1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 8.3
6 * New built-in convenience variables $_gdb_major and $_gdb_minor
7 provide the GDB version. They are handy for conditionally using
8 features available only in or since specific GDB versions, in
9 scripts that should work error-free with many different versions,
10 such as in system-wide init files.
12 * GDB now supports Thread Local Storage (TLS) variables on several
13 FreeBSD architectures (amd64, i386, powerpc, riscv). Other
14 architectures require kernel changes. TLS is not yet supported for
15 amd64 and i386 process core dumps.
17 * Support for Pointer Authentication on AArch64 Linux.
19 * Two new convenience functions $_cimag and $_creal that extract the
20 imaginary and real parts respectively from complex numbers.
24 ** The gdb.Value type has a new method 'format_string' which returns a
25 string representing the value. The formatting is controlled by the
26 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
27 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
28 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
30 * New built-in convenience variables $_shell_exitcode and $_shell_exitsignal
31 provide the exitcode or exit status of the shell commands launched by
32 GDB commands such as "shell", "pipe" and "make".
36 | [COMMAND] | SHELL_COMMAND
37 | -d DELIM COMMAND DELIM SHELL_COMMAND
38 pipe [COMMAND] | SHELL_COMMAND
39 pipe -d DELIM COMMAND DELIM SHELL_COMMAND
40 Executes COMMAND and sends its output to SHELL_COMMAND.
41 With no COMMAND, repeat the last executed command
42 and send its output to SHELL_COMMAND.
44 set may-call-functions [on|off]
45 show may-call-functions
46 This controls whether GDB will attempt to call functions in
47 the program, such as with expressions in the print command. It
48 defaults to on. Calling functions in the program being debugged
49 can have undesired side effects. It is now possible to forbid
50 such function calls. If function calls are forbidden, GDB will throw
51 an error when a command (such as print expression) calls a function
54 set print finish [on|off]
56 This controls whether the `finish' command will display the value
57 that is returned by the current function. When `off', the value is
58 still entered into the value history, but it is not printed. The
63 Allows deeply nested structures to be simplified when printing by
64 replacing deeply nested parts (beyond the max-depth) with ellipses.
65 The default max-depth is 20, but this can be set to unlimited to get
66 the old behavior back.
68 set logging debugredirect [on|off]
69 By default, GDB debug output will go to both the terminal and the logfile.
70 Set if you want debug output to go only to the log file.
72 set style title foreground COLOR
73 set style title background COLOR
74 set style title intensity VALUE
75 Control the styling of titles.
77 set style highlight foreground COLOR
78 set style highlight background COLOR
79 set style highlight intensity VALUE
80 Control the styling of highlightings.
85 The "help" command uses the title style to enhance the
86 readibility of its output by styling the classes and
90 Similarly to "help", the "apropos" command also uses the
91 title style for the command names. "apropos" accepts now
92 a flag "-v" (verbose) to show the full documentation
93 of matching commands and to use the highlight style to mark
94 the documentation parts matching REGEXP.
97 The "show style" and its subcommands are now styling
98 a style name in their output using its own style, to help
99 the user visualize the different styles.
105 This lists all the possible completions for the rest of the line, if it
106 were to be given as a command itself. This is intended for use by MI
107 frontends in cases when separate CLI and MI channels cannot be used.
111 The testsuite now creates the files gdb.cmd (containing the arguments
112 used to launch GDB) and gdb.in (containing all the commands sent to
113 GDB) in the output directory for each test script. Multiple invocations
114 are appended with .1, .2, .3 etc.
116 *** Changes in GDB 8.3
118 * GDB and GDBserver now support access to additional registers on
119 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
122 * GDB now has experimental support for the compilation and injection of
123 C++ source code into the inferior. This beta release does not include
124 support for several language features, such as templates, constructors,
127 This feature requires GCC 7.1 or higher built with libcp1.so
130 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
131 can be passed using the '[ADDRESS]:PORT' notation, or the regular
132 'ADDRESS:PORT' method.
134 * DWARF index cache: GDB can now automatically save indices of DWARF
135 symbols on disk to speed up further loading of the same binaries.
137 * Ada task switching is now supported on aarch64-elf targets when
138 debugging a program using the Ravenscar Profile. For more information,
139 see the "Tasking Support when using the Ravenscar Profile" section
140 in the GDB user manual.
142 * GDB in batch mode now exits with status 1 if the last command to be
145 * The RISC-V target now supports target descriptions.
147 * System call catchpoints now support system call aliases on FreeBSD.
148 When the ABI of a system call changes in FreeBSD, this is
149 implemented by leaving a compatibility system call using the old ABI
150 at the existing number and allocating a new system call number for
151 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
152 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
153 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
154 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
155 so that a system call catchpoint for the 'kevent' system call will
156 catch invocations of both the 'kevent' and 'freebsd11_kevent'
157 binaries. This ensures that 'kevent' system calls are caught for
158 binaries using either the old or new ABIs.
160 * Terminal styling is now available for the CLI and the TUI. GNU
161 Source Highlight can additionally be used to provide styling of
162 source code snippets. See the "set style" commands, below, for more
165 * Removed support for old demangling styles arm, edg, gnu, hp and
170 set debug compile-cplus-types
171 show debug compile-cplus-types
172 Control the display of debug output about type conversion in the
173 C++ compile feature. Commands have no effect while compiliong
178 Control whether debug output about files/functions skipping is
181 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
182 Apply a command to some frames.
183 FLAG arguments allow to control what output to produce and how to handle
184 errors raised when applying COMMAND to a frame.
187 Apply a command to all threads (ignoring errors and empty output).
188 Shortcut for 'thread apply all -s COMMAND'.
191 Apply a command to all frames (ignoring errors and empty output).
192 Shortcut for 'frame apply all -s COMMAND'.
195 Apply a command to all frames of all threads (ignoring errors and empty
197 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
199 maint set dwarf unwinders (on|off)
200 maint show dwarf unwinders
201 Control whether DWARF unwinders can be used.
204 Display a list of open files for a process.
208 Changes to the "frame", "select-frame", and "info frame" CLI commands.
209 These commands all now take a frame specification which
210 is either a frame level, or one of the keywords 'level', 'address',
211 'function', or 'view' followed by a parameter. Selecting a frame by
212 address, or viewing a frame outside the current backtrace now
213 requires the use of a keyword. Selecting a frame by level is
214 unchanged. The MI comment "-stack-select-frame" is unchanged.
216 target remote FILENAME
217 target extended-remote FILENAME
218 If FILENAME is a Unix domain socket, GDB will attempt to connect
219 to this socket instead of opening FILENAME as a character device.
221 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
222 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
223 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
224 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
225 These commands can now print only the searched entities
226 matching the provided regexp(s), giving a condition
227 on the entity names or entity types. The flag -q disables
228 printing headers or informations messages.
234 These commands now determine the syntax for the shown entities
235 according to the language chosen by `set language'. In particular,
236 `set language auto' means to automatically choose the language of
239 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
240 The 'thread apply' command accepts new FLAG arguments.
241 FLAG arguments allow to control what output to produce and how to handle
242 errors raised when applying COMMAND to a thread.
244 set tui tab-width NCHARS
245 show tui tab-width NCHARS
246 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
248 set style enabled [on|off]
250 Enable or disable terminal styling. Styling is enabled by default
251 on most hosts, but disabled by default when in batch mode.
253 set style sources [on|off]
255 Enable or disable source code styling. Source code styling is
256 enabled by default, but only takes effect if styling in general is
257 enabled, and if GDB was linked with GNU Source Highlight.
259 set style filename foreground COLOR
260 set style filename background COLOR
261 set style filename intensity VALUE
262 Control the styling of file names.
264 set style function foreground COLOR
265 set style function background COLOR
266 set style function intensity VALUE
267 Control the styling of function names.
269 set style variable foreground COLOR
270 set style variable background COLOR
271 set style variable intensity VALUE
272 Control the styling of variable names.
274 set style address foreground COLOR
275 set style address background COLOR
276 set style address intensity VALUE
277 Control the styling of addresses.
281 ** The default version of the MI interpreter is now 3 (-i=mi3).
283 ** The '-data-disassemble' MI command now accepts an '-a' option to
284 disassemble the whole function surrounding the given program
285 counter value or function name. Support for this feature can be
286 verified by using the "-list-features" command, which should
287 contain "data-disassemble-a-option".
289 ** Command responses and notifications that include a frame now include
290 the frame's architecture in a new "arch" attribute.
292 ** The output of information about multi-location breakpoints (which is
293 syntactically incorrect in MI 2) has changed in MI 3. This affects
294 the following commands and events:
298 - =breakpoint-created
299 - =breakpoint-modified
301 The -fix-multi-location-breakpoint-output command can be used to enable
302 this behavior with previous MI versions.
304 * New native configurations
306 GNU/Linux/RISC-V riscv*-*-linux*
307 FreeBSD/riscv riscv*-*-freebsd*
311 GNU/Linux/RISC-V riscv*-*-linux*
313 CSKY GNU/LINUX csky*-*-linux
314 FreeBSD/riscv riscv*-*-freebsd*
316 GNU/Linux/OpenRISC or1k*-*-linux*
320 GDB no longer supports native debugging on versions of MS-Windows
325 ** GDB no longer supports Python versions less than 2.6.
327 ** The gdb.Inferior type has a new 'progspace' property, which is the program
328 space associated to that inferior.
330 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
331 of objfiles associated to that program space.
333 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
334 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
337 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
338 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
339 correct and did not work properly.
341 ** The gdb.Value type has a new constructor, which is used to construct a
342 gdb.Value from a Python buffer object and a gdb.Type.
348 Enable or disable the undefined behavior sanitizer. This is
349 disabled by default, but passing --enable-ubsan=yes or
350 --enable-ubsan=auto to configure will enable it. Enabling this can
351 cause a performance penalty. The undefined behavior sanitizer was
352 first introduced in GCC 4.9.
354 *** Changes in GDB 8.2
356 * The 'set disassembler-options' command now supports specifying options
359 * The 'symbol-file' command now accepts an '-o' option to add a relative
360 offset to all sections.
362 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
363 a relative offset to all sections, but it allows to override the load
364 address of individual sections using '-s'.
366 * The 'add-symbol-file' command no longer requires the second argument
367 (address of the text section).
369 * The endianness used with the 'set endian auto' mode in the absence of
370 an executable selected for debugging is now the last endianness chosen
371 either by one of the 'set endian big' and 'set endian little' commands
372 or by inferring from the last executable used, rather than the startup
375 * The pager now allows a "c" response, meaning to disable the pager
376 for the rest of the current command.
378 * The commands 'info variables/functions/types' now show the source line
379 numbers of symbol definitions when available.
381 * 'info proc' now works on running processes on FreeBSD systems and core
382 files created on FreeBSD systems.
384 * C expressions can now use _Alignof, and C++ expressions can now use
387 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
388 the vector length while the process is running.
394 Control display of debugging info regarding the FreeBSD native target.
396 set|show varsize-limit
397 This new setting allows the user to control the maximum size of Ada
398 objects being printed when those objects have a variable type,
399 instead of that maximum size being hardcoded to 65536 bytes.
401 set|show record btrace cpu
402 Controls the processor to be used for enabling errata workarounds for
405 maint check libthread-db
406 Run integrity checks on the current inferior's thread debugging
409 maint set check-libthread-db (on|off)
410 maint show check-libthread-db
411 Control whether to run integrity checks on inferior specific thread
412 debugging libraries as they are loaded. The default is not to
417 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
419 ** The commands attached to a breakpoint can be set by assigning to
420 the breakpoint's "commands" field.
422 ** gdb.execute can now execute multi-line gdb commands.
424 ** The new functions gdb.convenience_variable and
425 gdb.set_convenience_variable can be used to get and set the value
426 of convenience variables.
428 ** A gdb.Parameter will no longer print the "set" help text on an
429 ordinary "set"; instead by default a "set" will be silent unless
430 the get_set_string method returns a non-empty string.
434 RiscV ELF riscv*-*-elf
436 * Removed targets and native configurations
438 m88k running OpenBSD m88*-*-openbsd*
439 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
440 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
441 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
443 * Aarch64/Linux hardware watchpoints improvements
445 Hardware watchpoints on unaligned addresses are now properly
446 supported when running Linux kernel 4.10 or higher: read and access
447 watchpoints are no longer spuriously missed, and all watchpoints
448 lengths between 1 and 8 bytes are supported. On older kernels,
449 watchpoints set on unaligned addresses are no longer missed, with
450 the tradeoff that there is a possibility of false hits being
455 --enable-codesign=CERT
456 This can be used to invoke "codesign -s CERT" after building gdb.
457 This option is useful on macOS, where code signing is required for
458 gdb to work properly.
460 --disable-gdbcli has been removed
461 This is now silently accepted, but does nothing.
463 *** Changes in GDB 8.1
465 * GDB now supports dynamically creating arbitrary register groups specified
466 in XML target descriptions. This allows for finer grain grouping of
467 registers on systems with a large amount of registers.
469 * The 'ptype' command now accepts a '/o' flag, which prints the
470 offsets and sizes of fields in a struct, like the pahole(1) tool.
472 * New "--readnever" command line option instructs GDB to not read each
473 symbol file's symbolic debug information. This makes startup faster
474 but at the expense of not being able to perform symbolic debugging.
475 This option is intended for use cases where symbolic debugging will
476 not be used, e.g., when you only need to dump the debuggee's core.
478 * GDB now uses the GNU MPFR library, if available, to emulate target
479 floating-point arithmetic during expression evaluation when the target
480 uses different floating-point formats than the host. At least version
481 3.1 of GNU MPFR is required.
483 * GDB now supports access to the guarded-storage-control registers and the
484 software-based guarded-storage broadcast control registers on IBM z14.
486 * On Unix systems, GDB now supports transmitting environment variables
487 that are to be set or unset to GDBserver. These variables will
488 affect the environment to be passed to the remote inferior.
490 To inform GDB of environment variables that are to be transmitted to
491 GDBserver, use the "set environment" command. Only user set
492 environment variables are sent to GDBserver.
494 To inform GDB of environment variables that are to be unset before
495 the remote inferior is started by the GDBserver, use the "unset
496 environment" command.
498 * Completion improvements
500 ** GDB can now complete function parameters in linespecs and
501 explicit locations without quoting. When setting breakpoints,
502 quoting around functions names to help with TAB-completion is
503 generally no longer necessary. For example, this now completes
506 (gdb) b function(in[TAB]
507 (gdb) b function(int)
509 Related, GDB is no longer confused with completing functions in
510 C++ anonymous namespaces:
513 (gdb) b (anonymous namespace)::[TAB][TAB]
514 (anonymous namespace)::a_function()
515 (anonymous namespace)::b_function()
517 ** GDB now has much improved linespec and explicit locations TAB
518 completion support, that better understands what you're
519 completing and offers better suggestions. For example, GDB no
520 longer offers data symbols as possible completions when you're
521 setting a breakpoint.
523 ** GDB now TAB-completes label symbol names.
525 ** The "complete" command now mimics TAB completion accurately.
527 * New command line options (gcore)
530 Dump all memory mappings.
532 * Breakpoints on C++ functions are now set on all scopes by default
534 By default, breakpoints on functions/methods are now interpreted as
535 specifying all functions with the given name ignoring missing
536 leading scopes (namespaces and classes).
538 For example, assuming a C++ program with symbols named:
543 both commands "break func()" and "break B::func()" set a breakpoint
546 You can use the new flag "-qualified" to override this. This makes
547 GDB interpret the specified function name as a complete
548 fully-qualified name instead. For example, using the same C++
549 program, the "break -q B::func" command sets a breakpoint on
550 "B::func", only. A parameter has been added to the Python
551 gdb.Breakpoint constructor to achieve the same result when creating
552 a breakpoint from Python.
554 * Breakpoints on functions marked with C++ ABI tags
556 GDB can now set breakpoints on functions marked with C++ ABI tags
557 (e.g., [abi:cxx11]). See here for a description of ABI tags:
558 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
560 Functions with a C++11 abi tag are demangled/displayed like this:
562 function[abi:cxx11](int)
565 You can now set a breakpoint on such functions simply as if they had
568 (gdb) b function(int)
570 Or if you need to disambiguate between tags, like:
572 (gdb) b function[abi:other_tag](int)
574 Tab completion was adjusted accordingly as well.
578 ** New events gdb.new_inferior, gdb.inferior_deleted, and
579 gdb.new_thread are emitted. See the manual for further
580 description of these.
582 ** A new function, "gdb.rbreak" has been added to the Python API.
583 This function allows the setting of a large number of breakpoints
584 via a regex pattern in Python. See the manual for further details.
586 ** Python breakpoints can now accept explicit locations. See the
587 manual for a further description of this feature.
590 * New features in the GDB remote stub, GDBserver
592 ** GDBserver is now able to start inferior processes with a
593 specified initial working directory.
595 The user can set the desired working directory to be used from
596 GDB using the new "set cwd" command.
598 ** New "--selftest" command line option runs some GDBserver self
599 tests. These self tests are disabled in releases.
601 ** On Unix systems, GDBserver now does globbing expansion and variable
602 substitution in inferior command line arguments.
604 This is done by starting inferiors using a shell, like GDB does.
605 See "set startup-with-shell" in the user manual for how to disable
606 this from GDB when using "target extended-remote". When using
607 "target remote", you can disable the startup with shell by using the
608 new "--no-startup-with-shell" GDBserver command line option.
610 ** On Unix systems, GDBserver now supports receiving environment
611 variables that are to be set or unset from GDB. These variables
612 will affect the environment to be passed to the inferior.
614 * When catching an Ada exception raised with a message, GDB now prints
615 the message in the catchpoint hit notification. In GDB/MI mode, that
616 information is provided as an extra field named "exception-message"
617 in the *stopped notification.
619 * Trait objects can now be inspected When debugging Rust code. This
620 requires compiler support which will appear in Rust 1.24.
624 QEnvironmentHexEncoded
625 Inform GDBserver of an environment variable that is to be passed to
626 the inferior when starting it.
629 Inform GDBserver of an environment variable that is to be unset
630 before starting the remote inferior.
633 Inform GDBserver that the environment should be reset (i.e.,
634 user-set environment variables should be unset).
637 Indicates whether the inferior must be started with a shell or not.
640 Tell GDBserver that the inferior to be started should use a specific
643 * The "maintenance print c-tdesc" command now takes an optional
644 argument which is the file name of XML target description.
646 * The "maintenance selftest" command now takes an optional argument to
647 filter the tests to be run.
649 * The "enable", and "disable" commands now accept a range of
650 breakpoint locations, e.g. "enable 1.3-5".
655 Set and show the current working directory for the inferior.
658 Set and show compilation command used for compiling and injecting code
659 with the 'compile' commands.
661 set debug separate-debug-file
662 show debug separate-debug-file
663 Control the display of debug output about separate debug file search.
665 set dump-excluded-mappings
666 show dump-excluded-mappings
667 Control whether mappings marked with the VM_DONTDUMP flag should be
668 dumped when generating a core file.
671 List the registered selftests.
674 Start the debugged program stopping at the first instruction.
677 Control display of debugging messages related to OpenRISC targets.
679 set|show print type nested-type-limit
680 Set and show the limit of nesting level for nested types that the
681 type printer will show.
683 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
686 * Safer/improved support for debugging with no debug info
688 GDB no longer assumes functions with no debug information return
691 This means that GDB now refuses to call such functions unless you
692 tell it the function's type, by either casting the call to the
693 declared return type, or by casting the function to a function
694 pointer of the right type, and calling that:
696 (gdb) p getenv ("PATH")
697 'getenv' has unknown return type; cast the call to its declared return type
698 (gdb) p (char *) getenv ("PATH")
699 $1 = 0x7fffffffe "/usr/local/bin:/"...
700 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
701 $2 = 0x7fffffffe "/usr/local/bin:/"...
703 Similarly, GDB no longer assumes that global variables with no debug
704 info have type 'int', and refuses to print the variable's value
705 unless you tell it the variable's type:
708 'var' has unknown type; cast it to its declared type
712 * New native configurations
714 FreeBSD/aarch64 aarch64*-*-freebsd*
715 FreeBSD/arm arm*-*-freebsd*
719 FreeBSD/aarch64 aarch64*-*-freebsd*
720 FreeBSD/arm arm*-*-freebsd*
721 OpenRISC ELF or1k*-*-elf
723 * Removed targets and native configurations
725 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
727 *** Changes in GDB 8.0
729 * GDB now supports access to the PKU register on GNU/Linux. The register is
730 added by the Memory Protection Keys for Userspace feature which will be
731 available in future Intel CPUs.
733 * GDB now supports C++11 rvalue references.
737 ** New functions to start, stop and access a running btrace recording.
738 ** Rvalue references are now supported in gdb.Type.
740 * GDB now supports recording and replaying rdrand and rdseed Intel 64
743 * Building GDB and GDBserver now requires a C++11 compiler.
745 For example, GCC 4.8 or later.
747 It is no longer possible to build GDB or GDBserver with a C
748 compiler. The --disable-build-with-cxx configure option has been
751 * Building GDB and GDBserver now requires GNU make >= 3.81.
753 It is no longer supported to build GDB or GDBserver with another
754 implementation of the make program or an earlier version of GNU make.
756 * Native debugging on MS-Windows supports command-line redirection
758 Command-line arguments used for starting programs on MS-Windows can
759 now include redirection symbols supported by native Windows shells,
760 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
761 as "run", "start", and "set args", as well as the corresponding MI
764 * Support for thread names on MS-Windows.
766 GDB now catches and handles the special exception that programs
767 running on MS-Windows use to assign names to threads in the
770 * Support for Java programs compiled with gcj has been removed.
772 * User commands now accept an unlimited number of arguments.
773 Previously, only up to 10 was accepted.
775 * The "eval" command now expands user-defined command arguments.
777 This makes it easier to process a variable number of arguments:
782 eval "print $arg%d", $i
787 * Target descriptions can now describe registers for sparc32 and sparc64.
789 * GDB now supports DWARF version 5 (debug information format).
790 Its .debug_names index is not yet supported.
792 * New native configurations
794 FreeBSD/mips mips*-*-freebsd
798 Synopsys ARC arc*-*-elf32
799 FreeBSD/mips mips*-*-freebsd
801 * Removed targets and native configurations
803 Alpha running FreeBSD alpha*-*-freebsd*
804 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
809 Erases all the flash memory regions reported by the target.
811 maint print arc arc-instruction address
812 Print internal disassembler information about instruction at a given address.
816 set disassembler-options
817 show disassembler-options
818 Controls the passing of target specific information to the disassembler.
819 If it is necessary to specify more than one disassembler option then
820 multiple options can be placed together into a comma separated list.
821 The default value is the empty string. Currently, the only supported
822 targets are ARM, PowerPC and S/390.
827 Erases all the flash memory regions reported by the target. This is
828 equivalent to the CLI command flash-erase.
830 -file-list-shared-libraries
831 List the shared libraries in the program. This is
832 equivalent to the CLI command "info shared".
835 Catchpoints stopping the program when Ada exceptions are
836 handled. This is equivalent to the CLI command "catch handlers".
838 *** Changes in GDB 7.12
840 * GDB and GDBserver now build with a C++ compiler by default.
842 The --enable-build-with-cxx configure option is now enabled by
843 default. One must now explicitly configure with
844 --disable-build-with-cxx in order to build with a C compiler. This
845 option will be removed in a future release.
847 * GDBserver now supports recording btrace without maintaining an active
850 * GDB now supports a negative repeat count in the 'x' command to examine
851 memory backward from the given address. For example:
854 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
855 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
856 (gdb) x/-5i 0x0000000000400580
857 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
858 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
859 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
860 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
861 0x40057b <main(int, char**)+25>:
862 callq 0x400536 <Func1(int, char const*)>
864 * Fortran: Support structures with fields of dynamic types and
865 arrays of dynamic types.
867 * The symbol dumping maintenance commands have new syntax.
868 maint print symbols [-pc address] [--] [filename]
869 maint print symbols [-objfile objfile] [-source source] [--] [filename]
870 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
871 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
872 maint print msymbols [-objfile objfile] [--] [filename]
874 * GDB now supports multibit bitfields and enums in target register
877 * New Python-based convenience function $_as_string(val), which returns
878 the textual representation of a value. This function is especially
879 useful to obtain the text label of an enum value.
881 * Intel MPX bound violation handling.
883 Segmentation faults caused by a Intel MPX boundary violation
884 now display the kind of violation (upper or lower), the memory
885 address accessed and the memory bounds, along with the usual
886 signal received and code location.
890 Program received signal SIGSEGV, Segmentation fault
891 Upper bound violation while accessing address 0x7fffffffc3b3
892 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
893 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
895 * Rust language support.
896 GDB now supports debugging programs written in the Rust programming
897 language. See https://www.rust-lang.org/ for more information about
900 * Support for running interpreters on specified input/output devices
902 GDB now supports a new mechanism that allows frontends to provide
903 fully featured GDB console views, as a better alternative to
904 building such views on top of the "-interpreter-exec console"
905 command. See the new "new-ui" command below. With that command,
906 frontends can now start GDB in the traditional command-line mode
907 running in an embedded terminal emulator widget, and create a
908 separate MI interpreter running on a specified i/o device. In this
909 way, GDB handles line editing, history, tab completion, etc. in the
910 console all by itself, and the GUI uses the separate MI interpreter
911 for its own control and synchronization, invisible to the command
914 * The "catch syscall" command catches groups of related syscalls.
916 The "catch syscall" command now supports catching a group of related
917 syscalls using the 'group:' or 'g:' prefix.
922 skip -gfile file-glob-pattern
923 skip -function function
924 skip -rfunction regular-expression
925 A generalized form of the skip command, with new support for
926 glob-style file names and regular expressions for function names.
927 Additionally, a file spec and a function spec may now be combined.
929 maint info line-table REGEXP
930 Display the contents of GDB's internal line table data struture.
933 Run any GDB unit tests that were compiled in.
936 Start a new user interface instance running INTERP as interpreter,
937 using the TTY file for input/output.
941 ** gdb.Breakpoint objects have a new attribute "pending", which
942 indicates whether the breakpoint is pending.
943 ** Three new breakpoint-related events have been added:
944 gdb.breakpoint_created, gdb.breakpoint_modified, and
945 gdb.breakpoint_deleted.
948 Signal ("set") the given MS-Windows event object. This is used in
949 conjunction with the Windows JIT debugging (AeDebug) support, where
950 the OS suspends a crashing process until a debugger can attach to
951 it. Resuming the crashing process, in order to debug it, is done by
954 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
955 was added in GDBserver, including JIT compiling fast tracepoint's
956 conditional expression bytecode into native code.
958 * Support for various remote target protocols and ROM monitors has
961 target m32rsdi Remote M32R debugging over SDI
962 target mips MIPS remote debugging protocol
963 target pmon PMON ROM monitor
964 target ddb NEC's DDB variant of PMON for Vr4300
965 target rockhopper NEC RockHopper variant of PMON
966 target lsi LSI variant of PMO
968 * Support for tracepoints and fast tracepoints on powerpc-linux,
969 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
970 including JIT compiling fast tracepoint's conditional expression
971 bytecode into native code.
973 * MI async record =record-started now includes the method and format used for
974 recording. For example:
976 =record-started,thread-group="i1",method="btrace",format="bts"
978 * MI async record =thread-selected now includes the frame field. For example:
980 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
984 Andes NDS32 nds32*-*-elf
986 *** Changes in GDB 7.11
988 * GDB now supports debugging kernel-based threads on FreeBSD.
990 * Per-inferior thread numbers
992 Thread numbers are now per inferior instead of global. If you're
993 debugging multiple inferiors, GDB displays thread IDs using a
994 qualified INF_NUM.THR_NUM form. For example:
998 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
999 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
1000 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
1001 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
1003 As consequence, thread numbers as visible in the $_thread
1004 convenience variable and in Python's InferiorThread.num attribute
1005 are no longer unique between inferiors.
1007 GDB now maintains a second thread ID per thread, referred to as the
1008 global thread ID, which is the new equivalent of thread numbers in
1009 previous releases. See also $_gthread below.
1011 For backwards compatibility, MI's thread IDs always refer to global
1014 * Commands that accept thread IDs now accept the qualified
1015 INF_NUM.THR_NUM form as well. For example:
1018 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
1021 * In commands that accept a list of thread IDs, you can now refer to
1022 all threads of an inferior using a star wildcard. GDB accepts
1023 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
1024 refer to all threads of the current inferior. For example, "info
1027 * You can use "info threads -gid" to display the global thread ID of
1030 * The new convenience variable $_gthread holds the global number of
1033 * The new convenience variable $_inferior holds the number of the
1036 * GDB now displays the ID and name of the thread that hit a breakpoint
1037 or received a signal, if your program is multi-threaded. For
1040 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
1041 Thread 1 "main" received signal SIGINT, Interrupt.
1043 * Record btrace now supports non-stop mode.
1045 * Support for tracepoints on aarch64-linux was added in GDBserver.
1047 * The 'record instruction-history' command now indicates speculative execution
1048 when using the Intel Processor Trace recording format.
1050 * GDB now allows users to specify explicit locations, bypassing
1051 the linespec parser. This feature is also available to GDB/MI
1054 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
1055 GDB now is able to debug both AArch64 applications and ARM applications
1058 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
1059 including JIT compiling fast tracepoint's conditional expression bytecode
1062 * GDB now supports displaced stepping on AArch64 GNU/Linux.
1064 * "info threads", "info inferiors", "info display", "info checkpoints"
1065 and "maint info program-spaces" now list the corresponding items in
1066 ascending ID order, for consistency with all other "info" commands.
1068 * In Ada, the overloads selection menu has been enhanced to display the
1069 parameter types and the return types for the matching overloaded subprograms.
1073 maint set target-non-stop (on|off|auto)
1074 maint show target-non-stop
1075 Control whether GDB targets always operate in non-stop mode even if
1076 "set non-stop" is "off". The default is "auto", meaning non-stop
1077 mode is enabled if supported by the target.
1079 maint set bfd-sharing
1080 maint show bfd-sharing
1081 Control the reuse of bfd objects.
1084 show debug bfd-cache
1085 Control display of debugging info regarding bfd caching.
1089 Control display of debugging info regarding FreeBSD threads.
1091 set remote multiprocess-extensions-packet
1092 show remote multiprocess-extensions-packet
1093 Set/show the use of the remote protocol multiprocess extensions.
1095 set remote thread-events
1096 show remote thread-events
1097 Set/show the use of thread create/exit events.
1099 set ada print-signatures on|off
1100 show ada print-signatures"
1101 Control whether parameter types and return types are displayed in overloads
1102 selection menus. It is activaled (@code{on}) by default.
1106 Controls the maximum size of memory, in bytes, that GDB will
1107 allocate for value contents. Prevents incorrect programs from
1108 causing GDB to allocate overly large buffers. Default is 64k.
1110 * The "disassemble" command accepts a new modifier: /s.
1111 It prints mixed source+disassembly like /m with two differences:
1112 - disassembled instructions are now printed in program order, and
1113 - and source for all relevant files is now printed.
1114 The "/m" option is now considered deprecated: its "source-centric"
1115 output hasn't proved useful in practice.
1117 * The "record instruction-history" command accepts a new modifier: /s.
1118 It behaves exactly like /m and prints mixed source+disassembly.
1120 * The "set scheduler-locking" command supports a new mode "replay".
1121 It behaves like "off" in record mode and like "on" in replay mode.
1123 * Support for various ROM monitors has been removed:
1125 target dbug dBUG ROM monitor for Motorola ColdFire
1126 target picobug Motorola picobug monitor
1127 target dink32 DINK32 ROM monitor for PowerPC
1128 target m32r Renesas M32R/D ROM monitor
1129 target mon2000 mon2000 ROM monitor
1130 target ppcbug PPCBUG ROM monitor for PowerPC
1132 * Support for reading/writing memory and extracting values on architectures
1133 whose memory is addressable in units of any integral multiple of 8 bits.
1136 Allows to break when an Ada exception is handled.
1138 * New remote packets
1141 Indicates that an exec system call was executed.
1143 exec-events feature in qSupported
1144 The qSupported packet allows GDB to request support for exec
1145 events using the new 'gdbfeature' exec-event, and the qSupported
1146 response can contain the corresponding 'stubfeature'. Set and
1147 show commands can be used to display whether these features are enabled.
1150 Equivalent to interrupting with the ^C character, but works in
1153 thread created stop reason (T05 create:...)
1154 Indicates that the thread was just created and is stopped at entry.
1156 thread exit stop reply (w exitcode;tid)
1157 Indicates that the thread has terminated.
1160 Enables/disables thread create and exit event reporting. For
1161 example, this is used in non-stop mode when GDB stops a set of
1162 threads and synchronously waits for the their corresponding stop
1163 replies. Without exit events, if one of the threads exits, GDB
1164 would hang forever not knowing that it should no longer expect a
1165 stop for that same thread.
1168 Indicates that there are no resumed threads left in the target (all
1169 threads are stopped). The remote stub reports support for this stop
1170 reply to GDB's qSupported query.
1173 Enables/disables catching syscalls from the inferior process.
1174 The remote stub reports support for this packet to GDB's qSupported query.
1176 syscall_entry stop reason
1177 Indicates that a syscall was just called.
1179 syscall_return stop reason
1180 Indicates that a syscall just returned.
1182 * Extended-remote exec events
1184 ** GDB now has support for exec events on extended-remote Linux targets.
1185 For such targets with Linux kernels 2.5.46 and later, this enables
1186 follow-exec-mode and exec catchpoints.
1188 set remote exec-event-feature-packet
1189 show remote exec-event-feature-packet
1190 Set/show the use of the remote exec event feature.
1192 * Thread names in remote protocol
1194 The reply to qXfer:threads:read may now include a name attribute for each
1197 * Target remote mode fork and exec events
1199 ** GDB now has support for fork and exec events on target remote mode
1200 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1201 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1202 fork and exec catchpoints.
1204 * Remote syscall events
1206 ** GDB now has support for catch syscall on remote Linux targets,
1207 currently enabled on x86/x86_64 architectures.
1209 set remote catch-syscall-packet
1210 show remote catch-syscall-packet
1211 Set/show the use of the remote catch syscall feature.
1215 ** The -var-set-format command now accepts the zero-hexadecimal
1216 format. It outputs data in hexadecimal format with zero-padding on the
1221 ** gdb.InferiorThread objects have a new attribute "global_num",
1222 which refers to the thread's global thread ID. The existing
1223 "num" attribute now refers to the thread's per-inferior number.
1224 See "Per-inferior thread numbers" above.
1225 ** gdb.InferiorThread objects have a new attribute "inferior", which
1226 is the Inferior object the thread belongs to.
1228 *** Changes in GDB 7.10
1230 * Support for process record-replay and reverse debugging on aarch64*-linux*
1231 targets has been added. GDB now supports recording of A64 instruction set
1232 including advance SIMD instructions.
1234 * Support for Sun's version of the "stabs" debug file format has been removed.
1236 * GDB now honors the content of the file /proc/PID/coredump_filter
1237 (PID is the process ID) on GNU/Linux systems. This file can be used
1238 to specify the types of memory mappings that will be included in a
1239 corefile. For more information, please refer to the manual page of
1240 "core(5)". GDB also has a new command: "set use-coredump-filter
1241 on|off". It allows to set whether GDB will read the content of the
1242 /proc/PID/coredump_filter file when generating a corefile.
1244 * The "info os" command on GNU/Linux can now display information on
1246 "info os cpus" Listing of all cpus/cores on the system
1248 * GDB has two new commands: "set serial parity odd|even|none" and
1249 "show serial parity". These allows to set or show parity for the
1252 * The "info source" command now displays the producer string if it was
1253 present in the debug info. This typically includes the compiler version
1254 and may include things like its command line arguments.
1256 * The "info dll", an alias of the "info sharedlibrary" command,
1257 is now available on all platforms.
1259 * Directory names supplied to the "set sysroot" commands may be
1260 prefixed with "target:" to tell GDB to access shared libraries from
1261 the target system, be it local or remote. This replaces the prefix
1262 "remote:". The default sysroot has been changed from "" to
1263 "target:". "remote:" is automatically converted to "target:" for
1264 backward compatibility.
1266 * The system root specified by "set sysroot" will be prepended to the
1267 filename of the main executable (if reported to GDB as absolute by
1268 the operating system) when starting processes remotely, and when
1269 attaching to already-running local or remote processes.
1271 * GDB now supports automatic location and retrieval of executable
1272 files from remote targets. Remote debugging can now be initiated
1273 using only a "target remote" or "target extended-remote" command
1274 (no "set sysroot" or "file" commands are required). See "New remote
1277 * The "dump" command now supports verilog hex format.
1279 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1281 * On GNU/Linux, GDB and gdbserver are now able to access executable
1282 and shared library files without a "set sysroot" command when
1283 attaching to processes running in different mount namespaces from
1284 the debugger. This makes it possible to attach to processes in
1285 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1286 See "New remote packets" below.
1288 * The "tui reg" command now provides completion for all of the
1289 available register groups, including target specific groups.
1291 * The HISTSIZE environment variable is no longer read when determining
1292 the size of GDB's command history. GDB now instead reads the dedicated
1293 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1294 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1299 ** Memory ports can now be unbuffered.
1303 ** gdb.Objfile objects have a new attribute "username",
1304 which is the name of the objfile as specified by the user,
1305 without, for example, resolving symlinks.
1306 ** You can now write frame unwinders in Python.
1307 ** gdb.Type objects have a new method "optimized_out",
1308 returning optimized out gdb.Value instance of this type.
1309 ** gdb.Value objects have new methods "reference_value" and
1310 "const_value" which return a reference to the value and a
1311 "const" version of the value respectively.
1315 maint print symbol-cache
1316 Print the contents of the symbol cache.
1318 maint print symbol-cache-statistics
1319 Print statistics of symbol cache usage.
1321 maint flush-symbol-cache
1322 Flush the contents of the symbol cache.
1326 Start branch trace recording using Branch Trace Store (BTS) format.
1329 Evaluate expression by using the compiler and print result.
1333 Explicit commands for enabling and disabling tui mode.
1336 set mpx bound on i386 and amd64
1337 Support for bound table investigation on Intel MPX enabled applications.
1341 Start branch trace recording using Intel Processor Trace format.
1344 Print information about branch tracing internals.
1346 maint btrace packet-history
1347 Print the raw branch tracing data.
1349 maint btrace clear-packet-history
1350 Discard the stored raw branch tracing data.
1353 Discard all branch tracing data. It will be fetched and processed
1354 anew by the next "record" command.
1359 Renamed from "set debug dwarf2-die".
1360 show debug dwarf-die
1361 Renamed from "show debug dwarf2-die".
1363 set debug dwarf-read
1364 Renamed from "set debug dwarf2-read".
1365 show debug dwarf-read
1366 Renamed from "show debug dwarf2-read".
1368 maint set dwarf always-disassemble
1369 Renamed from "maint set dwarf2 always-disassemble".
1370 maint show dwarf always-disassemble
1371 Renamed from "maint show dwarf2 always-disassemble".
1373 maint set dwarf max-cache-age
1374 Renamed from "maint set dwarf2 max-cache-age".
1375 maint show dwarf max-cache-age
1376 Renamed from "maint show dwarf2 max-cache-age".
1378 set debug dwarf-line
1379 show debug dwarf-line
1380 Control display of debugging info regarding DWARF line processing.
1383 show max-completions
1384 Set the maximum number of candidates to be considered during
1385 completion. The default value is 200. This limit allows GDB
1386 to avoid generating large completion lists, the computation of
1387 which can cause the debugger to become temporarily unresponsive.
1389 set history remove-duplicates
1390 show history remove-duplicates
1391 Control the removal of duplicate history entries.
1393 maint set symbol-cache-size
1394 maint show symbol-cache-size
1395 Control the size of the symbol cache.
1397 set|show record btrace bts buffer-size
1398 Set and show the size of the ring buffer used for branch tracing in
1400 The obtained size may differ from the requested size. Use "info
1401 record" to see the obtained buffer size.
1403 set debug linux-namespaces
1404 show debug linux-namespaces
1405 Control display of debugging info regarding Linux namespaces.
1407 set|show record btrace pt buffer-size
1408 Set and show the size of the ring buffer used for branch tracing in
1409 Intel Processor Trace format.
1410 The obtained size may differ from the requested size. Use "info
1411 record" to see the obtained buffer size.
1413 maint set|show btrace pt skip-pad
1414 Set and show whether PAD packets are skipped when computing the
1417 * The command 'thread apply all' can now support new option '-ascending'
1418 to call its specified command for all threads in ascending order.
1420 * Python/Guile scripting
1422 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1423 special section named `.debug_gdb_scripts'.
1425 * New remote packets
1427 qXfer:btrace-conf:read
1428 Return the branch trace configuration for the current thread.
1430 Qbtrace-conf:bts:size
1431 Set the requested ring buffer size for branch tracing in BTS format.
1434 Enable Intel Procesor Trace-based branch tracing for the current
1435 process. The remote stub reports support for this packet to GDB's
1438 Qbtrace-conf:pt:size
1439 Set the requested ring buffer size for branch tracing in Intel Processor
1443 Indicates a memory breakpoint instruction was executed, irrespective
1444 of whether it was GDB that planted the breakpoint or the breakpoint
1445 is hardcoded in the program. This is required for correct non-stop
1449 Indicates the target stopped for a hardware breakpoint. This is
1450 required for correct non-stop mode operation.
1453 Return information about files on the remote system.
1455 qXfer:exec-file:read
1456 Return the full absolute name of the file that was executed to
1457 create a process running on the remote system.
1460 Select the filesystem on which vFile: operations with filename
1461 arguments will operate. This is required for GDB to be able to
1462 access files on remote targets where the remote stub does not
1463 share a common filesystem with the inferior(s).
1466 Indicates that a fork system call was executed.
1469 Indicates that a vfork system call was executed.
1471 vforkdone stop reason
1472 Indicates that a vfork child of the specified process has executed
1473 an exec or exit, allowing the vfork parent to resume execution.
1475 fork-events and vfork-events features in qSupported
1476 The qSupported packet allows GDB to request support for fork and
1477 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1478 and the qSupported response can contain the corresponding
1479 'stubfeatures'. Set and show commands can be used to display
1480 whether these features are enabled.
1482 * Extended-remote fork events
1484 ** GDB now has support for fork events on extended-remote Linux
1485 targets. For targets with Linux kernels 2.5.60 and later, this
1486 enables follow-fork-mode and detach-on-fork for both fork and
1487 vfork, as well as fork and vfork catchpoints.
1489 * The info record command now shows the recording format and the
1490 branch tracing configuration for the current thread when using
1491 the btrace record target.
1492 For the BTS format, it shows the ring buffer size.
1494 * GDB now has support for DTrace USDT (Userland Static Defined
1495 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1497 * GDB now supports access to vector registers on S/390 GNU/Linux
1500 * Removed command line options
1502 -xdb HP-UX XDB compatibility mode.
1504 * Removed targets and native configurations
1506 HP/PA running HP-UX hppa*-*-hpux*
1507 Itanium running HP-UX ia64-*-hpux*
1509 * New configure options
1512 This configure option allows the user to build GDB with support for
1513 Intel Processor Trace (default: auto). This requires libipt.
1515 --with-libipt-prefix=PATH
1516 Specify the path to the version of libipt that GDB should use.
1517 $PATH/include should contain the intel-pt.h header and
1518 $PATH/lib should contain the libipt.so library.
1520 *** Changes in GDB 7.9.1
1524 ** Xmethods can now specify a result type.
1526 *** Changes in GDB 7.9
1528 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1532 ** You can now access frame registers from Python scripts.
1533 ** New attribute 'producer' for gdb.Symtab objects.
1534 ** gdb.Objfile objects have a new attribute "progspace",
1535 which is the gdb.Progspace object of the containing program space.
1536 ** gdb.Objfile objects have a new attribute "owner".
1537 ** gdb.Objfile objects have a new attribute "build_id",
1538 which is the build ID generated when the file was built.
1539 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1540 ** A new event "gdb.clear_objfiles" has been added, triggered when
1541 selecting a new file to debug.
1542 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1543 ** New function gdb.lookup_objfile.
1545 New events which are triggered when GDB modifies the state of the
1548 ** gdb.events.inferior_call_pre: Function call is about to be made.
1549 ** gdb.events.inferior_call_post: Function call has just been made.
1550 ** gdb.events.memory_changed: A memory location has been altered.
1551 ** gdb.events.register_changed: A register has been altered.
1553 * New Python-based convenience functions:
1555 ** $_caller_is(name [, number_of_frames])
1556 ** $_caller_matches(regexp [, number_of_frames])
1557 ** $_any_caller_is(name [, number_of_frames])
1558 ** $_any_caller_matches(regexp [, number_of_frames])
1560 * GDB now supports the compilation and injection of source code into
1561 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1562 to compile the source code to object code, and if successful, inject
1563 and execute that code within the current context of the inferior.
1564 Currently the C language is supported. The commands used to
1565 interface with this new feature are:
1567 compile code [-raw|-r] [--] [source code]
1568 compile file [-raw|-r] filename
1572 demangle [-l language] [--] name
1573 Demangle "name" in the specified language, or the current language
1574 if elided. This command is renamed from the "maint demangle" command.
1575 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1576 as "maint demangler-warning".
1578 queue-signal signal-name-or-number
1579 Queue a signal to be delivered to the thread when it is resumed.
1581 add-auto-load-scripts-directory directory
1582 Add entries to the list of directories from which to load auto-loaded
1585 maint print user-registers
1586 List all currently available "user" registers.
1588 compile code [-r|-raw] [--] [source code]
1589 Compile, inject, and execute in the inferior the executable object
1590 code produced by compiling the provided source code.
1592 compile file [-r|-raw] filename
1593 Compile and inject into the inferior the executable object code
1594 produced by compiling the source code stored in the filename
1597 * On resume, GDB now always passes the signal the program had stopped
1598 for to the thread the signal was sent to, even if the user changed
1599 threads before resuming. Previously GDB would often (but not
1600 always) deliver the signal to the thread that happens to be current
1603 * Conversely, the "signal" command now consistently delivers the
1604 requested signal to the current thread. GDB now asks for
1605 confirmation if the program had stopped for a signal and the user
1606 switched threads meanwhile.
1608 * "breakpoint always-inserted" modes "off" and "auto" merged.
1610 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1611 won't remove breakpoints from the target until all threads stop,
1612 even in non-stop mode. The "auto" mode has been removed, and "off"
1613 is now the default mode.
1617 set debug symbol-lookup
1618 show debug symbol-lookup
1619 Control display of debugging info regarding symbol lookup.
1623 ** The -list-thread-groups command outputs an exit-code field for
1624 inferiors that have exited.
1628 MIPS SDE mips*-sde*-elf*
1632 Support for these obsolete configurations has been removed.
1634 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1635 SGI Irix-5.x mips-*-irix5*
1636 SGI Irix-6.x mips-*-irix6*
1637 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1638 VAX running Ultrix vax-*-ultrix*
1640 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1641 and "assf"), have been removed. Use the "sharedlibrary" command, or
1642 its alias "share", instead.
1644 *** Changes in GDB 7.8
1646 * New command line options
1649 This is an alias for the --data-directory option.
1651 * GDB supports printing and modifying of variable length automatic arrays
1652 as specified in ISO C99.
1654 * The ARM simulator now supports instruction level tracing
1655 with or without disassembly.
1659 GDB now has support for scripting using Guile. Whether this is
1660 available is determined at configure time.
1661 Guile version 2.0 or greater is required.
1662 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1664 * New commands (for set/show, see "New options" below)
1668 Invoke CODE by passing it to the Guile interpreter.
1672 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1674 info auto-load guile-scripts [regexp]
1675 Print the list of automatically loaded Guile scripts.
1677 * The source command is now capable of sourcing Guile scripts.
1678 This feature is dependent on the debugger being built with Guile support.
1682 set print symbol-loading (off|brief|full)
1683 show print symbol-loading
1684 Control whether to print informational messages when loading symbol
1685 information for a file. The default is "full", but when debugging
1686 programs with large numbers of shared libraries the amount of output
1687 becomes less useful.
1689 set guile print-stack (none|message|full)
1690 show guile print-stack
1691 Show a stack trace when an error is encountered in a Guile script.
1693 set auto-load guile-scripts (on|off)
1694 show auto-load guile-scripts
1695 Control auto-loading of Guile script files.
1697 maint ada set ignore-descriptive-types (on|off)
1698 maint ada show ignore-descriptive-types
1699 Control whether the debugger should ignore descriptive types in Ada
1700 programs. The default is not to ignore the descriptive types. See
1701 the user manual for more details on descriptive types and the intended
1702 usage of this option.
1704 set auto-connect-native-target
1706 Control whether GDB is allowed to automatically connect to the
1707 native target for the run, attach, etc. commands when not connected
1708 to any target yet. See also "target native" below.
1710 set record btrace replay-memory-access (read-only|read-write)
1711 show record btrace replay-memory-access
1712 Control what memory accesses are allowed during replay.
1714 maint set target-async (on|off)
1715 maint show target-async
1716 This controls whether GDB targets operate in synchronous or
1717 asynchronous mode. Normally the default is asynchronous, if it is
1718 available; but this can be changed to more easily debug problems
1719 occurring only in synchronous mode.
1721 set mi-async (on|off)
1723 Control whether MI asynchronous mode is preferred. This supersedes
1724 "set target-async" of previous GDB versions.
1726 * "set target-async" is deprecated as a CLI option and is now an alias
1727 for "set mi-async" (only puts MI into async mode).
1729 * Background execution commands (e.g., "c&", "s&", etc.) are now
1730 possible ``out of the box'' if the target supports them. Previously
1731 the user would need to explicitly enable the possibility with the
1732 "set target-async on" command.
1734 * New features in the GDB remote stub, GDBserver
1736 ** New option --debug-format=option1[,option2,...] allows one to add
1737 additional text to each output. At present only timestamps
1738 are supported: --debug-format=timestamps.
1739 Timestamps can also be turned on with the
1740 "monitor set debug-format timestamps" command from GDB.
1742 * The 'record instruction-history' command now starts counting instructions
1743 at one. This also affects the instruction ranges reported by the
1744 'record function-call-history' command when given the /i modifier.
1746 * The command 'record function-call-history' supports a new modifier '/c' to
1747 indent the function names based on their call stack depth.
1748 The fields for the '/i' and '/l' modifier have been reordered.
1749 The source line range is now prefixed with 'at'.
1750 The instruction range is now prefixed with 'inst'.
1751 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1752 "record instruction-history" and "list" commands.
1754 * The ranges given as arguments to the 'record function-call-history' and
1755 'record instruction-history' commands are now inclusive.
1757 * The btrace record target now supports the 'record goto' command.
1758 For locations inside the execution trace, the back trace is computed
1759 based on the information stored in the execution trace.
1761 * The btrace record target supports limited reverse execution and replay.
1762 The target does not record data and therefore does not allow reading
1763 memory or registers.
1765 * The "catch syscall" command now works on s390*-linux* targets.
1767 * The "compare-sections" command is no longer specific to target
1768 remote. It now works with all targets.
1770 * All native targets are now consistently called "native".
1771 Consequently, the "target child", "target GNU", "target djgpp",
1772 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1773 commands have been replaced with "target native". The QNX/NTO port
1774 leaves the "procfs" target in place and adds a "native" target for
1775 consistency with other ports. The impact on users should be minimal
1776 as these commands previously either throwed an error, or were
1777 no-ops. The target's name is visible in the output of the following
1778 commands: "help target", "info target", "info files", "maint print
1781 * The "target native" command now connects to the native target. This
1782 can be used to launch native programs even when "set
1783 auto-connect-native-target" is set to off.
1785 * GDB now supports access to Intel MPX registers on GNU/Linux.
1787 * Support for Intel AVX-512 registers on GNU/Linux.
1788 Support displaying and modifying Intel AVX-512 registers
1789 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1791 * New remote packets
1793 qXfer:btrace:read's annex
1794 The qXfer:btrace:read packet supports a new annex 'delta' to read
1795 branch trace incrementally.
1799 ** Valid Python operations on gdb.Value objects representing
1800 structs/classes invoke the corresponding overloaded operators if
1802 ** New `Xmethods' feature in the Python API. Xmethods are
1803 additional methods or replacements for existing methods of a C++
1804 class. This feature is useful for those cases where a method
1805 defined in C++ source code could be inlined or optimized out by
1806 the compiler, making it unavailable to GDB.
1809 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1811 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1812 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1813 its alias "share", instead.
1815 * The commands "set remotebaud" and "show remotebaud" are no longer
1816 supported. Use "set serial baud" and "show serial baud" (respectively)
1821 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1822 target-async". The latter is left as a deprecated alias of the
1823 former for backward compatibility. If the target supports it,
1824 CLI background execution commands are now always possible by
1825 default, independently of whether the frontend stated a
1826 preference for asynchronous execution with "-gdb-set mi-async".
1827 Previously "-gdb-set target-async off" affected both MI execution
1828 commands and CLI execution commands.
1830 *** Changes in GDB 7.7
1832 * Improved support for process record-replay and reverse debugging on
1833 arm*-linux* targets. Support for thumb32 and syscall instruction
1834 recording has been added.
1836 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1838 * GDB now supports Fission DWP file format version 2.
1839 http://gcc.gnu.org/wiki/DebugFission
1841 * New convenience function "$_isvoid", to check whether an expression
1842 is void. A void expression is an expression where the type of the
1843 result is "void". For example, some convenience variables may be
1844 "void" when evaluated (e.g., "$_exitcode" before the execution of
1845 the program being debugged; or an undefined convenience variable).
1846 Another example, when calling a function whose return type is
1849 * The "maintenance print objfiles" command now takes an optional regexp.
1851 * The "catch syscall" command now works on arm*-linux* targets.
1853 * GDB now consistently shows "<not saved>" when printing values of
1854 registers the debug info indicates have not been saved in the frame
1855 and there's nowhere to retrieve them from
1856 (callee-saved/call-clobbered registers):
1861 (gdb) info registers rax
1864 Before, the former would print "<optimized out>", and the latter
1865 "*value not available*".
1867 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1872 ** Frame filters and frame decorators have been added.
1873 ** Temporary breakpoints are now supported.
1874 ** Line tables representation has been added.
1875 ** New attribute 'parent_type' for gdb.Field objects.
1876 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1877 ** New attribute 'name' for gdb.Type objects.
1881 Nios II ELF nios2*-*-elf
1882 Nios II GNU/Linux nios2*-*-linux
1883 Texas Instruments MSP430 msp430*-*-elf
1885 * Removed native configurations
1887 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1888 been removed. ELF variants of these configurations are kept supported.
1890 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1891 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1892 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1893 i[34567]86-*-openbsd3.[0-3]
1894 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1895 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1896 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1900 Like "catch throw", but catches a re-thrown exception.
1901 maint check-psymtabs
1902 Renamed from old "maint check-symtabs".
1904 Perform consistency checks on symtabs.
1905 maint expand-symtabs
1906 Expand symtabs matching an optional regexp.
1909 Display the details of GDB configure-time options.
1911 maint set|show per-command
1912 maint set|show per-command space
1913 maint set|show per-command time
1914 maint set|show per-command symtab
1915 Enable display of per-command gdb resource usage.
1917 remove-symbol-file FILENAME
1918 remove-symbol-file -a ADDRESS
1919 Remove a symbol file added via add-symbol-file. The file to remove
1920 can be identified by its filename or by an address that lies within
1921 the boundaries of this symbol file in memory.
1924 info exceptions REGEXP
1925 Display the list of Ada exceptions defined in the program being
1926 debugged. If provided, only the exceptions whose names match REGEXP
1931 set debug symfile off|on
1933 Control display of debugging info regarding reading symbol files and
1934 symbol tables within those files
1936 set print raw frame-arguments
1937 show print raw frame-arguments
1938 Set/show whether to print frame arguments in raw mode,
1939 disregarding any defined pretty-printers.
1941 set remote trace-status-packet
1942 show remote trace-status-packet
1943 Set/show the use of remote protocol qTStatus packet.
1947 Control display of debugging messages related to Nios II targets.
1951 Control whether target-assisted range stepping is enabled.
1953 set startup-with-shell
1954 show startup-with-shell
1955 Specifies whether Unix child processes are started via a shell or
1960 Use the target memory cache for accesses to the code segment. This
1961 improves performance of remote debugging (particularly disassembly).
1963 * You can now use a literal value 'unlimited' for options that
1964 interpret 0 or -1 as meaning "unlimited". E.g., "set
1965 trace-buffer-size unlimited" is now an alias for "set
1966 trace-buffer-size -1" and "set height unlimited" is now an alias for
1969 * The "set debug symtab-create" debugging option of GDB has been changed to
1970 accept a verbosity level. 0 means "off", 1 provides basic debugging
1971 output, and values of 2 or greater provides more verbose output.
1973 * New command-line options
1975 Display the details of GDB configure-time options.
1977 * The command 'tsave' can now support new option '-ctf' to save trace
1978 buffer in Common Trace Format.
1980 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1983 * GDB now implements the the C++ 'typeid' operator.
1985 * The new convenience variable $_exception holds the exception being
1986 thrown or caught at an exception-related catchpoint.
1988 * The exception-related catchpoints, like "catch throw", now accept a
1989 regular expression which can be used to filter exceptions by type.
1991 * The new convenience variable $_exitsignal is automatically set to
1992 the terminating signal number when the program being debugged dies
1993 due to an uncaught signal.
1997 ** All MI commands now accept an optional "--language" option.
1998 Support for this feature can be verified by using the "-list-features"
1999 command, which should contain "language-option".
2001 ** The new command -info-gdb-mi-command allows the user to determine
2002 whether a GDB/MI command is supported or not.
2004 ** The "^error" result record returned when trying to execute an undefined
2005 GDB/MI command now provides a variable named "code" whose content is the
2006 "undefined-command" error code. Support for this feature can be verified
2007 by using the "-list-features" command, which should contain
2008 "undefined-command-error-code".
2010 ** The -trace-save MI command can optionally save trace buffer in Common
2013 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
2015 ** The command -data-list-register-values now accepts an optional
2016 "--skip-unavailable" option. When used, only the available registers
2019 ** The new command -trace-frame-collected dumps collected variables,
2020 computed expressions, tvars, memory and registers in a traceframe.
2022 ** The commands -stack-list-locals, -stack-list-arguments and
2023 -stack-list-variables now accept an option "--skip-unavailable".
2024 When used, only the available locals or arguments are displayed.
2026 ** The -exec-run command now accepts an optional "--start" option.
2027 When used, the command follows the same semantics as the "start"
2028 command, stopping the program's execution at the start of its
2029 main subprogram. Support for this feature can be verified using
2030 the "-list-features" command, which should contain
2031 "exec-run-start-option".
2033 ** The new commands -catch-assert and -catch-exceptions insert
2034 catchpoints stopping the program when Ada exceptions are raised.
2036 ** The new command -info-ada-exceptions provides the equivalent of
2037 the new "info exceptions" command.
2039 * New system-wide configuration scripts
2040 A GDB installation now provides scripts suitable for use as system-wide
2041 configuration scripts for the following systems:
2045 * GDB now supports target-assigned range stepping with remote targets.
2046 This improves the performance of stepping source lines by reducing
2047 the number of control packets from/to GDB. See "New remote packets"
2050 * GDB now understands the element 'tvar' in the XML traceframe info.
2051 It has the id of the collected trace state variables.
2053 * On S/390 targets that provide the transactional-execution feature,
2054 the program interruption transaction diagnostic block (TDB) is now
2055 represented as a number of additional "registers" in GDB.
2057 * New remote packets
2061 The vCont packet supports a new 'r' action, that tells the remote
2062 stub to step through an address range itself, without GDB
2063 involvemement at each single-step.
2065 qXfer:libraries-svr4:read's annex
2066 The previously unused annex of the qXfer:libraries-svr4:read packet
2067 is now used to support passing an argument list. The remote stub
2068 reports support for this argument list to GDB's qSupported query.
2069 The defined arguments are "start" and "prev", used to reduce work
2070 necessary for library list updating, resulting in significant
2073 * New features in the GDB remote stub, GDBserver
2075 ** GDBserver now supports target-assisted range stepping. Currently
2076 enabled on x86/x86_64 GNU/Linux targets.
2078 ** GDBserver now adds element 'tvar' in the XML in the reply to
2079 'qXfer:traceframe-info:read'. It has the id of the collected
2080 trace state variables.
2082 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
2085 * New 'z' formatter for printing and examining memory, this displays the
2086 value as hexadecimal zero padded on the left to the size of the type.
2088 * GDB can now use Windows x64 unwinding data.
2090 * The "set remotebaud" command has been replaced by "set serial baud".
2091 Similarly, "show remotebaud" has been replaced by "show serial baud".
2092 The "set remotebaud" and "show remotebaud" commands are still available
2093 to provide backward compatibility with older versions of GDB.
2095 *** Changes in GDB 7.6
2097 * Target record has been renamed to record-full.
2098 Record/replay is now enabled with the "record full" command.
2099 This also affects settings that are associated with full record/replay
2100 that have been moved from "set/show record" to "set/show record full":
2102 set|show record full insn-number-max
2103 set|show record full stop-at-limit
2104 set|show record full memory-query
2106 * A new record target "record-btrace" has been added. The new target
2107 uses hardware support to record the control-flow of a process. It
2108 does not support replaying the execution, but it implements the
2109 below new commands for investigating the recorded execution log.
2110 This new recording method can be enabled using:
2114 The "record-btrace" target is only available on Intel Atom processors
2115 and requires a Linux kernel 2.6.32 or later.
2117 * Two new commands have been added for record/replay to give information
2118 about the recorded execution without having to replay the execution.
2119 The commands are only supported by "record btrace".
2121 record instruction-history prints the execution history at
2122 instruction granularity
2124 record function-call-history prints the execution history at
2125 function granularity
2127 * New native configurations
2129 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2130 FreeBSD/powerpc powerpc*-*-freebsd
2131 x86_64/Cygwin x86_64-*-cygwin*
2132 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2136 ARM AArch64 aarch64*-*-elf
2137 ARM AArch64 GNU/Linux aarch64*-*-linux
2138 Lynx 178 PowerPC powerpc-*-lynx*178
2139 x86_64/Cygwin x86_64-*-cygwin*
2140 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2142 * If the configured location of system.gdbinit file (as given by the
2143 --with-system-gdbinit option at configure time) is in the
2144 data-directory (as specified by --with-gdb-datadir at configure
2145 time) or in one of its subdirectories, then GDB will look for the
2146 system-wide init file in the directory specified by the
2147 --data-directory command-line option.
2149 * New command line options:
2151 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2152 other initialization files, unlike -nx which disables all of them.
2154 * Removed command line options
2156 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2159 * The 'ptype' and 'whatis' commands now accept an argument to control
2162 * 'info proc' now works on some core files.
2166 ** Vectors can be created with gdb.Type.vector.
2168 ** Python's atexit.register now works in GDB.
2170 ** Types can be pretty-printed via a Python API.
2172 ** Python 3 is now supported (in addition to Python 2.4 or later)
2174 ** New class gdb.Architecture exposes GDB's internal representation
2175 of architecture in the Python API.
2177 ** New method Frame.architecture returns the gdb.Architecture object
2178 corresponding to the frame's architecture.
2180 * New Python-based convenience functions:
2182 ** $_memeq(buf1, buf2, length)
2183 ** $_streq(str1, str2)
2185 ** $_regex(str, regex)
2187 * The 'cd' command now defaults to using '~' (the home directory) if not
2190 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2191 default for GCC since November 2000.
2193 * The command 'forward-search' can now be abbreviated as 'fo'.
2195 * The command 'info tracepoints' can now display 'installed on target'
2196 or 'not installed on target' for each non-pending location of tracepoint.
2198 * New configure options
2200 --enable-libmcheck/--disable-libmcheck
2201 By default, development versions are built with -lmcheck on hosts
2202 that support it, in order to help track memory corruption issues.
2203 Release versions, on the other hand, are built without -lmcheck
2204 by default. The --enable-libmcheck/--disable-libmcheck configure
2205 options allow the user to override that default.
2206 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2207 This configure option allows the user to build GDB with
2208 libbabeltrace using which GDB can read Common Trace Format data.
2210 * New commands (for set/show, see "New options" below)
2213 Catch signals. This is similar to "handle", but allows commands and
2214 conditions to be attached.
2217 List the BFDs known to GDB.
2219 python-interactive [command]
2221 Start a Python interactive prompt, or evaluate the optional command
2222 and print the result of expressions.
2225 "py" is a new alias for "python".
2227 enable type-printer [name]...
2228 disable type-printer [name]...
2229 Enable or disable type printers.
2233 ** For the Renesas Super-H architecture, the "regs" command has been removed
2234 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2239 set print type methods (on|off)
2240 show print type methods
2241 Control whether method declarations are displayed by "ptype".
2242 The default is to show them.
2244 set print type typedefs (on|off)
2245 show print type typedefs
2246 Control whether typedef definitions are displayed by "ptype".
2247 The default is to show them.
2249 set filename-display basename|relative|absolute
2250 show filename-display
2251 Control the way in which filenames is displayed.
2252 The default is "relative", which preserves previous behavior.
2254 set trace-buffer-size
2255 show trace-buffer-size
2256 Request target to change the size of trace buffer.
2258 set remote trace-buffer-size-packet auto|on|off
2259 show remote trace-buffer-size-packet
2260 Control the use of the remote protocol `QTBuffer:size' packet.
2264 Control display of debugging messages related to ARM AArch64.
2267 set debug coff-pe-read
2268 show debug coff-pe-read
2269 Control display of debugging messages related to reading of COFF/PE
2274 Control display of debugging messages related to Mach-O symbols
2277 set debug notification
2278 show debug notification
2279 Control display of debugging info for async remote notification.
2283 ** Command parameter changes are now notified using new async record
2284 "=cmd-param-changed".
2285 ** Trace frame changes caused by command "tfind" are now notified using
2286 new async record "=traceframe-changed".
2287 ** The creation, deletion and modification of trace state variables
2288 are now notified using new async records "=tsv-created",
2289 "=tsv-deleted" and "=tsv-modified".
2290 ** The start and stop of process record are now notified using new
2291 async record "=record-started" and "=record-stopped".
2292 ** Memory changes are now notified using new async record
2294 ** The data-disassemble command response will include a "fullname" field
2295 containing the absolute file name when source has been requested.
2296 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2297 command, to allow pattern filling of memory areas.
2298 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2299 library load/unload events.
2300 ** The response to breakpoint commands and breakpoint async records
2301 includes an "installed" field containing a boolean state about each
2302 non-pending tracepoint location is whether installed on target or not.
2303 ** Output of the "-trace-status" command includes a "trace-file" field
2304 containing the name of the trace file being examined. This field is
2305 optional, and only present when examining a trace file.
2306 ** The "fullname" field is now always present along with the "file" field,
2307 even if the file cannot be found by GDB.
2309 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2310 You must have the LZMA library available when configuring GDB for this
2311 feature to be enabled. For more information, see:
2312 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2314 * New remote packets
2317 Set the size of trace buffer. The remote stub reports support for this
2318 packet to gdb's qSupported query.
2321 Enable Branch Trace Store (BTS)-based branch tracing for the current
2322 thread. The remote stub reports support for this packet to gdb's
2326 Disable branch tracing for the current thread. The remote stub reports
2327 support for this packet to gdb's qSupported query.
2330 Read the traced branches for the current thread. The remote stub
2331 reports support for this packet to gdb's qSupported query.
2333 *** Changes in GDB 7.5
2335 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2336 for more x32 ABI info.
2338 * GDB now supports access to MIPS DSP registers on Linux targets.
2340 * GDB now supports debugging microMIPS binaries.
2342 * The "info os" command on GNU/Linux can now display information on
2343 several new classes of objects managed by the operating system:
2344 "info os procgroups" lists process groups
2345 "info os files" lists file descriptors
2346 "info os sockets" lists internet-domain sockets
2347 "info os shm" lists shared-memory regions
2348 "info os semaphores" lists semaphores
2349 "info os msg" lists message queues
2350 "info os modules" lists loaded kernel modules
2352 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2353 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2354 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2355 options and inspect the probe arguments using the new $_probe_arg family
2356 of convenience variables. You can obtain more information about SystemTap
2357 in <http://sourceware.org/systemtap/>.
2359 * GDB now supports reversible debugging on ARM, it allows you to
2360 debug basic ARM and THUMB instructions, and provides
2361 record/replay support.
2363 * The option "symbol-reloading" has been deleted as it is no longer used.
2367 ** GDB commands implemented in Python can now be put in command class
2370 ** The "maint set python print-stack on|off" is now deleted.
2372 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2373 apply "flag enum"-style pretty-printing to any enum.
2375 ** gdb.lookup_symbol can now work when there is no current frame.
2377 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2378 the source at which the symbol was defined.
2380 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2381 method 'value'. The former indicates whether the symbol needs a
2382 frame in order to compute its value, and the latter computes the
2385 ** A new method 'referenced_value' on gdb.Value objects which can
2386 dereference pointer as well as C++ reference values.
2388 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2389 which return the global and static blocks (as gdb.Block objects),
2390 of the underlying symbol table, respectively.
2392 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2393 object associated with a PC value.
2395 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2396 of the address range occupied by code for the current source line.
2398 * Go language support.
2399 GDB now supports debugging programs written in the Go programming
2402 * GDBserver now supports stdio connections.
2403 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2405 * The binary "gdbtui" can no longer be built or installed.
2406 Use "gdb -tui" instead.
2408 * GDB will now print "flag" enums specially. A flag enum is one where
2409 all the enumerator values have no bits in common when pairwise
2410 "and"ed. When printing a value whose type is a flag enum, GDB will
2411 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2412 (gdb) print (enum E) 3
2415 * The filename part of a linespec will now match trailing components
2416 of a source file name. For example, "break gcc/expr.c:1000" will
2417 now set a breakpoint in build/gcc/expr.c, but not
2418 build/libcpp/expr.c.
2420 * The "info proc" and "generate-core-file" commands will now also
2421 work on remote targets connected to GDBserver on Linux.
2423 * The command "info catch" has been removed. It has been disabled
2424 since December 2007.
2426 * The "catch exception" and "catch assert" commands now accept
2427 a condition at the end of the command, much like the "break"
2428 command does. For instance:
2430 (gdb) catch exception Constraint_Error if Barrier = True
2432 Previously, it was possible to add a condition to such catchpoints,
2433 but it had to be done as a second step, after the catchpoint had been
2434 created, using the "condition" command.
2436 * The "info static-tracepoint-marker" command will now also work on
2437 native Linux targets with in-process agent.
2439 * GDB can now set breakpoints on inlined functions.
2441 * The .gdb_index section has been updated to include symbols for
2442 inlined functions. GDB will ignore older .gdb_index sections by
2443 default, which could cause symbol files to be loaded more slowly
2444 until their .gdb_index sections can be recreated. The new command
2445 "set use-deprecated-index-sections on" will cause GDB to use any older
2446 .gdb_index sections it finds. This will restore performance, but the
2447 ability to set breakpoints on inlined functions will be lost in symbol
2448 files with older .gdb_index sections.
2450 The .gdb_index section has also been updated to record more information
2451 about each symbol. This speeds up the "info variables", "info functions"
2452 and "info types" commands when used with programs having the .gdb_index
2453 section, as well as speeding up debugging with shared libraries using
2454 the .gdb_index section.
2456 * Ada support for GDB/MI Variable Objects has been added.
2458 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2463 ** New command -info-os is the MI equivalent of "info os".
2465 ** Output logs ("set logging" and related) now include MI output.
2469 ** "set use-deprecated-index-sections on|off"
2470 "show use-deprecated-index-sections on|off"
2471 Controls the use of deprecated .gdb_index sections.
2473 ** "catch load" and "catch unload" can be used to stop when a shared
2474 library is loaded or unloaded, respectively.
2476 ** "enable count" can be used to auto-disable a breakpoint after
2479 ** "info vtbl" can be used to show the virtual method tables for
2480 C++ and Java objects.
2482 ** "explore" and its sub commands "explore value" and "explore type"
2483 can be used to recursively explore values and types of
2484 expressions. These commands are available only if GDB is
2485 configured with '--with-python'.
2487 ** "info auto-load" shows status of all kinds of auto-loaded files,
2488 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2489 sequences of commands files, "info auto-load python-scripts"
2490 shows status of auto-loading Python script files,
2491 "info auto-load local-gdbinit" shows status of loading init file
2492 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2493 status of inferior specific thread debugging shared library loading.
2495 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2496 and "show auto-load-scripts" commands have been deprecated, use their
2497 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2498 and "show auto-load python-scripts" counterparts instead.
2500 ** "dprintf location,format,args..." creates a dynamic printf, which
2501 is basically a breakpoint that does a printf and immediately
2502 resumes your program's execution, so it is like a printf that you
2503 can insert dynamically at runtime instead of at compiletime.
2505 ** "set print symbol"
2507 Controls whether GDB attempts to display the symbol, if any,
2508 corresponding to addresses it prints. This defaults to "on", but
2509 you can set it to "off" to restore GDB's previous behavior.
2511 * Deprecated commands
2513 ** For the Renesas Super-H architecture, the "regs" command has been
2514 deprecated, and "info all-registers" should be used instead.
2518 Renesas RL78 rl78-*-elf
2519 HP OpenVMS ia64 ia64-hp-openvms*
2521 * GDBserver supports evaluation of breakpoint conditions. When
2522 support is advertised by GDBserver, GDB may be told to send the
2523 breakpoint conditions in bytecode form to GDBserver. GDBserver
2524 will only report the breakpoint trigger to GDB when its condition
2529 set mips compression
2530 show mips compression
2531 Select the compressed ISA encoding used in functions that have no symbol
2532 information available. The encoding can be set to either of:
2535 and is updated automatically from ELF file flags if available.
2537 set breakpoint condition-evaluation
2538 show breakpoint condition-evaluation
2539 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2540 GDBserver ("target"). Default option "auto" chooses the most efficient
2542 This option can improve debugger efficiency depending on the speed of the
2546 Disable auto-loading globally.
2549 Show auto-loading setting of all kinds of auto-loaded files.
2551 set auto-load gdb-scripts on|off
2552 show auto-load gdb-scripts
2553 Control auto-loading of GDB canned sequences of commands files.
2555 set auto-load python-scripts on|off
2556 show auto-load python-scripts
2557 Control auto-loading of Python script files.
2559 set auto-load local-gdbinit on|off
2560 show auto-load local-gdbinit
2561 Control loading of init file (.gdbinit) from current directory.
2563 set auto-load libthread-db on|off
2564 show auto-load libthread-db
2565 Control auto-loading of inferior specific thread debugging shared library.
2567 set auto-load scripts-directory <dir1>[:<dir2>...]
2568 show auto-load scripts-directory
2569 Set a list of directories from which to load auto-loaded scripts.
2570 Automatically loaded Python scripts and GDB scripts are located in one
2571 of the directories listed by this option.
2572 The delimiter (':' above) may differ according to the host platform.
2574 set auto-load safe-path <dir1>[:<dir2>...]
2575 show auto-load safe-path
2576 Set a list of directories from which it is safe to auto-load files.
2577 The delimiter (':' above) may differ according to the host platform.
2579 set debug auto-load on|off
2580 show debug auto-load
2581 Control display of debugging info for auto-loading the files above.
2583 set dprintf-style gdb|call|agent
2585 Control the way in which a dynamic printf is performed; "gdb"
2586 requests a GDB printf command, while "call" causes dprintf to call a
2587 function in the inferior. "agent" requests that the target agent
2588 (such as GDBserver) do the printing.
2590 set dprintf-function <expr>
2591 show dprintf-function
2592 set dprintf-channel <expr>
2593 show dprintf-channel
2594 Set the function and optional first argument to the call when using
2595 the "call" style of dynamic printf.
2597 set disconnected-dprintf on|off
2598 show disconnected-dprintf
2599 Control whether agent-style dynamic printfs continue to be in effect
2600 after GDB disconnects.
2602 * New configure options
2604 --with-auto-load-dir
2605 Configure default value for the 'set auto-load scripts-directory'
2606 setting above. It defaults to '$debugdir:$datadir/auto-load',
2607 $debugdir representing global debugging info directories (available
2608 via 'show debug-file-directory') and $datadir representing GDB's data
2609 directory (available via 'show data-directory').
2611 --with-auto-load-safe-path
2612 Configure default value for the 'set auto-load safe-path' setting
2613 above. It defaults to the --with-auto-load-dir setting.
2615 --without-auto-load-safe-path
2616 Set 'set auto-load safe-path' to '/', effectively disabling this
2619 * New remote packets
2621 z0/z1 conditional breakpoints extension
2623 The z0/z1 breakpoint insertion packets have been extended to carry
2624 a list of conditional expressions over to the remote stub depending on the
2625 condition evaluation mode. The use of this extension can be controlled
2626 via the "set remote conditional-breakpoints-packet" command.
2630 Specify the signals which the remote stub may pass to the debugged
2631 program without GDB involvement.
2633 * New command line options
2635 --init-command=FILE, -ix Like --command, -x but execute it
2636 before loading inferior.
2637 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2638 execute it before loading inferior.
2640 *** Changes in GDB 7.4
2642 * GDB now handles ambiguous linespecs more consistently; the existing
2643 FILE:LINE support has been expanded to other types of linespecs. A
2644 breakpoint will now be set on all matching locations in all
2645 inferiors, and locations will be added or removed according to
2648 * GDB now allows you to skip uninteresting functions and files when
2649 stepping with the "skip function" and "skip file" commands.
2651 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2652 and "show remote hardware-watchpoint-length-limit". These allows to
2653 set or show the maximum length limit (in bytes) of a remote
2654 target hardware watchpoint.
2656 This allows e.g. to use "unlimited" hardware watchpoints with the
2657 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2658 watchpoints are slower than real hardware watchpoints but are
2659 significantly faster than gdb software watchpoints.
2663 ** The register_pretty_printer function in module gdb.printing now takes
2664 an optional `replace' argument. If True, the new printer replaces any
2667 ** The "maint set python print-stack on|off" command has been
2668 deprecated and will be deleted in GDB 7.5.
2669 A new command: "set python print-stack none|full|message" has
2670 replaced it. Additionally, the default for "print-stack" is
2671 now "message", which just prints the error message without
2674 ** A prompt substitution hook (prompt_hook) is now available to the
2677 ** A new Python module, gdb.prompt has been added to the GDB Python
2678 modules library. This module provides functionality for
2679 escape sequences in prompts (used by set/show
2680 extended-prompt). These escape sequences are replaced by their
2681 corresponding value.
2683 ** Python commands and convenience-functions located in
2684 'data-directory'/python/gdb/command and
2685 'data-directory'/python/gdb/function are now automatically loaded
2688 ** Blocks now provide four new attributes. global_block and
2689 static_block will return the global and static blocks
2690 respectively. is_static and is_global are boolean attributes
2691 that indicate if the block is one of those two types.
2693 ** Symbols now provide the "type" attribute, the type of the symbol.
2695 ** The "gdb.breakpoint" function has been deprecated in favor of
2698 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2699 of a function. This class is based on the "finish" command
2700 available in the CLI.
2702 ** Type objects for struct and union types now allow access to
2703 the fields using standard Python dictionary (mapping) methods.
2704 For example, "some_type['myfield']" now works, as does
2705 "some_type.items()".
2707 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2710 ** A new function, "deep_items" has been added to the gdb.types
2711 module in the GDB Python modules library. This function returns
2712 an iterator over the fields of a struct or union type. Unlike
2713 the standard Python "iteritems" method, it will recursively traverse
2714 any anonymous fields.
2718 ** "*stopped" events can report several new "reason"s, such as
2721 ** Breakpoint changes are now notified using new async records, like
2722 "=breakpoint-modified".
2724 ** New command -ada-task-info.
2726 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2727 $sdir specifies the default system locations of shared libraries.
2728 $pdir specifies the directory where the libpthread used by the application
2731 GDB no longer looks in $sdir and $pdir after it has searched the directories
2732 mentioned in libthread-db-search-path. If you want to search those
2733 directories, they must be specified in libthread-db-search-path.
2734 The default value of libthread-db-search-path on GNU/Linux and Solaris
2735 systems is now "$sdir:$pdir".
2737 $pdir is not supported by gdbserver, it is currently ignored.
2738 $sdir is supported by gdbserver.
2740 * New configure option --with-iconv-bin.
2741 When using the internationalization support like the one in the GNU C
2742 library, GDB will invoke the "iconv" program to get a list of supported
2743 character sets. If this program lives in a non-standard location, one can
2744 use this option to specify where to find it.
2746 * When natively debugging programs on PowerPC BookE processors running
2747 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2748 watchpoints, which specify a mask in addition to an address to watch.
2749 The mask specifies that some bits of an address (the bits which are
2750 reset in the mask) should be ignored when matching the address accessed
2751 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2752 section in the user manual for more details.
2754 * The new option --once causes GDBserver to stop listening for connections once
2755 the first connection is made. The listening port used by GDBserver will
2756 become available after that.
2758 * New commands "info macros" and "alias" have been added.
2760 * New function parameters suffix @entry specifies value of function parameter
2761 at the time the function got called. Entry values are available only since
2767 "!" is now an alias of the "shell" command.
2768 Note that no space is needed between "!" and SHELL COMMAND.
2772 watch EXPRESSION mask MASK_VALUE
2773 The watch command now supports the mask argument which allows creation
2774 of masked watchpoints, if the current architecture supports this feature.
2776 info auto-load-scripts [REGEXP]
2777 This command was formerly named "maintenance print section-scripts".
2778 It is now generally useful and is no longer a maintenance-only command.
2780 info macro [-all] [--] MACRO
2781 The info macro command has new options `-all' and `--'. The first for
2782 printing all definitions of a macro. The second for explicitly specifying
2783 the end of arguments and the beginning of the macro name in case the macro
2784 name starts with a hyphen.
2786 collect[/s] EXPRESSIONS
2787 The tracepoint collect command now takes an optional modifier "/s"
2788 that directs it to dereference pointer-to-character types and
2789 collect the bytes of memory up to a zero byte. The behavior is
2790 similar to what you see when you use the regular print command on a
2791 string. An optional integer following the "/s" sets a bound on the
2792 number of bytes that will be collected.
2795 The trace start command now interprets any supplied arguments as a
2796 note to be recorded with the trace run, with an effect similar to
2797 setting the variable trace-notes.
2800 The trace stop command now interprets any arguments as a note to be
2801 mentioned along with the tstatus report that the trace was stopped
2802 with a command. The effect is similar to setting the variable
2805 * Tracepoints can now be enabled and disabled at any time after a trace
2806 experiment has been started using the standard "enable" and "disable"
2807 commands. It is now possible to start a trace experiment with no enabled
2808 tracepoints; GDB will display a warning, but will allow the experiment to
2809 begin, assuming that tracepoints will be enabled as needed while the trace
2812 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2813 locations with 4-byte instructions, when they were previously
2814 limited to locations with instructions of 5 bytes or longer.
2818 set debug dwarf2-read
2819 show debug dwarf2-read
2820 Turns on or off display of debugging messages related to reading
2821 DWARF debug info. The default is off.
2823 set debug symtab-create
2824 show debug symtab-create
2825 Turns on or off display of debugging messages related to symbol table
2826 creation. The default is off.
2829 show extended-prompt
2830 Set the GDB prompt, and allow escape sequences to be inserted to
2831 display miscellaneous information (see 'help set extended-prompt'
2832 for the list of sequences). This prompt (and any information
2833 accessed through the escape sequences) is updated every time the
2834 prompt is displayed.
2836 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2837 show print entry-values
2838 Set printing of frame argument values at function entry. In some cases
2839 GDB can determine the value of function argument which was passed by the
2840 function caller, even if the value was modified inside the called function.
2842 set debug entry-values
2843 show debug entry-values
2844 Control display of debugging info for determining frame argument values at
2845 function entry and virtual tail call frames.
2847 set basenames-may-differ
2848 show basenames-may-differ
2849 Set whether a source file may have multiple base names.
2850 (A "base name" is the name of a file with the directory part removed.
2851 Example: The base name of "/home/user/hello.c" is "hello.c".)
2852 If set, GDB will canonicalize file names (e.g., expand symlinks)
2853 before comparing them. Canonicalization is an expensive operation,
2854 but it allows the same file be known by more than one base name.
2855 If not set (the default), all source files are assumed to have just
2856 one base name, and gdb will do file name comparisons more efficiently.
2862 Set a user name and notes for the current and any future trace runs.
2863 This is useful for long-running and/or disconnected traces, to
2864 inform others (or yourself) as to who is running the trace, supply
2865 contact information, or otherwise explain what is going on.
2867 set trace-stop-notes
2868 show trace-stop-notes
2869 Set a note attached to the trace run, that is displayed when the
2870 trace has been stopped by a tstop command. This is useful for
2871 instance as an explanation, if you are stopping a trace run that was
2872 started by someone else.
2874 * New remote packets
2878 Dynamically enable a tracepoint in a started trace experiment.
2882 Dynamically disable a tracepoint in a started trace experiment.
2886 Set the user and notes of the trace run.
2890 Query the current status of a tracepoint.
2894 Query the minimum length of instruction at which a fast tracepoint may
2897 * Dcache size (number of lines) and line-size are now runtime-configurable
2898 via "set dcache line" and "set dcache line-size" commands.
2902 Texas Instruments TMS320C6x tic6x-*-*
2906 Renesas RL78 rl78-*-elf
2908 *** Changes in GDB 7.3.1
2910 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2912 *** Changes in GDB 7.3
2914 * GDB has a new command: "thread find [REGEXP]".
2915 It finds the thread id whose name, target id, or thread extra info
2916 matches the given regular expression.
2918 * The "catch syscall" command now works on mips*-linux* targets.
2920 * The -data-disassemble MI command now supports modes 2 and 3 for
2921 dumping the instruction opcodes.
2923 * New command line options
2925 -data-directory DIR Specify DIR as the "data-directory".
2926 This is mostly for testing purposes.
2928 * The "maint set python auto-load on|off" command has been renamed to
2929 "set auto-load-scripts on|off".
2931 * GDB has a new command: "set directories".
2932 It is like the "dir" command except that it replaces the
2933 source path list instead of augmenting it.
2935 * GDB now understands thread names.
2937 On GNU/Linux, "info threads" will display the thread name as set by
2938 prctl or pthread_setname_np.
2940 There is also a new command, "thread name", which can be used to
2941 assign a name internally for GDB to display.
2944 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2945 has been integrated into GDB.
2949 ** The function gdb.Write now accepts an optional keyword 'stream'.
2950 This keyword, when provided, will direct the output to either
2951 stdout, stderr, or GDB's logging output.
2953 ** Parameters can now be be sub-classed in Python, and in particular
2954 you may implement the get_set_doc and get_show_doc functions.
2955 This improves how Parameter set/show documentation is processed
2956 and allows for more dynamic content.
2958 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2959 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2960 have an is_valid method.
2962 ** Breakpoints can now be sub-classed in Python, and in particular
2963 you may implement a 'stop' function that is executed each time
2964 the inferior reaches that breakpoint.
2966 ** New function gdb.lookup_global_symbol looks up a global symbol.
2968 ** GDB values in Python are now callable if the value represents a
2969 function. For example, if 'some_value' represents a function that
2970 takes two integer parameters and returns a value, you can call
2971 that function like so:
2973 result = some_value (10,20)
2975 ** Module gdb.types has been added.
2976 It contains a collection of utilities for working with gdb.Types objects:
2977 get_basic_type, has_field, make_enum_dict.
2979 ** Module gdb.printing has been added.
2980 It contains utilities for writing and registering pretty-printers.
2981 New classes: PrettyPrinter, SubPrettyPrinter,
2982 RegexpCollectionPrettyPrinter.
2983 New function: register_pretty_printer.
2985 ** New commands "info pretty-printers", "enable pretty-printer" and
2986 "disable pretty-printer" have been added.
2988 ** gdb.parameter("directories") is now available.
2990 ** New function gdb.newest_frame returns the newest frame in the
2993 ** The gdb.InferiorThread class has a new "name" attribute. This
2994 holds the thread's name.
2996 ** Python Support for Inferior events.
2997 Python scripts can add observers to be notified of events
2998 occurring in the process being debugged.
2999 The following events are currently supported:
3000 - gdb.events.cont Continue event.
3001 - gdb.events.exited Inferior exited event.
3002 - gdb.events.stop Signal received, and Breakpoint hit events.
3006 ** GDB now puts template parameters in scope when debugging in an
3007 instantiation. For example, if you have:
3009 template<int X> int func (void) { return X; }
3011 then if you step into func<5>, "print X" will show "5". This
3012 feature requires proper debuginfo support from the compiler; it
3013 was added to GCC 4.5.
3015 ** The motion commands "next", "finish", "until", and "advance" now
3016 work better when exceptions are thrown. In particular, GDB will
3017 no longer lose control of the inferior; instead, the GDB will
3018 stop the inferior at the point at which the exception is caught.
3019 This functionality requires a change in the exception handling
3020 code that was introduced in GCC 4.5.
3022 * GDB now follows GCC's rules on accessing volatile objects when
3023 reading or writing target state during expression evaluation.
3024 One notable difference to prior behavior is that "print x = 0"
3025 no longer generates a read of x; the value of the assignment is
3026 now always taken directly from the value being assigned.
3028 * GDB now has some support for using labels in the program's source in
3029 linespecs. For instance, you can use "advance label" to continue
3030 execution to a label.
3032 * GDB now has support for reading and writing a new .gdb_index
3033 section. This section holds a fast index of DWARF debugging
3034 information and can be used to greatly speed up GDB startup and
3035 operation. See the documentation for `save gdb-index' for details.
3037 * The "watch" command now accepts an optional "-location" argument.
3038 When used, this causes GDB to watch the memory referred to by the
3039 expression. Such a watchpoint is never deleted due to it going out
3042 * GDB now supports thread debugging of core dumps on GNU/Linux.
3044 GDB now activates thread debugging using the libthread_db library
3045 when debugging GNU/Linux core dumps, similarly to when debugging
3046 live processes. As a result, when debugging a core dump file, GDB
3047 is now able to display pthread_t ids of threads. For example, "info
3048 threads" shows the same output as when debugging the process when it
3049 was live. In earlier releases, you'd see something like this:
3052 * 1 LWP 6780 main () at main.c:10
3054 While now you see this:
3057 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
3059 It is also now possible to inspect TLS variables when debugging core
3062 When debugging a core dump generated on a machine other than the one
3063 used to run GDB, you may need to point GDB at the correct
3064 libthread_db library with the "set libthread-db-search-path"
3065 command. See the user manual for more details on this command.
3067 * When natively debugging programs on PowerPC BookE processors running
3068 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
3069 which stop execution of the inferior whenever it executes an instruction
3070 at any address within the specified range. See the "PowerPC Embedded"
3071 section in the user manual for more details.
3073 * New features in the GDB remote stub, GDBserver
3075 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
3076 and i686 LynxOS (version 5.x).
3078 ** GDBserver is now supported on Blackfin Linux.
3080 * New native configurations
3082 ia64 HP-UX ia64-*-hpux*
3086 Analog Devices, Inc. Blackfin Processor bfin-*
3088 * Ada task switching is now supported on sparc-elf targets when
3089 debugging a program using the Ravenscar Profile. For more information,
3090 see the "Tasking Support when using the Ravenscar Profile" section
3091 in the GDB user manual.
3093 * Guile support was removed.
3095 * New features in the GNU simulator
3097 ** The --map-info flag lists all known core mappings.
3099 ** CFI flashes may be simulated via the "cfi" device.
3101 *** Changes in GDB 7.2
3103 * Shared library support for remote targets by default
3105 When GDB is configured for a generic, non-OS specific target, like
3106 for example, --target=arm-eabi or one of the many *-*-elf targets,
3107 GDB now queries remote stubs for loaded shared libraries using the
3108 `qXfer:libraries:read' packet. Previously, shared library support
3109 was always disabled for such configurations.
3113 ** Argument Dependent Lookup (ADL)
3115 In C++ ADL lookup directs function search to the namespaces of its
3116 arguments even if the namespace has not been imported.
3126 Here the compiler will search for `foo' in the namespace of 'b'
3127 and find A::foo. GDB now supports this. This construct is commonly
3128 used in the Standard Template Library for operators.
3130 ** Improved User Defined Operator Support
3132 In addition to member operators, GDB now supports lookup of operators
3133 defined in a namespace and imported with a `using' directive, operators
3134 defined in the global scope, operators imported implicitly from an
3135 anonymous namespace, and the ADL operators mentioned in the previous
3137 GDB now also supports proper overload resolution for all the previously
3138 mentioned flavors of operators.
3140 ** static const class members
3142 Printing of static const class members that are initialized in the
3143 class definition has been fixed.
3145 * Windows Thread Information Block access.
3147 On Windows targets, GDB now supports displaying the Windows Thread
3148 Information Block (TIB) structure. This structure is visible either
3149 by using the new command `info w32 thread-information-block' or, by
3150 dereferencing the new convenience variable named `$_tlb', a
3151 thread-specific pointer to the TIB. This feature is also supported
3152 when remote debugging using GDBserver.
3154 * Static tracepoints
3156 Static tracepoints are calls in the user program into a tracing
3157 library. One such library is a port of the LTTng kernel tracer to
3158 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3159 When debugging with GDBserver, GDB now supports combining the GDB
3160 tracepoint machinery with such libraries. For example: the user can
3161 use GDB to probe a static tracepoint marker (a call from the user
3162 program into the tracing library) with the new "strace" command (see
3163 "New commands" below). This creates a "static tracepoint" in the
3164 breakpoint list, that can be manipulated with the same feature set
3165 as fast and regular tracepoints. E.g., collect registers, local and
3166 global variables, collect trace state variables, and define
3167 tracepoint conditions. In addition, the user can collect extra
3168 static tracepoint marker specific data, by collecting the new
3169 $_sdata internal variable. When analyzing the trace buffer, you can
3170 inspect $_sdata like any other variable available to GDB. For more
3171 information, see the "Tracepoints" chapter in GDB user manual. New
3172 remote packets have been defined to support static tracepoints, see
3173 the "New remote packets" section below.
3175 * Better reconstruction of tracepoints after disconnected tracing
3177 GDB will attempt to download the original source form of tracepoint
3178 definitions when starting a trace run, and then will upload these
3179 upon reconnection to the target, resulting in a more accurate
3180 reconstruction of the tracepoints that are in use on the target.
3184 You can now exercise direct control over the ways that GDB can
3185 affect your program. For instance, you can disallow the setting of
3186 breakpoints, so that the program can run continuously (assuming
3187 non-stop mode). In addition, the "observer" variable is available
3188 to switch all of the different controls; in observer mode, GDB
3189 cannot affect the target's behavior at all, which is useful for
3190 tasks like diagnosing live systems in the field.
3192 * The new convenience variable $_thread holds the number of the
3195 * New remote packets
3199 Return the address of the Windows Thread Information Block of a given thread.
3203 In response to several of the tracepoint packets, the target may now
3204 also respond with a number of intermediate `qRelocInsn' request
3205 packets before the final result packet, to have GDB handle
3206 relocating an instruction to execute at a different address. This
3207 is particularly useful for stubs that support fast tracepoints. GDB
3208 reports support for this feature in the qSupported packet.
3212 List static tracepoint markers in the target program.
3216 List static tracepoint markers at a given address in the target
3219 qXfer:statictrace:read
3221 Read the static trace data collected (by a `collect $_sdata'
3222 tracepoint action). The remote stub reports support for this packet
3223 to gdb's qSupported query.
3227 Send the current settings of GDB's permission flags.
3231 Send part of the source (textual) form of a tracepoint definition,
3232 which includes location, conditional, and action list.
3234 * The source command now accepts a -s option to force searching for the
3235 script in the source search path even if the script name specifies
3238 * New features in the GDB remote stub, GDBserver
3240 - GDBserver now support tracepoints (including fast tracepoints, and
3241 static tracepoints). The feature is currently supported by the
3242 i386-linux and amd64-linux builds. See the "Tracepoints support
3243 in gdbserver" section in the manual for more information.
3245 GDBserver JIT compiles the tracepoint's conditional agent
3246 expression bytecode into native code whenever possible for low
3247 overhead dynamic tracepoints conditionals. For such tracepoints,
3248 an expression that examines program state is evaluated when the
3249 tracepoint is reached, in order to determine whether to capture
3250 trace data. If the condition is simple and false, processing the
3251 tracepoint finishes very quickly and no data is gathered.
3253 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3254 for static tracepoints support.
3256 - GDBserver now supports x86_64 Windows 64-bit debugging.
3258 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3259 it understands register description.
3261 * The --batch flag now disables pagination and queries.
3263 * X86 general purpose registers
3265 GDB now supports reading/writing byte, word and double-word x86
3266 general purpose registers directly. This means you can use, say,
3267 $ah or $ax to refer, respectively, to the byte register AH and
3268 16-bit word register AX that are actually portions of the 32-bit
3269 register EAX or 64-bit register RAX.
3271 * The `commands' command now accepts a range of breakpoints to modify.
3272 A plain `commands' following a command that creates multiple
3273 breakpoints affects all the breakpoints set by that command. This
3274 applies to breakpoints set by `rbreak', and also applies when a
3275 single `break' command creates multiple breakpoints (e.g.,
3276 breakpoints on overloaded c++ functions).
3278 * The `rbreak' command now accepts a filename specification as part of
3279 its argument, limiting the functions selected by the regex to those
3280 in the specified file.
3282 * Support for remote debugging Windows and SymbianOS shared libraries
3283 from Unix hosts has been improved. Non Windows GDB builds now can
3284 understand target reported file names that follow MS-DOS based file
3285 system semantics, such as file names that include drive letters and
3286 use the backslash character as directory separator. This makes it
3287 possible to transparently use the "set sysroot" and "set
3288 solib-search-path" on Unix hosts to point as host copies of the
3289 target's shared libraries. See the new command "set
3290 target-file-system-kind" described below, and the "Commands to
3291 specify files" section in the user manual for more information.
3295 eval template, expressions...
3296 Convert the values of one or more expressions under the control
3297 of the string template to a command line, and call it.
3299 set target-file-system-kind unix|dos-based|auto
3300 show target-file-system-kind
3301 Set or show the assumed file system kind for target reported file
3304 save breakpoints <filename>
3305 Save all current breakpoint definitions to a file suitable for use
3306 in a later debugging session. To read the saved breakpoint
3307 definitions, use the `source' command.
3309 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3312 info static-tracepoint-markers
3313 Display information about static tracepoint markers in the target.
3315 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3316 Define a static tracepoint by probing a marker at the given
3317 function, line, address, or marker ID.
3321 Enable and disable observer mode.
3323 set may-write-registers on|off
3324 set may-write-memory on|off
3325 set may-insert-breakpoints on|off
3326 set may-insert-tracepoints on|off
3327 set may-insert-fast-tracepoints on|off
3328 set may-interrupt on|off
3329 Set individual permissions for GDB effects on the target. Note that
3330 some of these settings can have undesirable or surprising
3331 consequences, particularly when changed in the middle of a session.
3332 For instance, disabling the writing of memory can prevent
3333 breakpoints from being inserted, cause single-stepping to fail, or
3334 even crash your program, if you disable after breakpoints have been
3335 inserted. However, GDB should not crash.
3337 set record memory-query on|off
3338 show record memory-query
3339 Control whether to stop the inferior if memory changes caused
3340 by an instruction cannot be recorded.
3345 The disassemble command now supports "start,+length" form of two arguments.
3349 ** GDB now provides a new directory location, called the python directory,
3350 where Python scripts written for GDB can be installed. The location
3351 of that directory is <data-directory>/python, where <data-directory>
3352 is the GDB data directory. For more details, see section `Scripting
3353 GDB using Python' in the manual.
3355 ** The GDB Python API now has access to breakpoints, symbols, symbol
3356 tables, program spaces, inferiors, threads and frame's code blocks.
3357 Additionally, GDB Parameters can now be created from the API, and
3358 manipulated via set/show in the CLI.
3360 ** New functions gdb.target_charset, gdb.target_wide_charset,
3361 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3363 ** New exception gdb.GdbError.
3365 ** Pretty-printers are now also looked up in the current program space.
3367 ** Pretty-printers can now be individually enabled and disabled.
3369 ** GDB now looks for names of Python scripts to auto-load in a
3370 special section named `.debug_gdb_scripts', in addition to looking
3371 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3373 * Tracepoint actions were unified with breakpoint commands. In particular,
3374 there are no longer differences in "info break" output for breakpoints and
3375 tracepoints and the "commands" command can be used for both tracepoints and
3376 regular breakpoints.
3380 ARM Symbian arm*-*-symbianelf*
3382 * D language support.
3383 GDB now supports debugging programs written in the D programming
3386 * GDB now supports the extended ptrace interface for PowerPC which is
3387 available since Linux kernel version 2.6.34. This automatically enables
3388 any hardware breakpoints and additional hardware watchpoints available in
3389 the processor. The old ptrace interface exposes just one hardware
3390 watchpoint and no hardware breakpoints.
3392 * GDB is now able to use the Data Value Compare (DVC) register available on
3393 embedded PowerPC processors to implement in hardware simple watchpoint
3394 conditions of the form:
3396 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3398 This works in native GDB running on Linux kernels with the extended ptrace
3399 interface mentioned above.
3401 *** Changes in GDB 7.1
3405 ** Namespace Support
3407 GDB now supports importing of namespaces in C++. This enables the
3408 user to inspect variables from imported namespaces. Support for
3409 namepace aliasing has also been added. So, if a namespace is
3410 aliased in the current scope (e.g. namepace C=A; ) the user can
3411 print variables using the alias (e.g. (gdb) print C::x).
3415 All known bugs relating to the printing of virtual base class were
3416 fixed. It is now possible to call overloaded static methods using a
3421 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3422 and reinterpret_cast<> are now handled by the C++ expression parser.
3426 Xilinx MicroBlaze microblaze-*-*
3431 Xilinx MicroBlaze microblaze
3434 * Multi-program debugging.
3436 GDB now has support for multi-program (a.k.a. multi-executable or
3437 multi-exec) debugging. This allows for debugging multiple inferiors
3438 simultaneously each running a different program under the same GDB
3439 session. See "Debugging Multiple Inferiors and Programs" in the
3440 manual for more information. This implied some user visible changes
3441 in the multi-inferior support. For example, "info inferiors" now
3442 lists inferiors that are not running yet or that have exited
3443 already. See also "New commands" and "New options" below.
3445 * New tracing features
3447 GDB's tracepoint facility now includes several new features:
3449 ** Trace state variables
3451 GDB tracepoints now include support for trace state variables, which
3452 are variables managed by the target agent during a tracing
3453 experiment. They are useful for tracepoints that trigger each
3454 other, so for instance one tracepoint can count hits in a variable,
3455 and then a second tracepoint has a condition that is true when the
3456 count reaches a particular value. Trace state variables share the
3457 $-syntax of GDB convenience variables, and can appear in both
3458 tracepoint actions and condition expressions. Use the "tvariable"
3459 command to create, and "info tvariables" to view; see "Trace State
3460 Variables" in the manual for more detail.
3464 GDB now includes an option for defining fast tracepoints, which
3465 targets may implement more efficiently, such as by installing a jump
3466 into the target agent rather than a trap instruction. The resulting
3467 speedup can be by two orders of magnitude or more, although the
3468 tradeoff is that some program locations on some target architectures
3469 might not allow fast tracepoint installation, for instance if the
3470 instruction to be replaced is shorter than the jump. To request a
3471 fast tracepoint, use the "ftrace" command, with syntax identical to
3472 the regular trace command.
3474 ** Disconnected tracing
3476 It is now possible to detach GDB from the target while it is running
3477 a trace experiment, then reconnect later to see how the experiment
3478 is going. In addition, a new variable disconnected-tracing lets you
3479 tell the target agent whether to continue running a trace if the
3480 connection is lost unexpectedly.
3484 GDB now has the ability to save the trace buffer into a file, and
3485 then use that file as a target, similarly to you can do with
3486 corefiles. You can select trace frames, print data that was
3487 collected in them, and use tstatus to display the state of the
3488 tracing run at the moment that it was saved. To create a trace
3489 file, use "tsave <filename>", and to use it, do "target tfile
3492 ** Circular trace buffer
3494 You can ask the target agent to handle the trace buffer as a
3495 circular buffer, discarding the oldest trace frames to make room for
3496 newer ones, by setting circular-trace-buffer to on. This feature may
3497 not be available for all target agents.
3502 The disassemble command, when invoked with two arguments, now requires
3503 the arguments to be comma-separated.
3506 The info variables command now displays variable definitions. Files
3507 which only declare a variable are not shown.
3510 The source command is now capable of sourcing Python scripts.
3511 This feature is dependent on the debugger being build with Python
3514 Related to this enhancement is also the introduction of a new command
3515 "set script-extension" (see below).
3517 * New commands (for set/show, see "New options" below)
3519 record save [<FILENAME>]
3520 Save a file (in core file format) containing the process record
3521 execution log for replay debugging at a later time.
3523 record restore <FILENAME>
3524 Restore the process record execution log that was saved at an
3525 earlier time, for replay debugging.
3527 add-inferior [-copies <N>] [-exec <FILENAME>]
3530 clone-inferior [-copies <N>] [ID]
3531 Make a new inferior ready to execute the same program another
3532 inferior has loaded.
3537 maint info program-spaces
3538 List the program spaces loaded into GDB.
3540 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3541 show remote interrupt-sequence
3542 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3543 as the sequence to the remote target in order to interrupt the execution.
3544 Ctrl-C is a default. Some system prefers BREAK which is high level of
3545 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3546 Magic SysRq g. It is BREAK signal and character 'g'.
3548 set remote interrupt-on-connect [on | off]
3549 show remote interrupt-on-connect
3550 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3551 remote target when gdb connects to it. This is needed when you debug
3554 set remotebreak [on | off]
3556 Deprecated. Use "set/show remote interrupt-sequence" instead.
3558 tvariable $NAME [ = EXP ]
3559 Create or modify a trace state variable.
3562 List trace state variables and their values.
3564 delete tvariable $NAME ...
3565 Delete one or more trace state variables.
3568 Evaluate the given expressions without collecting anything into the
3569 trace buffer. (Valid in tracepoint actions only.)
3571 ftrace FN / FILE:LINE / *ADDR
3572 Define a fast tracepoint at the given function, line, or address.
3574 * New expression syntax
3576 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3577 GDB now parses 0b101010 identically with 42.
3581 set follow-exec-mode new|same
3582 show follow-exec-mode
3583 Control whether GDB reuses the same inferior across an exec call or
3584 creates a new one. This is useful to be able to restart the old
3585 executable after the inferior having done an exec call.
3587 set default-collect EXPR, ...
3588 show default-collect
3589 Define a list of expressions to be collected at each tracepoint.
3590 This is a useful way to ensure essential items are not overlooked,
3591 such as registers or a critical global variable.
3593 set disconnected-tracing
3594 show disconnected-tracing
3595 If set to 1, the target is instructed to continue tracing if it
3596 loses its connection to GDB. If 0, the target is to stop tracing
3599 set circular-trace-buffer
3600 show circular-trace-buffer
3601 If set to on, the target is instructed to use a circular trace buffer
3602 and discard the oldest trace frames instead of stopping the trace due
3603 to a full trace buffer. If set to off, the trace stops when the buffer
3604 fills up. Some targets may not support this.
3606 set script-extension off|soft|strict
3607 show script-extension
3608 If set to "off", the debugger does not perform any script language
3609 recognition, and all sourced files are assumed to be GDB scripts.
3610 If set to "soft" (the default), files are sourced according to
3611 filename extension, falling back to GDB scripts if the first
3613 If set to "strict", files are sourced according to filename extension.
3615 set ada trust-PAD-over-XVS on|off
3616 show ada trust-PAD-over-XVS
3617 If off, activate a workaround against a bug in the debugging information
3618 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3619 the GCC sources for more information about the GNAT encoding and
3620 PAD types in particular). It is always safe to set this option to
3621 off, but this introduces a slight performance penalty. The default
3624 * Python API Improvements
3626 ** GDB provides the new class gdb.LazyString. This is useful in
3627 some pretty-printing cases. The new method gdb.Value.lazy_string
3628 provides a simple way to create objects of this type.
3630 ** The fields returned by gdb.Type.fields now have an
3631 `is_base_class' attribute.
3633 ** The new method gdb.Type.range returns the range of an array type.
3635 ** The new method gdb.parse_and_eval can be used to parse and
3636 evaluate an expression.
3638 * New remote packets
3641 Define a trace state variable.
3644 Get the current value of a trace state variable.
3647 Set desired tracing behavior upon disconnection.
3650 Set the trace buffer to be linear or circular.
3653 Get data about the tracepoints currently in use.
3657 Process record now works correctly with hardware watchpoints.
3659 Multiple bug fixes have been made to the mips-irix port, making it
3660 much more reliable. In particular:
3661 - Debugging threaded applications is now possible again. Previously,
3662 GDB would hang while starting the program, or while waiting for
3663 the program to stop at a breakpoint.
3664 - Attaching to a running process no longer hangs.
3665 - An error occurring while loading a core file has been fixed.
3666 - Changing the value of the PC register now works again. This fixes
3667 problems observed when using the "jump" command, or when calling
3668 a function from GDB, or even when assigning a new value to $pc.
3669 - With the "finish" and "return" commands, the return value for functions
3670 returning a small array is now correctly printed.
3671 - It is now possible to break on shared library code which gets executed
3672 during a shared library init phase (code executed while executing
3673 their .init section). Previously, the breakpoint would have no effect.
3674 - GDB is now able to backtrace through the signal handler for
3675 non-threaded programs.
3677 PIE (Position Independent Executable) programs debugging is now supported.
3678 This includes debugging execution of PIC (Position Independent Code) shared
3679 libraries although for that, it should be possible to run such libraries as an
3682 *** Changes in GDB 7.0
3684 * GDB now has an interface for JIT compilation. Applications that
3685 dynamically generate code can create symbol files in memory and register
3686 them with GDB. For users, the feature should work transparently, and
3687 for JIT developers, the interface is documented in the GDB manual in the
3688 "JIT Compilation Interface" chapter.
3690 * Tracepoints may now be conditional. The syntax is as for
3691 breakpoints; either an "if" clause appended to the "trace" command,
3692 or the "condition" command is available. GDB sends the condition to
3693 the target for evaluation using the same bytecode format as is used
3694 for tracepoint actions.
3696 * The disassemble command now supports: an optional /r modifier, print the
3697 raw instructions in hex as well as in symbolic form, and an optional /m
3698 modifier to print mixed source+assembly.
3700 * Process record and replay
3702 In a architecture environment that supports ``process record and
3703 replay'', ``process record and replay'' target can record a log of
3704 the process execution, and replay it with both forward and reverse
3707 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3708 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3709 set execution-direction {forward|reverse}, for targets that support
3712 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3713 feature is available with a native GDB running on kernel version
3716 * GDB now has support for multi-byte and wide character sets on the
3717 target. Strings whose character type is wchar_t, char16_t, or
3718 char32_t are now correctly printed. GDB supports wide- and unicode-
3719 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3720 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3721 `printf'. This feature requires iconv to work properly; if your
3722 system does not have a working iconv, GDB can use GNU libiconv. See
3723 the installation instructions for more information.
3725 * GDB now supports automatic retrieval of shared library files from
3726 remote targets. To use this feature, specify a system root that begins
3727 with the `remote:' prefix, either via the `set sysroot' command or via
3728 the `--with-sysroot' configure-time option.
3730 * "info sharedlibrary" now takes an optional regex of libraries to show,
3731 and it now reports if a shared library has no debugging information.
3733 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3734 now complete on file names.
3736 * When completing in expressions, gdb will attempt to limit
3737 completions to allowable structure or union fields, where appropriate.
3738 For instance, consider:
3740 # struct example { int f1; double f2; };
3741 # struct example variable;
3744 If the user types TAB at the end of this command line, the available
3745 completions will be "f1" and "f2".
3747 * Inlined functions are now supported. They show up in backtraces, and
3748 the "step", "next", and "finish" commands handle them automatically.
3750 * GDB now supports the token-splicing (##) and stringification (#)
3751 operators when expanding macros. It also supports variable-arity
3754 * GDB now supports inspecting extra signal information, exported by
3755 the new $_siginfo convenience variable. The feature is currently
3756 implemented on linux ARM, i386 and amd64.
3758 * GDB can now display the VFP floating point registers and NEON vector
3759 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3760 can provide these registers (requires Linux 2.6.30 or later). Remote
3761 and simulator targets may also provide them.
3763 * New remote packets
3766 Search memory for a sequence of bytes.
3769 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3770 operation over reliable transport links. Use of this packet is
3771 controlled by the `set remote noack-packet' command.
3774 Kill the process with the specified process ID. Use this in preference
3775 to `k' when multiprocess protocol extensions are supported.
3778 Obtains additional operating system information
3782 Read or write additional signal information.
3784 * Removed remote protocol undocumented extension
3786 An undocumented extension to the remote protocol's `S' stop reply
3787 packet that permited the stub to pass a process id was removed.
3788 Remote servers should use the `T' stop reply packet instead.
3790 * GDB now supports multiple function calling conventions according to the
3791 DWARF-2 DW_AT_calling_convention function attribute.
3793 * The SH target utilizes the aforementioned change to distinguish between gcc
3794 and Renesas calling convention. It also adds the new CLI commands
3795 `set/show sh calling-convention'.
3797 * GDB can now read compressed debug sections, as produced by GNU gold
3798 with the --compress-debug-sections=zlib flag.
3800 * 64-bit core files are now supported on AIX.
3802 * Thread switching is now supported on Tru64.
3804 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3805 which will be allocated using malloc later in program execution.
3807 * The qXfer:libraries:read remote procotol packet now allows passing a
3808 list of section offsets.
3810 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3811 conditions handling signals delivered during attach or thread creation
3812 have also been fixed.
3814 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3815 From the user's standpoint, all unqualified instances of True and False
3816 are treated as the standard definitions, regardless of context.
3818 * GDB now parses C++ symbol and type names more flexibly. For
3821 template<typename T> class C { };
3824 GDB will now correctly handle all of:
3826 ptype C<char const *>
3827 ptype C<char const*>
3828 ptype C<const char *>
3829 ptype C<const char*>
3831 * New features in the GDB remote stub, gdbserver
3833 - The "--wrapper" command-line argument tells gdbserver to use a
3834 wrapper program to launch programs for debugging.
3836 - On PowerPC and S/390 targets, it is now possible to use a single
3837 gdbserver executable to debug both 32-bit and 64-bit programs.
3838 (This requires gdbserver itself to be built as a 64-bit executable.)
3840 - gdbserver uses the new noack protocol mode for TCP connections to
3841 reduce communications latency, if also supported and enabled in GDB.
3843 - Support for the sparc64-linux-gnu target is now included in
3846 - The amd64-linux build of gdbserver now supports debugging both
3847 32-bit and 64-bit programs.
3849 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3850 now support hardware watchpoints, and will use them automatically
3855 GDB now has support for scripting using Python. Whether this is
3856 available is determined at configure time.
3858 New GDB commands can now be written in Python.
3860 * Ada tasking support
3862 Ada tasks can now be inspected in GDB. The following commands have
3866 Print the list of Ada tasks.
3868 Print detailed information about task number N.
3870 Print the task number of the current task.
3872 Switch the context of debugging to task number N.
3874 * Support for user-defined prefixed commands. The "define" command can
3875 add new commands to existing prefixes, e.g. "target".
3877 * Multi-inferior, multi-process debugging.
3879 GDB now has generalized support for multi-inferior debugging. See
3880 "Debugging Multiple Inferiors" in the manual for more information.
3881 Although availability still depends on target support, the command
3882 set is more uniform now. The GNU/Linux specific multi-forks support
3883 has been migrated to this new framework. This implied some user
3884 visible changes; see "New commands" and also "Removed commands"
3887 * Target descriptions can now describe the target OS ABI. See the
3888 "Target Description Format" section in the user manual for more
3891 * Target descriptions can now describe "compatible" architectures
3892 to indicate that the target can execute applications for a different
3893 architecture in addition to those for the main target architecture.
3894 See the "Target Description Format" section in the user manual for
3897 * Multi-architecture debugging.
3899 GDB now includes general supports for debugging applications on
3900 hybrid systems that use more than one single processor architecture
3901 at the same time. Each such hybrid architecture still requires
3902 specific support to be added. The only hybrid architecture supported
3903 in this version of GDB is the Cell Broadband Engine.
3905 * GDB now supports integrated debugging of Cell/B.E. applications that
3906 use both the PPU and SPU architectures. To enable support for hybrid
3907 Cell/B.E. debugging, you need to configure GDB to support both the
3908 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3909 --enable-targets configure option.
3911 * Non-stop mode debugging.
3913 For some targets, GDB now supports an optional mode of operation in
3914 which you can examine stopped threads while other threads continue
3915 to execute freely. This is referred to as non-stop mode, with the
3916 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3917 section in the user manual for more information.
3919 To be able to support remote non-stop debugging, a remote stub needs
3920 to implement the non-stop mode remote protocol extensions, as
3921 described in the "Remote Non-Stop" section of the user manual. The
3922 GDB remote stub, gdbserver, has been adjusted to support these
3923 extensions on linux targets.
3925 * New commands (for set/show, see "New options" below)
3927 catch syscall [NAME(S) | NUMBER(S)]
3928 Catch system calls. Arguments, which should be names of system
3929 calls or their numbers, mean catch only those syscalls. Without
3930 arguments, every syscall will be caught. When the inferior issues
3931 any of the specified syscalls, GDB will stop and announce the system
3932 call, both when it is called and when its call returns. This
3933 feature is currently available with a native GDB running on the
3934 Linux Kernel, under the following architectures: x86, x86_64,
3935 PowerPC and PowerPC64.
3937 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3939 Search memory for a sequence of bytes.
3941 maint set python print-stack
3942 maint show python print-stack
3943 Show a stack trace when an error is encountered in a Python script.
3946 Invoke CODE by passing it to the Python interpreter.
3951 These allow macros to be defined, undefined, and listed
3955 Show operating system information about processes.
3958 List the inferiors currently under GDB's control.
3961 Switch focus to inferior number NUM.
3964 Detach from inferior number NUM.
3967 Kill inferior number NUM.
3971 set spu stop-on-load
3972 show spu stop-on-load
3973 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3975 set spu auto-flush-cache
3976 show spu auto-flush-cache
3977 Control whether to automatically flush the software-managed cache
3978 during Cell/B.E. debugging.
3980 set sh calling-convention
3981 show sh calling-convention
3982 Control the calling convention used when calling SH target functions.
3985 show debug timestamp
3986 Control display of timestamps with GDB debugging output.
3988 set disassemble-next-line
3989 show disassemble-next-line
3990 Control display of disassembled source lines or instructions when
3993 set remote noack-packet
3994 show remote noack-packet
3995 Set/show the use of remote protocol QStartNoAckMode packet. See above
3996 under "New remote packets."
3998 set remote query-attached-packet
3999 show remote query-attached-packet
4000 Control use of remote protocol `qAttached' (query-attached) packet.
4002 set remote read-siginfo-object
4003 show remote read-siginfo-object
4004 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
4007 set remote write-siginfo-object
4008 show remote write-siginfo-object
4009 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
4012 set remote reverse-continue
4013 show remote reverse-continue
4014 Control use of remote protocol 'bc' (reverse-continue) packet.
4016 set remote reverse-step
4017 show remote reverse-step
4018 Control use of remote protocol 'bs' (reverse-step) packet.
4020 set displaced-stepping
4021 show displaced-stepping
4022 Control displaced stepping mode. Displaced stepping is a way to
4023 single-step over breakpoints without removing them from the debuggee.
4024 Also known as "out-of-line single-stepping".
4027 show debug displaced
4028 Control display of debugging info for displaced stepping.
4030 maint set internal-error
4031 maint show internal-error
4032 Control what GDB does when an internal error is detected.
4034 maint set internal-warning
4035 maint show internal-warning
4036 Control what GDB does when an internal warning is detected.
4041 Use a wrapper program to launch programs for debugging.
4043 set multiple-symbols (all|ask|cancel)
4044 show multiple-symbols
4045 The value of this variable can be changed to adjust the debugger behavior
4046 when an expression or a breakpoint location contains an ambiguous symbol
4047 name (an overloaded function name, for instance).
4049 set breakpoint always-inserted
4050 show breakpoint always-inserted
4051 Keep breakpoints always inserted in the target, as opposed to inserting
4052 them when resuming the target, and removing them when the target stops.
4053 This option can improve debugger performance on slow remote targets.
4055 set arm fallback-mode (arm|thumb|auto)
4056 show arm fallback-mode
4057 set arm force-mode (arm|thumb|auto)
4059 These commands control how ARM GDB determines whether instructions
4060 are ARM or Thumb. The default for both settings is auto, which uses
4061 the current CPSR value for instructions without symbols; previous
4062 versions of GDB behaved as if "set arm fallback-mode arm".
4064 set disable-randomization
4065 show disable-randomization
4066 Standalone programs run with the virtual address space randomization enabled
4067 by default on some platforms. This option keeps the addresses stable across
4068 multiple debugging sessions.
4072 Control whether other threads are stopped or not when some thread hits
4077 Requests that asynchronous execution is enabled in the target, if available.
4078 In this case, it's possible to resume target in the background, and interact
4079 with GDB while the target is running. "show target-async" displays the
4080 current state of asynchronous execution of the target.
4082 set target-wide-charset
4083 show target-wide-charset
4084 The target-wide-charset is the name of the character set that GDB
4085 uses when printing characters whose type is wchar_t.
4087 set tcp auto-retry (on|off)
4089 set tcp connect-timeout
4090 show tcp connect-timeout
4091 These commands allow GDB to retry failed TCP connections to a remote stub
4092 with a specified timeout period; this is useful if the stub is launched
4093 in parallel with GDB but may not be ready to accept connections immediately.
4095 set libthread-db-search-path
4096 show libthread-db-search-path
4097 Control list of directories which GDB will search for appropriate
4100 set schedule-multiple (on|off)
4101 show schedule-multiple
4102 Allow GDB to resume all threads of all processes or only threads of
4103 the current process.
4107 Use more aggressive caching for accesses to the stack. This improves
4108 performance of remote debugging (particularly backtraces) without
4109 affecting correctness.
4111 set interactive-mode (on|off|auto)
4112 show interactive-mode
4113 Control whether GDB runs in interactive mode (on) or not (off).
4114 When in interactive mode, GDB waits for the user to answer all
4115 queries. Otherwise, GDB does not wait and assumes the default
4116 answer. When set to auto (the default), GDB determines which
4117 mode to use based on the stdin settings.
4122 For program forks, this is replaced by the new more generic `info
4123 inferiors' command. To list checkpoints, you can still use the
4124 `info checkpoints' command, which was an alias for the `info forks'
4128 Replaced by the new `inferior' command. To switch between
4129 checkpoints, you can still use the `restart' command, which was an
4130 alias for the `fork' command.
4133 This is removed, since some targets don't have a notion of
4134 processes. To switch between processes, you can still use the
4135 `inferior' command using GDB's own inferior number.
4138 For program forks, this is replaced by the new more generic `kill
4139 inferior' command. To delete a checkpoint, you can still use the
4140 `delete checkpoint' command, which was an alias for the `delete
4144 For program forks, this is replaced by the new more generic `detach
4145 inferior' command. To detach a checkpoint, you can still use the
4146 `detach checkpoint' command, which was an alias for the `detach
4149 * New native configurations
4151 x86/x86_64 Darwin i[34567]86-*-darwin*
4153 x86_64 MinGW x86_64-*-mingw*
4157 Lattice Mico32 lm32-*
4158 x86 DICOS i[34567]86-*-dicos*
4159 x86_64 DICOS x86_64-*-dicos*
4162 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4163 (mingw32ce) debugging.
4169 These commands were actually not implemented on any target.
4171 *** Changes in GDB 6.8
4173 * New native configurations
4175 NetBSD/hppa hppa*-*netbsd*
4176 Xtensa GNU/Linux xtensa*-*-linux*
4180 NetBSD/hppa hppa*-*-netbsd*
4181 Xtensa GNU/Lunux xtensa*-*-linux*
4183 * Change in command line behavior -- corefiles vs. process ids.
4185 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4186 attaching to process NUMBER fails, GDB no longer attempts to open a
4187 core file named NUMBER. Attaching to a program using the -c option
4188 is no longer supported. Instead, use the '-p' or '--pid' options.
4190 * GDB can now be built as a native debugger for debugging Windows x86
4191 (mingw32) Portable Executable (PE) programs.
4193 * Pending breakpoints no longer change their number when their address
4196 * GDB now supports breakpoints with multiple locations,
4197 including breakpoints on C++ constructors, inside C++ templates,
4198 and in inlined functions.
4200 * GDB's ability to debug optimized code has been improved. GDB more
4201 accurately identifies function bodies and lexical blocks that occupy
4202 more than one contiguous range of addresses.
4204 * Target descriptions can now describe registers for PowerPC.
4206 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4207 registers on PowerPC targets.
4209 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4210 targets even when the libthread_db library is not available.
4212 * The GDB remote stub, gdbserver, now supports the new file transfer
4213 commands (remote put, remote get, and remote delete).
4215 * The GDB remote stub, gdbserver, now supports run and attach in
4216 extended-remote mode.
4218 * hppa*64*-*-hpux11* target broken
4219 The debugger is unable to start a program and fails with the following
4220 error: "Error trying to get information about dynamic linker".
4221 The gdb-6.7 release is also affected.
4223 * GDB now supports the --enable-targets= configure option to allow
4224 building a single GDB executable that supports multiple remote
4225 target architectures.
4227 * GDB now supports debugging C and C++ programs which use the
4228 Decimal Floating Point extension. In addition, the PowerPC target
4229 now has a set of pseudo-registers to inspect decimal float values
4230 stored in two consecutive float registers.
4232 * The -break-insert MI command can optionally create pending
4235 * Improved support for debugging Ada
4236 Many improvements to the Ada language support have been made. These
4238 - Better support for Ada2005 interface types
4239 - Improved handling of arrays and slices in general
4240 - Better support for Taft-amendment types
4241 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4243 - Improved command completion in Ada
4246 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4251 set print frame-arguments (all|scalars|none)
4252 show print frame-arguments
4253 The value of this variable can be changed to control which argument
4254 values should be printed by the debugger when displaying a frame.
4259 Transfer files to and from a remote target, and delete remote files.
4266 Transfer files to and from a remote target, and delete remote files.
4268 * New remote packets
4275 Open, close, read, write, and delete files on the remote system.
4278 Attach to an existing process on the remote system, in extended-remote
4282 Run a new process on the remote system, in extended-remote mode.
4284 *** Changes in GDB 6.7
4286 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4287 bfd, libiberty and opcodes, as revealed by static analysis donated by
4288 Coverity, Inc. (http://scan.coverity.com).
4290 * When looking up multiply-defined global symbols, GDB will now prefer the
4291 symbol definition in the current shared library if it was built using the
4292 -Bsymbolic linker option.
4294 * When the Text User Interface (TUI) is not configured, GDB will now
4295 recognize the -tui command-line option and print a message that the TUI
4298 * The GDB remote stub, gdbserver, now has lower overhead for high
4299 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4301 * GDB for MIPS targets now autodetects whether a remote target provides
4302 32-bit or 64-bit register values.
4304 * Support for C++ member pointers has been improved.
4306 * GDB now understands XML target descriptions, which specify the
4307 target's overall architecture. GDB can read a description from
4308 a local file or over the remote serial protocol.
4310 * Vectors of single-byte data use a new integer type which is not
4311 automatically displayed as character or string data.
4313 * The /s format now works with the print command. It displays
4314 arrays of single-byte integers and pointers to single-byte integers
4317 * Target descriptions can now describe target-specific registers,
4318 for architectures which have implemented the support (currently
4319 only ARM, M68K, and MIPS).
4321 * GDB and the GDB remote stub, gdbserver, now support the XScale
4324 * The GDB remote stub, gdbserver, has been updated to support
4325 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4326 has been rewritten to use the standard GDB remote protocol.
4328 * GDB can now step into C++ functions which are called through thunks.
4330 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4332 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4333 layout. It also supports a TextSeg= and DataSeg= response when only
4334 segment base addresses (rather than offsets) are available.
4336 * The /i format now outputs any trailing branch delay slot instructions
4337 immediately following the last instruction within the count specified.
4339 * The GDB remote protocol "T" stop reply packet now supports a
4340 "library" response. Combined with the new "qXfer:libraries:read"
4341 packet, this response allows GDB to debug shared libraries on targets
4342 where the operating system manages the list of loaded libraries (e.g.
4343 Windows and SymbianOS).
4345 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4346 (DLLs) on Windows and Windows CE targets.
4348 * GDB now supports a faster verification that a .debug file matches its binary
4349 according to its build-id signature, if the signature is present.
4355 Enable or disable hardware flow control (RTS/CTS) on the serial port
4356 when debugging using remote targets.
4358 set mem inaccessible-by-default
4359 show mem inaccessible-by-default
4360 If the target supplies a memory map, for instance via the remote
4361 protocol's "qXfer:memory-map:read" packet, setting this variable
4362 prevents GDB from accessing memory outside the memory map. This
4363 is useful for targets with memory mapped registers or which react
4364 badly to accesses of unmapped address space.
4366 set breakpoint auto-hw
4367 show breakpoint auto-hw
4368 If the target supplies a memory map, for instance via the remote
4369 protocol's "qXfer:memory-map:read" packet, setting this variable
4370 lets GDB use hardware breakpoints automatically for memory regions
4371 where it can not use software breakpoints. This covers both the
4372 "break" command and internal breakpoints used for other commands
4373 including "next" and "finish".
4376 catch exception unhandled
4377 Stop the program execution when Ada exceptions are raised.
4380 Stop the program execution when an Ada assertion failed.
4384 Set an alternate system root for target files. This is a more
4385 general version of "set solib-absolute-prefix", which is now
4386 an alias to "set sysroot".
4389 Provide extended SPU facility status information. This set of
4390 commands is available only when debugging the Cell/B.E. SPU
4393 * New native configurations
4395 OpenBSD/sh sh*-*openbsd*
4398 unset tdesc filename
4400 Use the specified local file as an XML target description, and do
4401 not query the target for its built-in description.
4405 OpenBSD/sh sh*-*-openbsd*
4406 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4407 Toshiba Media Processor mep-elf
4409 * New remote packets
4412 Ignore the specified signals; pass them directly to the debugged program
4413 without stopping other threads or reporting them to GDB.
4415 qXfer:features:read:
4416 Read an XML target description from the target, which describes its
4421 Read or write contents of an spufs file on the target system. These
4422 packets are available only on the Cell/B.E. SPU architecture.
4424 qXfer:libraries:read:
4425 Report the loaded shared libraries. Combined with new "T" packet
4426 response, this packet allows GDB to debug shared libraries on
4427 targets where the operating system manages the list of loaded
4428 libraries (e.g. Windows and SymbianOS).
4432 Support for these obsolete configurations has been removed.
4440 i[34567]86-*-lynxos*
4441 i[34567]86-*-netware*
4442 i[34567]86-*-sco3.2v5*
4443 i[34567]86-*-sco3.2v4*
4445 i[34567]86-*-sysv4.2*
4448 i[34567]86-*-unixware2*
4449 i[34567]86-*-unixware*
4458 * Other removed features
4465 Various m68k-only ROM monitors.
4472 Various Renesas ROM monitors and debugging interfaces for SH and
4477 Support for a Macraigor serial interface to on-chip debugging.
4478 GDB does not directly support the newer parallel or USB
4483 A debug information format. The predecessor to DWARF 2 and
4484 DWARF 3, which are still supported.
4486 Support for the HP aCC compiler on HP-UX/PA-RISC
4488 SOM-encapsulated symbolic debugging information, automatic
4489 invocation of pxdb, and the aCC custom C++ ABI. This does not
4490 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4491 with aCC can still be debugged on an assembly level.
4493 MIPS ".pdr" sections
4495 A MIPS-specific format used to describe stack frame layout
4496 in debugging information.
4500 GDB could work with an older version of Guile to debug
4501 the interpreter and Scheme programs running in it.
4503 set mips stack-arg-size
4504 set mips saved-gpreg-size
4506 Use "set mips abi" to control parameter passing for MIPS.
4508 *** Changes in GDB 6.6
4513 Cell Broadband Engine SPU spu-elf
4515 * GDB can now be configured as a cross-debugger targeting native Windows
4516 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4517 running on a Windows system over TCP/IP to debug Windows programs.
4519 * The GDB remote stub, gdbserver, has been updated to support Windows and
4520 Cygwin debugging. Both single-threaded and multi-threaded programs are
4523 * The "set trust-readonly-sections" command works again. This command was
4524 broken in GDB 6.3, 6.4, and 6.5.
4526 * The "load" command now supports writing to flash memory, if the remote
4527 stub provides the required support.
4529 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4530 longer requires symbolic debug information (e.g. DWARF-2).
4535 unset substitute-path
4536 show substitute-path
4537 Manage a list of substitution rules that GDB uses to rewrite the name
4538 of the directories where the sources are located. This can be useful
4539 for instance when the sources were moved to a different location
4540 between compilation and debugging.
4544 Print each CLI command as it is executed. Each command is prefixed with
4545 a number of `+' symbols representing the nesting depth.
4546 The source command now has a `-v' option to enable the same feature.
4550 The ARM Demon monitor support (RDP protocol, "target rdp").
4552 Kernel Object Display, an embedded debugging feature which only worked with
4553 an obsolete version of Cisco IOS.
4555 The 'set download-write-size' and 'show download-write-size' commands.
4557 * New remote packets
4560 Tell a stub about GDB client features, and request remote target features.
4561 The first feature implemented is PacketSize, which allows the target to
4562 specify the size of packets it can handle - to minimize the number of
4563 packets required and improve performance when connected to a remote
4567 Fetch an OS auxilliary vector from the remote stub. This packet is a
4568 more efficient replacement for qPart:auxv:read.
4570 qXfer:memory-map:read:
4571 Fetch a memory map from the remote stub, including information about
4572 RAM, ROM, and flash memory devices.
4577 Erase and program a flash memory device.
4579 * Removed remote packets
4582 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4583 used it, and only gdbserver implemented it.
4585 *** Changes in GDB 6.5
4589 Renesas M32C/M16C m32c-elf
4591 Morpho Technologies ms1 ms1-elf
4595 init-if-undefined Initialize a convenience variable, but
4596 only if it doesn't already have a value.
4598 The following commands are presently only implemented for native GNU/Linux:
4600 checkpoint Save a snapshot of the program state.
4602 restart <n> Return the program state to a
4603 previously saved state.
4605 info checkpoints List currently saved checkpoints.
4607 delete-checkpoint <n> Delete a previously saved checkpoint.
4609 set|show detach-on-fork Tell gdb whether to detach from a newly
4610 forked process, or to keep debugging it.
4612 info forks List forks of the user program that
4613 are available to be debugged.
4615 fork <n> Switch to debugging one of several
4616 forks of the user program that are
4617 available to be debugged.
4619 delete-fork <n> Delete a fork from the list of forks
4620 that are available to be debugged (and
4621 kill the forked process).
4623 detach-fork <n> Delete a fork from the list of forks
4624 that are available to be debugged (and
4625 allow the process to continue).
4629 Morpho Technologies ms2 ms1-elf
4631 * Improved Windows host support
4633 GDB now builds as a cross debugger hosted on i686-mingw32, including
4634 native console support, and remote communications using either
4635 network sockets or serial ports.
4637 * Improved Modula-2 language support
4639 GDB can now print most types in the Modula-2 syntax. This includes:
4640 basic types, set types, record types, enumerated types, range types,
4641 pointer types and ARRAY types. Procedure var parameters are correctly
4642 printed and hexadecimal addresses and character constants are also
4643 written in the Modula-2 syntax. Best results can be obtained by using
4644 GNU Modula-2 together with the -gdwarf-2 command line option.
4648 The ARM rdi-share module.
4650 The Netware NLM debug server.
4652 *** Changes in GDB 6.4
4654 * New native configurations
4656 OpenBSD/arm arm*-*-openbsd*
4657 OpenBSD/mips64 mips64-*-openbsd*
4661 Morpho Technologies ms1 ms1-elf
4663 * New command line options
4665 --batch-silent As for --batch, but totally silent.
4666 --return-child-result The debugger will exist with the same value
4667 the child (debugged) program exited with.
4668 --eval-command COMMAND, -ex COMMAND
4669 Execute a single GDB CLI command. This may be
4670 specified multiple times and in conjunction
4671 with the --command (-x) option.
4673 * Deprecated commands removed
4675 The following commands, that were deprecated in 2000, have been
4679 set|show arm disassembly-flavor set|show arm disassembler
4680 othernames set arm disassembler
4681 set|show remotedebug set|show debug remote
4682 set|show archdebug set|show debug arch
4683 set|show eventdebug set|show debug event
4686 * New BSD user-level threads support
4688 It is now possible to debug programs using the user-level threads
4689 library on OpenBSD and FreeBSD. Currently supported (target)
4692 FreeBSD/amd64 x86_64-*-freebsd*
4693 FreeBSD/i386 i386-*-freebsd*
4694 OpenBSD/i386 i386-*-openbsd*
4696 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4697 are not yet supported.
4699 * New support for Matsushita MN10300 w/sim added
4700 (Work in progress). mn10300-elf.
4702 * REMOVED configurations and files
4704 VxWorks and the XDR protocol *-*-vxworks
4705 Motorola MCORE mcore-*-*
4706 National Semiconductor NS32000 ns32k-*-*
4708 * New "set print array-indexes" command
4710 After turning this setting "on", GDB prints the index of each element
4711 when displaying arrays. The default is "off" to preserve the previous
4714 * VAX floating point support
4716 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4718 * User-defined command support
4720 In addition to using $arg0..$arg9 for argument passing, it is now possible
4721 to use $argc to determine now many arguments have been passed. See the
4722 section on user-defined commands in the user manual for more information.
4724 *** Changes in GDB 6.3:
4726 * New command line option
4728 GDB now accepts -l followed by a number to set the timeout for remote
4731 * GDB works with GCC -feliminate-dwarf2-dups
4733 GDB now supports a more compact representation of DWARF-2 debug
4734 information using DW_FORM_ref_addr references. These are produced
4735 by GCC with the option -feliminate-dwarf2-dups and also by some
4736 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4737 to use -feliminate-dwarf2-dups.
4739 * Internationalization
4741 When supported by the host system, GDB will be built with
4742 internationalization (libintl). The task of marking up the sources is
4743 continued, we're looking forward to our first translation.
4747 Initial support for debugging programs compiled with the GNAT
4748 implementation of the Ada programming language has been integrated
4749 into GDB. In this release, support is limited to expression evaluation.
4751 * New native configurations
4753 GNU/Linux/m32r m32r-*-linux-gnu
4757 GDB's remote protocol now includes support for the 'p' packet. This
4758 packet is used to fetch individual registers from a remote inferior.
4760 * END-OF-LIFE registers[] compatibility module
4762 GDB's internal register infrastructure has been completely rewritten.
4763 The new infrastructure making possible the implementation of key new
4764 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4767 GDB 6.3 will be the last release to include the the registers[]
4768 compatibility module that allowed out-of-date configurations to
4769 continue to work. This change directly impacts the following
4779 powerpc bdm protocol
4781 Unless there is activity to revive these configurations, they will be
4782 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4784 * OBSOLETE configurations and files
4786 Configurations that have been declared obsolete in this release have
4787 been commented out. Unless there is activity to revive these
4788 configurations, the next release of GDB will have their sources
4789 permanently REMOVED.
4798 *** Changes in GDB 6.2.1:
4800 * MIPS `break main; run' gave an heuristic-fence-post warning
4802 When attempting to run even a simple program, a warning about
4803 heuristic-fence-post being hit would be reported. This problem has
4806 * MIPS IRIX 'long double' crashed GDB
4808 When examining a long double variable, GDB would get a segmentation
4809 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4810 IRIX long double values).
4814 A bug in the VAX stack code was causing problems with the "next"
4815 command. This problem has been fixed.
4817 *** Changes in GDB 6.2:
4819 * Fix for ``many threads''
4821 On GNU/Linux systems that use the NPTL threads library, a program
4822 rapidly creating and deleting threads would confuse GDB leading to the
4825 ptrace: No such process.
4826 thread_db_get_info: cannot get thread info: generic error
4828 This problem has been fixed.
4830 * "-async" and "-noasync" options removed.
4832 Support for the broken "-noasync" option has been removed (it caused
4835 * New ``start'' command.
4837 This command runs the program until the begining of the main procedure.
4839 * New BSD Kernel Data Access Library (libkvm) interface
4841 Using ``target kvm'' it is now possible to debug kernel core dumps and
4842 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4843 platforms. Currently supported (native-only) configurations are:
4845 FreeBSD/amd64 x86_64-*-freebsd*
4846 FreeBSD/i386 i?86-*-freebsd*
4847 NetBSD/i386 i?86-*-netbsd*
4848 NetBSD/m68k m68*-*-netbsd*
4849 NetBSD/sparc sparc-*-netbsd*
4850 OpenBSD/amd64 x86_64-*-openbsd*
4851 OpenBSD/i386 i?86-*-openbsd*
4852 OpenBSD/m68k m68*-openbsd*
4853 OpenBSD/sparc sparc-*-openbsd*
4855 * Signal trampoline code overhauled
4857 Many generic problems with GDB's signal handling code have been fixed.
4858 These include: backtraces through non-contiguous stacks; recognition
4859 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4860 call; backtrace through a signal trampoline; step into and out of
4861 signal handlers; and single-stepping in the signal trampoline.
4863 Please note that kernel bugs are a limiting factor here. These
4864 features have been shown to work on an s390 GNU/Linux system that
4865 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4867 * Cygwin support for DWARF 2 added.
4869 * New native configurations
4871 GNU/Linux/hppa hppa*-*-linux*
4872 OpenBSD/hppa hppa*-*-openbsd*
4873 OpenBSD/m68k m68*-*-openbsd*
4874 OpenBSD/m88k m88*-*-openbsd*
4875 OpenBSD/powerpc powerpc-*-openbsd*
4876 NetBSD/vax vax-*-netbsd*
4877 OpenBSD/vax vax-*-openbsd*
4879 * END-OF-LIFE frame compatibility module
4881 GDB's internal frame infrastructure has been completely rewritten.
4882 The new infrastructure making it possible to support key new features
4883 including DWARF 2 Call Frame Information. To aid in the task of
4884 migrating old configurations to this new infrastructure, a
4885 compatibility module, that allowed old configurations to continue to
4886 work, was also included.
4888 GDB 6.2 will be the last release to include this frame compatibility
4889 module. This change directly impacts the following configurations:
4899 Unless there is activity to revive these configurations, they will be
4900 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4902 * REMOVED configurations and files
4904 Sun 3, running SunOS 3 m68*-*-sunos3*
4905 Sun 3, running SunOS 4 m68*-*-sunos4*
4906 Sun 2, running SunOS 3 m68000-*-sunos3*
4907 Sun 2, running SunOS 4 m68000-*-sunos4*
4908 Motorola 680x0 running LynxOS m68*-*-lynxos*
4909 AT&T 3b1/Unix pc m68*-att-*
4910 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4911 decstation mips-dec-* mips-little-*
4912 riscos mips-*-riscos* mips-*-sysv*
4913 sonymips mips-sony-*
4914 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4916 *** Changes in GDB 6.1.1:
4918 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4920 The TUI (Text-mode User Interface) is now built as part of a default
4921 GDB configuration. It is enabled by either selecting the TUI with the
4922 command line option "-i=tui" or by running the separate "gdbtui"
4923 program. For more information on the TUI, see the manual "Debugging
4926 * Pending breakpoint support (also included in GDB 6.1)
4928 Support has been added to allow you to specify breakpoints in shared
4929 libraries that have not yet been loaded. If a breakpoint location
4930 cannot be found, and the "breakpoint pending" option is set to auto,
4931 GDB queries you if you wish to make the breakpoint pending on a future
4932 shared-library load. If and when GDB resolves the breakpoint symbol,
4933 the pending breakpoint is removed as one or more regular breakpoints
4936 Pending breakpoints are very useful for GCJ Java debugging.
4938 * Fixed ISO-C build problems
4940 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4941 non ISO-C code that stopped them being built using a more strict ISO-C
4942 compiler (e.g., IBM's C compiler).
4944 * Fixed build problem on IRIX 5
4946 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4947 wasn't able to compile compile on an IRIX 5 system.
4949 * Added execute permission to gdb/gdbserver/configure
4951 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4952 permission. This bug would cause configure to fail on a number of
4953 systems (Solaris, IRIX). Ref: server/519.
4955 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4957 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4958 has been updated to use constant array sizes.
4960 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4962 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4963 its generated DWARF Call Frame Info. This encoding was causing GDB to
4964 panic, that panic has been fixed. Ref: gdb/1628.
4966 * Fixed a problem when examining parameters in shared library code.
4968 When examining parameters in optimized shared library code generated
4969 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4970 not available''. GDB now correctly displays the variable's value.
4972 *** Changes in GDB 6.1:
4974 * Removed --with-mmalloc
4976 Support for the mmalloc memory manager has been removed, as it
4977 conflicted with the internal gdb byte cache.
4979 * Changes in AMD64 configurations
4981 The AMD64 target now includes the %cs and %ss registers. As a result
4982 the AMD64 remote protocol has changed; this affects the floating-point
4983 and SSE registers. If you rely on those registers for your debugging,
4984 you should upgrade gdbserver on the remote side.
4986 * Revised SPARC target
4988 The SPARC target has been completely revised, incorporating the
4989 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4990 support for LynxOS and SunOS 4 has been dropped. Calling functions
4991 from within GDB on operating systems with a non-executable stack
4992 (Solaris, OpenBSD) now works.
4996 GDB has a new C++ demangler which does a better job on the mangled
4997 names generated by current versions of g++. It also runs faster, so
4998 with this and other changes gdb should now start faster on large C++
5001 * DWARF 2 Location Expressions
5003 GDB support for location expressions has been extended to support function
5004 arguments and frame bases. Older versions of GDB could crash when they
5007 * C++ nested types and namespaces
5009 GDB's support for nested types and namespaces in C++ has been
5010 improved, especially if you use the DWARF 2 debugging format. (This
5011 is the default for recent versions of GCC on most platforms.)
5012 Specifically, if you have a class "Inner" defined within a class or
5013 namespace "Outer", then GDB realizes that the class's name is
5014 "Outer::Inner", not simply "Inner". This should greatly reduce the
5015 frequency of complaints about not finding RTTI symbols. In addition,
5016 if you are stopped at inside of a function defined within a namespace,
5017 GDB modifies its name lookup accordingly.
5019 * New native configurations
5021 NetBSD/amd64 x86_64-*-netbsd*
5022 OpenBSD/amd64 x86_64-*-openbsd*
5023 OpenBSD/alpha alpha*-*-openbsd*
5024 OpenBSD/sparc sparc-*-openbsd*
5025 OpenBSD/sparc64 sparc64-*-openbsd*
5027 * New debugging protocols
5029 M32R with SDI protocol m32r-*-elf*
5031 * "set prompt-escape-char" command deleted.
5033 The command "set prompt-escape-char" has been deleted. This command,
5034 and its very obscure effet on GDB's prompt, was never documented,
5035 tested, nor mentioned in the NEWS file.
5037 * OBSOLETE configurations and files
5039 Configurations that have been declared obsolete in this release have
5040 been commented out. Unless there is activity to revive these
5041 configurations, the next release of GDB will have their sources
5042 permanently REMOVED.
5044 Sun 3, running SunOS 3 m68*-*-sunos3*
5045 Sun 3, running SunOS 4 m68*-*-sunos4*
5046 Sun 2, running SunOS 3 m68000-*-sunos3*
5047 Sun 2, running SunOS 4 m68000-*-sunos4*
5048 Motorola 680x0 running LynxOS m68*-*-lynxos*
5049 AT&T 3b1/Unix pc m68*-att-*
5050 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
5051 decstation mips-dec-* mips-little-*
5052 riscos mips-*-riscos* mips-*-sysv*
5053 sonymips mips-sony-*
5054 sysv mips*-*-sysv4* (IRIX 5/6 not included)
5056 * REMOVED configurations and files
5058 SGI Irix-4.x mips-sgi-irix4 or iris4
5059 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
5060 Z8000 simulator z8k-zilog-none or z8ksim
5061 Matsushita MN10200 w/simulator mn10200-*-*
5062 H8/500 simulator h8500-hitachi-hms or h8500hms
5063 HP/PA running BSD hppa*-*-bsd*
5064 HP/PA running OSF/1 hppa*-*-osf*
5065 HP/PA Pro target hppa*-*-pro*
5066 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5067 386BSD i[3456]86-*-bsd*
5068 Sequent family i[3456]86-sequent-sysv4*
5069 i[3456]86-sequent-sysv*
5070 i[3456]86-sequent-bsd*
5071 SPARC running LynxOS sparc-*-lynxos*
5072 SPARC running SunOS 4 sparc-*-sunos4*
5073 Tsqware Sparclet sparclet-*-*
5074 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5076 *** Changes in GDB 6.0:
5080 Support for debugging the Objective-C programming language has been
5081 integrated into GDB.
5083 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
5085 DWARF 2's Call Frame Information makes available compiler generated
5086 information that more exactly describes the program's run-time stack.
5087 By using this information, GDB is able to provide more robust stack
5090 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5091 have been updated to use a new backtrace mechanism which includes
5092 DWARF 2 CFI support.
5096 GDB's remote protocol has been extended to include support for hosted
5097 file I/O (where the remote target uses GDB's file system). See GDB's
5098 remote protocol documentation for details.
5100 * All targets using the new architecture framework.
5102 All of GDB's targets have been updated to use the new internal
5103 architecture framework. The way is now open for future GDB releases
5104 to include cross-architecture native debugging support (i386 on amd64,
5107 * GNU/Linux's Thread Local Storage (TLS)
5109 GDB now includes support for for the GNU/Linux implementation of
5110 per-thread variables.
5112 * GNU/Linux's Native POSIX Thread Library (NPTL)
5114 GDB's thread code has been updated to work with either the new
5115 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5117 * Separate debug info.
5119 GDB, in conjunction with BINUTILS, now supports a mechanism for
5120 automatically loading debug information from a separate file. Instead
5121 of shipping full debug and non-debug versions of system libraries,
5122 system integrators can now instead ship just the stripped libraries
5123 and optional debug files.
5125 * DWARF 2 Location Expressions
5127 DWARF 2 Location Expressions allow the compiler to more completely
5128 describe the location of variables (even in optimized code) to the
5131 GDB now includes preliminary support for location expressions (support
5132 for DW_OP_piece is still missing).
5136 A number of long standing bugs that caused GDB to die while starting a
5137 Java application have been fixed. GDB's Java support is now
5138 considered "useable".
5140 * GNU/Linux support for fork, vfork, and exec.
5142 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5143 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5146 * GDB supports logging output to a file
5148 There are two new commands, "set logging" and "show logging", which can be
5149 used to capture GDB's output to a file.
5151 * The meaning of "detach" has changed for gdbserver
5153 The "detach" command will now resume the application, as documented. To
5154 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5157 * d10v, m68hc11 `regs' command deprecated
5159 The `info registers' command has been updated so that it displays the
5160 registers using a format identical to the old `regs' command.
5164 A new command, "maint set profile on/off", has been added. This command can
5165 be used to enable or disable profiling while running GDB, to profile a
5166 session or a set of commands. In addition there is a new configure switch,
5167 "--enable-profiling", which will cause GDB to be compiled with profiling
5168 data, for more informative profiling results.
5170 * Default MI syntax changed to "mi2".
5172 The default MI (machine interface) syntax, enabled by the command line
5173 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5174 "mi1", can be enabled by specifying the option "-i=mi1".
5176 Support for the original "mi0" syntax (included in GDB 5.0) has been
5179 Fix for gdb/192: removed extraneous space when displaying frame level.
5180 Fix for gdb/672: update changelist is now output in mi list format.
5181 Fix for gdb/702: a -var-assign that updates the value now shows up
5182 in a subsequent -var-update.
5184 * New native configurations.
5186 FreeBSD/amd64 x86_64-*-freebsd*
5188 * Multi-arched targets.
5190 HP/PA HPUX11 hppa*-*-hpux*
5191 Renesas M32R/D w/simulator m32r-*-elf*
5193 * OBSOLETE configurations and files
5195 Configurations that have been declared obsolete in this release have
5196 been commented out. Unless there is activity to revive these
5197 configurations, the next release of GDB will have their sources
5198 permanently REMOVED.
5200 Z8000 simulator z8k-zilog-none or z8ksim
5201 Matsushita MN10200 w/simulator mn10200-*-*
5202 H8/500 simulator h8500-hitachi-hms or h8500hms
5203 HP/PA running BSD hppa*-*-bsd*
5204 HP/PA running OSF/1 hppa*-*-osf*
5205 HP/PA Pro target hppa*-*-pro*
5206 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5207 Sequent family i[3456]86-sequent-sysv4*
5208 i[3456]86-sequent-sysv*
5209 i[3456]86-sequent-bsd*
5210 Tsqware Sparclet sparclet-*-*
5211 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5213 * REMOVED configurations and files
5216 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5217 IBM AIX PS/2 i[3456]86-*-aix
5218 i386 running Mach 3.0 i[3456]86-*-mach3*
5219 i386 running Mach i[3456]86-*-mach*
5220 i386 running OSF/1 i[3456]86-*osf1mk*
5221 HP/Apollo 68k Family m68*-apollo*-sysv*,
5223 m68*-hp-bsd*, m68*-hp-hpux*
5224 Argonaut Risc Chip (ARC) arc-*-*
5225 Mitsubishi D30V d30v-*-*
5226 Fujitsu FR30 fr30-*-elf*
5227 OS/9000 i[34]86-*-os9k
5228 I960 with MON960 i960-*-coff
5230 * MIPS $fp behavior changed
5232 The convenience variable $fp, for the MIPS, now consistently returns
5233 the address of the current frame's base. Previously, depending on the
5234 context, $fp could refer to either $sp or the current frame's base
5235 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5236 The GNU Source-Level Debugger''.
5238 *** Changes in GDB 5.3:
5240 * GNU/Linux shared library multi-threaded performance improved.
5242 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5243 `/proc', in preference to `ptrace' for memory reads. This may result
5244 in an improvement in the start-up time of multi-threaded, shared
5245 library applications when run under GDB. One GDB user writes: ``loads
5246 shared libs like mad''.
5248 * ``gdbserver'' now supports multi-threaded applications on some targets
5250 Support for debugging multi-threaded applications which use
5251 the GNU/Linux LinuxThreads package has been added for
5252 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5253 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5255 * GDB now supports C/C++ preprocessor macros.
5257 GDB now expands preprocessor macro invocations in C/C++ expressions,
5258 and provides various commands for showing macro definitions and how
5261 The new command `macro expand EXPRESSION' expands any macro
5262 invocations in expression, and shows the result.
5264 The new command `show macro MACRO-NAME' shows the definition of the
5265 macro named MACRO-NAME, and where it was defined.
5267 Most compilers don't include information about macros in the debugging
5268 information by default. In GCC 3.1, for example, you need to compile
5269 your program with the options `-gdwarf-2 -g3'. If the macro
5270 information is present in the executable, GDB will read it.
5272 * Multi-arched targets.
5274 DEC Alpha (partial) alpha*-*-*
5275 DEC VAX (partial) vax-*-*
5277 National Semiconductor NS32000 (partial) ns32k-*-*
5278 Motorola 68000 (partial) m68k-*-*
5279 Motorola MCORE mcore-*-*
5283 Fujitsu FRV architecture added by Red Hat frv*-*-*
5286 * New native configurations
5288 Alpha NetBSD alpha*-*-netbsd*
5289 SH NetBSD sh*-*-netbsdelf*
5290 MIPS NetBSD mips*-*-netbsd*
5291 UltraSPARC NetBSD sparc64-*-netbsd*
5293 * OBSOLETE configurations and files
5295 Configurations that have been declared obsolete in this release have
5296 been commented out. Unless there is activity to revive these
5297 configurations, the next release of GDB will have their sources
5298 permanently REMOVED.
5300 Mitsubishi D30V d30v-*-*
5301 OS/9000 i[34]86-*-os9k
5302 IBM AIX PS/2 i[3456]86-*-aix
5303 Fujitsu FR30 fr30-*-elf*
5304 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5305 Argonaut Risc Chip (ARC) arc-*-*
5306 i386 running Mach 3.0 i[3456]86-*-mach3*
5307 i386 running Mach i[3456]86-*-mach*
5308 i386 running OSF/1 i[3456]86-*osf1mk*
5309 HP/Apollo 68k Family m68*-apollo*-sysv*,
5311 m68*-hp-bsd*, m68*-hp-hpux*
5312 I960 with MON960 i960-*-coff
5314 * OBSOLETE languages
5316 CHILL, a Pascal like language used by telecommunications companies.
5318 * REMOVED configurations and files
5320 AMD 29k family via UDI a29k-amd-udi, udi29k
5321 A29K VxWorks a29k-*-vxworks
5322 AMD 29000 embedded, using EBMON a29k-none-none
5323 AMD 29000 embedded with COFF a29k-none-coff
5324 AMD 29000 embedded with a.out a29k-none-aout
5326 testsuite/gdb.hp/gdb.threads-hp/ directory
5328 * New command "set max-user-call-depth <nnn>"
5330 This command allows the user to limit the call depth of user-defined
5331 commands. The default is 1024.
5333 * Changes in FreeBSD/i386 native debugging.
5335 Support for the "generate-core-file" has been added.
5337 * New commands "dump", "append", and "restore".
5339 These commands allow data to be copied from target memory
5340 to a bfd-format or binary file (dump and append), and back
5341 from a file into memory (restore).
5343 * Improved "next/step" support on multi-processor Alpha Tru64.
5345 The previous single-step mechanism could cause unpredictable problems,
5346 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5347 of a software single-step mechanism prevents this.
5349 *** Changes in GDB 5.2.1:
5357 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5358 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5359 Fix, by Joel Brobecker imported from mainline.
5361 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5362 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5363 Fix, by Fred Fish, imported from mainline.
5365 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5366 Surprisingly enough, it works now.
5367 By Michal Ludvig, imported from mainline.
5369 i386 hardware watchpoint support:
5370 avoid misses on second run for some targets.
5371 By Pierre Muller, imported from mainline.
5373 *** Changes in GDB 5.2:
5375 * New command "set trust-readonly-sections on[off]".
5377 This command is a hint that tells gdb that read-only sections
5378 really are read-only (ie. that their contents will not change).
5379 In this mode, gdb will go to the object file rather than the
5380 target to read memory from read-only sections (such as ".text").
5381 This can be a significant performance improvement on some
5382 (notably embedded) targets.
5384 * New command "generate-core-file" (or "gcore").
5386 This new gdb command allows the user to drop a core file of the child
5387 process state at any time. So far it's been implemented only for
5388 GNU/Linux and Solaris, but should be relatively easily ported to other
5389 hosts. Argument is core file name (defaults to core.<pid>).
5391 * New command line option
5393 GDB now accepts --pid or -p followed by a process id.
5395 * Change in command line behavior -- corefiles vs. process ids.
5397 There is a subtle behavior in the way in which GDB handles
5398 command line arguments. The first non-flag argument is always
5399 a program to debug, but the second non-flag argument may either
5400 be a corefile or a process id. Previously, GDB would attempt to
5401 open the second argument as a corefile, and if that failed, would
5402 issue a superfluous error message and then attempt to attach it as
5403 a process. Now, if the second argument begins with a non-digit,
5404 it will be treated as a corefile. If it begins with a digit,
5405 GDB will attempt to attach it as a process, and if no such process
5406 is found, will then attempt to open it as a corefile.
5408 * Changes in ARM configurations.
5410 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5411 configuration is fully multi-arch.
5413 * New native configurations
5415 ARM NetBSD arm*-*-netbsd*
5416 x86 OpenBSD i[3456]86-*-openbsd*
5417 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5418 Sparc64 running FreeBSD sparc64-*-freebsd*
5422 Sanyo XStormy16 xstormy16-elf
5424 * OBSOLETE configurations and files
5426 Configurations that have been declared obsolete in this release have
5427 been commented out. Unless there is activity to revive these
5428 configurations, the next release of GDB will have their sources
5429 permanently REMOVED.
5431 AMD 29k family via UDI a29k-amd-udi, udi29k
5432 A29K VxWorks a29k-*-vxworks
5433 AMD 29000 embedded, using EBMON a29k-none-none
5434 AMD 29000 embedded with COFF a29k-none-coff
5435 AMD 29000 embedded with a.out a29k-none-aout
5437 testsuite/gdb.hp/gdb.threads-hp/ directory
5439 * REMOVED configurations and files
5441 TI TMS320C80 tic80-*-*
5443 PowerPC Solaris powerpcle-*-solaris*
5444 PowerPC Windows NT powerpcle-*-cygwin32
5445 PowerPC Netware powerpc-*-netware*
5446 Harris/CXUX m88k m88*-harris-cxux*
5447 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5448 ns32k-utek-sysv* ns32k-utek-*
5449 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5450 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5451 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5452 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5453 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5455 * Changes to command line processing
5457 The new `--args' feature can be used to specify command-line arguments
5458 for the inferior from gdb's command line.
5460 * Changes to key bindings
5462 There is a new `operate-and-get-next' function bound to `C-o'.
5464 *** Changes in GDB 5.1.1
5466 Fix compile problem on DJGPP.
5468 Fix a problem with floating-point registers on the i386 being
5471 Fix to stop GDB crashing on .debug_str debug info.
5473 Numerous documentation fixes.
5475 Numerous testsuite fixes.
5477 *** Changes in GDB 5.1:
5479 * New native configurations
5481 Alpha FreeBSD alpha*-*-freebsd*
5482 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5483 MIPS GNU/Linux mips*-*-linux*
5484 MIPS SGI Irix 6.x mips*-sgi-irix6*
5485 ia64 AIX ia64-*-aix*
5486 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5490 Motorola 68HC11 and 68HC12 m68hc11-elf
5492 UltraSparc running GNU/Linux sparc64-*-linux*
5494 * OBSOLETE configurations and files
5496 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5497 Harris/CXUX m88k m88*-harris-cxux*
5498 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5499 ns32k-utek-sysv* ns32k-utek-*
5500 TI TMS320C80 tic80-*-*
5502 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5503 PowerPC Solaris powerpcle-*-solaris*
5504 PowerPC Windows NT powerpcle-*-cygwin32
5505 PowerPC Netware powerpc-*-netware*
5506 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5507 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5508 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5509 Apple Macintosh (MPW) host N/A
5511 stuff.c (Program to stuff files into a specially prepared space in kdb)
5512 kdb-start.c (Main loop for the standalone kernel debugger)
5514 Configurations that have been declared obsolete in this release have
5515 been commented out. Unless there is activity to revive these
5516 configurations, the next release of GDB will have their sources
5517 permanently REMOVED.
5519 * REMOVED configurations and files
5521 Altos 3068 m68*-altos-*
5522 Convex c1-*-*, c2-*-*
5524 ARM RISCix arm-*-* (as host)
5528 * GDB has been converted to ISO C.
5530 GDB's source code has been converted to ISO C. In particular, the
5531 sources are fully protoized, and rely on standard headers being
5536 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5538 * The MI enabled by default.
5540 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5541 revised and enabled by default. Packages which use GDB as a debugging
5542 engine behind a UI or another front end are encouraged to switch to
5543 using the GDB/MI interface, instead of the old annotations interface
5544 which is now deprecated.
5546 * Support for debugging Pascal programs.
5548 GDB now includes support for debugging Pascal programs. The following
5549 main features are supported:
5551 - Pascal-specific data types such as sets;
5553 - automatic recognition of Pascal sources based on file-name
5556 - Pascal-style display of data types, variables, and functions;
5558 - a Pascal expression parser.
5560 However, some important features are not yet supported.
5562 - Pascal string operations are not supported at all;
5564 - there are some problems with boolean types;
5566 - Pascal type hexadecimal constants are not supported
5567 because they conflict with the internal variables format;
5569 - support for Pascal objects and classes is not full yet;
5571 - unlike Pascal, GDB is case-sensitive for symbol names.
5573 * Changes in completion.
5575 Commands such as `shell', `run' and `set args', which pass arguments
5576 to inferior programs, now complete on file names, similar to what
5577 users expect at the shell prompt.
5579 Commands which accept locations, such as `disassemble', `print',
5580 `breakpoint', `until', etc. now complete on filenames as well as
5581 program symbols. Thus, if you type "break foob TAB", and the source
5582 files linked into the programs include `foobar.c', that file name will
5583 be one of the candidates for completion. However, file names are not
5584 considered for completion after you typed a colon that delimits a file
5585 name from a name of a function in that file, as in "break foo.c:bar".
5587 `set demangle-style' completes on available demangling styles.
5589 * New platform-independent commands:
5591 It is now possible to define a post-hook for a command as well as a
5592 hook that runs before the command. For more details, see the
5593 documentation of `hookpost' in the GDB manual.
5595 * Changes in GNU/Linux native debugging.
5597 Support for debugging multi-threaded programs has been completely
5598 revised for all platforms except m68k and sparc. You can now debug as
5599 many threads as your system allows you to have.
5601 Attach/detach is supported for multi-threaded programs.
5603 Support for SSE registers was added for x86. This doesn't work for
5604 multi-threaded programs though.
5606 * Changes in MIPS configurations.
5608 Multi-arch support is enabled for all MIPS configurations.
5610 GDB can now be built as native debugger on SGI Irix 6.x systems for
5611 debugging n32 executables. (Debugging 64-bit executables is not yet
5614 * Unified support for hardware watchpoints in all x86 configurations.
5616 Most (if not all) native x86 configurations support hardware-assisted
5617 breakpoints and watchpoints in a unified manner. This support
5618 implements debug register sharing between watchpoints, which allows to
5619 put a virtually infinite number of watchpoints on the same address,
5620 and also supports watching regions up to 16 bytes with several debug
5623 The new maintenance command `maintenance show-debug-regs' toggles
5624 debugging print-outs in functions that insert, remove, and test
5625 watchpoints and hardware breakpoints.
5627 * Changes in the DJGPP native configuration.
5629 New command ``info dos sysinfo'' displays assorted information about
5630 the CPU, OS, memory, and DPMI server.
5632 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5633 display information about segment descriptors stored in GDT, LDT, and
5636 New commands ``info dos pde'' and ``info dos pte'' display entries
5637 from Page Directory and Page Tables (for now works with CWSDPMI only).
5638 New command ``info dos address-pte'' displays the Page Table entry for
5639 a given linear address.
5641 GDB can now pass command lines longer than 126 characters to the
5642 program being debugged (requires an update to the libdbg.a library
5643 which is part of the DJGPP development kit).
5645 DWARF2 debug info is now supported.
5647 It is now possible to `step' and `next' through calls to `longjmp'.
5649 * Changes in documentation.
5651 All GDB documentation was converted to GFDL, the GNU Free
5652 Documentation License.
5654 Tracepoints-related commands are now fully documented in the GDB
5657 TUI, the Text-mode User Interface, is now documented in the manual.
5659 Tracepoints-related commands are now fully documented in the GDB
5662 The "GDB Internals" manual now has an index. It also includes
5663 documentation of `ui_out' functions, GDB coding standards, x86
5664 hardware watchpoints, and memory region attributes.
5666 * GDB's version number moved to ``version.in''
5668 The Makefile variable VERSION has been replaced by the file
5669 ``version.in''. People creating GDB distributions should update the
5670 contents of this file.
5674 GUD support is now a standard part of the EMACS distribution.
5676 *** Changes in GDB 5.0:
5678 * Improved support for debugging FP programs on x86 targets
5680 Unified and much-improved support for debugging floating-point
5681 programs on all x86 targets. In particular, ``info float'' now
5682 displays the FP registers in the same format on all x86 targets, with
5683 greater level of detail.
5685 * Improvements and bugfixes in hardware-assisted watchpoints
5687 It is now possible to watch array elements, struct members, and
5688 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5689 on x86 targets no longer erroneously trigger when the address is
5692 * Improvements in the native DJGPP version of GDB
5694 The distribution now includes all the scripts and auxiliary files
5695 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5696 machines ``out of the box''.
5698 The DJGPP version can now debug programs that use signals. It is
5699 possible to catch signals that happened in the debuggee, deliver
5700 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5701 would kill the program being debugged.) Programs that hook hardware
5702 interrupts (keyboard, timer, etc.) can also be debugged.
5704 It is now possible to debug DJGPP programs that redirect their
5705 standard handles or switch them to raw (as opposed to cooked) mode, or
5706 even close them. The command ``run < foo > bar'' works as expected,
5707 and ``info terminal'' reports useful information about the debuggee's
5708 terminal, including raw/cooked mode, redirection, etc.
5710 The DJGPP version now uses termios functions for console I/O, which
5711 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5714 DOS-style file names with drive letters are now fully supported by
5717 It is now possible to debug DJGPP programs that switch their working
5718 directory. It is also possible to rerun the debuggee any number of
5719 times without restarting GDB; thus, you can use the same setup,
5720 breakpoints, etc. for many debugging sessions.
5722 * New native configurations
5724 ARM GNU/Linux arm*-*-linux*
5725 PowerPC GNU/Linux powerpc-*-linux*
5729 Motorola MCore mcore-*-*
5730 x86 VxWorks i[3456]86-*-vxworks*
5731 PowerPC VxWorks powerpc-*-vxworks*
5732 TI TMS320C80 tic80-*-*
5734 * OBSOLETE configurations
5736 Altos 3068 m68*-altos-*
5737 Convex c1-*-*, c2-*-*
5739 ARM RISCix arm-*-* (as host)
5742 Configurations that have been declared obsolete will be commented out,
5743 but the code will be left in place. If there is no activity to revive
5744 these configurations before the next release of GDB, the sources will
5745 be permanently REMOVED.
5747 * Gould support removed
5749 Support for the Gould PowerNode and NP1 has been removed.
5751 * New features for SVR4
5753 On SVR4 native platforms (such as Solaris), if you attach to a process
5754 without first loading a symbol file, GDB will now attempt to locate and
5755 load symbols from the running process's executable file.
5757 * Many C++ enhancements
5759 C++ support has been greatly improved. Overload resolution now works properly
5760 in almost all cases. RTTI support is on the way.
5762 * Remote targets can connect to a sub-program
5764 A popen(3) style serial-device has been added. This device starts a
5765 sub-process (such as a stand-alone simulator) and then communicates
5766 with that. The sub-program to run is specified using the syntax
5767 ``|<program> <args>'' vis:
5769 (gdb) set remotedebug 1
5770 (gdb) target extended-remote |mn10300-elf-sim program-args
5772 * MIPS 64 remote protocol
5774 A long standing bug in the mips64 remote protocol where by GDB
5775 expected certain 32 bit registers (ex SR) to be transfered as 32
5776 instead of 64 bits has been fixed.
5778 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5779 added to provide backward compatibility with older versions of GDB.
5781 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5783 The command ``set remotebinarydownload'' command has been replaced by
5784 ``set remote X-packet''. Other commands in ``set remote'' family
5785 include ``set remote P-packet''.
5787 * Breakpoint commands accept ranges.
5789 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5790 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5791 ``tracepoint passcount'' also accepts a range of tracepoints.
5793 * ``apropos'' command added.
5795 The ``apropos'' command searches through command names and
5796 documentation strings, printing out matches, making it much easier to
5797 try to find a command that does what you are looking for.
5801 A new machine oriented interface (MI) has been added to GDB. This
5802 interface is designed for debug environments running GDB as a separate
5803 process. This is part of the long term libGDB project. See the
5804 "GDB/MI" chapter of the GDB manual for further information. It can be
5805 enabled by configuring with:
5807 .../configure --enable-gdbmi
5809 *** Changes in GDB-4.18:
5811 * New native configurations
5813 HP-UX 10.20 hppa*-*-hpux10.20
5814 HP-UX 11.x hppa*-*-hpux11.0*
5815 M68K GNU/Linux m68*-*-linux*
5819 Fujitsu FR30 fr30-*-elf*
5820 Intel StrongARM strongarm-*-*
5821 Mitsubishi D30V d30v-*-*
5823 * OBSOLETE configurations
5825 Gould PowerNode, NP1 np1-*-*, pn-*-*
5827 Configurations that have been declared obsolete will be commented out,
5828 but the code will be left in place. If there is no activity to revive
5829 these configurations before the next release of GDB, the sources will
5830 be permanently REMOVED.
5834 As a compatibility experiment, GDB's source files buildsym.h and
5835 buildsym.c have been converted to pure standard C, no longer
5836 containing any K&R compatibility code. We believe that all systems in
5837 use today either come with a standard C compiler, or have a GCC port
5838 available. If this is not true, please report the affected
5839 configuration to bug-gdb@gnu.org immediately. See the README file for
5840 information about getting a standard C compiler if you don't have one
5845 GDB now uses readline 2.2.
5847 * set extension-language
5849 You can now control the mapping between filename extensions and source
5850 languages by using the `set extension-language' command. For instance,
5851 you can ask GDB to treat .c files as C++ by saying
5852 set extension-language .c c++
5853 The command `info extensions' lists all of the recognized extensions
5854 and their associated languages.
5856 * Setting processor type for PowerPC and RS/6000
5858 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5859 you can use the `set processor' command to specify what variant of the
5860 PowerPC family you are debugging. The command
5864 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5865 following PowerPC and RS6000 variants:
5867 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5868 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5870 403GC IBM PowerPC 403GC
5871 505 Motorola PowerPC 505
5872 860 Motorola PowerPC 860 or 850
5873 601 Motorola PowerPC 601
5874 602 Motorola PowerPC 602
5875 603 Motorola/IBM PowerPC 603 or 603e
5876 604 Motorola PowerPC 604 or 604e
5877 750 Motorola/IBM PowerPC 750 or 750
5879 At the moment, this command just tells GDB what to name the
5880 special-purpose processor registers. Since almost all the affected
5881 registers are inaccessible to user-level programs, this command is
5882 only useful for remote debugging in its present form.
5886 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5887 more extensive support for HP-UX. Added features include shared
5888 library support, kernel threads and hardware watchpoints for 11.00,
5889 support for HP's ANSI C and C++ compilers, and a compatibility mode
5890 for xdb and dbx commands.
5894 HP's donation includes the new concept of catchpoints, which is a
5895 generalization of the old catch command. On HP-UX, it is now possible
5896 to catch exec, fork, and vfork, as well as library loading.
5898 This means that the existing catch command has changed; its first
5899 argument now specifies the type of catch to be set up. See the
5900 output of "help catch" for a list of catchpoint types.
5902 * Debugging across forks
5904 On HP-UX, you can choose which process to debug when a fork() happens
5909 HP has donated a curses-based terminal user interface (TUI). To get
5910 it, build with --enable-tui. Although this can be enabled for any
5911 configuration, at present it only works for native HP debugging.
5913 * GDB remote protocol additions
5915 A new protocol packet 'X' that writes binary data is now available.
5916 Default behavior is to try 'X', then drop back to 'M' if the stub
5917 fails to respond. The settable variable `remotebinarydownload'
5918 allows explicit control over the use of 'X'.
5920 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5921 full 64-bit address. The command
5923 set remoteaddresssize 32
5925 can be used to revert to the old behaviour. For existing remote stubs
5926 the change should not be noticed, as the additional address information
5929 In order to assist in debugging stubs, you may use the maintenance
5930 command `packet' to send any text string to the stub. For instance,
5932 maint packet heythere
5934 sends the packet "$heythere#<checksum>". Note that it is very easy to
5935 disrupt a debugging session by sending the wrong packet at the wrong
5938 The compare-sections command allows you to compare section data on the
5939 target to what is in the executable file without uploading or
5940 downloading, by comparing CRC checksums.
5942 * Tracing can collect general expressions
5944 You may now collect general expressions at tracepoints. This requires
5945 further additions to the target-side stub; see tracepoint.c and
5946 doc/agentexpr.texi for further details.
5948 * mask-address variable for Mips
5950 For Mips targets, you may control the zeroing of the upper 32 bits of
5951 a 64-bit address by entering `set mask-address on'. This is mainly
5952 of interest to users of embedded R4xxx and R5xxx processors.
5954 * Higher serial baud rates
5956 GDB's serial code now allows you to specify baud rates 57600, 115200,
5957 230400, and 460800 baud. (Note that your host system may not be able
5958 to achieve all of these rates.)
5962 The i960 configuration now includes an initial implementation of a
5963 builtin simulator, contributed by Jim Wilson.
5966 *** Changes in GDB-4.17:
5968 * New native configurations
5970 Alpha GNU/Linux alpha*-*-linux*
5971 Unixware 2.x i[3456]86-unixware2*
5972 Irix 6.x mips*-sgi-irix6*
5973 PowerPC GNU/Linux powerpc-*-linux*
5974 PowerPC Solaris powerpcle-*-solaris*
5975 Sparc GNU/Linux sparc-*-linux*
5976 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5980 Argonaut Risc Chip (ARC) arc-*-*
5981 Hitachi H8/300S h8300*-*-*
5982 Matsushita MN10200 w/simulator mn10200-*-*
5983 Matsushita MN10300 w/simulator mn10300-*-*
5984 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5985 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5986 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5987 Mitsubishi D10V w/simulator d10v-*-*
5988 Mitsubishi M32R/D w/simulator m32r-*-elf*
5989 Tsqware Sparclet sparclet-*-*
5990 NEC V850 w/simulator v850-*-*
5992 * New debugging protocols
5994 ARM with RDI protocol arm*-*-*
5995 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5996 DDB and LSI variants of PMON protocol mips*-*-*
5997 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5998 PowerPC with SDS protocol powerpc{,le}-*-eabi
5999 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
6003 All configurations can now understand and use the DWARF 2 debugging
6004 format. The choice is automatic, if the symbol file contains DWARF 2
6009 GDB now includes basic Java language support. This support is
6010 only useful with Java compilers that produce native machine code.
6012 * solib-absolute-prefix and solib-search-path
6014 For SunOS and SVR4 shared libraries, you may now set the prefix for
6015 loading absolute shared library symbol files, and the search path for
6016 locating non-absolute shared library symbol files.
6018 * Live range splitting
6020 GDB can now effectively debug code for which GCC has performed live
6021 range splitting as part of its optimization. See gdb/doc/LRS for
6022 more details on the expected format of the stabs information.
6026 GDB's support for the GNU Hurd, including thread debugging, has been
6027 updated to work with current versions of the Hurd.
6031 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
6032 instruction set. ARM GDB automatically detects when Thumb
6033 instructions are in use, and adjusts disassembly and backtracing
6038 GDB's MIPS target configurations now handle the MIP16 16-bit
6043 GDB now includes support for overlays; if an executable has been
6044 linked such that multiple sections are based at the same address, GDB
6045 will decide which section to use for symbolic info. You can choose to
6046 control the decision manually, using overlay commands, or implement
6047 additional target-side support and use "overlay load-target" to bring
6048 in the overlay mapping. Do "help overlay" for more detail.
6052 The command "info symbol <address>" displays information about
6053 the symbol at the specified address.
6057 The standard remote protocol now includes an extension that allows
6058 asynchronous collection and display of trace data. This requires
6059 extensive support in the target-side debugging stub. Tracing mode
6060 includes a new interaction mode in GDB and new commands: see the
6061 file tracepoint.c for more details.
6065 Configurations for embedded MIPS now include a simulator contributed
6066 by Cygnus Solutions. The simulator supports the instruction sets
6067 of most MIPS variants.
6071 Sparc configurations may now include the ERC32 simulator contributed
6072 by the European Space Agency. The simulator is not built into
6073 Sparc targets by default; configure with --enable-sim to include it.
6077 For target configurations that may include multiple variants of a
6078 basic architecture (such as MIPS and SH), you may now set the
6079 architecture explicitly. "set arch" sets, "info arch" lists
6080 the possible architectures.
6082 *** Changes in GDB-4.16:
6084 * New native configurations
6086 Windows 95, x86 Windows NT i[345]86-*-cygwin32
6087 M68K NetBSD m68k-*-netbsd*
6088 PowerPC AIX 4.x powerpc-*-aix*
6089 PowerPC MacOS powerpc-*-macos*
6090 PowerPC Windows NT powerpcle-*-cygwin32
6091 RS/6000 AIX 4.x rs6000-*-aix4*
6095 ARM with RDP protocol arm-*-*
6096 I960 with MON960 i960-*-coff
6097 MIPS VxWorks mips*-*-vxworks*
6098 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6099 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6101 Matra Sparclet sparclet-*-*
6105 The powerpc-eabi configuration now includes the PSIM simulator,
6106 contributed by Andrew Cagney, with assistance from Mike Meissner.
6107 PSIM is a very elaborate model of the PowerPC, including not only
6108 basic instruction set execution, but also details of execution unit
6109 performance and I/O hardware. See sim/ppc/README for more details.
6113 GDB now works with Solaris 2.5.
6115 * Windows 95/NT native
6117 GDB will now work as a native debugger on Windows 95 and Windows NT.
6118 To build it from source, you must use the "gnu-win32" environment,
6119 which uses a DLL to emulate enough of Unix to run the GNU tools.
6120 Further information, binaries, and sources are available at
6121 ftp.cygnus.com, under pub/gnu-win32.
6123 * dont-repeat command
6125 If a user-defined command includes the command `dont-repeat', then the
6126 command will not be repeated if the user just types return. This is
6127 useful if the command is time-consuming to run, so that accidental
6128 extra keystrokes don't run the same command many times.
6130 * Send break instead of ^C
6132 The standard remote protocol now includes an option to send a break
6133 rather than a ^C to the target in order to interrupt it. By default,
6134 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6136 * Remote protocol timeout
6138 The standard remote protocol includes a new variable `remotetimeout'
6139 that allows you to set the number of seconds before GDB gives up trying
6140 to read from the target. The default value is 2.
6142 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6144 By default GDB will automatically keep track of objects as they are
6145 loaded and unloaded by the dynamic linker. By using the command `set
6146 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6147 when shared library events occur, thus allowing you to set breakpoints
6148 in shared libraries which are explicitly loaded by the inferior.
6150 Note this feature does not work on hpux8. On hpux9 you must link
6151 /usr/lib/end.o into your program. This feature should work
6152 automatically on hpux10.
6154 * Irix 5.x hardware watchpoint support
6156 Irix 5 configurations now support the use of hardware watchpoints.
6158 * Mips protocol "SYN garbage limit"
6160 When debugging a Mips target using the `target mips' protocol, you
6161 may set the number of characters that GDB will ignore by setting
6162 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6163 every character. The default value is 1050.
6165 * Recording and replaying remote debug sessions
6167 If you set `remotelogfile' to the name of a file, gdb will write to it
6168 a recording of a remote debug session. This recording may then be
6169 replayed back to gdb using "gdbreplay". See gdbserver/README for
6170 details. This is useful when you have a problem with GDB while doing
6171 remote debugging; you can make a recording of the session and send it
6172 to someone else, who can then recreate the problem.
6174 * Speedups for remote debugging
6176 GDB includes speedups for downloading and stepping MIPS systems using
6177 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6178 and more efficient S-record downloading.
6180 * Memory use reductions and statistics collection
6182 GDB now uses less memory and reports statistics about memory usage.
6183 Try the `maint print statistics' command, for example.
6185 *** Changes in GDB-4.15:
6187 * Psymtabs for XCOFF
6189 The symbol reader for AIX GDB now uses partial symbol tables. This
6190 can greatly improve startup time, especially for large executables.
6192 * Remote targets use caching
6194 Remote targets now use a data cache to speed up communication with the
6195 remote side. The data cache could lead to incorrect results because
6196 it doesn't know about volatile variables, thus making it impossible to
6197 debug targets which use memory mapped I/O devices. `set remotecache
6198 off' turns the the data cache off.
6200 * Remote targets may have threads
6202 The standard remote protocol now includes support for multiple threads
6203 in the target system, using new protocol commands 'H' and 'T'. See
6204 gdb/remote.c for details.
6208 If GDB is configured with `--enable-netrom', then it will include
6209 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6210 acts as though it is a bank of ROM on the target board, but you can
6211 write into it over the network. GDB's support consists only of
6212 support for fast loading into the emulated ROM; to debug, you must use
6213 another protocol, such as standard remote protocol. The usual
6214 sequence is something like
6216 target nrom <netrom-hostname>
6218 target remote <netrom-hostname>:1235
6222 GDB now includes support for the Apple Macintosh, as a host only. It
6223 may be run as either an MPW tool or as a standalone application, and
6224 it can debug through the serial port. All the usual GDB commands are
6225 available, but to the target command, you must supply "serial" as the
6226 device type instead of "/dev/ttyXX". See mpw-README in the main
6227 directory for more information on how to build. The MPW configuration
6228 scripts */mpw-config.in support only a few targets, and only the
6229 mips-idt-ecoff target has been tested.
6233 GDB configuration now uses autoconf. This is not user-visible,
6234 but does simplify configuration and building.
6238 GDB now supports hpux10.
6240 *** Changes in GDB-4.14:
6242 * New native configurations
6244 x86 FreeBSD i[345]86-*-freebsd
6245 x86 NetBSD i[345]86-*-netbsd
6246 NS32k NetBSD ns32k-*-netbsd
6247 Sparc NetBSD sparc-*-netbsd
6251 A29K VxWorks a29k-*-vxworks
6252 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6253 CPU32 EST-300 emulator m68*-*-est*
6254 PowerPC ELF powerpc-*-elf
6257 * Alpha OSF/1 support for procfs
6259 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6260 possible to attach to running processes. As the mounting of the /proc
6261 filesystem is optional on the Alpha, GDB automatically determines
6262 the availability of /proc during startup. This can lead to problems
6263 if /proc is unmounted after GDB has been started.
6265 * Arguments to user-defined commands
6267 User commands may accept up to 10 arguments separated by whitespace.
6268 Arguments are accessed within the user command via $arg0..$arg9. A
6271 print $arg0 + $arg1 + $arg2
6273 To execute the command use:
6276 Defines the command "adder" which prints the sum of its three arguments.
6277 Note the arguments are text substitutions, so they may reference variables,
6278 use complex expressions, or even perform inferior function calls.
6280 * New `if' and `while' commands
6282 This makes it possible to write more sophisticated user-defined
6283 commands. Both commands take a single argument, which is the
6284 expression to evaluate, and must be followed by the commands to
6285 execute, one per line, if the expression is nonzero, the list being
6286 terminated by the word `end'. The `if' command list may include an
6287 `else' word, which causes the following commands to be executed only
6288 if the expression is zero.
6290 * Fortran source language mode
6292 GDB now includes partial support for Fortran 77. It will recognize
6293 Fortran programs and can evaluate a subset of Fortran expressions, but
6294 variables and functions may not be handled correctly. GDB will work
6295 with G77, but does not yet know much about symbols emitted by other
6298 * Better HPUX support
6300 Most debugging facilities now work on dynamic executables for HPPAs
6301 running hpux9 or later. You can attach to running dynamically linked
6302 processes, but by default the dynamic libraries will be read-only, so
6303 for instance you won't be able to put breakpoints in them. To change
6304 that behavior do the following before running the program:
6310 This will cause the libraries to be mapped private and read-write.
6311 To revert to the normal behavior, do this:
6317 You cannot set breakpoints or examine data in the library until after
6318 the library is loaded if the function/data symbols do not have
6321 GDB can now also read debug symbols produced by the HP C compiler on
6322 HPPAs (sorry, no C++, Fortran or 68k support).
6324 * Target byte order now dynamically selectable
6326 You can choose which byte order to use with a target system, via the
6327 commands "set endian big" and "set endian little", and you can see the
6328 current setting by using "show endian". You can also give the command
6329 "set endian auto", in which case GDB will use the byte order
6330 associated with the executable. Currently, only embedded MIPS
6331 configurations support dynamic selection of target byte order.
6333 * New DOS host serial code
6335 This version uses DPMI interrupts to handle buffered I/O, so you
6336 no longer need to run asynctsr when debugging boards connected to
6339 *** Changes in GDB-4.13:
6341 * New "complete" command
6343 This lists all the possible completions for the rest of the line, if it
6344 were to be given as a command itself. This is intended for use by emacs.
6346 * Trailing space optional in prompt
6348 "set prompt" no longer adds a space for you after the prompt you set. This
6349 allows you to set a prompt which ends in a space or one that does not.
6351 * Breakpoint hit counts
6353 "info break" now displays a count of the number of times the breakpoint
6354 has been hit. This is especially useful in conjunction with "ignore"; you
6355 can ignore a large number of breakpoint hits, look at the breakpoint info
6356 to see how many times the breakpoint was hit, then run again, ignoring one
6357 less than that number, and this will get you quickly to the last hit of
6360 * Ability to stop printing at NULL character
6362 "set print null-stop" will cause GDB to stop printing the characters of
6363 an array when the first NULL is encountered. This is useful when large
6364 arrays actually contain only short strings.
6366 * Shared library breakpoints
6368 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6369 breakpoints in shared libraries before the executable is run.
6371 * Hardware watchpoints
6373 There is a new hardware breakpoint for the watch command for sparclite
6374 targets. See gdb/sparclite/hw_breakpoint.note.
6376 Hardware watchpoints are also now supported under GNU/Linux.
6380 Annotations have been added. These are for use with graphical interfaces,
6381 and are still experimental. Currently only gdba.el uses these.
6383 * Improved Irix 5 support
6385 GDB now works properly with Irix 5.2.
6387 * Improved HPPA support
6389 GDB now works properly with the latest GCC and GAS.
6391 * New native configurations
6393 Sequent PTX4 i[34]86-sequent-ptx4
6394 HPPA running OSF/1 hppa*-*-osf*
6395 Atari TT running SVR4 m68*-*-sysv4*
6396 RS/6000 LynxOS rs6000-*-lynxos*
6400 OS/9000 i[34]86-*-os9k
6401 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6404 * Hitachi SH7000 and E7000-PC ICE support
6406 There is now support for communicating with the Hitachi E7000-PC ICE.
6407 This is available automatically when GDB is configured for the SH.
6411 As usual, a variety of small fixes and improvements, both generic
6412 and configuration-specific. See the ChangeLog for more detail.
6414 *** Changes in GDB-4.12:
6416 * Irix 5 is now supported
6420 GDB-4.12 on the HPPA has a number of changes which make it unable
6421 to debug the output from the currently released versions of GCC and
6422 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6423 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6424 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6427 *** Changes in GDB-4.11:
6429 * User visible changes:
6433 The "set remotedebug" option is now consistent between the mips remote
6434 target, remote targets using the gdb-specific protocol, UDI (AMD's
6435 debug protocol for the 29k) and the 88k bug monitor. It is now an
6436 integer specifying a debug level (normally 0 or 1, but 2 means more
6437 debugging info for the mips target).
6439 * DEC Alpha native support
6441 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6442 debug info, but GDB works fairly well with the DEC compiler and should
6443 work with a future GCC release. See the README file for a few
6444 Alpha-specific notes.
6446 * Preliminary thread implementation
6448 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6450 * LynxOS native and target support for 386
6452 This release has been hosted on LynxOS 2.2, and also can be configured
6453 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6456 * Improvements in C++ mangling/demangling.
6458 This release has much better g++ debugging, specifically in name
6459 mangling/demangling, virtual function calls, print virtual table,
6460 call methods, ...etc.
6462 *** Changes in GDB-4.10:
6464 * User visible changes:
6466 Remote debugging using the GDB-specific (`target remote') protocol now
6467 supports the `load' command. This is only useful if you have some
6468 other way of getting the stub to the target system, and you can put it
6469 somewhere in memory where it won't get clobbered by the download.
6471 Filename completion now works.
6473 When run under emacs mode, the "info line" command now causes the
6474 arrow to point to the line specified. Also, "info line" prints
6475 addresses in symbolic form (as well as hex).
6477 All vxworks based targets now support a user settable option, called
6478 vxworks-timeout. This option represents the number of seconds gdb
6479 should wait for responses to rpc's. You might want to use this if
6480 your vxworks target is, perhaps, a slow software simulator or happens
6481 to be on the far side of a thin network line.
6485 This release contains support for using a DEC alpha as a GDB host for
6486 cross debugging. Native alpha debugging is not supported yet.
6489 *** Changes in GDB-4.9:
6493 This is the first GDB release which is accompanied by a matching testsuite.
6494 The testsuite requires installation of dejagnu, which should be available
6495 via ftp from most sites that carry GNU software.
6499 'Cfront' style demangling has had its name changed to 'ARM' style, to
6500 emphasize that it was written from the specifications in the C++ Annotated
6501 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6502 disclaimers, it still generated too much confusion with users attempting to
6503 use gdb with AT&T cfront.
6507 GDB now uses a standard remote interface to a simulator library.
6508 So far, the library contains simulators for the Zilog Z8001/2, the
6509 Hitachi H8/300, H8/500 and Super-H.
6511 * New targets supported
6513 H8/300 simulator h8300-hitachi-hms or h8300hms
6514 H8/500 simulator h8500-hitachi-hms or h8500hms
6515 SH simulator sh-hitachi-hms or sh
6516 Z8000 simulator z8k-zilog-none or z8ksim
6517 IDT MIPS board over serial line mips-idt-ecoff
6519 Cross-debugging to GO32 targets is supported. It requires a custom
6520 version of the i386-stub.c module which is integrated with the
6521 GO32 memory extender.
6523 * New remote protocols
6525 MIPS remote debugging protocol.
6527 * New source languages supported
6529 This version includes preliminary support for Chill, a Pascal like language
6530 used by telecommunications companies. Chill support is also being integrated
6531 into the GNU compiler, but we don't know when it will be publically available.
6534 *** Changes in GDB-4.8:
6536 * HP Precision Architecture supported
6538 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6539 version of this support was available as a set of patches from the
6540 University of Utah. GDB does not support debugging of programs
6541 compiled with the HP compiler, because HP will not document their file
6542 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6543 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6545 Many problems in the preliminary version have been fixed.
6547 * Faster and better demangling
6549 We have improved template demangling and fixed numerous bugs in the GNU style
6550 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6551 character types (wchar_t) are now supported. Demangling of each symbol is now
6552 only done once, and is cached when the symbol table for a file is read in.
6553 This results in a small increase in memory usage for C programs, a moderate
6554 increase in memory usage for C++ programs, and a fantastic speedup in
6557 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6558 from the specifications in the Annotated Reference Manual, which AT&T's
6559 compiler does not actually implement.
6561 * G++ multiple inheritance compiler problem
6563 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6564 inheritance lattices was reworked to properly discover ambiguities. We
6565 recently found an example which causes this new algorithm to fail in a
6566 very subtle way, producing bad debug information for those classes.
6567 The file 'gcc.patch' (in this directory) can be applied to gcc to
6568 circumvent the problem. A future GCC release will contain a complete
6571 The previous G++ debug info problem (mentioned below for the gdb-4.7
6572 release) is fixed in gcc version 2.3.2.
6574 * Improved configure script
6576 The `configure' script will now attempt to guess your system type if
6577 you don't supply a host system type. The old scheme of supplying a
6578 host system triplet is preferable over using this. All the magic is
6579 done in the new `config.guess' script. Examine it for details.
6581 We have also brought our configure script much more in line with the FSF's
6582 version. It now supports the --with-xxx options. In particular,
6583 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6584 The resulting GDB will not be able to read arbitrary object file formats --
6585 only the format ``expected'' to be used on the configured target system.
6586 We hope to make this the default in a future release.
6588 * Documentation improvements
6590 There's new internal documentation on how to modify GDB, and how to
6591 produce clean changes to the code. We implore people to read it
6592 before submitting changes.
6594 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6595 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6596 `info' files are also provided. To build `info' files from scratch,
6597 you will need the latest `makeinfo' release, which will be available in
6598 a future texinfo-X.Y release.
6600 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6601 We're not sure exactly which versions have this problem, but it has
6602 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6603 or better. If that isn't possible, there is a patch in
6604 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6605 around this problem.
6609 GDB now supports array constants that can be used in expressions typed in by
6610 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6611 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6614 The new directory `gdb/sparclite' contains a program that demonstrates
6615 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6617 * New native hosts supported
6619 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6620 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6622 * New targets supported
6624 AMD 29k family via UDI a29k-amd-udi or udi29k
6626 * New file formats supported
6628 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6629 HPUX core files, and SCO 3.2v2 core files.
6633 Attaching to processes now works again; thanks for the many bug reports.
6635 We have also stomped on a bunch of core dumps caused by
6636 printf_filtered("%s") problems.
6638 We eliminated a copyright problem on the rpc and ptrace header files
6639 for VxWorks, which was discovered at the last minute during the 4.7
6640 release. You should now be able to build a VxWorks GDB.
6642 You can now interrupt gdb while an attached process is running. This
6643 will cause the attached process to stop, and give control back to GDB.
6645 We fixed problems caused by using too many file descriptors
6646 for reading symbols from object files and libraries. This was
6647 especially a problem for programs that used many (~100) shared
6650 The `step' command now only enters a subroutine if there is line number
6651 information for the subroutine. Otherwise it acts like the `next'
6652 command. Previously, `step' would enter subroutines if there was
6653 any debugging information about the routine. This avoids problems
6654 when using `cc -g1' on MIPS machines.
6656 * Internal improvements
6658 GDB's internal interfaces have been improved to make it easier to support
6659 debugging of multiple languages in the future.
6661 GDB now uses a common structure for symbol information internally.
6662 Minimal symbols (derived from linkage symbols in object files), partial
6663 symbols (from a quick scan of debug information), and full symbols
6664 contain a common subset of information, making it easier to write
6665 shared code that handles any of them.
6667 * New command line options
6669 We now accept --silent as an alias for --quiet.
6673 The memory-mapped-malloc library is now licensed under the GNU Library
6674 General Public License.
6676 *** Changes in GDB-4.7:
6678 * Host/native/target split
6680 GDB has had some major internal surgery to untangle the support for
6681 hosts and remote targets. Now, when you configure GDB for a remote
6682 target, it will no longer load in all of the support for debugging
6683 local programs on the host. When fully completed and tested, this will
6684 ensure that arbitrary host/target combinations are possible.
6686 The primary conceptual shift is to separate the non-portable code in
6687 GDB into three categories. Host specific code is required any time GDB
6688 is compiled on that host, regardless of the target. Target specific
6689 code relates to the peculiarities of the target, but can be compiled on
6690 any host. Native specific code is everything else: it can only be
6691 built when the host and target are the same system. Child process
6692 handling and core file support are two common `native' examples.
6694 GDB's use of /proc for controlling Unix child processes is now cleaner.
6695 It has been split out into a single module under the `target_ops' vector,
6696 plus two native-dependent functions for each system that uses /proc.
6698 * New hosts supported
6700 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6701 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6702 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6704 * New targets supported
6706 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6707 68030 and CPU32 m68030-*-*, m68332-*-*
6709 * New native hosts supported
6711 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6712 (386bsd is not well tested yet)
6713 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6715 * New file formats supported
6717 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6718 supports reading of `a.out.adobe' object files, which are an a.out
6719 format extended with minimal information about multiple sections.
6723 `show copying' is the same as the old `info copying'.
6724 `show warranty' is the same as `info warrantee'.
6725 These were renamed for consistency. The old commands continue to work.
6727 `info handle' is a new alias for `info signals'.
6729 You can now define pre-command hooks, which attach arbitrary command
6730 scripts to any command. The commands in the hook will be executed
6731 prior to the user's command. You can also create a hook which will be
6732 executed whenever the program stops. See gdb.texinfo.
6736 We now deal with Cfront style name mangling, and can even extract type
6737 info from mangled symbols. GDB can automatically figure out which
6738 symbol mangling style your C++ compiler uses.
6740 Calling of methods and virtual functions has been improved as well.
6744 The crash that occured when debugging Sun Ansi-C compiled binaries is
6745 fixed. This was due to mishandling of the extra N_SO stabs output
6748 We also finally got Ultrix 4.2 running in house, and fixed core file
6749 support, with help from a dozen people on the net.
6751 John M. Farrell discovered that the reason that single-stepping was so
6752 slow on all of the Mips based platforms (primarily SGI and DEC) was
6753 that we were trying to demangle and lookup a symbol used for internal
6754 purposes on every instruction that was being stepped through. Changing
6755 the name of that symbol so that it couldn't be mistaken for a C++
6756 mangled symbol sped things up a great deal.
6758 Rich Pixley sped up symbol lookups in general by getting much smarter
6759 about when C++ symbol mangling is necessary. This should make symbol
6760 completion (TAB on the command line) much faster. It's not as fast as
6761 we'd like, but it's significantly faster than gdb-4.6.
6765 A new user controllable variable 'call_scratch_address' can
6766 specify the location of a scratch area to be used when GDB
6767 calls a function in the target. This is necessary because the
6768 usual method of putting the scratch area on the stack does not work
6769 in systems that have separate instruction and data spaces.
6771 We integrated changes to support the 29k UDI (Universal Debugger
6772 Interface), but discovered at the last minute that we didn't have all
6773 of the appropriate copyright paperwork. We are working with AMD to
6774 resolve this, and hope to have it available soon.
6778 We have sped up the remote serial line protocol, especially for targets
6779 with lots of registers. It now supports a new `expedited status' ('T')
6780 message which can be used in place of the existing 'S' status message.
6781 This allows the remote stub to send only the registers that GDB
6782 needs to make a quick decision about single-stepping or conditional
6783 breakpoints, eliminating the need to fetch the entire register set for
6784 each instruction being stepped through.
6786 The GDB remote serial protocol now implements a write-through cache for
6787 registers, only re-reading the registers if the target has run.
6789 There is also a new remote serial stub for SPARC processors. You can
6790 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6791 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6792 processor with a serial port.
6796 Configure.in files have become much easier to read and modify. A new
6797 `table driven' format makes it more obvious what configurations are
6798 supported, and what files each one uses.
6802 There is a new opcodes library which will eventually contain all of the
6803 disassembly routines and opcode tables. At present, it only contains
6804 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6805 disassembler (binutils/objdump) to share these routines.
6807 The libiberty library is now copylefted under the GNU Library General
6808 Public License. This allows more liberal use, and was done so libg++
6809 can use it. This makes no difference to GDB, since the Library License
6810 grants all the rights from the General Public License.
6814 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6815 reference to the stabs symbol info used by the debugger. It is (as far
6816 as we know) the only published document on this fascinating topic. We
6817 encourage you to read it, compare it to the stabs information on your
6818 system, and send improvements on the document in general (to
6819 bug-gdb@prep.ai.mit.edu).
6821 And, of course, many bugs have been fixed.
6824 *** Changes in GDB-4.6:
6826 * Better support for C++ function names
6828 GDB now accepts as input the "demangled form" of C++ overloaded function
6829 names and member function names, and can do command completion on such names
6830 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6831 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6832 Make use of command completion, it is your friend.
6834 GDB also now accepts a variety of C++ mangled symbol formats. They are
6835 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6836 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6837 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6838 for the list of formats.
6840 * G++ symbol mangling problem
6842 Recent versions of gcc have a bug in how they emit debugging information for
6843 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6844 directory) can be applied to gcc to fix the problem. Alternatively, if you
6845 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6846 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6847 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6850 * New 'maintenance' command
6852 All of the commands related to hacking GDB internals have been moved out of
6853 the main command set, and now live behind the 'maintenance' command. This
6854 can also be abbreviated as 'mt'. The following changes were made:
6856 dump-me -> maintenance dump-me
6857 info all-breakpoints -> maintenance info breakpoints
6858 printmsyms -> maintenance print msyms
6859 printobjfiles -> maintenance print objfiles
6860 printpsyms -> maintenance print psymbols
6861 printsyms -> maintenance print symbols
6863 The following commands are new:
6865 maintenance demangle Call internal GDB demangler routine to
6866 demangle a C++ link name and prints the result.
6867 maintenance print type Print a type chain for a given symbol
6869 * Change to .gdbinit file processing
6871 We now read the $HOME/.gdbinit file before processing the argv arguments
6872 (e.g. reading symbol files or core files). This allows global parameters to
6873 be set, which will apply during the symbol reading. The ./.gdbinit is still
6874 read after argv processing.
6876 * New hosts supported
6878 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6880 GNU/Linux support i386-unknown-linux or linux
6882 We are also including code to support the HP/PA running BSD and HPUX. This
6883 is almost guaranteed not to work, as we didn't have time to test or build it
6884 for this release. We are including it so that the more adventurous (or
6885 masochistic) of you can play with it. We also had major problems with the
6886 fact that the compiler that we got from HP doesn't support the -g option.
6889 * New targets supported
6891 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6893 * More smarts about finding #include files
6895 GDB now remembers the compilation directory for all include files, and for
6896 all files from which C is generated (like yacc and lex sources). This
6897 greatly improves GDB's ability to find yacc/lex sources, and include files,
6898 especially if you are debugging your program from a directory different from
6899 the one that contains your sources.
6901 We also fixed a bug which caused difficulty with listing and setting
6902 breakpoints in include files which contain C code. (In the past, you had to
6903 try twice in order to list an include file that you hadn't looked at before.)
6905 * Interesting infernals change
6907 GDB now deals with arbitrary numbers of sections, where the symbols for each
6908 section must be relocated relative to that section's landing place in the
6909 target's address space. This work was needed to support ELF with embedded
6910 stabs used by Solaris-2.0.
6912 * Bug fixes (of course!)
6914 There have been loads of fixes for the following things:
6915 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6916 i960, stabs, DOS(GO32), procfs, etc...
6918 See the ChangeLog for details.
6920 *** Changes in GDB-4.5:
6922 * New machines supported (host and target)
6924 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6926 SGI Irix-4.x mips-sgi-irix4 or iris4
6928 * New malloc package
6930 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6931 Mmalloc is capable of handling mutiple heaps of memory. It is also
6932 capable of saving a heap to a file, and then mapping it back in later.
6933 This can be used to greatly speedup the startup of GDB by using a
6934 pre-parsed symbol table which lives in a mmalloc managed heap. For
6935 more details, please read mmalloc/mmalloc.texi.
6939 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6940 'help info proc' for details.
6942 * MIPS ecoff symbol table format
6944 The code that reads MIPS symbol table format is now supported on all hosts.
6945 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6948 * File name changes for MS-DOS
6950 Many files in the config directories have been renamed to make it easier to
6951 support GDB on MS-DOSe systems (which have very restrictive file name
6952 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6953 environment) is close to working but has some remaining problems. Note
6954 that debugging of DOS programs is not supported, due to limitations
6955 in the ``operating system'', but it can be used to host cross-debugging.
6957 * Cross byte order fixes
6959 Many fixes have been made to support cross debugging of Sparc and MIPS
6960 targets from hosts whose byte order differs.
6962 * New -mapped and -readnow options
6964 If memory-mapped files are available on your system through the 'mmap'
6965 system call, you can use the -mapped option on the `file' or
6966 `symbol-file' commands to cause GDB to write the symbols from your
6967 program into a reusable file. If the program you are debugging is
6968 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6969 Future GDB debugging sessions will notice the presence of this file,
6970 and will quickly map in symbol information from it, rather than reading
6971 the symbol table from the executable program. Using the '-mapped'
6972 option in a GDB `file' or `symbol-file' command has the same effect as
6973 starting GDB with the '-mapped' command-line option.
6975 You can cause GDB to read the entire symbol table immediately by using
6976 the '-readnow' option with any of the commands that load symbol table
6977 information (or on the GDB command line). This makes the command
6978 slower, but makes future operations faster.
6980 The -mapped and -readnow options are typically combined in order to
6981 build a `fred.syms' file that contains complete symbol information.
6982 A simple GDB invocation to do nothing but build a `.syms' file for future
6985 gdb -batch -nx -mapped -readnow programname
6987 The `.syms' file is specific to the host machine on which GDB is run.
6988 It holds an exact image of GDB's internal symbol table. It cannot be
6989 shared across multiple host platforms.
6991 * longjmp() handling
6993 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6994 siglongjmp() without losing control. This feature has not yet been ported to
6995 all systems. It currently works on many 386 platforms, all MIPS-based
6996 platforms (SGI, DECstation, etc), and Sun3/4.
7000 Preliminary work has been put in to support the new Solaris OS from Sun. At
7001 this time, it can control and debug processes, but it is not capable of
7006 As always, many many bug fixes. The major areas were with g++, and mipsread.
7007 People using the MIPS-based platforms should experience fewer mysterious
7008 crashes and trashed symbol tables.
7010 *** Changes in GDB-4.4:
7012 * New machines supported (host and target)
7014 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7016 BSD Reno on Vax vax-dec-bsd
7017 Ultrix on Vax vax-dec-ultrix
7019 * New machines supported (target)
7021 AMD 29000 embedded, using EBMON a29k-none-none
7025 GDB continues to improve its handling of C++. `References' work better.
7026 The demangler has also been improved, and now deals with symbols mangled as
7027 per the Annotated C++ Reference Guide.
7029 GDB also now handles `stabs' symbol information embedded in MIPS
7030 `ecoff' symbol tables. Since the ecoff format was not easily
7031 extensible to handle new languages such as C++, this appeared to be a
7032 good way to put C++ debugging info into MIPS binaries. This option
7033 will be supported in the GNU C compiler, version 2, when it is
7036 * New features for SVR4
7038 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
7039 shared libraries. Debugging dynamically linked programs should present
7040 only minor differences from debugging statically linked programs.
7042 The `info proc' command will print out information about any process
7043 on an SVR4 system (including the one you are debugging). At the moment,
7044 it prints the address mappings of the process.
7046 If you bring up GDB on another SVR4 system, please send mail to
7047 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
7049 * Better dynamic linking support in SunOS
7051 Reading symbols from shared libraries which contain debugging symbols
7052 now works properly. However, there remain issues such as automatic
7053 skipping of `transfer vector' code during function calls, which
7054 make it harder to debug code in a shared library, than to debug the
7055 same code linked statically.
7059 GDB is now using the latest `getopt' routines from the FSF. This
7060 version accepts the -- prefix for options with long names. GDB will
7061 continue to accept the old forms (-option and +option) as well.
7062 Various single letter abbreviations for options have been explicity
7063 added to the option table so that they won't get overshadowed in the
7064 future by other options that begin with the same letter.
7068 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
7069 Many assorted bugs have been handled. Many more remain to be handled.
7070 See the various ChangeLog files (primarily in gdb and bfd) for details.
7073 *** Changes in GDB-4.3:
7075 * New machines supported (host and target)
7077 Amiga 3000 running Amix m68k-cbm-svr4 or amix
7078 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
7079 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
7081 * Almost SCO Unix support
7083 We had hoped to support:
7084 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
7085 (except for core file support), but we discovered very late in the release
7086 that it has problems with process groups that render gdb unusable. Sorry
7087 about that. I encourage people to fix it and post the fixes.
7089 * Preliminary ELF and DWARF support
7091 GDB can read ELF object files on System V Release 4, and can handle
7092 debugging records for C, in DWARF format, in ELF files. This support
7093 is preliminary. If you bring up GDB on another SVR4 system, please
7094 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7099 GDB now uses the latest `readline' library. One user-visible change
7100 is that two tabs will list possible command completions, which previously
7101 required typing M-? (meta-question mark, or ESC ?).
7105 The `stepi' bug that many of you noticed has been squashed.
7106 Many bugs in C++ have been handled. Many more remain to be handled.
7107 See the various ChangeLog files (primarily in gdb and bfd) for details.
7109 * State of the MIPS world (in case you wondered):
7111 GDB can understand the symbol tables emitted by the compilers
7112 supplied by most vendors of MIPS-based machines, including DEC. These
7113 symbol tables are in a format that essentially nobody else uses.
7115 Some versions of gcc come with an assembler post-processor called
7116 mips-tfile. This program is required if you want to do source-level
7117 debugging of gcc-compiled programs. I believe FSF does not ship
7118 mips-tfile with gcc version 1, but it will eventually come with gcc
7121 Debugging of g++ output remains a problem. g++ version 1.xx does not
7122 really support it at all. (If you're lucky, you should be able to get
7123 line numbers and stack traces to work, but no parameters or local
7124 variables.) With some work it should be possible to improve the
7127 When gcc version 2 is released, you will have somewhat better luck.
7128 However, even then you will get confusing results for inheritance and
7131 We will eventually provide full debugging of g++ output on
7132 DECstations. This will probably involve some kind of stabs-in-ecoff
7133 encapulation, but the details have not been worked out yet.
7136 *** Changes in GDB-4.2:
7138 * Improved configuration
7140 Only one copy of `configure' exists now, and it is not self-modifying.
7141 Porting BFD is simpler.
7145 The `step' and `next' commands now only stop at the first instruction
7146 of a source line. This prevents the multiple stops that used to occur
7147 in switch statements, for-loops, etc. `Step' continues to stop if a
7148 function that has debugging information is called within the line.
7152 Lots of small bugs fixed. More remain.
7154 * New host supported (not target)
7156 Intel 386 PC clone running Mach i386-none-mach
7159 *** Changes in GDB-4.1:
7161 * Multiple source language support
7163 GDB now has internal scaffolding to handle several source languages.
7164 It determines the type of each source file from its filename extension,
7165 and will switch expression parsing and number formatting to match the
7166 language of the function in the currently selected stack frame.
7167 You can also specifically set the language to be used, with
7168 `set language c' or `set language modula-2'.
7172 GDB now has preliminary support for the GNU Modula-2 compiler,
7173 currently under development at the State University of New York at
7174 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7175 continue through the fall of 1991 and into 1992.
7177 Other Modula-2 compilers are currently not supported, and attempting to
7178 debug programs compiled with them will likely result in an error as the
7179 symbol table is read. Feel free to work on it, though!
7181 There are hooks in GDB for strict type checking and range checking,
7182 in the `Modula-2 philosophy', but they do not currently work.
7186 GDB can now write to executable and core files (e.g. patch
7187 a variable's value). You must turn this switch on, specify
7188 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7189 by assigning a new value to a variable. Modifications take
7192 * Automatic SunOS shared library reading
7194 When you run your program, GDB automatically determines where its
7195 shared libraries (if any) have been loaded, and reads their symbols.
7196 The `share' command is no longer needed. This also works when
7197 examining core files.
7201 You can specify the number of lines that the `list' command shows.
7204 * New machines supported (host and target)
7206 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7207 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7208 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7210 * New hosts supported (not targets)
7212 IBM RT/PC: romp-ibm-aix or rtpc
7214 * New targets supported (not hosts)
7216 AMD 29000 embedded with COFF a29k-none-coff
7217 AMD 29000 embedded with a.out a29k-none-aout
7218 Ultracomputer remote kernel debug a29k-nyu-kern
7220 * New remote interfaces
7226 *** Changes in GDB-4.0:
7230 Wide output is wrapped at good places to make the output more readable.
7232 Gdb now supports cross-debugging from a host machine of one type to a
7233 target machine of another type. Communication with the target system
7234 is over serial lines. The ``target'' command handles connecting to the
7235 remote system; the ``load'' command will download a program into the
7236 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7237 also supports debugging of realtime processes running under VxWorks,
7238 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7239 stub on the target system.
7241 New CPUs supported include the AMD 29000 and Intel 960.
7243 GDB now reads object files and symbol tables via a ``binary file''
7244 library, which allows a single copy of GDB to debug programs of multiple
7245 object file types such as a.out and coff.
7247 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7248 refcard.dvi and refcard.ps are available to format it).
7251 * Control-Variable user interface simplified
7253 All variables that control the operation of the debugger can be set
7254 by the ``set'' command, and displayed by the ``show'' command.
7256 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7257 ``Show prompt'' produces the response:
7258 Gdb's prompt is new-gdb=>.
7260 What follows are the NEW set commands. The command ``help set'' will
7261 print a complete list of old and new set commands. ``help set FOO''
7262 will give a longer description of the variable FOO. ``show'' will show
7263 all of the variable descriptions and their current settings.
7265 confirm on/off: Enables warning questions for operations that are
7266 hard to recover from, e.g. rerunning the program while
7267 it is already running. Default is ON.
7269 editing on/off: Enables EMACS style command line editing
7270 of input. Previous lines can be recalled with
7271 control-P, the current line can be edited with control-B,
7272 you can search for commands with control-R, etc.
7275 history filename NAME: NAME is where the gdb command history
7276 will be stored. The default is .gdb_history,
7277 or the value of the environment variable
7280 history size N: The size, in commands, of the command history. The
7281 default is 256, or the value of the environment variable
7284 history save on/off: If this value is set to ON, the history file will
7285 be saved after exiting gdb. If set to OFF, the
7286 file will not be saved. The default is OFF.
7288 history expansion on/off: If this value is set to ON, then csh-like
7289 history expansion will be performed on
7290 command line input. The default is OFF.
7292 radix N: Sets the default radix for input and output. It can be set
7293 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7294 in the current radix, so "set radix 10" is always a no-op.
7296 height N: This integer value is the number of lines on a page. Default
7297 is 24, the current `stty rows'' setting, or the ``li#''
7298 setting from the termcap entry matching the environment
7301 width N: This integer value is the number of characters on a line.
7302 Default is 80, the current `stty cols'' setting, or the ``co#''
7303 setting from the termcap entry matching the environment
7306 Note: ``set screensize'' is obsolete. Use ``set height'' and
7307 ``set width'' instead.
7309 print address on/off: Print memory addresses in various command displays,
7310 such as stack traces and structure values. Gdb looks
7311 more ``symbolic'' if you turn this off; it looks more
7312 ``machine level'' with it on. Default is ON.
7314 print array on/off: Prettyprint arrays. New convenient format! Default
7317 print demangle on/off: Print C++ symbols in "source" form if on,
7320 print asm-demangle on/off: Same, for assembler level printouts
7323 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7326 * Support for Epoch Environment.
7328 The epoch environment is a version of Emacs v18 with windowing. One
7329 new command, ``inspect'', is identical to ``print'', except that if you
7330 are running in the epoch environment, the value is printed in its own
7334 * Support for Shared Libraries
7336 GDB can now debug programs and core files that use SunOS shared libraries.
7337 Symbols from a shared library cannot be referenced
7338 before the shared library has been linked with the program (this
7339 happens after you type ``run'' and before the function main() is entered).
7340 At any time after this linking (including when examining core files
7341 from dynamically linked programs), gdb reads the symbols from each
7342 shared library when you type the ``sharedlibrary'' command.
7343 It can be abbreviated ``share''.
7345 sharedlibrary REGEXP: Load shared object library symbols for files
7346 matching a unix regular expression. No argument
7347 indicates to load symbols for all shared libraries.
7349 info sharedlibrary: Status of loaded shared libraries.
7354 A watchpoint stops execution of a program whenever the value of an
7355 expression changes. Checking for this slows down execution
7356 tremendously whenever you are in the scope of the expression, but is
7357 quite useful for catching tough ``bit-spreader'' or pointer misuse
7358 problems. Some machines such as the 386 have hardware for doing this
7359 more quickly, and future versions of gdb will use this hardware.
7361 watch EXP: Set a watchpoint (breakpoint) for an expression.
7363 info watchpoints: Information about your watchpoints.
7365 delete N: Deletes watchpoint number N (same as breakpoints).
7366 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7367 enable N: Re-enables watchpoint number N (same as breakpoints).
7370 * C++ multiple inheritance
7372 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7375 * C++ exception handling
7377 Gdb now supports limited C++ exception handling. Besides the existing
7378 ability to breakpoint on an exception handler, gdb can breakpoint on
7379 the raising of an exception (before the stack is peeled back to the
7382 catch FOO: If there is a FOO exception handler in the dynamic scope,
7383 set a breakpoint to catch exceptions which may be raised there.
7384 Multiple exceptions (``catch foo bar baz'') may be caught.
7386 info catch: Lists all exceptions which may be caught in the
7387 current stack frame.
7390 * Minor command changes
7392 The command ``call func (arg, arg, ...)'' now acts like the print
7393 command, except it does not print or save a value if the function's result
7394 is void. This is similar to dbx usage.
7396 The ``up'' and ``down'' commands now always print the frame they end up
7397 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7398 frames without printing.
7400 * New directory command
7402 'dir' now adds directories to the FRONT of the source search path.
7403 The path starts off empty. Source files that contain debug information
7404 about the directory in which they were compiled can be found even
7405 with an empty path; Sun CC and GCC include this information. If GDB can't
7406 find your source file in the current directory, type "dir .".
7408 * Configuring GDB for compilation
7410 For normal use, type ``./configure host''. See README or gdb.texinfo
7413 GDB now handles cross debugging. If you are remotely debugging between
7414 two different machines, type ``./configure host -target=targ''.
7415 Host is the machine where GDB will run; targ is the machine
7416 where the program that you are debugging will run.