1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.8
6 * GDB now supports multiple function calling conventions according to the
7 DWARF-2 DW_AT_calling_convention function attribute.
9 * The SH target utilizes the aforementioned change to distinguish between gcc
10 and Renesas calling convention. It also adds the new CLI commands
11 `set/show sh calling-convention'.
13 * GDB can now read compressed debug sections, as produced by GNU gold
14 with the --compress-debug-sections=zlib flag.
16 * 64-bit core files are now supported on AIX.
18 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
19 which will be allocated using malloc later in program execution.
21 * The qXfer:libraries:read remote procotol packet now allows passing a
22 list of section offsets.
24 * New features in the GDB remote stub, gdbserver
26 - The "--wrapper" command-line argument tells gdbserver to use a
27 wrapper program to launch programs for debugging.
33 Display timestamps with GDB debugging output.
38 Use a wrapper program to launch programs for debugging.
40 set multiple-symbols (all|ask|cancel)
42 The value of this variable can be changed to adjust the debugger behavior
43 when an expression or a breakpoint location contains an ambiguous symbol
44 name (an overloaded function name, for instance).
46 *** Changes in GDB 6.8
48 * New native configurations
50 NetBSD/hppa hppa*-*netbsd*
51 Xtensa GNU/Linux xtensa*-*-linux*
55 NetBSD/hppa hppa*-*-netbsd*
56 Xtensa GNU/Lunux xtensa*-*-linux*
58 * Change in command line behavior -- corefiles vs. process ids.
60 When the '-p NUMBER' or '--pid NUMBER' options are used, and
61 attaching to process NUMBER fails, GDB no longer attempts to open a
62 core file named NUMBER. Attaching to a program using the -c option
63 is no longer supported. Instead, use the '-p' or '--pid' options.
65 * GDB can now be built as a native debugger for debugging Windows x86
66 (mingw32) Portable Executable (PE) programs.
68 * Pending breakpoints no longer change their number when their address
71 * GDB now supports breakpoints with multiple locations,
72 including breakpoints on C++ constructors, inside C++ templates,
73 and in inlined functions.
75 * GDB's ability to debug optimized code has been improved. GDB more
76 accurately identifies function bodies and lexical blocks that occupy
77 more than one contiguous range of addresses.
79 * Target descriptions can now describe registers for PowerPC.
81 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
82 registers on PowerPC targets.
84 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
85 targets even when the libthread_db library is not available.
87 * The GDB remote stub, gdbserver, now supports the new file transfer
88 commands (remote put, remote get, and remote delete).
90 * The GDB remote stub, gdbserver, now supports run and attach in
93 * hppa*64*-*-hpux11* target broken
94 The debugger is unable to start a program and fails with the following
95 error: "Error trying to get information about dynamic linker".
96 The gdb-6.7 release is also affected.
98 * GDB now supports the --enable-targets= configure option to allow
99 building a single GDB executable that supports multiple remote
100 target architectures.
102 * GDB now supports debugging C and C++ programs which use the
103 Decimal Floating Point extension. In addition, the PowerPC target
104 now has a set of pseudo-registers to inspect decimal float values
105 stored in two consecutive float registers.
107 * The -break-insert MI command can optionally create pending
110 * Improved support for debugging Ada
111 Many improvements to the Ada language support have been made. These
113 - Better support for Ada2005 interface types
114 - Improved handling of arrays and slices in general
115 - Better support for Taft-amendment types
116 - The '{type} ADDRESS' expression is now allowed on the left hand-side
118 - Improved command completion in Ada
123 set print frame-arguments (all|scalars|none)
124 show print frame-arguments
125 The value of this variable can be changed to control which argument
126 values should be printed by the debugger when displaying a frame.
131 Transfer files to and from a remote target, and delete remote files.
138 Transfer files to and from a remote target, and delete remote files.
147 Open, close, read, write, and delete files on the remote system.
149 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
153 Attach to an existing process on the remote system, in extended-remote
157 Run a new process on the remote system, in extended-remote mode.
159 *** Changes in GDB 6.7
161 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
162 bfd, libiberty and opcodes, as revealed by static analysis donated by
163 Coverity, Inc. (http://scan.coverity.com).
165 * When looking up multiply-defined global symbols, GDB will now prefer the
166 symbol definition in the current shared library if it was built using the
167 -Bsymbolic linker option.
169 * When the Text User Interface (TUI) is not configured, GDB will now
170 recognize the -tui command-line option and print a message that the TUI
173 * The GDB remote stub, gdbserver, now has lower overhead for high
174 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
176 * GDB for MIPS targets now autodetects whether a remote target provides
177 32-bit or 64-bit register values.
179 * Support for C++ member pointers has been improved.
181 * GDB now understands XML target descriptions, which specify the
182 target's overall architecture. GDB can read a description from
183 a local file or over the remote serial protocol.
185 * Vectors of single-byte data use a new integer type which is not
186 automatically displayed as character or string data.
188 * The /s format now works with the print command. It displays
189 arrays of single-byte integers and pointers to single-byte integers
192 * Target descriptions can now describe target-specific registers,
193 for architectures which have implemented the support (currently
194 only ARM, M68K, and MIPS).
196 * GDB and the GDB remote stub, gdbserver, now support the XScale
199 * The GDB remote stub, gdbserver, has been updated to support
200 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
201 has been rewritten to use the standard GDB remote protocol.
203 * GDB can now step into C++ functions which are called through thunks.
205 * GDB for the Cell/B.E. SPU now supports overlay debugging.
207 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
208 layout. It also supports a TextSeg= and DataSeg= response when only
209 segment base addresses (rather than offsets) are available.
211 * The /i format now outputs any trailing branch delay slot instructions
212 immediately following the last instruction within the count specified.
214 * The GDB remote protocol "T" stop reply packet now supports a
215 "library" response. Combined with the new "qXfer:libraries:read"
216 packet, this response allows GDB to debug shared libraries on targets
217 where the operating system manages the list of loaded libraries (e.g.
218 Windows and SymbianOS).
220 * The GDB remote stub, gdbserver, now supports dynamic link libraries
221 (DLLs) on Windows and Windows CE targets.
223 * GDB now supports a faster verification that a .debug file matches its binary
224 according to its build-id signature, if the signature is present.
230 Enable or disable hardware flow control (RTS/CTS) on the serial port
231 when debugging using remote targets.
233 set mem inaccessible-by-default
234 show mem inaccessible-by-default
235 If the target supplies a memory map, for instance via the remote
236 protocol's "qXfer:memory-map:read" packet, setting this variable
237 prevents GDB from accessing memory outside the memory map. This
238 is useful for targets with memory mapped registers or which react
239 badly to accesses of unmapped address space.
241 set breakpoint auto-hw
242 show breakpoint auto-hw
243 If the target supplies a memory map, for instance via the remote
244 protocol's "qXfer:memory-map:read" packet, setting this variable
245 lets GDB use hardware breakpoints automatically for memory regions
246 where it can not use software breakpoints. This covers both the
247 "break" command and internal breakpoints used for other commands
248 including "next" and "finish".
251 catch exception unhandled
252 Stop the program execution when Ada exceptions are raised.
255 Stop the program execution when an Ada assertion failed.
259 Set an alternate system root for target files. This is a more
260 general version of "set solib-absolute-prefix", which is now
261 an alias to "set sysroot".
264 Provide extended SPU facility status information. This set of
265 commands is available only when debugging the Cell/B.E. SPU
268 * New native configurations
270 OpenBSD/sh sh*-*openbsd*
275 Use the specified local file as an XML target description, and do
276 not query the target for its built-in description.
280 OpenBSD/sh sh*-*-openbsd*
281 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
282 Toshiba Media Processor mep-elf
287 Ignore the specified signals; pass them directly to the debugged program
288 without stopping other threads or reporting them to GDB.
291 Read an XML target description from the target, which describes its
296 Read or write contents of an spufs file on the target system. These
297 packets are available only on the Cell/B.E. SPU architecture.
299 qXfer:libraries:read:
300 Report the loaded shared libraries. Combined with new "T" packet
301 response, this packet allows GDB to debug shared libraries on
302 targets where the operating system manages the list of loaded
303 libraries (e.g. Windows and SymbianOS).
307 Support for these obsolete configurations has been removed.
316 i[34567]86-*-netware*
317 i[34567]86-*-sco3.2v5*
318 i[34567]86-*-sco3.2v4*
320 i[34567]86-*-sysv4.2*
323 i[34567]86-*-unixware2*
324 i[34567]86-*-unixware*
333 * Other removed features
340 Various m68k-only ROM monitors.
347 Various Renesas ROM monitors and debugging interfaces for SH and
352 Support for a Macraigor serial interface to on-chip debugging.
353 GDB does not directly support the newer parallel or USB
358 A debug information format. The predecessor to DWARF 2 and
359 DWARF 3, which are still supported.
361 Support for the HP aCC compiler on HP-UX/PA-RISC
363 SOM-encapsulated symbolic debugging information, automatic
364 invocation of pxdb, and the aCC custom C++ ABI. This does not
365 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
366 with aCC can still be debugged on an assembly level.
370 A MIPS-specific format used to describe stack frame layout
371 in debugging information.
375 GDB could work with an older version of Guile to debug
376 the interpreter and Scheme programs running in it.
378 set mips stack-arg-size
379 set mips saved-gpreg-size
381 Use "set mips abi" to control parameter passing for MIPS.
383 *** Changes in GDB 6.6
388 Cell Broadband Engine SPU spu-elf
390 * GDB can now be configured as a cross-debugger targeting native Windows
391 (mingw32) or Cygwin. It can communicate with a remote debugging stub
392 running on a Windows system over TCP/IP to debug Windows programs.
394 * The GDB remote stub, gdbserver, has been updated to support Windows and
395 Cygwin debugging. Both single-threaded and multi-threaded programs are
398 * The "set trust-readonly-sections" command works again. This command was
399 broken in GDB 6.3, 6.4, and 6.5.
401 * The "load" command now supports writing to flash memory, if the remote
402 stub provides the required support.
404 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
405 longer requires symbolic debug information (e.g. DWARF-2).
410 unset substitute-path
412 Manage a list of substitution rules that GDB uses to rewrite the name
413 of the directories where the sources are located. This can be useful
414 for instance when the sources were moved to a different location
415 between compilation and debugging.
419 Print each CLI command as it is executed. Each command is prefixed with
420 a number of `+' symbols representing the nesting depth.
421 The source command now has a `-v' option to enable the same feature.
425 The ARM Demon monitor support (RDP protocol, "target rdp").
427 Kernel Object Display, an embedded debugging feature which only worked with
428 an obsolete version of Cisco IOS.
430 The 'set download-write-size' and 'show download-write-size' commands.
435 Tell a stub about GDB client features, and request remote target features.
436 The first feature implemented is PacketSize, which allows the target to
437 specify the size of packets it can handle - to minimize the number of
438 packets required and improve performance when connected to a remote
442 Fetch an OS auxilliary vector from the remote stub. This packet is a
443 more efficient replacement for qPart:auxv:read.
445 qXfer:memory-map:read:
446 Fetch a memory map from the remote stub, including information about
447 RAM, ROM, and flash memory devices.
452 Erase and program a flash memory device.
454 * Removed remote packets
457 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
458 used it, and only gdbserver implemented it.
460 *** Changes in GDB 6.5
464 Renesas M32C/M16C m32c-elf
466 Morpho Technologies ms1 ms1-elf
470 init-if-undefined Initialize a convenience variable, but
471 only if it doesn't already have a value.
473 The following commands are presently only implemented for native GNU/Linux:
475 checkpoint Save a snapshot of the program state.
477 restart <n> Return the program state to a
478 previously saved state.
480 info checkpoints List currently saved checkpoints.
482 delete-checkpoint <n> Delete a previously saved checkpoint.
484 set|show detach-on-fork Tell gdb whether to detach from a newly
485 forked process, or to keep debugging it.
487 info forks List forks of the user program that
488 are available to be debugged.
490 fork <n> Switch to debugging one of several
491 forks of the user program that are
492 available to be debugged.
494 delete-fork <n> Delete a fork from the list of forks
495 that are available to be debugged (and
496 kill the forked process).
498 detach-fork <n> Delete a fork from the list of forks
499 that are available to be debugged (and
500 allow the process to continue).
504 Morpho Technologies ms2 ms1-elf
506 * Improved Windows host support
508 GDB now builds as a cross debugger hosted on i686-mingw32, including
509 native console support, and remote communications using either
510 network sockets or serial ports.
512 * Improved Modula-2 language support
514 GDB can now print most types in the Modula-2 syntax. This includes:
515 basic types, set types, record types, enumerated types, range types,
516 pointer types and ARRAY types. Procedure var parameters are correctly
517 printed and hexadecimal addresses and character constants are also
518 written in the Modula-2 syntax. Best results can be obtained by using
519 GNU Modula-2 together with the -gdwarf-2 command line option.
523 The ARM rdi-share module.
525 The Netware NLM debug server.
527 *** Changes in GDB 6.4
529 * New native configurations
531 OpenBSD/arm arm*-*-openbsd*
532 OpenBSD/mips64 mips64-*-openbsd*
536 Morpho Technologies ms1 ms1-elf
538 * New command line options
540 --batch-silent As for --batch, but totally silent.
541 --return-child-result The debugger will exist with the same value
542 the child (debugged) program exited with.
543 --eval-command COMMAND, -ex COMMAND
544 Execute a single GDB CLI command. This may be
545 specified multiple times and in conjunction
546 with the --command (-x) option.
548 * Deprecated commands removed
550 The following commands, that were deprecated in 2000, have been
554 set|show arm disassembly-flavor set|show arm disassembler
555 othernames set arm disassembler
556 set|show remotedebug set|show debug remote
557 set|show archdebug set|show debug arch
558 set|show eventdebug set|show debug event
561 * New BSD user-level threads support
563 It is now possible to debug programs using the user-level threads
564 library on OpenBSD and FreeBSD. Currently supported (target)
567 FreeBSD/amd64 x86_64-*-freebsd*
568 FreeBSD/i386 i386-*-freebsd*
569 OpenBSD/i386 i386-*-openbsd*
571 Note that the new kernel threads libraries introduced in FreeBSD 5.x
572 are not yet supported.
574 * New support for Matsushita MN10300 w/sim added
575 (Work in progress). mn10300-elf.
577 * REMOVED configurations and files
579 VxWorks and the XDR protocol *-*-vxworks
580 Motorola MCORE mcore-*-*
581 National Semiconductor NS32000 ns32k-*-*
583 * New "set print array-indexes" command
585 After turning this setting "on", GDB prints the index of each element
586 when displaying arrays. The default is "off" to preserve the previous
589 * VAX floating point support
591 GDB now supports the not-quite-ieee VAX F and D floating point formats.
593 * User-defined command support
595 In addition to using $arg0..$arg9 for argument passing, it is now possible
596 to use $argc to determine now many arguments have been passed. See the
597 section on user-defined commands in the user manual for more information.
599 *** Changes in GDB 6.3:
601 * New command line option
603 GDB now accepts -l followed by a number to set the timeout for remote
606 * GDB works with GCC -feliminate-dwarf2-dups
608 GDB now supports a more compact representation of DWARF-2 debug
609 information using DW_FORM_ref_addr references. These are produced
610 by GCC with the option -feliminate-dwarf2-dups and also by some
611 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
612 to use -feliminate-dwarf2-dups.
614 * Internationalization
616 When supported by the host system, GDB will be built with
617 internationalization (libintl). The task of marking up the sources is
618 continued, we're looking forward to our first translation.
622 Initial support for debugging programs compiled with the GNAT
623 implementation of the Ada programming language has been integrated
624 into GDB. In this release, support is limited to expression evaluation.
626 * New native configurations
628 GNU/Linux/m32r m32r-*-linux-gnu
632 GDB's remote protocol now includes support for the 'p' packet. This
633 packet is used to fetch individual registers from a remote inferior.
635 * END-OF-LIFE registers[] compatibility module
637 GDB's internal register infrastructure has been completely rewritten.
638 The new infrastructure making possible the implementation of key new
639 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
642 GDB 6.3 will be the last release to include the the registers[]
643 compatibility module that allowed out-of-date configurations to
644 continue to work. This change directly impacts the following
656 Unless there is activity to revive these configurations, they will be
657 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
659 * OBSOLETE configurations and files
661 Configurations that have been declared obsolete in this release have
662 been commented out. Unless there is activity to revive these
663 configurations, the next release of GDB will have their sources
673 *** Changes in GDB 6.2.1:
675 * MIPS `break main; run' gave an heuristic-fence-post warning
677 When attempting to run even a simple program, a warning about
678 heuristic-fence-post being hit would be reported. This problem has
681 * MIPS IRIX 'long double' crashed GDB
683 When examining a long double variable, GDB would get a segmentation
684 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
685 IRIX long double values).
689 A bug in the VAX stack code was causing problems with the "next"
690 command. This problem has been fixed.
692 *** Changes in GDB 6.2:
694 * Fix for ``many threads''
696 On GNU/Linux systems that use the NPTL threads library, a program
697 rapidly creating and deleting threads would confuse GDB leading to the
700 ptrace: No such process.
701 thread_db_get_info: cannot get thread info: generic error
703 This problem has been fixed.
705 * "-async" and "-noasync" options removed.
707 Support for the broken "-noasync" option has been removed (it caused
710 * New ``start'' command.
712 This command runs the program until the begining of the main procedure.
714 * New BSD Kernel Data Access Library (libkvm) interface
716 Using ``target kvm'' it is now possible to debug kernel core dumps and
717 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
718 platforms. Currently supported (native-only) configurations are:
720 FreeBSD/amd64 x86_64-*-freebsd*
721 FreeBSD/i386 i?86-*-freebsd*
722 NetBSD/i386 i?86-*-netbsd*
723 NetBSD/m68k m68*-*-netbsd*
724 NetBSD/sparc sparc-*-netbsd*
725 OpenBSD/amd64 x86_64-*-openbsd*
726 OpenBSD/i386 i?86-*-openbsd*
727 OpenBSD/m68k m68*-openbsd*
728 OpenBSD/sparc sparc-*-openbsd*
730 * Signal trampoline code overhauled
732 Many generic problems with GDB's signal handling code have been fixed.
733 These include: backtraces through non-contiguous stacks; recognition
734 of sa_sigaction signal trampolines; backtrace from a NULL pointer
735 call; backtrace through a signal trampoline; step into and out of
736 signal handlers; and single-stepping in the signal trampoline.
738 Please note that kernel bugs are a limiting factor here. These
739 features have been shown to work on an s390 GNU/Linux system that
740 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
742 * Cygwin support for DWARF 2 added.
744 * New native configurations
746 GNU/Linux/hppa hppa*-*-linux*
747 OpenBSD/hppa hppa*-*-openbsd*
748 OpenBSD/m68k m68*-*-openbsd*
749 OpenBSD/m88k m88*-*-openbsd*
750 OpenBSD/powerpc powerpc-*-openbsd*
751 NetBSD/vax vax-*-netbsd*
752 OpenBSD/vax vax-*-openbsd*
754 * END-OF-LIFE frame compatibility module
756 GDB's internal frame infrastructure has been completely rewritten.
757 The new infrastructure making it possible to support key new features
758 including DWARF 2 Call Frame Information. To aid in the task of
759 migrating old configurations to this new infrastructure, a
760 compatibility module, that allowed old configurations to continue to
761 work, was also included.
763 GDB 6.2 will be the last release to include this frame compatibility
764 module. This change directly impacts the following configurations:
774 Unless there is activity to revive these configurations, they will be
775 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
777 * REMOVED configurations and files
779 Sun 3, running SunOS 3 m68*-*-sunos3*
780 Sun 3, running SunOS 4 m68*-*-sunos4*
781 Sun 2, running SunOS 3 m68000-*-sunos3*
782 Sun 2, running SunOS 4 m68000-*-sunos4*
783 Motorola 680x0 running LynxOS m68*-*-lynxos*
784 AT&T 3b1/Unix pc m68*-att-*
785 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
786 decstation mips-dec-* mips-little-*
787 riscos mips-*-riscos* mips-*-sysv*
789 sysv mips*-*-sysv4* (IRIX 5/6 not included)
791 *** Changes in GDB 6.1.1:
793 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
795 The TUI (Text-mode User Interface) is now built as part of a default
796 GDB configuration. It is enabled by either selecting the TUI with the
797 command line option "-i=tui" or by running the separate "gdbtui"
798 program. For more information on the TUI, see the manual "Debugging
801 * Pending breakpoint support (also included in GDB 6.1)
803 Support has been added to allow you to specify breakpoints in shared
804 libraries that have not yet been loaded. If a breakpoint location
805 cannot be found, and the "breakpoint pending" option is set to auto,
806 GDB queries you if you wish to make the breakpoint pending on a future
807 shared-library load. If and when GDB resolves the breakpoint symbol,
808 the pending breakpoint is removed as one or more regular breakpoints
811 Pending breakpoints are very useful for GCJ Java debugging.
813 * Fixed ISO-C build problems
815 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
816 non ISO-C code that stopped them being built using a more strict ISO-C
817 compiler (e.g., IBM's C compiler).
819 * Fixed build problem on IRIX 5
821 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
822 wasn't able to compile compile on an IRIX 5 system.
824 * Added execute permission to gdb/gdbserver/configure
826 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
827 permission. This bug would cause configure to fail on a number of
828 systems (Solaris, IRIX). Ref: server/519.
830 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
832 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
833 has been updated to use constant array sizes.
835 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
837 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
838 its generated DWARF Call Frame Info. This encoding was causing GDB to
839 panic, that panic has been fixed. Ref: gdb/1628.
841 * Fixed a problem when examining parameters in shared library code.
843 When examining parameters in optimized shared library code generated
844 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
845 not available''. GDB now correctly displays the variable's value.
847 *** Changes in GDB 6.1:
849 * Removed --with-mmalloc
851 Support for the mmalloc memory manager has been removed, as it
852 conflicted with the internal gdb byte cache.
854 * Changes in AMD64 configurations
856 The AMD64 target now includes the %cs and %ss registers. As a result
857 the AMD64 remote protocol has changed; this affects the floating-point
858 and SSE registers. If you rely on those registers for your debugging,
859 you should upgrade gdbserver on the remote side.
861 * Revised SPARC target
863 The SPARC target has been completely revised, incorporating the
864 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
865 support for LynxOS and SunOS 4 has been dropped. Calling functions
866 from within GDB on operating systems with a non-executable stack
867 (Solaris, OpenBSD) now works.
871 GDB has a new C++ demangler which does a better job on the mangled
872 names generated by current versions of g++. It also runs faster, so
873 with this and other changes gdb should now start faster on large C++
876 * DWARF 2 Location Expressions
878 GDB support for location expressions has been extended to support function
879 arguments and frame bases. Older versions of GDB could crash when they
882 * C++ nested types and namespaces
884 GDB's support for nested types and namespaces in C++ has been
885 improved, especially if you use the DWARF 2 debugging format. (This
886 is the default for recent versions of GCC on most platforms.)
887 Specifically, if you have a class "Inner" defined within a class or
888 namespace "Outer", then GDB realizes that the class's name is
889 "Outer::Inner", not simply "Inner". This should greatly reduce the
890 frequency of complaints about not finding RTTI symbols. In addition,
891 if you are stopped at inside of a function defined within a namespace,
892 GDB modifies its name lookup accordingly.
894 * New native configurations
896 NetBSD/amd64 x86_64-*-netbsd*
897 OpenBSD/amd64 x86_64-*-openbsd*
898 OpenBSD/alpha alpha*-*-openbsd*
899 OpenBSD/sparc sparc-*-openbsd*
900 OpenBSD/sparc64 sparc64-*-openbsd*
902 * New debugging protocols
904 M32R with SDI protocol m32r-*-elf*
906 * "set prompt-escape-char" command deleted.
908 The command "set prompt-escape-char" has been deleted. This command,
909 and its very obscure effet on GDB's prompt, was never documented,
910 tested, nor mentioned in the NEWS file.
912 * OBSOLETE configurations and files
914 Configurations that have been declared obsolete in this release have
915 been commented out. Unless there is activity to revive these
916 configurations, the next release of GDB will have their sources
919 Sun 3, running SunOS 3 m68*-*-sunos3*
920 Sun 3, running SunOS 4 m68*-*-sunos4*
921 Sun 2, running SunOS 3 m68000-*-sunos3*
922 Sun 2, running SunOS 4 m68000-*-sunos4*
923 Motorola 680x0 running LynxOS m68*-*-lynxos*
924 AT&T 3b1/Unix pc m68*-att-*
925 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
926 decstation mips-dec-* mips-little-*
927 riscos mips-*-riscos* mips-*-sysv*
929 sysv mips*-*-sysv4* (IRIX 5/6 not included)
931 * REMOVED configurations and files
933 SGI Irix-4.x mips-sgi-irix4 or iris4
934 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
935 Z8000 simulator z8k-zilog-none or z8ksim
936 Matsushita MN10200 w/simulator mn10200-*-*
937 H8/500 simulator h8500-hitachi-hms or h8500hms
938 HP/PA running BSD hppa*-*-bsd*
939 HP/PA running OSF/1 hppa*-*-osf*
940 HP/PA Pro target hppa*-*-pro*
941 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
942 386BSD i[3456]86-*-bsd*
943 Sequent family i[3456]86-sequent-sysv4*
944 i[3456]86-sequent-sysv*
945 i[3456]86-sequent-bsd*
946 SPARC running LynxOS sparc-*-lynxos*
947 SPARC running SunOS 4 sparc-*-sunos4*
948 Tsqware Sparclet sparclet-*-*
949 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
951 *** Changes in GDB 6.0:
955 Support for debugging the Objective-C programming language has been
958 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
960 DWARF 2's Call Frame Information makes available compiler generated
961 information that more exactly describes the program's run-time stack.
962 By using this information, GDB is able to provide more robust stack
965 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
966 have been updated to use a new backtrace mechanism which includes
971 GDB's remote protocol has been extended to include support for hosted
972 file I/O (where the remote target uses GDB's file system). See GDB's
973 remote protocol documentation for details.
975 * All targets using the new architecture framework.
977 All of GDB's targets have been updated to use the new internal
978 architecture framework. The way is now open for future GDB releases
979 to include cross-architecture native debugging support (i386 on amd64,
982 * GNU/Linux's Thread Local Storage (TLS)
984 GDB now includes support for for the GNU/Linux implementation of
985 per-thread variables.
987 * GNU/Linux's Native POSIX Thread Library (NPTL)
989 GDB's thread code has been updated to work with either the new
990 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
992 * Separate debug info.
994 GDB, in conjunction with BINUTILS, now supports a mechanism for
995 automatically loading debug information from a separate file. Instead
996 of shipping full debug and non-debug versions of system libraries,
997 system integrators can now instead ship just the stripped libraries
998 and optional debug files.
1000 * DWARF 2 Location Expressions
1002 DWARF 2 Location Expressions allow the compiler to more completely
1003 describe the location of variables (even in optimized code) to the
1006 GDB now includes preliminary support for location expressions (support
1007 for DW_OP_piece is still missing).
1011 A number of long standing bugs that caused GDB to die while starting a
1012 Java application have been fixed. GDB's Java support is now
1013 considered "useable".
1015 * GNU/Linux support for fork, vfork, and exec.
1017 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
1018 commands are now implemented for GNU/Linux. They require a 2.5.x or later
1021 * GDB supports logging output to a file
1023 There are two new commands, "set logging" and "show logging", which can be
1024 used to capture GDB's output to a file.
1026 * The meaning of "detach" has changed for gdbserver
1028 The "detach" command will now resume the application, as documented. To
1029 disconnect from gdbserver and leave it stopped, use the new "disconnect"
1032 * d10v, m68hc11 `regs' command deprecated
1034 The `info registers' command has been updated so that it displays the
1035 registers using a format identical to the old `regs' command.
1039 A new command, "maint set profile on/off", has been added. This command can
1040 be used to enable or disable profiling while running GDB, to profile a
1041 session or a set of commands. In addition there is a new configure switch,
1042 "--enable-profiling", which will cause GDB to be compiled with profiling
1043 data, for more informative profiling results.
1045 * Default MI syntax changed to "mi2".
1047 The default MI (machine interface) syntax, enabled by the command line
1048 option "-i=mi", has been changed to "mi2". The previous MI syntax,
1049 "mi1", can be enabled by specifying the option "-i=mi1".
1051 Support for the original "mi0" syntax (included in GDB 5.0) has been
1054 Fix for gdb/192: removed extraneous space when displaying frame level.
1055 Fix for gdb/672: update changelist is now output in mi list format.
1056 Fix for gdb/702: a -var-assign that updates the value now shows up
1057 in a subsequent -var-update.
1059 * New native configurations.
1061 FreeBSD/amd64 x86_64-*-freebsd*
1063 * Multi-arched targets.
1065 HP/PA HPUX11 hppa*-*-hpux*
1066 Renesas M32R/D w/simulator m32r-*-elf*
1068 * OBSOLETE configurations and files
1070 Configurations that have been declared obsolete in this release have
1071 been commented out. Unless there is activity to revive these
1072 configurations, the next release of GDB will have their sources
1073 permanently REMOVED.
1075 Z8000 simulator z8k-zilog-none or z8ksim
1076 Matsushita MN10200 w/simulator mn10200-*-*
1077 H8/500 simulator h8500-hitachi-hms or h8500hms
1078 HP/PA running BSD hppa*-*-bsd*
1079 HP/PA running OSF/1 hppa*-*-osf*
1080 HP/PA Pro target hppa*-*-pro*
1081 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
1082 Sequent family i[3456]86-sequent-sysv4*
1083 i[3456]86-sequent-sysv*
1084 i[3456]86-sequent-bsd*
1085 Tsqware Sparclet sparclet-*-*
1086 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1088 * REMOVED configurations and files
1091 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1092 IBM AIX PS/2 i[3456]86-*-aix
1093 i386 running Mach 3.0 i[3456]86-*-mach3*
1094 i386 running Mach i[3456]86-*-mach*
1095 i386 running OSF/1 i[3456]86-*osf1mk*
1096 HP/Apollo 68k Family m68*-apollo*-sysv*,
1098 m68*-hp-bsd*, m68*-hp-hpux*
1099 Argonaut Risc Chip (ARC) arc-*-*
1100 Mitsubishi D30V d30v-*-*
1101 Fujitsu FR30 fr30-*-elf*
1102 OS/9000 i[34]86-*-os9k
1103 I960 with MON960 i960-*-coff
1105 * MIPS $fp behavior changed
1107 The convenience variable $fp, for the MIPS, now consistently returns
1108 the address of the current frame's base. Previously, depending on the
1109 context, $fp could refer to either $sp or the current frame's base
1110 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
1111 The GNU Source-Level Debugger''.
1113 *** Changes in GDB 5.3:
1115 * GNU/Linux shared library multi-threaded performance improved.
1117 When debugging a multi-threaded application on GNU/Linux, GDB now uses
1118 `/proc', in preference to `ptrace' for memory reads. This may result
1119 in an improvement in the start-up time of multi-threaded, shared
1120 library applications when run under GDB. One GDB user writes: ``loads
1121 shared libs like mad''.
1123 * ``gdbserver'' now supports multi-threaded applications on some targets
1125 Support for debugging multi-threaded applications which use
1126 the GNU/Linux LinuxThreads package has been added for
1127 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
1128 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
1130 * GDB now supports C/C++ preprocessor macros.
1132 GDB now expands preprocessor macro invocations in C/C++ expressions,
1133 and provides various commands for showing macro definitions and how
1136 The new command `macro expand EXPRESSION' expands any macro
1137 invocations in expression, and shows the result.
1139 The new command `show macro MACRO-NAME' shows the definition of the
1140 macro named MACRO-NAME, and where it was defined.
1142 Most compilers don't include information about macros in the debugging
1143 information by default. In GCC 3.1, for example, you need to compile
1144 your program with the options `-gdwarf-2 -g3'. If the macro
1145 information is present in the executable, GDB will read it.
1147 * Multi-arched targets.
1149 DEC Alpha (partial) alpha*-*-*
1150 DEC VAX (partial) vax-*-*
1152 National Semiconductor NS32000 (partial) ns32k-*-*
1153 Motorola 68000 (partial) m68k-*-*
1154 Motorola MCORE mcore-*-*
1158 Fujitsu FRV architecture added by Red Hat frv*-*-*
1161 * New native configurations
1163 Alpha NetBSD alpha*-*-netbsd*
1164 SH NetBSD sh*-*-netbsdelf*
1165 MIPS NetBSD mips*-*-netbsd*
1166 UltraSPARC NetBSD sparc64-*-netbsd*
1168 * OBSOLETE configurations and files
1170 Configurations that have been declared obsolete in this release have
1171 been commented out. Unless there is activity to revive these
1172 configurations, the next release of GDB will have their sources
1173 permanently REMOVED.
1175 Mitsubishi D30V d30v-*-*
1176 OS/9000 i[34]86-*-os9k
1177 IBM AIX PS/2 i[3456]86-*-aix
1178 Fujitsu FR30 fr30-*-elf*
1179 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1180 Argonaut Risc Chip (ARC) arc-*-*
1181 i386 running Mach 3.0 i[3456]86-*-mach3*
1182 i386 running Mach i[3456]86-*-mach*
1183 i386 running OSF/1 i[3456]86-*osf1mk*
1184 HP/Apollo 68k Family m68*-apollo*-sysv*,
1186 m68*-hp-bsd*, m68*-hp-hpux*
1187 I960 with MON960 i960-*-coff
1189 * OBSOLETE languages
1191 CHILL, a Pascal like language used by telecommunications companies.
1193 * REMOVED configurations and files
1195 AMD 29k family via UDI a29k-amd-udi, udi29k
1196 A29K VxWorks a29k-*-vxworks
1197 AMD 29000 embedded, using EBMON a29k-none-none
1198 AMD 29000 embedded with COFF a29k-none-coff
1199 AMD 29000 embedded with a.out a29k-none-aout
1201 testsuite/gdb.hp/gdb.threads-hp/ directory
1203 * New command "set max-user-call-depth <nnn>"
1205 This command allows the user to limit the call depth of user-defined
1206 commands. The default is 1024.
1208 * Changes in FreeBSD/i386 native debugging.
1210 Support for the "generate-core-file" has been added.
1212 * New commands "dump", "append", and "restore".
1214 These commands allow data to be copied from target memory
1215 to a bfd-format or binary file (dump and append), and back
1216 from a file into memory (restore).
1218 * Improved "next/step" support on multi-processor Alpha Tru64.
1220 The previous single-step mechanism could cause unpredictable problems,
1221 including the random appearance of SIGSEGV or SIGTRAP signals. The use
1222 of a software single-step mechanism prevents this.
1224 *** Changes in GDB 5.2.1:
1232 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
1233 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
1234 Fix, by Joel Brobecker imported from mainline.
1236 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
1237 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
1238 Fix, by Fred Fish, imported from mainline.
1240 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
1241 Surprisingly enough, it works now.
1242 By Michal Ludvig, imported from mainline.
1244 i386 hardware watchpoint support:
1245 avoid misses on second run for some targets.
1246 By Pierre Muller, imported from mainline.
1248 *** Changes in GDB 5.2:
1250 * New command "set trust-readonly-sections on[off]".
1252 This command is a hint that tells gdb that read-only sections
1253 really are read-only (ie. that their contents will not change).
1254 In this mode, gdb will go to the object file rather than the
1255 target to read memory from read-only sections (such as ".text").
1256 This can be a significant performance improvement on some
1257 (notably embedded) targets.
1259 * New command "generate-core-file" (or "gcore").
1261 This new gdb command allows the user to drop a core file of the child
1262 process state at any time. So far it's been implemented only for
1263 GNU/Linux and Solaris, but should be relatively easily ported to other
1264 hosts. Argument is core file name (defaults to core.<pid>).
1266 * New command line option
1268 GDB now accepts --pid or -p followed by a process id.
1270 * Change in command line behavior -- corefiles vs. process ids.
1272 There is a subtle behavior in the way in which GDB handles
1273 command line arguments. The first non-flag argument is always
1274 a program to debug, but the second non-flag argument may either
1275 be a corefile or a process id. Previously, GDB would attempt to
1276 open the second argument as a corefile, and if that failed, would
1277 issue a superfluous error message and then attempt to attach it as
1278 a process. Now, if the second argument begins with a non-digit,
1279 it will be treated as a corefile. If it begins with a digit,
1280 GDB will attempt to attach it as a process, and if no such process
1281 is found, will then attempt to open it as a corefile.
1283 * Changes in ARM configurations.
1285 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
1286 configuration is fully multi-arch.
1288 * New native configurations
1290 ARM NetBSD arm*-*-netbsd*
1291 x86 OpenBSD i[3456]86-*-openbsd*
1292 AMD x86-64 running GNU/Linux x86_64-*-linux-*
1293 Sparc64 running FreeBSD sparc64-*-freebsd*
1297 Sanyo XStormy16 xstormy16-elf
1299 * OBSOLETE configurations and files
1301 Configurations that have been declared obsolete in this release have
1302 been commented out. Unless there is activity to revive these
1303 configurations, the next release of GDB will have their sources
1304 permanently REMOVED.
1306 AMD 29k family via UDI a29k-amd-udi, udi29k
1307 A29K VxWorks a29k-*-vxworks
1308 AMD 29000 embedded, using EBMON a29k-none-none
1309 AMD 29000 embedded with COFF a29k-none-coff
1310 AMD 29000 embedded with a.out a29k-none-aout
1312 testsuite/gdb.hp/gdb.threads-hp/ directory
1314 * REMOVED configurations and files
1316 TI TMS320C80 tic80-*-*
1318 PowerPC Solaris powerpcle-*-solaris*
1319 PowerPC Windows NT powerpcle-*-cygwin32
1320 PowerPC Netware powerpc-*-netware*
1321 Harris/CXUX m88k m88*-harris-cxux*
1322 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1323 ns32k-utek-sysv* ns32k-utek-*
1324 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1325 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1326 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1327 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1328 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
1330 * Changes to command line processing
1332 The new `--args' feature can be used to specify command-line arguments
1333 for the inferior from gdb's command line.
1335 * Changes to key bindings
1337 There is a new `operate-and-get-next' function bound to `C-o'.
1339 *** Changes in GDB 5.1.1
1341 Fix compile problem on DJGPP.
1343 Fix a problem with floating-point registers on the i386 being
1346 Fix to stop GDB crashing on .debug_str debug info.
1348 Numerous documentation fixes.
1350 Numerous testsuite fixes.
1352 *** Changes in GDB 5.1:
1354 * New native configurations
1356 Alpha FreeBSD alpha*-*-freebsd*
1357 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
1358 MIPS GNU/Linux mips*-*-linux*
1359 MIPS SGI Irix 6.x mips*-sgi-irix6*
1360 ia64 AIX ia64-*-aix*
1361 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
1365 Motorola 68HC11 and 68HC12 m68hc11-elf
1367 UltraSparc running GNU/Linux sparc64-*-linux*
1369 * OBSOLETE configurations and files
1371 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
1372 Harris/CXUX m88k m88*-harris-cxux*
1373 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
1374 ns32k-utek-sysv* ns32k-utek-*
1375 TI TMS320C80 tic80-*-*
1377 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
1378 PowerPC Solaris powerpcle-*-solaris*
1379 PowerPC Windows NT powerpcle-*-cygwin32
1380 PowerPC Netware powerpc-*-netware*
1381 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
1382 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
1383 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
1384 Apple Macintosh (MPW) host N/A
1386 stuff.c (Program to stuff files into a specially prepared space in kdb)
1387 kdb-start.c (Main loop for the standalone kernel debugger)
1389 Configurations that have been declared obsolete in this release have
1390 been commented out. Unless there is activity to revive these
1391 configurations, the next release of GDB will have their sources
1392 permanently REMOVED.
1394 * REMOVED configurations and files
1396 Altos 3068 m68*-altos-*
1397 Convex c1-*-*, c2-*-*
1399 ARM RISCix arm-*-* (as host)
1403 * GDB has been converted to ISO C.
1405 GDB's source code has been converted to ISO C. In particular, the
1406 sources are fully protoized, and rely on standard headers being
1411 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
1413 * The MI enabled by default.
1415 The new machine oriented interface (MI) introduced in GDB 5.0 has been
1416 revised and enabled by default. Packages which use GDB as a debugging
1417 engine behind a UI or another front end are encouraged to switch to
1418 using the GDB/MI interface, instead of the old annotations interface
1419 which is now deprecated.
1421 * Support for debugging Pascal programs.
1423 GDB now includes support for debugging Pascal programs. The following
1424 main features are supported:
1426 - Pascal-specific data types such as sets;
1428 - automatic recognition of Pascal sources based on file-name
1431 - Pascal-style display of data types, variables, and functions;
1433 - a Pascal expression parser.
1435 However, some important features are not yet supported.
1437 - Pascal string operations are not supported at all;
1439 - there are some problems with boolean types;
1441 - Pascal type hexadecimal constants are not supported
1442 because they conflict with the internal variables format;
1444 - support for Pascal objects and classes is not full yet;
1446 - unlike Pascal, GDB is case-sensitive for symbol names.
1448 * Changes in completion.
1450 Commands such as `shell', `run' and `set args', which pass arguments
1451 to inferior programs, now complete on file names, similar to what
1452 users expect at the shell prompt.
1454 Commands which accept locations, such as `disassemble', `print',
1455 `breakpoint', `until', etc. now complete on filenames as well as
1456 program symbols. Thus, if you type "break foob TAB", and the source
1457 files linked into the programs include `foobar.c', that file name will
1458 be one of the candidates for completion. However, file names are not
1459 considered for completion after you typed a colon that delimits a file
1460 name from a name of a function in that file, as in "break foo.c:bar".
1462 `set demangle-style' completes on available demangling styles.
1464 * New platform-independent commands:
1466 It is now possible to define a post-hook for a command as well as a
1467 hook that runs before the command. For more details, see the
1468 documentation of `hookpost' in the GDB manual.
1470 * Changes in GNU/Linux native debugging.
1472 Support for debugging multi-threaded programs has been completely
1473 revised for all platforms except m68k and sparc. You can now debug as
1474 many threads as your system allows you to have.
1476 Attach/detach is supported for multi-threaded programs.
1478 Support for SSE registers was added for x86. This doesn't work for
1479 multi-threaded programs though.
1481 * Changes in MIPS configurations.
1483 Multi-arch support is enabled for all MIPS configurations.
1485 GDB can now be built as native debugger on SGI Irix 6.x systems for
1486 debugging n32 executables. (Debugging 64-bit executables is not yet
1489 * Unified support for hardware watchpoints in all x86 configurations.
1491 Most (if not all) native x86 configurations support hardware-assisted
1492 breakpoints and watchpoints in a unified manner. This support
1493 implements debug register sharing between watchpoints, which allows to
1494 put a virtually infinite number of watchpoints on the same address,
1495 and also supports watching regions up to 16 bytes with several debug
1498 The new maintenance command `maintenance show-debug-regs' toggles
1499 debugging print-outs in functions that insert, remove, and test
1500 watchpoints and hardware breakpoints.
1502 * Changes in the DJGPP native configuration.
1504 New command ``info dos sysinfo'' displays assorted information about
1505 the CPU, OS, memory, and DPMI server.
1507 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
1508 display information about segment descriptors stored in GDT, LDT, and
1511 New commands ``info dos pde'' and ``info dos pte'' display entries
1512 from Page Directory and Page Tables (for now works with CWSDPMI only).
1513 New command ``info dos address-pte'' displays the Page Table entry for
1514 a given linear address.
1516 GDB can now pass command lines longer than 126 characters to the
1517 program being debugged (requires an update to the libdbg.a library
1518 which is part of the DJGPP development kit).
1520 DWARF2 debug info is now supported.
1522 It is now possible to `step' and `next' through calls to `longjmp'.
1524 * Changes in documentation.
1526 All GDB documentation was converted to GFDL, the GNU Free
1527 Documentation License.
1529 Tracepoints-related commands are now fully documented in the GDB
1532 TUI, the Text-mode User Interface, is now documented in the manual.
1534 Tracepoints-related commands are now fully documented in the GDB
1537 The "GDB Internals" manual now has an index. It also includes
1538 documentation of `ui_out' functions, GDB coding standards, x86
1539 hardware watchpoints, and memory region attributes.
1541 * GDB's version number moved to ``version.in''
1543 The Makefile variable VERSION has been replaced by the file
1544 ``version.in''. People creating GDB distributions should update the
1545 contents of this file.
1549 GUD support is now a standard part of the EMACS distribution.
1551 *** Changes in GDB 5.0:
1553 * Improved support for debugging FP programs on x86 targets
1555 Unified and much-improved support for debugging floating-point
1556 programs on all x86 targets. In particular, ``info float'' now
1557 displays the FP registers in the same format on all x86 targets, with
1558 greater level of detail.
1560 * Improvements and bugfixes in hardware-assisted watchpoints
1562 It is now possible to watch array elements, struct members, and
1563 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1564 on x86 targets no longer erroneously trigger when the address is
1567 * Improvements in the native DJGPP version of GDB
1569 The distribution now includes all the scripts and auxiliary files
1570 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1571 machines ``out of the box''.
1573 The DJGPP version can now debug programs that use signals. It is
1574 possible to catch signals that happened in the debuggee, deliver
1575 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1576 would kill the program being debugged.) Programs that hook hardware
1577 interrupts (keyboard, timer, etc.) can also be debugged.
1579 It is now possible to debug DJGPP programs that redirect their
1580 standard handles or switch them to raw (as opposed to cooked) mode, or
1581 even close them. The command ``run < foo > bar'' works as expected,
1582 and ``info terminal'' reports useful information about the debuggee's
1583 terminal, including raw/cooked mode, redirection, etc.
1585 The DJGPP version now uses termios functions for console I/O, which
1586 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1589 DOS-style file names with drive letters are now fully supported by
1592 It is now possible to debug DJGPP programs that switch their working
1593 directory. It is also possible to rerun the debuggee any number of
1594 times without restarting GDB; thus, you can use the same setup,
1595 breakpoints, etc. for many debugging sessions.
1597 * New native configurations
1599 ARM GNU/Linux arm*-*-linux*
1600 PowerPC GNU/Linux powerpc-*-linux*
1604 Motorola MCore mcore-*-*
1605 x86 VxWorks i[3456]86-*-vxworks*
1606 PowerPC VxWorks powerpc-*-vxworks*
1607 TI TMS320C80 tic80-*-*
1609 * OBSOLETE configurations
1611 Altos 3068 m68*-altos-*
1612 Convex c1-*-*, c2-*-*
1614 ARM RISCix arm-*-* (as host)
1617 Configurations that have been declared obsolete will be commented out,
1618 but the code will be left in place. If there is no activity to revive
1619 these configurations before the next release of GDB, the sources will
1620 be permanently REMOVED.
1622 * Gould support removed
1624 Support for the Gould PowerNode and NP1 has been removed.
1626 * New features for SVR4
1628 On SVR4 native platforms (such as Solaris), if you attach to a process
1629 without first loading a symbol file, GDB will now attempt to locate and
1630 load symbols from the running process's executable file.
1632 * Many C++ enhancements
1634 C++ support has been greatly improved. Overload resolution now works properly
1635 in almost all cases. RTTI support is on the way.
1637 * Remote targets can connect to a sub-program
1639 A popen(3) style serial-device has been added. This device starts a
1640 sub-process (such as a stand-alone simulator) and then communicates
1641 with that. The sub-program to run is specified using the syntax
1642 ``|<program> <args>'' vis:
1644 (gdb) set remotedebug 1
1645 (gdb) target extended-remote |mn10300-elf-sim program-args
1647 * MIPS 64 remote protocol
1649 A long standing bug in the mips64 remote protocol where by GDB
1650 expected certain 32 bit registers (ex SR) to be transfered as 32
1651 instead of 64 bits has been fixed.
1653 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1654 added to provide backward compatibility with older versions of GDB.
1656 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1658 The command ``set remotebinarydownload'' command has been replaced by
1659 ``set remote X-packet''. Other commands in ``set remote'' family
1660 include ``set remote P-packet''.
1662 * Breakpoint commands accept ranges.
1664 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1665 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1666 ``tracepoint passcount'' also accepts a range of tracepoints.
1668 * ``apropos'' command added.
1670 The ``apropos'' command searches through command names and
1671 documentation strings, printing out matches, making it much easier to
1672 try to find a command that does what you are looking for.
1676 A new machine oriented interface (MI) has been added to GDB. This
1677 interface is designed for debug environments running GDB as a separate
1678 process. This is part of the long term libGDB project. See the
1679 "GDB/MI" chapter of the GDB manual for further information. It can be
1680 enabled by configuring with:
1682 .../configure --enable-gdbmi
1684 *** Changes in GDB-4.18:
1686 * New native configurations
1688 HP-UX 10.20 hppa*-*-hpux10.20
1689 HP-UX 11.x hppa*-*-hpux11.0*
1690 M68K GNU/Linux m68*-*-linux*
1694 Fujitsu FR30 fr30-*-elf*
1695 Intel StrongARM strongarm-*-*
1696 Mitsubishi D30V d30v-*-*
1698 * OBSOLETE configurations
1700 Gould PowerNode, NP1 np1-*-*, pn-*-*
1702 Configurations that have been declared obsolete will be commented out,
1703 but the code will be left in place. If there is no activity to revive
1704 these configurations before the next release of GDB, the sources will
1705 be permanently REMOVED.
1709 As a compatibility experiment, GDB's source files buildsym.h and
1710 buildsym.c have been converted to pure standard C, no longer
1711 containing any K&R compatibility code. We believe that all systems in
1712 use today either come with a standard C compiler, or have a GCC port
1713 available. If this is not true, please report the affected
1714 configuration to bug-gdb@gnu.org immediately. See the README file for
1715 information about getting a standard C compiler if you don't have one
1720 GDB now uses readline 2.2.
1722 * set extension-language
1724 You can now control the mapping between filename extensions and source
1725 languages by using the `set extension-language' command. For instance,
1726 you can ask GDB to treat .c files as C++ by saying
1727 set extension-language .c c++
1728 The command `info extensions' lists all of the recognized extensions
1729 and their associated languages.
1731 * Setting processor type for PowerPC and RS/6000
1733 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1734 you can use the `set processor' command to specify what variant of the
1735 PowerPC family you are debugging. The command
1739 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
1740 following PowerPC and RS6000 variants:
1742 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
1743 rs6000 IBM RS6000 ("POWER") architecture, user-level view
1745 403GC IBM PowerPC 403GC
1746 505 Motorola PowerPC 505
1747 860 Motorola PowerPC 860 or 850
1748 601 Motorola PowerPC 601
1749 602 Motorola PowerPC 602
1750 603 Motorola/IBM PowerPC 603 or 603e
1751 604 Motorola PowerPC 604 or 604e
1752 750 Motorola/IBM PowerPC 750 or 750
1754 At the moment, this command just tells GDB what to name the
1755 special-purpose processor registers. Since almost all the affected
1756 registers are inaccessible to user-level programs, this command is
1757 only useful for remote debugging in its present form.
1761 Thanks to a major code donation from Hewlett-Packard, GDB now has much
1762 more extensive support for HP-UX. Added features include shared
1763 library support, kernel threads and hardware watchpoints for 11.00,
1764 support for HP's ANSI C and C++ compilers, and a compatibility mode
1765 for xdb and dbx commands.
1769 HP's donation includes the new concept of catchpoints, which is a
1770 generalization of the old catch command. On HP-UX, it is now possible
1771 to catch exec, fork, and vfork, as well as library loading.
1773 This means that the existing catch command has changed; its first
1774 argument now specifies the type of catch to be set up. See the
1775 output of "help catch" for a list of catchpoint types.
1777 * Debugging across forks
1779 On HP-UX, you can choose which process to debug when a fork() happens
1784 HP has donated a curses-based terminal user interface (TUI). To get
1785 it, build with --enable-tui. Although this can be enabled for any
1786 configuration, at present it only works for native HP debugging.
1788 * GDB remote protocol additions
1790 A new protocol packet 'X' that writes binary data is now available.
1791 Default behavior is to try 'X', then drop back to 'M' if the stub
1792 fails to respond. The settable variable `remotebinarydownload'
1793 allows explicit control over the use of 'X'.
1795 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1796 full 64-bit address. The command
1798 set remoteaddresssize 32
1800 can be used to revert to the old behaviour. For existing remote stubs
1801 the change should not be noticed, as the additional address information
1804 In order to assist in debugging stubs, you may use the maintenance
1805 command `packet' to send any text string to the stub. For instance,
1807 maint packet heythere
1809 sends the packet "$heythere#<checksum>". Note that it is very easy to
1810 disrupt a debugging session by sending the wrong packet at the wrong
1813 The compare-sections command allows you to compare section data on the
1814 target to what is in the executable file without uploading or
1815 downloading, by comparing CRC checksums.
1817 * Tracing can collect general expressions
1819 You may now collect general expressions at tracepoints. This requires
1820 further additions to the target-side stub; see tracepoint.c and
1821 doc/agentexpr.texi for further details.
1823 * mask-address variable for Mips
1825 For Mips targets, you may control the zeroing of the upper 32 bits of
1826 a 64-bit address by entering `set mask-address on'. This is mainly
1827 of interest to users of embedded R4xxx and R5xxx processors.
1829 * Higher serial baud rates
1831 GDB's serial code now allows you to specify baud rates 57600, 115200,
1832 230400, and 460800 baud. (Note that your host system may not be able
1833 to achieve all of these rates.)
1837 The i960 configuration now includes an initial implementation of a
1838 builtin simulator, contributed by Jim Wilson.
1841 *** Changes in GDB-4.17:
1843 * New native configurations
1845 Alpha GNU/Linux alpha*-*-linux*
1846 Unixware 2.x i[3456]86-unixware2*
1847 Irix 6.x mips*-sgi-irix6*
1848 PowerPC GNU/Linux powerpc-*-linux*
1849 PowerPC Solaris powerpcle-*-solaris*
1850 Sparc GNU/Linux sparc-*-linux*
1851 Motorola sysV68 R3V7.1 m68k-motorola-sysv
1855 Argonaut Risc Chip (ARC) arc-*-*
1856 Hitachi H8/300S h8300*-*-*
1857 Matsushita MN10200 w/simulator mn10200-*-*
1858 Matsushita MN10300 w/simulator mn10300-*-*
1859 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1860 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1861 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1862 Mitsubishi D10V w/simulator d10v-*-*
1863 Mitsubishi M32R/D w/simulator m32r-*-elf*
1864 Tsqware Sparclet sparclet-*-*
1865 NEC V850 w/simulator v850-*-*
1867 * New debugging protocols
1869 ARM with RDI protocol arm*-*-*
1870 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1871 DDB and LSI variants of PMON protocol mips*-*-*
1872 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1873 PowerPC with SDS protocol powerpc{,le}-*-eabi
1874 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1878 All configurations can now understand and use the DWARF 2 debugging
1879 format. The choice is automatic, if the symbol file contains DWARF 2
1884 GDB now includes basic Java language support. This support is
1885 only useful with Java compilers that produce native machine code.
1887 * solib-absolute-prefix and solib-search-path
1889 For SunOS and SVR4 shared libraries, you may now set the prefix for
1890 loading absolute shared library symbol files, and the search path for
1891 locating non-absolute shared library symbol files.
1893 * Live range splitting
1895 GDB can now effectively debug code for which GCC has performed live
1896 range splitting as part of its optimization. See gdb/doc/LRS for
1897 more details on the expected format of the stabs information.
1901 GDB's support for the GNU Hurd, including thread debugging, has been
1902 updated to work with current versions of the Hurd.
1906 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1907 instruction set. ARM GDB automatically detects when Thumb
1908 instructions are in use, and adjusts disassembly and backtracing
1913 GDB's MIPS target configurations now handle the MIP16 16-bit
1918 GDB now includes support for overlays; if an executable has been
1919 linked such that multiple sections are based at the same address, GDB
1920 will decide which section to use for symbolic info. You can choose to
1921 control the decision manually, using overlay commands, or implement
1922 additional target-side support and use "overlay load-target" to bring
1923 in the overlay mapping. Do "help overlay" for more detail.
1927 The command "info symbol <address>" displays information about
1928 the symbol at the specified address.
1932 The standard remote protocol now includes an extension that allows
1933 asynchronous collection and display of trace data. This requires
1934 extensive support in the target-side debugging stub. Tracing mode
1935 includes a new interaction mode in GDB and new commands: see the
1936 file tracepoint.c for more details.
1940 Configurations for embedded MIPS now include a simulator contributed
1941 by Cygnus Solutions. The simulator supports the instruction sets
1942 of most MIPS variants.
1946 Sparc configurations may now include the ERC32 simulator contributed
1947 by the European Space Agency. The simulator is not built into
1948 Sparc targets by default; configure with --enable-sim to include it.
1952 For target configurations that may include multiple variants of a
1953 basic architecture (such as MIPS and SH), you may now set the
1954 architecture explicitly. "set arch" sets, "info arch" lists
1955 the possible architectures.
1957 *** Changes in GDB-4.16:
1959 * New native configurations
1961 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1962 M68K NetBSD m68k-*-netbsd*
1963 PowerPC AIX 4.x powerpc-*-aix*
1964 PowerPC MacOS powerpc-*-macos*
1965 PowerPC Windows NT powerpcle-*-cygwin32
1966 RS/6000 AIX 4.x rs6000-*-aix4*
1970 ARM with RDP protocol arm-*-*
1971 I960 with MON960 i960-*-coff
1972 MIPS VxWorks mips*-*-vxworks*
1973 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1974 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1976 Matra Sparclet sparclet-*-*
1980 The powerpc-eabi configuration now includes the PSIM simulator,
1981 contributed by Andrew Cagney, with assistance from Mike Meissner.
1982 PSIM is a very elaborate model of the PowerPC, including not only
1983 basic instruction set execution, but also details of execution unit
1984 performance and I/O hardware. See sim/ppc/README for more details.
1988 GDB now works with Solaris 2.5.
1990 * Windows 95/NT native
1992 GDB will now work as a native debugger on Windows 95 and Windows NT.
1993 To build it from source, you must use the "gnu-win32" environment,
1994 which uses a DLL to emulate enough of Unix to run the GNU tools.
1995 Further information, binaries, and sources are available at
1996 ftp.cygnus.com, under pub/gnu-win32.
1998 * dont-repeat command
2000 If a user-defined command includes the command `dont-repeat', then the
2001 command will not be repeated if the user just types return. This is
2002 useful if the command is time-consuming to run, so that accidental
2003 extra keystrokes don't run the same command many times.
2005 * Send break instead of ^C
2007 The standard remote protocol now includes an option to send a break
2008 rather than a ^C to the target in order to interrupt it. By default,
2009 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
2011 * Remote protocol timeout
2013 The standard remote protocol includes a new variable `remotetimeout'
2014 that allows you to set the number of seconds before GDB gives up trying
2015 to read from the target. The default value is 2.
2017 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
2019 By default GDB will automatically keep track of objects as they are
2020 loaded and unloaded by the dynamic linker. By using the command `set
2021 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
2022 when shared library events occur, thus allowing you to set breakpoints
2023 in shared libraries which are explicitly loaded by the inferior.
2025 Note this feature does not work on hpux8. On hpux9 you must link
2026 /usr/lib/end.o into your program. This feature should work
2027 automatically on hpux10.
2029 * Irix 5.x hardware watchpoint support
2031 Irix 5 configurations now support the use of hardware watchpoints.
2033 * Mips protocol "SYN garbage limit"
2035 When debugging a Mips target using the `target mips' protocol, you
2036 may set the number of characters that GDB will ignore by setting
2037 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
2038 every character. The default value is 1050.
2040 * Recording and replaying remote debug sessions
2042 If you set `remotelogfile' to the name of a file, gdb will write to it
2043 a recording of a remote debug session. This recording may then be
2044 replayed back to gdb using "gdbreplay". See gdbserver/README for
2045 details. This is useful when you have a problem with GDB while doing
2046 remote debugging; you can make a recording of the session and send it
2047 to someone else, who can then recreate the problem.
2049 * Speedups for remote debugging
2051 GDB includes speedups for downloading and stepping MIPS systems using
2052 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
2053 and more efficient S-record downloading.
2055 * Memory use reductions and statistics collection
2057 GDB now uses less memory and reports statistics about memory usage.
2058 Try the `maint print statistics' command, for example.
2060 *** Changes in GDB-4.15:
2062 * Psymtabs for XCOFF
2064 The symbol reader for AIX GDB now uses partial symbol tables. This
2065 can greatly improve startup time, especially for large executables.
2067 * Remote targets use caching
2069 Remote targets now use a data cache to speed up communication with the
2070 remote side. The data cache could lead to incorrect results because
2071 it doesn't know about volatile variables, thus making it impossible to
2072 debug targets which use memory mapped I/O devices. `set remotecache
2073 off' turns the the data cache off.
2075 * Remote targets may have threads
2077 The standard remote protocol now includes support for multiple threads
2078 in the target system, using new protocol commands 'H' and 'T'. See
2079 gdb/remote.c for details.
2083 If GDB is configured with `--enable-netrom', then it will include
2084 support for the NetROM ROM emulator from XLNT Designs. The NetROM
2085 acts as though it is a bank of ROM on the target board, but you can
2086 write into it over the network. GDB's support consists only of
2087 support for fast loading into the emulated ROM; to debug, you must use
2088 another protocol, such as standard remote protocol. The usual
2089 sequence is something like
2091 target nrom <netrom-hostname>
2093 target remote <netrom-hostname>:1235
2097 GDB now includes support for the Apple Macintosh, as a host only. It
2098 may be run as either an MPW tool or as a standalone application, and
2099 it can debug through the serial port. All the usual GDB commands are
2100 available, but to the target command, you must supply "serial" as the
2101 device type instead of "/dev/ttyXX". See mpw-README in the main
2102 directory for more information on how to build. The MPW configuration
2103 scripts */mpw-config.in support only a few targets, and only the
2104 mips-idt-ecoff target has been tested.
2108 GDB configuration now uses autoconf. This is not user-visible,
2109 but does simplify configuration and building.
2113 GDB now supports hpux10.
2115 *** Changes in GDB-4.14:
2117 * New native configurations
2119 x86 FreeBSD i[345]86-*-freebsd
2120 x86 NetBSD i[345]86-*-netbsd
2121 NS32k NetBSD ns32k-*-netbsd
2122 Sparc NetBSD sparc-*-netbsd
2126 A29K VxWorks a29k-*-vxworks
2127 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
2128 CPU32 EST-300 emulator m68*-*-est*
2129 PowerPC ELF powerpc-*-elf
2132 * Alpha OSF/1 support for procfs
2134 GDB now supports procfs under OSF/1-2.x and higher, which makes it
2135 possible to attach to running processes. As the mounting of the /proc
2136 filesystem is optional on the Alpha, GDB automatically determines
2137 the availability of /proc during startup. This can lead to problems
2138 if /proc is unmounted after GDB has been started.
2140 * Arguments to user-defined commands
2142 User commands may accept up to 10 arguments separated by whitespace.
2143 Arguments are accessed within the user command via $arg0..$arg9. A
2146 print $arg0 + $arg1 + $arg2
2148 To execute the command use:
2151 Defines the command "adder" which prints the sum of its three arguments.
2152 Note the arguments are text substitutions, so they may reference variables,
2153 use complex expressions, or even perform inferior function calls.
2155 * New `if' and `while' commands
2157 This makes it possible to write more sophisticated user-defined
2158 commands. Both commands take a single argument, which is the
2159 expression to evaluate, and must be followed by the commands to
2160 execute, one per line, if the expression is nonzero, the list being
2161 terminated by the word `end'. The `if' command list may include an
2162 `else' word, which causes the following commands to be executed only
2163 if the expression is zero.
2165 * Fortran source language mode
2167 GDB now includes partial support for Fortran 77. It will recognize
2168 Fortran programs and can evaluate a subset of Fortran expressions, but
2169 variables and functions may not be handled correctly. GDB will work
2170 with G77, but does not yet know much about symbols emitted by other
2173 * Better HPUX support
2175 Most debugging facilities now work on dynamic executables for HPPAs
2176 running hpux9 or later. You can attach to running dynamically linked
2177 processes, but by default the dynamic libraries will be read-only, so
2178 for instance you won't be able to put breakpoints in them. To change
2179 that behavior do the following before running the program:
2185 This will cause the libraries to be mapped private and read-write.
2186 To revert to the normal behavior, do this:
2192 You cannot set breakpoints or examine data in the library until after
2193 the library is loaded if the function/data symbols do not have
2196 GDB can now also read debug symbols produced by the HP C compiler on
2197 HPPAs (sorry, no C++, Fortran or 68k support).
2199 * Target byte order now dynamically selectable
2201 You can choose which byte order to use with a target system, via the
2202 commands "set endian big" and "set endian little", and you can see the
2203 current setting by using "show endian". You can also give the command
2204 "set endian auto", in which case GDB will use the byte order
2205 associated with the executable. Currently, only embedded MIPS
2206 configurations support dynamic selection of target byte order.
2208 * New DOS host serial code
2210 This version uses DPMI interrupts to handle buffered I/O, so you
2211 no longer need to run asynctsr when debugging boards connected to
2214 *** Changes in GDB-4.13:
2216 * New "complete" command
2218 This lists all the possible completions for the rest of the line, if it
2219 were to be given as a command itself. This is intended for use by emacs.
2221 * Trailing space optional in prompt
2223 "set prompt" no longer adds a space for you after the prompt you set. This
2224 allows you to set a prompt which ends in a space or one that does not.
2226 * Breakpoint hit counts
2228 "info break" now displays a count of the number of times the breakpoint
2229 has been hit. This is especially useful in conjunction with "ignore"; you
2230 can ignore a large number of breakpoint hits, look at the breakpoint info
2231 to see how many times the breakpoint was hit, then run again, ignoring one
2232 less than that number, and this will get you quickly to the last hit of
2235 * Ability to stop printing at NULL character
2237 "set print null-stop" will cause GDB to stop printing the characters of
2238 an array when the first NULL is encountered. This is useful when large
2239 arrays actually contain only short strings.
2241 * Shared library breakpoints
2243 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
2244 breakpoints in shared libraries before the executable is run.
2246 * Hardware watchpoints
2248 There is a new hardware breakpoint for the watch command for sparclite
2249 targets. See gdb/sparclite/hw_breakpoint.note.
2251 Hardware watchpoints are also now supported under GNU/Linux.
2255 Annotations have been added. These are for use with graphical interfaces,
2256 and are still experimental. Currently only gdba.el uses these.
2258 * Improved Irix 5 support
2260 GDB now works properly with Irix 5.2.
2262 * Improved HPPA support
2264 GDB now works properly with the latest GCC and GAS.
2266 * New native configurations
2268 Sequent PTX4 i[34]86-sequent-ptx4
2269 HPPA running OSF/1 hppa*-*-osf*
2270 Atari TT running SVR4 m68*-*-sysv4*
2271 RS/6000 LynxOS rs6000-*-lynxos*
2275 OS/9000 i[34]86-*-os9k
2276 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
2279 * Hitachi SH7000 and E7000-PC ICE support
2281 There is now support for communicating with the Hitachi E7000-PC ICE.
2282 This is available automatically when GDB is configured for the SH.
2286 As usual, a variety of small fixes and improvements, both generic
2287 and configuration-specific. See the ChangeLog for more detail.
2289 *** Changes in GDB-4.12:
2291 * Irix 5 is now supported
2295 GDB-4.12 on the HPPA has a number of changes which make it unable
2296 to debug the output from the currently released versions of GCC and
2297 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
2298 of GCC and GAS, versions of these tools designed to work with GDB-4.12
2299 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
2302 *** Changes in GDB-4.11:
2304 * User visible changes:
2308 The "set remotedebug" option is now consistent between the mips remote
2309 target, remote targets using the gdb-specific protocol, UDI (AMD's
2310 debug protocol for the 29k) and the 88k bug monitor. It is now an
2311 integer specifying a debug level (normally 0 or 1, but 2 means more
2312 debugging info for the mips target).
2314 * DEC Alpha native support
2316 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
2317 debug info, but GDB works fairly well with the DEC compiler and should
2318 work with a future GCC release. See the README file for a few
2319 Alpha-specific notes.
2321 * Preliminary thread implementation
2323 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
2325 * LynxOS native and target support for 386
2327 This release has been hosted on LynxOS 2.2, and also can be configured
2328 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
2331 * Improvements in C++ mangling/demangling.
2333 This release has much better g++ debugging, specifically in name
2334 mangling/demangling, virtual function calls, print virtual table,
2335 call methods, ...etc.
2337 *** Changes in GDB-4.10:
2339 * User visible changes:
2341 Remote debugging using the GDB-specific (`target remote') protocol now
2342 supports the `load' command. This is only useful if you have some
2343 other way of getting the stub to the target system, and you can put it
2344 somewhere in memory where it won't get clobbered by the download.
2346 Filename completion now works.
2348 When run under emacs mode, the "info line" command now causes the
2349 arrow to point to the line specified. Also, "info line" prints
2350 addresses in symbolic form (as well as hex).
2352 All vxworks based targets now support a user settable option, called
2353 vxworks-timeout. This option represents the number of seconds gdb
2354 should wait for responses to rpc's. You might want to use this if
2355 your vxworks target is, perhaps, a slow software simulator or happens
2356 to be on the far side of a thin network line.
2360 This release contains support for using a DEC alpha as a GDB host for
2361 cross debugging. Native alpha debugging is not supported yet.
2364 *** Changes in GDB-4.9:
2368 This is the first GDB release which is accompanied by a matching testsuite.
2369 The testsuite requires installation of dejagnu, which should be available
2370 via ftp from most sites that carry GNU software.
2374 'Cfront' style demangling has had its name changed to 'ARM' style, to
2375 emphasize that it was written from the specifications in the C++ Annotated
2376 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
2377 disclaimers, it still generated too much confusion with users attempting to
2378 use gdb with AT&T cfront.
2382 GDB now uses a standard remote interface to a simulator library.
2383 So far, the library contains simulators for the Zilog Z8001/2, the
2384 Hitachi H8/300, H8/500 and Super-H.
2386 * New targets supported
2388 H8/300 simulator h8300-hitachi-hms or h8300hms
2389 H8/500 simulator h8500-hitachi-hms or h8500hms
2390 SH simulator sh-hitachi-hms or sh
2391 Z8000 simulator z8k-zilog-none or z8ksim
2392 IDT MIPS board over serial line mips-idt-ecoff
2394 Cross-debugging to GO32 targets is supported. It requires a custom
2395 version of the i386-stub.c module which is integrated with the
2396 GO32 memory extender.
2398 * New remote protocols
2400 MIPS remote debugging protocol.
2402 * New source languages supported
2404 This version includes preliminary support for Chill, a Pascal like language
2405 used by telecommunications companies. Chill support is also being integrated
2406 into the GNU compiler, but we don't know when it will be publically available.
2409 *** Changes in GDB-4.8:
2411 * HP Precision Architecture supported
2413 GDB now supports HP PA-RISC machines running HPUX. A preliminary
2414 version of this support was available as a set of patches from the
2415 University of Utah. GDB does not support debugging of programs
2416 compiled with the HP compiler, because HP will not document their file
2417 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
2418 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
2420 Many problems in the preliminary version have been fixed.
2422 * Faster and better demangling
2424 We have improved template demangling and fixed numerous bugs in the GNU style
2425 demangler. It can now handle type modifiers such as `static' or `const'. Wide
2426 character types (wchar_t) are now supported. Demangling of each symbol is now
2427 only done once, and is cached when the symbol table for a file is read in.
2428 This results in a small increase in memory usage for C programs, a moderate
2429 increase in memory usage for C++ programs, and a fantastic speedup in
2432 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
2433 from the specifications in the Annotated Reference Manual, which AT&T's
2434 compiler does not actually implement.
2436 * G++ multiple inheritance compiler problem
2438 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
2439 inheritance lattices was reworked to properly discover ambiguities. We
2440 recently found an example which causes this new algorithm to fail in a
2441 very subtle way, producing bad debug information for those classes.
2442 The file 'gcc.patch' (in this directory) can be applied to gcc to
2443 circumvent the problem. A future GCC release will contain a complete
2446 The previous G++ debug info problem (mentioned below for the gdb-4.7
2447 release) is fixed in gcc version 2.3.2.
2449 * Improved configure script
2451 The `configure' script will now attempt to guess your system type if
2452 you don't supply a host system type. The old scheme of supplying a
2453 host system triplet is preferable over using this. All the magic is
2454 done in the new `config.guess' script. Examine it for details.
2456 We have also brought our configure script much more in line with the FSF's
2457 version. It now supports the --with-xxx options. In particular,
2458 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
2459 The resulting GDB will not be able to read arbitrary object file formats --
2460 only the format ``expected'' to be used on the configured target system.
2461 We hope to make this the default in a future release.
2463 * Documentation improvements
2465 There's new internal documentation on how to modify GDB, and how to
2466 produce clean changes to the code. We implore people to read it
2467 before submitting changes.
2469 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
2470 M4 macros. The new texinfo.tex is provided in this release. Pre-built
2471 `info' files are also provided. To build `info' files from scratch,
2472 you will need the latest `makeinfo' release, which will be available in
2473 a future texinfo-X.Y release.
2475 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
2476 We're not sure exactly which versions have this problem, but it has
2477 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
2478 or better. If that isn't possible, there is a patch in
2479 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
2480 around this problem.
2484 GDB now supports array constants that can be used in expressions typed in by
2485 the user. The syntax is `{element, element, ...}'. Ie: you can now type
2486 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
2489 The new directory `gdb/sparclite' contains a program that demonstrates
2490 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
2492 * New native hosts supported
2494 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
2495 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
2497 * New targets supported
2499 AMD 29k family via UDI a29k-amd-udi or udi29k
2501 * New file formats supported
2503 BFD now supports reading HP/PA-RISC executables (SOM file format?),
2504 HPUX core files, and SCO 3.2v2 core files.
2508 Attaching to processes now works again; thanks for the many bug reports.
2510 We have also stomped on a bunch of core dumps caused by
2511 printf_filtered("%s") problems.
2513 We eliminated a copyright problem on the rpc and ptrace header files
2514 for VxWorks, which was discovered at the last minute during the 4.7
2515 release. You should now be able to build a VxWorks GDB.
2517 You can now interrupt gdb while an attached process is running. This
2518 will cause the attached process to stop, and give control back to GDB.
2520 We fixed problems caused by using too many file descriptors
2521 for reading symbols from object files and libraries. This was
2522 especially a problem for programs that used many (~100) shared
2525 The `step' command now only enters a subroutine if there is line number
2526 information for the subroutine. Otherwise it acts like the `next'
2527 command. Previously, `step' would enter subroutines if there was
2528 any debugging information about the routine. This avoids problems
2529 when using `cc -g1' on MIPS machines.
2531 * Internal improvements
2533 GDB's internal interfaces have been improved to make it easier to support
2534 debugging of multiple languages in the future.
2536 GDB now uses a common structure for symbol information internally.
2537 Minimal symbols (derived from linkage symbols in object files), partial
2538 symbols (from a quick scan of debug information), and full symbols
2539 contain a common subset of information, making it easier to write
2540 shared code that handles any of them.
2542 * New command line options
2544 We now accept --silent as an alias for --quiet.
2548 The memory-mapped-malloc library is now licensed under the GNU Library
2549 General Public License.
2551 *** Changes in GDB-4.7:
2553 * Host/native/target split
2555 GDB has had some major internal surgery to untangle the support for
2556 hosts and remote targets. Now, when you configure GDB for a remote
2557 target, it will no longer load in all of the support for debugging
2558 local programs on the host. When fully completed and tested, this will
2559 ensure that arbitrary host/target combinations are possible.
2561 The primary conceptual shift is to separate the non-portable code in
2562 GDB into three categories. Host specific code is required any time GDB
2563 is compiled on that host, regardless of the target. Target specific
2564 code relates to the peculiarities of the target, but can be compiled on
2565 any host. Native specific code is everything else: it can only be
2566 built when the host and target are the same system. Child process
2567 handling and core file support are two common `native' examples.
2569 GDB's use of /proc for controlling Unix child processes is now cleaner.
2570 It has been split out into a single module under the `target_ops' vector,
2571 plus two native-dependent functions for each system that uses /proc.
2573 * New hosts supported
2575 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2576 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2577 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2579 * New targets supported
2581 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2582 68030 and CPU32 m68030-*-*, m68332-*-*
2584 * New native hosts supported
2586 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2587 (386bsd is not well tested yet)
2588 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2590 * New file formats supported
2592 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2593 supports reading of `a.out.adobe' object files, which are an a.out
2594 format extended with minimal information about multiple sections.
2598 `show copying' is the same as the old `info copying'.
2599 `show warranty' is the same as `info warrantee'.
2600 These were renamed for consistency. The old commands continue to work.
2602 `info handle' is a new alias for `info signals'.
2604 You can now define pre-command hooks, which attach arbitrary command
2605 scripts to any command. The commands in the hook will be executed
2606 prior to the user's command. You can also create a hook which will be
2607 executed whenever the program stops. See gdb.texinfo.
2611 We now deal with Cfront style name mangling, and can even extract type
2612 info from mangled symbols. GDB can automatically figure out which
2613 symbol mangling style your C++ compiler uses.
2615 Calling of methods and virtual functions has been improved as well.
2619 The crash that occured when debugging Sun Ansi-C compiled binaries is
2620 fixed. This was due to mishandling of the extra N_SO stabs output
2623 We also finally got Ultrix 4.2 running in house, and fixed core file
2624 support, with help from a dozen people on the net.
2626 John M. Farrell discovered that the reason that single-stepping was so
2627 slow on all of the Mips based platforms (primarily SGI and DEC) was
2628 that we were trying to demangle and lookup a symbol used for internal
2629 purposes on every instruction that was being stepped through. Changing
2630 the name of that symbol so that it couldn't be mistaken for a C++
2631 mangled symbol sped things up a great deal.
2633 Rich Pixley sped up symbol lookups in general by getting much smarter
2634 about when C++ symbol mangling is necessary. This should make symbol
2635 completion (TAB on the command line) much faster. It's not as fast as
2636 we'd like, but it's significantly faster than gdb-4.6.
2640 A new user controllable variable 'call_scratch_address' can
2641 specify the location of a scratch area to be used when GDB
2642 calls a function in the target. This is necessary because the
2643 usual method of putting the scratch area on the stack does not work
2644 in systems that have separate instruction and data spaces.
2646 We integrated changes to support the 29k UDI (Universal Debugger
2647 Interface), but discovered at the last minute that we didn't have all
2648 of the appropriate copyright paperwork. We are working with AMD to
2649 resolve this, and hope to have it available soon.
2653 We have sped up the remote serial line protocol, especially for targets
2654 with lots of registers. It now supports a new `expedited status' ('T')
2655 message which can be used in place of the existing 'S' status message.
2656 This allows the remote stub to send only the registers that GDB
2657 needs to make a quick decision about single-stepping or conditional
2658 breakpoints, eliminating the need to fetch the entire register set for
2659 each instruction being stepped through.
2661 The GDB remote serial protocol now implements a write-through cache for
2662 registers, only re-reading the registers if the target has run.
2664 There is also a new remote serial stub for SPARC processors. You can
2665 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2666 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2667 processor with a serial port.
2671 Configure.in files have become much easier to read and modify. A new
2672 `table driven' format makes it more obvious what configurations are
2673 supported, and what files each one uses.
2677 There is a new opcodes library which will eventually contain all of the
2678 disassembly routines and opcode tables. At present, it only contains
2679 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2680 disassembler (binutils/objdump) to share these routines.
2682 The libiberty library is now copylefted under the GNU Library General
2683 Public License. This allows more liberal use, and was done so libg++
2684 can use it. This makes no difference to GDB, since the Library License
2685 grants all the rights from the General Public License.
2689 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2690 reference to the stabs symbol info used by the debugger. It is (as far
2691 as we know) the only published document on this fascinating topic. We
2692 encourage you to read it, compare it to the stabs information on your
2693 system, and send improvements on the document in general (to
2694 bug-gdb@prep.ai.mit.edu).
2696 And, of course, many bugs have been fixed.
2699 *** Changes in GDB-4.6:
2701 * Better support for C++ function names
2703 GDB now accepts as input the "demangled form" of C++ overloaded function
2704 names and member function names, and can do command completion on such names
2705 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2706 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2707 Make use of command completion, it is your friend.
2709 GDB also now accepts a variety of C++ mangled symbol formats. They are
2710 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2711 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2712 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2713 for the list of formats.
2715 * G++ symbol mangling problem
2717 Recent versions of gcc have a bug in how they emit debugging information for
2718 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2719 directory) can be applied to gcc to fix the problem. Alternatively, if you
2720 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2721 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2722 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2725 * New 'maintenance' command
2727 All of the commands related to hacking GDB internals have been moved out of
2728 the main command set, and now live behind the 'maintenance' command. This
2729 can also be abbreviated as 'mt'. The following changes were made:
2731 dump-me -> maintenance dump-me
2732 info all-breakpoints -> maintenance info breakpoints
2733 printmsyms -> maintenance print msyms
2734 printobjfiles -> maintenance print objfiles
2735 printpsyms -> maintenance print psymbols
2736 printsyms -> maintenance print symbols
2738 The following commands are new:
2740 maintenance demangle Call internal GDB demangler routine to
2741 demangle a C++ link name and prints the result.
2742 maintenance print type Print a type chain for a given symbol
2744 * Change to .gdbinit file processing
2746 We now read the $HOME/.gdbinit file before processing the argv arguments
2747 (e.g. reading symbol files or core files). This allows global parameters to
2748 be set, which will apply during the symbol reading. The ./.gdbinit is still
2749 read after argv processing.
2751 * New hosts supported
2753 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
2755 GNU/Linux support i386-unknown-linux or linux
2757 We are also including code to support the HP/PA running BSD and HPUX. This
2758 is almost guaranteed not to work, as we didn't have time to test or build it
2759 for this release. We are including it so that the more adventurous (or
2760 masochistic) of you can play with it. We also had major problems with the
2761 fact that the compiler that we got from HP doesn't support the -g option.
2764 * New targets supported
2766 Hitachi H8/300 h8300-hitachi-hms or h8300hms
2768 * More smarts about finding #include files
2770 GDB now remembers the compilation directory for all include files, and for
2771 all files from which C is generated (like yacc and lex sources). This
2772 greatly improves GDB's ability to find yacc/lex sources, and include files,
2773 especially if you are debugging your program from a directory different from
2774 the one that contains your sources.
2776 We also fixed a bug which caused difficulty with listing and setting
2777 breakpoints in include files which contain C code. (In the past, you had to
2778 try twice in order to list an include file that you hadn't looked at before.)
2780 * Interesting infernals change
2782 GDB now deals with arbitrary numbers of sections, where the symbols for each
2783 section must be relocated relative to that section's landing place in the
2784 target's address space. This work was needed to support ELF with embedded
2785 stabs used by Solaris-2.0.
2787 * Bug fixes (of course!)
2789 There have been loads of fixes for the following things:
2790 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2791 i960, stabs, DOS(GO32), procfs, etc...
2793 See the ChangeLog for details.
2795 *** Changes in GDB-4.5:
2797 * New machines supported (host and target)
2799 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2801 SGI Irix-4.x mips-sgi-irix4 or iris4
2803 * New malloc package
2805 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2806 Mmalloc is capable of handling mutiple heaps of memory. It is also
2807 capable of saving a heap to a file, and then mapping it back in later.
2808 This can be used to greatly speedup the startup of GDB by using a
2809 pre-parsed symbol table which lives in a mmalloc managed heap. For
2810 more details, please read mmalloc/mmalloc.texi.
2814 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2815 'help info proc' for details.
2817 * MIPS ecoff symbol table format
2819 The code that reads MIPS symbol table format is now supported on all hosts.
2820 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2823 * File name changes for MS-DOS
2825 Many files in the config directories have been renamed to make it easier to
2826 support GDB on MS-DOSe systems (which have very restrictive file name
2827 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2828 environment) is close to working but has some remaining problems. Note
2829 that debugging of DOS programs is not supported, due to limitations
2830 in the ``operating system'', but it can be used to host cross-debugging.
2832 * Cross byte order fixes
2834 Many fixes have been made to support cross debugging of Sparc and MIPS
2835 targets from hosts whose byte order differs.
2837 * New -mapped and -readnow options
2839 If memory-mapped files are available on your system through the 'mmap'
2840 system call, you can use the -mapped option on the `file' or
2841 `symbol-file' commands to cause GDB to write the symbols from your
2842 program into a reusable file. If the program you are debugging is
2843 called `/path/fred', the mapped symbol file will be `./fred.syms'.
2844 Future GDB debugging sessions will notice the presence of this file,
2845 and will quickly map in symbol information from it, rather than reading
2846 the symbol table from the executable program. Using the '-mapped'
2847 option in a GDB `file' or `symbol-file' command has the same effect as
2848 starting GDB with the '-mapped' command-line option.
2850 You can cause GDB to read the entire symbol table immediately by using
2851 the '-readnow' option with any of the commands that load symbol table
2852 information (or on the GDB command line). This makes the command
2853 slower, but makes future operations faster.
2855 The -mapped and -readnow options are typically combined in order to
2856 build a `fred.syms' file that contains complete symbol information.
2857 A simple GDB invocation to do nothing but build a `.syms' file for future
2860 gdb -batch -nx -mapped -readnow programname
2862 The `.syms' file is specific to the host machine on which GDB is run.
2863 It holds an exact image of GDB's internal symbol table. It cannot be
2864 shared across multiple host platforms.
2866 * longjmp() handling
2868 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2869 siglongjmp() without losing control. This feature has not yet been ported to
2870 all systems. It currently works on many 386 platforms, all MIPS-based
2871 platforms (SGI, DECstation, etc), and Sun3/4.
2875 Preliminary work has been put in to support the new Solaris OS from Sun. At
2876 this time, it can control and debug processes, but it is not capable of
2881 As always, many many bug fixes. The major areas were with g++, and mipsread.
2882 People using the MIPS-based platforms should experience fewer mysterious
2883 crashes and trashed symbol tables.
2885 *** Changes in GDB-4.4:
2887 * New machines supported (host and target)
2889 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2891 BSD Reno on Vax vax-dec-bsd
2892 Ultrix on Vax vax-dec-ultrix
2894 * New machines supported (target)
2896 AMD 29000 embedded, using EBMON a29k-none-none
2900 GDB continues to improve its handling of C++. `References' work better.
2901 The demangler has also been improved, and now deals with symbols mangled as
2902 per the Annotated C++ Reference Guide.
2904 GDB also now handles `stabs' symbol information embedded in MIPS
2905 `ecoff' symbol tables. Since the ecoff format was not easily
2906 extensible to handle new languages such as C++, this appeared to be a
2907 good way to put C++ debugging info into MIPS binaries. This option
2908 will be supported in the GNU C compiler, version 2, when it is
2911 * New features for SVR4
2913 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2914 shared libraries. Debugging dynamically linked programs should present
2915 only minor differences from debugging statically linked programs.
2917 The `info proc' command will print out information about any process
2918 on an SVR4 system (including the one you are debugging). At the moment,
2919 it prints the address mappings of the process.
2921 If you bring up GDB on another SVR4 system, please send mail to
2922 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2924 * Better dynamic linking support in SunOS
2926 Reading symbols from shared libraries which contain debugging symbols
2927 now works properly. However, there remain issues such as automatic
2928 skipping of `transfer vector' code during function calls, which
2929 make it harder to debug code in a shared library, than to debug the
2930 same code linked statically.
2934 GDB is now using the latest `getopt' routines from the FSF. This
2935 version accepts the -- prefix for options with long names. GDB will
2936 continue to accept the old forms (-option and +option) as well.
2937 Various single letter abbreviations for options have been explicity
2938 added to the option table so that they won't get overshadowed in the
2939 future by other options that begin with the same letter.
2943 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2944 Many assorted bugs have been handled. Many more remain to be handled.
2945 See the various ChangeLog files (primarily in gdb and bfd) for details.
2948 *** Changes in GDB-4.3:
2950 * New machines supported (host and target)
2952 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2953 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2954 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2956 * Almost SCO Unix support
2958 We had hoped to support:
2959 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2960 (except for core file support), but we discovered very late in the release
2961 that it has problems with process groups that render gdb unusable. Sorry
2962 about that. I encourage people to fix it and post the fixes.
2964 * Preliminary ELF and DWARF support
2966 GDB can read ELF object files on System V Release 4, and can handle
2967 debugging records for C, in DWARF format, in ELF files. This support
2968 is preliminary. If you bring up GDB on another SVR4 system, please
2969 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2974 GDB now uses the latest `readline' library. One user-visible change
2975 is that two tabs will list possible command completions, which previously
2976 required typing M-? (meta-question mark, or ESC ?).
2980 The `stepi' bug that many of you noticed has been squashed.
2981 Many bugs in C++ have been handled. Many more remain to be handled.
2982 See the various ChangeLog files (primarily in gdb and bfd) for details.
2984 * State of the MIPS world (in case you wondered):
2986 GDB can understand the symbol tables emitted by the compilers
2987 supplied by most vendors of MIPS-based machines, including DEC. These
2988 symbol tables are in a format that essentially nobody else uses.
2990 Some versions of gcc come with an assembler post-processor called
2991 mips-tfile. This program is required if you want to do source-level
2992 debugging of gcc-compiled programs. I believe FSF does not ship
2993 mips-tfile with gcc version 1, but it will eventually come with gcc
2996 Debugging of g++ output remains a problem. g++ version 1.xx does not
2997 really support it at all. (If you're lucky, you should be able to get
2998 line numbers and stack traces to work, but no parameters or local
2999 variables.) With some work it should be possible to improve the
3002 When gcc version 2 is released, you will have somewhat better luck.
3003 However, even then you will get confusing results for inheritance and
3006 We will eventually provide full debugging of g++ output on
3007 DECstations. This will probably involve some kind of stabs-in-ecoff
3008 encapulation, but the details have not been worked out yet.
3011 *** Changes in GDB-4.2:
3013 * Improved configuration
3015 Only one copy of `configure' exists now, and it is not self-modifying.
3016 Porting BFD is simpler.
3020 The `step' and `next' commands now only stop at the first instruction
3021 of a source line. This prevents the multiple stops that used to occur
3022 in switch statements, for-loops, etc. `Step' continues to stop if a
3023 function that has debugging information is called within the line.
3027 Lots of small bugs fixed. More remain.
3029 * New host supported (not target)
3031 Intel 386 PC clone running Mach i386-none-mach
3034 *** Changes in GDB-4.1:
3036 * Multiple source language support
3038 GDB now has internal scaffolding to handle several source languages.
3039 It determines the type of each source file from its filename extension,
3040 and will switch expression parsing and number formatting to match the
3041 language of the function in the currently selected stack frame.
3042 You can also specifically set the language to be used, with
3043 `set language c' or `set language modula-2'.
3047 GDB now has preliminary support for the GNU Modula-2 compiler,
3048 currently under development at the State University of New York at
3049 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
3050 continue through the fall of 1991 and into 1992.
3052 Other Modula-2 compilers are currently not supported, and attempting to
3053 debug programs compiled with them will likely result in an error as the
3054 symbol table is read. Feel free to work on it, though!
3056 There are hooks in GDB for strict type checking and range checking,
3057 in the `Modula-2 philosophy', but they do not currently work.
3061 GDB can now write to executable and core files (e.g. patch
3062 a variable's value). You must turn this switch on, specify
3063 the file ("exec foo" or "core foo"), *then* modify it, e.g.
3064 by assigning a new value to a variable. Modifications take
3067 * Automatic SunOS shared library reading
3069 When you run your program, GDB automatically determines where its
3070 shared libraries (if any) have been loaded, and reads their symbols.
3071 The `share' command is no longer needed. This also works when
3072 examining core files.
3076 You can specify the number of lines that the `list' command shows.
3079 * New machines supported (host and target)
3081 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
3082 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
3083 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
3085 * New hosts supported (not targets)
3087 IBM RT/PC: romp-ibm-aix or rtpc
3089 * New targets supported (not hosts)
3091 AMD 29000 embedded with COFF a29k-none-coff
3092 AMD 29000 embedded with a.out a29k-none-aout
3093 Ultracomputer remote kernel debug a29k-nyu-kern
3095 * New remote interfaces
3101 *** Changes in GDB-4.0:
3105 Wide output is wrapped at good places to make the output more readable.
3107 Gdb now supports cross-debugging from a host machine of one type to a
3108 target machine of another type. Communication with the target system
3109 is over serial lines. The ``target'' command handles connecting to the
3110 remote system; the ``load'' command will download a program into the
3111 remote system. Serial stubs for the m68k and i386 are provided. Gdb
3112 also supports debugging of realtime processes running under VxWorks,
3113 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
3114 stub on the target system.
3116 New CPUs supported include the AMD 29000 and Intel 960.
3118 GDB now reads object files and symbol tables via a ``binary file''
3119 library, which allows a single copy of GDB to debug programs of multiple
3120 object file types such as a.out and coff.
3122 There is now a GDB reference card in "doc/refcard.tex". (Make targets
3123 refcard.dvi and refcard.ps are available to format it).
3126 * Control-Variable user interface simplified
3128 All variables that control the operation of the debugger can be set
3129 by the ``set'' command, and displayed by the ``show'' command.
3131 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
3132 ``Show prompt'' produces the response:
3133 Gdb's prompt is new-gdb=>.
3135 What follows are the NEW set commands. The command ``help set'' will
3136 print a complete list of old and new set commands. ``help set FOO''
3137 will give a longer description of the variable FOO. ``show'' will show
3138 all of the variable descriptions and their current settings.
3140 confirm on/off: Enables warning questions for operations that are
3141 hard to recover from, e.g. rerunning the program while
3142 it is already running. Default is ON.
3144 editing on/off: Enables EMACS style command line editing
3145 of input. Previous lines can be recalled with
3146 control-P, the current line can be edited with control-B,
3147 you can search for commands with control-R, etc.
3150 history filename NAME: NAME is where the gdb command history
3151 will be stored. The default is .gdb_history,
3152 or the value of the environment variable
3155 history size N: The size, in commands, of the command history. The
3156 default is 256, or the value of the environment variable
3159 history save on/off: If this value is set to ON, the history file will
3160 be saved after exiting gdb. If set to OFF, the
3161 file will not be saved. The default is OFF.
3163 history expansion on/off: If this value is set to ON, then csh-like
3164 history expansion will be performed on
3165 command line input. The default is OFF.
3167 radix N: Sets the default radix for input and output. It can be set
3168 to 8, 10, or 16. Note that the argument to "radix" is interpreted
3169 in the current radix, so "set radix 10" is always a no-op.
3171 height N: This integer value is the number of lines on a page. Default
3172 is 24, the current `stty rows'' setting, or the ``li#''
3173 setting from the termcap entry matching the environment
3176 width N: This integer value is the number of characters on a line.
3177 Default is 80, the current `stty cols'' setting, or the ``co#''
3178 setting from the termcap entry matching the environment
3181 Note: ``set screensize'' is obsolete. Use ``set height'' and
3182 ``set width'' instead.
3184 print address on/off: Print memory addresses in various command displays,
3185 such as stack traces and structure values. Gdb looks
3186 more ``symbolic'' if you turn this off; it looks more
3187 ``machine level'' with it on. Default is ON.
3189 print array on/off: Prettyprint arrays. New convenient format! Default
3192 print demangle on/off: Print C++ symbols in "source" form if on,
3195 print asm-demangle on/off: Same, for assembler level printouts
3198 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
3201 * Support for Epoch Environment.
3203 The epoch environment is a version of Emacs v18 with windowing. One
3204 new command, ``inspect'', is identical to ``print'', except that if you
3205 are running in the epoch environment, the value is printed in its own
3209 * Support for Shared Libraries
3211 GDB can now debug programs and core files that use SunOS shared libraries.
3212 Symbols from a shared library cannot be referenced
3213 before the shared library has been linked with the program (this
3214 happens after you type ``run'' and before the function main() is entered).
3215 At any time after this linking (including when examining core files
3216 from dynamically linked programs), gdb reads the symbols from each
3217 shared library when you type the ``sharedlibrary'' command.
3218 It can be abbreviated ``share''.
3220 sharedlibrary REGEXP: Load shared object library symbols for files
3221 matching a unix regular expression. No argument
3222 indicates to load symbols for all shared libraries.
3224 info sharedlibrary: Status of loaded shared libraries.
3229 A watchpoint stops execution of a program whenever the value of an
3230 expression changes. Checking for this slows down execution
3231 tremendously whenever you are in the scope of the expression, but is
3232 quite useful for catching tough ``bit-spreader'' or pointer misuse
3233 problems. Some machines such as the 386 have hardware for doing this
3234 more quickly, and future versions of gdb will use this hardware.
3236 watch EXP: Set a watchpoint (breakpoint) for an expression.
3238 info watchpoints: Information about your watchpoints.
3240 delete N: Deletes watchpoint number N (same as breakpoints).
3241 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
3242 enable N: Re-enables watchpoint number N (same as breakpoints).
3245 * C++ multiple inheritance
3247 When used with a GCC version 2 compiler, GDB supports multiple inheritance
3250 * C++ exception handling
3252 Gdb now supports limited C++ exception handling. Besides the existing
3253 ability to breakpoint on an exception handler, gdb can breakpoint on
3254 the raising of an exception (before the stack is peeled back to the
3257 catch FOO: If there is a FOO exception handler in the dynamic scope,
3258 set a breakpoint to catch exceptions which may be raised there.
3259 Multiple exceptions (``catch foo bar baz'') may be caught.
3261 info catch: Lists all exceptions which may be caught in the
3262 current stack frame.
3265 * Minor command changes
3267 The command ``call func (arg, arg, ...)'' now acts like the print
3268 command, except it does not print or save a value if the function's result
3269 is void. This is similar to dbx usage.
3271 The ``up'' and ``down'' commands now always print the frame they end up
3272 at; ``up-silently'' and `down-silently'' can be used in scripts to change
3273 frames without printing.
3275 * New directory command
3277 'dir' now adds directories to the FRONT of the source search path.
3278 The path starts off empty. Source files that contain debug information
3279 about the directory in which they were compiled can be found even
3280 with an empty path; Sun CC and GCC include this information. If GDB can't
3281 find your source file in the current directory, type "dir .".
3283 * Configuring GDB for compilation
3285 For normal use, type ``./configure host''. See README or gdb.texinfo
3288 GDB now handles cross debugging. If you are remotely debugging between
3289 two different machines, type ``./configure host -target=targ''.
3290 Host is the machine where GDB will run; targ is the machine
3291 where the program that you are debugging will run.