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.
21 ** The gdb.Value type has a new method 'format_string' which returns a
22 string representing the value. The formatting is controlled by the
23 optional keyword arguments: 'raw', 'pretty_arrays', 'pretty_structs',
24 'array_indexes', 'symbols', 'unions', 'deref_refs', 'actual_objects',
25 'static_members', 'max_elements', 'repeat_threshold', and 'format'.
28 *** Changes in GDB 8.3
30 * GDB and GDBserver now support access to additional registers on
31 PowerPC GNU/Linux targets: PPR, DSCR, TAR, EBB/PMU registers, and
34 * GDB now has experimental support for the compilation and injection of
35 C++ source code into the inferior. This beta release does not include
36 support for several language features, such as templates, constructors,
39 This feature requires GCC 7.1 or higher built with libcp1.so
42 * GDB and GDBserver now support IPv6 connections. IPv6 addresses
43 can be passed using the '[ADDRESS]:PORT' notation, or the regular
44 'ADDRESS:PORT' method.
46 * DWARF index cache: GDB can now automatically save indices of DWARF
47 symbols on disk to speed up further loading of the same binaries.
49 * Ada task switching is now supported on aarch64-elf targets when
50 debugging a program using the Ravenscar Profile. For more information,
51 see the "Tasking Support when using the Ravenscar Profile" section
52 in the GDB user manual.
54 * GDB in batch mode now exits with status 1 if the last command to be
57 * The RISC-V target now supports target descriptions.
59 * System call catchpoints now support system call aliases on FreeBSD.
60 When the ABI of a system call changes in FreeBSD, this is
61 implemented by leaving a compatibility system call using the old ABI
62 at the existing number and allocating a new system call number for
63 the new ABI. For example, FreeBSD 12 altered the layout of 'struct
64 kevent' used by the 'kevent' system call. As a result, FreeBSD 12
65 kernels ship with both 'kevent' and 'freebsd11_kevent' system calls.
66 The 'freebsd11_kevent' system call is assigned an alias of 'kevent'
67 so that a system call catchpoint for the 'kevent' system call will
68 catch invocations of both the 'kevent' and 'freebsd11_kevent'
69 binaries. This ensures that 'kevent' system calls are caught for
70 binaries using either the old or new ABIs.
72 * Terminal styling is now available for the CLI and the TUI. GNU
73 Source Highlight can additionally be used to provide styling of
74 source code snippets. See the "set style" commands, below, for more
77 * Removed support for old demangling styles arm, edg, gnu, hp and
82 set debug compile-cplus-types
83 show debug compile-cplus-types
84 Control the display of debug output about type conversion in the
85 C++ compile feature. Commands have no effect while compiliong
90 Control whether debug output about files/functions skipping is
93 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
94 Apply a command to some frames.
95 FLAG arguments allow to control what output to produce and how to handle
96 errors raised when applying COMMAND to a frame.
99 Apply a command to all threads (ignoring errors and empty output).
100 Shortcut for 'thread apply all -s COMMAND'.
103 Apply a command to all frames (ignoring errors and empty output).
104 Shortcut for 'frame apply all -s COMMAND'.
107 Apply a command to all frames of all threads (ignoring errors and empty
109 Shortcut for 'thread apply all -s frame apply all -s COMMAND'.
111 maint set dwarf unwinders (on|off)
112 maint show dwarf unwinders
113 Control whether DWARF unwinders can be used.
116 Display a list of open files for a process.
120 Changes to the "frame", "select-frame", and "info frame" CLI commands.
121 These commands all now take a frame specification which
122 is either a frame level, or one of the keywords 'level', 'address',
123 'function', or 'view' followed by a parameter. Selecting a frame by
124 address, or viewing a frame outside the current backtrace now
125 requires the use of a keyword. Selecting a frame by level is
126 unchanged. The MI comment "-stack-select-frame" is unchanged.
128 target remote FILENAME
129 target extended-remote FILENAME
130 If FILENAME is a Unix domain socket, GDB will attempt to connect
131 to this socket instead of opening FILENAME as a character device.
133 info args [-q] [-t TYPEREGEXP] [NAMEREGEXP]
134 info functions [-q] [-t TYPEREGEXP] [NAMEREGEXP]
135 info locals [-q] [-t TYPEREGEXP] [NAMEREGEXP]
136 info variables [-q] [-t TYPEREGEXP] [NAMEREGEXP]
137 These commands can now print only the searched entities
138 matching the provided regexp(s), giving a condition
139 on the entity names or entity types. The flag -q disables
140 printing headers or informations messages.
146 These commands now determine the syntax for the shown entities
147 according to the language chosen by `set language'. In particular,
148 `set language auto' means to automatically choose the language of
151 thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
152 The 'thread apply' command accepts new FLAG arguments.
153 FLAG arguments allow to control what output to produce and how to handle
154 errors raised when applying COMMAND to a thread.
156 set tui tab-width NCHARS
157 show tui tab-width NCHARS
158 "set tui tab-width" replaces the "tabset" command, which has been deprecated.
160 set style enabled [on|off]
162 Enable or disable terminal styling. Styling is enabled by default
163 on most hosts, but disabled by default when in batch mode.
165 set style sources [on|off]
167 Enable or disable source code styling. Source code styling is
168 enabled by default, but only takes effect if styling in general is
169 enabled, and if GDB was linked with GNU Source Highlight.
171 set style filename foreground COLOR
172 set style filename background COLOR
173 set style filename intensity VALUE
174 Control the styling of file names.
176 set style function foreground COLOR
177 set style function background COLOR
178 set style function intensity VALUE
179 Control the styling of function names.
181 set style variable foreground COLOR
182 set style variable background COLOR
183 set style variable intensity VALUE
184 Control the styling of variable names.
186 set style address foreground COLOR
187 set style address background COLOR
188 set style address intensity VALUE
189 Control the styling of addresses.
193 ** The default version of the MI interpreter is now 3 (-i=mi3).
195 ** The '-data-disassemble' MI command now accepts an '-a' option to
196 disassemble the whole function surrounding the given program
197 counter value or function name. Support for this feature can be
198 verified by using the "-list-features" command, which should
199 contain "data-disassemble-a-option".
201 ** Command responses and notifications that include a frame now include
202 the frame's architecture in a new "arch" attribute.
204 ** The output of information about multi-location breakpoints (which is
205 syntactically incorrect in MI 2) has changed in MI 3. This affects
206 the following commands and events:
210 - =breakpoint-created
211 - =breakpoint-modified
213 The -fix-multi-location-breakpoint-output command can be used to enable
214 this behavior with previous MI versions.
216 * New native configurations
218 GNU/Linux/RISC-V riscv*-*-linux*
219 FreeBSD/riscv riscv*-*-freebsd*
223 GNU/Linux/RISC-V riscv*-*-linux*
225 CSKY GNU/LINUX csky*-*-linux
226 FreeBSD/riscv riscv*-*-freebsd*
228 GNU/Linux/OpenRISC or1k*-*-linux*
232 GDB no longer supports native debugging on versions of MS-Windows
237 ** GDB no longer supports Python versions less than 2.6.
239 ** The gdb.Inferior type has a new 'progspace' property, which is the program
240 space associated to that inferior.
242 ** The gdb.Progspace type has a new 'objfiles' method, which returns the list
243 of objfiles associated to that program space.
245 ** gdb.SYMBOL_LOC_COMMON_BLOCK, gdb.SYMBOL_MODULE_DOMAIN, and
246 gdb.SYMBOL_COMMON_BLOCK_DOMAIN were added to reflect changes to
249 ** gdb.SYMBOL_VARIABLES_DOMAIN, gdb.SYMBOL_FUNCTIONS_DOMAIN, and
250 gdb.SYMBOL_TYPES_DOMAIN are now deprecated. These were never
251 correct and did not work properly.
253 ** The gdb.Value type has a new constructor, which is used to construct a
254 gdb.Value from a Python buffer object and a gdb.Type.
260 Enable or disable the undefined behavior sanitizer. This is
261 disabled by default, but passing --enable-ubsan=yes or
262 --enable-ubsan=auto to configure will enable it. Enabling this can
263 cause a performance penalty. The undefined behavior sanitizer was
264 first introduced in GCC 4.9.
266 *** Changes in GDB 8.2
268 * The 'set disassembler-options' command now supports specifying options
271 * The 'symbol-file' command now accepts an '-o' option to add a relative
272 offset to all sections.
274 * Similarly, the 'add-symbol-file' command also accepts an '-o' option to add
275 a relative offset to all sections, but it allows to override the load
276 address of individual sections using '-s'.
278 * The 'add-symbol-file' command no longer requires the second argument
279 (address of the text section).
281 * The endianness used with the 'set endian auto' mode in the absence of
282 an executable selected for debugging is now the last endianness chosen
283 either by one of the 'set endian big' and 'set endian little' commands
284 or by inferring from the last executable used, rather than the startup
287 * The pager now allows a "c" response, meaning to disable the pager
288 for the rest of the current command.
290 * The commands 'info variables/functions/types' now show the source line
291 numbers of symbol definitions when available.
293 * 'info proc' now works on running processes on FreeBSD systems and core
294 files created on FreeBSD systems.
296 * C expressions can now use _Alignof, and C++ expressions can now use
299 * Support for SVE on AArch64 Linux. Note that GDB does not detect changes to
300 the vector length while the process is running.
306 Control display of debugging info regarding the FreeBSD native target.
308 set|show varsize-limit
309 This new setting allows the user to control the maximum size of Ada
310 objects being printed when those objects have a variable type,
311 instead of that maximum size being hardcoded to 65536 bytes.
313 set|show record btrace cpu
314 Controls the processor to be used for enabling errata workarounds for
317 maint check libthread-db
318 Run integrity checks on the current inferior's thread debugging
321 maint set check-libthread-db (on|off)
322 maint show check-libthread-db
323 Control whether to run integrity checks on inferior specific thread
324 debugging libraries as they are loaded. The default is not to
329 ** Type alignment is now exposed via the "align" attribute of a gdb.Type.
331 ** The commands attached to a breakpoint can be set by assigning to
332 the breakpoint's "commands" field.
334 ** gdb.execute can now execute multi-line gdb commands.
336 ** The new functions gdb.convenience_variable and
337 gdb.set_convenience_variable can be used to get and set the value
338 of convenience variables.
340 ** A gdb.Parameter will no longer print the "set" help text on an
341 ordinary "set"; instead by default a "set" will be silent unless
342 the get_set_string method returns a non-empty string.
346 RiscV ELF riscv*-*-elf
348 * Removed targets and native configurations
350 m88k running OpenBSD m88*-*-openbsd*
351 SH-5/SH64 ELF sh64-*-elf*, SH-5/SH64 support in sh*
352 SH-5/SH64 running GNU/Linux SH-5/SH64 support in sh*-*-linux*
353 SH-5/SH64 running OpenBSD SH-5/SH64 support in sh*-*-openbsd*
355 * Aarch64/Linux hardware watchpoints improvements
357 Hardware watchpoints on unaligned addresses are now properly
358 supported when running Linux kernel 4.10 or higher: read and access
359 watchpoints are no longer spuriously missed, and all watchpoints
360 lengths between 1 and 8 bytes are supported. On older kernels,
361 watchpoints set on unaligned addresses are no longer missed, with
362 the tradeoff that there is a possibility of false hits being
367 --enable-codesign=CERT
368 This can be used to invoke "codesign -s CERT" after building gdb.
369 This option is useful on macOS, where code signing is required for
370 gdb to work properly.
372 --disable-gdbcli has been removed
373 This is now silently accepted, but does nothing.
375 *** Changes in GDB 8.1
377 * GDB now supports dynamically creating arbitrary register groups specified
378 in XML target descriptions. This allows for finer grain grouping of
379 registers on systems with a large amount of registers.
381 * The 'ptype' command now accepts a '/o' flag, which prints the
382 offsets and sizes of fields in a struct, like the pahole(1) tool.
384 * New "--readnever" command line option instructs GDB to not read each
385 symbol file's symbolic debug information. This makes startup faster
386 but at the expense of not being able to perform symbolic debugging.
387 This option is intended for use cases where symbolic debugging will
388 not be used, e.g., when you only need to dump the debuggee's core.
390 * GDB now uses the GNU MPFR library, if available, to emulate target
391 floating-point arithmetic during expression evaluation when the target
392 uses different floating-point formats than the host. At least version
393 3.1 of GNU MPFR is required.
395 * GDB now supports access to the guarded-storage-control registers and the
396 software-based guarded-storage broadcast control registers on IBM z14.
398 * On Unix systems, GDB now supports transmitting environment variables
399 that are to be set or unset to GDBserver. These variables will
400 affect the environment to be passed to the remote inferior.
402 To inform GDB of environment variables that are to be transmitted to
403 GDBserver, use the "set environment" command. Only user set
404 environment variables are sent to GDBserver.
406 To inform GDB of environment variables that are to be unset before
407 the remote inferior is started by the GDBserver, use the "unset
408 environment" command.
410 * Completion improvements
412 ** GDB can now complete function parameters in linespecs and
413 explicit locations without quoting. When setting breakpoints,
414 quoting around functions names to help with TAB-completion is
415 generally no longer necessary. For example, this now completes
418 (gdb) b function(in[TAB]
419 (gdb) b function(int)
421 Related, GDB is no longer confused with completing functions in
422 C++ anonymous namespaces:
425 (gdb) b (anonymous namespace)::[TAB][TAB]
426 (anonymous namespace)::a_function()
427 (anonymous namespace)::b_function()
429 ** GDB now has much improved linespec and explicit locations TAB
430 completion support, that better understands what you're
431 completing and offers better suggestions. For example, GDB no
432 longer offers data symbols as possible completions when you're
433 setting a breakpoint.
435 ** GDB now TAB-completes label symbol names.
437 ** The "complete" command now mimics TAB completion accurately.
439 * New command line options (gcore)
442 Dump all memory mappings.
444 * Breakpoints on C++ functions are now set on all scopes by default
446 By default, breakpoints on functions/methods are now interpreted as
447 specifying all functions with the given name ignoring missing
448 leading scopes (namespaces and classes).
450 For example, assuming a C++ program with symbols named:
455 both commands "break func()" and "break B::func()" set a breakpoint
458 You can use the new flag "-qualified" to override this. This makes
459 GDB interpret the specified function name as a complete
460 fully-qualified name instead. For example, using the same C++
461 program, the "break -q B::func" command sets a breakpoint on
462 "B::func", only. A parameter has been added to the Python
463 gdb.Breakpoint constructor to achieve the same result when creating
464 a breakpoint from Python.
466 * Breakpoints on functions marked with C++ ABI tags
468 GDB can now set breakpoints on functions marked with C++ ABI tags
469 (e.g., [abi:cxx11]). See here for a description of ABI tags:
470 https://developers.redhat.com/blog/2015/02/05/gcc5-and-the-c11-abi/
472 Functions with a C++11 abi tag are demangled/displayed like this:
474 function[abi:cxx11](int)
477 You can now set a breakpoint on such functions simply as if they had
480 (gdb) b function(int)
482 Or if you need to disambiguate between tags, like:
484 (gdb) b function[abi:other_tag](int)
486 Tab completion was adjusted accordingly as well.
490 ** New events gdb.new_inferior, gdb.inferior_deleted, and
491 gdb.new_thread are emitted. See the manual for further
492 description of these.
494 ** A new function, "gdb.rbreak" has been added to the Python API.
495 This function allows the setting of a large number of breakpoints
496 via a regex pattern in Python. See the manual for further details.
498 ** Python breakpoints can now accept explicit locations. See the
499 manual for a further description of this feature.
502 * New features in the GDB remote stub, GDBserver
504 ** GDBserver is now able to start inferior processes with a
505 specified initial working directory.
507 The user can set the desired working directory to be used from
508 GDB using the new "set cwd" command.
510 ** New "--selftest" command line option runs some GDBserver self
511 tests. These self tests are disabled in releases.
513 ** On Unix systems, GDBserver now does globbing expansion and variable
514 substitution in inferior command line arguments.
516 This is done by starting inferiors using a shell, like GDB does.
517 See "set startup-with-shell" in the user manual for how to disable
518 this from GDB when using "target extended-remote". When using
519 "target remote", you can disable the startup with shell by using the
520 new "--no-startup-with-shell" GDBserver command line option.
522 ** On Unix systems, GDBserver now supports receiving environment
523 variables that are to be set or unset from GDB. These variables
524 will affect the environment to be passed to the inferior.
526 * When catching an Ada exception raised with a message, GDB now prints
527 the message in the catchpoint hit notification. In GDB/MI mode, that
528 information is provided as an extra field named "exception-message"
529 in the *stopped notification.
531 * Trait objects can now be inspected When debugging Rust code. This
532 requires compiler support which will appear in Rust 1.24.
536 QEnvironmentHexEncoded
537 Inform GDBserver of an environment variable that is to be passed to
538 the inferior when starting it.
541 Inform GDBserver of an environment variable that is to be unset
542 before starting the remote inferior.
545 Inform GDBserver that the environment should be reset (i.e.,
546 user-set environment variables should be unset).
549 Indicates whether the inferior must be started with a shell or not.
552 Tell GDBserver that the inferior to be started should use a specific
555 * The "maintenance print c-tdesc" command now takes an optional
556 argument which is the file name of XML target description.
558 * The "maintenance selftest" command now takes an optional argument to
559 filter the tests to be run.
561 * The "enable", and "disable" commands now accept a range of
562 breakpoint locations, e.g. "enable 1.3-5".
567 Set and show the current working directory for the inferior.
570 Set and show compilation command used for compiling and injecting code
571 with the 'compile' commands.
573 set debug separate-debug-file
574 show debug separate-debug-file
575 Control the display of debug output about separate debug file search.
577 set dump-excluded-mappings
578 show dump-excluded-mappings
579 Control whether mappings marked with the VM_DONTDUMP flag should be
580 dumped when generating a core file.
583 List the registered selftests.
586 Start the debugged program stopping at the first instruction.
589 Control display of debugging messages related to OpenRISC targets.
591 set|show print type nested-type-limit
592 Set and show the limit of nesting level for nested types that the
593 type printer will show.
595 * TUI Single-Key mode now supports two new shortcut keys: `i' for stepi and
598 * Safer/improved support for debugging with no debug info
600 GDB no longer assumes functions with no debug information return
603 This means that GDB now refuses to call such functions unless you
604 tell it the function's type, by either casting the call to the
605 declared return type, or by casting the function to a function
606 pointer of the right type, and calling that:
608 (gdb) p getenv ("PATH")
609 'getenv' has unknown return type; cast the call to its declared return type
610 (gdb) p (char *) getenv ("PATH")
611 $1 = 0x7fffffffe "/usr/local/bin:/"...
612 (gdb) p ((char * (*) (const char *)) getenv) ("PATH")
613 $2 = 0x7fffffffe "/usr/local/bin:/"...
615 Similarly, GDB no longer assumes that global variables with no debug
616 info have type 'int', and refuses to print the variable's value
617 unless you tell it the variable's type:
620 'var' has unknown type; cast it to its declared type
624 * New native configurations
626 FreeBSD/aarch64 aarch64*-*-freebsd*
627 FreeBSD/arm arm*-*-freebsd*
631 FreeBSD/aarch64 aarch64*-*-freebsd*
632 FreeBSD/arm arm*-*-freebsd*
633 OpenRISC ELF or1k*-*-elf
635 * Removed targets and native configurations
637 Solaris 2.0-9 i?86-*-solaris2.[0-9], sparc*-*-solaris2.[0-9]
639 *** Changes in GDB 8.0
641 * GDB now supports access to the PKU register on GNU/Linux. The register is
642 added by the Memory Protection Keys for Userspace feature which will be
643 available in future Intel CPUs.
645 * GDB now supports C++11 rvalue references.
649 ** New functions to start, stop and access a running btrace recording.
650 ** Rvalue references are now supported in gdb.Type.
652 * GDB now supports recording and replaying rdrand and rdseed Intel 64
655 * Building GDB and GDBserver now requires a C++11 compiler.
657 For example, GCC 4.8 or later.
659 It is no longer possible to build GDB or GDBserver with a C
660 compiler. The --disable-build-with-cxx configure option has been
663 * Building GDB and GDBserver now requires GNU make >= 3.81.
665 It is no longer supported to build GDB or GDBserver with another
666 implementation of the make program or an earlier version of GNU make.
668 * Native debugging on MS-Windows supports command-line redirection
670 Command-line arguments used for starting programs on MS-Windows can
671 now include redirection symbols supported by native Windows shells,
672 such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such
673 as "run", "start", and "set args", as well as the corresponding MI
676 * Support for thread names on MS-Windows.
678 GDB now catches and handles the special exception that programs
679 running on MS-Windows use to assign names to threads in the
682 * Support for Java programs compiled with gcj has been removed.
684 * User commands now accept an unlimited number of arguments.
685 Previously, only up to 10 was accepted.
687 * The "eval" command now expands user-defined command arguments.
689 This makes it easier to process a variable number of arguments:
694 eval "print $arg%d", $i
699 * Target descriptions can now describe registers for sparc32 and sparc64.
701 * GDB now supports DWARF version 5 (debug information format).
702 Its .debug_names index is not yet supported.
704 * New native configurations
706 FreeBSD/mips mips*-*-freebsd
710 Synopsys ARC arc*-*-elf32
711 FreeBSD/mips mips*-*-freebsd
713 * Removed targets and native configurations
715 Alpha running FreeBSD alpha*-*-freebsd*
716 Alpha running GNU/kFreeBSD alpha*-*-kfreebsd*-gnu
721 Erases all the flash memory regions reported by the target.
723 maint print arc arc-instruction address
724 Print internal disassembler information about instruction at a given address.
728 set disassembler-options
729 show disassembler-options
730 Controls the passing of target specific information to the disassembler.
731 If it is necessary to specify more than one disassembler option then
732 multiple options can be placed together into a comma separated list.
733 The default value is the empty string. Currently, the only supported
734 targets are ARM, PowerPC and S/390.
739 Erases all the flash memory regions reported by the target. This is
740 equivalent to the CLI command flash-erase.
742 -file-list-shared-libraries
743 List the shared libraries in the program. This is
744 equivalent to the CLI command "info shared".
747 Catchpoints stopping the program when Ada exceptions are
748 handled. This is equivalent to the CLI command "catch handlers".
750 *** Changes in GDB 7.12
752 * GDB and GDBserver now build with a C++ compiler by default.
754 The --enable-build-with-cxx configure option is now enabled by
755 default. One must now explicitly configure with
756 --disable-build-with-cxx in order to build with a C compiler. This
757 option will be removed in a future release.
759 * GDBserver now supports recording btrace without maintaining an active
762 * GDB now supports a negative repeat count in the 'x' command to examine
763 memory backward from the given address. For example:
766 #0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4
767 #1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8
768 (gdb) x/-5i 0x0000000000400580
769 0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)
770 0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
771 0x400571 <main(int, char**)+15>: mov $0x40061c,%esi
772 0x400576 <main(int, char**)+20>: mov $0x2a,%edi
773 0x40057b <main(int, char**)+25>:
774 callq 0x400536 <Func1(int, char const*)>
776 * Fortran: Support structures with fields of dynamic types and
777 arrays of dynamic types.
779 * The symbol dumping maintenance commands have new syntax.
780 maint print symbols [-pc address] [--] [filename]
781 maint print symbols [-objfile objfile] [-source source] [--] [filename]
782 maint print psymbols [-objfile objfile] [-pc address] [--] [filename]
783 maint print psymbols [-objfile objfile] [-source source] [--] [filename]
784 maint print msymbols [-objfile objfile] [--] [filename]
786 * GDB now supports multibit bitfields and enums in target register
789 * New Python-based convenience function $_as_string(val), which returns
790 the textual representation of a value. This function is especially
791 useful to obtain the text label of an enum value.
793 * Intel MPX bound violation handling.
795 Segmentation faults caused by a Intel MPX boundary violation
796 now display the kind of violation (upper or lower), the memory
797 address accessed and the memory bounds, along with the usual
798 signal received and code location.
802 Program received signal SIGSEGV, Segmentation fault
803 Upper bound violation while accessing address 0x7fffffffc3b3
804 Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
805 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
807 * Rust language support.
808 GDB now supports debugging programs written in the Rust programming
809 language. See https://www.rust-lang.org/ for more information about
812 * Support for running interpreters on specified input/output devices
814 GDB now supports a new mechanism that allows frontends to provide
815 fully featured GDB console views, as a better alternative to
816 building such views on top of the "-interpreter-exec console"
817 command. See the new "new-ui" command below. With that command,
818 frontends can now start GDB in the traditional command-line mode
819 running in an embedded terminal emulator widget, and create a
820 separate MI interpreter running on a specified i/o device. In this
821 way, GDB handles line editing, history, tab completion, etc. in the
822 console all by itself, and the GUI uses the separate MI interpreter
823 for its own control and synchronization, invisible to the command
826 * The "catch syscall" command catches groups of related syscalls.
828 The "catch syscall" command now supports catching a group of related
829 syscalls using the 'group:' or 'g:' prefix.
834 skip -gfile file-glob-pattern
835 skip -function function
836 skip -rfunction regular-expression
837 A generalized form of the skip command, with new support for
838 glob-style file names and regular expressions for function names.
839 Additionally, a file spec and a function spec may now be combined.
841 maint info line-table REGEXP
842 Display the contents of GDB's internal line table data struture.
845 Run any GDB unit tests that were compiled in.
848 Start a new user interface instance running INTERP as interpreter,
849 using the TTY file for input/output.
853 ** gdb.Breakpoint objects have a new attribute "pending", which
854 indicates whether the breakpoint is pending.
855 ** Three new breakpoint-related events have been added:
856 gdb.breakpoint_created, gdb.breakpoint_modified, and
857 gdb.breakpoint_deleted.
860 Signal ("set") the given MS-Windows event object. This is used in
861 conjunction with the Windows JIT debugging (AeDebug) support, where
862 the OS suspends a crashing process until a debugger can attach to
863 it. Resuming the crashing process, in order to debug it, is done by
866 * Support for tracepoints and fast tracepoints on s390-linux and s390x-linux
867 was added in GDBserver, including JIT compiling fast tracepoint's
868 conditional expression bytecode into native code.
870 * Support for various remote target protocols and ROM monitors has
873 target m32rsdi Remote M32R debugging over SDI
874 target mips MIPS remote debugging protocol
875 target pmon PMON ROM monitor
876 target ddb NEC's DDB variant of PMON for Vr4300
877 target rockhopper NEC RockHopper variant of PMON
878 target lsi LSI variant of PMO
880 * Support for tracepoints and fast tracepoints on powerpc-linux,
881 powerpc64-linux, and powerpc64le-linux was added in GDBserver,
882 including JIT compiling fast tracepoint's conditional expression
883 bytecode into native code.
885 * MI async record =record-started now includes the method and format used for
886 recording. For example:
888 =record-started,thread-group="i1",method="btrace",format="bts"
890 * MI async record =thread-selected now includes the frame field. For example:
892 =thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}
896 Andes NDS32 nds32*-*-elf
898 *** Changes in GDB 7.11
900 * GDB now supports debugging kernel-based threads on FreeBSD.
902 * Per-inferior thread numbers
904 Thread numbers are now per inferior instead of global. If you're
905 debugging multiple inferiors, GDB displays thread IDs using a
906 qualified INF_NUM.THR_NUM form. For example:
910 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
911 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
912 * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
913 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
915 As consequence, thread numbers as visible in the $_thread
916 convenience variable and in Python's InferiorThread.num attribute
917 are no longer unique between inferiors.
919 GDB now maintains a second thread ID per thread, referred to as the
920 global thread ID, which is the new equivalent of thread numbers in
921 previous releases. See also $_gthread below.
923 For backwards compatibility, MI's thread IDs always refer to global
926 * Commands that accept thread IDs now accept the qualified
927 INF_NUM.THR_NUM form as well. For example:
930 [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
933 * In commands that accept a list of thread IDs, you can now refer to
934 all threads of an inferior using a star wildcard. GDB accepts
935 "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
936 refer to all threads of the current inferior. For example, "info
939 * You can use "info threads -gid" to display the global thread ID of
942 * The new convenience variable $_gthread holds the global number of
945 * The new convenience variable $_inferior holds the number of the
948 * GDB now displays the ID and name of the thread that hit a breakpoint
949 or received a signal, if your program is multi-threaded. For
952 Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
953 Thread 1 "main" received signal SIGINT, Interrupt.
955 * Record btrace now supports non-stop mode.
957 * Support for tracepoints on aarch64-linux was added in GDBserver.
959 * The 'record instruction-history' command now indicates speculative execution
960 when using the Intel Processor Trace recording format.
962 * GDB now allows users to specify explicit locations, bypassing
963 the linespec parser. This feature is also available to GDB/MI
966 * Multi-architecture debugging is supported on AArch64 GNU/Linux.
967 GDB now is able to debug both AArch64 applications and ARM applications
970 * Support for fast tracepoints on aarch64-linux was added in GDBserver,
971 including JIT compiling fast tracepoint's conditional expression bytecode
974 * GDB now supports displaced stepping on AArch64 GNU/Linux.
976 * "info threads", "info inferiors", "info display", "info checkpoints"
977 and "maint info program-spaces" now list the corresponding items in
978 ascending ID order, for consistency with all other "info" commands.
980 * In Ada, the overloads selection menu has been enhanced to display the
981 parameter types and the return types for the matching overloaded subprograms.
985 maint set target-non-stop (on|off|auto)
986 maint show target-non-stop
987 Control whether GDB targets always operate in non-stop mode even if
988 "set non-stop" is "off". The default is "auto", meaning non-stop
989 mode is enabled if supported by the target.
991 maint set bfd-sharing
992 maint show bfd-sharing
993 Control the reuse of bfd objects.
997 Control display of debugging info regarding bfd caching.
1001 Control display of debugging info regarding FreeBSD threads.
1003 set remote multiprocess-extensions-packet
1004 show remote multiprocess-extensions-packet
1005 Set/show the use of the remote protocol multiprocess extensions.
1007 set remote thread-events
1008 show remote thread-events
1009 Set/show the use of thread create/exit events.
1011 set ada print-signatures on|off
1012 show ada print-signatures"
1013 Control whether parameter types and return types are displayed in overloads
1014 selection menus. It is activaled (@code{on}) by default.
1018 Controls the maximum size of memory, in bytes, that GDB will
1019 allocate for value contents. Prevents incorrect programs from
1020 causing GDB to allocate overly large buffers. Default is 64k.
1022 * The "disassemble" command accepts a new modifier: /s.
1023 It prints mixed source+disassembly like /m with two differences:
1024 - disassembled instructions are now printed in program order, and
1025 - and source for all relevant files is now printed.
1026 The "/m" option is now considered deprecated: its "source-centric"
1027 output hasn't proved useful in practice.
1029 * The "record instruction-history" command accepts a new modifier: /s.
1030 It behaves exactly like /m and prints mixed source+disassembly.
1032 * The "set scheduler-locking" command supports a new mode "replay".
1033 It behaves like "off" in record mode and like "on" in replay mode.
1035 * Support for various ROM monitors has been removed:
1037 target dbug dBUG ROM monitor for Motorola ColdFire
1038 target picobug Motorola picobug monitor
1039 target dink32 DINK32 ROM monitor for PowerPC
1040 target m32r Renesas M32R/D ROM monitor
1041 target mon2000 mon2000 ROM monitor
1042 target ppcbug PPCBUG ROM monitor for PowerPC
1044 * Support for reading/writing memory and extracting values on architectures
1045 whose memory is addressable in units of any integral multiple of 8 bits.
1048 Allows to break when an Ada exception is handled.
1050 * New remote packets
1053 Indicates that an exec system call was executed.
1055 exec-events feature in qSupported
1056 The qSupported packet allows GDB to request support for exec
1057 events using the new 'gdbfeature' exec-event, and the qSupported
1058 response can contain the corresponding 'stubfeature'. Set and
1059 show commands can be used to display whether these features are enabled.
1062 Equivalent to interrupting with the ^C character, but works in
1065 thread created stop reason (T05 create:...)
1066 Indicates that the thread was just created and is stopped at entry.
1068 thread exit stop reply (w exitcode;tid)
1069 Indicates that the thread has terminated.
1072 Enables/disables thread create and exit event reporting. For
1073 example, this is used in non-stop mode when GDB stops a set of
1074 threads and synchronously waits for the their corresponding stop
1075 replies. Without exit events, if one of the threads exits, GDB
1076 would hang forever not knowing that it should no longer expect a
1077 stop for that same thread.
1080 Indicates that there are no resumed threads left in the target (all
1081 threads are stopped). The remote stub reports support for this stop
1082 reply to GDB's qSupported query.
1085 Enables/disables catching syscalls from the inferior process.
1086 The remote stub reports support for this packet to GDB's qSupported query.
1088 syscall_entry stop reason
1089 Indicates that a syscall was just called.
1091 syscall_return stop reason
1092 Indicates that a syscall just returned.
1094 * Extended-remote exec events
1096 ** GDB now has support for exec events on extended-remote Linux targets.
1097 For such targets with Linux kernels 2.5.46 and later, this enables
1098 follow-exec-mode and exec catchpoints.
1100 set remote exec-event-feature-packet
1101 show remote exec-event-feature-packet
1102 Set/show the use of the remote exec event feature.
1104 * Thread names in remote protocol
1106 The reply to qXfer:threads:read may now include a name attribute for each
1109 * Target remote mode fork and exec events
1111 ** GDB now has support for fork and exec events on target remote mode
1112 Linux targets. For such targets with Linux kernels 2.5.46 and later,
1113 this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
1114 fork and exec catchpoints.
1116 * Remote syscall events
1118 ** GDB now has support for catch syscall on remote Linux targets,
1119 currently enabled on x86/x86_64 architectures.
1121 set remote catch-syscall-packet
1122 show remote catch-syscall-packet
1123 Set/show the use of the remote catch syscall feature.
1127 ** The -var-set-format command now accepts the zero-hexadecimal
1128 format. It outputs data in hexadecimal format with zero-padding on the
1133 ** gdb.InferiorThread objects have a new attribute "global_num",
1134 which refers to the thread's global thread ID. The existing
1135 "num" attribute now refers to the thread's per-inferior number.
1136 See "Per-inferior thread numbers" above.
1137 ** gdb.InferiorThread objects have a new attribute "inferior", which
1138 is the Inferior object the thread belongs to.
1140 *** Changes in GDB 7.10
1142 * Support for process record-replay and reverse debugging on aarch64*-linux*
1143 targets has been added. GDB now supports recording of A64 instruction set
1144 including advance SIMD instructions.
1146 * Support for Sun's version of the "stabs" debug file format has been removed.
1148 * GDB now honors the content of the file /proc/PID/coredump_filter
1149 (PID is the process ID) on GNU/Linux systems. This file can be used
1150 to specify the types of memory mappings that will be included in a
1151 corefile. For more information, please refer to the manual page of
1152 "core(5)". GDB also has a new command: "set use-coredump-filter
1153 on|off". It allows to set whether GDB will read the content of the
1154 /proc/PID/coredump_filter file when generating a corefile.
1156 * The "info os" command on GNU/Linux can now display information on
1158 "info os cpus" Listing of all cpus/cores on the system
1160 * GDB has two new commands: "set serial parity odd|even|none" and
1161 "show serial parity". These allows to set or show parity for the
1164 * The "info source" command now displays the producer string if it was
1165 present in the debug info. This typically includes the compiler version
1166 and may include things like its command line arguments.
1168 * The "info dll", an alias of the "info sharedlibrary" command,
1169 is now available on all platforms.
1171 * Directory names supplied to the "set sysroot" commands may be
1172 prefixed with "target:" to tell GDB to access shared libraries from
1173 the target system, be it local or remote. This replaces the prefix
1174 "remote:". The default sysroot has been changed from "" to
1175 "target:". "remote:" is automatically converted to "target:" for
1176 backward compatibility.
1178 * The system root specified by "set sysroot" will be prepended to the
1179 filename of the main executable (if reported to GDB as absolute by
1180 the operating system) when starting processes remotely, and when
1181 attaching to already-running local or remote processes.
1183 * GDB now supports automatic location and retrieval of executable
1184 files from remote targets. Remote debugging can now be initiated
1185 using only a "target remote" or "target extended-remote" command
1186 (no "set sysroot" or "file" commands are required). See "New remote
1189 * The "dump" command now supports verilog hex format.
1191 * GDB now supports the vector ABI on S/390 GNU/Linux targets.
1193 * On GNU/Linux, GDB and gdbserver are now able to access executable
1194 and shared library files without a "set sysroot" command when
1195 attaching to processes running in different mount namespaces from
1196 the debugger. This makes it possible to attach to processes in
1197 containers as simply as "gdb -p PID" or "gdbserver --attach PID".
1198 See "New remote packets" below.
1200 * The "tui reg" command now provides completion for all of the
1201 available register groups, including target specific groups.
1203 * The HISTSIZE environment variable is no longer read when determining
1204 the size of GDB's command history. GDB now instead reads the dedicated
1205 GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
1206 disables truncation of command history. Non-numeric values of GDBHISTSIZE
1211 ** Memory ports can now be unbuffered.
1215 ** gdb.Objfile objects have a new attribute "username",
1216 which is the name of the objfile as specified by the user,
1217 without, for example, resolving symlinks.
1218 ** You can now write frame unwinders in Python.
1219 ** gdb.Type objects have a new method "optimized_out",
1220 returning optimized out gdb.Value instance of this type.
1221 ** gdb.Value objects have new methods "reference_value" and
1222 "const_value" which return a reference to the value and a
1223 "const" version of the value respectively.
1227 maint print symbol-cache
1228 Print the contents of the symbol cache.
1230 maint print symbol-cache-statistics
1231 Print statistics of symbol cache usage.
1233 maint flush-symbol-cache
1234 Flush the contents of the symbol cache.
1238 Start branch trace recording using Branch Trace Store (BTS) format.
1241 Evaluate expression by using the compiler and print result.
1245 Explicit commands for enabling and disabling tui mode.
1248 set mpx bound on i386 and amd64
1249 Support for bound table investigation on Intel MPX enabled applications.
1253 Start branch trace recording using Intel Processor Trace format.
1256 Print information about branch tracing internals.
1258 maint btrace packet-history
1259 Print the raw branch tracing data.
1261 maint btrace clear-packet-history
1262 Discard the stored raw branch tracing data.
1265 Discard all branch tracing data. It will be fetched and processed
1266 anew by the next "record" command.
1271 Renamed from "set debug dwarf2-die".
1272 show debug dwarf-die
1273 Renamed from "show debug dwarf2-die".
1275 set debug dwarf-read
1276 Renamed from "set debug dwarf2-read".
1277 show debug dwarf-read
1278 Renamed from "show debug dwarf2-read".
1280 maint set dwarf always-disassemble
1281 Renamed from "maint set dwarf2 always-disassemble".
1282 maint show dwarf always-disassemble
1283 Renamed from "maint show dwarf2 always-disassemble".
1285 maint set dwarf max-cache-age
1286 Renamed from "maint set dwarf2 max-cache-age".
1287 maint show dwarf max-cache-age
1288 Renamed from "maint show dwarf2 max-cache-age".
1290 set debug dwarf-line
1291 show debug dwarf-line
1292 Control display of debugging info regarding DWARF line processing.
1295 show max-completions
1296 Set the maximum number of candidates to be considered during
1297 completion. The default value is 200. This limit allows GDB
1298 to avoid generating large completion lists, the computation of
1299 which can cause the debugger to become temporarily unresponsive.
1301 set history remove-duplicates
1302 show history remove-duplicates
1303 Control the removal of duplicate history entries.
1305 maint set symbol-cache-size
1306 maint show symbol-cache-size
1307 Control the size of the symbol cache.
1309 set|show record btrace bts buffer-size
1310 Set and show the size of the ring buffer used for branch tracing in
1312 The obtained size may differ from the requested size. Use "info
1313 record" to see the obtained buffer size.
1315 set debug linux-namespaces
1316 show debug linux-namespaces
1317 Control display of debugging info regarding Linux namespaces.
1319 set|show record btrace pt buffer-size
1320 Set and show the size of the ring buffer used for branch tracing in
1321 Intel Processor Trace format.
1322 The obtained size may differ from the requested size. Use "info
1323 record" to see the obtained buffer size.
1325 maint set|show btrace pt skip-pad
1326 Set and show whether PAD packets are skipped when computing the
1329 * The command 'thread apply all' can now support new option '-ascending'
1330 to call its specified command for all threads in ascending order.
1332 * Python/Guile scripting
1334 ** GDB now supports auto-loading of Python/Guile scripts contained in the
1335 special section named `.debug_gdb_scripts'.
1337 * New remote packets
1339 qXfer:btrace-conf:read
1340 Return the branch trace configuration for the current thread.
1342 Qbtrace-conf:bts:size
1343 Set the requested ring buffer size for branch tracing in BTS format.
1346 Enable Intel Procesor Trace-based branch tracing for the current
1347 process. The remote stub reports support for this packet to GDB's
1350 Qbtrace-conf:pt:size
1351 Set the requested ring buffer size for branch tracing in Intel Processor
1355 Indicates a memory breakpoint instruction was executed, irrespective
1356 of whether it was GDB that planted the breakpoint or the breakpoint
1357 is hardcoded in the program. This is required for correct non-stop
1361 Indicates the target stopped for a hardware breakpoint. This is
1362 required for correct non-stop mode operation.
1365 Return information about files on the remote system.
1367 qXfer:exec-file:read
1368 Return the full absolute name of the file that was executed to
1369 create a process running on the remote system.
1372 Select the filesystem on which vFile: operations with filename
1373 arguments will operate. This is required for GDB to be able to
1374 access files on remote targets where the remote stub does not
1375 share a common filesystem with the inferior(s).
1378 Indicates that a fork system call was executed.
1381 Indicates that a vfork system call was executed.
1383 vforkdone stop reason
1384 Indicates that a vfork child of the specified process has executed
1385 an exec or exit, allowing the vfork parent to resume execution.
1387 fork-events and vfork-events features in qSupported
1388 The qSupported packet allows GDB to request support for fork and
1389 vfork events using new 'gdbfeatures' fork-events and vfork-events,
1390 and the qSupported response can contain the corresponding
1391 'stubfeatures'. Set and show commands can be used to display
1392 whether these features are enabled.
1394 * Extended-remote fork events
1396 ** GDB now has support for fork events on extended-remote Linux
1397 targets. For targets with Linux kernels 2.5.60 and later, this
1398 enables follow-fork-mode and detach-on-fork for both fork and
1399 vfork, as well as fork and vfork catchpoints.
1401 * The info record command now shows the recording format and the
1402 branch tracing configuration for the current thread when using
1403 the btrace record target.
1404 For the BTS format, it shows the ring buffer size.
1406 * GDB now has support for DTrace USDT (Userland Static Defined
1407 Tracing) probes. The supported targets are x86_64-*-linux-gnu.
1409 * GDB now supports access to vector registers on S/390 GNU/Linux
1412 * Removed command line options
1414 -xdb HP-UX XDB compatibility mode.
1416 * Removed targets and native configurations
1418 HP/PA running HP-UX hppa*-*-hpux*
1419 Itanium running HP-UX ia64-*-hpux*
1421 * New configure options
1424 This configure option allows the user to build GDB with support for
1425 Intel Processor Trace (default: auto). This requires libipt.
1427 --with-libipt-prefix=PATH
1428 Specify the path to the version of libipt that GDB should use.
1429 $PATH/include should contain the intel-pt.h header and
1430 $PATH/lib should contain the libipt.so library.
1432 *** Changes in GDB 7.9.1
1436 ** Xmethods can now specify a result type.
1438 *** Changes in GDB 7.9
1440 * GDB now supports hardware watchpoints on x86 GNU Hurd.
1444 ** You can now access frame registers from Python scripts.
1445 ** New attribute 'producer' for gdb.Symtab objects.
1446 ** gdb.Objfile objects have a new attribute "progspace",
1447 which is the gdb.Progspace object of the containing program space.
1448 ** gdb.Objfile objects have a new attribute "owner".
1449 ** gdb.Objfile objects have a new attribute "build_id",
1450 which is the build ID generated when the file was built.
1451 ** gdb.Objfile objects have a new method "add_separate_debug_file".
1452 ** A new event "gdb.clear_objfiles" has been added, triggered when
1453 selecting a new file to debug.
1454 ** You can now add attributes to gdb.Objfile and gdb.Progspace objects.
1455 ** New function gdb.lookup_objfile.
1457 New events which are triggered when GDB modifies the state of the
1460 ** gdb.events.inferior_call_pre: Function call is about to be made.
1461 ** gdb.events.inferior_call_post: Function call has just been made.
1462 ** gdb.events.memory_changed: A memory location has been altered.
1463 ** gdb.events.register_changed: A register has been altered.
1465 * New Python-based convenience functions:
1467 ** $_caller_is(name [, number_of_frames])
1468 ** $_caller_matches(regexp [, number_of_frames])
1469 ** $_any_caller_is(name [, number_of_frames])
1470 ** $_any_caller_matches(regexp [, number_of_frames])
1472 * GDB now supports the compilation and injection of source code into
1473 the inferior. GDB will use GCC 5.0 or higher built with libcc1.so
1474 to compile the source code to object code, and if successful, inject
1475 and execute that code within the current context of the inferior.
1476 Currently the C language is supported. The commands used to
1477 interface with this new feature are:
1479 compile code [-raw|-r] [--] [source code]
1480 compile file [-raw|-r] filename
1484 demangle [-l language] [--] name
1485 Demangle "name" in the specified language, or the current language
1486 if elided. This command is renamed from the "maint demangle" command.
1487 The latter is kept as a no-op to avoid "maint demangle" being interpreted
1488 as "maint demangler-warning".
1490 queue-signal signal-name-or-number
1491 Queue a signal to be delivered to the thread when it is resumed.
1493 add-auto-load-scripts-directory directory
1494 Add entries to the list of directories from which to load auto-loaded
1497 maint print user-registers
1498 List all currently available "user" registers.
1500 compile code [-r|-raw] [--] [source code]
1501 Compile, inject, and execute in the inferior the executable object
1502 code produced by compiling the provided source code.
1504 compile file [-r|-raw] filename
1505 Compile and inject into the inferior the executable object code
1506 produced by compiling the source code stored in the filename
1509 * On resume, GDB now always passes the signal the program had stopped
1510 for to the thread the signal was sent to, even if the user changed
1511 threads before resuming. Previously GDB would often (but not
1512 always) deliver the signal to the thread that happens to be current
1515 * Conversely, the "signal" command now consistently delivers the
1516 requested signal to the current thread. GDB now asks for
1517 confirmation if the program had stopped for a signal and the user
1518 switched threads meanwhile.
1520 * "breakpoint always-inserted" modes "off" and "auto" merged.
1522 Now, when 'breakpoint always-inserted mode' is set to "off", GDB
1523 won't remove breakpoints from the target until all threads stop,
1524 even in non-stop mode. The "auto" mode has been removed, and "off"
1525 is now the default mode.
1529 set debug symbol-lookup
1530 show debug symbol-lookup
1531 Control display of debugging info regarding symbol lookup.
1535 ** The -list-thread-groups command outputs an exit-code field for
1536 inferiors that have exited.
1540 MIPS SDE mips*-sde*-elf*
1544 Support for these obsolete configurations has been removed.
1546 Alpha running OSF/1 (or Tru64) alpha*-*-osf*
1547 SGI Irix-5.x mips-*-irix5*
1548 SGI Irix-6.x mips-*-irix6*
1549 VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*
1550 VAX running Ultrix vax-*-ultrix*
1552 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1553 and "assf"), have been removed. Use the "sharedlibrary" command, or
1554 its alias "share", instead.
1556 *** Changes in GDB 7.8
1558 * New command line options
1561 This is an alias for the --data-directory option.
1563 * GDB supports printing and modifying of variable length automatic arrays
1564 as specified in ISO C99.
1566 * The ARM simulator now supports instruction level tracing
1567 with or without disassembly.
1571 GDB now has support for scripting using Guile. Whether this is
1572 available is determined at configure time.
1573 Guile version 2.0 or greater is required.
1574 Guile version 2.0.9 is well tested, earlier 2.0 versions are not.
1576 * New commands (for set/show, see "New options" below)
1580 Invoke CODE by passing it to the Guile interpreter.
1584 Start a Guile interactive prompt (or "repl" for "read-eval-print loop").
1586 info auto-load guile-scripts [regexp]
1587 Print the list of automatically loaded Guile scripts.
1589 * The source command is now capable of sourcing Guile scripts.
1590 This feature is dependent on the debugger being built with Guile support.
1594 set print symbol-loading (off|brief|full)
1595 show print symbol-loading
1596 Control whether to print informational messages when loading symbol
1597 information for a file. The default is "full", but when debugging
1598 programs with large numbers of shared libraries the amount of output
1599 becomes less useful.
1601 set guile print-stack (none|message|full)
1602 show guile print-stack
1603 Show a stack trace when an error is encountered in a Guile script.
1605 set auto-load guile-scripts (on|off)
1606 show auto-load guile-scripts
1607 Control auto-loading of Guile script files.
1609 maint ada set ignore-descriptive-types (on|off)
1610 maint ada show ignore-descriptive-types
1611 Control whether the debugger should ignore descriptive types in Ada
1612 programs. The default is not to ignore the descriptive types. See
1613 the user manual for more details on descriptive types and the intended
1614 usage of this option.
1616 set auto-connect-native-target
1618 Control whether GDB is allowed to automatically connect to the
1619 native target for the run, attach, etc. commands when not connected
1620 to any target yet. See also "target native" below.
1622 set record btrace replay-memory-access (read-only|read-write)
1623 show record btrace replay-memory-access
1624 Control what memory accesses are allowed during replay.
1626 maint set target-async (on|off)
1627 maint show target-async
1628 This controls whether GDB targets operate in synchronous or
1629 asynchronous mode. Normally the default is asynchronous, if it is
1630 available; but this can be changed to more easily debug problems
1631 occurring only in synchronous mode.
1633 set mi-async (on|off)
1635 Control whether MI asynchronous mode is preferred. This supersedes
1636 "set target-async" of previous GDB versions.
1638 * "set target-async" is deprecated as a CLI option and is now an alias
1639 for "set mi-async" (only puts MI into async mode).
1641 * Background execution commands (e.g., "c&", "s&", etc.) are now
1642 possible ``out of the box'' if the target supports them. Previously
1643 the user would need to explicitly enable the possibility with the
1644 "set target-async on" command.
1646 * New features in the GDB remote stub, GDBserver
1648 ** New option --debug-format=option1[,option2,...] allows one to add
1649 additional text to each output. At present only timestamps
1650 are supported: --debug-format=timestamps.
1651 Timestamps can also be turned on with the
1652 "monitor set debug-format timestamps" command from GDB.
1654 * The 'record instruction-history' command now starts counting instructions
1655 at one. This also affects the instruction ranges reported by the
1656 'record function-call-history' command when given the /i modifier.
1658 * The command 'record function-call-history' supports a new modifier '/c' to
1659 indent the function names based on their call stack depth.
1660 The fields for the '/i' and '/l' modifier have been reordered.
1661 The source line range is now prefixed with 'at'.
1662 The instruction range is now prefixed with 'inst'.
1663 Both ranges are now printed as '<from>, <to>' to allow copy&paste to the
1664 "record instruction-history" and "list" commands.
1666 * The ranges given as arguments to the 'record function-call-history' and
1667 'record instruction-history' commands are now inclusive.
1669 * The btrace record target now supports the 'record goto' command.
1670 For locations inside the execution trace, the back trace is computed
1671 based on the information stored in the execution trace.
1673 * The btrace record target supports limited reverse execution and replay.
1674 The target does not record data and therefore does not allow reading
1675 memory or registers.
1677 * The "catch syscall" command now works on s390*-linux* targets.
1679 * The "compare-sections" command is no longer specific to target
1680 remote. It now works with all targets.
1682 * All native targets are now consistently called "native".
1683 Consequently, the "target child", "target GNU", "target djgpp",
1684 "target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"
1685 commands have been replaced with "target native". The QNX/NTO port
1686 leaves the "procfs" target in place and adds a "native" target for
1687 consistency with other ports. The impact on users should be minimal
1688 as these commands previously either throwed an error, or were
1689 no-ops. The target's name is visible in the output of the following
1690 commands: "help target", "info target", "info files", "maint print
1693 * The "target native" command now connects to the native target. This
1694 can be used to launch native programs even when "set
1695 auto-connect-native-target" is set to off.
1697 * GDB now supports access to Intel MPX registers on GNU/Linux.
1699 * Support for Intel AVX-512 registers on GNU/Linux.
1700 Support displaying and modifying Intel AVX-512 registers
1701 $zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
1703 * New remote packets
1705 qXfer:btrace:read's annex
1706 The qXfer:btrace:read packet supports a new annex 'delta' to read
1707 branch trace incrementally.
1711 ** Valid Python operations on gdb.Value objects representing
1712 structs/classes invoke the corresponding overloaded operators if
1714 ** New `Xmethods' feature in the Python API. Xmethods are
1715 additional methods or replacements for existing methods of a C++
1716 class. This feature is useful for those cases where a method
1717 defined in C++ source code could be inlined or optimized out by
1718 the compiler, making it unavailable to GDB.
1721 PowerPC64 GNU/Linux little-endian powerpc64le-*-linux*
1723 * The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"
1724 and "assf"), have been deprecated. Use the "sharedlibrary" command, or
1725 its alias "share", instead.
1727 * The commands "set remotebaud" and "show remotebaud" are no longer
1728 supported. Use "set serial baud" and "show serial baud" (respectively)
1733 ** A new option "-gdb-set mi-async" replaces "-gdb-set
1734 target-async". The latter is left as a deprecated alias of the
1735 former for backward compatibility. If the target supports it,
1736 CLI background execution commands are now always possible by
1737 default, independently of whether the frontend stated a
1738 preference for asynchronous execution with "-gdb-set mi-async".
1739 Previously "-gdb-set target-async off" affected both MI execution
1740 commands and CLI execution commands.
1742 *** Changes in GDB 7.7
1744 * Improved support for process record-replay and reverse debugging on
1745 arm*-linux* targets. Support for thumb32 and syscall instruction
1746 recording has been added.
1748 * GDB now supports SystemTap SDT probes on AArch64 GNU/Linux.
1750 * GDB now supports Fission DWP file format version 2.
1751 http://gcc.gnu.org/wiki/DebugFission
1753 * New convenience function "$_isvoid", to check whether an expression
1754 is void. A void expression is an expression where the type of the
1755 result is "void". For example, some convenience variables may be
1756 "void" when evaluated (e.g., "$_exitcode" before the execution of
1757 the program being debugged; or an undefined convenience variable).
1758 Another example, when calling a function whose return type is
1761 * The "maintenance print objfiles" command now takes an optional regexp.
1763 * The "catch syscall" command now works on arm*-linux* targets.
1765 * GDB now consistently shows "<not saved>" when printing values of
1766 registers the debug info indicates have not been saved in the frame
1767 and there's nowhere to retrieve them from
1768 (callee-saved/call-clobbered registers):
1773 (gdb) info registers rax
1776 Before, the former would print "<optimized out>", and the latter
1777 "*value not available*".
1779 * New script contrib/gdb-add-index.sh for adding .gdb_index sections
1784 ** Frame filters and frame decorators have been added.
1785 ** Temporary breakpoints are now supported.
1786 ** Line tables representation has been added.
1787 ** New attribute 'parent_type' for gdb.Field objects.
1788 ** gdb.Field objects can be used as subscripts on gdb.Value objects.
1789 ** New attribute 'name' for gdb.Type objects.
1793 Nios II ELF nios2*-*-elf
1794 Nios II GNU/Linux nios2*-*-linux
1795 Texas Instruments MSP430 msp430*-*-elf
1797 * Removed native configurations
1799 Support for these a.out NetBSD and OpenBSD obsolete configurations has
1800 been removed. ELF variants of these configurations are kept supported.
1802 arm*-*-netbsd* but arm*-*-netbsdelf* is kept supported.
1803 i[34567]86-*-netbsd* but i[34567]86-*-netbsdelf* is kept supported.
1804 i[34567]86-*-openbsd[0-2].* but i[34567]86-*-openbsd* is kept supported.
1805 i[34567]86-*-openbsd3.[0-3]
1806 m68*-*-netbsd* but m68*-*-netbsdelf* is kept supported.
1807 sparc-*-netbsd* but sparc-*-netbsdelf* is kept supported.
1808 vax-*-netbsd* but vax-*-netbsdelf* is kept supported.
1812 Like "catch throw", but catches a re-thrown exception.
1813 maint check-psymtabs
1814 Renamed from old "maint check-symtabs".
1816 Perform consistency checks on symtabs.
1817 maint expand-symtabs
1818 Expand symtabs matching an optional regexp.
1821 Display the details of GDB configure-time options.
1823 maint set|show per-command
1824 maint set|show per-command space
1825 maint set|show per-command time
1826 maint set|show per-command symtab
1827 Enable display of per-command gdb resource usage.
1829 remove-symbol-file FILENAME
1830 remove-symbol-file -a ADDRESS
1831 Remove a symbol file added via add-symbol-file. The file to remove
1832 can be identified by its filename or by an address that lies within
1833 the boundaries of this symbol file in memory.
1836 info exceptions REGEXP
1837 Display the list of Ada exceptions defined in the program being
1838 debugged. If provided, only the exceptions whose names match REGEXP
1843 set debug symfile off|on
1845 Control display of debugging info regarding reading symbol files and
1846 symbol tables within those files
1848 set print raw frame-arguments
1849 show print raw frame-arguments
1850 Set/show whether to print frame arguments in raw mode,
1851 disregarding any defined pretty-printers.
1853 set remote trace-status-packet
1854 show remote trace-status-packet
1855 Set/show the use of remote protocol qTStatus packet.
1859 Control display of debugging messages related to Nios II targets.
1863 Control whether target-assisted range stepping is enabled.
1865 set startup-with-shell
1866 show startup-with-shell
1867 Specifies whether Unix child processes are started via a shell or
1872 Use the target memory cache for accesses to the code segment. This
1873 improves performance of remote debugging (particularly disassembly).
1875 * You can now use a literal value 'unlimited' for options that
1876 interpret 0 or -1 as meaning "unlimited". E.g., "set
1877 trace-buffer-size unlimited" is now an alias for "set
1878 trace-buffer-size -1" and "set height unlimited" is now an alias for
1881 * The "set debug symtab-create" debugging option of GDB has been changed to
1882 accept a verbosity level. 0 means "off", 1 provides basic debugging
1883 output, and values of 2 or greater provides more verbose output.
1885 * New command-line options
1887 Display the details of GDB configure-time options.
1889 * The command 'tsave' can now support new option '-ctf' to save trace
1890 buffer in Common Trace Format.
1892 * Newly installed $prefix/bin/gcore acts as a shell interface for the
1895 * GDB now implements the the C++ 'typeid' operator.
1897 * The new convenience variable $_exception holds the exception being
1898 thrown or caught at an exception-related catchpoint.
1900 * The exception-related catchpoints, like "catch throw", now accept a
1901 regular expression which can be used to filter exceptions by type.
1903 * The new convenience variable $_exitsignal is automatically set to
1904 the terminating signal number when the program being debugged dies
1905 due to an uncaught signal.
1909 ** All MI commands now accept an optional "--language" option.
1910 Support for this feature can be verified by using the "-list-features"
1911 command, which should contain "language-option".
1913 ** The new command -info-gdb-mi-command allows the user to determine
1914 whether a GDB/MI command is supported or not.
1916 ** The "^error" result record returned when trying to execute an undefined
1917 GDB/MI command now provides a variable named "code" whose content is the
1918 "undefined-command" error code. Support for this feature can be verified
1919 by using the "-list-features" command, which should contain
1920 "undefined-command-error-code".
1922 ** The -trace-save MI command can optionally save trace buffer in Common
1925 ** The new command -dprintf-insert sets a dynamic printf breakpoint.
1927 ** The command -data-list-register-values now accepts an optional
1928 "--skip-unavailable" option. When used, only the available registers
1931 ** The new command -trace-frame-collected dumps collected variables,
1932 computed expressions, tvars, memory and registers in a traceframe.
1934 ** The commands -stack-list-locals, -stack-list-arguments and
1935 -stack-list-variables now accept an option "--skip-unavailable".
1936 When used, only the available locals or arguments are displayed.
1938 ** The -exec-run command now accepts an optional "--start" option.
1939 When used, the command follows the same semantics as the "start"
1940 command, stopping the program's execution at the start of its
1941 main subprogram. Support for this feature can be verified using
1942 the "-list-features" command, which should contain
1943 "exec-run-start-option".
1945 ** The new commands -catch-assert and -catch-exceptions insert
1946 catchpoints stopping the program when Ada exceptions are raised.
1948 ** The new command -info-ada-exceptions provides the equivalent of
1949 the new "info exceptions" command.
1951 * New system-wide configuration scripts
1952 A GDB installation now provides scripts suitable for use as system-wide
1953 configuration scripts for the following systems:
1957 * GDB now supports target-assigned range stepping with remote targets.
1958 This improves the performance of stepping source lines by reducing
1959 the number of control packets from/to GDB. See "New remote packets"
1962 * GDB now understands the element 'tvar' in the XML traceframe info.
1963 It has the id of the collected trace state variables.
1965 * On S/390 targets that provide the transactional-execution feature,
1966 the program interruption transaction diagnostic block (TDB) is now
1967 represented as a number of additional "registers" in GDB.
1969 * New remote packets
1973 The vCont packet supports a new 'r' action, that tells the remote
1974 stub to step through an address range itself, without GDB
1975 involvemement at each single-step.
1977 qXfer:libraries-svr4:read's annex
1978 The previously unused annex of the qXfer:libraries-svr4:read packet
1979 is now used to support passing an argument list. The remote stub
1980 reports support for this argument list to GDB's qSupported query.
1981 The defined arguments are "start" and "prev", used to reduce work
1982 necessary for library list updating, resulting in significant
1985 * New features in the GDB remote stub, GDBserver
1987 ** GDBserver now supports target-assisted range stepping. Currently
1988 enabled on x86/x86_64 GNU/Linux targets.
1990 ** GDBserver now adds element 'tvar' in the XML in the reply to
1991 'qXfer:traceframe-info:read'. It has the id of the collected
1992 trace state variables.
1994 ** GDBserver now supports hardware watchpoints on the MIPS GNU/Linux
1997 * New 'z' formatter for printing and examining memory, this displays the
1998 value as hexadecimal zero padded on the left to the size of the type.
2000 * GDB can now use Windows x64 unwinding data.
2002 * The "set remotebaud" command has been replaced by "set serial baud".
2003 Similarly, "show remotebaud" has been replaced by "show serial baud".
2004 The "set remotebaud" and "show remotebaud" commands are still available
2005 to provide backward compatibility with older versions of GDB.
2007 *** Changes in GDB 7.6
2009 * Target record has been renamed to record-full.
2010 Record/replay is now enabled with the "record full" command.
2011 This also affects settings that are associated with full record/replay
2012 that have been moved from "set/show record" to "set/show record full":
2014 set|show record full insn-number-max
2015 set|show record full stop-at-limit
2016 set|show record full memory-query
2018 * A new record target "record-btrace" has been added. The new target
2019 uses hardware support to record the control-flow of a process. It
2020 does not support replaying the execution, but it implements the
2021 below new commands for investigating the recorded execution log.
2022 This new recording method can be enabled using:
2026 The "record-btrace" target is only available on Intel Atom processors
2027 and requires a Linux kernel 2.6.32 or later.
2029 * Two new commands have been added for record/replay to give information
2030 about the recorded execution without having to replay the execution.
2031 The commands are only supported by "record btrace".
2033 record instruction-history prints the execution history at
2034 instruction granularity
2036 record function-call-history prints the execution history at
2037 function granularity
2039 * New native configurations
2041 ARM AArch64 GNU/Linux aarch64*-*-linux-gnu
2042 FreeBSD/powerpc powerpc*-*-freebsd
2043 x86_64/Cygwin x86_64-*-cygwin*
2044 Tilera TILE-Gx GNU/Linux tilegx*-*-linux-gnu
2048 ARM AArch64 aarch64*-*-elf
2049 ARM AArch64 GNU/Linux aarch64*-*-linux
2050 Lynx 178 PowerPC powerpc-*-lynx*178
2051 x86_64/Cygwin x86_64-*-cygwin*
2052 Tilera TILE-Gx GNU/Linux tilegx*-*-linux
2054 * If the configured location of system.gdbinit file (as given by the
2055 --with-system-gdbinit option at configure time) is in the
2056 data-directory (as specified by --with-gdb-datadir at configure
2057 time) or in one of its subdirectories, then GDB will look for the
2058 system-wide init file in the directory specified by the
2059 --data-directory command-line option.
2061 * New command line options:
2063 -nh Disables auto-loading of ~/.gdbinit, but still executes all the
2064 other initialization files, unlike -nx which disables all of them.
2066 * Removed command line options
2068 -epoch This was used by the gdb mode in Epoch, an ancient fork of
2071 * The 'ptype' and 'whatis' commands now accept an argument to control
2074 * 'info proc' now works on some core files.
2078 ** Vectors can be created with gdb.Type.vector.
2080 ** Python's atexit.register now works in GDB.
2082 ** Types can be pretty-printed via a Python API.
2084 ** Python 3 is now supported (in addition to Python 2.4 or later)
2086 ** New class gdb.Architecture exposes GDB's internal representation
2087 of architecture in the Python API.
2089 ** New method Frame.architecture returns the gdb.Architecture object
2090 corresponding to the frame's architecture.
2092 * New Python-based convenience functions:
2094 ** $_memeq(buf1, buf2, length)
2095 ** $_streq(str1, str2)
2097 ** $_regex(str, regex)
2099 * The 'cd' command now defaults to using '~' (the home directory) if not
2102 * The C++ ABI now defaults to the GNU v3 ABI. This has been the
2103 default for GCC since November 2000.
2105 * The command 'forward-search' can now be abbreviated as 'fo'.
2107 * The command 'info tracepoints' can now display 'installed on target'
2108 or 'not installed on target' for each non-pending location of tracepoint.
2110 * New configure options
2112 --enable-libmcheck/--disable-libmcheck
2113 By default, development versions are built with -lmcheck on hosts
2114 that support it, in order to help track memory corruption issues.
2115 Release versions, on the other hand, are built without -lmcheck
2116 by default. The --enable-libmcheck/--disable-libmcheck configure
2117 options allow the user to override that default.
2118 --with-babeltrace/--with-babeltrace-include/--with-babeltrace-lib
2119 This configure option allows the user to build GDB with
2120 libbabeltrace using which GDB can read Common Trace Format data.
2122 * New commands (for set/show, see "New options" below)
2125 Catch signals. This is similar to "handle", but allows commands and
2126 conditions to be attached.
2129 List the BFDs known to GDB.
2131 python-interactive [command]
2133 Start a Python interactive prompt, or evaluate the optional command
2134 and print the result of expressions.
2137 "py" is a new alias for "python".
2139 enable type-printer [name]...
2140 disable type-printer [name]...
2141 Enable or disable type printers.
2145 ** For the Renesas Super-H architecture, the "regs" command has been removed
2146 (has been deprecated in GDB 7.5), and "info all-registers" should be used
2151 set print type methods (on|off)
2152 show print type methods
2153 Control whether method declarations are displayed by "ptype".
2154 The default is to show them.
2156 set print type typedefs (on|off)
2157 show print type typedefs
2158 Control whether typedef definitions are displayed by "ptype".
2159 The default is to show them.
2161 set filename-display basename|relative|absolute
2162 show filename-display
2163 Control the way in which filenames is displayed.
2164 The default is "relative", which preserves previous behavior.
2166 set trace-buffer-size
2167 show trace-buffer-size
2168 Request target to change the size of trace buffer.
2170 set remote trace-buffer-size-packet auto|on|off
2171 show remote trace-buffer-size-packet
2172 Control the use of the remote protocol `QTBuffer:size' packet.
2176 Control display of debugging messages related to ARM AArch64.
2179 set debug coff-pe-read
2180 show debug coff-pe-read
2181 Control display of debugging messages related to reading of COFF/PE
2186 Control display of debugging messages related to Mach-O symbols
2189 set debug notification
2190 show debug notification
2191 Control display of debugging info for async remote notification.
2195 ** Command parameter changes are now notified using new async record
2196 "=cmd-param-changed".
2197 ** Trace frame changes caused by command "tfind" are now notified using
2198 new async record "=traceframe-changed".
2199 ** The creation, deletion and modification of trace state variables
2200 are now notified using new async records "=tsv-created",
2201 "=tsv-deleted" and "=tsv-modified".
2202 ** The start and stop of process record are now notified using new
2203 async record "=record-started" and "=record-stopped".
2204 ** Memory changes are now notified using new async record
2206 ** The data-disassemble command response will include a "fullname" field
2207 containing the absolute file name when source has been requested.
2208 ** New optional parameter COUNT added to the "-data-write-memory-bytes"
2209 command, to allow pattern filling of memory areas.
2210 ** New commands "-catch-load"/"-catch-unload" added for intercepting
2211 library load/unload events.
2212 ** The response to breakpoint commands and breakpoint async records
2213 includes an "installed" field containing a boolean state about each
2214 non-pending tracepoint location is whether installed on target or not.
2215 ** Output of the "-trace-status" command includes a "trace-file" field
2216 containing the name of the trace file being examined. This field is
2217 optional, and only present when examining a trace file.
2218 ** The "fullname" field is now always present along with the "file" field,
2219 even if the file cannot be found by GDB.
2221 * GDB now supports the "mini debuginfo" section, .gnu_debugdata.
2222 You must have the LZMA library available when configuring GDB for this
2223 feature to be enabled. For more information, see:
2224 http://fedoraproject.org/wiki/Features/MiniDebugInfo
2226 * New remote packets
2229 Set the size of trace buffer. The remote stub reports support for this
2230 packet to gdb's qSupported query.
2233 Enable Branch Trace Store (BTS)-based branch tracing for the current
2234 thread. The remote stub reports support for this packet to gdb's
2238 Disable branch tracing for the current thread. The remote stub reports
2239 support for this packet to gdb's qSupported query.
2242 Read the traced branches for the current thread. The remote stub
2243 reports support for this packet to gdb's qSupported query.
2245 *** Changes in GDB 7.5
2247 * GDB now supports x32 ABI. Visit <http://sites.google.com/site/x32abi/>
2248 for more x32 ABI info.
2250 * GDB now supports access to MIPS DSP registers on Linux targets.
2252 * GDB now supports debugging microMIPS binaries.
2254 * The "info os" command on GNU/Linux can now display information on
2255 several new classes of objects managed by the operating system:
2256 "info os procgroups" lists process groups
2257 "info os files" lists file descriptors
2258 "info os sockets" lists internet-domain sockets
2259 "info os shm" lists shared-memory regions
2260 "info os semaphores" lists semaphores
2261 "info os msg" lists message queues
2262 "info os modules" lists loaded kernel modules
2264 * GDB now has support for SDT (Static Defined Tracing) probes. Currently,
2265 the only implemented backend is for SystemTap probes (<sys/sdt.h>). You
2266 can set a breakpoint using the new "-probe, "-pstap" or "-probe-stap"
2267 options and inspect the probe arguments using the new $_probe_arg family
2268 of convenience variables. You can obtain more information about SystemTap
2269 in <http://sourceware.org/systemtap/>.
2271 * GDB now supports reversible debugging on ARM, it allows you to
2272 debug basic ARM and THUMB instructions, and provides
2273 record/replay support.
2275 * The option "symbol-reloading" has been deleted as it is no longer used.
2279 ** GDB commands implemented in Python can now be put in command class
2282 ** The "maint set python print-stack on|off" is now deleted.
2284 ** A new class, gdb.printing.FlagEnumerationPrinter, can be used to
2285 apply "flag enum"-style pretty-printing to any enum.
2287 ** gdb.lookup_symbol can now work when there is no current frame.
2289 ** gdb.Symbol now has a 'line' attribute, holding the line number in
2290 the source at which the symbol was defined.
2292 ** gdb.Symbol now has the new attribute 'needs_frame' and the new
2293 method 'value'. The former indicates whether the symbol needs a
2294 frame in order to compute its value, and the latter computes the
2297 ** A new method 'referenced_value' on gdb.Value objects which can
2298 dereference pointer as well as C++ reference values.
2300 ** New methods 'global_block' and 'static_block' on gdb.Symtab objects
2301 which return the global and static blocks (as gdb.Block objects),
2302 of the underlying symbol table, respectively.
2304 ** New function gdb.find_pc_line which returns the gdb.Symtab_and_line
2305 object associated with a PC value.
2307 ** gdb.Symtab_and_line has new attribute 'last' which holds the end
2308 of the address range occupied by code for the current source line.
2310 * Go language support.
2311 GDB now supports debugging programs written in the Go programming
2314 * GDBserver now supports stdio connections.
2315 E.g. (gdb) target remote | ssh myhost gdbserver - hello
2317 * The binary "gdbtui" can no longer be built or installed.
2318 Use "gdb -tui" instead.
2320 * GDB will now print "flag" enums specially. A flag enum is one where
2321 all the enumerator values have no bits in common when pairwise
2322 "and"ed. When printing a value whose type is a flag enum, GDB will
2323 show all the constants, e.g., for enum E { ONE = 1, TWO = 2}:
2324 (gdb) print (enum E) 3
2327 * The filename part of a linespec will now match trailing components
2328 of a source file name. For example, "break gcc/expr.c:1000" will
2329 now set a breakpoint in build/gcc/expr.c, but not
2330 build/libcpp/expr.c.
2332 * The "info proc" and "generate-core-file" commands will now also
2333 work on remote targets connected to GDBserver on Linux.
2335 * The command "info catch" has been removed. It has been disabled
2336 since December 2007.
2338 * The "catch exception" and "catch assert" commands now accept
2339 a condition at the end of the command, much like the "break"
2340 command does. For instance:
2342 (gdb) catch exception Constraint_Error if Barrier = True
2344 Previously, it was possible to add a condition to such catchpoints,
2345 but it had to be done as a second step, after the catchpoint had been
2346 created, using the "condition" command.
2348 * The "info static-tracepoint-marker" command will now also work on
2349 native Linux targets with in-process agent.
2351 * GDB can now set breakpoints on inlined functions.
2353 * The .gdb_index section has been updated to include symbols for
2354 inlined functions. GDB will ignore older .gdb_index sections by
2355 default, which could cause symbol files to be loaded more slowly
2356 until their .gdb_index sections can be recreated. The new command
2357 "set use-deprecated-index-sections on" will cause GDB to use any older
2358 .gdb_index sections it finds. This will restore performance, but the
2359 ability to set breakpoints on inlined functions will be lost in symbol
2360 files with older .gdb_index sections.
2362 The .gdb_index section has also been updated to record more information
2363 about each symbol. This speeds up the "info variables", "info functions"
2364 and "info types" commands when used with programs having the .gdb_index
2365 section, as well as speeding up debugging with shared libraries using
2366 the .gdb_index section.
2368 * Ada support for GDB/MI Variable Objects has been added.
2370 * GDB can now support 'breakpoint always-inserted mode' in 'record'
2375 ** New command -info-os is the MI equivalent of "info os".
2377 ** Output logs ("set logging" and related) now include MI output.
2381 ** "set use-deprecated-index-sections on|off"
2382 "show use-deprecated-index-sections on|off"
2383 Controls the use of deprecated .gdb_index sections.
2385 ** "catch load" and "catch unload" can be used to stop when a shared
2386 library is loaded or unloaded, respectively.
2388 ** "enable count" can be used to auto-disable a breakpoint after
2391 ** "info vtbl" can be used to show the virtual method tables for
2392 C++ and Java objects.
2394 ** "explore" and its sub commands "explore value" and "explore type"
2395 can be used to recursively explore values and types of
2396 expressions. These commands are available only if GDB is
2397 configured with '--with-python'.
2399 ** "info auto-load" shows status of all kinds of auto-loaded files,
2400 "info auto-load gdb-scripts" shows status of auto-loading GDB canned
2401 sequences of commands files, "info auto-load python-scripts"
2402 shows status of auto-loading Python script files,
2403 "info auto-load local-gdbinit" shows status of loading init file
2404 (.gdbinit) from current directory and "info auto-load libthread-db" shows
2405 status of inferior specific thread debugging shared library loading.
2407 ** "info auto-load-scripts", "set auto-load-scripts on|off"
2408 and "show auto-load-scripts" commands have been deprecated, use their
2409 "info auto-load python-scripts", "set auto-load python-scripts on|off"
2410 and "show auto-load python-scripts" counterparts instead.
2412 ** "dprintf location,format,args..." creates a dynamic printf, which
2413 is basically a breakpoint that does a printf and immediately
2414 resumes your program's execution, so it is like a printf that you
2415 can insert dynamically at runtime instead of at compiletime.
2417 ** "set print symbol"
2419 Controls whether GDB attempts to display the symbol, if any,
2420 corresponding to addresses it prints. This defaults to "on", but
2421 you can set it to "off" to restore GDB's previous behavior.
2423 * Deprecated commands
2425 ** For the Renesas Super-H architecture, the "regs" command has been
2426 deprecated, and "info all-registers" should be used instead.
2430 Renesas RL78 rl78-*-elf
2431 HP OpenVMS ia64 ia64-hp-openvms*
2433 * GDBserver supports evaluation of breakpoint conditions. When
2434 support is advertised by GDBserver, GDB may be told to send the
2435 breakpoint conditions in bytecode form to GDBserver. GDBserver
2436 will only report the breakpoint trigger to GDB when its condition
2441 set mips compression
2442 show mips compression
2443 Select the compressed ISA encoding used in functions that have no symbol
2444 information available. The encoding can be set to either of:
2447 and is updated automatically from ELF file flags if available.
2449 set breakpoint condition-evaluation
2450 show breakpoint condition-evaluation
2451 Control whether breakpoint conditions are evaluated by GDB ("host") or by
2452 GDBserver ("target"). Default option "auto" chooses the most efficient
2454 This option can improve debugger efficiency depending on the speed of the
2458 Disable auto-loading globally.
2461 Show auto-loading setting of all kinds of auto-loaded files.
2463 set auto-load gdb-scripts on|off
2464 show auto-load gdb-scripts
2465 Control auto-loading of GDB canned sequences of commands files.
2467 set auto-load python-scripts on|off
2468 show auto-load python-scripts
2469 Control auto-loading of Python script files.
2471 set auto-load local-gdbinit on|off
2472 show auto-load local-gdbinit
2473 Control loading of init file (.gdbinit) from current directory.
2475 set auto-load libthread-db on|off
2476 show auto-load libthread-db
2477 Control auto-loading of inferior specific thread debugging shared library.
2479 set auto-load scripts-directory <dir1>[:<dir2>...]
2480 show auto-load scripts-directory
2481 Set a list of directories from which to load auto-loaded scripts.
2482 Automatically loaded Python scripts and GDB scripts are located in one
2483 of the directories listed by this option.
2484 The delimiter (':' above) may differ according to the host platform.
2486 set auto-load safe-path <dir1>[:<dir2>...]
2487 show auto-load safe-path
2488 Set a list of directories from which it is safe to auto-load files.
2489 The delimiter (':' above) may differ according to the host platform.
2491 set debug auto-load on|off
2492 show debug auto-load
2493 Control display of debugging info for auto-loading the files above.
2495 set dprintf-style gdb|call|agent
2497 Control the way in which a dynamic printf is performed; "gdb"
2498 requests a GDB printf command, while "call" causes dprintf to call a
2499 function in the inferior. "agent" requests that the target agent
2500 (such as GDBserver) do the printing.
2502 set dprintf-function <expr>
2503 show dprintf-function
2504 set dprintf-channel <expr>
2505 show dprintf-channel
2506 Set the function and optional first argument to the call when using
2507 the "call" style of dynamic printf.
2509 set disconnected-dprintf on|off
2510 show disconnected-dprintf
2511 Control whether agent-style dynamic printfs continue to be in effect
2512 after GDB disconnects.
2514 * New configure options
2516 --with-auto-load-dir
2517 Configure default value for the 'set auto-load scripts-directory'
2518 setting above. It defaults to '$debugdir:$datadir/auto-load',
2519 $debugdir representing global debugging info directories (available
2520 via 'show debug-file-directory') and $datadir representing GDB's data
2521 directory (available via 'show data-directory').
2523 --with-auto-load-safe-path
2524 Configure default value for the 'set auto-load safe-path' setting
2525 above. It defaults to the --with-auto-load-dir setting.
2527 --without-auto-load-safe-path
2528 Set 'set auto-load safe-path' to '/', effectively disabling this
2531 * New remote packets
2533 z0/z1 conditional breakpoints extension
2535 The z0/z1 breakpoint insertion packets have been extended to carry
2536 a list of conditional expressions over to the remote stub depending on the
2537 condition evaluation mode. The use of this extension can be controlled
2538 via the "set remote conditional-breakpoints-packet" command.
2542 Specify the signals which the remote stub may pass to the debugged
2543 program without GDB involvement.
2545 * New command line options
2547 --init-command=FILE, -ix Like --command, -x but execute it
2548 before loading inferior.
2549 --init-eval-command=COMMAND, -iex Like --eval-command=COMMAND, -ex but
2550 execute it before loading inferior.
2552 *** Changes in GDB 7.4
2554 * GDB now handles ambiguous linespecs more consistently; the existing
2555 FILE:LINE support has been expanded to other types of linespecs. A
2556 breakpoint will now be set on all matching locations in all
2557 inferiors, and locations will be added or removed according to
2560 * GDB now allows you to skip uninteresting functions and files when
2561 stepping with the "skip function" and "skip file" commands.
2563 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
2564 and "show remote hardware-watchpoint-length-limit". These allows to
2565 set or show the maximum length limit (in bytes) of a remote
2566 target hardware watchpoint.
2568 This allows e.g. to use "unlimited" hardware watchpoints with the
2569 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
2570 watchpoints are slower than real hardware watchpoints but are
2571 significantly faster than gdb software watchpoints.
2575 ** The register_pretty_printer function in module gdb.printing now takes
2576 an optional `replace' argument. If True, the new printer replaces any
2579 ** The "maint set python print-stack on|off" command has been
2580 deprecated and will be deleted in GDB 7.5.
2581 A new command: "set python print-stack none|full|message" has
2582 replaced it. Additionally, the default for "print-stack" is
2583 now "message", which just prints the error message without
2586 ** A prompt substitution hook (prompt_hook) is now available to the
2589 ** A new Python module, gdb.prompt has been added to the GDB Python
2590 modules library. This module provides functionality for
2591 escape sequences in prompts (used by set/show
2592 extended-prompt). These escape sequences are replaced by their
2593 corresponding value.
2595 ** Python commands and convenience-functions located in
2596 'data-directory'/python/gdb/command and
2597 'data-directory'/python/gdb/function are now automatically loaded
2600 ** Blocks now provide four new attributes. global_block and
2601 static_block will return the global and static blocks
2602 respectively. is_static and is_global are boolean attributes
2603 that indicate if the block is one of those two types.
2605 ** Symbols now provide the "type" attribute, the type of the symbol.
2607 ** The "gdb.breakpoint" function has been deprecated in favor of
2610 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
2611 of a function. This class is based on the "finish" command
2612 available in the CLI.
2614 ** Type objects for struct and union types now allow access to
2615 the fields using standard Python dictionary (mapping) methods.
2616 For example, "some_type['myfield']" now works, as does
2617 "some_type.items()".
2619 ** A new event "gdb.new_objfile" has been added, triggered by loading a
2622 ** A new function, "deep_items" has been added to the gdb.types
2623 module in the GDB Python modules library. This function returns
2624 an iterator over the fields of a struct or union type. Unlike
2625 the standard Python "iteritems" method, it will recursively traverse
2626 any anonymous fields.
2630 ** "*stopped" events can report several new "reason"s, such as
2633 ** Breakpoint changes are now notified using new async records, like
2634 "=breakpoint-modified".
2636 ** New command -ada-task-info.
2638 * libthread-db-search-path now supports two special values: $sdir and $pdir.
2639 $sdir specifies the default system locations of shared libraries.
2640 $pdir specifies the directory where the libpthread used by the application
2643 GDB no longer looks in $sdir and $pdir after it has searched the directories
2644 mentioned in libthread-db-search-path. If you want to search those
2645 directories, they must be specified in libthread-db-search-path.
2646 The default value of libthread-db-search-path on GNU/Linux and Solaris
2647 systems is now "$sdir:$pdir".
2649 $pdir is not supported by gdbserver, it is currently ignored.
2650 $sdir is supported by gdbserver.
2652 * New configure option --with-iconv-bin.
2653 When using the internationalization support like the one in the GNU C
2654 library, GDB will invoke the "iconv" program to get a list of supported
2655 character sets. If this program lives in a non-standard location, one can
2656 use this option to specify where to find it.
2658 * When natively debugging programs on PowerPC BookE processors running
2659 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
2660 watchpoints, which specify a mask in addition to an address to watch.
2661 The mask specifies that some bits of an address (the bits which are
2662 reset in the mask) should be ignored when matching the address accessed
2663 by the inferior against the watchpoint address. See the "PowerPC Embedded"
2664 section in the user manual for more details.
2666 * The new option --once causes GDBserver to stop listening for connections once
2667 the first connection is made. The listening port used by GDBserver will
2668 become available after that.
2670 * New commands "info macros" and "alias" have been added.
2672 * New function parameters suffix @entry specifies value of function parameter
2673 at the time the function got called. Entry values are available only since
2679 "!" is now an alias of the "shell" command.
2680 Note that no space is needed between "!" and SHELL COMMAND.
2684 watch EXPRESSION mask MASK_VALUE
2685 The watch command now supports the mask argument which allows creation
2686 of masked watchpoints, if the current architecture supports this feature.
2688 info auto-load-scripts [REGEXP]
2689 This command was formerly named "maintenance print section-scripts".
2690 It is now generally useful and is no longer a maintenance-only command.
2692 info macro [-all] [--] MACRO
2693 The info macro command has new options `-all' and `--'. The first for
2694 printing all definitions of a macro. The second for explicitly specifying
2695 the end of arguments and the beginning of the macro name in case the macro
2696 name starts with a hyphen.
2698 collect[/s] EXPRESSIONS
2699 The tracepoint collect command now takes an optional modifier "/s"
2700 that directs it to dereference pointer-to-character types and
2701 collect the bytes of memory up to a zero byte. The behavior is
2702 similar to what you see when you use the regular print command on a
2703 string. An optional integer following the "/s" sets a bound on the
2704 number of bytes that will be collected.
2707 The trace start command now interprets any supplied arguments as a
2708 note to be recorded with the trace run, with an effect similar to
2709 setting the variable trace-notes.
2712 The trace stop command now interprets any arguments as a note to be
2713 mentioned along with the tstatus report that the trace was stopped
2714 with a command. The effect is similar to setting the variable
2717 * Tracepoints can now be enabled and disabled at any time after a trace
2718 experiment has been started using the standard "enable" and "disable"
2719 commands. It is now possible to start a trace experiment with no enabled
2720 tracepoints; GDB will display a warning, but will allow the experiment to
2721 begin, assuming that tracepoints will be enabled as needed while the trace
2724 * Fast tracepoints on 32-bit x86-architectures can now be placed at
2725 locations with 4-byte instructions, when they were previously
2726 limited to locations with instructions of 5 bytes or longer.
2730 set debug dwarf2-read
2731 show debug dwarf2-read
2732 Turns on or off display of debugging messages related to reading
2733 DWARF debug info. The default is off.
2735 set debug symtab-create
2736 show debug symtab-create
2737 Turns on or off display of debugging messages related to symbol table
2738 creation. The default is off.
2741 show extended-prompt
2742 Set the GDB prompt, and allow escape sequences to be inserted to
2743 display miscellaneous information (see 'help set extended-prompt'
2744 for the list of sequences). This prompt (and any information
2745 accessed through the escape sequences) is updated every time the
2746 prompt is displayed.
2748 set print entry-values (both|compact|default|if-needed|no|only|preferred)
2749 show print entry-values
2750 Set printing of frame argument values at function entry. In some cases
2751 GDB can determine the value of function argument which was passed by the
2752 function caller, even if the value was modified inside the called function.
2754 set debug entry-values
2755 show debug entry-values
2756 Control display of debugging info for determining frame argument values at
2757 function entry and virtual tail call frames.
2759 set basenames-may-differ
2760 show basenames-may-differ
2761 Set whether a source file may have multiple base names.
2762 (A "base name" is the name of a file with the directory part removed.
2763 Example: The base name of "/home/user/hello.c" is "hello.c".)
2764 If set, GDB will canonicalize file names (e.g., expand symlinks)
2765 before comparing them. Canonicalization is an expensive operation,
2766 but it allows the same file be known by more than one base name.
2767 If not set (the default), all source files are assumed to have just
2768 one base name, and gdb will do file name comparisons more efficiently.
2774 Set a user name and notes for the current and any future trace runs.
2775 This is useful for long-running and/or disconnected traces, to
2776 inform others (or yourself) as to who is running the trace, supply
2777 contact information, or otherwise explain what is going on.
2779 set trace-stop-notes
2780 show trace-stop-notes
2781 Set a note attached to the trace run, that is displayed when the
2782 trace has been stopped by a tstop command. This is useful for
2783 instance as an explanation, if you are stopping a trace run that was
2784 started by someone else.
2786 * New remote packets
2790 Dynamically enable a tracepoint in a started trace experiment.
2794 Dynamically disable a tracepoint in a started trace experiment.
2798 Set the user and notes of the trace run.
2802 Query the current status of a tracepoint.
2806 Query the minimum length of instruction at which a fast tracepoint may
2809 * Dcache size (number of lines) and line-size are now runtime-configurable
2810 via "set dcache line" and "set dcache line-size" commands.
2814 Texas Instruments TMS320C6x tic6x-*-*
2818 Renesas RL78 rl78-*-elf
2820 *** Changes in GDB 7.3.1
2822 * The build failure for NetBSD and OpenBSD targets have now been fixed.
2824 *** Changes in GDB 7.3
2826 * GDB has a new command: "thread find [REGEXP]".
2827 It finds the thread id whose name, target id, or thread extra info
2828 matches the given regular expression.
2830 * The "catch syscall" command now works on mips*-linux* targets.
2832 * The -data-disassemble MI command now supports modes 2 and 3 for
2833 dumping the instruction opcodes.
2835 * New command line options
2837 -data-directory DIR Specify DIR as the "data-directory".
2838 This is mostly for testing purposes.
2840 * The "maint set python auto-load on|off" command has been renamed to
2841 "set auto-load-scripts on|off".
2843 * GDB has a new command: "set directories".
2844 It is like the "dir" command except that it replaces the
2845 source path list instead of augmenting it.
2847 * GDB now understands thread names.
2849 On GNU/Linux, "info threads" will display the thread name as set by
2850 prctl or pthread_setname_np.
2852 There is also a new command, "thread name", which can be used to
2853 assign a name internally for GDB to display.
2856 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
2857 has been integrated into GDB.
2861 ** The function gdb.Write now accepts an optional keyword 'stream'.
2862 This keyword, when provided, will direct the output to either
2863 stdout, stderr, or GDB's logging output.
2865 ** Parameters can now be be sub-classed in Python, and in particular
2866 you may implement the get_set_doc and get_show_doc functions.
2867 This improves how Parameter set/show documentation is processed
2868 and allows for more dynamic content.
2870 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
2871 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
2872 have an is_valid method.
2874 ** Breakpoints can now be sub-classed in Python, and in particular
2875 you may implement a 'stop' function that is executed each time
2876 the inferior reaches that breakpoint.
2878 ** New function gdb.lookup_global_symbol looks up a global symbol.
2880 ** GDB values in Python are now callable if the value represents a
2881 function. For example, if 'some_value' represents a function that
2882 takes two integer parameters and returns a value, you can call
2883 that function like so:
2885 result = some_value (10,20)
2887 ** Module gdb.types has been added.
2888 It contains a collection of utilities for working with gdb.Types objects:
2889 get_basic_type, has_field, make_enum_dict.
2891 ** Module gdb.printing has been added.
2892 It contains utilities for writing and registering pretty-printers.
2893 New classes: PrettyPrinter, SubPrettyPrinter,
2894 RegexpCollectionPrettyPrinter.
2895 New function: register_pretty_printer.
2897 ** New commands "info pretty-printers", "enable pretty-printer" and
2898 "disable pretty-printer" have been added.
2900 ** gdb.parameter("directories") is now available.
2902 ** New function gdb.newest_frame returns the newest frame in the
2905 ** The gdb.InferiorThread class has a new "name" attribute. This
2906 holds the thread's name.
2908 ** Python Support for Inferior events.
2909 Python scripts can add observers to be notified of events
2910 occurring in the process being debugged.
2911 The following events are currently supported:
2912 - gdb.events.cont Continue event.
2913 - gdb.events.exited Inferior exited event.
2914 - gdb.events.stop Signal received, and Breakpoint hit events.
2918 ** GDB now puts template parameters in scope when debugging in an
2919 instantiation. For example, if you have:
2921 template<int X> int func (void) { return X; }
2923 then if you step into func<5>, "print X" will show "5". This
2924 feature requires proper debuginfo support from the compiler; it
2925 was added to GCC 4.5.
2927 ** The motion commands "next", "finish", "until", and "advance" now
2928 work better when exceptions are thrown. In particular, GDB will
2929 no longer lose control of the inferior; instead, the GDB will
2930 stop the inferior at the point at which the exception is caught.
2931 This functionality requires a change in the exception handling
2932 code that was introduced in GCC 4.5.
2934 * GDB now follows GCC's rules on accessing volatile objects when
2935 reading or writing target state during expression evaluation.
2936 One notable difference to prior behavior is that "print x = 0"
2937 no longer generates a read of x; the value of the assignment is
2938 now always taken directly from the value being assigned.
2940 * GDB now has some support for using labels in the program's source in
2941 linespecs. For instance, you can use "advance label" to continue
2942 execution to a label.
2944 * GDB now has support for reading and writing a new .gdb_index
2945 section. This section holds a fast index of DWARF debugging
2946 information and can be used to greatly speed up GDB startup and
2947 operation. See the documentation for `save gdb-index' for details.
2949 * The "watch" command now accepts an optional "-location" argument.
2950 When used, this causes GDB to watch the memory referred to by the
2951 expression. Such a watchpoint is never deleted due to it going out
2954 * GDB now supports thread debugging of core dumps on GNU/Linux.
2956 GDB now activates thread debugging using the libthread_db library
2957 when debugging GNU/Linux core dumps, similarly to when debugging
2958 live processes. As a result, when debugging a core dump file, GDB
2959 is now able to display pthread_t ids of threads. For example, "info
2960 threads" shows the same output as when debugging the process when it
2961 was live. In earlier releases, you'd see something like this:
2964 * 1 LWP 6780 main () at main.c:10
2966 While now you see this:
2969 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
2971 It is also now possible to inspect TLS variables when debugging core
2974 When debugging a core dump generated on a machine other than the one
2975 used to run GDB, you may need to point GDB at the correct
2976 libthread_db library with the "set libthread-db-search-path"
2977 command. See the user manual for more details on this command.
2979 * When natively debugging programs on PowerPC BookE processors running
2980 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
2981 which stop execution of the inferior whenever it executes an instruction
2982 at any address within the specified range. See the "PowerPC Embedded"
2983 section in the user manual for more details.
2985 * New features in the GDB remote stub, GDBserver
2987 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
2988 and i686 LynxOS (version 5.x).
2990 ** GDBserver is now supported on Blackfin Linux.
2992 * New native configurations
2994 ia64 HP-UX ia64-*-hpux*
2998 Analog Devices, Inc. Blackfin Processor bfin-*
3000 * Ada task switching is now supported on sparc-elf targets when
3001 debugging a program using the Ravenscar Profile. For more information,
3002 see the "Tasking Support when using the Ravenscar Profile" section
3003 in the GDB user manual.
3005 * Guile support was removed.
3007 * New features in the GNU simulator
3009 ** The --map-info flag lists all known core mappings.
3011 ** CFI flashes may be simulated via the "cfi" device.
3013 *** Changes in GDB 7.2
3015 * Shared library support for remote targets by default
3017 When GDB is configured for a generic, non-OS specific target, like
3018 for example, --target=arm-eabi or one of the many *-*-elf targets,
3019 GDB now queries remote stubs for loaded shared libraries using the
3020 `qXfer:libraries:read' packet. Previously, shared library support
3021 was always disabled for such configurations.
3025 ** Argument Dependent Lookup (ADL)
3027 In C++ ADL lookup directs function search to the namespaces of its
3028 arguments even if the namespace has not been imported.
3038 Here the compiler will search for `foo' in the namespace of 'b'
3039 and find A::foo. GDB now supports this. This construct is commonly
3040 used in the Standard Template Library for operators.
3042 ** Improved User Defined Operator Support
3044 In addition to member operators, GDB now supports lookup of operators
3045 defined in a namespace and imported with a `using' directive, operators
3046 defined in the global scope, operators imported implicitly from an
3047 anonymous namespace, and the ADL operators mentioned in the previous
3049 GDB now also supports proper overload resolution for all the previously
3050 mentioned flavors of operators.
3052 ** static const class members
3054 Printing of static const class members that are initialized in the
3055 class definition has been fixed.
3057 * Windows Thread Information Block access.
3059 On Windows targets, GDB now supports displaying the Windows Thread
3060 Information Block (TIB) structure. This structure is visible either
3061 by using the new command `info w32 thread-information-block' or, by
3062 dereferencing the new convenience variable named `$_tlb', a
3063 thread-specific pointer to the TIB. This feature is also supported
3064 when remote debugging using GDBserver.
3066 * Static tracepoints
3068 Static tracepoints are calls in the user program into a tracing
3069 library. One such library is a port of the LTTng kernel tracer to
3070 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
3071 When debugging with GDBserver, GDB now supports combining the GDB
3072 tracepoint machinery with such libraries. For example: the user can
3073 use GDB to probe a static tracepoint marker (a call from the user
3074 program into the tracing library) with the new "strace" command (see
3075 "New commands" below). This creates a "static tracepoint" in the
3076 breakpoint list, that can be manipulated with the same feature set
3077 as fast and regular tracepoints. E.g., collect registers, local and
3078 global variables, collect trace state variables, and define
3079 tracepoint conditions. In addition, the user can collect extra
3080 static tracepoint marker specific data, by collecting the new
3081 $_sdata internal variable. When analyzing the trace buffer, you can
3082 inspect $_sdata like any other variable available to GDB. For more
3083 information, see the "Tracepoints" chapter in GDB user manual. New
3084 remote packets have been defined to support static tracepoints, see
3085 the "New remote packets" section below.
3087 * Better reconstruction of tracepoints after disconnected tracing
3089 GDB will attempt to download the original source form of tracepoint
3090 definitions when starting a trace run, and then will upload these
3091 upon reconnection to the target, resulting in a more accurate
3092 reconstruction of the tracepoints that are in use on the target.
3096 You can now exercise direct control over the ways that GDB can
3097 affect your program. For instance, you can disallow the setting of
3098 breakpoints, so that the program can run continuously (assuming
3099 non-stop mode). In addition, the "observer" variable is available
3100 to switch all of the different controls; in observer mode, GDB
3101 cannot affect the target's behavior at all, which is useful for
3102 tasks like diagnosing live systems in the field.
3104 * The new convenience variable $_thread holds the number of the
3107 * New remote packets
3111 Return the address of the Windows Thread Information Block of a given thread.
3115 In response to several of the tracepoint packets, the target may now
3116 also respond with a number of intermediate `qRelocInsn' request
3117 packets before the final result packet, to have GDB handle
3118 relocating an instruction to execute at a different address. This
3119 is particularly useful for stubs that support fast tracepoints. GDB
3120 reports support for this feature in the qSupported packet.
3124 List static tracepoint markers in the target program.
3128 List static tracepoint markers at a given address in the target
3131 qXfer:statictrace:read
3133 Read the static trace data collected (by a `collect $_sdata'
3134 tracepoint action). The remote stub reports support for this packet
3135 to gdb's qSupported query.
3139 Send the current settings of GDB's permission flags.
3143 Send part of the source (textual) form of a tracepoint definition,
3144 which includes location, conditional, and action list.
3146 * The source command now accepts a -s option to force searching for the
3147 script in the source search path even if the script name specifies
3150 * New features in the GDB remote stub, GDBserver
3152 - GDBserver now support tracepoints (including fast tracepoints, and
3153 static tracepoints). The feature is currently supported by the
3154 i386-linux and amd64-linux builds. See the "Tracepoints support
3155 in gdbserver" section in the manual for more information.
3157 GDBserver JIT compiles the tracepoint's conditional agent
3158 expression bytecode into native code whenever possible for low
3159 overhead dynamic tracepoints conditionals. For such tracepoints,
3160 an expression that examines program state is evaluated when the
3161 tracepoint is reached, in order to determine whether to capture
3162 trace data. If the condition is simple and false, processing the
3163 tracepoint finishes very quickly and no data is gathered.
3165 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
3166 for static tracepoints support.
3168 - GDBserver now supports x86_64 Windows 64-bit debugging.
3170 * GDB now sends xmlRegisters= in qSupported packet to indicate that
3171 it understands register description.
3173 * The --batch flag now disables pagination and queries.
3175 * X86 general purpose registers
3177 GDB now supports reading/writing byte, word and double-word x86
3178 general purpose registers directly. This means you can use, say,
3179 $ah or $ax to refer, respectively, to the byte register AH and
3180 16-bit word register AX that are actually portions of the 32-bit
3181 register EAX or 64-bit register RAX.
3183 * The `commands' command now accepts a range of breakpoints to modify.
3184 A plain `commands' following a command that creates multiple
3185 breakpoints affects all the breakpoints set by that command. This
3186 applies to breakpoints set by `rbreak', and also applies when a
3187 single `break' command creates multiple breakpoints (e.g.,
3188 breakpoints on overloaded c++ functions).
3190 * The `rbreak' command now accepts a filename specification as part of
3191 its argument, limiting the functions selected by the regex to those
3192 in the specified file.
3194 * Support for remote debugging Windows and SymbianOS shared libraries
3195 from Unix hosts has been improved. Non Windows GDB builds now can
3196 understand target reported file names that follow MS-DOS based file
3197 system semantics, such as file names that include drive letters and
3198 use the backslash character as directory separator. This makes it
3199 possible to transparently use the "set sysroot" and "set
3200 solib-search-path" on Unix hosts to point as host copies of the
3201 target's shared libraries. See the new command "set
3202 target-file-system-kind" described below, and the "Commands to
3203 specify files" section in the user manual for more information.
3207 eval template, expressions...
3208 Convert the values of one or more expressions under the control
3209 of the string template to a command line, and call it.
3211 set target-file-system-kind unix|dos-based|auto
3212 show target-file-system-kind
3213 Set or show the assumed file system kind for target reported file
3216 save breakpoints <filename>
3217 Save all current breakpoint definitions to a file suitable for use
3218 in a later debugging session. To read the saved breakpoint
3219 definitions, use the `source' command.
3221 `save tracepoints' is a new alias for `save-tracepoints'. The latter
3224 info static-tracepoint-markers
3225 Display information about static tracepoint markers in the target.
3227 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
3228 Define a static tracepoint by probing a marker at the given
3229 function, line, address, or marker ID.
3233 Enable and disable observer mode.
3235 set may-write-registers on|off
3236 set may-write-memory on|off
3237 set may-insert-breakpoints on|off
3238 set may-insert-tracepoints on|off
3239 set may-insert-fast-tracepoints on|off
3240 set may-interrupt on|off
3241 Set individual permissions for GDB effects on the target. Note that
3242 some of these settings can have undesirable or surprising
3243 consequences, particularly when changed in the middle of a session.
3244 For instance, disabling the writing of memory can prevent
3245 breakpoints from being inserted, cause single-stepping to fail, or
3246 even crash your program, if you disable after breakpoints have been
3247 inserted. However, GDB should not crash.
3249 set record memory-query on|off
3250 show record memory-query
3251 Control whether to stop the inferior if memory changes caused
3252 by an instruction cannot be recorded.
3257 The disassemble command now supports "start,+length" form of two arguments.
3261 ** GDB now provides a new directory location, called the python directory,
3262 where Python scripts written for GDB can be installed. The location
3263 of that directory is <data-directory>/python, where <data-directory>
3264 is the GDB data directory. For more details, see section `Scripting
3265 GDB using Python' in the manual.
3267 ** The GDB Python API now has access to breakpoints, symbols, symbol
3268 tables, program spaces, inferiors, threads and frame's code blocks.
3269 Additionally, GDB Parameters can now be created from the API, and
3270 manipulated via set/show in the CLI.
3272 ** New functions gdb.target_charset, gdb.target_wide_charset,
3273 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
3275 ** New exception gdb.GdbError.
3277 ** Pretty-printers are now also looked up in the current program space.
3279 ** Pretty-printers can now be individually enabled and disabled.
3281 ** GDB now looks for names of Python scripts to auto-load in a
3282 special section named `.debug_gdb_scripts', in addition to looking
3283 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
3285 * Tracepoint actions were unified with breakpoint commands. In particular,
3286 there are no longer differences in "info break" output for breakpoints and
3287 tracepoints and the "commands" command can be used for both tracepoints and
3288 regular breakpoints.
3292 ARM Symbian arm*-*-symbianelf*
3294 * D language support.
3295 GDB now supports debugging programs written in the D programming
3298 * GDB now supports the extended ptrace interface for PowerPC which is
3299 available since Linux kernel version 2.6.34. This automatically enables
3300 any hardware breakpoints and additional hardware watchpoints available in
3301 the processor. The old ptrace interface exposes just one hardware
3302 watchpoint and no hardware breakpoints.
3304 * GDB is now able to use the Data Value Compare (DVC) register available on
3305 embedded PowerPC processors to implement in hardware simple watchpoint
3306 conditions of the form:
3308 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
3310 This works in native GDB running on Linux kernels with the extended ptrace
3311 interface mentioned above.
3313 *** Changes in GDB 7.1
3317 ** Namespace Support
3319 GDB now supports importing of namespaces in C++. This enables the
3320 user to inspect variables from imported namespaces. Support for
3321 namepace aliasing has also been added. So, if a namespace is
3322 aliased in the current scope (e.g. namepace C=A; ) the user can
3323 print variables using the alias (e.g. (gdb) print C::x).
3327 All known bugs relating to the printing of virtual base class were
3328 fixed. It is now possible to call overloaded static methods using a
3333 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
3334 and reinterpret_cast<> are now handled by the C++ expression parser.
3338 Xilinx MicroBlaze microblaze-*-*
3343 Xilinx MicroBlaze microblaze
3346 * Multi-program debugging.
3348 GDB now has support for multi-program (a.k.a. multi-executable or
3349 multi-exec) debugging. This allows for debugging multiple inferiors
3350 simultaneously each running a different program under the same GDB
3351 session. See "Debugging Multiple Inferiors and Programs" in the
3352 manual for more information. This implied some user visible changes
3353 in the multi-inferior support. For example, "info inferiors" now
3354 lists inferiors that are not running yet or that have exited
3355 already. See also "New commands" and "New options" below.
3357 * New tracing features
3359 GDB's tracepoint facility now includes several new features:
3361 ** Trace state variables
3363 GDB tracepoints now include support for trace state variables, which
3364 are variables managed by the target agent during a tracing
3365 experiment. They are useful for tracepoints that trigger each
3366 other, so for instance one tracepoint can count hits in a variable,
3367 and then a second tracepoint has a condition that is true when the
3368 count reaches a particular value. Trace state variables share the
3369 $-syntax of GDB convenience variables, and can appear in both
3370 tracepoint actions and condition expressions. Use the "tvariable"
3371 command to create, and "info tvariables" to view; see "Trace State
3372 Variables" in the manual for more detail.
3376 GDB now includes an option for defining fast tracepoints, which
3377 targets may implement more efficiently, such as by installing a jump
3378 into the target agent rather than a trap instruction. The resulting
3379 speedup can be by two orders of magnitude or more, although the
3380 tradeoff is that some program locations on some target architectures
3381 might not allow fast tracepoint installation, for instance if the
3382 instruction to be replaced is shorter than the jump. To request a
3383 fast tracepoint, use the "ftrace" command, with syntax identical to
3384 the regular trace command.
3386 ** Disconnected tracing
3388 It is now possible to detach GDB from the target while it is running
3389 a trace experiment, then reconnect later to see how the experiment
3390 is going. In addition, a new variable disconnected-tracing lets you
3391 tell the target agent whether to continue running a trace if the
3392 connection is lost unexpectedly.
3396 GDB now has the ability to save the trace buffer into a file, and
3397 then use that file as a target, similarly to you can do with
3398 corefiles. You can select trace frames, print data that was
3399 collected in them, and use tstatus to display the state of the
3400 tracing run at the moment that it was saved. To create a trace
3401 file, use "tsave <filename>", and to use it, do "target tfile
3404 ** Circular trace buffer
3406 You can ask the target agent to handle the trace buffer as a
3407 circular buffer, discarding the oldest trace frames to make room for
3408 newer ones, by setting circular-trace-buffer to on. This feature may
3409 not be available for all target agents.
3414 The disassemble command, when invoked with two arguments, now requires
3415 the arguments to be comma-separated.
3418 The info variables command now displays variable definitions. Files
3419 which only declare a variable are not shown.
3422 The source command is now capable of sourcing Python scripts.
3423 This feature is dependent on the debugger being build with Python
3426 Related to this enhancement is also the introduction of a new command
3427 "set script-extension" (see below).
3429 * New commands (for set/show, see "New options" below)
3431 record save [<FILENAME>]
3432 Save a file (in core file format) containing the process record
3433 execution log for replay debugging at a later time.
3435 record restore <FILENAME>
3436 Restore the process record execution log that was saved at an
3437 earlier time, for replay debugging.
3439 add-inferior [-copies <N>] [-exec <FILENAME>]
3442 clone-inferior [-copies <N>] [ID]
3443 Make a new inferior ready to execute the same program another
3444 inferior has loaded.
3449 maint info program-spaces
3450 List the program spaces loaded into GDB.
3452 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
3453 show remote interrupt-sequence
3454 Allow the user to select one of ^C, a BREAK signal or BREAK-g
3455 as the sequence to the remote target in order to interrupt the execution.
3456 Ctrl-C is a default. Some system prefers BREAK which is high level of
3457 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
3458 Magic SysRq g. It is BREAK signal and character 'g'.
3460 set remote interrupt-on-connect [on | off]
3461 show remote interrupt-on-connect
3462 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
3463 remote target when gdb connects to it. This is needed when you debug
3466 set remotebreak [on | off]
3468 Deprecated. Use "set/show remote interrupt-sequence" instead.
3470 tvariable $NAME [ = EXP ]
3471 Create or modify a trace state variable.
3474 List trace state variables and their values.
3476 delete tvariable $NAME ...
3477 Delete one or more trace state variables.
3480 Evaluate the given expressions without collecting anything into the
3481 trace buffer. (Valid in tracepoint actions only.)
3483 ftrace FN / FILE:LINE / *ADDR
3484 Define a fast tracepoint at the given function, line, or address.
3486 * New expression syntax
3488 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
3489 GDB now parses 0b101010 identically with 42.
3493 set follow-exec-mode new|same
3494 show follow-exec-mode
3495 Control whether GDB reuses the same inferior across an exec call or
3496 creates a new one. This is useful to be able to restart the old
3497 executable after the inferior having done an exec call.
3499 set default-collect EXPR, ...
3500 show default-collect
3501 Define a list of expressions to be collected at each tracepoint.
3502 This is a useful way to ensure essential items are not overlooked,
3503 such as registers or a critical global variable.
3505 set disconnected-tracing
3506 show disconnected-tracing
3507 If set to 1, the target is instructed to continue tracing if it
3508 loses its connection to GDB. If 0, the target is to stop tracing
3511 set circular-trace-buffer
3512 show circular-trace-buffer
3513 If set to on, the target is instructed to use a circular trace buffer
3514 and discard the oldest trace frames instead of stopping the trace due
3515 to a full trace buffer. If set to off, the trace stops when the buffer
3516 fills up. Some targets may not support this.
3518 set script-extension off|soft|strict
3519 show script-extension
3520 If set to "off", the debugger does not perform any script language
3521 recognition, and all sourced files are assumed to be GDB scripts.
3522 If set to "soft" (the default), files are sourced according to
3523 filename extension, falling back to GDB scripts if the first
3525 If set to "strict", files are sourced according to filename extension.
3527 set ada trust-PAD-over-XVS on|off
3528 show ada trust-PAD-over-XVS
3529 If off, activate a workaround against a bug in the debugging information
3530 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
3531 the GCC sources for more information about the GNAT encoding and
3532 PAD types in particular). It is always safe to set this option to
3533 off, but this introduces a slight performance penalty. The default
3536 * Python API Improvements
3538 ** GDB provides the new class gdb.LazyString. This is useful in
3539 some pretty-printing cases. The new method gdb.Value.lazy_string
3540 provides a simple way to create objects of this type.
3542 ** The fields returned by gdb.Type.fields now have an
3543 `is_base_class' attribute.
3545 ** The new method gdb.Type.range returns the range of an array type.
3547 ** The new method gdb.parse_and_eval can be used to parse and
3548 evaluate an expression.
3550 * New remote packets
3553 Define a trace state variable.
3556 Get the current value of a trace state variable.
3559 Set desired tracing behavior upon disconnection.
3562 Set the trace buffer to be linear or circular.
3565 Get data about the tracepoints currently in use.
3569 Process record now works correctly with hardware watchpoints.
3571 Multiple bug fixes have been made to the mips-irix port, making it
3572 much more reliable. In particular:
3573 - Debugging threaded applications is now possible again. Previously,
3574 GDB would hang while starting the program, or while waiting for
3575 the program to stop at a breakpoint.
3576 - Attaching to a running process no longer hangs.
3577 - An error occurring while loading a core file has been fixed.
3578 - Changing the value of the PC register now works again. This fixes
3579 problems observed when using the "jump" command, or when calling
3580 a function from GDB, or even when assigning a new value to $pc.
3581 - With the "finish" and "return" commands, the return value for functions
3582 returning a small array is now correctly printed.
3583 - It is now possible to break on shared library code which gets executed
3584 during a shared library init phase (code executed while executing
3585 their .init section). Previously, the breakpoint would have no effect.
3586 - GDB is now able to backtrace through the signal handler for
3587 non-threaded programs.
3589 PIE (Position Independent Executable) programs debugging is now supported.
3590 This includes debugging execution of PIC (Position Independent Code) shared
3591 libraries although for that, it should be possible to run such libraries as an
3594 *** Changes in GDB 7.0
3596 * GDB now has an interface for JIT compilation. Applications that
3597 dynamically generate code can create symbol files in memory and register
3598 them with GDB. For users, the feature should work transparently, and
3599 for JIT developers, the interface is documented in the GDB manual in the
3600 "JIT Compilation Interface" chapter.
3602 * Tracepoints may now be conditional. The syntax is as for
3603 breakpoints; either an "if" clause appended to the "trace" command,
3604 or the "condition" command is available. GDB sends the condition to
3605 the target for evaluation using the same bytecode format as is used
3606 for tracepoint actions.
3608 * The disassemble command now supports: an optional /r modifier, print the
3609 raw instructions in hex as well as in symbolic form, and an optional /m
3610 modifier to print mixed source+assembly.
3612 * Process record and replay
3614 In a architecture environment that supports ``process record and
3615 replay'', ``process record and replay'' target can record a log of
3616 the process execution, and replay it with both forward and reverse
3619 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
3620 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
3621 set execution-direction {forward|reverse}, for targets that support
3624 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
3625 feature is available with a native GDB running on kernel version
3628 * GDB now has support for multi-byte and wide character sets on the
3629 target. Strings whose character type is wchar_t, char16_t, or
3630 char32_t are now correctly printed. GDB supports wide- and unicode-
3631 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
3632 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
3633 `printf'. This feature requires iconv to work properly; if your
3634 system does not have a working iconv, GDB can use GNU libiconv. See
3635 the installation instructions for more information.
3637 * GDB now supports automatic retrieval of shared library files from
3638 remote targets. To use this feature, specify a system root that begins
3639 with the `remote:' prefix, either via the `set sysroot' command or via
3640 the `--with-sysroot' configure-time option.
3642 * "info sharedlibrary" now takes an optional regex of libraries to show,
3643 and it now reports if a shared library has no debugging information.
3645 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
3646 now complete on file names.
3648 * When completing in expressions, gdb will attempt to limit
3649 completions to allowable structure or union fields, where appropriate.
3650 For instance, consider:
3652 # struct example { int f1; double f2; };
3653 # struct example variable;
3656 If the user types TAB at the end of this command line, the available
3657 completions will be "f1" and "f2".
3659 * Inlined functions are now supported. They show up in backtraces, and
3660 the "step", "next", and "finish" commands handle them automatically.
3662 * GDB now supports the token-splicing (##) and stringification (#)
3663 operators when expanding macros. It also supports variable-arity
3666 * GDB now supports inspecting extra signal information, exported by
3667 the new $_siginfo convenience variable. The feature is currently
3668 implemented on linux ARM, i386 and amd64.
3670 * GDB can now display the VFP floating point registers and NEON vector
3671 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
3672 can provide these registers (requires Linux 2.6.30 or later). Remote
3673 and simulator targets may also provide them.
3675 * New remote packets
3678 Search memory for a sequence of bytes.
3681 Turn off `+'/`-' protocol acknowledgments to permit more efficient
3682 operation over reliable transport links. Use of this packet is
3683 controlled by the `set remote noack-packet' command.
3686 Kill the process with the specified process ID. Use this in preference
3687 to `k' when multiprocess protocol extensions are supported.
3690 Obtains additional operating system information
3694 Read or write additional signal information.
3696 * Removed remote protocol undocumented extension
3698 An undocumented extension to the remote protocol's `S' stop reply
3699 packet that permited the stub to pass a process id was removed.
3700 Remote servers should use the `T' stop reply packet instead.
3702 * GDB now supports multiple function calling conventions according to the
3703 DWARF-2 DW_AT_calling_convention function attribute.
3705 * The SH target utilizes the aforementioned change to distinguish between gcc
3706 and Renesas calling convention. It also adds the new CLI commands
3707 `set/show sh calling-convention'.
3709 * GDB can now read compressed debug sections, as produced by GNU gold
3710 with the --compress-debug-sections=zlib flag.
3712 * 64-bit core files are now supported on AIX.
3714 * Thread switching is now supported on Tru64.
3716 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
3717 which will be allocated using malloc later in program execution.
3719 * The qXfer:libraries:read remote procotol packet now allows passing a
3720 list of section offsets.
3722 * On GNU/Linux, GDB can now attach to stopped processes. Several race
3723 conditions handling signals delivered during attach or thread creation
3724 have also been fixed.
3726 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
3727 From the user's standpoint, all unqualified instances of True and False
3728 are treated as the standard definitions, regardless of context.
3730 * GDB now parses C++ symbol and type names more flexibly. For
3733 template<typename T> class C { };
3736 GDB will now correctly handle all of:
3738 ptype C<char const *>
3739 ptype C<char const*>
3740 ptype C<const char *>
3741 ptype C<const char*>
3743 * New features in the GDB remote stub, gdbserver
3745 - The "--wrapper" command-line argument tells gdbserver to use a
3746 wrapper program to launch programs for debugging.
3748 - On PowerPC and S/390 targets, it is now possible to use a single
3749 gdbserver executable to debug both 32-bit and 64-bit programs.
3750 (This requires gdbserver itself to be built as a 64-bit executable.)
3752 - gdbserver uses the new noack protocol mode for TCP connections to
3753 reduce communications latency, if also supported and enabled in GDB.
3755 - Support for the sparc64-linux-gnu target is now included in
3758 - The amd64-linux build of gdbserver now supports debugging both
3759 32-bit and 64-bit programs.
3761 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
3762 now support hardware watchpoints, and will use them automatically
3767 GDB now has support for scripting using Python. Whether this is
3768 available is determined at configure time.
3770 New GDB commands can now be written in Python.
3772 * Ada tasking support
3774 Ada tasks can now be inspected in GDB. The following commands have
3778 Print the list of Ada tasks.
3780 Print detailed information about task number N.
3782 Print the task number of the current task.
3784 Switch the context of debugging to task number N.
3786 * Support for user-defined prefixed commands. The "define" command can
3787 add new commands to existing prefixes, e.g. "target".
3789 * Multi-inferior, multi-process debugging.
3791 GDB now has generalized support for multi-inferior debugging. See
3792 "Debugging Multiple Inferiors" in the manual for more information.
3793 Although availability still depends on target support, the command
3794 set is more uniform now. The GNU/Linux specific multi-forks support
3795 has been migrated to this new framework. This implied some user
3796 visible changes; see "New commands" and also "Removed commands"
3799 * Target descriptions can now describe the target OS ABI. See the
3800 "Target Description Format" section in the user manual for more
3803 * Target descriptions can now describe "compatible" architectures
3804 to indicate that the target can execute applications for a different
3805 architecture in addition to those for the main target architecture.
3806 See the "Target Description Format" section in the user manual for
3809 * Multi-architecture debugging.
3811 GDB now includes general supports for debugging applications on
3812 hybrid systems that use more than one single processor architecture
3813 at the same time. Each such hybrid architecture still requires
3814 specific support to be added. The only hybrid architecture supported
3815 in this version of GDB is the Cell Broadband Engine.
3817 * GDB now supports integrated debugging of Cell/B.E. applications that
3818 use both the PPU and SPU architectures. To enable support for hybrid
3819 Cell/B.E. debugging, you need to configure GDB to support both the
3820 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
3821 --enable-targets configure option.
3823 * Non-stop mode debugging.
3825 For some targets, GDB now supports an optional mode of operation in
3826 which you can examine stopped threads while other threads continue
3827 to execute freely. This is referred to as non-stop mode, with the
3828 old mode referred to as all-stop mode. See the "Non-Stop Mode"
3829 section in the user manual for more information.
3831 To be able to support remote non-stop debugging, a remote stub needs
3832 to implement the non-stop mode remote protocol extensions, as
3833 described in the "Remote Non-Stop" section of the user manual. The
3834 GDB remote stub, gdbserver, has been adjusted to support these
3835 extensions on linux targets.
3837 * New commands (for set/show, see "New options" below)
3839 catch syscall [NAME(S) | NUMBER(S)]
3840 Catch system calls. Arguments, which should be names of system
3841 calls or their numbers, mean catch only those syscalls. Without
3842 arguments, every syscall will be caught. When the inferior issues
3843 any of the specified syscalls, GDB will stop and announce the system
3844 call, both when it is called and when its call returns. This
3845 feature is currently available with a native GDB running on the
3846 Linux Kernel, under the following architectures: x86, x86_64,
3847 PowerPC and PowerPC64.
3849 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
3851 Search memory for a sequence of bytes.
3853 maint set python print-stack
3854 maint show python print-stack
3855 Show a stack trace when an error is encountered in a Python script.
3858 Invoke CODE by passing it to the Python interpreter.
3863 These allow macros to be defined, undefined, and listed
3867 Show operating system information about processes.
3870 List the inferiors currently under GDB's control.
3873 Switch focus to inferior number NUM.
3876 Detach from inferior number NUM.
3879 Kill inferior number NUM.
3883 set spu stop-on-load
3884 show spu stop-on-load
3885 Control whether to stop for new SPE threads during Cell/B.E. debugging.
3887 set spu auto-flush-cache
3888 show spu auto-flush-cache
3889 Control whether to automatically flush the software-managed cache
3890 during Cell/B.E. debugging.
3892 set sh calling-convention
3893 show sh calling-convention
3894 Control the calling convention used when calling SH target functions.
3897 show debug timestamp
3898 Control display of timestamps with GDB debugging output.
3900 set disassemble-next-line
3901 show disassemble-next-line
3902 Control display of disassembled source lines or instructions when
3905 set remote noack-packet
3906 show remote noack-packet
3907 Set/show the use of remote protocol QStartNoAckMode packet. See above
3908 under "New remote packets."
3910 set remote query-attached-packet
3911 show remote query-attached-packet
3912 Control use of remote protocol `qAttached' (query-attached) packet.
3914 set remote read-siginfo-object
3915 show remote read-siginfo-object
3916 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
3919 set remote write-siginfo-object
3920 show remote write-siginfo-object
3921 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
3924 set remote reverse-continue
3925 show remote reverse-continue
3926 Control use of remote protocol 'bc' (reverse-continue) packet.
3928 set remote reverse-step
3929 show remote reverse-step
3930 Control use of remote protocol 'bs' (reverse-step) packet.
3932 set displaced-stepping
3933 show displaced-stepping
3934 Control displaced stepping mode. Displaced stepping is a way to
3935 single-step over breakpoints without removing them from the debuggee.
3936 Also known as "out-of-line single-stepping".
3939 show debug displaced
3940 Control display of debugging info for displaced stepping.
3942 maint set internal-error
3943 maint show internal-error
3944 Control what GDB does when an internal error is detected.
3946 maint set internal-warning
3947 maint show internal-warning
3948 Control what GDB does when an internal warning is detected.
3953 Use a wrapper program to launch programs for debugging.
3955 set multiple-symbols (all|ask|cancel)
3956 show multiple-symbols
3957 The value of this variable can be changed to adjust the debugger behavior
3958 when an expression or a breakpoint location contains an ambiguous symbol
3959 name (an overloaded function name, for instance).
3961 set breakpoint always-inserted
3962 show breakpoint always-inserted
3963 Keep breakpoints always inserted in the target, as opposed to inserting
3964 them when resuming the target, and removing them when the target stops.
3965 This option can improve debugger performance on slow remote targets.
3967 set arm fallback-mode (arm|thumb|auto)
3968 show arm fallback-mode
3969 set arm force-mode (arm|thumb|auto)
3971 These commands control how ARM GDB determines whether instructions
3972 are ARM or Thumb. The default for both settings is auto, which uses
3973 the current CPSR value for instructions without symbols; previous
3974 versions of GDB behaved as if "set arm fallback-mode arm".
3976 set disable-randomization
3977 show disable-randomization
3978 Standalone programs run with the virtual address space randomization enabled
3979 by default on some platforms. This option keeps the addresses stable across
3980 multiple debugging sessions.
3984 Control whether other threads are stopped or not when some thread hits
3989 Requests that asynchronous execution is enabled in the target, if available.
3990 In this case, it's possible to resume target in the background, and interact
3991 with GDB while the target is running. "show target-async" displays the
3992 current state of asynchronous execution of the target.
3994 set target-wide-charset
3995 show target-wide-charset
3996 The target-wide-charset is the name of the character set that GDB
3997 uses when printing characters whose type is wchar_t.
3999 set tcp auto-retry (on|off)
4001 set tcp connect-timeout
4002 show tcp connect-timeout
4003 These commands allow GDB to retry failed TCP connections to a remote stub
4004 with a specified timeout period; this is useful if the stub is launched
4005 in parallel with GDB but may not be ready to accept connections immediately.
4007 set libthread-db-search-path
4008 show libthread-db-search-path
4009 Control list of directories which GDB will search for appropriate
4012 set schedule-multiple (on|off)
4013 show schedule-multiple
4014 Allow GDB to resume all threads of all processes or only threads of
4015 the current process.
4019 Use more aggressive caching for accesses to the stack. This improves
4020 performance of remote debugging (particularly backtraces) without
4021 affecting correctness.
4023 set interactive-mode (on|off|auto)
4024 show interactive-mode
4025 Control whether GDB runs in interactive mode (on) or not (off).
4026 When in interactive mode, GDB waits for the user to answer all
4027 queries. Otherwise, GDB does not wait and assumes the default
4028 answer. When set to auto (the default), GDB determines which
4029 mode to use based on the stdin settings.
4034 For program forks, this is replaced by the new more generic `info
4035 inferiors' command. To list checkpoints, you can still use the
4036 `info checkpoints' command, which was an alias for the `info forks'
4040 Replaced by the new `inferior' command. To switch between
4041 checkpoints, you can still use the `restart' command, which was an
4042 alias for the `fork' command.
4045 This is removed, since some targets don't have a notion of
4046 processes. To switch between processes, you can still use the
4047 `inferior' command using GDB's own inferior number.
4050 For program forks, this is replaced by the new more generic `kill
4051 inferior' command. To delete a checkpoint, you can still use the
4052 `delete checkpoint' command, which was an alias for the `delete
4056 For program forks, this is replaced by the new more generic `detach
4057 inferior' command. To detach a checkpoint, you can still use the
4058 `detach checkpoint' command, which was an alias for the `detach
4061 * New native configurations
4063 x86/x86_64 Darwin i[34567]86-*-darwin*
4065 x86_64 MinGW x86_64-*-mingw*
4069 Lattice Mico32 lm32-*
4070 x86 DICOS i[34567]86-*-dicos*
4071 x86_64 DICOS x86_64-*-dicos*
4074 * The GDB remote stub, gdbserver, now supports x86 Windows CE
4075 (mingw32ce) debugging.
4081 These commands were actually not implemented on any target.
4083 *** Changes in GDB 6.8
4085 * New native configurations
4087 NetBSD/hppa hppa*-*netbsd*
4088 Xtensa GNU/Linux xtensa*-*-linux*
4092 NetBSD/hppa hppa*-*-netbsd*
4093 Xtensa GNU/Lunux xtensa*-*-linux*
4095 * Change in command line behavior -- corefiles vs. process ids.
4097 When the '-p NUMBER' or '--pid NUMBER' options are used, and
4098 attaching to process NUMBER fails, GDB no longer attempts to open a
4099 core file named NUMBER. Attaching to a program using the -c option
4100 is no longer supported. Instead, use the '-p' or '--pid' options.
4102 * GDB can now be built as a native debugger for debugging Windows x86
4103 (mingw32) Portable Executable (PE) programs.
4105 * Pending breakpoints no longer change their number when their address
4108 * GDB now supports breakpoints with multiple locations,
4109 including breakpoints on C++ constructors, inside C++ templates,
4110 and in inlined functions.
4112 * GDB's ability to debug optimized code has been improved. GDB more
4113 accurately identifies function bodies and lexical blocks that occupy
4114 more than one contiguous range of addresses.
4116 * Target descriptions can now describe registers for PowerPC.
4118 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
4119 registers on PowerPC targets.
4121 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
4122 targets even when the libthread_db library is not available.
4124 * The GDB remote stub, gdbserver, now supports the new file transfer
4125 commands (remote put, remote get, and remote delete).
4127 * The GDB remote stub, gdbserver, now supports run and attach in
4128 extended-remote mode.
4130 * hppa*64*-*-hpux11* target broken
4131 The debugger is unable to start a program and fails with the following
4132 error: "Error trying to get information about dynamic linker".
4133 The gdb-6.7 release is also affected.
4135 * GDB now supports the --enable-targets= configure option to allow
4136 building a single GDB executable that supports multiple remote
4137 target architectures.
4139 * GDB now supports debugging C and C++ programs which use the
4140 Decimal Floating Point extension. In addition, the PowerPC target
4141 now has a set of pseudo-registers to inspect decimal float values
4142 stored in two consecutive float registers.
4144 * The -break-insert MI command can optionally create pending
4147 * Improved support for debugging Ada
4148 Many improvements to the Ada language support have been made. These
4150 - Better support for Ada2005 interface types
4151 - Improved handling of arrays and slices in general
4152 - Better support for Taft-amendment types
4153 - The '{type} ADDRESS' expression is now allowed on the left hand-side
4155 - Improved command completion in Ada
4158 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
4163 set print frame-arguments (all|scalars|none)
4164 show print frame-arguments
4165 The value of this variable can be changed to control which argument
4166 values should be printed by the debugger when displaying a frame.
4171 Transfer files to and from a remote target, and delete remote files.
4178 Transfer files to and from a remote target, and delete remote files.
4180 * New remote packets
4187 Open, close, read, write, and delete files on the remote system.
4190 Attach to an existing process on the remote system, in extended-remote
4194 Run a new process on the remote system, in extended-remote mode.
4196 *** Changes in GDB 6.7
4198 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
4199 bfd, libiberty and opcodes, as revealed by static analysis donated by
4200 Coverity, Inc. (http://scan.coverity.com).
4202 * When looking up multiply-defined global symbols, GDB will now prefer the
4203 symbol definition in the current shared library if it was built using the
4204 -Bsymbolic linker option.
4206 * When the Text User Interface (TUI) is not configured, GDB will now
4207 recognize the -tui command-line option and print a message that the TUI
4210 * The GDB remote stub, gdbserver, now has lower overhead for high
4211 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
4213 * GDB for MIPS targets now autodetects whether a remote target provides
4214 32-bit or 64-bit register values.
4216 * Support for C++ member pointers has been improved.
4218 * GDB now understands XML target descriptions, which specify the
4219 target's overall architecture. GDB can read a description from
4220 a local file or over the remote serial protocol.
4222 * Vectors of single-byte data use a new integer type which is not
4223 automatically displayed as character or string data.
4225 * The /s format now works with the print command. It displays
4226 arrays of single-byte integers and pointers to single-byte integers
4229 * Target descriptions can now describe target-specific registers,
4230 for architectures which have implemented the support (currently
4231 only ARM, M68K, and MIPS).
4233 * GDB and the GDB remote stub, gdbserver, now support the XScale
4236 * The GDB remote stub, gdbserver, has been updated to support
4237 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
4238 has been rewritten to use the standard GDB remote protocol.
4240 * GDB can now step into C++ functions which are called through thunks.
4242 * GDB for the Cell/B.E. SPU now supports overlay debugging.
4244 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
4245 layout. It also supports a TextSeg= and DataSeg= response when only
4246 segment base addresses (rather than offsets) are available.
4248 * The /i format now outputs any trailing branch delay slot instructions
4249 immediately following the last instruction within the count specified.
4251 * The GDB remote protocol "T" stop reply packet now supports a
4252 "library" response. Combined with the new "qXfer:libraries:read"
4253 packet, this response allows GDB to debug shared libraries on targets
4254 where the operating system manages the list of loaded libraries (e.g.
4255 Windows and SymbianOS).
4257 * The GDB remote stub, gdbserver, now supports dynamic link libraries
4258 (DLLs) on Windows and Windows CE targets.
4260 * GDB now supports a faster verification that a .debug file matches its binary
4261 according to its build-id signature, if the signature is present.
4267 Enable or disable hardware flow control (RTS/CTS) on the serial port
4268 when debugging using remote targets.
4270 set mem inaccessible-by-default
4271 show mem inaccessible-by-default
4272 If the target supplies a memory map, for instance via the remote
4273 protocol's "qXfer:memory-map:read" packet, setting this variable
4274 prevents GDB from accessing memory outside the memory map. This
4275 is useful for targets with memory mapped registers or which react
4276 badly to accesses of unmapped address space.
4278 set breakpoint auto-hw
4279 show breakpoint auto-hw
4280 If the target supplies a memory map, for instance via the remote
4281 protocol's "qXfer:memory-map:read" packet, setting this variable
4282 lets GDB use hardware breakpoints automatically for memory regions
4283 where it can not use software breakpoints. This covers both the
4284 "break" command and internal breakpoints used for other commands
4285 including "next" and "finish".
4288 catch exception unhandled
4289 Stop the program execution when Ada exceptions are raised.
4292 Stop the program execution when an Ada assertion failed.
4296 Set an alternate system root for target files. This is a more
4297 general version of "set solib-absolute-prefix", which is now
4298 an alias to "set sysroot".
4301 Provide extended SPU facility status information. This set of
4302 commands is available only when debugging the Cell/B.E. SPU
4305 * New native configurations
4307 OpenBSD/sh sh*-*openbsd*
4310 unset tdesc filename
4312 Use the specified local file as an XML target description, and do
4313 not query the target for its built-in description.
4317 OpenBSD/sh sh*-*-openbsd*
4318 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
4319 Toshiba Media Processor mep-elf
4321 * New remote packets
4324 Ignore the specified signals; pass them directly to the debugged program
4325 without stopping other threads or reporting them to GDB.
4327 qXfer:features:read:
4328 Read an XML target description from the target, which describes its
4333 Read or write contents of an spufs file on the target system. These
4334 packets are available only on the Cell/B.E. SPU architecture.
4336 qXfer:libraries:read:
4337 Report the loaded shared libraries. Combined with new "T" packet
4338 response, this packet allows GDB to debug shared libraries on
4339 targets where the operating system manages the list of loaded
4340 libraries (e.g. Windows and SymbianOS).
4344 Support for these obsolete configurations has been removed.
4352 i[34567]86-*-lynxos*
4353 i[34567]86-*-netware*
4354 i[34567]86-*-sco3.2v5*
4355 i[34567]86-*-sco3.2v4*
4357 i[34567]86-*-sysv4.2*
4360 i[34567]86-*-unixware2*
4361 i[34567]86-*-unixware*
4370 * Other removed features
4377 Various m68k-only ROM monitors.
4384 Various Renesas ROM monitors and debugging interfaces for SH and
4389 Support for a Macraigor serial interface to on-chip debugging.
4390 GDB does not directly support the newer parallel or USB
4395 A debug information format. The predecessor to DWARF 2 and
4396 DWARF 3, which are still supported.
4398 Support for the HP aCC compiler on HP-UX/PA-RISC
4400 SOM-encapsulated symbolic debugging information, automatic
4401 invocation of pxdb, and the aCC custom C++ ABI. This does not
4402 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
4403 with aCC can still be debugged on an assembly level.
4405 MIPS ".pdr" sections
4407 A MIPS-specific format used to describe stack frame layout
4408 in debugging information.
4412 GDB could work with an older version of Guile to debug
4413 the interpreter and Scheme programs running in it.
4415 set mips stack-arg-size
4416 set mips saved-gpreg-size
4418 Use "set mips abi" to control parameter passing for MIPS.
4420 *** Changes in GDB 6.6
4425 Cell Broadband Engine SPU spu-elf
4427 * GDB can now be configured as a cross-debugger targeting native Windows
4428 (mingw32) or Cygwin. It can communicate with a remote debugging stub
4429 running on a Windows system over TCP/IP to debug Windows programs.
4431 * The GDB remote stub, gdbserver, has been updated to support Windows and
4432 Cygwin debugging. Both single-threaded and multi-threaded programs are
4435 * The "set trust-readonly-sections" command works again. This command was
4436 broken in GDB 6.3, 6.4, and 6.5.
4438 * The "load" command now supports writing to flash memory, if the remote
4439 stub provides the required support.
4441 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
4442 longer requires symbolic debug information (e.g. DWARF-2).
4447 unset substitute-path
4448 show substitute-path
4449 Manage a list of substitution rules that GDB uses to rewrite the name
4450 of the directories where the sources are located. This can be useful
4451 for instance when the sources were moved to a different location
4452 between compilation and debugging.
4456 Print each CLI command as it is executed. Each command is prefixed with
4457 a number of `+' symbols representing the nesting depth.
4458 The source command now has a `-v' option to enable the same feature.
4462 The ARM Demon monitor support (RDP protocol, "target rdp").
4464 Kernel Object Display, an embedded debugging feature which only worked with
4465 an obsolete version of Cisco IOS.
4467 The 'set download-write-size' and 'show download-write-size' commands.
4469 * New remote packets
4472 Tell a stub about GDB client features, and request remote target features.
4473 The first feature implemented is PacketSize, which allows the target to
4474 specify the size of packets it can handle - to minimize the number of
4475 packets required and improve performance when connected to a remote
4479 Fetch an OS auxilliary vector from the remote stub. This packet is a
4480 more efficient replacement for qPart:auxv:read.
4482 qXfer:memory-map:read:
4483 Fetch a memory map from the remote stub, including information about
4484 RAM, ROM, and flash memory devices.
4489 Erase and program a flash memory device.
4491 * Removed remote packets
4494 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
4495 used it, and only gdbserver implemented it.
4497 *** Changes in GDB 6.5
4501 Renesas M32C/M16C m32c-elf
4503 Morpho Technologies ms1 ms1-elf
4507 init-if-undefined Initialize a convenience variable, but
4508 only if it doesn't already have a value.
4510 The following commands are presently only implemented for native GNU/Linux:
4512 checkpoint Save a snapshot of the program state.
4514 restart <n> Return the program state to a
4515 previously saved state.
4517 info checkpoints List currently saved checkpoints.
4519 delete-checkpoint <n> Delete a previously saved checkpoint.
4521 set|show detach-on-fork Tell gdb whether to detach from a newly
4522 forked process, or to keep debugging it.
4524 info forks List forks of the user program that
4525 are available to be debugged.
4527 fork <n> Switch to debugging one of several
4528 forks of the user program that are
4529 available to be debugged.
4531 delete-fork <n> Delete a fork from the list of forks
4532 that are available to be debugged (and
4533 kill the forked process).
4535 detach-fork <n> Delete a fork from the list of forks
4536 that are available to be debugged (and
4537 allow the process to continue).
4541 Morpho Technologies ms2 ms1-elf
4543 * Improved Windows host support
4545 GDB now builds as a cross debugger hosted on i686-mingw32, including
4546 native console support, and remote communications using either
4547 network sockets or serial ports.
4549 * Improved Modula-2 language support
4551 GDB can now print most types in the Modula-2 syntax. This includes:
4552 basic types, set types, record types, enumerated types, range types,
4553 pointer types and ARRAY types. Procedure var parameters are correctly
4554 printed and hexadecimal addresses and character constants are also
4555 written in the Modula-2 syntax. Best results can be obtained by using
4556 GNU Modula-2 together with the -gdwarf-2 command line option.
4560 The ARM rdi-share module.
4562 The Netware NLM debug server.
4564 *** Changes in GDB 6.4
4566 * New native configurations
4568 OpenBSD/arm arm*-*-openbsd*
4569 OpenBSD/mips64 mips64-*-openbsd*
4573 Morpho Technologies ms1 ms1-elf
4575 * New command line options
4577 --batch-silent As for --batch, but totally silent.
4578 --return-child-result The debugger will exist with the same value
4579 the child (debugged) program exited with.
4580 --eval-command COMMAND, -ex COMMAND
4581 Execute a single GDB CLI command. This may be
4582 specified multiple times and in conjunction
4583 with the --command (-x) option.
4585 * Deprecated commands removed
4587 The following commands, that were deprecated in 2000, have been
4591 set|show arm disassembly-flavor set|show arm disassembler
4592 othernames set arm disassembler
4593 set|show remotedebug set|show debug remote
4594 set|show archdebug set|show debug arch
4595 set|show eventdebug set|show debug event
4598 * New BSD user-level threads support
4600 It is now possible to debug programs using the user-level threads
4601 library on OpenBSD and FreeBSD. Currently supported (target)
4604 FreeBSD/amd64 x86_64-*-freebsd*
4605 FreeBSD/i386 i386-*-freebsd*
4606 OpenBSD/i386 i386-*-openbsd*
4608 Note that the new kernel threads libraries introduced in FreeBSD 5.x
4609 are not yet supported.
4611 * New support for Matsushita MN10300 w/sim added
4612 (Work in progress). mn10300-elf.
4614 * REMOVED configurations and files
4616 VxWorks and the XDR protocol *-*-vxworks
4617 Motorola MCORE mcore-*-*
4618 National Semiconductor NS32000 ns32k-*-*
4620 * New "set print array-indexes" command
4622 After turning this setting "on", GDB prints the index of each element
4623 when displaying arrays. The default is "off" to preserve the previous
4626 * VAX floating point support
4628 GDB now supports the not-quite-ieee VAX F and D floating point formats.
4630 * User-defined command support
4632 In addition to using $arg0..$arg9 for argument passing, it is now possible
4633 to use $argc to determine now many arguments have been passed. See the
4634 section on user-defined commands in the user manual for more information.
4636 *** Changes in GDB 6.3:
4638 * New command line option
4640 GDB now accepts -l followed by a number to set the timeout for remote
4643 * GDB works with GCC -feliminate-dwarf2-dups
4645 GDB now supports a more compact representation of DWARF-2 debug
4646 information using DW_FORM_ref_addr references. These are produced
4647 by GCC with the option -feliminate-dwarf2-dups and also by some
4648 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
4649 to use -feliminate-dwarf2-dups.
4651 * Internationalization
4653 When supported by the host system, GDB will be built with
4654 internationalization (libintl). The task of marking up the sources is
4655 continued, we're looking forward to our first translation.
4659 Initial support for debugging programs compiled with the GNAT
4660 implementation of the Ada programming language has been integrated
4661 into GDB. In this release, support is limited to expression evaluation.
4663 * New native configurations
4665 GNU/Linux/m32r m32r-*-linux-gnu
4669 GDB's remote protocol now includes support for the 'p' packet. This
4670 packet is used to fetch individual registers from a remote inferior.
4672 * END-OF-LIFE registers[] compatibility module
4674 GDB's internal register infrastructure has been completely rewritten.
4675 The new infrastructure making possible the implementation of key new
4676 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
4679 GDB 6.3 will be the last release to include the the registers[]
4680 compatibility module that allowed out-of-date configurations to
4681 continue to work. This change directly impacts the following
4691 powerpc bdm protocol
4693 Unless there is activity to revive these configurations, they will be
4694 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
4696 * OBSOLETE configurations and files
4698 Configurations that have been declared obsolete in this release have
4699 been commented out. Unless there is activity to revive these
4700 configurations, the next release of GDB will have their sources
4701 permanently REMOVED.
4710 *** Changes in GDB 6.2.1:
4712 * MIPS `break main; run' gave an heuristic-fence-post warning
4714 When attempting to run even a simple program, a warning about
4715 heuristic-fence-post being hit would be reported. This problem has
4718 * MIPS IRIX 'long double' crashed GDB
4720 When examining a long double variable, GDB would get a segmentation
4721 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
4722 IRIX long double values).
4726 A bug in the VAX stack code was causing problems with the "next"
4727 command. This problem has been fixed.
4729 *** Changes in GDB 6.2:
4731 * Fix for ``many threads''
4733 On GNU/Linux systems that use the NPTL threads library, a program
4734 rapidly creating and deleting threads would confuse GDB leading to the
4737 ptrace: No such process.
4738 thread_db_get_info: cannot get thread info: generic error
4740 This problem has been fixed.
4742 * "-async" and "-noasync" options removed.
4744 Support for the broken "-noasync" option has been removed (it caused
4747 * New ``start'' command.
4749 This command runs the program until the begining of the main procedure.
4751 * New BSD Kernel Data Access Library (libkvm) interface
4753 Using ``target kvm'' it is now possible to debug kernel core dumps and
4754 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
4755 platforms. Currently supported (native-only) configurations are:
4757 FreeBSD/amd64 x86_64-*-freebsd*
4758 FreeBSD/i386 i?86-*-freebsd*
4759 NetBSD/i386 i?86-*-netbsd*
4760 NetBSD/m68k m68*-*-netbsd*
4761 NetBSD/sparc sparc-*-netbsd*
4762 OpenBSD/amd64 x86_64-*-openbsd*
4763 OpenBSD/i386 i?86-*-openbsd*
4764 OpenBSD/m68k m68*-openbsd*
4765 OpenBSD/sparc sparc-*-openbsd*
4767 * Signal trampoline code overhauled
4769 Many generic problems with GDB's signal handling code have been fixed.
4770 These include: backtraces through non-contiguous stacks; recognition
4771 of sa_sigaction signal trampolines; backtrace from a NULL pointer
4772 call; backtrace through a signal trampoline; step into and out of
4773 signal handlers; and single-stepping in the signal trampoline.
4775 Please note that kernel bugs are a limiting factor here. These
4776 features have been shown to work on an s390 GNU/Linux system that
4777 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
4779 * Cygwin support for DWARF 2 added.
4781 * New native configurations
4783 GNU/Linux/hppa hppa*-*-linux*
4784 OpenBSD/hppa hppa*-*-openbsd*
4785 OpenBSD/m68k m68*-*-openbsd*
4786 OpenBSD/m88k m88*-*-openbsd*
4787 OpenBSD/powerpc powerpc-*-openbsd*
4788 NetBSD/vax vax-*-netbsd*
4789 OpenBSD/vax vax-*-openbsd*
4791 * END-OF-LIFE frame compatibility module
4793 GDB's internal frame infrastructure has been completely rewritten.
4794 The new infrastructure making it possible to support key new features
4795 including DWARF 2 Call Frame Information. To aid in the task of
4796 migrating old configurations to this new infrastructure, a
4797 compatibility module, that allowed old configurations to continue to
4798 work, was also included.
4800 GDB 6.2 will be the last release to include this frame compatibility
4801 module. This change directly impacts the following configurations:
4811 Unless there is activity to revive these configurations, they will be
4812 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
4814 * REMOVED configurations and files
4816 Sun 3, running SunOS 3 m68*-*-sunos3*
4817 Sun 3, running SunOS 4 m68*-*-sunos4*
4818 Sun 2, running SunOS 3 m68000-*-sunos3*
4819 Sun 2, running SunOS 4 m68000-*-sunos4*
4820 Motorola 680x0 running LynxOS m68*-*-lynxos*
4821 AT&T 3b1/Unix pc m68*-att-*
4822 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4823 decstation mips-dec-* mips-little-*
4824 riscos mips-*-riscos* mips-*-sysv*
4825 sonymips mips-sony-*
4826 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4828 *** Changes in GDB 6.1.1:
4830 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
4832 The TUI (Text-mode User Interface) is now built as part of a default
4833 GDB configuration. It is enabled by either selecting the TUI with the
4834 command line option "-i=tui" or by running the separate "gdbtui"
4835 program. For more information on the TUI, see the manual "Debugging
4838 * Pending breakpoint support (also included in GDB 6.1)
4840 Support has been added to allow you to specify breakpoints in shared
4841 libraries that have not yet been loaded. If a breakpoint location
4842 cannot be found, and the "breakpoint pending" option is set to auto,
4843 GDB queries you if you wish to make the breakpoint pending on a future
4844 shared-library load. If and when GDB resolves the breakpoint symbol,
4845 the pending breakpoint is removed as one or more regular breakpoints
4848 Pending breakpoints are very useful for GCJ Java debugging.
4850 * Fixed ISO-C build problems
4852 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
4853 non ISO-C code that stopped them being built using a more strict ISO-C
4854 compiler (e.g., IBM's C compiler).
4856 * Fixed build problem on IRIX 5
4858 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
4859 wasn't able to compile compile on an IRIX 5 system.
4861 * Added execute permission to gdb/gdbserver/configure
4863 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
4864 permission. This bug would cause configure to fail on a number of
4865 systems (Solaris, IRIX). Ref: server/519.
4867 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
4869 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
4870 has been updated to use constant array sizes.
4872 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
4874 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
4875 its generated DWARF Call Frame Info. This encoding was causing GDB to
4876 panic, that panic has been fixed. Ref: gdb/1628.
4878 * Fixed a problem when examining parameters in shared library code.
4880 When examining parameters in optimized shared library code generated
4881 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
4882 not available''. GDB now correctly displays the variable's value.
4884 *** Changes in GDB 6.1:
4886 * Removed --with-mmalloc
4888 Support for the mmalloc memory manager has been removed, as it
4889 conflicted with the internal gdb byte cache.
4891 * Changes in AMD64 configurations
4893 The AMD64 target now includes the %cs and %ss registers. As a result
4894 the AMD64 remote protocol has changed; this affects the floating-point
4895 and SSE registers. If you rely on those registers for your debugging,
4896 you should upgrade gdbserver on the remote side.
4898 * Revised SPARC target
4900 The SPARC target has been completely revised, incorporating the
4901 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
4902 support for LynxOS and SunOS 4 has been dropped. Calling functions
4903 from within GDB on operating systems with a non-executable stack
4904 (Solaris, OpenBSD) now works.
4908 GDB has a new C++ demangler which does a better job on the mangled
4909 names generated by current versions of g++. It also runs faster, so
4910 with this and other changes gdb should now start faster on large C++
4913 * DWARF 2 Location Expressions
4915 GDB support for location expressions has been extended to support function
4916 arguments and frame bases. Older versions of GDB could crash when they
4919 * C++ nested types and namespaces
4921 GDB's support for nested types and namespaces in C++ has been
4922 improved, especially if you use the DWARF 2 debugging format. (This
4923 is the default for recent versions of GCC on most platforms.)
4924 Specifically, if you have a class "Inner" defined within a class or
4925 namespace "Outer", then GDB realizes that the class's name is
4926 "Outer::Inner", not simply "Inner". This should greatly reduce the
4927 frequency of complaints about not finding RTTI symbols. In addition,
4928 if you are stopped at inside of a function defined within a namespace,
4929 GDB modifies its name lookup accordingly.
4931 * New native configurations
4933 NetBSD/amd64 x86_64-*-netbsd*
4934 OpenBSD/amd64 x86_64-*-openbsd*
4935 OpenBSD/alpha alpha*-*-openbsd*
4936 OpenBSD/sparc sparc-*-openbsd*
4937 OpenBSD/sparc64 sparc64-*-openbsd*
4939 * New debugging protocols
4941 M32R with SDI protocol m32r-*-elf*
4943 * "set prompt-escape-char" command deleted.
4945 The command "set prompt-escape-char" has been deleted. This command,
4946 and its very obscure effet on GDB's prompt, was never documented,
4947 tested, nor mentioned in the NEWS file.
4949 * OBSOLETE configurations and files
4951 Configurations that have been declared obsolete in this release have
4952 been commented out. Unless there is activity to revive these
4953 configurations, the next release of GDB will have their sources
4954 permanently REMOVED.
4956 Sun 3, running SunOS 3 m68*-*-sunos3*
4957 Sun 3, running SunOS 4 m68*-*-sunos4*
4958 Sun 2, running SunOS 3 m68000-*-sunos3*
4959 Sun 2, running SunOS 4 m68000-*-sunos4*
4960 Motorola 680x0 running LynxOS m68*-*-lynxos*
4961 AT&T 3b1/Unix pc m68*-att-*
4962 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
4963 decstation mips-dec-* mips-little-*
4964 riscos mips-*-riscos* mips-*-sysv*
4965 sonymips mips-sony-*
4966 sysv mips*-*-sysv4* (IRIX 5/6 not included)
4968 * REMOVED configurations and files
4970 SGI Irix-4.x mips-sgi-irix4 or iris4
4971 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4972 Z8000 simulator z8k-zilog-none or z8ksim
4973 Matsushita MN10200 w/simulator mn10200-*-*
4974 H8/500 simulator h8500-hitachi-hms or h8500hms
4975 HP/PA running BSD hppa*-*-bsd*
4976 HP/PA running OSF/1 hppa*-*-osf*
4977 HP/PA Pro target hppa*-*-pro*
4978 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
4979 386BSD i[3456]86-*-bsd*
4980 Sequent family i[3456]86-sequent-sysv4*
4981 i[3456]86-sequent-sysv*
4982 i[3456]86-sequent-bsd*
4983 SPARC running LynxOS sparc-*-lynxos*
4984 SPARC running SunOS 4 sparc-*-sunos4*
4985 Tsqware Sparclet sparclet-*-*
4986 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4988 *** Changes in GDB 6.0:
4992 Support for debugging the Objective-C programming language has been
4993 integrated into GDB.
4995 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
4997 DWARF 2's Call Frame Information makes available compiler generated
4998 information that more exactly describes the program's run-time stack.
4999 By using this information, GDB is able to provide more robust stack
5002 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
5003 have been updated to use a new backtrace mechanism which includes
5004 DWARF 2 CFI support.
5008 GDB's remote protocol has been extended to include support for hosted
5009 file I/O (where the remote target uses GDB's file system). See GDB's
5010 remote protocol documentation for details.
5012 * All targets using the new architecture framework.
5014 All of GDB's targets have been updated to use the new internal
5015 architecture framework. The way is now open for future GDB releases
5016 to include cross-architecture native debugging support (i386 on amd64,
5019 * GNU/Linux's Thread Local Storage (TLS)
5021 GDB now includes support for for the GNU/Linux implementation of
5022 per-thread variables.
5024 * GNU/Linux's Native POSIX Thread Library (NPTL)
5026 GDB's thread code has been updated to work with either the new
5027 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
5029 * Separate debug info.
5031 GDB, in conjunction with BINUTILS, now supports a mechanism for
5032 automatically loading debug information from a separate file. Instead
5033 of shipping full debug and non-debug versions of system libraries,
5034 system integrators can now instead ship just the stripped libraries
5035 and optional debug files.
5037 * DWARF 2 Location Expressions
5039 DWARF 2 Location Expressions allow the compiler to more completely
5040 describe the location of variables (even in optimized code) to the
5043 GDB now includes preliminary support for location expressions (support
5044 for DW_OP_piece is still missing).
5048 A number of long standing bugs that caused GDB to die while starting a
5049 Java application have been fixed. GDB's Java support is now
5050 considered "useable".
5052 * GNU/Linux support for fork, vfork, and exec.
5054 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
5055 commands are now implemented for GNU/Linux. They require a 2.5.x or later
5058 * GDB supports logging output to a file
5060 There are two new commands, "set logging" and "show logging", which can be
5061 used to capture GDB's output to a file.
5063 * The meaning of "detach" has changed for gdbserver
5065 The "detach" command will now resume the application, as documented. To
5066 disconnect from gdbserver and leave it stopped, use the new "disconnect"
5069 * d10v, m68hc11 `regs' command deprecated
5071 The `info registers' command has been updated so that it displays the
5072 registers using a format identical to the old `regs' command.
5076 A new command, "maint set profile on/off", has been added. This command can
5077 be used to enable or disable profiling while running GDB, to profile a
5078 session or a set of commands. In addition there is a new configure switch,
5079 "--enable-profiling", which will cause GDB to be compiled with profiling
5080 data, for more informative profiling results.
5082 * Default MI syntax changed to "mi2".
5084 The default MI (machine interface) syntax, enabled by the command line
5085 option "-i=mi", has been changed to "mi2". The previous MI syntax,
5086 "mi1", can be enabled by specifying the option "-i=mi1".
5088 Support for the original "mi0" syntax (included in GDB 5.0) has been
5091 Fix for gdb/192: removed extraneous space when displaying frame level.
5092 Fix for gdb/672: update changelist is now output in mi list format.
5093 Fix for gdb/702: a -var-assign that updates the value now shows up
5094 in a subsequent -var-update.
5096 * New native configurations.
5098 FreeBSD/amd64 x86_64-*-freebsd*
5100 * Multi-arched targets.
5102 HP/PA HPUX11 hppa*-*-hpux*
5103 Renesas M32R/D w/simulator m32r-*-elf*
5105 * OBSOLETE configurations and files
5107 Configurations that have been declared obsolete in this release have
5108 been commented out. Unless there is activity to revive these
5109 configurations, the next release of GDB will have their sources
5110 permanently REMOVED.
5112 Z8000 simulator z8k-zilog-none or z8ksim
5113 Matsushita MN10200 w/simulator mn10200-*-*
5114 H8/500 simulator h8500-hitachi-hms or h8500hms
5115 HP/PA running BSD hppa*-*-bsd*
5116 HP/PA running OSF/1 hppa*-*-osf*
5117 HP/PA Pro target hppa*-*-pro*
5118 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
5119 Sequent family i[3456]86-sequent-sysv4*
5120 i[3456]86-sequent-sysv*
5121 i[3456]86-sequent-bsd*
5122 Tsqware Sparclet sparclet-*-*
5123 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
5125 * REMOVED configurations and files
5128 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5129 IBM AIX PS/2 i[3456]86-*-aix
5130 i386 running Mach 3.0 i[3456]86-*-mach3*
5131 i386 running Mach i[3456]86-*-mach*
5132 i386 running OSF/1 i[3456]86-*osf1mk*
5133 HP/Apollo 68k Family m68*-apollo*-sysv*,
5135 m68*-hp-bsd*, m68*-hp-hpux*
5136 Argonaut Risc Chip (ARC) arc-*-*
5137 Mitsubishi D30V d30v-*-*
5138 Fujitsu FR30 fr30-*-elf*
5139 OS/9000 i[34]86-*-os9k
5140 I960 with MON960 i960-*-coff
5142 * MIPS $fp behavior changed
5144 The convenience variable $fp, for the MIPS, now consistently returns
5145 the address of the current frame's base. Previously, depending on the
5146 context, $fp could refer to either $sp or the current frame's base
5147 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
5148 The GNU Source-Level Debugger''.
5150 *** Changes in GDB 5.3:
5152 * GNU/Linux shared library multi-threaded performance improved.
5154 When debugging a multi-threaded application on GNU/Linux, GDB now uses
5155 `/proc', in preference to `ptrace' for memory reads. This may result
5156 in an improvement in the start-up time of multi-threaded, shared
5157 library applications when run under GDB. One GDB user writes: ``loads
5158 shared libs like mad''.
5160 * ``gdbserver'' now supports multi-threaded applications on some targets
5162 Support for debugging multi-threaded applications which use
5163 the GNU/Linux LinuxThreads package has been added for
5164 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
5165 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
5167 * GDB now supports C/C++ preprocessor macros.
5169 GDB now expands preprocessor macro invocations in C/C++ expressions,
5170 and provides various commands for showing macro definitions and how
5173 The new command `macro expand EXPRESSION' expands any macro
5174 invocations in expression, and shows the result.
5176 The new command `show macro MACRO-NAME' shows the definition of the
5177 macro named MACRO-NAME, and where it was defined.
5179 Most compilers don't include information about macros in the debugging
5180 information by default. In GCC 3.1, for example, you need to compile
5181 your program with the options `-gdwarf-2 -g3'. If the macro
5182 information is present in the executable, GDB will read it.
5184 * Multi-arched targets.
5186 DEC Alpha (partial) alpha*-*-*
5187 DEC VAX (partial) vax-*-*
5189 National Semiconductor NS32000 (partial) ns32k-*-*
5190 Motorola 68000 (partial) m68k-*-*
5191 Motorola MCORE mcore-*-*
5195 Fujitsu FRV architecture added by Red Hat frv*-*-*
5198 * New native configurations
5200 Alpha NetBSD alpha*-*-netbsd*
5201 SH NetBSD sh*-*-netbsdelf*
5202 MIPS NetBSD mips*-*-netbsd*
5203 UltraSPARC NetBSD sparc64-*-netbsd*
5205 * OBSOLETE configurations and files
5207 Configurations that have been declared obsolete in this release have
5208 been commented out. Unless there is activity to revive these
5209 configurations, the next release of GDB will have their sources
5210 permanently REMOVED.
5212 Mitsubishi D30V d30v-*-*
5213 OS/9000 i[34]86-*-os9k
5214 IBM AIX PS/2 i[3456]86-*-aix
5215 Fujitsu FR30 fr30-*-elf*
5216 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
5217 Argonaut Risc Chip (ARC) arc-*-*
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 I960 with MON960 i960-*-coff
5226 * OBSOLETE languages
5228 CHILL, a Pascal like language used by telecommunications companies.
5230 * REMOVED configurations and files
5232 AMD 29k family via UDI a29k-amd-udi, udi29k
5233 A29K VxWorks a29k-*-vxworks
5234 AMD 29000 embedded, using EBMON a29k-none-none
5235 AMD 29000 embedded with COFF a29k-none-coff
5236 AMD 29000 embedded with a.out a29k-none-aout
5238 testsuite/gdb.hp/gdb.threads-hp/ directory
5240 * New command "set max-user-call-depth <nnn>"
5242 This command allows the user to limit the call depth of user-defined
5243 commands. The default is 1024.
5245 * Changes in FreeBSD/i386 native debugging.
5247 Support for the "generate-core-file" has been added.
5249 * New commands "dump", "append", and "restore".
5251 These commands allow data to be copied from target memory
5252 to a bfd-format or binary file (dump and append), and back
5253 from a file into memory (restore).
5255 * Improved "next/step" support on multi-processor Alpha Tru64.
5257 The previous single-step mechanism could cause unpredictable problems,
5258 including the random appearance of SIGSEGV or SIGTRAP signals. The use
5259 of a software single-step mechanism prevents this.
5261 *** Changes in GDB 5.2.1:
5269 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
5270 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
5271 Fix, by Joel Brobecker imported from mainline.
5273 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
5274 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
5275 Fix, by Fred Fish, imported from mainline.
5277 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
5278 Surprisingly enough, it works now.
5279 By Michal Ludvig, imported from mainline.
5281 i386 hardware watchpoint support:
5282 avoid misses on second run for some targets.
5283 By Pierre Muller, imported from mainline.
5285 *** Changes in GDB 5.2:
5287 * New command "set trust-readonly-sections on[off]".
5289 This command is a hint that tells gdb that read-only sections
5290 really are read-only (ie. that their contents will not change).
5291 In this mode, gdb will go to the object file rather than the
5292 target to read memory from read-only sections (such as ".text").
5293 This can be a significant performance improvement on some
5294 (notably embedded) targets.
5296 * New command "generate-core-file" (or "gcore").
5298 This new gdb command allows the user to drop a core file of the child
5299 process state at any time. So far it's been implemented only for
5300 GNU/Linux and Solaris, but should be relatively easily ported to other
5301 hosts. Argument is core file name (defaults to core.<pid>).
5303 * New command line option
5305 GDB now accepts --pid or -p followed by a process id.
5307 * Change in command line behavior -- corefiles vs. process ids.
5309 There is a subtle behavior in the way in which GDB handles
5310 command line arguments. The first non-flag argument is always
5311 a program to debug, but the second non-flag argument may either
5312 be a corefile or a process id. Previously, GDB would attempt to
5313 open the second argument as a corefile, and if that failed, would
5314 issue a superfluous error message and then attempt to attach it as
5315 a process. Now, if the second argument begins with a non-digit,
5316 it will be treated as a corefile. If it begins with a digit,
5317 GDB will attempt to attach it as a process, and if no such process
5318 is found, will then attempt to open it as a corefile.
5320 * Changes in ARM configurations.
5322 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
5323 configuration is fully multi-arch.
5325 * New native configurations
5327 ARM NetBSD arm*-*-netbsd*
5328 x86 OpenBSD i[3456]86-*-openbsd*
5329 AMD x86-64 running GNU/Linux x86_64-*-linux-*
5330 Sparc64 running FreeBSD sparc64-*-freebsd*
5334 Sanyo XStormy16 xstormy16-elf
5336 * OBSOLETE configurations and files
5338 Configurations that have been declared obsolete in this release have
5339 been commented out. Unless there is activity to revive these
5340 configurations, the next release of GDB will have their sources
5341 permanently REMOVED.
5343 AMD 29k family via UDI a29k-amd-udi, udi29k
5344 A29K VxWorks a29k-*-vxworks
5345 AMD 29000 embedded, using EBMON a29k-none-none
5346 AMD 29000 embedded with COFF a29k-none-coff
5347 AMD 29000 embedded with a.out a29k-none-aout
5349 testsuite/gdb.hp/gdb.threads-hp/ directory
5351 * REMOVED configurations and files
5353 TI TMS320C80 tic80-*-*
5355 PowerPC Solaris powerpcle-*-solaris*
5356 PowerPC Windows NT powerpcle-*-cygwin32
5357 PowerPC Netware powerpc-*-netware*
5358 Harris/CXUX m88k m88*-harris-cxux*
5359 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5360 ns32k-utek-sysv* ns32k-utek-*
5361 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5362 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5363 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5364 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5365 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
5367 * Changes to command line processing
5369 The new `--args' feature can be used to specify command-line arguments
5370 for the inferior from gdb's command line.
5372 * Changes to key bindings
5374 There is a new `operate-and-get-next' function bound to `C-o'.
5376 *** Changes in GDB 5.1.1
5378 Fix compile problem on DJGPP.
5380 Fix a problem with floating-point registers on the i386 being
5383 Fix to stop GDB crashing on .debug_str debug info.
5385 Numerous documentation fixes.
5387 Numerous testsuite fixes.
5389 *** Changes in GDB 5.1:
5391 * New native configurations
5393 Alpha FreeBSD alpha*-*-freebsd*
5394 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
5395 MIPS GNU/Linux mips*-*-linux*
5396 MIPS SGI Irix 6.x mips*-sgi-irix6*
5397 ia64 AIX ia64-*-aix*
5398 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
5402 Motorola 68HC11 and 68HC12 m68hc11-elf
5404 UltraSparc running GNU/Linux sparc64-*-linux*
5406 * OBSOLETE configurations and files
5408 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
5409 Harris/CXUX m88k m88*-harris-cxux*
5410 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
5411 ns32k-utek-sysv* ns32k-utek-*
5412 TI TMS320C80 tic80-*-*
5414 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
5415 PowerPC Solaris powerpcle-*-solaris*
5416 PowerPC Windows NT powerpcle-*-cygwin32
5417 PowerPC Netware powerpc-*-netware*
5418 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
5419 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
5420 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
5421 Apple Macintosh (MPW) host N/A
5423 stuff.c (Program to stuff files into a specially prepared space in kdb)
5424 kdb-start.c (Main loop for the standalone kernel debugger)
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 * REMOVED configurations and files
5433 Altos 3068 m68*-altos-*
5434 Convex c1-*-*, c2-*-*
5436 ARM RISCix arm-*-* (as host)
5440 * GDB has been converted to ISO C.
5442 GDB's source code has been converted to ISO C. In particular, the
5443 sources are fully protoized, and rely on standard headers being
5448 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
5450 * The MI enabled by default.
5452 The new machine oriented interface (MI) introduced in GDB 5.0 has been
5453 revised and enabled by default. Packages which use GDB as a debugging
5454 engine behind a UI or another front end are encouraged to switch to
5455 using the GDB/MI interface, instead of the old annotations interface
5456 which is now deprecated.
5458 * Support for debugging Pascal programs.
5460 GDB now includes support for debugging Pascal programs. The following
5461 main features are supported:
5463 - Pascal-specific data types such as sets;
5465 - automatic recognition of Pascal sources based on file-name
5468 - Pascal-style display of data types, variables, and functions;
5470 - a Pascal expression parser.
5472 However, some important features are not yet supported.
5474 - Pascal string operations are not supported at all;
5476 - there are some problems with boolean types;
5478 - Pascal type hexadecimal constants are not supported
5479 because they conflict with the internal variables format;
5481 - support for Pascal objects and classes is not full yet;
5483 - unlike Pascal, GDB is case-sensitive for symbol names.
5485 * Changes in completion.
5487 Commands such as `shell', `run' and `set args', which pass arguments
5488 to inferior programs, now complete on file names, similar to what
5489 users expect at the shell prompt.
5491 Commands which accept locations, such as `disassemble', `print',
5492 `breakpoint', `until', etc. now complete on filenames as well as
5493 program symbols. Thus, if you type "break foob TAB", and the source
5494 files linked into the programs include `foobar.c', that file name will
5495 be one of the candidates for completion. However, file names are not
5496 considered for completion after you typed a colon that delimits a file
5497 name from a name of a function in that file, as in "break foo.c:bar".
5499 `set demangle-style' completes on available demangling styles.
5501 * New platform-independent commands:
5503 It is now possible to define a post-hook for a command as well as a
5504 hook that runs before the command. For more details, see the
5505 documentation of `hookpost' in the GDB manual.
5507 * Changes in GNU/Linux native debugging.
5509 Support for debugging multi-threaded programs has been completely
5510 revised for all platforms except m68k and sparc. You can now debug as
5511 many threads as your system allows you to have.
5513 Attach/detach is supported for multi-threaded programs.
5515 Support for SSE registers was added for x86. This doesn't work for
5516 multi-threaded programs though.
5518 * Changes in MIPS configurations.
5520 Multi-arch support is enabled for all MIPS configurations.
5522 GDB can now be built as native debugger on SGI Irix 6.x systems for
5523 debugging n32 executables. (Debugging 64-bit executables is not yet
5526 * Unified support for hardware watchpoints in all x86 configurations.
5528 Most (if not all) native x86 configurations support hardware-assisted
5529 breakpoints and watchpoints in a unified manner. This support
5530 implements debug register sharing between watchpoints, which allows to
5531 put a virtually infinite number of watchpoints on the same address,
5532 and also supports watching regions up to 16 bytes with several debug
5535 The new maintenance command `maintenance show-debug-regs' toggles
5536 debugging print-outs in functions that insert, remove, and test
5537 watchpoints and hardware breakpoints.
5539 * Changes in the DJGPP native configuration.
5541 New command ``info dos sysinfo'' displays assorted information about
5542 the CPU, OS, memory, and DPMI server.
5544 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
5545 display information about segment descriptors stored in GDT, LDT, and
5548 New commands ``info dos pde'' and ``info dos pte'' display entries
5549 from Page Directory and Page Tables (for now works with CWSDPMI only).
5550 New command ``info dos address-pte'' displays the Page Table entry for
5551 a given linear address.
5553 GDB can now pass command lines longer than 126 characters to the
5554 program being debugged (requires an update to the libdbg.a library
5555 which is part of the DJGPP development kit).
5557 DWARF2 debug info is now supported.
5559 It is now possible to `step' and `next' through calls to `longjmp'.
5561 * Changes in documentation.
5563 All GDB documentation was converted to GFDL, the GNU Free
5564 Documentation License.
5566 Tracepoints-related commands are now fully documented in the GDB
5569 TUI, the Text-mode User Interface, is now documented in the manual.
5571 Tracepoints-related commands are now fully documented in the GDB
5574 The "GDB Internals" manual now has an index. It also includes
5575 documentation of `ui_out' functions, GDB coding standards, x86
5576 hardware watchpoints, and memory region attributes.
5578 * GDB's version number moved to ``version.in''
5580 The Makefile variable VERSION has been replaced by the file
5581 ``version.in''. People creating GDB distributions should update the
5582 contents of this file.
5586 GUD support is now a standard part of the EMACS distribution.
5588 *** Changes in GDB 5.0:
5590 * Improved support for debugging FP programs on x86 targets
5592 Unified and much-improved support for debugging floating-point
5593 programs on all x86 targets. In particular, ``info float'' now
5594 displays the FP registers in the same format on all x86 targets, with
5595 greater level of detail.
5597 * Improvements and bugfixes in hardware-assisted watchpoints
5599 It is now possible to watch array elements, struct members, and
5600 bitfields with hardware-assisted watchpoints. Data-read watchpoints
5601 on x86 targets no longer erroneously trigger when the address is
5604 * Improvements in the native DJGPP version of GDB
5606 The distribution now includes all the scripts and auxiliary files
5607 necessary to build the native DJGPP version on MS-DOS/MS-Windows
5608 machines ``out of the box''.
5610 The DJGPP version can now debug programs that use signals. It is
5611 possible to catch signals that happened in the debuggee, deliver
5612 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
5613 would kill the program being debugged.) Programs that hook hardware
5614 interrupts (keyboard, timer, etc.) can also be debugged.
5616 It is now possible to debug DJGPP programs that redirect their
5617 standard handles or switch them to raw (as opposed to cooked) mode, or
5618 even close them. The command ``run < foo > bar'' works as expected,
5619 and ``info terminal'' reports useful information about the debuggee's
5620 terminal, including raw/cooked mode, redirection, etc.
5622 The DJGPP version now uses termios functions for console I/O, which
5623 enables debugging graphics programs. Interrupting GDB with Ctrl-C
5626 DOS-style file names with drive letters are now fully supported by
5629 It is now possible to debug DJGPP programs that switch their working
5630 directory. It is also possible to rerun the debuggee any number of
5631 times without restarting GDB; thus, you can use the same setup,
5632 breakpoints, etc. for many debugging sessions.
5634 * New native configurations
5636 ARM GNU/Linux arm*-*-linux*
5637 PowerPC GNU/Linux powerpc-*-linux*
5641 Motorola MCore mcore-*-*
5642 x86 VxWorks i[3456]86-*-vxworks*
5643 PowerPC VxWorks powerpc-*-vxworks*
5644 TI TMS320C80 tic80-*-*
5646 * OBSOLETE configurations
5648 Altos 3068 m68*-altos-*
5649 Convex c1-*-*, c2-*-*
5651 ARM RISCix arm-*-* (as host)
5654 Configurations that have been declared obsolete will be commented out,
5655 but the code will be left in place. If there is no activity to revive
5656 these configurations before the next release of GDB, the sources will
5657 be permanently REMOVED.
5659 * Gould support removed
5661 Support for the Gould PowerNode and NP1 has been removed.
5663 * New features for SVR4
5665 On SVR4 native platforms (such as Solaris), if you attach to a process
5666 without first loading a symbol file, GDB will now attempt to locate and
5667 load symbols from the running process's executable file.
5669 * Many C++ enhancements
5671 C++ support has been greatly improved. Overload resolution now works properly
5672 in almost all cases. RTTI support is on the way.
5674 * Remote targets can connect to a sub-program
5676 A popen(3) style serial-device has been added. This device starts a
5677 sub-process (such as a stand-alone simulator) and then communicates
5678 with that. The sub-program to run is specified using the syntax
5679 ``|<program> <args>'' vis:
5681 (gdb) set remotedebug 1
5682 (gdb) target extended-remote |mn10300-elf-sim program-args
5684 * MIPS 64 remote protocol
5686 A long standing bug in the mips64 remote protocol where by GDB
5687 expected certain 32 bit registers (ex SR) to be transfered as 32
5688 instead of 64 bits has been fixed.
5690 The command ``set remote-mips64-transfers-32bit-regs on'' has been
5691 added to provide backward compatibility with older versions of GDB.
5693 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
5695 The command ``set remotebinarydownload'' command has been replaced by
5696 ``set remote X-packet''. Other commands in ``set remote'' family
5697 include ``set remote P-packet''.
5699 * Breakpoint commands accept ranges.
5701 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
5702 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
5703 ``tracepoint passcount'' also accepts a range of tracepoints.
5705 * ``apropos'' command added.
5707 The ``apropos'' command searches through command names and
5708 documentation strings, printing out matches, making it much easier to
5709 try to find a command that does what you are looking for.
5713 A new machine oriented interface (MI) has been added to GDB. This
5714 interface is designed for debug environments running GDB as a separate
5715 process. This is part of the long term libGDB project. See the
5716 "GDB/MI" chapter of the GDB manual for further information. It can be
5717 enabled by configuring with:
5719 .../configure --enable-gdbmi
5721 *** Changes in GDB-4.18:
5723 * New native configurations
5725 HP-UX 10.20 hppa*-*-hpux10.20
5726 HP-UX 11.x hppa*-*-hpux11.0*
5727 M68K GNU/Linux m68*-*-linux*
5731 Fujitsu FR30 fr30-*-elf*
5732 Intel StrongARM strongarm-*-*
5733 Mitsubishi D30V d30v-*-*
5735 * OBSOLETE configurations
5737 Gould PowerNode, NP1 np1-*-*, pn-*-*
5739 Configurations that have been declared obsolete will be commented out,
5740 but the code will be left in place. If there is no activity to revive
5741 these configurations before the next release of GDB, the sources will
5742 be permanently REMOVED.
5746 As a compatibility experiment, GDB's source files buildsym.h and
5747 buildsym.c have been converted to pure standard C, no longer
5748 containing any K&R compatibility code. We believe that all systems in
5749 use today either come with a standard C compiler, or have a GCC port
5750 available. If this is not true, please report the affected
5751 configuration to bug-gdb@gnu.org immediately. See the README file for
5752 information about getting a standard C compiler if you don't have one
5757 GDB now uses readline 2.2.
5759 * set extension-language
5761 You can now control the mapping between filename extensions and source
5762 languages by using the `set extension-language' command. For instance,
5763 you can ask GDB to treat .c files as C++ by saying
5764 set extension-language .c c++
5765 The command `info extensions' lists all of the recognized extensions
5766 and their associated languages.
5768 * Setting processor type for PowerPC and RS/6000
5770 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
5771 you can use the `set processor' command to specify what variant of the
5772 PowerPC family you are debugging. The command
5776 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
5777 following PowerPC and RS6000 variants:
5779 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
5780 rs6000 IBM RS6000 ("POWER") architecture, user-level view
5782 403GC IBM PowerPC 403GC
5783 505 Motorola PowerPC 505
5784 860 Motorola PowerPC 860 or 850
5785 601 Motorola PowerPC 601
5786 602 Motorola PowerPC 602
5787 603 Motorola/IBM PowerPC 603 or 603e
5788 604 Motorola PowerPC 604 or 604e
5789 750 Motorola/IBM PowerPC 750 or 750
5791 At the moment, this command just tells GDB what to name the
5792 special-purpose processor registers. Since almost all the affected
5793 registers are inaccessible to user-level programs, this command is
5794 only useful for remote debugging in its present form.
5798 Thanks to a major code donation from Hewlett-Packard, GDB now has much
5799 more extensive support for HP-UX. Added features include shared
5800 library support, kernel threads and hardware watchpoints for 11.00,
5801 support for HP's ANSI C and C++ compilers, and a compatibility mode
5802 for xdb and dbx commands.
5806 HP's donation includes the new concept of catchpoints, which is a
5807 generalization of the old catch command. On HP-UX, it is now possible
5808 to catch exec, fork, and vfork, as well as library loading.
5810 This means that the existing catch command has changed; its first
5811 argument now specifies the type of catch to be set up. See the
5812 output of "help catch" for a list of catchpoint types.
5814 * Debugging across forks
5816 On HP-UX, you can choose which process to debug when a fork() happens
5821 HP has donated a curses-based terminal user interface (TUI). To get
5822 it, build with --enable-tui. Although this can be enabled for any
5823 configuration, at present it only works for native HP debugging.
5825 * GDB remote protocol additions
5827 A new protocol packet 'X' that writes binary data is now available.
5828 Default behavior is to try 'X', then drop back to 'M' if the stub
5829 fails to respond. The settable variable `remotebinarydownload'
5830 allows explicit control over the use of 'X'.
5832 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
5833 full 64-bit address. The command
5835 set remoteaddresssize 32
5837 can be used to revert to the old behaviour. For existing remote stubs
5838 the change should not be noticed, as the additional address information
5841 In order to assist in debugging stubs, you may use the maintenance
5842 command `packet' to send any text string to the stub. For instance,
5844 maint packet heythere
5846 sends the packet "$heythere#<checksum>". Note that it is very easy to
5847 disrupt a debugging session by sending the wrong packet at the wrong
5850 The compare-sections command allows you to compare section data on the
5851 target to what is in the executable file without uploading or
5852 downloading, by comparing CRC checksums.
5854 * Tracing can collect general expressions
5856 You may now collect general expressions at tracepoints. This requires
5857 further additions to the target-side stub; see tracepoint.c and
5858 doc/agentexpr.texi for further details.
5860 * mask-address variable for Mips
5862 For Mips targets, you may control the zeroing of the upper 32 bits of
5863 a 64-bit address by entering `set mask-address on'. This is mainly
5864 of interest to users of embedded R4xxx and R5xxx processors.
5866 * Higher serial baud rates
5868 GDB's serial code now allows you to specify baud rates 57600, 115200,
5869 230400, and 460800 baud. (Note that your host system may not be able
5870 to achieve all of these rates.)
5874 The i960 configuration now includes an initial implementation of a
5875 builtin simulator, contributed by Jim Wilson.
5878 *** Changes in GDB-4.17:
5880 * New native configurations
5882 Alpha GNU/Linux alpha*-*-linux*
5883 Unixware 2.x i[3456]86-unixware2*
5884 Irix 6.x mips*-sgi-irix6*
5885 PowerPC GNU/Linux powerpc-*-linux*
5886 PowerPC Solaris powerpcle-*-solaris*
5887 Sparc GNU/Linux sparc-*-linux*
5888 Motorola sysV68 R3V7.1 m68k-motorola-sysv
5892 Argonaut Risc Chip (ARC) arc-*-*
5893 Hitachi H8/300S h8300*-*-*
5894 Matsushita MN10200 w/simulator mn10200-*-*
5895 Matsushita MN10300 w/simulator mn10300-*-*
5896 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
5897 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
5898 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
5899 Mitsubishi D10V w/simulator d10v-*-*
5900 Mitsubishi M32R/D w/simulator m32r-*-elf*
5901 Tsqware Sparclet sparclet-*-*
5902 NEC V850 w/simulator v850-*-*
5904 * New debugging protocols
5906 ARM with RDI protocol arm*-*-*
5907 M68K with dBUG monitor m68*-*-{aout,coff,elf}
5908 DDB and LSI variants of PMON protocol mips*-*-*
5909 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
5910 PowerPC with SDS protocol powerpc{,le}-*-eabi
5911 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
5915 All configurations can now understand and use the DWARF 2 debugging
5916 format. The choice is automatic, if the symbol file contains DWARF 2
5921 GDB now includes basic Java language support. This support is
5922 only useful with Java compilers that produce native machine code.
5924 * solib-absolute-prefix and solib-search-path
5926 For SunOS and SVR4 shared libraries, you may now set the prefix for
5927 loading absolute shared library symbol files, and the search path for
5928 locating non-absolute shared library symbol files.
5930 * Live range splitting
5932 GDB can now effectively debug code for which GCC has performed live
5933 range splitting as part of its optimization. See gdb/doc/LRS for
5934 more details on the expected format of the stabs information.
5938 GDB's support for the GNU Hurd, including thread debugging, has been
5939 updated to work with current versions of the Hurd.
5943 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
5944 instruction set. ARM GDB automatically detects when Thumb
5945 instructions are in use, and adjusts disassembly and backtracing
5950 GDB's MIPS target configurations now handle the MIP16 16-bit
5955 GDB now includes support for overlays; if an executable has been
5956 linked such that multiple sections are based at the same address, GDB
5957 will decide which section to use for symbolic info. You can choose to
5958 control the decision manually, using overlay commands, or implement
5959 additional target-side support and use "overlay load-target" to bring
5960 in the overlay mapping. Do "help overlay" for more detail.
5964 The command "info symbol <address>" displays information about
5965 the symbol at the specified address.
5969 The standard remote protocol now includes an extension that allows
5970 asynchronous collection and display of trace data. This requires
5971 extensive support in the target-side debugging stub. Tracing mode
5972 includes a new interaction mode in GDB and new commands: see the
5973 file tracepoint.c for more details.
5977 Configurations for embedded MIPS now include a simulator contributed
5978 by Cygnus Solutions. The simulator supports the instruction sets
5979 of most MIPS variants.
5983 Sparc configurations may now include the ERC32 simulator contributed
5984 by the European Space Agency. The simulator is not built into
5985 Sparc targets by default; configure with --enable-sim to include it.
5989 For target configurations that may include multiple variants of a
5990 basic architecture (such as MIPS and SH), you may now set the
5991 architecture explicitly. "set arch" sets, "info arch" lists
5992 the possible architectures.
5994 *** Changes in GDB-4.16:
5996 * New native configurations
5998 Windows 95, x86 Windows NT i[345]86-*-cygwin32
5999 M68K NetBSD m68k-*-netbsd*
6000 PowerPC AIX 4.x powerpc-*-aix*
6001 PowerPC MacOS powerpc-*-macos*
6002 PowerPC Windows NT powerpcle-*-cygwin32
6003 RS/6000 AIX 4.x rs6000-*-aix4*
6007 ARM with RDP protocol arm-*-*
6008 I960 with MON960 i960-*-coff
6009 MIPS VxWorks mips*-*-vxworks*
6010 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
6011 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
6013 Matra Sparclet sparclet-*-*
6017 The powerpc-eabi configuration now includes the PSIM simulator,
6018 contributed by Andrew Cagney, with assistance from Mike Meissner.
6019 PSIM is a very elaborate model of the PowerPC, including not only
6020 basic instruction set execution, but also details of execution unit
6021 performance and I/O hardware. See sim/ppc/README for more details.
6025 GDB now works with Solaris 2.5.
6027 * Windows 95/NT native
6029 GDB will now work as a native debugger on Windows 95 and Windows NT.
6030 To build it from source, you must use the "gnu-win32" environment,
6031 which uses a DLL to emulate enough of Unix to run the GNU tools.
6032 Further information, binaries, and sources are available at
6033 ftp.cygnus.com, under pub/gnu-win32.
6035 * dont-repeat command
6037 If a user-defined command includes the command `dont-repeat', then the
6038 command will not be repeated if the user just types return. This is
6039 useful if the command is time-consuming to run, so that accidental
6040 extra keystrokes don't run the same command many times.
6042 * Send break instead of ^C
6044 The standard remote protocol now includes an option to send a break
6045 rather than a ^C to the target in order to interrupt it. By default,
6046 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
6048 * Remote protocol timeout
6050 The standard remote protocol includes a new variable `remotetimeout'
6051 that allows you to set the number of seconds before GDB gives up trying
6052 to read from the target. The default value is 2.
6054 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
6056 By default GDB will automatically keep track of objects as they are
6057 loaded and unloaded by the dynamic linker. By using the command `set
6058 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
6059 when shared library events occur, thus allowing you to set breakpoints
6060 in shared libraries which are explicitly loaded by the inferior.
6062 Note this feature does not work on hpux8. On hpux9 you must link
6063 /usr/lib/end.o into your program. This feature should work
6064 automatically on hpux10.
6066 * Irix 5.x hardware watchpoint support
6068 Irix 5 configurations now support the use of hardware watchpoints.
6070 * Mips protocol "SYN garbage limit"
6072 When debugging a Mips target using the `target mips' protocol, you
6073 may set the number of characters that GDB will ignore by setting
6074 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
6075 every character. The default value is 1050.
6077 * Recording and replaying remote debug sessions
6079 If you set `remotelogfile' to the name of a file, gdb will write to it
6080 a recording of a remote debug session. This recording may then be
6081 replayed back to gdb using "gdbreplay". See gdbserver/README for
6082 details. This is useful when you have a problem with GDB while doing
6083 remote debugging; you can make a recording of the session and send it
6084 to someone else, who can then recreate the problem.
6086 * Speedups for remote debugging
6088 GDB includes speedups for downloading and stepping MIPS systems using
6089 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
6090 and more efficient S-record downloading.
6092 * Memory use reductions and statistics collection
6094 GDB now uses less memory and reports statistics about memory usage.
6095 Try the `maint print statistics' command, for example.
6097 *** Changes in GDB-4.15:
6099 * Psymtabs for XCOFF
6101 The symbol reader for AIX GDB now uses partial symbol tables. This
6102 can greatly improve startup time, especially for large executables.
6104 * Remote targets use caching
6106 Remote targets now use a data cache to speed up communication with the
6107 remote side. The data cache could lead to incorrect results because
6108 it doesn't know about volatile variables, thus making it impossible to
6109 debug targets which use memory mapped I/O devices. `set remotecache
6110 off' turns the the data cache off.
6112 * Remote targets may have threads
6114 The standard remote protocol now includes support for multiple threads
6115 in the target system, using new protocol commands 'H' and 'T'. See
6116 gdb/remote.c for details.
6120 If GDB is configured with `--enable-netrom', then it will include
6121 support for the NetROM ROM emulator from XLNT Designs. The NetROM
6122 acts as though it is a bank of ROM on the target board, but you can
6123 write into it over the network. GDB's support consists only of
6124 support for fast loading into the emulated ROM; to debug, you must use
6125 another protocol, such as standard remote protocol. The usual
6126 sequence is something like
6128 target nrom <netrom-hostname>
6130 target remote <netrom-hostname>:1235
6134 GDB now includes support for the Apple Macintosh, as a host only. It
6135 may be run as either an MPW tool or as a standalone application, and
6136 it can debug through the serial port. All the usual GDB commands are
6137 available, but to the target command, you must supply "serial" as the
6138 device type instead of "/dev/ttyXX". See mpw-README in the main
6139 directory for more information on how to build. The MPW configuration
6140 scripts */mpw-config.in support only a few targets, and only the
6141 mips-idt-ecoff target has been tested.
6145 GDB configuration now uses autoconf. This is not user-visible,
6146 but does simplify configuration and building.
6150 GDB now supports hpux10.
6152 *** Changes in GDB-4.14:
6154 * New native configurations
6156 x86 FreeBSD i[345]86-*-freebsd
6157 x86 NetBSD i[345]86-*-netbsd
6158 NS32k NetBSD ns32k-*-netbsd
6159 Sparc NetBSD sparc-*-netbsd
6163 A29K VxWorks a29k-*-vxworks
6164 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
6165 CPU32 EST-300 emulator m68*-*-est*
6166 PowerPC ELF powerpc-*-elf
6169 * Alpha OSF/1 support for procfs
6171 GDB now supports procfs under OSF/1-2.x and higher, which makes it
6172 possible to attach to running processes. As the mounting of the /proc
6173 filesystem is optional on the Alpha, GDB automatically determines
6174 the availability of /proc during startup. This can lead to problems
6175 if /proc is unmounted after GDB has been started.
6177 * Arguments to user-defined commands
6179 User commands may accept up to 10 arguments separated by whitespace.
6180 Arguments are accessed within the user command via $arg0..$arg9. A
6183 print $arg0 + $arg1 + $arg2
6185 To execute the command use:
6188 Defines the command "adder" which prints the sum of its three arguments.
6189 Note the arguments are text substitutions, so they may reference variables,
6190 use complex expressions, or even perform inferior function calls.
6192 * New `if' and `while' commands
6194 This makes it possible to write more sophisticated user-defined
6195 commands. Both commands take a single argument, which is the
6196 expression to evaluate, and must be followed by the commands to
6197 execute, one per line, if the expression is nonzero, the list being
6198 terminated by the word `end'. The `if' command list may include an
6199 `else' word, which causes the following commands to be executed only
6200 if the expression is zero.
6202 * Fortran source language mode
6204 GDB now includes partial support for Fortran 77. It will recognize
6205 Fortran programs and can evaluate a subset of Fortran expressions, but
6206 variables and functions may not be handled correctly. GDB will work
6207 with G77, but does not yet know much about symbols emitted by other
6210 * Better HPUX support
6212 Most debugging facilities now work on dynamic executables for HPPAs
6213 running hpux9 or later. You can attach to running dynamically linked
6214 processes, but by default the dynamic libraries will be read-only, so
6215 for instance you won't be able to put breakpoints in them. To change
6216 that behavior do the following before running the program:
6222 This will cause the libraries to be mapped private and read-write.
6223 To revert to the normal behavior, do this:
6229 You cannot set breakpoints or examine data in the library until after
6230 the library is loaded if the function/data symbols do not have
6233 GDB can now also read debug symbols produced by the HP C compiler on
6234 HPPAs (sorry, no C++, Fortran or 68k support).
6236 * Target byte order now dynamically selectable
6238 You can choose which byte order to use with a target system, via the
6239 commands "set endian big" and "set endian little", and you can see the
6240 current setting by using "show endian". You can also give the command
6241 "set endian auto", in which case GDB will use the byte order
6242 associated with the executable. Currently, only embedded MIPS
6243 configurations support dynamic selection of target byte order.
6245 * New DOS host serial code
6247 This version uses DPMI interrupts to handle buffered I/O, so you
6248 no longer need to run asynctsr when debugging boards connected to
6251 *** Changes in GDB-4.13:
6253 * New "complete" command
6255 This lists all the possible completions for the rest of the line, if it
6256 were to be given as a command itself. This is intended for use by emacs.
6258 * Trailing space optional in prompt
6260 "set prompt" no longer adds a space for you after the prompt you set. This
6261 allows you to set a prompt which ends in a space or one that does not.
6263 * Breakpoint hit counts
6265 "info break" now displays a count of the number of times the breakpoint
6266 has been hit. This is especially useful in conjunction with "ignore"; you
6267 can ignore a large number of breakpoint hits, look at the breakpoint info
6268 to see how many times the breakpoint was hit, then run again, ignoring one
6269 less than that number, and this will get you quickly to the last hit of
6272 * Ability to stop printing at NULL character
6274 "set print null-stop" will cause GDB to stop printing the characters of
6275 an array when the first NULL is encountered. This is useful when large
6276 arrays actually contain only short strings.
6278 * Shared library breakpoints
6280 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
6281 breakpoints in shared libraries before the executable is run.
6283 * Hardware watchpoints
6285 There is a new hardware breakpoint for the watch command for sparclite
6286 targets. See gdb/sparclite/hw_breakpoint.note.
6288 Hardware watchpoints are also now supported under GNU/Linux.
6292 Annotations have been added. These are for use with graphical interfaces,
6293 and are still experimental. Currently only gdba.el uses these.
6295 * Improved Irix 5 support
6297 GDB now works properly with Irix 5.2.
6299 * Improved HPPA support
6301 GDB now works properly with the latest GCC and GAS.
6303 * New native configurations
6305 Sequent PTX4 i[34]86-sequent-ptx4
6306 HPPA running OSF/1 hppa*-*-osf*
6307 Atari TT running SVR4 m68*-*-sysv4*
6308 RS/6000 LynxOS rs6000-*-lynxos*
6312 OS/9000 i[34]86-*-os9k
6313 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
6316 * Hitachi SH7000 and E7000-PC ICE support
6318 There is now support for communicating with the Hitachi E7000-PC ICE.
6319 This is available automatically when GDB is configured for the SH.
6323 As usual, a variety of small fixes and improvements, both generic
6324 and configuration-specific. See the ChangeLog for more detail.
6326 *** Changes in GDB-4.12:
6328 * Irix 5 is now supported
6332 GDB-4.12 on the HPPA has a number of changes which make it unable
6333 to debug the output from the currently released versions of GCC and
6334 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
6335 of GCC and GAS, versions of these tools designed to work with GDB-4.12
6336 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
6339 *** Changes in GDB-4.11:
6341 * User visible changes:
6345 The "set remotedebug" option is now consistent between the mips remote
6346 target, remote targets using the gdb-specific protocol, UDI (AMD's
6347 debug protocol for the 29k) and the 88k bug monitor. It is now an
6348 integer specifying a debug level (normally 0 or 1, but 2 means more
6349 debugging info for the mips target).
6351 * DEC Alpha native support
6353 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
6354 debug info, but GDB works fairly well with the DEC compiler and should
6355 work with a future GCC release. See the README file for a few
6356 Alpha-specific notes.
6358 * Preliminary thread implementation
6360 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
6362 * LynxOS native and target support for 386
6364 This release has been hosted on LynxOS 2.2, and also can be configured
6365 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
6368 * Improvements in C++ mangling/demangling.
6370 This release has much better g++ debugging, specifically in name
6371 mangling/demangling, virtual function calls, print virtual table,
6372 call methods, ...etc.
6374 *** Changes in GDB-4.10:
6376 * User visible changes:
6378 Remote debugging using the GDB-specific (`target remote') protocol now
6379 supports the `load' command. This is only useful if you have some
6380 other way of getting the stub to the target system, and you can put it
6381 somewhere in memory where it won't get clobbered by the download.
6383 Filename completion now works.
6385 When run under emacs mode, the "info line" command now causes the
6386 arrow to point to the line specified. Also, "info line" prints
6387 addresses in symbolic form (as well as hex).
6389 All vxworks based targets now support a user settable option, called
6390 vxworks-timeout. This option represents the number of seconds gdb
6391 should wait for responses to rpc's. You might want to use this if
6392 your vxworks target is, perhaps, a slow software simulator or happens
6393 to be on the far side of a thin network line.
6397 This release contains support for using a DEC alpha as a GDB host for
6398 cross debugging. Native alpha debugging is not supported yet.
6401 *** Changes in GDB-4.9:
6405 This is the first GDB release which is accompanied by a matching testsuite.
6406 The testsuite requires installation of dejagnu, which should be available
6407 via ftp from most sites that carry GNU software.
6411 'Cfront' style demangling has had its name changed to 'ARM' style, to
6412 emphasize that it was written from the specifications in the C++ Annotated
6413 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
6414 disclaimers, it still generated too much confusion with users attempting to
6415 use gdb with AT&T cfront.
6419 GDB now uses a standard remote interface to a simulator library.
6420 So far, the library contains simulators for the Zilog Z8001/2, the
6421 Hitachi H8/300, H8/500 and Super-H.
6423 * New targets supported
6425 H8/300 simulator h8300-hitachi-hms or h8300hms
6426 H8/500 simulator h8500-hitachi-hms or h8500hms
6427 SH simulator sh-hitachi-hms or sh
6428 Z8000 simulator z8k-zilog-none or z8ksim
6429 IDT MIPS board over serial line mips-idt-ecoff
6431 Cross-debugging to GO32 targets is supported. It requires a custom
6432 version of the i386-stub.c module which is integrated with the
6433 GO32 memory extender.
6435 * New remote protocols
6437 MIPS remote debugging protocol.
6439 * New source languages supported
6441 This version includes preliminary support for Chill, a Pascal like language
6442 used by telecommunications companies. Chill support is also being integrated
6443 into the GNU compiler, but we don't know when it will be publically available.
6446 *** Changes in GDB-4.8:
6448 * HP Precision Architecture supported
6450 GDB now supports HP PA-RISC machines running HPUX. A preliminary
6451 version of this support was available as a set of patches from the
6452 University of Utah. GDB does not support debugging of programs
6453 compiled with the HP compiler, because HP will not document their file
6454 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
6455 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
6457 Many problems in the preliminary version have been fixed.
6459 * Faster and better demangling
6461 We have improved template demangling and fixed numerous bugs in the GNU style
6462 demangler. It can now handle type modifiers such as `static' or `const'. Wide
6463 character types (wchar_t) are now supported. Demangling of each symbol is now
6464 only done once, and is cached when the symbol table for a file is read in.
6465 This results in a small increase in memory usage for C programs, a moderate
6466 increase in memory usage for C++ programs, and a fantastic speedup in
6469 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
6470 from the specifications in the Annotated Reference Manual, which AT&T's
6471 compiler does not actually implement.
6473 * G++ multiple inheritance compiler problem
6475 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
6476 inheritance lattices was reworked to properly discover ambiguities. We
6477 recently found an example which causes this new algorithm to fail in a
6478 very subtle way, producing bad debug information for those classes.
6479 The file 'gcc.patch' (in this directory) can be applied to gcc to
6480 circumvent the problem. A future GCC release will contain a complete
6483 The previous G++ debug info problem (mentioned below for the gdb-4.7
6484 release) is fixed in gcc version 2.3.2.
6486 * Improved configure script
6488 The `configure' script will now attempt to guess your system type if
6489 you don't supply a host system type. The old scheme of supplying a
6490 host system triplet is preferable over using this. All the magic is
6491 done in the new `config.guess' script. Examine it for details.
6493 We have also brought our configure script much more in line with the FSF's
6494 version. It now supports the --with-xxx options. In particular,
6495 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
6496 The resulting GDB will not be able to read arbitrary object file formats --
6497 only the format ``expected'' to be used on the configured target system.
6498 We hope to make this the default in a future release.
6500 * Documentation improvements
6502 There's new internal documentation on how to modify GDB, and how to
6503 produce clean changes to the code. We implore people to read it
6504 before submitting changes.
6506 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
6507 M4 macros. The new texinfo.tex is provided in this release. Pre-built
6508 `info' files are also provided. To build `info' files from scratch,
6509 you will need the latest `makeinfo' release, which will be available in
6510 a future texinfo-X.Y release.
6512 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
6513 We're not sure exactly which versions have this problem, but it has
6514 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
6515 or better. If that isn't possible, there is a patch in
6516 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
6517 around this problem.
6521 GDB now supports array constants that can be used in expressions typed in by
6522 the user. The syntax is `{element, element, ...}'. Ie: you can now type
6523 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
6526 The new directory `gdb/sparclite' contains a program that demonstrates
6527 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
6529 * New native hosts supported
6531 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
6532 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
6534 * New targets supported
6536 AMD 29k family via UDI a29k-amd-udi or udi29k
6538 * New file formats supported
6540 BFD now supports reading HP/PA-RISC executables (SOM file format?),
6541 HPUX core files, and SCO 3.2v2 core files.
6545 Attaching to processes now works again; thanks for the many bug reports.
6547 We have also stomped on a bunch of core dumps caused by
6548 printf_filtered("%s") problems.
6550 We eliminated a copyright problem on the rpc and ptrace header files
6551 for VxWorks, which was discovered at the last minute during the 4.7
6552 release. You should now be able to build a VxWorks GDB.
6554 You can now interrupt gdb while an attached process is running. This
6555 will cause the attached process to stop, and give control back to GDB.
6557 We fixed problems caused by using too many file descriptors
6558 for reading symbols from object files and libraries. This was
6559 especially a problem for programs that used many (~100) shared
6562 The `step' command now only enters a subroutine if there is line number
6563 information for the subroutine. Otherwise it acts like the `next'
6564 command. Previously, `step' would enter subroutines if there was
6565 any debugging information about the routine. This avoids problems
6566 when using `cc -g1' on MIPS machines.
6568 * Internal improvements
6570 GDB's internal interfaces have been improved to make it easier to support
6571 debugging of multiple languages in the future.
6573 GDB now uses a common structure for symbol information internally.
6574 Minimal symbols (derived from linkage symbols in object files), partial
6575 symbols (from a quick scan of debug information), and full symbols
6576 contain a common subset of information, making it easier to write
6577 shared code that handles any of them.
6579 * New command line options
6581 We now accept --silent as an alias for --quiet.
6585 The memory-mapped-malloc library is now licensed under the GNU Library
6586 General Public License.
6588 *** Changes in GDB-4.7:
6590 * Host/native/target split
6592 GDB has had some major internal surgery to untangle the support for
6593 hosts and remote targets. Now, when you configure GDB for a remote
6594 target, it will no longer load in all of the support for debugging
6595 local programs on the host. When fully completed and tested, this will
6596 ensure that arbitrary host/target combinations are possible.
6598 The primary conceptual shift is to separate the non-portable code in
6599 GDB into three categories. Host specific code is required any time GDB
6600 is compiled on that host, regardless of the target. Target specific
6601 code relates to the peculiarities of the target, but can be compiled on
6602 any host. Native specific code is everything else: it can only be
6603 built when the host and target are the same system. Child process
6604 handling and core file support are two common `native' examples.
6606 GDB's use of /proc for controlling Unix child processes is now cleaner.
6607 It has been split out into a single module under the `target_ops' vector,
6608 plus two native-dependent functions for each system that uses /proc.
6610 * New hosts supported
6612 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
6613 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6614 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
6616 * New targets supported
6618 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
6619 68030 and CPU32 m68030-*-*, m68332-*-*
6621 * New native hosts supported
6623 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
6624 (386bsd is not well tested yet)
6625 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
6627 * New file formats supported
6629 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
6630 supports reading of `a.out.adobe' object files, which are an a.out
6631 format extended with minimal information about multiple sections.
6635 `show copying' is the same as the old `info copying'.
6636 `show warranty' is the same as `info warrantee'.
6637 These were renamed for consistency. The old commands continue to work.
6639 `info handle' is a new alias for `info signals'.
6641 You can now define pre-command hooks, which attach arbitrary command
6642 scripts to any command. The commands in the hook will be executed
6643 prior to the user's command. You can also create a hook which will be
6644 executed whenever the program stops. See gdb.texinfo.
6648 We now deal with Cfront style name mangling, and can even extract type
6649 info from mangled symbols. GDB can automatically figure out which
6650 symbol mangling style your C++ compiler uses.
6652 Calling of methods and virtual functions has been improved as well.
6656 The crash that occured when debugging Sun Ansi-C compiled binaries is
6657 fixed. This was due to mishandling of the extra N_SO stabs output
6660 We also finally got Ultrix 4.2 running in house, and fixed core file
6661 support, with help from a dozen people on the net.
6663 John M. Farrell discovered that the reason that single-stepping was so
6664 slow on all of the Mips based platforms (primarily SGI and DEC) was
6665 that we were trying to demangle and lookup a symbol used for internal
6666 purposes on every instruction that was being stepped through. Changing
6667 the name of that symbol so that it couldn't be mistaken for a C++
6668 mangled symbol sped things up a great deal.
6670 Rich Pixley sped up symbol lookups in general by getting much smarter
6671 about when C++ symbol mangling is necessary. This should make symbol
6672 completion (TAB on the command line) much faster. It's not as fast as
6673 we'd like, but it's significantly faster than gdb-4.6.
6677 A new user controllable variable 'call_scratch_address' can
6678 specify the location of a scratch area to be used when GDB
6679 calls a function in the target. This is necessary because the
6680 usual method of putting the scratch area on the stack does not work
6681 in systems that have separate instruction and data spaces.
6683 We integrated changes to support the 29k UDI (Universal Debugger
6684 Interface), but discovered at the last minute that we didn't have all
6685 of the appropriate copyright paperwork. We are working with AMD to
6686 resolve this, and hope to have it available soon.
6690 We have sped up the remote serial line protocol, especially for targets
6691 with lots of registers. It now supports a new `expedited status' ('T')
6692 message which can be used in place of the existing 'S' status message.
6693 This allows the remote stub to send only the registers that GDB
6694 needs to make a quick decision about single-stepping or conditional
6695 breakpoints, eliminating the need to fetch the entire register set for
6696 each instruction being stepped through.
6698 The GDB remote serial protocol now implements a write-through cache for
6699 registers, only re-reading the registers if the target has run.
6701 There is also a new remote serial stub for SPARC processors. You can
6702 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
6703 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
6704 processor with a serial port.
6708 Configure.in files have become much easier to read and modify. A new
6709 `table driven' format makes it more obvious what configurations are
6710 supported, and what files each one uses.
6714 There is a new opcodes library which will eventually contain all of the
6715 disassembly routines and opcode tables. At present, it only contains
6716 Sparc and Z8000 routines. This will allow the assembler, debugger, and
6717 disassembler (binutils/objdump) to share these routines.
6719 The libiberty library is now copylefted under the GNU Library General
6720 Public License. This allows more liberal use, and was done so libg++
6721 can use it. This makes no difference to GDB, since the Library License
6722 grants all the rights from the General Public License.
6726 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
6727 reference to the stabs symbol info used by the debugger. It is (as far
6728 as we know) the only published document on this fascinating topic. We
6729 encourage you to read it, compare it to the stabs information on your
6730 system, and send improvements on the document in general (to
6731 bug-gdb@prep.ai.mit.edu).
6733 And, of course, many bugs have been fixed.
6736 *** Changes in GDB-4.6:
6738 * Better support for C++ function names
6740 GDB now accepts as input the "demangled form" of C++ overloaded function
6741 names and member function names, and can do command completion on such names
6742 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
6743 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
6744 Make use of command completion, it is your friend.
6746 GDB also now accepts a variety of C++ mangled symbol formats. They are
6747 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
6748 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
6749 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
6750 for the list of formats.
6752 * G++ symbol mangling problem
6754 Recent versions of gcc have a bug in how they emit debugging information for
6755 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
6756 directory) can be applied to gcc to fix the problem. Alternatively, if you
6757 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
6758 usual symptom is difficulty with setting breakpoints on methods. GDB complains
6759 about the method being non-existent. (We believe that version 2.2.2 of GCC has
6762 * New 'maintenance' command
6764 All of the commands related to hacking GDB internals have been moved out of
6765 the main command set, and now live behind the 'maintenance' command. This
6766 can also be abbreviated as 'mt'. The following changes were made:
6768 dump-me -> maintenance dump-me
6769 info all-breakpoints -> maintenance info breakpoints
6770 printmsyms -> maintenance print msyms
6771 printobjfiles -> maintenance print objfiles
6772 printpsyms -> maintenance print psymbols
6773 printsyms -> maintenance print symbols
6775 The following commands are new:
6777 maintenance demangle Call internal GDB demangler routine to
6778 demangle a C++ link name and prints the result.
6779 maintenance print type Print a type chain for a given symbol
6781 * Change to .gdbinit file processing
6783 We now read the $HOME/.gdbinit file before processing the argv arguments
6784 (e.g. reading symbol files or core files). This allows global parameters to
6785 be set, which will apply during the symbol reading. The ./.gdbinit is still
6786 read after argv processing.
6788 * New hosts supported
6790 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
6792 GNU/Linux support i386-unknown-linux or linux
6794 We are also including code to support the HP/PA running BSD and HPUX. This
6795 is almost guaranteed not to work, as we didn't have time to test or build it
6796 for this release. We are including it so that the more adventurous (or
6797 masochistic) of you can play with it. We also had major problems with the
6798 fact that the compiler that we got from HP doesn't support the -g option.
6801 * New targets supported
6803 Hitachi H8/300 h8300-hitachi-hms or h8300hms
6805 * More smarts about finding #include files
6807 GDB now remembers the compilation directory for all include files, and for
6808 all files from which C is generated (like yacc and lex sources). This
6809 greatly improves GDB's ability to find yacc/lex sources, and include files,
6810 especially if you are debugging your program from a directory different from
6811 the one that contains your sources.
6813 We also fixed a bug which caused difficulty with listing and setting
6814 breakpoints in include files which contain C code. (In the past, you had to
6815 try twice in order to list an include file that you hadn't looked at before.)
6817 * Interesting infernals change
6819 GDB now deals with arbitrary numbers of sections, where the symbols for each
6820 section must be relocated relative to that section's landing place in the
6821 target's address space. This work was needed to support ELF with embedded
6822 stabs used by Solaris-2.0.
6824 * Bug fixes (of course!)
6826 There have been loads of fixes for the following things:
6827 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
6828 i960, stabs, DOS(GO32), procfs, etc...
6830 See the ChangeLog for details.
6832 *** Changes in GDB-4.5:
6834 * New machines supported (host and target)
6836 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
6838 SGI Irix-4.x mips-sgi-irix4 or iris4
6840 * New malloc package
6842 GDB now uses a new memory manager called mmalloc, based on gmalloc.
6843 Mmalloc is capable of handling mutiple heaps of memory. It is also
6844 capable of saving a heap to a file, and then mapping it back in later.
6845 This can be used to greatly speedup the startup of GDB by using a
6846 pre-parsed symbol table which lives in a mmalloc managed heap. For
6847 more details, please read mmalloc/mmalloc.texi.
6851 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
6852 'help info proc' for details.
6854 * MIPS ecoff symbol table format
6856 The code that reads MIPS symbol table format is now supported on all hosts.
6857 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
6860 * File name changes for MS-DOS
6862 Many files in the config directories have been renamed to make it easier to
6863 support GDB on MS-DOSe systems (which have very restrictive file name
6864 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
6865 environment) is close to working but has some remaining problems. Note
6866 that debugging of DOS programs is not supported, due to limitations
6867 in the ``operating system'', but it can be used to host cross-debugging.
6869 * Cross byte order fixes
6871 Many fixes have been made to support cross debugging of Sparc and MIPS
6872 targets from hosts whose byte order differs.
6874 * New -mapped and -readnow options
6876 If memory-mapped files are available on your system through the 'mmap'
6877 system call, you can use the -mapped option on the `file' or
6878 `symbol-file' commands to cause GDB to write the symbols from your
6879 program into a reusable file. If the program you are debugging is
6880 called `/path/fred', the mapped symbol file will be `./fred.syms'.
6881 Future GDB debugging sessions will notice the presence of this file,
6882 and will quickly map in symbol information from it, rather than reading
6883 the symbol table from the executable program. Using the '-mapped'
6884 option in a GDB `file' or `symbol-file' command has the same effect as
6885 starting GDB with the '-mapped' command-line option.
6887 You can cause GDB to read the entire symbol table immediately by using
6888 the '-readnow' option with any of the commands that load symbol table
6889 information (or on the GDB command line). This makes the command
6890 slower, but makes future operations faster.
6892 The -mapped and -readnow options are typically combined in order to
6893 build a `fred.syms' file that contains complete symbol information.
6894 A simple GDB invocation to do nothing but build a `.syms' file for future
6897 gdb -batch -nx -mapped -readnow programname
6899 The `.syms' file is specific to the host machine on which GDB is run.
6900 It holds an exact image of GDB's internal symbol table. It cannot be
6901 shared across multiple host platforms.
6903 * longjmp() handling
6905 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
6906 siglongjmp() without losing control. This feature has not yet been ported to
6907 all systems. It currently works on many 386 platforms, all MIPS-based
6908 platforms (SGI, DECstation, etc), and Sun3/4.
6912 Preliminary work has been put in to support the new Solaris OS from Sun. At
6913 this time, it can control and debug processes, but it is not capable of
6918 As always, many many bug fixes. The major areas were with g++, and mipsread.
6919 People using the MIPS-based platforms should experience fewer mysterious
6920 crashes and trashed symbol tables.
6922 *** Changes in GDB-4.4:
6924 * New machines supported (host and target)
6926 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6928 BSD Reno on Vax vax-dec-bsd
6929 Ultrix on Vax vax-dec-ultrix
6931 * New machines supported (target)
6933 AMD 29000 embedded, using EBMON a29k-none-none
6937 GDB continues to improve its handling of C++. `References' work better.
6938 The demangler has also been improved, and now deals with symbols mangled as
6939 per the Annotated C++ Reference Guide.
6941 GDB also now handles `stabs' symbol information embedded in MIPS
6942 `ecoff' symbol tables. Since the ecoff format was not easily
6943 extensible to handle new languages such as C++, this appeared to be a
6944 good way to put C++ debugging info into MIPS binaries. This option
6945 will be supported in the GNU C compiler, version 2, when it is
6948 * New features for SVR4
6950 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
6951 shared libraries. Debugging dynamically linked programs should present
6952 only minor differences from debugging statically linked programs.
6954 The `info proc' command will print out information about any process
6955 on an SVR4 system (including the one you are debugging). At the moment,
6956 it prints the address mappings of the process.
6958 If you bring up GDB on another SVR4 system, please send mail to
6959 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
6961 * Better dynamic linking support in SunOS
6963 Reading symbols from shared libraries which contain debugging symbols
6964 now works properly. However, there remain issues such as automatic
6965 skipping of `transfer vector' code during function calls, which
6966 make it harder to debug code in a shared library, than to debug the
6967 same code linked statically.
6971 GDB is now using the latest `getopt' routines from the FSF. This
6972 version accepts the -- prefix for options with long names. GDB will
6973 continue to accept the old forms (-option and +option) as well.
6974 Various single letter abbreviations for options have been explicity
6975 added to the option table so that they won't get overshadowed in the
6976 future by other options that begin with the same letter.
6980 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
6981 Many assorted bugs have been handled. Many more remain to be handled.
6982 See the various ChangeLog files (primarily in gdb and bfd) for details.
6985 *** Changes in GDB-4.3:
6987 * New machines supported (host and target)
6989 Amiga 3000 running Amix m68k-cbm-svr4 or amix
6990 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
6991 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
6993 * Almost SCO Unix support
6995 We had hoped to support:
6996 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
6997 (except for core file support), but we discovered very late in the release
6998 that it has problems with process groups that render gdb unusable. Sorry
6999 about that. I encourage people to fix it and post the fixes.
7001 * Preliminary ELF and DWARF support
7003 GDB can read ELF object files on System V Release 4, and can handle
7004 debugging records for C, in DWARF format, in ELF files. This support
7005 is preliminary. If you bring up GDB on another SVR4 system, please
7006 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
7011 GDB now uses the latest `readline' library. One user-visible change
7012 is that two tabs will list possible command completions, which previously
7013 required typing M-? (meta-question mark, or ESC ?).
7017 The `stepi' bug that many of you noticed has been squashed.
7018 Many bugs in C++ have been handled. Many more remain to be handled.
7019 See the various ChangeLog files (primarily in gdb and bfd) for details.
7021 * State of the MIPS world (in case you wondered):
7023 GDB can understand the symbol tables emitted by the compilers
7024 supplied by most vendors of MIPS-based machines, including DEC. These
7025 symbol tables are in a format that essentially nobody else uses.
7027 Some versions of gcc come with an assembler post-processor called
7028 mips-tfile. This program is required if you want to do source-level
7029 debugging of gcc-compiled programs. I believe FSF does not ship
7030 mips-tfile with gcc version 1, but it will eventually come with gcc
7033 Debugging of g++ output remains a problem. g++ version 1.xx does not
7034 really support it at all. (If you're lucky, you should be able to get
7035 line numbers and stack traces to work, but no parameters or local
7036 variables.) With some work it should be possible to improve the
7039 When gcc version 2 is released, you will have somewhat better luck.
7040 However, even then you will get confusing results for inheritance and
7043 We will eventually provide full debugging of g++ output on
7044 DECstations. This will probably involve some kind of stabs-in-ecoff
7045 encapulation, but the details have not been worked out yet.
7048 *** Changes in GDB-4.2:
7050 * Improved configuration
7052 Only one copy of `configure' exists now, and it is not self-modifying.
7053 Porting BFD is simpler.
7057 The `step' and `next' commands now only stop at the first instruction
7058 of a source line. This prevents the multiple stops that used to occur
7059 in switch statements, for-loops, etc. `Step' continues to stop if a
7060 function that has debugging information is called within the line.
7064 Lots of small bugs fixed. More remain.
7066 * New host supported (not target)
7068 Intel 386 PC clone running Mach i386-none-mach
7071 *** Changes in GDB-4.1:
7073 * Multiple source language support
7075 GDB now has internal scaffolding to handle several source languages.
7076 It determines the type of each source file from its filename extension,
7077 and will switch expression parsing and number formatting to match the
7078 language of the function in the currently selected stack frame.
7079 You can also specifically set the language to be used, with
7080 `set language c' or `set language modula-2'.
7084 GDB now has preliminary support for the GNU Modula-2 compiler,
7085 currently under development at the State University of New York at
7086 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
7087 continue through the fall of 1991 and into 1992.
7089 Other Modula-2 compilers are currently not supported, and attempting to
7090 debug programs compiled with them will likely result in an error as the
7091 symbol table is read. Feel free to work on it, though!
7093 There are hooks in GDB for strict type checking and range checking,
7094 in the `Modula-2 philosophy', but they do not currently work.
7098 GDB can now write to executable and core files (e.g. patch
7099 a variable's value). You must turn this switch on, specify
7100 the file ("exec foo" or "core foo"), *then* modify it, e.g.
7101 by assigning a new value to a variable. Modifications take
7104 * Automatic SunOS shared library reading
7106 When you run your program, GDB automatically determines where its
7107 shared libraries (if any) have been loaded, and reads their symbols.
7108 The `share' command is no longer needed. This also works when
7109 examining core files.
7113 You can specify the number of lines that the `list' command shows.
7116 * New machines supported (host and target)
7118 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
7119 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
7120 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
7122 * New hosts supported (not targets)
7124 IBM RT/PC: romp-ibm-aix or rtpc
7126 * New targets supported (not hosts)
7128 AMD 29000 embedded with COFF a29k-none-coff
7129 AMD 29000 embedded with a.out a29k-none-aout
7130 Ultracomputer remote kernel debug a29k-nyu-kern
7132 * New remote interfaces
7138 *** Changes in GDB-4.0:
7142 Wide output is wrapped at good places to make the output more readable.
7144 Gdb now supports cross-debugging from a host machine of one type to a
7145 target machine of another type. Communication with the target system
7146 is over serial lines. The ``target'' command handles connecting to the
7147 remote system; the ``load'' command will download a program into the
7148 remote system. Serial stubs for the m68k and i386 are provided. Gdb
7149 also supports debugging of realtime processes running under VxWorks,
7150 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
7151 stub on the target system.
7153 New CPUs supported include the AMD 29000 and Intel 960.
7155 GDB now reads object files and symbol tables via a ``binary file''
7156 library, which allows a single copy of GDB to debug programs of multiple
7157 object file types such as a.out and coff.
7159 There is now a GDB reference card in "doc/refcard.tex". (Make targets
7160 refcard.dvi and refcard.ps are available to format it).
7163 * Control-Variable user interface simplified
7165 All variables that control the operation of the debugger can be set
7166 by the ``set'' command, and displayed by the ``show'' command.
7168 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
7169 ``Show prompt'' produces the response:
7170 Gdb's prompt is new-gdb=>.
7172 What follows are the NEW set commands. The command ``help set'' will
7173 print a complete list of old and new set commands. ``help set FOO''
7174 will give a longer description of the variable FOO. ``show'' will show
7175 all of the variable descriptions and their current settings.
7177 confirm on/off: Enables warning questions for operations that are
7178 hard to recover from, e.g. rerunning the program while
7179 it is already running. Default is ON.
7181 editing on/off: Enables EMACS style command line editing
7182 of input. Previous lines can be recalled with
7183 control-P, the current line can be edited with control-B,
7184 you can search for commands with control-R, etc.
7187 history filename NAME: NAME is where the gdb command history
7188 will be stored. The default is .gdb_history,
7189 or the value of the environment variable
7192 history size N: The size, in commands, of the command history. The
7193 default is 256, or the value of the environment variable
7196 history save on/off: If this value is set to ON, the history file will
7197 be saved after exiting gdb. If set to OFF, the
7198 file will not be saved. The default is OFF.
7200 history expansion on/off: If this value is set to ON, then csh-like
7201 history expansion will be performed on
7202 command line input. The default is OFF.
7204 radix N: Sets the default radix for input and output. It can be set
7205 to 8, 10, or 16. Note that the argument to "radix" is interpreted
7206 in the current radix, so "set radix 10" is always a no-op.
7208 height N: This integer value is the number of lines on a page. Default
7209 is 24, the current `stty rows'' setting, or the ``li#''
7210 setting from the termcap entry matching the environment
7213 width N: This integer value is the number of characters on a line.
7214 Default is 80, the current `stty cols'' setting, or the ``co#''
7215 setting from the termcap entry matching the environment
7218 Note: ``set screensize'' is obsolete. Use ``set height'' and
7219 ``set width'' instead.
7221 print address on/off: Print memory addresses in various command displays,
7222 such as stack traces and structure values. Gdb looks
7223 more ``symbolic'' if you turn this off; it looks more
7224 ``machine level'' with it on. Default is ON.
7226 print array on/off: Prettyprint arrays. New convenient format! Default
7229 print demangle on/off: Print C++ symbols in "source" form if on,
7232 print asm-demangle on/off: Same, for assembler level printouts
7235 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
7238 * Support for Epoch Environment.
7240 The epoch environment is a version of Emacs v18 with windowing. One
7241 new command, ``inspect'', is identical to ``print'', except that if you
7242 are running in the epoch environment, the value is printed in its own
7246 * Support for Shared Libraries
7248 GDB can now debug programs and core files that use SunOS shared libraries.
7249 Symbols from a shared library cannot be referenced
7250 before the shared library has been linked with the program (this
7251 happens after you type ``run'' and before the function main() is entered).
7252 At any time after this linking (including when examining core files
7253 from dynamically linked programs), gdb reads the symbols from each
7254 shared library when you type the ``sharedlibrary'' command.
7255 It can be abbreviated ``share''.
7257 sharedlibrary REGEXP: Load shared object library symbols for files
7258 matching a unix regular expression. No argument
7259 indicates to load symbols for all shared libraries.
7261 info sharedlibrary: Status of loaded shared libraries.
7266 A watchpoint stops execution of a program whenever the value of an
7267 expression changes. Checking for this slows down execution
7268 tremendously whenever you are in the scope of the expression, but is
7269 quite useful for catching tough ``bit-spreader'' or pointer misuse
7270 problems. Some machines such as the 386 have hardware for doing this
7271 more quickly, and future versions of gdb will use this hardware.
7273 watch EXP: Set a watchpoint (breakpoint) for an expression.
7275 info watchpoints: Information about your watchpoints.
7277 delete N: Deletes watchpoint number N (same as breakpoints).
7278 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
7279 enable N: Re-enables watchpoint number N (same as breakpoints).
7282 * C++ multiple inheritance
7284 When used with a GCC version 2 compiler, GDB supports multiple inheritance
7287 * C++ exception handling
7289 Gdb now supports limited C++ exception handling. Besides the existing
7290 ability to breakpoint on an exception handler, gdb can breakpoint on
7291 the raising of an exception (before the stack is peeled back to the
7294 catch FOO: If there is a FOO exception handler in the dynamic scope,
7295 set a breakpoint to catch exceptions which may be raised there.
7296 Multiple exceptions (``catch foo bar baz'') may be caught.
7298 info catch: Lists all exceptions which may be caught in the
7299 current stack frame.
7302 * Minor command changes
7304 The command ``call func (arg, arg, ...)'' now acts like the print
7305 command, except it does not print or save a value if the function's result
7306 is void. This is similar to dbx usage.
7308 The ``up'' and ``down'' commands now always print the frame they end up
7309 at; ``up-silently'' and `down-silently'' can be used in scripts to change
7310 frames without printing.
7312 * New directory command
7314 'dir' now adds directories to the FRONT of the source search path.
7315 The path starts off empty. Source files that contain debug information
7316 about the directory in which they were compiled can be found even
7317 with an empty path; Sun CC and GCC include this information. If GDB can't
7318 find your source file in the current directory, type "dir .".
7320 * Configuring GDB for compilation
7322 For normal use, type ``./configure host''. See README or gdb.texinfo
7325 GDB now handles cross debugging. If you are remotely debugging between
7326 two different machines, type ``./configure host -target=targ''.
7327 Host is the machine where GDB will run; targ is the machine
7328 where the program that you are debugging will run.