1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.1:
6 * New ``start'' command.
8 This command runs the program until the begining of the main procedure.
10 * Signal trampoline code overhauled
12 Many generic problems with GDB's signal handling code have been fixed.
13 These include: backtraces through non-contiguous stacks; recognition
14 of sa_sigaction signal trampolines; backtrace from a NULL pointer
15 call; backtrace through a signal trampoline; step into and out of
16 signal handlers; and single-stepping in the signal trampoline.
18 These fixes were tested on i386 GNU/Linux systems that include a 2.4
21 * Cygwin support for DWARF 2 added.
23 * Fixed build problem on IRIX 5
25 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
26 wasn't able to compile compile on an IRIX 5 system.
28 * Added execute permission to gdb/gdbserver/configure
30 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
31 permission. This bug would cause configure to fail on a number of
32 systems (Solaris, IRIX). Ref: server/519.
34 * New native configurations
36 OpenBSD/m68k m68*-*-openbsd*
37 OpenBSD/m88k m88*-*-openbsd*
38 OpenBSD/powerpc powerpc-*-openbsd*
39 NetBSD/vax vax-*-netbsd*
40 OpenBSD/vax vax-*-openbsd*
42 * REMOVED configurations and files
44 Sun 3, running SunOS 3 m68*-*-sunos3*
45 Sun 3, running SunOS 4 m68*-*-sunos4*
46 Sun 2, running SunOS 3 m68000-*-sunos3*
47 Sun 2, running SunOS 4 m68000-*-sunos4*
48 Motorola 680x0 running LynxOS m68*-*-lynxos*
49 AT&T 3b1/Unix pc m68*-att-*
50 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
51 decstation mips-dec-* mips-little-*
52 riscos mips-*-riscos* mips-*-sysv*
54 sysv mips*-*-sysv4* (IRIX 5/6 not included)
56 *** Changes in GDB 6.1:
58 * Removed --with-mmalloc
60 Support for the mmalloc memory manager has been removed, as it
61 conflicted with the internal gdb byte cache.
63 * Changes in AMD64 configurations
65 The AMD64 target now includes the %cs and %ss registers. As a result
66 the AMD64 remote protocol has changed; this affects the floating-point
67 and SSE registers. If you rely on those registers for your debugging,
68 you should upgrade gdbserver on the remote side.
70 * Revised SPARC target
72 The SPARC target has been completely revised, incorporating the
73 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
74 support for LynxOS and SunOS 4 has been dropped. Calling functions
75 from within GDB on operating systems with a non-executable stack
76 (Solaris, OpenBSD) now works.
80 GDB has a new C++ demangler which does a better job on the mangled
81 names generated by current versions of g++. It also runs faster, so
82 with this and other changes gdb should now start faster on large C++
85 * DWARF 2 Location Expressions
87 GDB support for location expressions has been extended to support function
88 arguments and frame bases. Older versions of GDB could crash when they
91 * C++ nested types and namespaces
93 GDB's support for nested types and namespaces in C++ has been
94 improved, especially if you use the DWARF 2 debugging format. (This
95 is the default for recent versions of GCC on most platforms.)
96 Specifically, if you have a class "Inner" defined within a class or
97 namespace "Outer", then GDB realizes that the class's name is
98 "Outer::Inner", not simply "Inner". This should greatly reduce the
99 frequency of complaints about not finding RTTI symbols. In addition,
100 if you are stopped at inside of a function defined within a namespace,
101 GDB modifies its name lookup accordingly.
103 * New native configurations
105 NetBSD/amd64 x86_64-*-netbsd*
106 OpenBSD/amd64 x86_64-*-openbsd*
107 OpenBSD/alpha alpha*-*-openbsd*
108 OpenBSD/sparc sparc-*-openbsd*
109 OpenBSD/sparc64 sparc64-*-openbsd*
111 * New debugging protocols
113 M32R with SDI protocol m32r-*-elf*
115 * "set prompt-escape-char" command deleted.
117 The command "set prompt-escape-char" has been deleted. This command,
118 and its very obscure effet on GDB's prompt, was never documented,
119 tested, nor mentioned in the NEWS file.
121 * OBSOLETE configurations and files
123 Configurations that have been declared obsolete in this release have
124 been commented out. Unless there is activity to revive these
125 configurations, the next release of GDB will have their sources
128 Sun 3, running SunOS 3 m68*-*-sunos3*
129 Sun 3, running SunOS 4 m68*-*-sunos4*
130 Sun 2, running SunOS 3 m68000-*-sunos3*
131 Sun 2, running SunOS 4 m68000-*-sunos4*
132 Motorola 680x0 running LynxOS m68*-*-lynxos*
133 AT&T 3b1/Unix pc m68*-att-*
134 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
135 decstation mips-dec-* mips-little-*
136 riscos mips-*-riscos* mips-*-sysv*
138 sysv mips*-*-sysv4* (IRIX 5/6 not included)
140 * REMOVED configurations and files
142 SGI Irix-4.x mips-sgi-irix4 or iris4
143 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
144 Z8000 simulator z8k-zilog-none or z8ksim
145 Matsushita MN10200 w/simulator mn10200-*-*
146 H8/500 simulator h8500-hitachi-hms or h8500hms
147 HP/PA running BSD hppa*-*-bsd*
148 HP/PA running OSF/1 hppa*-*-osf*
149 HP/PA Pro target hppa*-*-pro*
150 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
151 386BSD i[3456]86-*-bsd*
152 Sequent family i[3456]86-sequent-sysv4*
153 i[3456]86-sequent-sysv*
154 i[3456]86-sequent-bsd*
155 SPARC running LynxOS sparc-*-lynxos*
156 SPARC running SunOS 4 sparc-*-sunos4*
157 Tsqware Sparclet sparclet-*-*
158 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
160 *** Changes in GDB 6.0:
164 Support for debugging the Objective-C programming language has been
167 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
169 DWARF 2's Call Frame Information makes available compiler generated
170 information that more exactly describes the program's run-time stack.
171 By using this information, GDB is able to provide more robust stack
174 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
175 have been updated to use a new backtrace mechanism which includes
180 GDB's remote protocol has been extended to include support for hosted
181 file I/O (where the remote target uses GDB's file system). See GDB's
182 remote protocol documentation for details.
184 * All targets using the new architecture framework.
186 All of GDB's targets have been updated to use the new internal
187 architecture framework. The way is now open for future GDB releases
188 to include cross-architecture native debugging support (i386 on amd64,
191 * GNU/Linux's Thread Local Storage (TLS)
193 GDB now includes support for for the GNU/Linux implementation of
194 per-thread variables.
196 * GNU/Linux's Native POSIX Thread Library (NPTL)
198 GDB's thread code has been updated to work with either the new
199 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
201 * Separate debug info.
203 GDB, in conjunction with BINUTILS, now supports a mechanism for
204 automatically loading debug information from a separate file. Instead
205 of shipping full debug and non-debug versions of system libraries,
206 system integrators can now instead ship just the stripped libraries
207 and optional debug files.
209 * DWARF 2 Location Expressions
211 DWARF 2 Location Expressions allow the compiler to more completely
212 describe the location of variables (even in optimized code) to the
215 GDB now includes preliminary support for location expressions (support
216 for DW_OP_piece is still missing).
220 A number of long standing bugs that caused GDB to die while starting a
221 Java application have been fixed. GDB's Java support is now
222 considered "useable".
224 * GNU/Linux support for fork, vfork, and exec.
226 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
227 commands are now implemented for GNU/Linux. They require a 2.5.x or later
230 * GDB supports logging output to a file
232 There are two new commands, "set logging" and "show logging", which can be
233 used to capture GDB's output to a file.
235 * The meaning of "detach" has changed for gdbserver
237 The "detach" command will now resume the application, as documented. To
238 disconnect from gdbserver and leave it stopped, use the new "disconnect"
241 * d10v, m68hc11 `regs' command deprecated
243 The `info registers' command has been updated so that it displays the
244 registers using a format identical to the old `regs' command.
248 A new command, "maint set profile on/off", has been added. This command can
249 be used to enable or disable profiling while running GDB, to profile a
250 session or a set of commands. In addition there is a new configure switch,
251 "--enable-profiling", which will cause GDB to be compiled with profiling
252 data, for more informative profiling results.
254 * Default MI syntax changed to "mi2".
256 The default MI (machine interface) syntax, enabled by the command line
257 option "-i=mi", has been changed to "mi2". The previous MI syntax,
258 "mi1", can be enabled by specifying the option "-i=mi1".
260 Support for the original "mi0" syntax (included in GDB 5.0) has been
263 Fix for gdb/192: removed extraneous space when displaying frame level.
264 Fix for gdb/672: update changelist is now output in mi list format.
265 Fix for gdb/702: a -var-assign that updates the value now shows up
266 in a subsequent -var-update.
268 * New native configurations.
270 FreeBSD/amd64 x86_64-*-freebsd*
272 * Multi-arched targets.
274 HP/PA HPUX11 hppa*-*-hpux*
275 Renesas M32R/D w/simulator m32r-*-elf*
277 * OBSOLETE configurations and files
279 Configurations that have been declared obsolete in this release have
280 been commented out. Unless there is activity to revive these
281 configurations, the next release of GDB will have their sources
284 Z8000 simulator z8k-zilog-none or z8ksim
285 Matsushita MN10200 w/simulator mn10200-*-*
286 H8/500 simulator h8500-hitachi-hms or h8500hms
287 HP/PA running BSD hppa*-*-bsd*
288 HP/PA running OSF/1 hppa*-*-osf*
289 HP/PA Pro target hppa*-*-pro*
290 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
291 Sequent family i[3456]86-sequent-sysv4*
292 i[3456]86-sequent-sysv*
293 i[3456]86-sequent-bsd*
294 Tsqware Sparclet sparclet-*-*
295 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
297 * REMOVED configurations and files
300 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
301 IBM AIX PS/2 i[3456]86-*-aix
302 i386 running Mach 3.0 i[3456]86-*-mach3*
303 i386 running Mach i[3456]86-*-mach*
304 i386 running OSF/1 i[3456]86-*osf1mk*
305 HP/Apollo 68k Family m68*-apollo*-sysv*,
307 m68*-hp-bsd*, m68*-hp-hpux*
308 Argonaut Risc Chip (ARC) arc-*-*
309 Mitsubishi D30V d30v-*-*
310 Fujitsu FR30 fr30-*-elf*
311 OS/9000 i[34]86-*-os9k
312 I960 with MON960 i960-*-coff
314 * MIPS $fp behavior changed
316 The convenience variable $fp, for the MIPS, now consistently returns
317 the address of the current frame's base. Previously, depending on the
318 context, $fp could refer to either $sp or the current frame's base
319 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
320 The GNU Source-Level Debugger''.
322 *** Changes in GDB 5.3:
324 * GNU/Linux shared library multi-threaded performance improved.
326 When debugging a multi-threaded application on GNU/Linux, GDB now uses
327 `/proc', in preference to `ptrace' for memory reads. This may result
328 in an improvement in the start-up time of multi-threaded, shared
329 library applications when run under GDB. One GDB user writes: ``loads
330 shared libs like mad''.
332 * ``gdbserver'' now supports multi-threaded applications on some targets
334 Support for debugging multi-threaded applications which use
335 the GNU/Linux LinuxThreads package has been added for
336 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
337 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
339 * GDB now supports C/C++ preprocessor macros.
341 GDB now expands preprocessor macro invocations in C/C++ expressions,
342 and provides various commands for showing macro definitions and how
345 The new command `macro expand EXPRESSION' expands any macro
346 invocations in expression, and shows the result.
348 The new command `show macro MACRO-NAME' shows the definition of the
349 macro named MACRO-NAME, and where it was defined.
351 Most compilers don't include information about macros in the debugging
352 information by default. In GCC 3.1, for example, you need to compile
353 your program with the options `-gdwarf-2 -g3'. If the macro
354 information is present in the executable, GDB will read it.
356 * Multi-arched targets.
358 DEC Alpha (partial) alpha*-*-*
359 DEC VAX (partial) vax-*-*
361 National Semiconductor NS32000 (partial) ns32k-*-*
362 Motorola 68000 (partial) m68k-*-*
363 Motorola MCORE mcore-*-*
367 Fujitsu FRV architecture added by Red Hat frv*-*-*
370 * New native configurations
372 Alpha NetBSD alpha*-*-netbsd*
373 SH NetBSD sh*-*-netbsdelf*
374 MIPS NetBSD mips*-*-netbsd*
375 UltraSPARC NetBSD sparc64-*-netbsd*
377 * OBSOLETE configurations and files
379 Configurations that have been declared obsolete in this release have
380 been commented out. Unless there is activity to revive these
381 configurations, the next release of GDB will have their sources
384 Mitsubishi D30V d30v-*-*
385 OS/9000 i[34]86-*-os9k
386 IBM AIX PS/2 i[3456]86-*-aix
387 Fujitsu FR30 fr30-*-elf*
388 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
389 Argonaut Risc Chip (ARC) arc-*-*
390 i386 running Mach 3.0 i[3456]86-*-mach3*
391 i386 running Mach i[3456]86-*-mach*
392 i386 running OSF/1 i[3456]86-*osf1mk*
393 HP/Apollo 68k Family m68*-apollo*-sysv*,
395 m68*-hp-bsd*, m68*-hp-hpux*
396 I960 with MON960 i960-*-coff
400 CHILL, a Pascal like language used by telecommunications companies.
402 * REMOVED configurations and files
404 AMD 29k family via UDI a29k-amd-udi, udi29k
405 A29K VxWorks a29k-*-vxworks
406 AMD 29000 embedded, using EBMON a29k-none-none
407 AMD 29000 embedded with COFF a29k-none-coff
408 AMD 29000 embedded with a.out a29k-none-aout
410 testsuite/gdb.hp/gdb.threads-hp/ directory
412 * New command "set max-user-call-depth <nnn>"
414 This command allows the user to limit the call depth of user-defined
415 commands. The default is 1024.
417 * Changes in FreeBSD/i386 native debugging.
419 Support for the "generate-core-file" has been added.
421 * New commands "dump", "append", and "restore".
423 These commands allow data to be copied from target memory
424 to a bfd-format or binary file (dump and append), and back
425 from a file into memory (restore).
427 * Improved "next/step" support on multi-processor Alpha Tru64.
429 The previous single-step mechanism could cause unpredictable problems,
430 including the random appearance of SIGSEGV or SIGTRAP signals. The use
431 of a software single-step mechanism prevents this.
433 *** Changes in GDB 5.2.1:
441 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
442 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
443 Fix, by Joel Brobecker imported from mainline.
445 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
446 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
447 Fix, by Fred Fish, imported from mainline.
449 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
450 Surprisingly enough, it works now.
451 By Michal Ludvig, imported from mainline.
453 i386 hardware watchpoint support:
454 avoid misses on second run for some targets.
455 By Pierre Muller, imported from mainline.
457 *** Changes in GDB 5.2:
459 * New command "set trust-readonly-sections on[off]".
461 This command is a hint that tells gdb that read-only sections
462 really are read-only (ie. that their contents will not change).
463 In this mode, gdb will go to the object file rather than the
464 target to read memory from read-only sections (such as ".text").
465 This can be a significant performance improvement on some
466 (notably embedded) targets.
468 * New command "generate-core-file" (or "gcore").
470 This new gdb command allows the user to drop a core file of the child
471 process state at any time. So far it's been implemented only for
472 GNU/Linux and Solaris, but should be relatively easily ported to other
473 hosts. Argument is core file name (defaults to core.<pid>).
475 * New command line option
477 GDB now accepts --pid or -p followed by a process id.
479 * Change in command line behavior -- corefiles vs. process ids.
481 There is a subtle behavior in the way in which GDB handles
482 command line arguments. The first non-flag argument is always
483 a program to debug, but the second non-flag argument may either
484 be a corefile or a process id. Previously, GDB would attempt to
485 open the second argument as a corefile, and if that failed, would
486 issue a superfluous error message and then attempt to attach it as
487 a process. Now, if the second argument begins with a non-digit,
488 it will be treated as a corefile. If it begins with a digit,
489 GDB will attempt to attach it as a process, and if no such process
490 is found, will then attempt to open it as a corefile.
492 * Changes in ARM configurations.
494 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
495 configuration is fully multi-arch.
497 * New native configurations
499 ARM NetBSD arm*-*-netbsd*
500 x86 OpenBSD i[3456]86-*-openbsd*
501 AMD x86-64 running GNU/Linux x86_64-*-linux-*
502 Sparc64 running FreeBSD sparc64-*-freebsd*
506 Sanyo XStormy16 xstormy16-elf
508 * OBSOLETE configurations and files
510 Configurations that have been declared obsolete in this release have
511 been commented out. Unless there is activity to revive these
512 configurations, the next release of GDB will have their sources
515 AMD 29k family via UDI a29k-amd-udi, udi29k
516 A29K VxWorks a29k-*-vxworks
517 AMD 29000 embedded, using EBMON a29k-none-none
518 AMD 29000 embedded with COFF a29k-none-coff
519 AMD 29000 embedded with a.out a29k-none-aout
521 testsuite/gdb.hp/gdb.threads-hp/ directory
523 * REMOVED configurations and files
525 TI TMS320C80 tic80-*-*
527 PowerPC Solaris powerpcle-*-solaris*
528 PowerPC Windows NT powerpcle-*-cygwin32
529 PowerPC Netware powerpc-*-netware*
530 Harris/CXUX m88k m88*-harris-cxux*
531 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
532 ns32k-utek-sysv* ns32k-utek-*
533 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
534 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
535 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
536 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
537 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
539 * Changes to command line processing
541 The new `--args' feature can be used to specify command-line arguments
542 for the inferior from gdb's command line.
544 * Changes to key bindings
546 There is a new `operate-and-get-next' function bound to `C-o'.
548 *** Changes in GDB 5.1.1
550 Fix compile problem on DJGPP.
552 Fix a problem with floating-point registers on the i386 being
555 Fix to stop GDB crashing on .debug_str debug info.
557 Numerous documentation fixes.
559 Numerous testsuite fixes.
561 *** Changes in GDB 5.1:
563 * New native configurations
565 Alpha FreeBSD alpha*-*-freebsd*
566 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
567 MIPS GNU/Linux mips*-*-linux*
568 MIPS SGI Irix 6.x mips*-sgi-irix6*
570 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
574 Motorola 68HC11 and 68HC12 m68hc11-elf
576 UltraSparc running GNU/Linux sparc64-*-linux*
578 * OBSOLETE configurations and files
580 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
581 Harris/CXUX m88k m88*-harris-cxux*
582 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
583 ns32k-utek-sysv* ns32k-utek-*
584 TI TMS320C80 tic80-*-*
586 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
587 PowerPC Solaris powerpcle-*-solaris*
588 PowerPC Windows NT powerpcle-*-cygwin32
589 PowerPC Netware powerpc-*-netware*
590 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
591 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
592 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
593 Apple Macintosh (MPW) host N/A
595 stuff.c (Program to stuff files into a specially prepared space in kdb)
596 kdb-start.c (Main loop for the standalone kernel debugger)
598 Configurations that have been declared obsolete in this release have
599 been commented out. Unless there is activity to revive these
600 configurations, the next release of GDB will have their sources
603 * REMOVED configurations and files
605 Altos 3068 m68*-altos-*
606 Convex c1-*-*, c2-*-*
608 ARM RISCix arm-*-* (as host)
612 * GDB has been converted to ISO C.
614 GDB's source code has been converted to ISO C. In particular, the
615 sources are fully protoized, and rely on standard headers being
620 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
622 * The MI enabled by default.
624 The new machine oriented interface (MI) introduced in GDB 5.0 has been
625 revised and enabled by default. Packages which use GDB as a debugging
626 engine behind a UI or another front end are encouraged to switch to
627 using the GDB/MI interface, instead of the old annotations interface
628 which is now deprecated.
630 * Support for debugging Pascal programs.
632 GDB now includes support for debugging Pascal programs. The following
633 main features are supported:
635 - Pascal-specific data types such as sets;
637 - automatic recognition of Pascal sources based on file-name
640 - Pascal-style display of data types, variables, and functions;
642 - a Pascal expression parser.
644 However, some important features are not yet supported.
646 - Pascal string operations are not supported at all;
648 - there are some problems with boolean types;
650 - Pascal type hexadecimal constants are not supported
651 because they conflict with the internal variables format;
653 - support for Pascal objects and classes is not full yet;
655 - unlike Pascal, GDB is case-sensitive for symbol names.
657 * Changes in completion.
659 Commands such as `shell', `run' and `set args', which pass arguments
660 to inferior programs, now complete on file names, similar to what
661 users expect at the shell prompt.
663 Commands which accept locations, such as `disassemble', `print',
664 `breakpoint', `until', etc. now complete on filenames as well as
665 program symbols. Thus, if you type "break foob TAB", and the source
666 files linked into the programs include `foobar.c', that file name will
667 be one of the candidates for completion. However, file names are not
668 considered for completion after you typed a colon that delimits a file
669 name from a name of a function in that file, as in "break foo.c:bar".
671 `set demangle-style' completes on available demangling styles.
673 * New platform-independent commands:
675 It is now possible to define a post-hook for a command as well as a
676 hook that runs before the command. For more details, see the
677 documentation of `hookpost' in the GDB manual.
679 * Changes in GNU/Linux native debugging.
681 Support for debugging multi-threaded programs has been completely
682 revised for all platforms except m68k and sparc. You can now debug as
683 many threads as your system allows you to have.
685 Attach/detach is supported for multi-threaded programs.
687 Support for SSE registers was added for x86. This doesn't work for
688 multi-threaded programs though.
690 * Changes in MIPS configurations.
692 Multi-arch support is enabled for all MIPS configurations.
694 GDB can now be built as native debugger on SGI Irix 6.x systems for
695 debugging n32 executables. (Debugging 64-bit executables is not yet
698 * Unified support for hardware watchpoints in all x86 configurations.
700 Most (if not all) native x86 configurations support hardware-assisted
701 breakpoints and watchpoints in a unified manner. This support
702 implements debug register sharing between watchpoints, which allows to
703 put a virtually infinite number of watchpoints on the same address,
704 and also supports watching regions up to 16 bytes with several debug
707 The new maintenance command `maintenance show-debug-regs' toggles
708 debugging print-outs in functions that insert, remove, and test
709 watchpoints and hardware breakpoints.
711 * Changes in the DJGPP native configuration.
713 New command ``info dos sysinfo'' displays assorted information about
714 the CPU, OS, memory, and DPMI server.
716 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
717 display information about segment descriptors stored in GDT, LDT, and
720 New commands ``info dos pde'' and ``info dos pte'' display entries
721 from Page Directory and Page Tables (for now works with CWSDPMI only).
722 New command ``info dos address-pte'' displays the Page Table entry for
723 a given linear address.
725 GDB can now pass command lines longer than 126 characters to the
726 program being debugged (requires an update to the libdbg.a library
727 which is part of the DJGPP development kit).
729 DWARF2 debug info is now supported.
731 It is now possible to `step' and `next' through calls to `longjmp'.
733 * Changes in documentation.
735 All GDB documentation was converted to GFDL, the GNU Free
736 Documentation License.
738 Tracepoints-related commands are now fully documented in the GDB
741 TUI, the Text-mode User Interface, is now documented in the manual.
743 Tracepoints-related commands are now fully documented in the GDB
746 The "GDB Internals" manual now has an index. It also includes
747 documentation of `ui_out' functions, GDB coding standards, x86
748 hardware watchpoints, and memory region attributes.
750 * GDB's version number moved to ``version.in''
752 The Makefile variable VERSION has been replaced by the file
753 ``version.in''. People creating GDB distributions should update the
754 contents of this file.
758 GUD support is now a standard part of the EMACS distribution.
760 *** Changes in GDB 5.0:
762 * Improved support for debugging FP programs on x86 targets
764 Unified and much-improved support for debugging floating-point
765 programs on all x86 targets. In particular, ``info float'' now
766 displays the FP registers in the same format on all x86 targets, with
767 greater level of detail.
769 * Improvements and bugfixes in hardware-assisted watchpoints
771 It is now possible to watch array elements, struct members, and
772 bitfields with hardware-assisted watchpoints. Data-read watchpoints
773 on x86 targets no longer erroneously trigger when the address is
776 * Improvements in the native DJGPP version of GDB
778 The distribution now includes all the scripts and auxiliary files
779 necessary to build the native DJGPP version on MS-DOS/MS-Windows
780 machines ``out of the box''.
782 The DJGPP version can now debug programs that use signals. It is
783 possible to catch signals that happened in the debuggee, deliver
784 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
785 would kill the program being debugged.) Programs that hook hardware
786 interrupts (keyboard, timer, etc.) can also be debugged.
788 It is now possible to debug DJGPP programs that redirect their
789 standard handles or switch them to raw (as opposed to cooked) mode, or
790 even close them. The command ``run < foo > bar'' works as expected,
791 and ``info terminal'' reports useful information about the debuggee's
792 terminal, including raw/cooked mode, redirection, etc.
794 The DJGPP version now uses termios functions for console I/O, which
795 enables debugging graphics programs. Interrupting GDB with Ctrl-C
798 DOS-style file names with drive letters are now fully supported by
801 It is now possible to debug DJGPP programs that switch their working
802 directory. It is also possible to rerun the debuggee any number of
803 times without restarting GDB; thus, you can use the same setup,
804 breakpoints, etc. for many debugging sessions.
806 * New native configurations
808 ARM GNU/Linux arm*-*-linux*
809 PowerPC GNU/Linux powerpc-*-linux*
813 Motorola MCore mcore-*-*
814 x86 VxWorks i[3456]86-*-vxworks*
815 PowerPC VxWorks powerpc-*-vxworks*
816 TI TMS320C80 tic80-*-*
818 * OBSOLETE configurations
820 Altos 3068 m68*-altos-*
821 Convex c1-*-*, c2-*-*
823 ARM RISCix arm-*-* (as host)
826 Configurations that have been declared obsolete will be commented out,
827 but the code will be left in place. If there is no activity to revive
828 these configurations before the next release of GDB, the sources will
829 be permanently REMOVED.
831 * Gould support removed
833 Support for the Gould PowerNode and NP1 has been removed.
835 * New features for SVR4
837 On SVR4 native platforms (such as Solaris), if you attach to a process
838 without first loading a symbol file, GDB will now attempt to locate and
839 load symbols from the running process's executable file.
841 * Many C++ enhancements
843 C++ support has been greatly improved. Overload resolution now works properly
844 in almost all cases. RTTI support is on the way.
846 * Remote targets can connect to a sub-program
848 A popen(3) style serial-device has been added. This device starts a
849 sub-process (such as a stand-alone simulator) and then communicates
850 with that. The sub-program to run is specified using the syntax
851 ``|<program> <args>'' vis:
853 (gdb) set remotedebug 1
854 (gdb) target extended-remote |mn10300-elf-sim program-args
856 * MIPS 64 remote protocol
858 A long standing bug in the mips64 remote protocol where by GDB
859 expected certain 32 bit registers (ex SR) to be transfered as 32
860 instead of 64 bits has been fixed.
862 The command ``set remote-mips64-transfers-32bit-regs on'' has been
863 added to provide backward compatibility with older versions of GDB.
865 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
867 The command ``set remotebinarydownload'' command has been replaced by
868 ``set remote X-packet''. Other commands in ``set remote'' family
869 include ``set remote P-packet''.
871 * Breakpoint commands accept ranges.
873 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
874 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
875 ``tracepoint passcount'' also accepts a range of tracepoints.
877 * ``apropos'' command added.
879 The ``apropos'' command searches through command names and
880 documentation strings, printing out matches, making it much easier to
881 try to find a command that does what you are looking for.
885 A new machine oriented interface (MI) has been added to GDB. This
886 interface is designed for debug environments running GDB as a separate
887 process. This is part of the long term libGDB project. See the
888 "GDB/MI" chapter of the GDB manual for further information. It can be
889 enabled by configuring with:
891 .../configure --enable-gdbmi
893 *** Changes in GDB-4.18:
895 * New native configurations
897 HP-UX 10.20 hppa*-*-hpux10.20
898 HP-UX 11.x hppa*-*-hpux11.0*
899 M68K GNU/Linux m68*-*-linux*
903 Fujitsu FR30 fr30-*-elf*
904 Intel StrongARM strongarm-*-*
905 Mitsubishi D30V d30v-*-*
907 * OBSOLETE configurations
909 Gould PowerNode, NP1 np1-*-*, pn-*-*
911 Configurations that have been declared obsolete will be commented out,
912 but the code will be left in place. If there is no activity to revive
913 these configurations before the next release of GDB, the sources will
914 be permanently REMOVED.
918 As a compatibility experiment, GDB's source files buildsym.h and
919 buildsym.c have been converted to pure standard C, no longer
920 containing any K&R compatibility code. We believe that all systems in
921 use today either come with a standard C compiler, or have a GCC port
922 available. If this is not true, please report the affected
923 configuration to bug-gdb@gnu.org immediately. See the README file for
924 information about getting a standard C compiler if you don't have one
929 GDB now uses readline 2.2.
931 * set extension-language
933 You can now control the mapping between filename extensions and source
934 languages by using the `set extension-language' command. For instance,
935 you can ask GDB to treat .c files as C++ by saying
936 set extension-language .c c++
937 The command `info extensions' lists all of the recognized extensions
938 and their associated languages.
940 * Setting processor type for PowerPC and RS/6000
942 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
943 you can use the `set processor' command to specify what variant of the
944 PowerPC family you are debugging. The command
948 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
949 following PowerPC and RS6000 variants:
951 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
952 rs6000 IBM RS6000 ("POWER") architecture, user-level view
954 403GC IBM PowerPC 403GC
955 505 Motorola PowerPC 505
956 860 Motorola PowerPC 860 or 850
957 601 Motorola PowerPC 601
958 602 Motorola PowerPC 602
959 603 Motorola/IBM PowerPC 603 or 603e
960 604 Motorola PowerPC 604 or 604e
961 750 Motorola/IBM PowerPC 750 or 750
963 At the moment, this command just tells GDB what to name the
964 special-purpose processor registers. Since almost all the affected
965 registers are inaccessible to user-level programs, this command is
966 only useful for remote debugging in its present form.
970 Thanks to a major code donation from Hewlett-Packard, GDB now has much
971 more extensive support for HP-UX. Added features include shared
972 library support, kernel threads and hardware watchpoints for 11.00,
973 support for HP's ANSI C and C++ compilers, and a compatibility mode
974 for xdb and dbx commands.
978 HP's donation includes the new concept of catchpoints, which is a
979 generalization of the old catch command. On HP-UX, it is now possible
980 to catch exec, fork, and vfork, as well as library loading.
982 This means that the existing catch command has changed; its first
983 argument now specifies the type of catch to be set up. See the
984 output of "help catch" for a list of catchpoint types.
986 * Debugging across forks
988 On HP-UX, you can choose which process to debug when a fork() happens
993 HP has donated a curses-based terminal user interface (TUI). To get
994 it, build with --enable-tui. Although this can be enabled for any
995 configuration, at present it only works for native HP debugging.
997 * GDB remote protocol additions
999 A new protocol packet 'X' that writes binary data is now available.
1000 Default behavior is to try 'X', then drop back to 'M' if the stub
1001 fails to respond. The settable variable `remotebinarydownload'
1002 allows explicit control over the use of 'X'.
1004 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
1005 full 64-bit address. The command
1007 set remoteaddresssize 32
1009 can be used to revert to the old behaviour. For existing remote stubs
1010 the change should not be noticed, as the additional address information
1013 In order to assist in debugging stubs, you may use the maintenance
1014 command `packet' to send any text string to the stub. For instance,
1016 maint packet heythere
1018 sends the packet "$heythere#<checksum>". Note that it is very easy to
1019 disrupt a debugging session by sending the wrong packet at the wrong
1022 The compare-sections command allows you to compare section data on the
1023 target to what is in the executable file without uploading or
1024 downloading, by comparing CRC checksums.
1026 * Tracing can collect general expressions
1028 You may now collect general expressions at tracepoints. This requires
1029 further additions to the target-side stub; see tracepoint.c and
1030 doc/agentexpr.texi for further details.
1032 * mask-address variable for Mips
1034 For Mips targets, you may control the zeroing of the upper 32 bits of
1035 a 64-bit address by entering `set mask-address on'. This is mainly
1036 of interest to users of embedded R4xxx and R5xxx processors.
1038 * Higher serial baud rates
1040 GDB's serial code now allows you to specify baud rates 57600, 115200,
1041 230400, and 460800 baud. (Note that your host system may not be able
1042 to achieve all of these rates.)
1046 The i960 configuration now includes an initial implementation of a
1047 builtin simulator, contributed by Jim Wilson.
1050 *** Changes in GDB-4.17:
1052 * New native configurations
1054 Alpha GNU/Linux alpha*-*-linux*
1055 Unixware 2.x i[3456]86-unixware2*
1056 Irix 6.x mips*-sgi-irix6*
1057 PowerPC GNU/Linux powerpc-*-linux*
1058 PowerPC Solaris powerpcle-*-solaris*
1059 Sparc GNU/Linux sparc-*-linux*
1060 Motorola sysV68 R3V7.1 m68k-motorola-sysv
1064 Argonaut Risc Chip (ARC) arc-*-*
1065 Hitachi H8/300S h8300*-*-*
1066 Matsushita MN10200 w/simulator mn10200-*-*
1067 Matsushita MN10300 w/simulator mn10300-*-*
1068 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1069 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1070 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1071 Mitsubishi D10V w/simulator d10v-*-*
1072 Mitsubishi M32R/D w/simulator m32r-*-elf*
1073 Tsqware Sparclet sparclet-*-*
1074 NEC V850 w/simulator v850-*-*
1076 * New debugging protocols
1078 ARM with RDI protocol arm*-*-*
1079 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1080 DDB and LSI variants of PMON protocol mips*-*-*
1081 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1082 PowerPC with SDS protocol powerpc{,le}-*-eabi
1083 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1087 All configurations can now understand and use the DWARF 2 debugging
1088 format. The choice is automatic, if the symbol file contains DWARF 2
1093 GDB now includes basic Java language support. This support is
1094 only useful with Java compilers that produce native machine code.
1096 * solib-absolute-prefix and solib-search-path
1098 For SunOS and SVR4 shared libraries, you may now set the prefix for
1099 loading absolute shared library symbol files, and the search path for
1100 locating non-absolute shared library symbol files.
1102 * Live range splitting
1104 GDB can now effectively debug code for which GCC has performed live
1105 range splitting as part of its optimization. See gdb/doc/LRS for
1106 more details on the expected format of the stabs information.
1110 GDB's support for the GNU Hurd, including thread debugging, has been
1111 updated to work with current versions of the Hurd.
1115 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1116 instruction set. ARM GDB automatically detects when Thumb
1117 instructions are in use, and adjusts disassembly and backtracing
1122 GDB's MIPS target configurations now handle the MIP16 16-bit
1127 GDB now includes support for overlays; if an executable has been
1128 linked such that multiple sections are based at the same address, GDB
1129 will decide which section to use for symbolic info. You can choose to
1130 control the decision manually, using overlay commands, or implement
1131 additional target-side support and use "overlay load-target" to bring
1132 in the overlay mapping. Do "help overlay" for more detail.
1136 The command "info symbol <address>" displays information about
1137 the symbol at the specified address.
1141 The standard remote protocol now includes an extension that allows
1142 asynchronous collection and display of trace data. This requires
1143 extensive support in the target-side debugging stub. Tracing mode
1144 includes a new interaction mode in GDB and new commands: see the
1145 file tracepoint.c for more details.
1149 Configurations for embedded MIPS now include a simulator contributed
1150 by Cygnus Solutions. The simulator supports the instruction sets
1151 of most MIPS variants.
1155 Sparc configurations may now include the ERC32 simulator contributed
1156 by the European Space Agency. The simulator is not built into
1157 Sparc targets by default; configure with --enable-sim to include it.
1161 For target configurations that may include multiple variants of a
1162 basic architecture (such as MIPS and SH), you may now set the
1163 architecture explicitly. "set arch" sets, "info arch" lists
1164 the possible architectures.
1166 *** Changes in GDB-4.16:
1168 * New native configurations
1170 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1171 M68K NetBSD m68k-*-netbsd*
1172 PowerPC AIX 4.x powerpc-*-aix*
1173 PowerPC MacOS powerpc-*-macos*
1174 PowerPC Windows NT powerpcle-*-cygwin32
1175 RS/6000 AIX 4.x rs6000-*-aix4*
1179 ARM with RDP protocol arm-*-*
1180 I960 with MON960 i960-*-coff
1181 MIPS VxWorks mips*-*-vxworks*
1182 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1183 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1185 Matra Sparclet sparclet-*-*
1189 The powerpc-eabi configuration now includes the PSIM simulator,
1190 contributed by Andrew Cagney, with assistance from Mike Meissner.
1191 PSIM is a very elaborate model of the PowerPC, including not only
1192 basic instruction set execution, but also details of execution unit
1193 performance and I/O hardware. See sim/ppc/README for more details.
1197 GDB now works with Solaris 2.5.
1199 * Windows 95/NT native
1201 GDB will now work as a native debugger on Windows 95 and Windows NT.
1202 To build it from source, you must use the "gnu-win32" environment,
1203 which uses a DLL to emulate enough of Unix to run the GNU tools.
1204 Further information, binaries, and sources are available at
1205 ftp.cygnus.com, under pub/gnu-win32.
1207 * dont-repeat command
1209 If a user-defined command includes the command `dont-repeat', then the
1210 command will not be repeated if the user just types return. This is
1211 useful if the command is time-consuming to run, so that accidental
1212 extra keystrokes don't run the same command many times.
1214 * Send break instead of ^C
1216 The standard remote protocol now includes an option to send a break
1217 rather than a ^C to the target in order to interrupt it. By default,
1218 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1220 * Remote protocol timeout
1222 The standard remote protocol includes a new variable `remotetimeout'
1223 that allows you to set the number of seconds before GDB gives up trying
1224 to read from the target. The default value is 2.
1226 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1228 By default GDB will automatically keep track of objects as they are
1229 loaded and unloaded by the dynamic linker. By using the command `set
1230 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1231 when shared library events occur, thus allowing you to set breakpoints
1232 in shared libraries which are explicitly loaded by the inferior.
1234 Note this feature does not work on hpux8. On hpux9 you must link
1235 /usr/lib/end.o into your program. This feature should work
1236 automatically on hpux10.
1238 * Irix 5.x hardware watchpoint support
1240 Irix 5 configurations now support the use of hardware watchpoints.
1242 * Mips protocol "SYN garbage limit"
1244 When debugging a Mips target using the `target mips' protocol, you
1245 may set the number of characters that GDB will ignore by setting
1246 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1247 every character. The default value is 1050.
1249 * Recording and replaying remote debug sessions
1251 If you set `remotelogfile' to the name of a file, gdb will write to it
1252 a recording of a remote debug session. This recording may then be
1253 replayed back to gdb using "gdbreplay". See gdbserver/README for
1254 details. This is useful when you have a problem with GDB while doing
1255 remote debugging; you can make a recording of the session and send it
1256 to someone else, who can then recreate the problem.
1258 * Speedups for remote debugging
1260 GDB includes speedups for downloading and stepping MIPS systems using
1261 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1262 and more efficient S-record downloading.
1264 * Memory use reductions and statistics collection
1266 GDB now uses less memory and reports statistics about memory usage.
1267 Try the `maint print statistics' command, for example.
1269 *** Changes in GDB-4.15:
1271 * Psymtabs for XCOFF
1273 The symbol reader for AIX GDB now uses partial symbol tables. This
1274 can greatly improve startup time, especially for large executables.
1276 * Remote targets use caching
1278 Remote targets now use a data cache to speed up communication with the
1279 remote side. The data cache could lead to incorrect results because
1280 it doesn't know about volatile variables, thus making it impossible to
1281 debug targets which use memory mapped I/O devices. `set remotecache
1282 off' turns the the data cache off.
1284 * Remote targets may have threads
1286 The standard remote protocol now includes support for multiple threads
1287 in the target system, using new protocol commands 'H' and 'T'. See
1288 gdb/remote.c for details.
1292 If GDB is configured with `--enable-netrom', then it will include
1293 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1294 acts as though it is a bank of ROM on the target board, but you can
1295 write into it over the network. GDB's support consists only of
1296 support for fast loading into the emulated ROM; to debug, you must use
1297 another protocol, such as standard remote protocol. The usual
1298 sequence is something like
1300 target nrom <netrom-hostname>
1302 target remote <netrom-hostname>:1235
1306 GDB now includes support for the Apple Macintosh, as a host only. It
1307 may be run as either an MPW tool or as a standalone application, and
1308 it can debug through the serial port. All the usual GDB commands are
1309 available, but to the target command, you must supply "serial" as the
1310 device type instead of "/dev/ttyXX". See mpw-README in the main
1311 directory for more information on how to build. The MPW configuration
1312 scripts */mpw-config.in support only a few targets, and only the
1313 mips-idt-ecoff target has been tested.
1317 GDB configuration now uses autoconf. This is not user-visible,
1318 but does simplify configuration and building.
1322 GDB now supports hpux10.
1324 *** Changes in GDB-4.14:
1326 * New native configurations
1328 x86 FreeBSD i[345]86-*-freebsd
1329 x86 NetBSD i[345]86-*-netbsd
1330 NS32k NetBSD ns32k-*-netbsd
1331 Sparc NetBSD sparc-*-netbsd
1335 A29K VxWorks a29k-*-vxworks
1336 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1337 CPU32 EST-300 emulator m68*-*-est*
1338 PowerPC ELF powerpc-*-elf
1341 * Alpha OSF/1 support for procfs
1343 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1344 possible to attach to running processes. As the mounting of the /proc
1345 filesystem is optional on the Alpha, GDB automatically determines
1346 the availability of /proc during startup. This can lead to problems
1347 if /proc is unmounted after GDB has been started.
1349 * Arguments to user-defined commands
1351 User commands may accept up to 10 arguments separated by whitespace.
1352 Arguments are accessed within the user command via $arg0..$arg9. A
1355 print $arg0 + $arg1 + $arg2
1357 To execute the command use:
1360 Defines the command "adder" which prints the sum of its three arguments.
1361 Note the arguments are text substitutions, so they may reference variables,
1362 use complex expressions, or even perform inferior function calls.
1364 * New `if' and `while' commands
1366 This makes it possible to write more sophisticated user-defined
1367 commands. Both commands take a single argument, which is the
1368 expression to evaluate, and must be followed by the commands to
1369 execute, one per line, if the expression is nonzero, the list being
1370 terminated by the word `end'. The `if' command list may include an
1371 `else' word, which causes the following commands to be executed only
1372 if the expression is zero.
1374 * Fortran source language mode
1376 GDB now includes partial support for Fortran 77. It will recognize
1377 Fortran programs and can evaluate a subset of Fortran expressions, but
1378 variables and functions may not be handled correctly. GDB will work
1379 with G77, but does not yet know much about symbols emitted by other
1382 * Better HPUX support
1384 Most debugging facilities now work on dynamic executables for HPPAs
1385 running hpux9 or later. You can attach to running dynamically linked
1386 processes, but by default the dynamic libraries will be read-only, so
1387 for instance you won't be able to put breakpoints in them. To change
1388 that behavior do the following before running the program:
1394 This will cause the libraries to be mapped private and read-write.
1395 To revert to the normal behavior, do this:
1401 You cannot set breakpoints or examine data in the library until after
1402 the library is loaded if the function/data symbols do not have
1405 GDB can now also read debug symbols produced by the HP C compiler on
1406 HPPAs (sorry, no C++, Fortran or 68k support).
1408 * Target byte order now dynamically selectable
1410 You can choose which byte order to use with a target system, via the
1411 commands "set endian big" and "set endian little", and you can see the
1412 current setting by using "show endian". You can also give the command
1413 "set endian auto", in which case GDB will use the byte order
1414 associated with the executable. Currently, only embedded MIPS
1415 configurations support dynamic selection of target byte order.
1417 * New DOS host serial code
1419 This version uses DPMI interrupts to handle buffered I/O, so you
1420 no longer need to run asynctsr when debugging boards connected to
1423 *** Changes in GDB-4.13:
1425 * New "complete" command
1427 This lists all the possible completions for the rest of the line, if it
1428 were to be given as a command itself. This is intended for use by emacs.
1430 * Trailing space optional in prompt
1432 "set prompt" no longer adds a space for you after the prompt you set. This
1433 allows you to set a prompt which ends in a space or one that does not.
1435 * Breakpoint hit counts
1437 "info break" now displays a count of the number of times the breakpoint
1438 has been hit. This is especially useful in conjunction with "ignore"; you
1439 can ignore a large number of breakpoint hits, look at the breakpoint info
1440 to see how many times the breakpoint was hit, then run again, ignoring one
1441 less than that number, and this will get you quickly to the last hit of
1444 * Ability to stop printing at NULL character
1446 "set print null-stop" will cause GDB to stop printing the characters of
1447 an array when the first NULL is encountered. This is useful when large
1448 arrays actually contain only short strings.
1450 * Shared library breakpoints
1452 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1453 breakpoints in shared libraries before the executable is run.
1455 * Hardware watchpoints
1457 There is a new hardware breakpoint for the watch command for sparclite
1458 targets. See gdb/sparclite/hw_breakpoint.note.
1460 Hardware watchpoints are also now supported under GNU/Linux.
1464 Annotations have been added. These are for use with graphical interfaces,
1465 and are still experimental. Currently only gdba.el uses these.
1467 * Improved Irix 5 support
1469 GDB now works properly with Irix 5.2.
1471 * Improved HPPA support
1473 GDB now works properly with the latest GCC and GAS.
1475 * New native configurations
1477 Sequent PTX4 i[34]86-sequent-ptx4
1478 HPPA running OSF/1 hppa*-*-osf*
1479 Atari TT running SVR4 m68*-*-sysv4*
1480 RS/6000 LynxOS rs6000-*-lynxos*
1484 OS/9000 i[34]86-*-os9k
1485 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1488 * Hitachi SH7000 and E7000-PC ICE support
1490 There is now support for communicating with the Hitachi E7000-PC ICE.
1491 This is available automatically when GDB is configured for the SH.
1495 As usual, a variety of small fixes and improvements, both generic
1496 and configuration-specific. See the ChangeLog for more detail.
1498 *** Changes in GDB-4.12:
1500 * Irix 5 is now supported
1504 GDB-4.12 on the HPPA has a number of changes which make it unable
1505 to debug the output from the currently released versions of GCC and
1506 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1507 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1508 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1511 *** Changes in GDB-4.11:
1513 * User visible changes:
1517 The "set remotedebug" option is now consistent between the mips remote
1518 target, remote targets using the gdb-specific protocol, UDI (AMD's
1519 debug protocol for the 29k) and the 88k bug monitor. It is now an
1520 integer specifying a debug level (normally 0 or 1, but 2 means more
1521 debugging info for the mips target).
1523 * DEC Alpha native support
1525 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1526 debug info, but GDB works fairly well with the DEC compiler and should
1527 work with a future GCC release. See the README file for a few
1528 Alpha-specific notes.
1530 * Preliminary thread implementation
1532 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1534 * LynxOS native and target support for 386
1536 This release has been hosted on LynxOS 2.2, and also can be configured
1537 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1540 * Improvements in C++ mangling/demangling.
1542 This release has much better g++ debugging, specifically in name
1543 mangling/demangling, virtual function calls, print virtual table,
1544 call methods, ...etc.
1546 *** Changes in GDB-4.10:
1548 * User visible changes:
1550 Remote debugging using the GDB-specific (`target remote') protocol now
1551 supports the `load' command. This is only useful if you have some
1552 other way of getting the stub to the target system, and you can put it
1553 somewhere in memory where it won't get clobbered by the download.
1555 Filename completion now works.
1557 When run under emacs mode, the "info line" command now causes the
1558 arrow to point to the line specified. Also, "info line" prints
1559 addresses in symbolic form (as well as hex).
1561 All vxworks based targets now support a user settable option, called
1562 vxworks-timeout. This option represents the number of seconds gdb
1563 should wait for responses to rpc's. You might want to use this if
1564 your vxworks target is, perhaps, a slow software simulator or happens
1565 to be on the far side of a thin network line.
1569 This release contains support for using a DEC alpha as a GDB host for
1570 cross debugging. Native alpha debugging is not supported yet.
1573 *** Changes in GDB-4.9:
1577 This is the first GDB release which is accompanied by a matching testsuite.
1578 The testsuite requires installation of dejagnu, which should be available
1579 via ftp from most sites that carry GNU software.
1583 'Cfront' style demangling has had its name changed to 'ARM' style, to
1584 emphasize that it was written from the specifications in the C++ Annotated
1585 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1586 disclaimers, it still generated too much confusion with users attempting to
1587 use gdb with AT&T cfront.
1591 GDB now uses a standard remote interface to a simulator library.
1592 So far, the library contains simulators for the Zilog Z8001/2, the
1593 Hitachi H8/300, H8/500 and Super-H.
1595 * New targets supported
1597 H8/300 simulator h8300-hitachi-hms or h8300hms
1598 H8/500 simulator h8500-hitachi-hms or h8500hms
1599 SH simulator sh-hitachi-hms or sh
1600 Z8000 simulator z8k-zilog-none or z8ksim
1601 IDT MIPS board over serial line mips-idt-ecoff
1603 Cross-debugging to GO32 targets is supported. It requires a custom
1604 version of the i386-stub.c module which is integrated with the
1605 GO32 memory extender.
1607 * New remote protocols
1609 MIPS remote debugging protocol.
1611 * New source languages supported
1613 This version includes preliminary support for Chill, a Pascal like language
1614 used by telecommunications companies. Chill support is also being integrated
1615 into the GNU compiler, but we don't know when it will be publically available.
1618 *** Changes in GDB-4.8:
1620 * HP Precision Architecture supported
1622 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1623 version of this support was available as a set of patches from the
1624 University of Utah. GDB does not support debugging of programs
1625 compiled with the HP compiler, because HP will not document their file
1626 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1627 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1629 Many problems in the preliminary version have been fixed.
1631 * Faster and better demangling
1633 We have improved template demangling and fixed numerous bugs in the GNU style
1634 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1635 character types (wchar_t) are now supported. Demangling of each symbol is now
1636 only done once, and is cached when the symbol table for a file is read in.
1637 This results in a small increase in memory usage for C programs, a moderate
1638 increase in memory usage for C++ programs, and a fantastic speedup in
1641 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1642 from the specifications in the Annotated Reference Manual, which AT&T's
1643 compiler does not actually implement.
1645 * G++ multiple inheritance compiler problem
1647 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1648 inheritance lattices was reworked to properly discover ambiguities. We
1649 recently found an example which causes this new algorithm to fail in a
1650 very subtle way, producing bad debug information for those classes.
1651 The file 'gcc.patch' (in this directory) can be applied to gcc to
1652 circumvent the problem. A future GCC release will contain a complete
1655 The previous G++ debug info problem (mentioned below for the gdb-4.7
1656 release) is fixed in gcc version 2.3.2.
1658 * Improved configure script
1660 The `configure' script will now attempt to guess your system type if
1661 you don't supply a host system type. The old scheme of supplying a
1662 host system triplet is preferable over using this. All the magic is
1663 done in the new `config.guess' script. Examine it for details.
1665 We have also brought our configure script much more in line with the FSF's
1666 version. It now supports the --with-xxx options. In particular,
1667 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1668 The resulting GDB will not be able to read arbitrary object file formats --
1669 only the format ``expected'' to be used on the configured target system.
1670 We hope to make this the default in a future release.
1672 * Documentation improvements
1674 There's new internal documentation on how to modify GDB, and how to
1675 produce clean changes to the code. We implore people to read it
1676 before submitting changes.
1678 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1679 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1680 `info' files are also provided. To build `info' files from scratch,
1681 you will need the latest `makeinfo' release, which will be available in
1682 a future texinfo-X.Y release.
1684 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1685 We're not sure exactly which versions have this problem, but it has
1686 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1687 or better. If that isn't possible, there is a patch in
1688 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1689 around this problem.
1693 GDB now supports array constants that can be used in expressions typed in by
1694 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1695 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1698 The new directory `gdb/sparclite' contains a program that demonstrates
1699 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1701 * New native hosts supported
1703 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1704 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1706 * New targets supported
1708 AMD 29k family via UDI a29k-amd-udi or udi29k
1710 * New file formats supported
1712 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1713 HPUX core files, and SCO 3.2v2 core files.
1717 Attaching to processes now works again; thanks for the many bug reports.
1719 We have also stomped on a bunch of core dumps caused by
1720 printf_filtered("%s") problems.
1722 We eliminated a copyright problem on the rpc and ptrace header files
1723 for VxWorks, which was discovered at the last minute during the 4.7
1724 release. You should now be able to build a VxWorks GDB.
1726 You can now interrupt gdb while an attached process is running. This
1727 will cause the attached process to stop, and give control back to GDB.
1729 We fixed problems caused by using too many file descriptors
1730 for reading symbols from object files and libraries. This was
1731 especially a problem for programs that used many (~100) shared
1734 The `step' command now only enters a subroutine if there is line number
1735 information for the subroutine. Otherwise it acts like the `next'
1736 command. Previously, `step' would enter subroutines if there was
1737 any debugging information about the routine. This avoids problems
1738 when using `cc -g1' on MIPS machines.
1740 * Internal improvements
1742 GDB's internal interfaces have been improved to make it easier to support
1743 debugging of multiple languages in the future.
1745 GDB now uses a common structure for symbol information internally.
1746 Minimal symbols (derived from linkage symbols in object files), partial
1747 symbols (from a quick scan of debug information), and full symbols
1748 contain a common subset of information, making it easier to write
1749 shared code that handles any of them.
1751 * New command line options
1753 We now accept --silent as an alias for --quiet.
1757 The memory-mapped-malloc library is now licensed under the GNU Library
1758 General Public License.
1760 *** Changes in GDB-4.7:
1762 * Host/native/target split
1764 GDB has had some major internal surgery to untangle the support for
1765 hosts and remote targets. Now, when you configure GDB for a remote
1766 target, it will no longer load in all of the support for debugging
1767 local programs on the host. When fully completed and tested, this will
1768 ensure that arbitrary host/target combinations are possible.
1770 The primary conceptual shift is to separate the non-portable code in
1771 GDB into three categories. Host specific code is required any time GDB
1772 is compiled on that host, regardless of the target. Target specific
1773 code relates to the peculiarities of the target, but can be compiled on
1774 any host. Native specific code is everything else: it can only be
1775 built when the host and target are the same system. Child process
1776 handling and core file support are two common `native' examples.
1778 GDB's use of /proc for controlling Unix child processes is now cleaner.
1779 It has been split out into a single module under the `target_ops' vector,
1780 plus two native-dependent functions for each system that uses /proc.
1782 * New hosts supported
1784 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1785 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1786 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1788 * New targets supported
1790 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1791 68030 and CPU32 m68030-*-*, m68332-*-*
1793 * New native hosts supported
1795 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1796 (386bsd is not well tested yet)
1797 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1799 * New file formats supported
1801 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1802 supports reading of `a.out.adobe' object files, which are an a.out
1803 format extended with minimal information about multiple sections.
1807 `show copying' is the same as the old `info copying'.
1808 `show warranty' is the same as `info warrantee'.
1809 These were renamed for consistency. The old commands continue to work.
1811 `info handle' is a new alias for `info signals'.
1813 You can now define pre-command hooks, which attach arbitrary command
1814 scripts to any command. The commands in the hook will be executed
1815 prior to the user's command. You can also create a hook which will be
1816 executed whenever the program stops. See gdb.texinfo.
1820 We now deal with Cfront style name mangling, and can even extract type
1821 info from mangled symbols. GDB can automatically figure out which
1822 symbol mangling style your C++ compiler uses.
1824 Calling of methods and virtual functions has been improved as well.
1828 The crash that occured when debugging Sun Ansi-C compiled binaries is
1829 fixed. This was due to mishandling of the extra N_SO stabs output
1832 We also finally got Ultrix 4.2 running in house, and fixed core file
1833 support, with help from a dozen people on the net.
1835 John M. Farrell discovered that the reason that single-stepping was so
1836 slow on all of the Mips based platforms (primarily SGI and DEC) was
1837 that we were trying to demangle and lookup a symbol used for internal
1838 purposes on every instruction that was being stepped through. Changing
1839 the name of that symbol so that it couldn't be mistaken for a C++
1840 mangled symbol sped things up a great deal.
1842 Rich Pixley sped up symbol lookups in general by getting much smarter
1843 about when C++ symbol mangling is necessary. This should make symbol
1844 completion (TAB on the command line) much faster. It's not as fast as
1845 we'd like, but it's significantly faster than gdb-4.6.
1849 A new user controllable variable 'call_scratch_address' can
1850 specify the location of a scratch area to be used when GDB
1851 calls a function in the target. This is necessary because the
1852 usual method of putting the scratch area on the stack does not work
1853 in systems that have separate instruction and data spaces.
1855 We integrated changes to support the 29k UDI (Universal Debugger
1856 Interface), but discovered at the last minute that we didn't have all
1857 of the appropriate copyright paperwork. We are working with AMD to
1858 resolve this, and hope to have it available soon.
1862 We have sped up the remote serial line protocol, especially for targets
1863 with lots of registers. It now supports a new `expedited status' ('T')
1864 message which can be used in place of the existing 'S' status message.
1865 This allows the remote stub to send only the registers that GDB
1866 needs to make a quick decision about single-stepping or conditional
1867 breakpoints, eliminating the need to fetch the entire register set for
1868 each instruction being stepped through.
1870 The GDB remote serial protocol now implements a write-through cache for
1871 registers, only re-reading the registers if the target has run.
1873 There is also a new remote serial stub for SPARC processors. You can
1874 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1875 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1876 processor with a serial port.
1880 Configure.in files have become much easier to read and modify. A new
1881 `table driven' format makes it more obvious what configurations are
1882 supported, and what files each one uses.
1886 There is a new opcodes library which will eventually contain all of the
1887 disassembly routines and opcode tables. At present, it only contains
1888 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1889 disassembler (binutils/objdump) to share these routines.
1891 The libiberty library is now copylefted under the GNU Library General
1892 Public License. This allows more liberal use, and was done so libg++
1893 can use it. This makes no difference to GDB, since the Library License
1894 grants all the rights from the General Public License.
1898 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1899 reference to the stabs symbol info used by the debugger. It is (as far
1900 as we know) the only published document on this fascinating topic. We
1901 encourage you to read it, compare it to the stabs information on your
1902 system, and send improvements on the document in general (to
1903 bug-gdb@prep.ai.mit.edu).
1905 And, of course, many bugs have been fixed.
1908 *** Changes in GDB-4.6:
1910 * Better support for C++ function names
1912 GDB now accepts as input the "demangled form" of C++ overloaded function
1913 names and member function names, and can do command completion on such names
1914 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1915 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1916 Make use of command completion, it is your friend.
1918 GDB also now accepts a variety of C++ mangled symbol formats. They are
1919 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1920 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1921 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1922 for the list of formats.
1924 * G++ symbol mangling problem
1926 Recent versions of gcc have a bug in how they emit debugging information for
1927 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1928 directory) can be applied to gcc to fix the problem. Alternatively, if you
1929 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1930 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1931 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1934 * New 'maintenance' command
1936 All of the commands related to hacking GDB internals have been moved out of
1937 the main command set, and now live behind the 'maintenance' command. This
1938 can also be abbreviated as 'mt'. The following changes were made:
1940 dump-me -> maintenance dump-me
1941 info all-breakpoints -> maintenance info breakpoints
1942 printmsyms -> maintenance print msyms
1943 printobjfiles -> maintenance print objfiles
1944 printpsyms -> maintenance print psymbols
1945 printsyms -> maintenance print symbols
1947 The following commands are new:
1949 maintenance demangle Call internal GDB demangler routine to
1950 demangle a C++ link name and prints the result.
1951 maintenance print type Print a type chain for a given symbol
1953 * Change to .gdbinit file processing
1955 We now read the $HOME/.gdbinit file before processing the argv arguments
1956 (e.g. reading symbol files or core files). This allows global parameters to
1957 be set, which will apply during the symbol reading. The ./.gdbinit is still
1958 read after argv processing.
1960 * New hosts supported
1962 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1964 GNU/Linux support i386-unknown-linux or linux
1966 We are also including code to support the HP/PA running BSD and HPUX. This
1967 is almost guaranteed not to work, as we didn't have time to test or build it
1968 for this release. We are including it so that the more adventurous (or
1969 masochistic) of you can play with it. We also had major problems with the
1970 fact that the compiler that we got from HP doesn't support the -g option.
1973 * New targets supported
1975 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1977 * More smarts about finding #include files
1979 GDB now remembers the compilation directory for all include files, and for
1980 all files from which C is generated (like yacc and lex sources). This
1981 greatly improves GDB's ability to find yacc/lex sources, and include files,
1982 especially if you are debugging your program from a directory different from
1983 the one that contains your sources.
1985 We also fixed a bug which caused difficulty with listing and setting
1986 breakpoints in include files which contain C code. (In the past, you had to
1987 try twice in order to list an include file that you hadn't looked at before.)
1989 * Interesting infernals change
1991 GDB now deals with arbitrary numbers of sections, where the symbols for each
1992 section must be relocated relative to that section's landing place in the
1993 target's address space. This work was needed to support ELF with embedded
1994 stabs used by Solaris-2.0.
1996 * Bug fixes (of course!)
1998 There have been loads of fixes for the following things:
1999 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
2000 i960, stabs, DOS(GO32), procfs, etc...
2002 See the ChangeLog for details.
2004 *** Changes in GDB-4.5:
2006 * New machines supported (host and target)
2008 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
2010 SGI Irix-4.x mips-sgi-irix4 or iris4
2012 * New malloc package
2014 GDB now uses a new memory manager called mmalloc, based on gmalloc.
2015 Mmalloc is capable of handling mutiple heaps of memory. It is also
2016 capable of saving a heap to a file, and then mapping it back in later.
2017 This can be used to greatly speedup the startup of GDB by using a
2018 pre-parsed symbol table which lives in a mmalloc managed heap. For
2019 more details, please read mmalloc/mmalloc.texi.
2023 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
2024 'help info proc' for details.
2026 * MIPS ecoff symbol table format
2028 The code that reads MIPS symbol table format is now supported on all hosts.
2029 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
2032 * File name changes for MS-DOS
2034 Many files in the config directories have been renamed to make it easier to
2035 support GDB on MS-DOSe systems (which have very restrictive file name
2036 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
2037 environment) is close to working but has some remaining problems. Note
2038 that debugging of DOS programs is not supported, due to limitations
2039 in the ``operating system'', but it can be used to host cross-debugging.
2041 * Cross byte order fixes
2043 Many fixes have been made to support cross debugging of Sparc and MIPS
2044 targets from hosts whose byte order differs.
2046 * New -mapped and -readnow options
2048 If memory-mapped files are available on your system through the 'mmap'
2049 system call, you can use the -mapped option on the `file' or
2050 `symbol-file' commands to cause GDB to write the symbols from your
2051 program into a reusable file. If the program you are debugging is
2052 called `/path/fred', the mapped symbol file will be `./fred.syms'.
2053 Future GDB debugging sessions will notice the presence of this file,
2054 and will quickly map in symbol information from it, rather than reading
2055 the symbol table from the executable program. Using the '-mapped'
2056 option in a GDB `file' or `symbol-file' command has the same effect as
2057 starting GDB with the '-mapped' command-line option.
2059 You can cause GDB to read the entire symbol table immediately by using
2060 the '-readnow' option with any of the commands that load symbol table
2061 information (or on the GDB command line). This makes the command
2062 slower, but makes future operations faster.
2064 The -mapped and -readnow options are typically combined in order to
2065 build a `fred.syms' file that contains complete symbol information.
2066 A simple GDB invocation to do nothing but build a `.syms' file for future
2069 gdb -batch -nx -mapped -readnow programname
2071 The `.syms' file is specific to the host machine on which GDB is run.
2072 It holds an exact image of GDB's internal symbol table. It cannot be
2073 shared across multiple host platforms.
2075 * longjmp() handling
2077 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2078 siglongjmp() without losing control. This feature has not yet been ported to
2079 all systems. It currently works on many 386 platforms, all MIPS-based
2080 platforms (SGI, DECstation, etc), and Sun3/4.
2084 Preliminary work has been put in to support the new Solaris OS from Sun. At
2085 this time, it can control and debug processes, but it is not capable of
2090 As always, many many bug fixes. The major areas were with g++, and mipsread.
2091 People using the MIPS-based platforms should experience fewer mysterious
2092 crashes and trashed symbol tables.
2094 *** Changes in GDB-4.4:
2096 * New machines supported (host and target)
2098 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2100 BSD Reno on Vax vax-dec-bsd
2101 Ultrix on Vax vax-dec-ultrix
2103 * New machines supported (target)
2105 AMD 29000 embedded, using EBMON a29k-none-none
2109 GDB continues to improve its handling of C++. `References' work better.
2110 The demangler has also been improved, and now deals with symbols mangled as
2111 per the Annotated C++ Reference Guide.
2113 GDB also now handles `stabs' symbol information embedded in MIPS
2114 `ecoff' symbol tables. Since the ecoff format was not easily
2115 extensible to handle new languages such as C++, this appeared to be a
2116 good way to put C++ debugging info into MIPS binaries. This option
2117 will be supported in the GNU C compiler, version 2, when it is
2120 * New features for SVR4
2122 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2123 shared libraries. Debugging dynamically linked programs should present
2124 only minor differences from debugging statically linked programs.
2126 The `info proc' command will print out information about any process
2127 on an SVR4 system (including the one you are debugging). At the moment,
2128 it prints the address mappings of the process.
2130 If you bring up GDB on another SVR4 system, please send mail to
2131 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2133 * Better dynamic linking support in SunOS
2135 Reading symbols from shared libraries which contain debugging symbols
2136 now works properly. However, there remain issues such as automatic
2137 skipping of `transfer vector' code during function calls, which
2138 make it harder to debug code in a shared library, than to debug the
2139 same code linked statically.
2143 GDB is now using the latest `getopt' routines from the FSF. This
2144 version accepts the -- prefix for options with long names. GDB will
2145 continue to accept the old forms (-option and +option) as well.
2146 Various single letter abbreviations for options have been explicity
2147 added to the option table so that they won't get overshadowed in the
2148 future by other options that begin with the same letter.
2152 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2153 Many assorted bugs have been handled. Many more remain to be handled.
2154 See the various ChangeLog files (primarily in gdb and bfd) for details.
2157 *** Changes in GDB-4.3:
2159 * New machines supported (host and target)
2161 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2162 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2163 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2165 * Almost SCO Unix support
2167 We had hoped to support:
2168 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2169 (except for core file support), but we discovered very late in the release
2170 that it has problems with process groups that render gdb unusable. Sorry
2171 about that. I encourage people to fix it and post the fixes.
2173 * Preliminary ELF and DWARF support
2175 GDB can read ELF object files on System V Release 4, and can handle
2176 debugging records for C, in DWARF format, in ELF files. This support
2177 is preliminary. If you bring up GDB on another SVR4 system, please
2178 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2183 GDB now uses the latest `readline' library. One user-visible change
2184 is that two tabs will list possible command completions, which previously
2185 required typing M-? (meta-question mark, or ESC ?).
2189 The `stepi' bug that many of you noticed has been squashed.
2190 Many bugs in C++ have been handled. Many more remain to be handled.
2191 See the various ChangeLog files (primarily in gdb and bfd) for details.
2193 * State of the MIPS world (in case you wondered):
2195 GDB can understand the symbol tables emitted by the compilers
2196 supplied by most vendors of MIPS-based machines, including DEC. These
2197 symbol tables are in a format that essentially nobody else uses.
2199 Some versions of gcc come with an assembler post-processor called
2200 mips-tfile. This program is required if you want to do source-level
2201 debugging of gcc-compiled programs. I believe FSF does not ship
2202 mips-tfile with gcc version 1, but it will eventually come with gcc
2205 Debugging of g++ output remains a problem. g++ version 1.xx does not
2206 really support it at all. (If you're lucky, you should be able to get
2207 line numbers and stack traces to work, but no parameters or local
2208 variables.) With some work it should be possible to improve the
2211 When gcc version 2 is released, you will have somewhat better luck.
2212 However, even then you will get confusing results for inheritance and
2215 We will eventually provide full debugging of g++ output on
2216 DECstations. This will probably involve some kind of stabs-in-ecoff
2217 encapulation, but the details have not been worked out yet.
2220 *** Changes in GDB-4.2:
2222 * Improved configuration
2224 Only one copy of `configure' exists now, and it is not self-modifying.
2225 Porting BFD is simpler.
2229 The `step' and `next' commands now only stop at the first instruction
2230 of a source line. This prevents the multiple stops that used to occur
2231 in switch statements, for-loops, etc. `Step' continues to stop if a
2232 function that has debugging information is called within the line.
2236 Lots of small bugs fixed. More remain.
2238 * New host supported (not target)
2240 Intel 386 PC clone running Mach i386-none-mach
2243 *** Changes in GDB-4.1:
2245 * Multiple source language support
2247 GDB now has internal scaffolding to handle several source languages.
2248 It determines the type of each source file from its filename extension,
2249 and will switch expression parsing and number formatting to match the
2250 language of the function in the currently selected stack frame.
2251 You can also specifically set the language to be used, with
2252 `set language c' or `set language modula-2'.
2256 GDB now has preliminary support for the GNU Modula-2 compiler,
2257 currently under development at the State University of New York at
2258 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2259 continue through the fall of 1991 and into 1992.
2261 Other Modula-2 compilers are currently not supported, and attempting to
2262 debug programs compiled with them will likely result in an error as the
2263 symbol table is read. Feel free to work on it, though!
2265 There are hooks in GDB for strict type checking and range checking,
2266 in the `Modula-2 philosophy', but they do not currently work.
2270 GDB can now write to executable and core files (e.g. patch
2271 a variable's value). You must turn this switch on, specify
2272 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2273 by assigning a new value to a variable. Modifications take
2276 * Automatic SunOS shared library reading
2278 When you run your program, GDB automatically determines where its
2279 shared libraries (if any) have been loaded, and reads their symbols.
2280 The `share' command is no longer needed. This also works when
2281 examining core files.
2285 You can specify the number of lines that the `list' command shows.
2288 * New machines supported (host and target)
2290 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2291 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2292 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2294 * New hosts supported (not targets)
2296 IBM RT/PC: romp-ibm-aix or rtpc
2298 * New targets supported (not hosts)
2300 AMD 29000 embedded with COFF a29k-none-coff
2301 AMD 29000 embedded with a.out a29k-none-aout
2302 Ultracomputer remote kernel debug a29k-nyu-kern
2304 * New remote interfaces
2310 *** Changes in GDB-4.0:
2314 Wide output is wrapped at good places to make the output more readable.
2316 Gdb now supports cross-debugging from a host machine of one type to a
2317 target machine of another type. Communication with the target system
2318 is over serial lines. The ``target'' command handles connecting to the
2319 remote system; the ``load'' command will download a program into the
2320 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2321 also supports debugging of realtime processes running under VxWorks,
2322 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2323 stub on the target system.
2325 New CPUs supported include the AMD 29000 and Intel 960.
2327 GDB now reads object files and symbol tables via a ``binary file''
2328 library, which allows a single copy of GDB to debug programs of multiple
2329 object file types such as a.out and coff.
2331 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2332 refcard.dvi and refcard.ps are available to format it).
2335 * Control-Variable user interface simplified
2337 All variables that control the operation of the debugger can be set
2338 by the ``set'' command, and displayed by the ``show'' command.
2340 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2341 ``Show prompt'' produces the response:
2342 Gdb's prompt is new-gdb=>.
2344 What follows are the NEW set commands. The command ``help set'' will
2345 print a complete list of old and new set commands. ``help set FOO''
2346 will give a longer description of the variable FOO. ``show'' will show
2347 all of the variable descriptions and their current settings.
2349 confirm on/off: Enables warning questions for operations that are
2350 hard to recover from, e.g. rerunning the program while
2351 it is already running. Default is ON.
2353 editing on/off: Enables EMACS style command line editing
2354 of input. Previous lines can be recalled with
2355 control-P, the current line can be edited with control-B,
2356 you can search for commands with control-R, etc.
2359 history filename NAME: NAME is where the gdb command history
2360 will be stored. The default is .gdb_history,
2361 or the value of the environment variable
2364 history size N: The size, in commands, of the command history. The
2365 default is 256, or the value of the environment variable
2368 history save on/off: If this value is set to ON, the history file will
2369 be saved after exiting gdb. If set to OFF, the
2370 file will not be saved. The default is OFF.
2372 history expansion on/off: If this value is set to ON, then csh-like
2373 history expansion will be performed on
2374 command line input. The default is OFF.
2376 radix N: Sets the default radix for input and output. It can be set
2377 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2378 in the current radix, so "set radix 10" is always a no-op.
2380 height N: This integer value is the number of lines on a page. Default
2381 is 24, the current `stty rows'' setting, or the ``li#''
2382 setting from the termcap entry matching the environment
2385 width N: This integer value is the number of characters on a line.
2386 Default is 80, the current `stty cols'' setting, or the ``co#''
2387 setting from the termcap entry matching the environment
2390 Note: ``set screensize'' is obsolete. Use ``set height'' and
2391 ``set width'' instead.
2393 print address on/off: Print memory addresses in various command displays,
2394 such as stack traces and structure values. Gdb looks
2395 more ``symbolic'' if you turn this off; it looks more
2396 ``machine level'' with it on. Default is ON.
2398 print array on/off: Prettyprint arrays. New convenient format! Default
2401 print demangle on/off: Print C++ symbols in "source" form if on,
2404 print asm-demangle on/off: Same, for assembler level printouts
2407 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2410 * Support for Epoch Environment.
2412 The epoch environment is a version of Emacs v18 with windowing. One
2413 new command, ``inspect'', is identical to ``print'', except that if you
2414 are running in the epoch environment, the value is printed in its own
2418 * Support for Shared Libraries
2420 GDB can now debug programs and core files that use SunOS shared libraries.
2421 Symbols from a shared library cannot be referenced
2422 before the shared library has been linked with the program (this
2423 happens after you type ``run'' and before the function main() is entered).
2424 At any time after this linking (including when examining core files
2425 from dynamically linked programs), gdb reads the symbols from each
2426 shared library when you type the ``sharedlibrary'' command.
2427 It can be abbreviated ``share''.
2429 sharedlibrary REGEXP: Load shared object library symbols for files
2430 matching a unix regular expression. No argument
2431 indicates to load symbols for all shared libraries.
2433 info sharedlibrary: Status of loaded shared libraries.
2438 A watchpoint stops execution of a program whenever the value of an
2439 expression changes. Checking for this slows down execution
2440 tremendously whenever you are in the scope of the expression, but is
2441 quite useful for catching tough ``bit-spreader'' or pointer misuse
2442 problems. Some machines such as the 386 have hardware for doing this
2443 more quickly, and future versions of gdb will use this hardware.
2445 watch EXP: Set a watchpoint (breakpoint) for an expression.
2447 info watchpoints: Information about your watchpoints.
2449 delete N: Deletes watchpoint number N (same as breakpoints).
2450 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2451 enable N: Re-enables watchpoint number N (same as breakpoints).
2454 * C++ multiple inheritance
2456 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2459 * C++ exception handling
2461 Gdb now supports limited C++ exception handling. Besides the existing
2462 ability to breakpoint on an exception handler, gdb can breakpoint on
2463 the raising of an exception (before the stack is peeled back to the
2466 catch FOO: If there is a FOO exception handler in the dynamic scope,
2467 set a breakpoint to catch exceptions which may be raised there.
2468 Multiple exceptions (``catch foo bar baz'') may be caught.
2470 info catch: Lists all exceptions which may be caught in the
2471 current stack frame.
2474 * Minor command changes
2476 The command ``call func (arg, arg, ...)'' now acts like the print
2477 command, except it does not print or save a value if the function's result
2478 is void. This is similar to dbx usage.
2480 The ``up'' and ``down'' commands now always print the frame they end up
2481 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2482 frames without printing.
2484 * New directory command
2486 'dir' now adds directories to the FRONT of the source search path.
2487 The path starts off empty. Source files that contain debug information
2488 about the directory in which they were compiled can be found even
2489 with an empty path; Sun CC and GCC include this information. If GDB can't
2490 find your source file in the current directory, type "dir .".
2492 * Configuring GDB for compilation
2494 For normal use, type ``./configure host''. See README or gdb.texinfo
2497 GDB now handles cross debugging. If you are remotely debugging between
2498 two different machines, type ``./configure host -target=targ''.
2499 Host is the machine where GDB will run; targ is the machine
2500 where the program that you are debugging will run.