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.
14 * GDB now understands XML target descriptions, which specify the
15 target's overall architecture. GDB can read a description from
16 a local file or over the remote serial protocol.
20 set mem inaccessible-by-default
21 show mem inaccessible-by-default
22 If the target supplies a memory map, for instance via the remote
23 protocol's "qXfer:memory-map:read" packet, setting this variable
24 prevents GDB from accessing memory outside the memory map. This
25 is useful for targets with memory mapped registers or which react
26 badly to accesses of unmapped address space.
28 set breakpoint auto-hw
29 show breakpoint auto-hw
30 If the target supplies a memory map, for instance via the remote
31 protocol's "qXfer:memory-map:read" packet, setting this variable
32 lets GDB use hardware breakpoints automatically for memory regions
33 where it can not use software breakpoints. This covers both the
34 "break" command and internal breakpoints used for other commands
35 including "next" and "finish".
38 catch exception unhandled
39 Stop the program execution when Ada exceptions are raised.
42 Stop the program execution when an Ada assertion failed.
46 Set an alternate system root for target files. This is a more
47 general version of "set solib-absolute-prefix", which is now
48 an alias to "set sysroot".
50 * New native configurations
52 OpenBSD/sh sh*-*openbsd*
57 Use the specified local file as an XML target description, and do
58 not query the target for its built-in description.
62 OpenBSD/sh sh*-*-openbsd*
63 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
68 Ignore the specified signals; pass them directly to the debugged program
69 without stopping other threads or reporting them to GDB.
72 Read an XML target description from the target, which describes its
75 *** Changes in GDB 6.6
80 Cell Broadband Engine SPU spu-elf
82 * GDB can now be configured as a cross-debugger targeting native Windows
83 (mingw32) or Cygwin. It can communicate with a remote debugging stub
84 running on a Windows system over TCP/IP to debug Windows programs.
86 * The GDB remote stub, gdbserver, has been updated to support Windows and
87 Cygwin debugging. Both single-threaded and multi-threaded programs are
90 * The "set trust-readonly-sections" command works again. This command was
91 broken in GDB 6.3, 6.4, and 6.5.
93 * The "load" command now supports writing to flash memory, if the remote
94 stub provides the required support.
96 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
97 longer requires symbolic debug information (e.g. DWARF-2).
102 unset substitute-path
104 Manage a list of substitution rules that GDB uses to rewrite the name
105 of the directories where the sources are located. This can be useful
106 for instance when the sources were moved to a different location
107 between compilation and debugging.
111 Print each CLI command as it is executed. Each command is prefixed with
112 a number of `+' symbols representing the nesting depth.
113 The source command now has a `-v' option to enable the same feature.
117 The ARM Demon monitor support (RDP protocol, "target rdp").
119 Kernel Object Display, an embedded debugging feature which only worked with
120 an obsolete version of Cisco IOS.
122 The 'set download-write-size' and 'show download-write-size' commands.
127 Tell a stub about GDB client features, and request remote target features.
128 The first feature implemented is PacketSize, which allows the target to
129 specify the size of packets it can handle - to minimize the number of
130 packets required and improve performance when connected to a remote
134 Fetch an OS auxilliary vector from the remote stub. This packet is a
135 more efficient replacement for qPart:auxv:read.
137 qXfer:memory-map:read:
138 Fetch a memory map from the remote stub, including information about
139 RAM, ROM, and flash memory devices.
144 Erase and program a flash memory device.
146 * Removed remote packets
149 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
150 used it, and only gdbserver implemented it.
152 *** Changes in GDB 6.5
156 Renesas M32C/M16C m32c-elf
158 Morpho Technologies ms1 ms1-elf
162 init-if-undefined Initialize a convenience variable, but
163 only if it doesn't already have a value.
165 The following commands are presently only implemented for native GNU/Linux:
167 checkpoint Save a snapshot of the program state.
169 restart <n> Return the program state to a
170 previously saved state.
172 info checkpoints List currently saved checkpoints.
174 delete-checkpoint <n> Delete a previously saved checkpoint.
176 set|show detach-on-fork Tell gdb whether to detach from a newly
177 forked process, or to keep debugging it.
179 info forks List forks of the user program that
180 are available to be debugged.
182 fork <n> Switch to debugging one of several
183 forks of the user program that are
184 available to be debugged.
186 delete-fork <n> Delete a fork from the list of forks
187 that are available to be debugged (and
188 kill the forked process).
190 detach-fork <n> Delete a fork from the list of forks
191 that are available to be debugged (and
192 allow the process to continue).
196 Morpho Technologies ms2 ms1-elf
198 * Improved Windows host support
200 GDB now builds as a cross debugger hosted on i686-mingw32, including
201 native console support, and remote communications using either
202 network sockets or serial ports.
204 * Improved Modula-2 language support
206 GDB can now print most types in the Modula-2 syntax. This includes:
207 basic types, set types, record types, enumerated types, range types,
208 pointer types and ARRAY types. Procedure var parameters are correctly
209 printed and hexadecimal addresses and character constants are also
210 written in the Modula-2 syntax. Best results can be obtained by using
211 GNU Modula-2 together with the -gdwarf-2 command line option.
215 The ARM rdi-share module.
217 The Netware NLM debug server.
219 *** Changes in GDB 6.4
221 * New native configurations
223 OpenBSD/arm arm*-*-openbsd*
224 OpenBSD/mips64 mips64-*-openbsd*
228 Morpho Technologies ms1 ms1-elf
230 * New command line options
232 --batch-silent As for --batch, but totally silent.
233 --return-child-result The debugger will exist with the same value
234 the child (debugged) program exited with.
235 --eval-command COMMAND, -ex COMMAND
236 Execute a single GDB CLI command. This may be
237 specified multiple times and in conjunction
238 with the --command (-x) option.
240 * Deprecated commands removed
242 The following commands, that were deprecated in 2000, have been
246 set|show arm disassembly-flavor set|show arm disassembler
247 othernames set arm disassembler
248 set|show remotedebug set|show debug remote
249 set|show archdebug set|show debug arch
250 set|show eventdebug set|show debug event
253 * New BSD user-level threads support
255 It is now possible to debug programs using the user-level threads
256 library on OpenBSD and FreeBSD. Currently supported (target)
259 FreeBSD/amd64 x86_64-*-freebsd*
260 FreeBSD/i386 i386-*-freebsd*
261 OpenBSD/i386 i386-*-openbsd*
263 Note that the new kernel threads libraries introduced in FreeBSD 5.x
264 are not yet supported.
266 * New support for Matsushita MN10300 w/sim added
267 (Work in progress). mn10300-elf.
269 * REMOVED configurations and files
271 VxWorks and the XDR protocol *-*-vxworks
272 Motorola MCORE mcore-*-*
273 National Semiconductor NS32000 ns32k-*-*
275 * New "set print array-indexes" command
277 After turning this setting "on", GDB prints the index of each element
278 when displaying arrays. The default is "off" to preserve the previous
281 * VAX floating point support
283 GDB now supports the not-quite-ieee VAX F and D floating point formats.
285 * User-defined command support
287 In addition to using $arg0..$arg9 for argument passing, it is now possible
288 to use $argc to determine now many arguments have been passed. See the
289 section on user-defined commands in the user manual for more information.
291 *** Changes in GDB 6.3:
293 * New command line option
295 GDB now accepts -l followed by a number to set the timeout for remote
298 * GDB works with GCC -feliminate-dwarf2-dups
300 GDB now supports a more compact representation of DWARF-2 debug
301 information using DW_FORM_ref_addr references. These are produced
302 by GCC with the option -feliminate-dwarf2-dups and also by some
303 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
304 to use -feliminate-dwarf2-dups.
306 * Internationalization
308 When supported by the host system, GDB will be built with
309 internationalization (libintl). The task of marking up the sources is
310 continued, we're looking forward to our first translation.
314 Initial support for debugging programs compiled with the GNAT
315 implementation of the Ada programming language has been integrated
316 into GDB. In this release, support is limited to expression evaluation.
318 * New native configurations
320 GNU/Linux/m32r m32r-*-linux-gnu
324 GDB's remote protocol now includes support for the 'p' packet. This
325 packet is used to fetch individual registers from a remote inferior.
327 * END-OF-LIFE registers[] compatibility module
329 GDB's internal register infrastructure has been completely rewritten.
330 The new infrastructure making possible the implementation of key new
331 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
334 GDB 6.3 will be the last release to include the the registers[]
335 compatibility module that allowed out-of-date configurations to
336 continue to work. This change directly impacts the following
348 Unless there is activity to revive these configurations, they will be
349 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
351 * OBSOLETE configurations and files
353 Configurations that have been declared obsolete in this release have
354 been commented out. Unless there is activity to revive these
355 configurations, the next release of GDB will have their sources
365 *** Changes in GDB 6.2.1:
367 * MIPS `break main; run' gave an heuristic-fence-post warning
369 When attempting to run even a simple program, a warning about
370 heuristic-fence-post being hit would be reported. This problem has
373 * MIPS IRIX 'long double' crashed GDB
375 When examining a long double variable, GDB would get a segmentation
376 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
377 IRIX long double values).
381 A bug in the VAX stack code was causing problems with the "next"
382 command. This problem has been fixed.
384 *** Changes in GDB 6.2:
386 * Fix for ``many threads''
388 On GNU/Linux systems that use the NPTL threads library, a program
389 rapidly creating and deleting threads would confuse GDB leading to the
392 ptrace: No such process.
393 thread_db_get_info: cannot get thread info: generic error
395 This problem has been fixed.
397 * "-async" and "-noasync" options removed.
399 Support for the broken "-noasync" option has been removed (it caused
402 * New ``start'' command.
404 This command runs the program until the begining of the main procedure.
406 * New BSD Kernel Data Access Library (libkvm) interface
408 Using ``target kvm'' it is now possible to debug kernel core dumps and
409 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
410 platforms. Currently supported (native-only) configurations are:
412 FreeBSD/amd64 x86_64-*-freebsd*
413 FreeBSD/i386 i?86-*-freebsd*
414 NetBSD/i386 i?86-*-netbsd*
415 NetBSD/m68k m68*-*-netbsd*
416 NetBSD/sparc sparc-*-netbsd*
417 OpenBSD/amd64 x86_64-*-openbsd*
418 OpenBSD/i386 i?86-*-openbsd*
419 OpenBSD/m68k m68*-openbsd*
420 OpenBSD/sparc sparc-*-openbsd*
422 * Signal trampoline code overhauled
424 Many generic problems with GDB's signal handling code have been fixed.
425 These include: backtraces through non-contiguous stacks; recognition
426 of sa_sigaction signal trampolines; backtrace from a NULL pointer
427 call; backtrace through a signal trampoline; step into and out of
428 signal handlers; and single-stepping in the signal trampoline.
430 Please note that kernel bugs are a limiting factor here. These
431 features have been shown to work on an s390 GNU/Linux system that
432 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
434 * Cygwin support for DWARF 2 added.
436 * New native configurations
438 GNU/Linux/hppa hppa*-*-linux*
439 OpenBSD/hppa hppa*-*-openbsd*
440 OpenBSD/m68k m68*-*-openbsd*
441 OpenBSD/m88k m88*-*-openbsd*
442 OpenBSD/powerpc powerpc-*-openbsd*
443 NetBSD/vax vax-*-netbsd*
444 OpenBSD/vax vax-*-openbsd*
446 * END-OF-LIFE frame compatibility module
448 GDB's internal frame infrastructure has been completely rewritten.
449 The new infrastructure making it possible to support key new features
450 including DWARF 2 Call Frame Information. To aid in the task of
451 migrating old configurations to this new infrastructure, a
452 compatibility module, that allowed old configurations to continue to
453 work, was also included.
455 GDB 6.2 will be the last release to include this frame compatibility
456 module. This change directly impacts the following configurations:
466 Unless there is activity to revive these configurations, they will be
467 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
469 * REMOVED configurations and files
471 Sun 3, running SunOS 3 m68*-*-sunos3*
472 Sun 3, running SunOS 4 m68*-*-sunos4*
473 Sun 2, running SunOS 3 m68000-*-sunos3*
474 Sun 2, running SunOS 4 m68000-*-sunos4*
475 Motorola 680x0 running LynxOS m68*-*-lynxos*
476 AT&T 3b1/Unix pc m68*-att-*
477 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
478 decstation mips-dec-* mips-little-*
479 riscos mips-*-riscos* mips-*-sysv*
481 sysv mips*-*-sysv4* (IRIX 5/6 not included)
483 *** Changes in GDB 6.1.1:
485 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
487 The TUI (Text-mode User Interface) is now built as part of a default
488 GDB configuration. It is enabled by either selecting the TUI with the
489 command line option "-i=tui" or by running the separate "gdbtui"
490 program. For more information on the TUI, see the manual "Debugging
493 * Pending breakpoint support (also included in GDB 6.1)
495 Support has been added to allow you to specify breakpoints in shared
496 libraries that have not yet been loaded. If a breakpoint location
497 cannot be found, and the "breakpoint pending" option is set to auto,
498 GDB queries you if you wish to make the breakpoint pending on a future
499 shared-library load. If and when GDB resolves the breakpoint symbol,
500 the pending breakpoint is removed as one or more regular breakpoints
503 Pending breakpoints are very useful for GCJ Java debugging.
505 * Fixed ISO-C build problems
507 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
508 non ISO-C code that stopped them being built using a more strict ISO-C
509 compiler (e.g., IBM's C compiler).
511 * Fixed build problem on IRIX 5
513 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
514 wasn't able to compile compile on an IRIX 5 system.
516 * Added execute permission to gdb/gdbserver/configure
518 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
519 permission. This bug would cause configure to fail on a number of
520 systems (Solaris, IRIX). Ref: server/519.
522 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
524 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
525 has been updated to use constant array sizes.
527 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
529 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
530 its generated DWARF Call Frame Info. This encoding was causing GDB to
531 panic, that panic has been fixed. Ref: gdb/1628.
533 * Fixed a problem when examining parameters in shared library code.
535 When examining parameters in optimized shared library code generated
536 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
537 not available''. GDB now correctly displays the variable's value.
539 *** Changes in GDB 6.1:
541 * Removed --with-mmalloc
543 Support for the mmalloc memory manager has been removed, as it
544 conflicted with the internal gdb byte cache.
546 * Changes in AMD64 configurations
548 The AMD64 target now includes the %cs and %ss registers. As a result
549 the AMD64 remote protocol has changed; this affects the floating-point
550 and SSE registers. If you rely on those registers for your debugging,
551 you should upgrade gdbserver on the remote side.
553 * Revised SPARC target
555 The SPARC target has been completely revised, incorporating the
556 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
557 support for LynxOS and SunOS 4 has been dropped. Calling functions
558 from within GDB on operating systems with a non-executable stack
559 (Solaris, OpenBSD) now works.
563 GDB has a new C++ demangler which does a better job on the mangled
564 names generated by current versions of g++. It also runs faster, so
565 with this and other changes gdb should now start faster on large C++
568 * DWARF 2 Location Expressions
570 GDB support for location expressions has been extended to support function
571 arguments and frame bases. Older versions of GDB could crash when they
574 * C++ nested types and namespaces
576 GDB's support for nested types and namespaces in C++ has been
577 improved, especially if you use the DWARF 2 debugging format. (This
578 is the default for recent versions of GCC on most platforms.)
579 Specifically, if you have a class "Inner" defined within a class or
580 namespace "Outer", then GDB realizes that the class's name is
581 "Outer::Inner", not simply "Inner". This should greatly reduce the
582 frequency of complaints about not finding RTTI symbols. In addition,
583 if you are stopped at inside of a function defined within a namespace,
584 GDB modifies its name lookup accordingly.
586 * New native configurations
588 NetBSD/amd64 x86_64-*-netbsd*
589 OpenBSD/amd64 x86_64-*-openbsd*
590 OpenBSD/alpha alpha*-*-openbsd*
591 OpenBSD/sparc sparc-*-openbsd*
592 OpenBSD/sparc64 sparc64-*-openbsd*
594 * New debugging protocols
596 M32R with SDI protocol m32r-*-elf*
598 * "set prompt-escape-char" command deleted.
600 The command "set prompt-escape-char" has been deleted. This command,
601 and its very obscure effet on GDB's prompt, was never documented,
602 tested, nor mentioned in the NEWS file.
604 * OBSOLETE configurations and files
606 Configurations that have been declared obsolete in this release have
607 been commented out. Unless there is activity to revive these
608 configurations, the next release of GDB will have their sources
611 Sun 3, running SunOS 3 m68*-*-sunos3*
612 Sun 3, running SunOS 4 m68*-*-sunos4*
613 Sun 2, running SunOS 3 m68000-*-sunos3*
614 Sun 2, running SunOS 4 m68000-*-sunos4*
615 Motorola 680x0 running LynxOS m68*-*-lynxos*
616 AT&T 3b1/Unix pc m68*-att-*
617 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
618 decstation mips-dec-* mips-little-*
619 riscos mips-*-riscos* mips-*-sysv*
621 sysv mips*-*-sysv4* (IRIX 5/6 not included)
623 * REMOVED configurations and files
625 SGI Irix-4.x mips-sgi-irix4 or iris4
626 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
627 Z8000 simulator z8k-zilog-none or z8ksim
628 Matsushita MN10200 w/simulator mn10200-*-*
629 H8/500 simulator h8500-hitachi-hms or h8500hms
630 HP/PA running BSD hppa*-*-bsd*
631 HP/PA running OSF/1 hppa*-*-osf*
632 HP/PA Pro target hppa*-*-pro*
633 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
634 386BSD i[3456]86-*-bsd*
635 Sequent family i[3456]86-sequent-sysv4*
636 i[3456]86-sequent-sysv*
637 i[3456]86-sequent-bsd*
638 SPARC running LynxOS sparc-*-lynxos*
639 SPARC running SunOS 4 sparc-*-sunos4*
640 Tsqware Sparclet sparclet-*-*
641 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
643 *** Changes in GDB 6.0:
647 Support for debugging the Objective-C programming language has been
650 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
652 DWARF 2's Call Frame Information makes available compiler generated
653 information that more exactly describes the program's run-time stack.
654 By using this information, GDB is able to provide more robust stack
657 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
658 have been updated to use a new backtrace mechanism which includes
663 GDB's remote protocol has been extended to include support for hosted
664 file I/O (where the remote target uses GDB's file system). See GDB's
665 remote protocol documentation for details.
667 * All targets using the new architecture framework.
669 All of GDB's targets have been updated to use the new internal
670 architecture framework. The way is now open for future GDB releases
671 to include cross-architecture native debugging support (i386 on amd64,
674 * GNU/Linux's Thread Local Storage (TLS)
676 GDB now includes support for for the GNU/Linux implementation of
677 per-thread variables.
679 * GNU/Linux's Native POSIX Thread Library (NPTL)
681 GDB's thread code has been updated to work with either the new
682 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
684 * Separate debug info.
686 GDB, in conjunction with BINUTILS, now supports a mechanism for
687 automatically loading debug information from a separate file. Instead
688 of shipping full debug and non-debug versions of system libraries,
689 system integrators can now instead ship just the stripped libraries
690 and optional debug files.
692 * DWARF 2 Location Expressions
694 DWARF 2 Location Expressions allow the compiler to more completely
695 describe the location of variables (even in optimized code) to the
698 GDB now includes preliminary support for location expressions (support
699 for DW_OP_piece is still missing).
703 A number of long standing bugs that caused GDB to die while starting a
704 Java application have been fixed. GDB's Java support is now
705 considered "useable".
707 * GNU/Linux support for fork, vfork, and exec.
709 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
710 commands are now implemented for GNU/Linux. They require a 2.5.x or later
713 * GDB supports logging output to a file
715 There are two new commands, "set logging" and "show logging", which can be
716 used to capture GDB's output to a file.
718 * The meaning of "detach" has changed for gdbserver
720 The "detach" command will now resume the application, as documented. To
721 disconnect from gdbserver and leave it stopped, use the new "disconnect"
724 * d10v, m68hc11 `regs' command deprecated
726 The `info registers' command has been updated so that it displays the
727 registers using a format identical to the old `regs' command.
731 A new command, "maint set profile on/off", has been added. This command can
732 be used to enable or disable profiling while running GDB, to profile a
733 session or a set of commands. In addition there is a new configure switch,
734 "--enable-profiling", which will cause GDB to be compiled with profiling
735 data, for more informative profiling results.
737 * Default MI syntax changed to "mi2".
739 The default MI (machine interface) syntax, enabled by the command line
740 option "-i=mi", has been changed to "mi2". The previous MI syntax,
741 "mi1", can be enabled by specifying the option "-i=mi1".
743 Support for the original "mi0" syntax (included in GDB 5.0) has been
746 Fix for gdb/192: removed extraneous space when displaying frame level.
747 Fix for gdb/672: update changelist is now output in mi list format.
748 Fix for gdb/702: a -var-assign that updates the value now shows up
749 in a subsequent -var-update.
751 * New native configurations.
753 FreeBSD/amd64 x86_64-*-freebsd*
755 * Multi-arched targets.
757 HP/PA HPUX11 hppa*-*-hpux*
758 Renesas M32R/D w/simulator m32r-*-elf*
760 * OBSOLETE configurations and files
762 Configurations that have been declared obsolete in this release have
763 been commented out. Unless there is activity to revive these
764 configurations, the next release of GDB will have their sources
767 Z8000 simulator z8k-zilog-none or z8ksim
768 Matsushita MN10200 w/simulator mn10200-*-*
769 H8/500 simulator h8500-hitachi-hms or h8500hms
770 HP/PA running BSD hppa*-*-bsd*
771 HP/PA running OSF/1 hppa*-*-osf*
772 HP/PA Pro target hppa*-*-pro*
773 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
774 Sequent family i[3456]86-sequent-sysv4*
775 i[3456]86-sequent-sysv*
776 i[3456]86-sequent-bsd*
777 Tsqware Sparclet sparclet-*-*
778 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
780 * REMOVED configurations and files
783 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
784 IBM AIX PS/2 i[3456]86-*-aix
785 i386 running Mach 3.0 i[3456]86-*-mach3*
786 i386 running Mach i[3456]86-*-mach*
787 i386 running OSF/1 i[3456]86-*osf1mk*
788 HP/Apollo 68k Family m68*-apollo*-sysv*,
790 m68*-hp-bsd*, m68*-hp-hpux*
791 Argonaut Risc Chip (ARC) arc-*-*
792 Mitsubishi D30V d30v-*-*
793 Fujitsu FR30 fr30-*-elf*
794 OS/9000 i[34]86-*-os9k
795 I960 with MON960 i960-*-coff
797 * MIPS $fp behavior changed
799 The convenience variable $fp, for the MIPS, now consistently returns
800 the address of the current frame's base. Previously, depending on the
801 context, $fp could refer to either $sp or the current frame's base
802 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
803 The GNU Source-Level Debugger''.
805 *** Changes in GDB 5.3:
807 * GNU/Linux shared library multi-threaded performance improved.
809 When debugging a multi-threaded application on GNU/Linux, GDB now uses
810 `/proc', in preference to `ptrace' for memory reads. This may result
811 in an improvement in the start-up time of multi-threaded, shared
812 library applications when run under GDB. One GDB user writes: ``loads
813 shared libs like mad''.
815 * ``gdbserver'' now supports multi-threaded applications on some targets
817 Support for debugging multi-threaded applications which use
818 the GNU/Linux LinuxThreads package has been added for
819 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
820 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
822 * GDB now supports C/C++ preprocessor macros.
824 GDB now expands preprocessor macro invocations in C/C++ expressions,
825 and provides various commands for showing macro definitions and how
828 The new command `macro expand EXPRESSION' expands any macro
829 invocations in expression, and shows the result.
831 The new command `show macro MACRO-NAME' shows the definition of the
832 macro named MACRO-NAME, and where it was defined.
834 Most compilers don't include information about macros in the debugging
835 information by default. In GCC 3.1, for example, you need to compile
836 your program with the options `-gdwarf-2 -g3'. If the macro
837 information is present in the executable, GDB will read it.
839 * Multi-arched targets.
841 DEC Alpha (partial) alpha*-*-*
842 DEC VAX (partial) vax-*-*
844 National Semiconductor NS32000 (partial) ns32k-*-*
845 Motorola 68000 (partial) m68k-*-*
846 Motorola MCORE mcore-*-*
850 Fujitsu FRV architecture added by Red Hat frv*-*-*
853 * New native configurations
855 Alpha NetBSD alpha*-*-netbsd*
856 SH NetBSD sh*-*-netbsdelf*
857 MIPS NetBSD mips*-*-netbsd*
858 UltraSPARC NetBSD sparc64-*-netbsd*
860 * OBSOLETE configurations and files
862 Configurations that have been declared obsolete in this release have
863 been commented out. Unless there is activity to revive these
864 configurations, the next release of GDB will have their sources
867 Mitsubishi D30V d30v-*-*
868 OS/9000 i[34]86-*-os9k
869 IBM AIX PS/2 i[3456]86-*-aix
870 Fujitsu FR30 fr30-*-elf*
871 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
872 Argonaut Risc Chip (ARC) arc-*-*
873 i386 running Mach 3.0 i[3456]86-*-mach3*
874 i386 running Mach i[3456]86-*-mach*
875 i386 running OSF/1 i[3456]86-*osf1mk*
876 HP/Apollo 68k Family m68*-apollo*-sysv*,
878 m68*-hp-bsd*, m68*-hp-hpux*
879 I960 with MON960 i960-*-coff
883 CHILL, a Pascal like language used by telecommunications companies.
885 * REMOVED configurations and files
887 AMD 29k family via UDI a29k-amd-udi, udi29k
888 A29K VxWorks a29k-*-vxworks
889 AMD 29000 embedded, using EBMON a29k-none-none
890 AMD 29000 embedded with COFF a29k-none-coff
891 AMD 29000 embedded with a.out a29k-none-aout
893 testsuite/gdb.hp/gdb.threads-hp/ directory
895 * New command "set max-user-call-depth <nnn>"
897 This command allows the user to limit the call depth of user-defined
898 commands. The default is 1024.
900 * Changes in FreeBSD/i386 native debugging.
902 Support for the "generate-core-file" has been added.
904 * New commands "dump", "append", and "restore".
906 These commands allow data to be copied from target memory
907 to a bfd-format or binary file (dump and append), and back
908 from a file into memory (restore).
910 * Improved "next/step" support on multi-processor Alpha Tru64.
912 The previous single-step mechanism could cause unpredictable problems,
913 including the random appearance of SIGSEGV or SIGTRAP signals. The use
914 of a software single-step mechanism prevents this.
916 *** Changes in GDB 5.2.1:
924 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
925 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
926 Fix, by Joel Brobecker imported from mainline.
928 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
929 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
930 Fix, by Fred Fish, imported from mainline.
932 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
933 Surprisingly enough, it works now.
934 By Michal Ludvig, imported from mainline.
936 i386 hardware watchpoint support:
937 avoid misses on second run for some targets.
938 By Pierre Muller, imported from mainline.
940 *** Changes in GDB 5.2:
942 * New command "set trust-readonly-sections on[off]".
944 This command is a hint that tells gdb that read-only sections
945 really are read-only (ie. that their contents will not change).
946 In this mode, gdb will go to the object file rather than the
947 target to read memory from read-only sections (such as ".text").
948 This can be a significant performance improvement on some
949 (notably embedded) targets.
951 * New command "generate-core-file" (or "gcore").
953 This new gdb command allows the user to drop a core file of the child
954 process state at any time. So far it's been implemented only for
955 GNU/Linux and Solaris, but should be relatively easily ported to other
956 hosts. Argument is core file name (defaults to core.<pid>).
958 * New command line option
960 GDB now accepts --pid or -p followed by a process id.
962 * Change in command line behavior -- corefiles vs. process ids.
964 There is a subtle behavior in the way in which GDB handles
965 command line arguments. The first non-flag argument is always
966 a program to debug, but the second non-flag argument may either
967 be a corefile or a process id. Previously, GDB would attempt to
968 open the second argument as a corefile, and if that failed, would
969 issue a superfluous error message and then attempt to attach it as
970 a process. Now, if the second argument begins with a non-digit,
971 it will be treated as a corefile. If it begins with a digit,
972 GDB will attempt to attach it as a process, and if no such process
973 is found, will then attempt to open it as a corefile.
975 * Changes in ARM configurations.
977 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
978 configuration is fully multi-arch.
980 * New native configurations
982 ARM NetBSD arm*-*-netbsd*
983 x86 OpenBSD i[3456]86-*-openbsd*
984 AMD x86-64 running GNU/Linux x86_64-*-linux-*
985 Sparc64 running FreeBSD sparc64-*-freebsd*
989 Sanyo XStormy16 xstormy16-elf
991 * OBSOLETE configurations and files
993 Configurations that have been declared obsolete in this release have
994 been commented out. Unless there is activity to revive these
995 configurations, the next release of GDB will have their sources
998 AMD 29k family via UDI a29k-amd-udi, udi29k
999 A29K VxWorks a29k-*-vxworks
1000 AMD 29000 embedded, using EBMON a29k-none-none
1001 AMD 29000 embedded with COFF a29k-none-coff
1002 AMD 29000 embedded with a.out a29k-none-aout
1004 testsuite/gdb.hp/gdb.threads-hp/ directory
1006 * REMOVED configurations and files
1008 TI TMS320C80 tic80-*-*
1010 PowerPC Solaris powerpcle-*-solaris*
1011 PowerPC Windows NT powerpcle-*-cygwin32
1012 PowerPC Netware powerpc-*-netware*
1013 Harris/CXUX m88k m88*-harris-cxux*
1014 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1015 ns32k-utek-sysv* ns32k-utek-*
1016 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1017 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1018 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1019 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1020 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1022 * Changes to command line processing
1024 The new `--args' feature can be used to specify command-line arguments
1025 for the inferior from gdb's command line.
1027 * Changes to key bindings
1029 There is a new `operate-and-get-next' function bound to `C-o'.
1031 *** Changes in GDB 5.1.1
1033 Fix compile problem on DJGPP.
1035 Fix a problem with floating-point registers on the i386 being
1038 Fix to stop GDB crashing on .debug_str debug info.
1040 Numerous documentation fixes.
1042 Numerous testsuite fixes.
1044 *** Changes in GDB 5.1:
1046 * New native configurations
1048 Alpha FreeBSD alpha*-*-freebsd*
1049 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1050 MIPS GNU/Linux mips*-*-linux*
1051 MIPS SGI Irix 6.x mips*-sgi-irix6*
1052 ia64 AIX ia64-*-aix*
1053 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1057 Motorola 68HC11 and 68HC12 m68hc11-elf
1059 UltraSparc running GNU/Linux sparc64-*-linux*
1061 * OBSOLETE configurations and files
1063 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1064 Harris/CXUX m88k m88*-harris-cxux*
1065 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1066 ns32k-utek-sysv* ns32k-utek-*
1067 TI TMS320C80 tic80-*-*
1069 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1070 PowerPC Solaris powerpcle-*-solaris*
1071 PowerPC Windows NT powerpcle-*-cygwin32
1072 PowerPC Netware powerpc-*-netware*
1073 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1074 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1075 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1076 Apple Macintosh (MPW) host N/A
1078 stuff.c (Program to stuff files into a specially prepared space in kdb)
1079 kdb-start.c (Main loop for the standalone kernel debugger)
1081 Configurations that have been declared obsolete in this release have
1082 been commented out. Unless there is activity to revive these
1083 configurations, the next release of GDB will have their sources
1084 permanently REMOVED.
1086 * REMOVED configurations and files
1088 Altos 3068 m68*-altos-*
1089 Convex c1-*-*, c2-*-*
1091 ARM RISCix arm-*-* (as host)
1095 * GDB has been converted to ISO C.
1097 GDB's source code has been converted to ISO C. In particular, the
1098 sources are fully protoized, and rely on standard headers being
1103 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1105 * The MI enabled by default.
1107 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1108 revised and enabled by default. Packages which use GDB as a debugging
1109 engine behind a UI or another front end are encouraged to switch to
1110 using the GDB/MI interface, instead of the old annotations interface
1111 which is now deprecated.
1113 * Support for debugging Pascal programs.
1115 GDB now includes support for debugging Pascal programs. The following
1116 main features are supported:
1118 - Pascal-specific data types such as sets;
1120 - automatic recognition of Pascal sources based on file-name
1123 - Pascal-style display of data types, variables, and functions;
1125 - a Pascal expression parser.
1127 However, some important features are not yet supported.
1129 - Pascal string operations are not supported at all;
1131 - there are some problems with boolean types;
1133 - Pascal type hexadecimal constants are not supported
1134 because they conflict with the internal variables format;
1136 - support for Pascal objects and classes is not full yet;
1138 - unlike Pascal, GDB is case-sensitive for symbol names.
1140 * Changes in completion.
1142 Commands such as `shell', `run' and `set args', which pass arguments
1143 to inferior programs, now complete on file names, similar to what
1144 users expect at the shell prompt.
1146 Commands which accept locations, such as `disassemble', `print',
1147 `breakpoint', `until', etc. now complete on filenames as well as
1148 program symbols. Thus, if you type "break foob TAB", and the source
1149 files linked into the programs include `foobar.c', that file name will
1150 be one of the candidates for completion. However, file names are not
1151 considered for completion after you typed a colon that delimits a file
1152 name from a name of a function in that file, as in "break foo.c:bar".
1154 `set demangle-style' completes on available demangling styles.
1156 * New platform-independent commands:
1158 It is now possible to define a post-hook for a command as well as a
1159 hook that runs before the command. For more details, see the
1160 documentation of `hookpost' in the GDB manual.
1162 * Changes in GNU/Linux native debugging.
1164 Support for debugging multi-threaded programs has been completely
1165 revised for all platforms except m68k and sparc. You can now debug as
1166 many threads as your system allows you to have.
1168 Attach/detach is supported for multi-threaded programs.
1170 Support for SSE registers was added for x86. This doesn't work for
1171 multi-threaded programs though.
1173 * Changes in MIPS configurations.
1175 Multi-arch support is enabled for all MIPS configurations.
1177 GDB can now be built as native debugger on SGI Irix 6.x systems for
1178 debugging n32 executables. (Debugging 64-bit executables is not yet
1181 * Unified support for hardware watchpoints in all x86 configurations.
1183 Most (if not all) native x86 configurations support hardware-assisted
1184 breakpoints and watchpoints in a unified manner. This support
1185 implements debug register sharing between watchpoints, which allows to
1186 put a virtually infinite number of watchpoints on the same address,
1187 and also supports watching regions up to 16 bytes with several debug
1190 The new maintenance command `maintenance show-debug-regs' toggles
1191 debugging print-outs in functions that insert, remove, and test
1192 watchpoints and hardware breakpoints.
1194 * Changes in the DJGPP native configuration.
1196 New command ``info dos sysinfo'' displays assorted information about
1197 the CPU, OS, memory, and DPMI server.
1199 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1200 display information about segment descriptors stored in GDT, LDT, and
1203 New commands ``info dos pde'' and ``info dos pte'' display entries
1204 from Page Directory and Page Tables (for now works with CWSDPMI only).
1205 New command ``info dos address-pte'' displays the Page Table entry for
1206 a given linear address.
1208 GDB can now pass command lines longer than 126 characters to the
1209 program being debugged (requires an update to the libdbg.a library
1210 which is part of the DJGPP development kit).
1212 DWARF2 debug info is now supported.
1214 It is now possible to `step' and `next' through calls to `longjmp'.
1216 * Changes in documentation.
1218 All GDB documentation was converted to GFDL, the GNU Free
1219 Documentation License.
1221 Tracepoints-related commands are now fully documented in the GDB
1224 TUI, the Text-mode User Interface, is now documented in the manual.
1226 Tracepoints-related commands are now fully documented in the GDB
1229 The "GDB Internals" manual now has an index. It also includes
1230 documentation of `ui_out' functions, GDB coding standards, x86
1231 hardware watchpoints, and memory region attributes.
1233 * GDB's version number moved to ``version.in''
1235 The Makefile variable VERSION has been replaced by the file
1236 ``version.in''. People creating GDB distributions should update the
1237 contents of this file.
1241 GUD support is now a standard part of the EMACS distribution.
1243 *** Changes in GDB 5.0:
1245 * Improved support for debugging FP programs on x86 targets
1247 Unified and much-improved support for debugging floating-point
1248 programs on all x86 targets. In particular, ``info float'' now
1249 displays the FP registers in the same format on all x86 targets, with
1250 greater level of detail.
1252 * Improvements and bugfixes in hardware-assisted watchpoints
1254 It is now possible to watch array elements, struct members, and
1255 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1256 on x86 targets no longer erroneously trigger when the address is
1259 * Improvements in the native DJGPP version of GDB
1261 The distribution now includes all the scripts and auxiliary files
1262 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1263 machines ``out of the box''.
1265 The DJGPP version can now debug programs that use signals. It is
1266 possible to catch signals that happened in the debuggee, deliver
1267 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1268 would kill the program being debugged.) Programs that hook hardware
1269 interrupts (keyboard, timer, etc.) can also be debugged.
1271 It is now possible to debug DJGPP programs that redirect their
1272 standard handles or switch them to raw (as opposed to cooked) mode, or
1273 even close them. The command ``run < foo > bar'' works as expected,
1274 and ``info terminal'' reports useful information about the debuggee's
1275 terminal, including raw/cooked mode, redirection, etc.
1277 The DJGPP version now uses termios functions for console I/O, which
1278 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1281 DOS-style file names with drive letters are now fully supported by
1284 It is now possible to debug DJGPP programs that switch their working
1285 directory. It is also possible to rerun the debuggee any number of
1286 times without restarting GDB; thus, you can use the same setup,
1287 breakpoints, etc. for many debugging sessions.
1289 * New native configurations
1291 ARM GNU/Linux arm*-*-linux*
1292 PowerPC GNU/Linux powerpc-*-linux*
1296 Motorola MCore mcore-*-*
1297 x86 VxWorks i[3456]86-*-vxworks*
1298 PowerPC VxWorks powerpc-*-vxworks*
1299 TI TMS320C80 tic80-*-*
1301 * OBSOLETE configurations
1303 Altos 3068 m68*-altos-*
1304 Convex c1-*-*, c2-*-*
1306 ARM RISCix arm-*-* (as host)
1309 Configurations that have been declared obsolete will be commented out,
1310 but the code will be left in place. If there is no activity to revive
1311 these configurations before the next release of GDB, the sources will
1312 be permanently REMOVED.
1314 * Gould support removed
1316 Support for the Gould PowerNode and NP1 has been removed.
1318 * New features for SVR4
1320 On SVR4 native platforms (such as Solaris), if you attach to a process
1321 without first loading a symbol file, GDB will now attempt to locate and
1322 load symbols from the running process's executable file.
1324 * Many C++ enhancements
1326 C++ support has been greatly improved. Overload resolution now works properly
1327 in almost all cases. RTTI support is on the way.
1329 * Remote targets can connect to a sub-program
1331 A popen(3) style serial-device has been added. This device starts a
1332 sub-process (such as a stand-alone simulator) and then communicates
1333 with that. The sub-program to run is specified using the syntax
1334 ``|<program> <args>'' vis:
1336 (gdb) set remotedebug 1
1337 (gdb) target extended-remote |mn10300-elf-sim program-args
1339 * MIPS 64 remote protocol
1341 A long standing bug in the mips64 remote protocol where by GDB
1342 expected certain 32 bit registers (ex SR) to be transfered as 32
1343 instead of 64 bits has been fixed.
1345 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1346 added to provide backward compatibility with older versions of GDB.
1348 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1350 The command ``set remotebinarydownload'' command has been replaced by
1351 ``set remote X-packet''. Other commands in ``set remote'' family
1352 include ``set remote P-packet''.
1354 * Breakpoint commands accept ranges.
1356 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1357 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1358 ``tracepoint passcount'' also accepts a range of tracepoints.
1360 * ``apropos'' command added.
1362 The ``apropos'' command searches through command names and
1363 documentation strings, printing out matches, making it much easier to
1364 try to find a command that does what you are looking for.
1368 A new machine oriented interface (MI) has been added to GDB. This
1369 interface is designed for debug environments running GDB as a separate
1370 process. This is part of the long term libGDB project. See the
1371 "GDB/MI" chapter of the GDB manual for further information. It can be
1372 enabled by configuring with:
1374 .../configure --enable-gdbmi
1376 *** Changes in GDB-4.18:
1378 * New native configurations
1380 HP-UX 10.20 hppa*-*-hpux10.20
1381 HP-UX 11.x hppa*-*-hpux11.0*
1382 M68K GNU/Linux m68*-*-linux*
1386 Fujitsu FR30 fr30-*-elf*
1387 Intel StrongARM strongarm-*-*
1388 Mitsubishi D30V d30v-*-*
1390 * OBSOLETE configurations
1392 Gould PowerNode, NP1 np1-*-*, pn-*-*
1394 Configurations that have been declared obsolete will be commented out,
1395 but the code will be left in place. If there is no activity to revive
1396 these configurations before the next release of GDB, the sources will
1397 be permanently REMOVED.
1401 As a compatibility experiment, GDB's source files buildsym.h and
1402 buildsym.c have been converted to pure standard C, no longer
1403 containing any K&R compatibility code. We believe that all systems in
1404 use today either come with a standard C compiler, or have a GCC port
1405 available. If this is not true, please report the affected
1406 configuration to bug-gdb@gnu.org immediately. See the README file for
1407 information about getting a standard C compiler if you don't have one
1412 GDB now uses readline 2.2.
1414 * set extension-language
1416 You can now control the mapping between filename extensions and source
1417 languages by using the `set extension-language' command. For instance,
1418 you can ask GDB to treat .c files as C++ by saying
1419 set extension-language .c c++
1420 The command `info extensions' lists all of the recognized extensions
1421 and their associated languages.
1423 * Setting processor type for PowerPC and RS/6000
1425 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1426 you can use the `set processor' command to specify what variant of the
1427 PowerPC family you are debugging. The command
1431 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
1432 following PowerPC and RS6000 variants:
1434 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
1435 rs6000 IBM RS6000 ("POWER") architecture, user-level view
1437 403GC IBM PowerPC 403GC
1438 505 Motorola PowerPC 505
1439 860 Motorola PowerPC 860 or 850
1440 601 Motorola PowerPC 601
1441 602 Motorola PowerPC 602
1442 603 Motorola/IBM PowerPC 603 or 603e
1443 604 Motorola PowerPC 604 or 604e
1444 750 Motorola/IBM PowerPC 750 or 750
1446 At the moment, this command just tells GDB what to name the
1447 special-purpose processor registers. Since almost all the affected
1448 registers are inaccessible to user-level programs, this command is
1449 only useful for remote debugging in its present form.
1453 Thanks to a major code donation from Hewlett-Packard, GDB now has much
1454 more extensive support for HP-UX. Added features include shared
1455 library support, kernel threads and hardware watchpoints for 11.00,
1456 support for HP's ANSI C and C++ compilers, and a compatibility mode
1457 for xdb and dbx commands.
1461 HP's donation includes the new concept of catchpoints, which is a
1462 generalization of the old catch command. On HP-UX, it is now possible
1463 to catch exec, fork, and vfork, as well as library loading.
1465 This means that the existing catch command has changed; its first
1466 argument now specifies the type of catch to be set up. See the
1467 output of "help catch" for a list of catchpoint types.
1469 * Debugging across forks
1471 On HP-UX, you can choose which process to debug when a fork() happens
1476 HP has donated a curses-based terminal user interface (TUI). To get
1477 it, build with --enable-tui. Although this can be enabled for any
1478 configuration, at present it only works for native HP debugging.
1480 * GDB remote protocol additions
1482 A new protocol packet 'X' that writes binary data is now available.
1483 Default behavior is to try 'X', then drop back to 'M' if the stub
1484 fails to respond. The settable variable `remotebinarydownload'
1485 allows explicit control over the use of 'X'.
1487 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1488 full 64-bit address. The command
1490 set remoteaddresssize 32
1492 can be used to revert to the old behaviour. For existing remote stubs
1493 the change should not be noticed, as the additional address information
1496 In order to assist in debugging stubs, you may use the maintenance
1497 command `packet' to send any text string to the stub. For instance,
1499 maint packet heythere
1501 sends the packet "$heythere#<checksum>". Note that it is very easy to
1502 disrupt a debugging session by sending the wrong packet at the wrong
1505 The compare-sections command allows you to compare section data on the
1506 target to what is in the executable file without uploading or
1507 downloading, by comparing CRC checksums.
1509 * Tracing can collect general expressions
1511 You may now collect general expressions at tracepoints. This requires
1512 further additions to the target-side stub; see tracepoint.c and
1513 doc/agentexpr.texi for further details.
1515 * mask-address variable for Mips
1517 For Mips targets, you may control the zeroing of the upper 32 bits of
1518 a 64-bit address by entering `set mask-address on'. This is mainly
1519 of interest to users of embedded R4xxx and R5xxx processors.
1521 * Higher serial baud rates
1523 GDB's serial code now allows you to specify baud rates 57600, 115200,
1524 230400, and 460800 baud. (Note that your host system may not be able
1525 to achieve all of these rates.)
1529 The i960 configuration now includes an initial implementation of a
1530 builtin simulator, contributed by Jim Wilson.
1533 *** Changes in GDB-4.17:
1535 * New native configurations
1537 Alpha GNU/Linux alpha*-*-linux*
1538 Unixware 2.x i[3456]86-unixware2*
1539 Irix 6.x mips*-sgi-irix6*
1540 PowerPC GNU/Linux powerpc-*-linux*
1541 PowerPC Solaris powerpcle-*-solaris*
1542 Sparc GNU/Linux sparc-*-linux*
1543 Motorola sysV68 R3V7.1 m68k-motorola-sysv
1547 Argonaut Risc Chip (ARC) arc-*-*
1548 Hitachi H8/300S h8300*-*-*
1549 Matsushita MN10200 w/simulator mn10200-*-*
1550 Matsushita MN10300 w/simulator mn10300-*-*
1551 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1552 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1553 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1554 Mitsubishi D10V w/simulator d10v-*-*
1555 Mitsubishi M32R/D w/simulator m32r-*-elf*
1556 Tsqware Sparclet sparclet-*-*
1557 NEC V850 w/simulator v850-*-*
1559 * New debugging protocols
1561 ARM with RDI protocol arm*-*-*
1562 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1563 DDB and LSI variants of PMON protocol mips*-*-*
1564 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1565 PowerPC with SDS protocol powerpc{,le}-*-eabi
1566 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1570 All configurations can now understand and use the DWARF 2 debugging
1571 format. The choice is automatic, if the symbol file contains DWARF 2
1576 GDB now includes basic Java language support. This support is
1577 only useful with Java compilers that produce native machine code.
1579 * solib-absolute-prefix and solib-search-path
1581 For SunOS and SVR4 shared libraries, you may now set the prefix for
1582 loading absolute shared library symbol files, and the search path for
1583 locating non-absolute shared library symbol files.
1585 * Live range splitting
1587 GDB can now effectively debug code for which GCC has performed live
1588 range splitting as part of its optimization. See gdb/doc/LRS for
1589 more details on the expected format of the stabs information.
1593 GDB's support for the GNU Hurd, including thread debugging, has been
1594 updated to work with current versions of the Hurd.
1598 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1599 instruction set. ARM GDB automatically detects when Thumb
1600 instructions are in use, and adjusts disassembly and backtracing
1605 GDB's MIPS target configurations now handle the MIP16 16-bit
1610 GDB now includes support for overlays; if an executable has been
1611 linked such that multiple sections are based at the same address, GDB
1612 will decide which section to use for symbolic info. You can choose to
1613 control the decision manually, using overlay commands, or implement
1614 additional target-side support and use "overlay load-target" to bring
1615 in the overlay mapping. Do "help overlay" for more detail.
1619 The command "info symbol <address>" displays information about
1620 the symbol at the specified address.
1624 The standard remote protocol now includes an extension that allows
1625 asynchronous collection and display of trace data. This requires
1626 extensive support in the target-side debugging stub. Tracing mode
1627 includes a new interaction mode in GDB and new commands: see the
1628 file tracepoint.c for more details.
1632 Configurations for embedded MIPS now include a simulator contributed
1633 by Cygnus Solutions. The simulator supports the instruction sets
1634 of most MIPS variants.
1638 Sparc configurations may now include the ERC32 simulator contributed
1639 by the European Space Agency. The simulator is not built into
1640 Sparc targets by default; configure with --enable-sim to include it.
1644 For target configurations that may include multiple variants of a
1645 basic architecture (such as MIPS and SH), you may now set the
1646 architecture explicitly. "set arch" sets, "info arch" lists
1647 the possible architectures.
1649 *** Changes in GDB-4.16:
1651 * New native configurations
1653 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1654 M68K NetBSD m68k-*-netbsd*
1655 PowerPC AIX 4.x powerpc-*-aix*
1656 PowerPC MacOS powerpc-*-macos*
1657 PowerPC Windows NT powerpcle-*-cygwin32
1658 RS/6000 AIX 4.x rs6000-*-aix4*
1662 ARM with RDP protocol arm-*-*
1663 I960 with MON960 i960-*-coff
1664 MIPS VxWorks mips*-*-vxworks*
1665 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1666 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1668 Matra Sparclet sparclet-*-*
1672 The powerpc-eabi configuration now includes the PSIM simulator,
1673 contributed by Andrew Cagney, with assistance from Mike Meissner.
1674 PSIM is a very elaborate model of the PowerPC, including not only
1675 basic instruction set execution, but also details of execution unit
1676 performance and I/O hardware. See sim/ppc/README for more details.
1680 GDB now works with Solaris 2.5.
1682 * Windows 95/NT native
1684 GDB will now work as a native debugger on Windows 95 and Windows NT.
1685 To build it from source, you must use the "gnu-win32" environment,
1686 which uses a DLL to emulate enough of Unix to run the GNU tools.
1687 Further information, binaries, and sources are available at
1688 ftp.cygnus.com, under pub/gnu-win32.
1690 * dont-repeat command
1692 If a user-defined command includes the command `dont-repeat', then the
1693 command will not be repeated if the user just types return. This is
1694 useful if the command is time-consuming to run, so that accidental
1695 extra keystrokes don't run the same command many times.
1697 * Send break instead of ^C
1699 The standard remote protocol now includes an option to send a break
1700 rather than a ^C to the target in order to interrupt it. By default,
1701 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1703 * Remote protocol timeout
1705 The standard remote protocol includes a new variable `remotetimeout'
1706 that allows you to set the number of seconds before GDB gives up trying
1707 to read from the target. The default value is 2.
1709 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1711 By default GDB will automatically keep track of objects as they are
1712 loaded and unloaded by the dynamic linker. By using the command `set
1713 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1714 when shared library events occur, thus allowing you to set breakpoints
1715 in shared libraries which are explicitly loaded by the inferior.
1717 Note this feature does not work on hpux8. On hpux9 you must link
1718 /usr/lib/end.o into your program. This feature should work
1719 automatically on hpux10.
1721 * Irix 5.x hardware watchpoint support
1723 Irix 5 configurations now support the use of hardware watchpoints.
1725 * Mips protocol "SYN garbage limit"
1727 When debugging a Mips target using the `target mips' protocol, you
1728 may set the number of characters that GDB will ignore by setting
1729 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1730 every character. The default value is 1050.
1732 * Recording and replaying remote debug sessions
1734 If you set `remotelogfile' to the name of a file, gdb will write to it
1735 a recording of a remote debug session. This recording may then be
1736 replayed back to gdb using "gdbreplay". See gdbserver/README for
1737 details. This is useful when you have a problem with GDB while doing
1738 remote debugging; you can make a recording of the session and send it
1739 to someone else, who can then recreate the problem.
1741 * Speedups for remote debugging
1743 GDB includes speedups for downloading and stepping MIPS systems using
1744 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1745 and more efficient S-record downloading.
1747 * Memory use reductions and statistics collection
1749 GDB now uses less memory and reports statistics about memory usage.
1750 Try the `maint print statistics' command, for example.
1752 *** Changes in GDB-4.15:
1754 * Psymtabs for XCOFF
1756 The symbol reader for AIX GDB now uses partial symbol tables. This
1757 can greatly improve startup time, especially for large executables.
1759 * Remote targets use caching
1761 Remote targets now use a data cache to speed up communication with the
1762 remote side. The data cache could lead to incorrect results because
1763 it doesn't know about volatile variables, thus making it impossible to
1764 debug targets which use memory mapped I/O devices. `set remotecache
1765 off' turns the the data cache off.
1767 * Remote targets may have threads
1769 The standard remote protocol now includes support for multiple threads
1770 in the target system, using new protocol commands 'H' and 'T'. See
1771 gdb/remote.c for details.
1775 If GDB is configured with `--enable-netrom', then it will include
1776 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1777 acts as though it is a bank of ROM on the target board, but you can
1778 write into it over the network. GDB's support consists only of
1779 support for fast loading into the emulated ROM; to debug, you must use
1780 another protocol, such as standard remote protocol. The usual
1781 sequence is something like
1783 target nrom <netrom-hostname>
1785 target remote <netrom-hostname>:1235
1789 GDB now includes support for the Apple Macintosh, as a host only. It
1790 may be run as either an MPW tool or as a standalone application, and
1791 it can debug through the serial port. All the usual GDB commands are
1792 available, but to the target command, you must supply "serial" as the
1793 device type instead of "/dev/ttyXX". See mpw-README in the main
1794 directory for more information on how to build. The MPW configuration
1795 scripts */mpw-config.in support only a few targets, and only the
1796 mips-idt-ecoff target has been tested.
1800 GDB configuration now uses autoconf. This is not user-visible,
1801 but does simplify configuration and building.
1805 GDB now supports hpux10.
1807 *** Changes in GDB-4.14:
1809 * New native configurations
1811 x86 FreeBSD i[345]86-*-freebsd
1812 x86 NetBSD i[345]86-*-netbsd
1813 NS32k NetBSD ns32k-*-netbsd
1814 Sparc NetBSD sparc-*-netbsd
1818 A29K VxWorks a29k-*-vxworks
1819 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1820 CPU32 EST-300 emulator m68*-*-est*
1821 PowerPC ELF powerpc-*-elf
1824 * Alpha OSF/1 support for procfs
1826 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1827 possible to attach to running processes. As the mounting of the /proc
1828 filesystem is optional on the Alpha, GDB automatically determines
1829 the availability of /proc during startup. This can lead to problems
1830 if /proc is unmounted after GDB has been started.
1832 * Arguments to user-defined commands
1834 User commands may accept up to 10 arguments separated by whitespace.
1835 Arguments are accessed within the user command via $arg0..$arg9. A
1838 print $arg0 + $arg1 + $arg2
1840 To execute the command use:
1843 Defines the command "adder" which prints the sum of its three arguments.
1844 Note the arguments are text substitutions, so they may reference variables,
1845 use complex expressions, or even perform inferior function calls.
1847 * New `if' and `while' commands
1849 This makes it possible to write more sophisticated user-defined
1850 commands. Both commands take a single argument, which is the
1851 expression to evaluate, and must be followed by the commands to
1852 execute, one per line, if the expression is nonzero, the list being
1853 terminated by the word `end'. The `if' command list may include an
1854 `else' word, which causes the following commands to be executed only
1855 if the expression is zero.
1857 * Fortran source language mode
1859 GDB now includes partial support for Fortran 77. It will recognize
1860 Fortran programs and can evaluate a subset of Fortran expressions, but
1861 variables and functions may not be handled correctly. GDB will work
1862 with G77, but does not yet know much about symbols emitted by other
1865 * Better HPUX support
1867 Most debugging facilities now work on dynamic executables for HPPAs
1868 running hpux9 or later. You can attach to running dynamically linked
1869 processes, but by default the dynamic libraries will be read-only, so
1870 for instance you won't be able to put breakpoints in them. To change
1871 that behavior do the following before running the program:
1877 This will cause the libraries to be mapped private and read-write.
1878 To revert to the normal behavior, do this:
1884 You cannot set breakpoints or examine data in the library until after
1885 the library is loaded if the function/data symbols do not have
1888 GDB can now also read debug symbols produced by the HP C compiler on
1889 HPPAs (sorry, no C++, Fortran or 68k support).
1891 * Target byte order now dynamically selectable
1893 You can choose which byte order to use with a target system, via the
1894 commands "set endian big" and "set endian little", and you can see the
1895 current setting by using "show endian". You can also give the command
1896 "set endian auto", in which case GDB will use the byte order
1897 associated with the executable. Currently, only embedded MIPS
1898 configurations support dynamic selection of target byte order.
1900 * New DOS host serial code
1902 This version uses DPMI interrupts to handle buffered I/O, so you
1903 no longer need to run asynctsr when debugging boards connected to
1906 *** Changes in GDB-4.13:
1908 * New "complete" command
1910 This lists all the possible completions for the rest of the line, if it
1911 were to be given as a command itself. This is intended for use by emacs.
1913 * Trailing space optional in prompt
1915 "set prompt" no longer adds a space for you after the prompt you set. This
1916 allows you to set a prompt which ends in a space or one that does not.
1918 * Breakpoint hit counts
1920 "info break" now displays a count of the number of times the breakpoint
1921 has been hit. This is especially useful in conjunction with "ignore"; you
1922 can ignore a large number of breakpoint hits, look at the breakpoint info
1923 to see how many times the breakpoint was hit, then run again, ignoring one
1924 less than that number, and this will get you quickly to the last hit of
1927 * Ability to stop printing at NULL character
1929 "set print null-stop" will cause GDB to stop printing the characters of
1930 an array when the first NULL is encountered. This is useful when large
1931 arrays actually contain only short strings.
1933 * Shared library breakpoints
1935 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1936 breakpoints in shared libraries before the executable is run.
1938 * Hardware watchpoints
1940 There is a new hardware breakpoint for the watch command for sparclite
1941 targets. See gdb/sparclite/hw_breakpoint.note.
1943 Hardware watchpoints are also now supported under GNU/Linux.
1947 Annotations have been added. These are for use with graphical interfaces,
1948 and are still experimental. Currently only gdba.el uses these.
1950 * Improved Irix 5 support
1952 GDB now works properly with Irix 5.2.
1954 * Improved HPPA support
1956 GDB now works properly with the latest GCC and GAS.
1958 * New native configurations
1960 Sequent PTX4 i[34]86-sequent-ptx4
1961 HPPA running OSF/1 hppa*-*-osf*
1962 Atari TT running SVR4 m68*-*-sysv4*
1963 RS/6000 LynxOS rs6000-*-lynxos*
1967 OS/9000 i[34]86-*-os9k
1968 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1971 * Hitachi SH7000 and E7000-PC ICE support
1973 There is now support for communicating with the Hitachi E7000-PC ICE.
1974 This is available automatically when GDB is configured for the SH.
1978 As usual, a variety of small fixes and improvements, both generic
1979 and configuration-specific. See the ChangeLog for more detail.
1981 *** Changes in GDB-4.12:
1983 * Irix 5 is now supported
1987 GDB-4.12 on the HPPA has a number of changes which make it unable
1988 to debug the output from the currently released versions of GCC and
1989 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1990 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1991 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1994 *** Changes in GDB-4.11:
1996 * User visible changes:
2000 The "set remotedebug" option is now consistent between the mips remote
2001 target, remote targets using the gdb-specific protocol, UDI (AMD's
2002 debug protocol for the 29k) and the 88k bug monitor. It is now an
2003 integer specifying a debug level (normally 0 or 1, but 2 means more
2004 debugging info for the mips target).
2006 * DEC Alpha native support
2008 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2009 debug info, but GDB works fairly well with the DEC compiler and should
2010 work with a future GCC release. See the README file for a few
2011 Alpha-specific notes.
2013 * Preliminary thread implementation
2015 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2017 * LynxOS native and target support for 386
2019 This release has been hosted on LynxOS 2.2, and also can be configured
2020 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2023 * Improvements in C++ mangling/demangling.
2025 This release has much better g++ debugging, specifically in name
2026 mangling/demangling, virtual function calls, print virtual table,
2027 call methods, ...etc.
2029 *** Changes in GDB-4.10:
2031 * User visible changes:
2033 Remote debugging using the GDB-specific (`target remote') protocol now
2034 supports the `load' command. This is only useful if you have some
2035 other way of getting the stub to the target system, and you can put it
2036 somewhere in memory where it won't get clobbered by the download.
2038 Filename completion now works.
2040 When run under emacs mode, the "info line" command now causes the
2041 arrow to point to the line specified. Also, "info line" prints
2042 addresses in symbolic form (as well as hex).
2044 All vxworks based targets now support a user settable option, called
2045 vxworks-timeout. This option represents the number of seconds gdb
2046 should wait for responses to rpc's. You might want to use this if
2047 your vxworks target is, perhaps, a slow software simulator or happens
2048 to be on the far side of a thin network line.
2052 This release contains support for using a DEC alpha as a GDB host for
2053 cross debugging. Native alpha debugging is not supported yet.
2056 *** Changes in GDB-4.9:
2060 This is the first GDB release which is accompanied by a matching testsuite.
2061 The testsuite requires installation of dejagnu, which should be available
2062 via ftp from most sites that carry GNU software.
2066 'Cfront' style demangling has had its name changed to 'ARM' style, to
2067 emphasize that it was written from the specifications in the C++ Annotated
2068 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2069 disclaimers, it still generated too much confusion with users attempting to
2070 use gdb with AT&T cfront.
2074 GDB now uses a standard remote interface to a simulator library.
2075 So far, the library contains simulators for the Zilog Z8001/2, the
2076 Hitachi H8/300, H8/500 and Super-H.
2078 * New targets supported
2080 H8/300 simulator h8300-hitachi-hms or h8300hms
2081 H8/500 simulator h8500-hitachi-hms or h8500hms
2082 SH simulator sh-hitachi-hms or sh
2083 Z8000 simulator z8k-zilog-none or z8ksim
2084 IDT MIPS board over serial line mips-idt-ecoff
2086 Cross-debugging to GO32 targets is supported. It requires a custom
2087 version of the i386-stub.c module which is integrated with the
2088 GO32 memory extender.
2090 * New remote protocols
2092 MIPS remote debugging protocol.
2094 * New source languages supported
2096 This version includes preliminary support for Chill, a Pascal like language
2097 used by telecommunications companies. Chill support is also being integrated
2098 into the GNU compiler, but we don't know when it will be publically available.
2101 *** Changes in GDB-4.8:
2103 * HP Precision Architecture supported
2105 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2106 version of this support was available as a set of patches from the
2107 University of Utah. GDB does not support debugging of programs
2108 compiled with the HP compiler, because HP will not document their file
2109 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2110 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2112 Many problems in the preliminary version have been fixed.
2114 * Faster and better demangling
2116 We have improved template demangling and fixed numerous bugs in the GNU style
2117 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2118 character types (wchar_t) are now supported. Demangling of each symbol is now
2119 only done once, and is cached when the symbol table for a file is read in.
2120 This results in a small increase in memory usage for C programs, a moderate
2121 increase in memory usage for C++ programs, and a fantastic speedup in
2124 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2125 from the specifications in the Annotated Reference Manual, which AT&T's
2126 compiler does not actually implement.
2128 * G++ multiple inheritance compiler problem
2130 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2131 inheritance lattices was reworked to properly discover ambiguities. We
2132 recently found an example which causes this new algorithm to fail in a
2133 very subtle way, producing bad debug information for those classes.
2134 The file 'gcc.patch' (in this directory) can be applied to gcc to
2135 circumvent the problem. A future GCC release will contain a complete
2138 The previous G++ debug info problem (mentioned below for the gdb-4.7
2139 release) is fixed in gcc version 2.3.2.
2141 * Improved configure script
2143 The `configure' script will now attempt to guess your system type if
2144 you don't supply a host system type. The old scheme of supplying a
2145 host system triplet is preferable over using this. All the magic is
2146 done in the new `config.guess' script. Examine it for details.
2148 We have also brought our configure script much more in line with the FSF's
2149 version. It now supports the --with-xxx options. In particular,
2150 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2151 The resulting GDB will not be able to read arbitrary object file formats --
2152 only the format ``expected'' to be used on the configured target system.
2153 We hope to make this the default in a future release.
2155 * Documentation improvements
2157 There's new internal documentation on how to modify GDB, and how to
2158 produce clean changes to the code. We implore people to read it
2159 before submitting changes.
2161 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2162 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2163 `info' files are also provided. To build `info' files from scratch,
2164 you will need the latest `makeinfo' release, which will be available in
2165 a future texinfo-X.Y release.
2167 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2168 We're not sure exactly which versions have this problem, but it has
2169 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2170 or better. If that isn't possible, there is a patch in
2171 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2172 around this problem.
2176 GDB now supports array constants that can be used in expressions typed in by
2177 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2178 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2181 The new directory `gdb/sparclite' contains a program that demonstrates
2182 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2184 * New native hosts supported
2186 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2187 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2189 * New targets supported
2191 AMD 29k family via UDI a29k-amd-udi or udi29k
2193 * New file formats supported
2195 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2196 HPUX core files, and SCO 3.2v2 core files.
2200 Attaching to processes now works again; thanks for the many bug reports.
2202 We have also stomped on a bunch of core dumps caused by
2203 printf_filtered("%s") problems.
2205 We eliminated a copyright problem on the rpc and ptrace header files
2206 for VxWorks, which was discovered at the last minute during the 4.7
2207 release. You should now be able to build a VxWorks GDB.
2209 You can now interrupt gdb while an attached process is running. This
2210 will cause the attached process to stop, and give control back to GDB.
2212 We fixed problems caused by using too many file descriptors
2213 for reading symbols from object files and libraries. This was
2214 especially a problem for programs that used many (~100) shared
2217 The `step' command now only enters a subroutine if there is line number
2218 information for the subroutine. Otherwise it acts like the `next'
2219 command. Previously, `step' would enter subroutines if there was
2220 any debugging information about the routine. This avoids problems
2221 when using `cc -g1' on MIPS machines.
2223 * Internal improvements
2225 GDB's internal interfaces have been improved to make it easier to support
2226 debugging of multiple languages in the future.
2228 GDB now uses a common structure for symbol information internally.
2229 Minimal symbols (derived from linkage symbols in object files), partial
2230 symbols (from a quick scan of debug information), and full symbols
2231 contain a common subset of information, making it easier to write
2232 shared code that handles any of them.
2234 * New command line options
2236 We now accept --silent as an alias for --quiet.
2240 The memory-mapped-malloc library is now licensed under the GNU Library
2241 General Public License.
2243 *** Changes in GDB-4.7:
2245 * Host/native/target split
2247 GDB has had some major internal surgery to untangle the support for
2248 hosts and remote targets. Now, when you configure GDB for a remote
2249 target, it will no longer load in all of the support for debugging
2250 local programs on the host. When fully completed and tested, this will
2251 ensure that arbitrary host/target combinations are possible.
2253 The primary conceptual shift is to separate the non-portable code in
2254 GDB into three categories. Host specific code is required any time GDB
2255 is compiled on that host, regardless of the target. Target specific
2256 code relates to the peculiarities of the target, but can be compiled on
2257 any host. Native specific code is everything else: it can only be
2258 built when the host and target are the same system. Child process
2259 handling and core file support are two common `native' examples.
2261 GDB's use of /proc for controlling Unix child processes is now cleaner.
2262 It has been split out into a single module under the `target_ops' vector,
2263 plus two native-dependent functions for each system that uses /proc.
2265 * New hosts supported
2267 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2268 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2269 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2271 * New targets supported
2273 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2274 68030 and CPU32 m68030-*-*, m68332-*-*
2276 * New native hosts supported
2278 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2279 (386bsd is not well tested yet)
2280 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2282 * New file formats supported
2284 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2285 supports reading of `a.out.adobe' object files, which are an a.out
2286 format extended with minimal information about multiple sections.
2290 `show copying' is the same as the old `info copying'.
2291 `show warranty' is the same as `info warrantee'.
2292 These were renamed for consistency. The old commands continue to work.
2294 `info handle' is a new alias for `info signals'.
2296 You can now define pre-command hooks, which attach arbitrary command
2297 scripts to any command. The commands in the hook will be executed
2298 prior to the user's command. You can also create a hook which will be
2299 executed whenever the program stops. See gdb.texinfo.
2303 We now deal with Cfront style name mangling, and can even extract type
2304 info from mangled symbols. GDB can automatically figure out which
2305 symbol mangling style your C++ compiler uses.
2307 Calling of methods and virtual functions has been improved as well.
2311 The crash that occured when debugging Sun Ansi-C compiled binaries is
2312 fixed. This was due to mishandling of the extra N_SO stabs output
2315 We also finally got Ultrix 4.2 running in house, and fixed core file
2316 support, with help from a dozen people on the net.
2318 John M. Farrell discovered that the reason that single-stepping was so
2319 slow on all of the Mips based platforms (primarily SGI and DEC) was
2320 that we were trying to demangle and lookup a symbol used for internal
2321 purposes on every instruction that was being stepped through. Changing
2322 the name of that symbol so that it couldn't be mistaken for a C++
2323 mangled symbol sped things up a great deal.
2325 Rich Pixley sped up symbol lookups in general by getting much smarter
2326 about when C++ symbol mangling is necessary. This should make symbol
2327 completion (TAB on the command line) much faster. It's not as fast as
2328 we'd like, but it's significantly faster than gdb-4.6.
2332 A new user controllable variable 'call_scratch_address' can
2333 specify the location of a scratch area to be used when GDB
2334 calls a function in the target. This is necessary because the
2335 usual method of putting the scratch area on the stack does not work
2336 in systems that have separate instruction and data spaces.
2338 We integrated changes to support the 29k UDI (Universal Debugger
2339 Interface), but discovered at the last minute that we didn't have all
2340 of the appropriate copyright paperwork. We are working with AMD to
2341 resolve this, and hope to have it available soon.
2345 We have sped up the remote serial line protocol, especially for targets
2346 with lots of registers. It now supports a new `expedited status' ('T')
2347 message which can be used in place of the existing 'S' status message.
2348 This allows the remote stub to send only the registers that GDB
2349 needs to make a quick decision about single-stepping or conditional
2350 breakpoints, eliminating the need to fetch the entire register set for
2351 each instruction being stepped through.
2353 The GDB remote serial protocol now implements a write-through cache for
2354 registers, only re-reading the registers if the target has run.
2356 There is also a new remote serial stub for SPARC processors. You can
2357 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2358 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2359 processor with a serial port.
2363 Configure.in files have become much easier to read and modify. A new
2364 `table driven' format makes it more obvious what configurations are
2365 supported, and what files each one uses.
2369 There is a new opcodes library which will eventually contain all of the
2370 disassembly routines and opcode tables. At present, it only contains
2371 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2372 disassembler (binutils/objdump) to share these routines.
2374 The libiberty library is now copylefted under the GNU Library General
2375 Public License. This allows more liberal use, and was done so libg++
2376 can use it. This makes no difference to GDB, since the Library License
2377 grants all the rights from the General Public License.
2381 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2382 reference to the stabs symbol info used by the debugger. It is (as far
2383 as we know) the only published document on this fascinating topic. We
2384 encourage you to read it, compare it to the stabs information on your
2385 system, and send improvements on the document in general (to
2386 bug-gdb@prep.ai.mit.edu).
2388 And, of course, many bugs have been fixed.
2391 *** Changes in GDB-4.6:
2393 * Better support for C++ function names
2395 GDB now accepts as input the "demangled form" of C++ overloaded function
2396 names and member function names, and can do command completion on such names
2397 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2398 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2399 Make use of command completion, it is your friend.
2401 GDB also now accepts a variety of C++ mangled symbol formats. They are
2402 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2403 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2404 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2405 for the list of formats.
2407 * G++ symbol mangling problem
2409 Recent versions of gcc have a bug in how they emit debugging information for
2410 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2411 directory) can be applied to gcc to fix the problem. Alternatively, if you
2412 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2413 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2414 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2417 * New 'maintenance' command
2419 All of the commands related to hacking GDB internals have been moved out of
2420 the main command set, and now live behind the 'maintenance' command. This
2421 can also be abbreviated as 'mt'. The following changes were made:
2423 dump-me -> maintenance dump-me
2424 info all-breakpoints -> maintenance info breakpoints
2425 printmsyms -> maintenance print msyms
2426 printobjfiles -> maintenance print objfiles
2427 printpsyms -> maintenance print psymbols
2428 printsyms -> maintenance print symbols
2430 The following commands are new:
2432 maintenance demangle Call internal GDB demangler routine to
2433 demangle a C++ link name and prints the result.
2434 maintenance print type Print a type chain for a given symbol
2436 * Change to .gdbinit file processing
2438 We now read the $HOME/.gdbinit file before processing the argv arguments
2439 (e.g. reading symbol files or core files). This allows global parameters to
2440 be set, which will apply during the symbol reading. The ./.gdbinit is still
2441 read after argv processing.
2443 * New hosts supported
2445 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
2447 GNU/Linux support i386-unknown-linux or linux
2449 We are also including code to support the HP/PA running BSD and HPUX. This
2450 is almost guaranteed not to work, as we didn't have time to test or build it
2451 for this release. We are including it so that the more adventurous (or
2452 masochistic) of you can play with it. We also had major problems with the
2453 fact that the compiler that we got from HP doesn't support the -g option.
2456 * New targets supported
2458 Hitachi H8/300 h8300-hitachi-hms or h8300hms
2460 * More smarts about finding #include files
2462 GDB now remembers the compilation directory for all include files, and for
2463 all files from which C is generated (like yacc and lex sources). This
2464 greatly improves GDB's ability to find yacc/lex sources, and include files,
2465 especially if you are debugging your program from a directory different from
2466 the one that contains your sources.
2468 We also fixed a bug which caused difficulty with listing and setting
2469 breakpoints in include files which contain C code. (In the past, you had to
2470 try twice in order to list an include file that you hadn't looked at before.)
2472 * Interesting infernals change
2474 GDB now deals with arbitrary numbers of sections, where the symbols for each
2475 section must be relocated relative to that section's landing place in the
2476 target's address space. This work was needed to support ELF with embedded
2477 stabs used by Solaris-2.0.
2479 * Bug fixes (of course!)
2481 There have been loads of fixes for the following things:
2482 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2483 i960, stabs, DOS(GO32), procfs, etc...
2485 See the ChangeLog for details.
2487 *** Changes in GDB-4.5:
2489 * New machines supported (host and target)
2491 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2493 SGI Irix-4.x mips-sgi-irix4 or iris4
2495 * New malloc package
2497 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2498 Mmalloc is capable of handling mutiple heaps of memory. It is also
2499 capable of saving a heap to a file, and then mapping it back in later.
2500 This can be used to greatly speedup the startup of GDB by using a
2501 pre-parsed symbol table which lives in a mmalloc managed heap. For
2502 more details, please read mmalloc/mmalloc.texi.
2506 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2507 'help info proc' for details.
2509 * MIPS ecoff symbol table format
2511 The code that reads MIPS symbol table format is now supported on all hosts.
2512 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2515 * File name changes for MS-DOS
2517 Many files in the config directories have been renamed to make it easier to
2518 support GDB on MS-DOSe systems (which have very restrictive file name
2519 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2520 environment) is close to working but has some remaining problems. Note
2521 that debugging of DOS programs is not supported, due to limitations
2522 in the ``operating system'', but it can be used to host cross-debugging.
2524 * Cross byte order fixes
2526 Many fixes have been made to support cross debugging of Sparc and MIPS
2527 targets from hosts whose byte order differs.
2529 * New -mapped and -readnow options
2531 If memory-mapped files are available on your system through the 'mmap'
2532 system call, you can use the -mapped option on the `file' or
2533 `symbol-file' commands to cause GDB to write the symbols from your
2534 program into a reusable file. If the program you are debugging is
2535 called `/path/fred', the mapped symbol file will be `./fred.syms'.
2536 Future GDB debugging sessions will notice the presence of this file,
2537 and will quickly map in symbol information from it, rather than reading
2538 the symbol table from the executable program. Using the '-mapped'
2539 option in a GDB `file' or `symbol-file' command has the same effect as
2540 starting GDB with the '-mapped' command-line option.
2542 You can cause GDB to read the entire symbol table immediately by using
2543 the '-readnow' option with any of the commands that load symbol table
2544 information (or on the GDB command line). This makes the command
2545 slower, but makes future operations faster.
2547 The -mapped and -readnow options are typically combined in order to
2548 build a `fred.syms' file that contains complete symbol information.
2549 A simple GDB invocation to do nothing but build a `.syms' file for future
2552 gdb -batch -nx -mapped -readnow programname
2554 The `.syms' file is specific to the host machine on which GDB is run.
2555 It holds an exact image of GDB's internal symbol table. It cannot be
2556 shared across multiple host platforms.
2558 * longjmp() handling
2560 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2561 siglongjmp() without losing control. This feature has not yet been ported to
2562 all systems. It currently works on many 386 platforms, all MIPS-based
2563 platforms (SGI, DECstation, etc), and Sun3/4.
2567 Preliminary work has been put in to support the new Solaris OS from Sun. At
2568 this time, it can control and debug processes, but it is not capable of
2573 As always, many many bug fixes. The major areas were with g++, and mipsread.
2574 People using the MIPS-based platforms should experience fewer mysterious
2575 crashes and trashed symbol tables.
2577 *** Changes in GDB-4.4:
2579 * New machines supported (host and target)
2581 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2583 BSD Reno on Vax vax-dec-bsd
2584 Ultrix on Vax vax-dec-ultrix
2586 * New machines supported (target)
2588 AMD 29000 embedded, using EBMON a29k-none-none
2592 GDB continues to improve its handling of C++. `References' work better.
2593 The demangler has also been improved, and now deals with symbols mangled as
2594 per the Annotated C++ Reference Guide.
2596 GDB also now handles `stabs' symbol information embedded in MIPS
2597 `ecoff' symbol tables. Since the ecoff format was not easily
2598 extensible to handle new languages such as C++, this appeared to be a
2599 good way to put C++ debugging info into MIPS binaries. This option
2600 will be supported in the GNU C compiler, version 2, when it is
2603 * New features for SVR4
2605 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2606 shared libraries. Debugging dynamically linked programs should present
2607 only minor differences from debugging statically linked programs.
2609 The `info proc' command will print out information about any process
2610 on an SVR4 system (including the one you are debugging). At the moment,
2611 it prints the address mappings of the process.
2613 If you bring up GDB on another SVR4 system, please send mail to
2614 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2616 * Better dynamic linking support in SunOS
2618 Reading symbols from shared libraries which contain debugging symbols
2619 now works properly. However, there remain issues such as automatic
2620 skipping of `transfer vector' code during function calls, which
2621 make it harder to debug code in a shared library, than to debug the
2622 same code linked statically.
2626 GDB is now using the latest `getopt' routines from the FSF. This
2627 version accepts the -- prefix for options with long names. GDB will
2628 continue to accept the old forms (-option and +option) as well.
2629 Various single letter abbreviations for options have been explicity
2630 added to the option table so that they won't get overshadowed in the
2631 future by other options that begin with the same letter.
2635 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2636 Many assorted bugs have been handled. Many more remain to be handled.
2637 See the various ChangeLog files (primarily in gdb and bfd) for details.
2640 *** Changes in GDB-4.3:
2642 * New machines supported (host and target)
2644 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2645 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2646 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2648 * Almost SCO Unix support
2650 We had hoped to support:
2651 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2652 (except for core file support), but we discovered very late in the release
2653 that it has problems with process groups that render gdb unusable. Sorry
2654 about that. I encourage people to fix it and post the fixes.
2656 * Preliminary ELF and DWARF support
2658 GDB can read ELF object files on System V Release 4, and can handle
2659 debugging records for C, in DWARF format, in ELF files. This support
2660 is preliminary. If you bring up GDB on another SVR4 system, please
2661 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2666 GDB now uses the latest `readline' library. One user-visible change
2667 is that two tabs will list possible command completions, which previously
2668 required typing M-? (meta-question mark, or ESC ?).
2672 The `stepi' bug that many of you noticed has been squashed.
2673 Many bugs in C++ have been handled. Many more remain to be handled.
2674 See the various ChangeLog files (primarily in gdb and bfd) for details.
2676 * State of the MIPS world (in case you wondered):
2678 GDB can understand the symbol tables emitted by the compilers
2679 supplied by most vendors of MIPS-based machines, including DEC. These
2680 symbol tables are in a format that essentially nobody else uses.
2682 Some versions of gcc come with an assembler post-processor called
2683 mips-tfile. This program is required if you want to do source-level
2684 debugging of gcc-compiled programs. I believe FSF does not ship
2685 mips-tfile with gcc version 1, but it will eventually come with gcc
2688 Debugging of g++ output remains a problem. g++ version 1.xx does not
2689 really support it at all. (If you're lucky, you should be able to get
2690 line numbers and stack traces to work, but no parameters or local
2691 variables.) With some work it should be possible to improve the
2694 When gcc version 2 is released, you will have somewhat better luck.
2695 However, even then you will get confusing results for inheritance and
2698 We will eventually provide full debugging of g++ output on
2699 DECstations. This will probably involve some kind of stabs-in-ecoff
2700 encapulation, but the details have not been worked out yet.
2703 *** Changes in GDB-4.2:
2705 * Improved configuration
2707 Only one copy of `configure' exists now, and it is not self-modifying.
2708 Porting BFD is simpler.
2712 The `step' and `next' commands now only stop at the first instruction
2713 of a source line. This prevents the multiple stops that used to occur
2714 in switch statements, for-loops, etc. `Step' continues to stop if a
2715 function that has debugging information is called within the line.
2719 Lots of small bugs fixed. More remain.
2721 * New host supported (not target)
2723 Intel 386 PC clone running Mach i386-none-mach
2726 *** Changes in GDB-4.1:
2728 * Multiple source language support
2730 GDB now has internal scaffolding to handle several source languages.
2731 It determines the type of each source file from its filename extension,
2732 and will switch expression parsing and number formatting to match the
2733 language of the function in the currently selected stack frame.
2734 You can also specifically set the language to be used, with
2735 `set language c' or `set language modula-2'.
2739 GDB now has preliminary support for the GNU Modula-2 compiler,
2740 currently under development at the State University of New York at
2741 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2742 continue through the fall of 1991 and into 1992.
2744 Other Modula-2 compilers are currently not supported, and attempting to
2745 debug programs compiled with them will likely result in an error as the
2746 symbol table is read. Feel free to work on it, though!
2748 There are hooks in GDB for strict type checking and range checking,
2749 in the `Modula-2 philosophy', but they do not currently work.
2753 GDB can now write to executable and core files (e.g. patch
2754 a variable's value). You must turn this switch on, specify
2755 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2756 by assigning a new value to a variable. Modifications take
2759 * Automatic SunOS shared library reading
2761 When you run your program, GDB automatically determines where its
2762 shared libraries (if any) have been loaded, and reads their symbols.
2763 The `share' command is no longer needed. This also works when
2764 examining core files.
2768 You can specify the number of lines that the `list' command shows.
2771 * New machines supported (host and target)
2773 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2774 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2775 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2777 * New hosts supported (not targets)
2779 IBM RT/PC: romp-ibm-aix or rtpc
2781 * New targets supported (not hosts)
2783 AMD 29000 embedded with COFF a29k-none-coff
2784 AMD 29000 embedded with a.out a29k-none-aout
2785 Ultracomputer remote kernel debug a29k-nyu-kern
2787 * New remote interfaces
2793 *** Changes in GDB-4.0:
2797 Wide output is wrapped at good places to make the output more readable.
2799 Gdb now supports cross-debugging from a host machine of one type to a
2800 target machine of another type. Communication with the target system
2801 is over serial lines. The ``target'' command handles connecting to the
2802 remote system; the ``load'' command will download a program into the
2803 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2804 also supports debugging of realtime processes running under VxWorks,
2805 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2806 stub on the target system.
2808 New CPUs supported include the AMD 29000 and Intel 960.
2810 GDB now reads object files and symbol tables via a ``binary file''
2811 library, which allows a single copy of GDB to debug programs of multiple
2812 object file types such as a.out and coff.
2814 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2815 refcard.dvi and refcard.ps are available to format it).
2818 * Control-Variable user interface simplified
2820 All variables that control the operation of the debugger can be set
2821 by the ``set'' command, and displayed by the ``show'' command.
2823 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2824 ``Show prompt'' produces the response:
2825 Gdb's prompt is new-gdb=>.
2827 What follows are the NEW set commands. The command ``help set'' will
2828 print a complete list of old and new set commands. ``help set FOO''
2829 will give a longer description of the variable FOO. ``show'' will show
2830 all of the variable descriptions and their current settings.
2832 confirm on/off: Enables warning questions for operations that are
2833 hard to recover from, e.g. rerunning the program while
2834 it is already running. Default is ON.
2836 editing on/off: Enables EMACS style command line editing
2837 of input. Previous lines can be recalled with
2838 control-P, the current line can be edited with control-B,
2839 you can search for commands with control-R, etc.
2842 history filename NAME: NAME is where the gdb command history
2843 will be stored. The default is .gdb_history,
2844 or the value of the environment variable
2847 history size N: The size, in commands, of the command history. The
2848 default is 256, or the value of the environment variable
2851 history save on/off: If this value is set to ON, the history file will
2852 be saved after exiting gdb. If set to OFF, the
2853 file will not be saved. The default is OFF.
2855 history expansion on/off: If this value is set to ON, then csh-like
2856 history expansion will be performed on
2857 command line input. The default is OFF.
2859 radix N: Sets the default radix for input and output. It can be set
2860 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2861 in the current radix, so "set radix 10" is always a no-op.
2863 height N: This integer value is the number of lines on a page. Default
2864 is 24, the current `stty rows'' setting, or the ``li#''
2865 setting from the termcap entry matching the environment
2868 width N: This integer value is the number of characters on a line.
2869 Default is 80, the current `stty cols'' setting, or the ``co#''
2870 setting from the termcap entry matching the environment
2873 Note: ``set screensize'' is obsolete. Use ``set height'' and
2874 ``set width'' instead.
2876 print address on/off: Print memory addresses in various command displays,
2877 such as stack traces and structure values. Gdb looks
2878 more ``symbolic'' if you turn this off; it looks more
2879 ``machine level'' with it on. Default is ON.
2881 print array on/off: Prettyprint arrays. New convenient format! Default
2884 print demangle on/off: Print C++ symbols in "source" form if on,
2887 print asm-demangle on/off: Same, for assembler level printouts
2890 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2893 * Support for Epoch Environment.
2895 The epoch environment is a version of Emacs v18 with windowing. One
2896 new command, ``inspect'', is identical to ``print'', except that if you
2897 are running in the epoch environment, the value is printed in its own
2901 * Support for Shared Libraries
2903 GDB can now debug programs and core files that use SunOS shared libraries.
2904 Symbols from a shared library cannot be referenced
2905 before the shared library has been linked with the program (this
2906 happens after you type ``run'' and before the function main() is entered).
2907 At any time after this linking (including when examining core files
2908 from dynamically linked programs), gdb reads the symbols from each
2909 shared library when you type the ``sharedlibrary'' command.
2910 It can be abbreviated ``share''.
2912 sharedlibrary REGEXP: Load shared object library symbols for files
2913 matching a unix regular expression. No argument
2914 indicates to load symbols for all shared libraries.
2916 info sharedlibrary: Status of loaded shared libraries.
2921 A watchpoint stops execution of a program whenever the value of an
2922 expression changes. Checking for this slows down execution
2923 tremendously whenever you are in the scope of the expression, but is
2924 quite useful for catching tough ``bit-spreader'' or pointer misuse
2925 problems. Some machines such as the 386 have hardware for doing this
2926 more quickly, and future versions of gdb will use this hardware.
2928 watch EXP: Set a watchpoint (breakpoint) for an expression.
2930 info watchpoints: Information about your watchpoints.
2932 delete N: Deletes watchpoint number N (same as breakpoints).
2933 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2934 enable N: Re-enables watchpoint number N (same as breakpoints).
2937 * C++ multiple inheritance
2939 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2942 * C++ exception handling
2944 Gdb now supports limited C++ exception handling. Besides the existing
2945 ability to breakpoint on an exception handler, gdb can breakpoint on
2946 the raising of an exception (before the stack is peeled back to the
2949 catch FOO: If there is a FOO exception handler in the dynamic scope,
2950 set a breakpoint to catch exceptions which may be raised there.
2951 Multiple exceptions (``catch foo bar baz'') may be caught.
2953 info catch: Lists all exceptions which may be caught in the
2954 current stack frame.
2957 * Minor command changes
2959 The command ``call func (arg, arg, ...)'' now acts like the print
2960 command, except it does not print or save a value if the function's result
2961 is void. This is similar to dbx usage.
2963 The ``up'' and ``down'' commands now always print the frame they end up
2964 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2965 frames without printing.
2967 * New directory command
2969 'dir' now adds directories to the FRONT of the source search path.
2970 The path starts off empty. Source files that contain debug information
2971 about the directory in which they were compiled can be found even
2972 with an empty path; Sun CC and GCC include this information. If GDB can't
2973 find your source file in the current directory, type "dir .".
2975 * Configuring GDB for compilation
2977 For normal use, type ``./configure host''. See README or gdb.texinfo
2980 GDB now handles cross debugging. If you are remotely debugging between
2981 two different machines, type ``./configure host -target=targ''.
2982 Host is the machine where GDB will run; targ is the machine
2983 where the program that you are debugging will run.