1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.0:
6 * Removed --with-mmalloc
8 Support for the mmalloc memory manager has been removed, as it
9 conflicted with the internal gdb byte cache.
11 * Changes in AMD64 configurations
13 The AMD64 target now includes the %cs and %ss registers. As a result
14 the AMD64 remote protocol has changed; this affects the floating-point
15 and SSE registers. If you rely on those registers for your debugging,
16 you should upgrade gdbserver on the remote side.
18 * Revised SPARC target
20 The SPARC target has been completely revised, incorporating the
21 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
22 support for LynxOS and SunOS 4 has been dropped. Calling functions
23 from within GDB on operating systems with a non-executable stack
24 (Solaris, OpenBSD) now works.
28 GDB has a new C++ demangler which does a better job on the mangled
29 names generated by current versions of g++. It also runs faster, so
30 with this and other changes gdb should now start faster on large C++
33 * DWARF 2 Location Expressions
35 GDB support for location expressions has been extended to support function
36 arguments and frame bases. Older versions of GDB could crash when they
39 * New native configurations
41 NetBSD/amd64 x86_64-*-netbsd*
42 OpenBSD/sparc sparc-*-openbsd*
43 OpenBSD/sparc64 sparc64-*-openbsd*
45 * New debugging protocols
47 M32R with SDI protocol m32r-*-elf*
49 * "set prompt-escape-char" command deleted.
51 The command "set prompt-escape-char" has been deleted. This command,
52 and its very obscure effet on GDB's prompt, was never documented,
53 tested, nor mentioned in the NEWS file.
55 * OBSOLETE configurations and files
57 Configurations that have been declared obsolete in this release have
58 been commented out. Unless there is activity to revive these
59 configurations, the next release of GDB will have their sources
62 Sun 3, running SunOS 3 m68*-*-sunos3*
63 Sun 3, running SunOS 4 m68*-*-sunos4*
64 Sun 2, running SunOS 3 m68000-*-sunos3*
65 Sun 2, running SunOS 4 m68000-*-sunos4*
66 Motorola 680x0 running LynxOS m68*-*-lynxos*
67 AT&T 3b1/Unix pc m68*-att-*
68 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
69 decstation mips-dec-* mips-little-*
70 riscos mips-*-riscos* mips-*-sysv*
72 sysv mips*-*-sysv4* (IRIX 5/6 not included)
74 * REMOVED configurations and files
76 SGI Irix-4.x mips-sgi-irix4 or iris4
77 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
78 Z8000 simulator z8k-zilog-none or z8ksim
79 Matsushita MN10200 w/simulator mn10200-*-*
80 H8/500 simulator h8500-hitachi-hms or h8500hms
81 HP/PA running BSD hppa*-*-bsd*
82 HP/PA running OSF/1 hppa*-*-osf*
83 HP/PA Pro target hppa*-*-pro*
84 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
85 Sequent family i[3456]86-sequent-sysv4*
86 i[3456]86-sequent-sysv*
87 i[3456]86-sequent-bsd*
88 SPARC running LynxOS sparc-*-lynxos*
89 SPARC running SunOS 4 sparc-*-sunos4*
90 Tsqware Sparclet sparclet-*-*
91 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
93 *** Changes in GDB 6.0:
97 Support for debugging the Objective-C programming language has been
100 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
102 DWARF 2's Call Frame Information makes available compiler generated
103 information that more exactly describes the program's run-time stack.
104 By using this information, GDB is able to provide more robust stack
107 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
108 have been updated to use a new backtrace mechanism which includes
113 GDB's remote protocol has been extended to include support for hosted
114 file I/O (where the remote target uses GDB's file system). See GDB's
115 remote protocol documentation for details.
117 * All targets using the new architecture framework.
119 All of GDB's targets have been updated to use the new internal
120 architecture framework. The way is now open for future GDB releases
121 to include cross-architecture native debugging support (i386 on amd64,
124 * GNU/Linux's Thread Local Storage (TLS)
126 GDB now includes support for for the GNU/Linux implementation of
127 per-thread variables.
129 * GNU/Linux's Native POSIX Thread Library (NPTL)
131 GDB's thread code has been updated to work with either the new
132 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
134 * Separate debug info.
136 GDB, in conjunction with BINUTILS, now supports a mechanism for
137 automatically loading debug information from a separate file. Instead
138 of shipping full debug and non-debug versions of system libraries,
139 system integrators can now instead ship just the stripped libraries
140 and optional debug files.
142 * DWARF 2 Location Expressions
144 DWARF 2 Location Expressions allow the compiler to more completely
145 describe the location of variables (even in optimized code) to the
148 GDB now includes preliminary support for location expressions (support
149 for DW_OP_piece is still missing).
153 A number of long standing bugs that caused GDB to die while starting a
154 Java application have been fixed. GDB's Java support is now
155 considered "useable".
157 * GNU/Linux support for fork, vfork, and exec.
159 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
160 commands are now implemented for GNU/Linux. They require a 2.5.x or later
163 * GDB supports logging output to a file
165 There are two new commands, "set logging" and "show logging", which can be
166 used to capture GDB's output to a file.
168 * The meaning of "detach" has changed for gdbserver
170 The "detach" command will now resume the application, as documented. To
171 disconnect from gdbserver and leave it stopped, use the new "disconnect"
174 * d10v, m68hc11 `regs' command deprecated
176 The `info registers' command has been updated so that it displays the
177 registers using a format identical to the old `regs' command.
181 A new command, "maint set profile on/off", has been added. This command can
182 be used to enable or disable profiling while running GDB, to profile a
183 session or a set of commands. In addition there is a new configure switch,
184 "--enable-profiling", which will cause GDB to be compiled with profiling
185 data, for more informative profiling results.
187 * Default MI syntax changed to "mi2".
189 The default MI (machine interface) syntax, enabled by the command line
190 option "-i=mi", has been changed to "mi2". The previous MI syntax,
191 "mi1", can be enabled by specifying the option "-i=mi1".
193 Support for the original "mi0" syntax (included in GDB 5.0) has been
196 Fix for gdb/192: removed extraneous space when displaying frame level.
197 Fix for gdb/672: update changelist is now output in mi list format.
198 Fix for gdb/702: a -var-assign that updates the value now shows up
199 in a subsequent -var-update.
201 * New native configurations.
203 FreeBSD/amd64 x86_64-*-freebsd*
205 * Multi-arched targets.
207 HP/PA HPUX11 hppa*-*-hpux*
208 Renesas M32R/D w/simulator m32r-*-elf*
210 * OBSOLETE configurations and files
212 Configurations that have been declared obsolete in this release have
213 been commented out. Unless there is activity to revive these
214 configurations, the next release of GDB will have their sources
217 Z8000 simulator z8k-zilog-none or z8ksim
218 Matsushita MN10200 w/simulator mn10200-*-*
219 H8/500 simulator h8500-hitachi-hms or h8500hms
220 HP/PA running BSD hppa*-*-bsd*
221 HP/PA running OSF/1 hppa*-*-osf*
222 HP/PA Pro target hppa*-*-pro*
223 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
224 Sequent family i[3456]86-sequent-sysv4*
225 i[3456]86-sequent-sysv*
226 i[3456]86-sequent-bsd*
227 Tsqware Sparclet sparclet-*-*
228 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
230 * REMOVED configurations and files
233 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
234 IBM AIX PS/2 i[3456]86-*-aix
235 i386 running Mach 3.0 i[3456]86-*-mach3*
236 i386 running Mach i[3456]86-*-mach*
237 i386 running OSF/1 i[3456]86-*osf1mk*
238 HP/Apollo 68k Family m68*-apollo*-sysv*,
240 m68*-hp-bsd*, m68*-hp-hpux*
241 Argonaut Risc Chip (ARC) arc-*-*
242 Mitsubishi D30V d30v-*-*
243 Fujitsu FR30 fr30-*-elf*
244 OS/9000 i[34]86-*-os9k
245 I960 with MON960 i960-*-coff
247 * MIPS $fp behavior changed
249 The convenience variable $fp, for the MIPS, now consistently returns
250 the address of the current frame's base. Previously, depending on the
251 context, $fp could refer to either $sp or the current frame's base
252 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
253 The GNU Source-Level Debugger''.
255 *** Changes in GDB 5.3:
257 * GNU/Linux shared library multi-threaded performance improved.
259 When debugging a multi-threaded application on GNU/Linux, GDB now uses
260 `/proc', in preference to `ptrace' for memory reads. This may result
261 in an improvement in the start-up time of multi-threaded, shared
262 library applications when run under GDB. One GDB user writes: ``loads
263 shared libs like mad''.
265 * ``gdbserver'' now supports multi-threaded applications on some targets
267 Support for debugging multi-threaded applications which use
268 the GNU/Linux LinuxThreads package has been added for
269 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
270 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
272 * GDB now supports C/C++ preprocessor macros.
274 GDB now expands preprocessor macro invocations in C/C++ expressions,
275 and provides various commands for showing macro definitions and how
278 The new command `macro expand EXPRESSION' expands any macro
279 invocations in expression, and shows the result.
281 The new command `show macro MACRO-NAME' shows the definition of the
282 macro named MACRO-NAME, and where it was defined.
284 Most compilers don't include information about macros in the debugging
285 information by default. In GCC 3.1, for example, you need to compile
286 your program with the options `-gdwarf-2 -g3'. If the macro
287 information is present in the executable, GDB will read it.
289 * Multi-arched targets.
291 DEC Alpha (partial) alpha*-*-*
292 DEC VAX (partial) vax-*-*
294 National Semiconductor NS32000 (partial) ns32k-*-*
295 Motorola 68000 (partial) m68k-*-*
296 Motorola MCORE mcore-*-*
300 Fujitsu FRV architecture added by Red Hat frv*-*-*
303 * New native configurations
305 Alpha NetBSD alpha*-*-netbsd*
306 SH NetBSD sh*-*-netbsdelf*
307 MIPS NetBSD mips*-*-netbsd*
308 UltraSPARC NetBSD sparc64-*-netbsd*
310 * OBSOLETE configurations and files
312 Configurations that have been declared obsolete in this release have
313 been commented out. Unless there is activity to revive these
314 configurations, the next release of GDB will have their sources
317 Mitsubishi D30V d30v-*-*
318 OS/9000 i[34]86-*-os9k
319 IBM AIX PS/2 i[3456]86-*-aix
320 Fujitsu FR30 fr30-*-elf*
321 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
322 Argonaut Risc Chip (ARC) arc-*-*
323 i386 running Mach 3.0 i[3456]86-*-mach3*
324 i386 running Mach i[3456]86-*-mach*
325 i386 running OSF/1 i[3456]86-*osf1mk*
326 HP/Apollo 68k Family m68*-apollo*-sysv*,
328 m68*-hp-bsd*, m68*-hp-hpux*
329 I960 with MON960 i960-*-coff
333 CHILL, a Pascal like language used by telecommunications companies.
335 * REMOVED configurations and files
337 AMD 29k family via UDI a29k-amd-udi, udi29k
338 A29K VxWorks a29k-*-vxworks
339 AMD 29000 embedded, using EBMON a29k-none-none
340 AMD 29000 embedded with COFF a29k-none-coff
341 AMD 29000 embedded with a.out a29k-none-aout
343 testsuite/gdb.hp/gdb.threads-hp/ directory
345 * New command "set max-user-call-depth <nnn>"
347 This command allows the user to limit the call depth of user-defined
348 commands. The default is 1024.
350 * Changes in FreeBSD/i386 native debugging.
352 Support for the "generate-core-file" has been added.
354 * New commands "dump", "append", and "restore".
356 These commands allow data to be copied from target memory
357 to a bfd-format or binary file (dump and append), and back
358 from a file into memory (restore).
360 * Improved "next/step" support on multi-processor Alpha Tru64.
362 The previous single-step mechanism could cause unpredictable problems,
363 including the random appearance of SIGSEGV or SIGTRAP signals. The use
364 of a software single-step mechanism prevents this.
366 *** Changes in GDB 5.2.1:
374 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
375 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
376 Fix, by Joel Brobecker imported from mainline.
378 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
379 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
380 Fix, by Fred Fish, imported from mainline.
382 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
383 Surprisingly enough, it works now.
384 By Michal Ludvig, imported from mainline.
386 i386 hardware watchpoint support:
387 avoid misses on second run for some targets.
388 By Pierre Muller, imported from mainline.
390 *** Changes in GDB 5.2:
392 * New command "set trust-readonly-sections on[off]".
394 This command is a hint that tells gdb that read-only sections
395 really are read-only (ie. that their contents will not change).
396 In this mode, gdb will go to the object file rather than the
397 target to read memory from read-only sections (such as ".text").
398 This can be a significant performance improvement on some
399 (notably embedded) targets.
401 * New command "generate-core-file" (or "gcore").
403 This new gdb command allows the user to drop a core file of the child
404 process state at any time. So far it's been implemented only for
405 GNU/Linux and Solaris, but should be relatively easily ported to other
406 hosts. Argument is core file name (defaults to core.<pid>).
408 * New command line option
410 GDB now accepts --pid or -p followed by a process id.
412 * Change in command line behavior -- corefiles vs. process ids.
414 There is a subtle behavior in the way in which GDB handles
415 command line arguments. The first non-flag argument is always
416 a program to debug, but the second non-flag argument may either
417 be a corefile or a process id. Previously, GDB would attempt to
418 open the second argument as a corefile, and if that failed, would
419 issue a superfluous error message and then attempt to attach it as
420 a process. Now, if the second argument begins with a non-digit,
421 it will be treated as a corefile. If it begins with a digit,
422 GDB will attempt to attach it as a process, and if no such process
423 is found, will then attempt to open it as a corefile.
425 * Changes in ARM configurations.
427 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
428 configuration is fully multi-arch.
430 * New native configurations
432 ARM NetBSD arm*-*-netbsd*
433 x86 OpenBSD i[3456]86-*-openbsd*
434 AMD x86-64 running GNU/Linux x86_64-*-linux-*
435 Sparc64 running FreeBSD sparc64-*-freebsd*
439 Sanyo XStormy16 xstormy16-elf
441 * OBSOLETE configurations and files
443 Configurations that have been declared obsolete in this release have
444 been commented out. Unless there is activity to revive these
445 configurations, the next release of GDB will have their sources
448 AMD 29k family via UDI a29k-amd-udi, udi29k
449 A29K VxWorks a29k-*-vxworks
450 AMD 29000 embedded, using EBMON a29k-none-none
451 AMD 29000 embedded with COFF a29k-none-coff
452 AMD 29000 embedded with a.out a29k-none-aout
454 testsuite/gdb.hp/gdb.threads-hp/ directory
456 * REMOVED configurations and files
458 TI TMS320C80 tic80-*-*
460 PowerPC Solaris powerpcle-*-solaris*
461 PowerPC Windows NT powerpcle-*-cygwin32
462 PowerPC Netware powerpc-*-netware*
463 Harris/CXUX m88k m88*-harris-cxux*
464 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
465 ns32k-utek-sysv* ns32k-utek-*
466 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
467 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
468 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
469 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
470 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
472 * Changes to command line processing
474 The new `--args' feature can be used to specify command-line arguments
475 for the inferior from gdb's command line.
477 * Changes to key bindings
479 There is a new `operate-and-get-next' function bound to `C-o'.
481 *** Changes in GDB 5.1.1
483 Fix compile problem on DJGPP.
485 Fix a problem with floating-point registers on the i386 being
488 Fix to stop GDB crashing on .debug_str debug info.
490 Numerous documentation fixes.
492 Numerous testsuite fixes.
494 *** Changes in GDB 5.1:
496 * New native configurations
498 Alpha FreeBSD alpha*-*-freebsd*
499 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
500 MIPS GNU/Linux mips*-*-linux*
501 MIPS SGI Irix 6.x mips*-sgi-irix6*
503 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
507 Motorola 68HC11 and 68HC12 m68hc11-elf
509 UltraSparc running GNU/Linux sparc64-*-linux*
511 * OBSOLETE configurations and files
513 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
514 Harris/CXUX m88k m88*-harris-cxux*
515 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
516 ns32k-utek-sysv* ns32k-utek-*
517 TI TMS320C80 tic80-*-*
519 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
520 PowerPC Solaris powerpcle-*-solaris*
521 PowerPC Windows NT powerpcle-*-cygwin32
522 PowerPC Netware powerpc-*-netware*
523 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
524 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
525 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
526 Apple Macintosh (MPW) host N/A
528 stuff.c (Program to stuff files into a specially prepared space in kdb)
529 kdb-start.c (Main loop for the standalone kernel debugger)
531 Configurations that have been declared obsolete in this release have
532 been commented out. Unless there is activity to revive these
533 configurations, the next release of GDB will have their sources
536 * REMOVED configurations and files
538 Altos 3068 m68*-altos-*
539 Convex c1-*-*, c2-*-*
541 ARM RISCix arm-*-* (as host)
545 * GDB has been converted to ISO C.
547 GDB's source code has been converted to ISO C. In particular, the
548 sources are fully protoized, and rely on standard headers being
553 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
555 * The MI enabled by default.
557 The new machine oriented interface (MI) introduced in GDB 5.0 has been
558 revised and enabled by default. Packages which use GDB as a debugging
559 engine behind a UI or another front end are encouraged to switch to
560 using the GDB/MI interface, instead of the old annotations interface
561 which is now deprecated.
563 * Support for debugging Pascal programs.
565 GDB now includes support for debugging Pascal programs. The following
566 main features are supported:
568 - Pascal-specific data types such as sets;
570 - automatic recognition of Pascal sources based on file-name
573 - Pascal-style display of data types, variables, and functions;
575 - a Pascal expression parser.
577 However, some important features are not yet supported.
579 - Pascal string operations are not supported at all;
581 - there are some problems with boolean types;
583 - Pascal type hexadecimal constants are not supported
584 because they conflict with the internal variables format;
586 - support for Pascal objects and classes is not full yet;
588 - unlike Pascal, GDB is case-sensitive for symbol names.
590 * Changes in completion.
592 Commands such as `shell', `run' and `set args', which pass arguments
593 to inferior programs, now complete on file names, similar to what
594 users expect at the shell prompt.
596 Commands which accept locations, such as `disassemble', `print',
597 `breakpoint', `until', etc. now complete on filenames as well as
598 program symbols. Thus, if you type "break foob TAB", and the source
599 files linked into the programs include `foobar.c', that file name will
600 be one of the candidates for completion. However, file names are not
601 considered for completion after you typed a colon that delimits a file
602 name from a name of a function in that file, as in "break foo.c:bar".
604 `set demangle-style' completes on available demangling styles.
606 * New platform-independent commands:
608 It is now possible to define a post-hook for a command as well as a
609 hook that runs before the command. For more details, see the
610 documentation of `hookpost' in the GDB manual.
612 * Changes in GNU/Linux native debugging.
614 Support for debugging multi-threaded programs has been completely
615 revised for all platforms except m68k and sparc. You can now debug as
616 many threads as your system allows you to have.
618 Attach/detach is supported for multi-threaded programs.
620 Support for SSE registers was added for x86. This doesn't work for
621 multi-threaded programs though.
623 * Changes in MIPS configurations.
625 Multi-arch support is enabled for all MIPS configurations.
627 GDB can now be built as native debugger on SGI Irix 6.x systems for
628 debugging n32 executables. (Debugging 64-bit executables is not yet
631 * Unified support for hardware watchpoints in all x86 configurations.
633 Most (if not all) native x86 configurations support hardware-assisted
634 breakpoints and watchpoints in a unified manner. This support
635 implements debug register sharing between watchpoints, which allows to
636 put a virtually infinite number of watchpoints on the same address,
637 and also supports watching regions up to 16 bytes with several debug
640 The new maintenance command `maintenance show-debug-regs' toggles
641 debugging print-outs in functions that insert, remove, and test
642 watchpoints and hardware breakpoints.
644 * Changes in the DJGPP native configuration.
646 New command ``info dos sysinfo'' displays assorted information about
647 the CPU, OS, memory, and DPMI server.
649 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
650 display information about segment descriptors stored in GDT, LDT, and
653 New commands ``info dos pde'' and ``info dos pte'' display entries
654 from Page Directory and Page Tables (for now works with CWSDPMI only).
655 New command ``info dos address-pte'' displays the Page Table entry for
656 a given linear address.
658 GDB can now pass command lines longer than 126 characters to the
659 program being debugged (requires an update to the libdbg.a library
660 which is part of the DJGPP development kit).
662 DWARF2 debug info is now supported.
664 It is now possible to `step' and `next' through calls to `longjmp'.
666 * Changes in documentation.
668 All GDB documentation was converted to GFDL, the GNU Free
669 Documentation License.
671 Tracepoints-related commands are now fully documented in the GDB
674 TUI, the Text-mode User Interface, is now documented in the manual.
676 Tracepoints-related commands are now fully documented in the GDB
679 The "GDB Internals" manual now has an index. It also includes
680 documentation of `ui_out' functions, GDB coding standards, x86
681 hardware watchpoints, and memory region attributes.
683 * GDB's version number moved to ``version.in''
685 The Makefile variable VERSION has been replaced by the file
686 ``version.in''. People creating GDB distributions should update the
687 contents of this file.
691 GUD support is now a standard part of the EMACS distribution.
693 *** Changes in GDB 5.0:
695 * Improved support for debugging FP programs on x86 targets
697 Unified and much-improved support for debugging floating-point
698 programs on all x86 targets. In particular, ``info float'' now
699 displays the FP registers in the same format on all x86 targets, with
700 greater level of detail.
702 * Improvements and bugfixes in hardware-assisted watchpoints
704 It is now possible to watch array elements, struct members, and
705 bitfields with hardware-assisted watchpoints. Data-read watchpoints
706 on x86 targets no longer erroneously trigger when the address is
709 * Improvements in the native DJGPP version of GDB
711 The distribution now includes all the scripts and auxiliary files
712 necessary to build the native DJGPP version on MS-DOS/MS-Windows
713 machines ``out of the box''.
715 The DJGPP version can now debug programs that use signals. It is
716 possible to catch signals that happened in the debuggee, deliver
717 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
718 would kill the program being debugged.) Programs that hook hardware
719 interrupts (keyboard, timer, etc.) can also be debugged.
721 It is now possible to debug DJGPP programs that redirect their
722 standard handles or switch them to raw (as opposed to cooked) mode, or
723 even close them. The command ``run < foo > bar'' works as expected,
724 and ``info terminal'' reports useful information about the debuggee's
725 terminal, including raw/cooked mode, redirection, etc.
727 The DJGPP version now uses termios functions for console I/O, which
728 enables debugging graphics programs. Interrupting GDB with Ctrl-C
731 DOS-style file names with drive letters are now fully supported by
734 It is now possible to debug DJGPP programs that switch their working
735 directory. It is also possible to rerun the debuggee any number of
736 times without restarting GDB; thus, you can use the same setup,
737 breakpoints, etc. for many debugging sessions.
739 * New native configurations
741 ARM GNU/Linux arm*-*-linux*
742 PowerPC GNU/Linux powerpc-*-linux*
746 Motorola MCore mcore-*-*
747 x86 VxWorks i[3456]86-*-vxworks*
748 PowerPC VxWorks powerpc-*-vxworks*
749 TI TMS320C80 tic80-*-*
751 * OBSOLETE configurations
753 Altos 3068 m68*-altos-*
754 Convex c1-*-*, c2-*-*
756 ARM RISCix arm-*-* (as host)
759 Configurations that have been declared obsolete will be commented out,
760 but the code will be left in place. If there is no activity to revive
761 these configurations before the next release of GDB, the sources will
762 be permanently REMOVED.
764 * Gould support removed
766 Support for the Gould PowerNode and NP1 has been removed.
768 * New features for SVR4
770 On SVR4 native platforms (such as Solaris), if you attach to a process
771 without first loading a symbol file, GDB will now attempt to locate and
772 load symbols from the running process's executable file.
774 * Many C++ enhancements
776 C++ support has been greatly improved. Overload resolution now works properly
777 in almost all cases. RTTI support is on the way.
779 * Remote targets can connect to a sub-program
781 A popen(3) style serial-device has been added. This device starts a
782 sub-process (such as a stand-alone simulator) and then communicates
783 with that. The sub-program to run is specified using the syntax
784 ``|<program> <args>'' vis:
786 (gdb) set remotedebug 1
787 (gdb) target extended-remote |mn10300-elf-sim program-args
789 * MIPS 64 remote protocol
791 A long standing bug in the mips64 remote protocol where by GDB
792 expected certain 32 bit registers (ex SR) to be transfered as 32
793 instead of 64 bits has been fixed.
795 The command ``set remote-mips64-transfers-32bit-regs on'' has been
796 added to provide backward compatibility with older versions of GDB.
798 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
800 The command ``set remotebinarydownload'' command has been replaced by
801 ``set remote X-packet''. Other commands in ``set remote'' family
802 include ``set remote P-packet''.
804 * Breakpoint commands accept ranges.
806 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
807 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
808 ``tracepoint passcount'' also accepts a range of tracepoints.
810 * ``apropos'' command added.
812 The ``apropos'' command searches through command names and
813 documentation strings, printing out matches, making it much easier to
814 try to find a command that does what you are looking for.
818 A new machine oriented interface (MI) has been added to GDB. This
819 interface is designed for debug environments running GDB as a separate
820 process. This is part of the long term libGDB project. See the
821 "GDB/MI" chapter of the GDB manual for further information. It can be
822 enabled by configuring with:
824 .../configure --enable-gdbmi
826 *** Changes in GDB-4.18:
828 * New native configurations
830 HP-UX 10.20 hppa*-*-hpux10.20
831 HP-UX 11.x hppa*-*-hpux11.0*
832 M68K GNU/Linux m68*-*-linux*
836 Fujitsu FR30 fr30-*-elf*
837 Intel StrongARM strongarm-*-*
838 Mitsubishi D30V d30v-*-*
840 * OBSOLETE configurations
842 Gould PowerNode, NP1 np1-*-*, pn-*-*
844 Configurations that have been declared obsolete will be commented out,
845 but the code will be left in place. If there is no activity to revive
846 these configurations before the next release of GDB, the sources will
847 be permanently REMOVED.
851 As a compatibility experiment, GDB's source files buildsym.h and
852 buildsym.c have been converted to pure standard C, no longer
853 containing any K&R compatibility code. We believe that all systems in
854 use today either come with a standard C compiler, or have a GCC port
855 available. If this is not true, please report the affected
856 configuration to bug-gdb@gnu.org immediately. See the README file for
857 information about getting a standard C compiler if you don't have one
862 GDB now uses readline 2.2.
864 * set extension-language
866 You can now control the mapping between filename extensions and source
867 languages by using the `set extension-language' command. For instance,
868 you can ask GDB to treat .c files as C++ by saying
869 set extension-language .c c++
870 The command `info extensions' lists all of the recognized extensions
871 and their associated languages.
873 * Setting processor type for PowerPC and RS/6000
875 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
876 you can use the `set processor' command to specify what variant of the
877 PowerPC family you are debugging. The command
881 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
882 following PowerPC and RS6000 variants:
884 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
885 rs6000 IBM RS6000 ("POWER") architecture, user-level view
887 403GC IBM PowerPC 403GC
888 505 Motorola PowerPC 505
889 860 Motorola PowerPC 860 or 850
890 601 Motorola PowerPC 601
891 602 Motorola PowerPC 602
892 603 Motorola/IBM PowerPC 603 or 603e
893 604 Motorola PowerPC 604 or 604e
894 750 Motorola/IBM PowerPC 750 or 750
896 At the moment, this command just tells GDB what to name the
897 special-purpose processor registers. Since almost all the affected
898 registers are inaccessible to user-level programs, this command is
899 only useful for remote debugging in its present form.
903 Thanks to a major code donation from Hewlett-Packard, GDB now has much
904 more extensive support for HP-UX. Added features include shared
905 library support, kernel threads and hardware watchpoints for 11.00,
906 support for HP's ANSI C and C++ compilers, and a compatibility mode
907 for xdb and dbx commands.
911 HP's donation includes the new concept of catchpoints, which is a
912 generalization of the old catch command. On HP-UX, it is now possible
913 to catch exec, fork, and vfork, as well as library loading.
915 This means that the existing catch command has changed; its first
916 argument now specifies the type of catch to be set up. See the
917 output of "help catch" for a list of catchpoint types.
919 * Debugging across forks
921 On HP-UX, you can choose which process to debug when a fork() happens
926 HP has donated a curses-based terminal user interface (TUI). To get
927 it, build with --enable-tui. Although this can be enabled for any
928 configuration, at present it only works for native HP debugging.
930 * GDB remote protocol additions
932 A new protocol packet 'X' that writes binary data is now available.
933 Default behavior is to try 'X', then drop back to 'M' if the stub
934 fails to respond. The settable variable `remotebinarydownload'
935 allows explicit control over the use of 'X'.
937 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
938 full 64-bit address. The command
940 set remoteaddresssize 32
942 can be used to revert to the old behaviour. For existing remote stubs
943 the change should not be noticed, as the additional address information
946 In order to assist in debugging stubs, you may use the maintenance
947 command `packet' to send any text string to the stub. For instance,
949 maint packet heythere
951 sends the packet "$heythere#<checksum>". Note that it is very easy to
952 disrupt a debugging session by sending the wrong packet at the wrong
955 The compare-sections command allows you to compare section data on the
956 target to what is in the executable file without uploading or
957 downloading, by comparing CRC checksums.
959 * Tracing can collect general expressions
961 You may now collect general expressions at tracepoints. This requires
962 further additions to the target-side stub; see tracepoint.c and
963 doc/agentexpr.texi for further details.
965 * mask-address variable for Mips
967 For Mips targets, you may control the zeroing of the upper 32 bits of
968 a 64-bit address by entering `set mask-address on'. This is mainly
969 of interest to users of embedded R4xxx and R5xxx processors.
971 * Higher serial baud rates
973 GDB's serial code now allows you to specify baud rates 57600, 115200,
974 230400, and 460800 baud. (Note that your host system may not be able
975 to achieve all of these rates.)
979 The i960 configuration now includes an initial implementation of a
980 builtin simulator, contributed by Jim Wilson.
983 *** Changes in GDB-4.17:
985 * New native configurations
987 Alpha GNU/Linux alpha*-*-linux*
988 Unixware 2.x i[3456]86-unixware2*
989 Irix 6.x mips*-sgi-irix6*
990 PowerPC GNU/Linux powerpc-*-linux*
991 PowerPC Solaris powerpcle-*-solaris*
992 Sparc GNU/Linux sparc-*-linux*
993 Motorola sysV68 R3V7.1 m68k-motorola-sysv
997 Argonaut Risc Chip (ARC) arc-*-*
998 Hitachi H8/300S h8300*-*-*
999 Matsushita MN10200 w/simulator mn10200-*-*
1000 Matsushita MN10300 w/simulator mn10300-*-*
1001 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
1002 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
1003 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
1004 Mitsubishi D10V w/simulator d10v-*-*
1005 Mitsubishi M32R/D w/simulator m32r-*-elf*
1006 Tsqware Sparclet sparclet-*-*
1007 NEC V850 w/simulator v850-*-*
1009 * New debugging protocols
1011 ARM with RDI protocol arm*-*-*
1012 M68K with dBUG monitor m68*-*-{aout,coff,elf}
1013 DDB and LSI variants of PMON protocol mips*-*-*
1014 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
1015 PowerPC with SDS protocol powerpc{,le}-*-eabi
1016 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
1020 All configurations can now understand and use the DWARF 2 debugging
1021 format. The choice is automatic, if the symbol file contains DWARF 2
1026 GDB now includes basic Java language support. This support is
1027 only useful with Java compilers that produce native machine code.
1029 * solib-absolute-prefix and solib-search-path
1031 For SunOS and SVR4 shared libraries, you may now set the prefix for
1032 loading absolute shared library symbol files, and the search path for
1033 locating non-absolute shared library symbol files.
1035 * Live range splitting
1037 GDB can now effectively debug code for which GCC has performed live
1038 range splitting as part of its optimization. See gdb/doc/LRS for
1039 more details on the expected format of the stabs information.
1043 GDB's support for the GNU Hurd, including thread debugging, has been
1044 updated to work with current versions of the Hurd.
1048 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
1049 instruction set. ARM GDB automatically detects when Thumb
1050 instructions are in use, and adjusts disassembly and backtracing
1055 GDB's MIPS target configurations now handle the MIP16 16-bit
1060 GDB now includes support for overlays; if an executable has been
1061 linked such that multiple sections are based at the same address, GDB
1062 will decide which section to use for symbolic info. You can choose to
1063 control the decision manually, using overlay commands, or implement
1064 additional target-side support and use "overlay load-target" to bring
1065 in the overlay mapping. Do "help overlay" for more detail.
1069 The command "info symbol <address>" displays information about
1070 the symbol at the specified address.
1074 The standard remote protocol now includes an extension that allows
1075 asynchronous collection and display of trace data. This requires
1076 extensive support in the target-side debugging stub. Tracing mode
1077 includes a new interaction mode in GDB and new commands: see the
1078 file tracepoint.c for more details.
1082 Configurations for embedded MIPS now include a simulator contributed
1083 by Cygnus Solutions. The simulator supports the instruction sets
1084 of most MIPS variants.
1088 Sparc configurations may now include the ERC32 simulator contributed
1089 by the European Space Agency. The simulator is not built into
1090 Sparc targets by default; configure with --enable-sim to include it.
1094 For target configurations that may include multiple variants of a
1095 basic architecture (such as MIPS and SH), you may now set the
1096 architecture explicitly. "set arch" sets, "info arch" lists
1097 the possible architectures.
1099 *** Changes in GDB-4.16:
1101 * New native configurations
1103 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1104 M68K NetBSD m68k-*-netbsd*
1105 PowerPC AIX 4.x powerpc-*-aix*
1106 PowerPC MacOS powerpc-*-macos*
1107 PowerPC Windows NT powerpcle-*-cygwin32
1108 RS/6000 AIX 4.x rs6000-*-aix4*
1112 ARM with RDP protocol arm-*-*
1113 I960 with MON960 i960-*-coff
1114 MIPS VxWorks mips*-*-vxworks*
1115 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1116 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1118 Matra Sparclet sparclet-*-*
1122 The powerpc-eabi configuration now includes the PSIM simulator,
1123 contributed by Andrew Cagney, with assistance from Mike Meissner.
1124 PSIM is a very elaborate model of the PowerPC, including not only
1125 basic instruction set execution, but also details of execution unit
1126 performance and I/O hardware. See sim/ppc/README for more details.
1130 GDB now works with Solaris 2.5.
1132 * Windows 95/NT native
1134 GDB will now work as a native debugger on Windows 95 and Windows NT.
1135 To build it from source, you must use the "gnu-win32" environment,
1136 which uses a DLL to emulate enough of Unix to run the GNU tools.
1137 Further information, binaries, and sources are available at
1138 ftp.cygnus.com, under pub/gnu-win32.
1140 * dont-repeat command
1142 If a user-defined command includes the command `dont-repeat', then the
1143 command will not be repeated if the user just types return. This is
1144 useful if the command is time-consuming to run, so that accidental
1145 extra keystrokes don't run the same command many times.
1147 * Send break instead of ^C
1149 The standard remote protocol now includes an option to send a break
1150 rather than a ^C to the target in order to interrupt it. By default,
1151 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1153 * Remote protocol timeout
1155 The standard remote protocol includes a new variable `remotetimeout'
1156 that allows you to set the number of seconds before GDB gives up trying
1157 to read from the target. The default value is 2.
1159 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1161 By default GDB will automatically keep track of objects as they are
1162 loaded and unloaded by the dynamic linker. By using the command `set
1163 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1164 when shared library events occur, thus allowing you to set breakpoints
1165 in shared libraries which are explicitly loaded by the inferior.
1167 Note this feature does not work on hpux8. On hpux9 you must link
1168 /usr/lib/end.o into your program. This feature should work
1169 automatically on hpux10.
1171 * Irix 5.x hardware watchpoint support
1173 Irix 5 configurations now support the use of hardware watchpoints.
1175 * Mips protocol "SYN garbage limit"
1177 When debugging a Mips target using the `target mips' protocol, you
1178 may set the number of characters that GDB will ignore by setting
1179 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1180 every character. The default value is 1050.
1182 * Recording and replaying remote debug sessions
1184 If you set `remotelogfile' to the name of a file, gdb will write to it
1185 a recording of a remote debug session. This recording may then be
1186 replayed back to gdb using "gdbreplay". See gdbserver/README for
1187 details. This is useful when you have a problem with GDB while doing
1188 remote debugging; you can make a recording of the session and send it
1189 to someone else, who can then recreate the problem.
1191 * Speedups for remote debugging
1193 GDB includes speedups for downloading and stepping MIPS systems using
1194 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1195 and more efficient S-record downloading.
1197 * Memory use reductions and statistics collection
1199 GDB now uses less memory and reports statistics about memory usage.
1200 Try the `maint print statistics' command, for example.
1202 *** Changes in GDB-4.15:
1204 * Psymtabs for XCOFF
1206 The symbol reader for AIX GDB now uses partial symbol tables. This
1207 can greatly improve startup time, especially for large executables.
1209 * Remote targets use caching
1211 Remote targets now use a data cache to speed up communication with the
1212 remote side. The data cache could lead to incorrect results because
1213 it doesn't know about volatile variables, thus making it impossible to
1214 debug targets which use memory mapped I/O devices. `set remotecache
1215 off' turns the the data cache off.
1217 * Remote targets may have threads
1219 The standard remote protocol now includes support for multiple threads
1220 in the target system, using new protocol commands 'H' and 'T'. See
1221 gdb/remote.c for details.
1225 If GDB is configured with `--enable-netrom', then it will include
1226 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1227 acts as though it is a bank of ROM on the target board, but you can
1228 write into it over the network. GDB's support consists only of
1229 support for fast loading into the emulated ROM; to debug, you must use
1230 another protocol, such as standard remote protocol. The usual
1231 sequence is something like
1233 target nrom <netrom-hostname>
1235 target remote <netrom-hostname>:1235
1239 GDB now includes support for the Apple Macintosh, as a host only. It
1240 may be run as either an MPW tool or as a standalone application, and
1241 it can debug through the serial port. All the usual GDB commands are
1242 available, but to the target command, you must supply "serial" as the
1243 device type instead of "/dev/ttyXX". See mpw-README in the main
1244 directory for more information on how to build. The MPW configuration
1245 scripts */mpw-config.in support only a few targets, and only the
1246 mips-idt-ecoff target has been tested.
1250 GDB configuration now uses autoconf. This is not user-visible,
1251 but does simplify configuration and building.
1255 GDB now supports hpux10.
1257 *** Changes in GDB-4.14:
1259 * New native configurations
1261 x86 FreeBSD i[345]86-*-freebsd
1262 x86 NetBSD i[345]86-*-netbsd
1263 NS32k NetBSD ns32k-*-netbsd
1264 Sparc NetBSD sparc-*-netbsd
1268 A29K VxWorks a29k-*-vxworks
1269 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1270 CPU32 EST-300 emulator m68*-*-est*
1271 PowerPC ELF powerpc-*-elf
1274 * Alpha OSF/1 support for procfs
1276 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1277 possible to attach to running processes. As the mounting of the /proc
1278 filesystem is optional on the Alpha, GDB automatically determines
1279 the availability of /proc during startup. This can lead to problems
1280 if /proc is unmounted after GDB has been started.
1282 * Arguments to user-defined commands
1284 User commands may accept up to 10 arguments separated by whitespace.
1285 Arguments are accessed within the user command via $arg0..$arg9. A
1288 print $arg0 + $arg1 + $arg2
1290 To execute the command use:
1293 Defines the command "adder" which prints the sum of its three arguments.
1294 Note the arguments are text substitutions, so they may reference variables,
1295 use complex expressions, or even perform inferior function calls.
1297 * New `if' and `while' commands
1299 This makes it possible to write more sophisticated user-defined
1300 commands. Both commands take a single argument, which is the
1301 expression to evaluate, and must be followed by the commands to
1302 execute, one per line, if the expression is nonzero, the list being
1303 terminated by the word `end'. The `if' command list may include an
1304 `else' word, which causes the following commands to be executed only
1305 if the expression is zero.
1307 * Fortran source language mode
1309 GDB now includes partial support for Fortran 77. It will recognize
1310 Fortran programs and can evaluate a subset of Fortran expressions, but
1311 variables and functions may not be handled correctly. GDB will work
1312 with G77, but does not yet know much about symbols emitted by other
1315 * Better HPUX support
1317 Most debugging facilities now work on dynamic executables for HPPAs
1318 running hpux9 or later. You can attach to running dynamically linked
1319 processes, but by default the dynamic libraries will be read-only, so
1320 for instance you won't be able to put breakpoints in them. To change
1321 that behavior do the following before running the program:
1327 This will cause the libraries to be mapped private and read-write.
1328 To revert to the normal behavior, do this:
1334 You cannot set breakpoints or examine data in the library until after
1335 the library is loaded if the function/data symbols do not have
1338 GDB can now also read debug symbols produced by the HP C compiler on
1339 HPPAs (sorry, no C++, Fortran or 68k support).
1341 * Target byte order now dynamically selectable
1343 You can choose which byte order to use with a target system, via the
1344 commands "set endian big" and "set endian little", and you can see the
1345 current setting by using "show endian". You can also give the command
1346 "set endian auto", in which case GDB will use the byte order
1347 associated with the executable. Currently, only embedded MIPS
1348 configurations support dynamic selection of target byte order.
1350 * New DOS host serial code
1352 This version uses DPMI interrupts to handle buffered I/O, so you
1353 no longer need to run asynctsr when debugging boards connected to
1356 *** Changes in GDB-4.13:
1358 * New "complete" command
1360 This lists all the possible completions for the rest of the line, if it
1361 were to be given as a command itself. This is intended for use by emacs.
1363 * Trailing space optional in prompt
1365 "set prompt" no longer adds a space for you after the prompt you set. This
1366 allows you to set a prompt which ends in a space or one that does not.
1368 * Breakpoint hit counts
1370 "info break" now displays a count of the number of times the breakpoint
1371 has been hit. This is especially useful in conjunction with "ignore"; you
1372 can ignore a large number of breakpoint hits, look at the breakpoint info
1373 to see how many times the breakpoint was hit, then run again, ignoring one
1374 less than that number, and this will get you quickly to the last hit of
1377 * Ability to stop printing at NULL character
1379 "set print null-stop" will cause GDB to stop printing the characters of
1380 an array when the first NULL is encountered. This is useful when large
1381 arrays actually contain only short strings.
1383 * Shared library breakpoints
1385 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1386 breakpoints in shared libraries before the executable is run.
1388 * Hardware watchpoints
1390 There is a new hardware breakpoint for the watch command for sparclite
1391 targets. See gdb/sparclite/hw_breakpoint.note.
1393 Hardware watchpoints are also now supported under GNU/Linux.
1397 Annotations have been added. These are for use with graphical interfaces,
1398 and are still experimental. Currently only gdba.el uses these.
1400 * Improved Irix 5 support
1402 GDB now works properly with Irix 5.2.
1404 * Improved HPPA support
1406 GDB now works properly with the latest GCC and GAS.
1408 * New native configurations
1410 Sequent PTX4 i[34]86-sequent-ptx4
1411 HPPA running OSF/1 hppa*-*-osf*
1412 Atari TT running SVR4 m68*-*-sysv4*
1413 RS/6000 LynxOS rs6000-*-lynxos*
1417 OS/9000 i[34]86-*-os9k
1418 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1421 * Hitachi SH7000 and E7000-PC ICE support
1423 There is now support for communicating with the Hitachi E7000-PC ICE.
1424 This is available automatically when GDB is configured for the SH.
1428 As usual, a variety of small fixes and improvements, both generic
1429 and configuration-specific. See the ChangeLog for more detail.
1431 *** Changes in GDB-4.12:
1433 * Irix 5 is now supported
1437 GDB-4.12 on the HPPA has a number of changes which make it unable
1438 to debug the output from the currently released versions of GCC and
1439 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1440 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1441 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1444 *** Changes in GDB-4.11:
1446 * User visible changes:
1450 The "set remotedebug" option is now consistent between the mips remote
1451 target, remote targets using the gdb-specific protocol, UDI (AMD's
1452 debug protocol for the 29k) and the 88k bug monitor. It is now an
1453 integer specifying a debug level (normally 0 or 1, but 2 means more
1454 debugging info for the mips target).
1456 * DEC Alpha native support
1458 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1459 debug info, but GDB works fairly well with the DEC compiler and should
1460 work with a future GCC release. See the README file for a few
1461 Alpha-specific notes.
1463 * Preliminary thread implementation
1465 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1467 * LynxOS native and target support for 386
1469 This release has been hosted on LynxOS 2.2, and also can be configured
1470 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1473 * Improvements in C++ mangling/demangling.
1475 This release has much better g++ debugging, specifically in name
1476 mangling/demangling, virtual function calls, print virtual table,
1477 call methods, ...etc.
1479 *** Changes in GDB-4.10:
1481 * User visible changes:
1483 Remote debugging using the GDB-specific (`target remote') protocol now
1484 supports the `load' command. This is only useful if you have some
1485 other way of getting the stub to the target system, and you can put it
1486 somewhere in memory where it won't get clobbered by the download.
1488 Filename completion now works.
1490 When run under emacs mode, the "info line" command now causes the
1491 arrow to point to the line specified. Also, "info line" prints
1492 addresses in symbolic form (as well as hex).
1494 All vxworks based targets now support a user settable option, called
1495 vxworks-timeout. This option represents the number of seconds gdb
1496 should wait for responses to rpc's. You might want to use this if
1497 your vxworks target is, perhaps, a slow software simulator or happens
1498 to be on the far side of a thin network line.
1502 This release contains support for using a DEC alpha as a GDB host for
1503 cross debugging. Native alpha debugging is not supported yet.
1506 *** Changes in GDB-4.9:
1510 This is the first GDB release which is accompanied by a matching testsuite.
1511 The testsuite requires installation of dejagnu, which should be available
1512 via ftp from most sites that carry GNU software.
1516 'Cfront' style demangling has had its name changed to 'ARM' style, to
1517 emphasize that it was written from the specifications in the C++ Annotated
1518 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1519 disclaimers, it still generated too much confusion with users attempting to
1520 use gdb with AT&T cfront.
1524 GDB now uses a standard remote interface to a simulator library.
1525 So far, the library contains simulators for the Zilog Z8001/2, the
1526 Hitachi H8/300, H8/500 and Super-H.
1528 * New targets supported
1530 H8/300 simulator h8300-hitachi-hms or h8300hms
1531 H8/500 simulator h8500-hitachi-hms or h8500hms
1532 SH simulator sh-hitachi-hms or sh
1533 Z8000 simulator z8k-zilog-none or z8ksim
1534 IDT MIPS board over serial line mips-idt-ecoff
1536 Cross-debugging to GO32 targets is supported. It requires a custom
1537 version of the i386-stub.c module which is integrated with the
1538 GO32 memory extender.
1540 * New remote protocols
1542 MIPS remote debugging protocol.
1544 * New source languages supported
1546 This version includes preliminary support for Chill, a Pascal like language
1547 used by telecommunications companies. Chill support is also being integrated
1548 into the GNU compiler, but we don't know when it will be publically available.
1551 *** Changes in GDB-4.8:
1553 * HP Precision Architecture supported
1555 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1556 version of this support was available as a set of patches from the
1557 University of Utah. GDB does not support debugging of programs
1558 compiled with the HP compiler, because HP will not document their file
1559 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1560 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1562 Many problems in the preliminary version have been fixed.
1564 * Faster and better demangling
1566 We have improved template demangling and fixed numerous bugs in the GNU style
1567 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1568 character types (wchar_t) are now supported. Demangling of each symbol is now
1569 only done once, and is cached when the symbol table for a file is read in.
1570 This results in a small increase in memory usage for C programs, a moderate
1571 increase in memory usage for C++ programs, and a fantastic speedup in
1574 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1575 from the specifications in the Annotated Reference Manual, which AT&T's
1576 compiler does not actually implement.
1578 * G++ multiple inheritance compiler problem
1580 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1581 inheritance lattices was reworked to properly discover ambiguities. We
1582 recently found an example which causes this new algorithm to fail in a
1583 very subtle way, producing bad debug information for those classes.
1584 The file 'gcc.patch' (in this directory) can be applied to gcc to
1585 circumvent the problem. A future GCC release will contain a complete
1588 The previous G++ debug info problem (mentioned below for the gdb-4.7
1589 release) is fixed in gcc version 2.3.2.
1591 * Improved configure script
1593 The `configure' script will now attempt to guess your system type if
1594 you don't supply a host system type. The old scheme of supplying a
1595 host system triplet is preferable over using this. All the magic is
1596 done in the new `config.guess' script. Examine it for details.
1598 We have also brought our configure script much more in line with the FSF's
1599 version. It now supports the --with-xxx options. In particular,
1600 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1601 The resulting GDB will not be able to read arbitrary object file formats --
1602 only the format ``expected'' to be used on the configured target system.
1603 We hope to make this the default in a future release.
1605 * Documentation improvements
1607 There's new internal documentation on how to modify GDB, and how to
1608 produce clean changes to the code. We implore people to read it
1609 before submitting changes.
1611 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1612 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1613 `info' files are also provided. To build `info' files from scratch,
1614 you will need the latest `makeinfo' release, which will be available in
1615 a future texinfo-X.Y release.
1617 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1618 We're not sure exactly which versions have this problem, but it has
1619 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1620 or better. If that isn't possible, there is a patch in
1621 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1622 around this problem.
1626 GDB now supports array constants that can be used in expressions typed in by
1627 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1628 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1631 The new directory `gdb/sparclite' contains a program that demonstrates
1632 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1634 * New native hosts supported
1636 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1637 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1639 * New targets supported
1641 AMD 29k family via UDI a29k-amd-udi or udi29k
1643 * New file formats supported
1645 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1646 HPUX core files, and SCO 3.2v2 core files.
1650 Attaching to processes now works again; thanks for the many bug reports.
1652 We have also stomped on a bunch of core dumps caused by
1653 printf_filtered("%s") problems.
1655 We eliminated a copyright problem on the rpc and ptrace header files
1656 for VxWorks, which was discovered at the last minute during the 4.7
1657 release. You should now be able to build a VxWorks GDB.
1659 You can now interrupt gdb while an attached process is running. This
1660 will cause the attached process to stop, and give control back to GDB.
1662 We fixed problems caused by using too many file descriptors
1663 for reading symbols from object files and libraries. This was
1664 especially a problem for programs that used many (~100) shared
1667 The `step' command now only enters a subroutine if there is line number
1668 information for the subroutine. Otherwise it acts like the `next'
1669 command. Previously, `step' would enter subroutines if there was
1670 any debugging information about the routine. This avoids problems
1671 when using `cc -g1' on MIPS machines.
1673 * Internal improvements
1675 GDB's internal interfaces have been improved to make it easier to support
1676 debugging of multiple languages in the future.
1678 GDB now uses a common structure for symbol information internally.
1679 Minimal symbols (derived from linkage symbols in object files), partial
1680 symbols (from a quick scan of debug information), and full symbols
1681 contain a common subset of information, making it easier to write
1682 shared code that handles any of them.
1684 * New command line options
1686 We now accept --silent as an alias for --quiet.
1690 The memory-mapped-malloc library is now licensed under the GNU Library
1691 General Public License.
1693 *** Changes in GDB-4.7:
1695 * Host/native/target split
1697 GDB has had some major internal surgery to untangle the support for
1698 hosts and remote targets. Now, when you configure GDB for a remote
1699 target, it will no longer load in all of the support for debugging
1700 local programs on the host. When fully completed and tested, this will
1701 ensure that arbitrary host/target combinations are possible.
1703 The primary conceptual shift is to separate the non-portable code in
1704 GDB into three categories. Host specific code is required any time GDB
1705 is compiled on that host, regardless of the target. Target specific
1706 code relates to the peculiarities of the target, but can be compiled on
1707 any host. Native specific code is everything else: it can only be
1708 built when the host and target are the same system. Child process
1709 handling and core file support are two common `native' examples.
1711 GDB's use of /proc for controlling Unix child processes is now cleaner.
1712 It has been split out into a single module under the `target_ops' vector,
1713 plus two native-dependent functions for each system that uses /proc.
1715 * New hosts supported
1717 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1718 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1719 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1721 * New targets supported
1723 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1724 68030 and CPU32 m68030-*-*, m68332-*-*
1726 * New native hosts supported
1728 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1729 (386bsd is not well tested yet)
1730 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1732 * New file formats supported
1734 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1735 supports reading of `a.out.adobe' object files, which are an a.out
1736 format extended with minimal information about multiple sections.
1740 `show copying' is the same as the old `info copying'.
1741 `show warranty' is the same as `info warrantee'.
1742 These were renamed for consistency. The old commands continue to work.
1744 `info handle' is a new alias for `info signals'.
1746 You can now define pre-command hooks, which attach arbitrary command
1747 scripts to any command. The commands in the hook will be executed
1748 prior to the user's command. You can also create a hook which will be
1749 executed whenever the program stops. See gdb.texinfo.
1753 We now deal with Cfront style name mangling, and can even extract type
1754 info from mangled symbols. GDB can automatically figure out which
1755 symbol mangling style your C++ compiler uses.
1757 Calling of methods and virtual functions has been improved as well.
1761 The crash that occured when debugging Sun Ansi-C compiled binaries is
1762 fixed. This was due to mishandling of the extra N_SO stabs output
1765 We also finally got Ultrix 4.2 running in house, and fixed core file
1766 support, with help from a dozen people on the net.
1768 John M. Farrell discovered that the reason that single-stepping was so
1769 slow on all of the Mips based platforms (primarily SGI and DEC) was
1770 that we were trying to demangle and lookup a symbol used for internal
1771 purposes on every instruction that was being stepped through. Changing
1772 the name of that symbol so that it couldn't be mistaken for a C++
1773 mangled symbol sped things up a great deal.
1775 Rich Pixley sped up symbol lookups in general by getting much smarter
1776 about when C++ symbol mangling is necessary. This should make symbol
1777 completion (TAB on the command line) much faster. It's not as fast as
1778 we'd like, but it's significantly faster than gdb-4.6.
1782 A new user controllable variable 'call_scratch_address' can
1783 specify the location of a scratch area to be used when GDB
1784 calls a function in the target. This is necessary because the
1785 usual method of putting the scratch area on the stack does not work
1786 in systems that have separate instruction and data spaces.
1788 We integrated changes to support the 29k UDI (Universal Debugger
1789 Interface), but discovered at the last minute that we didn't have all
1790 of the appropriate copyright paperwork. We are working with AMD to
1791 resolve this, and hope to have it available soon.
1795 We have sped up the remote serial line protocol, especially for targets
1796 with lots of registers. It now supports a new `expedited status' ('T')
1797 message which can be used in place of the existing 'S' status message.
1798 This allows the remote stub to send only the registers that GDB
1799 needs to make a quick decision about single-stepping or conditional
1800 breakpoints, eliminating the need to fetch the entire register set for
1801 each instruction being stepped through.
1803 The GDB remote serial protocol now implements a write-through cache for
1804 registers, only re-reading the registers if the target has run.
1806 There is also a new remote serial stub for SPARC processors. You can
1807 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1808 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1809 processor with a serial port.
1813 Configure.in files have become much easier to read and modify. A new
1814 `table driven' format makes it more obvious what configurations are
1815 supported, and what files each one uses.
1819 There is a new opcodes library which will eventually contain all of the
1820 disassembly routines and opcode tables. At present, it only contains
1821 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1822 disassembler (binutils/objdump) to share these routines.
1824 The libiberty library is now copylefted under the GNU Library General
1825 Public License. This allows more liberal use, and was done so libg++
1826 can use it. This makes no difference to GDB, since the Library License
1827 grants all the rights from the General Public License.
1831 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1832 reference to the stabs symbol info used by the debugger. It is (as far
1833 as we know) the only published document on this fascinating topic. We
1834 encourage you to read it, compare it to the stabs information on your
1835 system, and send improvements on the document in general (to
1836 bug-gdb@prep.ai.mit.edu).
1838 And, of course, many bugs have been fixed.
1841 *** Changes in GDB-4.6:
1843 * Better support for C++ function names
1845 GDB now accepts as input the "demangled form" of C++ overloaded function
1846 names and member function names, and can do command completion on such names
1847 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1848 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1849 Make use of command completion, it is your friend.
1851 GDB also now accepts a variety of C++ mangled symbol formats. They are
1852 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1853 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1854 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1855 for the list of formats.
1857 * G++ symbol mangling problem
1859 Recent versions of gcc have a bug in how they emit debugging information for
1860 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1861 directory) can be applied to gcc to fix the problem. Alternatively, if you
1862 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1863 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1864 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1867 * New 'maintenance' command
1869 All of the commands related to hacking GDB internals have been moved out of
1870 the main command set, and now live behind the 'maintenance' command. This
1871 can also be abbreviated as 'mt'. The following changes were made:
1873 dump-me -> maintenance dump-me
1874 info all-breakpoints -> maintenance info breakpoints
1875 printmsyms -> maintenance print msyms
1876 printobjfiles -> maintenance print objfiles
1877 printpsyms -> maintenance print psymbols
1878 printsyms -> maintenance print symbols
1880 The following commands are new:
1882 maintenance demangle Call internal GDB demangler routine to
1883 demangle a C++ link name and prints the result.
1884 maintenance print type Print a type chain for a given symbol
1886 * Change to .gdbinit file processing
1888 We now read the $HOME/.gdbinit file before processing the argv arguments
1889 (e.g. reading symbol files or core files). This allows global parameters to
1890 be set, which will apply during the symbol reading. The ./.gdbinit is still
1891 read after argv processing.
1893 * New hosts supported
1895 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1897 GNU/Linux support i386-unknown-linux or linux
1899 We are also including code to support the HP/PA running BSD and HPUX. This
1900 is almost guaranteed not to work, as we didn't have time to test or build it
1901 for this release. We are including it so that the more adventurous (or
1902 masochistic) of you can play with it. We also had major problems with the
1903 fact that the compiler that we got from HP doesn't support the -g option.
1906 * New targets supported
1908 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1910 * More smarts about finding #include files
1912 GDB now remembers the compilation directory for all include files, and for
1913 all files from which C is generated (like yacc and lex sources). This
1914 greatly improves GDB's ability to find yacc/lex sources, and include files,
1915 especially if you are debugging your program from a directory different from
1916 the one that contains your sources.
1918 We also fixed a bug which caused difficulty with listing and setting
1919 breakpoints in include files which contain C code. (In the past, you had to
1920 try twice in order to list an include file that you hadn't looked at before.)
1922 * Interesting infernals change
1924 GDB now deals with arbitrary numbers of sections, where the symbols for each
1925 section must be relocated relative to that section's landing place in the
1926 target's address space. This work was needed to support ELF with embedded
1927 stabs used by Solaris-2.0.
1929 * Bug fixes (of course!)
1931 There have been loads of fixes for the following things:
1932 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1933 i960, stabs, DOS(GO32), procfs, etc...
1935 See the ChangeLog for details.
1937 *** Changes in GDB-4.5:
1939 * New machines supported (host and target)
1941 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1943 SGI Irix-4.x mips-sgi-irix4 or iris4
1945 * New malloc package
1947 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1948 Mmalloc is capable of handling mutiple heaps of memory. It is also
1949 capable of saving a heap to a file, and then mapping it back in later.
1950 This can be used to greatly speedup the startup of GDB by using a
1951 pre-parsed symbol table which lives in a mmalloc managed heap. For
1952 more details, please read mmalloc/mmalloc.texi.
1956 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1957 'help info proc' for details.
1959 * MIPS ecoff symbol table format
1961 The code that reads MIPS symbol table format is now supported on all hosts.
1962 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1965 * File name changes for MS-DOS
1967 Many files in the config directories have been renamed to make it easier to
1968 support GDB on MS-DOSe systems (which have very restrictive file name
1969 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1970 environment) is close to working but has some remaining problems. Note
1971 that debugging of DOS programs is not supported, due to limitations
1972 in the ``operating system'', but it can be used to host cross-debugging.
1974 * Cross byte order fixes
1976 Many fixes have been made to support cross debugging of Sparc and MIPS
1977 targets from hosts whose byte order differs.
1979 * New -mapped and -readnow options
1981 If memory-mapped files are available on your system through the 'mmap'
1982 system call, you can use the -mapped option on the `file' or
1983 `symbol-file' commands to cause GDB to write the symbols from your
1984 program into a reusable file. If the program you are debugging is
1985 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1986 Future GDB debugging sessions will notice the presence of this file,
1987 and will quickly map in symbol information from it, rather than reading
1988 the symbol table from the executable program. Using the '-mapped'
1989 option in a GDB `file' or `symbol-file' command has the same effect as
1990 starting GDB with the '-mapped' command-line option.
1992 You can cause GDB to read the entire symbol table immediately by using
1993 the '-readnow' option with any of the commands that load symbol table
1994 information (or on the GDB command line). This makes the command
1995 slower, but makes future operations faster.
1997 The -mapped and -readnow options are typically combined in order to
1998 build a `fred.syms' file that contains complete symbol information.
1999 A simple GDB invocation to do nothing but build a `.syms' file for future
2002 gdb -batch -nx -mapped -readnow programname
2004 The `.syms' file is specific to the host machine on which GDB is run.
2005 It holds an exact image of GDB's internal symbol table. It cannot be
2006 shared across multiple host platforms.
2008 * longjmp() handling
2010 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
2011 siglongjmp() without losing control. This feature has not yet been ported to
2012 all systems. It currently works on many 386 platforms, all MIPS-based
2013 platforms (SGI, DECstation, etc), and Sun3/4.
2017 Preliminary work has been put in to support the new Solaris OS from Sun. At
2018 this time, it can control and debug processes, but it is not capable of
2023 As always, many many bug fixes. The major areas were with g++, and mipsread.
2024 People using the MIPS-based platforms should experience fewer mysterious
2025 crashes and trashed symbol tables.
2027 *** Changes in GDB-4.4:
2029 * New machines supported (host and target)
2031 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2033 BSD Reno on Vax vax-dec-bsd
2034 Ultrix on Vax vax-dec-ultrix
2036 * New machines supported (target)
2038 AMD 29000 embedded, using EBMON a29k-none-none
2042 GDB continues to improve its handling of C++. `References' work better.
2043 The demangler has also been improved, and now deals with symbols mangled as
2044 per the Annotated C++ Reference Guide.
2046 GDB also now handles `stabs' symbol information embedded in MIPS
2047 `ecoff' symbol tables. Since the ecoff format was not easily
2048 extensible to handle new languages such as C++, this appeared to be a
2049 good way to put C++ debugging info into MIPS binaries. This option
2050 will be supported in the GNU C compiler, version 2, when it is
2053 * New features for SVR4
2055 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2056 shared libraries. Debugging dynamically linked programs should present
2057 only minor differences from debugging statically linked programs.
2059 The `info proc' command will print out information about any process
2060 on an SVR4 system (including the one you are debugging). At the moment,
2061 it prints the address mappings of the process.
2063 If you bring up GDB on another SVR4 system, please send mail to
2064 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2066 * Better dynamic linking support in SunOS
2068 Reading symbols from shared libraries which contain debugging symbols
2069 now works properly. However, there remain issues such as automatic
2070 skipping of `transfer vector' code during function calls, which
2071 make it harder to debug code in a shared library, than to debug the
2072 same code linked statically.
2076 GDB is now using the latest `getopt' routines from the FSF. This
2077 version accepts the -- prefix for options with long names. GDB will
2078 continue to accept the old forms (-option and +option) as well.
2079 Various single letter abbreviations for options have been explicity
2080 added to the option table so that they won't get overshadowed in the
2081 future by other options that begin with the same letter.
2085 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2086 Many assorted bugs have been handled. Many more remain to be handled.
2087 See the various ChangeLog files (primarily in gdb and bfd) for details.
2090 *** Changes in GDB-4.3:
2092 * New machines supported (host and target)
2094 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2095 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2096 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2098 * Almost SCO Unix support
2100 We had hoped to support:
2101 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2102 (except for core file support), but we discovered very late in the release
2103 that it has problems with process groups that render gdb unusable. Sorry
2104 about that. I encourage people to fix it and post the fixes.
2106 * Preliminary ELF and DWARF support
2108 GDB can read ELF object files on System V Release 4, and can handle
2109 debugging records for C, in DWARF format, in ELF files. This support
2110 is preliminary. If you bring up GDB on another SVR4 system, please
2111 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2116 GDB now uses the latest `readline' library. One user-visible change
2117 is that two tabs will list possible command completions, which previously
2118 required typing M-? (meta-question mark, or ESC ?).
2122 The `stepi' bug that many of you noticed has been squashed.
2123 Many bugs in C++ have been handled. Many more remain to be handled.
2124 See the various ChangeLog files (primarily in gdb and bfd) for details.
2126 * State of the MIPS world (in case you wondered):
2128 GDB can understand the symbol tables emitted by the compilers
2129 supplied by most vendors of MIPS-based machines, including DEC. These
2130 symbol tables are in a format that essentially nobody else uses.
2132 Some versions of gcc come with an assembler post-processor called
2133 mips-tfile. This program is required if you want to do source-level
2134 debugging of gcc-compiled programs. I believe FSF does not ship
2135 mips-tfile with gcc version 1, but it will eventually come with gcc
2138 Debugging of g++ output remains a problem. g++ version 1.xx does not
2139 really support it at all. (If you're lucky, you should be able to get
2140 line numbers and stack traces to work, but no parameters or local
2141 variables.) With some work it should be possible to improve the
2144 When gcc version 2 is released, you will have somewhat better luck.
2145 However, even then you will get confusing results for inheritance and
2148 We will eventually provide full debugging of g++ output on
2149 DECstations. This will probably involve some kind of stabs-in-ecoff
2150 encapulation, but the details have not been worked out yet.
2153 *** Changes in GDB-4.2:
2155 * Improved configuration
2157 Only one copy of `configure' exists now, and it is not self-modifying.
2158 Porting BFD is simpler.
2162 The `step' and `next' commands now only stop at the first instruction
2163 of a source line. This prevents the multiple stops that used to occur
2164 in switch statements, for-loops, etc. `Step' continues to stop if a
2165 function that has debugging information is called within the line.
2169 Lots of small bugs fixed. More remain.
2171 * New host supported (not target)
2173 Intel 386 PC clone running Mach i386-none-mach
2176 *** Changes in GDB-4.1:
2178 * Multiple source language support
2180 GDB now has internal scaffolding to handle several source languages.
2181 It determines the type of each source file from its filename extension,
2182 and will switch expression parsing and number formatting to match the
2183 language of the function in the currently selected stack frame.
2184 You can also specifically set the language to be used, with
2185 `set language c' or `set language modula-2'.
2189 GDB now has preliminary support for the GNU Modula-2 compiler,
2190 currently under development at the State University of New York at
2191 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2192 continue through the fall of 1991 and into 1992.
2194 Other Modula-2 compilers are currently not supported, and attempting to
2195 debug programs compiled with them will likely result in an error as the
2196 symbol table is read. Feel free to work on it, though!
2198 There are hooks in GDB for strict type checking and range checking,
2199 in the `Modula-2 philosophy', but they do not currently work.
2203 GDB can now write to executable and core files (e.g. patch
2204 a variable's value). You must turn this switch on, specify
2205 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2206 by assigning a new value to a variable. Modifications take
2209 * Automatic SunOS shared library reading
2211 When you run your program, GDB automatically determines where its
2212 shared libraries (if any) have been loaded, and reads their symbols.
2213 The `share' command is no longer needed. This also works when
2214 examining core files.
2218 You can specify the number of lines that the `list' command shows.
2221 * New machines supported (host and target)
2223 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2224 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2225 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2227 * New hosts supported (not targets)
2229 IBM RT/PC: romp-ibm-aix or rtpc
2231 * New targets supported (not hosts)
2233 AMD 29000 embedded with COFF a29k-none-coff
2234 AMD 29000 embedded with a.out a29k-none-aout
2235 Ultracomputer remote kernel debug a29k-nyu-kern
2237 * New remote interfaces
2243 *** Changes in GDB-4.0:
2247 Wide output is wrapped at good places to make the output more readable.
2249 Gdb now supports cross-debugging from a host machine of one type to a
2250 target machine of another type. Communication with the target system
2251 is over serial lines. The ``target'' command handles connecting to the
2252 remote system; the ``load'' command will download a program into the
2253 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2254 also supports debugging of realtime processes running under VxWorks,
2255 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2256 stub on the target system.
2258 New CPUs supported include the AMD 29000 and Intel 960.
2260 GDB now reads object files and symbol tables via a ``binary file''
2261 library, which allows a single copy of GDB to debug programs of multiple
2262 object file types such as a.out and coff.
2264 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2265 refcard.dvi and refcard.ps are available to format it).
2268 * Control-Variable user interface simplified
2270 All variables that control the operation of the debugger can be set
2271 by the ``set'' command, and displayed by the ``show'' command.
2273 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2274 ``Show prompt'' produces the response:
2275 Gdb's prompt is new-gdb=>.
2277 What follows are the NEW set commands. The command ``help set'' will
2278 print a complete list of old and new set commands. ``help set FOO''
2279 will give a longer description of the variable FOO. ``show'' will show
2280 all of the variable descriptions and their current settings.
2282 confirm on/off: Enables warning questions for operations that are
2283 hard to recover from, e.g. rerunning the program while
2284 it is already running. Default is ON.
2286 editing on/off: Enables EMACS style command line editing
2287 of input. Previous lines can be recalled with
2288 control-P, the current line can be edited with control-B,
2289 you can search for commands with control-R, etc.
2292 history filename NAME: NAME is where the gdb command history
2293 will be stored. The default is .gdb_history,
2294 or the value of the environment variable
2297 history size N: The size, in commands, of the command history. The
2298 default is 256, or the value of the environment variable
2301 history save on/off: If this value is set to ON, the history file will
2302 be saved after exiting gdb. If set to OFF, the
2303 file will not be saved. The default is OFF.
2305 history expansion on/off: If this value is set to ON, then csh-like
2306 history expansion will be performed on
2307 command line input. The default is OFF.
2309 radix N: Sets the default radix for input and output. It can be set
2310 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2311 in the current radix, so "set radix 10" is always a no-op.
2313 height N: This integer value is the number of lines on a page. Default
2314 is 24, the current `stty rows'' setting, or the ``li#''
2315 setting from the termcap entry matching the environment
2318 width N: This integer value is the number of characters on a line.
2319 Default is 80, the current `stty cols'' setting, or the ``co#''
2320 setting from the termcap entry matching the environment
2323 Note: ``set screensize'' is obsolete. Use ``set height'' and
2324 ``set width'' instead.
2326 print address on/off: Print memory addresses in various command displays,
2327 such as stack traces and structure values. Gdb looks
2328 more ``symbolic'' if you turn this off; it looks more
2329 ``machine level'' with it on. Default is ON.
2331 print array on/off: Prettyprint arrays. New convenient format! Default
2334 print demangle on/off: Print C++ symbols in "source" form if on,
2337 print asm-demangle on/off: Same, for assembler level printouts
2340 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2343 * Support for Epoch Environment.
2345 The epoch environment is a version of Emacs v18 with windowing. One
2346 new command, ``inspect'', is identical to ``print'', except that if you
2347 are running in the epoch environment, the value is printed in its own
2351 * Support for Shared Libraries
2353 GDB can now debug programs and core files that use SunOS shared libraries.
2354 Symbols from a shared library cannot be referenced
2355 before the shared library has been linked with the program (this
2356 happens after you type ``run'' and before the function main() is entered).
2357 At any time after this linking (including when examining core files
2358 from dynamically linked programs), gdb reads the symbols from each
2359 shared library when you type the ``sharedlibrary'' command.
2360 It can be abbreviated ``share''.
2362 sharedlibrary REGEXP: Load shared object library symbols for files
2363 matching a unix regular expression. No argument
2364 indicates to load symbols for all shared libraries.
2366 info sharedlibrary: Status of loaded shared libraries.
2371 A watchpoint stops execution of a program whenever the value of an
2372 expression changes. Checking for this slows down execution
2373 tremendously whenever you are in the scope of the expression, but is
2374 quite useful for catching tough ``bit-spreader'' or pointer misuse
2375 problems. Some machines such as the 386 have hardware for doing this
2376 more quickly, and future versions of gdb will use this hardware.
2378 watch EXP: Set a watchpoint (breakpoint) for an expression.
2380 info watchpoints: Information about your watchpoints.
2382 delete N: Deletes watchpoint number N (same as breakpoints).
2383 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2384 enable N: Re-enables watchpoint number N (same as breakpoints).
2387 * C++ multiple inheritance
2389 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2392 * C++ exception handling
2394 Gdb now supports limited C++ exception handling. Besides the existing
2395 ability to breakpoint on an exception handler, gdb can breakpoint on
2396 the raising of an exception (before the stack is peeled back to the
2399 catch FOO: If there is a FOO exception handler in the dynamic scope,
2400 set a breakpoint to catch exceptions which may be raised there.
2401 Multiple exceptions (``catch foo bar baz'') may be caught.
2403 info catch: Lists all exceptions which may be caught in the
2404 current stack frame.
2407 * Minor command changes
2409 The command ``call func (arg, arg, ...)'' now acts like the print
2410 command, except it does not print or save a value if the function's result
2411 is void. This is similar to dbx usage.
2413 The ``up'' and ``down'' commands now always print the frame they end up
2414 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2415 frames without printing.
2417 * New directory command
2419 'dir' now adds directories to the FRONT of the source search path.
2420 The path starts off empty. Source files that contain debug information
2421 about the directory in which they were compiled can be found even
2422 with an empty path; Sun CC and GCC include this information. If GDB can't
2423 find your source file in the current directory, type "dir .".
2425 * Configuring GDB for compilation
2427 For normal use, type ``./configure host''. See README or gdb.texinfo
2430 GDB now handles cross debugging. If you are remotely debugging between
2431 two different machines, type ``./configure host -target=targ''.
2432 Host is the machine where GDB will run; targ is the machine
2433 where the program that you are debugging will run.