1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
7 feature is available with a native GDB running on kernel version
10 * GDB now has support for multi-byte and wide character sets on the
11 target. Strings whose character type is wchar_t, char16_t, or
12 char32_t are now correctly printed. GDB supports wide- and unicode-
13 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
14 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
15 `printf'. This feature requires iconv to work properly; if your
16 system does not have a working iconv, GDB can use GNU libiconv. See
17 the installation instructions for more information.
19 * GDB now supports automatic retrieval of shared library files from
20 remote targets. To use this feature, specify a system root that begins
21 with the `remote:' prefix, either via the `set sysroot' command or via
22 the `--with-sysroot' configure-time option.
24 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
25 now complete on file names.
27 * When completing in expressions, gdb will attempt to limit
28 completions to allowable structure or union fields, where appropriate.
29 For instance, consider:
31 # struct example { int f1; double f2; };
32 # struct example variable;
35 If the user types TAB at the end of this command line, the available
36 completions will be "f1" and "f2".
38 * GDB now supports the token-splicing (##) and stringification (#)
39 operators when expanding macros. It also supports variable-arity
42 * GDB now supports inspecting extra signal information, exported by
43 the new $_siginfo convenience variable. The feature is currently
44 implemented on linux ARM, i386 and amd64.
49 Search memory for a sequence of bytes.
52 Turn off `+'/`-' protocol acknowledgments to permit more efficient
53 operation over reliable transport links. Use of this packet is
54 controlled by the `set remote noack-packet' command.
57 Kill the process with the specified process ID. Use this in preference
58 to `k' when multiprocess protocol extensions are supported.
61 Obtains additional operating system information
65 Read or write additional signal information.
67 * Removed remote protocol undocumented extension
69 An undocumented extension to the remote protocol's `S' stop reply
70 packet that permited the stub to pass a process id was removed.
71 Remote servers should use the `T' stop reply packet instead.
73 * The "disassemble" command now supports an optional /m modifier to print mixed
76 * GDB now supports multiple function calling conventions according to the
77 DWARF-2 DW_AT_calling_convention function attribute.
79 * The SH target utilizes the aforementioned change to distinguish between gcc
80 and Renesas calling convention. It also adds the new CLI commands
81 `set/show sh calling-convention'.
83 * GDB can now read compressed debug sections, as produced by GNU gold
84 with the --compress-debug-sections=zlib flag.
86 * 64-bit core files are now supported on AIX.
88 * Thread switching is now supported on Tru64.
90 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
91 which will be allocated using malloc later in program execution.
93 * The qXfer:libraries:read remote procotol packet now allows passing a
94 list of section offsets.
96 * On GNU/Linux, GDB can now attach to stopped processes. Several race
97 conditions handling signals delivered during attach or thread creation
100 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
101 From the user's standpoint, all unqualified instances of True and False
102 are treated as the standard definitions, regardless of context.
104 * GDB now parses C++ symbol and type names more flexibly. For
107 template<typename T> class C { };
110 GDB will now correctly handle all of:
112 ptype C<char const *>
114 ptype C<const char *>
117 * New features in the GDB remote stub, gdbserver
119 - The "--wrapper" command-line argument tells gdbserver to use a
120 wrapper program to launch programs for debugging.
122 - On PowerPC and S/390 targets, it is now possible to use a single
123 gdbserver executable to debug both 32-bit and 64-bit programs.
124 (This requires gdbserver itself to be built as a 64-bit executable.)
126 - gdbserver uses the new noack protocol mode for TCP connections to
127 reduce communications latency, if also supported and enabled in GDB.
129 - Support for the sparc64-linux-gnu target is now included in
134 GDB now has support for scripting using Python. Whether this is
135 available is determined at configure time.
137 New GDB commands can now be written in Python.
139 * Ada tasking support
141 Ada tasks can now be inspected in GDB. The following commands have
145 Print the list of Ada tasks.
147 Print detailed information about task number N.
149 Print the task number of the current task.
151 Switch the context of debugging to task number N.
153 * Support for user-defined prefixed commands. The "define" command can
154 add new commands to existing prefixes, e.g. "target".
156 * New commands (for set/show, see "New options" below)
158 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
160 Search memory for a sequence of bytes.
162 maint set python print-stack
163 maint show python print-stack
164 Show a stack trace when an error is encountered in a Python script.
167 Invoke CODE by passing it to the Python interpreter.
172 These allow macros to be defined, undefined, and listed
176 Show operating system information about processes.
180 set sh calling-convention
181 show sh calling-convention
182 Control the calling convention used when calling SH target functions.
184 set print symbol-loading
185 show print symbol-loading
186 Control printing of symbol loading messages.
190 Control display of timestamps with GDB debugging output.
192 set disassemble-next-line
193 show disassemble-next-line
194 Control display of disassembled source lines or instructions when
197 set remote noack-packet
198 show remote noack-packet
199 Set/show the use of remote protocol QStartNoAckMode packet. See above
200 under "New remote packets."
202 set remote query-attached-packet
203 show remote query-attached-packet
204 Control use of remote protocol `qAttached' (query-attached) packet.
206 set remote read-siginfo-object
207 show remote read-siginfo-object
208 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
211 set remote write-siginfo-object
212 show remote write-siginfo-object
213 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
216 set displaced-stepping
217 show displaced-stepping
218 Control displaced stepping mode. Displaced stepping is a way to
219 single-step over breakpoints without removing them from the debuggee.
220 Also known as "out-of-line single-stepping".
224 Control display of debugging info for displaced stepping.
226 maint set internal-error
227 maint show internal-error
228 Control what GDB does when an internal error is detected.
230 maint set internal-warning
231 maint show internal-warning
232 Control what GDB does when an internal warning is detected.
237 Use a wrapper program to launch programs for debugging.
239 set multiple-symbols (all|ask|cancel)
240 show multiple-symbols
241 The value of this variable can be changed to adjust the debugger behavior
242 when an expression or a breakpoint location contains an ambiguous symbol
243 name (an overloaded function name, for instance).
245 set breakpoint always-inserted
246 show breakpoint always-inserted
247 Keep breakpoints always inserted in the target, as opposed to inserting
248 them when resuming the target, and removing them when the target stops.
249 This option can improve debugger performance on slow remote targets.
251 set arm fallback-mode (arm|thumb|auto)
252 show arm fallback-mode
253 set arm force-mode (arm|thumb|auto)
255 These commands control how ARM GDB determines whether instructions
256 are ARM or Thumb. The default for both settings is auto, which uses
257 the current CPSR value for instructions without symbols; previous
258 versions of GDB behaved as if "set arm fallback-mode arm".
260 set disable-randomization
261 show disable-randomization
262 Standalone programs run with the virtual address space randomization enabled
263 by default on some platforms. This option keeps the addresses stable across
264 multiple debugging sessions.
268 Control whether other threads are stopped or not when some thread hits
273 Requests that asynchronous execution is enabled in the target, if available.
274 In this case, it's possible to resume target in the background, and interact
275 with GDB while the target is running. "show target-async" displays the
276 current state of asynchronous execution of the target.
278 set target-wide-charset
279 show target-wide-charset
280 The target-wide-charset is the name of the character set that GDB
281 uses when printing characters whose type is wchar_t.
283 set tcp auto-retry (on|off)
285 set tcp connect-timeout
286 show tcp connect-timeout
287 These commands allow GDB to retry failed TCP connections to a remote stub
288 with a specified timeout period; this is useful if the stub is launched
289 in parallel with GDB but may not be ready to accept connections immediately.
291 * New native configurations
293 x86/x86_64 Darwin i[34567]86-*-darwin*
295 x86_64 MinGW x86_64-*-mingw*
299 x86 DICOS i[34567]86-*-dicos*
300 x86_64 DICOS x86_64-*-dicos*
302 * The GDB remote stub, gdbserver, now supports x86 Windows CE
303 (mingw32ce) debugging.
309 These commands were actually not implemented on any target.
311 *** Changes in GDB 6.8
313 * New native configurations
315 NetBSD/hppa hppa*-*netbsd*
316 Xtensa GNU/Linux xtensa*-*-linux*
320 NetBSD/hppa hppa*-*-netbsd*
321 Xtensa GNU/Lunux xtensa*-*-linux*
323 * Change in command line behavior -- corefiles vs. process ids.
325 When the '-p NUMBER' or '--pid NUMBER' options are used, and
326 attaching to process NUMBER fails, GDB no longer attempts to open a
327 core file named NUMBER. Attaching to a program using the -c option
328 is no longer supported. Instead, use the '-p' or '--pid' options.
330 * GDB can now be built as a native debugger for debugging Windows x86
331 (mingw32) Portable Executable (PE) programs.
333 * Pending breakpoints no longer change their number when their address
336 * GDB now supports breakpoints with multiple locations,
337 including breakpoints on C++ constructors, inside C++ templates,
338 and in inlined functions.
340 * GDB's ability to debug optimized code has been improved. GDB more
341 accurately identifies function bodies and lexical blocks that occupy
342 more than one contiguous range of addresses.
344 * Target descriptions can now describe registers for PowerPC.
346 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
347 registers on PowerPC targets.
349 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
350 targets even when the libthread_db library is not available.
352 * The GDB remote stub, gdbserver, now supports the new file transfer
353 commands (remote put, remote get, and remote delete).
355 * The GDB remote stub, gdbserver, now supports run and attach in
356 extended-remote mode.
358 * hppa*64*-*-hpux11* target broken
359 The debugger is unable to start a program and fails with the following
360 error: "Error trying to get information about dynamic linker".
361 The gdb-6.7 release is also affected.
363 * GDB now supports the --enable-targets= configure option to allow
364 building a single GDB executable that supports multiple remote
365 target architectures.
367 * GDB now supports debugging C and C++ programs which use the
368 Decimal Floating Point extension. In addition, the PowerPC target
369 now has a set of pseudo-registers to inspect decimal float values
370 stored in two consecutive float registers.
372 * The -break-insert MI command can optionally create pending
375 * Improved support for debugging Ada
376 Many improvements to the Ada language support have been made. These
378 - Better support for Ada2005 interface types
379 - Improved handling of arrays and slices in general
380 - Better support for Taft-amendment types
381 - The '{type} ADDRESS' expression is now allowed on the left hand-side
383 - Improved command completion in Ada
386 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
391 set print frame-arguments (all|scalars|none)
392 show print frame-arguments
393 The value of this variable can be changed to control which argument
394 values should be printed by the debugger when displaying a frame.
399 Transfer files to and from a remote target, and delete remote files.
406 Transfer files to and from a remote target, and delete remote files.
415 Open, close, read, write, and delete files on the remote system.
418 Attach to an existing process on the remote system, in extended-remote
422 Run a new process on the remote system, in extended-remote mode.
424 *** Changes in GDB 6.7
426 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
427 bfd, libiberty and opcodes, as revealed by static analysis donated by
428 Coverity, Inc. (http://scan.coverity.com).
430 * When looking up multiply-defined global symbols, GDB will now prefer the
431 symbol definition in the current shared library if it was built using the
432 -Bsymbolic linker option.
434 * When the Text User Interface (TUI) is not configured, GDB will now
435 recognize the -tui command-line option and print a message that the TUI
438 * The GDB remote stub, gdbserver, now has lower overhead for high
439 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
441 * GDB for MIPS targets now autodetects whether a remote target provides
442 32-bit or 64-bit register values.
444 * Support for C++ member pointers has been improved.
446 * GDB now understands XML target descriptions, which specify the
447 target's overall architecture. GDB can read a description from
448 a local file or over the remote serial protocol.
450 * Vectors of single-byte data use a new integer type which is not
451 automatically displayed as character or string data.
453 * The /s format now works with the print command. It displays
454 arrays of single-byte integers and pointers to single-byte integers
457 * Target descriptions can now describe target-specific registers,
458 for architectures which have implemented the support (currently
459 only ARM, M68K, and MIPS).
461 * GDB and the GDB remote stub, gdbserver, now support the XScale
464 * The GDB remote stub, gdbserver, has been updated to support
465 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
466 has been rewritten to use the standard GDB remote protocol.
468 * GDB can now step into C++ functions which are called through thunks.
470 * GDB for the Cell/B.E. SPU now supports overlay debugging.
472 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
473 layout. It also supports a TextSeg= and DataSeg= response when only
474 segment base addresses (rather than offsets) are available.
476 * The /i format now outputs any trailing branch delay slot instructions
477 immediately following the last instruction within the count specified.
479 * The GDB remote protocol "T" stop reply packet now supports a
480 "library" response. Combined with the new "qXfer:libraries:read"
481 packet, this response allows GDB to debug shared libraries on targets
482 where the operating system manages the list of loaded libraries (e.g.
483 Windows and SymbianOS).
485 * The GDB remote stub, gdbserver, now supports dynamic link libraries
486 (DLLs) on Windows and Windows CE targets.
488 * GDB now supports a faster verification that a .debug file matches its binary
489 according to its build-id signature, if the signature is present.
495 Enable or disable hardware flow control (RTS/CTS) on the serial port
496 when debugging using remote targets.
498 set mem inaccessible-by-default
499 show mem inaccessible-by-default
500 If the target supplies a memory map, for instance via the remote
501 protocol's "qXfer:memory-map:read" packet, setting this variable
502 prevents GDB from accessing memory outside the memory map. This
503 is useful for targets with memory mapped registers or which react
504 badly to accesses of unmapped address space.
506 set breakpoint auto-hw
507 show breakpoint auto-hw
508 If the target supplies a memory map, for instance via the remote
509 protocol's "qXfer:memory-map:read" packet, setting this variable
510 lets GDB use hardware breakpoints automatically for memory regions
511 where it can not use software breakpoints. This covers both the
512 "break" command and internal breakpoints used for other commands
513 including "next" and "finish".
516 catch exception unhandled
517 Stop the program execution when Ada exceptions are raised.
520 Stop the program execution when an Ada assertion failed.
524 Set an alternate system root for target files. This is a more
525 general version of "set solib-absolute-prefix", which is now
526 an alias to "set sysroot".
529 Provide extended SPU facility status information. This set of
530 commands is available only when debugging the Cell/B.E. SPU
533 * New native configurations
535 OpenBSD/sh sh*-*openbsd*
540 Use the specified local file as an XML target description, and do
541 not query the target for its built-in description.
545 OpenBSD/sh sh*-*-openbsd*
546 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
547 Toshiba Media Processor mep-elf
552 Ignore the specified signals; pass them directly to the debugged program
553 without stopping other threads or reporting them to GDB.
556 Read an XML target description from the target, which describes its
561 Read or write contents of an spufs file on the target system. These
562 packets are available only on the Cell/B.E. SPU architecture.
564 qXfer:libraries:read:
565 Report the loaded shared libraries. Combined with new "T" packet
566 response, this packet allows GDB to debug shared libraries on
567 targets where the operating system manages the list of loaded
568 libraries (e.g. Windows and SymbianOS).
572 Support for these obsolete configurations has been removed.
581 i[34567]86-*-netware*
582 i[34567]86-*-sco3.2v5*
583 i[34567]86-*-sco3.2v4*
585 i[34567]86-*-sysv4.2*
588 i[34567]86-*-unixware2*
589 i[34567]86-*-unixware*
598 * Other removed features
605 Various m68k-only ROM monitors.
612 Various Renesas ROM monitors and debugging interfaces for SH and
617 Support for a Macraigor serial interface to on-chip debugging.
618 GDB does not directly support the newer parallel or USB
623 A debug information format. The predecessor to DWARF 2 and
624 DWARF 3, which are still supported.
626 Support for the HP aCC compiler on HP-UX/PA-RISC
628 SOM-encapsulated symbolic debugging information, automatic
629 invocation of pxdb, and the aCC custom C++ ABI. This does not
630 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
631 with aCC can still be debugged on an assembly level.
635 A MIPS-specific format used to describe stack frame layout
636 in debugging information.
640 GDB could work with an older version of Guile to debug
641 the interpreter and Scheme programs running in it.
643 set mips stack-arg-size
644 set mips saved-gpreg-size
646 Use "set mips abi" to control parameter passing for MIPS.
648 *** Changes in GDB 6.6
653 Cell Broadband Engine SPU spu-elf
655 * GDB can now be configured as a cross-debugger targeting native Windows
656 (mingw32) or Cygwin. It can communicate with a remote debugging stub
657 running on a Windows system over TCP/IP to debug Windows programs.
659 * The GDB remote stub, gdbserver, has been updated to support Windows and
660 Cygwin debugging. Both single-threaded and multi-threaded programs are
663 * The "set trust-readonly-sections" command works again. This command was
664 broken in GDB 6.3, 6.4, and 6.5.
666 * The "load" command now supports writing to flash memory, if the remote
667 stub provides the required support.
669 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
670 longer requires symbolic debug information (e.g. DWARF-2).
675 unset substitute-path
677 Manage a list of substitution rules that GDB uses to rewrite the name
678 of the directories where the sources are located. This can be useful
679 for instance when the sources were moved to a different location
680 between compilation and debugging.
684 Print each CLI command as it is executed. Each command is prefixed with
685 a number of `+' symbols representing the nesting depth.
686 The source command now has a `-v' option to enable the same feature.
690 The ARM Demon monitor support (RDP protocol, "target rdp").
692 Kernel Object Display, an embedded debugging feature which only worked with
693 an obsolete version of Cisco IOS.
695 The 'set download-write-size' and 'show download-write-size' commands.
700 Tell a stub about GDB client features, and request remote target features.
701 The first feature implemented is PacketSize, which allows the target to
702 specify the size of packets it can handle - to minimize the number of
703 packets required and improve performance when connected to a remote
707 Fetch an OS auxilliary vector from the remote stub. This packet is a
708 more efficient replacement for qPart:auxv:read.
710 qXfer:memory-map:read:
711 Fetch a memory map from the remote stub, including information about
712 RAM, ROM, and flash memory devices.
717 Erase and program a flash memory device.
719 * Removed remote packets
722 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
723 used it, and only gdbserver implemented it.
725 *** Changes in GDB 6.5
729 Renesas M32C/M16C m32c-elf
731 Morpho Technologies ms1 ms1-elf
735 init-if-undefined Initialize a convenience variable, but
736 only if it doesn't already have a value.
738 The following commands are presently only implemented for native GNU/Linux:
740 checkpoint Save a snapshot of the program state.
742 restart <n> Return the program state to a
743 previously saved state.
745 info checkpoints List currently saved checkpoints.
747 delete-checkpoint <n> Delete a previously saved checkpoint.
749 set|show detach-on-fork Tell gdb whether to detach from a newly
750 forked process, or to keep debugging it.
752 info forks List forks of the user program that
753 are available to be debugged.
755 fork <n> Switch to debugging one of several
756 forks of the user program that are
757 available to be debugged.
759 delete-fork <n> Delete a fork from the list of forks
760 that are available to be debugged (and
761 kill the forked process).
763 detach-fork <n> Delete a fork from the list of forks
764 that are available to be debugged (and
765 allow the process to continue).
769 Morpho Technologies ms2 ms1-elf
771 * Improved Windows host support
773 GDB now builds as a cross debugger hosted on i686-mingw32, including
774 native console support, and remote communications using either
775 network sockets or serial ports.
777 * Improved Modula-2 language support
779 GDB can now print most types in the Modula-2 syntax. This includes:
780 basic types, set types, record types, enumerated types, range types,
781 pointer types and ARRAY types. Procedure var parameters are correctly
782 printed and hexadecimal addresses and character constants are also
783 written in the Modula-2 syntax. Best results can be obtained by using
784 GNU Modula-2 together with the -gdwarf-2 command line option.
788 The ARM rdi-share module.
790 The Netware NLM debug server.
792 *** Changes in GDB 6.4
794 * New native configurations
796 OpenBSD/arm arm*-*-openbsd*
797 OpenBSD/mips64 mips64-*-openbsd*
801 Morpho Technologies ms1 ms1-elf
803 * New command line options
805 --batch-silent As for --batch, but totally silent.
806 --return-child-result The debugger will exist with the same value
807 the child (debugged) program exited with.
808 --eval-command COMMAND, -ex COMMAND
809 Execute a single GDB CLI command. This may be
810 specified multiple times and in conjunction
811 with the --command (-x) option.
813 * Deprecated commands removed
815 The following commands, that were deprecated in 2000, have been
819 set|show arm disassembly-flavor set|show arm disassembler
820 othernames set arm disassembler
821 set|show remotedebug set|show debug remote
822 set|show archdebug set|show debug arch
823 set|show eventdebug set|show debug event
826 * New BSD user-level threads support
828 It is now possible to debug programs using the user-level threads
829 library on OpenBSD and FreeBSD. Currently supported (target)
832 FreeBSD/amd64 x86_64-*-freebsd*
833 FreeBSD/i386 i386-*-freebsd*
834 OpenBSD/i386 i386-*-openbsd*
836 Note that the new kernel threads libraries introduced in FreeBSD 5.x
837 are not yet supported.
839 * New support for Matsushita MN10300 w/sim added
840 (Work in progress). mn10300-elf.
842 * REMOVED configurations and files
844 VxWorks and the XDR protocol *-*-vxworks
845 Motorola MCORE mcore-*-*
846 National Semiconductor NS32000 ns32k-*-*
848 * New "set print array-indexes" command
850 After turning this setting "on", GDB prints the index of each element
851 when displaying arrays. The default is "off" to preserve the previous
854 * VAX floating point support
856 GDB now supports the not-quite-ieee VAX F and D floating point formats.
858 * User-defined command support
860 In addition to using $arg0..$arg9 for argument passing, it is now possible
861 to use $argc to determine now many arguments have been passed. See the
862 section on user-defined commands in the user manual for more information.
864 *** Changes in GDB 6.3:
866 * New command line option
868 GDB now accepts -l followed by a number to set the timeout for remote
871 * GDB works with GCC -feliminate-dwarf2-dups
873 GDB now supports a more compact representation of DWARF-2 debug
874 information using DW_FORM_ref_addr references. These are produced
875 by GCC with the option -feliminate-dwarf2-dups and also by some
876 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
877 to use -feliminate-dwarf2-dups.
879 * Internationalization
881 When supported by the host system, GDB will be built with
882 internationalization (libintl). The task of marking up the sources is
883 continued, we're looking forward to our first translation.
887 Initial support for debugging programs compiled with the GNAT
888 implementation of the Ada programming language has been integrated
889 into GDB. In this release, support is limited to expression evaluation.
891 * New native configurations
893 GNU/Linux/m32r m32r-*-linux-gnu
897 GDB's remote protocol now includes support for the 'p' packet. This
898 packet is used to fetch individual registers from a remote inferior.
900 * END-OF-LIFE registers[] compatibility module
902 GDB's internal register infrastructure has been completely rewritten.
903 The new infrastructure making possible the implementation of key new
904 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
907 GDB 6.3 will be the last release to include the the registers[]
908 compatibility module that allowed out-of-date configurations to
909 continue to work. This change directly impacts the following
921 Unless there is activity to revive these configurations, they will be
922 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
924 * OBSOLETE configurations and files
926 Configurations that have been declared obsolete in this release have
927 been commented out. Unless there is activity to revive these
928 configurations, the next release of GDB will have their sources
938 *** Changes in GDB 6.2.1:
940 * MIPS `break main; run' gave an heuristic-fence-post warning
942 When attempting to run even a simple program, a warning about
943 heuristic-fence-post being hit would be reported. This problem has
946 * MIPS IRIX 'long double' crashed GDB
948 When examining a long double variable, GDB would get a segmentation
949 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
950 IRIX long double values).
954 A bug in the VAX stack code was causing problems with the "next"
955 command. This problem has been fixed.
957 *** Changes in GDB 6.2:
959 * Fix for ``many threads''
961 On GNU/Linux systems that use the NPTL threads library, a program
962 rapidly creating and deleting threads would confuse GDB leading to the
965 ptrace: No such process.
966 thread_db_get_info: cannot get thread info: generic error
968 This problem has been fixed.
970 * "-async" and "-noasync" options removed.
972 Support for the broken "-noasync" option has been removed (it caused
975 * New ``start'' command.
977 This command runs the program until the begining of the main procedure.
979 * New BSD Kernel Data Access Library (libkvm) interface
981 Using ``target kvm'' it is now possible to debug kernel core dumps and
982 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
983 platforms. Currently supported (native-only) configurations are:
985 FreeBSD/amd64 x86_64-*-freebsd*
986 FreeBSD/i386 i?86-*-freebsd*
987 NetBSD/i386 i?86-*-netbsd*
988 NetBSD/m68k m68*-*-netbsd*
989 NetBSD/sparc sparc-*-netbsd*
990 OpenBSD/amd64 x86_64-*-openbsd*
991 OpenBSD/i386 i?86-*-openbsd*
992 OpenBSD/m68k m68*-openbsd*
993 OpenBSD/sparc sparc-*-openbsd*
995 * Signal trampoline code overhauled
997 Many generic problems with GDB's signal handling code have been fixed.
998 These include: backtraces through non-contiguous stacks; recognition
999 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1000 call; backtrace through a signal trampoline; step into and out of
1001 signal handlers; and single-stepping in the signal trampoline.
1003 Please note that kernel bugs are a limiting factor here. These
1004 features have been shown to work on an s390 GNU/Linux system that
1005 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1007 * Cygwin support for DWARF 2 added.
1009 * New native configurations
1011 GNU/Linux/hppa hppa*-*-linux*
1012 OpenBSD/hppa hppa*-*-openbsd*
1013 OpenBSD/m68k m68*-*-openbsd*
1014 OpenBSD/m88k m88*-*-openbsd*
1015 OpenBSD/powerpc powerpc-*-openbsd*
1016 NetBSD/vax vax-*-netbsd*
1017 OpenBSD/vax vax-*-openbsd*
1019 * END-OF-LIFE frame compatibility module
1021 GDB's internal frame infrastructure has been completely rewritten.
1022 The new infrastructure making it possible to support key new features
1023 including DWARF 2 Call Frame Information. To aid in the task of
1024 migrating old configurations to this new infrastructure, a
1025 compatibility module, that allowed old configurations to continue to
1026 work, was also included.
1028 GDB 6.2 will be the last release to include this frame compatibility
1029 module. This change directly impacts the following configurations:
1039 Unless there is activity to revive these configurations, they will be
1040 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1042 * REMOVED configurations and files
1044 Sun 3, running SunOS 3 m68*-*-sunos3*
1045 Sun 3, running SunOS 4 m68*-*-sunos4*
1046 Sun 2, running SunOS 3 m68000-*-sunos3*
1047 Sun 2, running SunOS 4 m68000-*-sunos4*
1048 Motorola 680x0 running LynxOS m68*-*-lynxos*
1049 AT&T 3b1/Unix pc m68*-att-*
1050 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1051 decstation mips-dec-* mips-little-*
1052 riscos mips-*-riscos* mips-*-sysv*
1053 sonymips mips-sony-*
1054 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1056 *** Changes in GDB 6.1.1:
1058 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1060 The TUI (Text-mode User Interface) is now built as part of a default
1061 GDB configuration. It is enabled by either selecting the TUI with the
1062 command line option "-i=tui" or by running the separate "gdbtui"
1063 program. For more information on the TUI, see the manual "Debugging
1066 * Pending breakpoint support (also included in GDB 6.1)
1068 Support has been added to allow you to specify breakpoints in shared
1069 libraries that have not yet been loaded. If a breakpoint location
1070 cannot be found, and the "breakpoint pending" option is set to auto,
1071 GDB queries you if you wish to make the breakpoint pending on a future
1072 shared-library load. If and when GDB resolves the breakpoint symbol,
1073 the pending breakpoint is removed as one or more regular breakpoints
1076 Pending breakpoints are very useful for GCJ Java debugging.
1078 * Fixed ISO-C build problems
1080 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1081 non ISO-C code that stopped them being built using a more strict ISO-C
1082 compiler (e.g., IBM's C compiler).
1084 * Fixed build problem on IRIX 5
1086 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1087 wasn't able to compile compile on an IRIX 5 system.
1089 * Added execute permission to gdb/gdbserver/configure
1091 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1092 permission. This bug would cause configure to fail on a number of
1093 systems (Solaris, IRIX). Ref: server/519.
1095 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1097 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1098 has been updated to use constant array sizes.
1100 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1102 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1103 its generated DWARF Call Frame Info. This encoding was causing GDB to
1104 panic, that panic has been fixed. Ref: gdb/1628.
1106 * Fixed a problem when examining parameters in shared library code.
1108 When examining parameters in optimized shared library code generated
1109 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1110 not available''. GDB now correctly displays the variable's value.
1112 *** Changes in GDB 6.1:
1114 * Removed --with-mmalloc
1116 Support for the mmalloc memory manager has been removed, as it
1117 conflicted with the internal gdb byte cache.
1119 * Changes in AMD64 configurations
1121 The AMD64 target now includes the %cs and %ss registers. As a result
1122 the AMD64 remote protocol has changed; this affects the floating-point
1123 and SSE registers. If you rely on those registers for your debugging,
1124 you should upgrade gdbserver on the remote side.
1126 * Revised SPARC target
1128 The SPARC target has been completely revised, incorporating the
1129 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1130 support for LynxOS and SunOS 4 has been dropped. Calling functions
1131 from within GDB on operating systems with a non-executable stack
1132 (Solaris, OpenBSD) now works.
1136 GDB has a new C++ demangler which does a better job on the mangled
1137 names generated by current versions of g++. It also runs faster, so
1138 with this and other changes gdb should now start faster on large C++
1141 * DWARF 2 Location Expressions
1143 GDB support for location expressions has been extended to support function
1144 arguments and frame bases. Older versions of GDB could crash when they
1147 * C++ nested types and namespaces
1149 GDB's support for nested types and namespaces in C++ has been
1150 improved, especially if you use the DWARF 2 debugging format. (This
1151 is the default for recent versions of GCC on most platforms.)
1152 Specifically, if you have a class "Inner" defined within a class or
1153 namespace "Outer", then GDB realizes that the class's name is
1154 "Outer::Inner", not simply "Inner". This should greatly reduce the
1155 frequency of complaints about not finding RTTI symbols. In addition,
1156 if you are stopped at inside of a function defined within a namespace,
1157 GDB modifies its name lookup accordingly.
1159 * New native configurations
1161 NetBSD/amd64 x86_64-*-netbsd*
1162 OpenBSD/amd64 x86_64-*-openbsd*
1163 OpenBSD/alpha alpha*-*-openbsd*
1164 OpenBSD/sparc sparc-*-openbsd*
1165 OpenBSD/sparc64 sparc64-*-openbsd*
1167 * New debugging protocols
1169 M32R with SDI protocol m32r-*-elf*
1171 * "set prompt-escape-char" command deleted.
1173 The command "set prompt-escape-char" has been deleted. This command,
1174 and its very obscure effet on GDB's prompt, was never documented,
1175 tested, nor mentioned in the NEWS file.
1177 * OBSOLETE configurations and files
1179 Configurations that have been declared obsolete in this release have
1180 been commented out. Unless there is activity to revive these
1181 configurations, the next release of GDB will have their sources
1182 permanently REMOVED.
1184 Sun 3, running SunOS 3 m68*-*-sunos3*
1185 Sun 3, running SunOS 4 m68*-*-sunos4*
1186 Sun 2, running SunOS 3 m68000-*-sunos3*
1187 Sun 2, running SunOS 4 m68000-*-sunos4*
1188 Motorola 680x0 running LynxOS m68*-*-lynxos*
1189 AT&T 3b1/Unix pc m68*-att-*
1190 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1191 decstation mips-dec-* mips-little-*
1192 riscos mips-*-riscos* mips-*-sysv*
1193 sonymips mips-sony-*
1194 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1196 * REMOVED configurations and files
1198 SGI Irix-4.x mips-sgi-irix4 or iris4
1199 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1200 Z8000 simulator z8k-zilog-none or z8ksim
1201 Matsushita MN10200 w/simulator mn10200-*-*
1202 H8/500 simulator h8500-hitachi-hms or h8500hms
1203 HP/PA running BSD hppa*-*-bsd*
1204 HP/PA running OSF/1 hppa*-*-osf*
1205 HP/PA Pro target hppa*-*-pro*
1206 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1207 386BSD i[3456]86-*-bsd*
1208 Sequent family i[3456]86-sequent-sysv4*
1209 i[3456]86-sequent-sysv*
1210 i[3456]86-sequent-bsd*
1211 SPARC running LynxOS sparc-*-lynxos*
1212 SPARC running SunOS 4 sparc-*-sunos4*
1213 Tsqware Sparclet sparclet-*-*
1214 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1216 *** Changes in GDB 6.0:
1220 Support for debugging the Objective-C programming language has been
1221 integrated into GDB.
1223 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1225 DWARF 2's Call Frame Information makes available compiler generated
1226 information that more exactly describes the program's run-time stack.
1227 By using this information, GDB is able to provide more robust stack
1230 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1231 have been updated to use a new backtrace mechanism which includes
1232 DWARF 2 CFI support.
1236 GDB's remote protocol has been extended to include support for hosted
1237 file I/O (where the remote target uses GDB's file system). See GDB's
1238 remote protocol documentation for details.
1240 * All targets using the new architecture framework.
1242 All of GDB's targets have been updated to use the new internal
1243 architecture framework. The way is now open for future GDB releases
1244 to include cross-architecture native debugging support (i386 on amd64,
1247 * GNU/Linux's Thread Local Storage (TLS)
1249 GDB now includes support for for the GNU/Linux implementation of
1250 per-thread variables.
1252 * GNU/Linux's Native POSIX Thread Library (NPTL)
1254 GDB's thread code has been updated to work with either the new
1255 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1257 * Separate debug info.
1259 GDB, in conjunction with BINUTILS, now supports a mechanism for
1260 automatically loading debug information from a separate file. Instead
1261 of shipping full debug and non-debug versions of system libraries,
1262 system integrators can now instead ship just the stripped libraries
1263 and optional debug files.
1265 * DWARF 2 Location Expressions
1267 DWARF 2 Location Expressions allow the compiler to more completely
1268 describe the location of variables (even in optimized code) to the
1271 GDB now includes preliminary support for location expressions (support
1272 for DW_OP_piece is still missing).
1276 A number of long standing bugs that caused GDB to die while starting a
1277 Java application have been fixed. GDB's Java support is now
1278 considered "useable".
1280 * GNU/Linux support for fork, vfork, and exec.
1282 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1283 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1286 * GDB supports logging output to a file
1288 There are two new commands, "set logging" and "show logging", which can be
1289 used to capture GDB's output to a file.
1291 * The meaning of "detach" has changed for gdbserver
1293 The "detach" command will now resume the application, as documented. To
1294 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1297 * d10v, m68hc11 `regs' command deprecated
1299 The `info registers' command has been updated so that it displays the
1300 registers using a format identical to the old `regs' command.
1304 A new command, "maint set profile on/off", has been added. This command can
1305 be used to enable or disable profiling while running GDB, to profile a
1306 session or a set of commands. In addition there is a new configure switch,
1307 "--enable-profiling", which will cause GDB to be compiled with profiling
1308 data, for more informative profiling results.
1310 * Default MI syntax changed to "mi2".
1312 The default MI (machine interface) syntax, enabled by the command line
1313 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1314 "mi1", can be enabled by specifying the option "-i=mi1".
1316 Support for the original "mi0" syntax (included in GDB 5.0) has been
1319 Fix for gdb/192: removed extraneous space when displaying frame level.
1320 Fix for gdb/672: update changelist is now output in mi list format.
1321 Fix for gdb/702: a -var-assign that updates the value now shows up
1322 in a subsequent -var-update.
1324 * New native configurations.
1326 FreeBSD/amd64 x86_64-*-freebsd*
1328 * Multi-arched targets.
1330 HP/PA HPUX11 hppa*-*-hpux*
1331 Renesas M32R/D w/simulator m32r-*-elf*
1333 * OBSOLETE configurations and files
1335 Configurations that have been declared obsolete in this release have
1336 been commented out. Unless there is activity to revive these
1337 configurations, the next release of GDB will have their sources
1338 permanently REMOVED.
1340 Z8000 simulator z8k-zilog-none or z8ksim
1341 Matsushita MN10200 w/simulator mn10200-*-*
1342 H8/500 simulator h8500-hitachi-hms or h8500hms
1343 HP/PA running BSD hppa*-*-bsd*
1344 HP/PA running OSF/1 hppa*-*-osf*
1345 HP/PA Pro target hppa*-*-pro*
1346 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1347 Sequent family i[3456]86-sequent-sysv4*
1348 i[3456]86-sequent-sysv*
1349 i[3456]86-sequent-bsd*
1350 Tsqware Sparclet sparclet-*-*
1351 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1353 * REMOVED configurations and files
1356 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1357 IBM AIX PS/2 i[3456]86-*-aix
1358 i386 running Mach 3.0 i[3456]86-*-mach3*
1359 i386 running Mach i[3456]86-*-mach*
1360 i386 running OSF/1 i[3456]86-*osf1mk*
1361 HP/Apollo 68k Family m68*-apollo*-sysv*,
1363 m68*-hp-bsd*, m68*-hp-hpux*
1364 Argonaut Risc Chip (ARC) arc-*-*
1365 Mitsubishi D30V d30v-*-*
1366 Fujitsu FR30 fr30-*-elf*
1367 OS/9000 i[34]86-*-os9k
1368 I960 with MON960 i960-*-coff
1370 * MIPS $fp behavior changed
1372 The convenience variable $fp, for the MIPS, now consistently returns
1373 the address of the current frame's base. Previously, depending on the
1374 context, $fp could refer to either $sp or the current frame's base
1375 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1376 The GNU Source-Level Debugger''.
1378 *** Changes in GDB 5.3:
1380 * GNU/Linux shared library multi-threaded performance improved.
1382 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1383 `/proc', in preference to `ptrace' for memory reads. This may result
1384 in an improvement in the start-up time of multi-threaded, shared
1385 library applications when run under GDB. One GDB user writes: ``loads
1386 shared libs like mad''.
1388 * ``gdbserver'' now supports multi-threaded applications on some targets
1390 Support for debugging multi-threaded applications which use
1391 the GNU/Linux LinuxThreads package has been added for
1392 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1393 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1395 * GDB now supports C/C++ preprocessor macros.
1397 GDB now expands preprocessor macro invocations in C/C++ expressions,
1398 and provides various commands for showing macro definitions and how
1401 The new command `macro expand EXPRESSION' expands any macro
1402 invocations in expression, and shows the result.
1404 The new command `show macro MACRO-NAME' shows the definition of the
1405 macro named MACRO-NAME, and where it was defined.
1407 Most compilers don't include information about macros in the debugging
1408 information by default. In GCC 3.1, for example, you need to compile
1409 your program with the options `-gdwarf-2 -g3'. If the macro
1410 information is present in the executable, GDB will read it.
1412 * Multi-arched targets.
1414 DEC Alpha (partial) alpha*-*-*
1415 DEC VAX (partial) vax-*-*
1417 National Semiconductor NS32000 (partial) ns32k-*-*
1418 Motorola 68000 (partial) m68k-*-*
1419 Motorola MCORE mcore-*-*
1423 Fujitsu FRV architecture added by Red Hat frv*-*-*
1426 * New native configurations
1428 Alpha NetBSD alpha*-*-netbsd*
1429 SH NetBSD sh*-*-netbsdelf*
1430 MIPS NetBSD mips*-*-netbsd*
1431 UltraSPARC NetBSD sparc64-*-netbsd*
1433 * OBSOLETE configurations and files
1435 Configurations that have been declared obsolete in this release have
1436 been commented out. Unless there is activity to revive these
1437 configurations, the next release of GDB will have their sources
1438 permanently REMOVED.
1440 Mitsubishi D30V d30v-*-*
1441 OS/9000 i[34]86-*-os9k
1442 IBM AIX PS/2 i[3456]86-*-aix
1443 Fujitsu FR30 fr30-*-elf*
1444 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1445 Argonaut Risc Chip (ARC) arc-*-*
1446 i386 running Mach 3.0 i[3456]86-*-mach3*
1447 i386 running Mach i[3456]86-*-mach*
1448 i386 running OSF/1 i[3456]86-*osf1mk*
1449 HP/Apollo 68k Family m68*-apollo*-sysv*,
1451 m68*-hp-bsd*, m68*-hp-hpux*
1452 I960 with MON960 i960-*-coff
1454 * OBSOLETE languages
1456 CHILL, a Pascal like language used by telecommunications companies.
1458 * REMOVED configurations and files
1460 AMD 29k family via UDI a29k-amd-udi, udi29k
1461 A29K VxWorks a29k-*-vxworks
1462 AMD 29000 embedded, using EBMON a29k-none-none
1463 AMD 29000 embedded with COFF a29k-none-coff
1464 AMD 29000 embedded with a.out a29k-none-aout
1466 testsuite/gdb.hp/gdb.threads-hp/ directory
1468 * New command "set max-user-call-depth <nnn>"
1470 This command allows the user to limit the call depth of user-defined
1471 commands. The default is 1024.
1473 * Changes in FreeBSD/i386 native debugging.
1475 Support for the "generate-core-file" has been added.
1477 * New commands "dump", "append", and "restore".
1479 These commands allow data to be copied from target memory
1480 to a bfd-format or binary file (dump and append), and back
1481 from a file into memory (restore).
1483 * Improved "next/step" support on multi-processor Alpha Tru64.
1485 The previous single-step mechanism could cause unpredictable problems,
1486 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1487 of a software single-step mechanism prevents this.
1489 *** Changes in GDB 5.2.1:
1497 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1498 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1499 Fix, by Joel Brobecker imported from mainline.
1501 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1502 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1503 Fix, by Fred Fish, imported from mainline.
1505 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1506 Surprisingly enough, it works now.
1507 By Michal Ludvig, imported from mainline.
1509 i386 hardware watchpoint support:
1510 avoid misses on second run for some targets.
1511 By Pierre Muller, imported from mainline.
1513 *** Changes in GDB 5.2:
1515 * New command "set trust-readonly-sections on[off]".
1517 This command is a hint that tells gdb that read-only sections
1518 really are read-only (ie. that their contents will not change).
1519 In this mode, gdb will go to the object file rather than the
1520 target to read memory from read-only sections (such as ".text").
1521 This can be a significant performance improvement on some
1522 (notably embedded) targets.
1524 * New command "generate-core-file" (or "gcore").
1526 This new gdb command allows the user to drop a core file of the child
1527 process state at any time. So far it's been implemented only for
1528 GNU/Linux and Solaris, but should be relatively easily ported to other
1529 hosts. Argument is core file name (defaults to core.<pid>).
1531 * New command line option
1533 GDB now accepts --pid or -p followed by a process id.
1535 * Change in command line behavior -- corefiles vs. process ids.
1537 There is a subtle behavior in the way in which GDB handles
1538 command line arguments. The first non-flag argument is always
1539 a program to debug, but the second non-flag argument may either
1540 be a corefile or a process id. Previously, GDB would attempt to
1541 open the second argument as a corefile, and if that failed, would
1542 issue a superfluous error message and then attempt to attach it as
1543 a process. Now, if the second argument begins with a non-digit,
1544 it will be treated as a corefile. If it begins with a digit,
1545 GDB will attempt to attach it as a process, and if no such process
1546 is found, will then attempt to open it as a corefile.
1548 * Changes in ARM configurations.
1550 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1551 configuration is fully multi-arch.
1553 * New native configurations
1555 ARM NetBSD arm*-*-netbsd*
1556 x86 OpenBSD i[3456]86-*-openbsd*
1557 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1558 Sparc64 running FreeBSD sparc64-*-freebsd*
1562 Sanyo XStormy16 xstormy16-elf
1564 * OBSOLETE configurations and files
1566 Configurations that have been declared obsolete in this release have
1567 been commented out. Unless there is activity to revive these
1568 configurations, the next release of GDB will have their sources
1569 permanently REMOVED.
1571 AMD 29k family via UDI a29k-amd-udi, udi29k
1572 A29K VxWorks a29k-*-vxworks
1573 AMD 29000 embedded, using EBMON a29k-none-none
1574 AMD 29000 embedded with COFF a29k-none-coff
1575 AMD 29000 embedded with a.out a29k-none-aout
1577 testsuite/gdb.hp/gdb.threads-hp/ directory
1579 * REMOVED configurations and files
1581 TI TMS320C80 tic80-*-*
1583 PowerPC Solaris powerpcle-*-solaris*
1584 PowerPC Windows NT powerpcle-*-cygwin32
1585 PowerPC Netware powerpc-*-netware*
1586 Harris/CXUX m88k m88*-harris-cxux*
1587 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1588 ns32k-utek-sysv* ns32k-utek-*
1589 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1590 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1591 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1592 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1593 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1595 * Changes to command line processing
1597 The new `--args' feature can be used to specify command-line arguments
1598 for the inferior from gdb's command line.
1600 * Changes to key bindings
1602 There is a new `operate-and-get-next' function bound to `C-o'.
1604 *** Changes in GDB 5.1.1
1606 Fix compile problem on DJGPP.
1608 Fix a problem with floating-point registers on the i386 being
1611 Fix to stop GDB crashing on .debug_str debug info.
1613 Numerous documentation fixes.
1615 Numerous testsuite fixes.
1617 *** Changes in GDB 5.1:
1619 * New native configurations
1621 Alpha FreeBSD alpha*-*-freebsd*
1622 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1623 MIPS GNU/Linux mips*-*-linux*
1624 MIPS SGI Irix 6.x mips*-sgi-irix6*
1625 ia64 AIX ia64-*-aix*
1626 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1630 Motorola 68HC11 and 68HC12 m68hc11-elf
1632 UltraSparc running GNU/Linux sparc64-*-linux*
1634 * OBSOLETE configurations and files
1636 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1637 Harris/CXUX m88k m88*-harris-cxux*
1638 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1639 ns32k-utek-sysv* ns32k-utek-*
1640 TI TMS320C80 tic80-*-*
1642 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1643 PowerPC Solaris powerpcle-*-solaris*
1644 PowerPC Windows NT powerpcle-*-cygwin32
1645 PowerPC Netware powerpc-*-netware*
1646 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1647 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1648 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1649 Apple Macintosh (MPW) host N/A
1651 stuff.c (Program to stuff files into a specially prepared space in kdb)
1652 kdb-start.c (Main loop for the standalone kernel debugger)
1654 Configurations that have been declared obsolete in this release have
1655 been commented out. Unless there is activity to revive these
1656 configurations, the next release of GDB will have their sources
1657 permanently REMOVED.
1659 * REMOVED configurations and files
1661 Altos 3068 m68*-altos-*
1662 Convex c1-*-*, c2-*-*
1664 ARM RISCix arm-*-* (as host)
1668 * GDB has been converted to ISO C.
1670 GDB's source code has been converted to ISO C. In particular, the
1671 sources are fully protoized, and rely on standard headers being
1676 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1678 * The MI enabled by default.
1680 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1681 revised and enabled by default. Packages which use GDB as a debugging
1682 engine behind a UI or another front end are encouraged to switch to
1683 using the GDB/MI interface, instead of the old annotations interface
1684 which is now deprecated.
1686 * Support for debugging Pascal programs.
1688 GDB now includes support for debugging Pascal programs. The following
1689 main features are supported:
1691 - Pascal-specific data types such as sets;
1693 - automatic recognition of Pascal sources based on file-name
1696 - Pascal-style display of data types, variables, and functions;
1698 - a Pascal expression parser.
1700 However, some important features are not yet supported.
1702 - Pascal string operations are not supported at all;
1704 - there are some problems with boolean types;
1706 - Pascal type hexadecimal constants are not supported
1707 because they conflict with the internal variables format;
1709 - support for Pascal objects and classes is not full yet;
1711 - unlike Pascal, GDB is case-sensitive for symbol names.
1713 * Changes in completion.
1715 Commands such as `shell', `run' and `set args', which pass arguments
1716 to inferior programs, now complete on file names, similar to what
1717 users expect at the shell prompt.
1719 Commands which accept locations, such as `disassemble', `print',
1720 `breakpoint', `until', etc. now complete on filenames as well as
1721 program symbols. Thus, if you type "break foob TAB", and the source
1722 files linked into the programs include `foobar.c', that file name will
1723 be one of the candidates for completion. However, file names are not
1724 considered for completion after you typed a colon that delimits a file
1725 name from a name of a function in that file, as in "break foo.c:bar".
1727 `set demangle-style' completes on available demangling styles.
1729 * New platform-independent commands:
1731 It is now possible to define a post-hook for a command as well as a
1732 hook that runs before the command. For more details, see the
1733 documentation of `hookpost' in the GDB manual.
1735 * Changes in GNU/Linux native debugging.
1737 Support for debugging multi-threaded programs has been completely
1738 revised for all platforms except m68k and sparc. You can now debug as
1739 many threads as your system allows you to have.
1741 Attach/detach is supported for multi-threaded programs.
1743 Support for SSE registers was added for x86. This doesn't work for
1744 multi-threaded programs though.
1746 * Changes in MIPS configurations.
1748 Multi-arch support is enabled for all MIPS configurations.
1750 GDB can now be built as native debugger on SGI Irix 6.x systems for
1751 debugging n32 executables. (Debugging 64-bit executables is not yet
1754 * Unified support for hardware watchpoints in all x86 configurations.
1756 Most (if not all) native x86 configurations support hardware-assisted
1757 breakpoints and watchpoints in a unified manner. This support
1758 implements debug register sharing between watchpoints, which allows to
1759 put a virtually infinite number of watchpoints on the same address,
1760 and also supports watching regions up to 16 bytes with several debug
1763 The new maintenance command `maintenance show-debug-regs' toggles
1764 debugging print-outs in functions that insert, remove, and test
1765 watchpoints and hardware breakpoints.
1767 * Changes in the DJGPP native configuration.
1769 New command ``info dos sysinfo'' displays assorted information about
1770 the CPU, OS, memory, and DPMI server.
1772 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1773 display information about segment descriptors stored in GDT, LDT, and
1776 New commands ``info dos pde'' and ``info dos pte'' display entries
1777 from Page Directory and Page Tables (for now works with CWSDPMI only).
1778 New command ``info dos address-pte'' displays the Page Table entry for
1779 a given linear address.
1781 GDB can now pass command lines longer than 126 characters to the
1782 program being debugged (requires an update to the libdbg.a library
1783 which is part of the DJGPP development kit).
1785 DWARF2 debug info is now supported.
1787 It is now possible to `step' and `next' through calls to `longjmp'.
1789 * Changes in documentation.
1791 All GDB documentation was converted to GFDL, the GNU Free
1792 Documentation License.
1794 Tracepoints-related commands are now fully documented in the GDB
1797 TUI, the Text-mode User Interface, is now documented in the manual.
1799 Tracepoints-related commands are now fully documented in the GDB
1802 The "GDB Internals" manual now has an index. It also includes
1803 documentation of `ui_out' functions, GDB coding standards, x86
1804 hardware watchpoints, and memory region attributes.
1806 * GDB's version number moved to ``version.in''
1808 The Makefile variable VERSION has been replaced by the file
1809 ``version.in''. People creating GDB distributions should update the
1810 contents of this file.
1814 GUD support is now a standard part of the EMACS distribution.
1816 *** Changes in GDB 5.0:
1818 * Improved support for debugging FP programs on x86 targets
1820 Unified and much-improved support for debugging floating-point
1821 programs on all x86 targets. In particular, ``info float'' now
1822 displays the FP registers in the same format on all x86 targets, with
1823 greater level of detail.
1825 * Improvements and bugfixes in hardware-assisted watchpoints
1827 It is now possible to watch array elements, struct members, and
1828 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1829 on x86 targets no longer erroneously trigger when the address is
1832 * Improvements in the native DJGPP version of GDB
1834 The distribution now includes all the scripts and auxiliary files
1835 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1836 machines ``out of the box''.
1838 The DJGPP version can now debug programs that use signals. It is
1839 possible to catch signals that happened in the debuggee, deliver
1840 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1841 would kill the program being debugged.) Programs that hook hardware
1842 interrupts (keyboard, timer, etc.) can also be debugged.
1844 It is now possible to debug DJGPP programs that redirect their
1845 standard handles or switch them to raw (as opposed to cooked) mode, or
1846 even close them. The command ``run < foo > bar'' works as expected,
1847 and ``info terminal'' reports useful information about the debuggee's
1848 terminal, including raw/cooked mode, redirection, etc.
1850 The DJGPP version now uses termios functions for console I/O, which
1851 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1854 DOS-style file names with drive letters are now fully supported by
1857 It is now possible to debug DJGPP programs that switch their working
1858 directory. It is also possible to rerun the debuggee any number of
1859 times without restarting GDB; thus, you can use the same setup,
1860 breakpoints, etc. for many debugging sessions.
1862 * New native configurations
1864 ARM GNU/Linux arm*-*-linux*
1865 PowerPC GNU/Linux powerpc-*-linux*
1869 Motorola MCore mcore-*-*
1870 x86 VxWorks i[3456]86-*-vxworks*
1871 PowerPC VxWorks powerpc-*-vxworks*
1872 TI TMS320C80 tic80-*-*
1874 * OBSOLETE configurations
1876 Altos 3068 m68*-altos-*
1877 Convex c1-*-*, c2-*-*
1879 ARM RISCix arm-*-* (as host)
1882 Configurations that have been declared obsolete will be commented out,
1883 but the code will be left in place. If there is no activity to revive
1884 these configurations before the next release of GDB, the sources will
1885 be permanently REMOVED.
1887 * Gould support removed
1889 Support for the Gould PowerNode and NP1 has been removed.
1891 * New features for SVR4
1893 On SVR4 native platforms (such as Solaris), if you attach to a process
1894 without first loading a symbol file, GDB will now attempt to locate and
1895 load symbols from the running process's executable file.
1897 * Many C++ enhancements
1899 C++ support has been greatly improved. Overload resolution now works properly
1900 in almost all cases. RTTI support is on the way.
1902 * Remote targets can connect to a sub-program
1904 A popen(3) style serial-device has been added. This device starts a
1905 sub-process (such as a stand-alone simulator) and then communicates
1906 with that. The sub-program to run is specified using the syntax
1907 ``|<program> <args>'' vis:
1909 (gdb) set remotedebug 1
1910 (gdb) target extended-remote |mn10300-elf-sim program-args
1912 * MIPS 64 remote protocol
1914 A long standing bug in the mips64 remote protocol where by GDB
1915 expected certain 32 bit registers (ex SR) to be transfered as 32
1916 instead of 64 bits has been fixed.
1918 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1919 added to provide backward compatibility with older versions of GDB.
1921 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1923 The command ``set remotebinarydownload'' command has been replaced by
1924 ``set remote X-packet''. Other commands in ``set remote'' family
1925 include ``set remote P-packet''.
1927 * Breakpoint commands accept ranges.
1929 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1930 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1931 ``tracepoint passcount'' also accepts a range of tracepoints.
1933 * ``apropos'' command added.
1935 The ``apropos'' command searches through command names and
1936 documentation strings, printing out matches, making it much easier to
1937 try to find a command that does what you are looking for.
1941 A new machine oriented interface (MI) has been added to GDB. This
1942 interface is designed for debug environments running GDB as a separate
1943 process. This is part of the long term libGDB project. See the
1944 "GDB/MI" chapter of the GDB manual for further information. It can be
1945 enabled by configuring with:
1947 .../configure --enable-gdbmi
1949 *** Changes in GDB-4.18:
1951 * New native configurations
1953 HP-UX 10.20 hppa*-*-hpux10.20
1954 HP-UX 11.x hppa*-*-hpux11.0*
1955 M68K GNU/Linux m68*-*-linux*
1959 Fujitsu FR30 fr30-*-elf*
1960 Intel StrongARM strongarm-*-*
1961 Mitsubishi D30V d30v-*-*
1963 * OBSOLETE configurations
1965 Gould PowerNode, NP1 np1-*-*, pn-*-*
1967 Configurations that have been declared obsolete will be commented out,
1968 but the code will be left in place. If there is no activity to revive
1969 these configurations before the next release of GDB, the sources will
1970 be permanently REMOVED.
1974 As a compatibility experiment, GDB's source files buildsym.h and
1975 buildsym.c have been converted to pure standard C, no longer
1976 containing any K&R compatibility code. We believe that all systems in
1977 use today either come with a standard C compiler, or have a GCC port
1978 available. If this is not true, please report the affected
1979 configuration to bug-gdb@gnu.org immediately. See the README file for
1980 information about getting a standard C compiler if you don't have one
1985 GDB now uses readline 2.2.
1987 * set extension-language
1989 You can now control the mapping between filename extensions and source
1990 languages by using the `set extension-language' command. For instance,
1991 you can ask GDB to treat .c files as C++ by saying
1992 set extension-language .c c++
1993 The command `info extensions' lists all of the recognized extensions
1994 and their associated languages.
1996 * Setting processor type for PowerPC and RS/6000
1998 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1999 you can use the `set processor' command to specify what variant of the
2000 PowerPC family you are debugging. The command
2004 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2005 following PowerPC and RS6000 variants:
2007 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2008 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2010 403GC IBM PowerPC 403GC
2011 505 Motorola PowerPC 505
2012 860 Motorola PowerPC 860 or 850
2013 601 Motorola PowerPC 601
2014 602 Motorola PowerPC 602
2015 603 Motorola/IBM PowerPC 603 or 603e
2016 604 Motorola PowerPC 604 or 604e
2017 750 Motorola/IBM PowerPC 750 or 750
2019 At the moment, this command just tells GDB what to name the
2020 special-purpose processor registers. Since almost all the affected
2021 registers are inaccessible to user-level programs, this command is
2022 only useful for remote debugging in its present form.
2026 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2027 more extensive support for HP-UX. Added features include shared
2028 library support, kernel threads and hardware watchpoints for 11.00,
2029 support for HP's ANSI C and C++ compilers, and a compatibility mode
2030 for xdb and dbx commands.
2034 HP's donation includes the new concept of catchpoints, which is a
2035 generalization of the old catch command. On HP-UX, it is now possible
2036 to catch exec, fork, and vfork, as well as library loading.
2038 This means that the existing catch command has changed; its first
2039 argument now specifies the type of catch to be set up. See the
2040 output of "help catch" for a list of catchpoint types.
2042 * Debugging across forks
2044 On HP-UX, you can choose which process to debug when a fork() happens
2049 HP has donated a curses-based terminal user interface (TUI). To get
2050 it, build with --enable-tui. Although this can be enabled for any
2051 configuration, at present it only works for native HP debugging.
2053 * GDB remote protocol additions
2055 A new protocol packet 'X' that writes binary data is now available.
2056 Default behavior is to try 'X', then drop back to 'M' if the stub
2057 fails to respond. The settable variable `remotebinarydownload'
2058 allows explicit control over the use of 'X'.
2060 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2061 full 64-bit address. The command
2063 set remoteaddresssize 32
2065 can be used to revert to the old behaviour. For existing remote stubs
2066 the change should not be noticed, as the additional address information
2069 In order to assist in debugging stubs, you may use the maintenance
2070 command `packet' to send any text string to the stub. For instance,
2072 maint packet heythere
2074 sends the packet "$heythere#<checksum>". Note that it is very easy to
2075 disrupt a debugging session by sending the wrong packet at the wrong
2078 The compare-sections command allows you to compare section data on the
2079 target to what is in the executable file without uploading or
2080 downloading, by comparing CRC checksums.
2082 * Tracing can collect general expressions
2084 You may now collect general expressions at tracepoints. This requires
2085 further additions to the target-side stub; see tracepoint.c and
2086 doc/agentexpr.texi for further details.
2088 * mask-address variable for Mips
2090 For Mips targets, you may control the zeroing of the upper 32 bits of
2091 a 64-bit address by entering `set mask-address on'. This is mainly
2092 of interest to users of embedded R4xxx and R5xxx processors.
2094 * Higher serial baud rates
2096 GDB's serial code now allows you to specify baud rates 57600, 115200,
2097 230400, and 460800 baud. (Note that your host system may not be able
2098 to achieve all of these rates.)
2102 The i960 configuration now includes an initial implementation of a
2103 builtin simulator, contributed by Jim Wilson.
2106 *** Changes in GDB-4.17:
2108 * New native configurations
2110 Alpha GNU/Linux alpha*-*-linux*
2111 Unixware 2.x i[3456]86-unixware2*
2112 Irix 6.x mips*-sgi-irix6*
2113 PowerPC GNU/Linux powerpc-*-linux*
2114 PowerPC Solaris powerpcle-*-solaris*
2115 Sparc GNU/Linux sparc-*-linux*
2116 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2120 Argonaut Risc Chip (ARC) arc-*-*
2121 Hitachi H8/300S h8300*-*-*
2122 Matsushita MN10200 w/simulator mn10200-*-*
2123 Matsushita MN10300 w/simulator mn10300-*-*
2124 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2125 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2126 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2127 Mitsubishi D10V w/simulator d10v-*-*
2128 Mitsubishi M32R/D w/simulator m32r-*-elf*
2129 Tsqware Sparclet sparclet-*-*
2130 NEC V850 w/simulator v850-*-*
2132 * New debugging protocols
2134 ARM with RDI protocol arm*-*-*
2135 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2136 DDB and LSI variants of PMON protocol mips*-*-*
2137 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2138 PowerPC with SDS protocol powerpc{,le}-*-eabi
2139 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2143 All configurations can now understand and use the DWARF 2 debugging
2144 format. The choice is automatic, if the symbol file contains DWARF 2
2149 GDB now includes basic Java language support. This support is
2150 only useful with Java compilers that produce native machine code.
2152 * solib-absolute-prefix and solib-search-path
2154 For SunOS and SVR4 shared libraries, you may now set the prefix for
2155 loading absolute shared library symbol files, and the search path for
2156 locating non-absolute shared library symbol files.
2158 * Live range splitting
2160 GDB can now effectively debug code for which GCC has performed live
2161 range splitting as part of its optimization. See gdb/doc/LRS for
2162 more details on the expected format of the stabs information.
2166 GDB's support for the GNU Hurd, including thread debugging, has been
2167 updated to work with current versions of the Hurd.
2171 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2172 instruction set. ARM GDB automatically detects when Thumb
2173 instructions are in use, and adjusts disassembly and backtracing
2178 GDB's MIPS target configurations now handle the MIP16 16-bit
2183 GDB now includes support for overlays; if an executable has been
2184 linked such that multiple sections are based at the same address, GDB
2185 will decide which section to use for symbolic info. You can choose to
2186 control the decision manually, using overlay commands, or implement
2187 additional target-side support and use "overlay load-target" to bring
2188 in the overlay mapping. Do "help overlay" for more detail.
2192 The command "info symbol <address>" displays information about
2193 the symbol at the specified address.
2197 The standard remote protocol now includes an extension that allows
2198 asynchronous collection and display of trace data. This requires
2199 extensive support in the target-side debugging stub. Tracing mode
2200 includes a new interaction mode in GDB and new commands: see the
2201 file tracepoint.c for more details.
2205 Configurations for embedded MIPS now include a simulator contributed
2206 by Cygnus Solutions. The simulator supports the instruction sets
2207 of most MIPS variants.
2211 Sparc configurations may now include the ERC32 simulator contributed
2212 by the European Space Agency. The simulator is not built into
2213 Sparc targets by default; configure with --enable-sim to include it.
2217 For target configurations that may include multiple variants of a
2218 basic architecture (such as MIPS and SH), you may now set the
2219 architecture explicitly. "set arch" sets, "info arch" lists
2220 the possible architectures.
2222 *** Changes in GDB-4.16:
2224 * New native configurations
2226 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2227 M68K NetBSD m68k-*-netbsd*
2228 PowerPC AIX 4.x powerpc-*-aix*
2229 PowerPC MacOS powerpc-*-macos*
2230 PowerPC Windows NT powerpcle-*-cygwin32
2231 RS/6000 AIX 4.x rs6000-*-aix4*
2235 ARM with RDP protocol arm-*-*
2236 I960 with MON960 i960-*-coff
2237 MIPS VxWorks mips*-*-vxworks*
2238 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2239 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2241 Matra Sparclet sparclet-*-*
2245 The powerpc-eabi configuration now includes the PSIM simulator,
2246 contributed by Andrew Cagney, with assistance from Mike Meissner.
2247 PSIM is a very elaborate model of the PowerPC, including not only
2248 basic instruction set execution, but also details of execution unit
2249 performance and I/O hardware. See sim/ppc/README for more details.
2253 GDB now works with Solaris 2.5.
2255 * Windows 95/NT native
2257 GDB will now work as a native debugger on Windows 95 and Windows NT.
2258 To build it from source, you must use the "gnu-win32" environment,
2259 which uses a DLL to emulate enough of Unix to run the GNU tools.
2260 Further information, binaries, and sources are available at
2261 ftp.cygnus.com, under pub/gnu-win32.
2263 * dont-repeat command
2265 If a user-defined command includes the command `dont-repeat', then the
2266 command will not be repeated if the user just types return. This is
2267 useful if the command is time-consuming to run, so that accidental
2268 extra keystrokes don't run the same command many times.
2270 * Send break instead of ^C
2272 The standard remote protocol now includes an option to send a break
2273 rather than a ^C to the target in order to interrupt it. By default,
2274 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2276 * Remote protocol timeout
2278 The standard remote protocol includes a new variable `remotetimeout'
2279 that allows you to set the number of seconds before GDB gives up trying
2280 to read from the target. The default value is 2.
2282 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2284 By default GDB will automatically keep track of objects as they are
2285 loaded and unloaded by the dynamic linker. By using the command `set
2286 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2287 when shared library events occur, thus allowing you to set breakpoints
2288 in shared libraries which are explicitly loaded by the inferior.
2290 Note this feature does not work on hpux8. On hpux9 you must link
2291 /usr/lib/end.o into your program. This feature should work
2292 automatically on hpux10.
2294 * Irix 5.x hardware watchpoint support
2296 Irix 5 configurations now support the use of hardware watchpoints.
2298 * Mips protocol "SYN garbage limit"
2300 When debugging a Mips target using the `target mips' protocol, you
2301 may set the number of characters that GDB will ignore by setting
2302 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2303 every character. The default value is 1050.
2305 * Recording and replaying remote debug sessions
2307 If you set `remotelogfile' to the name of a file, gdb will write to it
2308 a recording of a remote debug session. This recording may then be
2309 replayed back to gdb using "gdbreplay". See gdbserver/README for
2310 details. This is useful when you have a problem with GDB while doing
2311 remote debugging; you can make a recording of the session and send it
2312 to someone else, who can then recreate the problem.
2314 * Speedups for remote debugging
2316 GDB includes speedups for downloading and stepping MIPS systems using
2317 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2318 and more efficient S-record downloading.
2320 * Memory use reductions and statistics collection
2322 GDB now uses less memory and reports statistics about memory usage.
2323 Try the `maint print statistics' command, for example.
2325 *** Changes in GDB-4.15:
2327 * Psymtabs for XCOFF
2329 The symbol reader for AIX GDB now uses partial symbol tables. This
2330 can greatly improve startup time, especially for large executables.
2332 * Remote targets use caching
2334 Remote targets now use a data cache to speed up communication with the
2335 remote side. The data cache could lead to incorrect results because
2336 it doesn't know about volatile variables, thus making it impossible to
2337 debug targets which use memory mapped I/O devices. `set remotecache
2338 off' turns the the data cache off.
2340 * Remote targets may have threads
2342 The standard remote protocol now includes support for multiple threads
2343 in the target system, using new protocol commands 'H' and 'T'. See
2344 gdb/remote.c for details.
2348 If GDB is configured with `--enable-netrom', then it will include
2349 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2350 acts as though it is a bank of ROM on the target board, but you can
2351 write into it over the network. GDB's support consists only of
2352 support for fast loading into the emulated ROM; to debug, you must use
2353 another protocol, such as standard remote protocol. The usual
2354 sequence is something like
2356 target nrom <netrom-hostname>
2358 target remote <netrom-hostname>:1235
2362 GDB now includes support for the Apple Macintosh, as a host only. It
2363 may be run as either an MPW tool or as a standalone application, and
2364 it can debug through the serial port. All the usual GDB commands are
2365 available, but to the target command, you must supply "serial" as the
2366 device type instead of "/dev/ttyXX". See mpw-README in the main
2367 directory for more information on how to build. The MPW configuration
2368 scripts */mpw-config.in support only a few targets, and only the
2369 mips-idt-ecoff target has been tested.
2373 GDB configuration now uses autoconf. This is not user-visible,
2374 but does simplify configuration and building.
2378 GDB now supports hpux10.
2380 *** Changes in GDB-4.14:
2382 * New native configurations
2384 x86 FreeBSD i[345]86-*-freebsd
2385 x86 NetBSD i[345]86-*-netbsd
2386 NS32k NetBSD ns32k-*-netbsd
2387 Sparc NetBSD sparc-*-netbsd
2391 A29K VxWorks a29k-*-vxworks
2392 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2393 CPU32 EST-300 emulator m68*-*-est*
2394 PowerPC ELF powerpc-*-elf
2397 * Alpha OSF/1 support for procfs
2399 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2400 possible to attach to running processes. As the mounting of the /proc
2401 filesystem is optional on the Alpha, GDB automatically determines
2402 the availability of /proc during startup. This can lead to problems
2403 if /proc is unmounted after GDB has been started.
2405 * Arguments to user-defined commands
2407 User commands may accept up to 10 arguments separated by whitespace.
2408 Arguments are accessed within the user command via $arg0..$arg9. A
2411 print $arg0 + $arg1 + $arg2
2413 To execute the command use:
2416 Defines the command "adder" which prints the sum of its three arguments.
2417 Note the arguments are text substitutions, so they may reference variables,
2418 use complex expressions, or even perform inferior function calls.
2420 * New `if' and `while' commands
2422 This makes it possible to write more sophisticated user-defined
2423 commands. Both commands take a single argument, which is the
2424 expression to evaluate, and must be followed by the commands to
2425 execute, one per line, if the expression is nonzero, the list being
2426 terminated by the word `end'. The `if' command list may include an
2427 `else' word, which causes the following commands to be executed only
2428 if the expression is zero.
2430 * Fortran source language mode
2432 GDB now includes partial support for Fortran 77. It will recognize
2433 Fortran programs and can evaluate a subset of Fortran expressions, but
2434 variables and functions may not be handled correctly. GDB will work
2435 with G77, but does not yet know much about symbols emitted by other
2438 * Better HPUX support
2440 Most debugging facilities now work on dynamic executables for HPPAs
2441 running hpux9 or later. You can attach to running dynamically linked
2442 processes, but by default the dynamic libraries will be read-only, so
2443 for instance you won't be able to put breakpoints in them. To change
2444 that behavior do the following before running the program:
2450 This will cause the libraries to be mapped private and read-write.
2451 To revert to the normal behavior, do this:
2457 You cannot set breakpoints or examine data in the library until after
2458 the library is loaded if the function/data symbols do not have
2461 GDB can now also read debug symbols produced by the HP C compiler on
2462 HPPAs (sorry, no C++, Fortran or 68k support).
2464 * Target byte order now dynamically selectable
2466 You can choose which byte order to use with a target system, via the
2467 commands "set endian big" and "set endian little", and you can see the
2468 current setting by using "show endian". You can also give the command
2469 "set endian auto", in which case GDB will use the byte order
2470 associated with the executable. Currently, only embedded MIPS
2471 configurations support dynamic selection of target byte order.
2473 * New DOS host serial code
2475 This version uses DPMI interrupts to handle buffered I/O, so you
2476 no longer need to run asynctsr when debugging boards connected to
2479 *** Changes in GDB-4.13:
2481 * New "complete" command
2483 This lists all the possible completions for the rest of the line, if it
2484 were to be given as a command itself. This is intended for use by emacs.
2486 * Trailing space optional in prompt
2488 "set prompt" no longer adds a space for you after the prompt you set. This
2489 allows you to set a prompt which ends in a space or one that does not.
2491 * Breakpoint hit counts
2493 "info break" now displays a count of the number of times the breakpoint
2494 has been hit. This is especially useful in conjunction with "ignore"; you
2495 can ignore a large number of breakpoint hits, look at the breakpoint info
2496 to see how many times the breakpoint was hit, then run again, ignoring one
2497 less than that number, and this will get you quickly to the last hit of
2500 * Ability to stop printing at NULL character
2502 "set print null-stop" will cause GDB to stop printing the characters of
2503 an array when the first NULL is encountered. This is useful when large
2504 arrays actually contain only short strings.
2506 * Shared library breakpoints
2508 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2509 breakpoints in shared libraries before the executable is run.
2511 * Hardware watchpoints
2513 There is a new hardware breakpoint for the watch command for sparclite
2514 targets. See gdb/sparclite/hw_breakpoint.note.
2516 Hardware watchpoints are also now supported under GNU/Linux.
2520 Annotations have been added. These are for use with graphical interfaces,
2521 and are still experimental. Currently only gdba.el uses these.
2523 * Improved Irix 5 support
2525 GDB now works properly with Irix 5.2.
2527 * Improved HPPA support
2529 GDB now works properly with the latest GCC and GAS.
2531 * New native configurations
2533 Sequent PTX4 i[34]86-sequent-ptx4
2534 HPPA running OSF/1 hppa*-*-osf*
2535 Atari TT running SVR4 m68*-*-sysv4*
2536 RS/6000 LynxOS rs6000-*-lynxos*
2540 OS/9000 i[34]86-*-os9k
2541 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2544 * Hitachi SH7000 and E7000-PC ICE support
2546 There is now support for communicating with the Hitachi E7000-PC ICE.
2547 This is available automatically when GDB is configured for the SH.
2551 As usual, a variety of small fixes and improvements, both generic
2552 and configuration-specific. See the ChangeLog for more detail.
2554 *** Changes in GDB-4.12:
2556 * Irix 5 is now supported
2560 GDB-4.12 on the HPPA has a number of changes which make it unable
2561 to debug the output from the currently released versions of GCC and
2562 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2563 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2564 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2567 *** Changes in GDB-4.11:
2569 * User visible changes:
2573 The "set remotedebug" option is now consistent between the mips remote
2574 target, remote targets using the gdb-specific protocol, UDI (AMD's
2575 debug protocol for the 29k) and the 88k bug monitor. It is now an
2576 integer specifying a debug level (normally 0 or 1, but 2 means more
2577 debugging info for the mips target).
2579 * DEC Alpha native support
2581 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2582 debug info, but GDB works fairly well with the DEC compiler and should
2583 work with a future GCC release. See the README file for a few
2584 Alpha-specific notes.
2586 * Preliminary thread implementation
2588 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2590 * LynxOS native and target support for 386
2592 This release has been hosted on LynxOS 2.2, and also can be configured
2593 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2596 * Improvements in C++ mangling/demangling.
2598 This release has much better g++ debugging, specifically in name
2599 mangling/demangling, virtual function calls, print virtual table,
2600 call methods, ...etc.
2602 *** Changes in GDB-4.10:
2604 * User visible changes:
2606 Remote debugging using the GDB-specific (`target remote') protocol now
2607 supports the `load' command. This is only useful if you have some
2608 other way of getting the stub to the target system, and you can put it
2609 somewhere in memory where it won't get clobbered by the download.
2611 Filename completion now works.
2613 When run under emacs mode, the "info line" command now causes the
2614 arrow to point to the line specified. Also, "info line" prints
2615 addresses in symbolic form (as well as hex).
2617 All vxworks based targets now support a user settable option, called
2618 vxworks-timeout. This option represents the number of seconds gdb
2619 should wait for responses to rpc's. You might want to use this if
2620 your vxworks target is, perhaps, a slow software simulator or happens
2621 to be on the far side of a thin network line.
2625 This release contains support for using a DEC alpha as a GDB host for
2626 cross debugging. Native alpha debugging is not supported yet.
2629 *** Changes in GDB-4.9:
2633 This is the first GDB release which is accompanied by a matching testsuite.
2634 The testsuite requires installation of dejagnu, which should be available
2635 via ftp from most sites that carry GNU software.
2639 'Cfront' style demangling has had its name changed to 'ARM' style, to
2640 emphasize that it was written from the specifications in the C++ Annotated
2641 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2642 disclaimers, it still generated too much confusion with users attempting to
2643 use gdb with AT&T cfront.
2647 GDB now uses a standard remote interface to a simulator library.
2648 So far, the library contains simulators for the Zilog Z8001/2, the
2649 Hitachi H8/300, H8/500 and Super-H.
2651 * New targets supported
2653 H8/300 simulator h8300-hitachi-hms or h8300hms
2654 H8/500 simulator h8500-hitachi-hms or h8500hms
2655 SH simulator sh-hitachi-hms or sh
2656 Z8000 simulator z8k-zilog-none or z8ksim
2657 IDT MIPS board over serial line mips-idt-ecoff
2659 Cross-debugging to GO32 targets is supported. It requires a custom
2660 version of the i386-stub.c module which is integrated with the
2661 GO32 memory extender.
2663 * New remote protocols
2665 MIPS remote debugging protocol.
2667 * New source languages supported
2669 This version includes preliminary support for Chill, a Pascal like language
2670 used by telecommunications companies. Chill support is also being integrated
2671 into the GNU compiler, but we don't know when it will be publically available.
2674 *** Changes in GDB-4.8:
2676 * HP Precision Architecture supported
2678 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2679 version of this support was available as a set of patches from the
2680 University of Utah. GDB does not support debugging of programs
2681 compiled with the HP compiler, because HP will not document their file
2682 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2683 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2685 Many problems in the preliminary version have been fixed.
2687 * Faster and better demangling
2689 We have improved template demangling and fixed numerous bugs in the GNU style
2690 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2691 character types (wchar_t) are now supported. Demangling of each symbol is now
2692 only done once, and is cached when the symbol table for a file is read in.
2693 This results in a small increase in memory usage for C programs, a moderate
2694 increase in memory usage for C++ programs, and a fantastic speedup in
2697 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2698 from the specifications in the Annotated Reference Manual, which AT&T's
2699 compiler does not actually implement.
2701 * G++ multiple inheritance compiler problem
2703 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2704 inheritance lattices was reworked to properly discover ambiguities. We
2705 recently found an example which causes this new algorithm to fail in a
2706 very subtle way, producing bad debug information for those classes.
2707 The file 'gcc.patch' (in this directory) can be applied to gcc to
2708 circumvent the problem. A future GCC release will contain a complete
2711 The previous G++ debug info problem (mentioned below for the gdb-4.7
2712 release) is fixed in gcc version 2.3.2.
2714 * Improved configure script
2716 The `configure' script will now attempt to guess your system type if
2717 you don't supply a host system type. The old scheme of supplying a
2718 host system triplet is preferable over using this. All the magic is
2719 done in the new `config.guess' script. Examine it for details.
2721 We have also brought our configure script much more in line with the FSF's
2722 version. It now supports the --with-xxx options. In particular,
2723 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2724 The resulting GDB will not be able to read arbitrary object file formats --
2725 only the format ``expected'' to be used on the configured target system.
2726 We hope to make this the default in a future release.
2728 * Documentation improvements
2730 There's new internal documentation on how to modify GDB, and how to
2731 produce clean changes to the code. We implore people to read it
2732 before submitting changes.
2734 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2735 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2736 `info' files are also provided. To build `info' files from scratch,
2737 you will need the latest `makeinfo' release, which will be available in
2738 a future texinfo-X.Y release.
2740 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2741 We're not sure exactly which versions have this problem, but it has
2742 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2743 or better. If that isn't possible, there is a patch in
2744 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2745 around this problem.
2749 GDB now supports array constants that can be used in expressions typed in by
2750 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2751 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2754 The new directory `gdb/sparclite' contains a program that demonstrates
2755 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2757 * New native hosts supported
2759 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2760 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2762 * New targets supported
2764 AMD 29k family via UDI a29k-amd-udi or udi29k
2766 * New file formats supported
2768 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2769 HPUX core files, and SCO 3.2v2 core files.
2773 Attaching to processes now works again; thanks for the many bug reports.
2775 We have also stomped on a bunch of core dumps caused by
2776 printf_filtered("%s") problems.
2778 We eliminated a copyright problem on the rpc and ptrace header files
2779 for VxWorks, which was discovered at the last minute during the 4.7
2780 release. You should now be able to build a VxWorks GDB.
2782 You can now interrupt gdb while an attached process is running. This
2783 will cause the attached process to stop, and give control back to GDB.
2785 We fixed problems caused by using too many file descriptors
2786 for reading symbols from object files and libraries. This was
2787 especially a problem for programs that used many (~100) shared
2790 The `step' command now only enters a subroutine if there is line number
2791 information for the subroutine. Otherwise it acts like the `next'
2792 command. Previously, `step' would enter subroutines if there was
2793 any debugging information about the routine. This avoids problems
2794 when using `cc -g1' on MIPS machines.
2796 * Internal improvements
2798 GDB's internal interfaces have been improved to make it easier to support
2799 debugging of multiple languages in the future.
2801 GDB now uses a common structure for symbol information internally.
2802 Minimal symbols (derived from linkage symbols in object files), partial
2803 symbols (from a quick scan of debug information), and full symbols
2804 contain a common subset of information, making it easier to write
2805 shared code that handles any of them.
2807 * New command line options
2809 We now accept --silent as an alias for --quiet.
2813 The memory-mapped-malloc library is now licensed under the GNU Library
2814 General Public License.
2816 *** Changes in GDB-4.7:
2818 * Host/native/target split
2820 GDB has had some major internal surgery to untangle the support for
2821 hosts and remote targets. Now, when you configure GDB for a remote
2822 target, it will no longer load in all of the support for debugging
2823 local programs on the host. When fully completed and tested, this will
2824 ensure that arbitrary host/target combinations are possible.
2826 The primary conceptual shift is to separate the non-portable code in
2827 GDB into three categories. Host specific code is required any time GDB
2828 is compiled on that host, regardless of the target. Target specific
2829 code relates to the peculiarities of the target, but can be compiled on
2830 any host. Native specific code is everything else: it can only be
2831 built when the host and target are the same system. Child process
2832 handling and core file support are two common `native' examples.
2834 GDB's use of /proc for controlling Unix child processes is now cleaner.
2835 It has been split out into a single module under the `target_ops' vector,
2836 plus two native-dependent functions for each system that uses /proc.
2838 * New hosts supported
2840 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2841 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2842 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2844 * New targets supported
2846 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2847 68030 and CPU32 m68030-*-*, m68332-*-*
2849 * New native hosts supported
2851 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2852 (386bsd is not well tested yet)
2853 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2855 * New file formats supported
2857 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2858 supports reading of `a.out.adobe' object files, which are an a.out
2859 format extended with minimal information about multiple sections.
2863 `show copying' is the same as the old `info copying'.
2864 `show warranty' is the same as `info warrantee'.
2865 These were renamed for consistency. The old commands continue to work.
2867 `info handle' is a new alias for `info signals'.
2869 You can now define pre-command hooks, which attach arbitrary command
2870 scripts to any command. The commands in the hook will be executed
2871 prior to the user's command. You can also create a hook which will be
2872 executed whenever the program stops. See gdb.texinfo.
2876 We now deal with Cfront style name mangling, and can even extract type
2877 info from mangled symbols. GDB can automatically figure out which
2878 symbol mangling style your C++ compiler uses.
2880 Calling of methods and virtual functions has been improved as well.
2884 The crash that occured when debugging Sun Ansi-C compiled binaries is
2885 fixed. This was due to mishandling of the extra N_SO stabs output
2888 We also finally got Ultrix 4.2 running in house, and fixed core file
2889 support, with help from a dozen people on the net.
2891 John M. Farrell discovered that the reason that single-stepping was so
2892 slow on all of the Mips based platforms (primarily SGI and DEC) was
2893 that we were trying to demangle and lookup a symbol used for internal
2894 purposes on every instruction that was being stepped through. Changing
2895 the name of that symbol so that it couldn't be mistaken for a C++
2896 mangled symbol sped things up a great deal.
2898 Rich Pixley sped up symbol lookups in general by getting much smarter
2899 about when C++ symbol mangling is necessary. This should make symbol
2900 completion (TAB on the command line) much faster. It's not as fast as
2901 we'd like, but it's significantly faster than gdb-4.6.
2905 A new user controllable variable 'call_scratch_address' can
2906 specify the location of a scratch area to be used when GDB
2907 calls a function in the target. This is necessary because the
2908 usual method of putting the scratch area on the stack does not work
2909 in systems that have separate instruction and data spaces.
2911 We integrated changes to support the 29k UDI (Universal Debugger
2912 Interface), but discovered at the last minute that we didn't have all
2913 of the appropriate copyright paperwork. We are working with AMD to
2914 resolve this, and hope to have it available soon.
2918 We have sped up the remote serial line protocol, especially for targets
2919 with lots of registers. It now supports a new `expedited status' ('T')
2920 message which can be used in place of the existing 'S' status message.
2921 This allows the remote stub to send only the registers that GDB
2922 needs to make a quick decision about single-stepping or conditional
2923 breakpoints, eliminating the need to fetch the entire register set for
2924 each instruction being stepped through.
2926 The GDB remote serial protocol now implements a write-through cache for
2927 registers, only re-reading the registers if the target has run.
2929 There is also a new remote serial stub for SPARC processors. You can
2930 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2931 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2932 processor with a serial port.
2936 Configure.in files have become much easier to read and modify. A new
2937 `table driven' format makes it more obvious what configurations are
2938 supported, and what files each one uses.
2942 There is a new opcodes library which will eventually contain all of the
2943 disassembly routines and opcode tables. At present, it only contains
2944 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2945 disassembler (binutils/objdump) to share these routines.
2947 The libiberty library is now copylefted under the GNU Library General
2948 Public License. This allows more liberal use, and was done so libg++
2949 can use it. This makes no difference to GDB, since the Library License
2950 grants all the rights from the General Public License.
2954 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2955 reference to the stabs symbol info used by the debugger. It is (as far
2956 as we know) the only published document on this fascinating topic. We
2957 encourage you to read it, compare it to the stabs information on your
2958 system, and send improvements on the document in general (to
2959 bug-gdb@prep.ai.mit.edu).
2961 And, of course, many bugs have been fixed.
2964 *** Changes in GDB-4.6:
2966 * Better support for C++ function names
2968 GDB now accepts as input the "demangled form" of C++ overloaded function
2969 names and member function names, and can do command completion on such names
2970 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2971 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2972 Make use of command completion, it is your friend.
2974 GDB also now accepts a variety of C++ mangled symbol formats. They are
2975 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2976 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2977 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2978 for the list of formats.
2980 * G++ symbol mangling problem
2982 Recent versions of gcc have a bug in how they emit debugging information for
2983 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2984 directory) can be applied to gcc to fix the problem. Alternatively, if you
2985 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2986 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2987 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2990 * New 'maintenance' command
2992 All of the commands related to hacking GDB internals have been moved out of
2993 the main command set, and now live behind the 'maintenance' command. This
2994 can also be abbreviated as 'mt'. The following changes were made:
2996 dump-me -> maintenance dump-me
2997 info all-breakpoints -> maintenance info breakpoints
2998 printmsyms -> maintenance print msyms
2999 printobjfiles -> maintenance print objfiles
3000 printpsyms -> maintenance print psymbols
3001 printsyms -> maintenance print symbols
3003 The following commands are new:
3005 maintenance demangle Call internal GDB demangler routine to
3006 demangle a C++ link name and prints the result.
3007 maintenance print type Print a type chain for a given symbol
3009 * Change to .gdbinit file processing
3011 We now read the $HOME/.gdbinit file before processing the argv arguments
3012 (e.g. reading symbol files or core files). This allows global parameters to
3013 be set, which will apply during the symbol reading. The ./.gdbinit is still
3014 read after argv processing.
3016 * New hosts supported
3018 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3020 GNU/Linux support i386-unknown-linux or linux
3022 We are also including code to support the HP/PA running BSD and HPUX. This
3023 is almost guaranteed not to work, as we didn't have time to test or build it
3024 for this release. We are including it so that the more adventurous (or
3025 masochistic) of you can play with it. We also had major problems with the
3026 fact that the compiler that we got from HP doesn't support the -g option.
3029 * New targets supported
3031 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3033 * More smarts about finding #include files
3035 GDB now remembers the compilation directory for all include files, and for
3036 all files from which C is generated (like yacc and lex sources). This
3037 greatly improves GDB's ability to find yacc/lex sources, and include files,
3038 especially if you are debugging your program from a directory different from
3039 the one that contains your sources.
3041 We also fixed a bug which caused difficulty with listing and setting
3042 breakpoints in include files which contain C code. (In the past, you had to
3043 try twice in order to list an include file that you hadn't looked at before.)
3045 * Interesting infernals change
3047 GDB now deals with arbitrary numbers of sections, where the symbols for each
3048 section must be relocated relative to that section's landing place in the
3049 target's address space. This work was needed to support ELF with embedded
3050 stabs used by Solaris-2.0.
3052 * Bug fixes (of course!)
3054 There have been loads of fixes for the following things:
3055 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3056 i960, stabs, DOS(GO32), procfs, etc...
3058 See the ChangeLog for details.
3060 *** Changes in GDB-4.5:
3062 * New machines supported (host and target)
3064 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3066 SGI Irix-4.x mips-sgi-irix4 or iris4
3068 * New malloc package
3070 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3071 Mmalloc is capable of handling mutiple heaps of memory. It is also
3072 capable of saving a heap to a file, and then mapping it back in later.
3073 This can be used to greatly speedup the startup of GDB by using a
3074 pre-parsed symbol table which lives in a mmalloc managed heap. For
3075 more details, please read mmalloc/mmalloc.texi.
3079 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3080 'help info proc' for details.
3082 * MIPS ecoff symbol table format
3084 The code that reads MIPS symbol table format is now supported on all hosts.
3085 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3088 * File name changes for MS-DOS
3090 Many files in the config directories have been renamed to make it easier to
3091 support GDB on MS-DOSe systems (which have very restrictive file name
3092 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3093 environment) is close to working but has some remaining problems. Note
3094 that debugging of DOS programs is not supported, due to limitations
3095 in the ``operating system'', but it can be used to host cross-debugging.
3097 * Cross byte order fixes
3099 Many fixes have been made to support cross debugging of Sparc and MIPS
3100 targets from hosts whose byte order differs.
3102 * New -mapped and -readnow options
3104 If memory-mapped files are available on your system through the 'mmap'
3105 system call, you can use the -mapped option on the `file' or
3106 `symbol-file' commands to cause GDB to write the symbols from your
3107 program into a reusable file. If the program you are debugging is
3108 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3109 Future GDB debugging sessions will notice the presence of this file,
3110 and will quickly map in symbol information from it, rather than reading
3111 the symbol table from the executable program. Using the '-mapped'
3112 option in a GDB `file' or `symbol-file' command has the same effect as
3113 starting GDB with the '-mapped' command-line option.
3115 You can cause GDB to read the entire symbol table immediately by using
3116 the '-readnow' option with any of the commands that load symbol table
3117 information (or on the GDB command line). This makes the command
3118 slower, but makes future operations faster.
3120 The -mapped and -readnow options are typically combined in order to
3121 build a `fred.syms' file that contains complete symbol information.
3122 A simple GDB invocation to do nothing but build a `.syms' file for future
3125 gdb -batch -nx -mapped -readnow programname
3127 The `.syms' file is specific to the host machine on which GDB is run.
3128 It holds an exact image of GDB's internal symbol table. It cannot be
3129 shared across multiple host platforms.
3131 * longjmp() handling
3133 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3134 siglongjmp() without losing control. This feature has not yet been ported to
3135 all systems. It currently works on many 386 platforms, all MIPS-based
3136 platforms (SGI, DECstation, etc), and Sun3/4.
3140 Preliminary work has been put in to support the new Solaris OS from Sun. At
3141 this time, it can control and debug processes, but it is not capable of
3146 As always, many many bug fixes. The major areas were with g++, and mipsread.
3147 People using the MIPS-based platforms should experience fewer mysterious
3148 crashes and trashed symbol tables.
3150 *** Changes in GDB-4.4:
3152 * New machines supported (host and target)
3154 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3156 BSD Reno on Vax vax-dec-bsd
3157 Ultrix on Vax vax-dec-ultrix
3159 * New machines supported (target)
3161 AMD 29000 embedded, using EBMON a29k-none-none
3165 GDB continues to improve its handling of C++. `References' work better.
3166 The demangler has also been improved, and now deals with symbols mangled as
3167 per the Annotated C++ Reference Guide.
3169 GDB also now handles `stabs' symbol information embedded in MIPS
3170 `ecoff' symbol tables. Since the ecoff format was not easily
3171 extensible to handle new languages such as C++, this appeared to be a
3172 good way to put C++ debugging info into MIPS binaries. This option
3173 will be supported in the GNU C compiler, version 2, when it is
3176 * New features for SVR4
3178 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3179 shared libraries. Debugging dynamically linked programs should present
3180 only minor differences from debugging statically linked programs.
3182 The `info proc' command will print out information about any process
3183 on an SVR4 system (including the one you are debugging). At the moment,
3184 it prints the address mappings of the process.
3186 If you bring up GDB on another SVR4 system, please send mail to
3187 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3189 * Better dynamic linking support in SunOS
3191 Reading symbols from shared libraries which contain debugging symbols
3192 now works properly. However, there remain issues such as automatic
3193 skipping of `transfer vector' code during function calls, which
3194 make it harder to debug code in a shared library, than to debug the
3195 same code linked statically.
3199 GDB is now using the latest `getopt' routines from the FSF. This
3200 version accepts the -- prefix for options with long names. GDB will
3201 continue to accept the old forms (-option and +option) as well.
3202 Various single letter abbreviations for options have been explicity
3203 added to the option table so that they won't get overshadowed in the
3204 future by other options that begin with the same letter.
3208 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3209 Many assorted bugs have been handled. Many more remain to be handled.
3210 See the various ChangeLog files (primarily in gdb and bfd) for details.
3213 *** Changes in GDB-4.3:
3215 * New machines supported (host and target)
3217 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3218 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3219 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3221 * Almost SCO Unix support
3223 We had hoped to support:
3224 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3225 (except for core file support), but we discovered very late in the release
3226 that it has problems with process groups that render gdb unusable. Sorry
3227 about that. I encourage people to fix it and post the fixes.
3229 * Preliminary ELF and DWARF support
3231 GDB can read ELF object files on System V Release 4, and can handle
3232 debugging records for C, in DWARF format, in ELF files. This support
3233 is preliminary. If you bring up GDB on another SVR4 system, please
3234 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3239 GDB now uses the latest `readline' library. One user-visible change
3240 is that two tabs will list possible command completions, which previously
3241 required typing M-? (meta-question mark, or ESC ?).
3245 The `stepi' bug that many of you noticed has been squashed.
3246 Many bugs in C++ have been handled. Many more remain to be handled.
3247 See the various ChangeLog files (primarily in gdb and bfd) for details.
3249 * State of the MIPS world (in case you wondered):
3251 GDB can understand the symbol tables emitted by the compilers
3252 supplied by most vendors of MIPS-based machines, including DEC. These
3253 symbol tables are in a format that essentially nobody else uses.
3255 Some versions of gcc come with an assembler post-processor called
3256 mips-tfile. This program is required if you want to do source-level
3257 debugging of gcc-compiled programs. I believe FSF does not ship
3258 mips-tfile with gcc version 1, but it will eventually come with gcc
3261 Debugging of g++ output remains a problem. g++ version 1.xx does not
3262 really support it at all. (If you're lucky, you should be able to get
3263 line numbers and stack traces to work, but no parameters or local
3264 variables.) With some work it should be possible to improve the
3267 When gcc version 2 is released, you will have somewhat better luck.
3268 However, even then you will get confusing results for inheritance and
3271 We will eventually provide full debugging of g++ output on
3272 DECstations. This will probably involve some kind of stabs-in-ecoff
3273 encapulation, but the details have not been worked out yet.
3276 *** Changes in GDB-4.2:
3278 * Improved configuration
3280 Only one copy of `configure' exists now, and it is not self-modifying.
3281 Porting BFD is simpler.
3285 The `step' and `next' commands now only stop at the first instruction
3286 of a source line. This prevents the multiple stops that used to occur
3287 in switch statements, for-loops, etc. `Step' continues to stop if a
3288 function that has debugging information is called within the line.
3292 Lots of small bugs fixed. More remain.
3294 * New host supported (not target)
3296 Intel 386 PC clone running Mach i386-none-mach
3299 *** Changes in GDB-4.1:
3301 * Multiple source language support
3303 GDB now has internal scaffolding to handle several source languages.
3304 It determines the type of each source file from its filename extension,
3305 and will switch expression parsing and number formatting to match the
3306 language of the function in the currently selected stack frame.
3307 You can also specifically set the language to be used, with
3308 `set language c' or `set language modula-2'.
3312 GDB now has preliminary support for the GNU Modula-2 compiler,
3313 currently under development at the State University of New York at
3314 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3315 continue through the fall of 1991 and into 1992.
3317 Other Modula-2 compilers are currently not supported, and attempting to
3318 debug programs compiled with them will likely result in an error as the
3319 symbol table is read. Feel free to work on it, though!
3321 There are hooks in GDB for strict type checking and range checking,
3322 in the `Modula-2 philosophy', but they do not currently work.
3326 GDB can now write to executable and core files (e.g. patch
3327 a variable's value). You must turn this switch on, specify
3328 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3329 by assigning a new value to a variable. Modifications take
3332 * Automatic SunOS shared library reading
3334 When you run your program, GDB automatically determines where its
3335 shared libraries (if any) have been loaded, and reads their symbols.
3336 The `share' command is no longer needed. This also works when
3337 examining core files.
3341 You can specify the number of lines that the `list' command shows.
3344 * New machines supported (host and target)
3346 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3347 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3348 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3350 * New hosts supported (not targets)
3352 IBM RT/PC: romp-ibm-aix or rtpc
3354 * New targets supported (not hosts)
3356 AMD 29000 embedded with COFF a29k-none-coff
3357 AMD 29000 embedded with a.out a29k-none-aout
3358 Ultracomputer remote kernel debug a29k-nyu-kern
3360 * New remote interfaces
3366 *** Changes in GDB-4.0:
3370 Wide output is wrapped at good places to make the output more readable.
3372 Gdb now supports cross-debugging from a host machine of one type to a
3373 target machine of another type. Communication with the target system
3374 is over serial lines. The ``target'' command handles connecting to the
3375 remote system; the ``load'' command will download a program into the
3376 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3377 also supports debugging of realtime processes running under VxWorks,
3378 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3379 stub on the target system.
3381 New CPUs supported include the AMD 29000 and Intel 960.
3383 GDB now reads object files and symbol tables via a ``binary file''
3384 library, which allows a single copy of GDB to debug programs of multiple
3385 object file types such as a.out and coff.
3387 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3388 refcard.dvi and refcard.ps are available to format it).
3391 * Control-Variable user interface simplified
3393 All variables that control the operation of the debugger can be set
3394 by the ``set'' command, and displayed by the ``show'' command.
3396 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3397 ``Show prompt'' produces the response:
3398 Gdb's prompt is new-gdb=>.
3400 What follows are the NEW set commands. The command ``help set'' will
3401 print a complete list of old and new set commands. ``help set FOO''
3402 will give a longer description of the variable FOO. ``show'' will show
3403 all of the variable descriptions and their current settings.
3405 confirm on/off: Enables warning questions for operations that are
3406 hard to recover from, e.g. rerunning the program while
3407 it is already running. Default is ON.
3409 editing on/off: Enables EMACS style command line editing
3410 of input. Previous lines can be recalled with
3411 control-P, the current line can be edited with control-B,
3412 you can search for commands with control-R, etc.
3415 history filename NAME: NAME is where the gdb command history
3416 will be stored. The default is .gdb_history,
3417 or the value of the environment variable
3420 history size N: The size, in commands, of the command history. The
3421 default is 256, or the value of the environment variable
3424 history save on/off: If this value is set to ON, the history file will
3425 be saved after exiting gdb. If set to OFF, the
3426 file will not be saved. The default is OFF.
3428 history expansion on/off: If this value is set to ON, then csh-like
3429 history expansion will be performed on
3430 command line input. The default is OFF.
3432 radix N: Sets the default radix for input and output. It can be set
3433 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3434 in the current radix, so "set radix 10" is always a no-op.
3436 height N: This integer value is the number of lines on a page. Default
3437 is 24, the current `stty rows'' setting, or the ``li#''
3438 setting from the termcap entry matching the environment
3441 width N: This integer value is the number of characters on a line.
3442 Default is 80, the current `stty cols'' setting, or the ``co#''
3443 setting from the termcap entry matching the environment
3446 Note: ``set screensize'' is obsolete. Use ``set height'' and
3447 ``set width'' instead.
3449 print address on/off: Print memory addresses in various command displays,
3450 such as stack traces and structure values. Gdb looks
3451 more ``symbolic'' if you turn this off; it looks more
3452 ``machine level'' with it on. Default is ON.
3454 print array on/off: Prettyprint arrays. New convenient format! Default
3457 print demangle on/off: Print C++ symbols in "source" form if on,
3460 print asm-demangle on/off: Same, for assembler level printouts
3463 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3466 * Support for Epoch Environment.
3468 The epoch environment is a version of Emacs v18 with windowing. One
3469 new command, ``inspect'', is identical to ``print'', except that if you
3470 are running in the epoch environment, the value is printed in its own
3474 * Support for Shared Libraries
3476 GDB can now debug programs and core files that use SunOS shared libraries.
3477 Symbols from a shared library cannot be referenced
3478 before the shared library has been linked with the program (this
3479 happens after you type ``run'' and before the function main() is entered).
3480 At any time after this linking (including when examining core files
3481 from dynamically linked programs), gdb reads the symbols from each
3482 shared library when you type the ``sharedlibrary'' command.
3483 It can be abbreviated ``share''.
3485 sharedlibrary REGEXP: Load shared object library symbols for files
3486 matching a unix regular expression. No argument
3487 indicates to load symbols for all shared libraries.
3489 info sharedlibrary: Status of loaded shared libraries.
3494 A watchpoint stops execution of a program whenever the value of an
3495 expression changes. Checking for this slows down execution
3496 tremendously whenever you are in the scope of the expression, but is
3497 quite useful for catching tough ``bit-spreader'' or pointer misuse
3498 problems. Some machines such as the 386 have hardware for doing this
3499 more quickly, and future versions of gdb will use this hardware.
3501 watch EXP: Set a watchpoint (breakpoint) for an expression.
3503 info watchpoints: Information about your watchpoints.
3505 delete N: Deletes watchpoint number N (same as breakpoints).
3506 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3507 enable N: Re-enables watchpoint number N (same as breakpoints).
3510 * C++ multiple inheritance
3512 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3515 * C++ exception handling
3517 Gdb now supports limited C++ exception handling. Besides the existing
3518 ability to breakpoint on an exception handler, gdb can breakpoint on
3519 the raising of an exception (before the stack is peeled back to the
3522 catch FOO: If there is a FOO exception handler in the dynamic scope,
3523 set a breakpoint to catch exceptions which may be raised there.
3524 Multiple exceptions (``catch foo bar baz'') may be caught.
3526 info catch: Lists all exceptions which may be caught in the
3527 current stack frame.
3530 * Minor command changes
3532 The command ``call func (arg, arg, ...)'' now acts like the print
3533 command, except it does not print or save a value if the function's result
3534 is void. This is similar to dbx usage.
3536 The ``up'' and ``down'' commands now always print the frame they end up
3537 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3538 frames without printing.
3540 * New directory command
3542 'dir' now adds directories to the FRONT of the source search path.
3543 The path starts off empty. Source files that contain debug information
3544 about the directory in which they were compiled can be found even
3545 with an empty path; Sun CC and GCC include this information. If GDB can't
3546 find your source file in the current directory, type "dir .".
3548 * Configuring GDB for compilation
3550 For normal use, type ``./configure host''. See README or gdb.texinfo
3553 GDB now handles cross debugging. If you are remotely debugging between
3554 two different machines, type ``./configure host -target=targ''.
3555 Host is the machine where GDB will run; targ is the machine
3556 where the program that you are debugging will run.