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 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
52 now complete on file names.
54 * When completing in expressions, gdb will attempt to limit
55 completions to allowable structure or union fields, where appropriate.
56 For instance, consider:
58 # struct example { int f1; double f2; };
59 # struct example variable;
62 If the user types TAB at the end of this command line, the available
63 completions will be "f1" and "f2".
65 * Inlined functions are now supported. They show up in backtraces, and
66 the "step", "next", and "finish" commands handle them automatically.
68 * GDB now supports the token-splicing (##) and stringification (#)
69 operators when expanding macros. It also supports variable-arity
72 * GDB now supports inspecting extra signal information, exported by
73 the new $_siginfo convenience variable. The feature is currently
74 implemented on linux ARM, i386 and amd64.
76 * GDB can now display the VFP floating point registers and NEON vector
77 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
78 can provide these registers (requires Linux 2.6.30 or later). Remote
79 and simulator targets may also provide them.
84 Search memory for a sequence of bytes.
87 Turn off `+'/`-' protocol acknowledgments to permit more efficient
88 operation over reliable transport links. Use of this packet is
89 controlled by the `set remote noack-packet' command.
92 Kill the process with the specified process ID. Use this in preference
93 to `k' when multiprocess protocol extensions are supported.
96 Obtains additional operating system information
100 Read or write additional signal information.
102 * Removed remote protocol undocumented extension
104 An undocumented extension to the remote protocol's `S' stop reply
105 packet that permited the stub to pass a process id was removed.
106 Remote servers should use the `T' stop reply packet instead.
108 * The "disassemble" command now supports an optional /m modifier to print mixed
111 * GDB now supports multiple function calling conventions according to the
112 DWARF-2 DW_AT_calling_convention function attribute.
114 * The SH target utilizes the aforementioned change to distinguish between gcc
115 and Renesas calling convention. It also adds the new CLI commands
116 `set/show sh calling-convention'.
118 * GDB can now read compressed debug sections, as produced by GNU gold
119 with the --compress-debug-sections=zlib flag.
121 * 64-bit core files are now supported on AIX.
123 * Thread switching is now supported on Tru64.
125 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
126 which will be allocated using malloc later in program execution.
128 * The qXfer:libraries:read remote procotol packet now allows passing a
129 list of section offsets.
131 * On GNU/Linux, GDB can now attach to stopped processes. Several race
132 conditions handling signals delivered during attach or thread creation
133 have also been fixed.
135 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
136 From the user's standpoint, all unqualified instances of True and False
137 are treated as the standard definitions, regardless of context.
139 * GDB now parses C++ symbol and type names more flexibly. For
142 template<typename T> class C { };
145 GDB will now correctly handle all of:
147 ptype C<char const *>
149 ptype C<const char *>
152 * New features in the GDB remote stub, gdbserver
154 - The "--wrapper" command-line argument tells gdbserver to use a
155 wrapper program to launch programs for debugging.
157 - On PowerPC and S/390 targets, it is now possible to use a single
158 gdbserver executable to debug both 32-bit and 64-bit programs.
159 (This requires gdbserver itself to be built as a 64-bit executable.)
161 - gdbserver uses the new noack protocol mode for TCP connections to
162 reduce communications latency, if also supported and enabled in GDB.
164 - Support for the sparc64-linux-gnu target is now included in
167 - The amd64-linux build of gdbserver now supports debugging both
168 32-bit and 64-bit programs.
170 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
171 now support hardware watchpoints, and will use them automatically
176 GDB now has support for scripting using Python. Whether this is
177 available is determined at configure time.
179 New GDB commands can now be written in Python.
181 * Ada tasking support
183 Ada tasks can now be inspected in GDB. The following commands have
187 Print the list of Ada tasks.
189 Print detailed information about task number N.
191 Print the task number of the current task.
193 Switch the context of debugging to task number N.
195 * Support for user-defined prefixed commands. The "define" command can
196 add new commands to existing prefixes, e.g. "target".
198 * Multi-inferior, multi-process debugging.
200 GDB now has generalized support for multi-inferior debugging. See
201 "Debugging Multiple Inferiors" in the manual for more information.
202 Although availability still depends on target support, the command
203 set is more uniform now. The GNU/Linux specific multi-forks support
204 has been migrated to this new framework. This implied some user
205 visible changes; see "New commands" and also "Removed commands"
208 * Target descriptions can now describe the target OS ABI. See the
209 "Target Description Format" section in the user manual for more
212 * Target descriptions can now describe "compatible" architectures
213 to indicate that the target can execute applications for a different
214 architecture in addition to those for the main target architecture.
215 See the "Target Description Format" section in the user manual for
218 * Multi-architecture debugging.
220 GDB now includes general supports for debugging applications on
221 hybrid systems that use more than one single processor architecture
222 at the same time. Each such hybrid architecture still requires
223 specific support to be added. The only hybrid architecture supported
224 in this version of GDB is the Cell Broadband Engine.
226 * GDB now supports integrated debugging of Cell/B.E. applications that
227 use both the PPU and SPU architectures. To enable support for hybrid
228 Cell/B.E. debugging, you need to configure GDB to support both the
229 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
230 --enable-targets configure option.
232 * New commands (for set/show, see "New options" below)
234 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
236 Search memory for a sequence of bytes.
238 maint set python print-stack
239 maint show python print-stack
240 Show a stack trace when an error is encountered in a Python script.
243 Invoke CODE by passing it to the Python interpreter.
248 These allow macros to be defined, undefined, and listed
252 Show operating system information about processes.
255 List the inferiors currently under GDB's control.
258 Switch focus to inferior number NUM.
261 Detach from inferior number NUM.
264 Kill inferior number NUM.
269 show spu stop-on-load
270 Control whether to stop for new SPE threads during Cell/B.E. debugging.
272 set spu auto-flush-cache
273 show spu auto-flush-cache
274 Control whether to automatically flush the software-managed cache
275 during Cell/B.E. debugging.
277 set sh calling-convention
278 show sh calling-convention
279 Control the calling convention used when calling SH target functions.
281 set print symbol-loading
282 show print symbol-loading
283 Control printing of symbol loading messages.
287 Control display of timestamps with GDB debugging output.
289 set disassemble-next-line
290 show disassemble-next-line
291 Control display of disassembled source lines or instructions when
294 set remote noack-packet
295 show remote noack-packet
296 Set/show the use of remote protocol QStartNoAckMode packet. See above
297 under "New remote packets."
299 set remote query-attached-packet
300 show remote query-attached-packet
301 Control use of remote protocol `qAttached' (query-attached) packet.
303 set remote read-siginfo-object
304 show remote read-siginfo-object
305 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
308 set remote write-siginfo-object
309 show remote write-siginfo-object
310 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
313 set displaced-stepping
314 show displaced-stepping
315 Control displaced stepping mode. Displaced stepping is a way to
316 single-step over breakpoints without removing them from the debuggee.
317 Also known as "out-of-line single-stepping".
321 Control display of debugging info for displaced stepping.
323 maint set internal-error
324 maint show internal-error
325 Control what GDB does when an internal error is detected.
327 maint set internal-warning
328 maint show internal-warning
329 Control what GDB does when an internal warning is detected.
334 Use a wrapper program to launch programs for debugging.
336 set multiple-symbols (all|ask|cancel)
337 show multiple-symbols
338 The value of this variable can be changed to adjust the debugger behavior
339 when an expression or a breakpoint location contains an ambiguous symbol
340 name (an overloaded function name, for instance).
342 set breakpoint always-inserted
343 show breakpoint always-inserted
344 Keep breakpoints always inserted in the target, as opposed to inserting
345 them when resuming the target, and removing them when the target stops.
346 This option can improve debugger performance on slow remote targets.
348 set arm fallback-mode (arm|thumb|auto)
349 show arm fallback-mode
350 set arm force-mode (arm|thumb|auto)
352 These commands control how ARM GDB determines whether instructions
353 are ARM or Thumb. The default for both settings is auto, which uses
354 the current CPSR value for instructions without symbols; previous
355 versions of GDB behaved as if "set arm fallback-mode arm".
357 set disable-randomization
358 show disable-randomization
359 Standalone programs run with the virtual address space randomization enabled
360 by default on some platforms. This option keeps the addresses stable across
361 multiple debugging sessions.
365 Control whether other threads are stopped or not when some thread hits
370 Requests that asynchronous execution is enabled in the target, if available.
371 In this case, it's possible to resume target in the background, and interact
372 with GDB while the target is running. "show target-async" displays the
373 current state of asynchronous execution of the target.
375 set target-wide-charset
376 show target-wide-charset
377 The target-wide-charset is the name of the character set that GDB
378 uses when printing characters whose type is wchar_t.
380 set tcp auto-retry (on|off)
382 set tcp connect-timeout
383 show tcp connect-timeout
384 These commands allow GDB to retry failed TCP connections to a remote stub
385 with a specified timeout period; this is useful if the stub is launched
386 in parallel with GDB but may not be ready to accept connections immediately.
388 set libthread-db-search-path
389 show libthread-db-search-path
390 Control list of directories which GDB will search for appropriate
393 set schedule-multiple (on|off)
394 show schedule-multiple
395 Allow GDB to resume all threads of all processes or only threads of
401 For program forks, this is replaced by the new more generic `info
402 inferiors' command. To list checkpoints, you can still use the
403 `info checkpoints' command, which was an alias for the `info forks'
407 Replaced by the new `inferior' command. To switch between
408 checkpoints, you can still use the `restart' command, which was an
409 alias for the `fork' command.
412 This is removed, since some targets don't have a notion of
413 processes. To switch between processes, you can still use the
414 `inferior' command using GDB's own inferior number.
417 For program forks, this is replaced by the new more generic `kill
418 inferior' command. To delete a checkpoint, you can still use the
419 `delete checkpoint' command, which was an alias for the `delete
423 For program forks, this is replaced by the new more generic `detach
424 inferior' command. To detach a checkpoint, you can still use the
425 `detach checkpoint' command, which was an alias for the `detach
428 * New native configurations
430 x86/x86_64 Darwin i[34567]86-*-darwin*
432 x86_64 MinGW x86_64-*-mingw*
436 Lattice Mico32 lm32-*
437 x86 DICOS i[34567]86-*-dicos*
438 x86_64 DICOS x86_64-*-dicos*
441 * The GDB remote stub, gdbserver, now supports x86 Windows CE
442 (mingw32ce) debugging.
448 These commands were actually not implemented on any target.
450 *** Changes in GDB 6.8
452 * New native configurations
454 NetBSD/hppa hppa*-*netbsd*
455 Xtensa GNU/Linux xtensa*-*-linux*
459 NetBSD/hppa hppa*-*-netbsd*
460 Xtensa GNU/Lunux xtensa*-*-linux*
462 * Change in command line behavior -- corefiles vs. process ids.
464 When the '-p NUMBER' or '--pid NUMBER' options are used, and
465 attaching to process NUMBER fails, GDB no longer attempts to open a
466 core file named NUMBER. Attaching to a program using the -c option
467 is no longer supported. Instead, use the '-p' or '--pid' options.
469 * GDB can now be built as a native debugger for debugging Windows x86
470 (mingw32) Portable Executable (PE) programs.
472 * Pending breakpoints no longer change their number when their address
475 * GDB now supports breakpoints with multiple locations,
476 including breakpoints on C++ constructors, inside C++ templates,
477 and in inlined functions.
479 * GDB's ability to debug optimized code has been improved. GDB more
480 accurately identifies function bodies and lexical blocks that occupy
481 more than one contiguous range of addresses.
483 * Target descriptions can now describe registers for PowerPC.
485 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
486 registers on PowerPC targets.
488 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
489 targets even when the libthread_db library is not available.
491 * The GDB remote stub, gdbserver, now supports the new file transfer
492 commands (remote put, remote get, and remote delete).
494 * The GDB remote stub, gdbserver, now supports run and attach in
495 extended-remote mode.
497 * hppa*64*-*-hpux11* target broken
498 The debugger is unable to start a program and fails with the following
499 error: "Error trying to get information about dynamic linker".
500 The gdb-6.7 release is also affected.
502 * GDB now supports the --enable-targets= configure option to allow
503 building a single GDB executable that supports multiple remote
504 target architectures.
506 * GDB now supports debugging C and C++ programs which use the
507 Decimal Floating Point extension. In addition, the PowerPC target
508 now has a set of pseudo-registers to inspect decimal float values
509 stored in two consecutive float registers.
511 * The -break-insert MI command can optionally create pending
514 * Improved support for debugging Ada
515 Many improvements to the Ada language support have been made. These
517 - Better support for Ada2005 interface types
518 - Improved handling of arrays and slices in general
519 - Better support for Taft-amendment types
520 - The '{type} ADDRESS' expression is now allowed on the left hand-side
522 - Improved command completion in Ada
525 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
530 set print frame-arguments (all|scalars|none)
531 show print frame-arguments
532 The value of this variable can be changed to control which argument
533 values should be printed by the debugger when displaying a frame.
538 Transfer files to and from a remote target, and delete remote files.
545 Transfer files to and from a remote target, and delete remote files.
554 Open, close, read, write, and delete files on the remote system.
557 Attach to an existing process on the remote system, in extended-remote
561 Run a new process on the remote system, in extended-remote mode.
563 *** Changes in GDB 6.7
565 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
566 bfd, libiberty and opcodes, as revealed by static analysis donated by
567 Coverity, Inc. (http://scan.coverity.com).
569 * When looking up multiply-defined global symbols, GDB will now prefer the
570 symbol definition in the current shared library if it was built using the
571 -Bsymbolic linker option.
573 * When the Text User Interface (TUI) is not configured, GDB will now
574 recognize the -tui command-line option and print a message that the TUI
577 * The GDB remote stub, gdbserver, now has lower overhead for high
578 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
580 * GDB for MIPS targets now autodetects whether a remote target provides
581 32-bit or 64-bit register values.
583 * Support for C++ member pointers has been improved.
585 * GDB now understands XML target descriptions, which specify the
586 target's overall architecture. GDB can read a description from
587 a local file or over the remote serial protocol.
589 * Vectors of single-byte data use a new integer type which is not
590 automatically displayed as character or string data.
592 * The /s format now works with the print command. It displays
593 arrays of single-byte integers and pointers to single-byte integers
596 * Target descriptions can now describe target-specific registers,
597 for architectures which have implemented the support (currently
598 only ARM, M68K, and MIPS).
600 * GDB and the GDB remote stub, gdbserver, now support the XScale
603 * The GDB remote stub, gdbserver, has been updated to support
604 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
605 has been rewritten to use the standard GDB remote protocol.
607 * GDB can now step into C++ functions which are called through thunks.
609 * GDB for the Cell/B.E. SPU now supports overlay debugging.
611 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
612 layout. It also supports a TextSeg= and DataSeg= response when only
613 segment base addresses (rather than offsets) are available.
615 * The /i format now outputs any trailing branch delay slot instructions
616 immediately following the last instruction within the count specified.
618 * The GDB remote protocol "T" stop reply packet now supports a
619 "library" response. Combined with the new "qXfer:libraries:read"
620 packet, this response allows GDB to debug shared libraries on targets
621 where the operating system manages the list of loaded libraries (e.g.
622 Windows and SymbianOS).
624 * The GDB remote stub, gdbserver, now supports dynamic link libraries
625 (DLLs) on Windows and Windows CE targets.
627 * GDB now supports a faster verification that a .debug file matches its binary
628 according to its build-id signature, if the signature is present.
634 Enable or disable hardware flow control (RTS/CTS) on the serial port
635 when debugging using remote targets.
637 set mem inaccessible-by-default
638 show mem inaccessible-by-default
639 If the target supplies a memory map, for instance via the remote
640 protocol's "qXfer:memory-map:read" packet, setting this variable
641 prevents GDB from accessing memory outside the memory map. This
642 is useful for targets with memory mapped registers or which react
643 badly to accesses of unmapped address space.
645 set breakpoint auto-hw
646 show breakpoint auto-hw
647 If the target supplies a memory map, for instance via the remote
648 protocol's "qXfer:memory-map:read" packet, setting this variable
649 lets GDB use hardware breakpoints automatically for memory regions
650 where it can not use software breakpoints. This covers both the
651 "break" command and internal breakpoints used for other commands
652 including "next" and "finish".
655 catch exception unhandled
656 Stop the program execution when Ada exceptions are raised.
659 Stop the program execution when an Ada assertion failed.
663 Set an alternate system root for target files. This is a more
664 general version of "set solib-absolute-prefix", which is now
665 an alias to "set sysroot".
668 Provide extended SPU facility status information. This set of
669 commands is available only when debugging the Cell/B.E. SPU
672 * New native configurations
674 OpenBSD/sh sh*-*openbsd*
679 Use the specified local file as an XML target description, and do
680 not query the target for its built-in description.
684 OpenBSD/sh sh*-*-openbsd*
685 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
686 Toshiba Media Processor mep-elf
691 Ignore the specified signals; pass them directly to the debugged program
692 without stopping other threads or reporting them to GDB.
695 Read an XML target description from the target, which describes its
700 Read or write contents of an spufs file on the target system. These
701 packets are available only on the Cell/B.E. SPU architecture.
703 qXfer:libraries:read:
704 Report the loaded shared libraries. Combined with new "T" packet
705 response, this packet allows GDB to debug shared libraries on
706 targets where the operating system manages the list of loaded
707 libraries (e.g. Windows and SymbianOS).
711 Support for these obsolete configurations has been removed.
720 i[34567]86-*-netware*
721 i[34567]86-*-sco3.2v5*
722 i[34567]86-*-sco3.2v4*
724 i[34567]86-*-sysv4.2*
727 i[34567]86-*-unixware2*
728 i[34567]86-*-unixware*
737 * Other removed features
744 Various m68k-only ROM monitors.
751 Various Renesas ROM monitors and debugging interfaces for SH and
756 Support for a Macraigor serial interface to on-chip debugging.
757 GDB does not directly support the newer parallel or USB
762 A debug information format. The predecessor to DWARF 2 and
763 DWARF 3, which are still supported.
765 Support for the HP aCC compiler on HP-UX/PA-RISC
767 SOM-encapsulated symbolic debugging information, automatic
768 invocation of pxdb, and the aCC custom C++ ABI. This does not
769 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
770 with aCC can still be debugged on an assembly level.
774 A MIPS-specific format used to describe stack frame layout
775 in debugging information.
779 GDB could work with an older version of Guile to debug
780 the interpreter and Scheme programs running in it.
782 set mips stack-arg-size
783 set mips saved-gpreg-size
785 Use "set mips abi" to control parameter passing for MIPS.
787 *** Changes in GDB 6.6
792 Cell Broadband Engine SPU spu-elf
794 * GDB can now be configured as a cross-debugger targeting native Windows
795 (mingw32) or Cygwin. It can communicate with a remote debugging stub
796 running on a Windows system over TCP/IP to debug Windows programs.
798 * The GDB remote stub, gdbserver, has been updated to support Windows and
799 Cygwin debugging. Both single-threaded and multi-threaded programs are
802 * The "set trust-readonly-sections" command works again. This command was
803 broken in GDB 6.3, 6.4, and 6.5.
805 * The "load" command now supports writing to flash memory, if the remote
806 stub provides the required support.
808 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
809 longer requires symbolic debug information (e.g. DWARF-2).
814 unset substitute-path
816 Manage a list of substitution rules that GDB uses to rewrite the name
817 of the directories where the sources are located. This can be useful
818 for instance when the sources were moved to a different location
819 between compilation and debugging.
823 Print each CLI command as it is executed. Each command is prefixed with
824 a number of `+' symbols representing the nesting depth.
825 The source command now has a `-v' option to enable the same feature.
829 The ARM Demon monitor support (RDP protocol, "target rdp").
831 Kernel Object Display, an embedded debugging feature which only worked with
832 an obsolete version of Cisco IOS.
834 The 'set download-write-size' and 'show download-write-size' commands.
839 Tell a stub about GDB client features, and request remote target features.
840 The first feature implemented is PacketSize, which allows the target to
841 specify the size of packets it can handle - to minimize the number of
842 packets required and improve performance when connected to a remote
846 Fetch an OS auxilliary vector from the remote stub. This packet is a
847 more efficient replacement for qPart:auxv:read.
849 qXfer:memory-map:read:
850 Fetch a memory map from the remote stub, including information about
851 RAM, ROM, and flash memory devices.
856 Erase and program a flash memory device.
858 * Removed remote packets
861 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
862 used it, and only gdbserver implemented it.
864 *** Changes in GDB 6.5
868 Renesas M32C/M16C m32c-elf
870 Morpho Technologies ms1 ms1-elf
874 init-if-undefined Initialize a convenience variable, but
875 only if it doesn't already have a value.
877 The following commands are presently only implemented for native GNU/Linux:
879 checkpoint Save a snapshot of the program state.
881 restart <n> Return the program state to a
882 previously saved state.
884 info checkpoints List currently saved checkpoints.
886 delete-checkpoint <n> Delete a previously saved checkpoint.
888 set|show detach-on-fork Tell gdb whether to detach from a newly
889 forked process, or to keep debugging it.
891 info forks List forks of the user program that
892 are available to be debugged.
894 fork <n> Switch to debugging one of several
895 forks of the user program that are
896 available to be debugged.
898 delete-fork <n> Delete a fork from the list of forks
899 that are available to be debugged (and
900 kill the forked process).
902 detach-fork <n> Delete a fork from the list of forks
903 that are available to be debugged (and
904 allow the process to continue).
908 Morpho Technologies ms2 ms1-elf
910 * Improved Windows host support
912 GDB now builds as a cross debugger hosted on i686-mingw32, including
913 native console support, and remote communications using either
914 network sockets or serial ports.
916 * Improved Modula-2 language support
918 GDB can now print most types in the Modula-2 syntax. This includes:
919 basic types, set types, record types, enumerated types, range types,
920 pointer types and ARRAY types. Procedure var parameters are correctly
921 printed and hexadecimal addresses and character constants are also
922 written in the Modula-2 syntax. Best results can be obtained by using
923 GNU Modula-2 together with the -gdwarf-2 command line option.
927 The ARM rdi-share module.
929 The Netware NLM debug server.
931 *** Changes in GDB 6.4
933 * New native configurations
935 OpenBSD/arm arm*-*-openbsd*
936 OpenBSD/mips64 mips64-*-openbsd*
940 Morpho Technologies ms1 ms1-elf
942 * New command line options
944 --batch-silent As for --batch, but totally silent.
945 --return-child-result The debugger will exist with the same value
946 the child (debugged) program exited with.
947 --eval-command COMMAND, -ex COMMAND
948 Execute a single GDB CLI command. This may be
949 specified multiple times and in conjunction
950 with the --command (-x) option.
952 * Deprecated commands removed
954 The following commands, that were deprecated in 2000, have been
958 set|show arm disassembly-flavor set|show arm disassembler
959 othernames set arm disassembler
960 set|show remotedebug set|show debug remote
961 set|show archdebug set|show debug arch
962 set|show eventdebug set|show debug event
965 * New BSD user-level threads support
967 It is now possible to debug programs using the user-level threads
968 library on OpenBSD and FreeBSD. Currently supported (target)
971 FreeBSD/amd64 x86_64-*-freebsd*
972 FreeBSD/i386 i386-*-freebsd*
973 OpenBSD/i386 i386-*-openbsd*
975 Note that the new kernel threads libraries introduced in FreeBSD 5.x
976 are not yet supported.
978 * New support for Matsushita MN10300 w/sim added
979 (Work in progress). mn10300-elf.
981 * REMOVED configurations and files
983 VxWorks and the XDR protocol *-*-vxworks
984 Motorola MCORE mcore-*-*
985 National Semiconductor NS32000 ns32k-*-*
987 * New "set print array-indexes" command
989 After turning this setting "on", GDB prints the index of each element
990 when displaying arrays. The default is "off" to preserve the previous
993 * VAX floating point support
995 GDB now supports the not-quite-ieee VAX F and D floating point formats.
997 * User-defined command support
999 In addition to using $arg0..$arg9 for argument passing, it is now possible
1000 to use $argc to determine now many arguments have been passed. See the
1001 section on user-defined commands in the user manual for more information.
1003 *** Changes in GDB 6.3:
1005 * New command line option
1007 GDB now accepts -l followed by a number to set the timeout for remote
1010 * GDB works with GCC -feliminate-dwarf2-dups
1012 GDB now supports a more compact representation of DWARF-2 debug
1013 information using DW_FORM_ref_addr references. These are produced
1014 by GCC with the option -feliminate-dwarf2-dups and also by some
1015 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1016 to use -feliminate-dwarf2-dups.
1018 * Internationalization
1020 When supported by the host system, GDB will be built with
1021 internationalization (libintl). The task of marking up the sources is
1022 continued, we're looking forward to our first translation.
1026 Initial support for debugging programs compiled with the GNAT
1027 implementation of the Ada programming language has been integrated
1028 into GDB. In this release, support is limited to expression evaluation.
1030 * New native configurations
1032 GNU/Linux/m32r m32r-*-linux-gnu
1036 GDB's remote protocol now includes support for the 'p' packet. This
1037 packet is used to fetch individual registers from a remote inferior.
1039 * END-OF-LIFE registers[] compatibility module
1041 GDB's internal register infrastructure has been completely rewritten.
1042 The new infrastructure making possible the implementation of key new
1043 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1046 GDB 6.3 will be the last release to include the the registers[]
1047 compatibility module that allowed out-of-date configurations to
1048 continue to work. This change directly impacts the following
1058 powerpc bdm protocol
1060 Unless there is activity to revive these configurations, they will be
1061 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1063 * OBSOLETE configurations and files
1065 Configurations that have been declared obsolete in this release have
1066 been commented out. Unless there is activity to revive these
1067 configurations, the next release of GDB will have their sources
1068 permanently REMOVED.
1077 *** Changes in GDB 6.2.1:
1079 * MIPS `break main; run' gave an heuristic-fence-post warning
1081 When attempting to run even a simple program, a warning about
1082 heuristic-fence-post being hit would be reported. This problem has
1085 * MIPS IRIX 'long double' crashed GDB
1087 When examining a long double variable, GDB would get a segmentation
1088 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1089 IRIX long double values).
1093 A bug in the VAX stack code was causing problems with the "next"
1094 command. This problem has been fixed.
1096 *** Changes in GDB 6.2:
1098 * Fix for ``many threads''
1100 On GNU/Linux systems that use the NPTL threads library, a program
1101 rapidly creating and deleting threads would confuse GDB leading to the
1104 ptrace: No such process.
1105 thread_db_get_info: cannot get thread info: generic error
1107 This problem has been fixed.
1109 * "-async" and "-noasync" options removed.
1111 Support for the broken "-noasync" option has been removed (it caused
1114 * New ``start'' command.
1116 This command runs the program until the begining of the main procedure.
1118 * New BSD Kernel Data Access Library (libkvm) interface
1120 Using ``target kvm'' it is now possible to debug kernel core dumps and
1121 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1122 platforms. Currently supported (native-only) configurations are:
1124 FreeBSD/amd64 x86_64-*-freebsd*
1125 FreeBSD/i386 i?86-*-freebsd*
1126 NetBSD/i386 i?86-*-netbsd*
1127 NetBSD/m68k m68*-*-netbsd*
1128 NetBSD/sparc sparc-*-netbsd*
1129 OpenBSD/amd64 x86_64-*-openbsd*
1130 OpenBSD/i386 i?86-*-openbsd*
1131 OpenBSD/m68k m68*-openbsd*
1132 OpenBSD/sparc sparc-*-openbsd*
1134 * Signal trampoline code overhauled
1136 Many generic problems with GDB's signal handling code have been fixed.
1137 These include: backtraces through non-contiguous stacks; recognition
1138 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1139 call; backtrace through a signal trampoline; step into and out of
1140 signal handlers; and single-stepping in the signal trampoline.
1142 Please note that kernel bugs are a limiting factor here. These
1143 features have been shown to work on an s390 GNU/Linux system that
1144 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1146 * Cygwin support for DWARF 2 added.
1148 * New native configurations
1150 GNU/Linux/hppa hppa*-*-linux*
1151 OpenBSD/hppa hppa*-*-openbsd*
1152 OpenBSD/m68k m68*-*-openbsd*
1153 OpenBSD/m88k m88*-*-openbsd*
1154 OpenBSD/powerpc powerpc-*-openbsd*
1155 NetBSD/vax vax-*-netbsd*
1156 OpenBSD/vax vax-*-openbsd*
1158 * END-OF-LIFE frame compatibility module
1160 GDB's internal frame infrastructure has been completely rewritten.
1161 The new infrastructure making it possible to support key new features
1162 including DWARF 2 Call Frame Information. To aid in the task of
1163 migrating old configurations to this new infrastructure, a
1164 compatibility module, that allowed old configurations to continue to
1165 work, was also included.
1167 GDB 6.2 will be the last release to include this frame compatibility
1168 module. This change directly impacts the following configurations:
1178 Unless there is activity to revive these configurations, they will be
1179 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1181 * REMOVED configurations and files
1183 Sun 3, running SunOS 3 m68*-*-sunos3*
1184 Sun 3, running SunOS 4 m68*-*-sunos4*
1185 Sun 2, running SunOS 3 m68000-*-sunos3*
1186 Sun 2, running SunOS 4 m68000-*-sunos4*
1187 Motorola 680x0 running LynxOS m68*-*-lynxos*
1188 AT&T 3b1/Unix pc m68*-att-*
1189 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1190 decstation mips-dec-* mips-little-*
1191 riscos mips-*-riscos* mips-*-sysv*
1192 sonymips mips-sony-*
1193 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1195 *** Changes in GDB 6.1.1:
1197 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1199 The TUI (Text-mode User Interface) is now built as part of a default
1200 GDB configuration. It is enabled by either selecting the TUI with the
1201 command line option "-i=tui" or by running the separate "gdbtui"
1202 program. For more information on the TUI, see the manual "Debugging
1205 * Pending breakpoint support (also included in GDB 6.1)
1207 Support has been added to allow you to specify breakpoints in shared
1208 libraries that have not yet been loaded. If a breakpoint location
1209 cannot be found, and the "breakpoint pending" option is set to auto,
1210 GDB queries you if you wish to make the breakpoint pending on a future
1211 shared-library load. If and when GDB resolves the breakpoint symbol,
1212 the pending breakpoint is removed as one or more regular breakpoints
1215 Pending breakpoints are very useful for GCJ Java debugging.
1217 * Fixed ISO-C build problems
1219 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1220 non ISO-C code that stopped them being built using a more strict ISO-C
1221 compiler (e.g., IBM's C compiler).
1223 * Fixed build problem on IRIX 5
1225 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1226 wasn't able to compile compile on an IRIX 5 system.
1228 * Added execute permission to gdb/gdbserver/configure
1230 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1231 permission. This bug would cause configure to fail on a number of
1232 systems (Solaris, IRIX). Ref: server/519.
1234 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1236 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1237 has been updated to use constant array sizes.
1239 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1241 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1242 its generated DWARF Call Frame Info. This encoding was causing GDB to
1243 panic, that panic has been fixed. Ref: gdb/1628.
1245 * Fixed a problem when examining parameters in shared library code.
1247 When examining parameters in optimized shared library code generated
1248 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1249 not available''. GDB now correctly displays the variable's value.
1251 *** Changes in GDB 6.1:
1253 * Removed --with-mmalloc
1255 Support for the mmalloc memory manager has been removed, as it
1256 conflicted with the internal gdb byte cache.
1258 * Changes in AMD64 configurations
1260 The AMD64 target now includes the %cs and %ss registers. As a result
1261 the AMD64 remote protocol has changed; this affects the floating-point
1262 and SSE registers. If you rely on those registers for your debugging,
1263 you should upgrade gdbserver on the remote side.
1265 * Revised SPARC target
1267 The SPARC target has been completely revised, incorporating the
1268 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1269 support for LynxOS and SunOS 4 has been dropped. Calling functions
1270 from within GDB on operating systems with a non-executable stack
1271 (Solaris, OpenBSD) now works.
1275 GDB has a new C++ demangler which does a better job on the mangled
1276 names generated by current versions of g++. It also runs faster, so
1277 with this and other changes gdb should now start faster on large C++
1280 * DWARF 2 Location Expressions
1282 GDB support for location expressions has been extended to support function
1283 arguments and frame bases. Older versions of GDB could crash when they
1286 * C++ nested types and namespaces
1288 GDB's support for nested types and namespaces in C++ has been
1289 improved, especially if you use the DWARF 2 debugging format. (This
1290 is the default for recent versions of GCC on most platforms.)
1291 Specifically, if you have a class "Inner" defined within a class or
1292 namespace "Outer", then GDB realizes that the class's name is
1293 "Outer::Inner", not simply "Inner". This should greatly reduce the
1294 frequency of complaints about not finding RTTI symbols. In addition,
1295 if you are stopped at inside of a function defined within a namespace,
1296 GDB modifies its name lookup accordingly.
1298 * New native configurations
1300 NetBSD/amd64 x86_64-*-netbsd*
1301 OpenBSD/amd64 x86_64-*-openbsd*
1302 OpenBSD/alpha alpha*-*-openbsd*
1303 OpenBSD/sparc sparc-*-openbsd*
1304 OpenBSD/sparc64 sparc64-*-openbsd*
1306 * New debugging protocols
1308 M32R with SDI protocol m32r-*-elf*
1310 * "set prompt-escape-char" command deleted.
1312 The command "set prompt-escape-char" has been deleted. This command,
1313 and its very obscure effet on GDB's prompt, was never documented,
1314 tested, nor mentioned in the NEWS file.
1316 * OBSOLETE configurations and files
1318 Configurations that have been declared obsolete in this release have
1319 been commented out. Unless there is activity to revive these
1320 configurations, the next release of GDB will have their sources
1321 permanently REMOVED.
1323 Sun 3, running SunOS 3 m68*-*-sunos3*
1324 Sun 3, running SunOS 4 m68*-*-sunos4*
1325 Sun 2, running SunOS 3 m68000-*-sunos3*
1326 Sun 2, running SunOS 4 m68000-*-sunos4*
1327 Motorola 680x0 running LynxOS m68*-*-lynxos*
1328 AT&T 3b1/Unix pc m68*-att-*
1329 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1330 decstation mips-dec-* mips-little-*
1331 riscos mips-*-riscos* mips-*-sysv*
1332 sonymips mips-sony-*
1333 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1335 * REMOVED configurations and files
1337 SGI Irix-4.x mips-sgi-irix4 or iris4
1338 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1339 Z8000 simulator z8k-zilog-none or z8ksim
1340 Matsushita MN10200 w/simulator mn10200-*-*
1341 H8/500 simulator h8500-hitachi-hms or h8500hms
1342 HP/PA running BSD hppa*-*-bsd*
1343 HP/PA running OSF/1 hppa*-*-osf*
1344 HP/PA Pro target hppa*-*-pro*
1345 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1346 386BSD i[3456]86-*-bsd*
1347 Sequent family i[3456]86-sequent-sysv4*
1348 i[3456]86-sequent-sysv*
1349 i[3456]86-sequent-bsd*
1350 SPARC running LynxOS sparc-*-lynxos*
1351 SPARC running SunOS 4 sparc-*-sunos4*
1352 Tsqware Sparclet sparclet-*-*
1353 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1355 *** Changes in GDB 6.0:
1359 Support for debugging the Objective-C programming language has been
1360 integrated into GDB.
1362 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1364 DWARF 2's Call Frame Information makes available compiler generated
1365 information that more exactly describes the program's run-time stack.
1366 By using this information, GDB is able to provide more robust stack
1369 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1370 have been updated to use a new backtrace mechanism which includes
1371 DWARF 2 CFI support.
1375 GDB's remote protocol has been extended to include support for hosted
1376 file I/O (where the remote target uses GDB's file system). See GDB's
1377 remote protocol documentation for details.
1379 * All targets using the new architecture framework.
1381 All of GDB's targets have been updated to use the new internal
1382 architecture framework. The way is now open for future GDB releases
1383 to include cross-architecture native debugging support (i386 on amd64,
1386 * GNU/Linux's Thread Local Storage (TLS)
1388 GDB now includes support for for the GNU/Linux implementation of
1389 per-thread variables.
1391 * GNU/Linux's Native POSIX Thread Library (NPTL)
1393 GDB's thread code has been updated to work with either the new
1394 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1396 * Separate debug info.
1398 GDB, in conjunction with BINUTILS, now supports a mechanism for
1399 automatically loading debug information from a separate file. Instead
1400 of shipping full debug and non-debug versions of system libraries,
1401 system integrators can now instead ship just the stripped libraries
1402 and optional debug files.
1404 * DWARF 2 Location Expressions
1406 DWARF 2 Location Expressions allow the compiler to more completely
1407 describe the location of variables (even in optimized code) to the
1410 GDB now includes preliminary support for location expressions (support
1411 for DW_OP_piece is still missing).
1415 A number of long standing bugs that caused GDB to die while starting a
1416 Java application have been fixed. GDB's Java support is now
1417 considered "useable".
1419 * GNU/Linux support for fork, vfork, and exec.
1421 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1422 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1425 * GDB supports logging output to a file
1427 There are two new commands, "set logging" and "show logging", which can be
1428 used to capture GDB's output to a file.
1430 * The meaning of "detach" has changed for gdbserver
1432 The "detach" command will now resume the application, as documented. To
1433 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1436 * d10v, m68hc11 `regs' command deprecated
1438 The `info registers' command has been updated so that it displays the
1439 registers using a format identical to the old `regs' command.
1443 A new command, "maint set profile on/off", has been added. This command can
1444 be used to enable or disable profiling while running GDB, to profile a
1445 session or a set of commands. In addition there is a new configure switch,
1446 "--enable-profiling", which will cause GDB to be compiled with profiling
1447 data, for more informative profiling results.
1449 * Default MI syntax changed to "mi2".
1451 The default MI (machine interface) syntax, enabled by the command line
1452 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1453 "mi1", can be enabled by specifying the option "-i=mi1".
1455 Support for the original "mi0" syntax (included in GDB 5.0) has been
1458 Fix for gdb/192: removed extraneous space when displaying frame level.
1459 Fix for gdb/672: update changelist is now output in mi list format.
1460 Fix for gdb/702: a -var-assign that updates the value now shows up
1461 in a subsequent -var-update.
1463 * New native configurations.
1465 FreeBSD/amd64 x86_64-*-freebsd*
1467 * Multi-arched targets.
1469 HP/PA HPUX11 hppa*-*-hpux*
1470 Renesas M32R/D w/simulator m32r-*-elf*
1472 * OBSOLETE configurations and files
1474 Configurations that have been declared obsolete in this release have
1475 been commented out. Unless there is activity to revive these
1476 configurations, the next release of GDB will have their sources
1477 permanently REMOVED.
1479 Z8000 simulator z8k-zilog-none or z8ksim
1480 Matsushita MN10200 w/simulator mn10200-*-*
1481 H8/500 simulator h8500-hitachi-hms or h8500hms
1482 HP/PA running BSD hppa*-*-bsd*
1483 HP/PA running OSF/1 hppa*-*-osf*
1484 HP/PA Pro target hppa*-*-pro*
1485 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1486 Sequent family i[3456]86-sequent-sysv4*
1487 i[3456]86-sequent-sysv*
1488 i[3456]86-sequent-bsd*
1489 Tsqware Sparclet sparclet-*-*
1490 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1492 * REMOVED configurations and files
1495 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1496 IBM AIX PS/2 i[3456]86-*-aix
1497 i386 running Mach 3.0 i[3456]86-*-mach3*
1498 i386 running Mach i[3456]86-*-mach*
1499 i386 running OSF/1 i[3456]86-*osf1mk*
1500 HP/Apollo 68k Family m68*-apollo*-sysv*,
1502 m68*-hp-bsd*, m68*-hp-hpux*
1503 Argonaut Risc Chip (ARC) arc-*-*
1504 Mitsubishi D30V d30v-*-*
1505 Fujitsu FR30 fr30-*-elf*
1506 OS/9000 i[34]86-*-os9k
1507 I960 with MON960 i960-*-coff
1509 * MIPS $fp behavior changed
1511 The convenience variable $fp, for the MIPS, now consistently returns
1512 the address of the current frame's base. Previously, depending on the
1513 context, $fp could refer to either $sp or the current frame's base
1514 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1515 The GNU Source-Level Debugger''.
1517 *** Changes in GDB 5.3:
1519 * GNU/Linux shared library multi-threaded performance improved.
1521 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1522 `/proc', in preference to `ptrace' for memory reads. This may result
1523 in an improvement in the start-up time of multi-threaded, shared
1524 library applications when run under GDB. One GDB user writes: ``loads
1525 shared libs like mad''.
1527 * ``gdbserver'' now supports multi-threaded applications on some targets
1529 Support for debugging multi-threaded applications which use
1530 the GNU/Linux LinuxThreads package has been added for
1531 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1532 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1534 * GDB now supports C/C++ preprocessor macros.
1536 GDB now expands preprocessor macro invocations in C/C++ expressions,
1537 and provides various commands for showing macro definitions and how
1540 The new command `macro expand EXPRESSION' expands any macro
1541 invocations in expression, and shows the result.
1543 The new command `show macro MACRO-NAME' shows the definition of the
1544 macro named MACRO-NAME, and where it was defined.
1546 Most compilers don't include information about macros in the debugging
1547 information by default. In GCC 3.1, for example, you need to compile
1548 your program with the options `-gdwarf-2 -g3'. If the macro
1549 information is present in the executable, GDB will read it.
1551 * Multi-arched targets.
1553 DEC Alpha (partial) alpha*-*-*
1554 DEC VAX (partial) vax-*-*
1556 National Semiconductor NS32000 (partial) ns32k-*-*
1557 Motorola 68000 (partial) m68k-*-*
1558 Motorola MCORE mcore-*-*
1562 Fujitsu FRV architecture added by Red Hat frv*-*-*
1565 * New native configurations
1567 Alpha NetBSD alpha*-*-netbsd*
1568 SH NetBSD sh*-*-netbsdelf*
1569 MIPS NetBSD mips*-*-netbsd*
1570 UltraSPARC NetBSD sparc64-*-netbsd*
1572 * OBSOLETE configurations and files
1574 Configurations that have been declared obsolete in this release have
1575 been commented out. Unless there is activity to revive these
1576 configurations, the next release of GDB will have their sources
1577 permanently REMOVED.
1579 Mitsubishi D30V d30v-*-*
1580 OS/9000 i[34]86-*-os9k
1581 IBM AIX PS/2 i[3456]86-*-aix
1582 Fujitsu FR30 fr30-*-elf*
1583 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1584 Argonaut Risc Chip (ARC) arc-*-*
1585 i386 running Mach 3.0 i[3456]86-*-mach3*
1586 i386 running Mach i[3456]86-*-mach*
1587 i386 running OSF/1 i[3456]86-*osf1mk*
1588 HP/Apollo 68k Family m68*-apollo*-sysv*,
1590 m68*-hp-bsd*, m68*-hp-hpux*
1591 I960 with MON960 i960-*-coff
1593 * OBSOLETE languages
1595 CHILL, a Pascal like language used by telecommunications companies.
1597 * REMOVED configurations and files
1599 AMD 29k family via UDI a29k-amd-udi, udi29k
1600 A29K VxWorks a29k-*-vxworks
1601 AMD 29000 embedded, using EBMON a29k-none-none
1602 AMD 29000 embedded with COFF a29k-none-coff
1603 AMD 29000 embedded with a.out a29k-none-aout
1605 testsuite/gdb.hp/gdb.threads-hp/ directory
1607 * New command "set max-user-call-depth <nnn>"
1609 This command allows the user to limit the call depth of user-defined
1610 commands. The default is 1024.
1612 * Changes in FreeBSD/i386 native debugging.
1614 Support for the "generate-core-file" has been added.
1616 * New commands "dump", "append", and "restore".
1618 These commands allow data to be copied from target memory
1619 to a bfd-format or binary file (dump and append), and back
1620 from a file into memory (restore).
1622 * Improved "next/step" support on multi-processor Alpha Tru64.
1624 The previous single-step mechanism could cause unpredictable problems,
1625 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1626 of a software single-step mechanism prevents this.
1628 *** Changes in GDB 5.2.1:
1636 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1637 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1638 Fix, by Joel Brobecker imported from mainline.
1640 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1641 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1642 Fix, by Fred Fish, imported from mainline.
1644 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1645 Surprisingly enough, it works now.
1646 By Michal Ludvig, imported from mainline.
1648 i386 hardware watchpoint support:
1649 avoid misses on second run for some targets.
1650 By Pierre Muller, imported from mainline.
1652 *** Changes in GDB 5.2:
1654 * New command "set trust-readonly-sections on[off]".
1656 This command is a hint that tells gdb that read-only sections
1657 really are read-only (ie. that their contents will not change).
1658 In this mode, gdb will go to the object file rather than the
1659 target to read memory from read-only sections (such as ".text").
1660 This can be a significant performance improvement on some
1661 (notably embedded) targets.
1663 * New command "generate-core-file" (or "gcore").
1665 This new gdb command allows the user to drop a core file of the child
1666 process state at any time. So far it's been implemented only for
1667 GNU/Linux and Solaris, but should be relatively easily ported to other
1668 hosts. Argument is core file name (defaults to core.<pid>).
1670 * New command line option
1672 GDB now accepts --pid or -p followed by a process id.
1674 * Change in command line behavior -- corefiles vs. process ids.
1676 There is a subtle behavior in the way in which GDB handles
1677 command line arguments. The first non-flag argument is always
1678 a program to debug, but the second non-flag argument may either
1679 be a corefile or a process id. Previously, GDB would attempt to
1680 open the second argument as a corefile, and if that failed, would
1681 issue a superfluous error message and then attempt to attach it as
1682 a process. Now, if the second argument begins with a non-digit,
1683 it will be treated as a corefile. If it begins with a digit,
1684 GDB will attempt to attach it as a process, and if no such process
1685 is found, will then attempt to open it as a corefile.
1687 * Changes in ARM configurations.
1689 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1690 configuration is fully multi-arch.
1692 * New native configurations
1694 ARM NetBSD arm*-*-netbsd*
1695 x86 OpenBSD i[3456]86-*-openbsd*
1696 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1697 Sparc64 running FreeBSD sparc64-*-freebsd*
1701 Sanyo XStormy16 xstormy16-elf
1703 * OBSOLETE configurations and files
1705 Configurations that have been declared obsolete in this release have
1706 been commented out. Unless there is activity to revive these
1707 configurations, the next release of GDB will have their sources
1708 permanently REMOVED.
1710 AMD 29k family via UDI a29k-amd-udi, udi29k
1711 A29K VxWorks a29k-*-vxworks
1712 AMD 29000 embedded, using EBMON a29k-none-none
1713 AMD 29000 embedded with COFF a29k-none-coff
1714 AMD 29000 embedded with a.out a29k-none-aout
1716 testsuite/gdb.hp/gdb.threads-hp/ directory
1718 * REMOVED configurations and files
1720 TI TMS320C80 tic80-*-*
1722 PowerPC Solaris powerpcle-*-solaris*
1723 PowerPC Windows NT powerpcle-*-cygwin32
1724 PowerPC Netware powerpc-*-netware*
1725 Harris/CXUX m88k m88*-harris-cxux*
1726 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1727 ns32k-utek-sysv* ns32k-utek-*
1728 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1729 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1730 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1731 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1732 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1734 * Changes to command line processing
1736 The new `--args' feature can be used to specify command-line arguments
1737 for the inferior from gdb's command line.
1739 * Changes to key bindings
1741 There is a new `operate-and-get-next' function bound to `C-o'.
1743 *** Changes in GDB 5.1.1
1745 Fix compile problem on DJGPP.
1747 Fix a problem with floating-point registers on the i386 being
1750 Fix to stop GDB crashing on .debug_str debug info.
1752 Numerous documentation fixes.
1754 Numerous testsuite fixes.
1756 *** Changes in GDB 5.1:
1758 * New native configurations
1760 Alpha FreeBSD alpha*-*-freebsd*
1761 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1762 MIPS GNU/Linux mips*-*-linux*
1763 MIPS SGI Irix 6.x mips*-sgi-irix6*
1764 ia64 AIX ia64-*-aix*
1765 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1769 Motorola 68HC11 and 68HC12 m68hc11-elf
1771 UltraSparc running GNU/Linux sparc64-*-linux*
1773 * OBSOLETE configurations and files
1775 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1776 Harris/CXUX m88k m88*-harris-cxux*
1777 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1778 ns32k-utek-sysv* ns32k-utek-*
1779 TI TMS320C80 tic80-*-*
1781 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1782 PowerPC Solaris powerpcle-*-solaris*
1783 PowerPC Windows NT powerpcle-*-cygwin32
1784 PowerPC Netware powerpc-*-netware*
1785 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1786 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1787 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1788 Apple Macintosh (MPW) host N/A
1790 stuff.c (Program to stuff files into a specially prepared space in kdb)
1791 kdb-start.c (Main loop for the standalone kernel debugger)
1793 Configurations that have been declared obsolete in this release have
1794 been commented out. Unless there is activity to revive these
1795 configurations, the next release of GDB will have their sources
1796 permanently REMOVED.
1798 * REMOVED configurations and files
1800 Altos 3068 m68*-altos-*
1801 Convex c1-*-*, c2-*-*
1803 ARM RISCix arm-*-* (as host)
1807 * GDB has been converted to ISO C.
1809 GDB's source code has been converted to ISO C. In particular, the
1810 sources are fully protoized, and rely on standard headers being
1815 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1817 * The MI enabled by default.
1819 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1820 revised and enabled by default. Packages which use GDB as a debugging
1821 engine behind a UI or another front end are encouraged to switch to
1822 using the GDB/MI interface, instead of the old annotations interface
1823 which is now deprecated.
1825 * Support for debugging Pascal programs.
1827 GDB now includes support for debugging Pascal programs. The following
1828 main features are supported:
1830 - Pascal-specific data types such as sets;
1832 - automatic recognition of Pascal sources based on file-name
1835 - Pascal-style display of data types, variables, and functions;
1837 - a Pascal expression parser.
1839 However, some important features are not yet supported.
1841 - Pascal string operations are not supported at all;
1843 - there are some problems with boolean types;
1845 - Pascal type hexadecimal constants are not supported
1846 because they conflict with the internal variables format;
1848 - support for Pascal objects and classes is not full yet;
1850 - unlike Pascal, GDB is case-sensitive for symbol names.
1852 * Changes in completion.
1854 Commands such as `shell', `run' and `set args', which pass arguments
1855 to inferior programs, now complete on file names, similar to what
1856 users expect at the shell prompt.
1858 Commands which accept locations, such as `disassemble', `print',
1859 `breakpoint', `until', etc. now complete on filenames as well as
1860 program symbols. Thus, if you type "break foob TAB", and the source
1861 files linked into the programs include `foobar.c', that file name will
1862 be one of the candidates for completion. However, file names are not
1863 considered for completion after you typed a colon that delimits a file
1864 name from a name of a function in that file, as in "break foo.c:bar".
1866 `set demangle-style' completes on available demangling styles.
1868 * New platform-independent commands:
1870 It is now possible to define a post-hook for a command as well as a
1871 hook that runs before the command. For more details, see the
1872 documentation of `hookpost' in the GDB manual.
1874 * Changes in GNU/Linux native debugging.
1876 Support for debugging multi-threaded programs has been completely
1877 revised for all platforms except m68k and sparc. You can now debug as
1878 many threads as your system allows you to have.
1880 Attach/detach is supported for multi-threaded programs.
1882 Support for SSE registers was added for x86. This doesn't work for
1883 multi-threaded programs though.
1885 * Changes in MIPS configurations.
1887 Multi-arch support is enabled for all MIPS configurations.
1889 GDB can now be built as native debugger on SGI Irix 6.x systems for
1890 debugging n32 executables. (Debugging 64-bit executables is not yet
1893 * Unified support for hardware watchpoints in all x86 configurations.
1895 Most (if not all) native x86 configurations support hardware-assisted
1896 breakpoints and watchpoints in a unified manner. This support
1897 implements debug register sharing between watchpoints, which allows to
1898 put a virtually infinite number of watchpoints on the same address,
1899 and also supports watching regions up to 16 bytes with several debug
1902 The new maintenance command `maintenance show-debug-regs' toggles
1903 debugging print-outs in functions that insert, remove, and test
1904 watchpoints and hardware breakpoints.
1906 * Changes in the DJGPP native configuration.
1908 New command ``info dos sysinfo'' displays assorted information about
1909 the CPU, OS, memory, and DPMI server.
1911 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1912 display information about segment descriptors stored in GDT, LDT, and
1915 New commands ``info dos pde'' and ``info dos pte'' display entries
1916 from Page Directory and Page Tables (for now works with CWSDPMI only).
1917 New command ``info dos address-pte'' displays the Page Table entry for
1918 a given linear address.
1920 GDB can now pass command lines longer than 126 characters to the
1921 program being debugged (requires an update to the libdbg.a library
1922 which is part of the DJGPP development kit).
1924 DWARF2 debug info is now supported.
1926 It is now possible to `step' and `next' through calls to `longjmp'.
1928 * Changes in documentation.
1930 All GDB documentation was converted to GFDL, the GNU Free
1931 Documentation License.
1933 Tracepoints-related commands are now fully documented in the GDB
1936 TUI, the Text-mode User Interface, is now documented in the manual.
1938 Tracepoints-related commands are now fully documented in the GDB
1941 The "GDB Internals" manual now has an index. It also includes
1942 documentation of `ui_out' functions, GDB coding standards, x86
1943 hardware watchpoints, and memory region attributes.
1945 * GDB's version number moved to ``version.in''
1947 The Makefile variable VERSION has been replaced by the file
1948 ``version.in''. People creating GDB distributions should update the
1949 contents of this file.
1953 GUD support is now a standard part of the EMACS distribution.
1955 *** Changes in GDB 5.0:
1957 * Improved support for debugging FP programs on x86 targets
1959 Unified and much-improved support for debugging floating-point
1960 programs on all x86 targets. In particular, ``info float'' now
1961 displays the FP registers in the same format on all x86 targets, with
1962 greater level of detail.
1964 * Improvements and bugfixes in hardware-assisted watchpoints
1966 It is now possible to watch array elements, struct members, and
1967 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1968 on x86 targets no longer erroneously trigger when the address is
1971 * Improvements in the native DJGPP version of GDB
1973 The distribution now includes all the scripts and auxiliary files
1974 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1975 machines ``out of the box''.
1977 The DJGPP version can now debug programs that use signals. It is
1978 possible to catch signals that happened in the debuggee, deliver
1979 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1980 would kill the program being debugged.) Programs that hook hardware
1981 interrupts (keyboard, timer, etc.) can also be debugged.
1983 It is now possible to debug DJGPP programs that redirect their
1984 standard handles or switch them to raw (as opposed to cooked) mode, or
1985 even close them. The command ``run < foo > bar'' works as expected,
1986 and ``info terminal'' reports useful information about the debuggee's
1987 terminal, including raw/cooked mode, redirection, etc.
1989 The DJGPP version now uses termios functions for console I/O, which
1990 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1993 DOS-style file names with drive letters are now fully supported by
1996 It is now possible to debug DJGPP programs that switch their working
1997 directory. It is also possible to rerun the debuggee any number of
1998 times without restarting GDB; thus, you can use the same setup,
1999 breakpoints, etc. for many debugging sessions.
2001 * New native configurations
2003 ARM GNU/Linux arm*-*-linux*
2004 PowerPC GNU/Linux powerpc-*-linux*
2008 Motorola MCore mcore-*-*
2009 x86 VxWorks i[3456]86-*-vxworks*
2010 PowerPC VxWorks powerpc-*-vxworks*
2011 TI TMS320C80 tic80-*-*
2013 * OBSOLETE configurations
2015 Altos 3068 m68*-altos-*
2016 Convex c1-*-*, c2-*-*
2018 ARM RISCix arm-*-* (as host)
2021 Configurations that have been declared obsolete will be commented out,
2022 but the code will be left in place. If there is no activity to revive
2023 these configurations before the next release of GDB, the sources will
2024 be permanently REMOVED.
2026 * Gould support removed
2028 Support for the Gould PowerNode and NP1 has been removed.
2030 * New features for SVR4
2032 On SVR4 native platforms (such as Solaris), if you attach to a process
2033 without first loading a symbol file, GDB will now attempt to locate and
2034 load symbols from the running process's executable file.
2036 * Many C++ enhancements
2038 C++ support has been greatly improved. Overload resolution now works properly
2039 in almost all cases. RTTI support is on the way.
2041 * Remote targets can connect to a sub-program
2043 A popen(3) style serial-device has been added. This device starts a
2044 sub-process (such as a stand-alone simulator) and then communicates
2045 with that. The sub-program to run is specified using the syntax
2046 ``|<program> <args>'' vis:
2048 (gdb) set remotedebug 1
2049 (gdb) target extended-remote |mn10300-elf-sim program-args
2051 * MIPS 64 remote protocol
2053 A long standing bug in the mips64 remote protocol where by GDB
2054 expected certain 32 bit registers (ex SR) to be transfered as 32
2055 instead of 64 bits has been fixed.
2057 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2058 added to provide backward compatibility with older versions of GDB.
2060 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2062 The command ``set remotebinarydownload'' command has been replaced by
2063 ``set remote X-packet''. Other commands in ``set remote'' family
2064 include ``set remote P-packet''.
2066 * Breakpoint commands accept ranges.
2068 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2069 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2070 ``tracepoint passcount'' also accepts a range of tracepoints.
2072 * ``apropos'' command added.
2074 The ``apropos'' command searches through command names and
2075 documentation strings, printing out matches, making it much easier to
2076 try to find a command that does what you are looking for.
2080 A new machine oriented interface (MI) has been added to GDB. This
2081 interface is designed for debug environments running GDB as a separate
2082 process. This is part of the long term libGDB project. See the
2083 "GDB/MI" chapter of the GDB manual for further information. It can be
2084 enabled by configuring with:
2086 .../configure --enable-gdbmi
2088 *** Changes in GDB-4.18:
2090 * New native configurations
2092 HP-UX 10.20 hppa*-*-hpux10.20
2093 HP-UX 11.x hppa*-*-hpux11.0*
2094 M68K GNU/Linux m68*-*-linux*
2098 Fujitsu FR30 fr30-*-elf*
2099 Intel StrongARM strongarm-*-*
2100 Mitsubishi D30V d30v-*-*
2102 * OBSOLETE configurations
2104 Gould PowerNode, NP1 np1-*-*, pn-*-*
2106 Configurations that have been declared obsolete will be commented out,
2107 but the code will be left in place. If there is no activity to revive
2108 these configurations before the next release of GDB, the sources will
2109 be permanently REMOVED.
2113 As a compatibility experiment, GDB's source files buildsym.h and
2114 buildsym.c have been converted to pure standard C, no longer
2115 containing any K&R compatibility code. We believe that all systems in
2116 use today either come with a standard C compiler, or have a GCC port
2117 available. If this is not true, please report the affected
2118 configuration to bug-gdb@gnu.org immediately. See the README file for
2119 information about getting a standard C compiler if you don't have one
2124 GDB now uses readline 2.2.
2126 * set extension-language
2128 You can now control the mapping between filename extensions and source
2129 languages by using the `set extension-language' command. For instance,
2130 you can ask GDB to treat .c files as C++ by saying
2131 set extension-language .c c++
2132 The command `info extensions' lists all of the recognized extensions
2133 and their associated languages.
2135 * Setting processor type for PowerPC and RS/6000
2137 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2138 you can use the `set processor' command to specify what variant of the
2139 PowerPC family you are debugging. The command
2143 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2144 following PowerPC and RS6000 variants:
2146 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2147 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2149 403GC IBM PowerPC 403GC
2150 505 Motorola PowerPC 505
2151 860 Motorola PowerPC 860 or 850
2152 601 Motorola PowerPC 601
2153 602 Motorola PowerPC 602
2154 603 Motorola/IBM PowerPC 603 or 603e
2155 604 Motorola PowerPC 604 or 604e
2156 750 Motorola/IBM PowerPC 750 or 750
2158 At the moment, this command just tells GDB what to name the
2159 special-purpose processor registers. Since almost all the affected
2160 registers are inaccessible to user-level programs, this command is
2161 only useful for remote debugging in its present form.
2165 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2166 more extensive support for HP-UX. Added features include shared
2167 library support, kernel threads and hardware watchpoints for 11.00,
2168 support for HP's ANSI C and C++ compilers, and a compatibility mode
2169 for xdb and dbx commands.
2173 HP's donation includes the new concept of catchpoints, which is a
2174 generalization of the old catch command. On HP-UX, it is now possible
2175 to catch exec, fork, and vfork, as well as library loading.
2177 This means that the existing catch command has changed; its first
2178 argument now specifies the type of catch to be set up. See the
2179 output of "help catch" for a list of catchpoint types.
2181 * Debugging across forks
2183 On HP-UX, you can choose which process to debug when a fork() happens
2188 HP has donated a curses-based terminal user interface (TUI). To get
2189 it, build with --enable-tui. Although this can be enabled for any
2190 configuration, at present it only works for native HP debugging.
2192 * GDB remote protocol additions
2194 A new protocol packet 'X' that writes binary data is now available.
2195 Default behavior is to try 'X', then drop back to 'M' if the stub
2196 fails to respond. The settable variable `remotebinarydownload'
2197 allows explicit control over the use of 'X'.
2199 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2200 full 64-bit address. The command
2202 set remoteaddresssize 32
2204 can be used to revert to the old behaviour. For existing remote stubs
2205 the change should not be noticed, as the additional address information
2208 In order to assist in debugging stubs, you may use the maintenance
2209 command `packet' to send any text string to the stub. For instance,
2211 maint packet heythere
2213 sends the packet "$heythere#<checksum>". Note that it is very easy to
2214 disrupt a debugging session by sending the wrong packet at the wrong
2217 The compare-sections command allows you to compare section data on the
2218 target to what is in the executable file without uploading or
2219 downloading, by comparing CRC checksums.
2221 * Tracing can collect general expressions
2223 You may now collect general expressions at tracepoints. This requires
2224 further additions to the target-side stub; see tracepoint.c and
2225 doc/agentexpr.texi for further details.
2227 * mask-address variable for Mips
2229 For Mips targets, you may control the zeroing of the upper 32 bits of
2230 a 64-bit address by entering `set mask-address on'. This is mainly
2231 of interest to users of embedded R4xxx and R5xxx processors.
2233 * Higher serial baud rates
2235 GDB's serial code now allows you to specify baud rates 57600, 115200,
2236 230400, and 460800 baud. (Note that your host system may not be able
2237 to achieve all of these rates.)
2241 The i960 configuration now includes an initial implementation of a
2242 builtin simulator, contributed by Jim Wilson.
2245 *** Changes in GDB-4.17:
2247 * New native configurations
2249 Alpha GNU/Linux alpha*-*-linux*
2250 Unixware 2.x i[3456]86-unixware2*
2251 Irix 6.x mips*-sgi-irix6*
2252 PowerPC GNU/Linux powerpc-*-linux*
2253 PowerPC Solaris powerpcle-*-solaris*
2254 Sparc GNU/Linux sparc-*-linux*
2255 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2259 Argonaut Risc Chip (ARC) arc-*-*
2260 Hitachi H8/300S h8300*-*-*
2261 Matsushita MN10200 w/simulator mn10200-*-*
2262 Matsushita MN10300 w/simulator mn10300-*-*
2263 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2264 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2265 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2266 Mitsubishi D10V w/simulator d10v-*-*
2267 Mitsubishi M32R/D w/simulator m32r-*-elf*
2268 Tsqware Sparclet sparclet-*-*
2269 NEC V850 w/simulator v850-*-*
2271 * New debugging protocols
2273 ARM with RDI protocol arm*-*-*
2274 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2275 DDB and LSI variants of PMON protocol mips*-*-*
2276 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2277 PowerPC with SDS protocol powerpc{,le}-*-eabi
2278 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2282 All configurations can now understand and use the DWARF 2 debugging
2283 format. The choice is automatic, if the symbol file contains DWARF 2
2288 GDB now includes basic Java language support. This support is
2289 only useful with Java compilers that produce native machine code.
2291 * solib-absolute-prefix and solib-search-path
2293 For SunOS and SVR4 shared libraries, you may now set the prefix for
2294 loading absolute shared library symbol files, and the search path for
2295 locating non-absolute shared library symbol files.
2297 * Live range splitting
2299 GDB can now effectively debug code for which GCC has performed live
2300 range splitting as part of its optimization. See gdb/doc/LRS for
2301 more details on the expected format of the stabs information.
2305 GDB's support for the GNU Hurd, including thread debugging, has been
2306 updated to work with current versions of the Hurd.
2310 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2311 instruction set. ARM GDB automatically detects when Thumb
2312 instructions are in use, and adjusts disassembly and backtracing
2317 GDB's MIPS target configurations now handle the MIP16 16-bit
2322 GDB now includes support for overlays; if an executable has been
2323 linked such that multiple sections are based at the same address, GDB
2324 will decide which section to use for symbolic info. You can choose to
2325 control the decision manually, using overlay commands, or implement
2326 additional target-side support and use "overlay load-target" to bring
2327 in the overlay mapping. Do "help overlay" for more detail.
2331 The command "info symbol <address>" displays information about
2332 the symbol at the specified address.
2336 The standard remote protocol now includes an extension that allows
2337 asynchronous collection and display of trace data. This requires
2338 extensive support in the target-side debugging stub. Tracing mode
2339 includes a new interaction mode in GDB and new commands: see the
2340 file tracepoint.c for more details.
2344 Configurations for embedded MIPS now include a simulator contributed
2345 by Cygnus Solutions. The simulator supports the instruction sets
2346 of most MIPS variants.
2350 Sparc configurations may now include the ERC32 simulator contributed
2351 by the European Space Agency. The simulator is not built into
2352 Sparc targets by default; configure with --enable-sim to include it.
2356 For target configurations that may include multiple variants of a
2357 basic architecture (such as MIPS and SH), you may now set the
2358 architecture explicitly. "set arch" sets, "info arch" lists
2359 the possible architectures.
2361 *** Changes in GDB-4.16:
2363 * New native configurations
2365 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2366 M68K NetBSD m68k-*-netbsd*
2367 PowerPC AIX 4.x powerpc-*-aix*
2368 PowerPC MacOS powerpc-*-macos*
2369 PowerPC Windows NT powerpcle-*-cygwin32
2370 RS/6000 AIX 4.x rs6000-*-aix4*
2374 ARM with RDP protocol arm-*-*
2375 I960 with MON960 i960-*-coff
2376 MIPS VxWorks mips*-*-vxworks*
2377 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2378 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2380 Matra Sparclet sparclet-*-*
2384 The powerpc-eabi configuration now includes the PSIM simulator,
2385 contributed by Andrew Cagney, with assistance from Mike Meissner.
2386 PSIM is a very elaborate model of the PowerPC, including not only
2387 basic instruction set execution, but also details of execution unit
2388 performance and I/O hardware. See sim/ppc/README for more details.
2392 GDB now works with Solaris 2.5.
2394 * Windows 95/NT native
2396 GDB will now work as a native debugger on Windows 95 and Windows NT.
2397 To build it from source, you must use the "gnu-win32" environment,
2398 which uses a DLL to emulate enough of Unix to run the GNU tools.
2399 Further information, binaries, and sources are available at
2400 ftp.cygnus.com, under pub/gnu-win32.
2402 * dont-repeat command
2404 If a user-defined command includes the command `dont-repeat', then the
2405 command will not be repeated if the user just types return. This is
2406 useful if the command is time-consuming to run, so that accidental
2407 extra keystrokes don't run the same command many times.
2409 * Send break instead of ^C
2411 The standard remote protocol now includes an option to send a break
2412 rather than a ^C to the target in order to interrupt it. By default,
2413 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2415 * Remote protocol timeout
2417 The standard remote protocol includes a new variable `remotetimeout'
2418 that allows you to set the number of seconds before GDB gives up trying
2419 to read from the target. The default value is 2.
2421 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2423 By default GDB will automatically keep track of objects as they are
2424 loaded and unloaded by the dynamic linker. By using the command `set
2425 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2426 when shared library events occur, thus allowing you to set breakpoints
2427 in shared libraries which are explicitly loaded by the inferior.
2429 Note this feature does not work on hpux8. On hpux9 you must link
2430 /usr/lib/end.o into your program. This feature should work
2431 automatically on hpux10.
2433 * Irix 5.x hardware watchpoint support
2435 Irix 5 configurations now support the use of hardware watchpoints.
2437 * Mips protocol "SYN garbage limit"
2439 When debugging a Mips target using the `target mips' protocol, you
2440 may set the number of characters that GDB will ignore by setting
2441 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2442 every character. The default value is 1050.
2444 * Recording and replaying remote debug sessions
2446 If you set `remotelogfile' to the name of a file, gdb will write to it
2447 a recording of a remote debug session. This recording may then be
2448 replayed back to gdb using "gdbreplay". See gdbserver/README for
2449 details. This is useful when you have a problem with GDB while doing
2450 remote debugging; you can make a recording of the session and send it
2451 to someone else, who can then recreate the problem.
2453 * Speedups for remote debugging
2455 GDB includes speedups for downloading and stepping MIPS systems using
2456 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2457 and more efficient S-record downloading.
2459 * Memory use reductions and statistics collection
2461 GDB now uses less memory and reports statistics about memory usage.
2462 Try the `maint print statistics' command, for example.
2464 *** Changes in GDB-4.15:
2466 * Psymtabs for XCOFF
2468 The symbol reader for AIX GDB now uses partial symbol tables. This
2469 can greatly improve startup time, especially for large executables.
2471 * Remote targets use caching
2473 Remote targets now use a data cache to speed up communication with the
2474 remote side. The data cache could lead to incorrect results because
2475 it doesn't know about volatile variables, thus making it impossible to
2476 debug targets which use memory mapped I/O devices. `set remotecache
2477 off' turns the the data cache off.
2479 * Remote targets may have threads
2481 The standard remote protocol now includes support for multiple threads
2482 in the target system, using new protocol commands 'H' and 'T'. See
2483 gdb/remote.c for details.
2487 If GDB is configured with `--enable-netrom', then it will include
2488 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2489 acts as though it is a bank of ROM on the target board, but you can
2490 write into it over the network. GDB's support consists only of
2491 support for fast loading into the emulated ROM; to debug, you must use
2492 another protocol, such as standard remote protocol. The usual
2493 sequence is something like
2495 target nrom <netrom-hostname>
2497 target remote <netrom-hostname>:1235
2501 GDB now includes support for the Apple Macintosh, as a host only. It
2502 may be run as either an MPW tool or as a standalone application, and
2503 it can debug through the serial port. All the usual GDB commands are
2504 available, but to the target command, you must supply "serial" as the
2505 device type instead of "/dev/ttyXX". See mpw-README in the main
2506 directory for more information on how to build. The MPW configuration
2507 scripts */mpw-config.in support only a few targets, and only the
2508 mips-idt-ecoff target has been tested.
2512 GDB configuration now uses autoconf. This is not user-visible,
2513 but does simplify configuration and building.
2517 GDB now supports hpux10.
2519 *** Changes in GDB-4.14:
2521 * New native configurations
2523 x86 FreeBSD i[345]86-*-freebsd
2524 x86 NetBSD i[345]86-*-netbsd
2525 NS32k NetBSD ns32k-*-netbsd
2526 Sparc NetBSD sparc-*-netbsd
2530 A29K VxWorks a29k-*-vxworks
2531 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2532 CPU32 EST-300 emulator m68*-*-est*
2533 PowerPC ELF powerpc-*-elf
2536 * Alpha OSF/1 support for procfs
2538 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2539 possible to attach to running processes. As the mounting of the /proc
2540 filesystem is optional on the Alpha, GDB automatically determines
2541 the availability of /proc during startup. This can lead to problems
2542 if /proc is unmounted after GDB has been started.
2544 * Arguments to user-defined commands
2546 User commands may accept up to 10 arguments separated by whitespace.
2547 Arguments are accessed within the user command via $arg0..$arg9. A
2550 print $arg0 + $arg1 + $arg2
2552 To execute the command use:
2555 Defines the command "adder" which prints the sum of its three arguments.
2556 Note the arguments are text substitutions, so they may reference variables,
2557 use complex expressions, or even perform inferior function calls.
2559 * New `if' and `while' commands
2561 This makes it possible to write more sophisticated user-defined
2562 commands. Both commands take a single argument, which is the
2563 expression to evaluate, and must be followed by the commands to
2564 execute, one per line, if the expression is nonzero, the list being
2565 terminated by the word `end'. The `if' command list may include an
2566 `else' word, which causes the following commands to be executed only
2567 if the expression is zero.
2569 * Fortran source language mode
2571 GDB now includes partial support for Fortran 77. It will recognize
2572 Fortran programs and can evaluate a subset of Fortran expressions, but
2573 variables and functions may not be handled correctly. GDB will work
2574 with G77, but does not yet know much about symbols emitted by other
2577 * Better HPUX support
2579 Most debugging facilities now work on dynamic executables for HPPAs
2580 running hpux9 or later. You can attach to running dynamically linked
2581 processes, but by default the dynamic libraries will be read-only, so
2582 for instance you won't be able to put breakpoints in them. To change
2583 that behavior do the following before running the program:
2589 This will cause the libraries to be mapped private and read-write.
2590 To revert to the normal behavior, do this:
2596 You cannot set breakpoints or examine data in the library until after
2597 the library is loaded if the function/data symbols do not have
2600 GDB can now also read debug symbols produced by the HP C compiler on
2601 HPPAs (sorry, no C++, Fortran or 68k support).
2603 * Target byte order now dynamically selectable
2605 You can choose which byte order to use with a target system, via the
2606 commands "set endian big" and "set endian little", and you can see the
2607 current setting by using "show endian". You can also give the command
2608 "set endian auto", in which case GDB will use the byte order
2609 associated with the executable. Currently, only embedded MIPS
2610 configurations support dynamic selection of target byte order.
2612 * New DOS host serial code
2614 This version uses DPMI interrupts to handle buffered I/O, so you
2615 no longer need to run asynctsr when debugging boards connected to
2618 *** Changes in GDB-4.13:
2620 * New "complete" command
2622 This lists all the possible completions for the rest of the line, if it
2623 were to be given as a command itself. This is intended for use by emacs.
2625 * Trailing space optional in prompt
2627 "set prompt" no longer adds a space for you after the prompt you set. This
2628 allows you to set a prompt which ends in a space or one that does not.
2630 * Breakpoint hit counts
2632 "info break" now displays a count of the number of times the breakpoint
2633 has been hit. This is especially useful in conjunction with "ignore"; you
2634 can ignore a large number of breakpoint hits, look at the breakpoint info
2635 to see how many times the breakpoint was hit, then run again, ignoring one
2636 less than that number, and this will get you quickly to the last hit of
2639 * Ability to stop printing at NULL character
2641 "set print null-stop" will cause GDB to stop printing the characters of
2642 an array when the first NULL is encountered. This is useful when large
2643 arrays actually contain only short strings.
2645 * Shared library breakpoints
2647 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2648 breakpoints in shared libraries before the executable is run.
2650 * Hardware watchpoints
2652 There is a new hardware breakpoint for the watch command for sparclite
2653 targets. See gdb/sparclite/hw_breakpoint.note.
2655 Hardware watchpoints are also now supported under GNU/Linux.
2659 Annotations have been added. These are for use with graphical interfaces,
2660 and are still experimental. Currently only gdba.el uses these.
2662 * Improved Irix 5 support
2664 GDB now works properly with Irix 5.2.
2666 * Improved HPPA support
2668 GDB now works properly with the latest GCC and GAS.
2670 * New native configurations
2672 Sequent PTX4 i[34]86-sequent-ptx4
2673 HPPA running OSF/1 hppa*-*-osf*
2674 Atari TT running SVR4 m68*-*-sysv4*
2675 RS/6000 LynxOS rs6000-*-lynxos*
2679 OS/9000 i[34]86-*-os9k
2680 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2683 * Hitachi SH7000 and E7000-PC ICE support
2685 There is now support for communicating with the Hitachi E7000-PC ICE.
2686 This is available automatically when GDB is configured for the SH.
2690 As usual, a variety of small fixes and improvements, both generic
2691 and configuration-specific. See the ChangeLog for more detail.
2693 *** Changes in GDB-4.12:
2695 * Irix 5 is now supported
2699 GDB-4.12 on the HPPA has a number of changes which make it unable
2700 to debug the output from the currently released versions of GCC and
2701 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2702 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2703 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2706 *** Changes in GDB-4.11:
2708 * User visible changes:
2712 The "set remotedebug" option is now consistent between the mips remote
2713 target, remote targets using the gdb-specific protocol, UDI (AMD's
2714 debug protocol for the 29k) and the 88k bug monitor. It is now an
2715 integer specifying a debug level (normally 0 or 1, but 2 means more
2716 debugging info for the mips target).
2718 * DEC Alpha native support
2720 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2721 debug info, but GDB works fairly well with the DEC compiler and should
2722 work with a future GCC release. See the README file for a few
2723 Alpha-specific notes.
2725 * Preliminary thread implementation
2727 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2729 * LynxOS native and target support for 386
2731 This release has been hosted on LynxOS 2.2, and also can be configured
2732 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2735 * Improvements in C++ mangling/demangling.
2737 This release has much better g++ debugging, specifically in name
2738 mangling/demangling, virtual function calls, print virtual table,
2739 call methods, ...etc.
2741 *** Changes in GDB-4.10:
2743 * User visible changes:
2745 Remote debugging using the GDB-specific (`target remote') protocol now
2746 supports the `load' command. This is only useful if you have some
2747 other way of getting the stub to the target system, and you can put it
2748 somewhere in memory where it won't get clobbered by the download.
2750 Filename completion now works.
2752 When run under emacs mode, the "info line" command now causes the
2753 arrow to point to the line specified. Also, "info line" prints
2754 addresses in symbolic form (as well as hex).
2756 All vxworks based targets now support a user settable option, called
2757 vxworks-timeout. This option represents the number of seconds gdb
2758 should wait for responses to rpc's. You might want to use this if
2759 your vxworks target is, perhaps, a slow software simulator or happens
2760 to be on the far side of a thin network line.
2764 This release contains support for using a DEC alpha as a GDB host for
2765 cross debugging. Native alpha debugging is not supported yet.
2768 *** Changes in GDB-4.9:
2772 This is the first GDB release which is accompanied by a matching testsuite.
2773 The testsuite requires installation of dejagnu, which should be available
2774 via ftp from most sites that carry GNU software.
2778 'Cfront' style demangling has had its name changed to 'ARM' style, to
2779 emphasize that it was written from the specifications in the C++ Annotated
2780 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2781 disclaimers, it still generated too much confusion with users attempting to
2782 use gdb with AT&T cfront.
2786 GDB now uses a standard remote interface to a simulator library.
2787 So far, the library contains simulators for the Zilog Z8001/2, the
2788 Hitachi H8/300, H8/500 and Super-H.
2790 * New targets supported
2792 H8/300 simulator h8300-hitachi-hms or h8300hms
2793 H8/500 simulator h8500-hitachi-hms or h8500hms
2794 SH simulator sh-hitachi-hms or sh
2795 Z8000 simulator z8k-zilog-none or z8ksim
2796 IDT MIPS board over serial line mips-idt-ecoff
2798 Cross-debugging to GO32 targets is supported. It requires a custom
2799 version of the i386-stub.c module which is integrated with the
2800 GO32 memory extender.
2802 * New remote protocols
2804 MIPS remote debugging protocol.
2806 * New source languages supported
2808 This version includes preliminary support for Chill, a Pascal like language
2809 used by telecommunications companies. Chill support is also being integrated
2810 into the GNU compiler, but we don't know when it will be publically available.
2813 *** Changes in GDB-4.8:
2815 * HP Precision Architecture supported
2817 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2818 version of this support was available as a set of patches from the
2819 University of Utah. GDB does not support debugging of programs
2820 compiled with the HP compiler, because HP will not document their file
2821 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2822 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2824 Many problems in the preliminary version have been fixed.
2826 * Faster and better demangling
2828 We have improved template demangling and fixed numerous bugs in the GNU style
2829 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2830 character types (wchar_t) are now supported. Demangling of each symbol is now
2831 only done once, and is cached when the symbol table for a file is read in.
2832 This results in a small increase in memory usage for C programs, a moderate
2833 increase in memory usage for C++ programs, and a fantastic speedup in
2836 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2837 from the specifications in the Annotated Reference Manual, which AT&T's
2838 compiler does not actually implement.
2840 * G++ multiple inheritance compiler problem
2842 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2843 inheritance lattices was reworked to properly discover ambiguities. We
2844 recently found an example which causes this new algorithm to fail in a
2845 very subtle way, producing bad debug information for those classes.
2846 The file 'gcc.patch' (in this directory) can be applied to gcc to
2847 circumvent the problem. A future GCC release will contain a complete
2850 The previous G++ debug info problem (mentioned below for the gdb-4.7
2851 release) is fixed in gcc version 2.3.2.
2853 * Improved configure script
2855 The `configure' script will now attempt to guess your system type if
2856 you don't supply a host system type. The old scheme of supplying a
2857 host system triplet is preferable over using this. All the magic is
2858 done in the new `config.guess' script. Examine it for details.
2860 We have also brought our configure script much more in line with the FSF's
2861 version. It now supports the --with-xxx options. In particular,
2862 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2863 The resulting GDB will not be able to read arbitrary object file formats --
2864 only the format ``expected'' to be used on the configured target system.
2865 We hope to make this the default in a future release.
2867 * Documentation improvements
2869 There's new internal documentation on how to modify GDB, and how to
2870 produce clean changes to the code. We implore people to read it
2871 before submitting changes.
2873 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2874 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2875 `info' files are also provided. To build `info' files from scratch,
2876 you will need the latest `makeinfo' release, which will be available in
2877 a future texinfo-X.Y release.
2879 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2880 We're not sure exactly which versions have this problem, but it has
2881 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2882 or better. If that isn't possible, there is a patch in
2883 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2884 around this problem.
2888 GDB now supports array constants that can be used in expressions typed in by
2889 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2890 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2893 The new directory `gdb/sparclite' contains a program that demonstrates
2894 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2896 * New native hosts supported
2898 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2899 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2901 * New targets supported
2903 AMD 29k family via UDI a29k-amd-udi or udi29k
2905 * New file formats supported
2907 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2908 HPUX core files, and SCO 3.2v2 core files.
2912 Attaching to processes now works again; thanks for the many bug reports.
2914 We have also stomped on a bunch of core dumps caused by
2915 printf_filtered("%s") problems.
2917 We eliminated a copyright problem on the rpc and ptrace header files
2918 for VxWorks, which was discovered at the last minute during the 4.7
2919 release. You should now be able to build a VxWorks GDB.
2921 You can now interrupt gdb while an attached process is running. This
2922 will cause the attached process to stop, and give control back to GDB.
2924 We fixed problems caused by using too many file descriptors
2925 for reading symbols from object files and libraries. This was
2926 especially a problem for programs that used many (~100) shared
2929 The `step' command now only enters a subroutine if there is line number
2930 information for the subroutine. Otherwise it acts like the `next'
2931 command. Previously, `step' would enter subroutines if there was
2932 any debugging information about the routine. This avoids problems
2933 when using `cc -g1' on MIPS machines.
2935 * Internal improvements
2937 GDB's internal interfaces have been improved to make it easier to support
2938 debugging of multiple languages in the future.
2940 GDB now uses a common structure for symbol information internally.
2941 Minimal symbols (derived from linkage symbols in object files), partial
2942 symbols (from a quick scan of debug information), and full symbols
2943 contain a common subset of information, making it easier to write
2944 shared code that handles any of them.
2946 * New command line options
2948 We now accept --silent as an alias for --quiet.
2952 The memory-mapped-malloc library is now licensed under the GNU Library
2953 General Public License.
2955 *** Changes in GDB-4.7:
2957 * Host/native/target split
2959 GDB has had some major internal surgery to untangle the support for
2960 hosts and remote targets. Now, when you configure GDB for a remote
2961 target, it will no longer load in all of the support for debugging
2962 local programs on the host. When fully completed and tested, this will
2963 ensure that arbitrary host/target combinations are possible.
2965 The primary conceptual shift is to separate the non-portable code in
2966 GDB into three categories. Host specific code is required any time GDB
2967 is compiled on that host, regardless of the target. Target specific
2968 code relates to the peculiarities of the target, but can be compiled on
2969 any host. Native specific code is everything else: it can only be
2970 built when the host and target are the same system. Child process
2971 handling and core file support are two common `native' examples.
2973 GDB's use of /proc for controlling Unix child processes is now cleaner.
2974 It has been split out into a single module under the `target_ops' vector,
2975 plus two native-dependent functions for each system that uses /proc.
2977 * New hosts supported
2979 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2980 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2981 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2983 * New targets supported
2985 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2986 68030 and CPU32 m68030-*-*, m68332-*-*
2988 * New native hosts supported
2990 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2991 (386bsd is not well tested yet)
2992 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2994 * New file formats supported
2996 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2997 supports reading of `a.out.adobe' object files, which are an a.out
2998 format extended with minimal information about multiple sections.
3002 `show copying' is the same as the old `info copying'.
3003 `show warranty' is the same as `info warrantee'.
3004 These were renamed for consistency. The old commands continue to work.
3006 `info handle' is a new alias for `info signals'.
3008 You can now define pre-command hooks, which attach arbitrary command
3009 scripts to any command. The commands in the hook will be executed
3010 prior to the user's command. You can also create a hook which will be
3011 executed whenever the program stops. See gdb.texinfo.
3015 We now deal with Cfront style name mangling, and can even extract type
3016 info from mangled symbols. GDB can automatically figure out which
3017 symbol mangling style your C++ compiler uses.
3019 Calling of methods and virtual functions has been improved as well.
3023 The crash that occured when debugging Sun Ansi-C compiled binaries is
3024 fixed. This was due to mishandling of the extra N_SO stabs output
3027 We also finally got Ultrix 4.2 running in house, and fixed core file
3028 support, with help from a dozen people on the net.
3030 John M. Farrell discovered that the reason that single-stepping was so
3031 slow on all of the Mips based platforms (primarily SGI and DEC) was
3032 that we were trying to demangle and lookup a symbol used for internal
3033 purposes on every instruction that was being stepped through. Changing
3034 the name of that symbol so that it couldn't be mistaken for a C++
3035 mangled symbol sped things up a great deal.
3037 Rich Pixley sped up symbol lookups in general by getting much smarter
3038 about when C++ symbol mangling is necessary. This should make symbol
3039 completion (TAB on the command line) much faster. It's not as fast as
3040 we'd like, but it's significantly faster than gdb-4.6.
3044 A new user controllable variable 'call_scratch_address' can
3045 specify the location of a scratch area to be used when GDB
3046 calls a function in the target. This is necessary because the
3047 usual method of putting the scratch area on the stack does not work
3048 in systems that have separate instruction and data spaces.
3050 We integrated changes to support the 29k UDI (Universal Debugger
3051 Interface), but discovered at the last minute that we didn't have all
3052 of the appropriate copyright paperwork. We are working with AMD to
3053 resolve this, and hope to have it available soon.
3057 We have sped up the remote serial line protocol, especially for targets
3058 with lots of registers. It now supports a new `expedited status' ('T')
3059 message which can be used in place of the existing 'S' status message.
3060 This allows the remote stub to send only the registers that GDB
3061 needs to make a quick decision about single-stepping or conditional
3062 breakpoints, eliminating the need to fetch the entire register set for
3063 each instruction being stepped through.
3065 The GDB remote serial protocol now implements a write-through cache for
3066 registers, only re-reading the registers if the target has run.
3068 There is also a new remote serial stub for SPARC processors. You can
3069 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3070 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3071 processor with a serial port.
3075 Configure.in files have become much easier to read and modify. A new
3076 `table driven' format makes it more obvious what configurations are
3077 supported, and what files each one uses.
3081 There is a new opcodes library which will eventually contain all of the
3082 disassembly routines and opcode tables. At present, it only contains
3083 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3084 disassembler (binutils/objdump) to share these routines.
3086 The libiberty library is now copylefted under the GNU Library General
3087 Public License. This allows more liberal use, and was done so libg++
3088 can use it. This makes no difference to GDB, since the Library License
3089 grants all the rights from the General Public License.
3093 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3094 reference to the stabs symbol info used by the debugger. It is (as far
3095 as we know) the only published document on this fascinating topic. We
3096 encourage you to read it, compare it to the stabs information on your
3097 system, and send improvements on the document in general (to
3098 bug-gdb@prep.ai.mit.edu).
3100 And, of course, many bugs have been fixed.
3103 *** Changes in GDB-4.6:
3105 * Better support for C++ function names
3107 GDB now accepts as input the "demangled form" of C++ overloaded function
3108 names and member function names, and can do command completion on such names
3109 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3110 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3111 Make use of command completion, it is your friend.
3113 GDB also now accepts a variety of C++ mangled symbol formats. They are
3114 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3115 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3116 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3117 for the list of formats.
3119 * G++ symbol mangling problem
3121 Recent versions of gcc have a bug in how they emit debugging information for
3122 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3123 directory) can be applied to gcc to fix the problem. Alternatively, if you
3124 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3125 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3126 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3129 * New 'maintenance' command
3131 All of the commands related to hacking GDB internals have been moved out of
3132 the main command set, and now live behind the 'maintenance' command. This
3133 can also be abbreviated as 'mt'. The following changes were made:
3135 dump-me -> maintenance dump-me
3136 info all-breakpoints -> maintenance info breakpoints
3137 printmsyms -> maintenance print msyms
3138 printobjfiles -> maintenance print objfiles
3139 printpsyms -> maintenance print psymbols
3140 printsyms -> maintenance print symbols
3142 The following commands are new:
3144 maintenance demangle Call internal GDB demangler routine to
3145 demangle a C++ link name and prints the result.
3146 maintenance print type Print a type chain for a given symbol
3148 * Change to .gdbinit file processing
3150 We now read the $HOME/.gdbinit file before processing the argv arguments
3151 (e.g. reading symbol files or core files). This allows global parameters to
3152 be set, which will apply during the symbol reading. The ./.gdbinit is still
3153 read after argv processing.
3155 * New hosts supported
3157 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3159 GNU/Linux support i386-unknown-linux or linux
3161 We are also including code to support the HP/PA running BSD and HPUX. This
3162 is almost guaranteed not to work, as we didn't have time to test or build it
3163 for this release. We are including it so that the more adventurous (or
3164 masochistic) of you can play with it. We also had major problems with the
3165 fact that the compiler that we got from HP doesn't support the -g option.
3168 * New targets supported
3170 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3172 * More smarts about finding #include files
3174 GDB now remembers the compilation directory for all include files, and for
3175 all files from which C is generated (like yacc and lex sources). This
3176 greatly improves GDB's ability to find yacc/lex sources, and include files,
3177 especially if you are debugging your program from a directory different from
3178 the one that contains your sources.
3180 We also fixed a bug which caused difficulty with listing and setting
3181 breakpoints in include files which contain C code. (In the past, you had to
3182 try twice in order to list an include file that you hadn't looked at before.)
3184 * Interesting infernals change
3186 GDB now deals with arbitrary numbers of sections, where the symbols for each
3187 section must be relocated relative to that section's landing place in the
3188 target's address space. This work was needed to support ELF with embedded
3189 stabs used by Solaris-2.0.
3191 * Bug fixes (of course!)
3193 There have been loads of fixes for the following things:
3194 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3195 i960, stabs, DOS(GO32), procfs, etc...
3197 See the ChangeLog for details.
3199 *** Changes in GDB-4.5:
3201 * New machines supported (host and target)
3203 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3205 SGI Irix-4.x mips-sgi-irix4 or iris4
3207 * New malloc package
3209 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3210 Mmalloc is capable of handling mutiple heaps of memory. It is also
3211 capable of saving a heap to a file, and then mapping it back in later.
3212 This can be used to greatly speedup the startup of GDB by using a
3213 pre-parsed symbol table which lives in a mmalloc managed heap. For
3214 more details, please read mmalloc/mmalloc.texi.
3218 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3219 'help info proc' for details.
3221 * MIPS ecoff symbol table format
3223 The code that reads MIPS symbol table format is now supported on all hosts.
3224 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3227 * File name changes for MS-DOS
3229 Many files in the config directories have been renamed to make it easier to
3230 support GDB on MS-DOSe systems (which have very restrictive file name
3231 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3232 environment) is close to working but has some remaining problems. Note
3233 that debugging of DOS programs is not supported, due to limitations
3234 in the ``operating system'', but it can be used to host cross-debugging.
3236 * Cross byte order fixes
3238 Many fixes have been made to support cross debugging of Sparc and MIPS
3239 targets from hosts whose byte order differs.
3241 * New -mapped and -readnow options
3243 If memory-mapped files are available on your system through the 'mmap'
3244 system call, you can use the -mapped option on the `file' or
3245 `symbol-file' commands to cause GDB to write the symbols from your
3246 program into a reusable file. If the program you are debugging is
3247 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3248 Future GDB debugging sessions will notice the presence of this file,
3249 and will quickly map in symbol information from it, rather than reading
3250 the symbol table from the executable program. Using the '-mapped'
3251 option in a GDB `file' or `symbol-file' command has the same effect as
3252 starting GDB with the '-mapped' command-line option.
3254 You can cause GDB to read the entire symbol table immediately by using
3255 the '-readnow' option with any of the commands that load symbol table
3256 information (or on the GDB command line). This makes the command
3257 slower, but makes future operations faster.
3259 The -mapped and -readnow options are typically combined in order to
3260 build a `fred.syms' file that contains complete symbol information.
3261 A simple GDB invocation to do nothing but build a `.syms' file for future
3264 gdb -batch -nx -mapped -readnow programname
3266 The `.syms' file is specific to the host machine on which GDB is run.
3267 It holds an exact image of GDB's internal symbol table. It cannot be
3268 shared across multiple host platforms.
3270 * longjmp() handling
3272 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3273 siglongjmp() without losing control. This feature has not yet been ported to
3274 all systems. It currently works on many 386 platforms, all MIPS-based
3275 platforms (SGI, DECstation, etc), and Sun3/4.
3279 Preliminary work has been put in to support the new Solaris OS from Sun. At
3280 this time, it can control and debug processes, but it is not capable of
3285 As always, many many bug fixes. The major areas were with g++, and mipsread.
3286 People using the MIPS-based platforms should experience fewer mysterious
3287 crashes and trashed symbol tables.
3289 *** Changes in GDB-4.4:
3291 * New machines supported (host and target)
3293 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3295 BSD Reno on Vax vax-dec-bsd
3296 Ultrix on Vax vax-dec-ultrix
3298 * New machines supported (target)
3300 AMD 29000 embedded, using EBMON a29k-none-none
3304 GDB continues to improve its handling of C++. `References' work better.
3305 The demangler has also been improved, and now deals with symbols mangled as
3306 per the Annotated C++ Reference Guide.
3308 GDB also now handles `stabs' symbol information embedded in MIPS
3309 `ecoff' symbol tables. Since the ecoff format was not easily
3310 extensible to handle new languages such as C++, this appeared to be a
3311 good way to put C++ debugging info into MIPS binaries. This option
3312 will be supported in the GNU C compiler, version 2, when it is
3315 * New features for SVR4
3317 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3318 shared libraries. Debugging dynamically linked programs should present
3319 only minor differences from debugging statically linked programs.
3321 The `info proc' command will print out information about any process
3322 on an SVR4 system (including the one you are debugging). At the moment,
3323 it prints the address mappings of the process.
3325 If you bring up GDB on another SVR4 system, please send mail to
3326 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3328 * Better dynamic linking support in SunOS
3330 Reading symbols from shared libraries which contain debugging symbols
3331 now works properly. However, there remain issues such as automatic
3332 skipping of `transfer vector' code during function calls, which
3333 make it harder to debug code in a shared library, than to debug the
3334 same code linked statically.
3338 GDB is now using the latest `getopt' routines from the FSF. This
3339 version accepts the -- prefix for options with long names. GDB will
3340 continue to accept the old forms (-option and +option) as well.
3341 Various single letter abbreviations for options have been explicity
3342 added to the option table so that they won't get overshadowed in the
3343 future by other options that begin with the same letter.
3347 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3348 Many assorted bugs have been handled. Many more remain to be handled.
3349 See the various ChangeLog files (primarily in gdb and bfd) for details.
3352 *** Changes in GDB-4.3:
3354 * New machines supported (host and target)
3356 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3357 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3358 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3360 * Almost SCO Unix support
3362 We had hoped to support:
3363 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3364 (except for core file support), but we discovered very late in the release
3365 that it has problems with process groups that render gdb unusable. Sorry
3366 about that. I encourage people to fix it and post the fixes.
3368 * Preliminary ELF and DWARF support
3370 GDB can read ELF object files on System V Release 4, and can handle
3371 debugging records for C, in DWARF format, in ELF files. This support
3372 is preliminary. If you bring up GDB on another SVR4 system, please
3373 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3378 GDB now uses the latest `readline' library. One user-visible change
3379 is that two tabs will list possible command completions, which previously
3380 required typing M-? (meta-question mark, or ESC ?).
3384 The `stepi' bug that many of you noticed has been squashed.
3385 Many bugs in C++ have been handled. Many more remain to be handled.
3386 See the various ChangeLog files (primarily in gdb and bfd) for details.
3388 * State of the MIPS world (in case you wondered):
3390 GDB can understand the symbol tables emitted by the compilers
3391 supplied by most vendors of MIPS-based machines, including DEC. These
3392 symbol tables are in a format that essentially nobody else uses.
3394 Some versions of gcc come with an assembler post-processor called
3395 mips-tfile. This program is required if you want to do source-level
3396 debugging of gcc-compiled programs. I believe FSF does not ship
3397 mips-tfile with gcc version 1, but it will eventually come with gcc
3400 Debugging of g++ output remains a problem. g++ version 1.xx does not
3401 really support it at all. (If you're lucky, you should be able to get
3402 line numbers and stack traces to work, but no parameters or local
3403 variables.) With some work it should be possible to improve the
3406 When gcc version 2 is released, you will have somewhat better luck.
3407 However, even then you will get confusing results for inheritance and
3410 We will eventually provide full debugging of g++ output on
3411 DECstations. This will probably involve some kind of stabs-in-ecoff
3412 encapulation, but the details have not been worked out yet.
3415 *** Changes in GDB-4.2:
3417 * Improved configuration
3419 Only one copy of `configure' exists now, and it is not self-modifying.
3420 Porting BFD is simpler.
3424 The `step' and `next' commands now only stop at the first instruction
3425 of a source line. This prevents the multiple stops that used to occur
3426 in switch statements, for-loops, etc. `Step' continues to stop if a
3427 function that has debugging information is called within the line.
3431 Lots of small bugs fixed. More remain.
3433 * New host supported (not target)
3435 Intel 386 PC clone running Mach i386-none-mach
3438 *** Changes in GDB-4.1:
3440 * Multiple source language support
3442 GDB now has internal scaffolding to handle several source languages.
3443 It determines the type of each source file from its filename extension,
3444 and will switch expression parsing and number formatting to match the
3445 language of the function in the currently selected stack frame.
3446 You can also specifically set the language to be used, with
3447 `set language c' or `set language modula-2'.
3451 GDB now has preliminary support for the GNU Modula-2 compiler,
3452 currently under development at the State University of New York at
3453 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3454 continue through the fall of 1991 and into 1992.
3456 Other Modula-2 compilers are currently not supported, and attempting to
3457 debug programs compiled with them will likely result in an error as the
3458 symbol table is read. Feel free to work on it, though!
3460 There are hooks in GDB for strict type checking and range checking,
3461 in the `Modula-2 philosophy', but they do not currently work.
3465 GDB can now write to executable and core files (e.g. patch
3466 a variable's value). You must turn this switch on, specify
3467 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3468 by assigning a new value to a variable. Modifications take
3471 * Automatic SunOS shared library reading
3473 When you run your program, GDB automatically determines where its
3474 shared libraries (if any) have been loaded, and reads their symbols.
3475 The `share' command is no longer needed. This also works when
3476 examining core files.
3480 You can specify the number of lines that the `list' command shows.
3483 * New machines supported (host and target)
3485 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3486 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3487 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3489 * New hosts supported (not targets)
3491 IBM RT/PC: romp-ibm-aix or rtpc
3493 * New targets supported (not hosts)
3495 AMD 29000 embedded with COFF a29k-none-coff
3496 AMD 29000 embedded with a.out a29k-none-aout
3497 Ultracomputer remote kernel debug a29k-nyu-kern
3499 * New remote interfaces
3505 *** Changes in GDB-4.0:
3509 Wide output is wrapped at good places to make the output more readable.
3511 Gdb now supports cross-debugging from a host machine of one type to a
3512 target machine of another type. Communication with the target system
3513 is over serial lines. The ``target'' command handles connecting to the
3514 remote system; the ``load'' command will download a program into the
3515 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3516 also supports debugging of realtime processes running under VxWorks,
3517 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3518 stub on the target system.
3520 New CPUs supported include the AMD 29000 and Intel 960.
3522 GDB now reads object files and symbol tables via a ``binary file''
3523 library, which allows a single copy of GDB to debug programs of multiple
3524 object file types such as a.out and coff.
3526 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3527 refcard.dvi and refcard.ps are available to format it).
3530 * Control-Variable user interface simplified
3532 All variables that control the operation of the debugger can be set
3533 by the ``set'' command, and displayed by the ``show'' command.
3535 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3536 ``Show prompt'' produces the response:
3537 Gdb's prompt is new-gdb=>.
3539 What follows are the NEW set commands. The command ``help set'' will
3540 print a complete list of old and new set commands. ``help set FOO''
3541 will give a longer description of the variable FOO. ``show'' will show
3542 all of the variable descriptions and their current settings.
3544 confirm on/off: Enables warning questions for operations that are
3545 hard to recover from, e.g. rerunning the program while
3546 it is already running. Default is ON.
3548 editing on/off: Enables EMACS style command line editing
3549 of input. Previous lines can be recalled with
3550 control-P, the current line can be edited with control-B,
3551 you can search for commands with control-R, etc.
3554 history filename NAME: NAME is where the gdb command history
3555 will be stored. The default is .gdb_history,
3556 or the value of the environment variable
3559 history size N: The size, in commands, of the command history. The
3560 default is 256, or the value of the environment variable
3563 history save on/off: If this value is set to ON, the history file will
3564 be saved after exiting gdb. If set to OFF, the
3565 file will not be saved. The default is OFF.
3567 history expansion on/off: If this value is set to ON, then csh-like
3568 history expansion will be performed on
3569 command line input. The default is OFF.
3571 radix N: Sets the default radix for input and output. It can be set
3572 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3573 in the current radix, so "set radix 10" is always a no-op.
3575 height N: This integer value is the number of lines on a page. Default
3576 is 24, the current `stty rows'' setting, or the ``li#''
3577 setting from the termcap entry matching the environment
3580 width N: This integer value is the number of characters on a line.
3581 Default is 80, the current `stty cols'' setting, or the ``co#''
3582 setting from the termcap entry matching the environment
3585 Note: ``set screensize'' is obsolete. Use ``set height'' and
3586 ``set width'' instead.
3588 print address on/off: Print memory addresses in various command displays,
3589 such as stack traces and structure values. Gdb looks
3590 more ``symbolic'' if you turn this off; it looks more
3591 ``machine level'' with it on. Default is ON.
3593 print array on/off: Prettyprint arrays. New convenient format! Default
3596 print demangle on/off: Print C++ symbols in "source" form if on,
3599 print asm-demangle on/off: Same, for assembler level printouts
3602 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3605 * Support for Epoch Environment.
3607 The epoch environment is a version of Emacs v18 with windowing. One
3608 new command, ``inspect'', is identical to ``print'', except that if you
3609 are running in the epoch environment, the value is printed in its own
3613 * Support for Shared Libraries
3615 GDB can now debug programs and core files that use SunOS shared libraries.
3616 Symbols from a shared library cannot be referenced
3617 before the shared library has been linked with the program (this
3618 happens after you type ``run'' and before the function main() is entered).
3619 At any time after this linking (including when examining core files
3620 from dynamically linked programs), gdb reads the symbols from each
3621 shared library when you type the ``sharedlibrary'' command.
3622 It can be abbreviated ``share''.
3624 sharedlibrary REGEXP: Load shared object library symbols for files
3625 matching a unix regular expression. No argument
3626 indicates to load symbols for all shared libraries.
3628 info sharedlibrary: Status of loaded shared libraries.
3633 A watchpoint stops execution of a program whenever the value of an
3634 expression changes. Checking for this slows down execution
3635 tremendously whenever you are in the scope of the expression, but is
3636 quite useful for catching tough ``bit-spreader'' or pointer misuse
3637 problems. Some machines such as the 386 have hardware for doing this
3638 more quickly, and future versions of gdb will use this hardware.
3640 watch EXP: Set a watchpoint (breakpoint) for an expression.
3642 info watchpoints: Information about your watchpoints.
3644 delete N: Deletes watchpoint number N (same as breakpoints).
3645 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3646 enable N: Re-enables watchpoint number N (same as breakpoints).
3649 * C++ multiple inheritance
3651 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3654 * C++ exception handling
3656 Gdb now supports limited C++ exception handling. Besides the existing
3657 ability to breakpoint on an exception handler, gdb can breakpoint on
3658 the raising of an exception (before the stack is peeled back to the
3661 catch FOO: If there is a FOO exception handler in the dynamic scope,
3662 set a breakpoint to catch exceptions which may be raised there.
3663 Multiple exceptions (``catch foo bar baz'') may be caught.
3665 info catch: Lists all exceptions which may be caught in the
3666 current stack frame.
3669 * Minor command changes
3671 The command ``call func (arg, arg, ...)'' now acts like the print
3672 command, except it does not print or save a value if the function's result
3673 is void. This is similar to dbx usage.
3675 The ``up'' and ``down'' commands now always print the frame they end up
3676 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3677 frames without printing.
3679 * New directory command
3681 'dir' now adds directories to the FRONT of the source search path.
3682 The path starts off empty. Source files that contain debug information
3683 about the directory in which they were compiled can be found even
3684 with an empty path; Sun CC and GCC include this information. If GDB can't
3685 find your source file in the current directory, type "dir .".
3687 * Configuring GDB for compilation
3689 For normal use, type ``./configure host''. See README or gdb.texinfo
3692 GDB now handles cross debugging. If you are remotely debugging between
3693 two different machines, type ``./configure host -target=targ''.
3694 Host is the machine where GDB will run; targ is the machine
3695 where the program that you are debugging will run.