1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * GDB now has an interface for JIT compilation. Applications that
7 dynamically generate code can create symbol files in memory and register
8 them with GDB. For users, the feature should work transparently, and
9 for JIT developers, the interface is documented in the GDB manual in the
10 "JIT Compilation Interface" chapter.
12 * Tracepoints may now be conditional. The syntax is as for
13 breakpoints; either an "if" clause appended to the "trace" command,
14 or the "condition" command is available. GDB sends the condition to
15 the target for evaluation using the same bytecode format as is used
16 for tracepoint actions.
18 * "disassemble" command with a /r modifier, print the raw instructions
19 in hex as well as in symbolic form."
21 * Process record and replay
23 In a architecture environment that supports ``process record and
24 replay'', ``process record and replay'' target can record a log of
25 the process execution, and replay it with both forward and reverse
28 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
29 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
30 set execution-direction {forward|reverse}, for targets that support
33 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
34 feature is available with a native GDB running on kernel version
37 * GDB now has support for multi-byte and wide character sets on the
38 target. Strings whose character type is wchar_t, char16_t, or
39 char32_t are now correctly printed. GDB supports wide- and unicode-
40 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
41 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
42 `printf'. This feature requires iconv to work properly; if your
43 system does not have a working iconv, GDB can use GNU libiconv. See
44 the installation instructions for more information.
46 * GDB now supports automatic retrieval of shared library files from
47 remote targets. To use this feature, specify a system root that begins
48 with the `remote:' prefix, either via the `set sysroot' command or via
49 the `--with-sysroot' configure-time option.
51 * "info sharedlibrary" now takes an optional regex of libraries to show,
52 and it now reports if a shared library has no debugging information.
54 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
55 now complete on file names.
57 * When completing in expressions, gdb will attempt to limit
58 completions to allowable structure or union fields, where appropriate.
59 For instance, consider:
61 # struct example { int f1; double f2; };
62 # struct example variable;
65 If the user types TAB at the end of this command line, the available
66 completions will be "f1" and "f2".
68 * Inlined functions are now supported. They show up in backtraces, and
69 the "step", "next", and "finish" commands handle them automatically.
71 * GDB now supports the token-splicing (##) and stringification (#)
72 operators when expanding macros. It also supports variable-arity
75 * GDB now supports inspecting extra signal information, exported by
76 the new $_siginfo convenience variable. The feature is currently
77 implemented on linux ARM, i386 and amd64.
79 * GDB can now display the VFP floating point registers and NEON vector
80 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
81 can provide these registers (requires Linux 2.6.30 or later). Remote
82 and simulator targets may also provide them.
87 Search memory for a sequence of bytes.
90 Turn off `+'/`-' protocol acknowledgments to permit more efficient
91 operation over reliable transport links. Use of this packet is
92 controlled by the `set remote noack-packet' command.
95 Kill the process with the specified process ID. Use this in preference
96 to `k' when multiprocess protocol extensions are supported.
99 Obtains additional operating system information
103 Read or write additional signal information.
105 * Removed remote protocol undocumented extension
107 An undocumented extension to the remote protocol's `S' stop reply
108 packet that permited the stub to pass a process id was removed.
109 Remote servers should use the `T' stop reply packet instead.
111 * The "disassemble" command now supports an optional /m modifier to print mixed
114 * GDB now supports multiple function calling conventions according to the
115 DWARF-2 DW_AT_calling_convention function attribute.
117 * The SH target utilizes the aforementioned change to distinguish between gcc
118 and Renesas calling convention. It also adds the new CLI commands
119 `set/show sh calling-convention'.
121 * GDB can now read compressed debug sections, as produced by GNU gold
122 with the --compress-debug-sections=zlib flag.
124 * 64-bit core files are now supported on AIX.
126 * Thread switching is now supported on Tru64.
128 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
129 which will be allocated using malloc later in program execution.
131 * The qXfer:libraries:read remote procotol packet now allows passing a
132 list of section offsets.
134 * On GNU/Linux, GDB can now attach to stopped processes. Several race
135 conditions handling signals delivered during attach or thread creation
136 have also been fixed.
138 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
139 From the user's standpoint, all unqualified instances of True and False
140 are treated as the standard definitions, regardless of context.
142 * GDB now parses C++ symbol and type names more flexibly. For
145 template<typename T> class C { };
148 GDB will now correctly handle all of:
150 ptype C<char const *>
152 ptype C<const char *>
155 * New features in the GDB remote stub, gdbserver
157 - The "--wrapper" command-line argument tells gdbserver to use a
158 wrapper program to launch programs for debugging.
160 - On PowerPC and S/390 targets, it is now possible to use a single
161 gdbserver executable to debug both 32-bit and 64-bit programs.
162 (This requires gdbserver itself to be built as a 64-bit executable.)
164 - gdbserver uses the new noack protocol mode for TCP connections to
165 reduce communications latency, if also supported and enabled in GDB.
167 - Support for the sparc64-linux-gnu target is now included in
170 - The amd64-linux build of gdbserver now supports debugging both
171 32-bit and 64-bit programs.
173 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
174 now support hardware watchpoints, and will use them automatically
179 GDB now has support for scripting using Python. Whether this is
180 available is determined at configure time.
182 New GDB commands can now be written in Python.
184 * Ada tasking support
186 Ada tasks can now be inspected in GDB. The following commands have
190 Print the list of Ada tasks.
192 Print detailed information about task number N.
194 Print the task number of the current task.
196 Switch the context of debugging to task number N.
198 * Support for user-defined prefixed commands. The "define" command can
199 add new commands to existing prefixes, e.g. "target".
201 * Multi-inferior, multi-process debugging.
203 GDB now has generalized support for multi-inferior debugging. See
204 "Debugging Multiple Inferiors" in the manual for more information.
205 Although availability still depends on target support, the command
206 set is more uniform now. The GNU/Linux specific multi-forks support
207 has been migrated to this new framework. This implied some user
208 visible changes; see "New commands" and also "Removed commands"
211 * Target descriptions can now describe the target OS ABI. See the
212 "Target Description Format" section in the user manual for more
215 * Target descriptions can now describe "compatible" architectures
216 to indicate that the target can execute applications for a different
217 architecture in addition to those for the main target architecture.
218 See the "Target Description Format" section in the user manual for
221 * Multi-architecture debugging.
223 GDB now includes general supports for debugging applications on
224 hybrid systems that use more than one single processor architecture
225 at the same time. Each such hybrid architecture still requires
226 specific support to be added. The only hybrid architecture supported
227 in this version of GDB is the Cell Broadband Engine.
229 * GDB now supports integrated debugging of Cell/B.E. applications that
230 use both the PPU and SPU architectures. To enable support for hybrid
231 Cell/B.E. debugging, you need to configure GDB to support both the
232 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
233 --enable-targets configure option.
235 * New commands (for set/show, see "New options" below)
237 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
239 Search memory for a sequence of bytes.
241 maint set python print-stack
242 maint show python print-stack
243 Show a stack trace when an error is encountered in a Python script.
246 Invoke CODE by passing it to the Python interpreter.
251 These allow macros to be defined, undefined, and listed
255 Show operating system information about processes.
258 List the inferiors currently under GDB's control.
261 Switch focus to inferior number NUM.
264 Detach from inferior number NUM.
267 Kill inferior number NUM.
272 show spu stop-on-load
273 Control whether to stop for new SPE threads during Cell/B.E. debugging.
275 set spu auto-flush-cache
276 show spu auto-flush-cache
277 Control whether to automatically flush the software-managed cache
278 during Cell/B.E. debugging.
280 set sh calling-convention
281 show sh calling-convention
282 Control the calling convention used when calling SH target functions.
286 Control display of timestamps with GDB debugging output.
288 set disassemble-next-line
289 show disassemble-next-line
290 Control display of disassembled source lines or instructions when
293 set remote noack-packet
294 show remote noack-packet
295 Set/show the use of remote protocol QStartNoAckMode packet. See above
296 under "New remote packets."
298 set remote query-attached-packet
299 show remote query-attached-packet
300 Control use of remote protocol `qAttached' (query-attached) packet.
302 set remote read-siginfo-object
303 show remote read-siginfo-object
304 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
307 set remote write-siginfo-object
308 show remote write-siginfo-object
309 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
312 set remote reverse-continue
313 show remote reverse-continue
314 Control use of remote protocol 'bc' (reverse-continue) packet.
316 set remote reverse-step
317 show remote reverse-step
318 Control use of remote protocol 'bs' (reverse-step) packet.
320 set displaced-stepping
321 show displaced-stepping
322 Control displaced stepping mode. Displaced stepping is a way to
323 single-step over breakpoints without removing them from the debuggee.
324 Also known as "out-of-line single-stepping".
328 Control display of debugging info for displaced stepping.
330 maint set internal-error
331 maint show internal-error
332 Control what GDB does when an internal error is detected.
334 maint set internal-warning
335 maint show internal-warning
336 Control what GDB does when an internal warning is detected.
341 Use a wrapper program to launch programs for debugging.
343 set multiple-symbols (all|ask|cancel)
344 show multiple-symbols
345 The value of this variable can be changed to adjust the debugger behavior
346 when an expression or a breakpoint location contains an ambiguous symbol
347 name (an overloaded function name, for instance).
349 set breakpoint always-inserted
350 show breakpoint always-inserted
351 Keep breakpoints always inserted in the target, as opposed to inserting
352 them when resuming the target, and removing them when the target stops.
353 This option can improve debugger performance on slow remote targets.
355 set arm fallback-mode (arm|thumb|auto)
356 show arm fallback-mode
357 set arm force-mode (arm|thumb|auto)
359 These commands control how ARM GDB determines whether instructions
360 are ARM or Thumb. The default for both settings is auto, which uses
361 the current CPSR value for instructions without symbols; previous
362 versions of GDB behaved as if "set arm fallback-mode arm".
364 set disable-randomization
365 show disable-randomization
366 Standalone programs run with the virtual address space randomization enabled
367 by default on some platforms. This option keeps the addresses stable across
368 multiple debugging sessions.
372 Control whether other threads are stopped or not when some thread hits
377 Requests that asynchronous execution is enabled in the target, if available.
378 In this case, it's possible to resume target in the background, and interact
379 with GDB while the target is running. "show target-async" displays the
380 current state of asynchronous execution of the target.
382 set target-wide-charset
383 show target-wide-charset
384 The target-wide-charset is the name of the character set that GDB
385 uses when printing characters whose type is wchar_t.
387 set tcp auto-retry (on|off)
389 set tcp connect-timeout
390 show tcp connect-timeout
391 These commands allow GDB to retry failed TCP connections to a remote stub
392 with a specified timeout period; this is useful if the stub is launched
393 in parallel with GDB but may not be ready to accept connections immediately.
395 set libthread-db-search-path
396 show libthread-db-search-path
397 Control list of directories which GDB will search for appropriate
400 set schedule-multiple (on|off)
401 show schedule-multiple
402 Allow GDB to resume all threads of all processes or only threads of
407 Use more aggressive caching for accesses to the stack. This improves
408 performance of remote debugging (particularly backtraces) without
409 affecting correctness.
411 set interactive-mode (on|off|auto)
412 show interactive-mode
413 Control whether GDB runs in interactive mode (on) or not (off).
414 When in interactive mode, GDB waits for the user to answer all
415 queries. Otherwise, GDB does not wait and assumes the default
416 answer. When set to auto (the default), GDB determines which
417 mode to use based on the stdin settings.
422 For program forks, this is replaced by the new more generic `info
423 inferiors' command. To list checkpoints, you can still use the
424 `info checkpoints' command, which was an alias for the `info forks'
428 Replaced by the new `inferior' command. To switch between
429 checkpoints, you can still use the `restart' command, which was an
430 alias for the `fork' command.
433 This is removed, since some targets don't have a notion of
434 processes. To switch between processes, you can still use the
435 `inferior' command using GDB's own inferior number.
438 For program forks, this is replaced by the new more generic `kill
439 inferior' command. To delete a checkpoint, you can still use the
440 `delete checkpoint' command, which was an alias for the `delete
444 For program forks, this is replaced by the new more generic `detach
445 inferior' command. To detach a checkpoint, you can still use the
446 `detach checkpoint' command, which was an alias for the `detach
449 * New native configurations
451 x86/x86_64 Darwin i[34567]86-*-darwin*
453 x86_64 MinGW x86_64-*-mingw*
457 Lattice Mico32 lm32-*
458 x86 DICOS i[34567]86-*-dicos*
459 x86_64 DICOS x86_64-*-dicos*
462 * The GDB remote stub, gdbserver, now supports x86 Windows CE
463 (mingw32ce) debugging.
469 These commands were actually not implemented on any target.
471 *** Changes in GDB 6.8
473 * New native configurations
475 NetBSD/hppa hppa*-*netbsd*
476 Xtensa GNU/Linux xtensa*-*-linux*
480 NetBSD/hppa hppa*-*-netbsd*
481 Xtensa GNU/Lunux xtensa*-*-linux*
483 * Change in command line behavior -- corefiles vs. process ids.
485 When the '-p NUMBER' or '--pid NUMBER' options are used, and
486 attaching to process NUMBER fails, GDB no longer attempts to open a
487 core file named NUMBER. Attaching to a program using the -c option
488 is no longer supported. Instead, use the '-p' or '--pid' options.
490 * GDB can now be built as a native debugger for debugging Windows x86
491 (mingw32) Portable Executable (PE) programs.
493 * Pending breakpoints no longer change their number when their address
496 * GDB now supports breakpoints with multiple locations,
497 including breakpoints on C++ constructors, inside C++ templates,
498 and in inlined functions.
500 * GDB's ability to debug optimized code has been improved. GDB more
501 accurately identifies function bodies and lexical blocks that occupy
502 more than one contiguous range of addresses.
504 * Target descriptions can now describe registers for PowerPC.
506 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
507 registers on PowerPC targets.
509 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
510 targets even when the libthread_db library is not available.
512 * The GDB remote stub, gdbserver, now supports the new file transfer
513 commands (remote put, remote get, and remote delete).
515 * The GDB remote stub, gdbserver, now supports run and attach in
516 extended-remote mode.
518 * hppa*64*-*-hpux11* target broken
519 The debugger is unable to start a program and fails with the following
520 error: "Error trying to get information about dynamic linker".
521 The gdb-6.7 release is also affected.
523 * GDB now supports the --enable-targets= configure option to allow
524 building a single GDB executable that supports multiple remote
525 target architectures.
527 * GDB now supports debugging C and C++ programs which use the
528 Decimal Floating Point extension. In addition, the PowerPC target
529 now has a set of pseudo-registers to inspect decimal float values
530 stored in two consecutive float registers.
532 * The -break-insert MI command can optionally create pending
535 * Improved support for debugging Ada
536 Many improvements to the Ada language support have been made. These
538 - Better support for Ada2005 interface types
539 - Improved handling of arrays and slices in general
540 - Better support for Taft-amendment types
541 - The '{type} ADDRESS' expression is now allowed on the left hand-side
543 - Improved command completion in Ada
546 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
551 set print frame-arguments (all|scalars|none)
552 show print frame-arguments
553 The value of this variable can be changed to control which argument
554 values should be printed by the debugger when displaying a frame.
559 Transfer files to and from a remote target, and delete remote files.
566 Transfer files to and from a remote target, and delete remote files.
575 Open, close, read, write, and delete files on the remote system.
578 Attach to an existing process on the remote system, in extended-remote
582 Run a new process on the remote system, in extended-remote mode.
584 *** Changes in GDB 6.7
586 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
587 bfd, libiberty and opcodes, as revealed by static analysis donated by
588 Coverity, Inc. (http://scan.coverity.com).
590 * When looking up multiply-defined global symbols, GDB will now prefer the
591 symbol definition in the current shared library if it was built using the
592 -Bsymbolic linker option.
594 * When the Text User Interface (TUI) is not configured, GDB will now
595 recognize the -tui command-line option and print a message that the TUI
598 * The GDB remote stub, gdbserver, now has lower overhead for high
599 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
601 * GDB for MIPS targets now autodetects whether a remote target provides
602 32-bit or 64-bit register values.
604 * Support for C++ member pointers has been improved.
606 * GDB now understands XML target descriptions, which specify the
607 target's overall architecture. GDB can read a description from
608 a local file or over the remote serial protocol.
610 * Vectors of single-byte data use a new integer type which is not
611 automatically displayed as character or string data.
613 * The /s format now works with the print command. It displays
614 arrays of single-byte integers and pointers to single-byte integers
617 * Target descriptions can now describe target-specific registers,
618 for architectures which have implemented the support (currently
619 only ARM, M68K, and MIPS).
621 * GDB and the GDB remote stub, gdbserver, now support the XScale
624 * The GDB remote stub, gdbserver, has been updated to support
625 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
626 has been rewritten to use the standard GDB remote protocol.
628 * GDB can now step into C++ functions which are called through thunks.
630 * GDB for the Cell/B.E. SPU now supports overlay debugging.
632 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
633 layout. It also supports a TextSeg= and DataSeg= response when only
634 segment base addresses (rather than offsets) are available.
636 * The /i format now outputs any trailing branch delay slot instructions
637 immediately following the last instruction within the count specified.
639 * The GDB remote protocol "T" stop reply packet now supports a
640 "library" response. Combined with the new "qXfer:libraries:read"
641 packet, this response allows GDB to debug shared libraries on targets
642 where the operating system manages the list of loaded libraries (e.g.
643 Windows and SymbianOS).
645 * The GDB remote stub, gdbserver, now supports dynamic link libraries
646 (DLLs) on Windows and Windows CE targets.
648 * GDB now supports a faster verification that a .debug file matches its binary
649 according to its build-id signature, if the signature is present.
655 Enable or disable hardware flow control (RTS/CTS) on the serial port
656 when debugging using remote targets.
658 set mem inaccessible-by-default
659 show mem inaccessible-by-default
660 If the target supplies a memory map, for instance via the remote
661 protocol's "qXfer:memory-map:read" packet, setting this variable
662 prevents GDB from accessing memory outside the memory map. This
663 is useful for targets with memory mapped registers or which react
664 badly to accesses of unmapped address space.
666 set breakpoint auto-hw
667 show breakpoint auto-hw
668 If the target supplies a memory map, for instance via the remote
669 protocol's "qXfer:memory-map:read" packet, setting this variable
670 lets GDB use hardware breakpoints automatically for memory regions
671 where it can not use software breakpoints. This covers both the
672 "break" command and internal breakpoints used for other commands
673 including "next" and "finish".
676 catch exception unhandled
677 Stop the program execution when Ada exceptions are raised.
680 Stop the program execution when an Ada assertion failed.
684 Set an alternate system root for target files. This is a more
685 general version of "set solib-absolute-prefix", which is now
686 an alias to "set sysroot".
689 Provide extended SPU facility status information. This set of
690 commands is available only when debugging the Cell/B.E. SPU
693 * New native configurations
695 OpenBSD/sh sh*-*openbsd*
700 Use the specified local file as an XML target description, and do
701 not query the target for its built-in description.
705 OpenBSD/sh sh*-*-openbsd*
706 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
707 Toshiba Media Processor mep-elf
712 Ignore the specified signals; pass them directly to the debugged program
713 without stopping other threads or reporting them to GDB.
716 Read an XML target description from the target, which describes its
721 Read or write contents of an spufs file on the target system. These
722 packets are available only on the Cell/B.E. SPU architecture.
724 qXfer:libraries:read:
725 Report the loaded shared libraries. Combined with new "T" packet
726 response, this packet allows GDB to debug shared libraries on
727 targets where the operating system manages the list of loaded
728 libraries (e.g. Windows and SymbianOS).
732 Support for these obsolete configurations has been removed.
741 i[34567]86-*-netware*
742 i[34567]86-*-sco3.2v5*
743 i[34567]86-*-sco3.2v4*
745 i[34567]86-*-sysv4.2*
748 i[34567]86-*-unixware2*
749 i[34567]86-*-unixware*
758 * Other removed features
765 Various m68k-only ROM monitors.
772 Various Renesas ROM monitors and debugging interfaces for SH and
777 Support for a Macraigor serial interface to on-chip debugging.
778 GDB does not directly support the newer parallel or USB
783 A debug information format. The predecessor to DWARF 2 and
784 DWARF 3, which are still supported.
786 Support for the HP aCC compiler on HP-UX/PA-RISC
788 SOM-encapsulated symbolic debugging information, automatic
789 invocation of pxdb, and the aCC custom C++ ABI. This does not
790 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
791 with aCC can still be debugged on an assembly level.
795 A MIPS-specific format used to describe stack frame layout
796 in debugging information.
800 GDB could work with an older version of Guile to debug
801 the interpreter and Scheme programs running in it.
803 set mips stack-arg-size
804 set mips saved-gpreg-size
806 Use "set mips abi" to control parameter passing for MIPS.
808 *** Changes in GDB 6.6
813 Cell Broadband Engine SPU spu-elf
815 * GDB can now be configured as a cross-debugger targeting native Windows
816 (mingw32) or Cygwin. It can communicate with a remote debugging stub
817 running on a Windows system over TCP/IP to debug Windows programs.
819 * The GDB remote stub, gdbserver, has been updated to support Windows and
820 Cygwin debugging. Both single-threaded and multi-threaded programs are
823 * The "set trust-readonly-sections" command works again. This command was
824 broken in GDB 6.3, 6.4, and 6.5.
826 * The "load" command now supports writing to flash memory, if the remote
827 stub provides the required support.
829 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
830 longer requires symbolic debug information (e.g. DWARF-2).
835 unset substitute-path
837 Manage a list of substitution rules that GDB uses to rewrite the name
838 of the directories where the sources are located. This can be useful
839 for instance when the sources were moved to a different location
840 between compilation and debugging.
844 Print each CLI command as it is executed. Each command is prefixed with
845 a number of `+' symbols representing the nesting depth.
846 The source command now has a `-v' option to enable the same feature.
850 The ARM Demon monitor support (RDP protocol, "target rdp").
852 Kernel Object Display, an embedded debugging feature which only worked with
853 an obsolete version of Cisco IOS.
855 The 'set download-write-size' and 'show download-write-size' commands.
860 Tell a stub about GDB client features, and request remote target features.
861 The first feature implemented is PacketSize, which allows the target to
862 specify the size of packets it can handle - to minimize the number of
863 packets required and improve performance when connected to a remote
867 Fetch an OS auxilliary vector from the remote stub. This packet is a
868 more efficient replacement for qPart:auxv:read.
870 qXfer:memory-map:read:
871 Fetch a memory map from the remote stub, including information about
872 RAM, ROM, and flash memory devices.
877 Erase and program a flash memory device.
879 * Removed remote packets
882 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
883 used it, and only gdbserver implemented it.
885 *** Changes in GDB 6.5
889 Renesas M32C/M16C m32c-elf
891 Morpho Technologies ms1 ms1-elf
895 init-if-undefined Initialize a convenience variable, but
896 only if it doesn't already have a value.
898 The following commands are presently only implemented for native GNU/Linux:
900 checkpoint Save a snapshot of the program state.
902 restart <n> Return the program state to a
903 previously saved state.
905 info checkpoints List currently saved checkpoints.
907 delete-checkpoint <n> Delete a previously saved checkpoint.
909 set|show detach-on-fork Tell gdb whether to detach from a newly
910 forked process, or to keep debugging it.
912 info forks List forks of the user program that
913 are available to be debugged.
915 fork <n> Switch to debugging one of several
916 forks of the user program that are
917 available to be debugged.
919 delete-fork <n> Delete a fork from the list of forks
920 that are available to be debugged (and
921 kill the forked process).
923 detach-fork <n> Delete a fork from the list of forks
924 that are available to be debugged (and
925 allow the process to continue).
929 Morpho Technologies ms2 ms1-elf
931 * Improved Windows host support
933 GDB now builds as a cross debugger hosted on i686-mingw32, including
934 native console support, and remote communications using either
935 network sockets or serial ports.
937 * Improved Modula-2 language support
939 GDB can now print most types in the Modula-2 syntax. This includes:
940 basic types, set types, record types, enumerated types, range types,
941 pointer types and ARRAY types. Procedure var parameters are correctly
942 printed and hexadecimal addresses and character constants are also
943 written in the Modula-2 syntax. Best results can be obtained by using
944 GNU Modula-2 together with the -gdwarf-2 command line option.
948 The ARM rdi-share module.
950 The Netware NLM debug server.
952 *** Changes in GDB 6.4
954 * New native configurations
956 OpenBSD/arm arm*-*-openbsd*
957 OpenBSD/mips64 mips64-*-openbsd*
961 Morpho Technologies ms1 ms1-elf
963 * New command line options
965 --batch-silent As for --batch, but totally silent.
966 --return-child-result The debugger will exist with the same value
967 the child (debugged) program exited with.
968 --eval-command COMMAND, -ex COMMAND
969 Execute a single GDB CLI command. This may be
970 specified multiple times and in conjunction
971 with the --command (-x) option.
973 * Deprecated commands removed
975 The following commands, that were deprecated in 2000, have been
979 set|show arm disassembly-flavor set|show arm disassembler
980 othernames set arm disassembler
981 set|show remotedebug set|show debug remote
982 set|show archdebug set|show debug arch
983 set|show eventdebug set|show debug event
986 * New BSD user-level threads support
988 It is now possible to debug programs using the user-level threads
989 library on OpenBSD and FreeBSD. Currently supported (target)
992 FreeBSD/amd64 x86_64-*-freebsd*
993 FreeBSD/i386 i386-*-freebsd*
994 OpenBSD/i386 i386-*-openbsd*
996 Note that the new kernel threads libraries introduced in FreeBSD 5.x
997 are not yet supported.
999 * New support for Matsushita MN10300 w/sim added
1000 (Work in progress). mn10300-elf.
1002 * REMOVED configurations and files
1004 VxWorks and the XDR protocol *-*-vxworks
1005 Motorola MCORE mcore-*-*
1006 National Semiconductor NS32000 ns32k-*-*
1008 * New "set print array-indexes" command
1010 After turning this setting "on", GDB prints the index of each element
1011 when displaying arrays. The default is "off" to preserve the previous
1014 * VAX floating point support
1016 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1018 * User-defined command support
1020 In addition to using $arg0..$arg9 for argument passing, it is now possible
1021 to use $argc to determine now many arguments have been passed. See the
1022 section on user-defined commands in the user manual for more information.
1024 *** Changes in GDB 6.3:
1026 * New command line option
1028 GDB now accepts -l followed by a number to set the timeout for remote
1031 * GDB works with GCC -feliminate-dwarf2-dups
1033 GDB now supports a more compact representation of DWARF-2 debug
1034 information using DW_FORM_ref_addr references. These are produced
1035 by GCC with the option -feliminate-dwarf2-dups and also by some
1036 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1037 to use -feliminate-dwarf2-dups.
1039 * Internationalization
1041 When supported by the host system, GDB will be built with
1042 internationalization (libintl). The task of marking up the sources is
1043 continued, we're looking forward to our first translation.
1047 Initial support for debugging programs compiled with the GNAT
1048 implementation of the Ada programming language has been integrated
1049 into GDB. In this release, support is limited to expression evaluation.
1051 * New native configurations
1053 GNU/Linux/m32r m32r-*-linux-gnu
1057 GDB's remote protocol now includes support for the 'p' packet. This
1058 packet is used to fetch individual registers from a remote inferior.
1060 * END-OF-LIFE registers[] compatibility module
1062 GDB's internal register infrastructure has been completely rewritten.
1063 The new infrastructure making possible the implementation of key new
1064 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1067 GDB 6.3 will be the last release to include the the registers[]
1068 compatibility module that allowed out-of-date configurations to
1069 continue to work. This change directly impacts the following
1079 powerpc bdm protocol
1081 Unless there is activity to revive these configurations, they will be
1082 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1084 * OBSOLETE configurations and files
1086 Configurations that have been declared obsolete in this release have
1087 been commented out. Unless there is activity to revive these
1088 configurations, the next release of GDB will have their sources
1089 permanently REMOVED.
1098 *** Changes in GDB 6.2.1:
1100 * MIPS `break main; run' gave an heuristic-fence-post warning
1102 When attempting to run even a simple program, a warning about
1103 heuristic-fence-post being hit would be reported. This problem has
1106 * MIPS IRIX 'long double' crashed GDB
1108 When examining a long double variable, GDB would get a segmentation
1109 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1110 IRIX long double values).
1114 A bug in the VAX stack code was causing problems with the "next"
1115 command. This problem has been fixed.
1117 *** Changes in GDB 6.2:
1119 * Fix for ``many threads''
1121 On GNU/Linux systems that use the NPTL threads library, a program
1122 rapidly creating and deleting threads would confuse GDB leading to the
1125 ptrace: No such process.
1126 thread_db_get_info: cannot get thread info: generic error
1128 This problem has been fixed.
1130 * "-async" and "-noasync" options removed.
1132 Support for the broken "-noasync" option has been removed (it caused
1135 * New ``start'' command.
1137 This command runs the program until the begining of the main procedure.
1139 * New BSD Kernel Data Access Library (libkvm) interface
1141 Using ``target kvm'' it is now possible to debug kernel core dumps and
1142 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1143 platforms. Currently supported (native-only) configurations are:
1145 FreeBSD/amd64 x86_64-*-freebsd*
1146 FreeBSD/i386 i?86-*-freebsd*
1147 NetBSD/i386 i?86-*-netbsd*
1148 NetBSD/m68k m68*-*-netbsd*
1149 NetBSD/sparc sparc-*-netbsd*
1150 OpenBSD/amd64 x86_64-*-openbsd*
1151 OpenBSD/i386 i?86-*-openbsd*
1152 OpenBSD/m68k m68*-openbsd*
1153 OpenBSD/sparc sparc-*-openbsd*
1155 * Signal trampoline code overhauled
1157 Many generic problems with GDB's signal handling code have been fixed.
1158 These include: backtraces through non-contiguous stacks; recognition
1159 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1160 call; backtrace through a signal trampoline; step into and out of
1161 signal handlers; and single-stepping in the signal trampoline.
1163 Please note that kernel bugs are a limiting factor here. These
1164 features have been shown to work on an s390 GNU/Linux system that
1165 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1167 * Cygwin support for DWARF 2 added.
1169 * New native configurations
1171 GNU/Linux/hppa hppa*-*-linux*
1172 OpenBSD/hppa hppa*-*-openbsd*
1173 OpenBSD/m68k m68*-*-openbsd*
1174 OpenBSD/m88k m88*-*-openbsd*
1175 OpenBSD/powerpc powerpc-*-openbsd*
1176 NetBSD/vax vax-*-netbsd*
1177 OpenBSD/vax vax-*-openbsd*
1179 * END-OF-LIFE frame compatibility module
1181 GDB's internal frame infrastructure has been completely rewritten.
1182 The new infrastructure making it possible to support key new features
1183 including DWARF 2 Call Frame Information. To aid in the task of
1184 migrating old configurations to this new infrastructure, a
1185 compatibility module, that allowed old configurations to continue to
1186 work, was also included.
1188 GDB 6.2 will be the last release to include this frame compatibility
1189 module. This change directly impacts the following configurations:
1199 Unless there is activity to revive these configurations, they will be
1200 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1202 * REMOVED configurations and files
1204 Sun 3, running SunOS 3 m68*-*-sunos3*
1205 Sun 3, running SunOS 4 m68*-*-sunos4*
1206 Sun 2, running SunOS 3 m68000-*-sunos3*
1207 Sun 2, running SunOS 4 m68000-*-sunos4*
1208 Motorola 680x0 running LynxOS m68*-*-lynxos*
1209 AT&T 3b1/Unix pc m68*-att-*
1210 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1211 decstation mips-dec-* mips-little-*
1212 riscos mips-*-riscos* mips-*-sysv*
1213 sonymips mips-sony-*
1214 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1216 *** Changes in GDB 6.1.1:
1218 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1220 The TUI (Text-mode User Interface) is now built as part of a default
1221 GDB configuration. It is enabled by either selecting the TUI with the
1222 command line option "-i=tui" or by running the separate "gdbtui"
1223 program. For more information on the TUI, see the manual "Debugging
1226 * Pending breakpoint support (also included in GDB 6.1)
1228 Support has been added to allow you to specify breakpoints in shared
1229 libraries that have not yet been loaded. If a breakpoint location
1230 cannot be found, and the "breakpoint pending" option is set to auto,
1231 GDB queries you if you wish to make the breakpoint pending on a future
1232 shared-library load. If and when GDB resolves the breakpoint symbol,
1233 the pending breakpoint is removed as one or more regular breakpoints
1236 Pending breakpoints are very useful for GCJ Java debugging.
1238 * Fixed ISO-C build problems
1240 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1241 non ISO-C code that stopped them being built using a more strict ISO-C
1242 compiler (e.g., IBM's C compiler).
1244 * Fixed build problem on IRIX 5
1246 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1247 wasn't able to compile compile on an IRIX 5 system.
1249 * Added execute permission to gdb/gdbserver/configure
1251 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1252 permission. This bug would cause configure to fail on a number of
1253 systems (Solaris, IRIX). Ref: server/519.
1255 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1257 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1258 has been updated to use constant array sizes.
1260 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1262 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1263 its generated DWARF Call Frame Info. This encoding was causing GDB to
1264 panic, that panic has been fixed. Ref: gdb/1628.
1266 * Fixed a problem when examining parameters in shared library code.
1268 When examining parameters in optimized shared library code generated
1269 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1270 not available''. GDB now correctly displays the variable's value.
1272 *** Changes in GDB 6.1:
1274 * Removed --with-mmalloc
1276 Support for the mmalloc memory manager has been removed, as it
1277 conflicted with the internal gdb byte cache.
1279 * Changes in AMD64 configurations
1281 The AMD64 target now includes the %cs and %ss registers. As a result
1282 the AMD64 remote protocol has changed; this affects the floating-point
1283 and SSE registers. If you rely on those registers for your debugging,
1284 you should upgrade gdbserver on the remote side.
1286 * Revised SPARC target
1288 The SPARC target has been completely revised, incorporating the
1289 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1290 support for LynxOS and SunOS 4 has been dropped. Calling functions
1291 from within GDB on operating systems with a non-executable stack
1292 (Solaris, OpenBSD) now works.
1296 GDB has a new C++ demangler which does a better job on the mangled
1297 names generated by current versions of g++. It also runs faster, so
1298 with this and other changes gdb should now start faster on large C++
1301 * DWARF 2 Location Expressions
1303 GDB support for location expressions has been extended to support function
1304 arguments and frame bases. Older versions of GDB could crash when they
1307 * C++ nested types and namespaces
1309 GDB's support for nested types and namespaces in C++ has been
1310 improved, especially if you use the DWARF 2 debugging format. (This
1311 is the default for recent versions of GCC on most platforms.)
1312 Specifically, if you have a class "Inner" defined within a class or
1313 namespace "Outer", then GDB realizes that the class's name is
1314 "Outer::Inner", not simply "Inner". This should greatly reduce the
1315 frequency of complaints about not finding RTTI symbols. In addition,
1316 if you are stopped at inside of a function defined within a namespace,
1317 GDB modifies its name lookup accordingly.
1319 * New native configurations
1321 NetBSD/amd64 x86_64-*-netbsd*
1322 OpenBSD/amd64 x86_64-*-openbsd*
1323 OpenBSD/alpha alpha*-*-openbsd*
1324 OpenBSD/sparc sparc-*-openbsd*
1325 OpenBSD/sparc64 sparc64-*-openbsd*
1327 * New debugging protocols
1329 M32R with SDI protocol m32r-*-elf*
1331 * "set prompt-escape-char" command deleted.
1333 The command "set prompt-escape-char" has been deleted. This command,
1334 and its very obscure effet on GDB's prompt, was never documented,
1335 tested, nor mentioned in the NEWS file.
1337 * OBSOLETE configurations and files
1339 Configurations that have been declared obsolete in this release have
1340 been commented out. Unless there is activity to revive these
1341 configurations, the next release of GDB will have their sources
1342 permanently REMOVED.
1344 Sun 3, running SunOS 3 m68*-*-sunos3*
1345 Sun 3, running SunOS 4 m68*-*-sunos4*
1346 Sun 2, running SunOS 3 m68000-*-sunos3*
1347 Sun 2, running SunOS 4 m68000-*-sunos4*
1348 Motorola 680x0 running LynxOS m68*-*-lynxos*
1349 AT&T 3b1/Unix pc m68*-att-*
1350 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1351 decstation mips-dec-* mips-little-*
1352 riscos mips-*-riscos* mips-*-sysv*
1353 sonymips mips-sony-*
1354 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1356 * REMOVED configurations and files
1358 SGI Irix-4.x mips-sgi-irix4 or iris4
1359 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1360 Z8000 simulator z8k-zilog-none or z8ksim
1361 Matsushita MN10200 w/simulator mn10200-*-*
1362 H8/500 simulator h8500-hitachi-hms or h8500hms
1363 HP/PA running BSD hppa*-*-bsd*
1364 HP/PA running OSF/1 hppa*-*-osf*
1365 HP/PA Pro target hppa*-*-pro*
1366 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1367 386BSD i[3456]86-*-bsd*
1368 Sequent family i[3456]86-sequent-sysv4*
1369 i[3456]86-sequent-sysv*
1370 i[3456]86-sequent-bsd*
1371 SPARC running LynxOS sparc-*-lynxos*
1372 SPARC running SunOS 4 sparc-*-sunos4*
1373 Tsqware Sparclet sparclet-*-*
1374 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1376 *** Changes in GDB 6.0:
1380 Support for debugging the Objective-C programming language has been
1381 integrated into GDB.
1383 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1385 DWARF 2's Call Frame Information makes available compiler generated
1386 information that more exactly describes the program's run-time stack.
1387 By using this information, GDB is able to provide more robust stack
1390 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1391 have been updated to use a new backtrace mechanism which includes
1392 DWARF 2 CFI support.
1396 GDB's remote protocol has been extended to include support for hosted
1397 file I/O (where the remote target uses GDB's file system). See GDB's
1398 remote protocol documentation for details.
1400 * All targets using the new architecture framework.
1402 All of GDB's targets have been updated to use the new internal
1403 architecture framework. The way is now open for future GDB releases
1404 to include cross-architecture native debugging support (i386 on amd64,
1407 * GNU/Linux's Thread Local Storage (TLS)
1409 GDB now includes support for for the GNU/Linux implementation of
1410 per-thread variables.
1412 * GNU/Linux's Native POSIX Thread Library (NPTL)
1414 GDB's thread code has been updated to work with either the new
1415 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1417 * Separate debug info.
1419 GDB, in conjunction with BINUTILS, now supports a mechanism for
1420 automatically loading debug information from a separate file. Instead
1421 of shipping full debug and non-debug versions of system libraries,
1422 system integrators can now instead ship just the stripped libraries
1423 and optional debug files.
1425 * DWARF 2 Location Expressions
1427 DWARF 2 Location Expressions allow the compiler to more completely
1428 describe the location of variables (even in optimized code) to the
1431 GDB now includes preliminary support for location expressions (support
1432 for DW_OP_piece is still missing).
1436 A number of long standing bugs that caused GDB to die while starting a
1437 Java application have been fixed. GDB's Java support is now
1438 considered "useable".
1440 * GNU/Linux support for fork, vfork, and exec.
1442 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1443 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1446 * GDB supports logging output to a file
1448 There are two new commands, "set logging" and "show logging", which can be
1449 used to capture GDB's output to a file.
1451 * The meaning of "detach" has changed for gdbserver
1453 The "detach" command will now resume the application, as documented. To
1454 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1457 * d10v, m68hc11 `regs' command deprecated
1459 The `info registers' command has been updated so that it displays the
1460 registers using a format identical to the old `regs' command.
1464 A new command, "maint set profile on/off", has been added. This command can
1465 be used to enable or disable profiling while running GDB, to profile a
1466 session or a set of commands. In addition there is a new configure switch,
1467 "--enable-profiling", which will cause GDB to be compiled with profiling
1468 data, for more informative profiling results.
1470 * Default MI syntax changed to "mi2".
1472 The default MI (machine interface) syntax, enabled by the command line
1473 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1474 "mi1", can be enabled by specifying the option "-i=mi1".
1476 Support for the original "mi0" syntax (included in GDB 5.0) has been
1479 Fix for gdb/192: removed extraneous space when displaying frame level.
1480 Fix for gdb/672: update changelist is now output in mi list format.
1481 Fix for gdb/702: a -var-assign that updates the value now shows up
1482 in a subsequent -var-update.
1484 * New native configurations.
1486 FreeBSD/amd64 x86_64-*-freebsd*
1488 * Multi-arched targets.
1490 HP/PA HPUX11 hppa*-*-hpux*
1491 Renesas M32R/D w/simulator m32r-*-elf*
1493 * OBSOLETE configurations and files
1495 Configurations that have been declared obsolete in this release have
1496 been commented out. Unless there is activity to revive these
1497 configurations, the next release of GDB will have their sources
1498 permanently REMOVED.
1500 Z8000 simulator z8k-zilog-none or z8ksim
1501 Matsushita MN10200 w/simulator mn10200-*-*
1502 H8/500 simulator h8500-hitachi-hms or h8500hms
1503 HP/PA running BSD hppa*-*-bsd*
1504 HP/PA running OSF/1 hppa*-*-osf*
1505 HP/PA Pro target hppa*-*-pro*
1506 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1507 Sequent family i[3456]86-sequent-sysv4*
1508 i[3456]86-sequent-sysv*
1509 i[3456]86-sequent-bsd*
1510 Tsqware Sparclet sparclet-*-*
1511 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1513 * REMOVED configurations and files
1516 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1517 IBM AIX PS/2 i[3456]86-*-aix
1518 i386 running Mach 3.0 i[3456]86-*-mach3*
1519 i386 running Mach i[3456]86-*-mach*
1520 i386 running OSF/1 i[3456]86-*osf1mk*
1521 HP/Apollo 68k Family m68*-apollo*-sysv*,
1523 m68*-hp-bsd*, m68*-hp-hpux*
1524 Argonaut Risc Chip (ARC) arc-*-*
1525 Mitsubishi D30V d30v-*-*
1526 Fujitsu FR30 fr30-*-elf*
1527 OS/9000 i[34]86-*-os9k
1528 I960 with MON960 i960-*-coff
1530 * MIPS $fp behavior changed
1532 The convenience variable $fp, for the MIPS, now consistently returns
1533 the address of the current frame's base. Previously, depending on the
1534 context, $fp could refer to either $sp or the current frame's base
1535 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1536 The GNU Source-Level Debugger''.
1538 *** Changes in GDB 5.3:
1540 * GNU/Linux shared library multi-threaded performance improved.
1542 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1543 `/proc', in preference to `ptrace' for memory reads. This may result
1544 in an improvement in the start-up time of multi-threaded, shared
1545 library applications when run under GDB. One GDB user writes: ``loads
1546 shared libs like mad''.
1548 * ``gdbserver'' now supports multi-threaded applications on some targets
1550 Support for debugging multi-threaded applications which use
1551 the GNU/Linux LinuxThreads package has been added for
1552 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1553 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1555 * GDB now supports C/C++ preprocessor macros.
1557 GDB now expands preprocessor macro invocations in C/C++ expressions,
1558 and provides various commands for showing macro definitions and how
1561 The new command `macro expand EXPRESSION' expands any macro
1562 invocations in expression, and shows the result.
1564 The new command `show macro MACRO-NAME' shows the definition of the
1565 macro named MACRO-NAME, and where it was defined.
1567 Most compilers don't include information about macros in the debugging
1568 information by default. In GCC 3.1, for example, you need to compile
1569 your program with the options `-gdwarf-2 -g3'. If the macro
1570 information is present in the executable, GDB will read it.
1572 * Multi-arched targets.
1574 DEC Alpha (partial) alpha*-*-*
1575 DEC VAX (partial) vax-*-*
1577 National Semiconductor NS32000 (partial) ns32k-*-*
1578 Motorola 68000 (partial) m68k-*-*
1579 Motorola MCORE mcore-*-*
1583 Fujitsu FRV architecture added by Red Hat frv*-*-*
1586 * New native configurations
1588 Alpha NetBSD alpha*-*-netbsd*
1589 SH NetBSD sh*-*-netbsdelf*
1590 MIPS NetBSD mips*-*-netbsd*
1591 UltraSPARC NetBSD sparc64-*-netbsd*
1593 * OBSOLETE configurations and files
1595 Configurations that have been declared obsolete in this release have
1596 been commented out. Unless there is activity to revive these
1597 configurations, the next release of GDB will have their sources
1598 permanently REMOVED.
1600 Mitsubishi D30V d30v-*-*
1601 OS/9000 i[34]86-*-os9k
1602 IBM AIX PS/2 i[3456]86-*-aix
1603 Fujitsu FR30 fr30-*-elf*
1604 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1605 Argonaut Risc Chip (ARC) arc-*-*
1606 i386 running Mach 3.0 i[3456]86-*-mach3*
1607 i386 running Mach i[3456]86-*-mach*
1608 i386 running OSF/1 i[3456]86-*osf1mk*
1609 HP/Apollo 68k Family m68*-apollo*-sysv*,
1611 m68*-hp-bsd*, m68*-hp-hpux*
1612 I960 with MON960 i960-*-coff
1614 * OBSOLETE languages
1616 CHILL, a Pascal like language used by telecommunications companies.
1618 * REMOVED configurations and files
1620 AMD 29k family via UDI a29k-amd-udi, udi29k
1621 A29K VxWorks a29k-*-vxworks
1622 AMD 29000 embedded, using EBMON a29k-none-none
1623 AMD 29000 embedded with COFF a29k-none-coff
1624 AMD 29000 embedded with a.out a29k-none-aout
1626 testsuite/gdb.hp/gdb.threads-hp/ directory
1628 * New command "set max-user-call-depth <nnn>"
1630 This command allows the user to limit the call depth of user-defined
1631 commands. The default is 1024.
1633 * Changes in FreeBSD/i386 native debugging.
1635 Support for the "generate-core-file" has been added.
1637 * New commands "dump", "append", and "restore".
1639 These commands allow data to be copied from target memory
1640 to a bfd-format or binary file (dump and append), and back
1641 from a file into memory (restore).
1643 * Improved "next/step" support on multi-processor Alpha Tru64.
1645 The previous single-step mechanism could cause unpredictable problems,
1646 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1647 of a software single-step mechanism prevents this.
1649 *** Changes in GDB 5.2.1:
1657 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1658 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1659 Fix, by Joel Brobecker imported from mainline.
1661 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1662 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1663 Fix, by Fred Fish, imported from mainline.
1665 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1666 Surprisingly enough, it works now.
1667 By Michal Ludvig, imported from mainline.
1669 i386 hardware watchpoint support:
1670 avoid misses on second run for some targets.
1671 By Pierre Muller, imported from mainline.
1673 *** Changes in GDB 5.2:
1675 * New command "set trust-readonly-sections on[off]".
1677 This command is a hint that tells gdb that read-only sections
1678 really are read-only (ie. that their contents will not change).
1679 In this mode, gdb will go to the object file rather than the
1680 target to read memory from read-only sections (such as ".text").
1681 This can be a significant performance improvement on some
1682 (notably embedded) targets.
1684 * New command "generate-core-file" (or "gcore").
1686 This new gdb command allows the user to drop a core file of the child
1687 process state at any time. So far it's been implemented only for
1688 GNU/Linux and Solaris, but should be relatively easily ported to other
1689 hosts. Argument is core file name (defaults to core.<pid>).
1691 * New command line option
1693 GDB now accepts --pid or -p followed by a process id.
1695 * Change in command line behavior -- corefiles vs. process ids.
1697 There is a subtle behavior in the way in which GDB handles
1698 command line arguments. The first non-flag argument is always
1699 a program to debug, but the second non-flag argument may either
1700 be a corefile or a process id. Previously, GDB would attempt to
1701 open the second argument as a corefile, and if that failed, would
1702 issue a superfluous error message and then attempt to attach it as
1703 a process. Now, if the second argument begins with a non-digit,
1704 it will be treated as a corefile. If it begins with a digit,
1705 GDB will attempt to attach it as a process, and if no such process
1706 is found, will then attempt to open it as a corefile.
1708 * Changes in ARM configurations.
1710 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1711 configuration is fully multi-arch.
1713 * New native configurations
1715 ARM NetBSD arm*-*-netbsd*
1716 x86 OpenBSD i[3456]86-*-openbsd*
1717 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1718 Sparc64 running FreeBSD sparc64-*-freebsd*
1722 Sanyo XStormy16 xstormy16-elf
1724 * OBSOLETE configurations and files
1726 Configurations that have been declared obsolete in this release have
1727 been commented out. Unless there is activity to revive these
1728 configurations, the next release of GDB will have their sources
1729 permanently REMOVED.
1731 AMD 29k family via UDI a29k-amd-udi, udi29k
1732 A29K VxWorks a29k-*-vxworks
1733 AMD 29000 embedded, using EBMON a29k-none-none
1734 AMD 29000 embedded with COFF a29k-none-coff
1735 AMD 29000 embedded with a.out a29k-none-aout
1737 testsuite/gdb.hp/gdb.threads-hp/ directory
1739 * REMOVED configurations and files
1741 TI TMS320C80 tic80-*-*
1743 PowerPC Solaris powerpcle-*-solaris*
1744 PowerPC Windows NT powerpcle-*-cygwin32
1745 PowerPC Netware powerpc-*-netware*
1746 Harris/CXUX m88k m88*-harris-cxux*
1747 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1748 ns32k-utek-sysv* ns32k-utek-*
1749 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1750 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1751 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1752 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1753 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1755 * Changes to command line processing
1757 The new `--args' feature can be used to specify command-line arguments
1758 for the inferior from gdb's command line.
1760 * Changes to key bindings
1762 There is a new `operate-and-get-next' function bound to `C-o'.
1764 *** Changes in GDB 5.1.1
1766 Fix compile problem on DJGPP.
1768 Fix a problem with floating-point registers on the i386 being
1771 Fix to stop GDB crashing on .debug_str debug info.
1773 Numerous documentation fixes.
1775 Numerous testsuite fixes.
1777 *** Changes in GDB 5.1:
1779 * New native configurations
1781 Alpha FreeBSD alpha*-*-freebsd*
1782 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1783 MIPS GNU/Linux mips*-*-linux*
1784 MIPS SGI Irix 6.x mips*-sgi-irix6*
1785 ia64 AIX ia64-*-aix*
1786 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1790 Motorola 68HC11 and 68HC12 m68hc11-elf
1792 UltraSparc running GNU/Linux sparc64-*-linux*
1794 * OBSOLETE configurations and files
1796 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1797 Harris/CXUX m88k m88*-harris-cxux*
1798 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1799 ns32k-utek-sysv* ns32k-utek-*
1800 TI TMS320C80 tic80-*-*
1802 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1803 PowerPC Solaris powerpcle-*-solaris*
1804 PowerPC Windows NT powerpcle-*-cygwin32
1805 PowerPC Netware powerpc-*-netware*
1806 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1807 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1808 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1809 Apple Macintosh (MPW) host N/A
1811 stuff.c (Program to stuff files into a specially prepared space in kdb)
1812 kdb-start.c (Main loop for the standalone kernel debugger)
1814 Configurations that have been declared obsolete in this release have
1815 been commented out. Unless there is activity to revive these
1816 configurations, the next release of GDB will have their sources
1817 permanently REMOVED.
1819 * REMOVED configurations and files
1821 Altos 3068 m68*-altos-*
1822 Convex c1-*-*, c2-*-*
1824 ARM RISCix arm-*-* (as host)
1828 * GDB has been converted to ISO C.
1830 GDB's source code has been converted to ISO C. In particular, the
1831 sources are fully protoized, and rely on standard headers being
1836 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1838 * The MI enabled by default.
1840 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1841 revised and enabled by default. Packages which use GDB as a debugging
1842 engine behind a UI or another front end are encouraged to switch to
1843 using the GDB/MI interface, instead of the old annotations interface
1844 which is now deprecated.
1846 * Support for debugging Pascal programs.
1848 GDB now includes support for debugging Pascal programs. The following
1849 main features are supported:
1851 - Pascal-specific data types such as sets;
1853 - automatic recognition of Pascal sources based on file-name
1856 - Pascal-style display of data types, variables, and functions;
1858 - a Pascal expression parser.
1860 However, some important features are not yet supported.
1862 - Pascal string operations are not supported at all;
1864 - there are some problems with boolean types;
1866 - Pascal type hexadecimal constants are not supported
1867 because they conflict with the internal variables format;
1869 - support for Pascal objects and classes is not full yet;
1871 - unlike Pascal, GDB is case-sensitive for symbol names.
1873 * Changes in completion.
1875 Commands such as `shell', `run' and `set args', which pass arguments
1876 to inferior programs, now complete on file names, similar to what
1877 users expect at the shell prompt.
1879 Commands which accept locations, such as `disassemble', `print',
1880 `breakpoint', `until', etc. now complete on filenames as well as
1881 program symbols. Thus, if you type "break foob TAB", and the source
1882 files linked into the programs include `foobar.c', that file name will
1883 be one of the candidates for completion. However, file names are not
1884 considered for completion after you typed a colon that delimits a file
1885 name from a name of a function in that file, as in "break foo.c:bar".
1887 `set demangle-style' completes on available demangling styles.
1889 * New platform-independent commands:
1891 It is now possible to define a post-hook for a command as well as a
1892 hook that runs before the command. For more details, see the
1893 documentation of `hookpost' in the GDB manual.
1895 * Changes in GNU/Linux native debugging.
1897 Support for debugging multi-threaded programs has been completely
1898 revised for all platforms except m68k and sparc. You can now debug as
1899 many threads as your system allows you to have.
1901 Attach/detach is supported for multi-threaded programs.
1903 Support for SSE registers was added for x86. This doesn't work for
1904 multi-threaded programs though.
1906 * Changes in MIPS configurations.
1908 Multi-arch support is enabled for all MIPS configurations.
1910 GDB can now be built as native debugger on SGI Irix 6.x systems for
1911 debugging n32 executables. (Debugging 64-bit executables is not yet
1914 * Unified support for hardware watchpoints in all x86 configurations.
1916 Most (if not all) native x86 configurations support hardware-assisted
1917 breakpoints and watchpoints in a unified manner. This support
1918 implements debug register sharing between watchpoints, which allows to
1919 put a virtually infinite number of watchpoints on the same address,
1920 and also supports watching regions up to 16 bytes with several debug
1923 The new maintenance command `maintenance show-debug-regs' toggles
1924 debugging print-outs in functions that insert, remove, and test
1925 watchpoints and hardware breakpoints.
1927 * Changes in the DJGPP native configuration.
1929 New command ``info dos sysinfo'' displays assorted information about
1930 the CPU, OS, memory, and DPMI server.
1932 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1933 display information about segment descriptors stored in GDT, LDT, and
1936 New commands ``info dos pde'' and ``info dos pte'' display entries
1937 from Page Directory and Page Tables (for now works with CWSDPMI only).
1938 New command ``info dos address-pte'' displays the Page Table entry for
1939 a given linear address.
1941 GDB can now pass command lines longer than 126 characters to the
1942 program being debugged (requires an update to the libdbg.a library
1943 which is part of the DJGPP development kit).
1945 DWARF2 debug info is now supported.
1947 It is now possible to `step' and `next' through calls to `longjmp'.
1949 * Changes in documentation.
1951 All GDB documentation was converted to GFDL, the GNU Free
1952 Documentation License.
1954 Tracepoints-related commands are now fully documented in the GDB
1957 TUI, the Text-mode User Interface, is now documented in the manual.
1959 Tracepoints-related commands are now fully documented in the GDB
1962 The "GDB Internals" manual now has an index. It also includes
1963 documentation of `ui_out' functions, GDB coding standards, x86
1964 hardware watchpoints, and memory region attributes.
1966 * GDB's version number moved to ``version.in''
1968 The Makefile variable VERSION has been replaced by the file
1969 ``version.in''. People creating GDB distributions should update the
1970 contents of this file.
1974 GUD support is now a standard part of the EMACS distribution.
1976 *** Changes in GDB 5.0:
1978 * Improved support for debugging FP programs on x86 targets
1980 Unified and much-improved support for debugging floating-point
1981 programs on all x86 targets. In particular, ``info float'' now
1982 displays the FP registers in the same format on all x86 targets, with
1983 greater level of detail.
1985 * Improvements and bugfixes in hardware-assisted watchpoints
1987 It is now possible to watch array elements, struct members, and
1988 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1989 on x86 targets no longer erroneously trigger when the address is
1992 * Improvements in the native DJGPP version of GDB
1994 The distribution now includes all the scripts and auxiliary files
1995 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1996 machines ``out of the box''.
1998 The DJGPP version can now debug programs that use signals. It is
1999 possible to catch signals that happened in the debuggee, deliver
2000 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2001 would kill the program being debugged.) Programs that hook hardware
2002 interrupts (keyboard, timer, etc.) can also be debugged.
2004 It is now possible to debug DJGPP programs that redirect their
2005 standard handles or switch them to raw (as opposed to cooked) mode, or
2006 even close them. The command ``run < foo > bar'' works as expected,
2007 and ``info terminal'' reports useful information about the debuggee's
2008 terminal, including raw/cooked mode, redirection, etc.
2010 The DJGPP version now uses termios functions for console I/O, which
2011 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2014 DOS-style file names with drive letters are now fully supported by
2017 It is now possible to debug DJGPP programs that switch their working
2018 directory. It is also possible to rerun the debuggee any number of
2019 times without restarting GDB; thus, you can use the same setup,
2020 breakpoints, etc. for many debugging sessions.
2022 * New native configurations
2024 ARM GNU/Linux arm*-*-linux*
2025 PowerPC GNU/Linux powerpc-*-linux*
2029 Motorola MCore mcore-*-*
2030 x86 VxWorks i[3456]86-*-vxworks*
2031 PowerPC VxWorks powerpc-*-vxworks*
2032 TI TMS320C80 tic80-*-*
2034 * OBSOLETE configurations
2036 Altos 3068 m68*-altos-*
2037 Convex c1-*-*, c2-*-*
2039 ARM RISCix arm-*-* (as host)
2042 Configurations that have been declared obsolete will be commented out,
2043 but the code will be left in place. If there is no activity to revive
2044 these configurations before the next release of GDB, the sources will
2045 be permanently REMOVED.
2047 * Gould support removed
2049 Support for the Gould PowerNode and NP1 has been removed.
2051 * New features for SVR4
2053 On SVR4 native platforms (such as Solaris), if you attach to a process
2054 without first loading a symbol file, GDB will now attempt to locate and
2055 load symbols from the running process's executable file.
2057 * Many C++ enhancements
2059 C++ support has been greatly improved. Overload resolution now works properly
2060 in almost all cases. RTTI support is on the way.
2062 * Remote targets can connect to a sub-program
2064 A popen(3) style serial-device has been added. This device starts a
2065 sub-process (such as a stand-alone simulator) and then communicates
2066 with that. The sub-program to run is specified using the syntax
2067 ``|<program> <args>'' vis:
2069 (gdb) set remotedebug 1
2070 (gdb) target extended-remote |mn10300-elf-sim program-args
2072 * MIPS 64 remote protocol
2074 A long standing bug in the mips64 remote protocol where by GDB
2075 expected certain 32 bit registers (ex SR) to be transfered as 32
2076 instead of 64 bits has been fixed.
2078 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2079 added to provide backward compatibility with older versions of GDB.
2081 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2083 The command ``set remotebinarydownload'' command has been replaced by
2084 ``set remote X-packet''. Other commands in ``set remote'' family
2085 include ``set remote P-packet''.
2087 * Breakpoint commands accept ranges.
2089 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2090 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2091 ``tracepoint passcount'' also accepts a range of tracepoints.
2093 * ``apropos'' command added.
2095 The ``apropos'' command searches through command names and
2096 documentation strings, printing out matches, making it much easier to
2097 try to find a command that does what you are looking for.
2101 A new machine oriented interface (MI) has been added to GDB. This
2102 interface is designed for debug environments running GDB as a separate
2103 process. This is part of the long term libGDB project. See the
2104 "GDB/MI" chapter of the GDB manual for further information. It can be
2105 enabled by configuring with:
2107 .../configure --enable-gdbmi
2109 *** Changes in GDB-4.18:
2111 * New native configurations
2113 HP-UX 10.20 hppa*-*-hpux10.20
2114 HP-UX 11.x hppa*-*-hpux11.0*
2115 M68K GNU/Linux m68*-*-linux*
2119 Fujitsu FR30 fr30-*-elf*
2120 Intel StrongARM strongarm-*-*
2121 Mitsubishi D30V d30v-*-*
2123 * OBSOLETE configurations
2125 Gould PowerNode, NP1 np1-*-*, pn-*-*
2127 Configurations that have been declared obsolete will be commented out,
2128 but the code will be left in place. If there is no activity to revive
2129 these configurations before the next release of GDB, the sources will
2130 be permanently REMOVED.
2134 As a compatibility experiment, GDB's source files buildsym.h and
2135 buildsym.c have been converted to pure standard C, no longer
2136 containing any K&R compatibility code. We believe that all systems in
2137 use today either come with a standard C compiler, or have a GCC port
2138 available. If this is not true, please report the affected
2139 configuration to bug-gdb@gnu.org immediately. See the README file for
2140 information about getting a standard C compiler if you don't have one
2145 GDB now uses readline 2.2.
2147 * set extension-language
2149 You can now control the mapping between filename extensions and source
2150 languages by using the `set extension-language' command. For instance,
2151 you can ask GDB to treat .c files as C++ by saying
2152 set extension-language .c c++
2153 The command `info extensions' lists all of the recognized extensions
2154 and their associated languages.
2156 * Setting processor type for PowerPC and RS/6000
2158 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2159 you can use the `set processor' command to specify what variant of the
2160 PowerPC family you are debugging. The command
2164 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2165 following PowerPC and RS6000 variants:
2167 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2168 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2170 403GC IBM PowerPC 403GC
2171 505 Motorola PowerPC 505
2172 860 Motorola PowerPC 860 or 850
2173 601 Motorola PowerPC 601
2174 602 Motorola PowerPC 602
2175 603 Motorola/IBM PowerPC 603 or 603e
2176 604 Motorola PowerPC 604 or 604e
2177 750 Motorola/IBM PowerPC 750 or 750
2179 At the moment, this command just tells GDB what to name the
2180 special-purpose processor registers. Since almost all the affected
2181 registers are inaccessible to user-level programs, this command is
2182 only useful for remote debugging in its present form.
2186 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2187 more extensive support for HP-UX. Added features include shared
2188 library support, kernel threads and hardware watchpoints for 11.00,
2189 support for HP's ANSI C and C++ compilers, and a compatibility mode
2190 for xdb and dbx commands.
2194 HP's donation includes the new concept of catchpoints, which is a
2195 generalization of the old catch command. On HP-UX, it is now possible
2196 to catch exec, fork, and vfork, as well as library loading.
2198 This means that the existing catch command has changed; its first
2199 argument now specifies the type of catch to be set up. See the
2200 output of "help catch" for a list of catchpoint types.
2202 * Debugging across forks
2204 On HP-UX, you can choose which process to debug when a fork() happens
2209 HP has donated a curses-based terminal user interface (TUI). To get
2210 it, build with --enable-tui. Although this can be enabled for any
2211 configuration, at present it only works for native HP debugging.
2213 * GDB remote protocol additions
2215 A new protocol packet 'X' that writes binary data is now available.
2216 Default behavior is to try 'X', then drop back to 'M' if the stub
2217 fails to respond. The settable variable `remotebinarydownload'
2218 allows explicit control over the use of 'X'.
2220 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2221 full 64-bit address. The command
2223 set remoteaddresssize 32
2225 can be used to revert to the old behaviour. For existing remote stubs
2226 the change should not be noticed, as the additional address information
2229 In order to assist in debugging stubs, you may use the maintenance
2230 command `packet' to send any text string to the stub. For instance,
2232 maint packet heythere
2234 sends the packet "$heythere#<checksum>". Note that it is very easy to
2235 disrupt a debugging session by sending the wrong packet at the wrong
2238 The compare-sections command allows you to compare section data on the
2239 target to what is in the executable file without uploading or
2240 downloading, by comparing CRC checksums.
2242 * Tracing can collect general expressions
2244 You may now collect general expressions at tracepoints. This requires
2245 further additions to the target-side stub; see tracepoint.c and
2246 doc/agentexpr.texi for further details.
2248 * mask-address variable for Mips
2250 For Mips targets, you may control the zeroing of the upper 32 bits of
2251 a 64-bit address by entering `set mask-address on'. This is mainly
2252 of interest to users of embedded R4xxx and R5xxx processors.
2254 * Higher serial baud rates
2256 GDB's serial code now allows you to specify baud rates 57600, 115200,
2257 230400, and 460800 baud. (Note that your host system may not be able
2258 to achieve all of these rates.)
2262 The i960 configuration now includes an initial implementation of a
2263 builtin simulator, contributed by Jim Wilson.
2266 *** Changes in GDB-4.17:
2268 * New native configurations
2270 Alpha GNU/Linux alpha*-*-linux*
2271 Unixware 2.x i[3456]86-unixware2*
2272 Irix 6.x mips*-sgi-irix6*
2273 PowerPC GNU/Linux powerpc-*-linux*
2274 PowerPC Solaris powerpcle-*-solaris*
2275 Sparc GNU/Linux sparc-*-linux*
2276 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2280 Argonaut Risc Chip (ARC) arc-*-*
2281 Hitachi H8/300S h8300*-*-*
2282 Matsushita MN10200 w/simulator mn10200-*-*
2283 Matsushita MN10300 w/simulator mn10300-*-*
2284 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2285 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2286 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2287 Mitsubishi D10V w/simulator d10v-*-*
2288 Mitsubishi M32R/D w/simulator m32r-*-elf*
2289 Tsqware Sparclet sparclet-*-*
2290 NEC V850 w/simulator v850-*-*
2292 * New debugging protocols
2294 ARM with RDI protocol arm*-*-*
2295 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2296 DDB and LSI variants of PMON protocol mips*-*-*
2297 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2298 PowerPC with SDS protocol powerpc{,le}-*-eabi
2299 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2303 All configurations can now understand and use the DWARF 2 debugging
2304 format. The choice is automatic, if the symbol file contains DWARF 2
2309 GDB now includes basic Java language support. This support is
2310 only useful with Java compilers that produce native machine code.
2312 * solib-absolute-prefix and solib-search-path
2314 For SunOS and SVR4 shared libraries, you may now set the prefix for
2315 loading absolute shared library symbol files, and the search path for
2316 locating non-absolute shared library symbol files.
2318 * Live range splitting
2320 GDB can now effectively debug code for which GCC has performed live
2321 range splitting as part of its optimization. See gdb/doc/LRS for
2322 more details on the expected format of the stabs information.
2326 GDB's support for the GNU Hurd, including thread debugging, has been
2327 updated to work with current versions of the Hurd.
2331 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2332 instruction set. ARM GDB automatically detects when Thumb
2333 instructions are in use, and adjusts disassembly and backtracing
2338 GDB's MIPS target configurations now handle the MIP16 16-bit
2343 GDB now includes support for overlays; if an executable has been
2344 linked such that multiple sections are based at the same address, GDB
2345 will decide which section to use for symbolic info. You can choose to
2346 control the decision manually, using overlay commands, or implement
2347 additional target-side support and use "overlay load-target" to bring
2348 in the overlay mapping. Do "help overlay" for more detail.
2352 The command "info symbol <address>" displays information about
2353 the symbol at the specified address.
2357 The standard remote protocol now includes an extension that allows
2358 asynchronous collection and display of trace data. This requires
2359 extensive support in the target-side debugging stub. Tracing mode
2360 includes a new interaction mode in GDB and new commands: see the
2361 file tracepoint.c for more details.
2365 Configurations for embedded MIPS now include a simulator contributed
2366 by Cygnus Solutions. The simulator supports the instruction sets
2367 of most MIPS variants.
2371 Sparc configurations may now include the ERC32 simulator contributed
2372 by the European Space Agency. The simulator is not built into
2373 Sparc targets by default; configure with --enable-sim to include it.
2377 For target configurations that may include multiple variants of a
2378 basic architecture (such as MIPS and SH), you may now set the
2379 architecture explicitly. "set arch" sets, "info arch" lists
2380 the possible architectures.
2382 *** Changes in GDB-4.16:
2384 * New native configurations
2386 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2387 M68K NetBSD m68k-*-netbsd*
2388 PowerPC AIX 4.x powerpc-*-aix*
2389 PowerPC MacOS powerpc-*-macos*
2390 PowerPC Windows NT powerpcle-*-cygwin32
2391 RS/6000 AIX 4.x rs6000-*-aix4*
2395 ARM with RDP protocol arm-*-*
2396 I960 with MON960 i960-*-coff
2397 MIPS VxWorks mips*-*-vxworks*
2398 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2399 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2401 Matra Sparclet sparclet-*-*
2405 The powerpc-eabi configuration now includes the PSIM simulator,
2406 contributed by Andrew Cagney, with assistance from Mike Meissner.
2407 PSIM is a very elaborate model of the PowerPC, including not only
2408 basic instruction set execution, but also details of execution unit
2409 performance and I/O hardware. See sim/ppc/README for more details.
2413 GDB now works with Solaris 2.5.
2415 * Windows 95/NT native
2417 GDB will now work as a native debugger on Windows 95 and Windows NT.
2418 To build it from source, you must use the "gnu-win32" environment,
2419 which uses a DLL to emulate enough of Unix to run the GNU tools.
2420 Further information, binaries, and sources are available at
2421 ftp.cygnus.com, under pub/gnu-win32.
2423 * dont-repeat command
2425 If a user-defined command includes the command `dont-repeat', then the
2426 command will not be repeated if the user just types return. This is
2427 useful if the command is time-consuming to run, so that accidental
2428 extra keystrokes don't run the same command many times.
2430 * Send break instead of ^C
2432 The standard remote protocol now includes an option to send a break
2433 rather than a ^C to the target in order to interrupt it. By default,
2434 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2436 * Remote protocol timeout
2438 The standard remote protocol includes a new variable `remotetimeout'
2439 that allows you to set the number of seconds before GDB gives up trying
2440 to read from the target. The default value is 2.
2442 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2444 By default GDB will automatically keep track of objects as they are
2445 loaded and unloaded by the dynamic linker. By using the command `set
2446 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2447 when shared library events occur, thus allowing you to set breakpoints
2448 in shared libraries which are explicitly loaded by the inferior.
2450 Note this feature does not work on hpux8. On hpux9 you must link
2451 /usr/lib/end.o into your program. This feature should work
2452 automatically on hpux10.
2454 * Irix 5.x hardware watchpoint support
2456 Irix 5 configurations now support the use of hardware watchpoints.
2458 * Mips protocol "SYN garbage limit"
2460 When debugging a Mips target using the `target mips' protocol, you
2461 may set the number of characters that GDB will ignore by setting
2462 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2463 every character. The default value is 1050.
2465 * Recording and replaying remote debug sessions
2467 If you set `remotelogfile' to the name of a file, gdb will write to it
2468 a recording of a remote debug session. This recording may then be
2469 replayed back to gdb using "gdbreplay". See gdbserver/README for
2470 details. This is useful when you have a problem with GDB while doing
2471 remote debugging; you can make a recording of the session and send it
2472 to someone else, who can then recreate the problem.
2474 * Speedups for remote debugging
2476 GDB includes speedups for downloading and stepping MIPS systems using
2477 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2478 and more efficient S-record downloading.
2480 * Memory use reductions and statistics collection
2482 GDB now uses less memory and reports statistics about memory usage.
2483 Try the `maint print statistics' command, for example.
2485 *** Changes in GDB-4.15:
2487 * Psymtabs for XCOFF
2489 The symbol reader for AIX GDB now uses partial symbol tables. This
2490 can greatly improve startup time, especially for large executables.
2492 * Remote targets use caching
2494 Remote targets now use a data cache to speed up communication with the
2495 remote side. The data cache could lead to incorrect results because
2496 it doesn't know about volatile variables, thus making it impossible to
2497 debug targets which use memory mapped I/O devices. `set remotecache
2498 off' turns the the data cache off.
2500 * Remote targets may have threads
2502 The standard remote protocol now includes support for multiple threads
2503 in the target system, using new protocol commands 'H' and 'T'. See
2504 gdb/remote.c for details.
2508 If GDB is configured with `--enable-netrom', then it will include
2509 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2510 acts as though it is a bank of ROM on the target board, but you can
2511 write into it over the network. GDB's support consists only of
2512 support for fast loading into the emulated ROM; to debug, you must use
2513 another protocol, such as standard remote protocol. The usual
2514 sequence is something like
2516 target nrom <netrom-hostname>
2518 target remote <netrom-hostname>:1235
2522 GDB now includes support for the Apple Macintosh, as a host only. It
2523 may be run as either an MPW tool or as a standalone application, and
2524 it can debug through the serial port. All the usual GDB commands are
2525 available, but to the target command, you must supply "serial" as the
2526 device type instead of "/dev/ttyXX". See mpw-README in the main
2527 directory for more information on how to build. The MPW configuration
2528 scripts */mpw-config.in support only a few targets, and only the
2529 mips-idt-ecoff target has been tested.
2533 GDB configuration now uses autoconf. This is not user-visible,
2534 but does simplify configuration and building.
2538 GDB now supports hpux10.
2540 *** Changes in GDB-4.14:
2542 * New native configurations
2544 x86 FreeBSD i[345]86-*-freebsd
2545 x86 NetBSD i[345]86-*-netbsd
2546 NS32k NetBSD ns32k-*-netbsd
2547 Sparc NetBSD sparc-*-netbsd
2551 A29K VxWorks a29k-*-vxworks
2552 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2553 CPU32 EST-300 emulator m68*-*-est*
2554 PowerPC ELF powerpc-*-elf
2557 * Alpha OSF/1 support for procfs
2559 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2560 possible to attach to running processes. As the mounting of the /proc
2561 filesystem is optional on the Alpha, GDB automatically determines
2562 the availability of /proc during startup. This can lead to problems
2563 if /proc is unmounted after GDB has been started.
2565 * Arguments to user-defined commands
2567 User commands may accept up to 10 arguments separated by whitespace.
2568 Arguments are accessed within the user command via $arg0..$arg9. A
2571 print $arg0 + $arg1 + $arg2
2573 To execute the command use:
2576 Defines the command "adder" which prints the sum of its three arguments.
2577 Note the arguments are text substitutions, so they may reference variables,
2578 use complex expressions, or even perform inferior function calls.
2580 * New `if' and `while' commands
2582 This makes it possible to write more sophisticated user-defined
2583 commands. Both commands take a single argument, which is the
2584 expression to evaluate, and must be followed by the commands to
2585 execute, one per line, if the expression is nonzero, the list being
2586 terminated by the word `end'. The `if' command list may include an
2587 `else' word, which causes the following commands to be executed only
2588 if the expression is zero.
2590 * Fortran source language mode
2592 GDB now includes partial support for Fortran 77. It will recognize
2593 Fortran programs and can evaluate a subset of Fortran expressions, but
2594 variables and functions may not be handled correctly. GDB will work
2595 with G77, but does not yet know much about symbols emitted by other
2598 * Better HPUX support
2600 Most debugging facilities now work on dynamic executables for HPPAs
2601 running hpux9 or later. You can attach to running dynamically linked
2602 processes, but by default the dynamic libraries will be read-only, so
2603 for instance you won't be able to put breakpoints in them. To change
2604 that behavior do the following before running the program:
2610 This will cause the libraries to be mapped private and read-write.
2611 To revert to the normal behavior, do this:
2617 You cannot set breakpoints or examine data in the library until after
2618 the library is loaded if the function/data symbols do not have
2621 GDB can now also read debug symbols produced by the HP C compiler on
2622 HPPAs (sorry, no C++, Fortran or 68k support).
2624 * Target byte order now dynamically selectable
2626 You can choose which byte order to use with a target system, via the
2627 commands "set endian big" and "set endian little", and you can see the
2628 current setting by using "show endian". You can also give the command
2629 "set endian auto", in which case GDB will use the byte order
2630 associated with the executable. Currently, only embedded MIPS
2631 configurations support dynamic selection of target byte order.
2633 * New DOS host serial code
2635 This version uses DPMI interrupts to handle buffered I/O, so you
2636 no longer need to run asynctsr when debugging boards connected to
2639 *** Changes in GDB-4.13:
2641 * New "complete" command
2643 This lists all the possible completions for the rest of the line, if it
2644 were to be given as a command itself. This is intended for use by emacs.
2646 * Trailing space optional in prompt
2648 "set prompt" no longer adds a space for you after the prompt you set. This
2649 allows you to set a prompt which ends in a space or one that does not.
2651 * Breakpoint hit counts
2653 "info break" now displays a count of the number of times the breakpoint
2654 has been hit. This is especially useful in conjunction with "ignore"; you
2655 can ignore a large number of breakpoint hits, look at the breakpoint info
2656 to see how many times the breakpoint was hit, then run again, ignoring one
2657 less than that number, and this will get you quickly to the last hit of
2660 * Ability to stop printing at NULL character
2662 "set print null-stop" will cause GDB to stop printing the characters of
2663 an array when the first NULL is encountered. This is useful when large
2664 arrays actually contain only short strings.
2666 * Shared library breakpoints
2668 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2669 breakpoints in shared libraries before the executable is run.
2671 * Hardware watchpoints
2673 There is a new hardware breakpoint for the watch command for sparclite
2674 targets. See gdb/sparclite/hw_breakpoint.note.
2676 Hardware watchpoints are also now supported under GNU/Linux.
2680 Annotations have been added. These are for use with graphical interfaces,
2681 and are still experimental. Currently only gdba.el uses these.
2683 * Improved Irix 5 support
2685 GDB now works properly with Irix 5.2.
2687 * Improved HPPA support
2689 GDB now works properly with the latest GCC and GAS.
2691 * New native configurations
2693 Sequent PTX4 i[34]86-sequent-ptx4
2694 HPPA running OSF/1 hppa*-*-osf*
2695 Atari TT running SVR4 m68*-*-sysv4*
2696 RS/6000 LynxOS rs6000-*-lynxos*
2700 OS/9000 i[34]86-*-os9k
2701 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2704 * Hitachi SH7000 and E7000-PC ICE support
2706 There is now support for communicating with the Hitachi E7000-PC ICE.
2707 This is available automatically when GDB is configured for the SH.
2711 As usual, a variety of small fixes and improvements, both generic
2712 and configuration-specific. See the ChangeLog for more detail.
2714 *** Changes in GDB-4.12:
2716 * Irix 5 is now supported
2720 GDB-4.12 on the HPPA has a number of changes which make it unable
2721 to debug the output from the currently released versions of GCC and
2722 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2723 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2724 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2727 *** Changes in GDB-4.11:
2729 * User visible changes:
2733 The "set remotedebug" option is now consistent between the mips remote
2734 target, remote targets using the gdb-specific protocol, UDI (AMD's
2735 debug protocol for the 29k) and the 88k bug monitor. It is now an
2736 integer specifying a debug level (normally 0 or 1, but 2 means more
2737 debugging info for the mips target).
2739 * DEC Alpha native support
2741 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2742 debug info, but GDB works fairly well with the DEC compiler and should
2743 work with a future GCC release. See the README file for a few
2744 Alpha-specific notes.
2746 * Preliminary thread implementation
2748 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2750 * LynxOS native and target support for 386
2752 This release has been hosted on LynxOS 2.2, and also can be configured
2753 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2756 * Improvements in C++ mangling/demangling.
2758 This release has much better g++ debugging, specifically in name
2759 mangling/demangling, virtual function calls, print virtual table,
2760 call methods, ...etc.
2762 *** Changes in GDB-4.10:
2764 * User visible changes:
2766 Remote debugging using the GDB-specific (`target remote') protocol now
2767 supports the `load' command. This is only useful if you have some
2768 other way of getting the stub to the target system, and you can put it
2769 somewhere in memory where it won't get clobbered by the download.
2771 Filename completion now works.
2773 When run under emacs mode, the "info line" command now causes the
2774 arrow to point to the line specified. Also, "info line" prints
2775 addresses in symbolic form (as well as hex).
2777 All vxworks based targets now support a user settable option, called
2778 vxworks-timeout. This option represents the number of seconds gdb
2779 should wait for responses to rpc's. You might want to use this if
2780 your vxworks target is, perhaps, a slow software simulator or happens
2781 to be on the far side of a thin network line.
2785 This release contains support for using a DEC alpha as a GDB host for
2786 cross debugging. Native alpha debugging is not supported yet.
2789 *** Changes in GDB-4.9:
2793 This is the first GDB release which is accompanied by a matching testsuite.
2794 The testsuite requires installation of dejagnu, which should be available
2795 via ftp from most sites that carry GNU software.
2799 'Cfront' style demangling has had its name changed to 'ARM' style, to
2800 emphasize that it was written from the specifications in the C++ Annotated
2801 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2802 disclaimers, it still generated too much confusion with users attempting to
2803 use gdb with AT&T cfront.
2807 GDB now uses a standard remote interface to a simulator library.
2808 So far, the library contains simulators for the Zilog Z8001/2, the
2809 Hitachi H8/300, H8/500 and Super-H.
2811 * New targets supported
2813 H8/300 simulator h8300-hitachi-hms or h8300hms
2814 H8/500 simulator h8500-hitachi-hms or h8500hms
2815 SH simulator sh-hitachi-hms or sh
2816 Z8000 simulator z8k-zilog-none or z8ksim
2817 IDT MIPS board over serial line mips-idt-ecoff
2819 Cross-debugging to GO32 targets is supported. It requires a custom
2820 version of the i386-stub.c module which is integrated with the
2821 GO32 memory extender.
2823 * New remote protocols
2825 MIPS remote debugging protocol.
2827 * New source languages supported
2829 This version includes preliminary support for Chill, a Pascal like language
2830 used by telecommunications companies. Chill support is also being integrated
2831 into the GNU compiler, but we don't know when it will be publically available.
2834 *** Changes in GDB-4.8:
2836 * HP Precision Architecture supported
2838 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2839 version of this support was available as a set of patches from the
2840 University of Utah. GDB does not support debugging of programs
2841 compiled with the HP compiler, because HP will not document their file
2842 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2843 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2845 Many problems in the preliminary version have been fixed.
2847 * Faster and better demangling
2849 We have improved template demangling and fixed numerous bugs in the GNU style
2850 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2851 character types (wchar_t) are now supported. Demangling of each symbol is now
2852 only done once, and is cached when the symbol table for a file is read in.
2853 This results in a small increase in memory usage for C programs, a moderate
2854 increase in memory usage for C++ programs, and a fantastic speedup in
2857 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2858 from the specifications in the Annotated Reference Manual, which AT&T's
2859 compiler does not actually implement.
2861 * G++ multiple inheritance compiler problem
2863 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2864 inheritance lattices was reworked to properly discover ambiguities. We
2865 recently found an example which causes this new algorithm to fail in a
2866 very subtle way, producing bad debug information for those classes.
2867 The file 'gcc.patch' (in this directory) can be applied to gcc to
2868 circumvent the problem. A future GCC release will contain a complete
2871 The previous G++ debug info problem (mentioned below for the gdb-4.7
2872 release) is fixed in gcc version 2.3.2.
2874 * Improved configure script
2876 The `configure' script will now attempt to guess your system type if
2877 you don't supply a host system type. The old scheme of supplying a
2878 host system triplet is preferable over using this. All the magic is
2879 done in the new `config.guess' script. Examine it for details.
2881 We have also brought our configure script much more in line with the FSF's
2882 version. It now supports the --with-xxx options. In particular,
2883 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2884 The resulting GDB will not be able to read arbitrary object file formats --
2885 only the format ``expected'' to be used on the configured target system.
2886 We hope to make this the default in a future release.
2888 * Documentation improvements
2890 There's new internal documentation on how to modify GDB, and how to
2891 produce clean changes to the code. We implore people to read it
2892 before submitting changes.
2894 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2895 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2896 `info' files are also provided. To build `info' files from scratch,
2897 you will need the latest `makeinfo' release, which will be available in
2898 a future texinfo-X.Y release.
2900 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2901 We're not sure exactly which versions have this problem, but it has
2902 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2903 or better. If that isn't possible, there is a patch in
2904 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2905 around this problem.
2909 GDB now supports array constants that can be used in expressions typed in by
2910 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2911 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2914 The new directory `gdb/sparclite' contains a program that demonstrates
2915 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2917 * New native hosts supported
2919 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2920 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2922 * New targets supported
2924 AMD 29k family via UDI a29k-amd-udi or udi29k
2926 * New file formats supported
2928 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2929 HPUX core files, and SCO 3.2v2 core files.
2933 Attaching to processes now works again; thanks for the many bug reports.
2935 We have also stomped on a bunch of core dumps caused by
2936 printf_filtered("%s") problems.
2938 We eliminated a copyright problem on the rpc and ptrace header files
2939 for VxWorks, which was discovered at the last minute during the 4.7
2940 release. You should now be able to build a VxWorks GDB.
2942 You can now interrupt gdb while an attached process is running. This
2943 will cause the attached process to stop, and give control back to GDB.
2945 We fixed problems caused by using too many file descriptors
2946 for reading symbols from object files and libraries. This was
2947 especially a problem for programs that used many (~100) shared
2950 The `step' command now only enters a subroutine if there is line number
2951 information for the subroutine. Otherwise it acts like the `next'
2952 command. Previously, `step' would enter subroutines if there was
2953 any debugging information about the routine. This avoids problems
2954 when using `cc -g1' on MIPS machines.
2956 * Internal improvements
2958 GDB's internal interfaces have been improved to make it easier to support
2959 debugging of multiple languages in the future.
2961 GDB now uses a common structure for symbol information internally.
2962 Minimal symbols (derived from linkage symbols in object files), partial
2963 symbols (from a quick scan of debug information), and full symbols
2964 contain a common subset of information, making it easier to write
2965 shared code that handles any of them.
2967 * New command line options
2969 We now accept --silent as an alias for --quiet.
2973 The memory-mapped-malloc library is now licensed under the GNU Library
2974 General Public License.
2976 *** Changes in GDB-4.7:
2978 * Host/native/target split
2980 GDB has had some major internal surgery to untangle the support for
2981 hosts and remote targets. Now, when you configure GDB for a remote
2982 target, it will no longer load in all of the support for debugging
2983 local programs on the host. When fully completed and tested, this will
2984 ensure that arbitrary host/target combinations are possible.
2986 The primary conceptual shift is to separate the non-portable code in
2987 GDB into three categories. Host specific code is required any time GDB
2988 is compiled on that host, regardless of the target. Target specific
2989 code relates to the peculiarities of the target, but can be compiled on
2990 any host. Native specific code is everything else: it can only be
2991 built when the host and target are the same system. Child process
2992 handling and core file support are two common `native' examples.
2994 GDB's use of /proc for controlling Unix child processes is now cleaner.
2995 It has been split out into a single module under the `target_ops' vector,
2996 plus two native-dependent functions for each system that uses /proc.
2998 * New hosts supported
3000 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3001 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3002 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3004 * New targets supported
3006 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3007 68030 and CPU32 m68030-*-*, m68332-*-*
3009 * New native hosts supported
3011 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3012 (386bsd is not well tested yet)
3013 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3015 * New file formats supported
3017 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3018 supports reading of `a.out.adobe' object files, which are an a.out
3019 format extended with minimal information about multiple sections.
3023 `show copying' is the same as the old `info copying'.
3024 `show warranty' is the same as `info warrantee'.
3025 These were renamed for consistency. The old commands continue to work.
3027 `info handle' is a new alias for `info signals'.
3029 You can now define pre-command hooks, which attach arbitrary command
3030 scripts to any command. The commands in the hook will be executed
3031 prior to the user's command. You can also create a hook which will be
3032 executed whenever the program stops. See gdb.texinfo.
3036 We now deal with Cfront style name mangling, and can even extract type
3037 info from mangled symbols. GDB can automatically figure out which
3038 symbol mangling style your C++ compiler uses.
3040 Calling of methods and virtual functions has been improved as well.
3044 The crash that occured when debugging Sun Ansi-C compiled binaries is
3045 fixed. This was due to mishandling of the extra N_SO stabs output
3048 We also finally got Ultrix 4.2 running in house, and fixed core file
3049 support, with help from a dozen people on the net.
3051 John M. Farrell discovered that the reason that single-stepping was so
3052 slow on all of the Mips based platforms (primarily SGI and DEC) was
3053 that we were trying to demangle and lookup a symbol used for internal
3054 purposes on every instruction that was being stepped through. Changing
3055 the name of that symbol so that it couldn't be mistaken for a C++
3056 mangled symbol sped things up a great deal.
3058 Rich Pixley sped up symbol lookups in general by getting much smarter
3059 about when C++ symbol mangling is necessary. This should make symbol
3060 completion (TAB on the command line) much faster. It's not as fast as
3061 we'd like, but it's significantly faster than gdb-4.6.
3065 A new user controllable variable 'call_scratch_address' can
3066 specify the location of a scratch area to be used when GDB
3067 calls a function in the target. This is necessary because the
3068 usual method of putting the scratch area on the stack does not work
3069 in systems that have separate instruction and data spaces.
3071 We integrated changes to support the 29k UDI (Universal Debugger
3072 Interface), but discovered at the last minute that we didn't have all
3073 of the appropriate copyright paperwork. We are working with AMD to
3074 resolve this, and hope to have it available soon.
3078 We have sped up the remote serial line protocol, especially for targets
3079 with lots of registers. It now supports a new `expedited status' ('T')
3080 message which can be used in place of the existing 'S' status message.
3081 This allows the remote stub to send only the registers that GDB
3082 needs to make a quick decision about single-stepping or conditional
3083 breakpoints, eliminating the need to fetch the entire register set for
3084 each instruction being stepped through.
3086 The GDB remote serial protocol now implements a write-through cache for
3087 registers, only re-reading the registers if the target has run.
3089 There is also a new remote serial stub for SPARC processors. You can
3090 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3091 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3092 processor with a serial port.
3096 Configure.in files have become much easier to read and modify. A new
3097 `table driven' format makes it more obvious what configurations are
3098 supported, and what files each one uses.
3102 There is a new opcodes library which will eventually contain all of the
3103 disassembly routines and opcode tables. At present, it only contains
3104 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3105 disassembler (binutils/objdump) to share these routines.
3107 The libiberty library is now copylefted under the GNU Library General
3108 Public License. This allows more liberal use, and was done so libg++
3109 can use it. This makes no difference to GDB, since the Library License
3110 grants all the rights from the General Public License.
3114 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3115 reference to the stabs symbol info used by the debugger. It is (as far
3116 as we know) the only published document on this fascinating topic. We
3117 encourage you to read it, compare it to the stabs information on your
3118 system, and send improvements on the document in general (to
3119 bug-gdb@prep.ai.mit.edu).
3121 And, of course, many bugs have been fixed.
3124 *** Changes in GDB-4.6:
3126 * Better support for C++ function names
3128 GDB now accepts as input the "demangled form" of C++ overloaded function
3129 names and member function names, and can do command completion on such names
3130 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3131 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3132 Make use of command completion, it is your friend.
3134 GDB also now accepts a variety of C++ mangled symbol formats. They are
3135 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3136 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3137 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3138 for the list of formats.
3140 * G++ symbol mangling problem
3142 Recent versions of gcc have a bug in how they emit debugging information for
3143 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3144 directory) can be applied to gcc to fix the problem. Alternatively, if you
3145 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3146 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3147 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3150 * New 'maintenance' command
3152 All of the commands related to hacking GDB internals have been moved out of
3153 the main command set, and now live behind the 'maintenance' command. This
3154 can also be abbreviated as 'mt'. The following changes were made:
3156 dump-me -> maintenance dump-me
3157 info all-breakpoints -> maintenance info breakpoints
3158 printmsyms -> maintenance print msyms
3159 printobjfiles -> maintenance print objfiles
3160 printpsyms -> maintenance print psymbols
3161 printsyms -> maintenance print symbols
3163 The following commands are new:
3165 maintenance demangle Call internal GDB demangler routine to
3166 demangle a C++ link name and prints the result.
3167 maintenance print type Print a type chain for a given symbol
3169 * Change to .gdbinit file processing
3171 We now read the $HOME/.gdbinit file before processing the argv arguments
3172 (e.g. reading symbol files or core files). This allows global parameters to
3173 be set, which will apply during the symbol reading. The ./.gdbinit is still
3174 read after argv processing.
3176 * New hosts supported
3178 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3180 GNU/Linux support i386-unknown-linux or linux
3182 We are also including code to support the HP/PA running BSD and HPUX. This
3183 is almost guaranteed not to work, as we didn't have time to test or build it
3184 for this release. We are including it so that the more adventurous (or
3185 masochistic) of you can play with it. We also had major problems with the
3186 fact that the compiler that we got from HP doesn't support the -g option.
3189 * New targets supported
3191 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3193 * More smarts about finding #include files
3195 GDB now remembers the compilation directory for all include files, and for
3196 all files from which C is generated (like yacc and lex sources). This
3197 greatly improves GDB's ability to find yacc/lex sources, and include files,
3198 especially if you are debugging your program from a directory different from
3199 the one that contains your sources.
3201 We also fixed a bug which caused difficulty with listing and setting
3202 breakpoints in include files which contain C code. (In the past, you had to
3203 try twice in order to list an include file that you hadn't looked at before.)
3205 * Interesting infernals change
3207 GDB now deals with arbitrary numbers of sections, where the symbols for each
3208 section must be relocated relative to that section's landing place in the
3209 target's address space. This work was needed to support ELF with embedded
3210 stabs used by Solaris-2.0.
3212 * Bug fixes (of course!)
3214 There have been loads of fixes for the following things:
3215 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3216 i960, stabs, DOS(GO32), procfs, etc...
3218 See the ChangeLog for details.
3220 *** Changes in GDB-4.5:
3222 * New machines supported (host and target)
3224 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3226 SGI Irix-4.x mips-sgi-irix4 or iris4
3228 * New malloc package
3230 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3231 Mmalloc is capable of handling mutiple heaps of memory. It is also
3232 capable of saving a heap to a file, and then mapping it back in later.
3233 This can be used to greatly speedup the startup of GDB by using a
3234 pre-parsed symbol table which lives in a mmalloc managed heap. For
3235 more details, please read mmalloc/mmalloc.texi.
3239 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3240 'help info proc' for details.
3242 * MIPS ecoff symbol table format
3244 The code that reads MIPS symbol table format is now supported on all hosts.
3245 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3248 * File name changes for MS-DOS
3250 Many files in the config directories have been renamed to make it easier to
3251 support GDB on MS-DOSe systems (which have very restrictive file name
3252 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3253 environment) is close to working but has some remaining problems. Note
3254 that debugging of DOS programs is not supported, due to limitations
3255 in the ``operating system'', but it can be used to host cross-debugging.
3257 * Cross byte order fixes
3259 Many fixes have been made to support cross debugging of Sparc and MIPS
3260 targets from hosts whose byte order differs.
3262 * New -mapped and -readnow options
3264 If memory-mapped files are available on your system through the 'mmap'
3265 system call, you can use the -mapped option on the `file' or
3266 `symbol-file' commands to cause GDB to write the symbols from your
3267 program into a reusable file. If the program you are debugging is
3268 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3269 Future GDB debugging sessions will notice the presence of this file,
3270 and will quickly map in symbol information from it, rather than reading
3271 the symbol table from the executable program. Using the '-mapped'
3272 option in a GDB `file' or `symbol-file' command has the same effect as
3273 starting GDB with the '-mapped' command-line option.
3275 You can cause GDB to read the entire symbol table immediately by using
3276 the '-readnow' option with any of the commands that load symbol table
3277 information (or on the GDB command line). This makes the command
3278 slower, but makes future operations faster.
3280 The -mapped and -readnow options are typically combined in order to
3281 build a `fred.syms' file that contains complete symbol information.
3282 A simple GDB invocation to do nothing but build a `.syms' file for future
3285 gdb -batch -nx -mapped -readnow programname
3287 The `.syms' file is specific to the host machine on which GDB is run.
3288 It holds an exact image of GDB's internal symbol table. It cannot be
3289 shared across multiple host platforms.
3291 * longjmp() handling
3293 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3294 siglongjmp() without losing control. This feature has not yet been ported to
3295 all systems. It currently works on many 386 platforms, all MIPS-based
3296 platforms (SGI, DECstation, etc), and Sun3/4.
3300 Preliminary work has been put in to support the new Solaris OS from Sun. At
3301 this time, it can control and debug processes, but it is not capable of
3306 As always, many many bug fixes. The major areas were with g++, and mipsread.
3307 People using the MIPS-based platforms should experience fewer mysterious
3308 crashes and trashed symbol tables.
3310 *** Changes in GDB-4.4:
3312 * New machines supported (host and target)
3314 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3316 BSD Reno on Vax vax-dec-bsd
3317 Ultrix on Vax vax-dec-ultrix
3319 * New machines supported (target)
3321 AMD 29000 embedded, using EBMON a29k-none-none
3325 GDB continues to improve its handling of C++. `References' work better.
3326 The demangler has also been improved, and now deals with symbols mangled as
3327 per the Annotated C++ Reference Guide.
3329 GDB also now handles `stabs' symbol information embedded in MIPS
3330 `ecoff' symbol tables. Since the ecoff format was not easily
3331 extensible to handle new languages such as C++, this appeared to be a
3332 good way to put C++ debugging info into MIPS binaries. This option
3333 will be supported in the GNU C compiler, version 2, when it is
3336 * New features for SVR4
3338 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3339 shared libraries. Debugging dynamically linked programs should present
3340 only minor differences from debugging statically linked programs.
3342 The `info proc' command will print out information about any process
3343 on an SVR4 system (including the one you are debugging). At the moment,
3344 it prints the address mappings of the process.
3346 If you bring up GDB on another SVR4 system, please send mail to
3347 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3349 * Better dynamic linking support in SunOS
3351 Reading symbols from shared libraries which contain debugging symbols
3352 now works properly. However, there remain issues such as automatic
3353 skipping of `transfer vector' code during function calls, which
3354 make it harder to debug code in a shared library, than to debug the
3355 same code linked statically.
3359 GDB is now using the latest `getopt' routines from the FSF. This
3360 version accepts the -- prefix for options with long names. GDB will
3361 continue to accept the old forms (-option and +option) as well.
3362 Various single letter abbreviations for options have been explicity
3363 added to the option table so that they won't get overshadowed in the
3364 future by other options that begin with the same letter.
3368 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3369 Many assorted bugs have been handled. Many more remain to be handled.
3370 See the various ChangeLog files (primarily in gdb and bfd) for details.
3373 *** Changes in GDB-4.3:
3375 * New machines supported (host and target)
3377 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3378 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3379 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3381 * Almost SCO Unix support
3383 We had hoped to support:
3384 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3385 (except for core file support), but we discovered very late in the release
3386 that it has problems with process groups that render gdb unusable. Sorry
3387 about that. I encourage people to fix it and post the fixes.
3389 * Preliminary ELF and DWARF support
3391 GDB can read ELF object files on System V Release 4, and can handle
3392 debugging records for C, in DWARF format, in ELF files. This support
3393 is preliminary. If you bring up GDB on another SVR4 system, please
3394 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3399 GDB now uses the latest `readline' library. One user-visible change
3400 is that two tabs will list possible command completions, which previously
3401 required typing M-? (meta-question mark, or ESC ?).
3405 The `stepi' bug that many of you noticed has been squashed.
3406 Many bugs in C++ have been handled. Many more remain to be handled.
3407 See the various ChangeLog files (primarily in gdb and bfd) for details.
3409 * State of the MIPS world (in case you wondered):
3411 GDB can understand the symbol tables emitted by the compilers
3412 supplied by most vendors of MIPS-based machines, including DEC. These
3413 symbol tables are in a format that essentially nobody else uses.
3415 Some versions of gcc come with an assembler post-processor called
3416 mips-tfile. This program is required if you want to do source-level
3417 debugging of gcc-compiled programs. I believe FSF does not ship
3418 mips-tfile with gcc version 1, but it will eventually come with gcc
3421 Debugging of g++ output remains a problem. g++ version 1.xx does not
3422 really support it at all. (If you're lucky, you should be able to get
3423 line numbers and stack traces to work, but no parameters or local
3424 variables.) With some work it should be possible to improve the
3427 When gcc version 2 is released, you will have somewhat better luck.
3428 However, even then you will get confusing results for inheritance and
3431 We will eventually provide full debugging of g++ output on
3432 DECstations. This will probably involve some kind of stabs-in-ecoff
3433 encapulation, but the details have not been worked out yet.
3436 *** Changes in GDB-4.2:
3438 * Improved configuration
3440 Only one copy of `configure' exists now, and it is not self-modifying.
3441 Porting BFD is simpler.
3445 The `step' and `next' commands now only stop at the first instruction
3446 of a source line. This prevents the multiple stops that used to occur
3447 in switch statements, for-loops, etc. `Step' continues to stop if a
3448 function that has debugging information is called within the line.
3452 Lots of small bugs fixed. More remain.
3454 * New host supported (not target)
3456 Intel 386 PC clone running Mach i386-none-mach
3459 *** Changes in GDB-4.1:
3461 * Multiple source language support
3463 GDB now has internal scaffolding to handle several source languages.
3464 It determines the type of each source file from its filename extension,
3465 and will switch expression parsing and number formatting to match the
3466 language of the function in the currently selected stack frame.
3467 You can also specifically set the language to be used, with
3468 `set language c' or `set language modula-2'.
3472 GDB now has preliminary support for the GNU Modula-2 compiler,
3473 currently under development at the State University of New York at
3474 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3475 continue through the fall of 1991 and into 1992.
3477 Other Modula-2 compilers are currently not supported, and attempting to
3478 debug programs compiled with them will likely result in an error as the
3479 symbol table is read. Feel free to work on it, though!
3481 There are hooks in GDB for strict type checking and range checking,
3482 in the `Modula-2 philosophy', but they do not currently work.
3486 GDB can now write to executable and core files (e.g. patch
3487 a variable's value). You must turn this switch on, specify
3488 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3489 by assigning a new value to a variable. Modifications take
3492 * Automatic SunOS shared library reading
3494 When you run your program, GDB automatically determines where its
3495 shared libraries (if any) have been loaded, and reads their symbols.
3496 The `share' command is no longer needed. This also works when
3497 examining core files.
3501 You can specify the number of lines that the `list' command shows.
3504 * New machines supported (host and target)
3506 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3507 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3508 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3510 * New hosts supported (not targets)
3512 IBM RT/PC: romp-ibm-aix or rtpc
3514 * New targets supported (not hosts)
3516 AMD 29000 embedded with COFF a29k-none-coff
3517 AMD 29000 embedded with a.out a29k-none-aout
3518 Ultracomputer remote kernel debug a29k-nyu-kern
3520 * New remote interfaces
3526 *** Changes in GDB-4.0:
3530 Wide output is wrapped at good places to make the output more readable.
3532 Gdb now supports cross-debugging from a host machine of one type to a
3533 target machine of another type. Communication with the target system
3534 is over serial lines. The ``target'' command handles connecting to the
3535 remote system; the ``load'' command will download a program into the
3536 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3537 also supports debugging of realtime processes running under VxWorks,
3538 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3539 stub on the target system.
3541 New CPUs supported include the AMD 29000 and Intel 960.
3543 GDB now reads object files and symbol tables via a ``binary file''
3544 library, which allows a single copy of GDB to debug programs of multiple
3545 object file types such as a.out and coff.
3547 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3548 refcard.dvi and refcard.ps are available to format it).
3551 * Control-Variable user interface simplified
3553 All variables that control the operation of the debugger can be set
3554 by the ``set'' command, and displayed by the ``show'' command.
3556 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3557 ``Show prompt'' produces the response:
3558 Gdb's prompt is new-gdb=>.
3560 What follows are the NEW set commands. The command ``help set'' will
3561 print a complete list of old and new set commands. ``help set FOO''
3562 will give a longer description of the variable FOO. ``show'' will show
3563 all of the variable descriptions and their current settings.
3565 confirm on/off: Enables warning questions for operations that are
3566 hard to recover from, e.g. rerunning the program while
3567 it is already running. Default is ON.
3569 editing on/off: Enables EMACS style command line editing
3570 of input. Previous lines can be recalled with
3571 control-P, the current line can be edited with control-B,
3572 you can search for commands with control-R, etc.
3575 history filename NAME: NAME is where the gdb command history
3576 will be stored. The default is .gdb_history,
3577 or the value of the environment variable
3580 history size N: The size, in commands, of the command history. The
3581 default is 256, or the value of the environment variable
3584 history save on/off: If this value is set to ON, the history file will
3585 be saved after exiting gdb. If set to OFF, the
3586 file will not be saved. The default is OFF.
3588 history expansion on/off: If this value is set to ON, then csh-like
3589 history expansion will be performed on
3590 command line input. The default is OFF.
3592 radix N: Sets the default radix for input and output. It can be set
3593 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3594 in the current radix, so "set radix 10" is always a no-op.
3596 height N: This integer value is the number of lines on a page. Default
3597 is 24, the current `stty rows'' setting, or the ``li#''
3598 setting from the termcap entry matching the environment
3601 width N: This integer value is the number of characters on a line.
3602 Default is 80, the current `stty cols'' setting, or the ``co#''
3603 setting from the termcap entry matching the environment
3606 Note: ``set screensize'' is obsolete. Use ``set height'' and
3607 ``set width'' instead.
3609 print address on/off: Print memory addresses in various command displays,
3610 such as stack traces and structure values. Gdb looks
3611 more ``symbolic'' if you turn this off; it looks more
3612 ``machine level'' with it on. Default is ON.
3614 print array on/off: Prettyprint arrays. New convenient format! Default
3617 print demangle on/off: Print C++ symbols in "source" form if on,
3620 print asm-demangle on/off: Same, for assembler level printouts
3623 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3626 * Support for Epoch Environment.
3628 The epoch environment is a version of Emacs v18 with windowing. One
3629 new command, ``inspect'', is identical to ``print'', except that if you
3630 are running in the epoch environment, the value is printed in its own
3634 * Support for Shared Libraries
3636 GDB can now debug programs and core files that use SunOS shared libraries.
3637 Symbols from a shared library cannot be referenced
3638 before the shared library has been linked with the program (this
3639 happens after you type ``run'' and before the function main() is entered).
3640 At any time after this linking (including when examining core files
3641 from dynamically linked programs), gdb reads the symbols from each
3642 shared library when you type the ``sharedlibrary'' command.
3643 It can be abbreviated ``share''.
3645 sharedlibrary REGEXP: Load shared object library symbols for files
3646 matching a unix regular expression. No argument
3647 indicates to load symbols for all shared libraries.
3649 info sharedlibrary: Status of loaded shared libraries.
3654 A watchpoint stops execution of a program whenever the value of an
3655 expression changes. Checking for this slows down execution
3656 tremendously whenever you are in the scope of the expression, but is
3657 quite useful for catching tough ``bit-spreader'' or pointer misuse
3658 problems. Some machines such as the 386 have hardware for doing this
3659 more quickly, and future versions of gdb will use this hardware.
3661 watch EXP: Set a watchpoint (breakpoint) for an expression.
3663 info watchpoints: Information about your watchpoints.
3665 delete N: Deletes watchpoint number N (same as breakpoints).
3666 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3667 enable N: Re-enables watchpoint number N (same as breakpoints).
3670 * C++ multiple inheritance
3672 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3675 * C++ exception handling
3677 Gdb now supports limited C++ exception handling. Besides the existing
3678 ability to breakpoint on an exception handler, gdb can breakpoint on
3679 the raising of an exception (before the stack is peeled back to the
3682 catch FOO: If there is a FOO exception handler in the dynamic scope,
3683 set a breakpoint to catch exceptions which may be raised there.
3684 Multiple exceptions (``catch foo bar baz'') may be caught.
3686 info catch: Lists all exceptions which may be caught in the
3687 current stack frame.
3690 * Minor command changes
3692 The command ``call func (arg, arg, ...)'' now acts like the print
3693 command, except it does not print or save a value if the function's result
3694 is void. This is similar to dbx usage.
3696 The ``up'' and ``down'' commands now always print the frame they end up
3697 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3698 frames without printing.
3700 * New directory command
3702 'dir' now adds directories to the FRONT of the source search path.
3703 The path starts off empty. Source files that contain debug information
3704 about the directory in which they were compiled can be found even
3705 with an empty path; Sun CC and GCC include this information. If GDB can't
3706 find your source file in the current directory, type "dir .".
3708 * Configuring GDB for compilation
3710 For normal use, type ``./configure host''. See README or gdb.texinfo
3713 GDB now handles cross debugging. If you are remotely debugging between
3714 two different machines, type ``./configure host -target=targ''.
3715 Host is the machine where GDB will run; targ is the machine
3716 where the program that you are debugging will run.