1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * Tracepoints may now be conditional. The syntax is as for
7 breakpoints; either an "if" clause appended to the "trace" command,
8 or the "condition" command is available. GDB sends the condition to
9 the target for evaluation using the same bytecode format as is used
10 for tracepoint actions.
12 * "disassemble" command with a /r modifier, print the raw instructions
13 in hex as well as in symbolic form."
15 * Process record and replay
17 In a architecture environment that supports ``process record and
18 replay'', ``process record and replay'' target can record a log of
19 the process execution, and replay it with both forward and reverse
22 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
23 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
24 set execution-direction {forward|reverse}, for targets that support
27 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
28 feature is available with a native GDB running on kernel version
31 * GDB now has support for multi-byte and wide character sets on the
32 target. Strings whose character type is wchar_t, char16_t, or
33 char32_t are now correctly printed. GDB supports wide- and unicode-
34 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
35 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
36 `printf'. This feature requires iconv to work properly; if your
37 system does not have a working iconv, GDB can use GNU libiconv. See
38 the installation instructions for more information.
40 * GDB now supports automatic retrieval of shared library files from
41 remote targets. To use this feature, specify a system root that begins
42 with the `remote:' prefix, either via the `set sysroot' command or via
43 the `--with-sysroot' configure-time option.
45 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
46 now complete on file names.
48 * When completing in expressions, gdb will attempt to limit
49 completions to allowable structure or union fields, where appropriate.
50 For instance, consider:
52 # struct example { int f1; double f2; };
53 # struct example variable;
56 If the user types TAB at the end of this command line, the available
57 completions will be "f1" and "f2".
59 * Inlined functions are now supported. They show up in backtraces, and
60 the "step", "next", and "finish" commands handle them automatically.
62 * GDB now supports the token-splicing (##) and stringification (#)
63 operators when expanding macros. It also supports variable-arity
66 * GDB now supports inspecting extra signal information, exported by
67 the new $_siginfo convenience variable. The feature is currently
68 implemented on linux ARM, i386 and amd64.
70 * GDB can now display the VFP floating point registers and NEON vector
71 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
72 can provide these registers (requires Linux 2.6.30 or later). Remote
73 and simulator targets may also provide them.
78 Search memory for a sequence of bytes.
81 Turn off `+'/`-' protocol acknowledgments to permit more efficient
82 operation over reliable transport links. Use of this packet is
83 controlled by the `set remote noack-packet' command.
86 Kill the process with the specified process ID. Use this in preference
87 to `k' when multiprocess protocol extensions are supported.
90 Obtains additional operating system information
94 Read or write additional signal information.
96 * Removed remote protocol undocumented extension
98 An undocumented extension to the remote protocol's `S' stop reply
99 packet that permited the stub to pass a process id was removed.
100 Remote servers should use the `T' stop reply packet instead.
102 * The "disassemble" command now supports an optional /m modifier to print mixed
105 * GDB now supports multiple function calling conventions according to the
106 DWARF-2 DW_AT_calling_convention function attribute.
108 * The SH target utilizes the aforementioned change to distinguish between gcc
109 and Renesas calling convention. It also adds the new CLI commands
110 `set/show sh calling-convention'.
112 * GDB can now read compressed debug sections, as produced by GNU gold
113 with the --compress-debug-sections=zlib flag.
115 * 64-bit core files are now supported on AIX.
117 * Thread switching is now supported on Tru64.
119 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
120 which will be allocated using malloc later in program execution.
122 * The qXfer:libraries:read remote procotol packet now allows passing a
123 list of section offsets.
125 * On GNU/Linux, GDB can now attach to stopped processes. Several race
126 conditions handling signals delivered during attach or thread creation
127 have also been fixed.
129 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
130 From the user's standpoint, all unqualified instances of True and False
131 are treated as the standard definitions, regardless of context.
133 * GDB now parses C++ symbol and type names more flexibly. For
136 template<typename T> class C { };
139 GDB will now correctly handle all of:
141 ptype C<char const *>
143 ptype C<const char *>
146 * New features in the GDB remote stub, gdbserver
148 - The "--wrapper" command-line argument tells gdbserver to use a
149 wrapper program to launch programs for debugging.
151 - On PowerPC and S/390 targets, it is now possible to use a single
152 gdbserver executable to debug both 32-bit and 64-bit programs.
153 (This requires gdbserver itself to be built as a 64-bit executable.)
155 - gdbserver uses the new noack protocol mode for TCP connections to
156 reduce communications latency, if also supported and enabled in GDB.
158 - Support for the sparc64-linux-gnu target is now included in
161 - The amd64-linux build of gdbserver now supports debugging both
162 32-bit and 64-bit programs.
164 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
165 now support hardware watchpoints, and will use them automatically
170 GDB now has support for scripting using Python. Whether this is
171 available is determined at configure time.
173 New GDB commands can now be written in Python.
175 * Ada tasking support
177 Ada tasks can now be inspected in GDB. The following commands have
181 Print the list of Ada tasks.
183 Print detailed information about task number N.
185 Print the task number of the current task.
187 Switch the context of debugging to task number N.
189 * Support for user-defined prefixed commands. The "define" command can
190 add new commands to existing prefixes, e.g. "target".
192 * Multi-inferior, multi-process debugging.
194 GDB now has generalized support for multi-inferior debugging. See
195 "Debugging Multiple Inferiors" in the manual for more information.
196 Although availability still depends on target support, the command
197 set is more uniform now. The GNU/Linux specific multi-forks support
198 has been migrated to this new framework. This implied some user
199 visible changes; see "New commands" and also "Removed commands"
202 * Target descriptions can now describe the target OS ABI. See the
203 "Target Description Format" section in the user manual for more
206 * Target descriptions can now describe "compatible" architectures
207 to indicate that the target can execute applications for a different
208 architecture in addition to those for the main target architecture.
209 See the "Target Description Format" section in the user manual for
212 * Multi-architecture debugging.
214 GDB now includes general supports for debugging applications on
215 hybrid systems that use more than one single processor architecture
216 at the same time. Each such hybrid architecture still requires
217 specific support to be added. The only hybrid architecture supported
218 in this version of GDB is the Cell Broadband Engine.
220 * GDB now supports integrated debugging of Cell/B.E. applications that
221 use both the PPU and SPU architectures. To enable support for hybrid
222 Cell/B.E. debugging, you need to configure GDB to support both the
223 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
224 --enable-targets configure option.
226 * New commands (for set/show, see "New options" below)
228 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
230 Search memory for a sequence of bytes.
232 maint set python print-stack
233 maint show python print-stack
234 Show a stack trace when an error is encountered in a Python script.
237 Invoke CODE by passing it to the Python interpreter.
242 These allow macros to be defined, undefined, and listed
246 Show operating system information about processes.
249 List the inferiors currently under GDB's control.
252 Switch focus to inferior number NUM.
255 Detach from inferior number NUM.
258 Kill inferior number NUM.
263 show spu stop-on-load
264 Control whether to stop for new SPE threads during Cell/B.E. debugging.
266 set spu auto-flush-cache
267 show spu auto-flush-cache
268 Control whether to automatically flush the software-managed cache
269 during Cell/B.E. debugging.
271 set sh calling-convention
272 show sh calling-convention
273 Control the calling convention used when calling SH target functions.
275 set print symbol-loading
276 show print symbol-loading
277 Control printing of symbol loading messages.
281 Control display of timestamps with GDB debugging output.
283 set disassemble-next-line
284 show disassemble-next-line
285 Control display of disassembled source lines or instructions when
288 set remote noack-packet
289 show remote noack-packet
290 Set/show the use of remote protocol QStartNoAckMode packet. See above
291 under "New remote packets."
293 set remote query-attached-packet
294 show remote query-attached-packet
295 Control use of remote protocol `qAttached' (query-attached) packet.
297 set remote read-siginfo-object
298 show remote read-siginfo-object
299 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
302 set remote write-siginfo-object
303 show remote write-siginfo-object
304 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
307 set displaced-stepping
308 show displaced-stepping
309 Control displaced stepping mode. Displaced stepping is a way to
310 single-step over breakpoints without removing them from the debuggee.
311 Also known as "out-of-line single-stepping".
315 Control display of debugging info for displaced stepping.
317 maint set internal-error
318 maint show internal-error
319 Control what GDB does when an internal error is detected.
321 maint set internal-warning
322 maint show internal-warning
323 Control what GDB does when an internal warning is detected.
328 Use a wrapper program to launch programs for debugging.
330 set multiple-symbols (all|ask|cancel)
331 show multiple-symbols
332 The value of this variable can be changed to adjust the debugger behavior
333 when an expression or a breakpoint location contains an ambiguous symbol
334 name (an overloaded function name, for instance).
336 set breakpoint always-inserted
337 show breakpoint always-inserted
338 Keep breakpoints always inserted in the target, as opposed to inserting
339 them when resuming the target, and removing them when the target stops.
340 This option can improve debugger performance on slow remote targets.
342 set arm fallback-mode (arm|thumb|auto)
343 show arm fallback-mode
344 set arm force-mode (arm|thumb|auto)
346 These commands control how ARM GDB determines whether instructions
347 are ARM or Thumb. The default for both settings is auto, which uses
348 the current CPSR value for instructions without symbols; previous
349 versions of GDB behaved as if "set arm fallback-mode arm".
351 set disable-randomization
352 show disable-randomization
353 Standalone programs run with the virtual address space randomization enabled
354 by default on some platforms. This option keeps the addresses stable across
355 multiple debugging sessions.
359 Control whether other threads are stopped or not when some thread hits
364 Requests that asynchronous execution is enabled in the target, if available.
365 In this case, it's possible to resume target in the background, and interact
366 with GDB while the target is running. "show target-async" displays the
367 current state of asynchronous execution of the target.
369 set target-wide-charset
370 show target-wide-charset
371 The target-wide-charset is the name of the character set that GDB
372 uses when printing characters whose type is wchar_t.
374 set tcp auto-retry (on|off)
376 set tcp connect-timeout
377 show tcp connect-timeout
378 These commands allow GDB to retry failed TCP connections to a remote stub
379 with a specified timeout period; this is useful if the stub is launched
380 in parallel with GDB but may not be ready to accept connections immediately.
382 set libthread-db-search-path
383 show libthread-db-search-path
384 Control list of directories which GDB will search for appropriate
387 set schedule-multiple (on|off)
388 show schedule-multiple
389 Allow GDB to resume all threads of all processes or only threads of
395 For program forks, this is replaced by the new more generic `info
396 inferiors' command. To list checkpoints, you can still use the
397 `info checkpoints' command, which was an alias for the `info forks'
401 Replaced by the new `inferior' command. To switch between
402 checkpoints, you can still use the `restart' command, which was an
403 alias for the `fork' command.
406 This is removed, since some targets don't have a notion of
407 processes. To switch between processes, you can still use the
408 `inferior' command using GDB's own inferior number.
411 For program forks, this is replaced by the new more generic `kill
412 inferior' command. To delete a checkpoint, you can still use the
413 `delete checkpoint' command, which was an alias for the `delete
417 For program forks, this is replaced by the new more generic `detach
418 inferior' command. To detach a checkpoint, you can still use the
419 `detach checkpoint' command, which was an alias for the `detach
422 * New native configurations
424 x86/x86_64 Darwin i[34567]86-*-darwin*
426 x86_64 MinGW x86_64-*-mingw*
430 Lattice Mico32 lm32-*
431 x86 DICOS i[34567]86-*-dicos*
432 x86_64 DICOS x86_64-*-dicos*
434 * The GDB remote stub, gdbserver, now supports x86 Windows CE
435 (mingw32ce) debugging.
441 These commands were actually not implemented on any target.
443 *** Changes in GDB 6.8
445 * New native configurations
447 NetBSD/hppa hppa*-*netbsd*
448 Xtensa GNU/Linux xtensa*-*-linux*
452 NetBSD/hppa hppa*-*-netbsd*
453 Xtensa GNU/Lunux xtensa*-*-linux*
455 * Change in command line behavior -- corefiles vs. process ids.
457 When the '-p NUMBER' or '--pid NUMBER' options are used, and
458 attaching to process NUMBER fails, GDB no longer attempts to open a
459 core file named NUMBER. Attaching to a program using the -c option
460 is no longer supported. Instead, use the '-p' or '--pid' options.
462 * GDB can now be built as a native debugger for debugging Windows x86
463 (mingw32) Portable Executable (PE) programs.
465 * Pending breakpoints no longer change their number when their address
468 * GDB now supports breakpoints with multiple locations,
469 including breakpoints on C++ constructors, inside C++ templates,
470 and in inlined functions.
472 * GDB's ability to debug optimized code has been improved. GDB more
473 accurately identifies function bodies and lexical blocks that occupy
474 more than one contiguous range of addresses.
476 * Target descriptions can now describe registers for PowerPC.
478 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
479 registers on PowerPC targets.
481 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
482 targets even when the libthread_db library is not available.
484 * The GDB remote stub, gdbserver, now supports the new file transfer
485 commands (remote put, remote get, and remote delete).
487 * The GDB remote stub, gdbserver, now supports run and attach in
488 extended-remote mode.
490 * hppa*64*-*-hpux11* target broken
491 The debugger is unable to start a program and fails with the following
492 error: "Error trying to get information about dynamic linker".
493 The gdb-6.7 release is also affected.
495 * GDB now supports the --enable-targets= configure option to allow
496 building a single GDB executable that supports multiple remote
497 target architectures.
499 * GDB now supports debugging C and C++ programs which use the
500 Decimal Floating Point extension. In addition, the PowerPC target
501 now has a set of pseudo-registers to inspect decimal float values
502 stored in two consecutive float registers.
504 * The -break-insert MI command can optionally create pending
507 * Improved support for debugging Ada
508 Many improvements to the Ada language support have been made. These
510 - Better support for Ada2005 interface types
511 - Improved handling of arrays and slices in general
512 - Better support for Taft-amendment types
513 - The '{type} ADDRESS' expression is now allowed on the left hand-side
515 - Improved command completion in Ada
518 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
523 set print frame-arguments (all|scalars|none)
524 show print frame-arguments
525 The value of this variable can be changed to control which argument
526 values should be printed by the debugger when displaying a frame.
531 Transfer files to and from a remote target, and delete remote files.
538 Transfer files to and from a remote target, and delete remote files.
547 Open, close, read, write, and delete files on the remote system.
550 Attach to an existing process on the remote system, in extended-remote
554 Run a new process on the remote system, in extended-remote mode.
556 *** Changes in GDB 6.7
558 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
559 bfd, libiberty and opcodes, as revealed by static analysis donated by
560 Coverity, Inc. (http://scan.coverity.com).
562 * When looking up multiply-defined global symbols, GDB will now prefer the
563 symbol definition in the current shared library if it was built using the
564 -Bsymbolic linker option.
566 * When the Text User Interface (TUI) is not configured, GDB will now
567 recognize the -tui command-line option and print a message that the TUI
570 * The GDB remote stub, gdbserver, now has lower overhead for high
571 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
573 * GDB for MIPS targets now autodetects whether a remote target provides
574 32-bit or 64-bit register values.
576 * Support for C++ member pointers has been improved.
578 * GDB now understands XML target descriptions, which specify the
579 target's overall architecture. GDB can read a description from
580 a local file or over the remote serial protocol.
582 * Vectors of single-byte data use a new integer type which is not
583 automatically displayed as character or string data.
585 * The /s format now works with the print command. It displays
586 arrays of single-byte integers and pointers to single-byte integers
589 * Target descriptions can now describe target-specific registers,
590 for architectures which have implemented the support (currently
591 only ARM, M68K, and MIPS).
593 * GDB and the GDB remote stub, gdbserver, now support the XScale
596 * The GDB remote stub, gdbserver, has been updated to support
597 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
598 has been rewritten to use the standard GDB remote protocol.
600 * GDB can now step into C++ functions which are called through thunks.
602 * GDB for the Cell/B.E. SPU now supports overlay debugging.
604 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
605 layout. It also supports a TextSeg= and DataSeg= response when only
606 segment base addresses (rather than offsets) are available.
608 * The /i format now outputs any trailing branch delay slot instructions
609 immediately following the last instruction within the count specified.
611 * The GDB remote protocol "T" stop reply packet now supports a
612 "library" response. Combined with the new "qXfer:libraries:read"
613 packet, this response allows GDB to debug shared libraries on targets
614 where the operating system manages the list of loaded libraries (e.g.
615 Windows and SymbianOS).
617 * The GDB remote stub, gdbserver, now supports dynamic link libraries
618 (DLLs) on Windows and Windows CE targets.
620 * GDB now supports a faster verification that a .debug file matches its binary
621 according to its build-id signature, if the signature is present.
627 Enable or disable hardware flow control (RTS/CTS) on the serial port
628 when debugging using remote targets.
630 set mem inaccessible-by-default
631 show mem inaccessible-by-default
632 If the target supplies a memory map, for instance via the remote
633 protocol's "qXfer:memory-map:read" packet, setting this variable
634 prevents GDB from accessing memory outside the memory map. This
635 is useful for targets with memory mapped registers or which react
636 badly to accesses of unmapped address space.
638 set breakpoint auto-hw
639 show breakpoint auto-hw
640 If the target supplies a memory map, for instance via the remote
641 protocol's "qXfer:memory-map:read" packet, setting this variable
642 lets GDB use hardware breakpoints automatically for memory regions
643 where it can not use software breakpoints. This covers both the
644 "break" command and internal breakpoints used for other commands
645 including "next" and "finish".
648 catch exception unhandled
649 Stop the program execution when Ada exceptions are raised.
652 Stop the program execution when an Ada assertion failed.
656 Set an alternate system root for target files. This is a more
657 general version of "set solib-absolute-prefix", which is now
658 an alias to "set sysroot".
661 Provide extended SPU facility status information. This set of
662 commands is available only when debugging the Cell/B.E. SPU
665 * New native configurations
667 OpenBSD/sh sh*-*openbsd*
672 Use the specified local file as an XML target description, and do
673 not query the target for its built-in description.
677 OpenBSD/sh sh*-*-openbsd*
678 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
679 Toshiba Media Processor mep-elf
684 Ignore the specified signals; pass them directly to the debugged program
685 without stopping other threads or reporting them to GDB.
688 Read an XML target description from the target, which describes its
693 Read or write contents of an spufs file on the target system. These
694 packets are available only on the Cell/B.E. SPU architecture.
696 qXfer:libraries:read:
697 Report the loaded shared libraries. Combined with new "T" packet
698 response, this packet allows GDB to debug shared libraries on
699 targets where the operating system manages the list of loaded
700 libraries (e.g. Windows and SymbianOS).
704 Support for these obsolete configurations has been removed.
713 i[34567]86-*-netware*
714 i[34567]86-*-sco3.2v5*
715 i[34567]86-*-sco3.2v4*
717 i[34567]86-*-sysv4.2*
720 i[34567]86-*-unixware2*
721 i[34567]86-*-unixware*
730 * Other removed features
737 Various m68k-only ROM monitors.
744 Various Renesas ROM monitors and debugging interfaces for SH and
749 Support for a Macraigor serial interface to on-chip debugging.
750 GDB does not directly support the newer parallel or USB
755 A debug information format. The predecessor to DWARF 2 and
756 DWARF 3, which are still supported.
758 Support for the HP aCC compiler on HP-UX/PA-RISC
760 SOM-encapsulated symbolic debugging information, automatic
761 invocation of pxdb, and the aCC custom C++ ABI. This does not
762 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
763 with aCC can still be debugged on an assembly level.
767 A MIPS-specific format used to describe stack frame layout
768 in debugging information.
772 GDB could work with an older version of Guile to debug
773 the interpreter and Scheme programs running in it.
775 set mips stack-arg-size
776 set mips saved-gpreg-size
778 Use "set mips abi" to control parameter passing for MIPS.
780 *** Changes in GDB 6.6
785 Cell Broadband Engine SPU spu-elf
787 * GDB can now be configured as a cross-debugger targeting native Windows
788 (mingw32) or Cygwin. It can communicate with a remote debugging stub
789 running on a Windows system over TCP/IP to debug Windows programs.
791 * The GDB remote stub, gdbserver, has been updated to support Windows and
792 Cygwin debugging. Both single-threaded and multi-threaded programs are
795 * The "set trust-readonly-sections" command works again. This command was
796 broken in GDB 6.3, 6.4, and 6.5.
798 * The "load" command now supports writing to flash memory, if the remote
799 stub provides the required support.
801 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
802 longer requires symbolic debug information (e.g. DWARF-2).
807 unset substitute-path
809 Manage a list of substitution rules that GDB uses to rewrite the name
810 of the directories where the sources are located. This can be useful
811 for instance when the sources were moved to a different location
812 between compilation and debugging.
816 Print each CLI command as it is executed. Each command is prefixed with
817 a number of `+' symbols representing the nesting depth.
818 The source command now has a `-v' option to enable the same feature.
822 The ARM Demon monitor support (RDP protocol, "target rdp").
824 Kernel Object Display, an embedded debugging feature which only worked with
825 an obsolete version of Cisco IOS.
827 The 'set download-write-size' and 'show download-write-size' commands.
832 Tell a stub about GDB client features, and request remote target features.
833 The first feature implemented is PacketSize, which allows the target to
834 specify the size of packets it can handle - to minimize the number of
835 packets required and improve performance when connected to a remote
839 Fetch an OS auxilliary vector from the remote stub. This packet is a
840 more efficient replacement for qPart:auxv:read.
842 qXfer:memory-map:read:
843 Fetch a memory map from the remote stub, including information about
844 RAM, ROM, and flash memory devices.
849 Erase and program a flash memory device.
851 * Removed remote packets
854 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
855 used it, and only gdbserver implemented it.
857 *** Changes in GDB 6.5
861 Renesas M32C/M16C m32c-elf
863 Morpho Technologies ms1 ms1-elf
867 init-if-undefined Initialize a convenience variable, but
868 only if it doesn't already have a value.
870 The following commands are presently only implemented for native GNU/Linux:
872 checkpoint Save a snapshot of the program state.
874 restart <n> Return the program state to a
875 previously saved state.
877 info checkpoints List currently saved checkpoints.
879 delete-checkpoint <n> Delete a previously saved checkpoint.
881 set|show detach-on-fork Tell gdb whether to detach from a newly
882 forked process, or to keep debugging it.
884 info forks List forks of the user program that
885 are available to be debugged.
887 fork <n> Switch to debugging one of several
888 forks of the user program that are
889 available to be debugged.
891 delete-fork <n> Delete a fork from the list of forks
892 that are available to be debugged (and
893 kill the forked process).
895 detach-fork <n> Delete a fork from the list of forks
896 that are available to be debugged (and
897 allow the process to continue).
901 Morpho Technologies ms2 ms1-elf
903 * Improved Windows host support
905 GDB now builds as a cross debugger hosted on i686-mingw32, including
906 native console support, and remote communications using either
907 network sockets or serial ports.
909 * Improved Modula-2 language support
911 GDB can now print most types in the Modula-2 syntax. This includes:
912 basic types, set types, record types, enumerated types, range types,
913 pointer types and ARRAY types. Procedure var parameters are correctly
914 printed and hexadecimal addresses and character constants are also
915 written in the Modula-2 syntax. Best results can be obtained by using
916 GNU Modula-2 together with the -gdwarf-2 command line option.
920 The ARM rdi-share module.
922 The Netware NLM debug server.
924 *** Changes in GDB 6.4
926 * New native configurations
928 OpenBSD/arm arm*-*-openbsd*
929 OpenBSD/mips64 mips64-*-openbsd*
933 Morpho Technologies ms1 ms1-elf
935 * New command line options
937 --batch-silent As for --batch, but totally silent.
938 --return-child-result The debugger will exist with the same value
939 the child (debugged) program exited with.
940 --eval-command COMMAND, -ex COMMAND
941 Execute a single GDB CLI command. This may be
942 specified multiple times and in conjunction
943 with the --command (-x) option.
945 * Deprecated commands removed
947 The following commands, that were deprecated in 2000, have been
951 set|show arm disassembly-flavor set|show arm disassembler
952 othernames set arm disassembler
953 set|show remotedebug set|show debug remote
954 set|show archdebug set|show debug arch
955 set|show eventdebug set|show debug event
958 * New BSD user-level threads support
960 It is now possible to debug programs using the user-level threads
961 library on OpenBSD and FreeBSD. Currently supported (target)
964 FreeBSD/amd64 x86_64-*-freebsd*
965 FreeBSD/i386 i386-*-freebsd*
966 OpenBSD/i386 i386-*-openbsd*
968 Note that the new kernel threads libraries introduced in FreeBSD 5.x
969 are not yet supported.
971 * New support for Matsushita MN10300 w/sim added
972 (Work in progress). mn10300-elf.
974 * REMOVED configurations and files
976 VxWorks and the XDR protocol *-*-vxworks
977 Motorola MCORE mcore-*-*
978 National Semiconductor NS32000 ns32k-*-*
980 * New "set print array-indexes" command
982 After turning this setting "on", GDB prints the index of each element
983 when displaying arrays. The default is "off" to preserve the previous
986 * VAX floating point support
988 GDB now supports the not-quite-ieee VAX F and D floating point formats.
990 * User-defined command support
992 In addition to using $arg0..$arg9 for argument passing, it is now possible
993 to use $argc to determine now many arguments have been passed. See the
994 section on user-defined commands in the user manual for more information.
996 *** Changes in GDB 6.3:
998 * New command line option
1000 GDB now accepts -l followed by a number to set the timeout for remote
1003 * GDB works with GCC -feliminate-dwarf2-dups
1005 GDB now supports a more compact representation of DWARF-2 debug
1006 information using DW_FORM_ref_addr references. These are produced
1007 by GCC with the option -feliminate-dwarf2-dups and also by some
1008 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1009 to use -feliminate-dwarf2-dups.
1011 * Internationalization
1013 When supported by the host system, GDB will be built with
1014 internationalization (libintl). The task of marking up the sources is
1015 continued, we're looking forward to our first translation.
1019 Initial support for debugging programs compiled with the GNAT
1020 implementation of the Ada programming language has been integrated
1021 into GDB. In this release, support is limited to expression evaluation.
1023 * New native configurations
1025 GNU/Linux/m32r m32r-*-linux-gnu
1029 GDB's remote protocol now includes support for the 'p' packet. This
1030 packet is used to fetch individual registers from a remote inferior.
1032 * END-OF-LIFE registers[] compatibility module
1034 GDB's internal register infrastructure has been completely rewritten.
1035 The new infrastructure making possible the implementation of key new
1036 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1039 GDB 6.3 will be the last release to include the the registers[]
1040 compatibility module that allowed out-of-date configurations to
1041 continue to work. This change directly impacts the following
1051 powerpc bdm protocol
1053 Unless there is activity to revive these configurations, they will be
1054 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1056 * OBSOLETE configurations and files
1058 Configurations that have been declared obsolete in this release have
1059 been commented out. Unless there is activity to revive these
1060 configurations, the next release of GDB will have their sources
1061 permanently REMOVED.
1070 *** Changes in GDB 6.2.1:
1072 * MIPS `break main; run' gave an heuristic-fence-post warning
1074 When attempting to run even a simple program, a warning about
1075 heuristic-fence-post being hit would be reported. This problem has
1078 * MIPS IRIX 'long double' crashed GDB
1080 When examining a long double variable, GDB would get a segmentation
1081 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1082 IRIX long double values).
1086 A bug in the VAX stack code was causing problems with the "next"
1087 command. This problem has been fixed.
1089 *** Changes in GDB 6.2:
1091 * Fix for ``many threads''
1093 On GNU/Linux systems that use the NPTL threads library, a program
1094 rapidly creating and deleting threads would confuse GDB leading to the
1097 ptrace: No such process.
1098 thread_db_get_info: cannot get thread info: generic error
1100 This problem has been fixed.
1102 * "-async" and "-noasync" options removed.
1104 Support for the broken "-noasync" option has been removed (it caused
1107 * New ``start'' command.
1109 This command runs the program until the begining of the main procedure.
1111 * New BSD Kernel Data Access Library (libkvm) interface
1113 Using ``target kvm'' it is now possible to debug kernel core dumps and
1114 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1115 platforms. Currently supported (native-only) configurations are:
1117 FreeBSD/amd64 x86_64-*-freebsd*
1118 FreeBSD/i386 i?86-*-freebsd*
1119 NetBSD/i386 i?86-*-netbsd*
1120 NetBSD/m68k m68*-*-netbsd*
1121 NetBSD/sparc sparc-*-netbsd*
1122 OpenBSD/amd64 x86_64-*-openbsd*
1123 OpenBSD/i386 i?86-*-openbsd*
1124 OpenBSD/m68k m68*-openbsd*
1125 OpenBSD/sparc sparc-*-openbsd*
1127 * Signal trampoline code overhauled
1129 Many generic problems with GDB's signal handling code have been fixed.
1130 These include: backtraces through non-contiguous stacks; recognition
1131 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1132 call; backtrace through a signal trampoline; step into and out of
1133 signal handlers; and single-stepping in the signal trampoline.
1135 Please note that kernel bugs are a limiting factor here. These
1136 features have been shown to work on an s390 GNU/Linux system that
1137 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1139 * Cygwin support for DWARF 2 added.
1141 * New native configurations
1143 GNU/Linux/hppa hppa*-*-linux*
1144 OpenBSD/hppa hppa*-*-openbsd*
1145 OpenBSD/m68k m68*-*-openbsd*
1146 OpenBSD/m88k m88*-*-openbsd*
1147 OpenBSD/powerpc powerpc-*-openbsd*
1148 NetBSD/vax vax-*-netbsd*
1149 OpenBSD/vax vax-*-openbsd*
1151 * END-OF-LIFE frame compatibility module
1153 GDB's internal frame infrastructure has been completely rewritten.
1154 The new infrastructure making it possible to support key new features
1155 including DWARF 2 Call Frame Information. To aid in the task of
1156 migrating old configurations to this new infrastructure, a
1157 compatibility module, that allowed old configurations to continue to
1158 work, was also included.
1160 GDB 6.2 will be the last release to include this frame compatibility
1161 module. This change directly impacts the following configurations:
1171 Unless there is activity to revive these configurations, they will be
1172 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1174 * REMOVED configurations and files
1176 Sun 3, running SunOS 3 m68*-*-sunos3*
1177 Sun 3, running SunOS 4 m68*-*-sunos4*
1178 Sun 2, running SunOS 3 m68000-*-sunos3*
1179 Sun 2, running SunOS 4 m68000-*-sunos4*
1180 Motorola 680x0 running LynxOS m68*-*-lynxos*
1181 AT&T 3b1/Unix pc m68*-att-*
1182 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1183 decstation mips-dec-* mips-little-*
1184 riscos mips-*-riscos* mips-*-sysv*
1185 sonymips mips-sony-*
1186 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1188 *** Changes in GDB 6.1.1:
1190 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1192 The TUI (Text-mode User Interface) is now built as part of a default
1193 GDB configuration. It is enabled by either selecting the TUI with the
1194 command line option "-i=tui" or by running the separate "gdbtui"
1195 program. For more information on the TUI, see the manual "Debugging
1198 * Pending breakpoint support (also included in GDB 6.1)
1200 Support has been added to allow you to specify breakpoints in shared
1201 libraries that have not yet been loaded. If a breakpoint location
1202 cannot be found, and the "breakpoint pending" option is set to auto,
1203 GDB queries you if you wish to make the breakpoint pending on a future
1204 shared-library load. If and when GDB resolves the breakpoint symbol,
1205 the pending breakpoint is removed as one or more regular breakpoints
1208 Pending breakpoints are very useful for GCJ Java debugging.
1210 * Fixed ISO-C build problems
1212 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1213 non ISO-C code that stopped them being built using a more strict ISO-C
1214 compiler (e.g., IBM's C compiler).
1216 * Fixed build problem on IRIX 5
1218 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1219 wasn't able to compile compile on an IRIX 5 system.
1221 * Added execute permission to gdb/gdbserver/configure
1223 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1224 permission. This bug would cause configure to fail on a number of
1225 systems (Solaris, IRIX). Ref: server/519.
1227 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1229 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1230 has been updated to use constant array sizes.
1232 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1234 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1235 its generated DWARF Call Frame Info. This encoding was causing GDB to
1236 panic, that panic has been fixed. Ref: gdb/1628.
1238 * Fixed a problem when examining parameters in shared library code.
1240 When examining parameters in optimized shared library code generated
1241 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1242 not available''. GDB now correctly displays the variable's value.
1244 *** Changes in GDB 6.1:
1246 * Removed --with-mmalloc
1248 Support for the mmalloc memory manager has been removed, as it
1249 conflicted with the internal gdb byte cache.
1251 * Changes in AMD64 configurations
1253 The AMD64 target now includes the %cs and %ss registers. As a result
1254 the AMD64 remote protocol has changed; this affects the floating-point
1255 and SSE registers. If you rely on those registers for your debugging,
1256 you should upgrade gdbserver on the remote side.
1258 * Revised SPARC target
1260 The SPARC target has been completely revised, incorporating the
1261 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1262 support for LynxOS and SunOS 4 has been dropped. Calling functions
1263 from within GDB on operating systems with a non-executable stack
1264 (Solaris, OpenBSD) now works.
1268 GDB has a new C++ demangler which does a better job on the mangled
1269 names generated by current versions of g++. It also runs faster, so
1270 with this and other changes gdb should now start faster on large C++
1273 * DWARF 2 Location Expressions
1275 GDB support for location expressions has been extended to support function
1276 arguments and frame bases. Older versions of GDB could crash when they
1279 * C++ nested types and namespaces
1281 GDB's support for nested types and namespaces in C++ has been
1282 improved, especially if you use the DWARF 2 debugging format. (This
1283 is the default for recent versions of GCC on most platforms.)
1284 Specifically, if you have a class "Inner" defined within a class or
1285 namespace "Outer", then GDB realizes that the class's name is
1286 "Outer::Inner", not simply "Inner". This should greatly reduce the
1287 frequency of complaints about not finding RTTI symbols. In addition,
1288 if you are stopped at inside of a function defined within a namespace,
1289 GDB modifies its name lookup accordingly.
1291 * New native configurations
1293 NetBSD/amd64 x86_64-*-netbsd*
1294 OpenBSD/amd64 x86_64-*-openbsd*
1295 OpenBSD/alpha alpha*-*-openbsd*
1296 OpenBSD/sparc sparc-*-openbsd*
1297 OpenBSD/sparc64 sparc64-*-openbsd*
1299 * New debugging protocols
1301 M32R with SDI protocol m32r-*-elf*
1303 * "set prompt-escape-char" command deleted.
1305 The command "set prompt-escape-char" has been deleted. This command,
1306 and its very obscure effet on GDB's prompt, was never documented,
1307 tested, nor mentioned in the NEWS file.
1309 * OBSOLETE configurations and files
1311 Configurations that have been declared obsolete in this release have
1312 been commented out. Unless there is activity to revive these
1313 configurations, the next release of GDB will have their sources
1314 permanently REMOVED.
1316 Sun 3, running SunOS 3 m68*-*-sunos3*
1317 Sun 3, running SunOS 4 m68*-*-sunos4*
1318 Sun 2, running SunOS 3 m68000-*-sunos3*
1319 Sun 2, running SunOS 4 m68000-*-sunos4*
1320 Motorola 680x0 running LynxOS m68*-*-lynxos*
1321 AT&T 3b1/Unix pc m68*-att-*
1322 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1323 decstation mips-dec-* mips-little-*
1324 riscos mips-*-riscos* mips-*-sysv*
1325 sonymips mips-sony-*
1326 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1328 * REMOVED configurations and files
1330 SGI Irix-4.x mips-sgi-irix4 or iris4
1331 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1332 Z8000 simulator z8k-zilog-none or z8ksim
1333 Matsushita MN10200 w/simulator mn10200-*-*
1334 H8/500 simulator h8500-hitachi-hms or h8500hms
1335 HP/PA running BSD hppa*-*-bsd*
1336 HP/PA running OSF/1 hppa*-*-osf*
1337 HP/PA Pro target hppa*-*-pro*
1338 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1339 386BSD i[3456]86-*-bsd*
1340 Sequent family i[3456]86-sequent-sysv4*
1341 i[3456]86-sequent-sysv*
1342 i[3456]86-sequent-bsd*
1343 SPARC running LynxOS sparc-*-lynxos*
1344 SPARC running SunOS 4 sparc-*-sunos4*
1345 Tsqware Sparclet sparclet-*-*
1346 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1348 *** Changes in GDB 6.0:
1352 Support for debugging the Objective-C programming language has been
1353 integrated into GDB.
1355 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1357 DWARF 2's Call Frame Information makes available compiler generated
1358 information that more exactly describes the program's run-time stack.
1359 By using this information, GDB is able to provide more robust stack
1362 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1363 have been updated to use a new backtrace mechanism which includes
1364 DWARF 2 CFI support.
1368 GDB's remote protocol has been extended to include support for hosted
1369 file I/O (where the remote target uses GDB's file system). See GDB's
1370 remote protocol documentation for details.
1372 * All targets using the new architecture framework.
1374 All of GDB's targets have been updated to use the new internal
1375 architecture framework. The way is now open for future GDB releases
1376 to include cross-architecture native debugging support (i386 on amd64,
1379 * GNU/Linux's Thread Local Storage (TLS)
1381 GDB now includes support for for the GNU/Linux implementation of
1382 per-thread variables.
1384 * GNU/Linux's Native POSIX Thread Library (NPTL)
1386 GDB's thread code has been updated to work with either the new
1387 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1389 * Separate debug info.
1391 GDB, in conjunction with BINUTILS, now supports a mechanism for
1392 automatically loading debug information from a separate file. Instead
1393 of shipping full debug and non-debug versions of system libraries,
1394 system integrators can now instead ship just the stripped libraries
1395 and optional debug files.
1397 * DWARF 2 Location Expressions
1399 DWARF 2 Location Expressions allow the compiler to more completely
1400 describe the location of variables (even in optimized code) to the
1403 GDB now includes preliminary support for location expressions (support
1404 for DW_OP_piece is still missing).
1408 A number of long standing bugs that caused GDB to die while starting a
1409 Java application have been fixed. GDB's Java support is now
1410 considered "useable".
1412 * GNU/Linux support for fork, vfork, and exec.
1414 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1415 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1418 * GDB supports logging output to a file
1420 There are two new commands, "set logging" and "show logging", which can be
1421 used to capture GDB's output to a file.
1423 * The meaning of "detach" has changed for gdbserver
1425 The "detach" command will now resume the application, as documented. To
1426 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1429 * d10v, m68hc11 `regs' command deprecated
1431 The `info registers' command has been updated so that it displays the
1432 registers using a format identical to the old `regs' command.
1436 A new command, "maint set profile on/off", has been added. This command can
1437 be used to enable or disable profiling while running GDB, to profile a
1438 session or a set of commands. In addition there is a new configure switch,
1439 "--enable-profiling", which will cause GDB to be compiled with profiling
1440 data, for more informative profiling results.
1442 * Default MI syntax changed to "mi2".
1444 The default MI (machine interface) syntax, enabled by the command line
1445 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1446 "mi1", can be enabled by specifying the option "-i=mi1".
1448 Support for the original "mi0" syntax (included in GDB 5.0) has been
1451 Fix for gdb/192: removed extraneous space when displaying frame level.
1452 Fix for gdb/672: update changelist is now output in mi list format.
1453 Fix for gdb/702: a -var-assign that updates the value now shows up
1454 in a subsequent -var-update.
1456 * New native configurations.
1458 FreeBSD/amd64 x86_64-*-freebsd*
1460 * Multi-arched targets.
1462 HP/PA HPUX11 hppa*-*-hpux*
1463 Renesas M32R/D w/simulator m32r-*-elf*
1465 * OBSOLETE configurations and files
1467 Configurations that have been declared obsolete in this release have
1468 been commented out. Unless there is activity to revive these
1469 configurations, the next release of GDB will have their sources
1470 permanently REMOVED.
1472 Z8000 simulator z8k-zilog-none or z8ksim
1473 Matsushita MN10200 w/simulator mn10200-*-*
1474 H8/500 simulator h8500-hitachi-hms or h8500hms
1475 HP/PA running BSD hppa*-*-bsd*
1476 HP/PA running OSF/1 hppa*-*-osf*
1477 HP/PA Pro target hppa*-*-pro*
1478 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1479 Sequent family i[3456]86-sequent-sysv4*
1480 i[3456]86-sequent-sysv*
1481 i[3456]86-sequent-bsd*
1482 Tsqware Sparclet sparclet-*-*
1483 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1485 * REMOVED configurations and files
1488 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1489 IBM AIX PS/2 i[3456]86-*-aix
1490 i386 running Mach 3.0 i[3456]86-*-mach3*
1491 i386 running Mach i[3456]86-*-mach*
1492 i386 running OSF/1 i[3456]86-*osf1mk*
1493 HP/Apollo 68k Family m68*-apollo*-sysv*,
1495 m68*-hp-bsd*, m68*-hp-hpux*
1496 Argonaut Risc Chip (ARC) arc-*-*
1497 Mitsubishi D30V d30v-*-*
1498 Fujitsu FR30 fr30-*-elf*
1499 OS/9000 i[34]86-*-os9k
1500 I960 with MON960 i960-*-coff
1502 * MIPS $fp behavior changed
1504 The convenience variable $fp, for the MIPS, now consistently returns
1505 the address of the current frame's base. Previously, depending on the
1506 context, $fp could refer to either $sp or the current frame's base
1507 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1508 The GNU Source-Level Debugger''.
1510 *** Changes in GDB 5.3:
1512 * GNU/Linux shared library multi-threaded performance improved.
1514 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1515 `/proc', in preference to `ptrace' for memory reads. This may result
1516 in an improvement in the start-up time of multi-threaded, shared
1517 library applications when run under GDB. One GDB user writes: ``loads
1518 shared libs like mad''.
1520 * ``gdbserver'' now supports multi-threaded applications on some targets
1522 Support for debugging multi-threaded applications which use
1523 the GNU/Linux LinuxThreads package has been added for
1524 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1525 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1527 * GDB now supports C/C++ preprocessor macros.
1529 GDB now expands preprocessor macro invocations in C/C++ expressions,
1530 and provides various commands for showing macro definitions and how
1533 The new command `macro expand EXPRESSION' expands any macro
1534 invocations in expression, and shows the result.
1536 The new command `show macro MACRO-NAME' shows the definition of the
1537 macro named MACRO-NAME, and where it was defined.
1539 Most compilers don't include information about macros in the debugging
1540 information by default. In GCC 3.1, for example, you need to compile
1541 your program with the options `-gdwarf-2 -g3'. If the macro
1542 information is present in the executable, GDB will read it.
1544 * Multi-arched targets.
1546 DEC Alpha (partial) alpha*-*-*
1547 DEC VAX (partial) vax-*-*
1549 National Semiconductor NS32000 (partial) ns32k-*-*
1550 Motorola 68000 (partial) m68k-*-*
1551 Motorola MCORE mcore-*-*
1555 Fujitsu FRV architecture added by Red Hat frv*-*-*
1558 * New native configurations
1560 Alpha NetBSD alpha*-*-netbsd*
1561 SH NetBSD sh*-*-netbsdelf*
1562 MIPS NetBSD mips*-*-netbsd*
1563 UltraSPARC NetBSD sparc64-*-netbsd*
1565 * OBSOLETE configurations and files
1567 Configurations that have been declared obsolete in this release have
1568 been commented out. Unless there is activity to revive these
1569 configurations, the next release of GDB will have their sources
1570 permanently REMOVED.
1572 Mitsubishi D30V d30v-*-*
1573 OS/9000 i[34]86-*-os9k
1574 IBM AIX PS/2 i[3456]86-*-aix
1575 Fujitsu FR30 fr30-*-elf*
1576 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1577 Argonaut Risc Chip (ARC) arc-*-*
1578 i386 running Mach 3.0 i[3456]86-*-mach3*
1579 i386 running Mach i[3456]86-*-mach*
1580 i386 running OSF/1 i[3456]86-*osf1mk*
1581 HP/Apollo 68k Family m68*-apollo*-sysv*,
1583 m68*-hp-bsd*, m68*-hp-hpux*
1584 I960 with MON960 i960-*-coff
1586 * OBSOLETE languages
1588 CHILL, a Pascal like language used by telecommunications companies.
1590 * REMOVED configurations and files
1592 AMD 29k family via UDI a29k-amd-udi, udi29k
1593 A29K VxWorks a29k-*-vxworks
1594 AMD 29000 embedded, using EBMON a29k-none-none
1595 AMD 29000 embedded with COFF a29k-none-coff
1596 AMD 29000 embedded with a.out a29k-none-aout
1598 testsuite/gdb.hp/gdb.threads-hp/ directory
1600 * New command "set max-user-call-depth <nnn>"
1602 This command allows the user to limit the call depth of user-defined
1603 commands. The default is 1024.
1605 * Changes in FreeBSD/i386 native debugging.
1607 Support for the "generate-core-file" has been added.
1609 * New commands "dump", "append", and "restore".
1611 These commands allow data to be copied from target memory
1612 to a bfd-format or binary file (dump and append), and back
1613 from a file into memory (restore).
1615 * Improved "next/step" support on multi-processor Alpha Tru64.
1617 The previous single-step mechanism could cause unpredictable problems,
1618 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1619 of a software single-step mechanism prevents this.
1621 *** Changes in GDB 5.2.1:
1629 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1630 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1631 Fix, by Joel Brobecker imported from mainline.
1633 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1634 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1635 Fix, by Fred Fish, imported from mainline.
1637 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1638 Surprisingly enough, it works now.
1639 By Michal Ludvig, imported from mainline.
1641 i386 hardware watchpoint support:
1642 avoid misses on second run for some targets.
1643 By Pierre Muller, imported from mainline.
1645 *** Changes in GDB 5.2:
1647 * New command "set trust-readonly-sections on[off]".
1649 This command is a hint that tells gdb that read-only sections
1650 really are read-only (ie. that their contents will not change).
1651 In this mode, gdb will go to the object file rather than the
1652 target to read memory from read-only sections (such as ".text").
1653 This can be a significant performance improvement on some
1654 (notably embedded) targets.
1656 * New command "generate-core-file" (or "gcore").
1658 This new gdb command allows the user to drop a core file of the child
1659 process state at any time. So far it's been implemented only for
1660 GNU/Linux and Solaris, but should be relatively easily ported to other
1661 hosts. Argument is core file name (defaults to core.<pid>).
1663 * New command line option
1665 GDB now accepts --pid or -p followed by a process id.
1667 * Change in command line behavior -- corefiles vs. process ids.
1669 There is a subtle behavior in the way in which GDB handles
1670 command line arguments. The first non-flag argument is always
1671 a program to debug, but the second non-flag argument may either
1672 be a corefile or a process id. Previously, GDB would attempt to
1673 open the second argument as a corefile, and if that failed, would
1674 issue a superfluous error message and then attempt to attach it as
1675 a process. Now, if the second argument begins with a non-digit,
1676 it will be treated as a corefile. If it begins with a digit,
1677 GDB will attempt to attach it as a process, and if no such process
1678 is found, will then attempt to open it as a corefile.
1680 * Changes in ARM configurations.
1682 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1683 configuration is fully multi-arch.
1685 * New native configurations
1687 ARM NetBSD arm*-*-netbsd*
1688 x86 OpenBSD i[3456]86-*-openbsd*
1689 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1690 Sparc64 running FreeBSD sparc64-*-freebsd*
1694 Sanyo XStormy16 xstormy16-elf
1696 * OBSOLETE configurations and files
1698 Configurations that have been declared obsolete in this release have
1699 been commented out. Unless there is activity to revive these
1700 configurations, the next release of GDB will have their sources
1701 permanently REMOVED.
1703 AMD 29k family via UDI a29k-amd-udi, udi29k
1704 A29K VxWorks a29k-*-vxworks
1705 AMD 29000 embedded, using EBMON a29k-none-none
1706 AMD 29000 embedded with COFF a29k-none-coff
1707 AMD 29000 embedded with a.out a29k-none-aout
1709 testsuite/gdb.hp/gdb.threads-hp/ directory
1711 * REMOVED configurations and files
1713 TI TMS320C80 tic80-*-*
1715 PowerPC Solaris powerpcle-*-solaris*
1716 PowerPC Windows NT powerpcle-*-cygwin32
1717 PowerPC Netware powerpc-*-netware*
1718 Harris/CXUX m88k m88*-harris-cxux*
1719 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1720 ns32k-utek-sysv* ns32k-utek-*
1721 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1722 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1723 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1724 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1725 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1727 * Changes to command line processing
1729 The new `--args' feature can be used to specify command-line arguments
1730 for the inferior from gdb's command line.
1732 * Changes to key bindings
1734 There is a new `operate-and-get-next' function bound to `C-o'.
1736 *** Changes in GDB 5.1.1
1738 Fix compile problem on DJGPP.
1740 Fix a problem with floating-point registers on the i386 being
1743 Fix to stop GDB crashing on .debug_str debug info.
1745 Numerous documentation fixes.
1747 Numerous testsuite fixes.
1749 *** Changes in GDB 5.1:
1751 * New native configurations
1753 Alpha FreeBSD alpha*-*-freebsd*
1754 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1755 MIPS GNU/Linux mips*-*-linux*
1756 MIPS SGI Irix 6.x mips*-sgi-irix6*
1757 ia64 AIX ia64-*-aix*
1758 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1762 Motorola 68HC11 and 68HC12 m68hc11-elf
1764 UltraSparc running GNU/Linux sparc64-*-linux*
1766 * OBSOLETE configurations and files
1768 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1769 Harris/CXUX m88k m88*-harris-cxux*
1770 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1771 ns32k-utek-sysv* ns32k-utek-*
1772 TI TMS320C80 tic80-*-*
1774 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1775 PowerPC Solaris powerpcle-*-solaris*
1776 PowerPC Windows NT powerpcle-*-cygwin32
1777 PowerPC Netware powerpc-*-netware*
1778 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1779 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1780 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1781 Apple Macintosh (MPW) host N/A
1783 stuff.c (Program to stuff files into a specially prepared space in kdb)
1784 kdb-start.c (Main loop for the standalone kernel debugger)
1786 Configurations that have been declared obsolete in this release have
1787 been commented out. Unless there is activity to revive these
1788 configurations, the next release of GDB will have their sources
1789 permanently REMOVED.
1791 * REMOVED configurations and files
1793 Altos 3068 m68*-altos-*
1794 Convex c1-*-*, c2-*-*
1796 ARM RISCix arm-*-* (as host)
1800 * GDB has been converted to ISO C.
1802 GDB's source code has been converted to ISO C. In particular, the
1803 sources are fully protoized, and rely on standard headers being
1808 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1810 * The MI enabled by default.
1812 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1813 revised and enabled by default. Packages which use GDB as a debugging
1814 engine behind a UI or another front end are encouraged to switch to
1815 using the GDB/MI interface, instead of the old annotations interface
1816 which is now deprecated.
1818 * Support for debugging Pascal programs.
1820 GDB now includes support for debugging Pascal programs. The following
1821 main features are supported:
1823 - Pascal-specific data types such as sets;
1825 - automatic recognition of Pascal sources based on file-name
1828 - Pascal-style display of data types, variables, and functions;
1830 - a Pascal expression parser.
1832 However, some important features are not yet supported.
1834 - Pascal string operations are not supported at all;
1836 - there are some problems with boolean types;
1838 - Pascal type hexadecimal constants are not supported
1839 because they conflict with the internal variables format;
1841 - support for Pascal objects and classes is not full yet;
1843 - unlike Pascal, GDB is case-sensitive for symbol names.
1845 * Changes in completion.
1847 Commands such as `shell', `run' and `set args', which pass arguments
1848 to inferior programs, now complete on file names, similar to what
1849 users expect at the shell prompt.
1851 Commands which accept locations, such as `disassemble', `print',
1852 `breakpoint', `until', etc. now complete on filenames as well as
1853 program symbols. Thus, if you type "break foob TAB", and the source
1854 files linked into the programs include `foobar.c', that file name will
1855 be one of the candidates for completion. However, file names are not
1856 considered for completion after you typed a colon that delimits a file
1857 name from a name of a function in that file, as in "break foo.c:bar".
1859 `set demangle-style' completes on available demangling styles.
1861 * New platform-independent commands:
1863 It is now possible to define a post-hook for a command as well as a
1864 hook that runs before the command. For more details, see the
1865 documentation of `hookpost' in the GDB manual.
1867 * Changes in GNU/Linux native debugging.
1869 Support for debugging multi-threaded programs has been completely
1870 revised for all platforms except m68k and sparc. You can now debug as
1871 many threads as your system allows you to have.
1873 Attach/detach is supported for multi-threaded programs.
1875 Support for SSE registers was added for x86. This doesn't work for
1876 multi-threaded programs though.
1878 * Changes in MIPS configurations.
1880 Multi-arch support is enabled for all MIPS configurations.
1882 GDB can now be built as native debugger on SGI Irix 6.x systems for
1883 debugging n32 executables. (Debugging 64-bit executables is not yet
1886 * Unified support for hardware watchpoints in all x86 configurations.
1888 Most (if not all) native x86 configurations support hardware-assisted
1889 breakpoints and watchpoints in a unified manner. This support
1890 implements debug register sharing between watchpoints, which allows to
1891 put a virtually infinite number of watchpoints on the same address,
1892 and also supports watching regions up to 16 bytes with several debug
1895 The new maintenance command `maintenance show-debug-regs' toggles
1896 debugging print-outs in functions that insert, remove, and test
1897 watchpoints and hardware breakpoints.
1899 * Changes in the DJGPP native configuration.
1901 New command ``info dos sysinfo'' displays assorted information about
1902 the CPU, OS, memory, and DPMI server.
1904 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1905 display information about segment descriptors stored in GDT, LDT, and
1908 New commands ``info dos pde'' and ``info dos pte'' display entries
1909 from Page Directory and Page Tables (for now works with CWSDPMI only).
1910 New command ``info dos address-pte'' displays the Page Table entry for
1911 a given linear address.
1913 GDB can now pass command lines longer than 126 characters to the
1914 program being debugged (requires an update to the libdbg.a library
1915 which is part of the DJGPP development kit).
1917 DWARF2 debug info is now supported.
1919 It is now possible to `step' and `next' through calls to `longjmp'.
1921 * Changes in documentation.
1923 All GDB documentation was converted to GFDL, the GNU Free
1924 Documentation License.
1926 Tracepoints-related commands are now fully documented in the GDB
1929 TUI, the Text-mode User Interface, is now documented in the manual.
1931 Tracepoints-related commands are now fully documented in the GDB
1934 The "GDB Internals" manual now has an index. It also includes
1935 documentation of `ui_out' functions, GDB coding standards, x86
1936 hardware watchpoints, and memory region attributes.
1938 * GDB's version number moved to ``version.in''
1940 The Makefile variable VERSION has been replaced by the file
1941 ``version.in''. People creating GDB distributions should update the
1942 contents of this file.
1946 GUD support is now a standard part of the EMACS distribution.
1948 *** Changes in GDB 5.0:
1950 * Improved support for debugging FP programs on x86 targets
1952 Unified and much-improved support for debugging floating-point
1953 programs on all x86 targets. In particular, ``info float'' now
1954 displays the FP registers in the same format on all x86 targets, with
1955 greater level of detail.
1957 * Improvements and bugfixes in hardware-assisted watchpoints
1959 It is now possible to watch array elements, struct members, and
1960 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1961 on x86 targets no longer erroneously trigger when the address is
1964 * Improvements in the native DJGPP version of GDB
1966 The distribution now includes all the scripts and auxiliary files
1967 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1968 machines ``out of the box''.
1970 The DJGPP version can now debug programs that use signals. It is
1971 possible to catch signals that happened in the debuggee, deliver
1972 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1973 would kill the program being debugged.) Programs that hook hardware
1974 interrupts (keyboard, timer, etc.) can also be debugged.
1976 It is now possible to debug DJGPP programs that redirect their
1977 standard handles or switch them to raw (as opposed to cooked) mode, or
1978 even close them. The command ``run < foo > bar'' works as expected,
1979 and ``info terminal'' reports useful information about the debuggee's
1980 terminal, including raw/cooked mode, redirection, etc.
1982 The DJGPP version now uses termios functions for console I/O, which
1983 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1986 DOS-style file names with drive letters are now fully supported by
1989 It is now possible to debug DJGPP programs that switch their working
1990 directory. It is also possible to rerun the debuggee any number of
1991 times without restarting GDB; thus, you can use the same setup,
1992 breakpoints, etc. for many debugging sessions.
1994 * New native configurations
1996 ARM GNU/Linux arm*-*-linux*
1997 PowerPC GNU/Linux powerpc-*-linux*
2001 Motorola MCore mcore-*-*
2002 x86 VxWorks i[3456]86-*-vxworks*
2003 PowerPC VxWorks powerpc-*-vxworks*
2004 TI TMS320C80 tic80-*-*
2006 * OBSOLETE configurations
2008 Altos 3068 m68*-altos-*
2009 Convex c1-*-*, c2-*-*
2011 ARM RISCix arm-*-* (as host)
2014 Configurations that have been declared obsolete will be commented out,
2015 but the code will be left in place. If there is no activity to revive
2016 these configurations before the next release of GDB, the sources will
2017 be permanently REMOVED.
2019 * Gould support removed
2021 Support for the Gould PowerNode and NP1 has been removed.
2023 * New features for SVR4
2025 On SVR4 native platforms (such as Solaris), if you attach to a process
2026 without first loading a symbol file, GDB will now attempt to locate and
2027 load symbols from the running process's executable file.
2029 * Many C++ enhancements
2031 C++ support has been greatly improved. Overload resolution now works properly
2032 in almost all cases. RTTI support is on the way.
2034 * Remote targets can connect to a sub-program
2036 A popen(3) style serial-device has been added. This device starts a
2037 sub-process (such as a stand-alone simulator) and then communicates
2038 with that. The sub-program to run is specified using the syntax
2039 ``|<program> <args>'' vis:
2041 (gdb) set remotedebug 1
2042 (gdb) target extended-remote |mn10300-elf-sim program-args
2044 * MIPS 64 remote protocol
2046 A long standing bug in the mips64 remote protocol where by GDB
2047 expected certain 32 bit registers (ex SR) to be transfered as 32
2048 instead of 64 bits has been fixed.
2050 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2051 added to provide backward compatibility with older versions of GDB.
2053 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2055 The command ``set remotebinarydownload'' command has been replaced by
2056 ``set remote X-packet''. Other commands in ``set remote'' family
2057 include ``set remote P-packet''.
2059 * Breakpoint commands accept ranges.
2061 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2062 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2063 ``tracepoint passcount'' also accepts a range of tracepoints.
2065 * ``apropos'' command added.
2067 The ``apropos'' command searches through command names and
2068 documentation strings, printing out matches, making it much easier to
2069 try to find a command that does what you are looking for.
2073 A new machine oriented interface (MI) has been added to GDB. This
2074 interface is designed for debug environments running GDB as a separate
2075 process. This is part of the long term libGDB project. See the
2076 "GDB/MI" chapter of the GDB manual for further information. It can be
2077 enabled by configuring with:
2079 .../configure --enable-gdbmi
2081 *** Changes in GDB-4.18:
2083 * New native configurations
2085 HP-UX 10.20 hppa*-*-hpux10.20
2086 HP-UX 11.x hppa*-*-hpux11.0*
2087 M68K GNU/Linux m68*-*-linux*
2091 Fujitsu FR30 fr30-*-elf*
2092 Intel StrongARM strongarm-*-*
2093 Mitsubishi D30V d30v-*-*
2095 * OBSOLETE configurations
2097 Gould PowerNode, NP1 np1-*-*, pn-*-*
2099 Configurations that have been declared obsolete will be commented out,
2100 but the code will be left in place. If there is no activity to revive
2101 these configurations before the next release of GDB, the sources will
2102 be permanently REMOVED.
2106 As a compatibility experiment, GDB's source files buildsym.h and
2107 buildsym.c have been converted to pure standard C, no longer
2108 containing any K&R compatibility code. We believe that all systems in
2109 use today either come with a standard C compiler, or have a GCC port
2110 available. If this is not true, please report the affected
2111 configuration to bug-gdb@gnu.org immediately. See the README file for
2112 information about getting a standard C compiler if you don't have one
2117 GDB now uses readline 2.2.
2119 * set extension-language
2121 You can now control the mapping between filename extensions and source
2122 languages by using the `set extension-language' command. For instance,
2123 you can ask GDB to treat .c files as C++ by saying
2124 set extension-language .c c++
2125 The command `info extensions' lists all of the recognized extensions
2126 and their associated languages.
2128 * Setting processor type for PowerPC and RS/6000
2130 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2131 you can use the `set processor' command to specify what variant of the
2132 PowerPC family you are debugging. The command
2136 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2137 following PowerPC and RS6000 variants:
2139 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2140 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2142 403GC IBM PowerPC 403GC
2143 505 Motorola PowerPC 505
2144 860 Motorola PowerPC 860 or 850
2145 601 Motorola PowerPC 601
2146 602 Motorola PowerPC 602
2147 603 Motorola/IBM PowerPC 603 or 603e
2148 604 Motorola PowerPC 604 or 604e
2149 750 Motorola/IBM PowerPC 750 or 750
2151 At the moment, this command just tells GDB what to name the
2152 special-purpose processor registers. Since almost all the affected
2153 registers are inaccessible to user-level programs, this command is
2154 only useful for remote debugging in its present form.
2158 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2159 more extensive support for HP-UX. Added features include shared
2160 library support, kernel threads and hardware watchpoints for 11.00,
2161 support for HP's ANSI C and C++ compilers, and a compatibility mode
2162 for xdb and dbx commands.
2166 HP's donation includes the new concept of catchpoints, which is a
2167 generalization of the old catch command. On HP-UX, it is now possible
2168 to catch exec, fork, and vfork, as well as library loading.
2170 This means that the existing catch command has changed; its first
2171 argument now specifies the type of catch to be set up. See the
2172 output of "help catch" for a list of catchpoint types.
2174 * Debugging across forks
2176 On HP-UX, you can choose which process to debug when a fork() happens
2181 HP has donated a curses-based terminal user interface (TUI). To get
2182 it, build with --enable-tui. Although this can be enabled for any
2183 configuration, at present it only works for native HP debugging.
2185 * GDB remote protocol additions
2187 A new protocol packet 'X' that writes binary data is now available.
2188 Default behavior is to try 'X', then drop back to 'M' if the stub
2189 fails to respond. The settable variable `remotebinarydownload'
2190 allows explicit control over the use of 'X'.
2192 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2193 full 64-bit address. The command
2195 set remoteaddresssize 32
2197 can be used to revert to the old behaviour. For existing remote stubs
2198 the change should not be noticed, as the additional address information
2201 In order to assist in debugging stubs, you may use the maintenance
2202 command `packet' to send any text string to the stub. For instance,
2204 maint packet heythere
2206 sends the packet "$heythere#<checksum>". Note that it is very easy to
2207 disrupt a debugging session by sending the wrong packet at the wrong
2210 The compare-sections command allows you to compare section data on the
2211 target to what is in the executable file without uploading or
2212 downloading, by comparing CRC checksums.
2214 * Tracing can collect general expressions
2216 You may now collect general expressions at tracepoints. This requires
2217 further additions to the target-side stub; see tracepoint.c and
2218 doc/agentexpr.texi for further details.
2220 * mask-address variable for Mips
2222 For Mips targets, you may control the zeroing of the upper 32 bits of
2223 a 64-bit address by entering `set mask-address on'. This is mainly
2224 of interest to users of embedded R4xxx and R5xxx processors.
2226 * Higher serial baud rates
2228 GDB's serial code now allows you to specify baud rates 57600, 115200,
2229 230400, and 460800 baud. (Note that your host system may not be able
2230 to achieve all of these rates.)
2234 The i960 configuration now includes an initial implementation of a
2235 builtin simulator, contributed by Jim Wilson.
2238 *** Changes in GDB-4.17:
2240 * New native configurations
2242 Alpha GNU/Linux alpha*-*-linux*
2243 Unixware 2.x i[3456]86-unixware2*
2244 Irix 6.x mips*-sgi-irix6*
2245 PowerPC GNU/Linux powerpc-*-linux*
2246 PowerPC Solaris powerpcle-*-solaris*
2247 Sparc GNU/Linux sparc-*-linux*
2248 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2252 Argonaut Risc Chip (ARC) arc-*-*
2253 Hitachi H8/300S h8300*-*-*
2254 Matsushita MN10200 w/simulator mn10200-*-*
2255 Matsushita MN10300 w/simulator mn10300-*-*
2256 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2257 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2258 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2259 Mitsubishi D10V w/simulator d10v-*-*
2260 Mitsubishi M32R/D w/simulator m32r-*-elf*
2261 Tsqware Sparclet sparclet-*-*
2262 NEC V850 w/simulator v850-*-*
2264 * New debugging protocols
2266 ARM with RDI protocol arm*-*-*
2267 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2268 DDB and LSI variants of PMON protocol mips*-*-*
2269 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2270 PowerPC with SDS protocol powerpc{,le}-*-eabi
2271 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2275 All configurations can now understand and use the DWARF 2 debugging
2276 format. The choice is automatic, if the symbol file contains DWARF 2
2281 GDB now includes basic Java language support. This support is
2282 only useful with Java compilers that produce native machine code.
2284 * solib-absolute-prefix and solib-search-path
2286 For SunOS and SVR4 shared libraries, you may now set the prefix for
2287 loading absolute shared library symbol files, and the search path for
2288 locating non-absolute shared library symbol files.
2290 * Live range splitting
2292 GDB can now effectively debug code for which GCC has performed live
2293 range splitting as part of its optimization. See gdb/doc/LRS for
2294 more details on the expected format of the stabs information.
2298 GDB's support for the GNU Hurd, including thread debugging, has been
2299 updated to work with current versions of the Hurd.
2303 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2304 instruction set. ARM GDB automatically detects when Thumb
2305 instructions are in use, and adjusts disassembly and backtracing
2310 GDB's MIPS target configurations now handle the MIP16 16-bit
2315 GDB now includes support for overlays; if an executable has been
2316 linked such that multiple sections are based at the same address, GDB
2317 will decide which section to use for symbolic info. You can choose to
2318 control the decision manually, using overlay commands, or implement
2319 additional target-side support and use "overlay load-target" to bring
2320 in the overlay mapping. Do "help overlay" for more detail.
2324 The command "info symbol <address>" displays information about
2325 the symbol at the specified address.
2329 The standard remote protocol now includes an extension that allows
2330 asynchronous collection and display of trace data. This requires
2331 extensive support in the target-side debugging stub. Tracing mode
2332 includes a new interaction mode in GDB and new commands: see the
2333 file tracepoint.c for more details.
2337 Configurations for embedded MIPS now include a simulator contributed
2338 by Cygnus Solutions. The simulator supports the instruction sets
2339 of most MIPS variants.
2343 Sparc configurations may now include the ERC32 simulator contributed
2344 by the European Space Agency. The simulator is not built into
2345 Sparc targets by default; configure with --enable-sim to include it.
2349 For target configurations that may include multiple variants of a
2350 basic architecture (such as MIPS and SH), you may now set the
2351 architecture explicitly. "set arch" sets, "info arch" lists
2352 the possible architectures.
2354 *** Changes in GDB-4.16:
2356 * New native configurations
2358 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2359 M68K NetBSD m68k-*-netbsd*
2360 PowerPC AIX 4.x powerpc-*-aix*
2361 PowerPC MacOS powerpc-*-macos*
2362 PowerPC Windows NT powerpcle-*-cygwin32
2363 RS/6000 AIX 4.x rs6000-*-aix4*
2367 ARM with RDP protocol arm-*-*
2368 I960 with MON960 i960-*-coff
2369 MIPS VxWorks mips*-*-vxworks*
2370 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2371 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2373 Matra Sparclet sparclet-*-*
2377 The powerpc-eabi configuration now includes the PSIM simulator,
2378 contributed by Andrew Cagney, with assistance from Mike Meissner.
2379 PSIM is a very elaborate model of the PowerPC, including not only
2380 basic instruction set execution, but also details of execution unit
2381 performance and I/O hardware. See sim/ppc/README for more details.
2385 GDB now works with Solaris 2.5.
2387 * Windows 95/NT native
2389 GDB will now work as a native debugger on Windows 95 and Windows NT.
2390 To build it from source, you must use the "gnu-win32" environment,
2391 which uses a DLL to emulate enough of Unix to run the GNU tools.
2392 Further information, binaries, and sources are available at
2393 ftp.cygnus.com, under pub/gnu-win32.
2395 * dont-repeat command
2397 If a user-defined command includes the command `dont-repeat', then the
2398 command will not be repeated if the user just types return. This is
2399 useful if the command is time-consuming to run, so that accidental
2400 extra keystrokes don't run the same command many times.
2402 * Send break instead of ^C
2404 The standard remote protocol now includes an option to send a break
2405 rather than a ^C to the target in order to interrupt it. By default,
2406 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2408 * Remote protocol timeout
2410 The standard remote protocol includes a new variable `remotetimeout'
2411 that allows you to set the number of seconds before GDB gives up trying
2412 to read from the target. The default value is 2.
2414 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2416 By default GDB will automatically keep track of objects as they are
2417 loaded and unloaded by the dynamic linker. By using the command `set
2418 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2419 when shared library events occur, thus allowing you to set breakpoints
2420 in shared libraries which are explicitly loaded by the inferior.
2422 Note this feature does not work on hpux8. On hpux9 you must link
2423 /usr/lib/end.o into your program. This feature should work
2424 automatically on hpux10.
2426 * Irix 5.x hardware watchpoint support
2428 Irix 5 configurations now support the use of hardware watchpoints.
2430 * Mips protocol "SYN garbage limit"
2432 When debugging a Mips target using the `target mips' protocol, you
2433 may set the number of characters that GDB will ignore by setting
2434 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2435 every character. The default value is 1050.
2437 * Recording and replaying remote debug sessions
2439 If you set `remotelogfile' to the name of a file, gdb will write to it
2440 a recording of a remote debug session. This recording may then be
2441 replayed back to gdb using "gdbreplay". See gdbserver/README for
2442 details. This is useful when you have a problem with GDB while doing
2443 remote debugging; you can make a recording of the session and send it
2444 to someone else, who can then recreate the problem.
2446 * Speedups for remote debugging
2448 GDB includes speedups for downloading and stepping MIPS systems using
2449 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2450 and more efficient S-record downloading.
2452 * Memory use reductions and statistics collection
2454 GDB now uses less memory and reports statistics about memory usage.
2455 Try the `maint print statistics' command, for example.
2457 *** Changes in GDB-4.15:
2459 * Psymtabs for XCOFF
2461 The symbol reader for AIX GDB now uses partial symbol tables. This
2462 can greatly improve startup time, especially for large executables.
2464 * Remote targets use caching
2466 Remote targets now use a data cache to speed up communication with the
2467 remote side. The data cache could lead to incorrect results because
2468 it doesn't know about volatile variables, thus making it impossible to
2469 debug targets which use memory mapped I/O devices. `set remotecache
2470 off' turns the the data cache off.
2472 * Remote targets may have threads
2474 The standard remote protocol now includes support for multiple threads
2475 in the target system, using new protocol commands 'H' and 'T'. See
2476 gdb/remote.c for details.
2480 If GDB is configured with `--enable-netrom', then it will include
2481 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2482 acts as though it is a bank of ROM on the target board, but you can
2483 write into it over the network. GDB's support consists only of
2484 support for fast loading into the emulated ROM; to debug, you must use
2485 another protocol, such as standard remote protocol. The usual
2486 sequence is something like
2488 target nrom <netrom-hostname>
2490 target remote <netrom-hostname>:1235
2494 GDB now includes support for the Apple Macintosh, as a host only. It
2495 may be run as either an MPW tool or as a standalone application, and
2496 it can debug through the serial port. All the usual GDB commands are
2497 available, but to the target command, you must supply "serial" as the
2498 device type instead of "/dev/ttyXX". See mpw-README in the main
2499 directory for more information on how to build. The MPW configuration
2500 scripts */mpw-config.in support only a few targets, and only the
2501 mips-idt-ecoff target has been tested.
2505 GDB configuration now uses autoconf. This is not user-visible,
2506 but does simplify configuration and building.
2510 GDB now supports hpux10.
2512 *** Changes in GDB-4.14:
2514 * New native configurations
2516 x86 FreeBSD i[345]86-*-freebsd
2517 x86 NetBSD i[345]86-*-netbsd
2518 NS32k NetBSD ns32k-*-netbsd
2519 Sparc NetBSD sparc-*-netbsd
2523 A29K VxWorks a29k-*-vxworks
2524 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2525 CPU32 EST-300 emulator m68*-*-est*
2526 PowerPC ELF powerpc-*-elf
2529 * Alpha OSF/1 support for procfs
2531 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2532 possible to attach to running processes. As the mounting of the /proc
2533 filesystem is optional on the Alpha, GDB automatically determines
2534 the availability of /proc during startup. This can lead to problems
2535 if /proc is unmounted after GDB has been started.
2537 * Arguments to user-defined commands
2539 User commands may accept up to 10 arguments separated by whitespace.
2540 Arguments are accessed within the user command via $arg0..$arg9. A
2543 print $arg0 + $arg1 + $arg2
2545 To execute the command use:
2548 Defines the command "adder" which prints the sum of its three arguments.
2549 Note the arguments are text substitutions, so they may reference variables,
2550 use complex expressions, or even perform inferior function calls.
2552 * New `if' and `while' commands
2554 This makes it possible to write more sophisticated user-defined
2555 commands. Both commands take a single argument, which is the
2556 expression to evaluate, and must be followed by the commands to
2557 execute, one per line, if the expression is nonzero, the list being
2558 terminated by the word `end'. The `if' command list may include an
2559 `else' word, which causes the following commands to be executed only
2560 if the expression is zero.
2562 * Fortran source language mode
2564 GDB now includes partial support for Fortran 77. It will recognize
2565 Fortran programs and can evaluate a subset of Fortran expressions, but
2566 variables and functions may not be handled correctly. GDB will work
2567 with G77, but does not yet know much about symbols emitted by other
2570 * Better HPUX support
2572 Most debugging facilities now work on dynamic executables for HPPAs
2573 running hpux9 or later. You can attach to running dynamically linked
2574 processes, but by default the dynamic libraries will be read-only, so
2575 for instance you won't be able to put breakpoints in them. To change
2576 that behavior do the following before running the program:
2582 This will cause the libraries to be mapped private and read-write.
2583 To revert to the normal behavior, do this:
2589 You cannot set breakpoints or examine data in the library until after
2590 the library is loaded if the function/data symbols do not have
2593 GDB can now also read debug symbols produced by the HP C compiler on
2594 HPPAs (sorry, no C++, Fortran or 68k support).
2596 * Target byte order now dynamically selectable
2598 You can choose which byte order to use with a target system, via the
2599 commands "set endian big" and "set endian little", and you can see the
2600 current setting by using "show endian". You can also give the command
2601 "set endian auto", in which case GDB will use the byte order
2602 associated with the executable. Currently, only embedded MIPS
2603 configurations support dynamic selection of target byte order.
2605 * New DOS host serial code
2607 This version uses DPMI interrupts to handle buffered I/O, so you
2608 no longer need to run asynctsr when debugging boards connected to
2611 *** Changes in GDB-4.13:
2613 * New "complete" command
2615 This lists all the possible completions for the rest of the line, if it
2616 were to be given as a command itself. This is intended for use by emacs.
2618 * Trailing space optional in prompt
2620 "set prompt" no longer adds a space for you after the prompt you set. This
2621 allows you to set a prompt which ends in a space or one that does not.
2623 * Breakpoint hit counts
2625 "info break" now displays a count of the number of times the breakpoint
2626 has been hit. This is especially useful in conjunction with "ignore"; you
2627 can ignore a large number of breakpoint hits, look at the breakpoint info
2628 to see how many times the breakpoint was hit, then run again, ignoring one
2629 less than that number, and this will get you quickly to the last hit of
2632 * Ability to stop printing at NULL character
2634 "set print null-stop" will cause GDB to stop printing the characters of
2635 an array when the first NULL is encountered. This is useful when large
2636 arrays actually contain only short strings.
2638 * Shared library breakpoints
2640 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2641 breakpoints in shared libraries before the executable is run.
2643 * Hardware watchpoints
2645 There is a new hardware breakpoint for the watch command for sparclite
2646 targets. See gdb/sparclite/hw_breakpoint.note.
2648 Hardware watchpoints are also now supported under GNU/Linux.
2652 Annotations have been added. These are for use with graphical interfaces,
2653 and are still experimental. Currently only gdba.el uses these.
2655 * Improved Irix 5 support
2657 GDB now works properly with Irix 5.2.
2659 * Improved HPPA support
2661 GDB now works properly with the latest GCC and GAS.
2663 * New native configurations
2665 Sequent PTX4 i[34]86-sequent-ptx4
2666 HPPA running OSF/1 hppa*-*-osf*
2667 Atari TT running SVR4 m68*-*-sysv4*
2668 RS/6000 LynxOS rs6000-*-lynxos*
2672 OS/9000 i[34]86-*-os9k
2673 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2676 * Hitachi SH7000 and E7000-PC ICE support
2678 There is now support for communicating with the Hitachi E7000-PC ICE.
2679 This is available automatically when GDB is configured for the SH.
2683 As usual, a variety of small fixes and improvements, both generic
2684 and configuration-specific. See the ChangeLog for more detail.
2686 *** Changes in GDB-4.12:
2688 * Irix 5 is now supported
2692 GDB-4.12 on the HPPA has a number of changes which make it unable
2693 to debug the output from the currently released versions of GCC and
2694 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2695 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2696 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2699 *** Changes in GDB-4.11:
2701 * User visible changes:
2705 The "set remotedebug" option is now consistent between the mips remote
2706 target, remote targets using the gdb-specific protocol, UDI (AMD's
2707 debug protocol for the 29k) and the 88k bug monitor. It is now an
2708 integer specifying a debug level (normally 0 or 1, but 2 means more
2709 debugging info for the mips target).
2711 * DEC Alpha native support
2713 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2714 debug info, but GDB works fairly well with the DEC compiler and should
2715 work with a future GCC release. See the README file for a few
2716 Alpha-specific notes.
2718 * Preliminary thread implementation
2720 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2722 * LynxOS native and target support for 386
2724 This release has been hosted on LynxOS 2.2, and also can be configured
2725 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2728 * Improvements in C++ mangling/demangling.
2730 This release has much better g++ debugging, specifically in name
2731 mangling/demangling, virtual function calls, print virtual table,
2732 call methods, ...etc.
2734 *** Changes in GDB-4.10:
2736 * User visible changes:
2738 Remote debugging using the GDB-specific (`target remote') protocol now
2739 supports the `load' command. This is only useful if you have some
2740 other way of getting the stub to the target system, and you can put it
2741 somewhere in memory where it won't get clobbered by the download.
2743 Filename completion now works.
2745 When run under emacs mode, the "info line" command now causes the
2746 arrow to point to the line specified. Also, "info line" prints
2747 addresses in symbolic form (as well as hex).
2749 All vxworks based targets now support a user settable option, called
2750 vxworks-timeout. This option represents the number of seconds gdb
2751 should wait for responses to rpc's. You might want to use this if
2752 your vxworks target is, perhaps, a slow software simulator or happens
2753 to be on the far side of a thin network line.
2757 This release contains support for using a DEC alpha as a GDB host for
2758 cross debugging. Native alpha debugging is not supported yet.
2761 *** Changes in GDB-4.9:
2765 This is the first GDB release which is accompanied by a matching testsuite.
2766 The testsuite requires installation of dejagnu, which should be available
2767 via ftp from most sites that carry GNU software.
2771 'Cfront' style demangling has had its name changed to 'ARM' style, to
2772 emphasize that it was written from the specifications in the C++ Annotated
2773 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2774 disclaimers, it still generated too much confusion with users attempting to
2775 use gdb with AT&T cfront.
2779 GDB now uses a standard remote interface to a simulator library.
2780 So far, the library contains simulators for the Zilog Z8001/2, the
2781 Hitachi H8/300, H8/500 and Super-H.
2783 * New targets supported
2785 H8/300 simulator h8300-hitachi-hms or h8300hms
2786 H8/500 simulator h8500-hitachi-hms or h8500hms
2787 SH simulator sh-hitachi-hms or sh
2788 Z8000 simulator z8k-zilog-none or z8ksim
2789 IDT MIPS board over serial line mips-idt-ecoff
2791 Cross-debugging to GO32 targets is supported. It requires a custom
2792 version of the i386-stub.c module which is integrated with the
2793 GO32 memory extender.
2795 * New remote protocols
2797 MIPS remote debugging protocol.
2799 * New source languages supported
2801 This version includes preliminary support for Chill, a Pascal like language
2802 used by telecommunications companies. Chill support is also being integrated
2803 into the GNU compiler, but we don't know when it will be publically available.
2806 *** Changes in GDB-4.8:
2808 * HP Precision Architecture supported
2810 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2811 version of this support was available as a set of patches from the
2812 University of Utah. GDB does not support debugging of programs
2813 compiled with the HP compiler, because HP will not document their file
2814 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2815 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2817 Many problems in the preliminary version have been fixed.
2819 * Faster and better demangling
2821 We have improved template demangling and fixed numerous bugs in the GNU style
2822 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2823 character types (wchar_t) are now supported. Demangling of each symbol is now
2824 only done once, and is cached when the symbol table for a file is read in.
2825 This results in a small increase in memory usage for C programs, a moderate
2826 increase in memory usage for C++ programs, and a fantastic speedup in
2829 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2830 from the specifications in the Annotated Reference Manual, which AT&T's
2831 compiler does not actually implement.
2833 * G++ multiple inheritance compiler problem
2835 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2836 inheritance lattices was reworked to properly discover ambiguities. We
2837 recently found an example which causes this new algorithm to fail in a
2838 very subtle way, producing bad debug information for those classes.
2839 The file 'gcc.patch' (in this directory) can be applied to gcc to
2840 circumvent the problem. A future GCC release will contain a complete
2843 The previous G++ debug info problem (mentioned below for the gdb-4.7
2844 release) is fixed in gcc version 2.3.2.
2846 * Improved configure script
2848 The `configure' script will now attempt to guess your system type if
2849 you don't supply a host system type. The old scheme of supplying a
2850 host system triplet is preferable over using this. All the magic is
2851 done in the new `config.guess' script. Examine it for details.
2853 We have also brought our configure script much more in line with the FSF's
2854 version. It now supports the --with-xxx options. In particular,
2855 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2856 The resulting GDB will not be able to read arbitrary object file formats --
2857 only the format ``expected'' to be used on the configured target system.
2858 We hope to make this the default in a future release.
2860 * Documentation improvements
2862 There's new internal documentation on how to modify GDB, and how to
2863 produce clean changes to the code. We implore people to read it
2864 before submitting changes.
2866 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2867 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2868 `info' files are also provided. To build `info' files from scratch,
2869 you will need the latest `makeinfo' release, which will be available in
2870 a future texinfo-X.Y release.
2872 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2873 We're not sure exactly which versions have this problem, but it has
2874 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2875 or better. If that isn't possible, there is a patch in
2876 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2877 around this problem.
2881 GDB now supports array constants that can be used in expressions typed in by
2882 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2883 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2886 The new directory `gdb/sparclite' contains a program that demonstrates
2887 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2889 * New native hosts supported
2891 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2892 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2894 * New targets supported
2896 AMD 29k family via UDI a29k-amd-udi or udi29k
2898 * New file formats supported
2900 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2901 HPUX core files, and SCO 3.2v2 core files.
2905 Attaching to processes now works again; thanks for the many bug reports.
2907 We have also stomped on a bunch of core dumps caused by
2908 printf_filtered("%s") problems.
2910 We eliminated a copyright problem on the rpc and ptrace header files
2911 for VxWorks, which was discovered at the last minute during the 4.7
2912 release. You should now be able to build a VxWorks GDB.
2914 You can now interrupt gdb while an attached process is running. This
2915 will cause the attached process to stop, and give control back to GDB.
2917 We fixed problems caused by using too many file descriptors
2918 for reading symbols from object files and libraries. This was
2919 especially a problem for programs that used many (~100) shared
2922 The `step' command now only enters a subroutine if there is line number
2923 information for the subroutine. Otherwise it acts like the `next'
2924 command. Previously, `step' would enter subroutines if there was
2925 any debugging information about the routine. This avoids problems
2926 when using `cc -g1' on MIPS machines.
2928 * Internal improvements
2930 GDB's internal interfaces have been improved to make it easier to support
2931 debugging of multiple languages in the future.
2933 GDB now uses a common structure for symbol information internally.
2934 Minimal symbols (derived from linkage symbols in object files), partial
2935 symbols (from a quick scan of debug information), and full symbols
2936 contain a common subset of information, making it easier to write
2937 shared code that handles any of them.
2939 * New command line options
2941 We now accept --silent as an alias for --quiet.
2945 The memory-mapped-malloc library is now licensed under the GNU Library
2946 General Public License.
2948 *** Changes in GDB-4.7:
2950 * Host/native/target split
2952 GDB has had some major internal surgery to untangle the support for
2953 hosts and remote targets. Now, when you configure GDB for a remote
2954 target, it will no longer load in all of the support for debugging
2955 local programs on the host. When fully completed and tested, this will
2956 ensure that arbitrary host/target combinations are possible.
2958 The primary conceptual shift is to separate the non-portable code in
2959 GDB into three categories. Host specific code is required any time GDB
2960 is compiled on that host, regardless of the target. Target specific
2961 code relates to the peculiarities of the target, but can be compiled on
2962 any host. Native specific code is everything else: it can only be
2963 built when the host and target are the same system. Child process
2964 handling and core file support are two common `native' examples.
2966 GDB's use of /proc for controlling Unix child processes is now cleaner.
2967 It has been split out into a single module under the `target_ops' vector,
2968 plus two native-dependent functions for each system that uses /proc.
2970 * New hosts supported
2972 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2973 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2974 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2976 * New targets supported
2978 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2979 68030 and CPU32 m68030-*-*, m68332-*-*
2981 * New native hosts supported
2983 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2984 (386bsd is not well tested yet)
2985 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2987 * New file formats supported
2989 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2990 supports reading of `a.out.adobe' object files, which are an a.out
2991 format extended with minimal information about multiple sections.
2995 `show copying' is the same as the old `info copying'.
2996 `show warranty' is the same as `info warrantee'.
2997 These were renamed for consistency. The old commands continue to work.
2999 `info handle' is a new alias for `info signals'.
3001 You can now define pre-command hooks, which attach arbitrary command
3002 scripts to any command. The commands in the hook will be executed
3003 prior to the user's command. You can also create a hook which will be
3004 executed whenever the program stops. See gdb.texinfo.
3008 We now deal with Cfront style name mangling, and can even extract type
3009 info from mangled symbols. GDB can automatically figure out which
3010 symbol mangling style your C++ compiler uses.
3012 Calling of methods and virtual functions has been improved as well.
3016 The crash that occured when debugging Sun Ansi-C compiled binaries is
3017 fixed. This was due to mishandling of the extra N_SO stabs output
3020 We also finally got Ultrix 4.2 running in house, and fixed core file
3021 support, with help from a dozen people on the net.
3023 John M. Farrell discovered that the reason that single-stepping was so
3024 slow on all of the Mips based platforms (primarily SGI and DEC) was
3025 that we were trying to demangle and lookup a symbol used for internal
3026 purposes on every instruction that was being stepped through. Changing
3027 the name of that symbol so that it couldn't be mistaken for a C++
3028 mangled symbol sped things up a great deal.
3030 Rich Pixley sped up symbol lookups in general by getting much smarter
3031 about when C++ symbol mangling is necessary. This should make symbol
3032 completion (TAB on the command line) much faster. It's not as fast as
3033 we'd like, but it's significantly faster than gdb-4.6.
3037 A new user controllable variable 'call_scratch_address' can
3038 specify the location of a scratch area to be used when GDB
3039 calls a function in the target. This is necessary because the
3040 usual method of putting the scratch area on the stack does not work
3041 in systems that have separate instruction and data spaces.
3043 We integrated changes to support the 29k UDI (Universal Debugger
3044 Interface), but discovered at the last minute that we didn't have all
3045 of the appropriate copyright paperwork. We are working with AMD to
3046 resolve this, and hope to have it available soon.
3050 We have sped up the remote serial line protocol, especially for targets
3051 with lots of registers. It now supports a new `expedited status' ('T')
3052 message which can be used in place of the existing 'S' status message.
3053 This allows the remote stub to send only the registers that GDB
3054 needs to make a quick decision about single-stepping or conditional
3055 breakpoints, eliminating the need to fetch the entire register set for
3056 each instruction being stepped through.
3058 The GDB remote serial protocol now implements a write-through cache for
3059 registers, only re-reading the registers if the target has run.
3061 There is also a new remote serial stub for SPARC processors. You can
3062 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3063 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3064 processor with a serial port.
3068 Configure.in files have become much easier to read and modify. A new
3069 `table driven' format makes it more obvious what configurations are
3070 supported, and what files each one uses.
3074 There is a new opcodes library which will eventually contain all of the
3075 disassembly routines and opcode tables. At present, it only contains
3076 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3077 disassembler (binutils/objdump) to share these routines.
3079 The libiberty library is now copylefted under the GNU Library General
3080 Public License. This allows more liberal use, and was done so libg++
3081 can use it. This makes no difference to GDB, since the Library License
3082 grants all the rights from the General Public License.
3086 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3087 reference to the stabs symbol info used by the debugger. It is (as far
3088 as we know) the only published document on this fascinating topic. We
3089 encourage you to read it, compare it to the stabs information on your
3090 system, and send improvements on the document in general (to
3091 bug-gdb@prep.ai.mit.edu).
3093 And, of course, many bugs have been fixed.
3096 *** Changes in GDB-4.6:
3098 * Better support for C++ function names
3100 GDB now accepts as input the "demangled form" of C++ overloaded function
3101 names and member function names, and can do command completion on such names
3102 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3103 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3104 Make use of command completion, it is your friend.
3106 GDB also now accepts a variety of C++ mangled symbol formats. They are
3107 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3108 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3109 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3110 for the list of formats.
3112 * G++ symbol mangling problem
3114 Recent versions of gcc have a bug in how they emit debugging information for
3115 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3116 directory) can be applied to gcc to fix the problem. Alternatively, if you
3117 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3118 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3119 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3122 * New 'maintenance' command
3124 All of the commands related to hacking GDB internals have been moved out of
3125 the main command set, and now live behind the 'maintenance' command. This
3126 can also be abbreviated as 'mt'. The following changes were made:
3128 dump-me -> maintenance dump-me
3129 info all-breakpoints -> maintenance info breakpoints
3130 printmsyms -> maintenance print msyms
3131 printobjfiles -> maintenance print objfiles
3132 printpsyms -> maintenance print psymbols
3133 printsyms -> maintenance print symbols
3135 The following commands are new:
3137 maintenance demangle Call internal GDB demangler routine to
3138 demangle a C++ link name and prints the result.
3139 maintenance print type Print a type chain for a given symbol
3141 * Change to .gdbinit file processing
3143 We now read the $HOME/.gdbinit file before processing the argv arguments
3144 (e.g. reading symbol files or core files). This allows global parameters to
3145 be set, which will apply during the symbol reading. The ./.gdbinit is still
3146 read after argv processing.
3148 * New hosts supported
3150 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3152 GNU/Linux support i386-unknown-linux or linux
3154 We are also including code to support the HP/PA running BSD and HPUX. This
3155 is almost guaranteed not to work, as we didn't have time to test or build it
3156 for this release. We are including it so that the more adventurous (or
3157 masochistic) of you can play with it. We also had major problems with the
3158 fact that the compiler that we got from HP doesn't support the -g option.
3161 * New targets supported
3163 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3165 * More smarts about finding #include files
3167 GDB now remembers the compilation directory for all include files, and for
3168 all files from which C is generated (like yacc and lex sources). This
3169 greatly improves GDB's ability to find yacc/lex sources, and include files,
3170 especially if you are debugging your program from a directory different from
3171 the one that contains your sources.
3173 We also fixed a bug which caused difficulty with listing and setting
3174 breakpoints in include files which contain C code. (In the past, you had to
3175 try twice in order to list an include file that you hadn't looked at before.)
3177 * Interesting infernals change
3179 GDB now deals with arbitrary numbers of sections, where the symbols for each
3180 section must be relocated relative to that section's landing place in the
3181 target's address space. This work was needed to support ELF with embedded
3182 stabs used by Solaris-2.0.
3184 * Bug fixes (of course!)
3186 There have been loads of fixes for the following things:
3187 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3188 i960, stabs, DOS(GO32), procfs, etc...
3190 See the ChangeLog for details.
3192 *** Changes in GDB-4.5:
3194 * New machines supported (host and target)
3196 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3198 SGI Irix-4.x mips-sgi-irix4 or iris4
3200 * New malloc package
3202 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3203 Mmalloc is capable of handling mutiple heaps of memory. It is also
3204 capable of saving a heap to a file, and then mapping it back in later.
3205 This can be used to greatly speedup the startup of GDB by using a
3206 pre-parsed symbol table which lives in a mmalloc managed heap. For
3207 more details, please read mmalloc/mmalloc.texi.
3211 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3212 'help info proc' for details.
3214 * MIPS ecoff symbol table format
3216 The code that reads MIPS symbol table format is now supported on all hosts.
3217 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3220 * File name changes for MS-DOS
3222 Many files in the config directories have been renamed to make it easier to
3223 support GDB on MS-DOSe systems (which have very restrictive file name
3224 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3225 environment) is close to working but has some remaining problems. Note
3226 that debugging of DOS programs is not supported, due to limitations
3227 in the ``operating system'', but it can be used to host cross-debugging.
3229 * Cross byte order fixes
3231 Many fixes have been made to support cross debugging of Sparc and MIPS
3232 targets from hosts whose byte order differs.
3234 * New -mapped and -readnow options
3236 If memory-mapped files are available on your system through the 'mmap'
3237 system call, you can use the -mapped option on the `file' or
3238 `symbol-file' commands to cause GDB to write the symbols from your
3239 program into a reusable file. If the program you are debugging is
3240 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3241 Future GDB debugging sessions will notice the presence of this file,
3242 and will quickly map in symbol information from it, rather than reading
3243 the symbol table from the executable program. Using the '-mapped'
3244 option in a GDB `file' or `symbol-file' command has the same effect as
3245 starting GDB with the '-mapped' command-line option.
3247 You can cause GDB to read the entire symbol table immediately by using
3248 the '-readnow' option with any of the commands that load symbol table
3249 information (or on the GDB command line). This makes the command
3250 slower, but makes future operations faster.
3252 The -mapped and -readnow options are typically combined in order to
3253 build a `fred.syms' file that contains complete symbol information.
3254 A simple GDB invocation to do nothing but build a `.syms' file for future
3257 gdb -batch -nx -mapped -readnow programname
3259 The `.syms' file is specific to the host machine on which GDB is run.
3260 It holds an exact image of GDB's internal symbol table. It cannot be
3261 shared across multiple host platforms.
3263 * longjmp() handling
3265 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3266 siglongjmp() without losing control. This feature has not yet been ported to
3267 all systems. It currently works on many 386 platforms, all MIPS-based
3268 platforms (SGI, DECstation, etc), and Sun3/4.
3272 Preliminary work has been put in to support the new Solaris OS from Sun. At
3273 this time, it can control and debug processes, but it is not capable of
3278 As always, many many bug fixes. The major areas were with g++, and mipsread.
3279 People using the MIPS-based platforms should experience fewer mysterious
3280 crashes and trashed symbol tables.
3282 *** Changes in GDB-4.4:
3284 * New machines supported (host and target)
3286 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3288 BSD Reno on Vax vax-dec-bsd
3289 Ultrix on Vax vax-dec-ultrix
3291 * New machines supported (target)
3293 AMD 29000 embedded, using EBMON a29k-none-none
3297 GDB continues to improve its handling of C++. `References' work better.
3298 The demangler has also been improved, and now deals with symbols mangled as
3299 per the Annotated C++ Reference Guide.
3301 GDB also now handles `stabs' symbol information embedded in MIPS
3302 `ecoff' symbol tables. Since the ecoff format was not easily
3303 extensible to handle new languages such as C++, this appeared to be a
3304 good way to put C++ debugging info into MIPS binaries. This option
3305 will be supported in the GNU C compiler, version 2, when it is
3308 * New features for SVR4
3310 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3311 shared libraries. Debugging dynamically linked programs should present
3312 only minor differences from debugging statically linked programs.
3314 The `info proc' command will print out information about any process
3315 on an SVR4 system (including the one you are debugging). At the moment,
3316 it prints the address mappings of the process.
3318 If you bring up GDB on another SVR4 system, please send mail to
3319 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3321 * Better dynamic linking support in SunOS
3323 Reading symbols from shared libraries which contain debugging symbols
3324 now works properly. However, there remain issues such as automatic
3325 skipping of `transfer vector' code during function calls, which
3326 make it harder to debug code in a shared library, than to debug the
3327 same code linked statically.
3331 GDB is now using the latest `getopt' routines from the FSF. This
3332 version accepts the -- prefix for options with long names. GDB will
3333 continue to accept the old forms (-option and +option) as well.
3334 Various single letter abbreviations for options have been explicity
3335 added to the option table so that they won't get overshadowed in the
3336 future by other options that begin with the same letter.
3340 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3341 Many assorted bugs have been handled. Many more remain to be handled.
3342 See the various ChangeLog files (primarily in gdb and bfd) for details.
3345 *** Changes in GDB-4.3:
3347 * New machines supported (host and target)
3349 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3350 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3351 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3353 * Almost SCO Unix support
3355 We had hoped to support:
3356 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3357 (except for core file support), but we discovered very late in the release
3358 that it has problems with process groups that render gdb unusable. Sorry
3359 about that. I encourage people to fix it and post the fixes.
3361 * Preliminary ELF and DWARF support
3363 GDB can read ELF object files on System V Release 4, and can handle
3364 debugging records for C, in DWARF format, in ELF files. This support
3365 is preliminary. If you bring up GDB on another SVR4 system, please
3366 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3371 GDB now uses the latest `readline' library. One user-visible change
3372 is that two tabs will list possible command completions, which previously
3373 required typing M-? (meta-question mark, or ESC ?).
3377 The `stepi' bug that many of you noticed has been squashed.
3378 Many bugs in C++ have been handled. Many more remain to be handled.
3379 See the various ChangeLog files (primarily in gdb and bfd) for details.
3381 * State of the MIPS world (in case you wondered):
3383 GDB can understand the symbol tables emitted by the compilers
3384 supplied by most vendors of MIPS-based machines, including DEC. These
3385 symbol tables are in a format that essentially nobody else uses.
3387 Some versions of gcc come with an assembler post-processor called
3388 mips-tfile. This program is required if you want to do source-level
3389 debugging of gcc-compiled programs. I believe FSF does not ship
3390 mips-tfile with gcc version 1, but it will eventually come with gcc
3393 Debugging of g++ output remains a problem. g++ version 1.xx does not
3394 really support it at all. (If you're lucky, you should be able to get
3395 line numbers and stack traces to work, but no parameters or local
3396 variables.) With some work it should be possible to improve the
3399 When gcc version 2 is released, you will have somewhat better luck.
3400 However, even then you will get confusing results for inheritance and
3403 We will eventually provide full debugging of g++ output on
3404 DECstations. This will probably involve some kind of stabs-in-ecoff
3405 encapulation, but the details have not been worked out yet.
3408 *** Changes in GDB-4.2:
3410 * Improved configuration
3412 Only one copy of `configure' exists now, and it is not self-modifying.
3413 Porting BFD is simpler.
3417 The `step' and `next' commands now only stop at the first instruction
3418 of a source line. This prevents the multiple stops that used to occur
3419 in switch statements, for-loops, etc. `Step' continues to stop if a
3420 function that has debugging information is called within the line.
3424 Lots of small bugs fixed. More remain.
3426 * New host supported (not target)
3428 Intel 386 PC clone running Mach i386-none-mach
3431 *** Changes in GDB-4.1:
3433 * Multiple source language support
3435 GDB now has internal scaffolding to handle several source languages.
3436 It determines the type of each source file from its filename extension,
3437 and will switch expression parsing and number formatting to match the
3438 language of the function in the currently selected stack frame.
3439 You can also specifically set the language to be used, with
3440 `set language c' or `set language modula-2'.
3444 GDB now has preliminary support for the GNU Modula-2 compiler,
3445 currently under development at the State University of New York at
3446 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3447 continue through the fall of 1991 and into 1992.
3449 Other Modula-2 compilers are currently not supported, and attempting to
3450 debug programs compiled with them will likely result in an error as the
3451 symbol table is read. Feel free to work on it, though!
3453 There are hooks in GDB for strict type checking and range checking,
3454 in the `Modula-2 philosophy', but they do not currently work.
3458 GDB can now write to executable and core files (e.g. patch
3459 a variable's value). You must turn this switch on, specify
3460 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3461 by assigning a new value to a variable. Modifications take
3464 * Automatic SunOS shared library reading
3466 When you run your program, GDB automatically determines where its
3467 shared libraries (if any) have been loaded, and reads their symbols.
3468 The `share' command is no longer needed. This also works when
3469 examining core files.
3473 You can specify the number of lines that the `list' command shows.
3476 * New machines supported (host and target)
3478 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3479 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3480 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3482 * New hosts supported (not targets)
3484 IBM RT/PC: romp-ibm-aix or rtpc
3486 * New targets supported (not hosts)
3488 AMD 29000 embedded with COFF a29k-none-coff
3489 AMD 29000 embedded with a.out a29k-none-aout
3490 Ultracomputer remote kernel debug a29k-nyu-kern
3492 * New remote interfaces
3498 *** Changes in GDB-4.0:
3502 Wide output is wrapped at good places to make the output more readable.
3504 Gdb now supports cross-debugging from a host machine of one type to a
3505 target machine of another type. Communication with the target system
3506 is over serial lines. The ``target'' command handles connecting to the
3507 remote system; the ``load'' command will download a program into the
3508 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3509 also supports debugging of realtime processes running under VxWorks,
3510 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3511 stub on the target system.
3513 New CPUs supported include the AMD 29000 and Intel 960.
3515 GDB now reads object files and symbol tables via a ``binary file''
3516 library, which allows a single copy of GDB to debug programs of multiple
3517 object file types such as a.out and coff.
3519 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3520 refcard.dvi and refcard.ps are available to format it).
3523 * Control-Variable user interface simplified
3525 All variables that control the operation of the debugger can be set
3526 by the ``set'' command, and displayed by the ``show'' command.
3528 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3529 ``Show prompt'' produces the response:
3530 Gdb's prompt is new-gdb=>.
3532 What follows are the NEW set commands. The command ``help set'' will
3533 print a complete list of old and new set commands. ``help set FOO''
3534 will give a longer description of the variable FOO. ``show'' will show
3535 all of the variable descriptions and their current settings.
3537 confirm on/off: Enables warning questions for operations that are
3538 hard to recover from, e.g. rerunning the program while
3539 it is already running. Default is ON.
3541 editing on/off: Enables EMACS style command line editing
3542 of input. Previous lines can be recalled with
3543 control-P, the current line can be edited with control-B,
3544 you can search for commands with control-R, etc.
3547 history filename NAME: NAME is where the gdb command history
3548 will be stored. The default is .gdb_history,
3549 or the value of the environment variable
3552 history size N: The size, in commands, of the command history. The
3553 default is 256, or the value of the environment variable
3556 history save on/off: If this value is set to ON, the history file will
3557 be saved after exiting gdb. If set to OFF, the
3558 file will not be saved. The default is OFF.
3560 history expansion on/off: If this value is set to ON, then csh-like
3561 history expansion will be performed on
3562 command line input. The default is OFF.
3564 radix N: Sets the default radix for input and output. It can be set
3565 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3566 in the current radix, so "set radix 10" is always a no-op.
3568 height N: This integer value is the number of lines on a page. Default
3569 is 24, the current `stty rows'' setting, or the ``li#''
3570 setting from the termcap entry matching the environment
3573 width N: This integer value is the number of characters on a line.
3574 Default is 80, the current `stty cols'' setting, or the ``co#''
3575 setting from the termcap entry matching the environment
3578 Note: ``set screensize'' is obsolete. Use ``set height'' and
3579 ``set width'' instead.
3581 print address on/off: Print memory addresses in various command displays,
3582 such as stack traces and structure values. Gdb looks
3583 more ``symbolic'' if you turn this off; it looks more
3584 ``machine level'' with it on. Default is ON.
3586 print array on/off: Prettyprint arrays. New convenient format! Default
3589 print demangle on/off: Print C++ symbols in "source" form if on,
3592 print asm-demangle on/off: Same, for assembler level printouts
3595 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3598 * Support for Epoch Environment.
3600 The epoch environment is a version of Emacs v18 with windowing. One
3601 new command, ``inspect'', is identical to ``print'', except that if you
3602 are running in the epoch environment, the value is printed in its own
3606 * Support for Shared Libraries
3608 GDB can now debug programs and core files that use SunOS shared libraries.
3609 Symbols from a shared library cannot be referenced
3610 before the shared library has been linked with the program (this
3611 happens after you type ``run'' and before the function main() is entered).
3612 At any time after this linking (including when examining core files
3613 from dynamically linked programs), gdb reads the symbols from each
3614 shared library when you type the ``sharedlibrary'' command.
3615 It can be abbreviated ``share''.
3617 sharedlibrary REGEXP: Load shared object library symbols for files
3618 matching a unix regular expression. No argument
3619 indicates to load symbols for all shared libraries.
3621 info sharedlibrary: Status of loaded shared libraries.
3626 A watchpoint stops execution of a program whenever the value of an
3627 expression changes. Checking for this slows down execution
3628 tremendously whenever you are in the scope of the expression, but is
3629 quite useful for catching tough ``bit-spreader'' or pointer misuse
3630 problems. Some machines such as the 386 have hardware for doing this
3631 more quickly, and future versions of gdb will use this hardware.
3633 watch EXP: Set a watchpoint (breakpoint) for an expression.
3635 info watchpoints: Information about your watchpoints.
3637 delete N: Deletes watchpoint number N (same as breakpoints).
3638 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3639 enable N: Re-enables watchpoint number N (same as breakpoints).
3642 * C++ multiple inheritance
3644 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3647 * C++ exception handling
3649 Gdb now supports limited C++ exception handling. Besides the existing
3650 ability to breakpoint on an exception handler, gdb can breakpoint on
3651 the raising of an exception (before the stack is peeled back to the
3654 catch FOO: If there is a FOO exception handler in the dynamic scope,
3655 set a breakpoint to catch exceptions which may be raised there.
3656 Multiple exceptions (``catch foo bar baz'') may be caught.
3658 info catch: Lists all exceptions which may be caught in the
3659 current stack frame.
3662 * Minor command changes
3664 The command ``call func (arg, arg, ...)'' now acts like the print
3665 command, except it does not print or save a value if the function's result
3666 is void. This is similar to dbx usage.
3668 The ``up'' and ``down'' commands now always print the frame they end up
3669 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3670 frames without printing.
3672 * New directory command
3674 'dir' now adds directories to the FRONT of the source search path.
3675 The path starts off empty. Source files that contain debug information
3676 about the directory in which they were compiled can be found even
3677 with an empty path; Sun CC and GCC include this information. If GDB can't
3678 find your source file in the current directory, type "dir .".
3680 * Configuring GDB for compilation
3682 For normal use, type ``./configure host''. See README or gdb.texinfo
3685 GDB now handles cross debugging. If you are remotely debugging between
3686 two different machines, type ``./configure host -target=targ''.
3687 Host is the machine where GDB will run; targ is the machine
3688 where the program that you are debugging will run.