1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * Tracepoints may now be conditional. The syntax is as for
7 breakpoints; either an "if" clause appended to the "trace" command,
8 or the "condition" command is available. GDB sends the condition to
9 the target for evaluation using the same bytecode format as is used
10 for tracepoint actions.
12 * "disassemble" command with a /r modifier, print the raw instructions
13 in hex as well as in symbolic form."
15 * Process record and replay
17 In a architecture environment that supports ``process record and
18 replay'', ``process record and replay'' target can record a log of
19 the process execution, and replay it with both forward and reverse
22 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
23 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
24 set execution-direction {forward|reverse}, for targets that support
27 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
28 feature is available with a native GDB running on kernel version
31 * GDB now has support for multi-byte and wide character sets on the
32 target. Strings whose character type is wchar_t, char16_t, or
33 char32_t are now correctly printed. GDB supports wide- and unicode-
34 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
35 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
36 `printf'. This feature requires iconv to work properly; if your
37 system does not have a working iconv, GDB can use GNU libiconv. See
38 the installation instructions for more information.
40 * GDB now supports automatic retrieval of shared library files from
41 remote targets. To use this feature, specify a system root that begins
42 with the `remote:' prefix, either via the `set sysroot' command or via
43 the `--with-sysroot' configure-time option.
45 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
46 now complete on file names.
48 * When completing in expressions, gdb will attempt to limit
49 completions to allowable structure or union fields, where appropriate.
50 For instance, consider:
52 # struct example { int f1; double f2; };
53 # struct example variable;
56 If the user types TAB at the end of this command line, the available
57 completions will be "f1" and "f2".
59 * Inlined functions are now supported. They show up in backtraces, and
60 the "step", "next", and "finish" commands handle them automatically.
62 * GDB now supports the token-splicing (##) and stringification (#)
63 operators when expanding macros. It also supports variable-arity
66 * GDB now supports inspecting extra signal information, exported by
67 the new $_siginfo convenience variable. The feature is currently
68 implemented on linux ARM, i386 and amd64.
70 * GDB can now display the VFP floating point registers and NEON vector
71 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
72 can provide these registers (requires Linux 2.6.30 or later). Remote
73 and simulator targets may also provide them.
78 Search memory for a sequence of bytes.
81 Turn off `+'/`-' protocol acknowledgments to permit more efficient
82 operation over reliable transport links. Use of this packet is
83 controlled by the `set remote noack-packet' command.
86 Kill the process with the specified process ID. Use this in preference
87 to `k' when multiprocess protocol extensions are supported.
90 Obtains additional operating system information
94 Read or write additional signal information.
96 * Removed remote protocol undocumented extension
98 An undocumented extension to the remote protocol's `S' stop reply
99 packet that permited the stub to pass a process id was removed.
100 Remote servers should use the `T' stop reply packet instead.
102 * The "disassemble" command now supports an optional /m modifier to print mixed
105 * GDB now supports multiple function calling conventions according to the
106 DWARF-2 DW_AT_calling_convention function attribute.
108 * The SH target utilizes the aforementioned change to distinguish between gcc
109 and Renesas calling convention. It also adds the new CLI commands
110 `set/show sh calling-convention'.
112 * GDB can now read compressed debug sections, as produced by GNU gold
113 with the --compress-debug-sections=zlib flag.
115 * 64-bit core files are now supported on AIX.
117 * Thread switching is now supported on Tru64.
119 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
120 which will be allocated using malloc later in program execution.
122 * The qXfer:libraries:read remote procotol packet now allows passing a
123 list of section offsets.
125 * On GNU/Linux, GDB can now attach to stopped processes. Several race
126 conditions handling signals delivered during attach or thread creation
127 have also been fixed.
129 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
130 From the user's standpoint, all unqualified instances of True and False
131 are treated as the standard definitions, regardless of context.
133 * GDB now parses C++ symbol and type names more flexibly. For
136 template<typename T> class C { };
139 GDB will now correctly handle all of:
141 ptype C<char const *>
143 ptype C<const char *>
146 * New features in the GDB remote stub, gdbserver
148 - The "--wrapper" command-line argument tells gdbserver to use a
149 wrapper program to launch programs for debugging.
151 - On PowerPC and S/390 targets, it is now possible to use a single
152 gdbserver executable to debug both 32-bit and 64-bit programs.
153 (This requires gdbserver itself to be built as a 64-bit executable.)
155 - gdbserver uses the new noack protocol mode for TCP connections to
156 reduce communications latency, if also supported and enabled in GDB.
158 - Support for the sparc64-linux-gnu target is now included in
161 - The amd64-linux build of gdbserver now supports debugging both
162 32-bit and 64-bit programs.
164 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
165 now support hardware watchpoints, and will use them automatically
170 GDB now has support for scripting using Python. Whether this is
171 available is determined at configure time.
173 New GDB commands can now be written in Python.
175 * Ada tasking support
177 Ada tasks can now be inspected in GDB. The following commands have
181 Print the list of Ada tasks.
183 Print detailed information about task number N.
185 Print the task number of the current task.
187 Switch the context of debugging to task number N.
189 * Support for user-defined prefixed commands. The "define" command can
190 add new commands to existing prefixes, e.g. "target".
192 * Multi-inferior, multi-process debugging.
194 GDB now has generalized support for multi-inferior debugging. See
195 "Debugging Multiple Inferiors" in the manual for more information.
196 Although availability still depends on target support, the command
197 set is more uniform now. The GNU/Linux specific multi-forks support
198 has been migrated to this new framework. This implied some user
199 visible changes; see "New commands" and also "Removed commands"
202 * Target descriptions can now describe the target OS ABI. See the
203 "Target Description Format" section in the user manual for more
206 * New commands (for set/show, see "New options" below)
208 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
210 Search memory for a sequence of bytes.
212 maint set python print-stack
213 maint show python print-stack
214 Show a stack trace when an error is encountered in a Python script.
217 Invoke CODE by passing it to the Python interpreter.
222 These allow macros to be defined, undefined, and listed
226 Show operating system information about processes.
229 List the inferiors currently under GDB's control.
232 Switch focus to inferior number NUM.
235 Detach from inferior number NUM.
238 Kill inferior number NUM.
242 set sh calling-convention
243 show sh calling-convention
244 Control the calling convention used when calling SH target functions.
246 set print symbol-loading
247 show print symbol-loading
248 Control printing of symbol loading messages.
252 Control display of timestamps with GDB debugging output.
254 set disassemble-next-line
255 show disassemble-next-line
256 Control display of disassembled source lines or instructions when
259 set remote noack-packet
260 show remote noack-packet
261 Set/show the use of remote protocol QStartNoAckMode packet. See above
262 under "New remote packets."
264 set remote query-attached-packet
265 show remote query-attached-packet
266 Control use of remote protocol `qAttached' (query-attached) packet.
268 set remote read-siginfo-object
269 show remote read-siginfo-object
270 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
273 set remote write-siginfo-object
274 show remote write-siginfo-object
275 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
278 set displaced-stepping
279 show displaced-stepping
280 Control displaced stepping mode. Displaced stepping is a way to
281 single-step over breakpoints without removing them from the debuggee.
282 Also known as "out-of-line single-stepping".
286 Control display of debugging info for displaced stepping.
288 maint set internal-error
289 maint show internal-error
290 Control what GDB does when an internal error is detected.
292 maint set internal-warning
293 maint show internal-warning
294 Control what GDB does when an internal warning is detected.
299 Use a wrapper program to launch programs for debugging.
301 set multiple-symbols (all|ask|cancel)
302 show multiple-symbols
303 The value of this variable can be changed to adjust the debugger behavior
304 when an expression or a breakpoint location contains an ambiguous symbol
305 name (an overloaded function name, for instance).
307 set breakpoint always-inserted
308 show breakpoint always-inserted
309 Keep breakpoints always inserted in the target, as opposed to inserting
310 them when resuming the target, and removing them when the target stops.
311 This option can improve debugger performance on slow remote targets.
313 set arm fallback-mode (arm|thumb|auto)
314 show arm fallback-mode
315 set arm force-mode (arm|thumb|auto)
317 These commands control how ARM GDB determines whether instructions
318 are ARM or Thumb. The default for both settings is auto, which uses
319 the current CPSR value for instructions without symbols; previous
320 versions of GDB behaved as if "set arm fallback-mode arm".
322 set disable-randomization
323 show disable-randomization
324 Standalone programs run with the virtual address space randomization enabled
325 by default on some platforms. This option keeps the addresses stable across
326 multiple debugging sessions.
330 Control whether other threads are stopped or not when some thread hits
335 Requests that asynchronous execution is enabled in the target, if available.
336 In this case, it's possible to resume target in the background, and interact
337 with GDB while the target is running. "show target-async" displays the
338 current state of asynchronous execution of the target.
340 set target-wide-charset
341 show target-wide-charset
342 The target-wide-charset is the name of the character set that GDB
343 uses when printing characters whose type is wchar_t.
345 set tcp auto-retry (on|off)
347 set tcp connect-timeout
348 show tcp connect-timeout
349 These commands allow GDB to retry failed TCP connections to a remote stub
350 with a specified timeout period; this is useful if the stub is launched
351 in parallel with GDB but may not be ready to accept connections immediately.
353 set libthread-db-search-path
354 show libthread-db-search-path
355 Control list of directories which GDB will search for appropriate
358 set schedule-multiple (on|off)
359 show schedule-multiple
360 Allow GDB to resume all threads of all processes or only threads of
366 For program forks, this is replaced by the new more generic `info
367 inferiors' command. To list checkpoints, you can still use the
368 `info checkpoints' command, which was an alias for the `info forks'
372 Replaced by the new `inferior' command. To switch between
373 checkpoints, you can still use the `restart' command, which was an
374 alias for the `fork' command.
377 This is removed, since some targets don't have a notion of
378 processes. To switch between processes, you can still use the
379 `inferior' command using GDB's own inferior number.
382 For program forks, this is replaced by the new more generic `kill
383 inferior' command. To delete a checkpoint, you can still use the
384 `delete checkpoint' command, which was an alias for the `delete
388 For program forks, this is replaced by the new more generic `detach
389 inferior' command. To detach a checkpoint, you can still use the
390 `detach checkpoint' command, which was an alias for the `detach
393 * New native configurations
395 x86/x86_64 Darwin i[34567]86-*-darwin*
397 x86_64 MinGW x86_64-*-mingw*
401 Lattice Mico32 lm32-*
402 x86 DICOS i[34567]86-*-dicos*
403 x86_64 DICOS x86_64-*-dicos*
405 * The GDB remote stub, gdbserver, now supports x86 Windows CE
406 (mingw32ce) debugging.
412 These commands were actually not implemented on any target.
414 *** Changes in GDB 6.8
416 * New native configurations
418 NetBSD/hppa hppa*-*netbsd*
419 Xtensa GNU/Linux xtensa*-*-linux*
423 NetBSD/hppa hppa*-*-netbsd*
424 Xtensa GNU/Lunux xtensa*-*-linux*
426 * Change in command line behavior -- corefiles vs. process ids.
428 When the '-p NUMBER' or '--pid NUMBER' options are used, and
429 attaching to process NUMBER fails, GDB no longer attempts to open a
430 core file named NUMBER. Attaching to a program using the -c option
431 is no longer supported. Instead, use the '-p' or '--pid' options.
433 * GDB can now be built as a native debugger for debugging Windows x86
434 (mingw32) Portable Executable (PE) programs.
436 * Pending breakpoints no longer change their number when their address
439 * GDB now supports breakpoints with multiple locations,
440 including breakpoints on C++ constructors, inside C++ templates,
441 and in inlined functions.
443 * GDB's ability to debug optimized code has been improved. GDB more
444 accurately identifies function bodies and lexical blocks that occupy
445 more than one contiguous range of addresses.
447 * Target descriptions can now describe registers for PowerPC.
449 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
450 registers on PowerPC targets.
452 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
453 targets even when the libthread_db library is not available.
455 * The GDB remote stub, gdbserver, now supports the new file transfer
456 commands (remote put, remote get, and remote delete).
458 * The GDB remote stub, gdbserver, now supports run and attach in
459 extended-remote mode.
461 * hppa*64*-*-hpux11* target broken
462 The debugger is unable to start a program and fails with the following
463 error: "Error trying to get information about dynamic linker".
464 The gdb-6.7 release is also affected.
466 * GDB now supports the --enable-targets= configure option to allow
467 building a single GDB executable that supports multiple remote
468 target architectures.
470 * GDB now supports debugging C and C++ programs which use the
471 Decimal Floating Point extension. In addition, the PowerPC target
472 now has a set of pseudo-registers to inspect decimal float values
473 stored in two consecutive float registers.
475 * The -break-insert MI command can optionally create pending
478 * Improved support for debugging Ada
479 Many improvements to the Ada language support have been made. These
481 - Better support for Ada2005 interface types
482 - Improved handling of arrays and slices in general
483 - Better support for Taft-amendment types
484 - The '{type} ADDRESS' expression is now allowed on the left hand-side
486 - Improved command completion in Ada
489 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
494 set print frame-arguments (all|scalars|none)
495 show print frame-arguments
496 The value of this variable can be changed to control which argument
497 values should be printed by the debugger when displaying a frame.
502 Transfer files to and from a remote target, and delete remote files.
509 Transfer files to and from a remote target, and delete remote files.
518 Open, close, read, write, and delete files on the remote system.
521 Attach to an existing process on the remote system, in extended-remote
525 Run a new process on the remote system, in extended-remote mode.
527 *** Changes in GDB 6.7
529 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
530 bfd, libiberty and opcodes, as revealed by static analysis donated by
531 Coverity, Inc. (http://scan.coverity.com).
533 * When looking up multiply-defined global symbols, GDB will now prefer the
534 symbol definition in the current shared library if it was built using the
535 -Bsymbolic linker option.
537 * When the Text User Interface (TUI) is not configured, GDB will now
538 recognize the -tui command-line option and print a message that the TUI
541 * The GDB remote stub, gdbserver, now has lower overhead for high
542 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
544 * GDB for MIPS targets now autodetects whether a remote target provides
545 32-bit or 64-bit register values.
547 * Support for C++ member pointers has been improved.
549 * GDB now understands XML target descriptions, which specify the
550 target's overall architecture. GDB can read a description from
551 a local file or over the remote serial protocol.
553 * Vectors of single-byte data use a new integer type which is not
554 automatically displayed as character or string data.
556 * The /s format now works with the print command. It displays
557 arrays of single-byte integers and pointers to single-byte integers
560 * Target descriptions can now describe target-specific registers,
561 for architectures which have implemented the support (currently
562 only ARM, M68K, and MIPS).
564 * GDB and the GDB remote stub, gdbserver, now support the XScale
567 * The GDB remote stub, gdbserver, has been updated to support
568 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
569 has been rewritten to use the standard GDB remote protocol.
571 * GDB can now step into C++ functions which are called through thunks.
573 * GDB for the Cell/B.E. SPU now supports overlay debugging.
575 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
576 layout. It also supports a TextSeg= and DataSeg= response when only
577 segment base addresses (rather than offsets) are available.
579 * The /i format now outputs any trailing branch delay slot instructions
580 immediately following the last instruction within the count specified.
582 * The GDB remote protocol "T" stop reply packet now supports a
583 "library" response. Combined with the new "qXfer:libraries:read"
584 packet, this response allows GDB to debug shared libraries on targets
585 where the operating system manages the list of loaded libraries (e.g.
586 Windows and SymbianOS).
588 * The GDB remote stub, gdbserver, now supports dynamic link libraries
589 (DLLs) on Windows and Windows CE targets.
591 * GDB now supports a faster verification that a .debug file matches its binary
592 according to its build-id signature, if the signature is present.
598 Enable or disable hardware flow control (RTS/CTS) on the serial port
599 when debugging using remote targets.
601 set mem inaccessible-by-default
602 show mem inaccessible-by-default
603 If the target supplies a memory map, for instance via the remote
604 protocol's "qXfer:memory-map:read" packet, setting this variable
605 prevents GDB from accessing memory outside the memory map. This
606 is useful for targets with memory mapped registers or which react
607 badly to accesses of unmapped address space.
609 set breakpoint auto-hw
610 show breakpoint auto-hw
611 If the target supplies a memory map, for instance via the remote
612 protocol's "qXfer:memory-map:read" packet, setting this variable
613 lets GDB use hardware breakpoints automatically for memory regions
614 where it can not use software breakpoints. This covers both the
615 "break" command and internal breakpoints used for other commands
616 including "next" and "finish".
619 catch exception unhandled
620 Stop the program execution when Ada exceptions are raised.
623 Stop the program execution when an Ada assertion failed.
627 Set an alternate system root for target files. This is a more
628 general version of "set solib-absolute-prefix", which is now
629 an alias to "set sysroot".
632 Provide extended SPU facility status information. This set of
633 commands is available only when debugging the Cell/B.E. SPU
636 * New native configurations
638 OpenBSD/sh sh*-*openbsd*
643 Use the specified local file as an XML target description, and do
644 not query the target for its built-in description.
648 OpenBSD/sh sh*-*-openbsd*
649 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
650 Toshiba Media Processor mep-elf
655 Ignore the specified signals; pass them directly to the debugged program
656 without stopping other threads or reporting them to GDB.
659 Read an XML target description from the target, which describes its
664 Read or write contents of an spufs file on the target system. These
665 packets are available only on the Cell/B.E. SPU architecture.
667 qXfer:libraries:read:
668 Report the loaded shared libraries. Combined with new "T" packet
669 response, this packet allows GDB to debug shared libraries on
670 targets where the operating system manages the list of loaded
671 libraries (e.g. Windows and SymbianOS).
675 Support for these obsolete configurations has been removed.
684 i[34567]86-*-netware*
685 i[34567]86-*-sco3.2v5*
686 i[34567]86-*-sco3.2v4*
688 i[34567]86-*-sysv4.2*
691 i[34567]86-*-unixware2*
692 i[34567]86-*-unixware*
701 * Other removed features
708 Various m68k-only ROM monitors.
715 Various Renesas ROM monitors and debugging interfaces for SH and
720 Support for a Macraigor serial interface to on-chip debugging.
721 GDB does not directly support the newer parallel or USB
726 A debug information format. The predecessor to DWARF 2 and
727 DWARF 3, which are still supported.
729 Support for the HP aCC compiler on HP-UX/PA-RISC
731 SOM-encapsulated symbolic debugging information, automatic
732 invocation of pxdb, and the aCC custom C++ ABI. This does not
733 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
734 with aCC can still be debugged on an assembly level.
738 A MIPS-specific format used to describe stack frame layout
739 in debugging information.
743 GDB could work with an older version of Guile to debug
744 the interpreter and Scheme programs running in it.
746 set mips stack-arg-size
747 set mips saved-gpreg-size
749 Use "set mips abi" to control parameter passing for MIPS.
751 *** Changes in GDB 6.6
756 Cell Broadband Engine SPU spu-elf
758 * GDB can now be configured as a cross-debugger targeting native Windows
759 (mingw32) or Cygwin. It can communicate with a remote debugging stub
760 running on a Windows system over TCP/IP to debug Windows programs.
762 * The GDB remote stub, gdbserver, has been updated to support Windows and
763 Cygwin debugging. Both single-threaded and multi-threaded programs are
766 * The "set trust-readonly-sections" command works again. This command was
767 broken in GDB 6.3, 6.4, and 6.5.
769 * The "load" command now supports writing to flash memory, if the remote
770 stub provides the required support.
772 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
773 longer requires symbolic debug information (e.g. DWARF-2).
778 unset substitute-path
780 Manage a list of substitution rules that GDB uses to rewrite the name
781 of the directories where the sources are located. This can be useful
782 for instance when the sources were moved to a different location
783 between compilation and debugging.
787 Print each CLI command as it is executed. Each command is prefixed with
788 a number of `+' symbols representing the nesting depth.
789 The source command now has a `-v' option to enable the same feature.
793 The ARM Demon monitor support (RDP protocol, "target rdp").
795 Kernel Object Display, an embedded debugging feature which only worked with
796 an obsolete version of Cisco IOS.
798 The 'set download-write-size' and 'show download-write-size' commands.
803 Tell a stub about GDB client features, and request remote target features.
804 The first feature implemented is PacketSize, which allows the target to
805 specify the size of packets it can handle - to minimize the number of
806 packets required and improve performance when connected to a remote
810 Fetch an OS auxilliary vector from the remote stub. This packet is a
811 more efficient replacement for qPart:auxv:read.
813 qXfer:memory-map:read:
814 Fetch a memory map from the remote stub, including information about
815 RAM, ROM, and flash memory devices.
820 Erase and program a flash memory device.
822 * Removed remote packets
825 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
826 used it, and only gdbserver implemented it.
828 *** Changes in GDB 6.5
832 Renesas M32C/M16C m32c-elf
834 Morpho Technologies ms1 ms1-elf
838 init-if-undefined Initialize a convenience variable, but
839 only if it doesn't already have a value.
841 The following commands are presently only implemented for native GNU/Linux:
843 checkpoint Save a snapshot of the program state.
845 restart <n> Return the program state to a
846 previously saved state.
848 info checkpoints List currently saved checkpoints.
850 delete-checkpoint <n> Delete a previously saved checkpoint.
852 set|show detach-on-fork Tell gdb whether to detach from a newly
853 forked process, or to keep debugging it.
855 info forks List forks of the user program that
856 are available to be debugged.
858 fork <n> Switch to debugging one of several
859 forks of the user program that are
860 available to be debugged.
862 delete-fork <n> Delete a fork from the list of forks
863 that are available to be debugged (and
864 kill the forked process).
866 detach-fork <n> Delete a fork from the list of forks
867 that are available to be debugged (and
868 allow the process to continue).
872 Morpho Technologies ms2 ms1-elf
874 * Improved Windows host support
876 GDB now builds as a cross debugger hosted on i686-mingw32, including
877 native console support, and remote communications using either
878 network sockets or serial ports.
880 * Improved Modula-2 language support
882 GDB can now print most types in the Modula-2 syntax. This includes:
883 basic types, set types, record types, enumerated types, range types,
884 pointer types and ARRAY types. Procedure var parameters are correctly
885 printed and hexadecimal addresses and character constants are also
886 written in the Modula-2 syntax. Best results can be obtained by using
887 GNU Modula-2 together with the -gdwarf-2 command line option.
891 The ARM rdi-share module.
893 The Netware NLM debug server.
895 *** Changes in GDB 6.4
897 * New native configurations
899 OpenBSD/arm arm*-*-openbsd*
900 OpenBSD/mips64 mips64-*-openbsd*
904 Morpho Technologies ms1 ms1-elf
906 * New command line options
908 --batch-silent As for --batch, but totally silent.
909 --return-child-result The debugger will exist with the same value
910 the child (debugged) program exited with.
911 --eval-command COMMAND, -ex COMMAND
912 Execute a single GDB CLI command. This may be
913 specified multiple times and in conjunction
914 with the --command (-x) option.
916 * Deprecated commands removed
918 The following commands, that were deprecated in 2000, have been
922 set|show arm disassembly-flavor set|show arm disassembler
923 othernames set arm disassembler
924 set|show remotedebug set|show debug remote
925 set|show archdebug set|show debug arch
926 set|show eventdebug set|show debug event
929 * New BSD user-level threads support
931 It is now possible to debug programs using the user-level threads
932 library on OpenBSD and FreeBSD. Currently supported (target)
935 FreeBSD/amd64 x86_64-*-freebsd*
936 FreeBSD/i386 i386-*-freebsd*
937 OpenBSD/i386 i386-*-openbsd*
939 Note that the new kernel threads libraries introduced in FreeBSD 5.x
940 are not yet supported.
942 * New support for Matsushita MN10300 w/sim added
943 (Work in progress). mn10300-elf.
945 * REMOVED configurations and files
947 VxWorks and the XDR protocol *-*-vxworks
948 Motorola MCORE mcore-*-*
949 National Semiconductor NS32000 ns32k-*-*
951 * New "set print array-indexes" command
953 After turning this setting "on", GDB prints the index of each element
954 when displaying arrays. The default is "off" to preserve the previous
957 * VAX floating point support
959 GDB now supports the not-quite-ieee VAX F and D floating point formats.
961 * User-defined command support
963 In addition to using $arg0..$arg9 for argument passing, it is now possible
964 to use $argc to determine now many arguments have been passed. See the
965 section on user-defined commands in the user manual for more information.
967 *** Changes in GDB 6.3:
969 * New command line option
971 GDB now accepts -l followed by a number to set the timeout for remote
974 * GDB works with GCC -feliminate-dwarf2-dups
976 GDB now supports a more compact representation of DWARF-2 debug
977 information using DW_FORM_ref_addr references. These are produced
978 by GCC with the option -feliminate-dwarf2-dups and also by some
979 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
980 to use -feliminate-dwarf2-dups.
982 * Internationalization
984 When supported by the host system, GDB will be built with
985 internationalization (libintl). The task of marking up the sources is
986 continued, we're looking forward to our first translation.
990 Initial support for debugging programs compiled with the GNAT
991 implementation of the Ada programming language has been integrated
992 into GDB. In this release, support is limited to expression evaluation.
994 * New native configurations
996 GNU/Linux/m32r m32r-*-linux-gnu
1000 GDB's remote protocol now includes support for the 'p' packet. This
1001 packet is used to fetch individual registers from a remote inferior.
1003 * END-OF-LIFE registers[] compatibility module
1005 GDB's internal register infrastructure has been completely rewritten.
1006 The new infrastructure making possible the implementation of key new
1007 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1010 GDB 6.3 will be the last release to include the the registers[]
1011 compatibility module that allowed out-of-date configurations to
1012 continue to work. This change directly impacts the following
1022 powerpc bdm protocol
1024 Unless there is activity to revive these configurations, they will be
1025 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1027 * OBSOLETE configurations and files
1029 Configurations that have been declared obsolete in this release have
1030 been commented out. Unless there is activity to revive these
1031 configurations, the next release of GDB will have their sources
1032 permanently REMOVED.
1041 *** Changes in GDB 6.2.1:
1043 * MIPS `break main; run' gave an heuristic-fence-post warning
1045 When attempting to run even a simple program, a warning about
1046 heuristic-fence-post being hit would be reported. This problem has
1049 * MIPS IRIX 'long double' crashed GDB
1051 When examining a long double variable, GDB would get a segmentation
1052 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1053 IRIX long double values).
1057 A bug in the VAX stack code was causing problems with the "next"
1058 command. This problem has been fixed.
1060 *** Changes in GDB 6.2:
1062 * Fix for ``many threads''
1064 On GNU/Linux systems that use the NPTL threads library, a program
1065 rapidly creating and deleting threads would confuse GDB leading to the
1068 ptrace: No such process.
1069 thread_db_get_info: cannot get thread info: generic error
1071 This problem has been fixed.
1073 * "-async" and "-noasync" options removed.
1075 Support for the broken "-noasync" option has been removed (it caused
1078 * New ``start'' command.
1080 This command runs the program until the begining of the main procedure.
1082 * New BSD Kernel Data Access Library (libkvm) interface
1084 Using ``target kvm'' it is now possible to debug kernel core dumps and
1085 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1086 platforms. Currently supported (native-only) configurations are:
1088 FreeBSD/amd64 x86_64-*-freebsd*
1089 FreeBSD/i386 i?86-*-freebsd*
1090 NetBSD/i386 i?86-*-netbsd*
1091 NetBSD/m68k m68*-*-netbsd*
1092 NetBSD/sparc sparc-*-netbsd*
1093 OpenBSD/amd64 x86_64-*-openbsd*
1094 OpenBSD/i386 i?86-*-openbsd*
1095 OpenBSD/m68k m68*-openbsd*
1096 OpenBSD/sparc sparc-*-openbsd*
1098 * Signal trampoline code overhauled
1100 Many generic problems with GDB's signal handling code have been fixed.
1101 These include: backtraces through non-contiguous stacks; recognition
1102 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1103 call; backtrace through a signal trampoline; step into and out of
1104 signal handlers; and single-stepping in the signal trampoline.
1106 Please note that kernel bugs are a limiting factor here. These
1107 features have been shown to work on an s390 GNU/Linux system that
1108 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1110 * Cygwin support for DWARF 2 added.
1112 * New native configurations
1114 GNU/Linux/hppa hppa*-*-linux*
1115 OpenBSD/hppa hppa*-*-openbsd*
1116 OpenBSD/m68k m68*-*-openbsd*
1117 OpenBSD/m88k m88*-*-openbsd*
1118 OpenBSD/powerpc powerpc-*-openbsd*
1119 NetBSD/vax vax-*-netbsd*
1120 OpenBSD/vax vax-*-openbsd*
1122 * END-OF-LIFE frame compatibility module
1124 GDB's internal frame infrastructure has been completely rewritten.
1125 The new infrastructure making it possible to support key new features
1126 including DWARF 2 Call Frame Information. To aid in the task of
1127 migrating old configurations to this new infrastructure, a
1128 compatibility module, that allowed old configurations to continue to
1129 work, was also included.
1131 GDB 6.2 will be the last release to include this frame compatibility
1132 module. This change directly impacts the following configurations:
1142 Unless there is activity to revive these configurations, they will be
1143 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1145 * REMOVED configurations and files
1147 Sun 3, running SunOS 3 m68*-*-sunos3*
1148 Sun 3, running SunOS 4 m68*-*-sunos4*
1149 Sun 2, running SunOS 3 m68000-*-sunos3*
1150 Sun 2, running SunOS 4 m68000-*-sunos4*
1151 Motorola 680x0 running LynxOS m68*-*-lynxos*
1152 AT&T 3b1/Unix pc m68*-att-*
1153 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1154 decstation mips-dec-* mips-little-*
1155 riscos mips-*-riscos* mips-*-sysv*
1156 sonymips mips-sony-*
1157 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1159 *** Changes in GDB 6.1.1:
1161 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1163 The TUI (Text-mode User Interface) is now built as part of a default
1164 GDB configuration. It is enabled by either selecting the TUI with the
1165 command line option "-i=tui" or by running the separate "gdbtui"
1166 program. For more information on the TUI, see the manual "Debugging
1169 * Pending breakpoint support (also included in GDB 6.1)
1171 Support has been added to allow you to specify breakpoints in shared
1172 libraries that have not yet been loaded. If a breakpoint location
1173 cannot be found, and the "breakpoint pending" option is set to auto,
1174 GDB queries you if you wish to make the breakpoint pending on a future
1175 shared-library load. If and when GDB resolves the breakpoint symbol,
1176 the pending breakpoint is removed as one or more regular breakpoints
1179 Pending breakpoints are very useful for GCJ Java debugging.
1181 * Fixed ISO-C build problems
1183 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1184 non ISO-C code that stopped them being built using a more strict ISO-C
1185 compiler (e.g., IBM's C compiler).
1187 * Fixed build problem on IRIX 5
1189 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1190 wasn't able to compile compile on an IRIX 5 system.
1192 * Added execute permission to gdb/gdbserver/configure
1194 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1195 permission. This bug would cause configure to fail on a number of
1196 systems (Solaris, IRIX). Ref: server/519.
1198 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1200 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1201 has been updated to use constant array sizes.
1203 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1205 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1206 its generated DWARF Call Frame Info. This encoding was causing GDB to
1207 panic, that panic has been fixed. Ref: gdb/1628.
1209 * Fixed a problem when examining parameters in shared library code.
1211 When examining parameters in optimized shared library code generated
1212 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1213 not available''. GDB now correctly displays the variable's value.
1215 *** Changes in GDB 6.1:
1217 * Removed --with-mmalloc
1219 Support for the mmalloc memory manager has been removed, as it
1220 conflicted with the internal gdb byte cache.
1222 * Changes in AMD64 configurations
1224 The AMD64 target now includes the %cs and %ss registers. As a result
1225 the AMD64 remote protocol has changed; this affects the floating-point
1226 and SSE registers. If you rely on those registers for your debugging,
1227 you should upgrade gdbserver on the remote side.
1229 * Revised SPARC target
1231 The SPARC target has been completely revised, incorporating the
1232 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1233 support for LynxOS and SunOS 4 has been dropped. Calling functions
1234 from within GDB on operating systems with a non-executable stack
1235 (Solaris, OpenBSD) now works.
1239 GDB has a new C++ demangler which does a better job on the mangled
1240 names generated by current versions of g++. It also runs faster, so
1241 with this and other changes gdb should now start faster on large C++
1244 * DWARF 2 Location Expressions
1246 GDB support for location expressions has been extended to support function
1247 arguments and frame bases. Older versions of GDB could crash when they
1250 * C++ nested types and namespaces
1252 GDB's support for nested types and namespaces in C++ has been
1253 improved, especially if you use the DWARF 2 debugging format. (This
1254 is the default for recent versions of GCC on most platforms.)
1255 Specifically, if you have a class "Inner" defined within a class or
1256 namespace "Outer", then GDB realizes that the class's name is
1257 "Outer::Inner", not simply "Inner". This should greatly reduce the
1258 frequency of complaints about not finding RTTI symbols. In addition,
1259 if you are stopped at inside of a function defined within a namespace,
1260 GDB modifies its name lookup accordingly.
1262 * New native configurations
1264 NetBSD/amd64 x86_64-*-netbsd*
1265 OpenBSD/amd64 x86_64-*-openbsd*
1266 OpenBSD/alpha alpha*-*-openbsd*
1267 OpenBSD/sparc sparc-*-openbsd*
1268 OpenBSD/sparc64 sparc64-*-openbsd*
1270 * New debugging protocols
1272 M32R with SDI protocol m32r-*-elf*
1274 * "set prompt-escape-char" command deleted.
1276 The command "set prompt-escape-char" has been deleted. This command,
1277 and its very obscure effet on GDB's prompt, was never documented,
1278 tested, nor mentioned in the NEWS file.
1280 * OBSOLETE configurations and files
1282 Configurations that have been declared obsolete in this release have
1283 been commented out. Unless there is activity to revive these
1284 configurations, the next release of GDB will have their sources
1285 permanently REMOVED.
1287 Sun 3, running SunOS 3 m68*-*-sunos3*
1288 Sun 3, running SunOS 4 m68*-*-sunos4*
1289 Sun 2, running SunOS 3 m68000-*-sunos3*
1290 Sun 2, running SunOS 4 m68000-*-sunos4*
1291 Motorola 680x0 running LynxOS m68*-*-lynxos*
1292 AT&T 3b1/Unix pc m68*-att-*
1293 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1294 decstation mips-dec-* mips-little-*
1295 riscos mips-*-riscos* mips-*-sysv*
1296 sonymips mips-sony-*
1297 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1299 * REMOVED configurations and files
1301 SGI Irix-4.x mips-sgi-irix4 or iris4
1302 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1303 Z8000 simulator z8k-zilog-none or z8ksim
1304 Matsushita MN10200 w/simulator mn10200-*-*
1305 H8/500 simulator h8500-hitachi-hms or h8500hms
1306 HP/PA running BSD hppa*-*-bsd*
1307 HP/PA running OSF/1 hppa*-*-osf*
1308 HP/PA Pro target hppa*-*-pro*
1309 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1310 386BSD i[3456]86-*-bsd*
1311 Sequent family i[3456]86-sequent-sysv4*
1312 i[3456]86-sequent-sysv*
1313 i[3456]86-sequent-bsd*
1314 SPARC running LynxOS sparc-*-lynxos*
1315 SPARC running SunOS 4 sparc-*-sunos4*
1316 Tsqware Sparclet sparclet-*-*
1317 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1319 *** Changes in GDB 6.0:
1323 Support for debugging the Objective-C programming language has been
1324 integrated into GDB.
1326 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1328 DWARF 2's Call Frame Information makes available compiler generated
1329 information that more exactly describes the program's run-time stack.
1330 By using this information, GDB is able to provide more robust stack
1333 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1334 have been updated to use a new backtrace mechanism which includes
1335 DWARF 2 CFI support.
1339 GDB's remote protocol has been extended to include support for hosted
1340 file I/O (where the remote target uses GDB's file system). See GDB's
1341 remote protocol documentation for details.
1343 * All targets using the new architecture framework.
1345 All of GDB's targets have been updated to use the new internal
1346 architecture framework. The way is now open for future GDB releases
1347 to include cross-architecture native debugging support (i386 on amd64,
1350 * GNU/Linux's Thread Local Storage (TLS)
1352 GDB now includes support for for the GNU/Linux implementation of
1353 per-thread variables.
1355 * GNU/Linux's Native POSIX Thread Library (NPTL)
1357 GDB's thread code has been updated to work with either the new
1358 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1360 * Separate debug info.
1362 GDB, in conjunction with BINUTILS, now supports a mechanism for
1363 automatically loading debug information from a separate file. Instead
1364 of shipping full debug and non-debug versions of system libraries,
1365 system integrators can now instead ship just the stripped libraries
1366 and optional debug files.
1368 * DWARF 2 Location Expressions
1370 DWARF 2 Location Expressions allow the compiler to more completely
1371 describe the location of variables (even in optimized code) to the
1374 GDB now includes preliminary support for location expressions (support
1375 for DW_OP_piece is still missing).
1379 A number of long standing bugs that caused GDB to die while starting a
1380 Java application have been fixed. GDB's Java support is now
1381 considered "useable".
1383 * GNU/Linux support for fork, vfork, and exec.
1385 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1386 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1389 * GDB supports logging output to a file
1391 There are two new commands, "set logging" and "show logging", which can be
1392 used to capture GDB's output to a file.
1394 * The meaning of "detach" has changed for gdbserver
1396 The "detach" command will now resume the application, as documented. To
1397 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1400 * d10v, m68hc11 `regs' command deprecated
1402 The `info registers' command has been updated so that it displays the
1403 registers using a format identical to the old `regs' command.
1407 A new command, "maint set profile on/off", has been added. This command can
1408 be used to enable or disable profiling while running GDB, to profile a
1409 session or a set of commands. In addition there is a new configure switch,
1410 "--enable-profiling", which will cause GDB to be compiled with profiling
1411 data, for more informative profiling results.
1413 * Default MI syntax changed to "mi2".
1415 The default MI (machine interface) syntax, enabled by the command line
1416 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1417 "mi1", can be enabled by specifying the option "-i=mi1".
1419 Support for the original "mi0" syntax (included in GDB 5.0) has been
1422 Fix for gdb/192: removed extraneous space when displaying frame level.
1423 Fix for gdb/672: update changelist is now output in mi list format.
1424 Fix for gdb/702: a -var-assign that updates the value now shows up
1425 in a subsequent -var-update.
1427 * New native configurations.
1429 FreeBSD/amd64 x86_64-*-freebsd*
1431 * Multi-arched targets.
1433 HP/PA HPUX11 hppa*-*-hpux*
1434 Renesas M32R/D w/simulator m32r-*-elf*
1436 * OBSOLETE configurations and files
1438 Configurations that have been declared obsolete in this release have
1439 been commented out. Unless there is activity to revive these
1440 configurations, the next release of GDB will have their sources
1441 permanently REMOVED.
1443 Z8000 simulator z8k-zilog-none or z8ksim
1444 Matsushita MN10200 w/simulator mn10200-*-*
1445 H8/500 simulator h8500-hitachi-hms or h8500hms
1446 HP/PA running BSD hppa*-*-bsd*
1447 HP/PA running OSF/1 hppa*-*-osf*
1448 HP/PA Pro target hppa*-*-pro*
1449 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1450 Sequent family i[3456]86-sequent-sysv4*
1451 i[3456]86-sequent-sysv*
1452 i[3456]86-sequent-bsd*
1453 Tsqware Sparclet sparclet-*-*
1454 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1456 * REMOVED configurations and files
1459 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1460 IBM AIX PS/2 i[3456]86-*-aix
1461 i386 running Mach 3.0 i[3456]86-*-mach3*
1462 i386 running Mach i[3456]86-*-mach*
1463 i386 running OSF/1 i[3456]86-*osf1mk*
1464 HP/Apollo 68k Family m68*-apollo*-sysv*,
1466 m68*-hp-bsd*, m68*-hp-hpux*
1467 Argonaut Risc Chip (ARC) arc-*-*
1468 Mitsubishi D30V d30v-*-*
1469 Fujitsu FR30 fr30-*-elf*
1470 OS/9000 i[34]86-*-os9k
1471 I960 with MON960 i960-*-coff
1473 * MIPS $fp behavior changed
1475 The convenience variable $fp, for the MIPS, now consistently returns
1476 the address of the current frame's base. Previously, depending on the
1477 context, $fp could refer to either $sp or the current frame's base
1478 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1479 The GNU Source-Level Debugger''.
1481 *** Changes in GDB 5.3:
1483 * GNU/Linux shared library multi-threaded performance improved.
1485 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1486 `/proc', in preference to `ptrace' for memory reads. This may result
1487 in an improvement in the start-up time of multi-threaded, shared
1488 library applications when run under GDB. One GDB user writes: ``loads
1489 shared libs like mad''.
1491 * ``gdbserver'' now supports multi-threaded applications on some targets
1493 Support for debugging multi-threaded applications which use
1494 the GNU/Linux LinuxThreads package has been added for
1495 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1496 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1498 * GDB now supports C/C++ preprocessor macros.
1500 GDB now expands preprocessor macro invocations in C/C++ expressions,
1501 and provides various commands for showing macro definitions and how
1504 The new command `macro expand EXPRESSION' expands any macro
1505 invocations in expression, and shows the result.
1507 The new command `show macro MACRO-NAME' shows the definition of the
1508 macro named MACRO-NAME, and where it was defined.
1510 Most compilers don't include information about macros in the debugging
1511 information by default. In GCC 3.1, for example, you need to compile
1512 your program with the options `-gdwarf-2 -g3'. If the macro
1513 information is present in the executable, GDB will read it.
1515 * Multi-arched targets.
1517 DEC Alpha (partial) alpha*-*-*
1518 DEC VAX (partial) vax-*-*
1520 National Semiconductor NS32000 (partial) ns32k-*-*
1521 Motorola 68000 (partial) m68k-*-*
1522 Motorola MCORE mcore-*-*
1526 Fujitsu FRV architecture added by Red Hat frv*-*-*
1529 * New native configurations
1531 Alpha NetBSD alpha*-*-netbsd*
1532 SH NetBSD sh*-*-netbsdelf*
1533 MIPS NetBSD mips*-*-netbsd*
1534 UltraSPARC NetBSD sparc64-*-netbsd*
1536 * OBSOLETE configurations and files
1538 Configurations that have been declared obsolete in this release have
1539 been commented out. Unless there is activity to revive these
1540 configurations, the next release of GDB will have their sources
1541 permanently REMOVED.
1543 Mitsubishi D30V d30v-*-*
1544 OS/9000 i[34]86-*-os9k
1545 IBM AIX PS/2 i[3456]86-*-aix
1546 Fujitsu FR30 fr30-*-elf*
1547 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1548 Argonaut Risc Chip (ARC) arc-*-*
1549 i386 running Mach 3.0 i[3456]86-*-mach3*
1550 i386 running Mach i[3456]86-*-mach*
1551 i386 running OSF/1 i[3456]86-*osf1mk*
1552 HP/Apollo 68k Family m68*-apollo*-sysv*,
1554 m68*-hp-bsd*, m68*-hp-hpux*
1555 I960 with MON960 i960-*-coff
1557 * OBSOLETE languages
1559 CHILL, a Pascal like language used by telecommunications companies.
1561 * REMOVED configurations and files
1563 AMD 29k family via UDI a29k-amd-udi, udi29k
1564 A29K VxWorks a29k-*-vxworks
1565 AMD 29000 embedded, using EBMON a29k-none-none
1566 AMD 29000 embedded with COFF a29k-none-coff
1567 AMD 29000 embedded with a.out a29k-none-aout
1569 testsuite/gdb.hp/gdb.threads-hp/ directory
1571 * New command "set max-user-call-depth <nnn>"
1573 This command allows the user to limit the call depth of user-defined
1574 commands. The default is 1024.
1576 * Changes in FreeBSD/i386 native debugging.
1578 Support for the "generate-core-file" has been added.
1580 * New commands "dump", "append", and "restore".
1582 These commands allow data to be copied from target memory
1583 to a bfd-format or binary file (dump and append), and back
1584 from a file into memory (restore).
1586 * Improved "next/step" support on multi-processor Alpha Tru64.
1588 The previous single-step mechanism could cause unpredictable problems,
1589 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1590 of a software single-step mechanism prevents this.
1592 *** Changes in GDB 5.2.1:
1600 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1601 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1602 Fix, by Joel Brobecker imported from mainline.
1604 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1605 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1606 Fix, by Fred Fish, imported from mainline.
1608 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1609 Surprisingly enough, it works now.
1610 By Michal Ludvig, imported from mainline.
1612 i386 hardware watchpoint support:
1613 avoid misses on second run for some targets.
1614 By Pierre Muller, imported from mainline.
1616 *** Changes in GDB 5.2:
1618 * New command "set trust-readonly-sections on[off]".
1620 This command is a hint that tells gdb that read-only sections
1621 really are read-only (ie. that their contents will not change).
1622 In this mode, gdb will go to the object file rather than the
1623 target to read memory from read-only sections (such as ".text").
1624 This can be a significant performance improvement on some
1625 (notably embedded) targets.
1627 * New command "generate-core-file" (or "gcore").
1629 This new gdb command allows the user to drop a core file of the child
1630 process state at any time. So far it's been implemented only for
1631 GNU/Linux and Solaris, but should be relatively easily ported to other
1632 hosts. Argument is core file name (defaults to core.<pid>).
1634 * New command line option
1636 GDB now accepts --pid or -p followed by a process id.
1638 * Change in command line behavior -- corefiles vs. process ids.
1640 There is a subtle behavior in the way in which GDB handles
1641 command line arguments. The first non-flag argument is always
1642 a program to debug, but the second non-flag argument may either
1643 be a corefile or a process id. Previously, GDB would attempt to
1644 open the second argument as a corefile, and if that failed, would
1645 issue a superfluous error message and then attempt to attach it as
1646 a process. Now, if the second argument begins with a non-digit,
1647 it will be treated as a corefile. If it begins with a digit,
1648 GDB will attempt to attach it as a process, and if no such process
1649 is found, will then attempt to open it as a corefile.
1651 * Changes in ARM configurations.
1653 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1654 configuration is fully multi-arch.
1656 * New native configurations
1658 ARM NetBSD arm*-*-netbsd*
1659 x86 OpenBSD i[3456]86-*-openbsd*
1660 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1661 Sparc64 running FreeBSD sparc64-*-freebsd*
1665 Sanyo XStormy16 xstormy16-elf
1667 * OBSOLETE configurations and files
1669 Configurations that have been declared obsolete in this release have
1670 been commented out. Unless there is activity to revive these
1671 configurations, the next release of GDB will have their sources
1672 permanently REMOVED.
1674 AMD 29k family via UDI a29k-amd-udi, udi29k
1675 A29K VxWorks a29k-*-vxworks
1676 AMD 29000 embedded, using EBMON a29k-none-none
1677 AMD 29000 embedded with COFF a29k-none-coff
1678 AMD 29000 embedded with a.out a29k-none-aout
1680 testsuite/gdb.hp/gdb.threads-hp/ directory
1682 * REMOVED configurations and files
1684 TI TMS320C80 tic80-*-*
1686 PowerPC Solaris powerpcle-*-solaris*
1687 PowerPC Windows NT powerpcle-*-cygwin32
1688 PowerPC Netware powerpc-*-netware*
1689 Harris/CXUX m88k m88*-harris-cxux*
1690 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1691 ns32k-utek-sysv* ns32k-utek-*
1692 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1693 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1694 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1695 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1696 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1698 * Changes to command line processing
1700 The new `--args' feature can be used to specify command-line arguments
1701 for the inferior from gdb's command line.
1703 * Changes to key bindings
1705 There is a new `operate-and-get-next' function bound to `C-o'.
1707 *** Changes in GDB 5.1.1
1709 Fix compile problem on DJGPP.
1711 Fix a problem with floating-point registers on the i386 being
1714 Fix to stop GDB crashing on .debug_str debug info.
1716 Numerous documentation fixes.
1718 Numerous testsuite fixes.
1720 *** Changes in GDB 5.1:
1722 * New native configurations
1724 Alpha FreeBSD alpha*-*-freebsd*
1725 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1726 MIPS GNU/Linux mips*-*-linux*
1727 MIPS SGI Irix 6.x mips*-sgi-irix6*
1728 ia64 AIX ia64-*-aix*
1729 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1733 Motorola 68HC11 and 68HC12 m68hc11-elf
1735 UltraSparc running GNU/Linux sparc64-*-linux*
1737 * OBSOLETE configurations and files
1739 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1740 Harris/CXUX m88k m88*-harris-cxux*
1741 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1742 ns32k-utek-sysv* ns32k-utek-*
1743 TI TMS320C80 tic80-*-*
1745 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1746 PowerPC Solaris powerpcle-*-solaris*
1747 PowerPC Windows NT powerpcle-*-cygwin32
1748 PowerPC Netware powerpc-*-netware*
1749 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1750 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1751 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1752 Apple Macintosh (MPW) host N/A
1754 stuff.c (Program to stuff files into a specially prepared space in kdb)
1755 kdb-start.c (Main loop for the standalone kernel debugger)
1757 Configurations that have been declared obsolete in this release have
1758 been commented out. Unless there is activity to revive these
1759 configurations, the next release of GDB will have their sources
1760 permanently REMOVED.
1762 * REMOVED configurations and files
1764 Altos 3068 m68*-altos-*
1765 Convex c1-*-*, c2-*-*
1767 ARM RISCix arm-*-* (as host)
1771 * GDB has been converted to ISO C.
1773 GDB's source code has been converted to ISO C. In particular, the
1774 sources are fully protoized, and rely on standard headers being
1779 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1781 * The MI enabled by default.
1783 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1784 revised and enabled by default. Packages which use GDB as a debugging
1785 engine behind a UI or another front end are encouraged to switch to
1786 using the GDB/MI interface, instead of the old annotations interface
1787 which is now deprecated.
1789 * Support for debugging Pascal programs.
1791 GDB now includes support for debugging Pascal programs. The following
1792 main features are supported:
1794 - Pascal-specific data types such as sets;
1796 - automatic recognition of Pascal sources based on file-name
1799 - Pascal-style display of data types, variables, and functions;
1801 - a Pascal expression parser.
1803 However, some important features are not yet supported.
1805 - Pascal string operations are not supported at all;
1807 - there are some problems with boolean types;
1809 - Pascal type hexadecimal constants are not supported
1810 because they conflict with the internal variables format;
1812 - support for Pascal objects and classes is not full yet;
1814 - unlike Pascal, GDB is case-sensitive for symbol names.
1816 * Changes in completion.
1818 Commands such as `shell', `run' and `set args', which pass arguments
1819 to inferior programs, now complete on file names, similar to what
1820 users expect at the shell prompt.
1822 Commands which accept locations, such as `disassemble', `print',
1823 `breakpoint', `until', etc. now complete on filenames as well as
1824 program symbols. Thus, if you type "break foob TAB", and the source
1825 files linked into the programs include `foobar.c', that file name will
1826 be one of the candidates for completion. However, file names are not
1827 considered for completion after you typed a colon that delimits a file
1828 name from a name of a function in that file, as in "break foo.c:bar".
1830 `set demangle-style' completes on available demangling styles.
1832 * New platform-independent commands:
1834 It is now possible to define a post-hook for a command as well as a
1835 hook that runs before the command. For more details, see the
1836 documentation of `hookpost' in the GDB manual.
1838 * Changes in GNU/Linux native debugging.
1840 Support for debugging multi-threaded programs has been completely
1841 revised for all platforms except m68k and sparc. You can now debug as
1842 many threads as your system allows you to have.
1844 Attach/detach is supported for multi-threaded programs.
1846 Support for SSE registers was added for x86. This doesn't work for
1847 multi-threaded programs though.
1849 * Changes in MIPS configurations.
1851 Multi-arch support is enabled for all MIPS configurations.
1853 GDB can now be built as native debugger on SGI Irix 6.x systems for
1854 debugging n32 executables. (Debugging 64-bit executables is not yet
1857 * Unified support for hardware watchpoints in all x86 configurations.
1859 Most (if not all) native x86 configurations support hardware-assisted
1860 breakpoints and watchpoints in a unified manner. This support
1861 implements debug register sharing between watchpoints, which allows to
1862 put a virtually infinite number of watchpoints on the same address,
1863 and also supports watching regions up to 16 bytes with several debug
1866 The new maintenance command `maintenance show-debug-regs' toggles
1867 debugging print-outs in functions that insert, remove, and test
1868 watchpoints and hardware breakpoints.
1870 * Changes in the DJGPP native configuration.
1872 New command ``info dos sysinfo'' displays assorted information about
1873 the CPU, OS, memory, and DPMI server.
1875 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1876 display information about segment descriptors stored in GDT, LDT, and
1879 New commands ``info dos pde'' and ``info dos pte'' display entries
1880 from Page Directory and Page Tables (for now works with CWSDPMI only).
1881 New command ``info dos address-pte'' displays the Page Table entry for
1882 a given linear address.
1884 GDB can now pass command lines longer than 126 characters to the
1885 program being debugged (requires an update to the libdbg.a library
1886 which is part of the DJGPP development kit).
1888 DWARF2 debug info is now supported.
1890 It is now possible to `step' and `next' through calls to `longjmp'.
1892 * Changes in documentation.
1894 All GDB documentation was converted to GFDL, the GNU Free
1895 Documentation License.
1897 Tracepoints-related commands are now fully documented in the GDB
1900 TUI, the Text-mode User Interface, is now documented in the manual.
1902 Tracepoints-related commands are now fully documented in the GDB
1905 The "GDB Internals" manual now has an index. It also includes
1906 documentation of `ui_out' functions, GDB coding standards, x86
1907 hardware watchpoints, and memory region attributes.
1909 * GDB's version number moved to ``version.in''
1911 The Makefile variable VERSION has been replaced by the file
1912 ``version.in''. People creating GDB distributions should update the
1913 contents of this file.
1917 GUD support is now a standard part of the EMACS distribution.
1919 *** Changes in GDB 5.0:
1921 * Improved support for debugging FP programs on x86 targets
1923 Unified and much-improved support for debugging floating-point
1924 programs on all x86 targets. In particular, ``info float'' now
1925 displays the FP registers in the same format on all x86 targets, with
1926 greater level of detail.
1928 * Improvements and bugfixes in hardware-assisted watchpoints
1930 It is now possible to watch array elements, struct members, and
1931 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1932 on x86 targets no longer erroneously trigger when the address is
1935 * Improvements in the native DJGPP version of GDB
1937 The distribution now includes all the scripts and auxiliary files
1938 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1939 machines ``out of the box''.
1941 The DJGPP version can now debug programs that use signals. It is
1942 possible to catch signals that happened in the debuggee, deliver
1943 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1944 would kill the program being debugged.) Programs that hook hardware
1945 interrupts (keyboard, timer, etc.) can also be debugged.
1947 It is now possible to debug DJGPP programs that redirect their
1948 standard handles or switch them to raw (as opposed to cooked) mode, or
1949 even close them. The command ``run < foo > bar'' works as expected,
1950 and ``info terminal'' reports useful information about the debuggee's
1951 terminal, including raw/cooked mode, redirection, etc.
1953 The DJGPP version now uses termios functions for console I/O, which
1954 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1957 DOS-style file names with drive letters are now fully supported by
1960 It is now possible to debug DJGPP programs that switch their working
1961 directory. It is also possible to rerun the debuggee any number of
1962 times without restarting GDB; thus, you can use the same setup,
1963 breakpoints, etc. for many debugging sessions.
1965 * New native configurations
1967 ARM GNU/Linux arm*-*-linux*
1968 PowerPC GNU/Linux powerpc-*-linux*
1972 Motorola MCore mcore-*-*
1973 x86 VxWorks i[3456]86-*-vxworks*
1974 PowerPC VxWorks powerpc-*-vxworks*
1975 TI TMS320C80 tic80-*-*
1977 * OBSOLETE configurations
1979 Altos 3068 m68*-altos-*
1980 Convex c1-*-*, c2-*-*
1982 ARM RISCix arm-*-* (as host)
1985 Configurations that have been declared obsolete will be commented out,
1986 but the code will be left in place. If there is no activity to revive
1987 these configurations before the next release of GDB, the sources will
1988 be permanently REMOVED.
1990 * Gould support removed
1992 Support for the Gould PowerNode and NP1 has been removed.
1994 * New features for SVR4
1996 On SVR4 native platforms (such as Solaris), if you attach to a process
1997 without first loading a symbol file, GDB will now attempt to locate and
1998 load symbols from the running process's executable file.
2000 * Many C++ enhancements
2002 C++ support has been greatly improved. Overload resolution now works properly
2003 in almost all cases. RTTI support is on the way.
2005 * Remote targets can connect to a sub-program
2007 A popen(3) style serial-device has been added. This device starts a
2008 sub-process (such as a stand-alone simulator) and then communicates
2009 with that. The sub-program to run is specified using the syntax
2010 ``|<program> <args>'' vis:
2012 (gdb) set remotedebug 1
2013 (gdb) target extended-remote |mn10300-elf-sim program-args
2015 * MIPS 64 remote protocol
2017 A long standing bug in the mips64 remote protocol where by GDB
2018 expected certain 32 bit registers (ex SR) to be transfered as 32
2019 instead of 64 bits has been fixed.
2021 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2022 added to provide backward compatibility with older versions of GDB.
2024 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2026 The command ``set remotebinarydownload'' command has been replaced by
2027 ``set remote X-packet''. Other commands in ``set remote'' family
2028 include ``set remote P-packet''.
2030 * Breakpoint commands accept ranges.
2032 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2033 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2034 ``tracepoint passcount'' also accepts a range of tracepoints.
2036 * ``apropos'' command added.
2038 The ``apropos'' command searches through command names and
2039 documentation strings, printing out matches, making it much easier to
2040 try to find a command that does what you are looking for.
2044 A new machine oriented interface (MI) has been added to GDB. This
2045 interface is designed for debug environments running GDB as a separate
2046 process. This is part of the long term libGDB project. See the
2047 "GDB/MI" chapter of the GDB manual for further information. It can be
2048 enabled by configuring with:
2050 .../configure --enable-gdbmi
2052 *** Changes in GDB-4.18:
2054 * New native configurations
2056 HP-UX 10.20 hppa*-*-hpux10.20
2057 HP-UX 11.x hppa*-*-hpux11.0*
2058 M68K GNU/Linux m68*-*-linux*
2062 Fujitsu FR30 fr30-*-elf*
2063 Intel StrongARM strongarm-*-*
2064 Mitsubishi D30V d30v-*-*
2066 * OBSOLETE configurations
2068 Gould PowerNode, NP1 np1-*-*, pn-*-*
2070 Configurations that have been declared obsolete will be commented out,
2071 but the code will be left in place. If there is no activity to revive
2072 these configurations before the next release of GDB, the sources will
2073 be permanently REMOVED.
2077 As a compatibility experiment, GDB's source files buildsym.h and
2078 buildsym.c have been converted to pure standard C, no longer
2079 containing any K&R compatibility code. We believe that all systems in
2080 use today either come with a standard C compiler, or have a GCC port
2081 available. If this is not true, please report the affected
2082 configuration to bug-gdb@gnu.org immediately. See the README file for
2083 information about getting a standard C compiler if you don't have one
2088 GDB now uses readline 2.2.
2090 * set extension-language
2092 You can now control the mapping between filename extensions and source
2093 languages by using the `set extension-language' command. For instance,
2094 you can ask GDB to treat .c files as C++ by saying
2095 set extension-language .c c++
2096 The command `info extensions' lists all of the recognized extensions
2097 and their associated languages.
2099 * Setting processor type for PowerPC and RS/6000
2101 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2102 you can use the `set processor' command to specify what variant of the
2103 PowerPC family you are debugging. The command
2107 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2108 following PowerPC and RS6000 variants:
2110 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2111 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2113 403GC IBM PowerPC 403GC
2114 505 Motorola PowerPC 505
2115 860 Motorola PowerPC 860 or 850
2116 601 Motorola PowerPC 601
2117 602 Motorola PowerPC 602
2118 603 Motorola/IBM PowerPC 603 or 603e
2119 604 Motorola PowerPC 604 or 604e
2120 750 Motorola/IBM PowerPC 750 or 750
2122 At the moment, this command just tells GDB what to name the
2123 special-purpose processor registers. Since almost all the affected
2124 registers are inaccessible to user-level programs, this command is
2125 only useful for remote debugging in its present form.
2129 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2130 more extensive support for HP-UX. Added features include shared
2131 library support, kernel threads and hardware watchpoints for 11.00,
2132 support for HP's ANSI C and C++ compilers, and a compatibility mode
2133 for xdb and dbx commands.
2137 HP's donation includes the new concept of catchpoints, which is a
2138 generalization of the old catch command. On HP-UX, it is now possible
2139 to catch exec, fork, and vfork, as well as library loading.
2141 This means that the existing catch command has changed; its first
2142 argument now specifies the type of catch to be set up. See the
2143 output of "help catch" for a list of catchpoint types.
2145 * Debugging across forks
2147 On HP-UX, you can choose which process to debug when a fork() happens
2152 HP has donated a curses-based terminal user interface (TUI). To get
2153 it, build with --enable-tui. Although this can be enabled for any
2154 configuration, at present it only works for native HP debugging.
2156 * GDB remote protocol additions
2158 A new protocol packet 'X' that writes binary data is now available.
2159 Default behavior is to try 'X', then drop back to 'M' if the stub
2160 fails to respond. The settable variable `remotebinarydownload'
2161 allows explicit control over the use of 'X'.
2163 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2164 full 64-bit address. The command
2166 set remoteaddresssize 32
2168 can be used to revert to the old behaviour. For existing remote stubs
2169 the change should not be noticed, as the additional address information
2172 In order to assist in debugging stubs, you may use the maintenance
2173 command `packet' to send any text string to the stub. For instance,
2175 maint packet heythere
2177 sends the packet "$heythere#<checksum>". Note that it is very easy to
2178 disrupt a debugging session by sending the wrong packet at the wrong
2181 The compare-sections command allows you to compare section data on the
2182 target to what is in the executable file without uploading or
2183 downloading, by comparing CRC checksums.
2185 * Tracing can collect general expressions
2187 You may now collect general expressions at tracepoints. This requires
2188 further additions to the target-side stub; see tracepoint.c and
2189 doc/agentexpr.texi for further details.
2191 * mask-address variable for Mips
2193 For Mips targets, you may control the zeroing of the upper 32 bits of
2194 a 64-bit address by entering `set mask-address on'. This is mainly
2195 of interest to users of embedded R4xxx and R5xxx processors.
2197 * Higher serial baud rates
2199 GDB's serial code now allows you to specify baud rates 57600, 115200,
2200 230400, and 460800 baud. (Note that your host system may not be able
2201 to achieve all of these rates.)
2205 The i960 configuration now includes an initial implementation of a
2206 builtin simulator, contributed by Jim Wilson.
2209 *** Changes in GDB-4.17:
2211 * New native configurations
2213 Alpha GNU/Linux alpha*-*-linux*
2214 Unixware 2.x i[3456]86-unixware2*
2215 Irix 6.x mips*-sgi-irix6*
2216 PowerPC GNU/Linux powerpc-*-linux*
2217 PowerPC Solaris powerpcle-*-solaris*
2218 Sparc GNU/Linux sparc-*-linux*
2219 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2223 Argonaut Risc Chip (ARC) arc-*-*
2224 Hitachi H8/300S h8300*-*-*
2225 Matsushita MN10200 w/simulator mn10200-*-*
2226 Matsushita MN10300 w/simulator mn10300-*-*
2227 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2228 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2229 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2230 Mitsubishi D10V w/simulator d10v-*-*
2231 Mitsubishi M32R/D w/simulator m32r-*-elf*
2232 Tsqware Sparclet sparclet-*-*
2233 NEC V850 w/simulator v850-*-*
2235 * New debugging protocols
2237 ARM with RDI protocol arm*-*-*
2238 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2239 DDB and LSI variants of PMON protocol mips*-*-*
2240 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2241 PowerPC with SDS protocol powerpc{,le}-*-eabi
2242 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2246 All configurations can now understand and use the DWARF 2 debugging
2247 format. The choice is automatic, if the symbol file contains DWARF 2
2252 GDB now includes basic Java language support. This support is
2253 only useful with Java compilers that produce native machine code.
2255 * solib-absolute-prefix and solib-search-path
2257 For SunOS and SVR4 shared libraries, you may now set the prefix for
2258 loading absolute shared library symbol files, and the search path for
2259 locating non-absolute shared library symbol files.
2261 * Live range splitting
2263 GDB can now effectively debug code for which GCC has performed live
2264 range splitting as part of its optimization. See gdb/doc/LRS for
2265 more details on the expected format of the stabs information.
2269 GDB's support for the GNU Hurd, including thread debugging, has been
2270 updated to work with current versions of the Hurd.
2274 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2275 instruction set. ARM GDB automatically detects when Thumb
2276 instructions are in use, and adjusts disassembly and backtracing
2281 GDB's MIPS target configurations now handle the MIP16 16-bit
2286 GDB now includes support for overlays; if an executable has been
2287 linked such that multiple sections are based at the same address, GDB
2288 will decide which section to use for symbolic info. You can choose to
2289 control the decision manually, using overlay commands, or implement
2290 additional target-side support and use "overlay load-target" to bring
2291 in the overlay mapping. Do "help overlay" for more detail.
2295 The command "info symbol <address>" displays information about
2296 the symbol at the specified address.
2300 The standard remote protocol now includes an extension that allows
2301 asynchronous collection and display of trace data. This requires
2302 extensive support in the target-side debugging stub. Tracing mode
2303 includes a new interaction mode in GDB and new commands: see the
2304 file tracepoint.c for more details.
2308 Configurations for embedded MIPS now include a simulator contributed
2309 by Cygnus Solutions. The simulator supports the instruction sets
2310 of most MIPS variants.
2314 Sparc configurations may now include the ERC32 simulator contributed
2315 by the European Space Agency. The simulator is not built into
2316 Sparc targets by default; configure with --enable-sim to include it.
2320 For target configurations that may include multiple variants of a
2321 basic architecture (such as MIPS and SH), you may now set the
2322 architecture explicitly. "set arch" sets, "info arch" lists
2323 the possible architectures.
2325 *** Changes in GDB-4.16:
2327 * New native configurations
2329 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2330 M68K NetBSD m68k-*-netbsd*
2331 PowerPC AIX 4.x powerpc-*-aix*
2332 PowerPC MacOS powerpc-*-macos*
2333 PowerPC Windows NT powerpcle-*-cygwin32
2334 RS/6000 AIX 4.x rs6000-*-aix4*
2338 ARM with RDP protocol arm-*-*
2339 I960 with MON960 i960-*-coff
2340 MIPS VxWorks mips*-*-vxworks*
2341 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2342 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2344 Matra Sparclet sparclet-*-*
2348 The powerpc-eabi configuration now includes the PSIM simulator,
2349 contributed by Andrew Cagney, with assistance from Mike Meissner.
2350 PSIM is a very elaborate model of the PowerPC, including not only
2351 basic instruction set execution, but also details of execution unit
2352 performance and I/O hardware. See sim/ppc/README for more details.
2356 GDB now works with Solaris 2.5.
2358 * Windows 95/NT native
2360 GDB will now work as a native debugger on Windows 95 and Windows NT.
2361 To build it from source, you must use the "gnu-win32" environment,
2362 which uses a DLL to emulate enough of Unix to run the GNU tools.
2363 Further information, binaries, and sources are available at
2364 ftp.cygnus.com, under pub/gnu-win32.
2366 * dont-repeat command
2368 If a user-defined command includes the command `dont-repeat', then the
2369 command will not be repeated if the user just types return. This is
2370 useful if the command is time-consuming to run, so that accidental
2371 extra keystrokes don't run the same command many times.
2373 * Send break instead of ^C
2375 The standard remote protocol now includes an option to send a break
2376 rather than a ^C to the target in order to interrupt it. By default,
2377 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2379 * Remote protocol timeout
2381 The standard remote protocol includes a new variable `remotetimeout'
2382 that allows you to set the number of seconds before GDB gives up trying
2383 to read from the target. The default value is 2.
2385 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2387 By default GDB will automatically keep track of objects as they are
2388 loaded and unloaded by the dynamic linker. By using the command `set
2389 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2390 when shared library events occur, thus allowing you to set breakpoints
2391 in shared libraries which are explicitly loaded by the inferior.
2393 Note this feature does not work on hpux8. On hpux9 you must link
2394 /usr/lib/end.o into your program. This feature should work
2395 automatically on hpux10.
2397 * Irix 5.x hardware watchpoint support
2399 Irix 5 configurations now support the use of hardware watchpoints.
2401 * Mips protocol "SYN garbage limit"
2403 When debugging a Mips target using the `target mips' protocol, you
2404 may set the number of characters that GDB will ignore by setting
2405 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2406 every character. The default value is 1050.
2408 * Recording and replaying remote debug sessions
2410 If you set `remotelogfile' to the name of a file, gdb will write to it
2411 a recording of a remote debug session. This recording may then be
2412 replayed back to gdb using "gdbreplay". See gdbserver/README for
2413 details. This is useful when you have a problem with GDB while doing
2414 remote debugging; you can make a recording of the session and send it
2415 to someone else, who can then recreate the problem.
2417 * Speedups for remote debugging
2419 GDB includes speedups for downloading and stepping MIPS systems using
2420 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2421 and more efficient S-record downloading.
2423 * Memory use reductions and statistics collection
2425 GDB now uses less memory and reports statistics about memory usage.
2426 Try the `maint print statistics' command, for example.
2428 *** Changes in GDB-4.15:
2430 * Psymtabs for XCOFF
2432 The symbol reader for AIX GDB now uses partial symbol tables. This
2433 can greatly improve startup time, especially for large executables.
2435 * Remote targets use caching
2437 Remote targets now use a data cache to speed up communication with the
2438 remote side. The data cache could lead to incorrect results because
2439 it doesn't know about volatile variables, thus making it impossible to
2440 debug targets which use memory mapped I/O devices. `set remotecache
2441 off' turns the the data cache off.
2443 * Remote targets may have threads
2445 The standard remote protocol now includes support for multiple threads
2446 in the target system, using new protocol commands 'H' and 'T'. See
2447 gdb/remote.c for details.
2451 If GDB is configured with `--enable-netrom', then it will include
2452 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2453 acts as though it is a bank of ROM on the target board, but you can
2454 write into it over the network. GDB's support consists only of
2455 support for fast loading into the emulated ROM; to debug, you must use
2456 another protocol, such as standard remote protocol. The usual
2457 sequence is something like
2459 target nrom <netrom-hostname>
2461 target remote <netrom-hostname>:1235
2465 GDB now includes support for the Apple Macintosh, as a host only. It
2466 may be run as either an MPW tool or as a standalone application, and
2467 it can debug through the serial port. All the usual GDB commands are
2468 available, but to the target command, you must supply "serial" as the
2469 device type instead of "/dev/ttyXX". See mpw-README in the main
2470 directory for more information on how to build. The MPW configuration
2471 scripts */mpw-config.in support only a few targets, and only the
2472 mips-idt-ecoff target has been tested.
2476 GDB configuration now uses autoconf. This is not user-visible,
2477 but does simplify configuration and building.
2481 GDB now supports hpux10.
2483 *** Changes in GDB-4.14:
2485 * New native configurations
2487 x86 FreeBSD i[345]86-*-freebsd
2488 x86 NetBSD i[345]86-*-netbsd
2489 NS32k NetBSD ns32k-*-netbsd
2490 Sparc NetBSD sparc-*-netbsd
2494 A29K VxWorks a29k-*-vxworks
2495 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2496 CPU32 EST-300 emulator m68*-*-est*
2497 PowerPC ELF powerpc-*-elf
2500 * Alpha OSF/1 support for procfs
2502 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2503 possible to attach to running processes. As the mounting of the /proc
2504 filesystem is optional on the Alpha, GDB automatically determines
2505 the availability of /proc during startup. This can lead to problems
2506 if /proc is unmounted after GDB has been started.
2508 * Arguments to user-defined commands
2510 User commands may accept up to 10 arguments separated by whitespace.
2511 Arguments are accessed within the user command via $arg0..$arg9. A
2514 print $arg0 + $arg1 + $arg2
2516 To execute the command use:
2519 Defines the command "adder" which prints the sum of its three arguments.
2520 Note the arguments are text substitutions, so they may reference variables,
2521 use complex expressions, or even perform inferior function calls.
2523 * New `if' and `while' commands
2525 This makes it possible to write more sophisticated user-defined
2526 commands. Both commands take a single argument, which is the
2527 expression to evaluate, and must be followed by the commands to
2528 execute, one per line, if the expression is nonzero, the list being
2529 terminated by the word `end'. The `if' command list may include an
2530 `else' word, which causes the following commands to be executed only
2531 if the expression is zero.
2533 * Fortran source language mode
2535 GDB now includes partial support for Fortran 77. It will recognize
2536 Fortran programs and can evaluate a subset of Fortran expressions, but
2537 variables and functions may not be handled correctly. GDB will work
2538 with G77, but does not yet know much about symbols emitted by other
2541 * Better HPUX support
2543 Most debugging facilities now work on dynamic executables for HPPAs
2544 running hpux9 or later. You can attach to running dynamically linked
2545 processes, but by default the dynamic libraries will be read-only, so
2546 for instance you won't be able to put breakpoints in them. To change
2547 that behavior do the following before running the program:
2553 This will cause the libraries to be mapped private and read-write.
2554 To revert to the normal behavior, do this:
2560 You cannot set breakpoints or examine data in the library until after
2561 the library is loaded if the function/data symbols do not have
2564 GDB can now also read debug symbols produced by the HP C compiler on
2565 HPPAs (sorry, no C++, Fortran or 68k support).
2567 * Target byte order now dynamically selectable
2569 You can choose which byte order to use with a target system, via the
2570 commands "set endian big" and "set endian little", and you can see the
2571 current setting by using "show endian". You can also give the command
2572 "set endian auto", in which case GDB will use the byte order
2573 associated with the executable. Currently, only embedded MIPS
2574 configurations support dynamic selection of target byte order.
2576 * New DOS host serial code
2578 This version uses DPMI interrupts to handle buffered I/O, so you
2579 no longer need to run asynctsr when debugging boards connected to
2582 *** Changes in GDB-4.13:
2584 * New "complete" command
2586 This lists all the possible completions for the rest of the line, if it
2587 were to be given as a command itself. This is intended for use by emacs.
2589 * Trailing space optional in prompt
2591 "set prompt" no longer adds a space for you after the prompt you set. This
2592 allows you to set a prompt which ends in a space or one that does not.
2594 * Breakpoint hit counts
2596 "info break" now displays a count of the number of times the breakpoint
2597 has been hit. This is especially useful in conjunction with "ignore"; you
2598 can ignore a large number of breakpoint hits, look at the breakpoint info
2599 to see how many times the breakpoint was hit, then run again, ignoring one
2600 less than that number, and this will get you quickly to the last hit of
2603 * Ability to stop printing at NULL character
2605 "set print null-stop" will cause GDB to stop printing the characters of
2606 an array when the first NULL is encountered. This is useful when large
2607 arrays actually contain only short strings.
2609 * Shared library breakpoints
2611 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2612 breakpoints in shared libraries before the executable is run.
2614 * Hardware watchpoints
2616 There is a new hardware breakpoint for the watch command for sparclite
2617 targets. See gdb/sparclite/hw_breakpoint.note.
2619 Hardware watchpoints are also now supported under GNU/Linux.
2623 Annotations have been added. These are for use with graphical interfaces,
2624 and are still experimental. Currently only gdba.el uses these.
2626 * Improved Irix 5 support
2628 GDB now works properly with Irix 5.2.
2630 * Improved HPPA support
2632 GDB now works properly with the latest GCC and GAS.
2634 * New native configurations
2636 Sequent PTX4 i[34]86-sequent-ptx4
2637 HPPA running OSF/1 hppa*-*-osf*
2638 Atari TT running SVR4 m68*-*-sysv4*
2639 RS/6000 LynxOS rs6000-*-lynxos*
2643 OS/9000 i[34]86-*-os9k
2644 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2647 * Hitachi SH7000 and E7000-PC ICE support
2649 There is now support for communicating with the Hitachi E7000-PC ICE.
2650 This is available automatically when GDB is configured for the SH.
2654 As usual, a variety of small fixes and improvements, both generic
2655 and configuration-specific. See the ChangeLog for more detail.
2657 *** Changes in GDB-4.12:
2659 * Irix 5 is now supported
2663 GDB-4.12 on the HPPA has a number of changes which make it unable
2664 to debug the output from the currently released versions of GCC and
2665 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2666 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2667 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2670 *** Changes in GDB-4.11:
2672 * User visible changes:
2676 The "set remotedebug" option is now consistent between the mips remote
2677 target, remote targets using the gdb-specific protocol, UDI (AMD's
2678 debug protocol for the 29k) and the 88k bug monitor. It is now an
2679 integer specifying a debug level (normally 0 or 1, but 2 means more
2680 debugging info for the mips target).
2682 * DEC Alpha native support
2684 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2685 debug info, but GDB works fairly well with the DEC compiler and should
2686 work with a future GCC release. See the README file for a few
2687 Alpha-specific notes.
2689 * Preliminary thread implementation
2691 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2693 * LynxOS native and target support for 386
2695 This release has been hosted on LynxOS 2.2, and also can be configured
2696 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2699 * Improvements in C++ mangling/demangling.
2701 This release has much better g++ debugging, specifically in name
2702 mangling/demangling, virtual function calls, print virtual table,
2703 call methods, ...etc.
2705 *** Changes in GDB-4.10:
2707 * User visible changes:
2709 Remote debugging using the GDB-specific (`target remote') protocol now
2710 supports the `load' command. This is only useful if you have some
2711 other way of getting the stub to the target system, and you can put it
2712 somewhere in memory where it won't get clobbered by the download.
2714 Filename completion now works.
2716 When run under emacs mode, the "info line" command now causes the
2717 arrow to point to the line specified. Also, "info line" prints
2718 addresses in symbolic form (as well as hex).
2720 All vxworks based targets now support a user settable option, called
2721 vxworks-timeout. This option represents the number of seconds gdb
2722 should wait for responses to rpc's. You might want to use this if
2723 your vxworks target is, perhaps, a slow software simulator or happens
2724 to be on the far side of a thin network line.
2728 This release contains support for using a DEC alpha as a GDB host for
2729 cross debugging. Native alpha debugging is not supported yet.
2732 *** Changes in GDB-4.9:
2736 This is the first GDB release which is accompanied by a matching testsuite.
2737 The testsuite requires installation of dejagnu, which should be available
2738 via ftp from most sites that carry GNU software.
2742 'Cfront' style demangling has had its name changed to 'ARM' style, to
2743 emphasize that it was written from the specifications in the C++ Annotated
2744 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2745 disclaimers, it still generated too much confusion with users attempting to
2746 use gdb with AT&T cfront.
2750 GDB now uses a standard remote interface to a simulator library.
2751 So far, the library contains simulators for the Zilog Z8001/2, the
2752 Hitachi H8/300, H8/500 and Super-H.
2754 * New targets supported
2756 H8/300 simulator h8300-hitachi-hms or h8300hms
2757 H8/500 simulator h8500-hitachi-hms or h8500hms
2758 SH simulator sh-hitachi-hms or sh
2759 Z8000 simulator z8k-zilog-none or z8ksim
2760 IDT MIPS board over serial line mips-idt-ecoff
2762 Cross-debugging to GO32 targets is supported. It requires a custom
2763 version of the i386-stub.c module which is integrated with the
2764 GO32 memory extender.
2766 * New remote protocols
2768 MIPS remote debugging protocol.
2770 * New source languages supported
2772 This version includes preliminary support for Chill, a Pascal like language
2773 used by telecommunications companies. Chill support is also being integrated
2774 into the GNU compiler, but we don't know when it will be publically available.
2777 *** Changes in GDB-4.8:
2779 * HP Precision Architecture supported
2781 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2782 version of this support was available as a set of patches from the
2783 University of Utah. GDB does not support debugging of programs
2784 compiled with the HP compiler, because HP will not document their file
2785 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2786 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2788 Many problems in the preliminary version have been fixed.
2790 * Faster and better demangling
2792 We have improved template demangling and fixed numerous bugs in the GNU style
2793 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2794 character types (wchar_t) are now supported. Demangling of each symbol is now
2795 only done once, and is cached when the symbol table for a file is read in.
2796 This results in a small increase in memory usage for C programs, a moderate
2797 increase in memory usage for C++ programs, and a fantastic speedup in
2800 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2801 from the specifications in the Annotated Reference Manual, which AT&T's
2802 compiler does not actually implement.
2804 * G++ multiple inheritance compiler problem
2806 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2807 inheritance lattices was reworked to properly discover ambiguities. We
2808 recently found an example which causes this new algorithm to fail in a
2809 very subtle way, producing bad debug information for those classes.
2810 The file 'gcc.patch' (in this directory) can be applied to gcc to
2811 circumvent the problem. A future GCC release will contain a complete
2814 The previous G++ debug info problem (mentioned below for the gdb-4.7
2815 release) is fixed in gcc version 2.3.2.
2817 * Improved configure script
2819 The `configure' script will now attempt to guess your system type if
2820 you don't supply a host system type. The old scheme of supplying a
2821 host system triplet is preferable over using this. All the magic is
2822 done in the new `config.guess' script. Examine it for details.
2824 We have also brought our configure script much more in line with the FSF's
2825 version. It now supports the --with-xxx options. In particular,
2826 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2827 The resulting GDB will not be able to read arbitrary object file formats --
2828 only the format ``expected'' to be used on the configured target system.
2829 We hope to make this the default in a future release.
2831 * Documentation improvements
2833 There's new internal documentation on how to modify GDB, and how to
2834 produce clean changes to the code. We implore people to read it
2835 before submitting changes.
2837 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2838 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2839 `info' files are also provided. To build `info' files from scratch,
2840 you will need the latest `makeinfo' release, which will be available in
2841 a future texinfo-X.Y release.
2843 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2844 We're not sure exactly which versions have this problem, but it has
2845 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2846 or better. If that isn't possible, there is a patch in
2847 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2848 around this problem.
2852 GDB now supports array constants that can be used in expressions typed in by
2853 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2854 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2857 The new directory `gdb/sparclite' contains a program that demonstrates
2858 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2860 * New native hosts supported
2862 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2863 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2865 * New targets supported
2867 AMD 29k family via UDI a29k-amd-udi or udi29k
2869 * New file formats supported
2871 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2872 HPUX core files, and SCO 3.2v2 core files.
2876 Attaching to processes now works again; thanks for the many bug reports.
2878 We have also stomped on a bunch of core dumps caused by
2879 printf_filtered("%s") problems.
2881 We eliminated a copyright problem on the rpc and ptrace header files
2882 for VxWorks, which was discovered at the last minute during the 4.7
2883 release. You should now be able to build a VxWorks GDB.
2885 You can now interrupt gdb while an attached process is running. This
2886 will cause the attached process to stop, and give control back to GDB.
2888 We fixed problems caused by using too many file descriptors
2889 for reading symbols from object files and libraries. This was
2890 especially a problem for programs that used many (~100) shared
2893 The `step' command now only enters a subroutine if there is line number
2894 information for the subroutine. Otherwise it acts like the `next'
2895 command. Previously, `step' would enter subroutines if there was
2896 any debugging information about the routine. This avoids problems
2897 when using `cc -g1' on MIPS machines.
2899 * Internal improvements
2901 GDB's internal interfaces have been improved to make it easier to support
2902 debugging of multiple languages in the future.
2904 GDB now uses a common structure for symbol information internally.
2905 Minimal symbols (derived from linkage symbols in object files), partial
2906 symbols (from a quick scan of debug information), and full symbols
2907 contain a common subset of information, making it easier to write
2908 shared code that handles any of them.
2910 * New command line options
2912 We now accept --silent as an alias for --quiet.
2916 The memory-mapped-malloc library is now licensed under the GNU Library
2917 General Public License.
2919 *** Changes in GDB-4.7:
2921 * Host/native/target split
2923 GDB has had some major internal surgery to untangle the support for
2924 hosts and remote targets. Now, when you configure GDB for a remote
2925 target, it will no longer load in all of the support for debugging
2926 local programs on the host. When fully completed and tested, this will
2927 ensure that arbitrary host/target combinations are possible.
2929 The primary conceptual shift is to separate the non-portable code in
2930 GDB into three categories. Host specific code is required any time GDB
2931 is compiled on that host, regardless of the target. Target specific
2932 code relates to the peculiarities of the target, but can be compiled on
2933 any host. Native specific code is everything else: it can only be
2934 built when the host and target are the same system. Child process
2935 handling and core file support are two common `native' examples.
2937 GDB's use of /proc for controlling Unix child processes is now cleaner.
2938 It has been split out into a single module under the `target_ops' vector,
2939 plus two native-dependent functions for each system that uses /proc.
2941 * New hosts supported
2943 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2944 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2945 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2947 * New targets supported
2949 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2950 68030 and CPU32 m68030-*-*, m68332-*-*
2952 * New native hosts supported
2954 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2955 (386bsd is not well tested yet)
2956 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2958 * New file formats supported
2960 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2961 supports reading of `a.out.adobe' object files, which are an a.out
2962 format extended with minimal information about multiple sections.
2966 `show copying' is the same as the old `info copying'.
2967 `show warranty' is the same as `info warrantee'.
2968 These were renamed for consistency. The old commands continue to work.
2970 `info handle' is a new alias for `info signals'.
2972 You can now define pre-command hooks, which attach arbitrary command
2973 scripts to any command. The commands in the hook will be executed
2974 prior to the user's command. You can also create a hook which will be
2975 executed whenever the program stops. See gdb.texinfo.
2979 We now deal with Cfront style name mangling, and can even extract type
2980 info from mangled symbols. GDB can automatically figure out which
2981 symbol mangling style your C++ compiler uses.
2983 Calling of methods and virtual functions has been improved as well.
2987 The crash that occured when debugging Sun Ansi-C compiled binaries is
2988 fixed. This was due to mishandling of the extra N_SO stabs output
2991 We also finally got Ultrix 4.2 running in house, and fixed core file
2992 support, with help from a dozen people on the net.
2994 John M. Farrell discovered that the reason that single-stepping was so
2995 slow on all of the Mips based platforms (primarily SGI and DEC) was
2996 that we were trying to demangle and lookup a symbol used for internal
2997 purposes on every instruction that was being stepped through. Changing
2998 the name of that symbol so that it couldn't be mistaken for a C++
2999 mangled symbol sped things up a great deal.
3001 Rich Pixley sped up symbol lookups in general by getting much smarter
3002 about when C++ symbol mangling is necessary. This should make symbol
3003 completion (TAB on the command line) much faster. It's not as fast as
3004 we'd like, but it's significantly faster than gdb-4.6.
3008 A new user controllable variable 'call_scratch_address' can
3009 specify the location of a scratch area to be used when GDB
3010 calls a function in the target. This is necessary because the
3011 usual method of putting the scratch area on the stack does not work
3012 in systems that have separate instruction and data spaces.
3014 We integrated changes to support the 29k UDI (Universal Debugger
3015 Interface), but discovered at the last minute that we didn't have all
3016 of the appropriate copyright paperwork. We are working with AMD to
3017 resolve this, and hope to have it available soon.
3021 We have sped up the remote serial line protocol, especially for targets
3022 with lots of registers. It now supports a new `expedited status' ('T')
3023 message which can be used in place of the existing 'S' status message.
3024 This allows the remote stub to send only the registers that GDB
3025 needs to make a quick decision about single-stepping or conditional
3026 breakpoints, eliminating the need to fetch the entire register set for
3027 each instruction being stepped through.
3029 The GDB remote serial protocol now implements a write-through cache for
3030 registers, only re-reading the registers if the target has run.
3032 There is also a new remote serial stub for SPARC processors. You can
3033 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3034 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3035 processor with a serial port.
3039 Configure.in files have become much easier to read and modify. A new
3040 `table driven' format makes it more obvious what configurations are
3041 supported, and what files each one uses.
3045 There is a new opcodes library which will eventually contain all of the
3046 disassembly routines and opcode tables. At present, it only contains
3047 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3048 disassembler (binutils/objdump) to share these routines.
3050 The libiberty library is now copylefted under the GNU Library General
3051 Public License. This allows more liberal use, and was done so libg++
3052 can use it. This makes no difference to GDB, since the Library License
3053 grants all the rights from the General Public License.
3057 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3058 reference to the stabs symbol info used by the debugger. It is (as far
3059 as we know) the only published document on this fascinating topic. We
3060 encourage you to read it, compare it to the stabs information on your
3061 system, and send improvements on the document in general (to
3062 bug-gdb@prep.ai.mit.edu).
3064 And, of course, many bugs have been fixed.
3067 *** Changes in GDB-4.6:
3069 * Better support for C++ function names
3071 GDB now accepts as input the "demangled form" of C++ overloaded function
3072 names and member function names, and can do command completion on such names
3073 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3074 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3075 Make use of command completion, it is your friend.
3077 GDB also now accepts a variety of C++ mangled symbol formats. They are
3078 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3079 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3080 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3081 for the list of formats.
3083 * G++ symbol mangling problem
3085 Recent versions of gcc have a bug in how they emit debugging information for
3086 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3087 directory) can be applied to gcc to fix the problem. Alternatively, if you
3088 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3089 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3090 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3093 * New 'maintenance' command
3095 All of the commands related to hacking GDB internals have been moved out of
3096 the main command set, and now live behind the 'maintenance' command. This
3097 can also be abbreviated as 'mt'. The following changes were made:
3099 dump-me -> maintenance dump-me
3100 info all-breakpoints -> maintenance info breakpoints
3101 printmsyms -> maintenance print msyms
3102 printobjfiles -> maintenance print objfiles
3103 printpsyms -> maintenance print psymbols
3104 printsyms -> maintenance print symbols
3106 The following commands are new:
3108 maintenance demangle Call internal GDB demangler routine to
3109 demangle a C++ link name and prints the result.
3110 maintenance print type Print a type chain for a given symbol
3112 * Change to .gdbinit file processing
3114 We now read the $HOME/.gdbinit file before processing the argv arguments
3115 (e.g. reading symbol files or core files). This allows global parameters to
3116 be set, which will apply during the symbol reading. The ./.gdbinit is still
3117 read after argv processing.
3119 * New hosts supported
3121 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3123 GNU/Linux support i386-unknown-linux or linux
3125 We are also including code to support the HP/PA running BSD and HPUX. This
3126 is almost guaranteed not to work, as we didn't have time to test or build it
3127 for this release. We are including it so that the more adventurous (or
3128 masochistic) of you can play with it. We also had major problems with the
3129 fact that the compiler that we got from HP doesn't support the -g option.
3132 * New targets supported
3134 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3136 * More smarts about finding #include files
3138 GDB now remembers the compilation directory for all include files, and for
3139 all files from which C is generated (like yacc and lex sources). This
3140 greatly improves GDB's ability to find yacc/lex sources, and include files,
3141 especially if you are debugging your program from a directory different from
3142 the one that contains your sources.
3144 We also fixed a bug which caused difficulty with listing and setting
3145 breakpoints in include files which contain C code. (In the past, you had to
3146 try twice in order to list an include file that you hadn't looked at before.)
3148 * Interesting infernals change
3150 GDB now deals with arbitrary numbers of sections, where the symbols for each
3151 section must be relocated relative to that section's landing place in the
3152 target's address space. This work was needed to support ELF with embedded
3153 stabs used by Solaris-2.0.
3155 * Bug fixes (of course!)
3157 There have been loads of fixes for the following things:
3158 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3159 i960, stabs, DOS(GO32), procfs, etc...
3161 See the ChangeLog for details.
3163 *** Changes in GDB-4.5:
3165 * New machines supported (host and target)
3167 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3169 SGI Irix-4.x mips-sgi-irix4 or iris4
3171 * New malloc package
3173 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3174 Mmalloc is capable of handling mutiple heaps of memory. It is also
3175 capable of saving a heap to a file, and then mapping it back in later.
3176 This can be used to greatly speedup the startup of GDB by using a
3177 pre-parsed symbol table which lives in a mmalloc managed heap. For
3178 more details, please read mmalloc/mmalloc.texi.
3182 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3183 'help info proc' for details.
3185 * MIPS ecoff symbol table format
3187 The code that reads MIPS symbol table format is now supported on all hosts.
3188 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3191 * File name changes for MS-DOS
3193 Many files in the config directories have been renamed to make it easier to
3194 support GDB on MS-DOSe systems (which have very restrictive file name
3195 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3196 environment) is close to working but has some remaining problems. Note
3197 that debugging of DOS programs is not supported, due to limitations
3198 in the ``operating system'', but it can be used to host cross-debugging.
3200 * Cross byte order fixes
3202 Many fixes have been made to support cross debugging of Sparc and MIPS
3203 targets from hosts whose byte order differs.
3205 * New -mapped and -readnow options
3207 If memory-mapped files are available on your system through the 'mmap'
3208 system call, you can use the -mapped option on the `file' or
3209 `symbol-file' commands to cause GDB to write the symbols from your
3210 program into a reusable file. If the program you are debugging is
3211 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3212 Future GDB debugging sessions will notice the presence of this file,
3213 and will quickly map in symbol information from it, rather than reading
3214 the symbol table from the executable program. Using the '-mapped'
3215 option in a GDB `file' or `symbol-file' command has the same effect as
3216 starting GDB with the '-mapped' command-line option.
3218 You can cause GDB to read the entire symbol table immediately by using
3219 the '-readnow' option with any of the commands that load symbol table
3220 information (or on the GDB command line). This makes the command
3221 slower, but makes future operations faster.
3223 The -mapped and -readnow options are typically combined in order to
3224 build a `fred.syms' file that contains complete symbol information.
3225 A simple GDB invocation to do nothing but build a `.syms' file for future
3228 gdb -batch -nx -mapped -readnow programname
3230 The `.syms' file is specific to the host machine on which GDB is run.
3231 It holds an exact image of GDB's internal symbol table. It cannot be
3232 shared across multiple host platforms.
3234 * longjmp() handling
3236 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3237 siglongjmp() without losing control. This feature has not yet been ported to
3238 all systems. It currently works on many 386 platforms, all MIPS-based
3239 platforms (SGI, DECstation, etc), and Sun3/4.
3243 Preliminary work has been put in to support the new Solaris OS from Sun. At
3244 this time, it can control and debug processes, but it is not capable of
3249 As always, many many bug fixes. The major areas were with g++, and mipsread.
3250 People using the MIPS-based platforms should experience fewer mysterious
3251 crashes and trashed symbol tables.
3253 *** Changes in GDB-4.4:
3255 * New machines supported (host and target)
3257 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3259 BSD Reno on Vax vax-dec-bsd
3260 Ultrix on Vax vax-dec-ultrix
3262 * New machines supported (target)
3264 AMD 29000 embedded, using EBMON a29k-none-none
3268 GDB continues to improve its handling of C++. `References' work better.
3269 The demangler has also been improved, and now deals with symbols mangled as
3270 per the Annotated C++ Reference Guide.
3272 GDB also now handles `stabs' symbol information embedded in MIPS
3273 `ecoff' symbol tables. Since the ecoff format was not easily
3274 extensible to handle new languages such as C++, this appeared to be a
3275 good way to put C++ debugging info into MIPS binaries. This option
3276 will be supported in the GNU C compiler, version 2, when it is
3279 * New features for SVR4
3281 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3282 shared libraries. Debugging dynamically linked programs should present
3283 only minor differences from debugging statically linked programs.
3285 The `info proc' command will print out information about any process
3286 on an SVR4 system (including the one you are debugging). At the moment,
3287 it prints the address mappings of the process.
3289 If you bring up GDB on another SVR4 system, please send mail to
3290 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3292 * Better dynamic linking support in SunOS
3294 Reading symbols from shared libraries which contain debugging symbols
3295 now works properly. However, there remain issues such as automatic
3296 skipping of `transfer vector' code during function calls, which
3297 make it harder to debug code in a shared library, than to debug the
3298 same code linked statically.
3302 GDB is now using the latest `getopt' routines from the FSF. This
3303 version accepts the -- prefix for options with long names. GDB will
3304 continue to accept the old forms (-option and +option) as well.
3305 Various single letter abbreviations for options have been explicity
3306 added to the option table so that they won't get overshadowed in the
3307 future by other options that begin with the same letter.
3311 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3312 Many assorted bugs have been handled. Many more remain to be handled.
3313 See the various ChangeLog files (primarily in gdb and bfd) for details.
3316 *** Changes in GDB-4.3:
3318 * New machines supported (host and target)
3320 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3321 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3322 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3324 * Almost SCO Unix support
3326 We had hoped to support:
3327 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3328 (except for core file support), but we discovered very late in the release
3329 that it has problems with process groups that render gdb unusable. Sorry
3330 about that. I encourage people to fix it and post the fixes.
3332 * Preliminary ELF and DWARF support
3334 GDB can read ELF object files on System V Release 4, and can handle
3335 debugging records for C, in DWARF format, in ELF files. This support
3336 is preliminary. If you bring up GDB on another SVR4 system, please
3337 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3342 GDB now uses the latest `readline' library. One user-visible change
3343 is that two tabs will list possible command completions, which previously
3344 required typing M-? (meta-question mark, or ESC ?).
3348 The `stepi' bug that many of you noticed has been squashed.
3349 Many bugs in C++ have been handled. Many more remain to be handled.
3350 See the various ChangeLog files (primarily in gdb and bfd) for details.
3352 * State of the MIPS world (in case you wondered):
3354 GDB can understand the symbol tables emitted by the compilers
3355 supplied by most vendors of MIPS-based machines, including DEC. These
3356 symbol tables are in a format that essentially nobody else uses.
3358 Some versions of gcc come with an assembler post-processor called
3359 mips-tfile. This program is required if you want to do source-level
3360 debugging of gcc-compiled programs. I believe FSF does not ship
3361 mips-tfile with gcc version 1, but it will eventually come with gcc
3364 Debugging of g++ output remains a problem. g++ version 1.xx does not
3365 really support it at all. (If you're lucky, you should be able to get
3366 line numbers and stack traces to work, but no parameters or local
3367 variables.) With some work it should be possible to improve the
3370 When gcc version 2 is released, you will have somewhat better luck.
3371 However, even then you will get confusing results for inheritance and
3374 We will eventually provide full debugging of g++ output on
3375 DECstations. This will probably involve some kind of stabs-in-ecoff
3376 encapulation, but the details have not been worked out yet.
3379 *** Changes in GDB-4.2:
3381 * Improved configuration
3383 Only one copy of `configure' exists now, and it is not self-modifying.
3384 Porting BFD is simpler.
3388 The `step' and `next' commands now only stop at the first instruction
3389 of a source line. This prevents the multiple stops that used to occur
3390 in switch statements, for-loops, etc. `Step' continues to stop if a
3391 function that has debugging information is called within the line.
3395 Lots of small bugs fixed. More remain.
3397 * New host supported (not target)
3399 Intel 386 PC clone running Mach i386-none-mach
3402 *** Changes in GDB-4.1:
3404 * Multiple source language support
3406 GDB now has internal scaffolding to handle several source languages.
3407 It determines the type of each source file from its filename extension,
3408 and will switch expression parsing and number formatting to match the
3409 language of the function in the currently selected stack frame.
3410 You can also specifically set the language to be used, with
3411 `set language c' or `set language modula-2'.
3415 GDB now has preliminary support for the GNU Modula-2 compiler,
3416 currently under development at the State University of New York at
3417 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3418 continue through the fall of 1991 and into 1992.
3420 Other Modula-2 compilers are currently not supported, and attempting to
3421 debug programs compiled with them will likely result in an error as the
3422 symbol table is read. Feel free to work on it, though!
3424 There are hooks in GDB for strict type checking and range checking,
3425 in the `Modula-2 philosophy', but they do not currently work.
3429 GDB can now write to executable and core files (e.g. patch
3430 a variable's value). You must turn this switch on, specify
3431 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3432 by assigning a new value to a variable. Modifications take
3435 * Automatic SunOS shared library reading
3437 When you run your program, GDB automatically determines where its
3438 shared libraries (if any) have been loaded, and reads their symbols.
3439 The `share' command is no longer needed. This also works when
3440 examining core files.
3444 You can specify the number of lines that the `list' command shows.
3447 * New machines supported (host and target)
3449 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3450 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3451 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3453 * New hosts supported (not targets)
3455 IBM RT/PC: romp-ibm-aix or rtpc
3457 * New targets supported (not hosts)
3459 AMD 29000 embedded with COFF a29k-none-coff
3460 AMD 29000 embedded with a.out a29k-none-aout
3461 Ultracomputer remote kernel debug a29k-nyu-kern
3463 * New remote interfaces
3469 *** Changes in GDB-4.0:
3473 Wide output is wrapped at good places to make the output more readable.
3475 Gdb now supports cross-debugging from a host machine of one type to a
3476 target machine of another type. Communication with the target system
3477 is over serial lines. The ``target'' command handles connecting to the
3478 remote system; the ``load'' command will download a program into the
3479 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3480 also supports debugging of realtime processes running under VxWorks,
3481 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3482 stub on the target system.
3484 New CPUs supported include the AMD 29000 and Intel 960.
3486 GDB now reads object files and symbol tables via a ``binary file''
3487 library, which allows a single copy of GDB to debug programs of multiple
3488 object file types such as a.out and coff.
3490 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3491 refcard.dvi and refcard.ps are available to format it).
3494 * Control-Variable user interface simplified
3496 All variables that control the operation of the debugger can be set
3497 by the ``set'' command, and displayed by the ``show'' command.
3499 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3500 ``Show prompt'' produces the response:
3501 Gdb's prompt is new-gdb=>.
3503 What follows are the NEW set commands. The command ``help set'' will
3504 print a complete list of old and new set commands. ``help set FOO''
3505 will give a longer description of the variable FOO. ``show'' will show
3506 all of the variable descriptions and their current settings.
3508 confirm on/off: Enables warning questions for operations that are
3509 hard to recover from, e.g. rerunning the program while
3510 it is already running. Default is ON.
3512 editing on/off: Enables EMACS style command line editing
3513 of input. Previous lines can be recalled with
3514 control-P, the current line can be edited with control-B,
3515 you can search for commands with control-R, etc.
3518 history filename NAME: NAME is where the gdb command history
3519 will be stored. The default is .gdb_history,
3520 or the value of the environment variable
3523 history size N: The size, in commands, of the command history. The
3524 default is 256, or the value of the environment variable
3527 history save on/off: If this value is set to ON, the history file will
3528 be saved after exiting gdb. If set to OFF, the
3529 file will not be saved. The default is OFF.
3531 history expansion on/off: If this value is set to ON, then csh-like
3532 history expansion will be performed on
3533 command line input. The default is OFF.
3535 radix N: Sets the default radix for input and output. It can be set
3536 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3537 in the current radix, so "set radix 10" is always a no-op.
3539 height N: This integer value is the number of lines on a page. Default
3540 is 24, the current `stty rows'' setting, or the ``li#''
3541 setting from the termcap entry matching the environment
3544 width N: This integer value is the number of characters on a line.
3545 Default is 80, the current `stty cols'' setting, or the ``co#''
3546 setting from the termcap entry matching the environment
3549 Note: ``set screensize'' is obsolete. Use ``set height'' and
3550 ``set width'' instead.
3552 print address on/off: Print memory addresses in various command displays,
3553 such as stack traces and structure values. Gdb looks
3554 more ``symbolic'' if you turn this off; it looks more
3555 ``machine level'' with it on. Default is ON.
3557 print array on/off: Prettyprint arrays. New convenient format! Default
3560 print demangle on/off: Print C++ symbols in "source" form if on,
3563 print asm-demangle on/off: Same, for assembler level printouts
3566 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3569 * Support for Epoch Environment.
3571 The epoch environment is a version of Emacs v18 with windowing. One
3572 new command, ``inspect'', is identical to ``print'', except that if you
3573 are running in the epoch environment, the value is printed in its own
3577 * Support for Shared Libraries
3579 GDB can now debug programs and core files that use SunOS shared libraries.
3580 Symbols from a shared library cannot be referenced
3581 before the shared library has been linked with the program (this
3582 happens after you type ``run'' and before the function main() is entered).
3583 At any time after this linking (including when examining core files
3584 from dynamically linked programs), gdb reads the symbols from each
3585 shared library when you type the ``sharedlibrary'' command.
3586 It can be abbreviated ``share''.
3588 sharedlibrary REGEXP: Load shared object library symbols for files
3589 matching a unix regular expression. No argument
3590 indicates to load symbols for all shared libraries.
3592 info sharedlibrary: Status of loaded shared libraries.
3597 A watchpoint stops execution of a program whenever the value of an
3598 expression changes. Checking for this slows down execution
3599 tremendously whenever you are in the scope of the expression, but is
3600 quite useful for catching tough ``bit-spreader'' or pointer misuse
3601 problems. Some machines such as the 386 have hardware for doing this
3602 more quickly, and future versions of gdb will use this hardware.
3604 watch EXP: Set a watchpoint (breakpoint) for an expression.
3606 info watchpoints: Information about your watchpoints.
3608 delete N: Deletes watchpoint number N (same as breakpoints).
3609 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3610 enable N: Re-enables watchpoint number N (same as breakpoints).
3613 * C++ multiple inheritance
3615 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3618 * C++ exception handling
3620 Gdb now supports limited C++ exception handling. Besides the existing
3621 ability to breakpoint on an exception handler, gdb can breakpoint on
3622 the raising of an exception (before the stack is peeled back to the
3625 catch FOO: If there is a FOO exception handler in the dynamic scope,
3626 set a breakpoint to catch exceptions which may be raised there.
3627 Multiple exceptions (``catch foo bar baz'') may be caught.
3629 info catch: Lists all exceptions which may be caught in the
3630 current stack frame.
3633 * Minor command changes
3635 The command ``call func (arg, arg, ...)'' now acts like the print
3636 command, except it does not print or save a value if the function's result
3637 is void. This is similar to dbx usage.
3639 The ``up'' and ``down'' commands now always print the frame they end up
3640 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3641 frames without printing.
3643 * New directory command
3645 'dir' now adds directories to the FRONT of the source search path.
3646 The path starts off empty. Source files that contain debug information
3647 about the directory in which they were compiled can be found even
3648 with an empty path; Sun CC and GCC include this information. If GDB can't
3649 find your source file in the current directory, type "dir .".
3651 * Configuring GDB for compilation
3653 For normal use, type ``./configure host''. See README or gdb.texinfo
3656 GDB now handles cross debugging. If you are remotely debugging between
3657 two different machines, type ``./configure host -target=targ''.
3658 Host is the machine where GDB will run; targ is the machine
3659 where the program that you are debugging will run.