1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.6
6 * The GDB remote stub, gdbserver, now has lower overhead for high
7 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
9 * GDB for MIPS targets now autodetects whether a remote target provides
10 32-bit or 64-bit register values.
12 * Support for C++ member pointers has been improved.
16 set mem inaccessible-by-default
17 show mem inaccessible-by-default
18 If the target supplies a memory map, for instance via the remote
19 protocol's "qXfer:memory-map:read" packet, setting this variable
20 prevents GDB from accessing memory outside the memory map. This
21 is useful for targets with memory mapped registers or which react
22 badly to accesses of unmapped address space.
24 set breakpoint auto-hw
25 show breakpoint auto-hw
26 If the target supplies a memory map, for instance via the remote
27 protocol's "qXfer:memory-map:read" packet, setting this variable
28 lets GDB use hardware breakpoints automatically for memory regions
29 where it can not use software breakpoints. This covers both the
30 "break" command and internal breakpoints used for other commands
31 including "next" and "finish".
34 catch exception unhandled
35 Stop the program execution when Ada exceptions are raised.
38 Stop the program execution when an Ada assertion failed.
42 Set an alternate system root for target files. This is a more
43 general version of "set solib-absolute-prefix", which is now
44 an alias to "set sysroot".
46 * New native configurations
48 OpenBSD/sh sh*-*openbsd*
52 OpenBSD/sh sh*-*-openbsd*
53 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
58 Ignore the specified signals; pass them directly to the debugged program
59 without stopping other threads or reporting them to GDB.
62 *** Changes in GDB 6.6
67 Cell Broadband Engine SPU spu-elf
69 * GDB can now be configured as a cross-debugger targeting native Windows
70 (mingw32) or Cygwin. It can communicate with a remote debugging stub
71 running on a Windows system over TCP/IP to debug Windows programs.
73 * The GDB remote stub, gdbserver, has been updated to support Windows and
74 Cygwin debugging. Both single-threaded and multi-threaded programs are
77 * The "set trust-readonly-sections" command works again. This command was
78 broken in GDB 6.3, 6.4, and 6.5.
80 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
81 longer requires symbolic debug information (e.g. DWARF-2).
88 Manage a list of substitution rules that GDB uses to rewrite the name
89 of the directories where the sources are located. This can be useful
90 for instance when the sources were moved to a different location
91 between compilation and debugging.
95 Print each CLI command as it is executed. Each command is prefixed with
96 a number of `+' symbols representing the nesting depth.
97 The source command now has a `-v' option to enable the same feature.
101 The ARM Demon monitor support (RDP protocol, "target rdp").
103 Kernel Object Display, an embedded debugging feature which only worked with
104 an obsolete version of Cisco IOS.
106 The 'set download-write-size' and 'show download-write-size' commands.
111 Tell a stub about GDB client features, and request remote target features.
112 The first feature implemented is PacketSize, which allows the target to
113 specify the size of packets it can handle - to minimize the number of
114 packets required and improve performance when connected to a remote
118 Fetch an OS auxilliary vector from the remote stub. This packet is a
119 more efficient replacement for qPart:auxv:read.
121 * Removed remote packets
124 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
125 used it, and only gdbserver implemented it.
127 *** Changes in GDB 6.5
131 Renesas M32C/M16C m32c-elf
133 Morpho Technologies ms1 ms1-elf
137 init-if-undefined Initialize a convenience variable, but
138 only if it doesn't already have a value.
140 The following commands are presently only implemented for native GNU/Linux:
142 checkpoint Save a snapshot of the program state.
144 restart <n> Return the program state to a
145 previously saved state.
147 info checkpoints List currently saved checkpoints.
149 delete-checkpoint <n> Delete a previously saved checkpoint.
151 set|show detach-on-fork Tell gdb whether to detach from a newly
152 forked process, or to keep debugging it.
154 info forks List forks of the user program that
155 are available to be debugged.
157 fork <n> Switch to debugging one of several
158 forks of the user program that are
159 available to be debugged.
161 delete-fork <n> Delete a fork from the list of forks
162 that are available to be debugged (and
163 kill the forked process).
165 detach-fork <n> Delete a fork from the list of forks
166 that are available to be debugged (and
167 allow the process to continue).
171 Morpho Technologies ms2 ms1-elf
173 * Improved Windows host support
175 GDB now builds as a cross debugger hosted on i686-mingw32, including
176 native console support, and remote communications using either
177 network sockets or serial ports.
179 * Improved Modula-2 language support
181 GDB can now print most types in the Modula-2 syntax. This includes:
182 basic types, set types, record types, enumerated types, range types,
183 pointer types and ARRAY types. Procedure var parameters are correctly
184 printed and hexadecimal addresses and character constants are also
185 written in the Modula-2 syntax. Best results can be obtained by using
186 GNU Modula-2 together with the -gdwarf-2 command line option.
190 The ARM rdi-share module.
192 The Netware NLM debug server.
194 *** Changes in GDB 6.4
196 * New native configurations
198 OpenBSD/arm arm*-*-openbsd*
199 OpenBSD/mips64 mips64-*-openbsd*
203 Morpho Technologies ms1 ms1-elf
205 * New command line options
207 --batch-silent As for --batch, but totally silent.
208 --return-child-result The debugger will exist with the same value
209 the child (debugged) program exited with.
210 --eval-command COMMAND, -ex COMMAND
211 Execute a single GDB CLI command. This may be
212 specified multiple times and in conjunction
213 with the --command (-x) option.
215 * Deprecated commands removed
217 The following commands, that were deprecated in 2000, have been
221 set|show arm disassembly-flavor set|show arm disassembler
222 othernames set arm disassembler
223 set|show remotedebug set|show debug remote
224 set|show archdebug set|show debug arch
225 set|show eventdebug set|show debug event
228 * New BSD user-level threads support
230 It is now possible to debug programs using the user-level threads
231 library on OpenBSD and FreeBSD. Currently supported (target)
234 FreeBSD/amd64 x86_64-*-freebsd*
235 FreeBSD/i386 i386-*-freebsd*
236 OpenBSD/i386 i386-*-openbsd*
238 Note that the new kernel threads libraries introduced in FreeBSD 5.x
239 are not yet supported.
241 * New support for Matsushita MN10300 w/sim added
242 (Work in progress). mn10300-elf.
244 * REMOVED configurations and files
246 VxWorks and the XDR protocol *-*-vxworks
247 Motorola MCORE mcore-*-*
248 National Semiconductor NS32000 ns32k-*-*
250 * New "set print array-indexes" command
252 After turning this setting "on", GDB prints the index of each element
253 when displaying arrays. The default is "off" to preserve the previous
256 * VAX floating point support
258 GDB now supports the not-quite-ieee VAX F and D floating point formats.
260 * User-defined command support
262 In addition to using $arg0..$arg9 for argument passing, it is now possible
263 to use $argc to determine now many arguments have been passed. See the
264 section on user-defined commands in the user manual for more information.
266 *** Changes in GDB 6.3:
268 * New command line option
270 GDB now accepts -l followed by a number to set the timeout for remote
273 * GDB works with GCC -feliminate-dwarf2-dups
275 GDB now supports a more compact representation of DWARF-2 debug
276 information using DW_FORM_ref_addr references. These are produced
277 by GCC with the option -feliminate-dwarf2-dups and also by some
278 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
279 to use -feliminate-dwarf2-dups.
281 * Internationalization
283 When supported by the host system, GDB will be built with
284 internationalization (libintl). The task of marking up the sources is
285 continued, we're looking forward to our first translation.
289 Initial support for debugging programs compiled with the GNAT
290 implementation of the Ada programming language has been integrated
291 into GDB. In this release, support is limited to expression evaluation.
293 * New native configurations
295 GNU/Linux/m32r m32r-*-linux-gnu
299 GDB's remote protocol now includes support for the 'p' packet. This
300 packet is used to fetch individual registers from a remote inferior.
302 * END-OF-LIFE registers[] compatibility module
304 GDB's internal register infrastructure has been completely rewritten.
305 The new infrastructure making possible the implementation of key new
306 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
309 GDB 6.3 will be the last release to include the the registers[]
310 compatibility module that allowed out-of-date configurations to
311 continue to work. This change directly impacts the following
323 Unless there is activity to revive these configurations, they will be
324 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
326 * OBSOLETE configurations and files
328 Configurations that have been declared obsolete in this release have
329 been commented out. Unless there is activity to revive these
330 configurations, the next release of GDB will have their sources
340 *** Changes in GDB 6.2.1:
342 * MIPS `break main; run' gave an heuristic-fence-post warning
344 When attempting to run even a simple program, a warning about
345 heuristic-fence-post being hit would be reported. This problem has
348 * MIPS IRIX 'long double' crashed GDB
350 When examining a long double variable, GDB would get a segmentation
351 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
352 IRIX long double values).
356 A bug in the VAX stack code was causing problems with the "next"
357 command. This problem has been fixed.
359 *** Changes in GDB 6.2:
361 * Fix for ``many threads''
363 On GNU/Linux systems that use the NPTL threads library, a program
364 rapidly creating and deleting threads would confuse GDB leading to the
367 ptrace: No such process.
368 thread_db_get_info: cannot get thread info: generic error
370 This problem has been fixed.
372 * "-async" and "-noasync" options removed.
374 Support for the broken "-noasync" option has been removed (it caused
377 * New ``start'' command.
379 This command runs the program until the begining of the main procedure.
381 * New BSD Kernel Data Access Library (libkvm) interface
383 Using ``target kvm'' it is now possible to debug kernel core dumps and
384 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
385 platforms. Currently supported (native-only) configurations are:
387 FreeBSD/amd64 x86_64-*-freebsd*
388 FreeBSD/i386 i?86-*-freebsd*
389 NetBSD/i386 i?86-*-netbsd*
390 NetBSD/m68k m68*-*-netbsd*
391 NetBSD/sparc sparc-*-netbsd*
392 OpenBSD/amd64 x86_64-*-openbsd*
393 OpenBSD/i386 i?86-*-openbsd*
394 OpenBSD/m68k m68*-openbsd*
395 OpenBSD/sparc sparc-*-openbsd*
397 * Signal trampoline code overhauled
399 Many generic problems with GDB's signal handling code have been fixed.
400 These include: backtraces through non-contiguous stacks; recognition
401 of sa_sigaction signal trampolines; backtrace from a NULL pointer
402 call; backtrace through a signal trampoline; step into and out of
403 signal handlers; and single-stepping in the signal trampoline.
405 Please note that kernel bugs are a limiting factor here. These
406 features have been shown to work on an s390 GNU/Linux system that
407 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
409 * Cygwin support for DWARF 2 added.
411 * New native configurations
413 GNU/Linux/hppa hppa*-*-linux*
414 OpenBSD/hppa hppa*-*-openbsd*
415 OpenBSD/m68k m68*-*-openbsd*
416 OpenBSD/m88k m88*-*-openbsd*
417 OpenBSD/powerpc powerpc-*-openbsd*
418 NetBSD/vax vax-*-netbsd*
419 OpenBSD/vax vax-*-openbsd*
421 * END-OF-LIFE frame compatibility module
423 GDB's internal frame infrastructure has been completely rewritten.
424 The new infrastructure making it possible to support key new features
425 including DWARF 2 Call Frame Information. To aid in the task of
426 migrating old configurations to this new infrastructure, a
427 compatibility module, that allowed old configurations to continue to
428 work, was also included.
430 GDB 6.2 will be the last release to include this frame compatibility
431 module. This change directly impacts the following configurations:
441 Unless there is activity to revive these configurations, they will be
442 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
444 * REMOVED configurations and files
446 Sun 3, running SunOS 3 m68*-*-sunos3*
447 Sun 3, running SunOS 4 m68*-*-sunos4*
448 Sun 2, running SunOS 3 m68000-*-sunos3*
449 Sun 2, running SunOS 4 m68000-*-sunos4*
450 Motorola 680x0 running LynxOS m68*-*-lynxos*
451 AT&T 3b1/Unix pc m68*-att-*
452 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
453 decstation mips-dec-* mips-little-*
454 riscos mips-*-riscos* mips-*-sysv*
456 sysv mips*-*-sysv4* (IRIX 5/6 not included)
458 *** Changes in GDB 6.1.1:
460 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
462 The TUI (Text-mode User Interface) is now built as part of a default
463 GDB configuration. It is enabled by either selecting the TUI with the
464 command line option "-i=tui" or by running the separate "gdbtui"
465 program. For more information on the TUI, see the manual "Debugging
468 * Pending breakpoint support (also included in GDB 6.1)
470 Support has been added to allow you to specify breakpoints in shared
471 libraries that have not yet been loaded. If a breakpoint location
472 cannot be found, and the "breakpoint pending" option is set to auto,
473 GDB queries you if you wish to make the breakpoint pending on a future
474 shared-library load. If and when GDB resolves the breakpoint symbol,
475 the pending breakpoint is removed as one or more regular breakpoints
478 Pending breakpoints are very useful for GCJ Java debugging.
480 * Fixed ISO-C build problems
482 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
483 non ISO-C code that stopped them being built using a more strict ISO-C
484 compiler (e.g., IBM's C compiler).
486 * Fixed build problem on IRIX 5
488 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
489 wasn't able to compile compile on an IRIX 5 system.
491 * Added execute permission to gdb/gdbserver/configure
493 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
494 permission. This bug would cause configure to fail on a number of
495 systems (Solaris, IRIX). Ref: server/519.
497 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
499 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
500 has been updated to use constant array sizes.
502 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
504 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
505 its generated DWARF Call Frame Info. This encoding was causing GDB to
506 panic, that panic has been fixed. Ref: gdb/1628.
508 * Fixed a problem when examining parameters in shared library code.
510 When examining parameters in optimized shared library code generated
511 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
512 not available''. GDB now correctly displays the variable's value.
514 *** Changes in GDB 6.1:
516 * Removed --with-mmalloc
518 Support for the mmalloc memory manager has been removed, as it
519 conflicted with the internal gdb byte cache.
521 * Changes in AMD64 configurations
523 The AMD64 target now includes the %cs and %ss registers. As a result
524 the AMD64 remote protocol has changed; this affects the floating-point
525 and SSE registers. If you rely on those registers for your debugging,
526 you should upgrade gdbserver on the remote side.
528 * Revised SPARC target
530 The SPARC target has been completely revised, incorporating the
531 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
532 support for LynxOS and SunOS 4 has been dropped. Calling functions
533 from within GDB on operating systems with a non-executable stack
534 (Solaris, OpenBSD) now works.
538 GDB has a new C++ demangler which does a better job on the mangled
539 names generated by current versions of g++. It also runs faster, so
540 with this and other changes gdb should now start faster on large C++
543 * DWARF 2 Location Expressions
545 GDB support for location expressions has been extended to support function
546 arguments and frame bases. Older versions of GDB could crash when they
549 * C++ nested types and namespaces
551 GDB's support for nested types and namespaces in C++ has been
552 improved, especially if you use the DWARF 2 debugging format. (This
553 is the default for recent versions of GCC on most platforms.)
554 Specifically, if you have a class "Inner" defined within a class or
555 namespace "Outer", then GDB realizes that the class's name is
556 "Outer::Inner", not simply "Inner". This should greatly reduce the
557 frequency of complaints about not finding RTTI symbols. In addition,
558 if you are stopped at inside of a function defined within a namespace,
559 GDB modifies its name lookup accordingly.
561 * New native configurations
563 NetBSD/amd64 x86_64-*-netbsd*
564 OpenBSD/amd64 x86_64-*-openbsd*
565 OpenBSD/alpha alpha*-*-openbsd*
566 OpenBSD/sparc sparc-*-openbsd*
567 OpenBSD/sparc64 sparc64-*-openbsd*
569 * New debugging protocols
571 M32R with SDI protocol m32r-*-elf*
573 * "set prompt-escape-char" command deleted.
575 The command "set prompt-escape-char" has been deleted. This command,
576 and its very obscure effet on GDB's prompt, was never documented,
577 tested, nor mentioned in the NEWS file.
579 * OBSOLETE configurations and files
581 Configurations that have been declared obsolete in this release have
582 been commented out. Unless there is activity to revive these
583 configurations, the next release of GDB will have their sources
586 Sun 3, running SunOS 3 m68*-*-sunos3*
587 Sun 3, running SunOS 4 m68*-*-sunos4*
588 Sun 2, running SunOS 3 m68000-*-sunos3*
589 Sun 2, running SunOS 4 m68000-*-sunos4*
590 Motorola 680x0 running LynxOS m68*-*-lynxos*
591 AT&T 3b1/Unix pc m68*-att-*
592 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
593 decstation mips-dec-* mips-little-*
594 riscos mips-*-riscos* mips-*-sysv*
596 sysv mips*-*-sysv4* (IRIX 5/6 not included)
598 * REMOVED configurations and files
600 SGI Irix-4.x mips-sgi-irix4 or iris4
601 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
602 Z8000 simulator z8k-zilog-none or z8ksim
603 Matsushita MN10200 w/simulator mn10200-*-*
604 H8/500 simulator h8500-hitachi-hms or h8500hms
605 HP/PA running BSD hppa*-*-bsd*
606 HP/PA running OSF/1 hppa*-*-osf*
607 HP/PA Pro target hppa*-*-pro*
608 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
609 386BSD i[3456]86-*-bsd*
610 Sequent family i[3456]86-sequent-sysv4*
611 i[3456]86-sequent-sysv*
612 i[3456]86-sequent-bsd*
613 SPARC running LynxOS sparc-*-lynxos*
614 SPARC running SunOS 4 sparc-*-sunos4*
615 Tsqware Sparclet sparclet-*-*
616 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
618 *** Changes in GDB 6.0:
622 Support for debugging the Objective-C programming language has been
625 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
627 DWARF 2's Call Frame Information makes available compiler generated
628 information that more exactly describes the program's run-time stack.
629 By using this information, GDB is able to provide more robust stack
632 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
633 have been updated to use a new backtrace mechanism which includes
638 GDB's remote protocol has been extended to include support for hosted
639 file I/O (where the remote target uses GDB's file system). See GDB's
640 remote protocol documentation for details.
642 * All targets using the new architecture framework.
644 All of GDB's targets have been updated to use the new internal
645 architecture framework. The way is now open for future GDB releases
646 to include cross-architecture native debugging support (i386 on amd64,
649 * GNU/Linux's Thread Local Storage (TLS)
651 GDB now includes support for for the GNU/Linux implementation of
652 per-thread variables.
654 * GNU/Linux's Native POSIX Thread Library (NPTL)
656 GDB's thread code has been updated to work with either the new
657 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
659 * Separate debug info.
661 GDB, in conjunction with BINUTILS, now supports a mechanism for
662 automatically loading debug information from a separate file. Instead
663 of shipping full debug and non-debug versions of system libraries,
664 system integrators can now instead ship just the stripped libraries
665 and optional debug files.
667 * DWARF 2 Location Expressions
669 DWARF 2 Location Expressions allow the compiler to more completely
670 describe the location of variables (even in optimized code) to the
673 GDB now includes preliminary support for location expressions (support
674 for DW_OP_piece is still missing).
678 A number of long standing bugs that caused GDB to die while starting a
679 Java application have been fixed. GDB's Java support is now
680 considered "useable".
682 * GNU/Linux support for fork, vfork, and exec.
684 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
685 commands are now implemented for GNU/Linux. They require a 2.5.x or later
688 * GDB supports logging output to a file
690 There are two new commands, "set logging" and "show logging", which can be
691 used to capture GDB's output to a file.
693 * The meaning of "detach" has changed for gdbserver
695 The "detach" command will now resume the application, as documented. To
696 disconnect from gdbserver and leave it stopped, use the new "disconnect"
699 * d10v, m68hc11 `regs' command deprecated
701 The `info registers' command has been updated so that it displays the
702 registers using a format identical to the old `regs' command.
706 A new command, "maint set profile on/off", has been added. This command can
707 be used to enable or disable profiling while running GDB, to profile a
708 session or a set of commands. In addition there is a new configure switch,
709 "--enable-profiling", which will cause GDB to be compiled with profiling
710 data, for more informative profiling results.
712 * Default MI syntax changed to "mi2".
714 The default MI (machine interface) syntax, enabled by the command line
715 option "-i=mi", has been changed to "mi2". The previous MI syntax,
716 "mi1", can be enabled by specifying the option "-i=mi1".
718 Support for the original "mi0" syntax (included in GDB 5.0) has been
721 Fix for gdb/192: removed extraneous space when displaying frame level.
722 Fix for gdb/672: update changelist is now output in mi list format.
723 Fix for gdb/702: a -var-assign that updates the value now shows up
724 in a subsequent -var-update.
726 * New native configurations.
728 FreeBSD/amd64 x86_64-*-freebsd*
730 * Multi-arched targets.
732 HP/PA HPUX11 hppa*-*-hpux*
733 Renesas M32R/D w/simulator m32r-*-elf*
735 * OBSOLETE configurations and files
737 Configurations that have been declared obsolete in this release have
738 been commented out. Unless there is activity to revive these
739 configurations, the next release of GDB will have their sources
742 Z8000 simulator z8k-zilog-none or z8ksim
743 Matsushita MN10200 w/simulator mn10200-*-*
744 H8/500 simulator h8500-hitachi-hms or h8500hms
745 HP/PA running BSD hppa*-*-bsd*
746 HP/PA running OSF/1 hppa*-*-osf*
747 HP/PA Pro target hppa*-*-pro*
748 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
749 Sequent family i[3456]86-sequent-sysv4*
750 i[3456]86-sequent-sysv*
751 i[3456]86-sequent-bsd*
752 Tsqware Sparclet sparclet-*-*
753 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
755 * REMOVED configurations and files
758 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
759 IBM AIX PS/2 i[3456]86-*-aix
760 i386 running Mach 3.0 i[3456]86-*-mach3*
761 i386 running Mach i[3456]86-*-mach*
762 i386 running OSF/1 i[3456]86-*osf1mk*
763 HP/Apollo 68k Family m68*-apollo*-sysv*,
765 m68*-hp-bsd*, m68*-hp-hpux*
766 Argonaut Risc Chip (ARC) arc-*-*
767 Mitsubishi D30V d30v-*-*
768 Fujitsu FR30 fr30-*-elf*
769 OS/9000 i[34]86-*-os9k
770 I960 with MON960 i960-*-coff
772 * MIPS $fp behavior changed
774 The convenience variable $fp, for the MIPS, now consistently returns
775 the address of the current frame's base. Previously, depending on the
776 context, $fp could refer to either $sp or the current frame's base
777 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
778 The GNU Source-Level Debugger''.
780 *** Changes in GDB 5.3:
782 * GNU/Linux shared library multi-threaded performance improved.
784 When debugging a multi-threaded application on GNU/Linux, GDB now uses
785 `/proc', in preference to `ptrace' for memory reads. This may result
786 in an improvement in the start-up time of multi-threaded, shared
787 library applications when run under GDB. One GDB user writes: ``loads
788 shared libs like mad''.
790 * ``gdbserver'' now supports multi-threaded applications on some targets
792 Support for debugging multi-threaded applications which use
793 the GNU/Linux LinuxThreads package has been added for
794 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
795 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
797 * GDB now supports C/C++ preprocessor macros.
799 GDB now expands preprocessor macro invocations in C/C++ expressions,
800 and provides various commands for showing macro definitions and how
803 The new command `macro expand EXPRESSION' expands any macro
804 invocations in expression, and shows the result.
806 The new command `show macro MACRO-NAME' shows the definition of the
807 macro named MACRO-NAME, and where it was defined.
809 Most compilers don't include information about macros in the debugging
810 information by default. In GCC 3.1, for example, you need to compile
811 your program with the options `-gdwarf-2 -g3'. If the macro
812 information is present in the executable, GDB will read it.
814 * Multi-arched targets.
816 DEC Alpha (partial) alpha*-*-*
817 DEC VAX (partial) vax-*-*
819 National Semiconductor NS32000 (partial) ns32k-*-*
820 Motorola 68000 (partial) m68k-*-*
821 Motorola MCORE mcore-*-*
825 Fujitsu FRV architecture added by Red Hat frv*-*-*
828 * New native configurations
830 Alpha NetBSD alpha*-*-netbsd*
831 SH NetBSD sh*-*-netbsdelf*
832 MIPS NetBSD mips*-*-netbsd*
833 UltraSPARC NetBSD sparc64-*-netbsd*
835 * OBSOLETE configurations and files
837 Configurations that have been declared obsolete in this release have
838 been commented out. Unless there is activity to revive these
839 configurations, the next release of GDB will have their sources
842 Mitsubishi D30V d30v-*-*
843 OS/9000 i[34]86-*-os9k
844 IBM AIX PS/2 i[3456]86-*-aix
845 Fujitsu FR30 fr30-*-elf*
846 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
847 Argonaut Risc Chip (ARC) arc-*-*
848 i386 running Mach 3.0 i[3456]86-*-mach3*
849 i386 running Mach i[3456]86-*-mach*
850 i386 running OSF/1 i[3456]86-*osf1mk*
851 HP/Apollo 68k Family m68*-apollo*-sysv*,
853 m68*-hp-bsd*, m68*-hp-hpux*
854 I960 with MON960 i960-*-coff
858 CHILL, a Pascal like language used by telecommunications companies.
860 * REMOVED configurations and files
862 AMD 29k family via UDI a29k-amd-udi, udi29k
863 A29K VxWorks a29k-*-vxworks
864 AMD 29000 embedded, using EBMON a29k-none-none
865 AMD 29000 embedded with COFF a29k-none-coff
866 AMD 29000 embedded with a.out a29k-none-aout
868 testsuite/gdb.hp/gdb.threads-hp/ directory
870 * New command "set max-user-call-depth <nnn>"
872 This command allows the user to limit the call depth of user-defined
873 commands. The default is 1024.
875 * Changes in FreeBSD/i386 native debugging.
877 Support for the "generate-core-file" has been added.
879 * New commands "dump", "append", and "restore".
881 These commands allow data to be copied from target memory
882 to a bfd-format or binary file (dump and append), and back
883 from a file into memory (restore).
885 * Improved "next/step" support on multi-processor Alpha Tru64.
887 The previous single-step mechanism could cause unpredictable problems,
888 including the random appearance of SIGSEGV or SIGTRAP signals. The use
889 of a software single-step mechanism prevents this.
891 *** Changes in GDB 5.2.1:
899 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
900 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
901 Fix, by Joel Brobecker imported from mainline.
903 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
904 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
905 Fix, by Fred Fish, imported from mainline.
907 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
908 Surprisingly enough, it works now.
909 By Michal Ludvig, imported from mainline.
911 i386 hardware watchpoint support:
912 avoid misses on second run for some targets.
913 By Pierre Muller, imported from mainline.
915 *** Changes in GDB 5.2:
917 * New command "set trust-readonly-sections on[off]".
919 This command is a hint that tells gdb that read-only sections
920 really are read-only (ie. that their contents will not change).
921 In this mode, gdb will go to the object file rather than the
922 target to read memory from read-only sections (such as ".text").
923 This can be a significant performance improvement on some
924 (notably embedded) targets.
926 * New command "generate-core-file" (or "gcore").
928 This new gdb command allows the user to drop a core file of the child
929 process state at any time. So far it's been implemented only for
930 GNU/Linux and Solaris, but should be relatively easily ported to other
931 hosts. Argument is core file name (defaults to core.<pid>).
933 * New command line option
935 GDB now accepts --pid or -p followed by a process id.
937 * Change in command line behavior -- corefiles vs. process ids.
939 There is a subtle behavior in the way in which GDB handles
940 command line arguments. The first non-flag argument is always
941 a program to debug, but the second non-flag argument may either
942 be a corefile or a process id. Previously, GDB would attempt to
943 open the second argument as a corefile, and if that failed, would
944 issue a superfluous error message and then attempt to attach it as
945 a process. Now, if the second argument begins with a non-digit,
946 it will be treated as a corefile. If it begins with a digit,
947 GDB will attempt to attach it as a process, and if no such process
948 is found, will then attempt to open it as a corefile.
950 * Changes in ARM configurations.
952 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
953 configuration is fully multi-arch.
955 * New native configurations
957 ARM NetBSD arm*-*-netbsd*
958 x86 OpenBSD i[3456]86-*-openbsd*
959 AMD x86-64 running GNU/Linux x86_64-*-linux-*
960 Sparc64 running FreeBSD sparc64-*-freebsd*
964 Sanyo XStormy16 xstormy16-elf
966 * OBSOLETE configurations and files
968 Configurations that have been declared obsolete in this release have
969 been commented out. Unless there is activity to revive these
970 configurations, the next release of GDB will have their sources
973 AMD 29k family via UDI a29k-amd-udi, udi29k
974 A29K VxWorks a29k-*-vxworks
975 AMD 29000 embedded, using EBMON a29k-none-none
976 AMD 29000 embedded with COFF a29k-none-coff
977 AMD 29000 embedded with a.out a29k-none-aout
979 testsuite/gdb.hp/gdb.threads-hp/ directory
981 * REMOVED configurations and files
983 TI TMS320C80 tic80-*-*
985 PowerPC Solaris powerpcle-*-solaris*
986 PowerPC Windows NT powerpcle-*-cygwin32
987 PowerPC Netware powerpc-*-netware*
988 Harris/CXUX m88k m88*-harris-cxux*
989 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
990 ns32k-utek-sysv* ns32k-utek-*
991 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
992 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
993 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
994 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
995 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
997 * Changes to command line processing
999 The new `--args' feature can be used to specify command-line arguments
1000 for the inferior from gdb's command line.
1002 * Changes to key bindings
1004 There is a new `operate-and-get-next' function bound to `C-o'.
1006 *** Changes in GDB 5.1.1
1008 Fix compile problem on DJGPP.
1010 Fix a problem with floating-point registers on the i386 being
1013 Fix to stop GDB crashing on .debug_str debug info.
1015 Numerous documentation fixes.
1017 Numerous testsuite fixes.
1019 *** Changes in GDB 5.1:
1021 * New native configurations
1023 Alpha FreeBSD alpha*-*-freebsd*
1024 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1025 MIPS GNU/Linux mips*-*-linux*
1026 MIPS SGI Irix 6.x mips*-sgi-irix6*
1027 ia64 AIX ia64-*-aix*
1028 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1032 Motorola 68HC11 and 68HC12 m68hc11-elf
1034 UltraSparc running GNU/Linux sparc64-*-linux*
1036 * OBSOLETE configurations and files
1038 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1039 Harris/CXUX m88k m88*-harris-cxux*
1040 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1041 ns32k-utek-sysv* ns32k-utek-*
1042 TI TMS320C80 tic80-*-*
1044 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1045 PowerPC Solaris powerpcle-*-solaris*
1046 PowerPC Windows NT powerpcle-*-cygwin32
1047 PowerPC Netware powerpc-*-netware*
1048 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1049 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1050 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1051 Apple Macintosh (MPW) host N/A
1053 stuff.c (Program to stuff files into a specially prepared space in kdb)
1054 kdb-start.c (Main loop for the standalone kernel debugger)
1056 Configurations that have been declared obsolete in this release have
1057 been commented out. Unless there is activity to revive these
1058 configurations, the next release of GDB will have their sources
1059 permanently REMOVED.
1061 * REMOVED configurations and files
1063 Altos 3068 m68*-altos-*
1064 Convex c1-*-*, c2-*-*
1066 ARM RISCix arm-*-* (as host)
1070 * GDB has been converted to ISO C.
1072 GDB's source code has been converted to ISO C. In particular, the
1073 sources are fully protoized, and rely on standard headers being
1078 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1080 * The MI enabled by default.
1082 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1083 revised and enabled by default. Packages which use GDB as a debugging
1084 engine behind a UI or another front end are encouraged to switch to
1085 using the GDB/MI interface, instead of the old annotations interface
1086 which is now deprecated.
1088 * Support for debugging Pascal programs.
1090 GDB now includes support for debugging Pascal programs. The following
1091 main features are supported:
1093 - Pascal-specific data types such as sets;
1095 - automatic recognition of Pascal sources based on file-name
1098 - Pascal-style display of data types, variables, and functions;
1100 - a Pascal expression parser.
1102 However, some important features are not yet supported.
1104 - Pascal string operations are not supported at all;
1106 - there are some problems with boolean types;
1108 - Pascal type hexadecimal constants are not supported
1109 because they conflict with the internal variables format;
1111 - support for Pascal objects and classes is not full yet;
1113 - unlike Pascal, GDB is case-sensitive for symbol names.
1115 * Changes in completion.
1117 Commands such as `shell', `run' and `set args', which pass arguments
1118 to inferior programs, now complete on file names, similar to what
1119 users expect at the shell prompt.
1121 Commands which accept locations, such as `disassemble', `print',
1122 `breakpoint', `until', etc. now complete on filenames as well as
1123 program symbols. Thus, if you type "break foob TAB", and the source
1124 files linked into the programs include `foobar.c', that file name will
1125 be one of the candidates for completion. However, file names are not
1126 considered for completion after you typed a colon that delimits a file
1127 name from a name of a function in that file, as in "break foo.c:bar".
1129 `set demangle-style' completes on available demangling styles.
1131 * New platform-independent commands:
1133 It is now possible to define a post-hook for a command as well as a
1134 hook that runs before the command. For more details, see the
1135 documentation of `hookpost' in the GDB manual.
1137 * Changes in GNU/Linux native debugging.
1139 Support for debugging multi-threaded programs has been completely
1140 revised for all platforms except m68k and sparc. You can now debug as
1141 many threads as your system allows you to have.
1143 Attach/detach is supported for multi-threaded programs.
1145 Support for SSE registers was added for x86. This doesn't work for
1146 multi-threaded programs though.
1148 * Changes in MIPS configurations.
1150 Multi-arch support is enabled for all MIPS configurations.
1152 GDB can now be built as native debugger on SGI Irix 6.x systems for
1153 debugging n32 executables. (Debugging 64-bit executables is not yet
1156 * Unified support for hardware watchpoints in all x86 configurations.
1158 Most (if not all) native x86 configurations support hardware-assisted
1159 breakpoints and watchpoints in a unified manner. This support
1160 implements debug register sharing between watchpoints, which allows to
1161 put a virtually infinite number of watchpoints on the same address,
1162 and also supports watching regions up to 16 bytes with several debug
1165 The new maintenance command `maintenance show-debug-regs' toggles
1166 debugging print-outs in functions that insert, remove, and test
1167 watchpoints and hardware breakpoints.
1169 * Changes in the DJGPP native configuration.
1171 New command ``info dos sysinfo'' displays assorted information about
1172 the CPU, OS, memory, and DPMI server.
1174 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1175 display information about segment descriptors stored in GDT, LDT, and
1178 New commands ``info dos pde'' and ``info dos pte'' display entries
1179 from Page Directory and Page Tables (for now works with CWSDPMI only).
1180 New command ``info dos address-pte'' displays the Page Table entry for
1181 a given linear address.
1183 GDB can now pass command lines longer than 126 characters to the
1184 program being debugged (requires an update to the libdbg.a library
1185 which is part of the DJGPP development kit).
1187 DWARF2 debug info is now supported.
1189 It is now possible to `step' and `next' through calls to `longjmp'.
1191 * Changes in documentation.
1193 All GDB documentation was converted to GFDL, the GNU Free
1194 Documentation License.
1196 Tracepoints-related commands are now fully documented in the GDB
1199 TUI, the Text-mode User Interface, is now documented in the manual.
1201 Tracepoints-related commands are now fully documented in the GDB
1204 The "GDB Internals" manual now has an index. It also includes
1205 documentation of `ui_out' functions, GDB coding standards, x86
1206 hardware watchpoints, and memory region attributes.
1208 * GDB's version number moved to ``version.in''
1210 The Makefile variable VERSION has been replaced by the file
1211 ``version.in''. People creating GDB distributions should update the
1212 contents of this file.
1216 GUD support is now a standard part of the EMACS distribution.
1218 *** Changes in GDB 5.0:
1220 * Improved support for debugging FP programs on x86 targets
1222 Unified and much-improved support for debugging floating-point
1223 programs on all x86 targets. In particular, ``info float'' now
1224 displays the FP registers in the same format on all x86 targets, with
1225 greater level of detail.
1227 * Improvements and bugfixes in hardware-assisted watchpoints
1229 It is now possible to watch array elements, struct members, and
1230 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1231 on x86 targets no longer erroneously trigger when the address is
1234 * Improvements in the native DJGPP version of GDB
1236 The distribution now includes all the scripts and auxiliary files
1237 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1238 machines ``out of the box''.
1240 The DJGPP version can now debug programs that use signals. It is
1241 possible to catch signals that happened in the debuggee, deliver
1242 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1243 would kill the program being debugged.) Programs that hook hardware
1244 interrupts (keyboard, timer, etc.) can also be debugged.
1246 It is now possible to debug DJGPP programs that redirect their
1247 standard handles or switch them to raw (as opposed to cooked) mode, or
1248 even close them. The command ``run < foo > bar'' works as expected,
1249 and ``info terminal'' reports useful information about the debuggee's
1250 terminal, including raw/cooked mode, redirection, etc.
1252 The DJGPP version now uses termios functions for console I/O, which
1253 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1256 DOS-style file names with drive letters are now fully supported by
1259 It is now possible to debug DJGPP programs that switch their working
1260 directory. It is also possible to rerun the debuggee any number of
1261 times without restarting GDB; thus, you can use the same setup,
1262 breakpoints, etc. for many debugging sessions.
1264 * New native configurations
1266 ARM GNU/Linux arm*-*-linux*
1267 PowerPC GNU/Linux powerpc-*-linux*
1271 Motorola MCore mcore-*-*
1272 x86 VxWorks i[3456]86-*-vxworks*
1273 PowerPC VxWorks powerpc-*-vxworks*
1274 TI TMS320C80 tic80-*-*
1276 * OBSOLETE configurations
1278 Altos 3068 m68*-altos-*
1279 Convex c1-*-*, c2-*-*
1281 ARM RISCix arm-*-* (as host)
1284 Configurations that have been declared obsolete will be commented out,
1285 but the code will be left in place. If there is no activity to revive
1286 these configurations before the next release of GDB, the sources will
1287 be permanently REMOVED.
1289 * Gould support removed
1291 Support for the Gould PowerNode and NP1 has been removed.
1293 * New features for SVR4
1295 On SVR4 native platforms (such as Solaris), if you attach to a process
1296 without first loading a symbol file, GDB will now attempt to locate and
1297 load symbols from the running process's executable file.
1299 * Many C++ enhancements
1301 C++ support has been greatly improved. Overload resolution now works properly
1302 in almost all cases. RTTI support is on the way.
1304 * Remote targets can connect to a sub-program
1306 A popen(3) style serial-device has been added. This device starts a
1307 sub-process (such as a stand-alone simulator) and then communicates
1308 with that. The sub-program to run is specified using the syntax
1309 ``|<program> <args>'' vis:
1311 (gdb) set remotedebug 1
1312 (gdb) target extended-remote |mn10300-elf-sim program-args
1314 * MIPS 64 remote protocol
1316 A long standing bug in the mips64 remote protocol where by GDB
1317 expected certain 32 bit registers (ex SR) to be transfered as 32
1318 instead of 64 bits has been fixed.
1320 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1321 added to provide backward compatibility with older versions of GDB.
1323 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1325 The command ``set remotebinarydownload'' command has been replaced by
1326 ``set remote X-packet''. Other commands in ``set remote'' family
1327 include ``set remote P-packet''.
1329 * Breakpoint commands accept ranges.
1331 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1332 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1333 ``tracepoint passcount'' also accepts a range of tracepoints.
1335 * ``apropos'' command added.
1337 The ``apropos'' command searches through command names and
1338 documentation strings, printing out matches, making it much easier to
1339 try to find a command that does what you are looking for.
1343 A new machine oriented interface (MI) has been added to GDB. This
1344 interface is designed for debug environments running GDB as a separate
1345 process. This is part of the long term libGDB project. See the
1346 "GDB/MI" chapter of the GDB manual for further information. It can be
1347 enabled by configuring with:
1349 .../configure --enable-gdbmi
1351 *** Changes in GDB-4.18:
1353 * New native configurations
1355 HP-UX 10.20 hppa*-*-hpux10.20
1356 HP-UX 11.x hppa*-*-hpux11.0*
1357 M68K GNU/Linux m68*-*-linux*
1361 Fujitsu FR30 fr30-*-elf*
1362 Intel StrongARM strongarm-*-*
1363 Mitsubishi D30V d30v-*-*
1365 * OBSOLETE configurations
1367 Gould PowerNode, NP1 np1-*-*, pn-*-*
1369 Configurations that have been declared obsolete will be commented out,
1370 but the code will be left in place. If there is no activity to revive
1371 these configurations before the next release of GDB, the sources will
1372 be permanently REMOVED.
1376 As a compatibility experiment, GDB's source files buildsym.h and
1377 buildsym.c have been converted to pure standard C, no longer
1378 containing any K&R compatibility code. We believe that all systems in
1379 use today either come with a standard C compiler, or have a GCC port
1380 available. If this is not true, please report the affected
1381 configuration to bug-gdb@gnu.org immediately. See the README file for
1382 information about getting a standard C compiler if you don't have one
1387 GDB now uses readline 2.2.
1389 * set extension-language
1391 You can now control the mapping between filename extensions and source
1392 languages by using the `set extension-language' command. For instance,
1393 you can ask GDB to treat .c files as C++ by saying
1394 set extension-language .c c++
1395 The command `info extensions' lists all of the recognized extensions
1396 and their associated languages.
1398 * Setting processor type for PowerPC and RS/6000
1400 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1401 you can use the `set processor' command to specify what variant of the
1402 PowerPC family you are debugging. The command
1406 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
1407 following PowerPC and RS6000 variants:
1409 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
1410 rs6000 IBM RS6000 ("POWER") architecture, user-level view
1412 403GC IBM PowerPC 403GC
1413 505 Motorola PowerPC 505
1414 860 Motorola PowerPC 860 or 850
1415 601 Motorola PowerPC 601
1416 602 Motorola PowerPC 602
1417 603 Motorola/IBM PowerPC 603 or 603e
1418 604 Motorola PowerPC 604 or 604e
1419 750 Motorola/IBM PowerPC 750 or 750
1421 At the moment, this command just tells GDB what to name the
1422 special-purpose processor registers. Since almost all the affected
1423 registers are inaccessible to user-level programs, this command is
1424 only useful for remote debugging in its present form.
1428 Thanks to a major code donation from Hewlett-Packard, GDB now has much
1429 more extensive support for HP-UX. Added features include shared
1430 library support, kernel threads and hardware watchpoints for 11.00,
1431 support for HP's ANSI C and C++ compilers, and a compatibility mode
1432 for xdb and dbx commands.
1436 HP's donation includes the new concept of catchpoints, which is a
1437 generalization of the old catch command. On HP-UX, it is now possible
1438 to catch exec, fork, and vfork, as well as library loading.
1440 This means that the existing catch command has changed; its first
1441 argument now specifies the type of catch to be set up. See the
1442 output of "help catch" for a list of catchpoint types.
1444 * Debugging across forks
1446 On HP-UX, you can choose which process to debug when a fork() happens
1451 HP has donated a curses-based terminal user interface (TUI). To get
1452 it, build with --enable-tui. Although this can be enabled for any
1453 configuration, at present it only works for native HP debugging.
1455 * GDB remote protocol additions
1457 A new protocol packet 'X' that writes binary data is now available.
1458 Default behavior is to try 'X', then drop back to 'M' if the stub
1459 fails to respond. The settable variable `remotebinarydownload'
1460 allows explicit control over the use of 'X'.
1462 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1463 full 64-bit address. The command
1465 set remoteaddresssize 32
1467 can be used to revert to the old behaviour. For existing remote stubs
1468 the change should not be noticed, as the additional address information
1471 In order to assist in debugging stubs, you may use the maintenance
1472 command `packet' to send any text string to the stub. For instance,
1474 maint packet heythere
1476 sends the packet "$heythere#<checksum>". Note that it is very easy to
1477 disrupt a debugging session by sending the wrong packet at the wrong
1480 The compare-sections command allows you to compare section data on the
1481 target to what is in the executable file without uploading or
1482 downloading, by comparing CRC checksums.
1484 * Tracing can collect general expressions
1486 You may now collect general expressions at tracepoints. This requires
1487 further additions to the target-side stub; see tracepoint.c and
1488 doc/agentexpr.texi for further details.
1490 * mask-address variable for Mips
1492 For Mips targets, you may control the zeroing of the upper 32 bits of
1493 a 64-bit address by entering `set mask-address on'. This is mainly
1494 of interest to users of embedded R4xxx and R5xxx processors.
1496 * Higher serial baud rates
1498 GDB's serial code now allows you to specify baud rates 57600, 115200,
1499 230400, and 460800 baud. (Note that your host system may not be able
1500 to achieve all of these rates.)
1504 The i960 configuration now includes an initial implementation of a
1505 builtin simulator, contributed by Jim Wilson.
1508 *** Changes in GDB-4.17:
1510 * New native configurations
1512 Alpha GNU/Linux alpha*-*-linux*
1513 Unixware 2.x i[3456]86-unixware2*
1514 Irix 6.x mips*-sgi-irix6*
1515 PowerPC GNU/Linux powerpc-*-linux*
1516 PowerPC Solaris powerpcle-*-solaris*
1517 Sparc GNU/Linux sparc-*-linux*
1518 Motorola sysV68 R3V7.1 m68k-motorola-sysv
1522 Argonaut Risc Chip (ARC) arc-*-*
1523 Hitachi H8/300S h8300*-*-*
1524 Matsushita MN10200 w/simulator mn10200-*-*
1525 Matsushita MN10300 w/simulator mn10300-*-*
1526 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1527 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1528 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1529 Mitsubishi D10V w/simulator d10v-*-*
1530 Mitsubishi M32R/D w/simulator m32r-*-elf*
1531 Tsqware Sparclet sparclet-*-*
1532 NEC V850 w/simulator v850-*-*
1534 * New debugging protocols
1536 ARM with RDI protocol arm*-*-*
1537 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1538 DDB and LSI variants of PMON protocol mips*-*-*
1539 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1540 PowerPC with SDS protocol powerpc{,le}-*-eabi
1541 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1545 All configurations can now understand and use the DWARF 2 debugging
1546 format. The choice is automatic, if the symbol file contains DWARF 2
1551 GDB now includes basic Java language support. This support is
1552 only useful with Java compilers that produce native machine code.
1554 * solib-absolute-prefix and solib-search-path
1556 For SunOS and SVR4 shared libraries, you may now set the prefix for
1557 loading absolute shared library symbol files, and the search path for
1558 locating non-absolute shared library symbol files.
1560 * Live range splitting
1562 GDB can now effectively debug code for which GCC has performed live
1563 range splitting as part of its optimization. See gdb/doc/LRS for
1564 more details on the expected format of the stabs information.
1568 GDB's support for the GNU Hurd, including thread debugging, has been
1569 updated to work with current versions of the Hurd.
1573 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1574 instruction set. ARM GDB automatically detects when Thumb
1575 instructions are in use, and adjusts disassembly and backtracing
1580 GDB's MIPS target configurations now handle the MIP16 16-bit
1585 GDB now includes support for overlays; if an executable has been
1586 linked such that multiple sections are based at the same address, GDB
1587 will decide which section to use for symbolic info. You can choose to
1588 control the decision manually, using overlay commands, or implement
1589 additional target-side support and use "overlay load-target" to bring
1590 in the overlay mapping. Do "help overlay" for more detail.
1594 The command "info symbol <address>" displays information about
1595 the symbol at the specified address.
1599 The standard remote protocol now includes an extension that allows
1600 asynchronous collection and display of trace data. This requires
1601 extensive support in the target-side debugging stub. Tracing mode
1602 includes a new interaction mode in GDB and new commands: see the
1603 file tracepoint.c for more details.
1607 Configurations for embedded MIPS now include a simulator contributed
1608 by Cygnus Solutions. The simulator supports the instruction sets
1609 of most MIPS variants.
1613 Sparc configurations may now include the ERC32 simulator contributed
1614 by the European Space Agency. The simulator is not built into
1615 Sparc targets by default; configure with --enable-sim to include it.
1619 For target configurations that may include multiple variants of a
1620 basic architecture (such as MIPS and SH), you may now set the
1621 architecture explicitly. "set arch" sets, "info arch" lists
1622 the possible architectures.
1624 *** Changes in GDB-4.16:
1626 * New native configurations
1628 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1629 M68K NetBSD m68k-*-netbsd*
1630 PowerPC AIX 4.x powerpc-*-aix*
1631 PowerPC MacOS powerpc-*-macos*
1632 PowerPC Windows NT powerpcle-*-cygwin32
1633 RS/6000 AIX 4.x rs6000-*-aix4*
1637 ARM with RDP protocol arm-*-*
1638 I960 with MON960 i960-*-coff
1639 MIPS VxWorks mips*-*-vxworks*
1640 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1641 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1643 Matra Sparclet sparclet-*-*
1647 The powerpc-eabi configuration now includes the PSIM simulator,
1648 contributed by Andrew Cagney, with assistance from Mike Meissner.
1649 PSIM is a very elaborate model of the PowerPC, including not only
1650 basic instruction set execution, but also details of execution unit
1651 performance and I/O hardware. See sim/ppc/README for more details.
1655 GDB now works with Solaris 2.5.
1657 * Windows 95/NT native
1659 GDB will now work as a native debugger on Windows 95 and Windows NT.
1660 To build it from source, you must use the "gnu-win32" environment,
1661 which uses a DLL to emulate enough of Unix to run the GNU tools.
1662 Further information, binaries, and sources are available at
1663 ftp.cygnus.com, under pub/gnu-win32.
1665 * dont-repeat command
1667 If a user-defined command includes the command `dont-repeat', then the
1668 command will not be repeated if the user just types return. This is
1669 useful if the command is time-consuming to run, so that accidental
1670 extra keystrokes don't run the same command many times.
1672 * Send break instead of ^C
1674 The standard remote protocol now includes an option to send a break
1675 rather than a ^C to the target in order to interrupt it. By default,
1676 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1678 * Remote protocol timeout
1680 The standard remote protocol includes a new variable `remotetimeout'
1681 that allows you to set the number of seconds before GDB gives up trying
1682 to read from the target. The default value is 2.
1684 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1686 By default GDB will automatically keep track of objects as they are
1687 loaded and unloaded by the dynamic linker. By using the command `set
1688 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1689 when shared library events occur, thus allowing you to set breakpoints
1690 in shared libraries which are explicitly loaded by the inferior.
1692 Note this feature does not work on hpux8. On hpux9 you must link
1693 /usr/lib/end.o into your program. This feature should work
1694 automatically on hpux10.
1696 * Irix 5.x hardware watchpoint support
1698 Irix 5 configurations now support the use of hardware watchpoints.
1700 * Mips protocol "SYN garbage limit"
1702 When debugging a Mips target using the `target mips' protocol, you
1703 may set the number of characters that GDB will ignore by setting
1704 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1705 every character. The default value is 1050.
1707 * Recording and replaying remote debug sessions
1709 If you set `remotelogfile' to the name of a file, gdb will write to it
1710 a recording of a remote debug session. This recording may then be
1711 replayed back to gdb using "gdbreplay". See gdbserver/README for
1712 details. This is useful when you have a problem with GDB while doing
1713 remote debugging; you can make a recording of the session and send it
1714 to someone else, who can then recreate the problem.
1716 * Speedups for remote debugging
1718 GDB includes speedups for downloading and stepping MIPS systems using
1719 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1720 and more efficient S-record downloading.
1722 * Memory use reductions and statistics collection
1724 GDB now uses less memory and reports statistics about memory usage.
1725 Try the `maint print statistics' command, for example.
1727 *** Changes in GDB-4.15:
1729 * Psymtabs for XCOFF
1731 The symbol reader for AIX GDB now uses partial symbol tables. This
1732 can greatly improve startup time, especially for large executables.
1734 * Remote targets use caching
1736 Remote targets now use a data cache to speed up communication with the
1737 remote side. The data cache could lead to incorrect results because
1738 it doesn't know about volatile variables, thus making it impossible to
1739 debug targets which use memory mapped I/O devices. `set remotecache
1740 off' turns the the data cache off.
1742 * Remote targets may have threads
1744 The standard remote protocol now includes support for multiple threads
1745 in the target system, using new protocol commands 'H' and 'T'. See
1746 gdb/remote.c for details.
1750 If GDB is configured with `--enable-netrom', then it will include
1751 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1752 acts as though it is a bank of ROM on the target board, but you can
1753 write into it over the network. GDB's support consists only of
1754 support for fast loading into the emulated ROM; to debug, you must use
1755 another protocol, such as standard remote protocol. The usual
1756 sequence is something like
1758 target nrom <netrom-hostname>
1760 target remote <netrom-hostname>:1235
1764 GDB now includes support for the Apple Macintosh, as a host only. It
1765 may be run as either an MPW tool or as a standalone application, and
1766 it can debug through the serial port. All the usual GDB commands are
1767 available, but to the target command, you must supply "serial" as the
1768 device type instead of "/dev/ttyXX". See mpw-README in the main
1769 directory for more information on how to build. The MPW configuration
1770 scripts */mpw-config.in support only a few targets, and only the
1771 mips-idt-ecoff target has been tested.
1775 GDB configuration now uses autoconf. This is not user-visible,
1776 but does simplify configuration and building.
1780 GDB now supports hpux10.
1782 *** Changes in GDB-4.14:
1784 * New native configurations
1786 x86 FreeBSD i[345]86-*-freebsd
1787 x86 NetBSD i[345]86-*-netbsd
1788 NS32k NetBSD ns32k-*-netbsd
1789 Sparc NetBSD sparc-*-netbsd
1793 A29K VxWorks a29k-*-vxworks
1794 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1795 CPU32 EST-300 emulator m68*-*-est*
1796 PowerPC ELF powerpc-*-elf
1799 * Alpha OSF/1 support for procfs
1801 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1802 possible to attach to running processes. As the mounting of the /proc
1803 filesystem is optional on the Alpha, GDB automatically determines
1804 the availability of /proc during startup. This can lead to problems
1805 if /proc is unmounted after GDB has been started.
1807 * Arguments to user-defined commands
1809 User commands may accept up to 10 arguments separated by whitespace.
1810 Arguments are accessed within the user command via $arg0..$arg9. A
1813 print $arg0 + $arg1 + $arg2
1815 To execute the command use:
1818 Defines the command "adder" which prints the sum of its three arguments.
1819 Note the arguments are text substitutions, so they may reference variables,
1820 use complex expressions, or even perform inferior function calls.
1822 * New `if' and `while' commands
1824 This makes it possible to write more sophisticated user-defined
1825 commands. Both commands take a single argument, which is the
1826 expression to evaluate, and must be followed by the commands to
1827 execute, one per line, if the expression is nonzero, the list being
1828 terminated by the word `end'. The `if' command list may include an
1829 `else' word, which causes the following commands to be executed only
1830 if the expression is zero.
1832 * Fortran source language mode
1834 GDB now includes partial support for Fortran 77. It will recognize
1835 Fortran programs and can evaluate a subset of Fortran expressions, but
1836 variables and functions may not be handled correctly. GDB will work
1837 with G77, but does not yet know much about symbols emitted by other
1840 * Better HPUX support
1842 Most debugging facilities now work on dynamic executables for HPPAs
1843 running hpux9 or later. You can attach to running dynamically linked
1844 processes, but by default the dynamic libraries will be read-only, so
1845 for instance you won't be able to put breakpoints in them. To change
1846 that behavior do the following before running the program:
1852 This will cause the libraries to be mapped private and read-write.
1853 To revert to the normal behavior, do this:
1859 You cannot set breakpoints or examine data in the library until after
1860 the library is loaded if the function/data symbols do not have
1863 GDB can now also read debug symbols produced by the HP C compiler on
1864 HPPAs (sorry, no C++, Fortran or 68k support).
1866 * Target byte order now dynamically selectable
1868 You can choose which byte order to use with a target system, via the
1869 commands "set endian big" and "set endian little", and you can see the
1870 current setting by using "show endian". You can also give the command
1871 "set endian auto", in which case GDB will use the byte order
1872 associated with the executable. Currently, only embedded MIPS
1873 configurations support dynamic selection of target byte order.
1875 * New DOS host serial code
1877 This version uses DPMI interrupts to handle buffered I/O, so you
1878 no longer need to run asynctsr when debugging boards connected to
1881 *** Changes in GDB-4.13:
1883 * New "complete" command
1885 This lists all the possible completions for the rest of the line, if it
1886 were to be given as a command itself. This is intended for use by emacs.
1888 * Trailing space optional in prompt
1890 "set prompt" no longer adds a space for you after the prompt you set. This
1891 allows you to set a prompt which ends in a space or one that does not.
1893 * Breakpoint hit counts
1895 "info break" now displays a count of the number of times the breakpoint
1896 has been hit. This is especially useful in conjunction with "ignore"; you
1897 can ignore a large number of breakpoint hits, look at the breakpoint info
1898 to see how many times the breakpoint was hit, then run again, ignoring one
1899 less than that number, and this will get you quickly to the last hit of
1902 * Ability to stop printing at NULL character
1904 "set print null-stop" will cause GDB to stop printing the characters of
1905 an array when the first NULL is encountered. This is useful when large
1906 arrays actually contain only short strings.
1908 * Shared library breakpoints
1910 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1911 breakpoints in shared libraries before the executable is run.
1913 * Hardware watchpoints
1915 There is a new hardware breakpoint for the watch command for sparclite
1916 targets. See gdb/sparclite/hw_breakpoint.note.
1918 Hardware watchpoints are also now supported under GNU/Linux.
1922 Annotations have been added. These are for use with graphical interfaces,
1923 and are still experimental. Currently only gdba.el uses these.
1925 * Improved Irix 5 support
1927 GDB now works properly with Irix 5.2.
1929 * Improved HPPA support
1931 GDB now works properly with the latest GCC and GAS.
1933 * New native configurations
1935 Sequent PTX4 i[34]86-sequent-ptx4
1936 HPPA running OSF/1 hppa*-*-osf*
1937 Atari TT running SVR4 m68*-*-sysv4*
1938 RS/6000 LynxOS rs6000-*-lynxos*
1942 OS/9000 i[34]86-*-os9k
1943 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1946 * Hitachi SH7000 and E7000-PC ICE support
1948 There is now support for communicating with the Hitachi E7000-PC ICE.
1949 This is available automatically when GDB is configured for the SH.
1953 As usual, a variety of small fixes and improvements, both generic
1954 and configuration-specific. See the ChangeLog for more detail.
1956 *** Changes in GDB-4.12:
1958 * Irix 5 is now supported
1962 GDB-4.12 on the HPPA has a number of changes which make it unable
1963 to debug the output from the currently released versions of GCC and
1964 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1965 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1966 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1969 *** Changes in GDB-4.11:
1971 * User visible changes:
1975 The "set remotedebug" option is now consistent between the mips remote
1976 target, remote targets using the gdb-specific protocol, UDI (AMD's
1977 debug protocol for the 29k) and the 88k bug monitor. It is now an
1978 integer specifying a debug level (normally 0 or 1, but 2 means more
1979 debugging info for the mips target).
1981 * DEC Alpha native support
1983 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1984 debug info, but GDB works fairly well with the DEC compiler and should
1985 work with a future GCC release. See the README file for a few
1986 Alpha-specific notes.
1988 * Preliminary thread implementation
1990 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1992 * LynxOS native and target support for 386
1994 This release has been hosted on LynxOS 2.2, and also can be configured
1995 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1998 * Improvements in C++ mangling/demangling.
2000 This release has much better g++ debugging, specifically in name
2001 mangling/demangling, virtual function calls, print virtual table,
2002 call methods, ...etc.
2004 *** Changes in GDB-4.10:
2006 * User visible changes:
2008 Remote debugging using the GDB-specific (`target remote') protocol now
2009 supports the `load' command. This is only useful if you have some
2010 other way of getting the stub to the target system, and you can put it
2011 somewhere in memory where it won't get clobbered by the download.
2013 Filename completion now works.
2015 When run under emacs mode, the "info line" command now causes the
2016 arrow to point to the line specified. Also, "info line" prints
2017 addresses in symbolic form (as well as hex).
2019 All vxworks based targets now support a user settable option, called
2020 vxworks-timeout. This option represents the number of seconds gdb
2021 should wait for responses to rpc's. You might want to use this if
2022 your vxworks target is, perhaps, a slow software simulator or happens
2023 to be on the far side of a thin network line.
2027 This release contains support for using a DEC alpha as a GDB host for
2028 cross debugging. Native alpha debugging is not supported yet.
2031 *** Changes in GDB-4.9:
2035 This is the first GDB release which is accompanied by a matching testsuite.
2036 The testsuite requires installation of dejagnu, which should be available
2037 via ftp from most sites that carry GNU software.
2041 'Cfront' style demangling has had its name changed to 'ARM' style, to
2042 emphasize that it was written from the specifications in the C++ Annotated
2043 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2044 disclaimers, it still generated too much confusion with users attempting to
2045 use gdb with AT&T cfront.
2049 GDB now uses a standard remote interface to a simulator library.
2050 So far, the library contains simulators for the Zilog Z8001/2, the
2051 Hitachi H8/300, H8/500 and Super-H.
2053 * New targets supported
2055 H8/300 simulator h8300-hitachi-hms or h8300hms
2056 H8/500 simulator h8500-hitachi-hms or h8500hms
2057 SH simulator sh-hitachi-hms or sh
2058 Z8000 simulator z8k-zilog-none or z8ksim
2059 IDT MIPS board over serial line mips-idt-ecoff
2061 Cross-debugging to GO32 targets is supported. It requires a custom
2062 version of the i386-stub.c module which is integrated with the
2063 GO32 memory extender.
2065 * New remote protocols
2067 MIPS remote debugging protocol.
2069 * New source languages supported
2071 This version includes preliminary support for Chill, a Pascal like language
2072 used by telecommunications companies. Chill support is also being integrated
2073 into the GNU compiler, but we don't know when it will be publically available.
2076 *** Changes in GDB-4.8:
2078 * HP Precision Architecture supported
2080 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2081 version of this support was available as a set of patches from the
2082 University of Utah. GDB does not support debugging of programs
2083 compiled with the HP compiler, because HP will not document their file
2084 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2085 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2087 Many problems in the preliminary version have been fixed.
2089 * Faster and better demangling
2091 We have improved template demangling and fixed numerous bugs in the GNU style
2092 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2093 character types (wchar_t) are now supported. Demangling of each symbol is now
2094 only done once, and is cached when the symbol table for a file is read in.
2095 This results in a small increase in memory usage for C programs, a moderate
2096 increase in memory usage for C++ programs, and a fantastic speedup in
2099 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2100 from the specifications in the Annotated Reference Manual, which AT&T's
2101 compiler does not actually implement.
2103 * G++ multiple inheritance compiler problem
2105 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2106 inheritance lattices was reworked to properly discover ambiguities. We
2107 recently found an example which causes this new algorithm to fail in a
2108 very subtle way, producing bad debug information for those classes.
2109 The file 'gcc.patch' (in this directory) can be applied to gcc to
2110 circumvent the problem. A future GCC release will contain a complete
2113 The previous G++ debug info problem (mentioned below for the gdb-4.7
2114 release) is fixed in gcc version 2.3.2.
2116 * Improved configure script
2118 The `configure' script will now attempt to guess your system type if
2119 you don't supply a host system type. The old scheme of supplying a
2120 host system triplet is preferable over using this. All the magic is
2121 done in the new `config.guess' script. Examine it for details.
2123 We have also brought our configure script much more in line with the FSF's
2124 version. It now supports the --with-xxx options. In particular,
2125 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2126 The resulting GDB will not be able to read arbitrary object file formats --
2127 only the format ``expected'' to be used on the configured target system.
2128 We hope to make this the default in a future release.
2130 * Documentation improvements
2132 There's new internal documentation on how to modify GDB, and how to
2133 produce clean changes to the code. We implore people to read it
2134 before submitting changes.
2136 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2137 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2138 `info' files are also provided. To build `info' files from scratch,
2139 you will need the latest `makeinfo' release, which will be available in
2140 a future texinfo-X.Y release.
2142 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2143 We're not sure exactly which versions have this problem, but it has
2144 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2145 or better. If that isn't possible, there is a patch in
2146 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2147 around this problem.
2151 GDB now supports array constants that can be used in expressions typed in by
2152 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2153 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2156 The new directory `gdb/sparclite' contains a program that demonstrates
2157 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2159 * New native hosts supported
2161 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2162 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2164 * New targets supported
2166 AMD 29k family via UDI a29k-amd-udi or udi29k
2168 * New file formats supported
2170 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2171 HPUX core files, and SCO 3.2v2 core files.
2175 Attaching to processes now works again; thanks for the many bug reports.
2177 We have also stomped on a bunch of core dumps caused by
2178 printf_filtered("%s") problems.
2180 We eliminated a copyright problem on the rpc and ptrace header files
2181 for VxWorks, which was discovered at the last minute during the 4.7
2182 release. You should now be able to build a VxWorks GDB.
2184 You can now interrupt gdb while an attached process is running. This
2185 will cause the attached process to stop, and give control back to GDB.
2187 We fixed problems caused by using too many file descriptors
2188 for reading symbols from object files and libraries. This was
2189 especially a problem for programs that used many (~100) shared
2192 The `step' command now only enters a subroutine if there is line number
2193 information for the subroutine. Otherwise it acts like the `next'
2194 command. Previously, `step' would enter subroutines if there was
2195 any debugging information about the routine. This avoids problems
2196 when using `cc -g1' on MIPS machines.
2198 * Internal improvements
2200 GDB's internal interfaces have been improved to make it easier to support
2201 debugging of multiple languages in the future.
2203 GDB now uses a common structure for symbol information internally.
2204 Minimal symbols (derived from linkage symbols in object files), partial
2205 symbols (from a quick scan of debug information), and full symbols
2206 contain a common subset of information, making it easier to write
2207 shared code that handles any of them.
2209 * New command line options
2211 We now accept --silent as an alias for --quiet.
2215 The memory-mapped-malloc library is now licensed under the GNU Library
2216 General Public License.
2218 *** Changes in GDB-4.7:
2220 * Host/native/target split
2222 GDB has had some major internal surgery to untangle the support for
2223 hosts and remote targets. Now, when you configure GDB for a remote
2224 target, it will no longer load in all of the support for debugging
2225 local programs on the host. When fully completed and tested, this will
2226 ensure that arbitrary host/target combinations are possible.
2228 The primary conceptual shift is to separate the non-portable code in
2229 GDB into three categories. Host specific code is required any time GDB
2230 is compiled on that host, regardless of the target. Target specific
2231 code relates to the peculiarities of the target, but can be compiled on
2232 any host. Native specific code is everything else: it can only be
2233 built when the host and target are the same system. Child process
2234 handling and core file support are two common `native' examples.
2236 GDB's use of /proc for controlling Unix child processes is now cleaner.
2237 It has been split out into a single module under the `target_ops' vector,
2238 plus two native-dependent functions for each system that uses /proc.
2240 * New hosts supported
2242 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2243 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2244 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2246 * New targets supported
2248 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2249 68030 and CPU32 m68030-*-*, m68332-*-*
2251 * New native hosts supported
2253 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2254 (386bsd is not well tested yet)
2255 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2257 * New file formats supported
2259 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2260 supports reading of `a.out.adobe' object files, which are an a.out
2261 format extended with minimal information about multiple sections.
2265 `show copying' is the same as the old `info copying'.
2266 `show warranty' is the same as `info warrantee'.
2267 These were renamed for consistency. The old commands continue to work.
2269 `info handle' is a new alias for `info signals'.
2271 You can now define pre-command hooks, which attach arbitrary command
2272 scripts to any command. The commands in the hook will be executed
2273 prior to the user's command. You can also create a hook which will be
2274 executed whenever the program stops. See gdb.texinfo.
2278 We now deal with Cfront style name mangling, and can even extract type
2279 info from mangled symbols. GDB can automatically figure out which
2280 symbol mangling style your C++ compiler uses.
2282 Calling of methods and virtual functions has been improved as well.
2286 The crash that occured when debugging Sun Ansi-C compiled binaries is
2287 fixed. This was due to mishandling of the extra N_SO stabs output
2290 We also finally got Ultrix 4.2 running in house, and fixed core file
2291 support, with help from a dozen people on the net.
2293 John M. Farrell discovered that the reason that single-stepping was so
2294 slow on all of the Mips based platforms (primarily SGI and DEC) was
2295 that we were trying to demangle and lookup a symbol used for internal
2296 purposes on every instruction that was being stepped through. Changing
2297 the name of that symbol so that it couldn't be mistaken for a C++
2298 mangled symbol sped things up a great deal.
2300 Rich Pixley sped up symbol lookups in general by getting much smarter
2301 about when C++ symbol mangling is necessary. This should make symbol
2302 completion (TAB on the command line) much faster. It's not as fast as
2303 we'd like, but it's significantly faster than gdb-4.6.
2307 A new user controllable variable 'call_scratch_address' can
2308 specify the location of a scratch area to be used when GDB
2309 calls a function in the target. This is necessary because the
2310 usual method of putting the scratch area on the stack does not work
2311 in systems that have separate instruction and data spaces.
2313 We integrated changes to support the 29k UDI (Universal Debugger
2314 Interface), but discovered at the last minute that we didn't have all
2315 of the appropriate copyright paperwork. We are working with AMD to
2316 resolve this, and hope to have it available soon.
2320 We have sped up the remote serial line protocol, especially for targets
2321 with lots of registers. It now supports a new `expedited status' ('T')
2322 message which can be used in place of the existing 'S' status message.
2323 This allows the remote stub to send only the registers that GDB
2324 needs to make a quick decision about single-stepping or conditional
2325 breakpoints, eliminating the need to fetch the entire register set for
2326 each instruction being stepped through.
2328 The GDB remote serial protocol now implements a write-through cache for
2329 registers, only re-reading the registers if the target has run.
2331 There is also a new remote serial stub for SPARC processors. You can
2332 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2333 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2334 processor with a serial port.
2338 Configure.in files have become much easier to read and modify. A new
2339 `table driven' format makes it more obvious what configurations are
2340 supported, and what files each one uses.
2344 There is a new opcodes library which will eventually contain all of the
2345 disassembly routines and opcode tables. At present, it only contains
2346 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2347 disassembler (binutils/objdump) to share these routines.
2349 The libiberty library is now copylefted under the GNU Library General
2350 Public License. This allows more liberal use, and was done so libg++
2351 can use it. This makes no difference to GDB, since the Library License
2352 grants all the rights from the General Public License.
2356 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2357 reference to the stabs symbol info used by the debugger. It is (as far
2358 as we know) the only published document on this fascinating topic. We
2359 encourage you to read it, compare it to the stabs information on your
2360 system, and send improvements on the document in general (to
2361 bug-gdb@prep.ai.mit.edu).
2363 And, of course, many bugs have been fixed.
2366 *** Changes in GDB-4.6:
2368 * Better support for C++ function names
2370 GDB now accepts as input the "demangled form" of C++ overloaded function
2371 names and member function names, and can do command completion on such names
2372 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2373 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2374 Make use of command completion, it is your friend.
2376 GDB also now accepts a variety of C++ mangled symbol formats. They are
2377 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2378 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2379 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2380 for the list of formats.
2382 * G++ symbol mangling problem
2384 Recent versions of gcc have a bug in how they emit debugging information for
2385 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2386 directory) can be applied to gcc to fix the problem. Alternatively, if you
2387 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2388 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2389 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2392 * New 'maintenance' command
2394 All of the commands related to hacking GDB internals have been moved out of
2395 the main command set, and now live behind the 'maintenance' command. This
2396 can also be abbreviated as 'mt'. The following changes were made:
2398 dump-me -> maintenance dump-me
2399 info all-breakpoints -> maintenance info breakpoints
2400 printmsyms -> maintenance print msyms
2401 printobjfiles -> maintenance print objfiles
2402 printpsyms -> maintenance print psymbols
2403 printsyms -> maintenance print symbols
2405 The following commands are new:
2407 maintenance demangle Call internal GDB demangler routine to
2408 demangle a C++ link name and prints the result.
2409 maintenance print type Print a type chain for a given symbol
2411 * Change to .gdbinit file processing
2413 We now read the $HOME/.gdbinit file before processing the argv arguments
2414 (e.g. reading symbol files or core files). This allows global parameters to
2415 be set, which will apply during the symbol reading. The ./.gdbinit is still
2416 read after argv processing.
2418 * New hosts supported
2420 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
2422 GNU/Linux support i386-unknown-linux or linux
2424 We are also including code to support the HP/PA running BSD and HPUX. This
2425 is almost guaranteed not to work, as we didn't have time to test or build it
2426 for this release. We are including it so that the more adventurous (or
2427 masochistic) of you can play with it. We also had major problems with the
2428 fact that the compiler that we got from HP doesn't support the -g option.
2431 * New targets supported
2433 Hitachi H8/300 h8300-hitachi-hms or h8300hms
2435 * More smarts about finding #include files
2437 GDB now remembers the compilation directory for all include files, and for
2438 all files from which C is generated (like yacc and lex sources). This
2439 greatly improves GDB's ability to find yacc/lex sources, and include files,
2440 especially if you are debugging your program from a directory different from
2441 the one that contains your sources.
2443 We also fixed a bug which caused difficulty with listing and setting
2444 breakpoints in include files which contain C code. (In the past, you had to
2445 try twice in order to list an include file that you hadn't looked at before.)
2447 * Interesting infernals change
2449 GDB now deals with arbitrary numbers of sections, where the symbols for each
2450 section must be relocated relative to that section's landing place in the
2451 target's address space. This work was needed to support ELF with embedded
2452 stabs used by Solaris-2.0.
2454 * Bug fixes (of course!)
2456 There have been loads of fixes for the following things:
2457 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2458 i960, stabs, DOS(GO32), procfs, etc...
2460 See the ChangeLog for details.
2462 *** Changes in GDB-4.5:
2464 * New machines supported (host and target)
2466 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2468 SGI Irix-4.x mips-sgi-irix4 or iris4
2470 * New malloc package
2472 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2473 Mmalloc is capable of handling mutiple heaps of memory. It is also
2474 capable of saving a heap to a file, and then mapping it back in later.
2475 This can be used to greatly speedup the startup of GDB by using a
2476 pre-parsed symbol table which lives in a mmalloc managed heap. For
2477 more details, please read mmalloc/mmalloc.texi.
2481 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2482 'help info proc' for details.
2484 * MIPS ecoff symbol table format
2486 The code that reads MIPS symbol table format is now supported on all hosts.
2487 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2490 * File name changes for MS-DOS
2492 Many files in the config directories have been renamed to make it easier to
2493 support GDB on MS-DOSe systems (which have very restrictive file name
2494 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2495 environment) is close to working but has some remaining problems. Note
2496 that debugging of DOS programs is not supported, due to limitations
2497 in the ``operating system'', but it can be used to host cross-debugging.
2499 * Cross byte order fixes
2501 Many fixes have been made to support cross debugging of Sparc and MIPS
2502 targets from hosts whose byte order differs.
2504 * New -mapped and -readnow options
2506 If memory-mapped files are available on your system through the 'mmap'
2507 system call, you can use the -mapped option on the `file' or
2508 `symbol-file' commands to cause GDB to write the symbols from your
2509 program into a reusable file. If the program you are debugging is
2510 called `/path/fred', the mapped symbol file will be `./fred.syms'.
2511 Future GDB debugging sessions will notice the presence of this file,
2512 and will quickly map in symbol information from it, rather than reading
2513 the symbol table from the executable program. Using the '-mapped'
2514 option in a GDB `file' or `symbol-file' command has the same effect as
2515 starting GDB with the '-mapped' command-line option.
2517 You can cause GDB to read the entire symbol table immediately by using
2518 the '-readnow' option with any of the commands that load symbol table
2519 information (or on the GDB command line). This makes the command
2520 slower, but makes future operations faster.
2522 The -mapped and -readnow options are typically combined in order to
2523 build a `fred.syms' file that contains complete symbol information.
2524 A simple GDB invocation to do nothing but build a `.syms' file for future
2527 gdb -batch -nx -mapped -readnow programname
2529 The `.syms' file is specific to the host machine on which GDB is run.
2530 It holds an exact image of GDB's internal symbol table. It cannot be
2531 shared across multiple host platforms.
2533 * longjmp() handling
2535 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2536 siglongjmp() without losing control. This feature has not yet been ported to
2537 all systems. It currently works on many 386 platforms, all MIPS-based
2538 platforms (SGI, DECstation, etc), and Sun3/4.
2542 Preliminary work has been put in to support the new Solaris OS from Sun. At
2543 this time, it can control and debug processes, but it is not capable of
2548 As always, many many bug fixes. The major areas were with g++, and mipsread.
2549 People using the MIPS-based platforms should experience fewer mysterious
2550 crashes and trashed symbol tables.
2552 *** Changes in GDB-4.4:
2554 * New machines supported (host and target)
2556 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2558 BSD Reno on Vax vax-dec-bsd
2559 Ultrix on Vax vax-dec-ultrix
2561 * New machines supported (target)
2563 AMD 29000 embedded, using EBMON a29k-none-none
2567 GDB continues to improve its handling of C++. `References' work better.
2568 The demangler has also been improved, and now deals with symbols mangled as
2569 per the Annotated C++ Reference Guide.
2571 GDB also now handles `stabs' symbol information embedded in MIPS
2572 `ecoff' symbol tables. Since the ecoff format was not easily
2573 extensible to handle new languages such as C++, this appeared to be a
2574 good way to put C++ debugging info into MIPS binaries. This option
2575 will be supported in the GNU C compiler, version 2, when it is
2578 * New features for SVR4
2580 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2581 shared libraries. Debugging dynamically linked programs should present
2582 only minor differences from debugging statically linked programs.
2584 The `info proc' command will print out information about any process
2585 on an SVR4 system (including the one you are debugging). At the moment,
2586 it prints the address mappings of the process.
2588 If you bring up GDB on another SVR4 system, please send mail to
2589 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2591 * Better dynamic linking support in SunOS
2593 Reading symbols from shared libraries which contain debugging symbols
2594 now works properly. However, there remain issues such as automatic
2595 skipping of `transfer vector' code during function calls, which
2596 make it harder to debug code in a shared library, than to debug the
2597 same code linked statically.
2601 GDB is now using the latest `getopt' routines from the FSF. This
2602 version accepts the -- prefix for options with long names. GDB will
2603 continue to accept the old forms (-option and +option) as well.
2604 Various single letter abbreviations for options have been explicity
2605 added to the option table so that they won't get overshadowed in the
2606 future by other options that begin with the same letter.
2610 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2611 Many assorted bugs have been handled. Many more remain to be handled.
2612 See the various ChangeLog files (primarily in gdb and bfd) for details.
2615 *** Changes in GDB-4.3:
2617 * New machines supported (host and target)
2619 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2620 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2621 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2623 * Almost SCO Unix support
2625 We had hoped to support:
2626 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2627 (except for core file support), but we discovered very late in the release
2628 that it has problems with process groups that render gdb unusable. Sorry
2629 about that. I encourage people to fix it and post the fixes.
2631 * Preliminary ELF and DWARF support
2633 GDB can read ELF object files on System V Release 4, and can handle
2634 debugging records for C, in DWARF format, in ELF files. This support
2635 is preliminary. If you bring up GDB on another SVR4 system, please
2636 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2641 GDB now uses the latest `readline' library. One user-visible change
2642 is that two tabs will list possible command completions, which previously
2643 required typing M-? (meta-question mark, or ESC ?).
2647 The `stepi' bug that many of you noticed has been squashed.
2648 Many bugs in C++ have been handled. Many more remain to be handled.
2649 See the various ChangeLog files (primarily in gdb and bfd) for details.
2651 * State of the MIPS world (in case you wondered):
2653 GDB can understand the symbol tables emitted by the compilers
2654 supplied by most vendors of MIPS-based machines, including DEC. These
2655 symbol tables are in a format that essentially nobody else uses.
2657 Some versions of gcc come with an assembler post-processor called
2658 mips-tfile. This program is required if you want to do source-level
2659 debugging of gcc-compiled programs. I believe FSF does not ship
2660 mips-tfile with gcc version 1, but it will eventually come with gcc
2663 Debugging of g++ output remains a problem. g++ version 1.xx does not
2664 really support it at all. (If you're lucky, you should be able to get
2665 line numbers and stack traces to work, but no parameters or local
2666 variables.) With some work it should be possible to improve the
2669 When gcc version 2 is released, you will have somewhat better luck.
2670 However, even then you will get confusing results for inheritance and
2673 We will eventually provide full debugging of g++ output on
2674 DECstations. This will probably involve some kind of stabs-in-ecoff
2675 encapulation, but the details have not been worked out yet.
2678 *** Changes in GDB-4.2:
2680 * Improved configuration
2682 Only one copy of `configure' exists now, and it is not self-modifying.
2683 Porting BFD is simpler.
2687 The `step' and `next' commands now only stop at the first instruction
2688 of a source line. This prevents the multiple stops that used to occur
2689 in switch statements, for-loops, etc. `Step' continues to stop if a
2690 function that has debugging information is called within the line.
2694 Lots of small bugs fixed. More remain.
2696 * New host supported (not target)
2698 Intel 386 PC clone running Mach i386-none-mach
2701 *** Changes in GDB-4.1:
2703 * Multiple source language support
2705 GDB now has internal scaffolding to handle several source languages.
2706 It determines the type of each source file from its filename extension,
2707 and will switch expression parsing and number formatting to match the
2708 language of the function in the currently selected stack frame.
2709 You can also specifically set the language to be used, with
2710 `set language c' or `set language modula-2'.
2714 GDB now has preliminary support for the GNU Modula-2 compiler,
2715 currently under development at the State University of New York at
2716 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2717 continue through the fall of 1991 and into 1992.
2719 Other Modula-2 compilers are currently not supported, and attempting to
2720 debug programs compiled with them will likely result in an error as the
2721 symbol table is read. Feel free to work on it, though!
2723 There are hooks in GDB for strict type checking and range checking,
2724 in the `Modula-2 philosophy', but they do not currently work.
2728 GDB can now write to executable and core files (e.g. patch
2729 a variable's value). You must turn this switch on, specify
2730 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2731 by assigning a new value to a variable. Modifications take
2734 * Automatic SunOS shared library reading
2736 When you run your program, GDB automatically determines where its
2737 shared libraries (if any) have been loaded, and reads their symbols.
2738 The `share' command is no longer needed. This also works when
2739 examining core files.
2743 You can specify the number of lines that the `list' command shows.
2746 * New machines supported (host and target)
2748 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2749 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2750 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2752 * New hosts supported (not targets)
2754 IBM RT/PC: romp-ibm-aix or rtpc
2756 * New targets supported (not hosts)
2758 AMD 29000 embedded with COFF a29k-none-coff
2759 AMD 29000 embedded with a.out a29k-none-aout
2760 Ultracomputer remote kernel debug a29k-nyu-kern
2762 * New remote interfaces
2768 *** Changes in GDB-4.0:
2772 Wide output is wrapped at good places to make the output more readable.
2774 Gdb now supports cross-debugging from a host machine of one type to a
2775 target machine of another type. Communication with the target system
2776 is over serial lines. The ``target'' command handles connecting to the
2777 remote system; the ``load'' command will download a program into the
2778 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2779 also supports debugging of realtime processes running under VxWorks,
2780 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2781 stub on the target system.
2783 New CPUs supported include the AMD 29000 and Intel 960.
2785 GDB now reads object files and symbol tables via a ``binary file''
2786 library, which allows a single copy of GDB to debug programs of multiple
2787 object file types such as a.out and coff.
2789 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2790 refcard.dvi and refcard.ps are available to format it).
2793 * Control-Variable user interface simplified
2795 All variables that control the operation of the debugger can be set
2796 by the ``set'' command, and displayed by the ``show'' command.
2798 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2799 ``Show prompt'' produces the response:
2800 Gdb's prompt is new-gdb=>.
2802 What follows are the NEW set commands. The command ``help set'' will
2803 print a complete list of old and new set commands. ``help set FOO''
2804 will give a longer description of the variable FOO. ``show'' will show
2805 all of the variable descriptions and their current settings.
2807 confirm on/off: Enables warning questions for operations that are
2808 hard to recover from, e.g. rerunning the program while
2809 it is already running. Default is ON.
2811 editing on/off: Enables EMACS style command line editing
2812 of input. Previous lines can be recalled with
2813 control-P, the current line can be edited with control-B,
2814 you can search for commands with control-R, etc.
2817 history filename NAME: NAME is where the gdb command history
2818 will be stored. The default is .gdb_history,
2819 or the value of the environment variable
2822 history size N: The size, in commands, of the command history. The
2823 default is 256, or the value of the environment variable
2826 history save on/off: If this value is set to ON, the history file will
2827 be saved after exiting gdb. If set to OFF, the
2828 file will not be saved. The default is OFF.
2830 history expansion on/off: If this value is set to ON, then csh-like
2831 history expansion will be performed on
2832 command line input. The default is OFF.
2834 radix N: Sets the default radix for input and output. It can be set
2835 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2836 in the current radix, so "set radix 10" is always a no-op.
2838 height N: This integer value is the number of lines on a page. Default
2839 is 24, the current `stty rows'' setting, or the ``li#''
2840 setting from the termcap entry matching the environment
2843 width N: This integer value is the number of characters on a line.
2844 Default is 80, the current `stty cols'' setting, or the ``co#''
2845 setting from the termcap entry matching the environment
2848 Note: ``set screensize'' is obsolete. Use ``set height'' and
2849 ``set width'' instead.
2851 print address on/off: Print memory addresses in various command displays,
2852 such as stack traces and structure values. Gdb looks
2853 more ``symbolic'' if you turn this off; it looks more
2854 ``machine level'' with it on. Default is ON.
2856 print array on/off: Prettyprint arrays. New convenient format! Default
2859 print demangle on/off: Print C++ symbols in "source" form if on,
2862 print asm-demangle on/off: Same, for assembler level printouts
2865 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2868 * Support for Epoch Environment.
2870 The epoch environment is a version of Emacs v18 with windowing. One
2871 new command, ``inspect'', is identical to ``print'', except that if you
2872 are running in the epoch environment, the value is printed in its own
2876 * Support for Shared Libraries
2878 GDB can now debug programs and core files that use SunOS shared libraries.
2879 Symbols from a shared library cannot be referenced
2880 before the shared library has been linked with the program (this
2881 happens after you type ``run'' and before the function main() is entered).
2882 At any time after this linking (including when examining core files
2883 from dynamically linked programs), gdb reads the symbols from each
2884 shared library when you type the ``sharedlibrary'' command.
2885 It can be abbreviated ``share''.
2887 sharedlibrary REGEXP: Load shared object library symbols for files
2888 matching a unix regular expression. No argument
2889 indicates to load symbols for all shared libraries.
2891 info sharedlibrary: Status of loaded shared libraries.
2896 A watchpoint stops execution of a program whenever the value of an
2897 expression changes. Checking for this slows down execution
2898 tremendously whenever you are in the scope of the expression, but is
2899 quite useful for catching tough ``bit-spreader'' or pointer misuse
2900 problems. Some machines such as the 386 have hardware for doing this
2901 more quickly, and future versions of gdb will use this hardware.
2903 watch EXP: Set a watchpoint (breakpoint) for an expression.
2905 info watchpoints: Information about your watchpoints.
2907 delete N: Deletes watchpoint number N (same as breakpoints).
2908 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2909 enable N: Re-enables watchpoint number N (same as breakpoints).
2912 * C++ multiple inheritance
2914 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2917 * C++ exception handling
2919 Gdb now supports limited C++ exception handling. Besides the existing
2920 ability to breakpoint on an exception handler, gdb can breakpoint on
2921 the raising of an exception (before the stack is peeled back to the
2924 catch FOO: If there is a FOO exception handler in the dynamic scope,
2925 set a breakpoint to catch exceptions which may be raised there.
2926 Multiple exceptions (``catch foo bar baz'') may be caught.
2928 info catch: Lists all exceptions which may be caught in the
2929 current stack frame.
2932 * Minor command changes
2934 The command ``call func (arg, arg, ...)'' now acts like the print
2935 command, except it does not print or save a value if the function's result
2936 is void. This is similar to dbx usage.
2938 The ``up'' and ``down'' commands now always print the frame they end up
2939 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2940 frames without printing.
2942 * New directory command
2944 'dir' now adds directories to the FRONT of the source search path.
2945 The path starts off empty. Source files that contain debug information
2946 about the directory in which they were compiled can be found even
2947 with an empty path; Sun CC and GCC include this information. If GDB can't
2948 find your source file in the current directory, type "dir .".
2950 * Configuring GDB for compilation
2952 For normal use, type ``./configure host''. See README or gdb.texinfo
2955 GDB now handles cross debugging. If you are remotely debugging between
2956 two different machines, type ``./configure host -target=targ''.
2957 Host is the machine where GDB will run; targ is the machine
2958 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob