1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.3
6 * New native configurations
8 OpenBSD/arm arm*-*-openbsd*
9 OpenBSD/mips64 mips64-*-openbsd*
13 Morpho Technologies ms1 ms1-elf
15 * New command line options
17 --batch-silent As for --batch, but totally silent.
18 --return-child-result The debugger will exist with the same value
19 the child (debugged) program exited with.
20 --eval-command COMMAND, -ex COMMAND
21 Execute a single GDB CLI command. This may be
22 specified multiple times and in conjunction
23 with the --command (-x) option.
25 * Deprecated commands removed
27 The following commands, that were deprecated in 2000, have been
31 set|show arm disassembly-flavor set|show arm disassembler
32 othernames set arm disassembler
33 set|show remotedebug set|show debug remote
34 set|show archdebug set|show debug arch
35 set|show eventdebug set|show debug event
38 * New BSD user-level threads support
40 It is now possible to debug programs using the user-level threads
41 library on OpenBSD and FreeBSD. Currently supported (target)
44 FreeBSD/amd64 x86_64-*-freebsd*
45 FreeBSD/i386 i386-*-freebsd*
46 OpenBSD/i386 i386-*-openbsd*
48 Note that the new kernel threads libraries introduced in FreeBSD 5.x
49 are not yet supported.
51 * New support for Matsushita MN10300 w/sim added
52 (Work in progress). mn10300-elf.
54 * REMOVED configurations and files
56 VxWorks and the XDR protocol *-*-vxworks
57 Renesas H8/300S h8300*-*-*
58 Motorola MCORE mcore-*-*
59 Matsushita MN10300 w/simulator mn10300-*-*
60 National Semiconductor NS32000 ns32k-*-*
63 * New "set print array-indexes" command
65 After turning this setting "on", GDB prints the index of each element
66 when displaying arrays. The default is "off" to preserve the previous
69 * VAX floating point support
71 GDB now supports the not-quite-ieee VAX F and D floating point formats.
73 *** Changes in GDB 6.3:
75 * New command line option
77 GDB now accepts -l followed by a number to set the timeout for remote
80 * GDB works with GCC -feliminate-dwarf2-dups
82 GDB now supports a more compact representation of DWARF-2 debug
83 information using DW_FORM_ref_addr references. These are produced
84 by GCC with the option -feliminate-dwarf2-dups and also by some
85 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
86 to use -feliminate-dwarf2-dups.
88 * Internationalization
90 When supported by the host system, GDB will be built with
91 internationalization (libintl). The task of marking up the sources is
92 continued, we're looking forward to our first translation.
96 Initial support for debugging programs compiled with the GNAT
97 implementation of the Ada programming language has been integrated
98 into GDB. In this release, support is limited to expression evaluation.
100 * New native configurations
102 GNU/Linux/m32r m32r-*-linux-gnu
106 GDB's remote protocol now includes support for the 'p' packet. This
107 packet is used to fetch individual registers from a remote inferior.
109 * END-OF-LIFE registers[] compatibility module
111 GDB's internal register infrastructure has been completely rewritten.
112 The new infrastructure making possible the implementation of key new
113 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
116 GDB 6.3 will be the last release to include the the registers[]
117 compatibility module that allowed out-of-date configurations to
118 continue to work. This change directly impacts the following
130 Unless there is activity to revive these configurations, they will be
131 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
133 * OBSOLETE configurations and files
135 Configurations that have been declared obsolete in this release have
136 been commented out. Unless there is activity to revive these
137 configurations, the next release of GDB will have their sources
147 *** Changes in GDB 6.2.1:
149 * MIPS `break main; run' gave an heuristic-fence-post warning
151 When attempting to run even a simple program, a warning about
152 heuristic-fence-post being hit would be reported. This problem has
155 * MIPS IRIX 'long double' crashed GDB
157 When examining a long double variable, GDB would get a segmentation
158 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
159 IRIX long double values).
163 A bug in the VAX stack code was causing problems with the "next"
164 command. This problem has been fixed.
166 *** Changes in GDB 6.2:
168 * Fix for ``many threads''
170 On GNU/Linux systems that use the NPTL threads library, a program
171 rapidly creating and deleting threads would confuse GDB leading to the
174 ptrace: No such process.
175 thread_db_get_info: cannot get thread info: generic error
177 This problem has been fixed.
179 * "-async" and "-noasync" options removed.
181 Support for the broken "-noasync" option has been removed (it caused
184 * New ``start'' command.
186 This command runs the program until the begining of the main procedure.
188 * New BSD Kernel Data Access Library (libkvm) interface
190 Using ``target kvm'' it is now possible to debug kernel core dumps and
191 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
192 platforms. Currently supported (native-only) configurations are:
194 FreeBSD/amd64 x86_64-*-freebsd*
195 FreeBSD/i386 i?86-*-freebsd*
196 NetBSD/i386 i?86-*-netbsd*
197 NetBSD/m68k m68*-*-netbsd*
198 NetBSD/sparc sparc-*-netbsd*
199 OpenBSD/amd64 x86_64-*-openbsd*
200 OpenBSD/i386 i?86-*-openbsd*
201 OpenBSD/m68k m68*-openbsd*
202 OpenBSD/sparc sparc-*-openbsd*
204 * Signal trampoline code overhauled
206 Many generic problems with GDB's signal handling code have been fixed.
207 These include: backtraces through non-contiguous stacks; recognition
208 of sa_sigaction signal trampolines; backtrace from a NULL pointer
209 call; backtrace through a signal trampoline; step into and out of
210 signal handlers; and single-stepping in the signal trampoline.
212 Please note that kernel bugs are a limiting factor here. These
213 features have been shown to work on an s390 GNU/Linux system that
214 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
216 * Cygwin support for DWARF 2 added.
218 * New native configurations
220 GNU/Linux/hppa hppa*-*-linux*
221 OpenBSD/hppa hppa*-*-openbsd*
222 OpenBSD/m68k m68*-*-openbsd*
223 OpenBSD/m88k m88*-*-openbsd*
224 OpenBSD/powerpc powerpc-*-openbsd*
225 NetBSD/vax vax-*-netbsd*
226 OpenBSD/vax vax-*-openbsd*
228 * END-OF-LIFE frame compatibility module
230 GDB's internal frame infrastructure has been completely rewritten.
231 The new infrastructure making it possible to support key new features
232 including DWARF 2 Call Frame Information. To aid in the task of
233 migrating old configurations to this new infrastructure, a
234 compatibility module, that allowed old configurations to continue to
235 work, was also included.
237 GDB 6.2 will be the last release to include this frame compatibility
238 module. This change directly impacts the following configurations:
248 Unless there is activity to revive these configurations, they will be
249 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
251 * REMOVED configurations and files
253 Sun 3, running SunOS 3 m68*-*-sunos3*
254 Sun 3, running SunOS 4 m68*-*-sunos4*
255 Sun 2, running SunOS 3 m68000-*-sunos3*
256 Sun 2, running SunOS 4 m68000-*-sunos4*
257 Motorola 680x0 running LynxOS m68*-*-lynxos*
258 AT&T 3b1/Unix pc m68*-att-*
259 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
260 decstation mips-dec-* mips-little-*
261 riscos mips-*-riscos* mips-*-sysv*
263 sysv mips*-*-sysv4* (IRIX 5/6 not included)
265 *** Changes in GDB 6.1.1:
267 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
269 The TUI (Text-mode User Interface) is now built as part of a default
270 GDB configuration. It is enabled by either selecting the TUI with the
271 command line option "-i=tui" or by running the separate "gdbtui"
272 program. For more information on the TUI, see the manual "Debugging
275 * Pending breakpoint support (also included in GDB 6.1)
277 Support has been added to allow you to specify breakpoints in shared
278 libraries that have not yet been loaded. If a breakpoint location
279 cannot be found, and the "breakpoint pending" option is set to auto,
280 GDB queries you if you wish to make the breakpoint pending on a future
281 shared-library load. If and when GDB resolves the breakpoint symbol,
282 the pending breakpoint is removed as one or more regular breakpoints
285 Pending breakpoints are very useful for GCJ Java debugging.
287 * Fixed ISO-C build problems
289 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
290 non ISO-C code that stopped them being built using a more strict ISO-C
291 compiler (e.g., IBM's C compiler).
293 * Fixed build problem on IRIX 5
295 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
296 wasn't able to compile compile on an IRIX 5 system.
298 * Added execute permission to gdb/gdbserver/configure
300 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
301 permission. This bug would cause configure to fail on a number of
302 systems (Solaris, IRIX). Ref: server/519.
304 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
306 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
307 has been updated to use constant array sizes.
309 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
311 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
312 its generated DWARF Call Frame Info. This encoding was causing GDB to
313 panic, that panic has been fixed. Ref: gdb/1628.
315 * Fixed a problem when examining parameters in shared library code.
317 When examining parameters in optimized shared library code generated
318 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
319 not available''. GDB now correctly displays the variable's value.
321 *** Changes in GDB 6.1:
323 * Removed --with-mmalloc
325 Support for the mmalloc memory manager has been removed, as it
326 conflicted with the internal gdb byte cache.
328 * Changes in AMD64 configurations
330 The AMD64 target now includes the %cs and %ss registers. As a result
331 the AMD64 remote protocol has changed; this affects the floating-point
332 and SSE registers. If you rely on those registers for your debugging,
333 you should upgrade gdbserver on the remote side.
335 * Revised SPARC target
337 The SPARC target has been completely revised, incorporating the
338 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
339 support for LynxOS and SunOS 4 has been dropped. Calling functions
340 from within GDB on operating systems with a non-executable stack
341 (Solaris, OpenBSD) now works.
345 GDB has a new C++ demangler which does a better job on the mangled
346 names generated by current versions of g++. It also runs faster, so
347 with this and other changes gdb should now start faster on large C++
350 * DWARF 2 Location Expressions
352 GDB support for location expressions has been extended to support function
353 arguments and frame bases. Older versions of GDB could crash when they
356 * C++ nested types and namespaces
358 GDB's support for nested types and namespaces in C++ has been
359 improved, especially if you use the DWARF 2 debugging format. (This
360 is the default for recent versions of GCC on most platforms.)
361 Specifically, if you have a class "Inner" defined within a class or
362 namespace "Outer", then GDB realizes that the class's name is
363 "Outer::Inner", not simply "Inner". This should greatly reduce the
364 frequency of complaints about not finding RTTI symbols. In addition,
365 if you are stopped at inside of a function defined within a namespace,
366 GDB modifies its name lookup accordingly.
368 * New native configurations
370 NetBSD/amd64 x86_64-*-netbsd*
371 OpenBSD/amd64 x86_64-*-openbsd*
372 OpenBSD/alpha alpha*-*-openbsd*
373 OpenBSD/sparc sparc-*-openbsd*
374 OpenBSD/sparc64 sparc64-*-openbsd*
376 * New debugging protocols
378 M32R with SDI protocol m32r-*-elf*
380 * "set prompt-escape-char" command deleted.
382 The command "set prompt-escape-char" has been deleted. This command,
383 and its very obscure effet on GDB's prompt, was never documented,
384 tested, nor mentioned in the NEWS file.
386 * OBSOLETE configurations and files
388 Configurations that have been declared obsolete in this release have
389 been commented out. Unless there is activity to revive these
390 configurations, the next release of GDB will have their sources
393 Sun 3, running SunOS 3 m68*-*-sunos3*
394 Sun 3, running SunOS 4 m68*-*-sunos4*
395 Sun 2, running SunOS 3 m68000-*-sunos3*
396 Sun 2, running SunOS 4 m68000-*-sunos4*
397 Motorola 680x0 running LynxOS m68*-*-lynxos*
398 AT&T 3b1/Unix pc m68*-att-*
399 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
400 decstation mips-dec-* mips-little-*
401 riscos mips-*-riscos* mips-*-sysv*
403 sysv mips*-*-sysv4* (IRIX 5/6 not included)
405 * REMOVED configurations and files
407 SGI Irix-4.x mips-sgi-irix4 or iris4
408 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
409 Z8000 simulator z8k-zilog-none or z8ksim
410 Matsushita MN10200 w/simulator mn10200-*-*
411 H8/500 simulator h8500-hitachi-hms or h8500hms
412 HP/PA running BSD hppa*-*-bsd*
413 HP/PA running OSF/1 hppa*-*-osf*
414 HP/PA Pro target hppa*-*-pro*
415 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
416 386BSD i[3456]86-*-bsd*
417 Sequent family i[3456]86-sequent-sysv4*
418 i[3456]86-sequent-sysv*
419 i[3456]86-sequent-bsd*
420 SPARC running LynxOS sparc-*-lynxos*
421 SPARC running SunOS 4 sparc-*-sunos4*
422 Tsqware Sparclet sparclet-*-*
423 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
425 *** Changes in GDB 6.0:
429 Support for debugging the Objective-C programming language has been
432 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
434 DWARF 2's Call Frame Information makes available compiler generated
435 information that more exactly describes the program's run-time stack.
436 By using this information, GDB is able to provide more robust stack
439 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
440 have been updated to use a new backtrace mechanism which includes
445 GDB's remote protocol has been extended to include support for hosted
446 file I/O (where the remote target uses GDB's file system). See GDB's
447 remote protocol documentation for details.
449 * All targets using the new architecture framework.
451 All of GDB's targets have been updated to use the new internal
452 architecture framework. The way is now open for future GDB releases
453 to include cross-architecture native debugging support (i386 on amd64,
456 * GNU/Linux's Thread Local Storage (TLS)
458 GDB now includes support for for the GNU/Linux implementation of
459 per-thread variables.
461 * GNU/Linux's Native POSIX Thread Library (NPTL)
463 GDB's thread code has been updated to work with either the new
464 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
466 * Separate debug info.
468 GDB, in conjunction with BINUTILS, now supports a mechanism for
469 automatically loading debug information from a separate file. Instead
470 of shipping full debug and non-debug versions of system libraries,
471 system integrators can now instead ship just the stripped libraries
472 and optional debug files.
474 * DWARF 2 Location Expressions
476 DWARF 2 Location Expressions allow the compiler to more completely
477 describe the location of variables (even in optimized code) to the
480 GDB now includes preliminary support for location expressions (support
481 for DW_OP_piece is still missing).
485 A number of long standing bugs that caused GDB to die while starting a
486 Java application have been fixed. GDB's Java support is now
487 considered "useable".
489 * GNU/Linux support for fork, vfork, and exec.
491 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
492 commands are now implemented for GNU/Linux. They require a 2.5.x or later
495 * GDB supports logging output to a file
497 There are two new commands, "set logging" and "show logging", which can be
498 used to capture GDB's output to a file.
500 * The meaning of "detach" has changed for gdbserver
502 The "detach" command will now resume the application, as documented. To
503 disconnect from gdbserver and leave it stopped, use the new "disconnect"
506 * d10v, m68hc11 `regs' command deprecated
508 The `info registers' command has been updated so that it displays the
509 registers using a format identical to the old `regs' command.
513 A new command, "maint set profile on/off", has been added. This command can
514 be used to enable or disable profiling while running GDB, to profile a
515 session or a set of commands. In addition there is a new configure switch,
516 "--enable-profiling", which will cause GDB to be compiled with profiling
517 data, for more informative profiling results.
519 * Default MI syntax changed to "mi2".
521 The default MI (machine interface) syntax, enabled by the command line
522 option "-i=mi", has been changed to "mi2". The previous MI syntax,
523 "mi1", can be enabled by specifying the option "-i=mi1".
525 Support for the original "mi0" syntax (included in GDB 5.0) has been
528 Fix for gdb/192: removed extraneous space when displaying frame level.
529 Fix for gdb/672: update changelist is now output in mi list format.
530 Fix for gdb/702: a -var-assign that updates the value now shows up
531 in a subsequent -var-update.
533 * New native configurations.
535 FreeBSD/amd64 x86_64-*-freebsd*
537 * Multi-arched targets.
539 HP/PA HPUX11 hppa*-*-hpux*
540 Renesas M32R/D w/simulator m32r-*-elf*
542 * OBSOLETE configurations and files
544 Configurations that have been declared obsolete in this release have
545 been commented out. Unless there is activity to revive these
546 configurations, the next release of GDB will have their sources
549 Z8000 simulator z8k-zilog-none or z8ksim
550 Matsushita MN10200 w/simulator mn10200-*-*
551 H8/500 simulator h8500-hitachi-hms or h8500hms
552 HP/PA running BSD hppa*-*-bsd*
553 HP/PA running OSF/1 hppa*-*-osf*
554 HP/PA Pro target hppa*-*-pro*
555 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
556 Sequent family i[3456]86-sequent-sysv4*
557 i[3456]86-sequent-sysv*
558 i[3456]86-sequent-bsd*
559 Tsqware Sparclet sparclet-*-*
560 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
562 * REMOVED configurations and files
565 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
566 IBM AIX PS/2 i[3456]86-*-aix
567 i386 running Mach 3.0 i[3456]86-*-mach3*
568 i386 running Mach i[3456]86-*-mach*
569 i386 running OSF/1 i[3456]86-*osf1mk*
570 HP/Apollo 68k Family m68*-apollo*-sysv*,
572 m68*-hp-bsd*, m68*-hp-hpux*
573 Argonaut Risc Chip (ARC) arc-*-*
574 Mitsubishi D30V d30v-*-*
575 Fujitsu FR30 fr30-*-elf*
576 OS/9000 i[34]86-*-os9k
577 I960 with MON960 i960-*-coff
579 * MIPS $fp behavior changed
581 The convenience variable $fp, for the MIPS, now consistently returns
582 the address of the current frame's base. Previously, depending on the
583 context, $fp could refer to either $sp or the current frame's base
584 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
585 The GNU Source-Level Debugger''.
587 *** Changes in GDB 5.3:
589 * GNU/Linux shared library multi-threaded performance improved.
591 When debugging a multi-threaded application on GNU/Linux, GDB now uses
592 `/proc', in preference to `ptrace' for memory reads. This may result
593 in an improvement in the start-up time of multi-threaded, shared
594 library applications when run under GDB. One GDB user writes: ``loads
595 shared libs like mad''.
597 * ``gdbserver'' now supports multi-threaded applications on some targets
599 Support for debugging multi-threaded applications which use
600 the GNU/Linux LinuxThreads package has been added for
601 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
602 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
604 * GDB now supports C/C++ preprocessor macros.
606 GDB now expands preprocessor macro invocations in C/C++ expressions,
607 and provides various commands for showing macro definitions and how
610 The new command `macro expand EXPRESSION' expands any macro
611 invocations in expression, and shows the result.
613 The new command `show macro MACRO-NAME' shows the definition of the
614 macro named MACRO-NAME, and where it was defined.
616 Most compilers don't include information about macros in the debugging
617 information by default. In GCC 3.1, for example, you need to compile
618 your program with the options `-gdwarf-2 -g3'. If the macro
619 information is present in the executable, GDB will read it.
621 * Multi-arched targets.
623 DEC Alpha (partial) alpha*-*-*
624 DEC VAX (partial) vax-*-*
626 National Semiconductor NS32000 (partial) ns32k-*-*
627 Motorola 68000 (partial) m68k-*-*
628 Motorola MCORE mcore-*-*
632 Fujitsu FRV architecture added by Red Hat frv*-*-*
635 * New native configurations
637 Alpha NetBSD alpha*-*-netbsd*
638 SH NetBSD sh*-*-netbsdelf*
639 MIPS NetBSD mips*-*-netbsd*
640 UltraSPARC NetBSD sparc64-*-netbsd*
642 * OBSOLETE configurations and files
644 Configurations that have been declared obsolete in this release have
645 been commented out. Unless there is activity to revive these
646 configurations, the next release of GDB will have their sources
649 Mitsubishi D30V d30v-*-*
650 OS/9000 i[34]86-*-os9k
651 IBM AIX PS/2 i[3456]86-*-aix
652 Fujitsu FR30 fr30-*-elf*
653 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
654 Argonaut Risc Chip (ARC) arc-*-*
655 i386 running Mach 3.0 i[3456]86-*-mach3*
656 i386 running Mach i[3456]86-*-mach*
657 i386 running OSF/1 i[3456]86-*osf1mk*
658 HP/Apollo 68k Family m68*-apollo*-sysv*,
660 m68*-hp-bsd*, m68*-hp-hpux*
661 I960 with MON960 i960-*-coff
665 CHILL, a Pascal like language used by telecommunications companies.
667 * REMOVED configurations and files
669 AMD 29k family via UDI a29k-amd-udi, udi29k
670 A29K VxWorks a29k-*-vxworks
671 AMD 29000 embedded, using EBMON a29k-none-none
672 AMD 29000 embedded with COFF a29k-none-coff
673 AMD 29000 embedded with a.out a29k-none-aout
675 testsuite/gdb.hp/gdb.threads-hp/ directory
677 * New command "set max-user-call-depth <nnn>"
679 This command allows the user to limit the call depth of user-defined
680 commands. The default is 1024.
682 * Changes in FreeBSD/i386 native debugging.
684 Support for the "generate-core-file" has been added.
686 * New commands "dump", "append", and "restore".
688 These commands allow data to be copied from target memory
689 to a bfd-format or binary file (dump and append), and back
690 from a file into memory (restore).
692 * Improved "next/step" support on multi-processor Alpha Tru64.
694 The previous single-step mechanism could cause unpredictable problems,
695 including the random appearance of SIGSEGV or SIGTRAP signals. The use
696 of a software single-step mechanism prevents this.
698 *** Changes in GDB 5.2.1:
706 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
707 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
708 Fix, by Joel Brobecker imported from mainline.
710 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
711 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
712 Fix, by Fred Fish, imported from mainline.
714 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
715 Surprisingly enough, it works now.
716 By Michal Ludvig, imported from mainline.
718 i386 hardware watchpoint support:
719 avoid misses on second run for some targets.
720 By Pierre Muller, imported from mainline.
722 *** Changes in GDB 5.2:
724 * New command "set trust-readonly-sections on[off]".
726 This command is a hint that tells gdb that read-only sections
727 really are read-only (ie. that their contents will not change).
728 In this mode, gdb will go to the object file rather than the
729 target to read memory from read-only sections (such as ".text").
730 This can be a significant performance improvement on some
731 (notably embedded) targets.
733 * New command "generate-core-file" (or "gcore").
735 This new gdb command allows the user to drop a core file of the child
736 process state at any time. So far it's been implemented only for
737 GNU/Linux and Solaris, but should be relatively easily ported to other
738 hosts. Argument is core file name (defaults to core.<pid>).
740 * New command line option
742 GDB now accepts --pid or -p followed by a process id.
744 * Change in command line behavior -- corefiles vs. process ids.
746 There is a subtle behavior in the way in which GDB handles
747 command line arguments. The first non-flag argument is always
748 a program to debug, but the second non-flag argument may either
749 be a corefile or a process id. Previously, GDB would attempt to
750 open the second argument as a corefile, and if that failed, would
751 issue a superfluous error message and then attempt to attach it as
752 a process. Now, if the second argument begins with a non-digit,
753 it will be treated as a corefile. If it begins with a digit,
754 GDB will attempt to attach it as a process, and if no such process
755 is found, will then attempt to open it as a corefile.
757 * Changes in ARM configurations.
759 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
760 configuration is fully multi-arch.
762 * New native configurations
764 ARM NetBSD arm*-*-netbsd*
765 x86 OpenBSD i[3456]86-*-openbsd*
766 AMD x86-64 running GNU/Linux x86_64-*-linux-*
767 Sparc64 running FreeBSD sparc64-*-freebsd*
771 Sanyo XStormy16 xstormy16-elf
773 * OBSOLETE configurations and files
775 Configurations that have been declared obsolete in this release have
776 been commented out. Unless there is activity to revive these
777 configurations, the next release of GDB will have their sources
780 AMD 29k family via UDI a29k-amd-udi, udi29k
781 A29K VxWorks a29k-*-vxworks
782 AMD 29000 embedded, using EBMON a29k-none-none
783 AMD 29000 embedded with COFF a29k-none-coff
784 AMD 29000 embedded with a.out a29k-none-aout
786 testsuite/gdb.hp/gdb.threads-hp/ directory
788 * REMOVED configurations and files
790 TI TMS320C80 tic80-*-*
792 PowerPC Solaris powerpcle-*-solaris*
793 PowerPC Windows NT powerpcle-*-cygwin32
794 PowerPC Netware powerpc-*-netware*
795 Harris/CXUX m88k m88*-harris-cxux*
796 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
797 ns32k-utek-sysv* ns32k-utek-*
798 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
799 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
800 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
801 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
802 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
804 * Changes to command line processing
806 The new `--args' feature can be used to specify command-line arguments
807 for the inferior from gdb's command line.
809 * Changes to key bindings
811 There is a new `operate-and-get-next' function bound to `C-o'.
813 *** Changes in GDB 5.1.1
815 Fix compile problem on DJGPP.
817 Fix a problem with floating-point registers on the i386 being
820 Fix to stop GDB crashing on .debug_str debug info.
822 Numerous documentation fixes.
824 Numerous testsuite fixes.
826 *** Changes in GDB 5.1:
828 * New native configurations
830 Alpha FreeBSD alpha*-*-freebsd*
831 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
832 MIPS GNU/Linux mips*-*-linux*
833 MIPS SGI Irix 6.x mips*-sgi-irix6*
835 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
839 Motorola 68HC11 and 68HC12 m68hc11-elf
841 UltraSparc running GNU/Linux sparc64-*-linux*
843 * OBSOLETE configurations and files
845 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
846 Harris/CXUX m88k m88*-harris-cxux*
847 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
848 ns32k-utek-sysv* ns32k-utek-*
849 TI TMS320C80 tic80-*-*
851 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
852 PowerPC Solaris powerpcle-*-solaris*
853 PowerPC Windows NT powerpcle-*-cygwin32
854 PowerPC Netware powerpc-*-netware*
855 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
856 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
857 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
858 Apple Macintosh (MPW) host N/A
860 stuff.c (Program to stuff files into a specially prepared space in kdb)
861 kdb-start.c (Main loop for the standalone kernel debugger)
863 Configurations that have been declared obsolete in this release have
864 been commented out. Unless there is activity to revive these
865 configurations, the next release of GDB will have their sources
868 * REMOVED configurations and files
870 Altos 3068 m68*-altos-*
871 Convex c1-*-*, c2-*-*
873 ARM RISCix arm-*-* (as host)
877 * GDB has been converted to ISO C.
879 GDB's source code has been converted to ISO C. In particular, the
880 sources are fully protoized, and rely on standard headers being
885 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
887 * The MI enabled by default.
889 The new machine oriented interface (MI) introduced in GDB 5.0 has been
890 revised and enabled by default. Packages which use GDB as a debugging
891 engine behind a UI or another front end are encouraged to switch to
892 using the GDB/MI interface, instead of the old annotations interface
893 which is now deprecated.
895 * Support for debugging Pascal programs.
897 GDB now includes support for debugging Pascal programs. The following
898 main features are supported:
900 - Pascal-specific data types such as sets;
902 - automatic recognition of Pascal sources based on file-name
905 - Pascal-style display of data types, variables, and functions;
907 - a Pascal expression parser.
909 However, some important features are not yet supported.
911 - Pascal string operations are not supported at all;
913 - there are some problems with boolean types;
915 - Pascal type hexadecimal constants are not supported
916 because they conflict with the internal variables format;
918 - support for Pascal objects and classes is not full yet;
920 - unlike Pascal, GDB is case-sensitive for symbol names.
922 * Changes in completion.
924 Commands such as `shell', `run' and `set args', which pass arguments
925 to inferior programs, now complete on file names, similar to what
926 users expect at the shell prompt.
928 Commands which accept locations, such as `disassemble', `print',
929 `breakpoint', `until', etc. now complete on filenames as well as
930 program symbols. Thus, if you type "break foob TAB", and the source
931 files linked into the programs include `foobar.c', that file name will
932 be one of the candidates for completion. However, file names are not
933 considered for completion after you typed a colon that delimits a file
934 name from a name of a function in that file, as in "break foo.c:bar".
936 `set demangle-style' completes on available demangling styles.
938 * New platform-independent commands:
940 It is now possible to define a post-hook for a command as well as a
941 hook that runs before the command. For more details, see the
942 documentation of `hookpost' in the GDB manual.
944 * Changes in GNU/Linux native debugging.
946 Support for debugging multi-threaded programs has been completely
947 revised for all platforms except m68k and sparc. You can now debug as
948 many threads as your system allows you to have.
950 Attach/detach is supported for multi-threaded programs.
952 Support for SSE registers was added for x86. This doesn't work for
953 multi-threaded programs though.
955 * Changes in MIPS configurations.
957 Multi-arch support is enabled for all MIPS configurations.
959 GDB can now be built as native debugger on SGI Irix 6.x systems for
960 debugging n32 executables. (Debugging 64-bit executables is not yet
963 * Unified support for hardware watchpoints in all x86 configurations.
965 Most (if not all) native x86 configurations support hardware-assisted
966 breakpoints and watchpoints in a unified manner. This support
967 implements debug register sharing between watchpoints, which allows to
968 put a virtually infinite number of watchpoints on the same address,
969 and also supports watching regions up to 16 bytes with several debug
972 The new maintenance command `maintenance show-debug-regs' toggles
973 debugging print-outs in functions that insert, remove, and test
974 watchpoints and hardware breakpoints.
976 * Changes in the DJGPP native configuration.
978 New command ``info dos sysinfo'' displays assorted information about
979 the CPU, OS, memory, and DPMI server.
981 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
982 display information about segment descriptors stored in GDT, LDT, and
985 New commands ``info dos pde'' and ``info dos pte'' display entries
986 from Page Directory and Page Tables (for now works with CWSDPMI only).
987 New command ``info dos address-pte'' displays the Page Table entry for
988 a given linear address.
990 GDB can now pass command lines longer than 126 characters to the
991 program being debugged (requires an update to the libdbg.a library
992 which is part of the DJGPP development kit).
994 DWARF2 debug info is now supported.
996 It is now possible to `step' and `next' through calls to `longjmp'.
998 * Changes in documentation.
1000 All GDB documentation was converted to GFDL, the GNU Free
1001 Documentation License.
1003 Tracepoints-related commands are now fully documented in the GDB
1006 TUI, the Text-mode User Interface, is now documented in the manual.
1008 Tracepoints-related commands are now fully documented in the GDB
1011 The "GDB Internals" manual now has an index. It also includes
1012 documentation of `ui_out' functions, GDB coding standards, x86
1013 hardware watchpoints, and memory region attributes.
1015 * GDB's version number moved to ``version.in''
1017 The Makefile variable VERSION has been replaced by the file
1018 ``version.in''. People creating GDB distributions should update the
1019 contents of this file.
1023 GUD support is now a standard part of the EMACS distribution.
1025 *** Changes in GDB 5.0:
1027 * Improved support for debugging FP programs on x86 targets
1029 Unified and much-improved support for debugging floating-point
1030 programs on all x86 targets. In particular, ``info float'' now
1031 displays the FP registers in the same format on all x86 targets, with
1032 greater level of detail.
1034 * Improvements and bugfixes in hardware-assisted watchpoints
1036 It is now possible to watch array elements, struct members, and
1037 bitfields with hardware-assisted watchpoints. Data-read watchpoints
1038 on x86 targets no longer erroneously trigger when the address is
1041 * Improvements in the native DJGPP version of GDB
1043 The distribution now includes all the scripts and auxiliary files
1044 necessary to build the native DJGPP version on MS-DOS/MS-Windows
1045 machines ``out of the box''.
1047 The DJGPP version can now debug programs that use signals. It is
1048 possible to catch signals that happened in the debuggee, deliver
1049 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
1050 would kill the program being debugged.) Programs that hook hardware
1051 interrupts (keyboard, timer, etc.) can also be debugged.
1053 It is now possible to debug DJGPP programs that redirect their
1054 standard handles or switch them to raw (as opposed to cooked) mode, or
1055 even close them. The command ``run < foo > bar'' works as expected,
1056 and ``info terminal'' reports useful information about the debuggee's
1057 terminal, including raw/cooked mode, redirection, etc.
1059 The DJGPP version now uses termios functions for console I/O, which
1060 enables debugging graphics programs. Interrupting GDB with Ctrl-C
1063 DOS-style file names with drive letters are now fully supported by
1066 It is now possible to debug DJGPP programs that switch their working
1067 directory. It is also possible to rerun the debuggee any number of
1068 times without restarting GDB; thus, you can use the same setup,
1069 breakpoints, etc. for many debugging sessions.
1071 * New native configurations
1073 ARM GNU/Linux arm*-*-linux*
1074 PowerPC GNU/Linux powerpc-*-linux*
1078 Motorola MCore mcore-*-*
1079 x86 VxWorks i[3456]86-*-vxworks*
1080 PowerPC VxWorks powerpc-*-vxworks*
1081 TI TMS320C80 tic80-*-*
1083 * OBSOLETE configurations
1085 Altos 3068 m68*-altos-*
1086 Convex c1-*-*, c2-*-*
1088 ARM RISCix arm-*-* (as host)
1091 Configurations that have been declared obsolete will be commented out,
1092 but the code will be left in place. If there is no activity to revive
1093 these configurations before the next release of GDB, the sources will
1094 be permanently REMOVED.
1096 * Gould support removed
1098 Support for the Gould PowerNode and NP1 has been removed.
1100 * New features for SVR4
1102 On SVR4 native platforms (such as Solaris), if you attach to a process
1103 without first loading a symbol file, GDB will now attempt to locate and
1104 load symbols from the running process's executable file.
1106 * Many C++ enhancements
1108 C++ support has been greatly improved. Overload resolution now works properly
1109 in almost all cases. RTTI support is on the way.
1111 * Remote targets can connect to a sub-program
1113 A popen(3) style serial-device has been added. This device starts a
1114 sub-process (such as a stand-alone simulator) and then communicates
1115 with that. The sub-program to run is specified using the syntax
1116 ``|<program> <args>'' vis:
1118 (gdb) set remotedebug 1
1119 (gdb) target extended-remote |mn10300-elf-sim program-args
1121 * MIPS 64 remote protocol
1123 A long standing bug in the mips64 remote protocol where by GDB
1124 expected certain 32 bit registers (ex SR) to be transfered as 32
1125 instead of 64 bits has been fixed.
1127 The command ``set remote-mips64-transfers-32bit-regs on'' has been
1128 added to provide backward compatibility with older versions of GDB.
1130 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
1132 The command ``set remotebinarydownload'' command has been replaced by
1133 ``set remote X-packet''. Other commands in ``set remote'' family
1134 include ``set remote P-packet''.
1136 * Breakpoint commands accept ranges.
1138 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
1139 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
1140 ``tracepoint passcount'' also accepts a range of tracepoints.
1142 * ``apropos'' command added.
1144 The ``apropos'' command searches through command names and
1145 documentation strings, printing out matches, making it much easier to
1146 try to find a command that does what you are looking for.
1150 A new machine oriented interface (MI) has been added to GDB. This
1151 interface is designed for debug environments running GDB as a separate
1152 process. This is part of the long term libGDB project. See the
1153 "GDB/MI" chapter of the GDB manual for further information. It can be
1154 enabled by configuring with:
1156 .../configure --enable-gdbmi
1158 *** Changes in GDB-4.18:
1160 * New native configurations
1162 HP-UX 10.20 hppa*-*-hpux10.20
1163 HP-UX 11.x hppa*-*-hpux11.0*
1164 M68K GNU/Linux m68*-*-linux*
1168 Fujitsu FR30 fr30-*-elf*
1169 Intel StrongARM strongarm-*-*
1170 Mitsubishi D30V d30v-*-*
1172 * OBSOLETE configurations
1174 Gould PowerNode, NP1 np1-*-*, pn-*-*
1176 Configurations that have been declared obsolete will be commented out,
1177 but the code will be left in place. If there is no activity to revive
1178 these configurations before the next release of GDB, the sources will
1179 be permanently REMOVED.
1183 As a compatibility experiment, GDB's source files buildsym.h and
1184 buildsym.c have been converted to pure standard C, no longer
1185 containing any K&R compatibility code. We believe that all systems in
1186 use today either come with a standard C compiler, or have a GCC port
1187 available. If this is not true, please report the affected
1188 configuration to bug-gdb@gnu.org immediately. See the README file for
1189 information about getting a standard C compiler if you don't have one
1194 GDB now uses readline 2.2.
1196 * set extension-language
1198 You can now control the mapping between filename extensions and source
1199 languages by using the `set extension-language' command. For instance,
1200 you can ask GDB to treat .c files as C++ by saying
1201 set extension-language .c c++
1202 The command `info extensions' lists all of the recognized extensions
1203 and their associated languages.
1205 * Setting processor type for PowerPC and RS/6000
1207 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
1208 you can use the `set processor' command to specify what variant of the
1209 PowerPC family you are debugging. The command
1213 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
1214 following PowerPC and RS6000 variants:
1216 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
1217 rs6000 IBM RS6000 ("POWER") architecture, user-level view
1219 403GC IBM PowerPC 403GC
1220 505 Motorola PowerPC 505
1221 860 Motorola PowerPC 860 or 850
1222 601 Motorola PowerPC 601
1223 602 Motorola PowerPC 602
1224 603 Motorola/IBM PowerPC 603 or 603e
1225 604 Motorola PowerPC 604 or 604e
1226 750 Motorola/IBM PowerPC 750 or 750
1228 At the moment, this command just tells GDB what to name the
1229 special-purpose processor registers. Since almost all the affected
1230 registers are inaccessible to user-level programs, this command is
1231 only useful for remote debugging in its present form.
1235 Thanks to a major code donation from Hewlett-Packard, GDB now has much
1236 more extensive support for HP-UX. Added features include shared
1237 library support, kernel threads and hardware watchpoints for 11.00,
1238 support for HP's ANSI C and C++ compilers, and a compatibility mode
1239 for xdb and dbx commands.
1243 HP's donation includes the new concept of catchpoints, which is a
1244 generalization of the old catch command. On HP-UX, it is now possible
1245 to catch exec, fork, and vfork, as well as library loading.
1247 This means that the existing catch command has changed; its first
1248 argument now specifies the type of catch to be set up. See the
1249 output of "help catch" for a list of catchpoint types.
1251 * Debugging across forks
1253 On HP-UX, you can choose which process to debug when a fork() happens
1258 HP has donated a curses-based terminal user interface (TUI). To get
1259 it, build with --enable-tui. Although this can be enabled for any
1260 configuration, at present it only works for native HP debugging.
1262 * GDB remote protocol additions
1264 A new protocol packet 'X' that writes binary data is now available.
1265 Default behavior is to try 'X', then drop back to 'M' if the stub
1266 fails to respond. The settable variable `remotebinarydownload'
1267 allows explicit control over the use of 'X'.
1269 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1270 full 64-bit address. The command
1272 set remoteaddresssize 32
1274 can be used to revert to the old behaviour. For existing remote stubs
1275 the change should not be noticed, as the additional address information
1278 In order to assist in debugging stubs, you may use the maintenance
1279 command `packet' to send any text string to the stub. For instance,
1281 maint packet heythere
1283 sends the packet "$heythere#<checksum>". Note that it is very easy to
1284 disrupt a debugging session by sending the wrong packet at the wrong
1287 The compare-sections command allows you to compare section data on the
1288 target to what is in the executable file without uploading or
1289 downloading, by comparing CRC checksums.
1291 * Tracing can collect general expressions
1293 You may now collect general expressions at tracepoints. This requires
1294 further additions to the target-side stub; see tracepoint.c and
1295 doc/agentexpr.texi for further details.
1297 * mask-address variable for Mips
1299 For Mips targets, you may control the zeroing of the upper 32 bits of
1300 a 64-bit address by entering `set mask-address on'. This is mainly
1301 of interest to users of embedded R4xxx and R5xxx processors.
1303 * Higher serial baud rates
1305 GDB's serial code now allows you to specify baud rates 57600, 115200,
1306 230400, and 460800 baud. (Note that your host system may not be able
1307 to achieve all of these rates.)
1311 The i960 configuration now includes an initial implementation of a
1312 builtin simulator, contributed by Jim Wilson.
1315 *** Changes in GDB-4.17:
1317 * New native configurations
1319 Alpha GNU/Linux alpha*-*-linux*
1320 Unixware 2.x i[3456]86-unixware2*
1321 Irix 6.x mips*-sgi-irix6*
1322 PowerPC GNU/Linux powerpc-*-linux*
1323 PowerPC Solaris powerpcle-*-solaris*
1324 Sparc GNU/Linux sparc-*-linux*
1325 Motorola sysV68 R3V7.1 m68k-motorola-sysv
1329 Argonaut Risc Chip (ARC) arc-*-*
1330 Hitachi H8/300S h8300*-*-*
1331 Matsushita MN10200 w/simulator mn10200-*-*
1332 Matsushita MN10300 w/simulator mn10300-*-*
1333 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1334 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1335 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1336 Mitsubishi D10V w/simulator d10v-*-*
1337 Mitsubishi M32R/D w/simulator m32r-*-elf*
1338 Tsqware Sparclet sparclet-*-*
1339 NEC V850 w/simulator v850-*-*
1341 * New debugging protocols
1343 ARM with RDI protocol arm*-*-*
1344 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1345 DDB and LSI variants of PMON protocol mips*-*-*
1346 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1347 PowerPC with SDS protocol powerpc{,le}-*-eabi
1348 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1352 All configurations can now understand and use the DWARF 2 debugging
1353 format. The choice is automatic, if the symbol file contains DWARF 2
1358 GDB now includes basic Java language support. This support is
1359 only useful with Java compilers that produce native machine code.
1361 * solib-absolute-prefix and solib-search-path
1363 For SunOS and SVR4 shared libraries, you may now set the prefix for
1364 loading absolute shared library symbol files, and the search path for
1365 locating non-absolute shared library symbol files.
1367 * Live range splitting
1369 GDB can now effectively debug code for which GCC has performed live
1370 range splitting as part of its optimization. See gdb/doc/LRS for
1371 more details on the expected format of the stabs information.
1375 GDB's support for the GNU Hurd, including thread debugging, has been
1376 updated to work with current versions of the Hurd.
1380 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1381 instruction set. ARM GDB automatically detects when Thumb
1382 instructions are in use, and adjusts disassembly and backtracing
1387 GDB's MIPS target configurations now handle the MIP16 16-bit
1392 GDB now includes support for overlays; if an executable has been
1393 linked such that multiple sections are based at the same address, GDB
1394 will decide which section to use for symbolic info. You can choose to
1395 control the decision manually, using overlay commands, or implement
1396 additional target-side support and use "overlay load-target" to bring
1397 in the overlay mapping. Do "help overlay" for more detail.
1401 The command "info symbol <address>" displays information about
1402 the symbol at the specified address.
1406 The standard remote protocol now includes an extension that allows
1407 asynchronous collection and display of trace data. This requires
1408 extensive support in the target-side debugging stub. Tracing mode
1409 includes a new interaction mode in GDB and new commands: see the
1410 file tracepoint.c for more details.
1414 Configurations for embedded MIPS now include a simulator contributed
1415 by Cygnus Solutions. The simulator supports the instruction sets
1416 of most MIPS variants.
1420 Sparc configurations may now include the ERC32 simulator contributed
1421 by the European Space Agency. The simulator is not built into
1422 Sparc targets by default; configure with --enable-sim to include it.
1426 For target configurations that may include multiple variants of a
1427 basic architecture (such as MIPS and SH), you may now set the
1428 architecture explicitly. "set arch" sets, "info arch" lists
1429 the possible architectures.
1431 *** Changes in GDB-4.16:
1433 * New native configurations
1435 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1436 M68K NetBSD m68k-*-netbsd*
1437 PowerPC AIX 4.x powerpc-*-aix*
1438 PowerPC MacOS powerpc-*-macos*
1439 PowerPC Windows NT powerpcle-*-cygwin32
1440 RS/6000 AIX 4.x rs6000-*-aix4*
1444 ARM with RDP protocol arm-*-*
1445 I960 with MON960 i960-*-coff
1446 MIPS VxWorks mips*-*-vxworks*
1447 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1448 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1450 Matra Sparclet sparclet-*-*
1454 The powerpc-eabi configuration now includes the PSIM simulator,
1455 contributed by Andrew Cagney, with assistance from Mike Meissner.
1456 PSIM is a very elaborate model of the PowerPC, including not only
1457 basic instruction set execution, but also details of execution unit
1458 performance and I/O hardware. See sim/ppc/README for more details.
1462 GDB now works with Solaris 2.5.
1464 * Windows 95/NT native
1466 GDB will now work as a native debugger on Windows 95 and Windows NT.
1467 To build it from source, you must use the "gnu-win32" environment,
1468 which uses a DLL to emulate enough of Unix to run the GNU tools.
1469 Further information, binaries, and sources are available at
1470 ftp.cygnus.com, under pub/gnu-win32.
1472 * dont-repeat command
1474 If a user-defined command includes the command `dont-repeat', then the
1475 command will not be repeated if the user just types return. This is
1476 useful if the command is time-consuming to run, so that accidental
1477 extra keystrokes don't run the same command many times.
1479 * Send break instead of ^C
1481 The standard remote protocol now includes an option to send a break
1482 rather than a ^C to the target in order to interrupt it. By default,
1483 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1485 * Remote protocol timeout
1487 The standard remote protocol includes a new variable `remotetimeout'
1488 that allows you to set the number of seconds before GDB gives up trying
1489 to read from the target. The default value is 2.
1491 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1493 By default GDB will automatically keep track of objects as they are
1494 loaded and unloaded by the dynamic linker. By using the command `set
1495 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1496 when shared library events occur, thus allowing you to set breakpoints
1497 in shared libraries which are explicitly loaded by the inferior.
1499 Note this feature does not work on hpux8. On hpux9 you must link
1500 /usr/lib/end.o into your program. This feature should work
1501 automatically on hpux10.
1503 * Irix 5.x hardware watchpoint support
1505 Irix 5 configurations now support the use of hardware watchpoints.
1507 * Mips protocol "SYN garbage limit"
1509 When debugging a Mips target using the `target mips' protocol, you
1510 may set the number of characters that GDB will ignore by setting
1511 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1512 every character. The default value is 1050.
1514 * Recording and replaying remote debug sessions
1516 If you set `remotelogfile' to the name of a file, gdb will write to it
1517 a recording of a remote debug session. This recording may then be
1518 replayed back to gdb using "gdbreplay". See gdbserver/README for
1519 details. This is useful when you have a problem with GDB while doing
1520 remote debugging; you can make a recording of the session and send it
1521 to someone else, who can then recreate the problem.
1523 * Speedups for remote debugging
1525 GDB includes speedups for downloading and stepping MIPS systems using
1526 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1527 and more efficient S-record downloading.
1529 * Memory use reductions and statistics collection
1531 GDB now uses less memory and reports statistics about memory usage.
1532 Try the `maint print statistics' command, for example.
1534 *** Changes in GDB-4.15:
1536 * Psymtabs for XCOFF
1538 The symbol reader for AIX GDB now uses partial symbol tables. This
1539 can greatly improve startup time, especially for large executables.
1541 * Remote targets use caching
1543 Remote targets now use a data cache to speed up communication with the
1544 remote side. The data cache could lead to incorrect results because
1545 it doesn't know about volatile variables, thus making it impossible to
1546 debug targets which use memory mapped I/O devices. `set remotecache
1547 off' turns the the data cache off.
1549 * Remote targets may have threads
1551 The standard remote protocol now includes support for multiple threads
1552 in the target system, using new protocol commands 'H' and 'T'. See
1553 gdb/remote.c for details.
1557 If GDB is configured with `--enable-netrom', then it will include
1558 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1559 acts as though it is a bank of ROM on the target board, but you can
1560 write into it over the network. GDB's support consists only of
1561 support for fast loading into the emulated ROM; to debug, you must use
1562 another protocol, such as standard remote protocol. The usual
1563 sequence is something like
1565 target nrom <netrom-hostname>
1567 target remote <netrom-hostname>:1235
1571 GDB now includes support for the Apple Macintosh, as a host only. It
1572 may be run as either an MPW tool or as a standalone application, and
1573 it can debug through the serial port. All the usual GDB commands are
1574 available, but to the target command, you must supply "serial" as the
1575 device type instead of "/dev/ttyXX". See mpw-README in the main
1576 directory for more information on how to build. The MPW configuration
1577 scripts */mpw-config.in support only a few targets, and only the
1578 mips-idt-ecoff target has been tested.
1582 GDB configuration now uses autoconf. This is not user-visible,
1583 but does simplify configuration and building.
1587 GDB now supports hpux10.
1589 *** Changes in GDB-4.14:
1591 * New native configurations
1593 x86 FreeBSD i[345]86-*-freebsd
1594 x86 NetBSD i[345]86-*-netbsd
1595 NS32k NetBSD ns32k-*-netbsd
1596 Sparc NetBSD sparc-*-netbsd
1600 A29K VxWorks a29k-*-vxworks
1601 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1602 CPU32 EST-300 emulator m68*-*-est*
1603 PowerPC ELF powerpc-*-elf
1606 * Alpha OSF/1 support for procfs
1608 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1609 possible to attach to running processes. As the mounting of the /proc
1610 filesystem is optional on the Alpha, GDB automatically determines
1611 the availability of /proc during startup. This can lead to problems
1612 if /proc is unmounted after GDB has been started.
1614 * Arguments to user-defined commands
1616 User commands may accept up to 10 arguments separated by whitespace.
1617 Arguments are accessed within the user command via $arg0..$arg9. A
1620 print $arg0 + $arg1 + $arg2
1622 To execute the command use:
1625 Defines the command "adder" which prints the sum of its three arguments.
1626 Note the arguments are text substitutions, so they may reference variables,
1627 use complex expressions, or even perform inferior function calls.
1629 * New `if' and `while' commands
1631 This makes it possible to write more sophisticated user-defined
1632 commands. Both commands take a single argument, which is the
1633 expression to evaluate, and must be followed by the commands to
1634 execute, one per line, if the expression is nonzero, the list being
1635 terminated by the word `end'. The `if' command list may include an
1636 `else' word, which causes the following commands to be executed only
1637 if the expression is zero.
1639 * Fortran source language mode
1641 GDB now includes partial support for Fortran 77. It will recognize
1642 Fortran programs and can evaluate a subset of Fortran expressions, but
1643 variables and functions may not be handled correctly. GDB will work
1644 with G77, but does not yet know much about symbols emitted by other
1647 * Better HPUX support
1649 Most debugging facilities now work on dynamic executables for HPPAs
1650 running hpux9 or later. You can attach to running dynamically linked
1651 processes, but by default the dynamic libraries will be read-only, so
1652 for instance you won't be able to put breakpoints in them. To change
1653 that behavior do the following before running the program:
1659 This will cause the libraries to be mapped private and read-write.
1660 To revert to the normal behavior, do this:
1666 You cannot set breakpoints or examine data in the library until after
1667 the library is loaded if the function/data symbols do not have
1670 GDB can now also read debug symbols produced by the HP C compiler on
1671 HPPAs (sorry, no C++, Fortran or 68k support).
1673 * Target byte order now dynamically selectable
1675 You can choose which byte order to use with a target system, via the
1676 commands "set endian big" and "set endian little", and you can see the
1677 current setting by using "show endian". You can also give the command
1678 "set endian auto", in which case GDB will use the byte order
1679 associated with the executable. Currently, only embedded MIPS
1680 configurations support dynamic selection of target byte order.
1682 * New DOS host serial code
1684 This version uses DPMI interrupts to handle buffered I/O, so you
1685 no longer need to run asynctsr when debugging boards connected to
1688 *** Changes in GDB-4.13:
1690 * New "complete" command
1692 This lists all the possible completions for the rest of the line, if it
1693 were to be given as a command itself. This is intended for use by emacs.
1695 * Trailing space optional in prompt
1697 "set prompt" no longer adds a space for you after the prompt you set. This
1698 allows you to set a prompt which ends in a space or one that does not.
1700 * Breakpoint hit counts
1702 "info break" now displays a count of the number of times the breakpoint
1703 has been hit. This is especially useful in conjunction with "ignore"; you
1704 can ignore a large number of breakpoint hits, look at the breakpoint info
1705 to see how many times the breakpoint was hit, then run again, ignoring one
1706 less than that number, and this will get you quickly to the last hit of
1709 * Ability to stop printing at NULL character
1711 "set print null-stop" will cause GDB to stop printing the characters of
1712 an array when the first NULL is encountered. This is useful when large
1713 arrays actually contain only short strings.
1715 * Shared library breakpoints
1717 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1718 breakpoints in shared libraries before the executable is run.
1720 * Hardware watchpoints
1722 There is a new hardware breakpoint for the watch command for sparclite
1723 targets. See gdb/sparclite/hw_breakpoint.note.
1725 Hardware watchpoints are also now supported under GNU/Linux.
1729 Annotations have been added. These are for use with graphical interfaces,
1730 and are still experimental. Currently only gdba.el uses these.
1732 * Improved Irix 5 support
1734 GDB now works properly with Irix 5.2.
1736 * Improved HPPA support
1738 GDB now works properly with the latest GCC and GAS.
1740 * New native configurations
1742 Sequent PTX4 i[34]86-sequent-ptx4
1743 HPPA running OSF/1 hppa*-*-osf*
1744 Atari TT running SVR4 m68*-*-sysv4*
1745 RS/6000 LynxOS rs6000-*-lynxos*
1749 OS/9000 i[34]86-*-os9k
1750 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1753 * Hitachi SH7000 and E7000-PC ICE support
1755 There is now support for communicating with the Hitachi E7000-PC ICE.
1756 This is available automatically when GDB is configured for the SH.
1760 As usual, a variety of small fixes and improvements, both generic
1761 and configuration-specific. See the ChangeLog for more detail.
1763 *** Changes in GDB-4.12:
1765 * Irix 5 is now supported
1769 GDB-4.12 on the HPPA has a number of changes which make it unable
1770 to debug the output from the currently released versions of GCC and
1771 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1772 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1773 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1776 *** Changes in GDB-4.11:
1778 * User visible changes:
1782 The "set remotedebug" option is now consistent between the mips remote
1783 target, remote targets using the gdb-specific protocol, UDI (AMD's
1784 debug protocol for the 29k) and the 88k bug monitor. It is now an
1785 integer specifying a debug level (normally 0 or 1, but 2 means more
1786 debugging info for the mips target).
1788 * DEC Alpha native support
1790 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1791 debug info, but GDB works fairly well with the DEC compiler and should
1792 work with a future GCC release. See the README file for a few
1793 Alpha-specific notes.
1795 * Preliminary thread implementation
1797 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1799 * LynxOS native and target support for 386
1801 This release has been hosted on LynxOS 2.2, and also can be configured
1802 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1805 * Improvements in C++ mangling/demangling.
1807 This release has much better g++ debugging, specifically in name
1808 mangling/demangling, virtual function calls, print virtual table,
1809 call methods, ...etc.
1811 *** Changes in GDB-4.10:
1813 * User visible changes:
1815 Remote debugging using the GDB-specific (`target remote') protocol now
1816 supports the `load' command. This is only useful if you have some
1817 other way of getting the stub to the target system, and you can put it
1818 somewhere in memory where it won't get clobbered by the download.
1820 Filename completion now works.
1822 When run under emacs mode, the "info line" command now causes the
1823 arrow to point to the line specified. Also, "info line" prints
1824 addresses in symbolic form (as well as hex).
1826 All vxworks based targets now support a user settable option, called
1827 vxworks-timeout. This option represents the number of seconds gdb
1828 should wait for responses to rpc's. You might want to use this if
1829 your vxworks target is, perhaps, a slow software simulator or happens
1830 to be on the far side of a thin network line.
1834 This release contains support for using a DEC alpha as a GDB host for
1835 cross debugging. Native alpha debugging is not supported yet.
1838 *** Changes in GDB-4.9:
1842 This is the first GDB release which is accompanied by a matching testsuite.
1843 The testsuite requires installation of dejagnu, which should be available
1844 via ftp from most sites that carry GNU software.
1848 'Cfront' style demangling has had its name changed to 'ARM' style, to
1849 emphasize that it was written from the specifications in the C++ Annotated
1850 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1851 disclaimers, it still generated too much confusion with users attempting to
1852 use gdb with AT&T cfront.
1856 GDB now uses a standard remote interface to a simulator library.
1857 So far, the library contains simulators for the Zilog Z8001/2, the
1858 Hitachi H8/300, H8/500 and Super-H.
1860 * New targets supported
1862 H8/300 simulator h8300-hitachi-hms or h8300hms
1863 H8/500 simulator h8500-hitachi-hms or h8500hms
1864 SH simulator sh-hitachi-hms or sh
1865 Z8000 simulator z8k-zilog-none or z8ksim
1866 IDT MIPS board over serial line mips-idt-ecoff
1868 Cross-debugging to GO32 targets is supported. It requires a custom
1869 version of the i386-stub.c module which is integrated with the
1870 GO32 memory extender.
1872 * New remote protocols
1874 MIPS remote debugging protocol.
1876 * New source languages supported
1878 This version includes preliminary support for Chill, a Pascal like language
1879 used by telecommunications companies. Chill support is also being integrated
1880 into the GNU compiler, but we don't know when it will be publically available.
1883 *** Changes in GDB-4.8:
1885 * HP Precision Architecture supported
1887 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1888 version of this support was available as a set of patches from the
1889 University of Utah. GDB does not support debugging of programs
1890 compiled with the HP compiler, because HP will not document their file
1891 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1892 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1894 Many problems in the preliminary version have been fixed.
1896 * Faster and better demangling
1898 We have improved template demangling and fixed numerous bugs in the GNU style
1899 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1900 character types (wchar_t) are now supported. Demangling of each symbol is now
1901 only done once, and is cached when the symbol table for a file is read in.
1902 This results in a small increase in memory usage for C programs, a moderate
1903 increase in memory usage for C++ programs, and a fantastic speedup in
1906 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1907 from the specifications in the Annotated Reference Manual, which AT&T's
1908 compiler does not actually implement.
1910 * G++ multiple inheritance compiler problem
1912 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1913 inheritance lattices was reworked to properly discover ambiguities. We
1914 recently found an example which causes this new algorithm to fail in a
1915 very subtle way, producing bad debug information for those classes.
1916 The file 'gcc.patch' (in this directory) can be applied to gcc to
1917 circumvent the problem. A future GCC release will contain a complete
1920 The previous G++ debug info problem (mentioned below for the gdb-4.7
1921 release) is fixed in gcc version 2.3.2.
1923 * Improved configure script
1925 The `configure' script will now attempt to guess your system type if
1926 you don't supply a host system type. The old scheme of supplying a
1927 host system triplet is preferable over using this. All the magic is
1928 done in the new `config.guess' script. Examine it for details.
1930 We have also brought our configure script much more in line with the FSF's
1931 version. It now supports the --with-xxx options. In particular,
1932 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1933 The resulting GDB will not be able to read arbitrary object file formats --
1934 only the format ``expected'' to be used on the configured target system.
1935 We hope to make this the default in a future release.
1937 * Documentation improvements
1939 There's new internal documentation on how to modify GDB, and how to
1940 produce clean changes to the code. We implore people to read it
1941 before submitting changes.
1943 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1944 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1945 `info' files are also provided. To build `info' files from scratch,
1946 you will need the latest `makeinfo' release, which will be available in
1947 a future texinfo-X.Y release.
1949 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1950 We're not sure exactly which versions have this problem, but it has
1951 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1952 or better. If that isn't possible, there is a patch in
1953 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1954 around this problem.
1958 GDB now supports array constants that can be used in expressions typed in by
1959 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1960 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1963 The new directory `gdb/sparclite' contains a program that demonstrates
1964 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1966 * New native hosts supported
1968 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1969 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1971 * New targets supported
1973 AMD 29k family via UDI a29k-amd-udi or udi29k
1975 * New file formats supported
1977 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1978 HPUX core files, and SCO 3.2v2 core files.
1982 Attaching to processes now works again; thanks for the many bug reports.
1984 We have also stomped on a bunch of core dumps caused by
1985 printf_filtered("%s") problems.
1987 We eliminated a copyright problem on the rpc and ptrace header files
1988 for VxWorks, which was discovered at the last minute during the 4.7
1989 release. You should now be able to build a VxWorks GDB.
1991 You can now interrupt gdb while an attached process is running. This
1992 will cause the attached process to stop, and give control back to GDB.
1994 We fixed problems caused by using too many file descriptors
1995 for reading symbols from object files and libraries. This was
1996 especially a problem for programs that used many (~100) shared
1999 The `step' command now only enters a subroutine if there is line number
2000 information for the subroutine. Otherwise it acts like the `next'
2001 command. Previously, `step' would enter subroutines if there was
2002 any debugging information about the routine. This avoids problems
2003 when using `cc -g1' on MIPS machines.
2005 * Internal improvements
2007 GDB's internal interfaces have been improved to make it easier to support
2008 debugging of multiple languages in the future.
2010 GDB now uses a common structure for symbol information internally.
2011 Minimal symbols (derived from linkage symbols in object files), partial
2012 symbols (from a quick scan of debug information), and full symbols
2013 contain a common subset of information, making it easier to write
2014 shared code that handles any of them.
2016 * New command line options
2018 We now accept --silent as an alias for --quiet.
2022 The memory-mapped-malloc library is now licensed under the GNU Library
2023 General Public License.
2025 *** Changes in GDB-4.7:
2027 * Host/native/target split
2029 GDB has had some major internal surgery to untangle the support for
2030 hosts and remote targets. Now, when you configure GDB for a remote
2031 target, it will no longer load in all of the support for debugging
2032 local programs on the host. When fully completed and tested, this will
2033 ensure that arbitrary host/target combinations are possible.
2035 The primary conceptual shift is to separate the non-portable code in
2036 GDB into three categories. Host specific code is required any time GDB
2037 is compiled on that host, regardless of the target. Target specific
2038 code relates to the peculiarities of the target, but can be compiled on
2039 any host. Native specific code is everything else: it can only be
2040 built when the host and target are the same system. Child process
2041 handling and core file support are two common `native' examples.
2043 GDB's use of /proc for controlling Unix child processes is now cleaner.
2044 It has been split out into a single module under the `target_ops' vector,
2045 plus two native-dependent functions for each system that uses /proc.
2047 * New hosts supported
2049 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
2050 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2051 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
2053 * New targets supported
2055 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2056 68030 and CPU32 m68030-*-*, m68332-*-*
2058 * New native hosts supported
2060 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
2061 (386bsd is not well tested yet)
2062 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
2064 * New file formats supported
2066 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
2067 supports reading of `a.out.adobe' object files, which are an a.out
2068 format extended with minimal information about multiple sections.
2072 `show copying' is the same as the old `info copying'.
2073 `show warranty' is the same as `info warrantee'.
2074 These were renamed for consistency. The old commands continue to work.
2076 `info handle' is a new alias for `info signals'.
2078 You can now define pre-command hooks, which attach arbitrary command
2079 scripts to any command. The commands in the hook will be executed
2080 prior to the user's command. You can also create a hook which will be
2081 executed whenever the program stops. See gdb.texinfo.
2085 We now deal with Cfront style name mangling, and can even extract type
2086 info from mangled symbols. GDB can automatically figure out which
2087 symbol mangling style your C++ compiler uses.
2089 Calling of methods and virtual functions has been improved as well.
2093 The crash that occured when debugging Sun Ansi-C compiled binaries is
2094 fixed. This was due to mishandling of the extra N_SO stabs output
2097 We also finally got Ultrix 4.2 running in house, and fixed core file
2098 support, with help from a dozen people on the net.
2100 John M. Farrell discovered that the reason that single-stepping was so
2101 slow on all of the Mips based platforms (primarily SGI and DEC) was
2102 that we were trying to demangle and lookup a symbol used for internal
2103 purposes on every instruction that was being stepped through. Changing
2104 the name of that symbol so that it couldn't be mistaken for a C++
2105 mangled symbol sped things up a great deal.
2107 Rich Pixley sped up symbol lookups in general by getting much smarter
2108 about when C++ symbol mangling is necessary. This should make symbol
2109 completion (TAB on the command line) much faster. It's not as fast as
2110 we'd like, but it's significantly faster than gdb-4.6.
2114 A new user controllable variable 'call_scratch_address' can
2115 specify the location of a scratch area to be used when GDB
2116 calls a function in the target. This is necessary because the
2117 usual method of putting the scratch area on the stack does not work
2118 in systems that have separate instruction and data spaces.
2120 We integrated changes to support the 29k UDI (Universal Debugger
2121 Interface), but discovered at the last minute that we didn't have all
2122 of the appropriate copyright paperwork. We are working with AMD to
2123 resolve this, and hope to have it available soon.
2127 We have sped up the remote serial line protocol, especially for targets
2128 with lots of registers. It now supports a new `expedited status' ('T')
2129 message which can be used in place of the existing 'S' status message.
2130 This allows the remote stub to send only the registers that GDB
2131 needs to make a quick decision about single-stepping or conditional
2132 breakpoints, eliminating the need to fetch the entire register set for
2133 each instruction being stepped through.
2135 The GDB remote serial protocol now implements a write-through cache for
2136 registers, only re-reading the registers if the target has run.
2138 There is also a new remote serial stub for SPARC processors. You can
2139 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
2140 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
2141 processor with a serial port.
2145 Configure.in files have become much easier to read and modify. A new
2146 `table driven' format makes it more obvious what configurations are
2147 supported, and what files each one uses.
2151 There is a new opcodes library which will eventually contain all of the
2152 disassembly routines and opcode tables. At present, it only contains
2153 Sparc and Z8000 routines. This will allow the assembler, debugger, and
2154 disassembler (binutils/objdump) to share these routines.
2156 The libiberty library is now copylefted under the GNU Library General
2157 Public License. This allows more liberal use, and was done so libg++
2158 can use it. This makes no difference to GDB, since the Library License
2159 grants all the rights from the General Public License.
2163 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
2164 reference to the stabs symbol info used by the debugger. It is (as far
2165 as we know) the only published document on this fascinating topic. We
2166 encourage you to read it, compare it to the stabs information on your
2167 system, and send improvements on the document in general (to
2168 bug-gdb@prep.ai.mit.edu).
2170 And, of course, many bugs have been fixed.
2173 *** Changes in GDB-4.6:
2175 * Better support for C++ function names
2177 GDB now accepts as input the "demangled form" of C++ overloaded function
2178 names and member function names, and can do command completion on such names
2179 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
2180 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
2181 Make use of command completion, it is your friend.
2183 GDB also now accepts a variety of C++ mangled symbol formats. They are
2184 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
2185 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
2186 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
2187 for the list of formats.
2189 * G++ symbol mangling problem
2191 Recent versions of gcc have a bug in how they emit debugging information for
2192 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
2193 directory) can be applied to gcc to fix the problem. Alternatively, if you
2194 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
2195 usual symptom is difficulty with setting breakpoints on methods. GDB complains
2196 about the method being non-existent. (We believe that version 2.2.2 of GCC has
2199 * New 'maintenance' command
2201 All of the commands related to hacking GDB internals have been moved out of
2202 the main command set, and now live behind the 'maintenance' command. This
2203 can also be abbreviated as 'mt'. The following changes were made:
2205 dump-me -> maintenance dump-me
2206 info all-breakpoints -> maintenance info breakpoints
2207 printmsyms -> maintenance print msyms
2208 printobjfiles -> maintenance print objfiles
2209 printpsyms -> maintenance print psymbols
2210 printsyms -> maintenance print symbols
2212 The following commands are new:
2214 maintenance demangle Call internal GDB demangler routine to
2215 demangle a C++ link name and prints the result.
2216 maintenance print type Print a type chain for a given symbol
2218 * Change to .gdbinit file processing
2220 We now read the $HOME/.gdbinit file before processing the argv arguments
2221 (e.g. reading symbol files or core files). This allows global parameters to
2222 be set, which will apply during the symbol reading. The ./.gdbinit is still
2223 read after argv processing.
2225 * New hosts supported
2227 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
2229 GNU/Linux support i386-unknown-linux or linux
2231 We are also including code to support the HP/PA running BSD and HPUX. This
2232 is almost guaranteed not to work, as we didn't have time to test or build it
2233 for this release. We are including it so that the more adventurous (or
2234 masochistic) of you can play with it. We also had major problems with the
2235 fact that the compiler that we got from HP doesn't support the -g option.
2238 * New targets supported
2240 Hitachi H8/300 h8300-hitachi-hms or h8300hms
2242 * More smarts about finding #include files
2244 GDB now remembers the compilation directory for all include files, and for
2245 all files from which C is generated (like yacc and lex sources). This
2246 greatly improves GDB's ability to find yacc/lex sources, and include files,
2247 especially if you are debugging your program from a directory different from
2248 the one that contains your sources.
2250 We also fixed a bug which caused difficulty with listing and setting
2251 breakpoints in include files which contain C code. (In the past, you had to
2252 try twice in order to list an include file that you hadn't looked at before.)
2254 * Interesting infernals change
2256 GDB now deals with arbitrary numbers of sections, where the symbols for each
2257 section must be relocated relative to that section's landing place in the
2258 target's address space. This work was needed to support ELF with embedded
2259 stabs used by Solaris-2.0.
2261 * Bug fixes (of course!)
2263 There have been loads of fixes for the following things:
2264 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2265 i960, stabs, DOS(GO32), procfs, etc...
2267 See the ChangeLog for details.
2269 *** Changes in GDB-4.5:
2271 * New machines supported (host and target)
2273 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2275 SGI Irix-4.x mips-sgi-irix4 or iris4
2277 * New malloc package
2279 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2280 Mmalloc is capable of handling mutiple heaps of memory. It is also
2281 capable of saving a heap to a file, and then mapping it back in later.
2282 This can be used to greatly speedup the startup of GDB by using a
2283 pre-parsed symbol table which lives in a mmalloc managed heap. For
2284 more details, please read mmalloc/mmalloc.texi.
2288 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2289 'help info proc' for details.
2291 * MIPS ecoff symbol table format
2293 The code that reads MIPS symbol table format is now supported on all hosts.
2294 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2297 * File name changes for MS-DOS
2299 Many files in the config directories have been renamed to make it easier to
2300 support GDB on MS-DOSe systems (which have very restrictive file name
2301 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2302 environment) is close to working but has some remaining problems. Note
2303 that debugging of DOS programs is not supported, due to limitations
2304 in the ``operating system'', but it can be used to host cross-debugging.
2306 * Cross byte order fixes
2308 Many fixes have been made to support cross debugging of Sparc and MIPS
2309 targets from hosts whose byte order differs.
2311 * New -mapped and -readnow options
2313 If memory-mapped files are available on your system through the 'mmap'
2314 system call, you can use the -mapped option on the `file' or
2315 `symbol-file' commands to cause GDB to write the symbols from your
2316 program into a reusable file. If the program you are debugging is
2317 called `/path/fred', the mapped symbol file will be `./fred.syms'.
2318 Future GDB debugging sessions will notice the presence of this file,
2319 and will quickly map in symbol information from it, rather than reading
2320 the symbol table from the executable program. Using the '-mapped'
2321 option in a GDB `file' or `symbol-file' command has the same effect as
2322 starting GDB with the '-mapped' command-line option.
2324 You can cause GDB to read the entire symbol table immediately by using
2325 the '-readnow' option with any of the commands that load symbol table
2326 information (or on the GDB command line). This makes the command
2327 slower, but makes future operations faster.
2329 The -mapped and -readnow options are typically combined in order to
2330 build a `fred.syms' file that contains complete symbol information.
2331 A simple GDB invocation to do nothing but build a `.syms' file for future
2334 gdb -batch -nx -mapped -readnow programname
2336 The `.syms' file is specific to the host machine on which GDB is run.
2337 It holds an exact image of GDB's internal symbol table. It cannot be
2338 shared across multiple host platforms.
2340 * longjmp() handling
2342 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2343 siglongjmp() without losing control. This feature has not yet been ported to
2344 all systems. It currently works on many 386 platforms, all MIPS-based
2345 platforms (SGI, DECstation, etc), and Sun3/4.
2349 Preliminary work has been put in to support the new Solaris OS from Sun. At
2350 this time, it can control and debug processes, but it is not capable of
2355 As always, many many bug fixes. The major areas were with g++, and mipsread.
2356 People using the MIPS-based platforms should experience fewer mysterious
2357 crashes and trashed symbol tables.
2359 *** Changes in GDB-4.4:
2361 * New machines supported (host and target)
2363 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2365 BSD Reno on Vax vax-dec-bsd
2366 Ultrix on Vax vax-dec-ultrix
2368 * New machines supported (target)
2370 AMD 29000 embedded, using EBMON a29k-none-none
2374 GDB continues to improve its handling of C++. `References' work better.
2375 The demangler has also been improved, and now deals with symbols mangled as
2376 per the Annotated C++ Reference Guide.
2378 GDB also now handles `stabs' symbol information embedded in MIPS
2379 `ecoff' symbol tables. Since the ecoff format was not easily
2380 extensible to handle new languages such as C++, this appeared to be a
2381 good way to put C++ debugging info into MIPS binaries. This option
2382 will be supported in the GNU C compiler, version 2, when it is
2385 * New features for SVR4
2387 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2388 shared libraries. Debugging dynamically linked programs should present
2389 only minor differences from debugging statically linked programs.
2391 The `info proc' command will print out information about any process
2392 on an SVR4 system (including the one you are debugging). At the moment,
2393 it prints the address mappings of the process.
2395 If you bring up GDB on another SVR4 system, please send mail to
2396 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2398 * Better dynamic linking support in SunOS
2400 Reading symbols from shared libraries which contain debugging symbols
2401 now works properly. However, there remain issues such as automatic
2402 skipping of `transfer vector' code during function calls, which
2403 make it harder to debug code in a shared library, than to debug the
2404 same code linked statically.
2408 GDB is now using the latest `getopt' routines from the FSF. This
2409 version accepts the -- prefix for options with long names. GDB will
2410 continue to accept the old forms (-option and +option) as well.
2411 Various single letter abbreviations for options have been explicity
2412 added to the option table so that they won't get overshadowed in the
2413 future by other options that begin with the same letter.
2417 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2418 Many assorted bugs have been handled. Many more remain to be handled.
2419 See the various ChangeLog files (primarily in gdb and bfd) for details.
2422 *** Changes in GDB-4.3:
2424 * New machines supported (host and target)
2426 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2427 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2428 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2430 * Almost SCO Unix support
2432 We had hoped to support:
2433 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2434 (except for core file support), but we discovered very late in the release
2435 that it has problems with process groups that render gdb unusable. Sorry
2436 about that. I encourage people to fix it and post the fixes.
2438 * Preliminary ELF and DWARF support
2440 GDB can read ELF object files on System V Release 4, and can handle
2441 debugging records for C, in DWARF format, in ELF files. This support
2442 is preliminary. If you bring up GDB on another SVR4 system, please
2443 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2448 GDB now uses the latest `readline' library. One user-visible change
2449 is that two tabs will list possible command completions, which previously
2450 required typing M-? (meta-question mark, or ESC ?).
2454 The `stepi' bug that many of you noticed has been squashed.
2455 Many bugs in C++ have been handled. Many more remain to be handled.
2456 See the various ChangeLog files (primarily in gdb and bfd) for details.
2458 * State of the MIPS world (in case you wondered):
2460 GDB can understand the symbol tables emitted by the compilers
2461 supplied by most vendors of MIPS-based machines, including DEC. These
2462 symbol tables are in a format that essentially nobody else uses.
2464 Some versions of gcc come with an assembler post-processor called
2465 mips-tfile. This program is required if you want to do source-level
2466 debugging of gcc-compiled programs. I believe FSF does not ship
2467 mips-tfile with gcc version 1, but it will eventually come with gcc
2470 Debugging of g++ output remains a problem. g++ version 1.xx does not
2471 really support it at all. (If you're lucky, you should be able to get
2472 line numbers and stack traces to work, but no parameters or local
2473 variables.) With some work it should be possible to improve the
2476 When gcc version 2 is released, you will have somewhat better luck.
2477 However, even then you will get confusing results for inheritance and
2480 We will eventually provide full debugging of g++ output on
2481 DECstations. This will probably involve some kind of stabs-in-ecoff
2482 encapulation, but the details have not been worked out yet.
2485 *** Changes in GDB-4.2:
2487 * Improved configuration
2489 Only one copy of `configure' exists now, and it is not self-modifying.
2490 Porting BFD is simpler.
2494 The `step' and `next' commands now only stop at the first instruction
2495 of a source line. This prevents the multiple stops that used to occur
2496 in switch statements, for-loops, etc. `Step' continues to stop if a
2497 function that has debugging information is called within the line.
2501 Lots of small bugs fixed. More remain.
2503 * New host supported (not target)
2505 Intel 386 PC clone running Mach i386-none-mach
2508 *** Changes in GDB-4.1:
2510 * Multiple source language support
2512 GDB now has internal scaffolding to handle several source languages.
2513 It determines the type of each source file from its filename extension,
2514 and will switch expression parsing and number formatting to match the
2515 language of the function in the currently selected stack frame.
2516 You can also specifically set the language to be used, with
2517 `set language c' or `set language modula-2'.
2521 GDB now has preliminary support for the GNU Modula-2 compiler,
2522 currently under development at the State University of New York at
2523 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2524 continue through the fall of 1991 and into 1992.
2526 Other Modula-2 compilers are currently not supported, and attempting to
2527 debug programs compiled with them will likely result in an error as the
2528 symbol table is read. Feel free to work on it, though!
2530 There are hooks in GDB for strict type checking and range checking,
2531 in the `Modula-2 philosophy', but they do not currently work.
2535 GDB can now write to executable and core files (e.g. patch
2536 a variable's value). You must turn this switch on, specify
2537 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2538 by assigning a new value to a variable. Modifications take
2541 * Automatic SunOS shared library reading
2543 When you run your program, GDB automatically determines where its
2544 shared libraries (if any) have been loaded, and reads their symbols.
2545 The `share' command is no longer needed. This also works when
2546 examining core files.
2550 You can specify the number of lines that the `list' command shows.
2553 * New machines supported (host and target)
2555 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2556 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2557 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2559 * New hosts supported (not targets)
2561 IBM RT/PC: romp-ibm-aix or rtpc
2563 * New targets supported (not hosts)
2565 AMD 29000 embedded with COFF a29k-none-coff
2566 AMD 29000 embedded with a.out a29k-none-aout
2567 Ultracomputer remote kernel debug a29k-nyu-kern
2569 * New remote interfaces
2575 *** Changes in GDB-4.0:
2579 Wide output is wrapped at good places to make the output more readable.
2581 Gdb now supports cross-debugging from a host machine of one type to a
2582 target machine of another type. Communication with the target system
2583 is over serial lines. The ``target'' command handles connecting to the
2584 remote system; the ``load'' command will download a program into the
2585 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2586 also supports debugging of realtime processes running under VxWorks,
2587 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2588 stub on the target system.
2590 New CPUs supported include the AMD 29000 and Intel 960.
2592 GDB now reads object files and symbol tables via a ``binary file''
2593 library, which allows a single copy of GDB to debug programs of multiple
2594 object file types such as a.out and coff.
2596 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2597 refcard.dvi and refcard.ps are available to format it).
2600 * Control-Variable user interface simplified
2602 All variables that control the operation of the debugger can be set
2603 by the ``set'' command, and displayed by the ``show'' command.
2605 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2606 ``Show prompt'' produces the response:
2607 Gdb's prompt is new-gdb=>.
2609 What follows are the NEW set commands. The command ``help set'' will
2610 print a complete list of old and new set commands. ``help set FOO''
2611 will give a longer description of the variable FOO. ``show'' will show
2612 all of the variable descriptions and their current settings.
2614 confirm on/off: Enables warning questions for operations that are
2615 hard to recover from, e.g. rerunning the program while
2616 it is already running. Default is ON.
2618 editing on/off: Enables EMACS style command line editing
2619 of input. Previous lines can be recalled with
2620 control-P, the current line can be edited with control-B,
2621 you can search for commands with control-R, etc.
2624 history filename NAME: NAME is where the gdb command history
2625 will be stored. The default is .gdb_history,
2626 or the value of the environment variable
2629 history size N: The size, in commands, of the command history. The
2630 default is 256, or the value of the environment variable
2633 history save on/off: If this value is set to ON, the history file will
2634 be saved after exiting gdb. If set to OFF, the
2635 file will not be saved. The default is OFF.
2637 history expansion on/off: If this value is set to ON, then csh-like
2638 history expansion will be performed on
2639 command line input. The default is OFF.
2641 radix N: Sets the default radix for input and output. It can be set
2642 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2643 in the current radix, so "set radix 10" is always a no-op.
2645 height N: This integer value is the number of lines on a page. Default
2646 is 24, the current `stty rows'' setting, or the ``li#''
2647 setting from the termcap entry matching the environment
2650 width N: This integer value is the number of characters on a line.
2651 Default is 80, the current `stty cols'' setting, or the ``co#''
2652 setting from the termcap entry matching the environment
2655 Note: ``set screensize'' is obsolete. Use ``set height'' and
2656 ``set width'' instead.
2658 print address on/off: Print memory addresses in various command displays,
2659 such as stack traces and structure values. Gdb looks
2660 more ``symbolic'' if you turn this off; it looks more
2661 ``machine level'' with it on. Default is ON.
2663 print array on/off: Prettyprint arrays. New convenient format! Default
2666 print demangle on/off: Print C++ symbols in "source" form if on,
2669 print asm-demangle on/off: Same, for assembler level printouts
2672 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2675 * Support for Epoch Environment.
2677 The epoch environment is a version of Emacs v18 with windowing. One
2678 new command, ``inspect'', is identical to ``print'', except that if you
2679 are running in the epoch environment, the value is printed in its own
2683 * Support for Shared Libraries
2685 GDB can now debug programs and core files that use SunOS shared libraries.
2686 Symbols from a shared library cannot be referenced
2687 before the shared library has been linked with the program (this
2688 happens after you type ``run'' and before the function main() is entered).
2689 At any time after this linking (including when examining core files
2690 from dynamically linked programs), gdb reads the symbols from each
2691 shared library when you type the ``sharedlibrary'' command.
2692 It can be abbreviated ``share''.
2694 sharedlibrary REGEXP: Load shared object library symbols for files
2695 matching a unix regular expression. No argument
2696 indicates to load symbols for all shared libraries.
2698 info sharedlibrary: Status of loaded shared libraries.
2703 A watchpoint stops execution of a program whenever the value of an
2704 expression changes. Checking for this slows down execution
2705 tremendously whenever you are in the scope of the expression, but is
2706 quite useful for catching tough ``bit-spreader'' or pointer misuse
2707 problems. Some machines such as the 386 have hardware for doing this
2708 more quickly, and future versions of gdb will use this hardware.
2710 watch EXP: Set a watchpoint (breakpoint) for an expression.
2712 info watchpoints: Information about your watchpoints.
2714 delete N: Deletes watchpoint number N (same as breakpoints).
2715 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2716 enable N: Re-enables watchpoint number N (same as breakpoints).
2719 * C++ multiple inheritance
2721 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2724 * C++ exception handling
2726 Gdb now supports limited C++ exception handling. Besides the existing
2727 ability to breakpoint on an exception handler, gdb can breakpoint on
2728 the raising of an exception (before the stack is peeled back to the
2731 catch FOO: If there is a FOO exception handler in the dynamic scope,
2732 set a breakpoint to catch exceptions which may be raised there.
2733 Multiple exceptions (``catch foo bar baz'') may be caught.
2735 info catch: Lists all exceptions which may be caught in the
2736 current stack frame.
2739 * Minor command changes
2741 The command ``call func (arg, arg, ...)'' now acts like the print
2742 command, except it does not print or save a value if the function's result
2743 is void. This is similar to dbx usage.
2745 The ``up'' and ``down'' commands now always print the frame they end up
2746 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2747 frames without printing.
2749 * New directory command
2751 'dir' now adds directories to the FRONT of the source search path.
2752 The path starts off empty. Source files that contain debug information
2753 about the directory in which they were compiled can be found even
2754 with an empty path; Sun CC and GCC include this information. If GDB can't
2755 find your source file in the current directory, type "dir .".
2757 * Configuring GDB for compilation
2759 For normal use, type ``./configure host''. See README or gdb.texinfo
2762 GDB now handles cross debugging. If you are remotely debugging between
2763 two different machines, type ``./configure host -target=targ''.
2764 Host is the machine where GDB will run; targ is the machine
2765 where the program that you are debugging will run.