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 sh calling-convention
267 show sh calling-convention
268 Control the calling convention used when calling SH target functions.
270 set print symbol-loading
271 show print symbol-loading
272 Control printing of symbol loading messages.
276 Control display of timestamps with GDB debugging output.
278 set disassemble-next-line
279 show disassemble-next-line
280 Control display of disassembled source lines or instructions when
283 set remote noack-packet
284 show remote noack-packet
285 Set/show the use of remote protocol QStartNoAckMode packet. See above
286 under "New remote packets."
288 set remote query-attached-packet
289 show remote query-attached-packet
290 Control use of remote protocol `qAttached' (query-attached) packet.
292 set remote read-siginfo-object
293 show remote read-siginfo-object
294 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
297 set remote write-siginfo-object
298 show remote write-siginfo-object
299 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
302 set displaced-stepping
303 show displaced-stepping
304 Control displaced stepping mode. Displaced stepping is a way to
305 single-step over breakpoints without removing them from the debuggee.
306 Also known as "out-of-line single-stepping".
310 Control display of debugging info for displaced stepping.
312 maint set internal-error
313 maint show internal-error
314 Control what GDB does when an internal error is detected.
316 maint set internal-warning
317 maint show internal-warning
318 Control what GDB does when an internal warning is detected.
323 Use a wrapper program to launch programs for debugging.
325 set multiple-symbols (all|ask|cancel)
326 show multiple-symbols
327 The value of this variable can be changed to adjust the debugger behavior
328 when an expression or a breakpoint location contains an ambiguous symbol
329 name (an overloaded function name, for instance).
331 set breakpoint always-inserted
332 show breakpoint always-inserted
333 Keep breakpoints always inserted in the target, as opposed to inserting
334 them when resuming the target, and removing them when the target stops.
335 This option can improve debugger performance on slow remote targets.
337 set arm fallback-mode (arm|thumb|auto)
338 show arm fallback-mode
339 set arm force-mode (arm|thumb|auto)
341 These commands control how ARM GDB determines whether instructions
342 are ARM or Thumb. The default for both settings is auto, which uses
343 the current CPSR value for instructions without symbols; previous
344 versions of GDB behaved as if "set arm fallback-mode arm".
346 set disable-randomization
347 show disable-randomization
348 Standalone programs run with the virtual address space randomization enabled
349 by default on some platforms. This option keeps the addresses stable across
350 multiple debugging sessions.
354 Control whether other threads are stopped or not when some thread hits
359 Requests that asynchronous execution is enabled in the target, if available.
360 In this case, it's possible to resume target in the background, and interact
361 with GDB while the target is running. "show target-async" displays the
362 current state of asynchronous execution of the target.
364 set target-wide-charset
365 show target-wide-charset
366 The target-wide-charset is the name of the character set that GDB
367 uses when printing characters whose type is wchar_t.
369 set tcp auto-retry (on|off)
371 set tcp connect-timeout
372 show tcp connect-timeout
373 These commands allow GDB to retry failed TCP connections to a remote stub
374 with a specified timeout period; this is useful if the stub is launched
375 in parallel with GDB but may not be ready to accept connections immediately.
377 set libthread-db-search-path
378 show libthread-db-search-path
379 Control list of directories which GDB will search for appropriate
382 set schedule-multiple (on|off)
383 show schedule-multiple
384 Allow GDB to resume all threads of all processes or only threads of
390 For program forks, this is replaced by the new more generic `info
391 inferiors' command. To list checkpoints, you can still use the
392 `info checkpoints' command, which was an alias for the `info forks'
396 Replaced by the new `inferior' command. To switch between
397 checkpoints, you can still use the `restart' command, which was an
398 alias for the `fork' command.
401 This is removed, since some targets don't have a notion of
402 processes. To switch between processes, you can still use the
403 `inferior' command using GDB's own inferior number.
406 For program forks, this is replaced by the new more generic `kill
407 inferior' command. To delete a checkpoint, you can still use the
408 `delete checkpoint' command, which was an alias for the `delete
412 For program forks, this is replaced by the new more generic `detach
413 inferior' command. To detach a checkpoint, you can still use the
414 `detach checkpoint' command, which was an alias for the `detach
417 * New native configurations
419 x86/x86_64 Darwin i[34567]86-*-darwin*
421 x86_64 MinGW x86_64-*-mingw*
425 Lattice Mico32 lm32-*
426 x86 DICOS i[34567]86-*-dicos*
427 x86_64 DICOS x86_64-*-dicos*
429 * The GDB remote stub, gdbserver, now supports x86 Windows CE
430 (mingw32ce) debugging.
436 These commands were actually not implemented on any target.
438 *** Changes in GDB 6.8
440 * New native configurations
442 NetBSD/hppa hppa*-*netbsd*
443 Xtensa GNU/Linux xtensa*-*-linux*
447 NetBSD/hppa hppa*-*-netbsd*
448 Xtensa GNU/Lunux xtensa*-*-linux*
450 * Change in command line behavior -- corefiles vs. process ids.
452 When the '-p NUMBER' or '--pid NUMBER' options are used, and
453 attaching to process NUMBER fails, GDB no longer attempts to open a
454 core file named NUMBER. Attaching to a program using the -c option
455 is no longer supported. Instead, use the '-p' or '--pid' options.
457 * GDB can now be built as a native debugger for debugging Windows x86
458 (mingw32) Portable Executable (PE) programs.
460 * Pending breakpoints no longer change their number when their address
463 * GDB now supports breakpoints with multiple locations,
464 including breakpoints on C++ constructors, inside C++ templates,
465 and in inlined functions.
467 * GDB's ability to debug optimized code has been improved. GDB more
468 accurately identifies function bodies and lexical blocks that occupy
469 more than one contiguous range of addresses.
471 * Target descriptions can now describe registers for PowerPC.
473 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
474 registers on PowerPC targets.
476 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
477 targets even when the libthread_db library is not available.
479 * The GDB remote stub, gdbserver, now supports the new file transfer
480 commands (remote put, remote get, and remote delete).
482 * The GDB remote stub, gdbserver, now supports run and attach in
483 extended-remote mode.
485 * hppa*64*-*-hpux11* target broken
486 The debugger is unable to start a program and fails with the following
487 error: "Error trying to get information about dynamic linker".
488 The gdb-6.7 release is also affected.
490 * GDB now supports the --enable-targets= configure option to allow
491 building a single GDB executable that supports multiple remote
492 target architectures.
494 * GDB now supports debugging C and C++ programs which use the
495 Decimal Floating Point extension. In addition, the PowerPC target
496 now has a set of pseudo-registers to inspect decimal float values
497 stored in two consecutive float registers.
499 * The -break-insert MI command can optionally create pending
502 * Improved support for debugging Ada
503 Many improvements to the Ada language support have been made. These
505 - Better support for Ada2005 interface types
506 - Improved handling of arrays and slices in general
507 - Better support for Taft-amendment types
508 - The '{type} ADDRESS' expression is now allowed on the left hand-side
510 - Improved command completion in Ada
513 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
518 set print frame-arguments (all|scalars|none)
519 show print frame-arguments
520 The value of this variable can be changed to control which argument
521 values should be printed by the debugger when displaying a frame.
526 Transfer files to and from a remote target, and delete remote files.
533 Transfer files to and from a remote target, and delete remote files.
542 Open, close, read, write, and delete files on the remote system.
545 Attach to an existing process on the remote system, in extended-remote
549 Run a new process on the remote system, in extended-remote mode.
551 *** Changes in GDB 6.7
553 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
554 bfd, libiberty and opcodes, as revealed by static analysis donated by
555 Coverity, Inc. (http://scan.coverity.com).
557 * When looking up multiply-defined global symbols, GDB will now prefer the
558 symbol definition in the current shared library if it was built using the
559 -Bsymbolic linker option.
561 * When the Text User Interface (TUI) is not configured, GDB will now
562 recognize the -tui command-line option and print a message that the TUI
565 * The GDB remote stub, gdbserver, now has lower overhead for high
566 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
568 * GDB for MIPS targets now autodetects whether a remote target provides
569 32-bit or 64-bit register values.
571 * Support for C++ member pointers has been improved.
573 * GDB now understands XML target descriptions, which specify the
574 target's overall architecture. GDB can read a description from
575 a local file or over the remote serial protocol.
577 * Vectors of single-byte data use a new integer type which is not
578 automatically displayed as character or string data.
580 * The /s format now works with the print command. It displays
581 arrays of single-byte integers and pointers to single-byte integers
584 * Target descriptions can now describe target-specific registers,
585 for architectures which have implemented the support (currently
586 only ARM, M68K, and MIPS).
588 * GDB and the GDB remote stub, gdbserver, now support the XScale
591 * The GDB remote stub, gdbserver, has been updated to support
592 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
593 has been rewritten to use the standard GDB remote protocol.
595 * GDB can now step into C++ functions which are called through thunks.
597 * GDB for the Cell/B.E. SPU now supports overlay debugging.
599 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
600 layout. It also supports a TextSeg= and DataSeg= response when only
601 segment base addresses (rather than offsets) are available.
603 * The /i format now outputs any trailing branch delay slot instructions
604 immediately following the last instruction within the count specified.
606 * The GDB remote protocol "T" stop reply packet now supports a
607 "library" response. Combined with the new "qXfer:libraries:read"
608 packet, this response allows GDB to debug shared libraries on targets
609 where the operating system manages the list of loaded libraries (e.g.
610 Windows and SymbianOS).
612 * The GDB remote stub, gdbserver, now supports dynamic link libraries
613 (DLLs) on Windows and Windows CE targets.
615 * GDB now supports a faster verification that a .debug file matches its binary
616 according to its build-id signature, if the signature is present.
622 Enable or disable hardware flow control (RTS/CTS) on the serial port
623 when debugging using remote targets.
625 set mem inaccessible-by-default
626 show mem inaccessible-by-default
627 If the target supplies a memory map, for instance via the remote
628 protocol's "qXfer:memory-map:read" packet, setting this variable
629 prevents GDB from accessing memory outside the memory map. This
630 is useful for targets with memory mapped registers or which react
631 badly to accesses of unmapped address space.
633 set breakpoint auto-hw
634 show breakpoint auto-hw
635 If the target supplies a memory map, for instance via the remote
636 protocol's "qXfer:memory-map:read" packet, setting this variable
637 lets GDB use hardware breakpoints automatically for memory regions
638 where it can not use software breakpoints. This covers both the
639 "break" command and internal breakpoints used for other commands
640 including "next" and "finish".
643 catch exception unhandled
644 Stop the program execution when Ada exceptions are raised.
647 Stop the program execution when an Ada assertion failed.
651 Set an alternate system root for target files. This is a more
652 general version of "set solib-absolute-prefix", which is now
653 an alias to "set sysroot".
656 Provide extended SPU facility status information. This set of
657 commands is available only when debugging the Cell/B.E. SPU
660 * New native configurations
662 OpenBSD/sh sh*-*openbsd*
667 Use the specified local file as an XML target description, and do
668 not query the target for its built-in description.
672 OpenBSD/sh sh*-*-openbsd*
673 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
674 Toshiba Media Processor mep-elf
679 Ignore the specified signals; pass them directly to the debugged program
680 without stopping other threads or reporting them to GDB.
683 Read an XML target description from the target, which describes its
688 Read or write contents of an spufs file on the target system. These
689 packets are available only on the Cell/B.E. SPU architecture.
691 qXfer:libraries:read:
692 Report the loaded shared libraries. Combined with new "T" packet
693 response, this packet allows GDB to debug shared libraries on
694 targets where the operating system manages the list of loaded
695 libraries (e.g. Windows and SymbianOS).
699 Support for these obsolete configurations has been removed.
708 i[34567]86-*-netware*
709 i[34567]86-*-sco3.2v5*
710 i[34567]86-*-sco3.2v4*
712 i[34567]86-*-sysv4.2*
715 i[34567]86-*-unixware2*
716 i[34567]86-*-unixware*
725 * Other removed features
732 Various m68k-only ROM monitors.
739 Various Renesas ROM monitors and debugging interfaces for SH and
744 Support for a Macraigor serial interface to on-chip debugging.
745 GDB does not directly support the newer parallel or USB
750 A debug information format. The predecessor to DWARF 2 and
751 DWARF 3, which are still supported.
753 Support for the HP aCC compiler on HP-UX/PA-RISC
755 SOM-encapsulated symbolic debugging information, automatic
756 invocation of pxdb, and the aCC custom C++ ABI. This does not
757 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
758 with aCC can still be debugged on an assembly level.
762 A MIPS-specific format used to describe stack frame layout
763 in debugging information.
767 GDB could work with an older version of Guile to debug
768 the interpreter and Scheme programs running in it.
770 set mips stack-arg-size
771 set mips saved-gpreg-size
773 Use "set mips abi" to control parameter passing for MIPS.
775 *** Changes in GDB 6.6
780 Cell Broadband Engine SPU spu-elf
782 * GDB can now be configured as a cross-debugger targeting native Windows
783 (mingw32) or Cygwin. It can communicate with a remote debugging stub
784 running on a Windows system over TCP/IP to debug Windows programs.
786 * The GDB remote stub, gdbserver, has been updated to support Windows and
787 Cygwin debugging. Both single-threaded and multi-threaded programs are
790 * The "set trust-readonly-sections" command works again. This command was
791 broken in GDB 6.3, 6.4, and 6.5.
793 * The "load" command now supports writing to flash memory, if the remote
794 stub provides the required support.
796 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
797 longer requires symbolic debug information (e.g. DWARF-2).
802 unset substitute-path
804 Manage a list of substitution rules that GDB uses to rewrite the name
805 of the directories where the sources are located. This can be useful
806 for instance when the sources were moved to a different location
807 between compilation and debugging.
811 Print each CLI command as it is executed. Each command is prefixed with
812 a number of `+' symbols representing the nesting depth.
813 The source command now has a `-v' option to enable the same feature.
817 The ARM Demon monitor support (RDP protocol, "target rdp").
819 Kernel Object Display, an embedded debugging feature which only worked with
820 an obsolete version of Cisco IOS.
822 The 'set download-write-size' and 'show download-write-size' commands.
827 Tell a stub about GDB client features, and request remote target features.
828 The first feature implemented is PacketSize, which allows the target to
829 specify the size of packets it can handle - to minimize the number of
830 packets required and improve performance when connected to a remote
834 Fetch an OS auxilliary vector from the remote stub. This packet is a
835 more efficient replacement for qPart:auxv:read.
837 qXfer:memory-map:read:
838 Fetch a memory map from the remote stub, including information about
839 RAM, ROM, and flash memory devices.
844 Erase and program a flash memory device.
846 * Removed remote packets
849 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
850 used it, and only gdbserver implemented it.
852 *** Changes in GDB 6.5
856 Renesas M32C/M16C m32c-elf
858 Morpho Technologies ms1 ms1-elf
862 init-if-undefined Initialize a convenience variable, but
863 only if it doesn't already have a value.
865 The following commands are presently only implemented for native GNU/Linux:
867 checkpoint Save a snapshot of the program state.
869 restart <n> Return the program state to a
870 previously saved state.
872 info checkpoints List currently saved checkpoints.
874 delete-checkpoint <n> Delete a previously saved checkpoint.
876 set|show detach-on-fork Tell gdb whether to detach from a newly
877 forked process, or to keep debugging it.
879 info forks List forks of the user program that
880 are available to be debugged.
882 fork <n> Switch to debugging one of several
883 forks of the user program that are
884 available to be debugged.
886 delete-fork <n> Delete a fork from the list of forks
887 that are available to be debugged (and
888 kill the forked process).
890 detach-fork <n> Delete a fork from the list of forks
891 that are available to be debugged (and
892 allow the process to continue).
896 Morpho Technologies ms2 ms1-elf
898 * Improved Windows host support
900 GDB now builds as a cross debugger hosted on i686-mingw32, including
901 native console support, and remote communications using either
902 network sockets or serial ports.
904 * Improved Modula-2 language support
906 GDB can now print most types in the Modula-2 syntax. This includes:
907 basic types, set types, record types, enumerated types, range types,
908 pointer types and ARRAY types. Procedure var parameters are correctly
909 printed and hexadecimal addresses and character constants are also
910 written in the Modula-2 syntax. Best results can be obtained by using
911 GNU Modula-2 together with the -gdwarf-2 command line option.
915 The ARM rdi-share module.
917 The Netware NLM debug server.
919 *** Changes in GDB 6.4
921 * New native configurations
923 OpenBSD/arm arm*-*-openbsd*
924 OpenBSD/mips64 mips64-*-openbsd*
928 Morpho Technologies ms1 ms1-elf
930 * New command line options
932 --batch-silent As for --batch, but totally silent.
933 --return-child-result The debugger will exist with the same value
934 the child (debugged) program exited with.
935 --eval-command COMMAND, -ex COMMAND
936 Execute a single GDB CLI command. This may be
937 specified multiple times and in conjunction
938 with the --command (-x) option.
940 * Deprecated commands removed
942 The following commands, that were deprecated in 2000, have been
946 set|show arm disassembly-flavor set|show arm disassembler
947 othernames set arm disassembler
948 set|show remotedebug set|show debug remote
949 set|show archdebug set|show debug arch
950 set|show eventdebug set|show debug event
953 * New BSD user-level threads support
955 It is now possible to debug programs using the user-level threads
956 library on OpenBSD and FreeBSD. Currently supported (target)
959 FreeBSD/amd64 x86_64-*-freebsd*
960 FreeBSD/i386 i386-*-freebsd*
961 OpenBSD/i386 i386-*-openbsd*
963 Note that the new kernel threads libraries introduced in FreeBSD 5.x
964 are not yet supported.
966 * New support for Matsushita MN10300 w/sim added
967 (Work in progress). mn10300-elf.
969 * REMOVED configurations and files
971 VxWorks and the XDR protocol *-*-vxworks
972 Motorola MCORE mcore-*-*
973 National Semiconductor NS32000 ns32k-*-*
975 * New "set print array-indexes" command
977 After turning this setting "on", GDB prints the index of each element
978 when displaying arrays. The default is "off" to preserve the previous
981 * VAX floating point support
983 GDB now supports the not-quite-ieee VAX F and D floating point formats.
985 * User-defined command support
987 In addition to using $arg0..$arg9 for argument passing, it is now possible
988 to use $argc to determine now many arguments have been passed. See the
989 section on user-defined commands in the user manual for more information.
991 *** Changes in GDB 6.3:
993 * New command line option
995 GDB now accepts -l followed by a number to set the timeout for remote
998 * GDB works with GCC -feliminate-dwarf2-dups
1000 GDB now supports a more compact representation of DWARF-2 debug
1001 information using DW_FORM_ref_addr references. These are produced
1002 by GCC with the option -feliminate-dwarf2-dups and also by some
1003 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1004 to use -feliminate-dwarf2-dups.
1006 * Internationalization
1008 When supported by the host system, GDB will be built with
1009 internationalization (libintl). The task of marking up the sources is
1010 continued, we're looking forward to our first translation.
1014 Initial support for debugging programs compiled with the GNAT
1015 implementation of the Ada programming language has been integrated
1016 into GDB. In this release, support is limited to expression evaluation.
1018 * New native configurations
1020 GNU/Linux/m32r m32r-*-linux-gnu
1024 GDB's remote protocol now includes support for the 'p' packet. This
1025 packet is used to fetch individual registers from a remote inferior.
1027 * END-OF-LIFE registers[] compatibility module
1029 GDB's internal register infrastructure has been completely rewritten.
1030 The new infrastructure making possible the implementation of key new
1031 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1034 GDB 6.3 will be the last release to include the the registers[]
1035 compatibility module that allowed out-of-date configurations to
1036 continue to work. This change directly impacts the following
1046 powerpc bdm protocol
1048 Unless there is activity to revive these configurations, they will be
1049 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1051 * OBSOLETE configurations and files
1053 Configurations that have been declared obsolete in this release have
1054 been commented out. Unless there is activity to revive these
1055 configurations, the next release of GDB will have their sources
1056 permanently REMOVED.
1065 *** Changes in GDB 6.2.1:
1067 * MIPS `break main; run' gave an heuristic-fence-post warning
1069 When attempting to run even a simple program, a warning about
1070 heuristic-fence-post being hit would be reported. This problem has
1073 * MIPS IRIX 'long double' crashed GDB
1075 When examining a long double variable, GDB would get a segmentation
1076 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1077 IRIX long double values).
1081 A bug in the VAX stack code was causing problems with the "next"
1082 command. This problem has been fixed.
1084 *** Changes in GDB 6.2:
1086 * Fix for ``many threads''
1088 On GNU/Linux systems that use the NPTL threads library, a program
1089 rapidly creating and deleting threads would confuse GDB leading to the
1092 ptrace: No such process.
1093 thread_db_get_info: cannot get thread info: generic error
1095 This problem has been fixed.
1097 * "-async" and "-noasync" options removed.
1099 Support for the broken "-noasync" option has been removed (it caused
1102 * New ``start'' command.
1104 This command runs the program until the begining of the main procedure.
1106 * New BSD Kernel Data Access Library (libkvm) interface
1108 Using ``target kvm'' it is now possible to debug kernel core dumps and
1109 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1110 platforms. Currently supported (native-only) configurations are:
1112 FreeBSD/amd64 x86_64-*-freebsd*
1113 FreeBSD/i386 i?86-*-freebsd*
1114 NetBSD/i386 i?86-*-netbsd*
1115 NetBSD/m68k m68*-*-netbsd*
1116 NetBSD/sparc sparc-*-netbsd*
1117 OpenBSD/amd64 x86_64-*-openbsd*
1118 OpenBSD/i386 i?86-*-openbsd*
1119 OpenBSD/m68k m68*-openbsd*
1120 OpenBSD/sparc sparc-*-openbsd*
1122 * Signal trampoline code overhauled
1124 Many generic problems with GDB's signal handling code have been fixed.
1125 These include: backtraces through non-contiguous stacks; recognition
1126 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1127 call; backtrace through a signal trampoline; step into and out of
1128 signal handlers; and single-stepping in the signal trampoline.
1130 Please note that kernel bugs are a limiting factor here. These
1131 features have been shown to work on an s390 GNU/Linux system that
1132 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1134 * Cygwin support for DWARF 2 added.
1136 * New native configurations
1138 GNU/Linux/hppa hppa*-*-linux*
1139 OpenBSD/hppa hppa*-*-openbsd*
1140 OpenBSD/m68k m68*-*-openbsd*
1141 OpenBSD/m88k m88*-*-openbsd*
1142 OpenBSD/powerpc powerpc-*-openbsd*
1143 NetBSD/vax vax-*-netbsd*
1144 OpenBSD/vax vax-*-openbsd*
1146 * END-OF-LIFE frame compatibility module
1148 GDB's internal frame infrastructure has been completely rewritten.
1149 The new infrastructure making it possible to support key new features
1150 including DWARF 2 Call Frame Information. To aid in the task of
1151 migrating old configurations to this new infrastructure, a
1152 compatibility module, that allowed old configurations to continue to
1153 work, was also included.
1155 GDB 6.2 will be the last release to include this frame compatibility
1156 module. This change directly impacts the following configurations:
1166 Unless there is activity to revive these configurations, they will be
1167 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1169 * REMOVED configurations and files
1171 Sun 3, running SunOS 3 m68*-*-sunos3*
1172 Sun 3, running SunOS 4 m68*-*-sunos4*
1173 Sun 2, running SunOS 3 m68000-*-sunos3*
1174 Sun 2, running SunOS 4 m68000-*-sunos4*
1175 Motorola 680x0 running LynxOS m68*-*-lynxos*
1176 AT&T 3b1/Unix pc m68*-att-*
1177 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1178 decstation mips-dec-* mips-little-*
1179 riscos mips-*-riscos* mips-*-sysv*
1180 sonymips mips-sony-*
1181 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1183 *** Changes in GDB 6.1.1:
1185 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1187 The TUI (Text-mode User Interface) is now built as part of a default
1188 GDB configuration. It is enabled by either selecting the TUI with the
1189 command line option "-i=tui" or by running the separate "gdbtui"
1190 program. For more information on the TUI, see the manual "Debugging
1193 * Pending breakpoint support (also included in GDB 6.1)
1195 Support has been added to allow you to specify breakpoints in shared
1196 libraries that have not yet been loaded. If a breakpoint location
1197 cannot be found, and the "breakpoint pending" option is set to auto,
1198 GDB queries you if you wish to make the breakpoint pending on a future
1199 shared-library load. If and when GDB resolves the breakpoint symbol,
1200 the pending breakpoint is removed as one or more regular breakpoints
1203 Pending breakpoints are very useful for GCJ Java debugging.
1205 * Fixed ISO-C build problems
1207 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1208 non ISO-C code that stopped them being built using a more strict ISO-C
1209 compiler (e.g., IBM's C compiler).
1211 * Fixed build problem on IRIX 5
1213 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1214 wasn't able to compile compile on an IRIX 5 system.
1216 * Added execute permission to gdb/gdbserver/configure
1218 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1219 permission. This bug would cause configure to fail on a number of
1220 systems (Solaris, IRIX). Ref: server/519.
1222 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1224 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1225 has been updated to use constant array sizes.
1227 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1229 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1230 its generated DWARF Call Frame Info. This encoding was causing GDB to
1231 panic, that panic has been fixed. Ref: gdb/1628.
1233 * Fixed a problem when examining parameters in shared library code.
1235 When examining parameters in optimized shared library code generated
1236 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1237 not available''. GDB now correctly displays the variable's value.
1239 *** Changes in GDB 6.1:
1241 * Removed --with-mmalloc
1243 Support for the mmalloc memory manager has been removed, as it
1244 conflicted with the internal gdb byte cache.
1246 * Changes in AMD64 configurations
1248 The AMD64 target now includes the %cs and %ss registers. As a result
1249 the AMD64 remote protocol has changed; this affects the floating-point
1250 and SSE registers. If you rely on those registers for your debugging,
1251 you should upgrade gdbserver on the remote side.
1253 * Revised SPARC target
1255 The SPARC target has been completely revised, incorporating the
1256 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1257 support for LynxOS and SunOS 4 has been dropped. Calling functions
1258 from within GDB on operating systems with a non-executable stack
1259 (Solaris, OpenBSD) now works.
1263 GDB has a new C++ demangler which does a better job on the mangled
1264 names generated by current versions of g++. It also runs faster, so
1265 with this and other changes gdb should now start faster on large C++
1268 * DWARF 2 Location Expressions
1270 GDB support for location expressions has been extended to support function
1271 arguments and frame bases. Older versions of GDB could crash when they
1274 * C++ nested types and namespaces
1276 GDB's support for nested types and namespaces in C++ has been
1277 improved, especially if you use the DWARF 2 debugging format. (This
1278 is the default for recent versions of GCC on most platforms.)
1279 Specifically, if you have a class "Inner" defined within a class or
1280 namespace "Outer", then GDB realizes that the class's name is
1281 "Outer::Inner", not simply "Inner". This should greatly reduce the
1282 frequency of complaints about not finding RTTI symbols. In addition,
1283 if you are stopped at inside of a function defined within a namespace,
1284 GDB modifies its name lookup accordingly.
1286 * New native configurations
1288 NetBSD/amd64 x86_64-*-netbsd*
1289 OpenBSD/amd64 x86_64-*-openbsd*
1290 OpenBSD/alpha alpha*-*-openbsd*
1291 OpenBSD/sparc sparc-*-openbsd*
1292 OpenBSD/sparc64 sparc64-*-openbsd*
1294 * New debugging protocols
1296 M32R with SDI protocol m32r-*-elf*
1298 * "set prompt-escape-char" command deleted.
1300 The command "set prompt-escape-char" has been deleted. This command,
1301 and its very obscure effet on GDB's prompt, was never documented,
1302 tested, nor mentioned in the NEWS file.
1304 * OBSOLETE configurations and files
1306 Configurations that have been declared obsolete in this release have
1307 been commented out. Unless there is activity to revive these
1308 configurations, the next release of GDB will have their sources
1309 permanently REMOVED.
1311 Sun 3, running SunOS 3 m68*-*-sunos3*
1312 Sun 3, running SunOS 4 m68*-*-sunos4*
1313 Sun 2, running SunOS 3 m68000-*-sunos3*
1314 Sun 2, running SunOS 4 m68000-*-sunos4*
1315 Motorola 680x0 running LynxOS m68*-*-lynxos*
1316 AT&T 3b1/Unix pc m68*-att-*
1317 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1318 decstation mips-dec-* mips-little-*
1319 riscos mips-*-riscos* mips-*-sysv*
1320 sonymips mips-sony-*
1321 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1323 * REMOVED configurations and files
1325 SGI Irix-4.x mips-sgi-irix4 or iris4
1326 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1327 Z8000 simulator z8k-zilog-none or z8ksim
1328 Matsushita MN10200 w/simulator mn10200-*-*
1329 H8/500 simulator h8500-hitachi-hms or h8500hms
1330 HP/PA running BSD hppa*-*-bsd*
1331 HP/PA running OSF/1 hppa*-*-osf*
1332 HP/PA Pro target hppa*-*-pro*
1333 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1334 386BSD i[3456]86-*-bsd*
1335 Sequent family i[3456]86-sequent-sysv4*
1336 i[3456]86-sequent-sysv*
1337 i[3456]86-sequent-bsd*
1338 SPARC running LynxOS sparc-*-lynxos*
1339 SPARC running SunOS 4 sparc-*-sunos4*
1340 Tsqware Sparclet sparclet-*-*
1341 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1343 *** Changes in GDB 6.0:
1347 Support for debugging the Objective-C programming language has been
1348 integrated into GDB.
1350 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1352 DWARF 2's Call Frame Information makes available compiler generated
1353 information that more exactly describes the program's run-time stack.
1354 By using this information, GDB is able to provide more robust stack
1357 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1358 have been updated to use a new backtrace mechanism which includes
1359 DWARF 2 CFI support.
1363 GDB's remote protocol has been extended to include support for hosted
1364 file I/O (where the remote target uses GDB's file system). See GDB's
1365 remote protocol documentation for details.
1367 * All targets using the new architecture framework.
1369 All of GDB's targets have been updated to use the new internal
1370 architecture framework. The way is now open for future GDB releases
1371 to include cross-architecture native debugging support (i386 on amd64,
1374 * GNU/Linux's Thread Local Storage (TLS)
1376 GDB now includes support for for the GNU/Linux implementation of
1377 per-thread variables.
1379 * GNU/Linux's Native POSIX Thread Library (NPTL)
1381 GDB's thread code has been updated to work with either the new
1382 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1384 * Separate debug info.
1386 GDB, in conjunction with BINUTILS, now supports a mechanism for
1387 automatically loading debug information from a separate file. Instead
1388 of shipping full debug and non-debug versions of system libraries,
1389 system integrators can now instead ship just the stripped libraries
1390 and optional debug files.
1392 * DWARF 2 Location Expressions
1394 DWARF 2 Location Expressions allow the compiler to more completely
1395 describe the location of variables (even in optimized code) to the
1398 GDB now includes preliminary support for location expressions (support
1399 for DW_OP_piece is still missing).
1403 A number of long standing bugs that caused GDB to die while starting a
1404 Java application have been fixed. GDB's Java support is now
1405 considered "useable".
1407 * GNU/Linux support for fork, vfork, and exec.
1409 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1410 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1413 * GDB supports logging output to a file
1415 There are two new commands, "set logging" and "show logging", which can be
1416 used to capture GDB's output to a file.
1418 * The meaning of "detach" has changed for gdbserver
1420 The "detach" command will now resume the application, as documented. To
1421 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1424 * d10v, m68hc11 `regs' command deprecated
1426 The `info registers' command has been updated so that it displays the
1427 registers using a format identical to the old `regs' command.
1431 A new command, "maint set profile on/off", has been added. This command can
1432 be used to enable or disable profiling while running GDB, to profile a
1433 session or a set of commands. In addition there is a new configure switch,
1434 "--enable-profiling", which will cause GDB to be compiled with profiling
1435 data, for more informative profiling results.
1437 * Default MI syntax changed to "mi2".
1439 The default MI (machine interface) syntax, enabled by the command line
1440 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1441 "mi1", can be enabled by specifying the option "-i=mi1".
1443 Support for the original "mi0" syntax (included in GDB 5.0) has been
1446 Fix for gdb/192: removed extraneous space when displaying frame level.
1447 Fix for gdb/672: update changelist is now output in mi list format.
1448 Fix for gdb/702: a -var-assign that updates the value now shows up
1449 in a subsequent -var-update.
1451 * New native configurations.
1453 FreeBSD/amd64 x86_64-*-freebsd*
1455 * Multi-arched targets.
1457 HP/PA HPUX11 hppa*-*-hpux*
1458 Renesas M32R/D w/simulator m32r-*-elf*
1460 * OBSOLETE configurations and files
1462 Configurations that have been declared obsolete in this release have
1463 been commented out. Unless there is activity to revive these
1464 configurations, the next release of GDB will have their sources
1465 permanently REMOVED.
1467 Z8000 simulator z8k-zilog-none or z8ksim
1468 Matsushita MN10200 w/simulator mn10200-*-*
1469 H8/500 simulator h8500-hitachi-hms or h8500hms
1470 HP/PA running BSD hppa*-*-bsd*
1471 HP/PA running OSF/1 hppa*-*-osf*
1472 HP/PA Pro target hppa*-*-pro*
1473 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1474 Sequent family i[3456]86-sequent-sysv4*
1475 i[3456]86-sequent-sysv*
1476 i[3456]86-sequent-bsd*
1477 Tsqware Sparclet sparclet-*-*
1478 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1480 * REMOVED configurations and files
1483 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1484 IBM AIX PS/2 i[3456]86-*-aix
1485 i386 running Mach 3.0 i[3456]86-*-mach3*
1486 i386 running Mach i[3456]86-*-mach*
1487 i386 running OSF/1 i[3456]86-*osf1mk*
1488 HP/Apollo 68k Family m68*-apollo*-sysv*,
1490 m68*-hp-bsd*, m68*-hp-hpux*
1491 Argonaut Risc Chip (ARC) arc-*-*
1492 Mitsubishi D30V d30v-*-*
1493 Fujitsu FR30 fr30-*-elf*
1494 OS/9000 i[34]86-*-os9k
1495 I960 with MON960 i960-*-coff
1497 * MIPS $fp behavior changed
1499 The convenience variable $fp, for the MIPS, now consistently returns
1500 the address of the current frame's base. Previously, depending on the
1501 context, $fp could refer to either $sp or the current frame's base
1502 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1503 The GNU Source-Level Debugger''.
1505 *** Changes in GDB 5.3:
1507 * GNU/Linux shared library multi-threaded performance improved.
1509 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1510 `/proc', in preference to `ptrace' for memory reads. This may result
1511 in an improvement in the start-up time of multi-threaded, shared
1512 library applications when run under GDB. One GDB user writes: ``loads
1513 shared libs like mad''.
1515 * ``gdbserver'' now supports multi-threaded applications on some targets
1517 Support for debugging multi-threaded applications which use
1518 the GNU/Linux LinuxThreads package has been added for
1519 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1520 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1522 * GDB now supports C/C++ preprocessor macros.
1524 GDB now expands preprocessor macro invocations in C/C++ expressions,
1525 and provides various commands for showing macro definitions and how
1528 The new command `macro expand EXPRESSION' expands any macro
1529 invocations in expression, and shows the result.
1531 The new command `show macro MACRO-NAME' shows the definition of the
1532 macro named MACRO-NAME, and where it was defined.
1534 Most compilers don't include information about macros in the debugging
1535 information by default. In GCC 3.1, for example, you need to compile
1536 your program with the options `-gdwarf-2 -g3'. If the macro
1537 information is present in the executable, GDB will read it.
1539 * Multi-arched targets.
1541 DEC Alpha (partial) alpha*-*-*
1542 DEC VAX (partial) vax-*-*
1544 National Semiconductor NS32000 (partial) ns32k-*-*
1545 Motorola 68000 (partial) m68k-*-*
1546 Motorola MCORE mcore-*-*
1550 Fujitsu FRV architecture added by Red Hat frv*-*-*
1553 * New native configurations
1555 Alpha NetBSD alpha*-*-netbsd*
1556 SH NetBSD sh*-*-netbsdelf*
1557 MIPS NetBSD mips*-*-netbsd*
1558 UltraSPARC NetBSD sparc64-*-netbsd*
1560 * OBSOLETE configurations and files
1562 Configurations that have been declared obsolete in this release have
1563 been commented out. Unless there is activity to revive these
1564 configurations, the next release of GDB will have their sources
1565 permanently REMOVED.
1567 Mitsubishi D30V d30v-*-*
1568 OS/9000 i[34]86-*-os9k
1569 IBM AIX PS/2 i[3456]86-*-aix
1570 Fujitsu FR30 fr30-*-elf*
1571 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1572 Argonaut Risc Chip (ARC) arc-*-*
1573 i386 running Mach 3.0 i[3456]86-*-mach3*
1574 i386 running Mach i[3456]86-*-mach*
1575 i386 running OSF/1 i[3456]86-*osf1mk*
1576 HP/Apollo 68k Family m68*-apollo*-sysv*,
1578 m68*-hp-bsd*, m68*-hp-hpux*
1579 I960 with MON960 i960-*-coff
1581 * OBSOLETE languages
1583 CHILL, a Pascal like language used by telecommunications companies.
1585 * REMOVED configurations and files
1587 AMD 29k family via UDI a29k-amd-udi, udi29k
1588 A29K VxWorks a29k-*-vxworks
1589 AMD 29000 embedded, using EBMON a29k-none-none
1590 AMD 29000 embedded with COFF a29k-none-coff
1591 AMD 29000 embedded with a.out a29k-none-aout
1593 testsuite/gdb.hp/gdb.threads-hp/ directory
1595 * New command "set max-user-call-depth <nnn>"
1597 This command allows the user to limit the call depth of user-defined
1598 commands. The default is 1024.
1600 * Changes in FreeBSD/i386 native debugging.
1602 Support for the "generate-core-file" has been added.
1604 * New commands "dump", "append", and "restore".
1606 These commands allow data to be copied from target memory
1607 to a bfd-format or binary file (dump and append), and back
1608 from a file into memory (restore).
1610 * Improved "next/step" support on multi-processor Alpha Tru64.
1612 The previous single-step mechanism could cause unpredictable problems,
1613 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1614 of a software single-step mechanism prevents this.
1616 *** Changes in GDB 5.2.1:
1624 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1625 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1626 Fix, by Joel Brobecker imported from mainline.
1628 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1629 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1630 Fix, by Fred Fish, imported from mainline.
1632 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1633 Surprisingly enough, it works now.
1634 By Michal Ludvig, imported from mainline.
1636 i386 hardware watchpoint support:
1637 avoid misses on second run for some targets.
1638 By Pierre Muller, imported from mainline.
1640 *** Changes in GDB 5.2:
1642 * New command "set trust-readonly-sections on[off]".
1644 This command is a hint that tells gdb that read-only sections
1645 really are read-only (ie. that their contents will not change).
1646 In this mode, gdb will go to the object file rather than the
1647 target to read memory from read-only sections (such as ".text").
1648 This can be a significant performance improvement on some
1649 (notably embedded) targets.
1651 * New command "generate-core-file" (or "gcore").
1653 This new gdb command allows the user to drop a core file of the child
1654 process state at any time. So far it's been implemented only for
1655 GNU/Linux and Solaris, but should be relatively easily ported to other
1656 hosts. Argument is core file name (defaults to core.<pid>).
1658 * New command line option
1660 GDB now accepts --pid or -p followed by a process id.
1662 * Change in command line behavior -- corefiles vs. process ids.
1664 There is a subtle behavior in the way in which GDB handles
1665 command line arguments. The first non-flag argument is always
1666 a program to debug, but the second non-flag argument may either
1667 be a corefile or a process id. Previously, GDB would attempt to
1668 open the second argument as a corefile, and if that failed, would
1669 issue a superfluous error message and then attempt to attach it as
1670 a process. Now, if the second argument begins with a non-digit,
1671 it will be treated as a corefile. If it begins with a digit,
1672 GDB will attempt to attach it as a process, and if no such process
1673 is found, will then attempt to open it as a corefile.
1675 * Changes in ARM configurations.
1677 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1678 configuration is fully multi-arch.
1680 * New native configurations
1682 ARM NetBSD arm*-*-netbsd*
1683 x86 OpenBSD i[3456]86-*-openbsd*
1684 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1685 Sparc64 running FreeBSD sparc64-*-freebsd*
1689 Sanyo XStormy16 xstormy16-elf
1691 * OBSOLETE configurations and files
1693 Configurations that have been declared obsolete in this release have
1694 been commented out. Unless there is activity to revive these
1695 configurations, the next release of GDB will have their sources
1696 permanently REMOVED.
1698 AMD 29k family via UDI a29k-amd-udi, udi29k
1699 A29K VxWorks a29k-*-vxworks
1700 AMD 29000 embedded, using EBMON a29k-none-none
1701 AMD 29000 embedded with COFF a29k-none-coff
1702 AMD 29000 embedded with a.out a29k-none-aout
1704 testsuite/gdb.hp/gdb.threads-hp/ directory
1706 * REMOVED configurations and files
1708 TI TMS320C80 tic80-*-*
1710 PowerPC Solaris powerpcle-*-solaris*
1711 PowerPC Windows NT powerpcle-*-cygwin32
1712 PowerPC Netware powerpc-*-netware*
1713 Harris/CXUX m88k m88*-harris-cxux*
1714 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1715 ns32k-utek-sysv* ns32k-utek-*
1716 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1717 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1718 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1719 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1720 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1722 * Changes to command line processing
1724 The new `--args' feature can be used to specify command-line arguments
1725 for the inferior from gdb's command line.
1727 * Changes to key bindings
1729 There is a new `operate-and-get-next' function bound to `C-o'.
1731 *** Changes in GDB 5.1.1
1733 Fix compile problem on DJGPP.
1735 Fix a problem with floating-point registers on the i386 being
1738 Fix to stop GDB crashing on .debug_str debug info.
1740 Numerous documentation fixes.
1742 Numerous testsuite fixes.
1744 *** Changes in GDB 5.1:
1746 * New native configurations
1748 Alpha FreeBSD alpha*-*-freebsd*
1749 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1750 MIPS GNU/Linux mips*-*-linux*
1751 MIPS SGI Irix 6.x mips*-sgi-irix6*
1752 ia64 AIX ia64-*-aix*
1753 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1757 Motorola 68HC11 and 68HC12 m68hc11-elf
1759 UltraSparc running GNU/Linux sparc64-*-linux*
1761 * OBSOLETE configurations and files
1763 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1764 Harris/CXUX m88k m88*-harris-cxux*
1765 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1766 ns32k-utek-sysv* ns32k-utek-*
1767 TI TMS320C80 tic80-*-*
1769 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1770 PowerPC Solaris powerpcle-*-solaris*
1771 PowerPC Windows NT powerpcle-*-cygwin32
1772 PowerPC Netware powerpc-*-netware*
1773 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1774 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1775 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1776 Apple Macintosh (MPW) host N/A
1778 stuff.c (Program to stuff files into a specially prepared space in kdb)
1779 kdb-start.c (Main loop for the standalone kernel debugger)
1781 Configurations that have been declared obsolete in this release have
1782 been commented out. Unless there is activity to revive these
1783 configurations, the next release of GDB will have their sources
1784 permanently REMOVED.
1786 * REMOVED configurations and files
1788 Altos 3068 m68*-altos-*
1789 Convex c1-*-*, c2-*-*
1791 ARM RISCix arm-*-* (as host)
1795 * GDB has been converted to ISO C.
1797 GDB's source code has been converted to ISO C. In particular, the
1798 sources are fully protoized, and rely on standard headers being
1803 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1805 * The MI enabled by default.
1807 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1808 revised and enabled by default. Packages which use GDB as a debugging
1809 engine behind a UI or another front end are encouraged to switch to
1810 using the GDB/MI interface, instead of the old annotations interface
1811 which is now deprecated.
1813 * Support for debugging Pascal programs.
1815 GDB now includes support for debugging Pascal programs. The following
1816 main features are supported:
1818 - Pascal-specific data types such as sets;
1820 - automatic recognition of Pascal sources based on file-name
1823 - Pascal-style display of data types, variables, and functions;
1825 - a Pascal expression parser.
1827 However, some important features are not yet supported.
1829 - Pascal string operations are not supported at all;
1831 - there are some problems with boolean types;
1833 - Pascal type hexadecimal constants are not supported
1834 because they conflict with the internal variables format;
1836 - support for Pascal objects and classes is not full yet;
1838 - unlike Pascal, GDB is case-sensitive for symbol names.
1840 * Changes in completion.
1842 Commands such as `shell', `run' and `set args', which pass arguments
1843 to inferior programs, now complete on file names, similar to what
1844 users expect at the shell prompt.
1846 Commands which accept locations, such as `disassemble', `print',
1847 `breakpoint', `until', etc. now complete on filenames as well as
1848 program symbols. Thus, if you type "break foob TAB", and the source
1849 files linked into the programs include `foobar.c', that file name will
1850 be one of the candidates for completion. However, file names are not
1851 considered for completion after you typed a colon that delimits a file
1852 name from a name of a function in that file, as in "break foo.c:bar".
1854 `set demangle-style' completes on available demangling styles.
1856 * New platform-independent commands:
1858 It is now possible to define a post-hook for a command as well as a
1859 hook that runs before the command. For more details, see the
1860 documentation of `hookpost' in the GDB manual.
1862 * Changes in GNU/Linux native debugging.
1864 Support for debugging multi-threaded programs has been completely
1865 revised for all platforms except m68k and sparc. You can now debug as
1866 many threads as your system allows you to have.
1868 Attach/detach is supported for multi-threaded programs.
1870 Support for SSE registers was added for x86. This doesn't work for
1871 multi-threaded programs though.
1873 * Changes in MIPS configurations.
1875 Multi-arch support is enabled for all MIPS configurations.
1877 GDB can now be built as native debugger on SGI Irix 6.x systems for
1878 debugging n32 executables. (Debugging 64-bit executables is not yet
1881 * Unified support for hardware watchpoints in all x86 configurations.
1883 Most (if not all) native x86 configurations support hardware-assisted
1884 breakpoints and watchpoints in a unified manner. This support
1885 implements debug register sharing between watchpoints, which allows to
1886 put a virtually infinite number of watchpoints on the same address,
1887 and also supports watching regions up to 16 bytes with several debug
1890 The new maintenance command `maintenance show-debug-regs' toggles
1891 debugging print-outs in functions that insert, remove, and test
1892 watchpoints and hardware breakpoints.
1894 * Changes in the DJGPP native configuration.
1896 New command ``info dos sysinfo'' displays assorted information about
1897 the CPU, OS, memory, and DPMI server.
1899 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1900 display information about segment descriptors stored in GDT, LDT, and
1903 New commands ``info dos pde'' and ``info dos pte'' display entries
1904 from Page Directory and Page Tables (for now works with CWSDPMI only).
1905 New command ``info dos address-pte'' displays the Page Table entry for
1906 a given linear address.
1908 GDB can now pass command lines longer than 126 characters to the
1909 program being debugged (requires an update to the libdbg.a library
1910 which is part of the DJGPP development kit).
1912 DWARF2 debug info is now supported.
1914 It is now possible to `step' and `next' through calls to `longjmp'.
1916 * Changes in documentation.
1918 All GDB documentation was converted to GFDL, the GNU Free
1919 Documentation License.
1921 Tracepoints-related commands are now fully documented in the GDB
1924 TUI, the Text-mode User Interface, is now documented in the manual.
1926 Tracepoints-related commands are now fully documented in the GDB
1929 The "GDB Internals" manual now has an index. It also includes
1930 documentation of `ui_out' functions, GDB coding standards, x86
1931 hardware watchpoints, and memory region attributes.
1933 * GDB's version number moved to ``version.in''
1935 The Makefile variable VERSION has been replaced by the file
1936 ``version.in''. People creating GDB distributions should update the
1937 contents of this file.
1941 GUD support is now a standard part of the EMACS distribution.
1943 *** Changes in GDB 5.0:
1945 * Improved support for debugging FP programs on x86 targets
1947 Unified and much-improved support for debugging floating-point
1948 programs on all x86 targets. In particular, ``info float'' now
1949 displays the FP registers in the same format on all x86 targets, with
1950 greater level of detail.
1952 * Improvements and bugfixes in hardware-assisted watchpoints
1954 It is now possible to watch array elements, struct members, and
1955 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1956 on x86 targets no longer erroneously trigger when the address is
1959 * Improvements in the native DJGPP version of GDB
1961 The distribution now includes all the scripts and auxiliary files
1962 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1963 machines ``out of the box''.
1965 The DJGPP version can now debug programs that use signals. It is
1966 possible to catch signals that happened in the debuggee, deliver
1967 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1968 would kill the program being debugged.) Programs that hook hardware
1969 interrupts (keyboard, timer, etc.) can also be debugged.
1971 It is now possible to debug DJGPP programs that redirect their
1972 standard handles or switch them to raw (as opposed to cooked) mode, or
1973 even close them. The command ``run < foo > bar'' works as expected,
1974 and ``info terminal'' reports useful information about the debuggee's
1975 terminal, including raw/cooked mode, redirection, etc.
1977 The DJGPP version now uses termios functions for console I/O, which
1978 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1981 DOS-style file names with drive letters are now fully supported by
1984 It is now possible to debug DJGPP programs that switch their working
1985 directory. It is also possible to rerun the debuggee any number of
1986 times without restarting GDB; thus, you can use the same setup,
1987 breakpoints, etc. for many debugging sessions.
1989 * New native configurations
1991 ARM GNU/Linux arm*-*-linux*
1992 PowerPC GNU/Linux powerpc-*-linux*
1996 Motorola MCore mcore-*-*
1997 x86 VxWorks i[3456]86-*-vxworks*
1998 PowerPC VxWorks powerpc-*-vxworks*
1999 TI TMS320C80 tic80-*-*
2001 * OBSOLETE configurations
2003 Altos 3068 m68*-altos-*
2004 Convex c1-*-*, c2-*-*
2006 ARM RISCix arm-*-* (as host)
2009 Configurations that have been declared obsolete will be commented out,
2010 but the code will be left in place. If there is no activity to revive
2011 these configurations before the next release of GDB, the sources will
2012 be permanently REMOVED.
2014 * Gould support removed
2016 Support for the Gould PowerNode and NP1 has been removed.
2018 * New features for SVR4
2020 On SVR4 native platforms (such as Solaris), if you attach to a process
2021 without first loading a symbol file, GDB will now attempt to locate and
2022 load symbols from the running process's executable file.
2024 * Many C++ enhancements
2026 C++ support has been greatly improved. Overload resolution now works properly
2027 in almost all cases. RTTI support is on the way.
2029 * Remote targets can connect to a sub-program
2031 A popen(3) style serial-device has been added. This device starts a
2032 sub-process (such as a stand-alone simulator) and then communicates
2033 with that. The sub-program to run is specified using the syntax
2034 ``|<program> <args>'' vis:
2036 (gdb) set remotedebug 1
2037 (gdb) target extended-remote |mn10300-elf-sim program-args
2039 * MIPS 64 remote protocol
2041 A long standing bug in the mips64 remote protocol where by GDB
2042 expected certain 32 bit registers (ex SR) to be transfered as 32
2043 instead of 64 bits has been fixed.
2045 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2046 added to provide backward compatibility with older versions of GDB.
2048 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2050 The command ``set remotebinarydownload'' command has been replaced by
2051 ``set remote X-packet''. Other commands in ``set remote'' family
2052 include ``set remote P-packet''.
2054 * Breakpoint commands accept ranges.
2056 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2057 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2058 ``tracepoint passcount'' also accepts a range of tracepoints.
2060 * ``apropos'' command added.
2062 The ``apropos'' command searches through command names and
2063 documentation strings, printing out matches, making it much easier to
2064 try to find a command that does what you are looking for.
2068 A new machine oriented interface (MI) has been added to GDB. This
2069 interface is designed for debug environments running GDB as a separate
2070 process. This is part of the long term libGDB project. See the
2071 "GDB/MI" chapter of the GDB manual for further information. It can be
2072 enabled by configuring with:
2074 .../configure --enable-gdbmi
2076 *** Changes in GDB-4.18:
2078 * New native configurations
2080 HP-UX 10.20 hppa*-*-hpux10.20
2081 HP-UX 11.x hppa*-*-hpux11.0*
2082 M68K GNU/Linux m68*-*-linux*
2086 Fujitsu FR30 fr30-*-elf*
2087 Intel StrongARM strongarm-*-*
2088 Mitsubishi D30V d30v-*-*
2090 * OBSOLETE configurations
2092 Gould PowerNode, NP1 np1-*-*, pn-*-*
2094 Configurations that have been declared obsolete will be commented out,
2095 but the code will be left in place. If there is no activity to revive
2096 these configurations before the next release of GDB, the sources will
2097 be permanently REMOVED.
2101 As a compatibility experiment, GDB's source files buildsym.h and
2102 buildsym.c have been converted to pure standard C, no longer
2103 containing any K&R compatibility code. We believe that all systems in
2104 use today either come with a standard C compiler, or have a GCC port
2105 available. If this is not true, please report the affected
2106 configuration to bug-gdb@gnu.org immediately. See the README file for
2107 information about getting a standard C compiler if you don't have one
2112 GDB now uses readline 2.2.
2114 * set extension-language
2116 You can now control the mapping between filename extensions and source
2117 languages by using the `set extension-language' command. For instance,
2118 you can ask GDB to treat .c files as C++ by saying
2119 set extension-language .c c++
2120 The command `info extensions' lists all of the recognized extensions
2121 and their associated languages.
2123 * Setting processor type for PowerPC and RS/6000
2125 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2126 you can use the `set processor' command to specify what variant of the
2127 PowerPC family you are debugging. The command
2131 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2132 following PowerPC and RS6000 variants:
2134 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2135 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2137 403GC IBM PowerPC 403GC
2138 505 Motorola PowerPC 505
2139 860 Motorola PowerPC 860 or 850
2140 601 Motorola PowerPC 601
2141 602 Motorola PowerPC 602
2142 603 Motorola/IBM PowerPC 603 or 603e
2143 604 Motorola PowerPC 604 or 604e
2144 750 Motorola/IBM PowerPC 750 or 750
2146 At the moment, this command just tells GDB what to name the
2147 special-purpose processor registers. Since almost all the affected
2148 registers are inaccessible to user-level programs, this command is
2149 only useful for remote debugging in its present form.
2153 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2154 more extensive support for HP-UX. Added features include shared
2155 library support, kernel threads and hardware watchpoints for 11.00,
2156 support for HP's ANSI C and C++ compilers, and a compatibility mode
2157 for xdb and dbx commands.
2161 HP's donation includes the new concept of catchpoints, which is a
2162 generalization of the old catch command. On HP-UX, it is now possible
2163 to catch exec, fork, and vfork, as well as library loading.
2165 This means that the existing catch command has changed; its first
2166 argument now specifies the type of catch to be set up. See the
2167 output of "help catch" for a list of catchpoint types.
2169 * Debugging across forks
2171 On HP-UX, you can choose which process to debug when a fork() happens
2176 HP has donated a curses-based terminal user interface (TUI). To get
2177 it, build with --enable-tui. Although this can be enabled for any
2178 configuration, at present it only works for native HP debugging.
2180 * GDB remote protocol additions
2182 A new protocol packet 'X' that writes binary data is now available.
2183 Default behavior is to try 'X', then drop back to 'M' if the stub
2184 fails to respond. The settable variable `remotebinarydownload'
2185 allows explicit control over the use of 'X'.
2187 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2188 full 64-bit address. The command
2190 set remoteaddresssize 32
2192 can be used to revert to the old behaviour. For existing remote stubs
2193 the change should not be noticed, as the additional address information
2196 In order to assist in debugging stubs, you may use the maintenance
2197 command `packet' to send any text string to the stub. For instance,
2199 maint packet heythere
2201 sends the packet "$heythere#<checksum>". Note that it is very easy to
2202 disrupt a debugging session by sending the wrong packet at the wrong
2205 The compare-sections command allows you to compare section data on the
2206 target to what is in the executable file without uploading or
2207 downloading, by comparing CRC checksums.
2209 * Tracing can collect general expressions
2211 You may now collect general expressions at tracepoints. This requires
2212 further additions to the target-side stub; see tracepoint.c and
2213 doc/agentexpr.texi for further details.
2215 * mask-address variable for Mips
2217 For Mips targets, you may control the zeroing of the upper 32 bits of
2218 a 64-bit address by entering `set mask-address on'. This is mainly
2219 of interest to users of embedded R4xxx and R5xxx processors.
2221 * Higher serial baud rates
2223 GDB's serial code now allows you to specify baud rates 57600, 115200,
2224 230400, and 460800 baud. (Note that your host system may not be able
2225 to achieve all of these rates.)
2229 The i960 configuration now includes an initial implementation of a
2230 builtin simulator, contributed by Jim Wilson.
2233 *** Changes in GDB-4.17:
2235 * New native configurations
2237 Alpha GNU/Linux alpha*-*-linux*
2238 Unixware 2.x i[3456]86-unixware2*
2239 Irix 6.x mips*-sgi-irix6*
2240 PowerPC GNU/Linux powerpc-*-linux*
2241 PowerPC Solaris powerpcle-*-solaris*
2242 Sparc GNU/Linux sparc-*-linux*
2243 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2247 Argonaut Risc Chip (ARC) arc-*-*
2248 Hitachi H8/300S h8300*-*-*
2249 Matsushita MN10200 w/simulator mn10200-*-*
2250 Matsushita MN10300 w/simulator mn10300-*-*
2251 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2252 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2253 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2254 Mitsubishi D10V w/simulator d10v-*-*
2255 Mitsubishi M32R/D w/simulator m32r-*-elf*
2256 Tsqware Sparclet sparclet-*-*
2257 NEC V850 w/simulator v850-*-*
2259 * New debugging protocols
2261 ARM with RDI protocol arm*-*-*
2262 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2263 DDB and LSI variants of PMON protocol mips*-*-*
2264 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2265 PowerPC with SDS protocol powerpc{,le}-*-eabi
2266 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2270 All configurations can now understand and use the DWARF 2 debugging
2271 format. The choice is automatic, if the symbol file contains DWARF 2
2276 GDB now includes basic Java language support. This support is
2277 only useful with Java compilers that produce native machine code.
2279 * solib-absolute-prefix and solib-search-path
2281 For SunOS and SVR4 shared libraries, you may now set the prefix for
2282 loading absolute shared library symbol files, and the search path for
2283 locating non-absolute shared library symbol files.
2285 * Live range splitting
2287 GDB can now effectively debug code for which GCC has performed live
2288 range splitting as part of its optimization. See gdb/doc/LRS for
2289 more details on the expected format of the stabs information.
2293 GDB's support for the GNU Hurd, including thread debugging, has been
2294 updated to work with current versions of the Hurd.
2298 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2299 instruction set. ARM GDB automatically detects when Thumb
2300 instructions are in use, and adjusts disassembly and backtracing
2305 GDB's MIPS target configurations now handle the MIP16 16-bit
2310 GDB now includes support for overlays; if an executable has been
2311 linked such that multiple sections are based at the same address, GDB
2312 will decide which section to use for symbolic info. You can choose to
2313 control the decision manually, using overlay commands, or implement
2314 additional target-side support and use "overlay load-target" to bring
2315 in the overlay mapping. Do "help overlay" for more detail.
2319 The command "info symbol <address>" displays information about
2320 the symbol at the specified address.
2324 The standard remote protocol now includes an extension that allows
2325 asynchronous collection and display of trace data. This requires
2326 extensive support in the target-side debugging stub. Tracing mode
2327 includes a new interaction mode in GDB and new commands: see the
2328 file tracepoint.c for more details.
2332 Configurations for embedded MIPS now include a simulator contributed
2333 by Cygnus Solutions. The simulator supports the instruction sets
2334 of most MIPS variants.
2338 Sparc configurations may now include the ERC32 simulator contributed
2339 by the European Space Agency. The simulator is not built into
2340 Sparc targets by default; configure with --enable-sim to include it.
2344 For target configurations that may include multiple variants of a
2345 basic architecture (such as MIPS and SH), you may now set the
2346 architecture explicitly. "set arch" sets, "info arch" lists
2347 the possible architectures.
2349 *** Changes in GDB-4.16:
2351 * New native configurations
2353 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2354 M68K NetBSD m68k-*-netbsd*
2355 PowerPC AIX 4.x powerpc-*-aix*
2356 PowerPC MacOS powerpc-*-macos*
2357 PowerPC Windows NT powerpcle-*-cygwin32
2358 RS/6000 AIX 4.x rs6000-*-aix4*
2362 ARM with RDP protocol arm-*-*
2363 I960 with MON960 i960-*-coff
2364 MIPS VxWorks mips*-*-vxworks*
2365 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2366 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2368 Matra Sparclet sparclet-*-*
2372 The powerpc-eabi configuration now includes the PSIM simulator,
2373 contributed by Andrew Cagney, with assistance from Mike Meissner.
2374 PSIM is a very elaborate model of the PowerPC, including not only
2375 basic instruction set execution, but also details of execution unit
2376 performance and I/O hardware. See sim/ppc/README for more details.
2380 GDB now works with Solaris 2.5.
2382 * Windows 95/NT native
2384 GDB will now work as a native debugger on Windows 95 and Windows NT.
2385 To build it from source, you must use the "gnu-win32" environment,
2386 which uses a DLL to emulate enough of Unix to run the GNU tools.
2387 Further information, binaries, and sources are available at
2388 ftp.cygnus.com, under pub/gnu-win32.
2390 * dont-repeat command
2392 If a user-defined command includes the command `dont-repeat', then the
2393 command will not be repeated if the user just types return. This is
2394 useful if the command is time-consuming to run, so that accidental
2395 extra keystrokes don't run the same command many times.
2397 * Send break instead of ^C
2399 The standard remote protocol now includes an option to send a break
2400 rather than a ^C to the target in order to interrupt it. By default,
2401 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2403 * Remote protocol timeout
2405 The standard remote protocol includes a new variable `remotetimeout'
2406 that allows you to set the number of seconds before GDB gives up trying
2407 to read from the target. The default value is 2.
2409 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2411 By default GDB will automatically keep track of objects as they are
2412 loaded and unloaded by the dynamic linker. By using the command `set
2413 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2414 when shared library events occur, thus allowing you to set breakpoints
2415 in shared libraries which are explicitly loaded by the inferior.
2417 Note this feature does not work on hpux8. On hpux9 you must link
2418 /usr/lib/end.o into your program. This feature should work
2419 automatically on hpux10.
2421 * Irix 5.x hardware watchpoint support
2423 Irix 5 configurations now support the use of hardware watchpoints.
2425 * Mips protocol "SYN garbage limit"
2427 When debugging a Mips target using the `target mips' protocol, you
2428 may set the number of characters that GDB will ignore by setting
2429 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2430 every character. The default value is 1050.
2432 * Recording and replaying remote debug sessions
2434 If you set `remotelogfile' to the name of a file, gdb will write to it
2435 a recording of a remote debug session. This recording may then be
2436 replayed back to gdb using "gdbreplay". See gdbserver/README for
2437 details. This is useful when you have a problem with GDB while doing
2438 remote debugging; you can make a recording of the session and send it
2439 to someone else, who can then recreate the problem.
2441 * Speedups for remote debugging
2443 GDB includes speedups for downloading and stepping MIPS systems using
2444 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2445 and more efficient S-record downloading.
2447 * Memory use reductions and statistics collection
2449 GDB now uses less memory and reports statistics about memory usage.
2450 Try the `maint print statistics' command, for example.
2452 *** Changes in GDB-4.15:
2454 * Psymtabs for XCOFF
2456 The symbol reader for AIX GDB now uses partial symbol tables. This
2457 can greatly improve startup time, especially for large executables.
2459 * Remote targets use caching
2461 Remote targets now use a data cache to speed up communication with the
2462 remote side. The data cache could lead to incorrect results because
2463 it doesn't know about volatile variables, thus making it impossible to
2464 debug targets which use memory mapped I/O devices. `set remotecache
2465 off' turns the the data cache off.
2467 * Remote targets may have threads
2469 The standard remote protocol now includes support for multiple threads
2470 in the target system, using new protocol commands 'H' and 'T'. See
2471 gdb/remote.c for details.
2475 If GDB is configured with `--enable-netrom', then it will include
2476 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2477 acts as though it is a bank of ROM on the target board, but you can
2478 write into it over the network. GDB's support consists only of
2479 support for fast loading into the emulated ROM; to debug, you must use
2480 another protocol, such as standard remote protocol. The usual
2481 sequence is something like
2483 target nrom <netrom-hostname>
2485 target remote <netrom-hostname>:1235
2489 GDB now includes support for the Apple Macintosh, as a host only. It
2490 may be run as either an MPW tool or as a standalone application, and
2491 it can debug through the serial port. All the usual GDB commands are
2492 available, but to the target command, you must supply "serial" as the
2493 device type instead of "/dev/ttyXX". See mpw-README in the main
2494 directory for more information on how to build. The MPW configuration
2495 scripts */mpw-config.in support only a few targets, and only the
2496 mips-idt-ecoff target has been tested.
2500 GDB configuration now uses autoconf. This is not user-visible,
2501 but does simplify configuration and building.
2505 GDB now supports hpux10.
2507 *** Changes in GDB-4.14:
2509 * New native configurations
2511 x86 FreeBSD i[345]86-*-freebsd
2512 x86 NetBSD i[345]86-*-netbsd
2513 NS32k NetBSD ns32k-*-netbsd
2514 Sparc NetBSD sparc-*-netbsd
2518 A29K VxWorks a29k-*-vxworks
2519 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2520 CPU32 EST-300 emulator m68*-*-est*
2521 PowerPC ELF powerpc-*-elf
2524 * Alpha OSF/1 support for procfs
2526 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2527 possible to attach to running processes. As the mounting of the /proc
2528 filesystem is optional on the Alpha, GDB automatically determines
2529 the availability of /proc during startup. This can lead to problems
2530 if /proc is unmounted after GDB has been started.
2532 * Arguments to user-defined commands
2534 User commands may accept up to 10 arguments separated by whitespace.
2535 Arguments are accessed within the user command via $arg0..$arg9. A
2538 print $arg0 + $arg1 + $arg2
2540 To execute the command use:
2543 Defines the command "adder" which prints the sum of its three arguments.
2544 Note the arguments are text substitutions, so they may reference variables,
2545 use complex expressions, or even perform inferior function calls.
2547 * New `if' and `while' commands
2549 This makes it possible to write more sophisticated user-defined
2550 commands. Both commands take a single argument, which is the
2551 expression to evaluate, and must be followed by the commands to
2552 execute, one per line, if the expression is nonzero, the list being
2553 terminated by the word `end'. The `if' command list may include an
2554 `else' word, which causes the following commands to be executed only
2555 if the expression is zero.
2557 * Fortran source language mode
2559 GDB now includes partial support for Fortran 77. It will recognize
2560 Fortran programs and can evaluate a subset of Fortran expressions, but
2561 variables and functions may not be handled correctly. GDB will work
2562 with G77, but does not yet know much about symbols emitted by other
2565 * Better HPUX support
2567 Most debugging facilities now work on dynamic executables for HPPAs
2568 running hpux9 or later. You can attach to running dynamically linked
2569 processes, but by default the dynamic libraries will be read-only, so
2570 for instance you won't be able to put breakpoints in them. To change
2571 that behavior do the following before running the program:
2577 This will cause the libraries to be mapped private and read-write.
2578 To revert to the normal behavior, do this:
2584 You cannot set breakpoints or examine data in the library until after
2585 the library is loaded if the function/data symbols do not have
2588 GDB can now also read debug symbols produced by the HP C compiler on
2589 HPPAs (sorry, no C++, Fortran or 68k support).
2591 * Target byte order now dynamically selectable
2593 You can choose which byte order to use with a target system, via the
2594 commands "set endian big" and "set endian little", and you can see the
2595 current setting by using "show endian". You can also give the command
2596 "set endian auto", in which case GDB will use the byte order
2597 associated with the executable. Currently, only embedded MIPS
2598 configurations support dynamic selection of target byte order.
2600 * New DOS host serial code
2602 This version uses DPMI interrupts to handle buffered I/O, so you
2603 no longer need to run asynctsr when debugging boards connected to
2606 *** Changes in GDB-4.13:
2608 * New "complete" command
2610 This lists all the possible completions for the rest of the line, if it
2611 were to be given as a command itself. This is intended for use by emacs.
2613 * Trailing space optional in prompt
2615 "set prompt" no longer adds a space for you after the prompt you set. This
2616 allows you to set a prompt which ends in a space or one that does not.
2618 * Breakpoint hit counts
2620 "info break" now displays a count of the number of times the breakpoint
2621 has been hit. This is especially useful in conjunction with "ignore"; you
2622 can ignore a large number of breakpoint hits, look at the breakpoint info
2623 to see how many times the breakpoint was hit, then run again, ignoring one
2624 less than that number, and this will get you quickly to the last hit of
2627 * Ability to stop printing at NULL character
2629 "set print null-stop" will cause GDB to stop printing the characters of
2630 an array when the first NULL is encountered. This is useful when large
2631 arrays actually contain only short strings.
2633 * Shared library breakpoints
2635 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2636 breakpoints in shared libraries before the executable is run.
2638 * Hardware watchpoints
2640 There is a new hardware breakpoint for the watch command for sparclite
2641 targets. See gdb/sparclite/hw_breakpoint.note.
2643 Hardware watchpoints are also now supported under GNU/Linux.
2647 Annotations have been added. These are for use with graphical interfaces,
2648 and are still experimental. Currently only gdba.el uses these.
2650 * Improved Irix 5 support
2652 GDB now works properly with Irix 5.2.
2654 * Improved HPPA support
2656 GDB now works properly with the latest GCC and GAS.
2658 * New native configurations
2660 Sequent PTX4 i[34]86-sequent-ptx4
2661 HPPA running OSF/1 hppa*-*-osf*
2662 Atari TT running SVR4 m68*-*-sysv4*
2663 RS/6000 LynxOS rs6000-*-lynxos*
2667 OS/9000 i[34]86-*-os9k
2668 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2671 * Hitachi SH7000 and E7000-PC ICE support
2673 There is now support for communicating with the Hitachi E7000-PC ICE.
2674 This is available automatically when GDB is configured for the SH.
2678 As usual, a variety of small fixes and improvements, both generic
2679 and configuration-specific. See the ChangeLog for more detail.
2681 *** Changes in GDB-4.12:
2683 * Irix 5 is now supported
2687 GDB-4.12 on the HPPA has a number of changes which make it unable
2688 to debug the output from the currently released versions of GCC and
2689 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2690 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2691 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2694 *** Changes in GDB-4.11:
2696 * User visible changes:
2700 The "set remotedebug" option is now consistent between the mips remote
2701 target, remote targets using the gdb-specific protocol, UDI (AMD's
2702 debug protocol for the 29k) and the 88k bug monitor. It is now an
2703 integer specifying a debug level (normally 0 or 1, but 2 means more
2704 debugging info for the mips target).
2706 * DEC Alpha native support
2708 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2709 debug info, but GDB works fairly well with the DEC compiler and should
2710 work with a future GCC release. See the README file for a few
2711 Alpha-specific notes.
2713 * Preliminary thread implementation
2715 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2717 * LynxOS native and target support for 386
2719 This release has been hosted on LynxOS 2.2, and also can be configured
2720 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2723 * Improvements in C++ mangling/demangling.
2725 This release has much better g++ debugging, specifically in name
2726 mangling/demangling, virtual function calls, print virtual table,
2727 call methods, ...etc.
2729 *** Changes in GDB-4.10:
2731 * User visible changes:
2733 Remote debugging using the GDB-specific (`target remote') protocol now
2734 supports the `load' command. This is only useful if you have some
2735 other way of getting the stub to the target system, and you can put it
2736 somewhere in memory where it won't get clobbered by the download.
2738 Filename completion now works.
2740 When run under emacs mode, the "info line" command now causes the
2741 arrow to point to the line specified. Also, "info line" prints
2742 addresses in symbolic form (as well as hex).
2744 All vxworks based targets now support a user settable option, called
2745 vxworks-timeout. This option represents the number of seconds gdb
2746 should wait for responses to rpc's. You might want to use this if
2747 your vxworks target is, perhaps, a slow software simulator or happens
2748 to be on the far side of a thin network line.
2752 This release contains support for using a DEC alpha as a GDB host for
2753 cross debugging. Native alpha debugging is not supported yet.
2756 *** Changes in GDB-4.9:
2760 This is the first GDB release which is accompanied by a matching testsuite.
2761 The testsuite requires installation of dejagnu, which should be available
2762 via ftp from most sites that carry GNU software.
2766 'Cfront' style demangling has had its name changed to 'ARM' style, to
2767 emphasize that it was written from the specifications in the C++ Annotated
2768 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2769 disclaimers, it still generated too much confusion with users attempting to
2770 use gdb with AT&T cfront.
2774 GDB now uses a standard remote interface to a simulator library.
2775 So far, the library contains simulators for the Zilog Z8001/2, the
2776 Hitachi H8/300, H8/500 and Super-H.
2778 * New targets supported
2780 H8/300 simulator h8300-hitachi-hms or h8300hms
2781 H8/500 simulator h8500-hitachi-hms or h8500hms
2782 SH simulator sh-hitachi-hms or sh
2783 Z8000 simulator z8k-zilog-none or z8ksim
2784 IDT MIPS board over serial line mips-idt-ecoff
2786 Cross-debugging to GO32 targets is supported. It requires a custom
2787 version of the i386-stub.c module which is integrated with the
2788 GO32 memory extender.
2790 * New remote protocols
2792 MIPS remote debugging protocol.
2794 * New source languages supported
2796 This version includes preliminary support for Chill, a Pascal like language
2797 used by telecommunications companies. Chill support is also being integrated
2798 into the GNU compiler, but we don't know when it will be publically available.
2801 *** Changes in GDB-4.8:
2803 * HP Precision Architecture supported
2805 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2806 version of this support was available as a set of patches from the
2807 University of Utah. GDB does not support debugging of programs
2808 compiled with the HP compiler, because HP will not document their file
2809 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2810 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2812 Many problems in the preliminary version have been fixed.
2814 * Faster and better demangling
2816 We have improved template demangling and fixed numerous bugs in the GNU style
2817 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2818 character types (wchar_t) are now supported. Demangling of each symbol is now
2819 only done once, and is cached when the symbol table for a file is read in.
2820 This results in a small increase in memory usage for C programs, a moderate
2821 increase in memory usage for C++ programs, and a fantastic speedup in
2824 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2825 from the specifications in the Annotated Reference Manual, which AT&T's
2826 compiler does not actually implement.
2828 * G++ multiple inheritance compiler problem
2830 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2831 inheritance lattices was reworked to properly discover ambiguities. We
2832 recently found an example which causes this new algorithm to fail in a
2833 very subtle way, producing bad debug information for those classes.
2834 The file 'gcc.patch' (in this directory) can be applied to gcc to
2835 circumvent the problem. A future GCC release will contain a complete
2838 The previous G++ debug info problem (mentioned below for the gdb-4.7
2839 release) is fixed in gcc version 2.3.2.
2841 * Improved configure script
2843 The `configure' script will now attempt to guess your system type if
2844 you don't supply a host system type. The old scheme of supplying a
2845 host system triplet is preferable over using this. All the magic is
2846 done in the new `config.guess' script. Examine it for details.
2848 We have also brought our configure script much more in line with the FSF's
2849 version. It now supports the --with-xxx options. In particular,
2850 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2851 The resulting GDB will not be able to read arbitrary object file formats --
2852 only the format ``expected'' to be used on the configured target system.
2853 We hope to make this the default in a future release.
2855 * Documentation improvements
2857 There's new internal documentation on how to modify GDB, and how to
2858 produce clean changes to the code. We implore people to read it
2859 before submitting changes.
2861 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2862 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2863 `info' files are also provided. To build `info' files from scratch,
2864 you will need the latest `makeinfo' release, which will be available in
2865 a future texinfo-X.Y release.
2867 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2868 We're not sure exactly which versions have this problem, but it has
2869 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2870 or better. If that isn't possible, there is a patch in
2871 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2872 around this problem.
2876 GDB now supports array constants that can be used in expressions typed in by
2877 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2878 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2881 The new directory `gdb/sparclite' contains a program that demonstrates
2882 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2884 * New native hosts supported
2886 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2887 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2889 * New targets supported
2891 AMD 29k family via UDI a29k-amd-udi or udi29k
2893 * New file formats supported
2895 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2896 HPUX core files, and SCO 3.2v2 core files.
2900 Attaching to processes now works again; thanks for the many bug reports.
2902 We have also stomped on a bunch of core dumps caused by
2903 printf_filtered("%s") problems.
2905 We eliminated a copyright problem on the rpc and ptrace header files
2906 for VxWorks, which was discovered at the last minute during the 4.7
2907 release. You should now be able to build a VxWorks GDB.
2909 You can now interrupt gdb while an attached process is running. This
2910 will cause the attached process to stop, and give control back to GDB.
2912 We fixed problems caused by using too many file descriptors
2913 for reading symbols from object files and libraries. This was
2914 especially a problem for programs that used many (~100) shared
2917 The `step' command now only enters a subroutine if there is line number
2918 information for the subroutine. Otherwise it acts like the `next'
2919 command. Previously, `step' would enter subroutines if there was
2920 any debugging information about the routine. This avoids problems
2921 when using `cc -g1' on MIPS machines.
2923 * Internal improvements
2925 GDB's internal interfaces have been improved to make it easier to support
2926 debugging of multiple languages in the future.
2928 GDB now uses a common structure for symbol information internally.
2929 Minimal symbols (derived from linkage symbols in object files), partial
2930 symbols (from a quick scan of debug information), and full symbols
2931 contain a common subset of information, making it easier to write
2932 shared code that handles any of them.
2934 * New command line options
2936 We now accept --silent as an alias for --quiet.
2940 The memory-mapped-malloc library is now licensed under the GNU Library
2941 General Public License.
2943 *** Changes in GDB-4.7:
2945 * Host/native/target split
2947 GDB has had some major internal surgery to untangle the support for
2948 hosts and remote targets. Now, when you configure GDB for a remote
2949 target, it will no longer load in all of the support for debugging
2950 local programs on the host. When fully completed and tested, this will
2951 ensure that arbitrary host/target combinations are possible.
2953 The primary conceptual shift is to separate the non-portable code in
2954 GDB into three categories. Host specific code is required any time GDB
2955 is compiled on that host, regardless of the target. Target specific
2956 code relates to the peculiarities of the target, but can be compiled on
2957 any host. Native specific code is everything else: it can only be
2958 built when the host and target are the same system. Child process
2959 handling and core file support are two common `native' examples.
2961 GDB's use of /proc for controlling Unix child processes is now cleaner.
2962 It has been split out into a single module under the `target_ops' vector,
2963 plus two native-dependent functions for each system that uses /proc.
2965 * New hosts supported
2967 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2968 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2969 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2971 * New targets supported
2973 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2974 68030 and CPU32 m68030-*-*, m68332-*-*
2976 * New native hosts supported
2978 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2979 (386bsd is not well tested yet)
2980 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2982 * New file formats supported
2984 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2985 supports reading of `a.out.adobe' object files, which are an a.out
2986 format extended with minimal information about multiple sections.
2990 `show copying' is the same as the old `info copying'.
2991 `show warranty' is the same as `info warrantee'.
2992 These were renamed for consistency. The old commands continue to work.
2994 `info handle' is a new alias for `info signals'.
2996 You can now define pre-command hooks, which attach arbitrary command
2997 scripts to any command. The commands in the hook will be executed
2998 prior to the user's command. You can also create a hook which will be
2999 executed whenever the program stops. See gdb.texinfo.
3003 We now deal with Cfront style name mangling, and can even extract type
3004 info from mangled symbols. GDB can automatically figure out which
3005 symbol mangling style your C++ compiler uses.
3007 Calling of methods and virtual functions has been improved as well.
3011 The crash that occured when debugging Sun Ansi-C compiled binaries is
3012 fixed. This was due to mishandling of the extra N_SO stabs output
3015 We also finally got Ultrix 4.2 running in house, and fixed core file
3016 support, with help from a dozen people on the net.
3018 John M. Farrell discovered that the reason that single-stepping was so
3019 slow on all of the Mips based platforms (primarily SGI and DEC) was
3020 that we were trying to demangle and lookup a symbol used for internal
3021 purposes on every instruction that was being stepped through. Changing
3022 the name of that symbol so that it couldn't be mistaken for a C++
3023 mangled symbol sped things up a great deal.
3025 Rich Pixley sped up symbol lookups in general by getting much smarter
3026 about when C++ symbol mangling is necessary. This should make symbol
3027 completion (TAB on the command line) much faster. It's not as fast as
3028 we'd like, but it's significantly faster than gdb-4.6.
3032 A new user controllable variable 'call_scratch_address' can
3033 specify the location of a scratch area to be used when GDB
3034 calls a function in the target. This is necessary because the
3035 usual method of putting the scratch area on the stack does not work
3036 in systems that have separate instruction and data spaces.
3038 We integrated changes to support the 29k UDI (Universal Debugger
3039 Interface), but discovered at the last minute that we didn't have all
3040 of the appropriate copyright paperwork. We are working with AMD to
3041 resolve this, and hope to have it available soon.
3045 We have sped up the remote serial line protocol, especially for targets
3046 with lots of registers. It now supports a new `expedited status' ('T')
3047 message which can be used in place of the existing 'S' status message.
3048 This allows the remote stub to send only the registers that GDB
3049 needs to make a quick decision about single-stepping or conditional
3050 breakpoints, eliminating the need to fetch the entire register set for
3051 each instruction being stepped through.
3053 The GDB remote serial protocol now implements a write-through cache for
3054 registers, only re-reading the registers if the target has run.
3056 There is also a new remote serial stub for SPARC processors. You can
3057 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3058 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3059 processor with a serial port.
3063 Configure.in files have become much easier to read and modify. A new
3064 `table driven' format makes it more obvious what configurations are
3065 supported, and what files each one uses.
3069 There is a new opcodes library which will eventually contain all of the
3070 disassembly routines and opcode tables. At present, it only contains
3071 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3072 disassembler (binutils/objdump) to share these routines.
3074 The libiberty library is now copylefted under the GNU Library General
3075 Public License. This allows more liberal use, and was done so libg++
3076 can use it. This makes no difference to GDB, since the Library License
3077 grants all the rights from the General Public License.
3081 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3082 reference to the stabs symbol info used by the debugger. It is (as far
3083 as we know) the only published document on this fascinating topic. We
3084 encourage you to read it, compare it to the stabs information on your
3085 system, and send improvements on the document in general (to
3086 bug-gdb@prep.ai.mit.edu).
3088 And, of course, many bugs have been fixed.
3091 *** Changes in GDB-4.6:
3093 * Better support for C++ function names
3095 GDB now accepts as input the "demangled form" of C++ overloaded function
3096 names and member function names, and can do command completion on such names
3097 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3098 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3099 Make use of command completion, it is your friend.
3101 GDB also now accepts a variety of C++ mangled symbol formats. They are
3102 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3103 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3104 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3105 for the list of formats.
3107 * G++ symbol mangling problem
3109 Recent versions of gcc have a bug in how they emit debugging information for
3110 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3111 directory) can be applied to gcc to fix the problem. Alternatively, if you
3112 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3113 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3114 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3117 * New 'maintenance' command
3119 All of the commands related to hacking GDB internals have been moved out of
3120 the main command set, and now live behind the 'maintenance' command. This
3121 can also be abbreviated as 'mt'. The following changes were made:
3123 dump-me -> maintenance dump-me
3124 info all-breakpoints -> maintenance info breakpoints
3125 printmsyms -> maintenance print msyms
3126 printobjfiles -> maintenance print objfiles
3127 printpsyms -> maintenance print psymbols
3128 printsyms -> maintenance print symbols
3130 The following commands are new:
3132 maintenance demangle Call internal GDB demangler routine to
3133 demangle a C++ link name and prints the result.
3134 maintenance print type Print a type chain for a given symbol
3136 * Change to .gdbinit file processing
3138 We now read the $HOME/.gdbinit file before processing the argv arguments
3139 (e.g. reading symbol files or core files). This allows global parameters to
3140 be set, which will apply during the symbol reading. The ./.gdbinit is still
3141 read after argv processing.
3143 * New hosts supported
3145 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3147 GNU/Linux support i386-unknown-linux or linux
3149 We are also including code to support the HP/PA running BSD and HPUX. This
3150 is almost guaranteed not to work, as we didn't have time to test or build it
3151 for this release. We are including it so that the more adventurous (or
3152 masochistic) of you can play with it. We also had major problems with the
3153 fact that the compiler that we got from HP doesn't support the -g option.
3156 * New targets supported
3158 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3160 * More smarts about finding #include files
3162 GDB now remembers the compilation directory for all include files, and for
3163 all files from which C is generated (like yacc and lex sources). This
3164 greatly improves GDB's ability to find yacc/lex sources, and include files,
3165 especially if you are debugging your program from a directory different from
3166 the one that contains your sources.
3168 We also fixed a bug which caused difficulty with listing and setting
3169 breakpoints in include files which contain C code. (In the past, you had to
3170 try twice in order to list an include file that you hadn't looked at before.)
3172 * Interesting infernals change
3174 GDB now deals with arbitrary numbers of sections, where the symbols for each
3175 section must be relocated relative to that section's landing place in the
3176 target's address space. This work was needed to support ELF with embedded
3177 stabs used by Solaris-2.0.
3179 * Bug fixes (of course!)
3181 There have been loads of fixes for the following things:
3182 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3183 i960, stabs, DOS(GO32), procfs, etc...
3185 See the ChangeLog for details.
3187 *** Changes in GDB-4.5:
3189 * New machines supported (host and target)
3191 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3193 SGI Irix-4.x mips-sgi-irix4 or iris4
3195 * New malloc package
3197 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3198 Mmalloc is capable of handling mutiple heaps of memory. It is also
3199 capable of saving a heap to a file, and then mapping it back in later.
3200 This can be used to greatly speedup the startup of GDB by using a
3201 pre-parsed symbol table which lives in a mmalloc managed heap. For
3202 more details, please read mmalloc/mmalloc.texi.
3206 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3207 'help info proc' for details.
3209 * MIPS ecoff symbol table format
3211 The code that reads MIPS symbol table format is now supported on all hosts.
3212 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3215 * File name changes for MS-DOS
3217 Many files in the config directories have been renamed to make it easier to
3218 support GDB on MS-DOSe systems (which have very restrictive file name
3219 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3220 environment) is close to working but has some remaining problems. Note
3221 that debugging of DOS programs is not supported, due to limitations
3222 in the ``operating system'', but it can be used to host cross-debugging.
3224 * Cross byte order fixes
3226 Many fixes have been made to support cross debugging of Sparc and MIPS
3227 targets from hosts whose byte order differs.
3229 * New -mapped and -readnow options
3231 If memory-mapped files are available on your system through the 'mmap'
3232 system call, you can use the -mapped option on the `file' or
3233 `symbol-file' commands to cause GDB to write the symbols from your
3234 program into a reusable file. If the program you are debugging is
3235 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3236 Future GDB debugging sessions will notice the presence of this file,
3237 and will quickly map in symbol information from it, rather than reading
3238 the symbol table from the executable program. Using the '-mapped'
3239 option in a GDB `file' or `symbol-file' command has the same effect as
3240 starting GDB with the '-mapped' command-line option.
3242 You can cause GDB to read the entire symbol table immediately by using
3243 the '-readnow' option with any of the commands that load symbol table
3244 information (or on the GDB command line). This makes the command
3245 slower, but makes future operations faster.
3247 The -mapped and -readnow options are typically combined in order to
3248 build a `fred.syms' file that contains complete symbol information.
3249 A simple GDB invocation to do nothing but build a `.syms' file for future
3252 gdb -batch -nx -mapped -readnow programname
3254 The `.syms' file is specific to the host machine on which GDB is run.
3255 It holds an exact image of GDB's internal symbol table. It cannot be
3256 shared across multiple host platforms.
3258 * longjmp() handling
3260 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3261 siglongjmp() without losing control. This feature has not yet been ported to
3262 all systems. It currently works on many 386 platforms, all MIPS-based
3263 platforms (SGI, DECstation, etc), and Sun3/4.
3267 Preliminary work has been put in to support the new Solaris OS from Sun. At
3268 this time, it can control and debug processes, but it is not capable of
3273 As always, many many bug fixes. The major areas were with g++, and mipsread.
3274 People using the MIPS-based platforms should experience fewer mysterious
3275 crashes and trashed symbol tables.
3277 *** Changes in GDB-4.4:
3279 * New machines supported (host and target)
3281 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3283 BSD Reno on Vax vax-dec-bsd
3284 Ultrix on Vax vax-dec-ultrix
3286 * New machines supported (target)
3288 AMD 29000 embedded, using EBMON a29k-none-none
3292 GDB continues to improve its handling of C++. `References' work better.
3293 The demangler has also been improved, and now deals with symbols mangled as
3294 per the Annotated C++ Reference Guide.
3296 GDB also now handles `stabs' symbol information embedded in MIPS
3297 `ecoff' symbol tables. Since the ecoff format was not easily
3298 extensible to handle new languages such as C++, this appeared to be a
3299 good way to put C++ debugging info into MIPS binaries. This option
3300 will be supported in the GNU C compiler, version 2, when it is
3303 * New features for SVR4
3305 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3306 shared libraries. Debugging dynamically linked programs should present
3307 only minor differences from debugging statically linked programs.
3309 The `info proc' command will print out information about any process
3310 on an SVR4 system (including the one you are debugging). At the moment,
3311 it prints the address mappings of the process.
3313 If you bring up GDB on another SVR4 system, please send mail to
3314 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3316 * Better dynamic linking support in SunOS
3318 Reading symbols from shared libraries which contain debugging symbols
3319 now works properly. However, there remain issues such as automatic
3320 skipping of `transfer vector' code during function calls, which
3321 make it harder to debug code in a shared library, than to debug the
3322 same code linked statically.
3326 GDB is now using the latest `getopt' routines from the FSF. This
3327 version accepts the -- prefix for options with long names. GDB will
3328 continue to accept the old forms (-option and +option) as well.
3329 Various single letter abbreviations for options have been explicity
3330 added to the option table so that they won't get overshadowed in the
3331 future by other options that begin with the same letter.
3335 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3336 Many assorted bugs have been handled. Many more remain to be handled.
3337 See the various ChangeLog files (primarily in gdb and bfd) for details.
3340 *** Changes in GDB-4.3:
3342 * New machines supported (host and target)
3344 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3345 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3346 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3348 * Almost SCO Unix support
3350 We had hoped to support:
3351 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3352 (except for core file support), but we discovered very late in the release
3353 that it has problems with process groups that render gdb unusable. Sorry
3354 about that. I encourage people to fix it and post the fixes.
3356 * Preliminary ELF and DWARF support
3358 GDB can read ELF object files on System V Release 4, and can handle
3359 debugging records for C, in DWARF format, in ELF files. This support
3360 is preliminary. If you bring up GDB on another SVR4 system, please
3361 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3366 GDB now uses the latest `readline' library. One user-visible change
3367 is that two tabs will list possible command completions, which previously
3368 required typing M-? (meta-question mark, or ESC ?).
3372 The `stepi' bug that many of you noticed has been squashed.
3373 Many bugs in C++ have been handled. Many more remain to be handled.
3374 See the various ChangeLog files (primarily in gdb and bfd) for details.
3376 * State of the MIPS world (in case you wondered):
3378 GDB can understand the symbol tables emitted by the compilers
3379 supplied by most vendors of MIPS-based machines, including DEC. These
3380 symbol tables are in a format that essentially nobody else uses.
3382 Some versions of gcc come with an assembler post-processor called
3383 mips-tfile. This program is required if you want to do source-level
3384 debugging of gcc-compiled programs. I believe FSF does not ship
3385 mips-tfile with gcc version 1, but it will eventually come with gcc
3388 Debugging of g++ output remains a problem. g++ version 1.xx does not
3389 really support it at all. (If you're lucky, you should be able to get
3390 line numbers and stack traces to work, but no parameters or local
3391 variables.) With some work it should be possible to improve the
3394 When gcc version 2 is released, you will have somewhat better luck.
3395 However, even then you will get confusing results for inheritance and
3398 We will eventually provide full debugging of g++ output on
3399 DECstations. This will probably involve some kind of stabs-in-ecoff
3400 encapulation, but the details have not been worked out yet.
3403 *** Changes in GDB-4.2:
3405 * Improved configuration
3407 Only one copy of `configure' exists now, and it is not self-modifying.
3408 Porting BFD is simpler.
3412 The `step' and `next' commands now only stop at the first instruction
3413 of a source line. This prevents the multiple stops that used to occur
3414 in switch statements, for-loops, etc. `Step' continues to stop if a
3415 function that has debugging information is called within the line.
3419 Lots of small bugs fixed. More remain.
3421 * New host supported (not target)
3423 Intel 386 PC clone running Mach i386-none-mach
3426 *** Changes in GDB-4.1:
3428 * Multiple source language support
3430 GDB now has internal scaffolding to handle several source languages.
3431 It determines the type of each source file from its filename extension,
3432 and will switch expression parsing and number formatting to match the
3433 language of the function in the currently selected stack frame.
3434 You can also specifically set the language to be used, with
3435 `set language c' or `set language modula-2'.
3439 GDB now has preliminary support for the GNU Modula-2 compiler,
3440 currently under development at the State University of New York at
3441 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3442 continue through the fall of 1991 and into 1992.
3444 Other Modula-2 compilers are currently not supported, and attempting to
3445 debug programs compiled with them will likely result in an error as the
3446 symbol table is read. Feel free to work on it, though!
3448 There are hooks in GDB for strict type checking and range checking,
3449 in the `Modula-2 philosophy', but they do not currently work.
3453 GDB can now write to executable and core files (e.g. patch
3454 a variable's value). You must turn this switch on, specify
3455 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3456 by assigning a new value to a variable. Modifications take
3459 * Automatic SunOS shared library reading
3461 When you run your program, GDB automatically determines where its
3462 shared libraries (if any) have been loaded, and reads their symbols.
3463 The `share' command is no longer needed. This also works when
3464 examining core files.
3468 You can specify the number of lines that the `list' command shows.
3471 * New machines supported (host and target)
3473 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3474 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3475 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3477 * New hosts supported (not targets)
3479 IBM RT/PC: romp-ibm-aix or rtpc
3481 * New targets supported (not hosts)
3483 AMD 29000 embedded with COFF a29k-none-coff
3484 AMD 29000 embedded with a.out a29k-none-aout
3485 Ultracomputer remote kernel debug a29k-nyu-kern
3487 * New remote interfaces
3493 *** Changes in GDB-4.0:
3497 Wide output is wrapped at good places to make the output more readable.
3499 Gdb now supports cross-debugging from a host machine of one type to a
3500 target machine of another type. Communication with the target system
3501 is over serial lines. The ``target'' command handles connecting to the
3502 remote system; the ``load'' command will download a program into the
3503 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3504 also supports debugging of realtime processes running under VxWorks,
3505 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3506 stub on the target system.
3508 New CPUs supported include the AMD 29000 and Intel 960.
3510 GDB now reads object files and symbol tables via a ``binary file''
3511 library, which allows a single copy of GDB to debug programs of multiple
3512 object file types such as a.out and coff.
3514 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3515 refcard.dvi and refcard.ps are available to format it).
3518 * Control-Variable user interface simplified
3520 All variables that control the operation of the debugger can be set
3521 by the ``set'' command, and displayed by the ``show'' command.
3523 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3524 ``Show prompt'' produces the response:
3525 Gdb's prompt is new-gdb=>.
3527 What follows are the NEW set commands. The command ``help set'' will
3528 print a complete list of old and new set commands. ``help set FOO''
3529 will give a longer description of the variable FOO. ``show'' will show
3530 all of the variable descriptions and their current settings.
3532 confirm on/off: Enables warning questions for operations that are
3533 hard to recover from, e.g. rerunning the program while
3534 it is already running. Default is ON.
3536 editing on/off: Enables EMACS style command line editing
3537 of input. Previous lines can be recalled with
3538 control-P, the current line can be edited with control-B,
3539 you can search for commands with control-R, etc.
3542 history filename NAME: NAME is where the gdb command history
3543 will be stored. The default is .gdb_history,
3544 or the value of the environment variable
3547 history size N: The size, in commands, of the command history. The
3548 default is 256, or the value of the environment variable
3551 history save on/off: If this value is set to ON, the history file will
3552 be saved after exiting gdb. If set to OFF, the
3553 file will not be saved. The default is OFF.
3555 history expansion on/off: If this value is set to ON, then csh-like
3556 history expansion will be performed on
3557 command line input. The default is OFF.
3559 radix N: Sets the default radix for input and output. It can be set
3560 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3561 in the current radix, so "set radix 10" is always a no-op.
3563 height N: This integer value is the number of lines on a page. Default
3564 is 24, the current `stty rows'' setting, or the ``li#''
3565 setting from the termcap entry matching the environment
3568 width N: This integer value is the number of characters on a line.
3569 Default is 80, the current `stty cols'' setting, or the ``co#''
3570 setting from the termcap entry matching the environment
3573 Note: ``set screensize'' is obsolete. Use ``set height'' and
3574 ``set width'' instead.
3576 print address on/off: Print memory addresses in various command displays,
3577 such as stack traces and structure values. Gdb looks
3578 more ``symbolic'' if you turn this off; it looks more
3579 ``machine level'' with it on. Default is ON.
3581 print array on/off: Prettyprint arrays. New convenient format! Default
3584 print demangle on/off: Print C++ symbols in "source" form if on,
3587 print asm-demangle on/off: Same, for assembler level printouts
3590 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3593 * Support for Epoch Environment.
3595 The epoch environment is a version of Emacs v18 with windowing. One
3596 new command, ``inspect'', is identical to ``print'', except that if you
3597 are running in the epoch environment, the value is printed in its own
3601 * Support for Shared Libraries
3603 GDB can now debug programs and core files that use SunOS shared libraries.
3604 Symbols from a shared library cannot be referenced
3605 before the shared library has been linked with the program (this
3606 happens after you type ``run'' and before the function main() is entered).
3607 At any time after this linking (including when examining core files
3608 from dynamically linked programs), gdb reads the symbols from each
3609 shared library when you type the ``sharedlibrary'' command.
3610 It can be abbreviated ``share''.
3612 sharedlibrary REGEXP: Load shared object library symbols for files
3613 matching a unix regular expression. No argument
3614 indicates to load symbols for all shared libraries.
3616 info sharedlibrary: Status of loaded shared libraries.
3621 A watchpoint stops execution of a program whenever the value of an
3622 expression changes. Checking for this slows down execution
3623 tremendously whenever you are in the scope of the expression, but is
3624 quite useful for catching tough ``bit-spreader'' or pointer misuse
3625 problems. Some machines such as the 386 have hardware for doing this
3626 more quickly, and future versions of gdb will use this hardware.
3628 watch EXP: Set a watchpoint (breakpoint) for an expression.
3630 info watchpoints: Information about your watchpoints.
3632 delete N: Deletes watchpoint number N (same as breakpoints).
3633 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3634 enable N: Re-enables watchpoint number N (same as breakpoints).
3637 * C++ multiple inheritance
3639 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3642 * C++ exception handling
3644 Gdb now supports limited C++ exception handling. Besides the existing
3645 ability to breakpoint on an exception handler, gdb can breakpoint on
3646 the raising of an exception (before the stack is peeled back to the
3649 catch FOO: If there is a FOO exception handler in the dynamic scope,
3650 set a breakpoint to catch exceptions which may be raised there.
3651 Multiple exceptions (``catch foo bar baz'') may be caught.
3653 info catch: Lists all exceptions which may be caught in the
3654 current stack frame.
3657 * Minor command changes
3659 The command ``call func (arg, arg, ...)'' now acts like the print
3660 command, except it does not print or save a value if the function's result
3661 is void. This is similar to dbx usage.
3663 The ``up'' and ``down'' commands now always print the frame they end up
3664 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3665 frames without printing.
3667 * New directory command
3669 'dir' now adds directories to the FRONT of the source search path.
3670 The path starts off empty. Source files that contain debug information
3671 about the directory in which they were compiled can be found even
3672 with an empty path; Sun CC and GCC include this information. If GDB can't
3673 find your source file in the current directory, type "dir .".
3675 * Configuring GDB for compilation
3677 For normal use, type ``./configure host''. See README or gdb.texinfo
3680 GDB now handles cross debugging. If you are remotely debugging between
3681 two different machines, type ``./configure host -target=targ''.
3682 Host is the machine where GDB will run; targ is the machine
3683 where the program that you are debugging will run.