1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * GDB now supports automatic retrieval of shared library files from
7 remote targets. To use this feature, specify a system root that begins
8 with the `remote:' prefix, either via the `set sysroot' command or via
9 the `--with-sysroot' configure-time option.
11 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
12 now complete on file names.
14 * When completing in expressions, gdb will attempt to limit
15 completions to allowable structure or union fields, where appropriate.
16 For instance, consider:
18 # struct example { int f1; double f2; };
19 # struct example variable;
22 If the user types TAB at the end of this command line, the available
23 completions will be "f1" and "f2".
25 * GDB now supports the token-splicing (##) and stringification (#)
26 operators when expanding macros. It also supports variable-arity
32 Search memory for a sequence of bytes.
35 Turn off `+'/`-' protocol acknowledgments to permit more efficient
36 operation over reliable transport links. Use of this packet is
37 controlled by the `set remote noack-packet' command.
40 Obtains additional operating system information
42 * Removed remote protocol undocumented extension
44 An undocumented extension to the remote protocol's `S' stop reply
45 packet that permited the stub to pass a process id was removed.
46 Remote servers should use the `T' stop reply packet instead.
48 * The "disassemble" command now supports an optional /m modifier to print mixed
51 * GDB now supports multiple function calling conventions according to the
52 DWARF-2 DW_AT_calling_convention function attribute.
54 * The SH target utilizes the aforementioned change to distinguish between gcc
55 and Renesas calling convention. It also adds the new CLI commands
56 `set/show sh calling-convention'.
58 * GDB can now read compressed debug sections, as produced by GNU gold
59 with the --compress-debug-sections=zlib flag.
61 * 64-bit core files are now supported on AIX.
63 * Thread switching is now supported on Tru64.
65 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
66 which will be allocated using malloc later in program execution.
68 * The qXfer:libraries:read remote procotol packet now allows passing a
69 list of section offsets.
71 * On GNU/Linux, GDB can now attach to stopped processes. Several race
72 conditions handling signals delivered during attach or thread creation
75 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
76 From the user's standpoint, all unqualified instances of True and False
77 are treated as the standard definitions, regardless of context.
79 * New features in the GDB remote stub, gdbserver
81 - The "--wrapper" command-line argument tells gdbserver to use a
82 wrapper program to launch programs for debugging.
84 - On PowerPC and S/390 targets, it is now possible to use a single
85 gdbserver executable to debug both 32-bit and 64-bit programs.
86 (This requires gdbserver itself to be built as a 64-bit executable.)
88 - gdbserver uses the new noack protocol mode for TCP connections to
89 reduce communications latency, if also supported and enabled in GDB.
91 - Support for the sparc64-linux-gnu target is now included in
96 GDB now has support for scripting using Python. Whether this is
97 available is determined at configure time.
101 Ada tasks can now be inspected in GDB. The following commands have
105 Print the list of Ada tasks.
107 Print detailed information about task number N.
109 Print the task number of the current task.
111 Switch the context of debugging to task number N.
115 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
117 Search memory for a sequence of bytes.
119 maint set python print-stack
120 maint show python print-stack
121 Show a stack trace when an error is encountered in a Python script.
124 Invoke CODE by passing it to the Python interpreter.
126 set print symbol-loading
127 show print symbol-loading
128 Control printing of symbol loading messages.
132 Display timestamps with GDB debugging output.
137 Use a wrapper program to launch programs for debugging.
139 set multiple-symbols (all|ask|cancel)
140 show multiple-symbols
141 The value of this variable can be changed to adjust the debugger behavior
142 when an expression or a breakpoint location contains an ambiguous symbol
143 name (an overloaded function name, for instance).
145 set breakpoint always-inserted
146 show breakpoint always-inserted
147 Keep breakpoints always inserted in the target, as opposed to inserting
148 them when resuming the target, and removing them when the target stops.
149 This option can improve debugger performance on slow remote targets.
151 set arm fallback-mode (arm|thumb|auto)
152 show arm fallback-mode
153 set arm force-mode (arm|thumb|auto)
155 These commands control how ARM GDB determines whether instructions
156 are ARM or Thumb. The default for both settings is auto, which uses
157 the current CPSR value for instructions without symbols; previous
158 versions of GDB behaved as if "set arm fallback-mode arm".
160 set disable-randomization
161 show disable-randomization
162 Standalone programs run with the virtual address space randomization enabled
163 by default on some platforms. This option keeps the addresses stable across
164 multiple debugging sessions.
167 Requests that asynchronous execution is enabled in the target, if available.
168 In this case, it's possible to resume target in the background, and interact
169 with GDB while the target is running. "show target-async" displays the
170 current state of asynchronous execution of the target.
172 set tcp auto-retry (on|off)
174 set tcp connect-timeout
175 show tcp connect-timeout
176 These commands allow GDB to retry failed TCP connections to a remote stub
177 with a specified timeout period; this is useful if the stub is launched
178 in parallel with GDB but may not be ready to accept connections immediately.
183 These allow macros to be defined, undefined, and listed
186 * New native configurations
188 x86/x86_64 Darwin i[34567]86-*-darwin*
191 Show operating system information about processes.
195 x86 DICOS i[34567]86-*-dicos*
201 These commands were actually not implemented on any target.
203 *** Changes in GDB 6.8
205 * New native configurations
207 NetBSD/hppa hppa*-*netbsd*
208 Xtensa GNU/Linux xtensa*-*-linux*
212 NetBSD/hppa hppa*-*-netbsd*
213 Xtensa GNU/Lunux xtensa*-*-linux*
215 * Change in command line behavior -- corefiles vs. process ids.
217 When the '-p NUMBER' or '--pid NUMBER' options are used, and
218 attaching to process NUMBER fails, GDB no longer attempts to open a
219 core file named NUMBER. Attaching to a program using the -c option
220 is no longer supported. Instead, use the '-p' or '--pid' options.
222 * GDB can now be built as a native debugger for debugging Windows x86
223 (mingw32) Portable Executable (PE) programs.
225 * Pending breakpoints no longer change their number when their address
228 * GDB now supports breakpoints with multiple locations,
229 including breakpoints on C++ constructors, inside C++ templates,
230 and in inlined functions.
232 * GDB's ability to debug optimized code has been improved. GDB more
233 accurately identifies function bodies and lexical blocks that occupy
234 more than one contiguous range of addresses.
236 * Target descriptions can now describe registers for PowerPC.
238 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
239 registers on PowerPC targets.
241 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
242 targets even when the libthread_db library is not available.
244 * The GDB remote stub, gdbserver, now supports the new file transfer
245 commands (remote put, remote get, and remote delete).
247 * The GDB remote stub, gdbserver, now supports run and attach in
248 extended-remote mode.
250 * hppa*64*-*-hpux11* target broken
251 The debugger is unable to start a program and fails with the following
252 error: "Error trying to get information about dynamic linker".
253 The gdb-6.7 release is also affected.
255 * GDB now supports the --enable-targets= configure option to allow
256 building a single GDB executable that supports multiple remote
257 target architectures.
259 * GDB now supports debugging C and C++ programs which use the
260 Decimal Floating Point extension. In addition, the PowerPC target
261 now has a set of pseudo-registers to inspect decimal float values
262 stored in two consecutive float registers.
264 * The -break-insert MI command can optionally create pending
267 * Improved support for debugging Ada
268 Many improvements to the Ada language support have been made. These
270 - Better support for Ada2005 interface types
271 - Improved handling of arrays and slices in general
272 - Better support for Taft-amendment types
273 - The '{type} ADDRESS' expression is now allowed on the left hand-side
275 - Improved command completion in Ada
278 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
283 set print frame-arguments (all|scalars|none)
284 show print frame-arguments
285 The value of this variable can be changed to control which argument
286 values should be printed by the debugger when displaying a frame.
291 Transfer files to and from a remote target, and delete remote files.
298 Transfer files to and from a remote target, and delete remote files.
307 Open, close, read, write, and delete files on the remote system.
310 Attach to an existing process on the remote system, in extended-remote
314 Run a new process on the remote system, in extended-remote mode.
316 *** Changes in GDB 6.7
318 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
319 bfd, libiberty and opcodes, as revealed by static analysis donated by
320 Coverity, Inc. (http://scan.coverity.com).
322 * When looking up multiply-defined global symbols, GDB will now prefer the
323 symbol definition in the current shared library if it was built using the
324 -Bsymbolic linker option.
326 * When the Text User Interface (TUI) is not configured, GDB will now
327 recognize the -tui command-line option and print a message that the TUI
330 * The GDB remote stub, gdbserver, now has lower overhead for high
331 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
333 * GDB for MIPS targets now autodetects whether a remote target provides
334 32-bit or 64-bit register values.
336 * Support for C++ member pointers has been improved.
338 * GDB now understands XML target descriptions, which specify the
339 target's overall architecture. GDB can read a description from
340 a local file or over the remote serial protocol.
342 * Vectors of single-byte data use a new integer type which is not
343 automatically displayed as character or string data.
345 * The /s format now works with the print command. It displays
346 arrays of single-byte integers and pointers to single-byte integers
349 * Target descriptions can now describe target-specific registers,
350 for architectures which have implemented the support (currently
351 only ARM, M68K, and MIPS).
353 * GDB and the GDB remote stub, gdbserver, now support the XScale
356 * The GDB remote stub, gdbserver, has been updated to support
357 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
358 has been rewritten to use the standard GDB remote protocol.
360 * GDB can now step into C++ functions which are called through thunks.
362 * GDB for the Cell/B.E. SPU now supports overlay debugging.
364 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
365 layout. It also supports a TextSeg= and DataSeg= response when only
366 segment base addresses (rather than offsets) are available.
368 * The /i format now outputs any trailing branch delay slot instructions
369 immediately following the last instruction within the count specified.
371 * The GDB remote protocol "T" stop reply packet now supports a
372 "library" response. Combined with the new "qXfer:libraries:read"
373 packet, this response allows GDB to debug shared libraries on targets
374 where the operating system manages the list of loaded libraries (e.g.
375 Windows and SymbianOS).
377 * The GDB remote stub, gdbserver, now supports dynamic link libraries
378 (DLLs) on Windows and Windows CE targets.
380 * GDB now supports a faster verification that a .debug file matches its binary
381 according to its build-id signature, if the signature is present.
387 Enable or disable hardware flow control (RTS/CTS) on the serial port
388 when debugging using remote targets.
390 set mem inaccessible-by-default
391 show mem inaccessible-by-default
392 If the target supplies a memory map, for instance via the remote
393 protocol's "qXfer:memory-map:read" packet, setting this variable
394 prevents GDB from accessing memory outside the memory map. This
395 is useful for targets with memory mapped registers or which react
396 badly to accesses of unmapped address space.
398 set breakpoint auto-hw
399 show breakpoint auto-hw
400 If the target supplies a memory map, for instance via the remote
401 protocol's "qXfer:memory-map:read" packet, setting this variable
402 lets GDB use hardware breakpoints automatically for memory regions
403 where it can not use software breakpoints. This covers both the
404 "break" command and internal breakpoints used for other commands
405 including "next" and "finish".
408 catch exception unhandled
409 Stop the program execution when Ada exceptions are raised.
412 Stop the program execution when an Ada assertion failed.
416 Set an alternate system root for target files. This is a more
417 general version of "set solib-absolute-prefix", which is now
418 an alias to "set sysroot".
421 Provide extended SPU facility status information. This set of
422 commands is available only when debugging the Cell/B.E. SPU
425 * New native configurations
427 OpenBSD/sh sh*-*openbsd*
432 Use the specified local file as an XML target description, and do
433 not query the target for its built-in description.
437 OpenBSD/sh sh*-*-openbsd*
438 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
439 Toshiba Media Processor mep-elf
444 Ignore the specified signals; pass them directly to the debugged program
445 without stopping other threads or reporting them to GDB.
448 Read an XML target description from the target, which describes its
453 Read or write contents of an spufs file on the target system. These
454 packets are available only on the Cell/B.E. SPU architecture.
456 qXfer:libraries:read:
457 Report the loaded shared libraries. Combined with new "T" packet
458 response, this packet allows GDB to debug shared libraries on
459 targets where the operating system manages the list of loaded
460 libraries (e.g. Windows and SymbianOS).
464 Support for these obsolete configurations has been removed.
473 i[34567]86-*-netware*
474 i[34567]86-*-sco3.2v5*
475 i[34567]86-*-sco3.2v4*
477 i[34567]86-*-sysv4.2*
480 i[34567]86-*-unixware2*
481 i[34567]86-*-unixware*
490 * Other removed features
497 Various m68k-only ROM monitors.
504 Various Renesas ROM monitors and debugging interfaces for SH and
509 Support for a Macraigor serial interface to on-chip debugging.
510 GDB does not directly support the newer parallel or USB
515 A debug information format. The predecessor to DWARF 2 and
516 DWARF 3, which are still supported.
518 Support for the HP aCC compiler on HP-UX/PA-RISC
520 SOM-encapsulated symbolic debugging information, automatic
521 invocation of pxdb, and the aCC custom C++ ABI. This does not
522 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
523 with aCC can still be debugged on an assembly level.
527 A MIPS-specific format used to describe stack frame layout
528 in debugging information.
532 GDB could work with an older version of Guile to debug
533 the interpreter and Scheme programs running in it.
535 set mips stack-arg-size
536 set mips saved-gpreg-size
538 Use "set mips abi" to control parameter passing for MIPS.
540 *** Changes in GDB 6.6
545 Cell Broadband Engine SPU spu-elf
547 * GDB can now be configured as a cross-debugger targeting native Windows
548 (mingw32) or Cygwin. It can communicate with a remote debugging stub
549 running on a Windows system over TCP/IP to debug Windows programs.
551 * The GDB remote stub, gdbserver, has been updated to support Windows and
552 Cygwin debugging. Both single-threaded and multi-threaded programs are
555 * The "set trust-readonly-sections" command works again. This command was
556 broken in GDB 6.3, 6.4, and 6.5.
558 * The "load" command now supports writing to flash memory, if the remote
559 stub provides the required support.
561 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
562 longer requires symbolic debug information (e.g. DWARF-2).
567 unset substitute-path
569 Manage a list of substitution rules that GDB uses to rewrite the name
570 of the directories where the sources are located. This can be useful
571 for instance when the sources were moved to a different location
572 between compilation and debugging.
576 Print each CLI command as it is executed. Each command is prefixed with
577 a number of `+' symbols representing the nesting depth.
578 The source command now has a `-v' option to enable the same feature.
582 The ARM Demon monitor support (RDP protocol, "target rdp").
584 Kernel Object Display, an embedded debugging feature which only worked with
585 an obsolete version of Cisco IOS.
587 The 'set download-write-size' and 'show download-write-size' commands.
592 Tell a stub about GDB client features, and request remote target features.
593 The first feature implemented is PacketSize, which allows the target to
594 specify the size of packets it can handle - to minimize the number of
595 packets required and improve performance when connected to a remote
599 Fetch an OS auxilliary vector from the remote stub. This packet is a
600 more efficient replacement for qPart:auxv:read.
602 qXfer:memory-map:read:
603 Fetch a memory map from the remote stub, including information about
604 RAM, ROM, and flash memory devices.
609 Erase and program a flash memory device.
611 * Removed remote packets
614 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
615 used it, and only gdbserver implemented it.
617 *** Changes in GDB 6.5
621 Renesas M32C/M16C m32c-elf
623 Morpho Technologies ms1 ms1-elf
627 init-if-undefined Initialize a convenience variable, but
628 only if it doesn't already have a value.
630 The following commands are presently only implemented for native GNU/Linux:
632 checkpoint Save a snapshot of the program state.
634 restart <n> Return the program state to a
635 previously saved state.
637 info checkpoints List currently saved checkpoints.
639 delete-checkpoint <n> Delete a previously saved checkpoint.
641 set|show detach-on-fork Tell gdb whether to detach from a newly
642 forked process, or to keep debugging it.
644 info forks List forks of the user program that
645 are available to be debugged.
647 fork <n> Switch to debugging one of several
648 forks of the user program that are
649 available to be debugged.
651 delete-fork <n> Delete a fork from the list of forks
652 that are available to be debugged (and
653 kill the forked process).
655 detach-fork <n> Delete a fork from the list of forks
656 that are available to be debugged (and
657 allow the process to continue).
661 Morpho Technologies ms2 ms1-elf
663 * Improved Windows host support
665 GDB now builds as a cross debugger hosted on i686-mingw32, including
666 native console support, and remote communications using either
667 network sockets or serial ports.
669 * Improved Modula-2 language support
671 GDB can now print most types in the Modula-2 syntax. This includes:
672 basic types, set types, record types, enumerated types, range types,
673 pointer types and ARRAY types. Procedure var parameters are correctly
674 printed and hexadecimal addresses and character constants are also
675 written in the Modula-2 syntax. Best results can be obtained by using
676 GNU Modula-2 together with the -gdwarf-2 command line option.
680 The ARM rdi-share module.
682 The Netware NLM debug server.
684 *** Changes in GDB 6.4
686 * New native configurations
688 OpenBSD/arm arm*-*-openbsd*
689 OpenBSD/mips64 mips64-*-openbsd*
693 Morpho Technologies ms1 ms1-elf
695 * New command line options
697 --batch-silent As for --batch, but totally silent.
698 --return-child-result The debugger will exist with the same value
699 the child (debugged) program exited with.
700 --eval-command COMMAND, -ex COMMAND
701 Execute a single GDB CLI command. This may be
702 specified multiple times and in conjunction
703 with the --command (-x) option.
705 * Deprecated commands removed
707 The following commands, that were deprecated in 2000, have been
711 set|show arm disassembly-flavor set|show arm disassembler
712 othernames set arm disassembler
713 set|show remotedebug set|show debug remote
714 set|show archdebug set|show debug arch
715 set|show eventdebug set|show debug event
718 * New BSD user-level threads support
720 It is now possible to debug programs using the user-level threads
721 library on OpenBSD and FreeBSD. Currently supported (target)
724 FreeBSD/amd64 x86_64-*-freebsd*
725 FreeBSD/i386 i386-*-freebsd*
726 OpenBSD/i386 i386-*-openbsd*
728 Note that the new kernel threads libraries introduced in FreeBSD 5.x
729 are not yet supported.
731 * New support for Matsushita MN10300 w/sim added
732 (Work in progress). mn10300-elf.
734 * REMOVED configurations and files
736 VxWorks and the XDR protocol *-*-vxworks
737 Motorola MCORE mcore-*-*
738 National Semiconductor NS32000 ns32k-*-*
740 * New "set print array-indexes" command
742 After turning this setting "on", GDB prints the index of each element
743 when displaying arrays. The default is "off" to preserve the previous
746 * VAX floating point support
748 GDB now supports the not-quite-ieee VAX F and D floating point formats.
750 * User-defined command support
752 In addition to using $arg0..$arg9 for argument passing, it is now possible
753 to use $argc to determine now many arguments have been passed. See the
754 section on user-defined commands in the user manual for more information.
756 *** Changes in GDB 6.3:
758 * New command line option
760 GDB now accepts -l followed by a number to set the timeout for remote
763 * GDB works with GCC -feliminate-dwarf2-dups
765 GDB now supports a more compact representation of DWARF-2 debug
766 information using DW_FORM_ref_addr references. These are produced
767 by GCC with the option -feliminate-dwarf2-dups and also by some
768 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
769 to use -feliminate-dwarf2-dups.
771 * Internationalization
773 When supported by the host system, GDB will be built with
774 internationalization (libintl). The task of marking up the sources is
775 continued, we're looking forward to our first translation.
779 Initial support for debugging programs compiled with the GNAT
780 implementation of the Ada programming language has been integrated
781 into GDB. In this release, support is limited to expression evaluation.
783 * New native configurations
785 GNU/Linux/m32r m32r-*-linux-gnu
789 GDB's remote protocol now includes support for the 'p' packet. This
790 packet is used to fetch individual registers from a remote inferior.
792 * END-OF-LIFE registers[] compatibility module
794 GDB's internal register infrastructure has been completely rewritten.
795 The new infrastructure making possible the implementation of key new
796 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
799 GDB 6.3 will be the last release to include the the registers[]
800 compatibility module that allowed out-of-date configurations to
801 continue to work. This change directly impacts the following
813 Unless there is activity to revive these configurations, they will be
814 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
816 * OBSOLETE configurations and files
818 Configurations that have been declared obsolete in this release have
819 been commented out. Unless there is activity to revive these
820 configurations, the next release of GDB will have their sources
830 *** Changes in GDB 6.2.1:
832 * MIPS `break main; run' gave an heuristic-fence-post warning
834 When attempting to run even a simple program, a warning about
835 heuristic-fence-post being hit would be reported. This problem has
838 * MIPS IRIX 'long double' crashed GDB
840 When examining a long double variable, GDB would get a segmentation
841 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
842 IRIX long double values).
846 A bug in the VAX stack code was causing problems with the "next"
847 command. This problem has been fixed.
849 *** Changes in GDB 6.2:
851 * Fix for ``many threads''
853 On GNU/Linux systems that use the NPTL threads library, a program
854 rapidly creating and deleting threads would confuse GDB leading to the
857 ptrace: No such process.
858 thread_db_get_info: cannot get thread info: generic error
860 This problem has been fixed.
862 * "-async" and "-noasync" options removed.
864 Support for the broken "-noasync" option has been removed (it caused
867 * New ``start'' command.
869 This command runs the program until the begining of the main procedure.
871 * New BSD Kernel Data Access Library (libkvm) interface
873 Using ``target kvm'' it is now possible to debug kernel core dumps and
874 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
875 platforms. Currently supported (native-only) configurations are:
877 FreeBSD/amd64 x86_64-*-freebsd*
878 FreeBSD/i386 i?86-*-freebsd*
879 NetBSD/i386 i?86-*-netbsd*
880 NetBSD/m68k m68*-*-netbsd*
881 NetBSD/sparc sparc-*-netbsd*
882 OpenBSD/amd64 x86_64-*-openbsd*
883 OpenBSD/i386 i?86-*-openbsd*
884 OpenBSD/m68k m68*-openbsd*
885 OpenBSD/sparc sparc-*-openbsd*
887 * Signal trampoline code overhauled
889 Many generic problems with GDB's signal handling code have been fixed.
890 These include: backtraces through non-contiguous stacks; recognition
891 of sa_sigaction signal trampolines; backtrace from a NULL pointer
892 call; backtrace through a signal trampoline; step into and out of
893 signal handlers; and single-stepping in the signal trampoline.
895 Please note that kernel bugs are a limiting factor here. These
896 features have been shown to work on an s390 GNU/Linux system that
897 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
899 * Cygwin support for DWARF 2 added.
901 * New native configurations
903 GNU/Linux/hppa hppa*-*-linux*
904 OpenBSD/hppa hppa*-*-openbsd*
905 OpenBSD/m68k m68*-*-openbsd*
906 OpenBSD/m88k m88*-*-openbsd*
907 OpenBSD/powerpc powerpc-*-openbsd*
908 NetBSD/vax vax-*-netbsd*
909 OpenBSD/vax vax-*-openbsd*
911 * END-OF-LIFE frame compatibility module
913 GDB's internal frame infrastructure has been completely rewritten.
914 The new infrastructure making it possible to support key new features
915 including DWARF 2 Call Frame Information. To aid in the task of
916 migrating old configurations to this new infrastructure, a
917 compatibility module, that allowed old configurations to continue to
918 work, was also included.
920 GDB 6.2 will be the last release to include this frame compatibility
921 module. This change directly impacts the following configurations:
931 Unless there is activity to revive these configurations, they will be
932 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
934 * REMOVED configurations and files
936 Sun 3, running SunOS 3 m68*-*-sunos3*
937 Sun 3, running SunOS 4 m68*-*-sunos4*
938 Sun 2, running SunOS 3 m68000-*-sunos3*
939 Sun 2, running SunOS 4 m68000-*-sunos4*
940 Motorola 680x0 running LynxOS m68*-*-lynxos*
941 AT&T 3b1/Unix pc m68*-att-*
942 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
943 decstation mips-dec-* mips-little-*
944 riscos mips-*-riscos* mips-*-sysv*
946 sysv mips*-*-sysv4* (IRIX 5/6 not included)
948 *** Changes in GDB 6.1.1:
950 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
952 The TUI (Text-mode User Interface) is now built as part of a default
953 GDB configuration. It is enabled by either selecting the TUI with the
954 command line option "-i=tui" or by running the separate "gdbtui"
955 program. For more information on the TUI, see the manual "Debugging
958 * Pending breakpoint support (also included in GDB 6.1)
960 Support has been added to allow you to specify breakpoints in shared
961 libraries that have not yet been loaded. If a breakpoint location
962 cannot be found, and the "breakpoint pending" option is set to auto,
963 GDB queries you if you wish to make the breakpoint pending on a future
964 shared-library load. If and when GDB resolves the breakpoint symbol,
965 the pending breakpoint is removed as one or more regular breakpoints
968 Pending breakpoints are very useful for GCJ Java debugging.
970 * Fixed ISO-C build problems
972 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
973 non ISO-C code that stopped them being built using a more strict ISO-C
974 compiler (e.g., IBM's C compiler).
976 * Fixed build problem on IRIX 5
978 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
979 wasn't able to compile compile on an IRIX 5 system.
981 * Added execute permission to gdb/gdbserver/configure
983 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
984 permission. This bug would cause configure to fail on a number of
985 systems (Solaris, IRIX). Ref: server/519.
987 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
989 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
990 has been updated to use constant array sizes.
992 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
994 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
995 its generated DWARF Call Frame Info. This encoding was causing GDB to
996 panic, that panic has been fixed. Ref: gdb/1628.
998 * Fixed a problem when examining parameters in shared library code.
1000 When examining parameters in optimized shared library code generated
1001 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
1002 not available''. GDB now correctly displays the variable's value.
1004 *** Changes in GDB 6.1:
1006 * Removed --with-mmalloc
1008 Support for the mmalloc memory manager has been removed, as it
1009 conflicted with the internal gdb byte cache.
1011 * Changes in AMD64 configurations
1013 The AMD64 target now includes the %cs and %ss registers. As a result
1014 the AMD64 remote protocol has changed; this affects the floating-point
1015 and SSE registers. If you rely on those registers for your debugging,
1016 you should upgrade gdbserver on the remote side.
1018 * Revised SPARC target
1020 The SPARC target has been completely revised, incorporating the
1021 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
1022 support for LynxOS and SunOS 4 has been dropped. Calling functions
1023 from within GDB on operating systems with a non-executable stack
1024 (Solaris, OpenBSD) now works.
1028 GDB has a new C++ demangler which does a better job on the mangled
1029 names generated by current versions of g++. It also runs faster, so
1030 with this and other changes gdb should now start faster on large C++
1033 * DWARF 2 Location Expressions
1035 GDB support for location expressions has been extended to support function
1036 arguments and frame bases. Older versions of GDB could crash when they
1039 * C++ nested types and namespaces
1041 GDB's support for nested types and namespaces in C++ has been
1042 improved, especially if you use the DWARF 2 debugging format. (This
1043 is the default for recent versions of GCC on most platforms.)
1044 Specifically, if you have a class "Inner" defined within a class or
1045 namespace "Outer", then GDB realizes that the class's name is
1046 "Outer::Inner", not simply "Inner". This should greatly reduce the
1047 frequency of complaints about not finding RTTI symbols. In addition,
1048 if you are stopped at inside of a function defined within a namespace,
1049 GDB modifies its name lookup accordingly.
1051 * New native configurations
1053 NetBSD/amd64 x86_64-*-netbsd*
1054 OpenBSD/amd64 x86_64-*-openbsd*
1055 OpenBSD/alpha alpha*-*-openbsd*
1056 OpenBSD/sparc sparc-*-openbsd*
1057 OpenBSD/sparc64 sparc64-*-openbsd*
1059 * New debugging protocols
1061 M32R with SDI protocol m32r-*-elf*
1063 * "set prompt-escape-char" command deleted.
1065 The command "set prompt-escape-char" has been deleted. This command,
1066 and its very obscure effet on GDB's prompt, was never documented,
1067 tested, nor mentioned in the NEWS file.
1069 * OBSOLETE configurations and files
1071 Configurations that have been declared obsolete in this release have
1072 been commented out. Unless there is activity to revive these
1073 configurations, the next release of GDB will have their sources
1074 permanently REMOVED.
1076 Sun 3, running SunOS 3 m68*-*-sunos3*
1077 Sun 3, running SunOS 4 m68*-*-sunos4*
1078 Sun 2, running SunOS 3 m68000-*-sunos3*
1079 Sun 2, running SunOS 4 m68000-*-sunos4*
1080 Motorola 680x0 running LynxOS m68*-*-lynxos*
1081 AT&T 3b1/Unix pc m68*-att-*
1082 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
1083 decstation mips-dec-* mips-little-*
1084 riscos mips-*-riscos* mips-*-sysv*
1085 sonymips mips-sony-*
1086 sysv mips*-*-sysv4* (IRIX 5/6 not included)
1088 * REMOVED configurations and files
1090 SGI Irix-4.x mips-sgi-irix4 or iris4
1091 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1092 Z8000 simulator z8k-zilog-none or z8ksim
1093 Matsushita MN10200 w/simulator mn10200-*-*
1094 H8/500 simulator h8500-hitachi-hms or h8500hms
1095 HP/PA running BSD hppa*-*-bsd*
1096 HP/PA running OSF/1 hppa*-*-osf*
1097 HP/PA Pro target hppa*-*-pro*
1098 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1099 386BSD i[3456]86-*-bsd*
1100 Sequent family i[3456]86-sequent-sysv4*
1101 i[3456]86-sequent-sysv*
1102 i[3456]86-sequent-bsd*
1103 SPARC running LynxOS sparc-*-lynxos*
1104 SPARC running SunOS 4 sparc-*-sunos4*
1105 Tsqware Sparclet sparclet-*-*
1106 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1108 *** Changes in GDB 6.0:
1112 Support for debugging the Objective-C programming language has been
1113 integrated into GDB.
1115 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
1117 DWARF 2's Call Frame Information makes available compiler generated
1118 information that more exactly describes the program's run-time stack.
1119 By using this information, GDB is able to provide more robust stack
1122 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
1123 have been updated to use a new backtrace mechanism which includes
1124 DWARF 2 CFI support.
1128 GDB's remote protocol has been extended to include support for hosted
1129 file I/O (where the remote target uses GDB's file system). See GDB's
1130 remote protocol documentation for details.
1132 * All targets using the new architecture framework.
1134 All of GDB's targets have been updated to use the new internal
1135 architecture framework. The way is now open for future GDB releases
1136 to include cross-architecture native debugging support (i386 on amd64,
1139 * GNU/Linux's Thread Local Storage (TLS)
1141 GDB now includes support for for the GNU/Linux implementation of
1142 per-thread variables.
1144 * GNU/Linux's Native POSIX Thread Library (NPTL)
1146 GDB's thread code has been updated to work with either the new
1147 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
1149 * Separate debug info.
1151 GDB, in conjunction with BINUTILS, now supports a mechanism for
1152 automatically loading debug information from a separate file. Instead
1153 of shipping full debug and non-debug versions of system libraries,
1154 system integrators can now instead ship just the stripped libraries
1155 and optional debug files.
1157 * DWARF 2 Location Expressions
1159 DWARF 2 Location Expressions allow the compiler to more completely
1160 describe the location of variables (even in optimized code) to the
1163 GDB now includes preliminary support for location expressions (support
1164 for DW_OP_piece is still missing).
1168 A number of long standing bugs that caused GDB to die while starting a
1169 Java application have been fixed. GDB's Java support is now
1170 considered "useable".
1172 * GNU/Linux support for fork, vfork, and exec.
1174 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1175 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1178 * GDB supports logging output to a file
1180 There are two new commands, "set logging" and "show logging", which can be
1181 used to capture GDB's output to a file.
1183 * The meaning of "detach" has changed for gdbserver
1185 The "detach" command will now resume the application, as documented. To
1186 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1189 * d10v, m68hc11 `regs' command deprecated
1191 The `info registers' command has been updated so that it displays the
1192 registers using a format identical to the old `regs' command.
1196 A new command, "maint set profile on/off", has been added. This command can
1197 be used to enable or disable profiling while running GDB, to profile a
1198 session or a set of commands. In addition there is a new configure switch,
1199 "--enable-profiling", which will cause GDB to be compiled with profiling
1200 data, for more informative profiling results.
1202 * Default MI syntax changed to "mi2".
1204 The default MI (machine interface) syntax, enabled by the command line
1205 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1206 "mi1", can be enabled by specifying the option "-i=mi1".
1208 Support for the original "mi0" syntax (included in GDB 5.0) has been
1211 Fix for gdb/192: removed extraneous space when displaying frame level.
1212 Fix for gdb/672: update changelist is now output in mi list format.
1213 Fix for gdb/702: a -var-assign that updates the value now shows up
1214 in a subsequent -var-update.
1216 * New native configurations.
1218 FreeBSD/amd64 x86_64-*-freebsd*
1220 * Multi-arched targets.
1222 HP/PA HPUX11 hppa*-*-hpux*
1223 Renesas M32R/D w/simulator m32r-*-elf*
1225 * OBSOLETE configurations and files
1227 Configurations that have been declared obsolete in this release have
1228 been commented out. Unless there is activity to revive these
1229 configurations, the next release of GDB will have their sources
1230 permanently REMOVED.
1232 Z8000 simulator z8k-zilog-none or z8ksim
1233 Matsushita MN10200 w/simulator mn10200-*-*
1234 H8/500 simulator h8500-hitachi-hms or h8500hms
1235 HP/PA running BSD hppa*-*-bsd*
1236 HP/PA running OSF/1 hppa*-*-osf*
1237 HP/PA Pro target hppa*-*-pro*
1238 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1239 Sequent family i[3456]86-sequent-sysv4*
1240 i[3456]86-sequent-sysv*
1241 i[3456]86-sequent-bsd*
1242 Tsqware Sparclet sparclet-*-*
1243 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1245 * REMOVED configurations and files
1248 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1249 IBM AIX PS/2 i[3456]86-*-aix
1250 i386 running Mach 3.0 i[3456]86-*-mach3*
1251 i386 running Mach i[3456]86-*-mach*
1252 i386 running OSF/1 i[3456]86-*osf1mk*
1253 HP/Apollo 68k Family m68*-apollo*-sysv*,
1255 m68*-hp-bsd*, m68*-hp-hpux*
1256 Argonaut Risc Chip (ARC) arc-*-*
1257 Mitsubishi D30V d30v-*-*
1258 Fujitsu FR30 fr30-*-elf*
1259 OS/9000 i[34]86-*-os9k
1260 I960 with MON960 i960-*-coff
1262 * MIPS $fp behavior changed
1264 The convenience variable $fp, for the MIPS, now consistently returns
1265 the address of the current frame's base. Previously, depending on the
1266 context, $fp could refer to either $sp or the current frame's base
1267 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1268 The GNU Source-Level Debugger''.
1270 *** Changes in GDB 5.3:
1272 * GNU/Linux shared library multi-threaded performance improved.
1274 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1275 `/proc', in preference to `ptrace' for memory reads. This may result
1276 in an improvement in the start-up time of multi-threaded, shared
1277 library applications when run under GDB. One GDB user writes: ``loads
1278 shared libs like mad''.
1280 * ``gdbserver'' now supports multi-threaded applications on some targets
1282 Support for debugging multi-threaded applications which use
1283 the GNU/Linux LinuxThreads package has been added for
1284 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1285 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1287 * GDB now supports C/C++ preprocessor macros.
1289 GDB now expands preprocessor macro invocations in C/C++ expressions,
1290 and provides various commands for showing macro definitions and how
1293 The new command `macro expand EXPRESSION' expands any macro
1294 invocations in expression, and shows the result.
1296 The new command `show macro MACRO-NAME' shows the definition of the
1297 macro named MACRO-NAME, and where it was defined.
1299 Most compilers don't include information about macros in the debugging
1300 information by default. In GCC 3.1, for example, you need to compile
1301 your program with the options `-gdwarf-2 -g3'. If the macro
1302 information is present in the executable, GDB will read it.
1304 * Multi-arched targets.
1306 DEC Alpha (partial) alpha*-*-*
1307 DEC VAX (partial) vax-*-*
1309 National Semiconductor NS32000 (partial) ns32k-*-*
1310 Motorola 68000 (partial) m68k-*-*
1311 Motorola MCORE mcore-*-*
1315 Fujitsu FRV architecture added by Red Hat frv*-*-*
1318 * New native configurations
1320 Alpha NetBSD alpha*-*-netbsd*
1321 SH NetBSD sh*-*-netbsdelf*
1322 MIPS NetBSD mips*-*-netbsd*
1323 UltraSPARC NetBSD sparc64-*-netbsd*
1325 * OBSOLETE configurations and files
1327 Configurations that have been declared obsolete in this release have
1328 been commented out. Unless there is activity to revive these
1329 configurations, the next release of GDB will have their sources
1330 permanently REMOVED.
1332 Mitsubishi D30V d30v-*-*
1333 OS/9000 i[34]86-*-os9k
1334 IBM AIX PS/2 i[3456]86-*-aix
1335 Fujitsu FR30 fr30-*-elf*
1336 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1337 Argonaut Risc Chip (ARC) arc-*-*
1338 i386 running Mach 3.0 i[3456]86-*-mach3*
1339 i386 running Mach i[3456]86-*-mach*
1340 i386 running OSF/1 i[3456]86-*osf1mk*
1341 HP/Apollo 68k Family m68*-apollo*-sysv*,
1343 m68*-hp-bsd*, m68*-hp-hpux*
1344 I960 with MON960 i960-*-coff
1346 * OBSOLETE languages
1348 CHILL, a Pascal like language used by telecommunications companies.
1350 * REMOVED configurations and files
1352 AMD 29k family via UDI a29k-amd-udi, udi29k
1353 A29K VxWorks a29k-*-vxworks
1354 AMD 29000 embedded, using EBMON a29k-none-none
1355 AMD 29000 embedded with COFF a29k-none-coff
1356 AMD 29000 embedded with a.out a29k-none-aout
1358 testsuite/gdb.hp/gdb.threads-hp/ directory
1360 * New command "set max-user-call-depth <nnn>"
1362 This command allows the user to limit the call depth of user-defined
1363 commands. The default is 1024.
1365 * Changes in FreeBSD/i386 native debugging.
1367 Support for the "generate-core-file" has been added.
1369 * New commands "dump", "append", and "restore".
1371 These commands allow data to be copied from target memory
1372 to a bfd-format or binary file (dump and append), and back
1373 from a file into memory (restore).
1375 * Improved "next/step" support on multi-processor Alpha Tru64.
1377 The previous single-step mechanism could cause unpredictable problems,
1378 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1379 of a software single-step mechanism prevents this.
1381 *** Changes in GDB 5.2.1:
1389 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1390 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1391 Fix, by Joel Brobecker imported from mainline.
1393 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1394 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1395 Fix, by Fred Fish, imported from mainline.
1397 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1398 Surprisingly enough, it works now.
1399 By Michal Ludvig, imported from mainline.
1401 i386 hardware watchpoint support:
1402 avoid misses on second run for some targets.
1403 By Pierre Muller, imported from mainline.
1405 *** Changes in GDB 5.2:
1407 * New command "set trust-readonly-sections on[off]".
1409 This command is a hint that tells gdb that read-only sections
1410 really are read-only (ie. that their contents will not change).
1411 In this mode, gdb will go to the object file rather than the
1412 target to read memory from read-only sections (such as ".text").
1413 This can be a significant performance improvement on some
1414 (notably embedded) targets.
1416 * New command "generate-core-file" (or "gcore").
1418 This new gdb command allows the user to drop a core file of the child
1419 process state at any time. So far it's been implemented only for
1420 GNU/Linux and Solaris, but should be relatively easily ported to other
1421 hosts. Argument is core file name (defaults to core.<pid>).
1423 * New command line option
1425 GDB now accepts --pid or -p followed by a process id.
1427 * Change in command line behavior -- corefiles vs. process ids.
1429 There is a subtle behavior in the way in which GDB handles
1430 command line arguments. The first non-flag argument is always
1431 a program to debug, but the second non-flag argument may either
1432 be a corefile or a process id. Previously, GDB would attempt to
1433 open the second argument as a corefile, and if that failed, would
1434 issue a superfluous error message and then attempt to attach it as
1435 a process. Now, if the second argument begins with a non-digit,
1436 it will be treated as a corefile. If it begins with a digit,
1437 GDB will attempt to attach it as a process, and if no such process
1438 is found, will then attempt to open it as a corefile.
1440 * Changes in ARM configurations.
1442 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1443 configuration is fully multi-arch.
1445 * New native configurations
1447 ARM NetBSD arm*-*-netbsd*
1448 x86 OpenBSD i[3456]86-*-openbsd*
1449 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1450 Sparc64 running FreeBSD sparc64-*-freebsd*
1454 Sanyo XStormy16 xstormy16-elf
1456 * OBSOLETE configurations and files
1458 Configurations that have been declared obsolete in this release have
1459 been commented out. Unless there is activity to revive these
1460 configurations, the next release of GDB will have their sources
1461 permanently REMOVED.
1463 AMD 29k family via UDI a29k-amd-udi, udi29k
1464 A29K VxWorks a29k-*-vxworks
1465 AMD 29000 embedded, using EBMON a29k-none-none
1466 AMD 29000 embedded with COFF a29k-none-coff
1467 AMD 29000 embedded with a.out a29k-none-aout
1469 testsuite/gdb.hp/gdb.threads-hp/ directory
1471 * REMOVED configurations and files
1473 TI TMS320C80 tic80-*-*
1475 PowerPC Solaris powerpcle-*-solaris*
1476 PowerPC Windows NT powerpcle-*-cygwin32
1477 PowerPC Netware powerpc-*-netware*
1478 Harris/CXUX m88k m88*-harris-cxux*
1479 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1480 ns32k-utek-sysv* ns32k-utek-*
1481 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1482 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1483 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1484 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1485 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1487 * Changes to command line processing
1489 The new `--args' feature can be used to specify command-line arguments
1490 for the inferior from gdb's command line.
1492 * Changes to key bindings
1494 There is a new `operate-and-get-next' function bound to `C-o'.
1496 *** Changes in GDB 5.1.1
1498 Fix compile problem on DJGPP.
1500 Fix a problem with floating-point registers on the i386 being
1503 Fix to stop GDB crashing on .debug_str debug info.
1505 Numerous documentation fixes.
1507 Numerous testsuite fixes.
1509 *** Changes in GDB 5.1:
1511 * New native configurations
1513 Alpha FreeBSD alpha*-*-freebsd*
1514 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1515 MIPS GNU/Linux mips*-*-linux*
1516 MIPS SGI Irix 6.x mips*-sgi-irix6*
1517 ia64 AIX ia64-*-aix*
1518 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1522 Motorola 68HC11 and 68HC12 m68hc11-elf
1524 UltraSparc running GNU/Linux sparc64-*-linux*
1526 * OBSOLETE configurations and files
1528 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1529 Harris/CXUX m88k m88*-harris-cxux*
1530 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1531 ns32k-utek-sysv* ns32k-utek-*
1532 TI TMS320C80 tic80-*-*
1534 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1535 PowerPC Solaris powerpcle-*-solaris*
1536 PowerPC Windows NT powerpcle-*-cygwin32
1537 PowerPC Netware powerpc-*-netware*
1538 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1539 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1540 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1541 Apple Macintosh (MPW) host N/A
1543 stuff.c (Program to stuff files into a specially prepared space in kdb)
1544 kdb-start.c (Main loop for the standalone kernel debugger)
1546 Configurations that have been declared obsolete in this release have
1547 been commented out. Unless there is activity to revive these
1548 configurations, the next release of GDB will have their sources
1549 permanently REMOVED.
1551 * REMOVED configurations and files
1553 Altos 3068 m68*-altos-*
1554 Convex c1-*-*, c2-*-*
1556 ARM RISCix arm-*-* (as host)
1560 * GDB has been converted to ISO C.
1562 GDB's source code has been converted to ISO C. In particular, the
1563 sources are fully protoized, and rely on standard headers being
1568 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1570 * The MI enabled by default.
1572 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1573 revised and enabled by default. Packages which use GDB as a debugging
1574 engine behind a UI or another front end are encouraged to switch to
1575 using the GDB/MI interface, instead of the old annotations interface
1576 which is now deprecated.
1578 * Support for debugging Pascal programs.
1580 GDB now includes support for debugging Pascal programs. The following
1581 main features are supported:
1583 - Pascal-specific data types such as sets;
1585 - automatic recognition of Pascal sources based on file-name
1588 - Pascal-style display of data types, variables, and functions;
1590 - a Pascal expression parser.
1592 However, some important features are not yet supported.
1594 - Pascal string operations are not supported at all;
1596 - there are some problems with boolean types;
1598 - Pascal type hexadecimal constants are not supported
1599 because they conflict with the internal variables format;
1601 - support for Pascal objects and classes is not full yet;
1603 - unlike Pascal, GDB is case-sensitive for symbol names.
1605 * Changes in completion.
1607 Commands such as `shell', `run' and `set args', which pass arguments
1608 to inferior programs, now complete on file names, similar to what
1609 users expect at the shell prompt.
1611 Commands which accept locations, such as `disassemble', `print',
1612 `breakpoint', `until', etc. now complete on filenames as well as
1613 program symbols. Thus, if you type "break foob TAB", and the source
1614 files linked into the programs include `foobar.c', that file name will
1615 be one of the candidates for completion. However, file names are not
1616 considered for completion after you typed a colon that delimits a file
1617 name from a name of a function in that file, as in "break foo.c:bar".
1619 `set demangle-style' completes on available demangling styles.
1621 * New platform-independent commands:
1623 It is now possible to define a post-hook for a command as well as a
1624 hook that runs before the command. For more details, see the
1625 documentation of `hookpost' in the GDB manual.
1627 * Changes in GNU/Linux native debugging.
1629 Support for debugging multi-threaded programs has been completely
1630 revised for all platforms except m68k and sparc. You can now debug as
1631 many threads as your system allows you to have.
1633 Attach/detach is supported for multi-threaded programs.
1635 Support for SSE registers was added for x86. This doesn't work for
1636 multi-threaded programs though.
1638 * Changes in MIPS configurations.
1640 Multi-arch support is enabled for all MIPS configurations.
1642 GDB can now be built as native debugger on SGI Irix 6.x systems for
1643 debugging n32 executables. (Debugging 64-bit executables is not yet
1646 * Unified support for hardware watchpoints in all x86 configurations.
1648 Most (if not all) native x86 configurations support hardware-assisted
1649 breakpoints and watchpoints in a unified manner. This support
1650 implements debug register sharing between watchpoints, which allows to
1651 put a virtually infinite number of watchpoints on the same address,
1652 and also supports watching regions up to 16 bytes with several debug
1655 The new maintenance command `maintenance show-debug-regs' toggles
1656 debugging print-outs in functions that insert, remove, and test
1657 watchpoints and hardware breakpoints.
1659 * Changes in the DJGPP native configuration.
1661 New command ``info dos sysinfo'' displays assorted information about
1662 the CPU, OS, memory, and DPMI server.
1664 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1665 display information about segment descriptors stored in GDT, LDT, and
1668 New commands ``info dos pde'' and ``info dos pte'' display entries
1669 from Page Directory and Page Tables (for now works with CWSDPMI only).
1670 New command ``info dos address-pte'' displays the Page Table entry for
1671 a given linear address.
1673 GDB can now pass command lines longer than 126 characters to the
1674 program being debugged (requires an update to the libdbg.a library
1675 which is part of the DJGPP development kit).
1677 DWARF2 debug info is now supported.
1679 It is now possible to `step' and `next' through calls to `longjmp'.
1681 * Changes in documentation.
1683 All GDB documentation was converted to GFDL, the GNU Free
1684 Documentation License.
1686 Tracepoints-related commands are now fully documented in the GDB
1689 TUI, the Text-mode User Interface, is now documented in the manual.
1691 Tracepoints-related commands are now fully documented in the GDB
1694 The "GDB Internals" manual now has an index. It also includes
1695 documentation of `ui_out' functions, GDB coding standards, x86
1696 hardware watchpoints, and memory region attributes.
1698 * GDB's version number moved to ``version.in''
1700 The Makefile variable VERSION has been replaced by the file
1701 ``version.in''. People creating GDB distributions should update the
1702 contents of this file.
1706 GUD support is now a standard part of the EMACS distribution.
1708 *** Changes in GDB 5.0:
1710 * Improved support for debugging FP programs on x86 targets
1712 Unified and much-improved support for debugging floating-point
1713 programs on all x86 targets. In particular, ``info float'' now
1714 displays the FP registers in the same format on all x86 targets, with
1715 greater level of detail.
1717 * Improvements and bugfixes in hardware-assisted watchpoints
1719 It is now possible to watch array elements, struct members, and
1720 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1721 on x86 targets no longer erroneously trigger when the address is
1724 * Improvements in the native DJGPP version of GDB
1726 The distribution now includes all the scripts and auxiliary files
1727 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1728 machines ``out of the box''.
1730 The DJGPP version can now debug programs that use signals. It is
1731 possible to catch signals that happened in the debuggee, deliver
1732 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1733 would kill the program being debugged.) Programs that hook hardware
1734 interrupts (keyboard, timer, etc.) can also be debugged.
1736 It is now possible to debug DJGPP programs that redirect their
1737 standard handles or switch them to raw (as opposed to cooked) mode, or
1738 even close them. The command ``run < foo > bar'' works as expected,
1739 and ``info terminal'' reports useful information about the debuggee's
1740 terminal, including raw/cooked mode, redirection, etc.
1742 The DJGPP version now uses termios functions for console I/O, which
1743 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1746 DOS-style file names with drive letters are now fully supported by
1749 It is now possible to debug DJGPP programs that switch their working
1750 directory. It is also possible to rerun the debuggee any number of
1751 times without restarting GDB; thus, you can use the same setup,
1752 breakpoints, etc. for many debugging sessions.
1754 * New native configurations
1756 ARM GNU/Linux arm*-*-linux*
1757 PowerPC GNU/Linux powerpc-*-linux*
1761 Motorola MCore mcore-*-*
1762 x86 VxWorks i[3456]86-*-vxworks*
1763 PowerPC VxWorks powerpc-*-vxworks*
1764 TI TMS320C80 tic80-*-*
1766 * OBSOLETE configurations
1768 Altos 3068 m68*-altos-*
1769 Convex c1-*-*, c2-*-*
1771 ARM RISCix arm-*-* (as host)
1774 Configurations that have been declared obsolete will be commented out,
1775 but the code will be left in place. If there is no activity to revive
1776 these configurations before the next release of GDB, the sources will
1777 be permanently REMOVED.
1779 * Gould support removed
1781 Support for the Gould PowerNode and NP1 has been removed.
1783 * New features for SVR4
1785 On SVR4 native platforms (such as Solaris), if you attach to a process
1786 without first loading a symbol file, GDB will now attempt to locate and
1787 load symbols from the running process's executable file.
1789 * Many C++ enhancements
1791 C++ support has been greatly improved. Overload resolution now works properly
1792 in almost all cases. RTTI support is on the way.
1794 * Remote targets can connect to a sub-program
1796 A popen(3) style serial-device has been added. This device starts a
1797 sub-process (such as a stand-alone simulator) and then communicates
1798 with that. The sub-program to run is specified using the syntax
1799 ``|<program> <args>'' vis:
1801 (gdb) set remotedebug 1
1802 (gdb) target extended-remote |mn10300-elf-sim program-args
1804 * MIPS 64 remote protocol
1806 A long standing bug in the mips64 remote protocol where by GDB
1807 expected certain 32 bit registers (ex SR) to be transfered as 32
1808 instead of 64 bits has been fixed.
1810 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1811 added to provide backward compatibility with older versions of GDB.
1813 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1815 The command ``set remotebinarydownload'' command has been replaced by
1816 ``set remote X-packet''. Other commands in ``set remote'' family
1817 include ``set remote P-packet''.
1819 * Breakpoint commands accept ranges.
1821 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1822 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1823 ``tracepoint passcount'' also accepts a range of tracepoints.
1825 * ``apropos'' command added.
1827 The ``apropos'' command searches through command names and
1828 documentation strings, printing out matches, making it much easier to
1829 try to find a command that does what you are looking for.
1833 A new machine oriented interface (MI) has been added to GDB. This
1834 interface is designed for debug environments running GDB as a separate
1835 process. This is part of the long term libGDB project. See the
1836 "GDB/MI" chapter of the GDB manual for further information. It can be
1837 enabled by configuring with:
1839 .../configure --enable-gdbmi
1841 *** Changes in GDB-4.18:
1843 * New native configurations
1845 HP-UX 10.20 hppa*-*-hpux10.20
1846 HP-UX 11.x hppa*-*-hpux11.0*
1847 M68K GNU/Linux m68*-*-linux*
1851 Fujitsu FR30 fr30-*-elf*
1852 Intel StrongARM strongarm-*-*
1853 Mitsubishi D30V d30v-*-*
1855 * OBSOLETE configurations
1857 Gould PowerNode, NP1 np1-*-*, pn-*-*
1859 Configurations that have been declared obsolete will be commented out,
1860 but the code will be left in place. If there is no activity to revive
1861 these configurations before the next release of GDB, the sources will
1862 be permanently REMOVED.
1866 As a compatibility experiment, GDB's source files buildsym.h and
1867 buildsym.c have been converted to pure standard C, no longer
1868 containing any K&R compatibility code. We believe that all systems in
1869 use today either come with a standard C compiler, or have a GCC port
1870 available. If this is not true, please report the affected
1871 configuration to bug-gdb@gnu.org immediately. See the README file for
1872 information about getting a standard C compiler if you don't have one
1877 GDB now uses readline 2.2.
1879 * set extension-language
1881 You can now control the mapping between filename extensions and source
1882 languages by using the `set extension-language' command. For instance,
1883 you can ask GDB to treat .c files as C++ by saying
1884 set extension-language .c c++
1885 The command `info extensions' lists all of the recognized extensions
1886 and their associated languages.
1888 * Setting processor type for PowerPC and RS/6000
1890 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1891 you can use the `set processor' command to specify what variant of the
1892 PowerPC family you are debugging. The command
1896 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
1897 following PowerPC and RS6000 variants:
1899 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
1900 rs6000 IBM RS6000 ("POWER") architecture, user-level view
1902 403GC IBM PowerPC 403GC
1903 505 Motorola PowerPC 505
1904 860 Motorola PowerPC 860 or 850
1905 601 Motorola PowerPC 601
1906 602 Motorola PowerPC 602
1907 603 Motorola/IBM PowerPC 603 or 603e
1908 604 Motorola PowerPC 604 or 604e
1909 750 Motorola/IBM PowerPC 750 or 750
1911 At the moment, this command just tells GDB what to name the
1912 special-purpose processor registers. Since almost all the affected
1913 registers are inaccessible to user-level programs, this command is
1914 only useful for remote debugging in its present form.
1918 Thanks to a major code donation from Hewlett-Packard, GDB now has much
1919 more extensive support for HP-UX. Added features include shared
1920 library support, kernel threads and hardware watchpoints for 11.00,
1921 support for HP's ANSI C and C++ compilers, and a compatibility mode
1922 for xdb and dbx commands.
1926 HP's donation includes the new concept of catchpoints, which is a
1927 generalization of the old catch command. On HP-UX, it is now possible
1928 to catch exec, fork, and vfork, as well as library loading.
1930 This means that the existing catch command has changed; its first
1931 argument now specifies the type of catch to be set up. See the
1932 output of "help catch" for a list of catchpoint types.
1934 * Debugging across forks
1936 On HP-UX, you can choose which process to debug when a fork() happens
1941 HP has donated a curses-based terminal user interface (TUI). To get
1942 it, build with --enable-tui. Although this can be enabled for any
1943 configuration, at present it only works for native HP debugging.
1945 * GDB remote protocol additions
1947 A new protocol packet 'X' that writes binary data is now available.
1948 Default behavior is to try 'X', then drop back to 'M' if the stub
1949 fails to respond. The settable variable `remotebinarydownload'
1950 allows explicit control over the use of 'X'.
1952 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1953 full 64-bit address. The command
1955 set remoteaddresssize 32
1957 can be used to revert to the old behaviour. For existing remote stubs
1958 the change should not be noticed, as the additional address information
1961 In order to assist in debugging stubs, you may use the maintenance
1962 command `packet' to send any text string to the stub. For instance,
1964 maint packet heythere
1966 sends the packet "$heythere#<checksum>". Note that it is very easy to
1967 disrupt a debugging session by sending the wrong packet at the wrong
1970 The compare-sections command allows you to compare section data on the
1971 target to what is in the executable file without uploading or
1972 downloading, by comparing CRC checksums.
1974 * Tracing can collect general expressions
1976 You may now collect general expressions at tracepoints. This requires
1977 further additions to the target-side stub; see tracepoint.c and
1978 doc/agentexpr.texi for further details.
1980 * mask-address variable for Mips
1982 For Mips targets, you may control the zeroing of the upper 32 bits of
1983 a 64-bit address by entering `set mask-address on'. This is mainly
1984 of interest to users of embedded R4xxx and R5xxx processors.
1986 * Higher serial baud rates
1988 GDB's serial code now allows you to specify baud rates 57600, 115200,
1989 230400, and 460800 baud. (Note that your host system may not be able
1990 to achieve all of these rates.)
1994 The i960 configuration now includes an initial implementation of a
1995 builtin simulator, contributed by Jim Wilson.
1998 *** Changes in GDB-4.17:
2000 * New native configurations
2002 Alpha GNU/Linux alpha*-*-linux*
2003 Unixware 2.x i[3456]86-unixware2*
2004 Irix 6.x mips*-sgi-irix6*
2005 PowerPC GNU/Linux powerpc-*-linux*
2006 PowerPC Solaris powerpcle-*-solaris*
2007 Sparc GNU/Linux sparc-*-linux*
2008 Motorola sysV68 R3V7.1 m68k-motorola-sysv
2012 Argonaut Risc Chip (ARC) arc-*-*
2013 Hitachi H8/300S h8300*-*-*
2014 Matsushita MN10200 w/simulator mn10200-*-*
2015 Matsushita MN10300 w/simulator mn10300-*-*
2016 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
2017 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
2018 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
2019 Mitsubishi D10V w/simulator d10v-*-*
2020 Mitsubishi M32R/D w/simulator m32r-*-elf*
2021 Tsqware Sparclet sparclet-*-*
2022 NEC V850 w/simulator v850-*-*
2024 * New debugging protocols
2026 ARM with RDI protocol arm*-*-*
2027 M68K with dBUG monitor m68*-*-{aout,coff,elf}
2028 DDB and LSI variants of PMON protocol mips*-*-*
2029 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
2030 PowerPC with SDS protocol powerpc{,le}-*-eabi
2031 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
2035 All configurations can now understand and use the DWARF 2 debugging
2036 format. The choice is automatic, if the symbol file contains DWARF 2
2041 GDB now includes basic Java language support. This support is
2042 only useful with Java compilers that produce native machine code.
2044 * solib-absolute-prefix and solib-search-path
2046 For SunOS and SVR4 shared libraries, you may now set the prefix for
2047 loading absolute shared library symbol files, and the search path for
2048 locating non-absolute shared library symbol files.
2050 * Live range splitting
2052 GDB can now effectively debug code for which GCC has performed live
2053 range splitting as part of its optimization. See gdb/doc/LRS for
2054 more details on the expected format of the stabs information.
2058 GDB's support for the GNU Hurd, including thread debugging, has been
2059 updated to work with current versions of the Hurd.
2063 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
2064 instruction set. ARM GDB automatically detects when Thumb
2065 instructions are in use, and adjusts disassembly and backtracing
2070 GDB's MIPS target configurations now handle the MIP16 16-bit
2075 GDB now includes support for overlays; if an executable has been
2076 linked such that multiple sections are based at the same address, GDB
2077 will decide which section to use for symbolic info. You can choose to
2078 control the decision manually, using overlay commands, or implement
2079 additional target-side support and use "overlay load-target" to bring
2080 in the overlay mapping. Do "help overlay" for more detail.
2084 The command "info symbol <address>" displays information about
2085 the symbol at the specified address.
2089 The standard remote protocol now includes an extension that allows
2090 asynchronous collection and display of trace data. This requires
2091 extensive support in the target-side debugging stub. Tracing mode
2092 includes a new interaction mode in GDB and new commands: see the
2093 file tracepoint.c for more details.
2097 Configurations for embedded MIPS now include a simulator contributed
2098 by Cygnus Solutions. The simulator supports the instruction sets
2099 of most MIPS variants.
2103 Sparc configurations may now include the ERC32 simulator contributed
2104 by the European Space Agency. The simulator is not built into
2105 Sparc targets by default; configure with --enable-sim to include it.
2109 For target configurations that may include multiple variants of a
2110 basic architecture (such as MIPS and SH), you may now set the
2111 architecture explicitly. "set arch" sets, "info arch" lists
2112 the possible architectures.
2114 *** Changes in GDB-4.16:
2116 * New native configurations
2118 Windows 95, x86 Windows NT i[345]86-*-cygwin32
2119 M68K NetBSD m68k-*-netbsd*
2120 PowerPC AIX 4.x powerpc-*-aix*
2121 PowerPC MacOS powerpc-*-macos*
2122 PowerPC Windows NT powerpcle-*-cygwin32
2123 RS/6000 AIX 4.x rs6000-*-aix4*
2127 ARM with RDP protocol arm-*-*
2128 I960 with MON960 i960-*-coff
2129 MIPS VxWorks mips*-*-vxworks*
2130 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
2131 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
2133 Matra Sparclet sparclet-*-*
2137 The powerpc-eabi configuration now includes the PSIM simulator,
2138 contributed by Andrew Cagney, with assistance from Mike Meissner.
2139 PSIM is a very elaborate model of the PowerPC, including not only
2140 basic instruction set execution, but also details of execution unit
2141 performance and I/O hardware. See sim/ppc/README for more details.
2145 GDB now works with Solaris 2.5.
2147 * Windows 95/NT native
2149 GDB will now work as a native debugger on Windows 95 and Windows NT.
2150 To build it from source, you must use the "gnu-win32" environment,
2151 which uses a DLL to emulate enough of Unix to run the GNU tools.
2152 Further information, binaries, and sources are available at
2153 ftp.cygnus.com, under pub/gnu-win32.
2155 * dont-repeat command
2157 If a user-defined command includes the command `dont-repeat', then the
2158 command will not be repeated if the user just types return. This is
2159 useful if the command is time-consuming to run, so that accidental
2160 extra keystrokes don't run the same command many times.
2162 * Send break instead of ^C
2164 The standard remote protocol now includes an option to send a break
2165 rather than a ^C to the target in order to interrupt it. By default,
2166 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2168 * Remote protocol timeout
2170 The standard remote protocol includes a new variable `remotetimeout'
2171 that allows you to set the number of seconds before GDB gives up trying
2172 to read from the target. The default value is 2.
2174 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2176 By default GDB will automatically keep track of objects as they are
2177 loaded and unloaded by the dynamic linker. By using the command `set
2178 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2179 when shared library events occur, thus allowing you to set breakpoints
2180 in shared libraries which are explicitly loaded by the inferior.
2182 Note this feature does not work on hpux8. On hpux9 you must link
2183 /usr/lib/end.o into your program. This feature should work
2184 automatically on hpux10.
2186 * Irix 5.x hardware watchpoint support
2188 Irix 5 configurations now support the use of hardware watchpoints.
2190 * Mips protocol "SYN garbage limit"
2192 When debugging a Mips target using the `target mips' protocol, you
2193 may set the number of characters that GDB will ignore by setting
2194 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2195 every character. The default value is 1050.
2197 * Recording and replaying remote debug sessions
2199 If you set `remotelogfile' to the name of a file, gdb will write to it
2200 a recording of a remote debug session. This recording may then be
2201 replayed back to gdb using "gdbreplay". See gdbserver/README for
2202 details. This is useful when you have a problem with GDB while doing
2203 remote debugging; you can make a recording of the session and send it
2204 to someone else, who can then recreate the problem.
2206 * Speedups for remote debugging
2208 GDB includes speedups for downloading and stepping MIPS systems using
2209 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2210 and more efficient S-record downloading.
2212 * Memory use reductions and statistics collection
2214 GDB now uses less memory and reports statistics about memory usage.
2215 Try the `maint print statistics' command, for example.
2217 *** Changes in GDB-4.15:
2219 * Psymtabs for XCOFF
2221 The symbol reader for AIX GDB now uses partial symbol tables. This
2222 can greatly improve startup time, especially for large executables.
2224 * Remote targets use caching
2226 Remote targets now use a data cache to speed up communication with the
2227 remote side. The data cache could lead to incorrect results because
2228 it doesn't know about volatile variables, thus making it impossible to
2229 debug targets which use memory mapped I/O devices. `set remotecache
2230 off' turns the the data cache off.
2232 * Remote targets may have threads
2234 The standard remote protocol now includes support for multiple threads
2235 in the target system, using new protocol commands 'H' and 'T'. See
2236 gdb/remote.c for details.
2240 If GDB is configured with `--enable-netrom', then it will include
2241 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2242 acts as though it is a bank of ROM on the target board, but you can
2243 write into it over the network. GDB's support consists only of
2244 support for fast loading into the emulated ROM; to debug, you must use
2245 another protocol, such as standard remote protocol. The usual
2246 sequence is something like
2248 target nrom <netrom-hostname>
2250 target remote <netrom-hostname>:1235
2254 GDB now includes support for the Apple Macintosh, as a host only. It
2255 may be run as either an MPW tool or as a standalone application, and
2256 it can debug through the serial port. All the usual GDB commands are
2257 available, but to the target command, you must supply "serial" as the
2258 device type instead of "/dev/ttyXX". See mpw-README in the main
2259 directory for more information on how to build. The MPW configuration
2260 scripts */mpw-config.in support only a few targets, and only the
2261 mips-idt-ecoff target has been tested.
2265 GDB configuration now uses autoconf. This is not user-visible,
2266 but does simplify configuration and building.
2270 GDB now supports hpux10.
2272 *** Changes in GDB-4.14:
2274 * New native configurations
2276 x86 FreeBSD i[345]86-*-freebsd
2277 x86 NetBSD i[345]86-*-netbsd
2278 NS32k NetBSD ns32k-*-netbsd
2279 Sparc NetBSD sparc-*-netbsd
2283 A29K VxWorks a29k-*-vxworks
2284 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2285 CPU32 EST-300 emulator m68*-*-est*
2286 PowerPC ELF powerpc-*-elf
2289 * Alpha OSF/1 support for procfs
2291 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2292 possible to attach to running processes. As the mounting of the /proc
2293 filesystem is optional on the Alpha, GDB automatically determines
2294 the availability of /proc during startup. This can lead to problems
2295 if /proc is unmounted after GDB has been started.
2297 * Arguments to user-defined commands
2299 User commands may accept up to 10 arguments separated by whitespace.
2300 Arguments are accessed within the user command via $arg0..$arg9. A
2303 print $arg0 + $arg1 + $arg2
2305 To execute the command use:
2308 Defines the command "adder" which prints the sum of its three arguments.
2309 Note the arguments are text substitutions, so they may reference variables,
2310 use complex expressions, or even perform inferior function calls.
2312 * New `if' and `while' commands
2314 This makes it possible to write more sophisticated user-defined
2315 commands. Both commands take a single argument, which is the
2316 expression to evaluate, and must be followed by the commands to
2317 execute, one per line, if the expression is nonzero, the list being
2318 terminated by the word `end'. The `if' command list may include an
2319 `else' word, which causes the following commands to be executed only
2320 if the expression is zero.
2322 * Fortran source language mode
2324 GDB now includes partial support for Fortran 77. It will recognize
2325 Fortran programs and can evaluate a subset of Fortran expressions, but
2326 variables and functions may not be handled correctly. GDB will work
2327 with G77, but does not yet know much about symbols emitted by other
2330 * Better HPUX support
2332 Most debugging facilities now work on dynamic executables for HPPAs
2333 running hpux9 or later. You can attach to running dynamically linked
2334 processes, but by default the dynamic libraries will be read-only, so
2335 for instance you won't be able to put breakpoints in them. To change
2336 that behavior do the following before running the program:
2342 This will cause the libraries to be mapped private and read-write.
2343 To revert to the normal behavior, do this:
2349 You cannot set breakpoints or examine data in the library until after
2350 the library is loaded if the function/data symbols do not have
2353 GDB can now also read debug symbols produced by the HP C compiler on
2354 HPPAs (sorry, no C++, Fortran or 68k support).
2356 * Target byte order now dynamically selectable
2358 You can choose which byte order to use with a target system, via the
2359 commands "set endian big" and "set endian little", and you can see the
2360 current setting by using "show endian". You can also give the command
2361 "set endian auto", in which case GDB will use the byte order
2362 associated with the executable. Currently, only embedded MIPS
2363 configurations support dynamic selection of target byte order.
2365 * New DOS host serial code
2367 This version uses DPMI interrupts to handle buffered I/O, so you
2368 no longer need to run asynctsr when debugging boards connected to
2371 *** Changes in GDB-4.13:
2373 * New "complete" command
2375 This lists all the possible completions for the rest of the line, if it
2376 were to be given as a command itself. This is intended for use by emacs.
2378 * Trailing space optional in prompt
2380 "set prompt" no longer adds a space for you after the prompt you set. This
2381 allows you to set a prompt which ends in a space or one that does not.
2383 * Breakpoint hit counts
2385 "info break" now displays a count of the number of times the breakpoint
2386 has been hit. This is especially useful in conjunction with "ignore"; you
2387 can ignore a large number of breakpoint hits, look at the breakpoint info
2388 to see how many times the breakpoint was hit, then run again, ignoring one
2389 less than that number, and this will get you quickly to the last hit of
2392 * Ability to stop printing at NULL character
2394 "set print null-stop" will cause GDB to stop printing the characters of
2395 an array when the first NULL is encountered. This is useful when large
2396 arrays actually contain only short strings.
2398 * Shared library breakpoints
2400 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2401 breakpoints in shared libraries before the executable is run.
2403 * Hardware watchpoints
2405 There is a new hardware breakpoint for the watch command for sparclite
2406 targets. See gdb/sparclite/hw_breakpoint.note.
2408 Hardware watchpoints are also now supported under GNU/Linux.
2412 Annotations have been added. These are for use with graphical interfaces,
2413 and are still experimental. Currently only gdba.el uses these.
2415 * Improved Irix 5 support
2417 GDB now works properly with Irix 5.2.
2419 * Improved HPPA support
2421 GDB now works properly with the latest GCC and GAS.
2423 * New native configurations
2425 Sequent PTX4 i[34]86-sequent-ptx4
2426 HPPA running OSF/1 hppa*-*-osf*
2427 Atari TT running SVR4 m68*-*-sysv4*
2428 RS/6000 LynxOS rs6000-*-lynxos*
2432 OS/9000 i[34]86-*-os9k
2433 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2436 * Hitachi SH7000 and E7000-PC ICE support
2438 There is now support for communicating with the Hitachi E7000-PC ICE.
2439 This is available automatically when GDB is configured for the SH.
2443 As usual, a variety of small fixes and improvements, both generic
2444 and configuration-specific. See the ChangeLog for more detail.
2446 *** Changes in GDB-4.12:
2448 * Irix 5 is now supported
2452 GDB-4.12 on the HPPA has a number of changes which make it unable
2453 to debug the output from the currently released versions of GCC and
2454 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2455 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2456 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2459 *** Changes in GDB-4.11:
2461 * User visible changes:
2465 The "set remotedebug" option is now consistent between the mips remote
2466 target, remote targets using the gdb-specific protocol, UDI (AMD's
2467 debug protocol for the 29k) and the 88k bug monitor. It is now an
2468 integer specifying a debug level (normally 0 or 1, but 2 means more
2469 debugging info for the mips target).
2471 * DEC Alpha native support
2473 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2474 debug info, but GDB works fairly well with the DEC compiler and should
2475 work with a future GCC release. See the README file for a few
2476 Alpha-specific notes.
2478 * Preliminary thread implementation
2480 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2482 * LynxOS native and target support for 386
2484 This release has been hosted on LynxOS 2.2, and also can be configured
2485 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2488 * Improvements in C++ mangling/demangling.
2490 This release has much better g++ debugging, specifically in name
2491 mangling/demangling, virtual function calls, print virtual table,
2492 call methods, ...etc.
2494 *** Changes in GDB-4.10:
2496 * User visible changes:
2498 Remote debugging using the GDB-specific (`target remote') protocol now
2499 supports the `load' command. This is only useful if you have some
2500 other way of getting the stub to the target system, and you can put it
2501 somewhere in memory where it won't get clobbered by the download.
2503 Filename completion now works.
2505 When run under emacs mode, the "info line" command now causes the
2506 arrow to point to the line specified. Also, "info line" prints
2507 addresses in symbolic form (as well as hex).
2509 All vxworks based targets now support a user settable option, called
2510 vxworks-timeout. This option represents the number of seconds gdb
2511 should wait for responses to rpc's. You might want to use this if
2512 your vxworks target is, perhaps, a slow software simulator or happens
2513 to be on the far side of a thin network line.
2517 This release contains support for using a DEC alpha as a GDB host for
2518 cross debugging. Native alpha debugging is not supported yet.
2521 *** Changes in GDB-4.9:
2525 This is the first GDB release which is accompanied by a matching testsuite.
2526 The testsuite requires installation of dejagnu, which should be available
2527 via ftp from most sites that carry GNU software.
2531 'Cfront' style demangling has had its name changed to 'ARM' style, to
2532 emphasize that it was written from the specifications in the C++ Annotated
2533 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2534 disclaimers, it still generated too much confusion with users attempting to
2535 use gdb with AT&T cfront.
2539 GDB now uses a standard remote interface to a simulator library.
2540 So far, the library contains simulators for the Zilog Z8001/2, the
2541 Hitachi H8/300, H8/500 and Super-H.
2543 * New targets supported
2545 H8/300 simulator h8300-hitachi-hms or h8300hms
2546 H8/500 simulator h8500-hitachi-hms or h8500hms
2547 SH simulator sh-hitachi-hms or sh
2548 Z8000 simulator z8k-zilog-none or z8ksim
2549 IDT MIPS board over serial line mips-idt-ecoff
2551 Cross-debugging to GO32 targets is supported. It requires a custom
2552 version of the i386-stub.c module which is integrated with the
2553 GO32 memory extender.
2555 * New remote protocols
2557 MIPS remote debugging protocol.
2559 * New source languages supported
2561 This version includes preliminary support for Chill, a Pascal like language
2562 used by telecommunications companies. Chill support is also being integrated
2563 into the GNU compiler, but we don't know when it will be publically available.
2566 *** Changes in GDB-4.8:
2568 * HP Precision Architecture supported
2570 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2571 version of this support was available as a set of patches from the
2572 University of Utah. GDB does not support debugging of programs
2573 compiled with the HP compiler, because HP will not document their file
2574 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2575 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2577 Many problems in the preliminary version have been fixed.
2579 * Faster and better demangling
2581 We have improved template demangling and fixed numerous bugs in the GNU style
2582 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2583 character types (wchar_t) are now supported. Demangling of each symbol is now
2584 only done once, and is cached when the symbol table for a file is read in.
2585 This results in a small increase in memory usage for C programs, a moderate
2586 increase in memory usage for C++ programs, and a fantastic speedup in
2589 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2590 from the specifications in the Annotated Reference Manual, which AT&T's
2591 compiler does not actually implement.
2593 * G++ multiple inheritance compiler problem
2595 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2596 inheritance lattices was reworked to properly discover ambiguities. We
2597 recently found an example which causes this new algorithm to fail in a
2598 very subtle way, producing bad debug information for those classes.
2599 The file 'gcc.patch' (in this directory) can be applied to gcc to
2600 circumvent the problem. A future GCC release will contain a complete
2603 The previous G++ debug info problem (mentioned below for the gdb-4.7
2604 release) is fixed in gcc version 2.3.2.
2606 * Improved configure script
2608 The `configure' script will now attempt to guess your system type if
2609 you don't supply a host system type. The old scheme of supplying a
2610 host system triplet is preferable over using this. All the magic is
2611 done in the new `config.guess' script. Examine it for details.
2613 We have also brought our configure script much more in line with the FSF's
2614 version. It now supports the --with-xxx options. In particular,
2615 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2616 The resulting GDB will not be able to read arbitrary object file formats --
2617 only the format ``expected'' to be used on the configured target system.
2618 We hope to make this the default in a future release.
2620 * Documentation improvements
2622 There's new internal documentation on how to modify GDB, and how to
2623 produce clean changes to the code. We implore people to read it
2624 before submitting changes.
2626 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2627 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2628 `info' files are also provided. To build `info' files from scratch,
2629 you will need the latest `makeinfo' release, which will be available in
2630 a future texinfo-X.Y release.
2632 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2633 We're not sure exactly which versions have this problem, but it has
2634 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2635 or better. If that isn't possible, there is a patch in
2636 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2637 around this problem.
2641 GDB now supports array constants that can be used in expressions typed in by
2642 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2643 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2646 The new directory `gdb/sparclite' contains a program that demonstrates
2647 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2649 * New native hosts supported
2651 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2652 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2654 * New targets supported
2656 AMD 29k family via UDI a29k-amd-udi or udi29k
2658 * New file formats supported
2660 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2661 HPUX core files, and SCO 3.2v2 core files.
2665 Attaching to processes now works again; thanks for the many bug reports.
2667 We have also stomped on a bunch of core dumps caused by
2668 printf_filtered("%s") problems.
2670 We eliminated a copyright problem on the rpc and ptrace header files
2671 for VxWorks, which was discovered at the last minute during the 4.7
2672 release. You should now be able to build a VxWorks GDB.
2674 You can now interrupt gdb while an attached process is running. This
2675 will cause the attached process to stop, and give control back to GDB.
2677 We fixed problems caused by using too many file descriptors
2678 for reading symbols from object files and libraries. This was
2679 especially a problem for programs that used many (~100) shared
2682 The `step' command now only enters a subroutine if there is line number
2683 information for the subroutine. Otherwise it acts like the `next'
2684 command. Previously, `step' would enter subroutines if there was
2685 any debugging information about the routine. This avoids problems
2686 when using `cc -g1' on MIPS machines.
2688 * Internal improvements
2690 GDB's internal interfaces have been improved to make it easier to support
2691 debugging of multiple languages in the future.
2693 GDB now uses a common structure for symbol information internally.
2694 Minimal symbols (derived from linkage symbols in object files), partial
2695 symbols (from a quick scan of debug information), and full symbols
2696 contain a common subset of information, making it easier to write
2697 shared code that handles any of them.
2699 * New command line options
2701 We now accept --silent as an alias for --quiet.
2705 The memory-mapped-malloc library is now licensed under the GNU Library
2706 General Public License.
2708 *** Changes in GDB-4.7:
2710 * Host/native/target split
2712 GDB has had some major internal surgery to untangle the support for
2713 hosts and remote targets. Now, when you configure GDB for a remote
2714 target, it will no longer load in all of the support for debugging
2715 local programs on the host. When fully completed and tested, this will
2716 ensure that arbitrary host/target combinations are possible.
2718 The primary conceptual shift is to separate the non-portable code in
2719 GDB into three categories. Host specific code is required any time GDB
2720 is compiled on that host, regardless of the target. Target specific
2721 code relates to the peculiarities of the target, but can be compiled on
2722 any host. Native specific code is everything else: it can only be
2723 built when the host and target are the same system. Child process
2724 handling and core file support are two common `native' examples.
2726 GDB's use of /proc for controlling Unix child processes is now cleaner.
2727 It has been split out into a single module under the `target_ops' vector,
2728 plus two native-dependent functions for each system that uses /proc.
2730 * New hosts supported
2732 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2733 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2734 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2736 * New targets supported
2738 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2739 68030 and CPU32 m68030-*-*, m68332-*-*
2741 * New native hosts supported
2743 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2744 (386bsd is not well tested yet)
2745 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2747 * New file formats supported
2749 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2750 supports reading of `a.out.adobe' object files, which are an a.out
2751 format extended with minimal information about multiple sections.
2755 `show copying' is the same as the old `info copying'.
2756 `show warranty' is the same as `info warrantee'.
2757 These were renamed for consistency. The old commands continue to work.
2759 `info handle' is a new alias for `info signals'.
2761 You can now define pre-command hooks, which attach arbitrary command
2762 scripts to any command. The commands in the hook will be executed
2763 prior to the user's command. You can also create a hook which will be
2764 executed whenever the program stops. See gdb.texinfo.
2768 We now deal with Cfront style name mangling, and can even extract type
2769 info from mangled symbols. GDB can automatically figure out which
2770 symbol mangling style your C++ compiler uses.
2772 Calling of methods and virtual functions has been improved as well.
2776 The crash that occured when debugging Sun Ansi-C compiled binaries is
2777 fixed. This was due to mishandling of the extra N_SO stabs output
2780 We also finally got Ultrix 4.2 running in house, and fixed core file
2781 support, with help from a dozen people on the net.
2783 John M. Farrell discovered that the reason that single-stepping was so
2784 slow on all of the Mips based platforms (primarily SGI and DEC) was
2785 that we were trying to demangle and lookup a symbol used for internal
2786 purposes on every instruction that was being stepped through. Changing
2787 the name of that symbol so that it couldn't be mistaken for a C++
2788 mangled symbol sped things up a great deal.
2790 Rich Pixley sped up symbol lookups in general by getting much smarter
2791 about when C++ symbol mangling is necessary. This should make symbol
2792 completion (TAB on the command line) much faster. It's not as fast as
2793 we'd like, but it's significantly faster than gdb-4.6.
2797 A new user controllable variable 'call_scratch_address' can
2798 specify the location of a scratch area to be used when GDB
2799 calls a function in the target. This is necessary because the
2800 usual method of putting the scratch area on the stack does not work
2801 in systems that have separate instruction and data spaces.
2803 We integrated changes to support the 29k UDI (Universal Debugger
2804 Interface), but discovered at the last minute that we didn't have all
2805 of the appropriate copyright paperwork. We are working with AMD to
2806 resolve this, and hope to have it available soon.
2810 We have sped up the remote serial line protocol, especially for targets
2811 with lots of registers. It now supports a new `expedited status' ('T')
2812 message which can be used in place of the existing 'S' status message.
2813 This allows the remote stub to send only the registers that GDB
2814 needs to make a quick decision about single-stepping or conditional
2815 breakpoints, eliminating the need to fetch the entire register set for
2816 each instruction being stepped through.
2818 The GDB remote serial protocol now implements a write-through cache for
2819 registers, only re-reading the registers if the target has run.
2821 There is also a new remote serial stub for SPARC processors. You can
2822 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2823 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2824 processor with a serial port.
2828 Configure.in files have become much easier to read and modify. A new
2829 `table driven' format makes it more obvious what configurations are
2830 supported, and what files each one uses.
2834 There is a new opcodes library which will eventually contain all of the
2835 disassembly routines and opcode tables. At present, it only contains
2836 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2837 disassembler (binutils/objdump) to share these routines.
2839 The libiberty library is now copylefted under the GNU Library General
2840 Public License. This allows more liberal use, and was done so libg++
2841 can use it. This makes no difference to GDB, since the Library License
2842 grants all the rights from the General Public License.
2846 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2847 reference to the stabs symbol info used by the debugger. It is (as far
2848 as we know) the only published document on this fascinating topic. We
2849 encourage you to read it, compare it to the stabs information on your
2850 system, and send improvements on the document in general (to
2851 bug-gdb@prep.ai.mit.edu).
2853 And, of course, many bugs have been fixed.
2856 *** Changes in GDB-4.6:
2858 * Better support for C++ function names
2860 GDB now accepts as input the "demangled form" of C++ overloaded function
2861 names and member function names, and can do command completion on such names
2862 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2863 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2864 Make use of command completion, it is your friend.
2866 GDB also now accepts a variety of C++ mangled symbol formats. They are
2867 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2868 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2869 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2870 for the list of formats.
2872 * G++ symbol mangling problem
2874 Recent versions of gcc have a bug in how they emit debugging information for
2875 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2876 directory) can be applied to gcc to fix the problem. Alternatively, if you
2877 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2878 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2879 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2882 * New 'maintenance' command
2884 All of the commands related to hacking GDB internals have been moved out of
2885 the main command set, and now live behind the 'maintenance' command. This
2886 can also be abbreviated as 'mt'. The following changes were made:
2888 dump-me -> maintenance dump-me
2889 info all-breakpoints -> maintenance info breakpoints
2890 printmsyms -> maintenance print msyms
2891 printobjfiles -> maintenance print objfiles
2892 printpsyms -> maintenance print psymbols
2893 printsyms -> maintenance print symbols
2895 The following commands are new:
2897 maintenance demangle Call internal GDB demangler routine to
2898 demangle a C++ link name and prints the result.
2899 maintenance print type Print a type chain for a given symbol
2901 * Change to .gdbinit file processing
2903 We now read the $HOME/.gdbinit file before processing the argv arguments
2904 (e.g. reading symbol files or core files). This allows global parameters to
2905 be set, which will apply during the symbol reading. The ./.gdbinit is still
2906 read after argv processing.
2908 * New hosts supported
2910 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
2912 GNU/Linux support i386-unknown-linux or linux
2914 We are also including code to support the HP/PA running BSD and HPUX. This
2915 is almost guaranteed not to work, as we didn't have time to test or build it
2916 for this release. We are including it so that the more adventurous (or
2917 masochistic) of you can play with it. We also had major problems with the
2918 fact that the compiler that we got from HP doesn't support the -g option.
2921 * New targets supported
2923 Hitachi H8/300 h8300-hitachi-hms or h8300hms
2925 * More smarts about finding #include files
2927 GDB now remembers the compilation directory for all include files, and for
2928 all files from which C is generated (like yacc and lex sources). This
2929 greatly improves GDB's ability to find yacc/lex sources, and include files,
2930 especially if you are debugging your program from a directory different from
2931 the one that contains your sources.
2933 We also fixed a bug which caused difficulty with listing and setting
2934 breakpoints in include files which contain C code. (In the past, you had to
2935 try twice in order to list an include file that you hadn't looked at before.)
2937 * Interesting infernals change
2939 GDB now deals with arbitrary numbers of sections, where the symbols for each
2940 section must be relocated relative to that section's landing place in the
2941 target's address space. This work was needed to support ELF with embedded
2942 stabs used by Solaris-2.0.
2944 * Bug fixes (of course!)
2946 There have been loads of fixes for the following things:
2947 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2948 i960, stabs, DOS(GO32), procfs, etc...
2950 See the ChangeLog for details.
2952 *** Changes in GDB-4.5:
2954 * New machines supported (host and target)
2956 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2958 SGI Irix-4.x mips-sgi-irix4 or iris4
2960 * New malloc package
2962 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2963 Mmalloc is capable of handling mutiple heaps of memory. It is also
2964 capable of saving a heap to a file, and then mapping it back in later.
2965 This can be used to greatly speedup the startup of GDB by using a
2966 pre-parsed symbol table which lives in a mmalloc managed heap. For
2967 more details, please read mmalloc/mmalloc.texi.
2971 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2972 'help info proc' for details.
2974 * MIPS ecoff symbol table format
2976 The code that reads MIPS symbol table format is now supported on all hosts.
2977 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2980 * File name changes for MS-DOS
2982 Many files in the config directories have been renamed to make it easier to
2983 support GDB on MS-DOSe systems (which have very restrictive file name
2984 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2985 environment) is close to working but has some remaining problems. Note
2986 that debugging of DOS programs is not supported, due to limitations
2987 in the ``operating system'', but it can be used to host cross-debugging.
2989 * Cross byte order fixes
2991 Many fixes have been made to support cross debugging of Sparc and MIPS
2992 targets from hosts whose byte order differs.
2994 * New -mapped and -readnow options
2996 If memory-mapped files are available on your system through the 'mmap'
2997 system call, you can use the -mapped option on the `file' or
2998 `symbol-file' commands to cause GDB to write the symbols from your
2999 program into a reusable file. If the program you are debugging is
3000 called `/path/fred', the mapped symbol file will be `./fred.syms'.
3001 Future GDB debugging sessions will notice the presence of this file,
3002 and will quickly map in symbol information from it, rather than reading
3003 the symbol table from the executable program. Using the '-mapped'
3004 option in a GDB `file' or `symbol-file' command has the same effect as
3005 starting GDB with the '-mapped' command-line option.
3007 You can cause GDB to read the entire symbol table immediately by using
3008 the '-readnow' option with any of the commands that load symbol table
3009 information (or on the GDB command line). This makes the command
3010 slower, but makes future operations faster.
3012 The -mapped and -readnow options are typically combined in order to
3013 build a `fred.syms' file that contains complete symbol information.
3014 A simple GDB invocation to do nothing but build a `.syms' file for future
3017 gdb -batch -nx -mapped -readnow programname
3019 The `.syms' file is specific to the host machine on which GDB is run.
3020 It holds an exact image of GDB's internal symbol table. It cannot be
3021 shared across multiple host platforms.
3023 * longjmp() handling
3025 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
3026 siglongjmp() without losing control. This feature has not yet been ported to
3027 all systems. It currently works on many 386 platforms, all MIPS-based
3028 platforms (SGI, DECstation, etc), and Sun3/4.
3032 Preliminary work has been put in to support the new Solaris OS from Sun. At
3033 this time, it can control and debug processes, but it is not capable of
3038 As always, many many bug fixes. The major areas were with g++, and mipsread.
3039 People using the MIPS-based platforms should experience fewer mysterious
3040 crashes and trashed symbol tables.
3042 *** Changes in GDB-4.4:
3044 * New machines supported (host and target)
3046 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3048 BSD Reno on Vax vax-dec-bsd
3049 Ultrix on Vax vax-dec-ultrix
3051 * New machines supported (target)
3053 AMD 29000 embedded, using EBMON a29k-none-none
3057 GDB continues to improve its handling of C++. `References' work better.
3058 The demangler has also been improved, and now deals with symbols mangled as
3059 per the Annotated C++ Reference Guide.
3061 GDB also now handles `stabs' symbol information embedded in MIPS
3062 `ecoff' symbol tables. Since the ecoff format was not easily
3063 extensible to handle new languages such as C++, this appeared to be a
3064 good way to put C++ debugging info into MIPS binaries. This option
3065 will be supported in the GNU C compiler, version 2, when it is
3068 * New features for SVR4
3070 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
3071 shared libraries. Debugging dynamically linked programs should present
3072 only minor differences from debugging statically linked programs.
3074 The `info proc' command will print out information about any process
3075 on an SVR4 system (including the one you are debugging). At the moment,
3076 it prints the address mappings of the process.
3078 If you bring up GDB on another SVR4 system, please send mail to
3079 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
3081 * Better dynamic linking support in SunOS
3083 Reading symbols from shared libraries which contain debugging symbols
3084 now works properly. However, there remain issues such as automatic
3085 skipping of `transfer vector' code during function calls, which
3086 make it harder to debug code in a shared library, than to debug the
3087 same code linked statically.
3091 GDB is now using the latest `getopt' routines from the FSF. This
3092 version accepts the -- prefix for options with long names. GDB will
3093 continue to accept the old forms (-option and +option) as well.
3094 Various single letter abbreviations for options have been explicity
3095 added to the option table so that they won't get overshadowed in the
3096 future by other options that begin with the same letter.
3100 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
3101 Many assorted bugs have been handled. Many more remain to be handled.
3102 See the various ChangeLog files (primarily in gdb and bfd) for details.
3105 *** Changes in GDB-4.3:
3107 * New machines supported (host and target)
3109 Amiga 3000 running Amix m68k-cbm-svr4 or amix
3110 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
3111 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
3113 * Almost SCO Unix support
3115 We had hoped to support:
3116 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
3117 (except for core file support), but we discovered very late in the release
3118 that it has problems with process groups that render gdb unusable. Sorry
3119 about that. I encourage people to fix it and post the fixes.
3121 * Preliminary ELF and DWARF support
3123 GDB can read ELF object files on System V Release 4, and can handle
3124 debugging records for C, in DWARF format, in ELF files. This support
3125 is preliminary. If you bring up GDB on another SVR4 system, please
3126 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
3131 GDB now uses the latest `readline' library. One user-visible change
3132 is that two tabs will list possible command completions, which previously
3133 required typing M-? (meta-question mark, or ESC ?).
3137 The `stepi' bug that many of you noticed has been squashed.
3138 Many bugs in C++ have been handled. Many more remain to be handled.
3139 See the various ChangeLog files (primarily in gdb and bfd) for details.
3141 * State of the MIPS world (in case you wondered):
3143 GDB can understand the symbol tables emitted by the compilers
3144 supplied by most vendors of MIPS-based machines, including DEC. These
3145 symbol tables are in a format that essentially nobody else uses.
3147 Some versions of gcc come with an assembler post-processor called
3148 mips-tfile. This program is required if you want to do source-level
3149 debugging of gcc-compiled programs. I believe FSF does not ship
3150 mips-tfile with gcc version 1, but it will eventually come with gcc
3153 Debugging of g++ output remains a problem. g++ version 1.xx does not
3154 really support it at all. (If you're lucky, you should be able to get
3155 line numbers and stack traces to work, but no parameters or local
3156 variables.) With some work it should be possible to improve the
3159 When gcc version 2 is released, you will have somewhat better luck.
3160 However, even then you will get confusing results for inheritance and
3163 We will eventually provide full debugging of g++ output on
3164 DECstations. This will probably involve some kind of stabs-in-ecoff
3165 encapulation, but the details have not been worked out yet.
3168 *** Changes in GDB-4.2:
3170 * Improved configuration
3172 Only one copy of `configure' exists now, and it is not self-modifying.
3173 Porting BFD is simpler.
3177 The `step' and `next' commands now only stop at the first instruction
3178 of a source line. This prevents the multiple stops that used to occur
3179 in switch statements, for-loops, etc. `Step' continues to stop if a
3180 function that has debugging information is called within the line.
3184 Lots of small bugs fixed. More remain.
3186 * New host supported (not target)
3188 Intel 386 PC clone running Mach i386-none-mach
3191 *** Changes in GDB-4.1:
3193 * Multiple source language support
3195 GDB now has internal scaffolding to handle several source languages.
3196 It determines the type of each source file from its filename extension,
3197 and will switch expression parsing and number formatting to match the
3198 language of the function in the currently selected stack frame.
3199 You can also specifically set the language to be used, with
3200 `set language c' or `set language modula-2'.
3204 GDB now has preliminary support for the GNU Modula-2 compiler,
3205 currently under development at the State University of New York at
3206 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3207 continue through the fall of 1991 and into 1992.
3209 Other Modula-2 compilers are currently not supported, and attempting to
3210 debug programs compiled with them will likely result in an error as the
3211 symbol table is read. Feel free to work on it, though!
3213 There are hooks in GDB for strict type checking and range checking,
3214 in the `Modula-2 philosophy', but they do not currently work.
3218 GDB can now write to executable and core files (e.g. patch
3219 a variable's value). You must turn this switch on, specify
3220 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3221 by assigning a new value to a variable. Modifications take
3224 * Automatic SunOS shared library reading
3226 When you run your program, GDB automatically determines where its
3227 shared libraries (if any) have been loaded, and reads their symbols.
3228 The `share' command is no longer needed. This also works when
3229 examining core files.
3233 You can specify the number of lines that the `list' command shows.
3236 * New machines supported (host and target)
3238 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3239 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3240 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3242 * New hosts supported (not targets)
3244 IBM RT/PC: romp-ibm-aix or rtpc
3246 * New targets supported (not hosts)
3248 AMD 29000 embedded with COFF a29k-none-coff
3249 AMD 29000 embedded with a.out a29k-none-aout
3250 Ultracomputer remote kernel debug a29k-nyu-kern
3252 * New remote interfaces
3258 *** Changes in GDB-4.0:
3262 Wide output is wrapped at good places to make the output more readable.
3264 Gdb now supports cross-debugging from a host machine of one type to a
3265 target machine of another type. Communication with the target system
3266 is over serial lines. The ``target'' command handles connecting to the
3267 remote system; the ``load'' command will download a program into the
3268 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3269 also supports debugging of realtime processes running under VxWorks,
3270 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3271 stub on the target system.
3273 New CPUs supported include the AMD 29000 and Intel 960.
3275 GDB now reads object files and symbol tables via a ``binary file''
3276 library, which allows a single copy of GDB to debug programs of multiple
3277 object file types such as a.out and coff.
3279 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3280 refcard.dvi and refcard.ps are available to format it).
3283 * Control-Variable user interface simplified
3285 All variables that control the operation of the debugger can be set
3286 by the ``set'' command, and displayed by the ``show'' command.
3288 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3289 ``Show prompt'' produces the response:
3290 Gdb's prompt is new-gdb=>.
3292 What follows are the NEW set commands. The command ``help set'' will
3293 print a complete list of old and new set commands. ``help set FOO''
3294 will give a longer description of the variable FOO. ``show'' will show
3295 all of the variable descriptions and their current settings.
3297 confirm on/off: Enables warning questions for operations that are
3298 hard to recover from, e.g. rerunning the program while
3299 it is already running. Default is ON.
3301 editing on/off: Enables EMACS style command line editing
3302 of input. Previous lines can be recalled with
3303 control-P, the current line can be edited with control-B,
3304 you can search for commands with control-R, etc.
3307 history filename NAME: NAME is where the gdb command history
3308 will be stored. The default is .gdb_history,
3309 or the value of the environment variable
3312 history size N: The size, in commands, of the command history. The
3313 default is 256, or the value of the environment variable
3316 history save on/off: If this value is set to ON, the history file will
3317 be saved after exiting gdb. If set to OFF, the
3318 file will not be saved. The default is OFF.
3320 history expansion on/off: If this value is set to ON, then csh-like
3321 history expansion will be performed on
3322 command line input. The default is OFF.
3324 radix N: Sets the default radix for input and output. It can be set
3325 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3326 in the current radix, so "set radix 10" is always a no-op.
3328 height N: This integer value is the number of lines on a page. Default
3329 is 24, the current `stty rows'' setting, or the ``li#''
3330 setting from the termcap entry matching the environment
3333 width N: This integer value is the number of characters on a line.
3334 Default is 80, the current `stty cols'' setting, or the ``co#''
3335 setting from the termcap entry matching the environment
3338 Note: ``set screensize'' is obsolete. Use ``set height'' and
3339 ``set width'' instead.
3341 print address on/off: Print memory addresses in various command displays,
3342 such as stack traces and structure values. Gdb looks
3343 more ``symbolic'' if you turn this off; it looks more
3344 ``machine level'' with it on. Default is ON.
3346 print array on/off: Prettyprint arrays. New convenient format! Default
3349 print demangle on/off: Print C++ symbols in "source" form if on,
3352 print asm-demangle on/off: Same, for assembler level printouts
3355 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3358 * Support for Epoch Environment.
3360 The epoch environment is a version of Emacs v18 with windowing. One
3361 new command, ``inspect'', is identical to ``print'', except that if you
3362 are running in the epoch environment, the value is printed in its own
3366 * Support for Shared Libraries
3368 GDB can now debug programs and core files that use SunOS shared libraries.
3369 Symbols from a shared library cannot be referenced
3370 before the shared library has been linked with the program (this
3371 happens after you type ``run'' and before the function main() is entered).
3372 At any time after this linking (including when examining core files
3373 from dynamically linked programs), gdb reads the symbols from each
3374 shared library when you type the ``sharedlibrary'' command.
3375 It can be abbreviated ``share''.
3377 sharedlibrary REGEXP: Load shared object library symbols for files
3378 matching a unix regular expression. No argument
3379 indicates to load symbols for all shared libraries.
3381 info sharedlibrary: Status of loaded shared libraries.
3386 A watchpoint stops execution of a program whenever the value of an
3387 expression changes. Checking for this slows down execution
3388 tremendously whenever you are in the scope of the expression, but is
3389 quite useful for catching tough ``bit-spreader'' or pointer misuse
3390 problems. Some machines such as the 386 have hardware for doing this
3391 more quickly, and future versions of gdb will use this hardware.
3393 watch EXP: Set a watchpoint (breakpoint) for an expression.
3395 info watchpoints: Information about your watchpoints.
3397 delete N: Deletes watchpoint number N (same as breakpoints).
3398 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3399 enable N: Re-enables watchpoint number N (same as breakpoints).
3402 * C++ multiple inheritance
3404 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3407 * C++ exception handling
3409 Gdb now supports limited C++ exception handling. Besides the existing
3410 ability to breakpoint on an exception handler, gdb can breakpoint on
3411 the raising of an exception (before the stack is peeled back to the
3414 catch FOO: If there is a FOO exception handler in the dynamic scope,
3415 set a breakpoint to catch exceptions which may be raised there.
3416 Multiple exceptions (``catch foo bar baz'') may be caught.
3418 info catch: Lists all exceptions which may be caught in the
3419 current stack frame.
3422 * Minor command changes
3424 The command ``call func (arg, arg, ...)'' now acts like the print
3425 command, except it does not print or save a value if the function's result
3426 is void. This is similar to dbx usage.
3428 The ``up'' and ``down'' commands now always print the frame they end up
3429 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3430 frames without printing.
3432 * New directory command
3434 'dir' now adds directories to the FRONT of the source search path.
3435 The path starts off empty. Source files that contain debug information
3436 about the directory in which they were compiled can be found even
3437 with an empty path; Sun CC and GCC include this information. If GDB can't
3438 find your source file in the current directory, type "dir .".
3440 * Configuring GDB for compilation
3442 For normal use, type ``./configure host''. See README or gdb.texinfo
3445 GDB now handles cross debugging. If you are remotely debugging between
3446 two different machines, type ``./configure host -target=targ''.
3447 Host is the machine where GDB will run; targ is the machine
3448 where the program that you are debugging will run.