
2864 directory (available via 'show data-directory').
2866 --with-auto-load-safe-path
2867 Configure default value for the 'set auto-load safe-path' setting
2868 above. It defaults to the --with-auto-load-dir setting.
2870 --without-auto-load-safe-path
2871 Set 'set auto-load safe-path' to '/', effectively disabling this
2874 * New remote packets
2876 z0/z1 conditional breakpoints extension
2878 The z0/z1 breakpoint insertion packets have been extended to carry
2879 a list of conditional expressions over to the remote stub depending on the
2880 condition evaluation mode. The use of this extension can be controlled
2881 via the "set remote conditional-breakpoints-packet" command.
2885 Specify the signals which the remote stub may pass to the debugged
2886 program without GDB involvement.
2888 * New command line options
2890 --init-command=FILE, -ix Like --command, -x but execute it
2891 before loading inferior.
2892 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2893 execute it before loading inferior.
2895 *** Changes in GDB 7.4
2897 * GDB now handles ambiguous linespecs more consistently; the existing
2898 FILE:LINE support has been expanded to other types of linespecs. A
2899 breakpoint will now be set on all matching locations in all
2900 inferiors, and locations will be added or removed according to
2903 * GDB now allows you to skip uninteresting functions and files when
2904 stepping with the "skip function" and "skip file" commands.
2906 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2907 and "show remote hardware-watchpoint-length-limit". These allows to
2908 set or show the maximum length limit (in bytes) of a remote
2909 target hardware watchpoint.
2911 This allows e.g. to use "unlimited" hardware watchpoints with the
2912 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2913 watchpoints are slower than real hardware watchpoints but are
2914 significantly faster than gdb software watchpoints.
2918 ** The register_pretty_printer function in module gdb.printing now takes
2919 an optional `replace' argument. If True, the new printer replaces any
2922 ** The "maint set python print-stack on|off" command has been
2923 deprecated and will be deleted in GDB 7.5.
2924 A new command: "set python print-stack none|full|message" has
2925 replaced it. Additionally, the default for "print-stack" is
2926 now "message", which just prints the error message without
2929 ** A prompt substitution hook (prompt_hook) is now available to the
2932 ** A new Python module, gdb.prompt has been added to the GDB Python
2933 modules library. This module provides functionality for
2934 escape sequences in prompts (used by set/show
2935 extended-prompt). These escape sequences are replaced by their
2936 corresponding value.
2938 ** Python commands and convenience-functions located in
2939 'data-directory'/python/gdb/command and
2940 'data-directory'/python/gdb/function are now automatically loaded
2943 ** Blocks now provide four new attributes. global_block and
2944 static_block will return the global and static blocks
2945 respectively. is_static and is_global are boolean attributes
2946 that indicate if the block is one of those two types.
2948 ** Symbols now provide the "type" attribute, the type of the symbol.
2950 ** The "gdb.breakpoint" function has been deprecated in favor of
2953 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2954 of a function. This class is based on the "finish" command
2955 available in the CLI.
2957 ** Type objects for struct and union types now allow access to
2958 the fields using standard Python dictionary (mapping) methods.
2959 For example, "some_type['myfield']" now works, as does
2960 "some_type.items()".
2962 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2965 ** A new function, "deep_items" has been added to the gdb.types
2966 module in the GDB Python modules library. This function returns
2967 an iterator over the fields of a struct or union type. Unlike
2968 the standard Python "iteritems" method, it will recursively traverse
2969 any anonymous fields.
2973 ** "*stopped" events can report several new "reason"s, such as
2976 ** Breakpoint changes are now notified using new async records, like
2977 "=breakpoint-modified".
2979 ** New command -ada-task-info.
2981 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2982 $sdir specifies the default system locations of shared libraries.
2983 $pdir specifies the directory where the libpthread used by the application
2986 GDB no longer looks in $sdir and $pdir after it has searched the directories
2987 mentioned in libthread-db-search-path. If you want to search those
2988 directories, they must be specified in libthread-db-search-path.
2989 The default value of libthread-db-search-path on GNU/Linux and Solaris
2990 systems is now "$sdir:$pdir".
2992 $pdir is not supported by gdbserver, it is currently ignored.
2993 $sdir is supported by gdbserver.
2995 * New configure option --with-iconv-bin.
2996 When using the internationalization support like the one in the GNU C
2997 library, GDB will invoke the "iconv" program to get a list of supported
2998 character sets. If this program lives in a non-standard location, one can
2999 use this option to specify where to find it.
3001 * When natively debugging programs on PowerPC BookE processors running
3002 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
3003 watchpoints, which specify a mask in addition to an address to watch.
3004 The mask specifies that some bits of an address (the bits which are
3005 reset in the mask) should be ignored when matching the address accessed
3006 by the inferior against the watchpoint address. See the "PowerPC Embedded"
3007 section in the user manual for more details.
3009 * The new option --once causes GDBserver to stop listening for connections once
3010 the first connection is made. The listening port used by GDBserver will
3011 become available after that.
3013 * New commands "info macros" and "alias" have been added.
3015 * New function parameters suffix @entry specifies value of function parameter
3016 at the time the function got called. Entry values are available only since
3022 "!" is now an alias of the "shell" command.
3023 Note that no space is needed between "!" and SHELL COMMAND.
3027 watch EXPRESSION mask MASK_VALUE
3028 The watch command now supports the mask argument which allows creation
3029 of masked watchpoints, if the current architecture supports this feature.
3031 info auto-load-scripts [REGEXP]
3032 This command was formerly named "maintenance print section-scripts".
3033 It is now generally useful and is no longer a maintenance-only command.
3035 info macro [-all] [--] MACRO
3036 The info macro command has new options `-all' and `--'. The first for
3037 printing all definitions of a macro. The second for explicitly specifying
3038 the end of arguments and the beginning of the macro name in case the macro
3039 name starts with a hyphen.
3041 collect[/s] EXPRESSIONS
3042 The tracepoint collect command now takes an optional modifier "/s"
3043 that directs it to dereference pointer-to-character types and
3044 collect the bytes of memory up to a zero byte. The behavior is
3045 similar to what you see when you use the regular print command on a
3046 string. An optional integer following the "/s" sets a bound on the
3047 number of bytes that will be collected.
3050 The trace start command now interprets any supplied arguments as a
3051 note to be recorded with the trace run, with an effect similar to
3052 setting the variable trace-notes.
3055 The trace stop command now interprets any arguments as a note to be
3056 mentioned along with the tstatus report that the trace was stopped
3057 with a command. The effect is similar to setting the variable
3060 * Tracepoints can now be enabled and disabled at any time after a trace
3061 experiment has been started using the standard "enable" and "disable"
3062 commands. It is now possible to start a trace experiment with no enabled
3063 tracepoints; GDB will display a warning, but will allow the experiment to
3064 begin, assuming that tracepoints will be enabled as needed while the trace
3067 * Fast tracepoints on 32-bit x86-architectures can now be placed at
3068 locations with 4-byte instructions, when they were previously
3069 limited to locations with instructions of 5 bytes or longer.
3073 set debug dwarf2-read
3074 show debug dwarf2-read
3075 Turns on or off display of debugging messages related to reading
3076 DWARF debug info. The default is off.
3078 set debug symtab-create
3079 show debug symtab-create
3080 Turns on or off display of debugging messages related to symbol table
3081 creation. The default is off.
3084 show extended-prompt
3085 Set the GDB prompt, and allow escape sequences to be inserted to
3086 display miscellaneous information (see 'help set extended-prompt'
3087 for the list of sequences). This prompt (and any information
3088 accessed through the escape sequences) is updated every time the
3089 prompt is displayed.
3091 set print entry-values (both|compact|default|if-needed|no|only|preferred)
3092 show print entry-values
3093 Set printing of frame argument values at function entry. In some cases
3094 GDB can determine the value of function argument which was passed by the
3095 function caller, even if the value was modified inside the called function.
3097 set debug entry-values
3098 show debug entry-values
3099 Control display of debugging info for determining frame argument values at
3100 function entry and virtual tail call frames.
3102 set basenames-may-differ
3103 show basenames-may-differ
3104 Set whether a source file may have multiple base names.
3105 (A "base name" is the name of a file with the directory part removed.
3106 Example: The base name of "/home/user/hello.c" is "hello.c".)
3107 If set, GDB will canonicalize file names (e.g., expand symlinks)
3108 before comparing them. Canonicalization is an expensive operation,
3109 but it allows the same file be known by more than one base name.
3110 If not set (the default), all source files are assumed to have just
3111 one base name, and gdb will do file name comparisons more efficiently.
3117 Set a user name and notes for the current and any future trace runs.
3118 This is useful for long-running and/or disconnected traces, to
3119 inform others (or yourself) as to who is running the trace, supply
3120 contact information, or otherwise explain what is going on.
3122 set trace-stop-notes
3123 show trace-stop-notes
3124 Set a note attached to the trace run, that is displayed when the
3125 trace has been stopped by a tstop command. This is useful for
3126 instance as an explanation, if you are stopping a trace run that was
3127 started by someone else.
3129 * New remote packets
3133 Dynamically enable a tracepoint in a started trace experiment.
3137 Dynamically disable a tracepoint in a started trace experiment.
3141 Set the user and notes of the trace run.
3145 Query the current status of a tracepoint.
3149 Query the minimum length of instruction at which a fast tracepoint may
3152 * Dcache size (number of lines) and line-size are now runtime-configurable
3153 via "set dcache line" and "set dcache line-size" commands.
3157 Texas Instruments TMS320C6x tic6x-*-*
3161 Renesas RL78 rl78-*-elf
3163 *** Changes in GDB 7.3.1
3165 * The build failure for NetBSD and OpenBSD targets have now been fixed.
3167 *** Changes in GDB 7.3
3169 * GDB has a new command: "thread find [REGEXP]".
3170 It finds the thread id whose name, target id, or thread extra info
3171 matches the given regular expression.
3173 * The "catch syscall" command now works on mips*-linux* targets.
3175 * The -data-disassemble MI command now supports modes 2 and 3 for
3176 dumping the instruction opcodes.
3178 * New command line options
3180 -data-directory DIR Specify DIR as the "data-directory".
3181 This is mostly for testing purposes.
3183 * The "maint set python auto-load on|off" command has been renamed to
3184 "set auto-load-scripts on|off".
3186 * GDB has a new command: "set directories".
3187 It is like the "dir" command except that it replaces the
3188 source path list instead of augmenting it.
3190 * GDB now understands thread names.
3192 On GNU/Linux, "info threads" will display the thread name as set by
3193 prctl or pthread_setname_np.
3195 There is also a new command, "thread name", which can be used to
3196 assign a name internally for GDB to display.
3199 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
3200 has been integrated into GDB.
3204 ** The function gdb.Write now accepts an optional keyword 'stream'.
3205 This keyword, when provided, will direct the output to either
3206 stdout, stderr, or GDB's logging output.
3208 ** Parameters can now be be sub-classed in Python, and in particular
3209 you may implement the get_set_doc and get_show_doc functions.
3210 This improves how Parameter set/show documentation is processed
3211 and allows for more dynamic content.
3213 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
3214 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
3215 have an is_valid method.
3217 ** Breakpoints can now be sub-classed in Python, and in particular
3218 you may implement a 'stop' function that is executed each time
3219 the inferior reaches that breakpoint.
3221 ** New function gdb.lookup_global_symbol looks up a global symbol.
3223 ** GDB values in Python are now callable if the value represents a
3224 function. For example, if 'some_value' represents a function that
3225 takes two integer parameters and returns a value, you can call
3226 that function like so:
3228 result = some_value (10,20)
3230 ** Module gdb.types has been added.
3231 It contains a collection of utilities for working with gdb.Types objects:
3232 get_basic_type, has_field, make_enum_dict.
3234 ** Module gdb.printing has been added.
3235 It contains utilities for writing and registering pretty-printers.
3236 New classes: PrettyPrinter, SubPrettyPrinter,
3237 RegexpCollectionPrettyPrinter.
3238 New function: register_pretty_printer.
3240 ** New commands "info pretty-printers", "enable pretty-printer" and
3241 "disable pretty-printer" have been added.
3243 ** gdb.parameter("directories") is now available.
3245 ** New function gdb.newest_frame returns the newest frame in the
3248 ** The gdb.InferiorThread class has a new "name" attribute. This
3249 holds the thread's name.
3251 ** Python Support for Inferior events.
3252 Python scripts can add observers to be notified of events
3253 occurring in the process being debugged.
3254 The following events are currently supported:
3255 - gdb.events.cont Continue event.
3256 - gdb.events.exited Inferior exited event.
3257 - gdb.events.stop Signal received, and Breakpoint hit events.
3261 ** GDB now puts template parameters in scope when debugging in an
3262 instantiation. For example, if you have:
3264 template<int X> int func (void) { return X; }
3266 then if you step into func<5>, "print X" will show "5". This
3267 feature requires proper debuginfo support from the compiler; it
3268 was added to GCC 4.5.
3270 ** The motion commands "next", "finish", "until", and "advance" now
3271 work better when exceptions are thrown. In particular, GDB will
3272 no longer lose control of the inferior; instead, the GDB will
3273 stop the inferior at the point at which the exception is caught.
3274 This functionality requires a change in the exception handling
3275 code that was introduced in GCC 4.5.
3277 * GDB now follows GCC's rules on accessing volatile objects when
3278 reading or writing target state during expression evaluation.
3279 One notable difference to prior behavior is that "print x = 0"
3280 no longer generates a read of x; the value of the assignment is
3281 now always taken directly from the value being assigned.
3283 * GDB now has some support for using labels in the program's source in
3284 linespecs. For instance, you can use "advance label" to continue
3285 execution to a label.
3287 * GDB now has support for reading and writing a new .gdb_index
3288 section. This section holds a fast index of DWARF debugging
3289 information and can be used to greatly speed up GDB startup and
3290 operation. See the documentation for `save gdb-index' for details.
3292 * The "watch" command now accepts an optional "-location" argument.
3293 When used, this causes GDB to watch the memory referred to by the
3294 expression. Such a watchpoint is never deleted due to it going out
3297 * GDB now supports thread debugging of core dumps on GNU/Linux.
3299 GDB now activates thread debugging using the libthread_db library
3300 when debugging GNU/Linux core dumps, similarly to when debugging
3301 live processes. As a result, when debugging a core dump file, GDB
3302 is now able to display pthread_t ids of threads. For example, "info
3303 threads" shows the same output as when debugging the process when it
3304 was live. In earlier releases, you'd see something like this:
3307 * 1 LWP 6780 main () at main.c:10
3309 While now you see this:
3312 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3314 It is also now possible to inspect TLS variables when debugging core
3317 When debugging a core dump generated on a machine other than the one
3318 used to run GDB, you may need to point GDB at the correct
3319 libthread_db library with the "set libthread-db-search-path"
3320 command. See the user manual for more details on this command.
3322 * When natively debugging programs on PowerPC BookE processors running
3323 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3324 which stop execution of the inferior whenever it executes an instruction
3325 at any address within the specified range. See the "PowerPC Embedded"
3326 section in the user manual for more details.
3328 * New features in the GDB remote stub, GDBserver
3330 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3331 and i686 LynxOS (version 5.x).
3333 ** GDBserver is now supported on Blackfin Linux.
3335 * New native configurations
3337 ia64 HP-UX ia64-*-hpux*
3341 Analog Devices, Inc. Blackfin Processor bfin-*
3343 * Ada task switching is now supported on sparc-elf targets when
3344 debugging a program using the Ravenscar Profile. For more information,
3345 see the "Tasking Support when using the Ravenscar Profile" section
3346 in the GDB user manual.
3348 * Guile support was removed.
3350 * New features in the GNU simulator
3352 ** The --map-info flag lists all known core mappings.
3354 ** CFI flashes may be simulated via the "cfi" device.
3356 *** Changes in GDB 7.2
3358 * Shared library support for remote targets by default
3360 When GDB is configured for a generic, non-OS specific target, like
3361 for example, --target=arm-eabi or one of the many *-*-elf targets,
3362 GDB now queries remote stubs for loaded shared libraries using the
3363 `qXfer:libraries:read' packet. Previously, shared library support
3364 was always disabled for such configurations.
3368 ** Argument Dependent Lookup (ADL)
3370 In C++ ADL lookup directs function search to the namespaces of its
3371 arguments even if the namespace has not been imported.
3381 Here the compiler will search for `foo' in the namespace of 'b'
3382 and find A::foo. GDB now supports this. This construct is commonly
3383 used in the Standard Template Library for operators.
3385 ** Improved User Defined Operator Support
3387 In addition to member operators, GDB now supports lookup of operators
3388 defined in a namespace and imported with a `using' directive, operators
3389 defined in the global scope, operators imported implicitly from an
3390 anonymous namespace, and the ADL operators mentioned in the previous
3392 GDB now also supports proper overload resolution for all the previously
3393 mentioned flavors of operators.
3395 ** static const class members
3397 Printing of static const class members that are initialized in the
3398 class definition has been fixed.
3400 * Windows Thread Information Block access.
3402 On Windows targets, GDB now supports displaying the Windows Thread
3403 Information Block (TIB) structure. This structure is visible either
3404 by using the new command `info w32 thread-information-block' or, by
3405 dereferencing the new convenience variable named `$_tlb', a
3406 thread-specific pointer to the TIB. This feature is also supported
3407 when remote debugging using GDBserver.
3409 * Static tracepoints
3411 Static tracepoints are calls in the user program into a tracing
3412 library. One such library is a port of the LTTng kernel tracer to
3413 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3414 When debugging with GDBserver, GDB now supports combining the GDB
3415 tracepoint machinery with such libraries. For example: the user can
3416 use GDB to probe a static tracepoint marker (a call from the user
3417 program into the tracing library) with the new "strace" command (see
3418 "New commands" below). This creates a "static tracepoint" in the
3419 breakpoint list, that can be manipulated with the same feature set
3420 as fast and regular tracepoints. E.g., collect registers, local and
3421 global variables, collect trace state variables, and define
3422 tracepoint conditions. In addition, the user can collect extra
3423 static tracepoint marker specific data, by collecting the new
3424 $_sdata internal variable. When analyzing the trace buffer, you can
3425 inspect $_sdata like any other variable available to GDB. For more
3426 information, see the "Tracepoints" chapter in GDB user manual. New
3427 remote packets have been defined to support static tracepoints, see
3428 the "New remote packets" section below.
3430 * Better reconstruction of tracepoints after disconnected tracing
3432 GDB will attempt to download the original source form of tracepoint
3433 definitions when starting a trace run, and then will upload these
3434 upon reconnection to the target, resulting in a more accurate
3435 reconstruction of the tracepoints that are in use on the target.
3439 You can now exercise direct control over the ways that GDB can
3440 affect your program. For instance, you can disallow the setting of
3441 breakpoints, so that the program can run continuously (assuming
3442 non-stop mode). In addition, the "observer" variable is available
3443 to switch all of the different controls; in observer mode, GDB
3444 cannot affect the target's behavior at all, which is useful for
3445 tasks like diagnosing live systems in the field.
3447 * The new convenience variable $_thread holds the number of the
3450 * New remote packets
3454 Return the address of the Windows Thread Information Block of a given thread.
3458 In response to several of the tracepoint packets, the target may now
3459 also respond with a number of intermediate `qRelocInsn' request
3460 packets before the final result packet, to have GDB handle
3461 relocating an instruction to execute at a different address. This
3462 is particularly useful for stubs that support fast tracepoints. GDB
3463 reports support for this feature in the qSupported packet.
3467 List static tracepoint markers in the target program.
3471 List static tracepoint markers at a given address in the target
3474 qXfer:statictrace:read
3476 Read the static trace data collected (by a `collect $_sdata'
3477 tracepoint action). The remote stub reports support for this packet
3478 to gdb's qSupported query.
3482 Send the current settings of GDB's permission flags.
3486 Send part of the source (textual) form of a tracepoint definition,
3487 which includes location, conditional, and action list.
3489 * The source command now accepts a -s option to force searching for the
3490 script in the source search path even if the script name specifies
3493 * New features in the GDB remote stub, GDBserver
3495 - GDBserver now support tracepoints (including fast tracepoints, and
3496 static tracepoints). The feature is currently supported by the
3497 i386-linux and amd64-linux builds. See the "Tracepoints support
3498 in gdbserver" section in the manual for more information.
3500 GDBserver JIT compiles the tracepoint's conditional agent
3501 expression bytecode into native code whenever possible for low
3502 overhead dynamic tracepoints conditionals. For such tracepoints,
3503 an expression that examines program state is evaluated when the
3504 tracepoint is reached, in order to determine whether to capture
3505 trace data. If the condition is simple and false, processing the
3506 tracepoint finishes very quickly and no data is gathered.
3508 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3509 for static tracepoints support.
3511 - GDBserver now supports x86_64 Windows 64-bit debugging.
3513 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3514 it understands register description.
3516 * The --batch flag now disables pagination and queries.
3518 * X86 general purpose registers
3520 GDB now supports reading/writing byte, word and double-word x86
3521 general purpose registers directly. This means you can use, say,
3522 $ah or $ax to refer, respectively, to the byte register AH and
3523 16-bit word register AX that are actually portions of the 32-bit
3524 register EAX or 64-bit register RAX.
3526 * The `commands' command now accepts a range of breakpoints to modify.
3527 A plain `commands' following a command that creates multiple
3528 breakpoints affects all the breakpoints set by that command. This
3529 applies to breakpoints set by `rbreak', and also applies when a
3530 single `break' command creates multiple breakpoints (e.g.,
3531 breakpoints on overloaded c++ functions).
3533 * The `rbreak' command now accepts a filename specification as part of
3534 its argument, limiting the functions selected by the regex to those
3535 in the specified file.
3537 * Support for remote debugging Windows and SymbianOS shared libraries
3538 from Unix hosts has been improved. Non Windows GDB builds now can
3539 understand target reported file names that follow MS-DOS based file
3540 system semantics, such as file names that include drive letters and
3541 use the backslash character as directory separator. This makes it
3542 possible to transparently use the "set sysroot" and "set
3543 solib-search-path" on Unix hosts to point as host copies of the
3544 target's shared libraries. See the new command "set
3545 target-file-system-kind" described below, and the "Commands to
3546 specify files" section in the user manual for more information.
3550 eval template, expressions...
3551 Convert the values of one or more expressions under the control
3552 of the string template to a command line, and call it.
3554 set target-file-system-kind unix|dos-based|auto
3555 show target-file-system-kind
3556 Set or show the assumed file system kind for target reported file
3559 save breakpoints <filename>
3560 Save all current breakpoint definitions to a file suitable for use
3561 in a later debugging session. To read the saved breakpoint
3562 definitions, use the `source' command.
3564 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3567 info static-tracepoint-markers
3568 Display information about static tracepoint markers in the target.
3570 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3571 Define a static tracepoint by probing a marker at the given
3572 function, line, address, or marker ID.
3576 Enable and disable observer mode.
3578 set may-write-registers on|off
3579 set may-write-memory on|off
3580 set may-insert-breakpoints on|off
3581 set may-insert-tracepoints on|off
3582 set may-insert-fast-tracepoints on|off
3583 set may-interrupt on|off
3584 Set individual permissions for GDB effects on the target. Note that
3585 some of these settings can have undesirable or surprising
3586 consequences, particularly when changed in the middle of a session.
3587 For instance, disabling the writing of memory can prevent
3588 breakpoints from being inserted, cause single-stepping to fail, or
3589 even crash your program, if you disable after breakpoints have been
3590 inserted. However, GDB should not crash.
3592 set record memory-query on|off
3593 show record memory-query
3594 Control whether to stop the inferior if memory changes caused
3595 by an instruction cannot be recorded.
3600 The disassemble command now supports "start,+length" form of two arguments.
3604 ** GDB now provides a new directory location, called the python directory,
3605 where Python scripts written for GDB can be installed. The location
3606 of that directory is <data-directory>/python, where <data-directory>
3607 is the GDB data directory. For more details, see section `Scripting
3608 GDB using Python' in the manual.
3610 ** The GDB Python API now has access to breakpoints, symbols, symbol
3611 tables, program spaces, inferiors, threads and frame's code blocks.
3612 Additionally, GDB Parameters can now be created from the API, and
3613 manipulated via set/show in the CLI.
3615 ** New functions gdb.target_charset, gdb.target_wide_charset,
3616 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3618 ** New exception gdb.GdbError.
3620 ** Pretty-printers are now also looked up in the current program space.
3622 ** Pretty-printers can now be individually enabled and disabled.
3624 ** GDB now looks for names of Python scripts to auto-load in a
3625 special section named `.debug_gdb_scripts', in addition to looking
3626 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3628 * Tracepoint actions were unified with breakpoint commands. In particular,
3629 there are no longer differences in "info break" output for breakpoints and
3630 tracepoints and the "commands" command can be used for both tracepoints and
3631 regular breakpoints.
3635 ARM Symbian arm*-*-symbianelf*
3637 * D language support.
3638 GDB now supports debugging programs written in the D programming
3641 * GDB now supports the extended ptrace interface for PowerPC which is
3642 available since Linux kernel version 2.6.34. This automatically enables
3643 any hardware breakpoints and additional hardware watchpoints available in
3644 the processor. The old ptrace interface exposes just one hardware
3645 watchpoint and no hardware breakpoints.
3647 * GDB is now able to use the Data Value Compare (DVC) register available on
3648 embedded PowerPC processors to implement in hardware simple watchpoint
3649 conditions of the form:
3651 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3653 This works in native GDB running on Linux kernels with the extended ptrace
3654 interface mentioned above.
3656 *** Changes in GDB 7.1
3660 ** Namespace Support
3662 GDB now supports importing of namespaces in C++. This enables the
3663 user to inspect variables from imported namespaces. Support for
3664 namepace aliasing has also been added. So, if a namespace is
3665 aliased in the current scope (e.g. namepace C=A; ) the user can
3666 print variables using the alias (e.g. (gdb) print C::x).
3670 All known bugs relating to the printing of virtual base class were
3671 fixed. It is now possible to call overloaded static methods using a
3676 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3677 and reinterpret_cast<> are now handled by the C++ expression parser.
3681 Xilinx MicroBlaze microblaze-*-*
3686 Xilinx MicroBlaze microblaze
3689 * Multi-program debugging.
3691 GDB now has support for multi-program (a.k.a. multi-executable or
3692 multi-exec) debugging. This allows for debugging multiple inferiors
3693 simultaneously each running a different program under the same GDB
3694 session. See "Debugging Multiple Inferiors and Programs" in the
3695 manual for more information. This implied some user visible changes
3696 in the multi-inferior support. For example, "info inferiors" now
3697 lists inferiors that are not running yet or that have exited
3698 already. See also "New commands" and "New options" below.
3700 * New tracing features
3702 GDB's tracepoint facility now includes several new features:
3704 ** Trace state variables
3706 GDB tracepoints now include support for trace state variables, which
3707 are variables managed by the target agent during a tracing
3708 experiment. They are useful for tracepoints that trigger each
3709 other, so for instance one tracepoint can count hits in a variable,
3710 and then a second tracepoint has a condition that is true when the
3711 count reaches a particular value. Trace state variables share the
3712 $-syntax of GDB convenience variables, and can appear in both
3713 tracepoint actions and condition expressions. Use the "tvariable"
3714 command to create, and "info tvariables" to view; see "Trace State
3715 Variables" in the manual for more detail.
3719 GDB now includes an option for defining fast tracepoints, which
3720 targets may implement more efficiently, such as by installing a jump
3721 into the target agent rather than a trap instruction. The resulting
3722 speedup can be by two orders of magnitude or more, although the
3723 tradeoff is that some program locations on some target architectures
3724 might not allow fast tracepoint installation, for instance if the
3725 instruction to be replaced is shorter than the jump. To request a
3726 fast tracepoint, use the "ftrace" command, with syntax identical to
3727 the regular trace command.
3729 ** Disconnected tracing
3731 It is now possible to detach GDB from the target while it is running
3732 a trace experiment, then reconnect later to see how the experiment
3733 is going. In addition, a new variable disconnected-tracing lets you
3734 tell the target agent whether to continue running a trace if the
3735 connection is lost unexpectedly.
3739 GDB now has the ability to save the trace buffer into a file, and
3740 then use that file as a target, similarly to you can do with
3741 corefiles. You can select trace frames, print data that was
3742 collected in them, and use tstatus to display the state of the
3743 tracing run at the moment that it was saved. To create a trace
3744 file, use "tsave <filename>", and to use it, do "target tfile
3747 ** Circular trace buffer
3749 You can ask the target agent to handle the trace buffer as a
3750 circular buffer, discarding the oldest trace frames to make room for
3751 newer ones, by setting circular-trace-buffer to on. This feature may
3752 not be available for all target agents.
3757 The disassemble command, when invoked with two arguments, now requires
3758 the arguments to be comma-separated.
3761 The info variables command now displays variable definitions. Files
3762 which only declare a variable are not shown.
3765 The source command is now capable of sourcing Python scripts.
3766 This feature is dependent on the debugger being build with Python
3769 Related to this enhancement is also the introduction of a new command
3770 "set script-extension" (see below).
3772 * New commands (for set/show, see "New options" below)
3774 record save [<FILENAME>]
3775 Save a file (in core file format) containing the process record
3776 execution log for replay debugging at a later time.
3778 record restore <FILENAME>
3779 Restore the process record execution log that was saved at an
3780 earlier time, for replay debugging.
3782 add-inferior [-copies <N>] [-exec <FILENAME>]
3785 clone-inferior [-copies <N>] [ID]
3786 Make a new inferior ready to execute the same program another
3787 inferior has loaded.
3792 maint info program-spaces
3793 List the program spaces loaded into GDB.
3795 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3796 show remote interrupt-sequence
3797 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3798 as the sequence to the remote target in order to interrupt the execution.
3799 Ctrl-C is a default. Some system prefers BREAK which is high level of
3800 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3801 Magic SysRq g. It is BREAK signal and character 'g'.
3803 set remote interrupt-on-connect [on | off]
3804 show remote interrupt-on-connect
3805 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3806 remote target when gdb connects to it. This is needed when you debug
3809 set remotebreak [on | off]
3811 Deprecated. Use "set/show remote interrupt-sequence" instead.
3813 tvariable $NAME [ = EXP ]
3814 Create or modify a trace state variable.
3817 List trace state variables and their values.
3819 delete tvariable $NAME ...
3820 Delete one or more trace state variables.
3823 Evaluate the given expressions without collecting anything into the
3824 trace buffer. (Valid in tracepoint actions only.)
3826 ftrace FN / FILE:LINE / *ADDR
3827 Define a fast tracepoint at the given function, line, or address.
3829 * New expression syntax
3831 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3832 GDB now parses 0b101010 identically with 42.
3836 set follow-exec-mode new|same
3837 show follow-exec-mode
3838 Control whether GDB reuses the same inferior across an exec call or
3839 creates a new one. This is useful to be able to restart the old
3840 executable after the inferior having done an exec call.
3842 set default-collect EXPR, ...
3843 show default-collect
3844 Define a list of expressions to be collected at each tracepoint.
3845 This is a useful way to ensure essential items are not overlooked,
3846 such as registers or a critical global variable.
3848 set disconnected-tracing
3849 show disconnected-tracing
3850 If set to 1, the target is instructed to continue tracing if it
3851 loses its connection to GDB. If 0, the target is to stop tracing
3854 set circular-trace-buffer
3855 show circular-trace-buffer
3856 If set to on, the target is instructed to use a circular trace buffer
3857 and discard the oldest trace frames instead of stopping the trace due
3858 to a full trace buffer. If set to off, the trace stops when the buffer
3859 fills up. Some targets may not support this.
3861 set script-extension off|soft|strict
3862 show script-extension
3863 If set to "off", the debugger does not perform any script language
3864 recognition, and all sourced files are assumed to be GDB scripts.
3865 If set to "soft" (the default), files are sourced according to
3866 filename extension, falling back to GDB scripts if the first
3868 If set to "strict", files are sourced according to filename extension.
3870 set ada trust-PAD-over-XVS on|off
3871 show ada trust-PAD-over-XVS
3872 If off, activate a workaround against a bug in the debugging information
3873 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3874 the GCC sources for more information about the GNAT encoding and
3875 PAD types in particular). It is always safe to set this option to
3876 off, but this introduces a slight performance penalty. The default
3879 * Python API Improvements
3881 ** GDB provides the new class gdb.LazyString. This is useful in
3882 some pretty-printing cases. The new method gdb.Value.lazy_string
3883 provides a simple way to create objects of this type.
3885 ** The fields returned by gdb.Type.fields now have an
3886 `is_base_class' attribute.
3888 ** The new method gdb.Type.range returns the range of an array type.
3890 ** The new method gdb.parse_and_eval can be used to parse and
3891 evaluate an expression.
3893 * New remote packets
3896 Define a trace state variable.
3899 Get the current value of a trace state variable.
3902 Set desired tracing behavior upon disconnection.
3905 Set the trace buffer to be linear or circular.
3908 Get data about the tracepoints currently in use.
3912 Process record now works correctly with hardware watchpoints.
3914 Multiple bug fixes have been made to the mips-irix port, making it
3915 much more reliable. In particular:
3916 - Debugging threaded applications is now possible again. Previously,
3917 GDB would hang while starting the program, or while waiting for
3918 the program to stop at a breakpoint.
3919 - Attaching to a running process no longer hangs.
3920 - An error occurring while loading a core file has been fixed.
3921 - Changing the value of the PC register now works again. This fixes
3922 problems observed when using the "jump" command, or when calling
3923 a function from GDB, or even when assigning a new value to $pc.
3924 - With the "finish" and "return" commands, the return value for functions
3925 returning a small array is now correctly printed.
3926 - It is now possible to break on shared library code which gets executed
3927 during a shared library init phase (code executed while executing
3928 their .init section). Previously, the breakpoint would have no effect.
3929 - GDB is now able to backtrace through the signal handler for
3930 non-threaded programs.
3932 PIE (Position Independent Executable) programs debugging is now supported.
3933 This includes debugging execution of PIC (Position Independent Code) shared
3934 libraries although for that, it should be possible to run such libraries as an
3937 *** Changes in GDB 7.0
3939 * GDB now has an interface for JIT compilation. Applications that
3940 dynamically generate code can create symbol files in memory and register
3941 them with GDB. For users, the feature should work transparently, and
3942 for JIT developers, the interface is documented in the GDB manual in the
3943 "JIT Compilation Interface" chapter.
3945 * Tracepoints may now be conditional. The syntax is as for
3946 breakpoints; either an "if" clause appended to the "trace" command,
3947 or the "condition" command is available. GDB sends the condition to
3948 the target for evaluation using the same bytecode format as is used
3949 for tracepoint actions.
3951 * The disassemble command now supports: an optional /r modifier, print the
3952 raw instructions in hex as well as in symbolic form, and an optional /m
3953 modifier to print mixed source+assembly.
3955 * Process record and replay
3957 In a architecture environment that supports ``process record and
3958 replay'', ``process record and replay'' target can record a log of
3959 the process execution, and replay it with both forward and reverse
3962 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3963 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3964 set execution-direction {forward|reverse}, for targets that support
3967 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3968 feature is available with a native GDB running on kernel version
3971 * GDB now has support for multi-byte and wide character sets on the
3972 target. Strings whose character type is wchar_t, char16_t, or
3973 char32_t are now correctly printed. GDB supports wide- and unicode-
3974 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3975 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3976 `printf'. This feature requires iconv to work properly; if your
3977 system does not have a working iconv, GDB can use GNU libiconv. See
3978 the installation instructions for more information.
3980 * GDB now supports automatic retrieval of shared library files from
3981 remote targets. To use this feature, specify a system root that begins
3982 with the `remote:' prefix, either via the `set sysroot' command or via
3983 the `--with-sysroot' configure-time option.
3985 * "info sharedlibrary" now takes an optional regex of libraries to show,
3986 and it now reports if a shared library has no debugging information.
3988 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3989 now complete on file names.
3991 * When completing in expressions, gdb will attempt to limit
3992 completions to allowable structure or union fields, where appropriate.
3993 For instance, consider:
3995 # struct example { int f1; double f2; };
3996 # struct example variable;
3999 If the user types TAB at the end of this command line, the available
4000 completions will be "f1" and "f2".
4002 * Inlined functions are now supported. They show up in backtraces, and
4003 the "step", "next", and "finish" commands handle them automatically.
4005 * GDB now supports the token-splicing (##) and stringification (#)
4006 operators when expanding macros. It also supports variable-arity
4009 * GDB now supports inspecting extra signal information, exported by
4010 the new $_siginfo convenience variable. The feature is currently
4011 implemented on linux ARM, i386 and amd64.
4013 * GDB can now display the VFP floating point registers and NEON vector
4014 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
4015 can provide these registers (requires Linux 2.6.30 or later). Remote
4016 and simulator targets may also provide them.
4018 * New remote packets
4021 Search memory for a sequence of bytes.
4024 Turn off `+'/`-' protocol acknowledgments to permit more efficient
4025 operation over reliable transport links. Use of this packet is
4026 controlled by the `set remote noack-packet' command.
4029 Kill the process with the specified process ID. Use this in preference
4030 to `k' when multiprocess protocol extensions are supported.
4033 Obtains additional operating system information
4037 Read or write additional signal information.
4039 * Removed remote protocol undocumented extension
4041 An undocumented extension to the remote protocol's `S' stop reply
4042 packet that permited the stub to pass a process id was removed.
4043 Remote servers should use the `T' stop reply packet instead.
4045 * GDB now supports multiple function calling conventions according to the
4046 DWARF-2 DW_AT_calling_convention function attribute.
4048 * The SH target utilizes the aforementioned change to distinguish between gcc
4049 and Renesas calling convention. It also adds the new CLI commands
4050 `set/show sh calling-convention'.
4052 * GDB can now read compressed debug sections, as produced by GNU gold
4053 with the --compress-debug-sections=zlib flag.
4055 * 64-bit core files are now supported on AIX.
4057 * Thread switching is now supported on Tru64.
4059 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
4060 which will be allocated using malloc later in program execution.
4062 * The qXfer:libraries:read remote procotol packet now allows passing a
4063 list of section offsets.
4065 * On GNU/Linux, GDB can now attach to stopped processes. Several race
4066 conditions handling signals delivered during attach or thread creation
4067 have also been fixed.
4069 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
4070 From the user's standpoint, all unqualified instances of True and False
4071 are treated as the standard definitions, regardless of context.
4073 * GDB now parses C++ symbol and type names more flexibly. For
4076 template<typename T> class C { };
4079 GDB will now correctly handle all of:
4081 ptype C<char const *>
4082 ptype C<char const*>
4083 ptype C<const char *>
4084 ptype C<const char*>
4086 * New features in the GDB remote stub, gdbserver
4088 - The "--wrapper" command-line argument tells gdbserver to use a
4089 wrapper program to launch programs for debugging.
4091 - On PowerPC and S/390 targets, it is now possible to use a single
4092 gdbserver executable to debug both 32-bit and 64-bit programs.
4093 (This requires gdbserver itself to be built as a 64-bit executable.)
4095 - gdbserver uses the new noack protocol mode for TCP connections to
4096 reduce communications latency, if also supported and enabled in GDB.
4098 - Support for the sparc64-linux-gnu target is now included in
4101 - The amd64-linux build of gdbserver now supports debugging both
4102 32-bit and 64-bit programs.
4104 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
4105 now support hardware watchpoints, and will use them automatically
4110 GDB now has support for scripting using Python. Whether this is
4111 available is determined at configure time.
4113 New GDB commands can now be written in Python.
4115 * Ada tasking support
4117 Ada tasks can now be inspected in GDB. The following commands have
4121 Print the list of Ada tasks.
4123 Print detailed information about task number N.
4125 Print the task number of the current task.
4127 Switch the context of debugging to task number N.
4129 * Support for user-defined prefixed commands. The "define" command can
4130 add new commands to existing prefixes, e.g. "target".
4132 * Multi-inferior, multi-process debugging.
4134 GDB now has generalized support for multi-inferior debugging. See
4135 "Debugging Multiple Inferiors" in the manual for more information.
4136 Although availability still depends on target support, the command
4137 set is more uniform now. The GNU/Linux specific multi-forks support
4138 has been migrated to this new framework. This implied some user
4139 visible changes; see "New commands" and also "Removed commands"
4142 * Target descriptions can now describe the target OS ABI. See the
4143 "Target Description Format" section in the user manual for more
4146 * Target descriptions can now describe "compatible" architectures
4147 to indicate that the target can execute applications for a different
4148 architecture in addition to those for the main target architecture.
4149 See the "Target Description Format" section in the user manual for
4152 * Multi-architecture debugging.
4154 GDB now includes general supports for debugging applications on
4155 hybrid systems that use more than one single processor architecture
4156 at the same time. Each such hybrid architecture still requires
4157 specific support to be added. The only hybrid architecture supported
4158 in this version of GDB is the Cell Broadband Engine.
4160 * GDB now supports integrated debugging of Cell/B.E. applications that
4161 use both the PPU and SPU architectures. To enable support for hybrid
4162 Cell/B.E. debugging, you need to configure GDB to support both the
4163 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
4164 --enable-targets configure option.
4166 * Non-stop mode debugging.
4168 For some targets, GDB now supports an optional mode of operation in
4169 which you can examine stopped threads while other threads continue
4170 to execute freely. This is referred to as non-stop mode, with the
4171 old mode referred to as all-stop mode. See the "Non-Stop Mode"
4172 section in the user manual for more information.
4174 To be able to support remote non-stop debugging, a remote stub needs
4175 to implement the non-stop mode remote protocol extensions, as
4176 described in the "Remote Non-Stop" section of the user manual. The
4177 GDB remote stub, gdbserver, has been adjusted to support these
4178 extensions on linux targets.
4180 * New commands (for set/show, see "New options" below)
4182 catch syscall [NAME(S) | NUMBER(S)]
4183 Catch system calls. Arguments, which should be names of system
4184 calls or their numbers, mean catch only those syscalls. Without
4185 arguments, every syscall will be caught. When the inferior issues
4186 any of the specified syscalls, GDB will stop and announce the system
4187 call, both when it is called and when its call returns. This
4188 feature is currently available with a native GDB running on the
4189 Linux Kernel, under the following architectures: x86, x86_64,
4190 PowerPC and PowerPC64.
4192 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
4194 Search memory for a sequence of bytes.
4196 maint set python print-stack
4197 maint show python print-stack
4198 Show a stack trace when an error is encountered in a Python script.
4201 Invoke CODE by passing it to the Python interpreter.
4206 These allow macros to be defined, undefined, and listed
4210 Show operating system information about processes.
4213 List the inferiors currently under GDB's control.
4216 Switch focus to inferior number NUM.
4219 Detach from inferior number NUM.
4222 Kill inferior number NUM.
4226 set spu stop-on-load
4227 show spu stop-on-load
4228 Control whether to stop for new SPE threads during Cell/B.E. debugging.
4230 set spu auto-flush-cache
4231 show spu auto-flush-cache
4232 Control whether to automatically flush the software-managed cache
4233 during Cell/B.E. debugging.
4235 set sh calling-convention
4236 show sh calling-convention
4237 Control the calling convention used when calling SH target functions.
4240 show debug timestamp
4241 Control display of timestamps with GDB debugging output.
4243 set disassemble-next-line
4244 show disassemble-next-line
4245 Control display of disassembled source lines or instructions when
4248 set remote noack-packet
4249 show remote noack-packet
4250 Set/show the use of remote protocol QStartNoAckMode packet. See above
4251 under "New remote packets."
4253 set remote query-attached-packet
4254 show remote query-attached-packet
4255 Control use of remote protocol `qAttached' (query-attached) packet.
4257 set remote read-siginfo-object
4258 show remote read-siginfo-object
4259 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4262 set remote write-siginfo-object
4263 show remote write-siginfo-object
4264 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4267 set remote reverse-continue
4268 show remote reverse-continue
4269 Control use of remote protocol 'bc' (reverse-continue) packet.
4271 set remote reverse-step
4272 show remote reverse-step
4273 Control use of remote protocol 'bs' (reverse-step) packet.
4275 set displaced-stepping
4276 show displaced-stepping
4277 Control displaced stepping mode. Displaced stepping is a way to
4278 single-step over breakpoints without removing them from the debuggee.
4279 Also known as "out-of-line single-stepping".
4282 show debug displaced
4283 Control display of debugging info for displaced stepping.
4285 maint set internal-error
4286 maint show internal-error
4287 Control what GDB does when an internal error is detected.
4289 maint set internal-warning
4290 maint show internal-warning
4291 Control what GDB does when an internal warning is detected.
4296 Use a wrapper program to launch programs for debugging.
4298 set multiple-symbols (all|ask|cancel)
4299 show multiple-symbols
4300 The value of this variable can be changed to adjust the debugger behavior
4301 when an expression or a breakpoint location contains an ambiguous symbol
4302 name (an overloaded function name, for instance).
4304 set breakpoint always-inserted
4305 show breakpoint always-inserted
4306 Keep breakpoints always inserted in the target, as opposed to inserting
4307 them when resuming the target, and removing them when the target stops.
4308 This option can improve debugger performance on slow remote targets.
4310 set arm fallback-mode (arm|thumb|auto)
4311 show arm fallback-mode
4312 set arm force-mode (arm|thumb|auto)
4314 These commands control how ARM GDB determines whether instructions
4315 are ARM or Thumb. The default for both settings is auto, which uses
4316 the current CPSR value for instructions without symbols; previous
4317 versions of GDB behaved as if "set arm fallback-mode arm".
4319 set disable-randomization
4320 show disable-randomization
4321 Standalone programs run with the virtual address space randomization enabled
4322 by default on some platforms. This option keeps the addresses stable across
4323 multiple debugging sessions.
4327 Control whether other threads are stopped or not when some thread hits
4332 Requests that asynchronous execution is enabled in the target, if available.
4333 In this case, it's possible to resume target in the background, and interact
4334 with GDB while the target is running. "show target-async" displays the
4335 current state of asynchronous execution of the target.
4337 set target-wide-charset
4338 show target-wide-charset
4339 The target-wide-charset is the name of the character set that GDB
4340 uses when printing characters whose type is wchar_t.
4342 set tcp auto-retry (on|off)
4344 set tcp connect-timeout
4345 show tcp connect-timeout
4346 These commands allow GDB to retry failed TCP connections to a remote stub
4347 with a specified timeout period; this is useful if the stub is launched
4348 in parallel with GDB but may not be ready to accept connections immediately.
4350 set libthread-db-search-path
4351 show libthread-db-search-path
4352 Control list of directories which GDB will search for appropriate
4355 set schedule-multiple (on|off)
4356 show schedule-multiple
4357 Allow GDB to resume all threads of all processes or only threads of
4358 the current process.
4362 Use more aggressive caching for accesses to the stack. This improves
4363 performance of remote debugging (particularly backtraces) without
4364 affecting correctness.
4366 set interactive-mode (on|off|auto)
4367 show interactive-mode
4368 Control whether GDB runs in interactive mode (on) or not (off).
4369 When in interactive mode, GDB waits for the user to answer all
4370 queries. Otherwise, GDB does not wait and assumes the default
4371 answer. When set to auto (the default), GDB determines which
4372 mode to use based on the stdin settings.
4377 For program forks, this is replaced by the new more generic `info
4378 inferiors' command. To list checkpoints, you can still use the
4379 `info checkpoints' command, which was an alias for the `info forks'
4383 Replaced by the new `inferior' command. To switch between
4384 checkpoints, you can still use the `restart' command, which was an
4385 alias for the `fork' command.
4388 This is removed, since some targets don't have a notion of
4389 processes. To switch between processes, you can still use the
4390 `inferior' command using GDB's own inferior number.
4393 For program forks, this is replaced by the new more generic `kill
4394 inferior' command. To delete a checkpoint, you can still use the
4395 `delete checkpoint' command, which was an alias for the `delete
4399 For program forks, this is replaced by the new more generic `detach
4400 inferior' command. To detach a checkpoint, you can still use the
4401 `detach checkpoint' command, which was an alias for the `detach
4404 * New native configurations
4406 x86/x86_64 Darwin i[34567]86-*-darwin*
4408 x86_64 MinGW x86_64-*-mingw*
4412 Lattice Mico32 lm32-*
4413 x86 DICOS i[34567]86-*-dicos*
4414 x86_64 DICOS x86_64-*-dicos*
4417 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4418 (mingw32ce) debugging.
4424 These commands were actually not implemented on any target.
4426 *** Changes in GDB 6.8
4428 * New native configurations
4430 NetBSD/hppa hppa*-*netbsd*
4431 Xtensa GNU/Linux xtensa*-*-linux*
4435 NetBSD/hppa hppa*-*-netbsd*
4436 Xtensa GNU/Lunux xtensa*-*-linux*
4438 * Change in command line behavior -- corefiles vs. process ids.
4440 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4441 attaching to process NUMBER fails, GDB no longer attempts to open a
4442 core file named NUMBER. Attaching to a program using the -c option
4443 is no longer supported. Instead, use the '-p' or '--pid' options.
4445 * GDB can now be built as a native debugger for debugging Windows x86
4446 (mingw32) Portable Executable (PE) programs.
4448 * Pending breakpoints no longer change their number when their address
4451 * GDB now supports breakpoints with multiple locations,
4452 including breakpoints on C++ constructors, inside C++ templates,
4453 and in inlined functions.
4455 * GDB's ability to debug optimized code has been improved. GDB more
4456 accurately identifies function bodies and lexical blocks that occupy
4457 more than one contiguous range of addresses.
4459 * Target descriptions can now describe registers for PowerPC.
4461 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4462 registers on PowerPC targets.
4464 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4465 targets even when the libthread_db library is not available.
4467 * The GDB remote stub, gdbserver, now supports the new file transfer
4468 commands (remote put, remote get, and remote delete).
4470 * The GDB remote stub, gdbserver, now supports run and attach in
4471 extended-remote mode.
4473 * hppa*64*-*-hpux11* target broken
4474 The debugger is unable to start a program and fails with the following
4475 error: "Error trying to get information about dynamic linker".
4476 The gdb-6.7 release is also affected.
4478 * GDB now supports the --enable-targets= configure option to allow
4479 building a single GDB executable that supports multiple remote
4480 target architectures.
4482 * GDB now supports debugging C and C++ programs which use the
4483 Decimal Floating Point extension. In addition, the PowerPC target
4484 now has a set of pseudo-registers to inspect decimal float values
4485 stored in two consecutive float registers.
4487 * The -break-insert MI command can optionally create pending
4490 * Improved support for debugging Ada
4491 Many improvements to the Ada language support have been made. These
4493 - Better support for Ada2005 interface types
4494 - Improved handling of arrays and slices in general
4495 - Better support for Taft-amendment types
4496 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4498 - Improved command completion in Ada
4501 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4506 set print frame-arguments (all|scalars|none)
4507 show print frame-arguments
4508 The value of this variable can be changed to control which argument
4509 values should be printed by the debugger when displaying a frame.
4514 Transfer files to and from a remote target, and delete remote files.
4521 Transfer files to and from a remote target, and delete remote files.
4523 * New remote packets
4530 Open, close, read, write, and delete files on the remote system.
4533 Attach to an existing process on the remote system, in extended-remote
4537 Run a new process on the remote system, in extended-remote mode.
4539 *** Changes in GDB 6.7
4541 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4542 bfd, libiberty and opcodes, as revealed by static analysis donated by
4543 Coverity, Inc. (http://scan.coverity.com).
4545 * When looking up multiply-defined global symbols, GDB will now prefer the
4546 symbol definition in the current shared library if it was built using the
4547 -Bsymbolic linker option.
4549 * When the Text User Interface (TUI) is not configured, GDB will now
4550 recognize the -tui command-line option and print a message that the TUI
4553 * The GDB remote stub, gdbserver, now has lower overhead for high
4554 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4556 * GDB for MIPS targets now autodetects whether a remote target provides
4557 32-bit or 64-bit register values.
4559 * Support for C++ member pointers has been improved.
4561 * GDB now understands XML target descriptions, which specify the
4562 target's overall architecture. GDB can read a description from
4563 a local file or over the remote serial protocol.
4565 * Vectors of single-byte data use a new integer type which is not
4566 automatically displayed as character or string data.
4568 * The /s format now works with the print command. It displays
4569 arrays of single-byte integers and pointers to single-byte integers
4572 * Target descriptions can now describe target-specific registers,
4573 for architectures which have implemented the support (currently
4574 only ARM, M68K, and MIPS).
4576 * GDB and the GDB remote stub, gdbserver, now support the XScale
4579 * The GDB remote stub, gdbserver, has been updated to support
4580 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4581 has been rewritten to use the standard GDB remote protocol.
4583 * GDB can now step into C++ functions which are called through thunks.
4585 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4587 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4588 layout. It also supports a TextSeg= and DataSeg= response when only
4589 segment base addresses (rather than offsets) are available.
4591 * The /i format now outputs any trailing branch delay slot instructions
4592 immediately following the last instruction within the count specified.
4594 * The GDB remote protocol "T" stop reply packet now supports a
4595 "library" response. Combined with the new "qXfer:libraries:read"
4596 packet, this response allows GDB to debug shared libraries on targets
4597 where the operating system manages the list of loaded libraries (e.g.
4598 Windows and SymbianOS).
4600 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4601 (DLLs) on Windows and Windows CE targets.
4603 * GDB now supports a faster verification that a .debug file matches its binary
4604 according to its build-id signature, if the signature is present.
4610 Enable or disable hardware flow control (RTS/CTS) on the serial port
4611 when debugging using remote targets.
4613 set mem inaccessible-by-default
4614 show mem inaccessible-by-default
4615 If the target supplies a memory map, for instance via the remote
4616 protocol's "qXfer:memory-map:read" packet, setting this variable
4617 prevents GDB from accessing memory outside the memory map. This
4618 is useful for targets with memory mapped registers or which react
4619 badly to accesses of unmapped address space.
4621 set breakpoint auto-hw
4622 show breakpoint auto-hw
4623 If the target supplies a memory map, for instance via the remote
4624 protocol's "qXfer:memory-map:read" packet, setting this variable
4625 lets GDB use hardware breakpoints automatically for memory regions
4626 where it can not use software breakpoints. This covers both the
4627 "break" command and internal breakpoints used for other commands
4628 including "next" and "finish".
4631 catch exception unhandled
4632 Stop the program execution when Ada exceptions are raised.
4635 Stop the program execution when an Ada assertion failed.
4639 Set an alternate system root for target files. This is a more
4640 general version of "set solib-absolute-prefix", which is now
4641 an alias to "set sysroot".
4644 Provide extended SPU facility status information. This set of
4645 commands is available only when debugging the Cell/B.E. SPU
4648 * New native configurations
4650 OpenBSD/sh sh*-*openbsd*
4653 unset tdesc filename
4655 Use the specified local file as an XML target description, and do
4656 not query the target for its built-in description.
4660 OpenBSD/sh sh*-*-openbsd*
4661 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4662 Toshiba Media Processor mep-elf
4664 * New remote packets
4667 Ignore the specified signals; pass them directly to the debugged program
4668 without stopping other threads or reporting them to GDB.
4670 qXfer:features:read:
4671 Read an XML target description from the target, which describes its
4676 Read or write contents of an spufs file on the target system. These
4677 packets are available only on the Cell/B.E. SPU architecture.
4679 qXfer:libraries:read:
4680 Report the loaded shared libraries. Combined with new "T" packet
4681 response, this packet allows GDB to debug shared libraries on
4682 targets where the operating system manages the list of loaded
4683 libraries (e.g. Windows and SymbianOS).
4687 Support for these obsolete configurations has been removed.
4695 i[34567]86-*-lynxos*
4696 i[34567]86-*-netware*
4697 i[34567]86-*-sco3.2v5*
4698 i[34567]86-*-sco3.2v4*
4700 i[34567]86-*-sysv4.2*
4703 i[34567]86-*-unixware2*
4704 i[34567]86-*-unixware*
4713 * Other removed features
4720 Various m68k-only ROM monitors.
4727 Various Renesas ROM monitors and debugging interfaces for SH and
4732 Support for a Macraigor serial interface to on-chip debugging.
4733 GDB does not directly support the newer parallel or USB
4738 A debug information format. The predecessor to DWARF 2 and
4739 DWARF 3, which are still supported.
4741 Support for the HP aCC compiler on HP-UX/PA-RISC
4743 SOM-encapsulated symbolic debugging information, automatic
4744 invocation of pxdb, and the aCC custom C++ ABI. This does not
4745 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4746 with aCC can still be debugged on an assembly level.
4748 MIPS ".pdr" sections
4750 A MIPS-specific format used to describe stack frame layout
4751 in debugging information.
4755 GDB could work with an older version of Guile to debug
4756 the interpreter and Scheme programs running in it.
4758 set mips stack-arg-size
4759 set mips saved-gpreg-size
4761 Use "set mips abi" to control parameter passing for MIPS.
4763 *** Changes in GDB 6.6
4768 Cell Broadband Engine SPU spu-elf
4770 * GDB can now be configured as a cross-debugger targeting native Windows
4771 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4772 running on a Windows system over TCP/IP to debug Windows programs.
4774 * The GDB remote stub, gdbserver, has been updated to support Windows and
4775 Cygwin debugging. Both single-threaded and multi-threaded programs are
4778 * The "set trust-readonly-sections" command works again. This command was
4779 broken in GDB 6.3, 6.4, and 6.5.
4781 * The "load" command now supports writing to flash memory, if the remote
4782 stub provides the required support.
4784 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4785 longer requires symbolic debug information (e.g. DWARF-2).
4790 unset substitute-path
4791 show substitute-path
4792 Manage a list of substitution rules that GDB uses to rewrite the name
4793 of the directories where the sources are located. This can be useful
4794 for instance when the sources were moved to a different location
4795 between compilation and debugging.
4799 Print each CLI command as it is executed. Each command is prefixed with
4800 a number of `+' symbols representing the nesting depth.
4801 The source command now has a `-v' option to enable the same feature.
4805 The ARM Demon monitor support (RDP protocol, "target rdp").
4807 Kernel Object Display, an embedded debugging feature which only worked with
4808 an obsolete version of Cisco IOS.
4810 The 'set download-write-size' and 'show download-write-size' commands.
4812 * New remote packets
4815 Tell a stub about GDB client features, and request remote target features.
4816 The first feature implemented is PacketSize, which allows the target to
4817 specify the size of packets it can handle - to minimize the number of
4818 packets required and improve performance when connected to a remote
4822 Fetch an OS auxilliary vector from the remote stub. This packet is a
4823 more efficient replacement for qPart:auxv:read.
4825 qXfer:memory-map:read:
4826 Fetch a memory map from the remote stub, including information about
4827 RAM, ROM, and flash memory devices.
4832 Erase and program a flash memory device.
4834 * Removed remote packets
4837 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4838 used it, and only gdbserver implemented it.
4840 *** Changes in GDB 6.5
4844 Renesas M32C/M16C m32c-elf
4846 Morpho Technologies ms1 ms1-elf
4850 init-if-undefined Initialize a convenience variable, but
4851 only if it doesn't already have a value.
4853 The following commands are presently only implemented for native GNU/Linux:
4855 checkpoint Save a snapshot of the program state.
4857 restart <n> Return the program state to a
4858 previously saved state.
4860 info checkpoints List currently saved checkpoints.
4862 delete-checkpoint <n> Delete a previously saved checkpoint.
4864 set|show detach-on-fork Tell gdb whether to detach from a newly
4865 forked process, or to keep debugging it.
4867 info forks List forks of the user program that
4868 are available to be debugged.
4870 fork <n> Switch to debugging one of several
4871 forks of the user program that are
4872 available to be debugged.
4874 delete-fork <n> Delete a fork from the list of forks
4875 that are available to be debugged (and
4876 kill the forked process).
4878 detach-fork <n> Delete a fork from the list of forks
4879 that are available to be debugged (and
4880 allow the process to continue).
4884 Morpho Technologies ms2 ms1-elf
4886 * Improved Windows host support
4888 GDB now builds as a cross debugger hosted on i686-mingw32, including
4889 native console support, and remote communications using either
4890 network sockets or serial ports.
4892 * Improved Modula-2 language support
4894 GDB can now print most types in the Modula-2 syntax. This includes:
4895 basic types, set types, record types, enumerated types, range types,
4896 pointer types and ARRAY types. Procedure var parameters are correctly
4897 printed and hexadecimal addresses and character constants are also
4898 written in the Modula-2 syntax. Best results can be obtained by using
4899 GNU Modula-2 together with the -gdwarf-2 command line option.
4903 The ARM rdi-share module.
4905 The Netware NLM debug server.
4907 *** Changes in GDB 6.4
4909 * New native configurations
4911 OpenBSD/arm arm*-*-openbsd*
4912 OpenBSD/mips64 mips64-*-openbsd*
4916 Morpho Technologies ms1 ms1-elf
4918 * New command line options
4920 --batch-silent As for --batch, but totally silent.
4921 --return-child-result The debugger will exist with the same value
4922 the child (debugged) program exited with.
4923 --eval-command COMMAND, -ex COMMAND
4924 Execute a single GDB CLI command. This may be
4925 specified multiple times and in conjunction
4926 with the --command (-x) option.
4928 * Deprecated commands removed
4930 The following commands, that were deprecated in 2000, have been
4934 set|show arm disassembly-flavor set|show arm disassembler
4935 othernames set arm disassembler
4936 set|show remotedebug set|show debug remote
4937 set|show archdebug set|show debug arch
4938 set|show eventdebug set|show debug event
4941 * New BSD user-level threads support
4943 It is now possible to debug programs using the user-level threads
4944 library on OpenBSD and FreeBSD. Currently supported (target)
4947 FreeBSD/amd64 x86_64-*-freebsd*
4948 FreeBSD/i386 i386-*-freebsd*
4949 OpenBSD/i386 i386-*-openbsd*
4951 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4952 are not yet supported.
4954 * New support for Matsushita MN10300 w/sim added
4955 (Work in progress). mn10300-elf.
4957 * REMOVED configurations and files
4959 VxWorks and the XDR protocol *-*-vxworks
4960 Motorola MCORE mcore-*-*
4961 National Semiconductor NS32000 ns32k-*-*
4963 * New "set print array-indexes" command
4965 After turning this setting "on", GDB prints the index of each element
4966 when displaying arrays. The default is "off" to preserve the previous
4969 * VAX floating point support
4971 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4973 * User-defined command support
4975 In addition to using $arg0..$arg9 for argument passing, it is now possible
4976 to use $argc to determine now many arguments have been passed. See the
4977 section on user-defined commands in the user manual for more information.
4979 *** Changes in GDB 6.3:
4981 * New command line option
4983 GDB now accepts -l followed by a number to set the timeout for remote
4986 * GDB works with GCC -feliminate-dwarf2-dups
4988 GDB now supports a more compact representation of DWARF-2 debug
4989 information using DW_FORM_ref_addr references. These are produced
4990 by GCC with the option -feliminate-dwarf2-dups and also by some
4991 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4992 to use -feliminate-dwarf2-dups.
4994 * Internationalization
4996 When supported by the host system, GDB will be built with
4997 internationalization (libintl). The task of marking up the sources is
4998 continued, we're looking forward to our first translation.
5002 Initial support for debugging programs compiled with the GNAT
5003 implementation of the Ada programming language has been integrated
5004 into GDB. In this release, support is limited to expression evaluation.
5006 * New native configurations
5008 GNU/Linux/m32r m32r-*-linux-gnu
5012 GDB's remote protocol now includes support for the 'p' packet. This
5013 packet is used to fetch individual registers from a remote inferior.
5015 * END-OF-LIFE registers[] compatibility module
5017 GDB's internal register infrastructure has been completely rewritten.
5018 The new infrastructure making possible the implementation of key new
5019 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
5022 GDB 6.3 will be the last release to include the the registers[]
5023 compatibility module that allowed out-of-date configurations to
5024 continue to work. This change directly impacts the following
5034 powerpc bdm protocol
5036 Unless there is activity to revive these configurations, they will be
5037 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
5039 * OBSOLETE configurations and files
5041 Configurations that have been declared obsolete in this release have
5042 been commented out. Unless there is activity to revive these
5043 configurations, the next release of GDB will have their sources
5044 permanently REMOVED.
5053 *** Changes in GDB 6.2.1:
5055 * MIPS `break main; run' gave an heuristic-fence-post warning
5057 When attempting to run even a simple program, a warning about
5058 heuristic-fence-post being hit would be reported. This problem has
5061 * MIPS IRIX 'long double' crashed GDB
5063 When examining a long double variable, GDB would get a segmentation
5064 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
5065 IRIX long double values).
5069 A bug in the VAX stack code was causing problems with the "next"
5070 command. This problem has been fixed.
5072 *** Changes in GDB 6.2:
5074 * Fix for ``many threads''
5076 On GNU/Linux systems that use the NPTL threads library, a program
5077 rapidly creating and deleting threads would confuse GDB leading to the
5080 ptrace: No such process.
5081 thread_db_get_info: cannot get thread info: generic error
5083 This problem has been fixed.
5085 * "-async" and "-noasync" options removed.
5087 Support for the broken "-noasync" option has been removed (it caused
5090 * New ``start'' command.
5092 This command runs the program until the begining of the main procedure.
5094 * New BSD Kernel Data Access Library (libkvm) interface
5096 Using ``target kvm'' it is now possible to debug kernel core dumps and
5097 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
5098 platforms. Currently supported (native-only) configurations are:
5100 FreeBSD/amd64 x86_64-*-freebsd*
5101 FreeBSD/i386 i?86-*-freebsd*
5102 NetBSD/i386 i?86-*-netbsd*
5103 NetBSD/m68k m68*-*-netbsd*
5104 NetBSD/sparc sparc-*-netbsd*
5105 OpenBSD/amd64 x86_64-*-openbsd*
5106 OpenBSD/i386 i?86-*-openbsd*
5107 OpenBSD/m68k m68*-openbsd*
5108 OpenBSD/sparc sparc-*-openbsd*
5110 * Signal trampoline code overhauled
5112 Many generic problems with GDB's signal handling code have been fixed.
5113 These include: backtraces through non-contiguous stacks; recognition
5114 of sa_sigaction signal trampolines; backtrace from a NULL pointer
5115 call; backtrace through a signal trampoline; step into and out of
5116 signal handlers; and single-stepping in the signal trampoline.
5118 Please note that kernel bugs are a limiting factor here. These
5119 features have been shown to work on an s390 GNU/Linux system that
5120 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
5122 * Cygwin support for DWARF 2 added.
5124 * New native configurations
5126 GNU/Linux/hppa hppa*-*-linux*
5127 OpenBSD/hppa hppa*-*-openbsd*
5128 OpenBSD/m68k m68*-*-openbsd*
5129 OpenBSD/m88k m88*-*-openbsd*
5130 OpenBSD/powerpc powerpc-*-openbsd*
5131 NetBSD/vax vax-*-netbsd*
5132 OpenBSD/vax vax-*-openbsd*
5134 * END-OF-LIFE frame compatibility module
5136 GDB's internal frame infrastructure has been completely rewritten.
5137 The new infrastructure making it possible to support key new features
5138 including DWARF 2 Call Frame Information. To aid in the task of
5139 migrating old configurations to this new infrastructure, a
5140 compatibility module, that allowed old configurations to continue to
5141 work, was also included.
5143 GDB 6.2 will be the last release to include this frame compatibility
5144 module. This change directly impacts the following configurations:
5154 Unless there is activity to revive these configurations, they will be
5155 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
5157 * REMOVED configurations and files
5159 Sun 3, running SunOS 3 m68*-*-sunos3*
5160 Sun 3, running SunOS 4 m68*-*-sunos4*
5161 Sun 2, running SunOS 3 m68000-*-sunos3*
5162 Sun 2, running SunOS 4 m68000-*-sunos4*
5163 Motorola 680x0 running LynxOS m68*-*-lynxos*
5164 AT&T 3b1/Unix pc m68*-att-*
5165 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5166 decstation mips-dec-* mips-little-*
5167 riscos mips-*-riscos* mips-*-sysv*
5168 sonymips mips-sony-*
5169 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5171 *** Changes in GDB 6.1.1:
5173 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
5175 The TUI (Text-mode User Interface) is now built as part of a default
5176 GDB configuration. It is enabled by either selecting the TUI with the
5177 command line option "-i=tui" or by running the separate "gdbtui"
5178 program. For more information on the TUI, see the manual "Debugging
5181 * Pending breakpoint support (also included in GDB 6.1)
5183 Support has been added to allow you to specify breakpoints in shared
5184 libraries that have not yet been loaded. If a breakpoint location
5185 cannot be found, and the "breakpoint pending" option is set to auto,
5186 GDB queries you if you wish to make the breakpoint pending on a future
5187 shared-library load. If and when GDB resolves the breakpoint symbol,
5188 the pending breakpoint is removed as one or more regular breakpoints
5191 Pending breakpoints are very useful for GCJ Java debugging.
5193 * Fixed ISO-C build problems
5195 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
5196 non ISO-C code that stopped them being built using a more strict ISO-C
5197 compiler (e.g., IBM's C compiler).
5199 * Fixed build problem on IRIX 5
5201 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
5202 wasn't able to compile compile on an IRIX 5 system.
5204 * Added execute permission to gdb/gdbserver/configure
5206 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
5207 permission. This bug would cause configure to fail on a number of
5208 systems (Solaris, IRIX). Ref: server/519.
5210 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
5212 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
5213 has been updated to use constant array sizes.
5215 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
5217 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
5218 its generated DWARF Call Frame Info. This encoding was causing GDB to
5219 panic, that panic has been fixed. Ref: gdb/1628.
5221 * Fixed a problem when examining parameters in shared library code.
5223 When examining parameters in optimized shared library code generated
5224 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
5225 not available''. GDB now correctly displays the variable's value.
5227 *** Changes in GDB 6.1:
5229 * Removed --with-mmalloc
5231 Support for the mmalloc memory manager has been removed, as it
5232 conflicted with the internal gdb byte cache.
5234 * Changes in AMD64 configurations
5236 The AMD64 target now includes the %cs and %ss registers. As a result
5237 the AMD64 remote protocol has changed; this affects the floating-point
5238 and SSE registers. If you rely on those registers for your debugging,
5239 you should upgrade gdbserver on the remote side.
5241 * Revised SPARC target
5243 The SPARC target has been completely revised, incorporating the
5244 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
5245 support for LynxOS and SunOS 4 has been dropped. Calling functions
5246 from within GDB on operating systems with a non-executable stack
5247 (Solaris, OpenBSD) now works.
5251 GDB has a new C++ demangler which does a better job on the mangled
5252 names generated by current versions of g++. It also runs faster, so
5253 with this and other changes gdb should now start faster on large C++
5256 * DWARF 2 Location Expressions
5258 GDB support for location expressions has been extended to support function
5259 arguments and frame bases. Older versions of GDB could crash when they
5262 * C++ nested types and namespaces
5264 GDB's support for nested types and namespaces in C++ has been
5265 improved, especially if you use the DWARF 2 debugging format. (This
5266 is the default for recent versions of GCC on most platforms.)
5267 Specifically, if you have a class "Inner" defined within a class or
5268 namespace "Outer", then GDB realizes that the class's name is
5269 "Outer::Inner", not simply "Inner". This should greatly reduce the
5270 frequency of complaints about not finding RTTI symbols. In addition,
5271 if you are stopped at inside of a function defined within a namespace,
5272 GDB modifies its name lookup accordingly.
5274 * New native configurations
5276 NetBSD/amd64 x86_64-*-netbsd*
5277 OpenBSD/amd64 x86_64-*-openbsd*
5278 OpenBSD/alpha alpha*-*-openbsd*
5279 OpenBSD/sparc sparc-*-openbsd*
5280 OpenBSD/sparc64 sparc64-*-openbsd*
5282 * New debugging protocols
5284 M32R with SDI protocol m32r-*-elf*
5286 * "set prompt-escape-char" command deleted.
5288 The command "set prompt-escape-char" has been deleted. This command,
5289 and its very obscure effet on GDB's prompt, was never documented,
5290 tested, nor mentioned in the NEWS file.
5292 * OBSOLETE configurations and files
5294 Configurations that have been declared obsolete in this release have
5295 been commented out. Unless there is activity to revive these
5296 configurations, the next release of GDB will have their sources
5297 permanently REMOVED.
5299 Sun 3, running SunOS 3 m68*-*-sunos3*
5300 Sun 3, running SunOS 4 m68*-*-sunos4*
5301 Sun 2, running SunOS 3 m68000-*-sunos3*
5302 Sun 2, running SunOS 4 m68000-*-sunos4*
5303 Motorola 680x0 running LynxOS m68*-*-lynxos*
5304 AT&T 3b1/Unix pc m68*-att-*
5305 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5306 decstation mips-dec-* mips-little-*
5307 riscos mips-*-riscos* mips-*-sysv*
5308 sonymips mips-sony-*
5309 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5311 * REMOVED configurations and files
5313 SGI Irix-4.x mips-sgi-irix4 or iris4
5314 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5315 Z8000 simulator z8k-zilog-none or z8ksim
5316 Matsushita MN10200 w/simulator mn10200-*-*
5317 H8/500 simulator h8500-hitachi-hms or h8500hms
5318 HP/PA running BSD hppa*-*-bsd*
5319 HP/PA running OSF/1 hppa*-*-osf*
5320 HP/PA Pro target hppa*-*-pro*
5321 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5322 386BSD i[3456]86-*-bsd*
5323 Sequent family i[3456]86-sequent-sysv4*
5324 i[3456]86-sequent-sysv*
5325 i[3456]86-sequent-bsd*
5326 SPARC running LynxOS sparc-*-lynxos*
5327 SPARC running SunOS 4 sparc-*-sunos4*
5328 Tsqware Sparclet sparclet-*-*
5329 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5331 *** Changes in GDB 6.0:
5335 Support for debugging the Objective-C programming language has been
5336 integrated into GDB.
5338 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5340 DWARF 2's Call Frame Information makes available compiler generated
5341 information that more exactly describes the program's run-time stack.
5342 By using this information, GDB is able to provide more robust stack
5345 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5346 have been updated to use a new backtrace mechanism which includes
5347 DWARF 2 CFI support.
5351 GDB's remote protocol has been extended to include support for hosted
5352 file I/O (where the remote target uses GDB's file system). See GDB's
5353 remote protocol documentation for details.
5355 * All targets using the new architecture framework.
5357 All of GDB's targets have been updated to use the new internal
5358 architecture framework. The way is now open for future GDB releases
5359 to include cross-architecture native debugging support (i386 on amd64,
5362 * GNU/Linux's Thread Local Storage (TLS)
5364 GDB now includes support for for the GNU/Linux implementation of
5365 per-thread variables.
5367 * GNU/Linux's Native POSIX Thread Library (NPTL)
5369 GDB's thread code has been updated to work with either the new
5370 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5372 * Separate debug info.
5374 GDB, in conjunction with BINUTILS, now supports a mechanism for
5375 automatically loading debug information from a separate file. Instead
5376 of shipping full debug and non-debug versions of system libraries,
5377 system integrators can now instead ship just the stripped libraries
5378 and optional debug files.
5380 * DWARF 2 Location Expressions
5382 DWARF 2 Location Expressions allow the compiler to more completely
5383 describe the location of variables (even in optimized code) to the
5386 GDB now includes preliminary support for location expressions (support
5387 for DW_OP_piece is still missing).
5391 A number of long standing bugs that caused GDB to die while starting a
5392 Java application have been fixed. GDB's Java support is now
5393 considered "useable".
5395 * GNU/Linux support for fork, vfork, and exec.
5397 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5398 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5401 * GDB supports logging output to a file
5403 There are two new commands, "set logging" and "show logging", which can be
5404 used to capture GDB's output to a file.
5406 * The meaning of "detach" has changed for gdbserver
5408 The "detach" command will now resume the application, as documented. To
5409 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5412 * d10v, m68hc11 `regs' command deprecated
5414 The `info registers' command has been updated so that it displays the
5415 registers using a format identical to the old `regs' command.
5419 A new command, "maint set profile on/off", has been added. This command can
5420 be used to enable or disable profiling while running GDB, to profile a
5421 session or a set of commands. In addition there is a new configure switch,
5422 "--enable-profiling", which will cause GDB to be compiled with profiling
5423 data, for more informative profiling results.
5425 * Default MI syntax changed to "mi2".
5427 The default MI (machine interface) syntax, enabled by the command line
5428 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5429 "mi1", can be enabled by specifying the option "-i=mi1".
5431 Support for the original "mi0" syntax (included in GDB 5.0) has been
5434 Fix for gdb/192: removed extraneous space when displaying frame level.
5435 Fix for gdb/672: update changelist is now output in mi list format.
5436 Fix for gdb/702: a -var-assign that updates the value now shows up
5437 in a subsequent -var-update.
5439 * New native configurations.
5441 FreeBSD/amd64 x86_64-*-freebsd*
5443 * Multi-arched targets.
5445 HP/PA HPUX11 hppa*-*-hpux*
5446 Renesas M32R/D w/simulator m32r-*-elf*
5448 * OBSOLETE configurations and files
5450 Configurations that have been declared obsolete in this release have
5451 been commented out. Unless there is activity to revive these
5452 configurations, the next release of GDB will have their sources
5453 permanently REMOVED.
5455 Z8000 simulator z8k-zilog-none or z8ksim
5456 Matsushita MN10200 w/simulator mn10200-*-*
5457 H8/500 simulator h8500-hitachi-hms or h8500hms
5458 HP/PA running BSD hppa*-*-bsd*
5459 HP/PA running OSF/1 hppa*-*-osf*
5460 HP/PA Pro target hppa*-*-pro*
5461 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5462 Sequent family i[3456]86-sequent-sysv4*
5463 i[3456]86-sequent-sysv*
5464 i[3456]86-sequent-bsd*
5465 Tsqware Sparclet sparclet-*-*
5466 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5468 * REMOVED configurations and files
5471 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5472 IBM AIX PS/2 i[3456]86-*-aix
5473 i386 running Mach 3.0 i[3456]86-*-mach3*
5474 i386 running Mach i[3456]86-*-mach*
5475 i386 running OSF/1 i[3456]86-*osf1mk*
5476 HP/Apollo 68k Family m68*-apollo*-sysv*,
5478 m68*-hp-bsd*, m68*-hp-hpux*
5479 Argonaut Risc Chip (ARC) arc-*-*
5480 Mitsubishi D30V d30v-*-*
5481 Fujitsu FR30 fr30-*-elf*
5482 OS/9000 i[34]86-*-os9k
5483 I960 with MON960 i960-*-coff
5485 * MIPS $fp behavior changed
5487 The convenience variable $fp, for the MIPS, now consistently returns
5488 the address of the current frame's base. Previously, depending on the
5489 context, $fp could refer to either $sp or the current frame's base
5490 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5491 The GNU Source-Level Debugger''.
5493 *** Changes in GDB 5.3:
5495 * GNU/Linux shared library multi-threaded performance improved.
5497 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5498 `/proc', in preference to `ptrace' for memory reads. This may result
5499 in an improvement in the start-up time of multi-threaded, shared
5500 library applications when run under GDB. One GDB user writes: ``loads
5501 shared libs like mad''.
5503 * ``gdbserver'' now supports multi-threaded applications on some targets
5505 Support for debugging multi-threaded applications which use
5506 the GNU/Linux LinuxThreads package has been added for
5507 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5508 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5510 * GDB now supports C/C++ preprocessor macros.
5512 GDB now expands preprocessor macro invocations in C/C++ expressions,
5513 and provides various commands for showing macro definitions and how
5516 The new command `macro expand EXPRESSION' expands any macro
5517 invocations in expression, and shows the result.
5519 The new command `show macro MACRO-NAME' shows the definition of the
5520 macro named MACRO-NAME, and where it was defined.
5522 Most compilers don't include information about macros in the debugging
5523 information by default. In GCC 3.1, for example, you need to compile
5524 your program with the options `-gdwarf-2 -g3'. If the macro
5525 information is present in the executable, GDB will read it.
5527 * Multi-arched targets.
5529 DEC Alpha (partial) alpha*-*-*
5530 DEC VAX (partial) vax-*-*
5532 National Semiconductor NS32000 (partial) ns32k-*-*
5533 Motorola 68000 (partial) m68k-*-*
5534 Motorola MCORE mcore-*-*
5538 Fujitsu FRV architecture added by Red Hat frv*-*-*
5541 * New native configurations
5543 Alpha NetBSD alpha*-*-netbsd*
5544 SH NetBSD sh*-*-netbsdelf*
5545 MIPS NetBSD mips*-*-netbsd*
5546 UltraSPARC NetBSD sparc64-*-netbsd*
5548 * OBSOLETE configurations and files
5550 Configurations that have been declared obsolete in this release have
5551 been commented out. Unless there is activity to revive these
5552 configurations, the next release of GDB will have their sources
5553 permanently REMOVED.
5555 Mitsubishi D30V d30v-*-*
5556 OS/9000 i[34]86-*-os9k
5557 IBM AIX PS/2 i[3456]86-*-aix
5558 Fujitsu FR30 fr30-*-elf*
5559 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5560 Argonaut Risc Chip (ARC) arc-*-*
5561 i386 running Mach 3.0 i[3456]86-*-mach3*
5562 i386 running Mach i[3456]86-*-mach*
5563 i386 running OSF/1 i[3456]86-*osf1mk*
5564 HP/Apollo 68k Family m68*-apollo*-sysv*,
5566 m68*-hp-bsd*, m68*-hp-hpux*
5567 I960 with MON960 i960-*-coff
5569 * OBSOLETE languages
5571 CHILL, a Pascal like language used by telecommunications companies.
5573 * REMOVED configurations and files
5575 AMD 29k family via UDI a29k-amd-udi, udi29k
5576 A29K VxWorks a29k-*-vxworks
5577 AMD 29000 embedded, using EBMON a29k-none-none
5578 AMD 29000 embedded with COFF a29k-none-coff
5579 AMD 29000 embedded with a.out a29k-none-aout
5581 testsuite/gdb.hp/gdb.threads-hp/ directory
5583 * New command "set max-user-call-depth <nnn>"
5585 This command allows the user to limit the call depth of user-defined
5586 commands. The default is 1024.
5588 * Changes in FreeBSD/i386 native debugging.
5590 Support for the "generate-core-file" has been added.
5592 * New commands "dump", "append", and "restore".
5594 These commands allow data to be copied from target memory
5595 to a bfd-format or binary file (dump and append), and back
5596 from a file into memory (restore).
5598 * Improved "next/step" support on multi-processor Alpha Tru64.
5600 The previous single-step mechanism could cause unpredictable problems,
5601 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5602 of a software single-step mechanism prevents this.
5604 *** Changes in GDB 5.2.1:
5612 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5613 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5614 Fix, by Joel Brobecker imported from mainline.
5616 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5617 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5618 Fix, by Fred Fish, imported from mainline.
5620 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5621 Surprisingly enough, it works now.
5622 By Michal Ludvig, imported from mainline.
5624 i386 hardware watchpoint support:
5625 avoid misses on second run for some targets.
5626 By Pierre Muller, imported from mainline.
5628 *** Changes in GDB 5.2:
5630 * New command "set trust-readonly-sections on[off]".
5632 This command is a hint that tells gdb that read-only sections
5633 really are read-only (ie. that their contents will not change).
5634 In this mode, gdb will go to the object file rather than the
5635 target to read memory from read-only sections (such as ".text").
5636 This can be a significant performance improvement on some
5637 (notably embedded) targets.
5639 * New command "generate-core-file" (or "gcore").
5641 This new gdb command allows the user to drop a core file of the child
5642 process state at any time. So far it's been implemented only for
5643 GNU/Linux and Solaris, but should be relatively easily ported to other
5644 hosts. Argument is core file name (defaults to core.<pid>).
5646 * New command line option
5648 GDB now accepts --pid or -p followed by a process id.
5650 * Change in command line behavior -- corefiles vs. process ids.
5652 There is a subtle behavior in the way in which GDB handles
5653 command line arguments. The first non-flag argument is always
5654 a program to debug, but the second non-flag argument may either
5655 be a corefile or a process id. Previously, GDB would attempt to
5656 open the second argument as a corefile, and if that failed, would
5657 issue a superfluous error message and then attempt to attach it as
5658 a process. Now, if the second argument begins with a non-digit,
5659 it will be treated as a corefile. If it begins with a digit,
5660 GDB will attempt to attach it as a process, and if no such process
5661 is found, will then attempt to open it as a corefile.
5663 * Changes in ARM configurations.
5665 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5666 configuration is fully multi-arch.
5668 * New native configurations
5670 ARM NetBSD arm*-*-netbsd*
5671 x86 OpenBSD i[3456]86-*-openbsd*
5672 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5673 Sparc64 running FreeBSD sparc64-*-freebsd*
5677 Sanyo XStormy16 xstormy16-elf
5679 * OBSOLETE configurations and files
5681 Configurations that have been declared obsolete in this release have
5682 been commented out. Unless there is activity to revive these
5683 configurations, the next release of GDB will have their sources
5684 permanently REMOVED.
5686 AMD 29k family via UDI a29k-amd-udi, udi29k
5687 A29K VxWorks a29k-*-vxworks
5688 AMD 29000 embedded, using EBMON a29k-none-none
5689 AMD 29000 embedded with COFF a29k-none-coff
5690 AMD 29000 embedded with a.out a29k-none-aout
5692 testsuite/gdb.hp/gdb.threads-hp/ directory
5694 * REMOVED configurations and files
5696 TI TMS320C80 tic80-*-*
5698 PowerPC Solaris powerpcle-*-solaris*
5699 PowerPC Windows NT powerpcle-*-cygwin32
5700 PowerPC Netware powerpc-*-netware*
5701 Harris/CXUX m88k m88*-harris-cxux*
5702 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5703 ns32k-utek-sysv* ns32k-utek-*
5704 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5705 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5706 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5707 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5708 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5710 * Changes to command line processing
5712 The new `--args' feature can be used to specify command-line arguments
5713 for the inferior from gdb's command line.
5715 * Changes to key bindings
5717 There is a new `operate-and-get-next' function bound to `C-o'.
5719 *** Changes in GDB 5.1.1
5721 Fix compile problem on DJGPP.
5723 Fix a problem with floating-point registers on the i386 being
5726 Fix to stop GDB crashing on .debug_str debug info.
5728 Numerous documentation fixes.
5730 Numerous testsuite fixes.
5732 *** Changes in GDB 5.1:
5734 * New native configurations
5736 Alpha FreeBSD alpha*-*-freebsd*
5737 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5738 MIPS GNU/Linux mips*-*-linux*
5739 MIPS SGI Irix 6.x mips*-sgi-irix6*
5740 ia64 AIX ia64-*-aix*
5741 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5745 Motorola 68HC11 and 68HC12 m68hc11-elf
5747 UltraSparc running GNU/Linux sparc64-*-linux*
5749 * OBSOLETE configurations and files
5751 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5752 Harris/CXUX m88k m88*-harris-cxux*
5753 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5754 ns32k-utek-sysv* ns32k-utek-*
5755 TI TMS320C80 tic80-*-*
5757 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5758 PowerPC Solaris powerpcle-*-solaris*
5759 PowerPC Windows NT powerpcle-*-cygwin32
5760 PowerPC Netware powerpc-*-netware*
5761 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5762 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5763 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5764 Apple Macintosh (MPW) host N/A
5766 stuff.c (Program to stuff files into a specially prepared space in kdb)
5767 kdb-start.c (Main loop for the standalone kernel debugger)
5769 Configurations that have been declared obsolete in this release have
5770 been commented out. Unless there is activity to revive these
5771 configurations, the next release of GDB will have their sources
5772 permanently REMOVED.
5774 * REMOVED configurations and files
5776 Altos 3068 m68*-altos-*
5777 Convex c1-*-*, c2-*-*
5779 ARM RISCix arm-*-* (as host)
5783 * GDB has been converted to ISO C.
5785 GDB's source code has been converted to ISO C. In particular, the
5786 sources are fully protoized, and rely on standard headers being
5791 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5793 * The MI enabled by default.
5795 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5796 revised and enabled by default. Packages which use GDB as a debugging
5797 engine behind a UI or another front end are encouraged to switch to
5798 using the GDB/MI interface, instead of the old annotations interface
5799 which is now deprecated.
5801 * Support for debugging Pascal programs.
5803 GDB now includes support for debugging Pascal programs. The following
5804 main features are supported:
5806 - Pascal-specific data types such as sets;
5808 - automatic recognition of Pascal sources based on file-name
5811 - Pascal-style display of data types, variables, and functions;
5813 - a Pascal expression parser.
5815 However, some important features are not yet supported.
5817 - Pascal string operations are not supported at all;
5819 - there are some problems with boolean types;
5821 - Pascal type hexadecimal constants are not supported
5822 because they conflict with the internal variables format;
5824 - support for Pascal objects and classes is not full yet;
5826 - unlike Pascal, GDB is case-sensitive for symbol names.
5828 * Changes in completion.
5830 Commands such as `shell', `run' and `set args', which pass arguments
5831 to inferior programs, now complete on file names, similar to what
5832 users expect at the shell prompt.
5834 Commands which accept locations, such as `disassemble', `print',
5835 `breakpoint', `until', etc. now complete on filenames as well as
5836 program symbols. Thus, if you type "break foob TAB", and the source
5837 files linked into the programs include `foobar.c', that file name will
5838 be one of the candidates for completion. However, file names are not
5839 considered for completion after you typed a colon that delimits a file
5840 name from a name of a function in that file, as in "break foo.c:bar".
5842 `set demangle-style' completes on available demangling styles.
5844 * New platform-independent commands:
5846 It is now possible to define a post-hook for a command as well as a
5847 hook that runs before the command. For more details, see the
5848 documentation of `hookpost' in the GDB manual.
5850 * Changes in GNU/Linux native debugging.
5852 Support for debugging multi-threaded programs has been completely
5853 revised for all platforms except m68k and sparc. You can now debug as
5854 many threads as your system allows you to have.
5856 Attach/detach is supported for multi-threaded programs.
5858 Support for SSE registers was added for x86. This doesn't work for
5859 multi-threaded programs though.
5861 * Changes in MIPS configurations.
5863 Multi-arch support is enabled for all MIPS configurations.
5865 GDB can now be built as native debugger on SGI Irix 6.x systems for
5866 debugging n32 executables. (Debugging 64-bit executables is not yet
5869 * Unified support for hardware watchpoints in all x86 configurations.
5871 Most (if not all) native x86 configurations support hardware-assisted
5872 breakpoints and watchpoints in a unified manner. This support
5873 implements debug register sharing between watchpoints, which allows to
5874 put a virtually infinite number of watchpoints on the same address,
5875 and also supports watching regions up to 16 bytes with several debug
5878 The new maintenance command `maintenance show-debug-regs' toggles
5879 debugging print-outs in functions that insert, remove, and test
5880 watchpoints and hardware breakpoints.
5882 * Changes in the DJGPP native configuration.
5884 New command ``info dos sysinfo'' displays assorted information about
5885 the CPU, OS, memory, and DPMI server.
5887 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5888 display information about segment descriptors stored in GDT, LDT, and
5891 New commands ``info dos pde'' and ``info dos pte'' display entries
5892 from Page Directory and Page Tables (for now works with CWSDPMI only).
5893 New command ``info dos address-pte'' displays the Page Table entry for
5894 a given linear address.
5896 GDB can now pass command lines longer than 126 characters to the
5897 program being debugged (requires an update to the libdbg.a library
5898 which is part of the DJGPP development kit).
5900 DWARF2 debug info is now supported.
5902 It is now possible to `step' and `next' through calls to `longjmp'.
5904 * Changes in documentation.
5906 All GDB documentation was converted to GFDL, the GNU Free
5907 Documentation License.
5909 Tracepoints-related commands are now fully documented in the GDB
5912 TUI, the Text-mode User Interface, is now documented in the manual.
5914 Tracepoints-related commands are now fully documented in the GDB
5917 The "GDB Internals" manual now has an index. It also includes
5918 documentation of `ui_out' functions, GDB coding standards, x86
5919 hardware watchpoints, and memory region attributes.
5921 * GDB's version number moved to ``version.in''
5923 The Makefile variable VERSION has been replaced by the file
5924 ``version.in''. People creating GDB distributions should update the
5925 contents of this file.
5929 GUD support is now a standard part of the EMACS distribution.
5931 *** Changes in GDB 5.0:
5933 * Improved support for debugging FP programs on x86 targets
5935 Unified and much-improved support for debugging floating-point
5936 programs on all x86 targets. In particular, ``info float'' now
5937 displays the FP registers in the same format on all x86 targets, with
5938 greater level of detail.
5940 * Improvements and bugfixes in hardware-assisted watchpoints
5942 It is now possible to watch array elements, struct members, and
5943 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5944 on x86 targets no longer erroneously trigger when the address is
5947 * Improvements in the native DJGPP version of GDB
5949 The distribution now includes all the scripts and auxiliary files
5950 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5951 machines ``out of the box''.
5953 The DJGPP version can now debug programs that use signals. It is
5954 possible to catch signals that happened in the debuggee, deliver
5955 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5956 would kill the program being debugged.) Programs that hook hardware
5957 interrupts (keyboard, timer, etc.) can also be debugged.
5959 It is now possible to debug DJGPP programs that redirect their
5960 standard handles or switch them to raw (as opposed to cooked) mode, or
5961 even close them. The command ``run < foo > bar'' works as expected,
5962 and ``info terminal'' reports useful information about the debuggee's
5963 terminal, including raw/cooked mode, redirection, etc.
5965 The DJGPP version now uses termios functions for console I/O, which
5966 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5969 DOS-style file names with drive letters are now fully supported by
5972 It is now possible to debug DJGPP programs that switch their working
5973 directory. It is also possible to rerun the debuggee any number of
5974 times without restarting GDB; thus, you can use the same setup,
5975 breakpoints, etc. for many debugging sessions.
5977 * New native configurations
5979 ARM GNU/Linux arm*-*-linux*
5980 PowerPC GNU/Linux powerpc-*-linux*
5984 Motorola MCore mcore-*-*
5985 x86 VxWorks i[3456]86-*-vxworks*
5986 PowerPC VxWorks powerpc-*-vxworks*
5987 TI TMS320C80 tic80-*-*
5989 * OBSOLETE configurations
5991 Altos 3068 m68*-altos-*
5992 Convex c1-*-*, c2-*-*
5994 ARM RISCix arm-*-* (as host)
5997 Configurations that have been declared obsolete will be commented out,
5998 but the code will be left in place. If there is no activity to revive
5999 these configurations before the next release of GDB, the sources will
6000 be permanently REMOVED.
6002 * Gould support removed
6004 Support for the Gould PowerNode and NP1 has been removed.
6006 * New features for SVR4
6008 On SVR4 native platforms (such as Solaris), if you attach to a process
6009 without first loading a symbol file, GDB will now attempt to locate and
6010 load symbols from the running process's executable file.
6012 * Many C++ enhancements
6014 C++ support has been greatly improved. Overload resolution now works properly
6015 in almost all cases. RTTI support is on the way.
6017 * Remote targets can connect to a sub-program
6019 A popen(3) style serial-device has been added. This device starts a
6020 sub-process (such as a stand-alone simulator) and then communicates
6021 with that. The sub-program to run is specified using the syntax
6022 ``|<program> <args>'' vis:
6024 (gdb) set remotedebug 1
6025 (gdb) target extended-remote |mn10300-elf-sim program-args
6027 * MIPS 64 remote protocol
6029 A long standing bug in the mips64 remote protocol where by GDB
6030 expected certain 32 bit registers (ex SR) to be transfered as 32
6031 instead of 64 bits has been fixed.
6033 The command ``set remote-mips64-transfers-32bit-regs on'' has been
6034 added to provide backward compatibility with older versions of GDB.
6036 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
6038 The command ``set remotebinarydownload'' command has been replaced by
6039 ``set remote X-packet''. Other commands in ``set remote'' family
6040 include ``set remote P-packet''.
6042 * Breakpoint commands accept ranges.
6044 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
6045 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
6046 ``tracepoint passcount'' also accepts a range of tracepoints.
6048 * ``apropos'' command added.
6050 The ``apropos'' command searches through command names and
6051 documentation strings, printing out matches, making it much easier to
6052 try to find a command that does what you are looking for.
6056 A new machine oriented interface (MI) has been added to GDB. This
6057 interface is designed for debug environments running GDB as a separate
6058 process. This is part of the long term libGDB project. See the
6059 "GDB/MI" chapter of the GDB manual for further information. It can be
6060 enabled by configuring with:
6062 .../configure --enable-gdbmi
6064 *** Changes in GDB-4.18:
6066 * New native configurations
6068 HP-UX 10.20 hppa*-*-hpux10.20
6069 HP-UX 11.x hppa*-*-hpux11.0*
6070 M68K GNU/Linux m68*-*-linux*
6074 Fujitsu FR30 fr30-*-elf*
6075 Intel StrongARM strongarm-*-*
6076 Mitsubishi D30V d30v-*-*
6078 * OBSOLETE configurations
6080 Gould PowerNode, NP1 np1-*-*, pn-*-*
6082 Configurations that have been declared obsolete will be commented out,
6083 but the code will be left in place. If there is no activity to revive
6084 these configurations before the next release of GDB, the sources will
6085 be permanently REMOVED.
6089 As a compatibility experiment, GDB's source files buildsym.h and
6090 buildsym.c have been converted to pure standard C, no longer
6091 containing any K&R compatibility code. We believe that all systems in
6092 use today either come with a standard C compiler, or have a GCC port
6093 available. If this is not true, please report the affected
6094 configuration to bug-gdb@gnu.org immediately. See the README file for
6095 information about getting a standard C compiler if you don't have one
6100 GDB now uses readline 2.2.
6102 * set extension-language
6104 You can now control the mapping between filename extensions and source
6105 languages by using the `set extension-language' command. For instance,
6106 you can ask GDB to treat .c files as C++ by saying
6107 set extension-language .c c++
6108 The command `info extensions' lists all of the recognized extensions
6109 and their associated languages.
6111 * Setting processor type for PowerPC and RS/6000
6113 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
6114 you can use the `set processor' command to specify what variant of the
6115 PowerPC family you are debugging. The command
6119 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
6120 following PowerPC and RS6000 variants:
6122 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
6123 rs6000 IBM RS6000 ("POWER") architecture, user-level view
6125 403GC IBM PowerPC 403GC
6126 505 Motorola PowerPC 505
6127 860 Motorola PowerPC 860 or 850
6128 601 Motorola PowerPC 601
6129 602 Motorola PowerPC 602
6130 603 Motorola/IBM PowerPC 603 or 603e
6131 604 Motorola PowerPC 604 or 604e
6132 750 Motorola/IBM PowerPC 750 or 750
6134 At the moment, this command just tells GDB what to name the
6135 special-purpose processor registers. Since almost all the affected
6136 registers are inaccessible to user-level programs, this command is
6137 only useful for remote debugging in its present form.
6141 Thanks to a major code donation from Hewlett-Packard, GDB now has much
6142 more extensive support for HP-UX. Added features include shared
6143 library support, kernel threads and hardware watchpoints for 11.00,
6144 support for HP's ANSI C and C++ compilers, and a compatibility mode
6145 for xdb and dbx commands.
6149 HP's donation includes the new concept of catchpoints, which is a
6150 generalization of the old catch command. On HP-UX, it is now possible
6151 to catch exec, fork, and vfork, as well as library loading.
6153 This means that the existing catch command has changed; its first
6154 argument now specifies the type of catch to be set up. See the
6155 output of "help catch" for a list of catchpoint types.
6157 * Debugging across forks
6159 On HP-UX, you can choose which process to debug when a fork() happens
6164 HP has donated a curses-based terminal user interface (TUI). To get
6165 it, build with --enable-tui. Although this can be enabled for any
6166 configuration, at present it only works for native HP debugging.
6168 * GDB remote protocol additions
6170 A new protocol packet 'X' that writes binary data is now available.
6171 Default behavior is to try 'X', then drop back to 'M' if the stub
6172 fails to respond. The settable variable `remotebinarydownload'
6173 allows explicit control over the use of 'X'.
6175 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
6176 full 64-bit address. The command
6178 set remoteaddresssize 32
6180 can be used to revert to the old behaviour. For existing remote stubs
6181 the change should not be noticed, as the additional address information
6184 In order to assist in debugging stubs, you may use the maintenance
6185 command `packet' to send any text string to the stub. For instance,
6187 maint packet heythere
6189 sends the packet "$heythere#<checksum>". Note that it is very easy to
6190 disrupt a debugging session by sending the wrong packet at the wrong
6193 The compare-sections command allows you to compare section data on the
6194 target to what is in the executable file without uploading or
6195 downloading, by comparing CRC checksums.
6197 * Tracing can collect general expressions
6199 You may now collect general expressions at tracepoints. This requires
6200 further additions to the target-side stub; see tracepoint.c and
6201 doc/agentexpr.texi for further details.
6203 * mask-address variable for Mips
6205 For Mips targets, you may control the zeroing of the upper 32 bits of
6206 a 64-bit address by entering `set mask-address on'. This is mainly
6207 of interest to users of embedded R4xxx and R5xxx processors.
6209 * Higher serial baud rates
6211 GDB's serial code now allows you to specify baud rates 57600, 115200,
6212 230400, and 460800 baud. (Note that your host system may not be able
6213 to achieve all of these rates.)
6217 The i960 configuration now includes an initial implementation of a
6218 builtin simulator, contributed by Jim Wilson.
6221 *** Changes in GDB-4.17:
6223 * New native configurations
6225 Alpha GNU/Linux alpha*-*-linux*
6226 Unixware 2.x i[3456]86-unixware2*
6227 Irix 6.x mips*-sgi-irix6*
6228 PowerPC GNU/Linux powerpc-*-linux*
6229 PowerPC Solaris powerpcle-*-solaris*
6230 Sparc GNU/Linux sparc-*-linux*
6231 Motorola sysV68 R3V7.1 m68k-motorola-sysv
6235 Argonaut Risc Chip (ARC) arc-*-*
6236 Hitachi H8/300S h8300*-*-*
6237 Matsushita MN10200 w/simulator mn10200-*-*
6238 Matsushita MN10300 w/simulator mn10300-*-*
6239 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
6240 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
6241 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
6242 Mitsubishi D10V w/simulator d10v-*-*
6243 Mitsubishi M32R/D w/simulator m32r-*-elf*
6244 Tsqware Sparclet sparclet-*-*
6245 NEC V850 w/simulator v850-*-*
6247 * New debugging protocols
6249 ARM with RDI protocol arm*-*-*
6250 M68K with dBUG monitor m68*-*-{aout,coff,elf}
6251 DDB and LSI variants of PMON protocol mips*-*-*
6252 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
6253 PowerPC with SDS protocol powerpc{,le}-*-eabi
6254 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6258 All configurations can now understand and use the DWARF 2 debugging
6259 format. The choice is automatic, if the symbol file contains DWARF 2
6264 GDB now includes basic Java language support. This support is
6265 only useful with Java compilers that produce native machine code.
6267 * solib-absolute-prefix and solib-search-path
6269 For SunOS and SVR4 shared libraries, you may now set the prefix for
6270 loading absolute shared library symbol files, and the search path for
6271 locating non-absolute shared library symbol files.
6273 * Live range splitting
6275 GDB can now effectively debug code for which GCC has performed live
6276 range splitting as part of its optimization. See gdb/doc/LRS for
6277 more details on the expected format of the stabs information.
6281 GDB's support for the GNU Hurd, including thread debugging, has been
6282 updated to work with current versions of the Hurd.
6286 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6287 instruction set. ARM GDB automatically detects when Thumb
6288 instructions are in use, and adjusts disassembly and backtracing
6293 GDB's MIPS target configurations now handle the MIP16 16-bit
6298 GDB now includes support for overlays; if an executable has been
6299 linked such that multiple sections are based at the same address, GDB
6300 will decide which section to use for symbolic info. You can choose to
6301 control the decision manually, using overlay commands, or implement
6302 additional target-side support and use "overlay load-target" to bring
6303 in the overlay mapping. Do "help overlay" for more detail.
6307 The command "info symbol <address>" displays information about
6308 the symbol at the specified address.
6312 The standard remote protocol now includes an extension that allows
6313 asynchronous collection and display of trace data. This requires
6314 extensive support in the target-side debugging stub. Tracing mode
6315 includes a new interaction mode in GDB and new commands: see the
6316 file tracepoint.c for more details.
6320 Configurations for embedded MIPS now include a simulator contributed
6321 by Cygnus Solutions. The simulator supports the instruction sets
6322 of most MIPS variants.
6326 Sparc configurations may now include the ERC32 simulator contributed
6327 by the European Space Agency. The simulator is not built into
6328 Sparc targets by default; configure with --enable-sim to include it.
6332 For target configurations that may include multiple variants of a
6333 basic architecture (such as MIPS and SH), you may now set the
6334 architecture explicitly. "set arch" sets, "info arch" lists
6335 the possible architectures.
6337 *** Changes in GDB-4.16:
6339 * New native configurations
6341 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6342 M68K NetBSD m68k-*-netbsd*
6343 PowerPC AIX 4.x powerpc-*-aix*
6344 PowerPC MacOS powerpc-*-macos*
6345 PowerPC Windows NT powerpcle-*-cygwin32
6346 RS/6000 AIX 4.x rs6000-*-aix4*
6350 ARM with RDP protocol arm-*-*
6351 I960 with MON960 i960-*-coff
6352 MIPS VxWorks mips*-*-vxworks*
6353 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6354 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6356 Matra Sparclet sparclet-*-*
6360 The powerpc-eabi configuration now includes the PSIM simulator,
6361 contributed by Andrew Cagney, with assistance from Mike Meissner.
6362 PSIM is a very elaborate model of the PowerPC, including not only
6363 basic instruction set execution, but also details of execution unit
6364 performance and I/O hardware. See sim/ppc/README for more details.
6368 GDB now works with Solaris 2.5.
6370 * Windows 95/NT native
6372 GDB will now work as a native debugger on Windows 95 and Windows NT.
6373 To build it from source, you must use the "gnu-win32" environment,
6374 which uses a DLL to emulate enough of Unix to run the GNU tools.
6375 Further information, binaries, and sources are available at
6376 ftp.cygnus.com, under pub/gnu-win32.
6378 * dont-repeat command
6380 If a user-defined command includes the command `dont-repeat', then the
6381 command will not be repeated if the user just types return. This is
6382 useful if the command is time-consuming to run, so that accidental
6383 extra keystrokes don't run the same command many times.
6385 * Send break instead of ^C
6387 The standard remote protocol now includes an option to send a break
6388 rather than a ^C to the target in order to interrupt it. By default,
6389 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6391 * Remote protocol timeout
6393 The standard remote protocol includes a new variable `remotetimeout'
6394 that allows you to set the number of seconds before GDB gives up trying
6395 to read from the target. The default value is 2.
6397 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6399 By default GDB will automatically keep track of objects as they are
6400 loaded and unloaded by the dynamic linker. By using the command `set
6401 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6402 when shared library events occur, thus allowing you to set breakpoints
6403 in shared libraries which are explicitly loaded by the inferior.
6405 Note this feature does not work on hpux8. On hpux9 you must link
6406 /usr/lib/end.o into your program. This feature should work
6407 automatically on hpux10.
6409 * Irix 5.x hardware watchpoint support
6411 Irix 5 configurations now support the use of hardware watchpoints.
6413 * Mips protocol "SYN garbage limit"
6415 When debugging a Mips target using the `target mips' protocol, you
6416 may set the number of characters that GDB will ignore by setting
6417 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6418 every character. The default value is 1050.
6420 * Recording and replaying remote debug sessions
6422 If you set `remotelogfile' to the name of a file, gdb will write to it
6423 a recording of a remote debug session. This recording may then be
6424 replayed back to gdb using "gdbreplay". See gdbserver/README for
6425 details. This is useful when you have a problem with GDB while doing
6426 remote debugging; you can make a recording of the session and send it
6427 to someone else, who can then recreate the problem.
6429 * Speedups for remote debugging
6431 GDB includes speedups for downloading and stepping MIPS systems using
6432 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6433 and more efficient S-record downloading.
6435 * Memory use reductions and statistics collection
6437 GDB now uses less memory and reports statistics about memory usage.
6438 Try the `maint print statistics' command, for example.
6440 *** Changes in GDB-4.15:
6442 * Psymtabs for XCOFF
6444 The symbol reader for AIX GDB now uses partial symbol tables. This
6445 can greatly improve startup time, especially for large executables.
6447 * Remote targets use caching
6449 Remote targets now use a data cache to speed up communication with the
6450 remote side. The data cache could lead to incorrect results because
6451 it doesn't know about volatile variables, thus making it impossible to
6452 debug targets which use memory mapped I/O devices. `set remotecache
6453 off' turns the the data cache off.
6455 * Remote targets may have threads
6457 The standard remote protocol now includes support for multiple threads
6458 in the target system, using new protocol commands 'H' and 'T'. See
6459 gdb/remote.c for details.
6463 If GDB is configured with `--enable-netrom', then it will include
6464 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6465 acts as though it is a bank of ROM on the target board, but you can
6466 write into it over the network. GDB's support consists only of
6467 support for fast loading into the emulated ROM; to debug, you must use
6468 another protocol, such as standard remote protocol. The usual
6469 sequence is something like
6471 target nrom <netrom-hostname>
6473 target remote <netrom-hostname>:1235
6477 GDB now includes support for the Apple Macintosh, as a host only. It
6478 may be run as either an MPW tool or as a standalone application, and
6479 it can debug through the serial port. All the usual GDB commands are
6480 available, but to the target command, you must supply "serial" as the
6481 device type instead of "/dev/ttyXX". See mpw-README in the main
6482 directory for more information on how to build. The MPW configuration
6483 scripts */mpw-config.in support only a few targets, and only the
6484 mips-idt-ecoff target has been tested.
6488 GDB configuration now uses autoconf. This is not user-visible,
6489 but does simplify configuration and building.
6493 GDB now supports hpux10.
6495 *** Changes in GDB-4.14:
6497 * New native configurations
6499 x86 FreeBSD i[345]86-*-freebsd
6500 x86 NetBSD i[345]86-*-netbsd
6501 NS32k NetBSD ns32k-*-netbsd
6502 Sparc NetBSD sparc-*-netbsd
6506 A29K VxWorks a29k-*-vxworks
6507 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6508 CPU32 EST-300 emulator m68*-*-est*
6509 PowerPC ELF powerpc-*-elf
6512 * Alpha OSF/1 support for procfs
6514 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6515 possible to attach to running processes. As the mounting of the /proc
6516 filesystem is optional on the Alpha, GDB automatically determines
6517 the availability of /proc during startup. This can lead to problems
6518 if /proc is unmounted after GDB has been started.
6520 * Arguments to user-defined commands
6522 User commands may accept up to 10 arguments separated by whitespace.
6523 Arguments are accessed within the user command via $arg0..$arg9. A
6526 print $arg0 + $arg1 + $arg2
6528 To execute the command use:
6531 Defines the command "adder" which prints the sum of its three arguments.
6532 Note the arguments are text substitutions, so they may reference variables,
6533 use complex expressions, or even perform inferior function calls.
6535 * New `if' and `while' commands
6537 This makes it possible to write more sophisticated user-defined
6538 commands. Both commands take a single argument, which is the
6539 expression to evaluate, and must be followed by the commands to
6540 execute, one per line, if the expression is nonzero, the list being
6541 terminated by the word `end'. The `if' command list may include an
6542 `else' word, which causes the following commands to be executed only
6543 if the expression is zero.
6545 * Fortran source language mode
6547 GDB now includes partial support for Fortran 77. It will recognize
6548 Fortran programs and can evaluate a subset of Fortran expressions, but
6549 variables and functions may not be handled correctly. GDB will work
6550 with G77, but does not yet know much about symbols emitted by other
6553 * Better HPUX support
6555 Most debugging facilities now work on dynamic executables for HPPAs
6556 running hpux9 or later. You can attach to running dynamically linked
6557 processes, but by default the dynamic libraries will be read-only, so
6558 for instance you won't be able to put breakpoints in them. To change
6559 that behavior do the following before running the program:
6565 This will cause the libraries to be mapped private and read-write.
6566 To revert to the normal behavior, do this:
6572 You cannot set breakpoints or examine data in the library until after
6573 the library is loaded if the function/data symbols do not have
6576 GDB can now also read debug symbols produced by the HP C compiler on
6577 HPPAs (sorry, no C++, Fortran or 68k support).
6579 * Target byte order now dynamically selectable
6581 You can choose which byte order to use with a target system, via the
6582 commands "set endian big" and "set endian little", and you can see the
6583 current setting by using "show endian". You can also give the command
6584 "set endian auto", in which case GDB will use the byte order
6585 associated with the executable. Currently, only embedded MIPS
6586 configurations support dynamic selection of target byte order.
6588 * New DOS host serial code
6590 This version uses DPMI interrupts to handle buffered I/O, so you
6591 no longer need to run asynctsr when debugging boards connected to
6594 *** Changes in GDB-4.13:
6596 * New "complete" command
6598 This lists all the possible completions for the rest of the line, if it
6599 were to be given as a command itself. This is intended for use by emacs.
6601 * Trailing space optional in prompt
6603 "set prompt" no longer adds a space for you after the prompt you set. This
6604 allows you to set a prompt which ends in a space or one that does not.
6606 * Breakpoint hit counts
6608 "info break" now displays a count of the number of times the breakpoint
6609 has been hit. This is especially useful in conjunction with "ignore"; you
6610 can ignore a large number of breakpoint hits, look at the breakpoint info
6611 to see how many times the breakpoint was hit, then run again, ignoring one
6612 less than that number, and this will get you quickly to the last hit of
6615 * Ability to stop printing at NULL character
6617 "set print null-stop" will cause GDB to stop printing the characters of
6618 an array when the first NULL is encountered. This is useful when large
6619 arrays actually contain only short strings.
6621 * Shared library breakpoints
6623 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6624 breakpoints in shared libraries before the executable is run.
6626 * Hardware watchpoints
6628 There is a new hardware breakpoint for the watch command for sparclite
6629 targets. See gdb/sparclite/hw_breakpoint.note.
6631 Hardware watchpoints are also now supported under GNU/Linux.
6635 Annotations have been added. These are for use with graphical interfaces,
6636 and are still experimental. Currently only gdba.el uses these.
6638 * Improved Irix 5 support
6640 GDB now works properly with Irix 5.2.
6642 * Improved HPPA support
6644 GDB now works properly with the latest GCC and GAS.
6646 * New native configurations
6648 Sequent PTX4 i[34]86-sequent-ptx4
6649 HPPA running OSF/1 hppa*-*-osf*
6650 Atari TT running SVR4 m68*-*-sysv4*
6651 RS/6000 LynxOS rs6000-*-lynxos*
6655 OS/9000 i[34]86-*-os9k
6656 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6659 * Hitachi SH7000 and E7000-PC ICE support
6661 There is now support for communicating with the Hitachi E7000-PC ICE.
6662 This is available automatically when GDB is configured for the SH.
6666 As usual, a variety of small fixes and improvements, both generic
6667 and configuration-specific. See the ChangeLog for more detail.
6669 *** Changes in GDB-4.12:
6671 * Irix 5 is now supported
6675 GDB-4.12 on the HPPA has a number of changes which make it unable
6676 to debug the output from the currently released versions of GCC and
6677 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6678 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6679 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6682 *** Changes in GDB-4.11:
6684 * User visible changes:
6688 The "set remotedebug" option is now consistent between the mips remote
6689 target, remote targets using the gdb-specific protocol, UDI (AMD's
6690 debug protocol for the 29k) and the 88k bug monitor. It is now an
6691 integer specifying a debug level (normally 0 or 1, but 2 means more
6692 debugging info for the mips target).
6694 * DEC Alpha native support
6696 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6697 debug info, but GDB works fairly well with the DEC compiler and should
6698 work with a future GCC release. See the README file for a few
6699 Alpha-specific notes.
6701 * Preliminary thread implementation
6703 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6705 * LynxOS native and target support for 386
6707 This release has been hosted on LynxOS 2.2, and also can be configured
6708 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6711 * Improvements in C++ mangling/demangling.
6713 This release has much better g++ debugging, specifically in name
6714 mangling/demangling, virtual function calls, print virtual table,
6715 call methods, ...etc.
6717 *** Changes in GDB-4.10:
6719 * User visible changes:
6721 Remote debugging using the GDB-specific (`target remote') protocol now
6722 supports the `load' command. This is only useful if you have some
6723 other way of getting the stub to the target system, and you can put it
6724 somewhere in memory where it won't get clobbered by the download.
6726 Filename completion now works.
6728 When run under emacs mode, the "info line" command now causes the
6729 arrow to point to the line specified. Also, "info line" prints
6730 addresses in symbolic form (as well as hex).
6732 All vxworks based targets now support a user settable option, called
6733 vxworks-timeout. This option represents the number of seconds gdb
6734 should wait for responses to rpc's. You might want to use this if
6735 your vxworks target is, perhaps, a slow software simulator or happens
6736 to be on the far side of a thin network line.
6740 This release contains support for using a DEC alpha as a GDB host for
6741 cross debugging. Native alpha debugging is not supported yet.
6744 *** Changes in GDB-4.9:
6748 This is the first GDB release which is accompanied by a matching testsuite.
6749 The testsuite requires installation of dejagnu, which should be available
6750 via ftp from most sites that carry GNU software.
6754 'Cfront' style demangling has had its name changed to 'ARM' style, to
6755 emphasize that it was written from the specifications in the C++ Annotated
6756 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6757 disclaimers, it still generated too much confusion with users attempting to
6758 use gdb with AT&T cfront.
6762 GDB now uses a standard remote interface to a simulator library.
6763 So far, the library contains simulators for the Zilog Z8001/2, the
6764 Hitachi H8/300, H8/500 and Super-H.
6766 * New targets supported
6768 H8/300 simulator h8300-hitachi-hms or h8300hms
6769 H8/500 simulator h8500-hitachi-hms or h8500hms
6770 SH simulator sh-hitachi-hms or sh
6771 Z8000 simulator z8k-zilog-none or z8ksim
6772 IDT MIPS board over serial line mips-idt-ecoff
6774 Cross-debugging to GO32 targets is supported. It requires a custom
6775 version of the i386-stub.c module which is integrated with the
6776 GO32 memory extender.
6778 * New remote protocols
6780 MIPS remote debugging protocol.
6782 * New source languages supported
6784 This version includes preliminary support for Chill, a Pascal like language
6785 used by telecommunications companies. Chill support is also being integrated
6786 into the GNU compiler, but we don't know when it will be publically available.
6789 *** Changes in GDB-4.8:
6791 * HP Precision Architecture supported
6793 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6794 version of this support was available as a set of patches from the
6795 University of Utah. GDB does not support debugging of programs
6796 compiled with the HP compiler, because HP will not document their file
6797 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6798 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6800 Many problems in the preliminary version have been fixed.
6802 * Faster and better demangling
6804 We have improved template demangling and fixed numerous bugs in the GNU style
6805 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6806 character types (wchar_t) are now supported. Demangling of each symbol is now
6807 only done once, and is cached when the symbol table for a file is read in.
6808 This results in a small increase in memory usage for C programs, a moderate
6809 increase in memory usage for C++ programs, and a fantastic speedup in
6812 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6813 from the specifications in the Annotated Reference Manual, which AT&T's
6814 compiler does not actually implement.
6816 * G++ multiple inheritance compiler problem
6818 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6819 inheritance lattices was reworked to properly discover ambiguities. We
6820 recently found an example which causes this new algorithm to fail in a
6821 very subtle way, producing bad debug information for those classes.
6822 The file 'gcc.patch' (in this directory) can be applied to gcc to
6823 circumvent the problem. A future GCC release will contain a complete
6826 The previous G++ debug info problem (mentioned below for the gdb-4.7
6827 release) is fixed in gcc version 2.3.2.
6829 * Improved configure script
6831 The `configure' script will now attempt to guess your system type if
6832 you don't supply a host system type. The old scheme of supplying a
6833 host system triplet is preferable over using this. All the magic is
6834 done in the new `config.guess' script. Examine it for details.
6836 We have also brought our configure script much more in line with the FSF's
6837 version. It now supports the --with-xxx options. In particular,
6838 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6839 The resulting GDB will not be able to read arbitrary object file formats --
6840 only the format ``expected'' to be used on the configured target system.
6841 We hope to make this the default in a future release.
6843 * Documentation improvements
6845 There's new internal documentation on how to modify GDB, and how to
6846 produce clean changes to the code. We implore people to read it
6847 before submitting changes.
6849 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6850 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6851 `info' files are also provided. To build `info' files from scratch,
6852 you will need the latest `makeinfo' release, which will be available in
6853 a future texinfo-X.Y release.
6855 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6856 We're not sure exactly which versions have this problem, but it has
6857 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6858 or better. If that isn't possible, there is a patch in
6859 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6860 around this problem.
6864 GDB now supports array constants that can be used in expressions typed in by
6865 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6866 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6869 The new directory `gdb/sparclite' contains a program that demonstrates
6870 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6872 * New native hosts supported
6874 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6875 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6877 * New targets supported
6879 AMD 29k family via UDI a29k-amd-udi or udi29k
6881 * New file formats supported
6883 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6884 HPUX core files, and SCO 3.2v2 core files.
6888 Attaching to processes now works again; thanks for the many bug reports.
6890 We have also stomped on a bunch of core dumps caused by
6891 printf_filtered("%s") problems.
6893 We eliminated a copyright problem on the rpc and ptrace header files
6894 for VxWorks, which was discovered at the last minute during the 4.7
6895 release. You should now be able to build a VxWorks GDB.
6897 You can now interrupt gdb while an attached process is running. This
6898 will cause the attached process to stop, and give control back to GDB.
6900 We fixed problems caused by using too many file descriptors
6901 for reading symbols from object files and libraries. This was
6902 especially a problem for programs that used many (~100) shared
6905 The `step' command now only enters a subroutine if there is line number
6906 information for the subroutine. Otherwise it acts like the `next'
6907 command. Previously, `step' would enter subroutines if there was
6908 any debugging information about the routine. This avoids problems
6909 when using `cc -g1' on MIPS machines.
6911 * Internal improvements
6913 GDB's internal interfaces have been improved to make it easier to support
6914 debugging of multiple languages in the future.
6916 GDB now uses a common structure for symbol information internally.
6917 Minimal symbols (derived from linkage symbols in object files), partial
6918 symbols (from a quick scan of debug information), and full symbols
6919 contain a common subset of information, making it easier to write
6920 shared code that handles any of them.
6922 * New command line options
6924 We now accept --silent as an alias for --quiet.
6928 The memory-mapped-malloc library is now licensed under the GNU Library
6929 General Public License.
6931 *** Changes in GDB-4.7:
6933 * Host/native/target split
6935 GDB has had some major internal surgery to untangle the support for
6936 hosts and remote targets. Now, when you configure GDB for a remote
6937 target, it will no longer load in all of the support for debugging
6938 local programs on the host. When fully completed and tested, this will
6939 ensure that arbitrary host/target combinations are possible.
6941 The primary conceptual shift is to separate the non-portable code in
6942 GDB into three categories. Host specific code is required any time GDB
6943 is compiled on that host, regardless of the target. Target specific
6944 code relates to the peculiarities of the target, but can be compiled on
6945 any host. Native specific code is everything else: it can only be
6946 built when the host and target are the same system. Child process
6947 handling and core file support are two common `native' examples.
6949 GDB's use of /proc for controlling Unix child processes is now cleaner.
6950 It has been split out into a single module under the `target_ops' vector,
6951 plus two native-dependent functions for each system that uses /proc.
6953 * New hosts supported
6955 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6956 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6957 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6959 * New targets supported
6961 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6962 68030 and CPU32 m68030-*-*, m68332-*-*
6964 * New native hosts supported
6966 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6967 (386bsd is not well tested yet)
6968 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6970 * New file formats supported
6972 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6973 supports reading of `a.out.adobe' object files, which are an a.out
6974 format extended with minimal information about multiple sections.
6978 `show copying' is the same as the old `info copying'.
6979 `show warranty' is the same as `info warrantee'.
6980 These were renamed for consistency. The old commands continue to work.
6982 `info handle' is a new alias for `info signals'.
6984 You can now define pre-command hooks, which attach arbitrary command
6985 scripts to any command. The commands in the hook will be executed
6986 prior to the user's command. You can also create a hook which will be
6987 executed whenever the program stops. See gdb.texinfo.
6991 We now deal with Cfront style name mangling, and can even extract type
6992 info from mangled symbols. GDB can automatically figure out which
6993 symbol mangling style your C++ compiler uses.
6995 Calling of methods and virtual functions has been improved as well.
6999 The crash that occured when debugging Sun Ansi-C compiled binaries is
7000 fixed. This was due to mishandling of the extra N_SO stabs output
7003 We also finally got Ultrix 4.2 running in house, and fixed core file
7004 support, with help from a dozen people on the net.
7006 John M. Farrell discovered that the reason that single-stepping was so
7007 slow on all of the Mips based platforms (primarily SGI and DEC) was
7008 that we were trying to demangle and lookup a symbol used for internal
7009 purposes on every instruction that was being stepped through. Changing
7010 the name of that symbol so that it couldn't be mistaken for a C++
7011 mangled symbol sped things up a great deal.
7013 Rich Pixley sped up symbol lookups in general by getting much smarter
7014 about when C++ symbol mangling is necessary. This should make symbol
7015 completion (TAB on the command line) much faster. It's not as fast as
7016 we'd like, but it's significantly faster than gdb-4.6.
7020 A new user controllable variable 'call_scratch_address' can
7021 specify the location of a scratch area to be used when GDB
7022 calls a function in the target. This is necessary because the
7023 usual method of putting the scratch area on the stack does not work
7024 in systems that have separate instruction and data spaces.
7026 We integrated changes to support the 29k UDI (Universal Debugger
7027 Interface), but discovered at the last minute that we didn't have all
7028 of the appropriate copyright paperwork. We are working with AMD to
7029 resolve this, and hope to have it available soon.
7033 We have sped up the remote serial line protocol, especially for targets
7034 with lots of registers. It now supports a new `expedited status' ('T')
7035 message which can be used in place of the existing 'S' status message.
7036 This allows the remote stub to send only the registers that GDB
7037 needs to make a quick decision about single-stepping or conditional
7038 breakpoints, eliminating the need to fetch the entire register set for
7039 each instruction being stepped through.
7041 The GDB remote serial protocol now implements a write-through cache for
7042 registers, only re-reading the registers if the target has run.
7044 There is also a new remote serial stub for SPARC processors. You can
7045 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
7046 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
7047 processor with a serial port.
7051 Configure.in files have become much easier to read and modify. A new
7052 `table driven' format makes it more obvious what configurations are
7053 supported, and what files each one uses.
7057 There is a new opcodes library which will eventually contain all of the
7058 disassembly routines and opcode tables. At present, it only contains
7059 Sparc and Z8000 routines. This will allow the assembler, debugger, and
7060 disassembler (binutils/objdump) to share these routines.
7062 The libiberty library is now copylefted under the GNU Library General
7063 Public License. This allows more liberal use, and was done so libg++
7064 can use it. This makes no difference to GDB, since the Library License
7065 grants all the rights from the General Public License.
7069 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
7070 reference to the stabs symbol info used by the debugger. It is (as far
7071 as we know) the only published document on this fascinating topic. We
7072 encourage you to read it, compare it to the stabs information on your
7073 system, and send improvements on the document in general (to
7074 bug-gdb@prep.ai.mit.edu).
7076 And, of course, many bugs have been fixed.
7079 *** Changes in GDB-4.6:
7081 * Better support for C++ function names
7083 GDB now accepts as input the "demangled form" of C++ overloaded function
7084 names and member function names, and can do command completion on such names
7085 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
7086 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
7087 Make use of command completion, it is your friend.
7089 GDB also now accepts a variety of C++ mangled symbol formats. They are
7090 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
7091 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
7092 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
7093 for the list of formats.
7095 * G++ symbol mangling problem
7097 Recent versions of gcc have a bug in how they emit debugging information for
7098 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
7099 directory) can be applied to gcc to fix the problem. Alternatively, if you
7100 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
7101 usual symptom is difficulty with setting breakpoints on methods. GDB complains
7102 about the method being non-existent. (We believe that version 2.2.2 of GCC has
7105 * New 'maintenance' command
7107 All of the commands related to hacking GDB internals have been moved out of
7108 the main command set, and now live behind the 'maintenance' command. This
7109 can also be abbreviated as 'mt'. The following changes were made:
7111 dump-me -> maintenance dump-me
7112 info all-breakpoints -> maintenance info breakpoints
7113 printmsyms -> maintenance print msyms
7114 printobjfiles -> maintenance print objfiles
7115 printpsyms -> maintenance print psymbols
7116 printsyms -> maintenance print symbols
7118 The following commands are new:
7120 maintenance demangle Call internal GDB demangler routine to
7121 demangle a C++ link name and prints the result.
7122 maintenance print type Print a type chain for a given symbol
7124 * Change to .gdbinit file processing
7126 We now read the $HOME/.gdbinit file before processing the argv arguments
7127 (e.g. reading symbol files or core files). This allows global parameters to
7128 be set, which will apply during the symbol reading. The ./.gdbinit is still
7129 read after argv processing.
7131 * New hosts supported
7133 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
7135 GNU/Linux support i386-unknown-linux or linux
7137 We are also including code to support the HP/PA running BSD and HPUX. This
7138 is almost guaranteed not to work, as we didn't have time to test or build it
7139 for this release. We are including it so that the more adventurous (or
7140 masochistic) of you can play with it. We also had major problems with the
7141 fact that the compiler that we got from HP doesn't support the -g option.
7144 * New targets supported
7146 Hitachi H8/300 h8300-hitachi-hms or h8300hms
7148 * More smarts about finding #include files
7150 GDB now remembers the compilation directory for all include files, and for
7151 all files from which C is generated (like yacc and lex sources). This
7152 greatly improves GDB's ability to find yacc/lex sources, and include files,
7153 especially if you are debugging your program from a directory different from
7154 the one that contains your sources.
7156 We also fixed a bug which caused difficulty with listing and setting
7157 breakpoints in include files which contain C code. (In the past, you had to
7158 try twice in order to list an include file that you hadn't looked at before.)
7160 * Interesting infernals change
7162 GDB now deals with arbitrary numbers of sections, where the symbols for each
7163 section must be relocated relative to that section's landing place in the
7164 target's address space. This work was needed to support ELF with embedded
7165 stabs used by Solaris-2.0.
7167 * Bug fixes (of course!)
7169 There have been loads of fixes for the following things:
7170 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
7171 i960, stabs, DOS(GO32), procfs, etc...
7173 See the ChangeLog for details.
7175 *** Changes in GDB-4.5:
7177 * New machines supported (host and target)
7179 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
7181 SGI Irix-4.x mips-sgi-irix4 or iris4
7183 * New malloc package
7185 GDB now uses a new memory manager called mmalloc, based on gmalloc.
7186 Mmalloc is capable of handling mutiple heaps of memory. It is also
7187 capable of saving a heap to a file, and then mapping it back in later.
7188 This can be used to greatly speedup the startup of GDB by using a
7189 pre-parsed symbol table which lives in a mmalloc managed heap. For
7190 more details, please read mmalloc/mmalloc.texi.
7194 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
7195 'help info proc' for details.
7197 * MIPS ecoff symbol table format
7199 The code that reads MIPS symbol table format is now supported on all hosts.
7200 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
7203 * File name changes for MS-DOS
7205 Many files in the config directories have been renamed to make it easier to
7206 support GDB on MS-DOSe systems (which have very restrictive file name
7207 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
7208 environment) is close to working but has some remaining problems. Note
7209 that debugging of DOS programs is not supported, due to limitations
7210 in the ``operating system'', but it can be used to host cross-debugging.
7212 * Cross byte order fixes
7214 Many fixes have been made to support cross debugging of Sparc and MIPS
7215 targets from hosts whose byte order differs.
7217 * New -mapped and -readnow options
7219 If memory-mapped files are available on your system through the 'mmap'
7220 system call, you can use the -mapped option on the `file' or
7221 `symbol-file' commands to cause GDB to write the symbols from your
7222 program into a reusable file. If the program you are debugging is
7223 called `/path/fred', the mapped symbol file will be `./fred.syms'.
7224 Future GDB debugging sessions will notice the presence of this file,
7225 and will quickly map in symbol information from it, rather than reading
7226 the symbol table from the executable program. Using the '-mapped'
7227 option in a GDB `file' or `symbol-file' command has the same effect as
7228 starting GDB with the '-mapped' command-line option.
7230 You can cause GDB to read the entire symbol table immediately by using
7231 the '-readnow' option with any of the commands that load symbol table
7232 information (or on the GDB command line). This makes the command
7233 slower, but makes future operations faster.
7235 The -mapped and -readnow options are typically combined in order to
7236 build a `fred.syms' file that contains complete symbol information.
7237 A simple GDB invocation to do nothing but build a `.syms' file for future
7240 gdb -batch -nx -mapped -readnow programname
7242 The `.syms' file is specific to the host machine on which GDB is run.
7243 It holds an exact image of GDB's internal symbol table. It cannot be
7244 shared across multiple host platforms.
7246 * longjmp() handling
7248 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
7249 siglongjmp() without losing control. This feature has not yet been ported to
7250 all systems. It currently works on many 386 platforms, all MIPS-based
7251 platforms (SGI, DECstation, etc), and Sun3/4.
7255 Preliminary work has been put in to support the new Solaris OS from Sun. At
7256 this time, it can control and debug processes, but it is not capable of
7261 As always, many many bug fixes. The major areas were with g++, and mipsread.
7262 People using the MIPS-based platforms should experience fewer mysterious
7263 crashes and trashed symbol tables.
7265 *** Changes in GDB-4.4:
7267 * New machines supported (host and target)
7269 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7271 BSD Reno on Vax vax-dec-bsd
7272 Ultrix on Vax vax-dec-ultrix
7274 * New machines supported (target)
7276 AMD 29000 embedded, using EBMON a29k-none-none
7280 GDB continues to improve its handling of C++. `References' work better.
7281 The demangler has also been improved, and now deals with symbols mangled as
7282 per the Annotated C++ Reference Guide.
7284 GDB also now handles `stabs' symbol information embedded in MIPS
7285 `ecoff' symbol tables. Since the ecoff format was not easily
7286 extensible to handle new languages such as C++, this appeared to be a
7287 good way to put C++ debugging info into MIPS binaries. This option
7288 will be supported in the GNU C compiler, version 2, when it is
7291 * New features for SVR4
7293 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7294 shared libraries. Debugging dynamically linked programs should present
7295 only minor differences from debugging statically linked programs.
7297 The `info proc' command will print out information about any process
7298 on an SVR4 system (including the one you are debugging). At the moment,
7299 it prints the address mappings of the process.
7301 If you bring up GDB on another SVR4 system, please send mail to
7302 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7304 * Better dynamic linking support in SunOS
7306 Reading symbols from shared libraries which contain debugging symbols
7307 now works properly. However, there remain issues such as automatic
7308 skipping of `transfer vector' code during function calls, which
7309 make it harder to debug code in a shared library, than to debug the
7310 same code linked statically.
7314 GDB is now using the latest `getopt' routines from the FSF. This
7315 version accepts the -- prefix for options with long names. GDB will
7316 continue to accept the old forms (-option and +option) as well.
7317 Various single letter abbreviations for options have been explicity
7318 added to the option table so that they won't get overshadowed in the
7319 future by other options that begin with the same letter.
7323 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7324 Many assorted bugs have been handled. Many more remain to be handled.
7325 See the various ChangeLog files (primarily in gdb and bfd) for details.
7328 *** Changes in GDB-4.3:
7330 * New machines supported (host and target)
7332 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7333 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7334 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7336 * Almost SCO Unix support
7338 We had hoped to support:
7339 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7340 (except for core file support), but we discovered very late in the release
7341 that it has problems with process groups that render gdb unusable. Sorry
7342 about that. I encourage people to fix it and post the fixes.
7344 * Preliminary ELF and DWARF support
7346 GDB can read ELF object files on System V Release 4, and can handle
7347 debugging records for C, in DWARF format, in ELF files. This support
7348 is preliminary. If you bring up GDB on another SVR4 system, please
7349 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7354 GDB now uses the latest `readline' library. One user-visible change
7355 is that two tabs will list possible command completions, which previously
7356 required typing M-? (meta-question mark, or ESC ?).
7360 The `stepi' bug that many of you noticed has been squashed.
7361 Many bugs in C++ have been handled. Many more remain to be handled.
7362 See the various ChangeLog files (primarily in gdb and bfd) for details.
7364 * State of the MIPS world (in case you wondered):
7366 GDB can understand the symbol tables emitted by the compilers
7367 supplied by most vendors of MIPS-based machines, including DEC. These
7368 symbol tables are in a format that essentially nobody else uses.
7370 Some versions of gcc come with an assembler post-processor called
7371 mips-tfile. This program is required if you want to do source-level
7372 debugging of gcc-compiled programs. I believe FSF does not ship
7373 mips-tfile with gcc version 1, but it will eventually come with gcc
7376 Debugging of g++ output remains a problem. g++ version 1.xx does not
7377 really support it at all. (If you're lucky, you should be able to get
7378 line numbers and stack traces to work, but no parameters or local
7379 variables.) With some work it should be possible to improve the
7382 When gcc version 2 is released, you will have somewhat better luck.
7383 However, even then you will get confusing results for inheritance and
7386 We will eventually provide full debugging of g++ output on
7387 DECstations. This will probably involve some kind of stabs-in-ecoff
7388 encapulation, but the details have not been worked out yet.
7391 *** Changes in GDB-4.2:
7393 * Improved configuration
7395 Only one copy of `configure' exists now, and it is not self-modifying.
7396 Porting BFD is simpler.
7400 The `step' and `next' commands now only stop at the first instruction
7401 of a source line. This prevents the multiple stops that used to occur
7402 in switch statements, for-loops, etc. `Step' continues to stop if a
7403 function that has debugging information is called within the line.
7407 Lots of small bugs fixed. More remain.
7409 * New host supported (not target)
7411 Intel 386 PC clone running Mach i386-none-mach
7414 *** Changes in GDB-4.1:
7416 * Multiple source language support
7418 GDB now has internal scaffolding to handle several source languages.
7419 It determines the type of each source file from its filename extension,
7420 and will switch expression parsing and number formatting to match the
7421 language of the function in the currently selected stack frame.
7422 You can also specifically set the language to be used, with
7423 `set language c' or `set language modula-2'.
7427 GDB now has preliminary support for the GNU Modula-2 compiler,
7428 currently under development at the State University of New York at
7429 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7430 continue through the fall of 1991 and into 1992.
7432 Other Modula-2 compilers are currently not supported, and attempting to
7433 debug programs compiled with them will likely result in an error as the
7434 symbol table is read. Feel free to work on it, though!
7436 There are hooks in GDB for strict type checking and range checking,
7437 in the `Modula-2 philosophy', but they do not currently work.
7441 GDB can now write to executable and core files (e.g. patch
7442 a variable's value). You must turn this switch on, specify
7443 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7444 by assigning a new value to a variable. Modifications take
7447 * Automatic SunOS shared library reading
7449 When you run your program, GDB automatically determines where its
7450 shared libraries (if any) have been loaded, and reads their symbols.
7451 The `share' command is no longer needed. This also works when
7452 examining core files.
7456 You can specify the number of lines that the `list' command shows.
7459 * New machines supported (host and target)
7461 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7462 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7463 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7465 * New hosts supported (not targets)
7467 IBM RT/PC: romp-ibm-aix or rtpc
7469 * New targets supported (not hosts)
7471 AMD 29000 embedded with COFF a29k-none-coff
7472 AMD 29000 embedded with a.out a29k-none-aout
7473 Ultracomputer remote kernel debug a29k-nyu-kern
7475 * New remote interfaces
7481 *** Changes in GDB-4.0:
7485 Wide output is wrapped at good places to make the output more readable.
7487 Gdb now supports cross-debugging from a host machine of one type to a
7488 target machine of another type. Communication with the target system
7489 is over serial lines. The ``target'' command handles connecting to the
7490 remote system; the ``load'' command will download a program into the
7491 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7492 also supports debugging of realtime processes running under VxWorks,
7493 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7494 stub on the target system.
7496 New CPUs supported include the AMD 29000 and Intel 960.
7498 GDB now reads object files and symbol tables via a ``binary file''
7499 library, which allows a single copy of GDB to debug programs of multiple
7500 object file types such as a.out and coff.
7502 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7503 refcard.dvi and refcard.ps are available to format it).
7506 * Control-Variable user interface simplified
7508 All variables that control the operation of the debugger can be set
7509 by the ``set'' command, and displayed by the ``show'' command.
7511 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7512 ``Show prompt'' produces the response:
7513 Gdb's prompt is new-gdb=>.
7515 What follows are the NEW set commands. The command ``help set'' will
7516 print a complete list of old and new set commands. ``help set FOO''
7517 will give a longer description of the variable FOO. ``show'' will show
7518 all of the variable descriptions and their current settings.
7520 confirm on/off: Enables warning questions for operations that are
7521 hard to recover from, e.g. rerunning the program while
7522 it is already running. Default is ON.
7524 editing on/off: Enables EMACS style command line editing
7525 of input. Previous lines can be recalled with
7526 control-P, the current line can be edited with control-B,
7527 you can search for commands with control-R, etc.
7530 history filename NAME: NAME is where the gdb command history
7531 will be stored. The default is .gdb_history,
7532 or the value of the environment variable
7535 history size N: The size, in commands, of the command history. The
7536 default is 256, or the value of the environment variable
7539 history save on/off: If this value is set to ON, the history file will
7540 be saved after exiting gdb. If set to OFF, the
7541 file will not be saved. The default is OFF.
7543 history expansion on/off: If this value is set to ON, then csh-like
7544 history expansion will be performed on
7545 command line input. The default is OFF.
7547 radix N: Sets the default radix for input and output. It can be set
7548 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7549 in the current radix, so "set radix 10" is always a no-op.
7551 height N: This integer value is the number of lines on a page. Default
7552 is 24, the current `stty rows'' setting, or the ``li#''
7553 setting from the termcap entry matching the environment
7556 width N: This integer value is the number of characters on a line.
7557 Default is 80, the current `stty cols'' setting, or the ``co#''
7558 setting from the termcap entry matching the environment
7561 Note: ``set screensize'' is obsolete. Use ``set height'' and
7562 ``set width'' instead.
7564 print address on/off: Print memory addresses in various command displays,
7565 such as stack traces and structure values. Gdb looks
7566 more ``symbolic'' if you turn this off; it looks more
7567 ``machine level'' with it on. Default is ON.
7569 print array on/off: Prettyprint arrays. New convenient format! Default
7572 print demangle on/off: Print C++ symbols in "source" form if on,
7575 print asm-demangle on/off: Same, for assembler level printouts
7578 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7581 * Support for Epoch Environment.
7583 The epoch environment is a version of Emacs v18 with windowing. One
7584 new command, ``inspect'', is identical to ``print'', except that if you
7585 are running in the epoch environment, the value is printed in its own
7589 * Support for Shared Libraries
7591 GDB can now debug programs and core files that use SunOS shared libraries.
7592 Symbols from a shared library cannot be referenced
7593 before the shared library has been linked with the program (this
7594 happens after you type ``run'' and before the function main() is entered).
7595 At any time after this linking (including when examining core files
7596 from dynamically linked programs), gdb reads the symbols from each
7597 shared library when you type the ``sharedlibrary'' command.
7598 It can be abbreviated ``share''.
7600 sharedlibrary REGEXP: Load shared object library symbols for files
7601 matching a unix regular expression. No argument
7602 indicates to load symbols for all shared libraries.
7604 info sharedlibrary: Status of loaded shared libraries.
7609 A watchpoint stops execution of a program whenever the value of an
7610 expression changes. Checking for this slows down execution
7611 tremendously whenever you are in the scope of the expression, but is
7612 quite useful for catching tough ``bit-spreader'' or pointer misuse
7613 problems. Some machines such as the 386 have hardware for doing this
7614 more quickly, and future versions of gdb will use this hardware.
7616 watch EXP: Set a watchpoint (breakpoint) for an expression.
7618 info watchpoints: Information about your watchpoints.
7620 delete N: Deletes watchpoint number N (same as breakpoints).
7621 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7622 enable N: Re-enables watchpoint number N (same as breakpoints).
7625 * C++ multiple inheritance
7627 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7630 * C++ exception handling
7632 Gdb now supports limited C++ exception handling. Besides the existing
7633 ability to breakpoint on an exception handler, gdb can breakpoint on
7634 the raising of an exception (before the stack is peeled back to the
7637 catch FOO: If there is a FOO exception handler in the dynamic scope,
7638 set a breakpoint to catch exceptions which may be raised there.
7639 Multiple exceptions (``catch foo bar baz'') may be caught.
7641 info catch: Lists all exceptions which may be caught in the
7642 current stack frame.
7645 * Minor command changes
7647 The command ``call func (arg, arg, ...)'' now acts like the print
7648 command, except it does not print or save a value if the function's result
7649 is void. This is similar to dbx usage.
7651 The ``up'' and ``down'' commands now always print the frame they end up
7652 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7653 frames without printing.
7655 * New directory command
7657 'dir' now adds directories to the FRONT of the source search path.
7658 The path starts off empty. Source files that contain debug information
7659 about the directory in which they were compiled can be found even
7660 with an empty path; Sun CC and GCC include this information. If GDB can't
7661 find your source file in the current directory, type "dir .".
7663 * Configuring GDB for compilation
7665 For normal use, type ``./configure host''. See README or gdb.texinfo
7668 GDB now handles cross debugging. If you are remotely debugging between
7669 two different machines, type ``./configure host -target=targ''.
7670 Host is the machine where GDB will run; targ is the machine
7671 where the program that you are debugging will run.