1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.0
8 Xilinx MicroBlaze microblaze-*-*
12 Xilinx MicroBlaze microblaze
14 * Multi-program debugging.
16 GDB now has support for multi-program (a.k.a. multi-executable or
17 multi-exec) debugging. This allows for debugging multiple inferiors
18 simultaneously each running a different program under the same GDB
19 session. See "Debugging Multiple Inferiors and Programs" in the
20 manual for more information. This implied some user visible changes
21 in the multi-inferior support. For example, "info inferiors" now
22 lists inferiors that are not running yet or that have exited
23 already. See also "New commands" and "New options" below.
25 * New commands (for set/show, see "New options" below)
27 add-inferior [-copies <N>] [-exec <FILENAME>]
30 clone-inferior [-copies <N>] [ID]
31 Make a new inferior ready to execute the same program another
37 maint info program-spaces
38 List the program spaces loaded into GDB.
40 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
41 show remote interrupt-sequence
42 Allow the user to select one of ^C, a BREAK signal or BREAK-g
43 as the sequence to the remote target in order to interrupt the execution.
44 Ctrl-C is a default. Some system prefers BREAK which is high level of
45 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
46 Magic SysRq g. It is BREAK signal and character 'g'.
48 set remote interrupt-on-connect [on | off]
49 show remote interrupt-on-connect
50 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
51 remote target when gdb connects to it. This is needed when you debug
54 set remotebreak [on | off]
56 Deprecated. Use "set/show remote interrupt-sequence" instead.
60 set follow-exec-mode new|same
62 Control whether GDB reuses the same inferior across an exec call or
63 creates a new one. This is useful to be able to restart the old
64 executable after the inferior having done an exec call.
66 *** Changes in GDB 7.0
68 * GDB now has an interface for JIT compilation. Applications that
69 dynamically generate code can create symbol files in memory and register
70 them with GDB. For users, the feature should work transparently, and
71 for JIT developers, the interface is documented in the GDB manual in the
72 "JIT Compilation Interface" chapter.
74 * Tracepoints may now be conditional. The syntax is as for
75 breakpoints; either an "if" clause appended to the "trace" command,
76 or the "condition" command is available. GDB sends the condition to
77 the target for evaluation using the same bytecode format as is used
78 for tracepoint actions.
80 * "disassemble" command with a /r modifier, print the raw instructions
81 in hex as well as in symbolic form."
83 * Process record and replay
85 In a architecture environment that supports ``process record and
86 replay'', ``process record and replay'' target can record a log of
87 the process execution, and replay it with both forward and reverse
90 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
91 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
92 set execution-direction {forward|reverse}, for targets that support
95 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
96 feature is available with a native GDB running on kernel version
99 * GDB now has support for multi-byte and wide character sets on the
100 target. Strings whose character type is wchar_t, char16_t, or
101 char32_t are now correctly printed. GDB supports wide- and unicode-
102 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
103 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
104 `printf'. This feature requires iconv to work properly; if your
105 system does not have a working iconv, GDB can use GNU libiconv. See
106 the installation instructions for more information.
108 * GDB now supports automatic retrieval of shared library files from
109 remote targets. To use this feature, specify a system root that begins
110 with the `remote:' prefix, either via the `set sysroot' command or via
111 the `--with-sysroot' configure-time option.
113 * "info sharedlibrary" now takes an optional regex of libraries to show,
114 and it now reports if a shared library has no debugging information.
116 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
117 now complete on file names.
119 * When completing in expressions, gdb will attempt to limit
120 completions to allowable structure or union fields, where appropriate.
121 For instance, consider:
123 # struct example { int f1; double f2; };
124 # struct example variable;
127 If the user types TAB at the end of this command line, the available
128 completions will be "f1" and "f2".
130 * Inlined functions are now supported. They show up in backtraces, and
131 the "step", "next", and "finish" commands handle them automatically.
133 * GDB now supports the token-splicing (##) and stringification (#)
134 operators when expanding macros. It also supports variable-arity
137 * GDB now supports inspecting extra signal information, exported by
138 the new $_siginfo convenience variable. The feature is currently
139 implemented on linux ARM, i386 and amd64.
141 * GDB can now display the VFP floating point registers and NEON vector
142 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
143 can provide these registers (requires Linux 2.6.30 or later). Remote
144 and simulator targets may also provide them.
149 Search memory for a sequence of bytes.
152 Turn off `+'/`-' protocol acknowledgments to permit more efficient
153 operation over reliable transport links. Use of this packet is
154 controlled by the `set remote noack-packet' command.
157 Kill the process with the specified process ID. Use this in preference
158 to `k' when multiprocess protocol extensions are supported.
161 Obtains additional operating system information
165 Read or write additional signal information.
167 * Removed remote protocol undocumented extension
169 An undocumented extension to the remote protocol's `S' stop reply
170 packet that permited the stub to pass a process id was removed.
171 Remote servers should use the `T' stop reply packet instead.
173 * The "disassemble" command now supports an optional /m modifier to print mixed
176 * GDB now supports multiple function calling conventions according to the
177 DWARF-2 DW_AT_calling_convention function attribute.
179 * The SH target utilizes the aforementioned change to distinguish between gcc
180 and Renesas calling convention. It also adds the new CLI commands
181 `set/show sh calling-convention'.
183 * GDB can now read compressed debug sections, as produced by GNU gold
184 with the --compress-debug-sections=zlib flag.
186 * 64-bit core files are now supported on AIX.
188 * Thread switching is now supported on Tru64.
190 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
191 which will be allocated using malloc later in program execution.
193 * The qXfer:libraries:read remote procotol packet now allows passing a
194 list of section offsets.
196 * On GNU/Linux, GDB can now attach to stopped processes. Several race
197 conditions handling signals delivered during attach or thread creation
198 have also been fixed.
200 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
201 From the user's standpoint, all unqualified instances of True and False
202 are treated as the standard definitions, regardless of context.
204 * GDB now parses C++ symbol and type names more flexibly. For
207 template<typename T> class C { };
210 GDB will now correctly handle all of:
212 ptype C<char const *>
214 ptype C<const char *>
217 * New features in the GDB remote stub, gdbserver
219 - The "--wrapper" command-line argument tells gdbserver to use a
220 wrapper program to launch programs for debugging.
222 - On PowerPC and S/390 targets, it is now possible to use a single
223 gdbserver executable to debug both 32-bit and 64-bit programs.
224 (This requires gdbserver itself to be built as a 64-bit executable.)
226 - gdbserver uses the new noack protocol mode for TCP connections to
227 reduce communications latency, if also supported and enabled in GDB.
229 - Support for the sparc64-linux-gnu target is now included in
232 - The amd64-linux build of gdbserver now supports debugging both
233 32-bit and 64-bit programs.
235 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
236 now support hardware watchpoints, and will use them automatically
241 GDB now has support for scripting using Python. Whether this is
242 available is determined at configure time.
244 New GDB commands can now be written in Python.
246 * Ada tasking support
248 Ada tasks can now be inspected in GDB. The following commands have
252 Print the list of Ada tasks.
254 Print detailed information about task number N.
256 Print the task number of the current task.
258 Switch the context of debugging to task number N.
260 * Support for user-defined prefixed commands. The "define" command can
261 add new commands to existing prefixes, e.g. "target".
263 * Multi-inferior, multi-process debugging.
265 GDB now has generalized support for multi-inferior debugging. See
266 "Debugging Multiple Inferiors" in the manual for more information.
267 Although availability still depends on target support, the command
268 set is more uniform now. The GNU/Linux specific multi-forks support
269 has been migrated to this new framework. This implied some user
270 visible changes; see "New commands" and also "Removed commands"
273 * Target descriptions can now describe the target OS ABI. See the
274 "Target Description Format" section in the user manual for more
277 * Target descriptions can now describe "compatible" architectures
278 to indicate that the target can execute applications for a different
279 architecture in addition to those for the main target architecture.
280 See the "Target Description Format" section in the user manual for
283 * Multi-architecture debugging.
285 GDB now includes general supports for debugging applications on
286 hybrid systems that use more than one single processor architecture
287 at the same time. Each such hybrid architecture still requires
288 specific support to be added. The only hybrid architecture supported
289 in this version of GDB is the Cell Broadband Engine.
291 * GDB now supports integrated debugging of Cell/B.E. applications that
292 use both the PPU and SPU architectures. To enable support for hybrid
293 Cell/B.E. debugging, you need to configure GDB to support both the
294 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
295 --enable-targets configure option.
297 * Non-stop mode debugging.
299 For some targets, GDB now supports an optional mode of operation in
300 which you can examine stopped threads while other threads continue
301 to execute freely. This is referred to as non-stop mode, with the
302 old mode referred to as all-stop mode. See the "Non-Stop Mode"
303 section in the user manual for more information.
305 To be able to support remote non-stop debugging, a remote stub needs
306 to implement the non-stop mode remote protocol extensions, as
307 described in the "Remote Non-Stop" section of the user manual. The
308 GDB remote stub, gdbserver, has been adjusted to support these
309 extensions on linux targets.
311 * New commands (for set/show, see "New options" below)
313 catch syscall [NAME(S) | NUMBER(S)]
314 Catch system calls. Arguments, which should be names of system
315 calls or their numbers, mean catch only those syscalls. Without
316 arguments, every syscall will be caught. When the inferior issues
317 any of the specified syscalls, GDB will stop and announce the system
318 call, both when it is called and when its call returns. This
319 feature is currently available with a native GDB running on the
320 Linux Kernel, under the following architectures: x86, x86_64,
321 PowerPC and PowerPC64.
323 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
325 Search memory for a sequence of bytes.
327 maint set python print-stack
328 maint show python print-stack
329 Show a stack trace when an error is encountered in a Python script.
332 Invoke CODE by passing it to the Python interpreter.
337 These allow macros to be defined, undefined, and listed
341 Show operating system information about processes.
344 List the inferiors currently under GDB's control.
347 Switch focus to inferior number NUM.
350 Detach from inferior number NUM.
353 Kill inferior number NUM.
358 show spu stop-on-load
359 Control whether to stop for new SPE threads during Cell/B.E. debugging.
361 set spu auto-flush-cache
362 show spu auto-flush-cache
363 Control whether to automatically flush the software-managed cache
364 during Cell/B.E. debugging.
366 set sh calling-convention
367 show sh calling-convention
368 Control the calling convention used when calling SH target functions.
372 Control display of timestamps with GDB debugging output.
374 set disassemble-next-line
375 show disassemble-next-line
376 Control display of disassembled source lines or instructions when
379 set remote noack-packet
380 show remote noack-packet
381 Set/show the use of remote protocol QStartNoAckMode packet. See above
382 under "New remote packets."
384 set remote query-attached-packet
385 show remote query-attached-packet
386 Control use of remote protocol `qAttached' (query-attached) packet.
388 set remote read-siginfo-object
389 show remote read-siginfo-object
390 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
393 set remote write-siginfo-object
394 show remote write-siginfo-object
395 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
398 set remote reverse-continue
399 show remote reverse-continue
400 Control use of remote protocol 'bc' (reverse-continue) packet.
402 set remote reverse-step
403 show remote reverse-step
404 Control use of remote protocol 'bs' (reverse-step) packet.
406 set displaced-stepping
407 show displaced-stepping
408 Control displaced stepping mode. Displaced stepping is a way to
409 single-step over breakpoints without removing them from the debuggee.
410 Also known as "out-of-line single-stepping".
414 Control display of debugging info for displaced stepping.
416 maint set internal-error
417 maint show internal-error
418 Control what GDB does when an internal error is detected.
420 maint set internal-warning
421 maint show internal-warning
422 Control what GDB does when an internal warning is detected.
427 Use a wrapper program to launch programs for debugging.
429 set multiple-symbols (all|ask|cancel)
430 show multiple-symbols
431 The value of this variable can be changed to adjust the debugger behavior
432 when an expression or a breakpoint location contains an ambiguous symbol
433 name (an overloaded function name, for instance).
435 set breakpoint always-inserted
436 show breakpoint always-inserted
437 Keep breakpoints always inserted in the target, as opposed to inserting
438 them when resuming the target, and removing them when the target stops.
439 This option can improve debugger performance on slow remote targets.
441 set arm fallback-mode (arm|thumb|auto)
442 show arm fallback-mode
443 set arm force-mode (arm|thumb|auto)
445 These commands control how ARM GDB determines whether instructions
446 are ARM or Thumb. The default for both settings is auto, which uses
447 the current CPSR value for instructions without symbols; previous
448 versions of GDB behaved as if "set arm fallback-mode arm".
450 set disable-randomization
451 show disable-randomization
452 Standalone programs run with the virtual address space randomization enabled
453 by default on some platforms. This option keeps the addresses stable across
454 multiple debugging sessions.
458 Control whether other threads are stopped or not when some thread hits
463 Requests that asynchronous execution is enabled in the target, if available.
464 In this case, it's possible to resume target in the background, and interact
465 with GDB while the target is running. "show target-async" displays the
466 current state of asynchronous execution of the target.
468 set target-wide-charset
469 show target-wide-charset
470 The target-wide-charset is the name of the character set that GDB
471 uses when printing characters whose type is wchar_t.
473 set tcp auto-retry (on|off)
475 set tcp connect-timeout
476 show tcp connect-timeout
477 These commands allow GDB to retry failed TCP connections to a remote stub
478 with a specified timeout period; this is useful if the stub is launched
479 in parallel with GDB but may not be ready to accept connections immediately.
481 set libthread-db-search-path
482 show libthread-db-search-path
483 Control list of directories which GDB will search for appropriate
486 set schedule-multiple (on|off)
487 show schedule-multiple
488 Allow GDB to resume all threads of all processes or only threads of
493 Use more aggressive caching for accesses to the stack. This improves
494 performance of remote debugging (particularly backtraces) without
495 affecting correctness.
497 set interactive-mode (on|off|auto)
498 show interactive-mode
499 Control whether GDB runs in interactive mode (on) or not (off).
500 When in interactive mode, GDB waits for the user to answer all
501 queries. Otherwise, GDB does not wait and assumes the default
502 answer. When set to auto (the default), GDB determines which
503 mode to use based on the stdin settings.
508 For program forks, this is replaced by the new more generic `info
509 inferiors' command. To list checkpoints, you can still use the
510 `info checkpoints' command, which was an alias for the `info forks'
514 Replaced by the new `inferior' command. To switch between
515 checkpoints, you can still use the `restart' command, which was an
516 alias for the `fork' command.
519 This is removed, since some targets don't have a notion of
520 processes. To switch between processes, you can still use the
521 `inferior' command using GDB's own inferior number.
524 For program forks, this is replaced by the new more generic `kill
525 inferior' command. To delete a checkpoint, you can still use the
526 `delete checkpoint' command, which was an alias for the `delete
530 For program forks, this is replaced by the new more generic `detach
531 inferior' command. To detach a checkpoint, you can still use the
532 `detach checkpoint' command, which was an alias for the `detach
535 * New native configurations
537 x86/x86_64 Darwin i[34567]86-*-darwin*
539 x86_64 MinGW x86_64-*-mingw*
543 Lattice Mico32 lm32-*
544 x86 DICOS i[34567]86-*-dicos*
545 x86_64 DICOS x86_64-*-dicos*
548 * The GDB remote stub, gdbserver, now supports x86 Windows CE
549 (mingw32ce) debugging.
555 These commands were actually not implemented on any target.
557 *** Changes in GDB 6.8
559 * New native configurations
561 NetBSD/hppa hppa*-*netbsd*
562 Xtensa GNU/Linux xtensa*-*-linux*
566 NetBSD/hppa hppa*-*-netbsd*
567 Xtensa GNU/Lunux xtensa*-*-linux*
569 * Change in command line behavior -- corefiles vs. process ids.
571 When the '-p NUMBER' or '--pid NUMBER' options are used, and
572 attaching to process NUMBER fails, GDB no longer attempts to open a
573 core file named NUMBER. Attaching to a program using the -c option
574 is no longer supported. Instead, use the '-p' or '--pid' options.
576 * GDB can now be built as a native debugger for debugging Windows x86
577 (mingw32) Portable Executable (PE) programs.
579 * Pending breakpoints no longer change their number when their address
582 * GDB now supports breakpoints with multiple locations,
583 including breakpoints on C++ constructors, inside C++ templates,
584 and in inlined functions.
586 * GDB's ability to debug optimized code has been improved. GDB more
587 accurately identifies function bodies and lexical blocks that occupy
588 more than one contiguous range of addresses.
590 * Target descriptions can now describe registers for PowerPC.
592 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
593 registers on PowerPC targets.
595 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
596 targets even when the libthread_db library is not available.
598 * The GDB remote stub, gdbserver, now supports the new file transfer
599 commands (remote put, remote get, and remote delete).
601 * The GDB remote stub, gdbserver, now supports run and attach in
602 extended-remote mode.
604 * hppa*64*-*-hpux11* target broken
605 The debugger is unable to start a program and fails with the following
606 error: "Error trying to get information about dynamic linker".
607 The gdb-6.7 release is also affected.
609 * GDB now supports the --enable-targets= configure option to allow
610 building a single GDB executable that supports multiple remote
611 target architectures.
613 * GDB now supports debugging C and C++ programs which use the
614 Decimal Floating Point extension. In addition, the PowerPC target
615 now has a set of pseudo-registers to inspect decimal float values
616 stored in two consecutive float registers.
618 * The -break-insert MI command can optionally create pending
621 * Improved support for debugging Ada
622 Many improvements to the Ada language support have been made. These
624 - Better support for Ada2005 interface types
625 - Improved handling of arrays and slices in general
626 - Better support for Taft-amendment types
627 - The '{type} ADDRESS' expression is now allowed on the left hand-side
629 - Improved command completion in Ada
632 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
637 set print frame-arguments (all|scalars|none)
638 show print frame-arguments
639 The value of this variable can be changed to control which argument
640 values should be printed by the debugger when displaying a frame.
645 Transfer files to and from a remote target, and delete remote files.
652 Transfer files to and from a remote target, and delete remote files.
661 Open, close, read, write, and delete files on the remote system.
664 Attach to an existing process on the remote system, in extended-remote
668 Run a new process on the remote system, in extended-remote mode.
670 *** Changes in GDB 6.7
672 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
673 bfd, libiberty and opcodes, as revealed by static analysis donated by
674 Coverity, Inc. (http://scan.coverity.com).
676 * When looking up multiply-defined global symbols, GDB will now prefer the
677 symbol definition in the current shared library if it was built using the
678 -Bsymbolic linker option.
680 * When the Text User Interface (TUI) is not configured, GDB will now
681 recognize the -tui command-line option and print a message that the TUI
684 * The GDB remote stub, gdbserver, now has lower overhead for high
685 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
687 * GDB for MIPS targets now autodetects whether a remote target provides
688 32-bit or 64-bit register values.
690 * Support for C++ member pointers has been improved.
692 * GDB now understands XML target descriptions, which specify the
693 target's overall architecture. GDB can read a description from
694 a local file or over the remote serial protocol.
696 * Vectors of single-byte data use a new integer type which is not
697 automatically displayed as character or string data.
699 * The /s format now works with the print command. It displays
700 arrays of single-byte integers and pointers to single-byte integers
703 * Target descriptions can now describe target-specific registers,
704 for architectures which have implemented the support (currently
705 only ARM, M68K, and MIPS).
707 * GDB and the GDB remote stub, gdbserver, now support the XScale
710 * The GDB remote stub, gdbserver, has been updated to support
711 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
712 has been rewritten to use the standard GDB remote protocol.
714 * GDB can now step into C++ functions which are called through thunks.
716 * GDB for the Cell/B.E. SPU now supports overlay debugging.
718 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
719 layout. It also supports a TextSeg= and DataSeg= response when only
720 segment base addresses (rather than offsets) are available.
722 * The /i format now outputs any trailing branch delay slot instructions
723 immediately following the last instruction within the count specified.
725 * The GDB remote protocol "T" stop reply packet now supports a
726 "library" response. Combined with the new "qXfer:libraries:read"
727 packet, this response allows GDB to debug shared libraries on targets
728 where the operating system manages the list of loaded libraries (e.g.
729 Windows and SymbianOS).
731 * The GDB remote stub, gdbserver, now supports dynamic link libraries
732 (DLLs) on Windows and Windows CE targets.
734 * GDB now supports a faster verification that a .debug file matches its binary
735 according to its build-id signature, if the signature is present.
741 Enable or disable hardware flow control (RTS/CTS) on the serial port
742 when debugging using remote targets.
744 set mem inaccessible-by-default
745 show mem inaccessible-by-default
746 If the target supplies a memory map, for instance via the remote
747 protocol's "qXfer:memory-map:read" packet, setting this variable
748 prevents GDB from accessing memory outside the memory map. This
749 is useful for targets with memory mapped registers or which react
750 badly to accesses of unmapped address space.
752 set breakpoint auto-hw
753 show breakpoint auto-hw
754 If the target supplies a memory map, for instance via the remote
755 protocol's "qXfer:memory-map:read" packet, setting this variable
756 lets GDB use hardware breakpoints automatically for memory regions
757 where it can not use software breakpoints. This covers both the
758 "break" command and internal breakpoints used for other commands
759 including "next" and "finish".
762 catch exception unhandled
763 Stop the program execution when Ada exceptions are raised.
766 Stop the program execution when an Ada assertion failed.
770 Set an alternate system root for target files. This is a more
771 general version of "set solib-absolute-prefix", which is now
772 an alias to "set sysroot".
775 Provide extended SPU facility status information. This set of
776 commands is available only when debugging the Cell/B.E. SPU
779 * New native configurations
781 OpenBSD/sh sh*-*openbsd*
786 Use the specified local file as an XML target description, and do
787 not query the target for its built-in description.
791 OpenBSD/sh sh*-*-openbsd*
792 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
793 Toshiba Media Processor mep-elf
798 Ignore the specified signals; pass them directly to the debugged program
799 without stopping other threads or reporting them to GDB.
802 Read an XML target description from the target, which describes its
807 Read or write contents of an spufs file on the target system. These
808 packets are available only on the Cell/B.E. SPU architecture.
810 qXfer:libraries:read:
811 Report the loaded shared libraries. Combined with new "T" packet
812 response, this packet allows GDB to debug shared libraries on
813 targets where the operating system manages the list of loaded
814 libraries (e.g. Windows and SymbianOS).
818 Support for these obsolete configurations has been removed.
827 i[34567]86-*-netware*
828 i[34567]86-*-sco3.2v5*
829 i[34567]86-*-sco3.2v4*
831 i[34567]86-*-sysv4.2*
834 i[34567]86-*-unixware2*
835 i[34567]86-*-unixware*
844 * Other removed features
851 Various m68k-only ROM monitors.
858 Various Renesas ROM monitors and debugging interfaces for SH and
863 Support for a Macraigor serial interface to on-chip debugging.
864 GDB does not directly support the newer parallel or USB
869 A debug information format. The predecessor to DWARF 2 and
870 DWARF 3, which are still supported.
872 Support for the HP aCC compiler on HP-UX/PA-RISC
874 SOM-encapsulated symbolic debugging information, automatic
875 invocation of pxdb, and the aCC custom C++ ABI. This does not
876 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
877 with aCC can still be debugged on an assembly level.
881 A MIPS-specific format used to describe stack frame layout
882 in debugging information.
886 GDB could work with an older version of Guile to debug
887 the interpreter and Scheme programs running in it.
889 set mips stack-arg-size
890 set mips saved-gpreg-size
892 Use "set mips abi" to control parameter passing for MIPS.
894 *** Changes in GDB 6.6
899 Cell Broadband Engine SPU spu-elf
901 * GDB can now be configured as a cross-debugger targeting native Windows
902 (mingw32) or Cygwin. It can communicate with a remote debugging stub
903 running on a Windows system over TCP/IP to debug Windows programs.
905 * The GDB remote stub, gdbserver, has been updated to support Windows and
906 Cygwin debugging. Both single-threaded and multi-threaded programs are
909 * The "set trust-readonly-sections" command works again. This command was
910 broken in GDB 6.3, 6.4, and 6.5.
912 * The "load" command now supports writing to flash memory, if the remote
913 stub provides the required support.
915 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
916 longer requires symbolic debug information (e.g. DWARF-2).
921 unset substitute-path
923 Manage a list of substitution rules that GDB uses to rewrite the name
924 of the directories where the sources are located. This can be useful
925 for instance when the sources were moved to a different location
926 between compilation and debugging.
930 Print each CLI command as it is executed. Each command is prefixed with
931 a number of `+' symbols representing the nesting depth.
932 The source command now has a `-v' option to enable the same feature.
936 The ARM Demon monitor support (RDP protocol, "target rdp").
938 Kernel Object Display, an embedded debugging feature which only worked with
939 an obsolete version of Cisco IOS.
941 The 'set download-write-size' and 'show download-write-size' commands.
946 Tell a stub about GDB client features, and request remote target features.
947 The first feature implemented is PacketSize, which allows the target to
948 specify the size of packets it can handle - to minimize the number of
949 packets required and improve performance when connected to a remote
953 Fetch an OS auxilliary vector from the remote stub. This packet is a
954 more efficient replacement for qPart:auxv:read.
956 qXfer:memory-map:read:
957 Fetch a memory map from the remote stub, including information about
958 RAM, ROM, and flash memory devices.
963 Erase and program a flash memory device.
965 * Removed remote packets
968 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
969 used it, and only gdbserver implemented it.
971 *** Changes in GDB 6.5
975 Renesas M32C/M16C m32c-elf
977 Morpho Technologies ms1 ms1-elf
981 init-if-undefined Initialize a convenience variable, but
982 only if it doesn't already have a value.
984 The following commands are presently only implemented for native GNU/Linux:
986 checkpoint Save a snapshot of the program state.
988 restart <n> Return the program state to a
989 previously saved state.
991 info checkpoints List currently saved checkpoints.
993 delete-checkpoint <n> Delete a previously saved checkpoint.
995 set|show detach-on-fork Tell gdb whether to detach from a newly
996 forked process, or to keep debugging it.
998 info forks List forks of the user program that
999 are available to be debugged.
1001 fork <n> Switch to debugging one of several
1002 forks of the user program that are
1003 available to be debugged.
1005 delete-fork <n> Delete a fork from the list of forks
1006 that are available to be debugged (and
1007 kill the forked process).
1009 detach-fork <n> Delete a fork from the list of forks
1010 that are available to be debugged (and
1011 allow the process to continue).
1015 Morpho Technologies ms2 ms1-elf
1017 * Improved Windows host support
1019 GDB now builds as a cross debugger hosted on i686-mingw32, including
1020 native console support, and remote communications using either
1021 network sockets or serial ports.
1023 * Improved Modula-2 language support
1025 GDB can now print most types in the Modula-2 syntax. This includes:
1026 basic types, set types, record types, enumerated types, range types,
1027 pointer types and ARRAY types. Procedure var parameters are correctly
1028 printed and hexadecimal addresses and character constants are also
1029 written in the Modula-2 syntax. Best results can be obtained by using
1030 GNU Modula-2 together with the -gdwarf-2 command line option.
1034 The ARM rdi-share module.
1036 The Netware NLM debug server.
1038 *** Changes in GDB 6.4
1040 * New native configurations
1042 OpenBSD/arm arm*-*-openbsd*
1043 OpenBSD/mips64 mips64-*-openbsd*
1047 Morpho Technologies ms1 ms1-elf
1049 * New command line options
1051 --batch-silent As for --batch, but totally silent.
1052 --return-child-result The debugger will exist with the same value
1053 the child (debugged) program exited with.
1054 --eval-command COMMAND, -ex COMMAND
1055 Execute a single GDB CLI command. This may be
1056 specified multiple times and in conjunction
1057 with the --command (-x) option.
1059 * Deprecated commands removed
1061 The following commands, that were deprecated in 2000, have been
1065 set|show arm disassembly-flavor set|show arm disassembler
1066 othernames set arm disassembler
1067 set|show remotedebug set|show debug remote
1068 set|show archdebug set|show debug arch
1069 set|show eventdebug set|show debug event
1072 * New BSD user-level threads support
1074 It is now possible to debug programs using the user-level threads
1075 library on OpenBSD and FreeBSD. Currently supported (target)
1078 FreeBSD/amd64 x86_64-*-freebsd*
1079 FreeBSD/i386 i386-*-freebsd*
1080 OpenBSD/i386 i386-*-openbsd*
1082 Note that the new kernel threads libraries introduced in FreeBSD 5.x
1083 are not yet supported.
1085 * New support for Matsushita MN10300 w/sim added
1086 (Work in progress). mn10300-elf.
1088 * REMOVED configurations and files
1090 VxWorks and the XDR protocol *-*-vxworks
1091 Motorola MCORE mcore-*-*
1092 National Semiconductor NS32000 ns32k-*-*
1094 * New "set print array-indexes" command
1096 After turning this setting "on", GDB prints the index of each element
1097 when displaying arrays. The default is "off" to preserve the previous
1100 * VAX floating point support
1102 GDB now supports the not-quite-ieee VAX F and D floating point formats.
1104 * User-defined command support
1106 In addition to using $arg0..$arg9 for argument passing, it is now possible
1107 to use $argc to determine now many arguments have been passed. See the
1108 section on user-defined commands in the user manual for more information.
1110 *** Changes in GDB 6.3:
1112 * New command line option
1114 GDB now accepts -l followed by a number to set the timeout for remote
1117 * GDB works with GCC -feliminate-dwarf2-dups
1119 GDB now supports a more compact representation of DWARF-2 debug
1120 information using DW_FORM_ref_addr references. These are produced
1121 by GCC with the option -feliminate-dwarf2-dups and also by some
1122 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
1123 to use -feliminate-dwarf2-dups.
1125 * Internationalization
1127 When supported by the host system, GDB will be built with
1128 internationalization (libintl). The task of marking up the sources is
1129 continued, we're looking forward to our first translation.
1133 Initial support for debugging programs compiled with the GNAT
1134 implementation of the Ada programming language has been integrated
1135 into GDB. In this release, support is limited to expression evaluation.
1137 * New native configurations
1139 GNU/Linux/m32r m32r-*-linux-gnu
1143 GDB's remote protocol now includes support for the 'p' packet. This
1144 packet is used to fetch individual registers from a remote inferior.
1146 * END-OF-LIFE registers[] compatibility module
1148 GDB's internal register infrastructure has been completely rewritten.
1149 The new infrastructure making possible the implementation of key new
1150 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
1153 GDB 6.3 will be the last release to include the the registers[]
1154 compatibility module that allowed out-of-date configurations to
1155 continue to work. This change directly impacts the following
1165 powerpc bdm protocol
1167 Unless there is activity to revive these configurations, they will be
1168 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
1170 * OBSOLETE configurations and files
1172 Configurations that have been declared obsolete in this release have
1173 been commented out. Unless there is activity to revive these
1174 configurations, the next release of GDB will have their sources
1175 permanently REMOVED.
1184 *** Changes in GDB 6.2.1:
1186 * MIPS `break main; run' gave an heuristic-fence-post warning
1188 When attempting to run even a simple program, a warning about
1189 heuristic-fence-post being hit would be reported. This problem has
1192 * MIPS IRIX 'long double' crashed GDB
1194 When examining a long double variable, GDB would get a segmentation
1195 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
1196 IRIX long double values).
1200 A bug in the VAX stack code was causing problems with the "next"
1201 command. This problem has been fixed.
1203 *** Changes in GDB 6.2:
1205 * Fix for ``many threads''
1207 On GNU/Linux systems that use the NPTL threads library, a program
1208 rapidly creating and deleting threads would confuse GDB leading to the
1211 ptrace: No such process.
1212 thread_db_get_info: cannot get thread info: generic error
1214 This problem has been fixed.
1216 * "-async" and "-noasync" options removed.
1218 Support for the broken "-noasync" option has been removed (it caused
1221 * New ``start'' command.
1223 This command runs the program until the begining of the main procedure.
1225 * New BSD Kernel Data Access Library (libkvm) interface
1227 Using ``target kvm'' it is now possible to debug kernel core dumps and
1228 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
1229 platforms. Currently supported (native-only) configurations are:
1231 FreeBSD/amd64 x86_64-*-freebsd*
1232 FreeBSD/i386 i?86-*-freebsd*
1233 NetBSD/i386 i?86-*-netbsd*
1234 NetBSD/m68k m68*-*-netbsd*
1235 NetBSD/sparc sparc-*-netbsd*
1236 OpenBSD/amd64 x86_64-*-openbsd*
1237 OpenBSD/i386 i?86-*-openbsd*
1238 OpenBSD/m68k m68*-openbsd*
1239 OpenBSD/sparc sparc-*-openbsd*
1241 * Signal trampoline code overhauled
1243 Many generic problems with GDB's signal handling code have been fixed.
1244 These include: backtraces through non-contiguous stacks; recognition
1245 of sa_sigaction signal trampolines; backtrace from a NULL pointer
1246 call; backtrace through a signal trampoline; step into and out of
1247 signal handlers; and single-stepping in the signal trampoline.
1249 Please note that kernel bugs are a limiting factor here. These
1250 features have been shown to work on an s390 GNU/Linux system that
1251 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
1253 * Cygwin support for DWARF 2 added.
1255 * New native configurations
1257 GNU/Linux/hppa hppa*-*-linux*
1258 OpenBSD/hppa hppa*-*-openbsd*
1259 OpenBSD/m68k m68*-*-openbsd*
1260 OpenBSD/m88k m88*-*-openbsd*
1261 OpenBSD/powerpc powerpc-*-openbsd*
1262 NetBSD/vax vax-*-netbsd*
1263 OpenBSD/vax vax-*-openbsd*
1265 * END-OF-LIFE frame compatibility module
1267 GDB's internal frame infrastructure has been completely rewritten.
1268 The new infrastructure making it possible to support key new features
1269 including DWARF 2 Call Frame Information. To aid in the task of
1270 migrating old configurations to this new infrastructure, a
1271 compatibility module, that allowed old configurations to continue to
1272 work, was also included.
1274 GDB 6.2 will be the last release to include this frame compatibility
1275 module. This change directly impacts the following configurations:
1285 Unless there is activity to revive these configurations, they will be
1286 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
1288 * REMOVED configurations and files
1290 Sun 3, running SunOS 3 m68*-*-sunos3*
1291 Sun 3, running SunOS 4 m68*-*-sunos4*
1292 Sun 2, running SunOS 3 m68000-*-sunos3*
1293 Sun 2, running SunOS 4 m68000-*-sunos4*
1294 Motorola 680x0 running LynxOS m68*-*-lynxos*
1295 AT&T 3b1/Unix pc m68*-att-*
1296 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1297 decstation mips-dec-* mips-little-*
1298 riscos mips-*-riscos* mips-*-sysv*
1299 sonymips mips-sony-*
1300 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1302 *** Changes in GDB 6.1.1:
1304 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
1306 The TUI (Text-mode User Interface) is now built as part of a default
1307 GDB configuration. It is enabled by either selecting the TUI with the
1308 command line option "-i=tui" or by running the separate "gdbtui"
1309 program. For more information on the TUI, see the manual "Debugging
1312 * Pending breakpoint support (also included in GDB 6.1)
1314 Support has been added to allow you to specify breakpoints in shared
1315 libraries that have not yet been loaded. If a breakpoint location
1316 cannot be found, and the "breakpoint pending" option is set to auto,
1317 GDB queries you if you wish to make the breakpoint pending on a future
1318 shared-library load. If and when GDB resolves the breakpoint symbol,
1319 the pending breakpoint is removed as one or more regular breakpoints
1322 Pending breakpoints are very useful for GCJ Java debugging.
1324 * Fixed ISO-C build problems
1326 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
1327 non ISO-C code that stopped them being built using a more strict ISO-C
1328 compiler (e.g., IBM's C compiler).
1330 * Fixed build problem on IRIX 5
1332 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
1333 wasn't able to compile compile on an IRIX 5 system.
1335 * Added execute permission to gdb/gdbserver/configure
1337 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
1338 permission. This bug would cause configure to fail on a number of
1339 systems (Solaris, IRIX). Ref: server/519.
1341 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
1343 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
1344 has been updated to use constant array sizes.
1346 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
1348 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
1349 its generated DWARF Call Frame Info. This encoding was causing GDB to
1350 panic, that panic has been fixed. Ref: gdb/1628.
1352 * Fixed a problem when examining parameters in shared library code.
1354 When examining parameters in optimized shared library code generated
1355 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1356 not available''. GDB now correctly displays the variable's value.
1358 *** Changes in GDB 6.1:
1360 * Removed --with-mmalloc
1362 Support for the mmalloc memory manager has been removed, as it
1363 conflicted with the internal gdb byte cache.
1365 * Changes in AMD64 configurations
1367 The AMD64 target now includes the %cs and %ss registers. As a result
1368 the AMD64 remote protocol has changed; this affects the floating-point
1369 and SSE registers. If you rely on those registers for your debugging,
1370 you should upgrade gdbserver on the remote side.
1372 * Revised SPARC target
1374 The SPARC target has been completely revised, incorporating the
1375 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1376 support for LynxOS and SunOS 4 has been dropped. Calling functions
1377 from within GDB on operating systems with a non-executable stack
1378 (Solaris, OpenBSD) now works.
1382 GDB has a new C++ demangler which does a better job on the mangled
1383 names generated by current versions of g++. It also runs faster, so
1384 with this and other changes gdb should now start faster on large C++
1387 * DWARF 2 Location Expressions
1389 GDB support for location expressions has been extended to support function
1390 arguments and frame bases. Older versions of GDB could crash when they
1393 * C++ nested types and namespaces
1395 GDB's support for nested types and namespaces in C++ has been
1396 improved, especially if you use the DWARF 2 debugging format. (This
1397 is the default for recent versions of GCC on most platforms.)
1398 Specifically, if you have a class "Inner" defined within a class or
1399 namespace "Outer", then GDB realizes that the class's name is
1400 "Outer::Inner", not simply "Inner". This should greatly reduce the
1401 frequency of complaints about not finding RTTI symbols. In addition,
1402 if you are stopped at inside of a function defined within a namespace,
1403 GDB modifies its name lookup accordingly.
1405 * New native configurations
1407 NetBSD/amd64 x86_64-*-netbsd*
1408 OpenBSD/amd64 x86_64-*-openbsd*
1409 OpenBSD/alpha alpha*-*-openbsd*
1410 OpenBSD/sparc sparc-*-openbsd*
1411 OpenBSD/sparc64 sparc64-*-openbsd*
1413 * New debugging protocols
1415 M32R with SDI protocol m32r-*-elf*
1417 * "set prompt-escape-char" command deleted.
1419 The command "set prompt-escape-char" has been deleted. This command,
1420 and its very obscure effet on GDB's prompt, was never documented,
1421 tested, nor mentioned in the NEWS file.
1423 * OBSOLETE configurations and files
1425 Configurations that have been declared obsolete in this release have
1426 been commented out. Unless there is activity to revive these
1427 configurations, the next release of GDB will have their sources
1428 permanently REMOVED.
1430 Sun 3, running SunOS 3 m68*-*-sunos3*
1431 Sun 3, running SunOS 4 m68*-*-sunos4*
1432 Sun 2, running SunOS 3 m68000-*-sunos3*
1433 Sun 2, running SunOS 4 m68000-*-sunos4*
1434 Motorola 680x0 running LynxOS m68*-*-lynxos*
1435 AT&T 3b1/Unix pc m68*-att-*
1436 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1437 decstation mips-dec-* mips-little-*
1438 riscos mips-*-riscos* mips-*-sysv*
1439 sonymips mips-sony-*
1440 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1442 * REMOVED configurations and files
1444 SGI Irix-4.x mips-sgi-irix4 or iris4
1445 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1446 Z8000 simulator z8k-zilog-none or z8ksim
1447 Matsushita MN10200 w/simulator mn10200-*-*
1448 H8/500 simulator h8500-hitachi-hms or h8500hms
1449 HP/PA running BSD hppa*-*-bsd*
1450 HP/PA running OSF/1 hppa*-*-osf*
1451 HP/PA Pro target hppa*-*-pro*
1452 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1453 386BSD i[3456]86-*-bsd*
1454 Sequent family i[3456]86-sequent-sysv4*
1455 i[3456]86-sequent-sysv*
1456 i[3456]86-sequent-bsd*
1457 SPARC running LynxOS sparc-*-lynxos*
1458 SPARC running SunOS 4 sparc-*-sunos4*
1459 Tsqware Sparclet sparclet-*-*
1460 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1462 *** Changes in GDB 6.0:
1466 Support for debugging the Objective-C programming language has been
1467 integrated into GDB.
1469 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1471 DWARF 2's Call Frame Information makes available compiler generated
1472 information that more exactly describes the program's run-time stack.
1473 By using this information, GDB is able to provide more robust stack
1476 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1477 have been updated to use a new backtrace mechanism which includes
1478 DWARF 2 CFI support.
1482 GDB's remote protocol has been extended to include support for hosted
1483 file I/O (where the remote target uses GDB's file system). See GDB's
1484 remote protocol documentation for details.
1486 * All targets using the new architecture framework.
1488 All of GDB's targets have been updated to use the new internal
1489 architecture framework. The way is now open for future GDB releases
1490 to include cross-architecture native debugging support (i386 on amd64,
1493 * GNU/Linux's Thread Local Storage (TLS)
1495 GDB now includes support for for the GNU/Linux implementation of
1496 per-thread variables.
1498 * GNU/Linux's Native POSIX Thread Library (NPTL)
1500 GDB's thread code has been updated to work with either the new
1501 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1503 * Separate debug info.
1505 GDB, in conjunction with BINUTILS, now supports a mechanism for
1506 automatically loading debug information from a separate file. Instead
1507 of shipping full debug and non-debug versions of system libraries,
1508 system integrators can now instead ship just the stripped libraries
1509 and optional debug files.
1511 * DWARF 2 Location Expressions
1513 DWARF 2 Location Expressions allow the compiler to more completely
1514 describe the location of variables (even in optimized code) to the
1517 GDB now includes preliminary support for location expressions (support
1518 for DW_OP_piece is still missing).
1522 A number of long standing bugs that caused GDB to die while starting a
1523 Java application have been fixed. GDB's Java support is now
1524 considered "useable".
1526 * GNU/Linux support for fork, vfork, and exec.
1528 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1529 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1532 * GDB supports logging output to a file
1534 There are two new commands, "set logging" and "show logging", which can be
1535 used to capture GDB's output to a file.
1537 * The meaning of "detach" has changed for gdbserver
1539 The "detach" command will now resume the application, as documented. To
1540 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1543 * d10v, m68hc11 `regs' command deprecated
1545 The `info registers' command has been updated so that it displays the
1546 registers using a format identical to the old `regs' command.
1550 A new command, "maint set profile on/off", has been added. This command can
1551 be used to enable or disable profiling while running GDB, to profile a
1552 session or a set of commands. In addition there is a new configure switch,
1553 "--enable-profiling", which will cause GDB to be compiled with profiling
1554 data, for more informative profiling results.
1556 * Default MI syntax changed to "mi2".
1558 The default MI (machine interface) syntax, enabled by the command line
1559 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1560 "mi1", can be enabled by specifying the option "-i=mi1".
1562 Support for the original "mi0" syntax (included in GDB 5.0) has been
1565 Fix for gdb/192: removed extraneous space when displaying frame level.
1566 Fix for gdb/672: update changelist is now output in mi list format.
1567 Fix for gdb/702: a -var-assign that updates the value now shows up
1568 in a subsequent -var-update.
1570 * New native configurations.
1572 FreeBSD/amd64 x86_64-*-freebsd*
1574 * Multi-arched targets.
1576 HP/PA HPUX11 hppa*-*-hpux*
1577 Renesas M32R/D w/simulator m32r-*-elf*
1579 * OBSOLETE configurations and files
1581 Configurations that have been declared obsolete in this release have
1582 been commented out. Unless there is activity to revive these
1583 configurations, the next release of GDB will have their sources
1584 permanently REMOVED.
1586 Z8000 simulator z8k-zilog-none or z8ksim
1587 Matsushita MN10200 w/simulator mn10200-*-*
1588 H8/500 simulator h8500-hitachi-hms or h8500hms
1589 HP/PA running BSD hppa*-*-bsd*
1590 HP/PA running OSF/1 hppa*-*-osf*
1591 HP/PA Pro target hppa*-*-pro*
1592 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1593 Sequent family i[3456]86-sequent-sysv4*
1594 i[3456]86-sequent-sysv*
1595 i[3456]86-sequent-bsd*
1596 Tsqware Sparclet sparclet-*-*
1597 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1599 * REMOVED configurations and files
1602 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1603 IBM AIX PS/2 i[3456]86-*-aix
1604 i386 running Mach 3.0 i[3456]86-*-mach3*
1605 i386 running Mach i[3456]86-*-mach*
1606 i386 running OSF/1 i[3456]86-*osf1mk*
1607 HP/Apollo 68k Family m68*-apollo*-sysv*,
1609 m68*-hp-bsd*, m68*-hp-hpux*
1610 Argonaut Risc Chip (ARC) arc-*-*
1611 Mitsubishi D30V d30v-*-*
1612 Fujitsu FR30 fr30-*-elf*
1613 OS/9000 i[34]86-*-os9k
1614 I960 with MON960 i960-*-coff
1616 * MIPS $fp behavior changed
1618 The convenience variable $fp, for the MIPS, now consistently returns
1619 the address of the current frame's base. Previously, depending on the
1620 context, $fp could refer to either $sp or the current frame's base
1621 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1622 The GNU Source-Level Debugger''.
1624 *** Changes in GDB 5.3:
1626 * GNU/Linux shared library multi-threaded performance improved.
1628 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1629 `/proc', in preference to `ptrace' for memory reads. This may result
1630 in an improvement in the start-up time of multi-threaded, shared
1631 library applications when run under GDB. One GDB user writes: ``loads
1632 shared libs like mad''.
1634 * ``gdbserver'' now supports multi-threaded applications on some targets
1636 Support for debugging multi-threaded applications which use
1637 the GNU/Linux LinuxThreads package has been added for
1638 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1639 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1641 * GDB now supports C/C++ preprocessor macros.
1643 GDB now expands preprocessor macro invocations in C/C++ expressions,
1644 and provides various commands for showing macro definitions and how
1647 The new command `macro expand EXPRESSION' expands any macro
1648 invocations in expression, and shows the result.
1650 The new command `show macro MACRO-NAME' shows the definition of the
1651 macro named MACRO-NAME, and where it was defined.
1653 Most compilers don't include information about macros in the debugging
1654 information by default. In GCC 3.1, for example, you need to compile
1655 your program with the options `-gdwarf-2 -g3'. If the macro
1656 information is present in the executable, GDB will read it.
1658 * Multi-arched targets.
1660 DEC Alpha (partial) alpha*-*-*
1661 DEC VAX (partial) vax-*-*
1663 National Semiconductor NS32000 (partial) ns32k-*-*
1664 Motorola 68000 (partial) m68k-*-*
1665 Motorola MCORE mcore-*-*
1669 Fujitsu FRV architecture added by Red Hat frv*-*-*
1672 * New native configurations
1674 Alpha NetBSD alpha*-*-netbsd*
1675 SH NetBSD sh*-*-netbsdelf*
1676 MIPS NetBSD mips*-*-netbsd*
1677 UltraSPARC NetBSD sparc64-*-netbsd*
1679 * OBSOLETE configurations and files
1681 Configurations that have been declared obsolete in this release have
1682 been commented out. Unless there is activity to revive these
1683 configurations, the next release of GDB will have their sources
1684 permanently REMOVED.
1686 Mitsubishi D30V d30v-*-*
1687 OS/9000 i[34]86-*-os9k
1688 IBM AIX PS/2 i[3456]86-*-aix
1689 Fujitsu FR30 fr30-*-elf*
1690 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1691 Argonaut Risc Chip (ARC) arc-*-*
1692 i386 running Mach 3.0 i[3456]86-*-mach3*
1693 i386 running Mach i[3456]86-*-mach*
1694 i386 running OSF/1 i[3456]86-*osf1mk*
1695 HP/Apollo 68k Family m68*-apollo*-sysv*,
1697 m68*-hp-bsd*, m68*-hp-hpux*
1698 I960 with MON960 i960-*-coff
1700 * OBSOLETE languages
1702 CHILL, a Pascal like language used by telecommunications companies.
1704 * REMOVED configurations and files
1706 AMD 29k family via UDI a29k-amd-udi, udi29k
1707 A29K VxWorks a29k-*-vxworks
1708 AMD 29000 embedded, using EBMON a29k-none-none
1709 AMD 29000 embedded with COFF a29k-none-coff
1710 AMD 29000 embedded with a.out a29k-none-aout
1712 testsuite/gdb.hp/gdb.threads-hp/ directory
1714 * New command "set max-user-call-depth <nnn>"
1716 This command allows the user to limit the call depth of user-defined
1717 commands. The default is 1024.
1719 * Changes in FreeBSD/i386 native debugging.
1721 Support for the "generate-core-file" has been added.
1723 * New commands "dump", "append", and "restore".
1725 These commands allow data to be copied from target memory
1726 to a bfd-format or binary file (dump and append), and back
1727 from a file into memory (restore).
1729 * Improved "next/step" support on multi-processor Alpha Tru64.
1731 The previous single-step mechanism could cause unpredictable problems,
1732 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1733 of a software single-step mechanism prevents this.
1735 *** Changes in GDB 5.2.1:
1743 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1744 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1745 Fix, by Joel Brobecker imported from mainline.
1747 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1748 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1749 Fix, by Fred Fish, imported from mainline.
1751 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1752 Surprisingly enough, it works now.
1753 By Michal Ludvig, imported from mainline.
1755 i386 hardware watchpoint support:
1756 avoid misses on second run for some targets.
1757 By Pierre Muller, imported from mainline.
1759 *** Changes in GDB 5.2:
1761 * New command "set trust-readonly-sections on[off]".
1763 This command is a hint that tells gdb that read-only sections
1764 really are read-only (ie. that their contents will not change).
1765 In this mode, gdb will go to the object file rather than the
1766 target to read memory from read-only sections (such as ".text").
1767 This can be a significant performance improvement on some
1768 (notably embedded) targets.
1770 * New command "generate-core-file" (or "gcore").
1772 This new gdb command allows the user to drop a core file of the child
1773 process state at any time. So far it's been implemented only for
1774 GNU/Linux and Solaris, but should be relatively easily ported to other
1775 hosts. Argument is core file name (defaults to core.<pid>).
1777 * New command line option
1779 GDB now accepts --pid or -p followed by a process id.
1781 * Change in command line behavior -- corefiles vs. process ids.
1783 There is a subtle behavior in the way in which GDB handles
1784 command line arguments. The first non-flag argument is always
1785 a program to debug, but the second non-flag argument may either
1786 be a corefile or a process id. Previously, GDB would attempt to
1787 open the second argument as a corefile, and if that failed, would
1788 issue a superfluous error message and then attempt to attach it as
1789 a process. Now, if the second argument begins with a non-digit,
1790 it will be treated as a corefile. If it begins with a digit,
1791 GDB will attempt to attach it as a process, and if no such process
1792 is found, will then attempt to open it as a corefile.
1794 * Changes in ARM configurations.
1796 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1797 configuration is fully multi-arch.
1799 * New native configurations
1801 ARM NetBSD arm*-*-netbsd*
1802 x86 OpenBSD i[3456]86-*-openbsd*
1803 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1804 Sparc64 running FreeBSD sparc64-*-freebsd*
1808 Sanyo XStormy16 xstormy16-elf
1810 * OBSOLETE configurations and files
1812 Configurations that have been declared obsolete in this release have
1813 been commented out. Unless there is activity to revive these
1814 configurations, the next release of GDB will have their sources
1815 permanently REMOVED.
1817 AMD 29k family via UDI a29k-amd-udi, udi29k
1818 A29K VxWorks a29k-*-vxworks
1819 AMD 29000 embedded, using EBMON a29k-none-none
1820 AMD 29000 embedded with COFF a29k-none-coff
1821 AMD 29000 embedded with a.out a29k-none-aout
1823 testsuite/gdb.hp/gdb.threads-hp/ directory
1825 * REMOVED configurations and files
1827 TI TMS320C80 tic80-*-*
1829 PowerPC Solaris powerpcle-*-solaris*
1830 PowerPC Windows NT powerpcle-*-cygwin32
1831 PowerPC Netware powerpc-*-netware*
1832 Harris/CXUX m88k m88*-harris-cxux*
1833 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1834 ns32k-utek-sysv* ns32k-utek-*
1835 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1836 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1837 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1838 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1839 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1841 * Changes to command line processing
1843 The new `--args' feature can be used to specify command-line arguments
1844 for the inferior from gdb's command line.
1846 * Changes to key bindings
1848 There is a new `operate-and-get-next' function bound to `C-o'.
1850 *** Changes in GDB 5.1.1
1852 Fix compile problem on DJGPP.
1854 Fix a problem with floating-point registers on the i386 being
1857 Fix to stop GDB crashing on .debug_str debug info.
1859 Numerous documentation fixes.
1861 Numerous testsuite fixes.
1863 *** Changes in GDB 5.1:
1865 * New native configurations
1867 Alpha FreeBSD alpha*-*-freebsd*
1868 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1869 MIPS GNU/Linux mips*-*-linux*
1870 MIPS SGI Irix 6.x mips*-sgi-irix6*
1871 ia64 AIX ia64-*-aix*
1872 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1876 Motorola 68HC11 and 68HC12 m68hc11-elf
1878 UltraSparc running GNU/Linux sparc64-*-linux*
1880 * OBSOLETE configurations and files
1882 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1883 Harris/CXUX m88k m88*-harris-cxux*
1884 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1885 ns32k-utek-sysv* ns32k-utek-*
1886 TI TMS320C80 tic80-*-*
1888 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1889 PowerPC Solaris powerpcle-*-solaris*
1890 PowerPC Windows NT powerpcle-*-cygwin32
1891 PowerPC Netware powerpc-*-netware*
1892 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1893 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1894 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1895 Apple Macintosh (MPW) host N/A
1897 stuff.c (Program to stuff files into a specially prepared space in kdb)
1898 kdb-start.c (Main loop for the standalone kernel debugger)
1900 Configurations that have been declared obsolete in this release have
1901 been commented out. Unless there is activity to revive these
1902 configurations, the next release of GDB will have their sources
1903 permanently REMOVED.
1905 * REMOVED configurations and files
1907 Altos 3068 m68*-altos-*
1908 Convex c1-*-*, c2-*-*
1910 ARM RISCix arm-*-* (as host)
1914 * GDB has been converted to ISO C.
1916 GDB's source code has been converted to ISO C. In particular, the
1917 sources are fully protoized, and rely on standard headers being
1922 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1924 * The MI enabled by default.
1926 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1927 revised and enabled by default. Packages which use GDB as a debugging
1928 engine behind a UI or another front end are encouraged to switch to
1929 using the GDB/MI interface, instead of the old annotations interface
1930 which is now deprecated.
1932 * Support for debugging Pascal programs.
1934 GDB now includes support for debugging Pascal programs. The following
1935 main features are supported:
1937 - Pascal-specific data types such as sets;
1939 - automatic recognition of Pascal sources based on file-name
1942 - Pascal-style display of data types, variables, and functions;
1944 - a Pascal expression parser.
1946 However, some important features are not yet supported.
1948 - Pascal string operations are not supported at all;
1950 - there are some problems with boolean types;
1952 - Pascal type hexadecimal constants are not supported
1953 because they conflict with the internal variables format;
1955 - support for Pascal objects and classes is not full yet;
1957 - unlike Pascal, GDB is case-sensitive for symbol names.
1959 * Changes in completion.
1961 Commands such as `shell', `run' and `set args', which pass arguments
1962 to inferior programs, now complete on file names, similar to what
1963 users expect at the shell prompt.
1965 Commands which accept locations, such as `disassemble', `print',
1966 `breakpoint', `until', etc. now complete on filenames as well as
1967 program symbols. Thus, if you type "break foob TAB", and the source
1968 files linked into the programs include `foobar.c', that file name will
1969 be one of the candidates for completion. However, file names are not
1970 considered for completion after you typed a colon that delimits a file
1971 name from a name of a function in that file, as in "break foo.c:bar".
1973 `set demangle-style' completes on available demangling styles.
1975 * New platform-independent commands:
1977 It is now possible to define a post-hook for a command as well as a
1978 hook that runs before the command. For more details, see the
1979 documentation of `hookpost' in the GDB manual.
1981 * Changes in GNU/Linux native debugging.
1983 Support for debugging multi-threaded programs has been completely
1984 revised for all platforms except m68k and sparc. You can now debug as
1985 many threads as your system allows you to have.
1987 Attach/detach is supported for multi-threaded programs.
1989 Support for SSE registers was added for x86. This doesn't work for
1990 multi-threaded programs though.
1992 * Changes in MIPS configurations.
1994 Multi-arch support is enabled for all MIPS configurations.
1996 GDB can now be built as native debugger on SGI Irix 6.x systems for
1997 debugging n32 executables. (Debugging 64-bit executables is not yet
2000 * Unified support for hardware watchpoints in all x86 configurations.
2002 Most (if not all) native x86 configurations support hardware-assisted
2003 breakpoints and watchpoints in a unified manner. This support
2004 implements debug register sharing between watchpoints, which allows to
2005 put a virtually infinite number of watchpoints on the same address,
2006 and also supports watching regions up to 16 bytes with several debug
2009 The new maintenance command `maintenance show-debug-regs' toggles
2010 debugging print-outs in functions that insert, remove, and test
2011 watchpoints and hardware breakpoints.
2013 * Changes in the DJGPP native configuration.
2015 New command ``info dos sysinfo'' displays assorted information about
2016 the CPU, OS, memory, and DPMI server.
2018 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2019 display information about segment descriptors stored in GDT, LDT, and
2022 New commands ``info dos pde'' and ``info dos pte'' display entries
2023 from Page Directory and Page Tables (for now works with CWSDPMI only).
2024 New command ``info dos address-pte'' displays the Page Table entry for
2025 a given linear address.
2027 GDB can now pass command lines longer than 126 characters to the
2028 program being debugged (requires an update to the libdbg.a library
2029 which is part of the DJGPP development kit).
2031 DWARF2 debug info is now supported.
2033 It is now possible to `step' and `next' through calls to `longjmp'.
2035 * Changes in documentation.
2037 All GDB documentation was converted to GFDL, the GNU Free
2038 Documentation License.
2040 Tracepoints-related commands are now fully documented in the GDB
2043 TUI, the Text-mode User Interface, is now documented in the manual.
2045 Tracepoints-related commands are now fully documented in the GDB
2048 The "GDB Internals" manual now has an index. It also includes
2049 documentation of `ui_out' functions, GDB coding standards, x86
2050 hardware watchpoints, and memory region attributes.
2052 * GDB's version number moved to ``version.in''
2054 The Makefile variable VERSION has been replaced by the file
2055 ``version.in''. People creating GDB distributions should update the
2056 contents of this file.
2060 GUD support is now a standard part of the EMACS distribution.
2062 *** Changes in GDB 5.0:
2064 * Improved support for debugging FP programs on x86 targets
2066 Unified and much-improved support for debugging floating-point
2067 programs on all x86 targets. In particular, ``info float'' now
2068 displays the FP registers in the same format on all x86 targets, with
2069 greater level of detail.
2071 * Improvements and bugfixes in hardware-assisted watchpoints
2073 It is now possible to watch array elements, struct members, and
2074 bitfields with hardware-assisted watchpoints. Data-read watchpoints
2075 on x86 targets no longer erroneously trigger when the address is
2078 * Improvements in the native DJGPP version of GDB
2080 The distribution now includes all the scripts and auxiliary files
2081 necessary to build the native DJGPP version on MS-DOS/MS-Windows
2082 machines ``out of the box''.
2084 The DJGPP version can now debug programs that use signals. It is
2085 possible to catch signals that happened in the debuggee, deliver
2086 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
2087 would kill the program being debugged.) Programs that hook hardware
2088 interrupts (keyboard, timer, etc.) can also be debugged.
2090 It is now possible to debug DJGPP programs that redirect their
2091 standard handles or switch them to raw (as opposed to cooked) mode, or
2092 even close them. The command ``run < foo > bar'' works as expected,
2093 and ``info terminal'' reports useful information about the debuggee's
2094 terminal, including raw/cooked mode, redirection, etc.
2096 The DJGPP version now uses termios functions for console I/O, which
2097 enables debugging graphics programs. Interrupting GDB with Ctrl-C
2100 DOS-style file names with drive letters are now fully supported by
2103 It is now possible to debug DJGPP programs that switch their working
2104 directory. It is also possible to rerun the debuggee any number of
2105 times without restarting GDB; thus, you can use the same setup,
2106 breakpoints, etc. for many debugging sessions.
2108 * New native configurations
2110 ARM GNU/Linux arm*-*-linux*
2111 PowerPC GNU/Linux powerpc-*-linux*
2115 Motorola MCore mcore-*-*
2116 x86 VxWorks i[3456]86-*-vxworks*
2117 PowerPC VxWorks powerpc-*-vxworks*
2118 TI TMS320C80 tic80-*-*
2120 * OBSOLETE configurations
2122 Altos 3068 m68*-altos-*
2123 Convex c1-*-*, c2-*-*
2125 ARM RISCix arm-*-* (as host)
2128 Configurations that have been declared obsolete will be commented out,
2129 but the code will be left in place. If there is no activity to revive
2130 these configurations before the next release of GDB, the sources will
2131 be permanently REMOVED.
2133 * Gould support removed
2135 Support for the Gould PowerNode and NP1 has been removed.
2137 * New features for SVR4
2139 On SVR4 native platforms (such as Solaris), if you attach to a process
2140 without first loading a symbol file, GDB will now attempt to locate and
2141 load symbols from the running process's executable file.
2143 * Many C++ enhancements
2145 C++ support has been greatly improved. Overload resolution now works properly
2146 in almost all cases. RTTI support is on the way.
2148 * Remote targets can connect to a sub-program
2150 A popen(3) style serial-device has been added. This device starts a
2151 sub-process (such as a stand-alone simulator) and then communicates
2152 with that. The sub-program to run is specified using the syntax
2153 ``|<program> <args>'' vis:
2155 (gdb) set remotedebug 1
2156 (gdb) target extended-remote |mn10300-elf-sim program-args
2158 * MIPS 64 remote protocol
2160 A long standing bug in the mips64 remote protocol where by GDB
2161 expected certain 32 bit registers (ex SR) to be transfered as 32
2162 instead of 64 bits has been fixed.
2164 The command ``set remote-mips64-transfers-32bit-regs on'' has been
2165 added to provide backward compatibility with older versions of GDB.
2167 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
2169 The command ``set remotebinarydownload'' command has been replaced by
2170 ``set remote X-packet''. Other commands in ``set remote'' family
2171 include ``set remote P-packet''.
2173 * Breakpoint commands accept ranges.
2175 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
2176 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
2177 ``tracepoint passcount'' also accepts a range of tracepoints.
2179 * ``apropos'' command added.
2181 The ``apropos'' command searches through command names and
2182 documentation strings, printing out matches, making it much easier to
2183 try to find a command that does what you are looking for.
2187 A new machine oriented interface (MI) has been added to GDB. This
2188 interface is designed for debug environments running GDB as a separate
2189 process. This is part of the long term libGDB project. See the
2190 "GDB/MI" chapter of the GDB manual for further information. It can be
2191 enabled by configuring with:
2193 .../configure --enable-gdbmi
2195 *** Changes in GDB-4.18:
2197 * New native configurations
2199 HP-UX 10.20 hppa*-*-hpux10.20
2200 HP-UX 11.x hppa*-*-hpux11.0*
2201 M68K GNU/Linux m68*-*-linux*
2205 Fujitsu FR30 fr30-*-elf*
2206 Intel StrongARM strongarm-*-*
2207 Mitsubishi D30V d30v-*-*
2209 * OBSOLETE configurations
2211 Gould PowerNode, NP1 np1-*-*, pn-*-*
2213 Configurations that have been declared obsolete will be commented out,
2214 but the code will be left in place. If there is no activity to revive
2215 these configurations before the next release of GDB, the sources will
2216 be permanently REMOVED.
2220 As a compatibility experiment, GDB's source files buildsym.h and
2221 buildsym.c have been converted to pure standard C, no longer
2222 containing any K&R compatibility code. We believe that all systems in
2223 use today either come with a standard C compiler, or have a GCC port
2224 available. If this is not true, please report the affected
2225 configuration to bug-gdb@gnu.org immediately. See the README file for
2226 information about getting a standard C compiler if you don't have one
2231 GDB now uses readline 2.2.
2233 * set extension-language
2235 You can now control the mapping between filename extensions and source
2236 languages by using the `set extension-language' command. For instance,
2237 you can ask GDB to treat .c files as C++ by saying
2238 set extension-language .c c++
2239 The command `info extensions' lists all of the recognized extensions
2240 and their associated languages.
2242 * Setting processor type for PowerPC and RS/6000
2244 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
2245 you can use the `set processor' command to specify what variant of the
2246 PowerPC family you are debugging. The command
2250 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
2251 following PowerPC and RS6000 variants:
2253 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
2254 rs6000 IBM RS6000 ("POWER") architecture, user-level view
2256 403GC IBM PowerPC 403GC
2257 505 Motorola PowerPC 505
2258 860 Motorola PowerPC 860 or 850
2259 601 Motorola PowerPC 601
2260 602 Motorola PowerPC 602
2261 603 Motorola/IBM PowerPC 603 or 603e
2262 604 Motorola PowerPC 604 or 604e
2263 750 Motorola/IBM PowerPC 750 or 750
2265 At the moment, this command just tells GDB what to name the
2266 special-purpose processor registers. Since almost all the affected
2267 registers are inaccessible to user-level programs, this command is
2268 only useful for remote debugging in its present form.
2272 Thanks to a major code donation from Hewlett-Packard, GDB now has much
2273 more extensive support for HP-UX. Added features include shared
2274 library support, kernel threads and hardware watchpoints for 11.00,
2275 support for HP's ANSI C and C++ compilers, and a compatibility mode
2276 for xdb and dbx commands.
2280 HP's donation includes the new concept of catchpoints, which is a
2281 generalization of the old catch command. On HP-UX, it is now possible
2282 to catch exec, fork, and vfork, as well as library loading.
2284 This means that the existing catch command has changed; its first
2285 argument now specifies the type of catch to be set up. See the
2286 output of "help catch" for a list of catchpoint types.
2288 * Debugging across forks
2290 On HP-UX, you can choose which process to debug when a fork() happens
2295 HP has donated a curses-based terminal user interface (TUI). To get
2296 it, build with --enable-tui. Although this can be enabled for any
2297 configuration, at present it only works for native HP debugging.
2299 * GDB remote protocol additions
2301 A new protocol packet 'X' that writes binary data is now available.
2302 Default behavior is to try 'X', then drop back to 'M' if the stub
2303 fails to respond. The settable variable `remotebinarydownload'
2304 allows explicit control over the use of 'X'.
2306 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
2307 full 64-bit address. The command
2309 set remoteaddresssize 32
2311 can be used to revert to the old behaviour. For existing remote stubs
2312 the change should not be noticed, as the additional address information
2315 In order to assist in debugging stubs, you may use the maintenance
2316 command `packet' to send any text string to the stub. For instance,
2318 maint packet heythere
2320 sends the packet "$heythere#<checksum>". Note that it is very easy to
2321 disrupt a debugging session by sending the wrong packet at the wrong
2324 The compare-sections command allows you to compare section data on the
2325 target to what is in the executable file without uploading or
2326 downloading, by comparing CRC checksums.
2328 * Tracing can collect general expressions
2330 You may now collect general expressions at tracepoints. This requires
2331 further additions to the target-side stub; see tracepoint.c and
2332 doc/agentexpr.texi for further details.
2334 * mask-address variable for Mips
2336 For Mips targets, you may control the zeroing of the upper 32 bits of
2337 a 64-bit address by entering `set mask-address on'. This is mainly
2338 of interest to users of embedded R4xxx and R5xxx processors.
2340 * Higher serial baud rates
2342 GDB's serial code now allows you to specify baud rates 57600, 115200,
2343 230400, and 460800 baud. (Note that your host system may not be able
2344 to achieve all of these rates.)
2348 The i960 configuration now includes an initial implementation of a
2349 builtin simulator, contributed by Jim Wilson.
2352 *** Changes in GDB-4.17:
2354 * New native configurations
2356 Alpha GNU/Linux alpha*-*-linux*
2357 Unixware 2.x i[3456]86-unixware2*
2358 Irix 6.x mips*-sgi-irix6*
2359 PowerPC GNU/Linux powerpc-*-linux*
2360 PowerPC Solaris powerpcle-*-solaris*
2361 Sparc GNU/Linux sparc-*-linux*
2362 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2366 Argonaut Risc Chip (ARC) arc-*-*
2367 Hitachi H8/300S h8300*-*-*
2368 Matsushita MN10200 w/simulator mn10200-*-*
2369 Matsushita MN10300 w/simulator mn10300-*-*
2370 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2371 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2372 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2373 Mitsubishi D10V w/simulator d10v-*-*
2374 Mitsubishi M32R/D w/simulator m32r-*-elf*
2375 Tsqware Sparclet sparclet-*-*
2376 NEC V850 w/simulator v850-*-*
2378 * New debugging protocols
2380 ARM with RDI protocol arm*-*-*
2381 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2382 DDB and LSI variants of PMON protocol mips*-*-*
2383 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2384 PowerPC with SDS protocol powerpc{,le}-*-eabi
2385 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2389 All configurations can now understand and use the DWARF 2 debugging
2390 format. The choice is automatic, if the symbol file contains DWARF 2
2395 GDB now includes basic Java language support. This support is
2396 only useful with Java compilers that produce native machine code.
2398 * solib-absolute-prefix and solib-search-path
2400 For SunOS and SVR4 shared libraries, you may now set the prefix for
2401 loading absolute shared library symbol files, and the search path for
2402 locating non-absolute shared library symbol files.
2404 * Live range splitting
2406 GDB can now effectively debug code for which GCC has performed live
2407 range splitting as part of its optimization. See gdb/doc/LRS for
2408 more details on the expected format of the stabs information.
2412 GDB's support for the GNU Hurd, including thread debugging, has been
2413 updated to work with current versions of the Hurd.
2417 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2418 instruction set. ARM GDB automatically detects when Thumb
2419 instructions are in use, and adjusts disassembly and backtracing
2424 GDB's MIPS target configurations now handle the MIP16 16-bit
2429 GDB now includes support for overlays; if an executable has been
2430 linked such that multiple sections are based at the same address, GDB
2431 will decide which section to use for symbolic info. You can choose to
2432 control the decision manually, using overlay commands, or implement
2433 additional target-side support and use "overlay load-target" to bring
2434 in the overlay mapping. Do "help overlay" for more detail.
2438 The command "info symbol <address>" displays information about
2439 the symbol at the specified address.
2443 The standard remote protocol now includes an extension that allows
2444 asynchronous collection and display of trace data. This requires
2445 extensive support in the target-side debugging stub. Tracing mode
2446 includes a new interaction mode in GDB and new commands: see the
2447 file tracepoint.c for more details.
2451 Configurations for embedded MIPS now include a simulator contributed
2452 by Cygnus Solutions. The simulator supports the instruction sets
2453 of most MIPS variants.
2457 Sparc configurations may now include the ERC32 simulator contributed
2458 by the European Space Agency. The simulator is not built into
2459 Sparc targets by default; configure with --enable-sim to include it.
2463 For target configurations that may include multiple variants of a
2464 basic architecture (such as MIPS and SH), you may now set the
2465 architecture explicitly. "set arch" sets, "info arch" lists
2466 the possible architectures.
2468 *** Changes in GDB-4.16:
2470 * New native configurations
2472 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2473 M68K NetBSD m68k-*-netbsd*
2474 PowerPC AIX 4.x powerpc-*-aix*
2475 PowerPC MacOS powerpc-*-macos*
2476 PowerPC Windows NT powerpcle-*-cygwin32
2477 RS/6000 AIX 4.x rs6000-*-aix4*
2481 ARM with RDP protocol arm-*-*
2482 I960 with MON960 i960-*-coff
2483 MIPS VxWorks mips*-*-vxworks*
2484 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2485 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2487 Matra Sparclet sparclet-*-*
2491 The powerpc-eabi configuration now includes the PSIM simulator,
2492 contributed by Andrew Cagney, with assistance from Mike Meissner.
2493 PSIM is a very elaborate model of the PowerPC, including not only
2494 basic instruction set execution, but also details of execution unit
2495 performance and I/O hardware. See sim/ppc/README for more details.
2499 GDB now works with Solaris 2.5.
2501 * Windows 95/NT native
2503 GDB will now work as a native debugger on Windows 95 and Windows NT.
2504 To build it from source, you must use the "gnu-win32" environment,
2505 which uses a DLL to emulate enough of Unix to run the GNU tools.
2506 Further information, binaries, and sources are available at
2507 ftp.cygnus.com, under pub/gnu-win32.
2509 * dont-repeat command
2511 If a user-defined command includes the command `dont-repeat', then the
2512 command will not be repeated if the user just types return. This is
2513 useful if the command is time-consuming to run, so that accidental
2514 extra keystrokes don't run the same command many times.
2516 * Send break instead of ^C
2518 The standard remote protocol now includes an option to send a break
2519 rather than a ^C to the target in order to interrupt it. By default,
2520 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2522 * Remote protocol timeout
2524 The standard remote protocol includes a new variable `remotetimeout'
2525 that allows you to set the number of seconds before GDB gives up trying
2526 to read from the target. The default value is 2.
2528 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2530 By default GDB will automatically keep track of objects as they are
2531 loaded and unloaded by the dynamic linker. By using the command `set
2532 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2533 when shared library events occur, thus allowing you to set breakpoints
2534 in shared libraries which are explicitly loaded by the inferior.
2536 Note this feature does not work on hpux8. On hpux9 you must link
2537 /usr/lib/end.o into your program. This feature should work
2538 automatically on hpux10.
2540 * Irix 5.x hardware watchpoint support
2542 Irix 5 configurations now support the use of hardware watchpoints.
2544 * Mips protocol "SYN garbage limit"
2546 When debugging a Mips target using the `target mips' protocol, you
2547 may set the number of characters that GDB will ignore by setting
2548 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2549 every character. The default value is 1050.
2551 * Recording and replaying remote debug sessions
2553 If you set `remotelogfile' to the name of a file, gdb will write to it
2554 a recording of a remote debug session. This recording may then be
2555 replayed back to gdb using "gdbreplay". See gdbserver/README for
2556 details. This is useful when you have a problem with GDB while doing
2557 remote debugging; you can make a recording of the session and send it
2558 to someone else, who can then recreate the problem.
2560 * Speedups for remote debugging
2562 GDB includes speedups for downloading and stepping MIPS systems using
2563 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2564 and more efficient S-record downloading.
2566 * Memory use reductions and statistics collection
2568 GDB now uses less memory and reports statistics about memory usage.
2569 Try the `maint print statistics' command, for example.
2571 *** Changes in GDB-4.15:
2573 * Psymtabs for XCOFF
2575 The symbol reader for AIX GDB now uses partial symbol tables. This
2576 can greatly improve startup time, especially for large executables.
2578 * Remote targets use caching
2580 Remote targets now use a data cache to speed up communication with the
2581 remote side. The data cache could lead to incorrect results because
2582 it doesn't know about volatile variables, thus making it impossible to
2583 debug targets which use memory mapped I/O devices. `set remotecache
2584 off' turns the the data cache off.
2586 * Remote targets may have threads
2588 The standard remote protocol now includes support for multiple threads
2589 in the target system, using new protocol commands 'H' and 'T'. See
2590 gdb/remote.c for details.
2594 If GDB is configured with `--enable-netrom', then it will include
2595 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2596 acts as though it is a bank of ROM on the target board, but you can
2597 write into it over the network. GDB's support consists only of
2598 support for fast loading into the emulated ROM; to debug, you must use
2599 another protocol, such as standard remote protocol. The usual
2600 sequence is something like
2602 target nrom <netrom-hostname>
2604 target remote <netrom-hostname>:1235
2608 GDB now includes support for the Apple Macintosh, as a host only. It
2609 may be run as either an MPW tool or as a standalone application, and
2610 it can debug through the serial port. All the usual GDB commands are
2611 available, but to the target command, you must supply "serial" as the
2612 device type instead of "/dev/ttyXX". See mpw-README in the main
2613 directory for more information on how to build. The MPW configuration
2614 scripts */mpw-config.in support only a few targets, and only the
2615 mips-idt-ecoff target has been tested.
2619 GDB configuration now uses autoconf. This is not user-visible,
2620 but does simplify configuration and building.
2624 GDB now supports hpux10.
2626 *** Changes in GDB-4.14:
2628 * New native configurations
2630 x86 FreeBSD i[345]86-*-freebsd
2631 x86 NetBSD i[345]86-*-netbsd
2632 NS32k NetBSD ns32k-*-netbsd
2633 Sparc NetBSD sparc-*-netbsd
2637 A29K VxWorks a29k-*-vxworks
2638 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2639 CPU32 EST-300 emulator m68*-*-est*
2640 PowerPC ELF powerpc-*-elf
2643 * Alpha OSF/1 support for procfs
2645 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2646 possible to attach to running processes. As the mounting of the /proc
2647 filesystem is optional on the Alpha, GDB automatically determines
2648 the availability of /proc during startup. This can lead to problems
2649 if /proc is unmounted after GDB has been started.
2651 * Arguments to user-defined commands
2653 User commands may accept up to 10 arguments separated by whitespace.
2654 Arguments are accessed within the user command via $arg0..$arg9. A
2657 print $arg0 + $arg1 + $arg2
2659 To execute the command use:
2662 Defines the command "adder" which prints the sum of its three arguments.
2663 Note the arguments are text substitutions, so they may reference variables,
2664 use complex expressions, or even perform inferior function calls.
2666 * New `if' and `while' commands
2668 This makes it possible to write more sophisticated user-defined
2669 commands. Both commands take a single argument, which is the
2670 expression to evaluate, and must be followed by the commands to
2671 execute, one per line, if the expression is nonzero, the list being
2672 terminated by the word `end'. The `if' command list may include an
2673 `else' word, which causes the following commands to be executed only
2674 if the expression is zero.
2676 * Fortran source language mode
2678 GDB now includes partial support for Fortran 77. It will recognize
2679 Fortran programs and can evaluate a subset of Fortran expressions, but
2680 variables and functions may not be handled correctly. GDB will work
2681 with G77, but does not yet know much about symbols emitted by other
2684 * Better HPUX support
2686 Most debugging facilities now work on dynamic executables for HPPAs
2687 running hpux9 or later. You can attach to running dynamically linked
2688 processes, but by default the dynamic libraries will be read-only, so
2689 for instance you won't be able to put breakpoints in them. To change
2690 that behavior do the following before running the program:
2696 This will cause the libraries to be mapped private and read-write.
2697 To revert to the normal behavior, do this:
2703 You cannot set breakpoints or examine data in the library until after
2704 the library is loaded if the function/data symbols do not have
2707 GDB can now also read debug symbols produced by the HP C compiler on
2708 HPPAs (sorry, no C++, Fortran or 68k support).
2710 * Target byte order now dynamically selectable
2712 You can choose which byte order to use with a target system, via the
2713 commands "set endian big" and "set endian little", and you can see the
2714 current setting by using "show endian". You can also give the command
2715 "set endian auto", in which case GDB will use the byte order
2716 associated with the executable. Currently, only embedded MIPS
2717 configurations support dynamic selection of target byte order.
2719 * New DOS host serial code
2721 This version uses DPMI interrupts to handle buffered I/O, so you
2722 no longer need to run asynctsr when debugging boards connected to
2725 *** Changes in GDB-4.13:
2727 * New "complete" command
2729 This lists all the possible completions for the rest of the line, if it
2730 were to be given as a command itself. This is intended for use by emacs.
2732 * Trailing space optional in prompt
2734 "set prompt" no longer adds a space for you after the prompt you set. This
2735 allows you to set a prompt which ends in a space or one that does not.
2737 * Breakpoint hit counts
2739 "info break" now displays a count of the number of times the breakpoint
2740 has been hit. This is especially useful in conjunction with "ignore"; you
2741 can ignore a large number of breakpoint hits, look at the breakpoint info
2742 to see how many times the breakpoint was hit, then run again, ignoring one
2743 less than that number, and this will get you quickly to the last hit of
2746 * Ability to stop printing at NULL character
2748 "set print null-stop" will cause GDB to stop printing the characters of
2749 an array when the first NULL is encountered. This is useful when large
2750 arrays actually contain only short strings.
2752 * Shared library breakpoints
2754 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2755 breakpoints in shared libraries before the executable is run.
2757 * Hardware watchpoints
2759 There is a new hardware breakpoint for the watch command for sparclite
2760 targets. See gdb/sparclite/hw_breakpoint.note.
2762 Hardware watchpoints are also now supported under GNU/Linux.
2766 Annotations have been added. These are for use with graphical interfaces,
2767 and are still experimental. Currently only gdba.el uses these.
2769 * Improved Irix 5 support
2771 GDB now works properly with Irix 5.2.
2773 * Improved HPPA support
2775 GDB now works properly with the latest GCC and GAS.
2777 * New native configurations
2779 Sequent PTX4 i[34]86-sequent-ptx4
2780 HPPA running OSF/1 hppa*-*-osf*
2781 Atari TT running SVR4 m68*-*-sysv4*
2782 RS/6000 LynxOS rs6000-*-lynxos*
2786 OS/9000 i[34]86-*-os9k
2787 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2790 * Hitachi SH7000 and E7000-PC ICE support
2792 There is now support for communicating with the Hitachi E7000-PC ICE.
2793 This is available automatically when GDB is configured for the SH.
2797 As usual, a variety of small fixes and improvements, both generic
2798 and configuration-specific. See the ChangeLog for more detail.
2800 *** Changes in GDB-4.12:
2802 * Irix 5 is now supported
2806 GDB-4.12 on the HPPA has a number of changes which make it unable
2807 to debug the output from the currently released versions of GCC and
2808 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2809 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2810 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2813 *** Changes in GDB-4.11:
2815 * User visible changes:
2819 The "set remotedebug" option is now consistent between the mips remote
2820 target, remote targets using the gdb-specific protocol, UDI (AMD's
2821 debug protocol for the 29k) and the 88k bug monitor. It is now an
2822 integer specifying a debug level (normally 0 or 1, but 2 means more
2823 debugging info for the mips target).
2825 * DEC Alpha native support
2827 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2828 debug info, but GDB works fairly well with the DEC compiler and should
2829 work with a future GCC release. See the README file for a few
2830 Alpha-specific notes.
2832 * Preliminary thread implementation
2834 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2836 * LynxOS native and target support for 386
2838 This release has been hosted on LynxOS 2.2, and also can be configured
2839 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2842 * Improvements in C++ mangling/demangling.
2844 This release has much better g++ debugging, specifically in name
2845 mangling/demangling, virtual function calls, print virtual table,
2846 call methods, ...etc.
2848 *** Changes in GDB-4.10:
2850 * User visible changes:
2852 Remote debugging using the GDB-specific (`target remote') protocol now
2853 supports the `load' command. This is only useful if you have some
2854 other way of getting the stub to the target system, and you can put it
2855 somewhere in memory where it won't get clobbered by the download.
2857 Filename completion now works.
2859 When run under emacs mode, the "info line" command now causes the
2860 arrow to point to the line specified. Also, "info line" prints
2861 addresses in symbolic form (as well as hex).
2863 All vxworks based targets now support a user settable option, called
2864 vxworks-timeout. This option represents the number of seconds gdb
2865 should wait for responses to rpc's. You might want to use this if
2866 your vxworks target is, perhaps, a slow software simulator or happens
2867 to be on the far side of a thin network line.
2871 This release contains support for using a DEC alpha as a GDB host for
2872 cross debugging. Native alpha debugging is not supported yet.
2875 *** Changes in GDB-4.9:
2879 This is the first GDB release which is accompanied by a matching testsuite.
2880 The testsuite requires installation of dejagnu, which should be available
2881 via ftp from most sites that carry GNU software.
2885 'Cfront' style demangling has had its name changed to 'ARM' style, to
2886 emphasize that it was written from the specifications in the C++ Annotated
2887 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2888 disclaimers, it still generated too much confusion with users attempting to
2889 use gdb with AT&T cfront.
2893 GDB now uses a standard remote interface to a simulator library.
2894 So far, the library contains simulators for the Zilog Z8001/2, the
2895 Hitachi H8/300, H8/500 and Super-H.
2897 * New targets supported
2899 H8/300 simulator h8300-hitachi-hms or h8300hms
2900 H8/500 simulator h8500-hitachi-hms or h8500hms
2901 SH simulator sh-hitachi-hms or sh
2902 Z8000 simulator z8k-zilog-none or z8ksim
2903 IDT MIPS board over serial line mips-idt-ecoff
2905 Cross-debugging to GO32 targets is supported. It requires a custom
2906 version of the i386-stub.c module which is integrated with the
2907 GO32 memory extender.
2909 * New remote protocols
2911 MIPS remote debugging protocol.
2913 * New source languages supported
2915 This version includes preliminary support for Chill, a Pascal like language
2916 used by telecommunications companies. Chill support is also being integrated
2917 into the GNU compiler, but we don't know when it will be publically available.
2920 *** Changes in GDB-4.8:
2922 * HP Precision Architecture supported
2924 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2925 version of this support was available as a set of patches from the
2926 University of Utah. GDB does not support debugging of programs
2927 compiled with the HP compiler, because HP will not document their file
2928 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2929 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2931 Many problems in the preliminary version have been fixed.
2933 * Faster and better demangling
2935 We have improved template demangling and fixed numerous bugs in the GNU style
2936 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2937 character types (wchar_t) are now supported. Demangling of each symbol is now
2938 only done once, and is cached when the symbol table for a file is read in.
2939 This results in a small increase in memory usage for C programs, a moderate
2940 increase in memory usage for C++ programs, and a fantastic speedup in
2943 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2944 from the specifications in the Annotated Reference Manual, which AT&T's
2945 compiler does not actually implement.
2947 * G++ multiple inheritance compiler problem
2949 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2950 inheritance lattices was reworked to properly discover ambiguities. We
2951 recently found an example which causes this new algorithm to fail in a
2952 very subtle way, producing bad debug information for those classes.
2953 The file 'gcc.patch' (in this directory) can be applied to gcc to
2954 circumvent the problem. A future GCC release will contain a complete
2957 The previous G++ debug info problem (mentioned below for the gdb-4.7
2958 release) is fixed in gcc version 2.3.2.
2960 * Improved configure script
2962 The `configure' script will now attempt to guess your system type if
2963 you don't supply a host system type. The old scheme of supplying a
2964 host system triplet is preferable over using this. All the magic is
2965 done in the new `config.guess' script. Examine it for details.
2967 We have also brought our configure script much more in line with the FSF's
2968 version. It now supports the --with-xxx options. In particular,
2969 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2970 The resulting GDB will not be able to read arbitrary object file formats --
2971 only the format ``expected'' to be used on the configured target system.
2972 We hope to make this the default in a future release.
2974 * Documentation improvements
2976 There's new internal documentation on how to modify GDB, and how to
2977 produce clean changes to the code. We implore people to read it
2978 before submitting changes.
2980 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2981 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2982 `info' files are also provided. To build `info' files from scratch,
2983 you will need the latest `makeinfo' release, which will be available in
2984 a future texinfo-X.Y release.
2986 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2987 We're not sure exactly which versions have this problem, but it has
2988 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2989 or better. If that isn't possible, there is a patch in
2990 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2991 around this problem.
2995 GDB now supports array constants that can be used in expressions typed in by
2996 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2997 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3000 The new directory `gdb/sparclite' contains a program that demonstrates
3001 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3003 * New native hosts supported
3005 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3006 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3008 * New targets supported
3010 AMD 29k family via UDI a29k-amd-udi or udi29k
3012 * New file formats supported
3014 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3015 HPUX core files, and SCO 3.2v2 core files.
3019 Attaching to processes now works again; thanks for the many bug reports.
3021 We have also stomped on a bunch of core dumps caused by
3022 printf_filtered("%s") problems.
3024 We eliminated a copyright problem on the rpc and ptrace header files
3025 for VxWorks, which was discovered at the last minute during the 4.7
3026 release. You should now be able to build a VxWorks GDB.
3028 You can now interrupt gdb while an attached process is running. This
3029 will cause the attached process to stop, and give control back to GDB.
3031 We fixed problems caused by using too many file descriptors
3032 for reading symbols from object files and libraries. This was
3033 especially a problem for programs that used many (~100) shared
3036 The `step' command now only enters a subroutine if there is line number
3037 information for the subroutine. Otherwise it acts like the `next'
3038 command. Previously, `step' would enter subroutines if there was
3039 any debugging information about the routine. This avoids problems
3040 when using `cc -g1' on MIPS machines.
3042 * Internal improvements
3044 GDB's internal interfaces have been improved to make it easier to support
3045 debugging of multiple languages in the future.
3047 GDB now uses a common structure for symbol information internally.
3048 Minimal symbols (derived from linkage symbols in object files), partial
3049 symbols (from a quick scan of debug information), and full symbols
3050 contain a common subset of information, making it easier to write
3051 shared code that handles any of them.
3053 * New command line options
3055 We now accept --silent as an alias for --quiet.
3059 The memory-mapped-malloc library is now licensed under the GNU Library
3060 General Public License.
3062 *** Changes in GDB-4.7:
3064 * Host/native/target split
3066 GDB has had some major internal surgery to untangle the support for
3067 hosts and remote targets. Now, when you configure GDB for a remote
3068 target, it will no longer load in all of the support for debugging
3069 local programs on the host. When fully completed and tested, this will
3070 ensure that arbitrary host/target combinations are possible.
3072 The primary conceptual shift is to separate the non-portable code in
3073 GDB into three categories. Host specific code is required any time GDB
3074 is compiled on that host, regardless of the target. Target specific
3075 code relates to the peculiarities of the target, but can be compiled on
3076 any host. Native specific code is everything else: it can only be
3077 built when the host and target are the same system. Child process
3078 handling and core file support are two common `native' examples.
3080 GDB's use of /proc for controlling Unix child processes is now cleaner.
3081 It has been split out into a single module under the `target_ops' vector,
3082 plus two native-dependent functions for each system that uses /proc.
3084 * New hosts supported
3086 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
3087 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3088 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
3090 * New targets supported
3092 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
3093 68030 and CPU32 m68030-*-*, m68332-*-*
3095 * New native hosts supported
3097 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
3098 (386bsd is not well tested yet)
3099 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
3101 * New file formats supported
3103 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
3104 supports reading of `a.out.adobe' object files, which are an a.out
3105 format extended with minimal information about multiple sections.
3109 `show copying' is the same as the old `info copying'.
3110 `show warranty' is the same as `info warrantee'.
3111 These were renamed for consistency. The old commands continue to work.
3113 `info handle' is a new alias for `info signals'.
3115 You can now define pre-command hooks, which attach arbitrary command
3116 scripts to any command. The commands in the hook will be executed
3117 prior to the user's command. You can also create a hook which will be
3118 executed whenever the program stops. See gdb.texinfo.
3122 We now deal with Cfront style name mangling, and can even extract type
3123 info from mangled symbols. GDB can automatically figure out which
3124 symbol mangling style your C++ compiler uses.
3126 Calling of methods and virtual functions has been improved as well.
3130 The crash that occured when debugging Sun Ansi-C compiled binaries is
3131 fixed. This was due to mishandling of the extra N_SO stabs output
3134 We also finally got Ultrix 4.2 running in house, and fixed core file
3135 support, with help from a dozen people on the net.
3137 John M. Farrell discovered that the reason that single-stepping was so
3138 slow on all of the Mips based platforms (primarily SGI and DEC) was
3139 that we were trying to demangle and lookup a symbol used for internal
3140 purposes on every instruction that was being stepped through. Changing
3141 the name of that symbol so that it couldn't be mistaken for a C++
3142 mangled symbol sped things up a great deal.
3144 Rich Pixley sped up symbol lookups in general by getting much smarter
3145 about when C++ symbol mangling is necessary. This should make symbol
3146 completion (TAB on the command line) much faster. It's not as fast as
3147 we'd like, but it's significantly faster than gdb-4.6.
3151 A new user controllable variable 'call_scratch_address' can
3152 specify the location of a scratch area to be used when GDB
3153 calls a function in the target. This is necessary because the
3154 usual method of putting the scratch area on the stack does not work
3155 in systems that have separate instruction and data spaces.
3157 We integrated changes to support the 29k UDI (Universal Debugger
3158 Interface), but discovered at the last minute that we didn't have all
3159 of the appropriate copyright paperwork. We are working with AMD to
3160 resolve this, and hope to have it available soon.
3164 We have sped up the remote serial line protocol, especially for targets
3165 with lots of registers. It now supports a new `expedited status' ('T')
3166 message which can be used in place of the existing 'S' status message.
3167 This allows the remote stub to send only the registers that GDB
3168 needs to make a quick decision about single-stepping or conditional
3169 breakpoints, eliminating the need to fetch the entire register set for
3170 each instruction being stepped through.
3172 The GDB remote serial protocol now implements a write-through cache for
3173 registers, only re-reading the registers if the target has run.
3175 There is also a new remote serial stub for SPARC processors. You can
3176 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
3177 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
3178 processor with a serial port.
3182 Configure.in files have become much easier to read and modify. A new
3183 `table driven' format makes it more obvious what configurations are
3184 supported, and what files each one uses.
3188 There is a new opcodes library which will eventually contain all of the
3189 disassembly routines and opcode tables. At present, it only contains
3190 Sparc and Z8000 routines. This will allow the assembler, debugger, and
3191 disassembler (binutils/objdump) to share these routines.
3193 The libiberty library is now copylefted under the GNU Library General
3194 Public License. This allows more liberal use, and was done so libg++
3195 can use it. This makes no difference to GDB, since the Library License
3196 grants all the rights from the General Public License.
3200 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
3201 reference to the stabs symbol info used by the debugger. It is (as far
3202 as we know) the only published document on this fascinating topic. We
3203 encourage you to read it, compare it to the stabs information on your
3204 system, and send improvements on the document in general (to
3205 bug-gdb@prep.ai.mit.edu).
3207 And, of course, many bugs have been fixed.
3210 *** Changes in GDB-4.6:
3212 * Better support for C++ function names
3214 GDB now accepts as input the "demangled form" of C++ overloaded function
3215 names and member function names, and can do command completion on such names
3216 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
3217 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
3218 Make use of command completion, it is your friend.
3220 GDB also now accepts a variety of C++ mangled symbol formats. They are
3221 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
3222 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
3223 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
3224 for the list of formats.
3226 * G++ symbol mangling problem
3228 Recent versions of gcc have a bug in how they emit debugging information for
3229 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
3230 directory) can be applied to gcc to fix the problem. Alternatively, if you
3231 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
3232 usual symptom is difficulty with setting breakpoints on methods. GDB complains
3233 about the method being non-existent. (We believe that version 2.2.2 of GCC has
3236 * New 'maintenance' command
3238 All of the commands related to hacking GDB internals have been moved out of
3239 the main command set, and now live behind the 'maintenance' command. This
3240 can also be abbreviated as 'mt'. The following changes were made:
3242 dump-me -> maintenance dump-me
3243 info all-breakpoints -> maintenance info breakpoints
3244 printmsyms -> maintenance print msyms
3245 printobjfiles -> maintenance print objfiles
3246 printpsyms -> maintenance print psymbols
3247 printsyms -> maintenance print symbols
3249 The following commands are new:
3251 maintenance demangle Call internal GDB demangler routine to
3252 demangle a C++ link name and prints the result.
3253 maintenance print type Print a type chain for a given symbol
3255 * Change to .gdbinit file processing
3257 We now read the $HOME/.gdbinit file before processing the argv arguments
3258 (e.g. reading symbol files or core files). This allows global parameters to
3259 be set, which will apply during the symbol reading. The ./.gdbinit is still
3260 read after argv processing.
3262 * New hosts supported
3264 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
3266 GNU/Linux support i386-unknown-linux or linux
3268 We are also including code to support the HP/PA running BSD and HPUX. This
3269 is almost guaranteed not to work, as we didn't have time to test or build it
3270 for this release. We are including it so that the more adventurous (or
3271 masochistic) of you can play with it. We also had major problems with the
3272 fact that the compiler that we got from HP doesn't support the -g option.
3275 * New targets supported
3277 Hitachi H8/300 h8300-hitachi-hms or h8300hms
3279 * More smarts about finding #include files
3281 GDB now remembers the compilation directory for all include files, and for
3282 all files from which C is generated (like yacc and lex sources). This
3283 greatly improves GDB's ability to find yacc/lex sources, and include files,
3284 especially if you are debugging your program from a directory different from
3285 the one that contains your sources.
3287 We also fixed a bug which caused difficulty with listing and setting
3288 breakpoints in include files which contain C code. (In the past, you had to
3289 try twice in order to list an include file that you hadn't looked at before.)
3291 * Interesting infernals change
3293 GDB now deals with arbitrary numbers of sections, where the symbols for each
3294 section must be relocated relative to that section's landing place in the
3295 target's address space. This work was needed to support ELF with embedded
3296 stabs used by Solaris-2.0.
3298 * Bug fixes (of course!)
3300 There have been loads of fixes for the following things:
3301 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
3302 i960, stabs, DOS(GO32), procfs, etc...
3304 See the ChangeLog for details.
3306 *** Changes in GDB-4.5:
3308 * New machines supported (host and target)
3310 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
3312 SGI Irix-4.x mips-sgi-irix4 or iris4
3314 * New malloc package
3316 GDB now uses a new memory manager called mmalloc, based on gmalloc.
3317 Mmalloc is capable of handling mutiple heaps of memory. It is also
3318 capable of saving a heap to a file, and then mapping it back in later.
3319 This can be used to greatly speedup the startup of GDB by using a
3320 pre-parsed symbol table which lives in a mmalloc managed heap. For
3321 more details, please read mmalloc/mmalloc.texi.
3325 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
3326 'help info proc' for details.
3328 * MIPS ecoff symbol table format
3330 The code that reads MIPS symbol table format is now supported on all hosts.
3331 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
3334 * File name changes for MS-DOS
3336 Many files in the config directories have been renamed to make it easier to
3337 support GDB on MS-DOSe systems (which have very restrictive file name
3338 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
3339 environment) is close to working but has some remaining problems. Note
3340 that debugging of DOS programs is not supported, due to limitations
3341 in the ``operating system'', but it can be used to host cross-debugging.
3343 * Cross byte order fixes
3345 Many fixes have been made to support cross debugging of Sparc and MIPS
3346 targets from hosts whose byte order differs.
3348 * New -mapped and -readnow options
3350 If memory-mapped files are available on your system through the 'mmap'
3351 system call, you can use the -mapped option on the `file' or
3352 `symbol-file' commands to cause GDB to write the symbols from your
3353 program into a reusable file. If the program you are debugging is
3354 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3355 Future GDB debugging sessions will notice the presence of this file,
3356 and will quickly map in symbol information from it, rather than reading
3357 the symbol table from the executable program. Using the '-mapped'
3358 option in a GDB `file' or `symbol-file' command has the same effect as
3359 starting GDB with the '-mapped' command-line option.
3361 You can cause GDB to read the entire symbol table immediately by using
3362 the '-readnow' option with any of the commands that load symbol table
3363 information (or on the GDB command line). This makes the command
3364 slower, but makes future operations faster.
3366 The -mapped and -readnow options are typically combined in order to
3367 build a `fred.syms' file that contains complete symbol information.
3368 A simple GDB invocation to do nothing but build a `.syms' file for future
3371 gdb -batch -nx -mapped -readnow programname
3373 The `.syms' file is specific to the host machine on which GDB is run.
3374 It holds an exact image of GDB's internal symbol table. It cannot be
3375 shared across multiple host platforms.
3377 * longjmp() handling
3379 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3380 siglongjmp() without losing control. This feature has not yet been ported to
3381 all systems. It currently works on many 386 platforms, all MIPS-based
3382 platforms (SGI, DECstation, etc), and Sun3/4.
3386 Preliminary work has been put in to support the new Solaris OS from Sun. At
3387 this time, it can control and debug processes, but it is not capable of
3392 As always, many many bug fixes. The major areas were with g++, and mipsread.
3393 People using the MIPS-based platforms should experience fewer mysterious
3394 crashes and trashed symbol tables.
3396 *** Changes in GDB-4.4:
3398 * New machines supported (host and target)
3400 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3402 BSD Reno on Vax vax-dec-bsd
3403 Ultrix on Vax vax-dec-ultrix
3405 * New machines supported (target)
3407 AMD 29000 embedded, using EBMON a29k-none-none
3411 GDB continues to improve its handling of C++. `References' work better.
3412 The demangler has also been improved, and now deals with symbols mangled as
3413 per the Annotated C++ Reference Guide.
3415 GDB also now handles `stabs' symbol information embedded in MIPS
3416 `ecoff' symbol tables. Since the ecoff format was not easily
3417 extensible to handle new languages such as C++, this appeared to be a
3418 good way to put C++ debugging info into MIPS binaries. This option
3419 will be supported in the GNU C compiler, version 2, when it is
3422 * New features for SVR4
3424 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3425 shared libraries. Debugging dynamically linked programs should present
3426 only minor differences from debugging statically linked programs.
3428 The `info proc' command will print out information about any process
3429 on an SVR4 system (including the one you are debugging). At the moment,
3430 it prints the address mappings of the process.
3432 If you bring up GDB on another SVR4 system, please send mail to
3433 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3435 * Better dynamic linking support in SunOS
3437 Reading symbols from shared libraries which contain debugging symbols
3438 now works properly. However, there remain issues such as automatic
3439 skipping of `transfer vector' code during function calls, which
3440 make it harder to debug code in a shared library, than to debug the
3441 same code linked statically.
3445 GDB is now using the latest `getopt' routines from the FSF. This
3446 version accepts the -- prefix for options with long names. GDB will
3447 continue to accept the old forms (-option and +option) as well.
3448 Various single letter abbreviations for options have been explicity
3449 added to the option table so that they won't get overshadowed in the
3450 future by other options that begin with the same letter.
3454 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3455 Many assorted bugs have been handled. Many more remain to be handled.
3456 See the various ChangeLog files (primarily in gdb and bfd) for details.
3459 *** Changes in GDB-4.3:
3461 * New machines supported (host and target)
3463 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3464 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3465 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3467 * Almost SCO Unix support
3469 We had hoped to support:
3470 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3471 (except for core file support), but we discovered very late in the release
3472 that it has problems with process groups that render gdb unusable. Sorry
3473 about that. I encourage people to fix it and post the fixes.
3475 * Preliminary ELF and DWARF support
3477 GDB can read ELF object files on System V Release 4, and can handle
3478 debugging records for C, in DWARF format, in ELF files. This support
3479 is preliminary. If you bring up GDB on another SVR4 system, please
3480 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3485 GDB now uses the latest `readline' library. One user-visible change
3486 is that two tabs will list possible command completions, which previously
3487 required typing M-? (meta-question mark, or ESC ?).
3491 The `stepi' bug that many of you noticed has been squashed.
3492 Many bugs in C++ have been handled. Many more remain to be handled.
3493 See the various ChangeLog files (primarily in gdb and bfd) for details.
3495 * State of the MIPS world (in case you wondered):
3497 GDB can understand the symbol tables emitted by the compilers
3498 supplied by most vendors of MIPS-based machines, including DEC. These
3499 symbol tables are in a format that essentially nobody else uses.
3501 Some versions of gcc come with an assembler post-processor called
3502 mips-tfile. This program is required if you want to do source-level
3503 debugging of gcc-compiled programs. I believe FSF does not ship
3504 mips-tfile with gcc version 1, but it will eventually come with gcc
3507 Debugging of g++ output remains a problem. g++ version 1.xx does not
3508 really support it at all. (If you're lucky, you should be able to get
3509 line numbers and stack traces to work, but no parameters or local
3510 variables.) With some work it should be possible to improve the
3513 When gcc version 2 is released, you will have somewhat better luck.
3514 However, even then you will get confusing results for inheritance and
3517 We will eventually provide full debugging of g++ output on
3518 DECstations. This will probably involve some kind of stabs-in-ecoff
3519 encapulation, but the details have not been worked out yet.
3522 *** Changes in GDB-4.2:
3524 * Improved configuration
3526 Only one copy of `configure' exists now, and it is not self-modifying.
3527 Porting BFD is simpler.
3531 The `step' and `next' commands now only stop at the first instruction
3532 of a source line. This prevents the multiple stops that used to occur
3533 in switch statements, for-loops, etc. `Step' continues to stop if a
3534 function that has debugging information is called within the line.
3538 Lots of small bugs fixed. More remain.
3540 * New host supported (not target)
3542 Intel 386 PC clone running Mach i386-none-mach
3545 *** Changes in GDB-4.1:
3547 * Multiple source language support
3549 GDB now has internal scaffolding to handle several source languages.
3550 It determines the type of each source file from its filename extension,
3551 and will switch expression parsing and number formatting to match the
3552 language of the function in the currently selected stack frame.
3553 You can also specifically set the language to be used, with
3554 `set language c' or `set language modula-2'.
3558 GDB now has preliminary support for the GNU Modula-2 compiler,
3559 currently under development at the State University of New York at
3560 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3561 continue through the fall of 1991 and into 1992.
3563 Other Modula-2 compilers are currently not supported, and attempting to
3564 debug programs compiled with them will likely result in an error as the
3565 symbol table is read. Feel free to work on it, though!
3567 There are hooks in GDB for strict type checking and range checking,
3568 in the `Modula-2 philosophy', but they do not currently work.
3572 GDB can now write to executable and core files (e.g. patch
3573 a variable's value). You must turn this switch on, specify
3574 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3575 by assigning a new value to a variable. Modifications take
3578 * Automatic SunOS shared library reading
3580 When you run your program, GDB automatically determines where its
3581 shared libraries (if any) have been loaded, and reads their symbols.
3582 The `share' command is no longer needed. This also works when
3583 examining core files.
3587 You can specify the number of lines that the `list' command shows.
3590 * New machines supported (host and target)
3592 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3593 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3594 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3596 * New hosts supported (not targets)
3598 IBM RT/PC: romp-ibm-aix or rtpc
3600 * New targets supported (not hosts)
3602 AMD 29000 embedded with COFF a29k-none-coff
3603 AMD 29000 embedded with a.out a29k-none-aout
3604 Ultracomputer remote kernel debug a29k-nyu-kern
3606 * New remote interfaces
3612 *** Changes in GDB-4.0:
3616 Wide output is wrapped at good places to make the output more readable.
3618 Gdb now supports cross-debugging from a host machine of one type to a
3619 target machine of another type. Communication with the target system
3620 is over serial lines. The ``target'' command handles connecting to the
3621 remote system; the ``load'' command will download a program into the
3622 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3623 also supports debugging of realtime processes running under VxWorks,
3624 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3625 stub on the target system.
3627 New CPUs supported include the AMD 29000 and Intel 960.
3629 GDB now reads object files and symbol tables via a ``binary file''
3630 library, which allows a single copy of GDB to debug programs of multiple
3631 object file types such as a.out and coff.
3633 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3634 refcard.dvi and refcard.ps are available to format it).
3637 * Control-Variable user interface simplified
3639 All variables that control the operation of the debugger can be set
3640 by the ``set'' command, and displayed by the ``show'' command.
3642 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3643 ``Show prompt'' produces the response:
3644 Gdb's prompt is new-gdb=>.
3646 What follows are the NEW set commands. The command ``help set'' will
3647 print a complete list of old and new set commands. ``help set FOO''
3648 will give a longer description of the variable FOO. ``show'' will show
3649 all of the variable descriptions and their current settings.
3651 confirm on/off: Enables warning questions for operations that are
3652 hard to recover from, e.g. rerunning the program while
3653 it is already running. Default is ON.
3655 editing on/off: Enables EMACS style command line editing
3656 of input. Previous lines can be recalled with
3657 control-P, the current line can be edited with control-B,
3658 you can search for commands with control-R, etc.
3661 history filename NAME: NAME is where the gdb command history
3662 will be stored. The default is .gdb_history,
3663 or the value of the environment variable
3666 history size N: The size, in commands, of the command history. The
3667 default is 256, or the value of the environment variable
3670 history save on/off: If this value is set to ON, the history file will
3671 be saved after exiting gdb. If set to OFF, the
3672 file will not be saved. The default is OFF.
3674 history expansion on/off: If this value is set to ON, then csh-like
3675 history expansion will be performed on
3676 command line input. The default is OFF.
3678 radix N: Sets the default radix for input and output. It can be set
3679 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3680 in the current radix, so "set radix 10" is always a no-op.
3682 height N: This integer value is the number of lines on a page. Default
3683 is 24, the current `stty rows'' setting, or the ``li#''
3684 setting from the termcap entry matching the environment
3687 width N: This integer value is the number of characters on a line.
3688 Default is 80, the current `stty cols'' setting, or the ``co#''
3689 setting from the termcap entry matching the environment
3692 Note: ``set screensize'' is obsolete. Use ``set height'' and
3693 ``set width'' instead.
3695 print address on/off: Print memory addresses in various command displays,
3696 such as stack traces and structure values. Gdb looks
3697 more ``symbolic'' if you turn this off; it looks more
3698 ``machine level'' with it on. Default is ON.
3700 print array on/off: Prettyprint arrays. New convenient format! Default
3703 print demangle on/off: Print C++ symbols in "source" form if on,
3706 print asm-demangle on/off: Same, for assembler level printouts
3709 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3712 * Support for Epoch Environment.
3714 The epoch environment is a version of Emacs v18 with windowing. One
3715 new command, ``inspect'', is identical to ``print'', except that if you
3716 are running in the epoch environment, the value is printed in its own
3720 * Support for Shared Libraries
3722 GDB can now debug programs and core files that use SunOS shared libraries.
3723 Symbols from a shared library cannot be referenced
3724 before the shared library has been linked with the program (this
3725 happens after you type ``run'' and before the function main() is entered).
3726 At any time after this linking (including when examining core files
3727 from dynamically linked programs), gdb reads the symbols from each
3728 shared library when you type the ``sharedlibrary'' command.
3729 It can be abbreviated ``share''.
3731 sharedlibrary REGEXP: Load shared object library symbols for files
3732 matching a unix regular expression. No argument
3733 indicates to load symbols for all shared libraries.
3735 info sharedlibrary: Status of loaded shared libraries.
3740 A watchpoint stops execution of a program whenever the value of an
3741 expression changes. Checking for this slows down execution
3742 tremendously whenever you are in the scope of the expression, but is
3743 quite useful for catching tough ``bit-spreader'' or pointer misuse
3744 problems. Some machines such as the 386 have hardware for doing this
3745 more quickly, and future versions of gdb will use this hardware.
3747 watch EXP: Set a watchpoint (breakpoint) for an expression.
3749 info watchpoints: Information about your watchpoints.
3751 delete N: Deletes watchpoint number N (same as breakpoints).
3752 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3753 enable N: Re-enables watchpoint number N (same as breakpoints).
3756 * C++ multiple inheritance
3758 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3761 * C++ exception handling
3763 Gdb now supports limited C++ exception handling. Besides the existing
3764 ability to breakpoint on an exception handler, gdb can breakpoint on
3765 the raising of an exception (before the stack is peeled back to the
3768 catch FOO: If there is a FOO exception handler in the dynamic scope,
3769 set a breakpoint to catch exceptions which may be raised there.
3770 Multiple exceptions (``catch foo bar baz'') may be caught.
3772 info catch: Lists all exceptions which may be caught in the
3773 current stack frame.
3776 * Minor command changes
3778 The command ``call func (arg, arg, ...)'' now acts like the print
3779 command, except it does not print or save a value if the function's result
3780 is void. This is similar to dbx usage.
3782 The ``up'' and ``down'' commands now always print the frame they end up
3783 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3784 frames without printing.
3786 * New directory command
3788 'dir' now adds directories to the FRONT of the source search path.
3789 The path starts off empty. Source files that contain debug information
3790 about the directory in which they were compiled can be found even
3791 with an empty path; Sun CC and GCC include this information. If GDB can't
3792 find your source file in the current directory, type "dir .".
3794 * Configuring GDB for compilation
3796 For normal use, type ``./configure host''. See README or gdb.texinfo
3799 GDB now handles cross debugging. If you are remotely debugging between
3800 two different machines, type ``./configure host -target=targ''.
3801 Host is the machine where GDB will run; targ is the machine
3802 where the program that you are debugging will run.