1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.0:
6 * New native configurations
8 NetBSD/amd64 x86_64-*-netbsd*
10 * New debugging protocols
12 M32R with SDI protocol m32r-*-elf*
14 * "set prompt-escape-char" command deleted.
16 The command "set prompt-escape-char" has been deleted. This command,
17 and its very obscure effet on GDB's prompt, was never documented,
18 tested, nor mentioned in the NEWS file.
20 * REMOVED configurations and files
22 SGI Irix-4.x mips-sgi-irix4 or iris4
23 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
24 Z8000 simulator z8k-zilog-none or z8ksim
25 Matsushita MN10200 w/simulator mn10200-*-*
26 H8/500 simulator h8500-hitachi-hms or h8500hms
27 HP/PA running BSD hppa*-*-bsd*
28 HP/PA running OSF/1 hppa*-*-osf*
29 HP/PA Pro target hppa*-*-pro*
30 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
31 Sequent family i[3456]86-sequent-sysv4*
32 i[3456]86-sequent-sysv*
33 i[3456]86-sequent-bsd*
34 Tsqware Sparclet sparclet-*-*
35 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
37 *** Changes in GDB 6.0:
41 Support for debugging the Objective-C programming language has been
44 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
46 DWARF 2's Call Frame Information makes available compiler generated
47 information that more exactly describes the program's run-time stack.
48 By using this information, GDB is able to provide more robust stack
51 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
52 have been updated to use a new backtrace mechanism which includes
57 GDB's remote protocol has been extended to include support for hosted
58 file I/O (where the remote target uses GDB's file system). See GDB's
59 remote protocol documentation for details.
61 * All targets using the new architecture framework.
63 All of GDB's targets have been updated to use the new internal
64 architecture framework. The way is now open for future GDB releases
65 to include cross-architecture native debugging support (i386 on amd64,
68 * GNU/Linux's Thread Local Storage (TLS)
70 GDB now includes support for for the GNU/Linux implementation of
73 * GNU/Linux's Native POSIX Thread Library (NPTL)
75 GDB's thread code has been updated to work with either the new
76 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
78 * Separate debug info.
80 GDB, in conjunction with BINUTILS, now supports a mechanism for
81 automatically loading debug information from a separate file. Instead
82 of shipping full debug and non-debug versions of system libraries,
83 system integrators can now instead ship just the stripped libraries
84 and optional debug files.
86 * DWARF 2 Location Expressions
88 DWARF 2 Location Expressions allow the compiler to more completely
89 describe the location of variables (even in optimized code) to the
92 GDB now includes preliminary support for location expressions (support
93 for DW_OP_piece is still missing).
97 A number of long standing bugs that caused GDB to die while starting a
98 Java application have been fixed. GDB's Java support is now
101 * GNU/Linux support for fork, vfork, and exec.
103 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
104 commands are now implemented for GNU/Linux. They require a 2.5.x or later
107 * GDB supports logging output to a file
109 There are two new commands, "set logging" and "show logging", which can be
110 used to capture GDB's output to a file.
112 * The meaning of "detach" has changed for gdbserver
114 The "detach" command will now resume the application, as documented. To
115 disconnect from gdbserver and leave it stopped, use the new "disconnect"
118 * d10v, m68hc11 `regs' command deprecated
120 The `info registers' command has been updated so that it displays the
121 registers using a format identical to the old `regs' command.
125 A new command, "maint set profile on/off", has been added. This command can
126 be used to enable or disable profiling while running GDB, to profile a
127 session or a set of commands. In addition there is a new configure switch,
128 "--enable-profiling", which will cause GDB to be compiled with profiling
129 data, for more informative profiling results.
131 * Default MI syntax changed to "mi2".
133 The default MI (machine interface) syntax, enabled by the command line
134 option "-i=mi", has been changed to "mi2". The previous MI syntax,
135 "mi1", can be enabled by specifying the option "-i=mi1".
137 Support for the original "mi0" syntax (included in GDB 5.0) has been
140 Fix for gdb/192: removed extraneous space when displaying frame level.
141 Fix for gdb/672: update changelist is now output in mi list format.
142 Fix for gdb/702: a -var-assign that updates the value now shows up
143 in a subsequent -var-update.
145 * New native configurations.
147 FreeBSD/amd64 x86_64-*-freebsd*
149 * Multi-arched targets.
151 HP/PA HPUX11 hppa*-*-hpux*
152 Renesas M32R/D w/simulator m32r-*-elf*
154 * OBSOLETE configurations and files
156 Configurations that have been declared obsolete in this release have
157 been commented out. Unless there is activity to revive these
158 configurations, the next release of GDB will have their sources
161 Z8000 simulator z8k-zilog-none or z8ksim
162 Matsushita MN10200 w/simulator mn10200-*-*
163 H8/500 simulator h8500-hitachi-hms or h8500hms
164 HP/PA running BSD hppa*-*-bsd*
165 HP/PA running OSF/1 hppa*-*-osf*
166 HP/PA Pro target hppa*-*-pro*
167 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
168 Sequent family i[3456]86-sequent-sysv4*
169 i[3456]86-sequent-sysv*
170 i[3456]86-sequent-bsd*
171 Tsqware Sparclet sparclet-*-*
172 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
174 * REMOVED configurations and files
177 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
178 IBM AIX PS/2 i[3456]86-*-aix
179 i386 running Mach 3.0 i[3456]86-*-mach3*
180 i386 running Mach i[3456]86-*-mach*
181 i386 running OSF/1 i[3456]86-*osf1mk*
182 HP/Apollo 68k Family m68*-apollo*-sysv*,
184 m68*-hp-bsd*, m68*-hp-hpux*
185 Argonaut Risc Chip (ARC) arc-*-*
186 Mitsubishi D30V d30v-*-*
187 Fujitsu FR30 fr30-*-elf*
188 OS/9000 i[34]86-*-os9k
189 I960 with MON960 i960-*-coff
191 * MIPS $fp behavior changed
193 The convenience variable $fp, for the MIPS, now consistently returns
194 the address of the current frame's base. Previously, depending on the
195 context, $fp could refer to either $sp or the current frame's base
196 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
197 The GNU Source-Level Debugger''.
199 *** Changes in GDB 5.3:
201 * GNU/Linux shared library multi-threaded performance improved.
203 When debugging a multi-threaded application on GNU/Linux, GDB now uses
204 `/proc', in preference to `ptrace' for memory reads. This may result
205 in an improvement in the start-up time of multi-threaded, shared
206 library applications when run under GDB. One GDB user writes: ``loads
207 shared libs like mad''.
209 * ``gdbserver'' now supports multi-threaded applications on some targets
211 Support for debugging multi-threaded applications which use
212 the GNU/Linux LinuxThreads package has been added for
213 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
214 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
216 * GDB now supports C/C++ preprocessor macros.
218 GDB now expands preprocessor macro invocations in C/C++ expressions,
219 and provides various commands for showing macro definitions and how
222 The new command `macro expand EXPRESSION' expands any macro
223 invocations in expression, and shows the result.
225 The new command `show macro MACRO-NAME' shows the definition of the
226 macro named MACRO-NAME, and where it was defined.
228 Most compilers don't include information about macros in the debugging
229 information by default. In GCC 3.1, for example, you need to compile
230 your program with the options `-gdwarf-2 -g3'. If the macro
231 information is present in the executable, GDB will read it.
233 * Multi-arched targets.
235 DEC Alpha (partial) alpha*-*-*
236 DEC VAX (partial) vax-*-*
238 National Semiconductor NS32000 (partial) ns32k-*-*
239 Motorola 68000 (partial) m68k-*-*
240 Motorola MCORE mcore-*-*
244 Fujitsu FRV architecture added by Red Hat frv*-*-*
247 * New native configurations
249 Alpha NetBSD alpha*-*-netbsd*
250 SH NetBSD sh*-*-netbsdelf*
251 MIPS NetBSD mips*-*-netbsd*
252 UltraSPARC NetBSD sparc64-*-netbsd*
254 * OBSOLETE configurations and files
256 Configurations that have been declared obsolete in this release have
257 been commented out. Unless there is activity to revive these
258 configurations, the next release of GDB will have their sources
261 Mitsubishi D30V d30v-*-*
262 OS/9000 i[34]86-*-os9k
263 IBM AIX PS/2 i[3456]86-*-aix
264 Fujitsu FR30 fr30-*-elf*
265 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
266 Argonaut Risc Chip (ARC) arc-*-*
267 i386 running Mach 3.0 i[3456]86-*-mach3*
268 i386 running Mach i[3456]86-*-mach*
269 i386 running OSF/1 i[3456]86-*osf1mk*
270 HP/Apollo 68k Family m68*-apollo*-sysv*,
272 m68*-hp-bsd*, m68*-hp-hpux*
273 I960 with MON960 i960-*-coff
277 CHILL, a Pascal like language used by telecommunications companies.
279 * REMOVED configurations and files
281 AMD 29k family via UDI a29k-amd-udi, udi29k
282 A29K VxWorks a29k-*-vxworks
283 AMD 29000 embedded, using EBMON a29k-none-none
284 AMD 29000 embedded with COFF a29k-none-coff
285 AMD 29000 embedded with a.out a29k-none-aout
287 testsuite/gdb.hp/gdb.threads-hp/ directory
289 * New command "set max-user-call-depth <nnn>"
291 This command allows the user to limit the call depth of user-defined
292 commands. The default is 1024.
294 * Changes in FreeBSD/i386 native debugging.
296 Support for the "generate-core-file" has been added.
298 * New commands "dump", "append", and "restore".
300 These commands allow data to be copied from target memory
301 to a bfd-format or binary file (dump and append), and back
302 from a file into memory (restore).
304 * Improved "next/step" support on multi-processor Alpha Tru64.
306 The previous single-step mechanism could cause unpredictable problems,
307 including the random appearance of SIGSEGV or SIGTRAP signals. The use
308 of a software single-step mechanism prevents this.
310 *** Changes in GDB 5.2.1:
318 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
319 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
320 Fix, by Joel Brobecker imported from mainline.
322 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
323 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
324 Fix, by Fred Fish, imported from mainline.
326 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
327 Surprisingly enough, it works now.
328 By Michal Ludvig, imported from mainline.
330 i386 hardware watchpoint support:
331 avoid misses on second run for some targets.
332 By Pierre Muller, imported from mainline.
334 *** Changes in GDB 5.2:
336 * New command "set trust-readonly-sections on[off]".
338 This command is a hint that tells gdb that read-only sections
339 really are read-only (ie. that their contents will not change).
340 In this mode, gdb will go to the object file rather than the
341 target to read memory from read-only sections (such as ".text").
342 This can be a significant performance improvement on some
343 (notably embedded) targets.
345 * New command "generate-core-file" (or "gcore").
347 This new gdb command allows the user to drop a core file of the child
348 process state at any time. So far it's been implemented only for
349 GNU/Linux and Solaris, but should be relatively easily ported to other
350 hosts. Argument is core file name (defaults to core.<pid>).
352 * New command line option
354 GDB now accepts --pid or -p followed by a process id.
356 * Change in command line behavior -- corefiles vs. process ids.
358 There is a subtle behavior in the way in which GDB handles
359 command line arguments. The first non-flag argument is always
360 a program to debug, but the second non-flag argument may either
361 be a corefile or a process id. Previously, GDB would attempt to
362 open the second argument as a corefile, and if that failed, would
363 issue a superfluous error message and then attempt to attach it as
364 a process. Now, if the second argument begins with a non-digit,
365 it will be treated as a corefile. If it begins with a digit,
366 GDB will attempt to attach it as a process, and if no such process
367 is found, will then attempt to open it as a corefile.
369 * Changes in ARM configurations.
371 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
372 configuration is fully multi-arch.
374 * New native configurations
376 ARM NetBSD arm*-*-netbsd*
377 x86 OpenBSD i[3456]86-*-openbsd*
378 AMD x86-64 running GNU/Linux x86_64-*-linux-*
379 Sparc64 running FreeBSD sparc64-*-freebsd*
383 Sanyo XStormy16 xstormy16-elf
385 * OBSOLETE configurations and files
387 Configurations that have been declared obsolete in this release have
388 been commented out. Unless there is activity to revive these
389 configurations, the next release of GDB will have their sources
392 AMD 29k family via UDI a29k-amd-udi, udi29k
393 A29K VxWorks a29k-*-vxworks
394 AMD 29000 embedded, using EBMON a29k-none-none
395 AMD 29000 embedded with COFF a29k-none-coff
396 AMD 29000 embedded with a.out a29k-none-aout
398 testsuite/gdb.hp/gdb.threads-hp/ directory
400 * REMOVED configurations and files
402 TI TMS320C80 tic80-*-*
404 PowerPC Solaris powerpcle-*-solaris*
405 PowerPC Windows NT powerpcle-*-cygwin32
406 PowerPC Netware powerpc-*-netware*
407 Harris/CXUX m88k m88*-harris-cxux*
408 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
409 ns32k-utek-sysv* ns32k-utek-*
410 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
411 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
412 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
413 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
414 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
416 * Changes to command line processing
418 The new `--args' feature can be used to specify command-line arguments
419 for the inferior from gdb's command line.
421 * Changes to key bindings
423 There is a new `operate-and-get-next' function bound to `C-o'.
425 *** Changes in GDB 5.1.1
427 Fix compile problem on DJGPP.
429 Fix a problem with floating-point registers on the i386 being
432 Fix to stop GDB crashing on .debug_str debug info.
434 Numerous documentation fixes.
436 Numerous testsuite fixes.
438 *** Changes in GDB 5.1:
440 * New native configurations
442 Alpha FreeBSD alpha*-*-freebsd*
443 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
444 MIPS GNU/Linux mips*-*-linux*
445 MIPS SGI Irix 6.x mips*-sgi-irix6*
447 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
451 Motorola 68HC11 and 68HC12 m68hc11-elf
453 UltraSparc running GNU/Linux sparc64-*-linux*
455 * OBSOLETE configurations and files
457 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
458 Harris/CXUX m88k m88*-harris-cxux*
459 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
460 ns32k-utek-sysv* ns32k-utek-*
461 TI TMS320C80 tic80-*-*
463 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
464 PowerPC Solaris powerpcle-*-solaris*
465 PowerPC Windows NT powerpcle-*-cygwin32
466 PowerPC Netware powerpc-*-netware*
467 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
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 N/A
472 stuff.c (Program to stuff files into a specially prepared space in kdb)
473 kdb-start.c (Main loop for the standalone kernel debugger)
475 Configurations that have been declared obsolete in this release have
476 been commented out. Unless there is activity to revive these
477 configurations, the next release of GDB will have their sources
480 * REMOVED configurations and files
482 Altos 3068 m68*-altos-*
483 Convex c1-*-*, c2-*-*
485 ARM RISCix arm-*-* (as host)
489 * GDB has been converted to ISO C.
491 GDB's source code has been converted to ISO C. In particular, the
492 sources are fully protoized, and rely on standard headers being
497 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
499 * The MI enabled by default.
501 The new machine oriented interface (MI) introduced in GDB 5.0 has been
502 revised and enabled by default. Packages which use GDB as a debugging
503 engine behind a UI or another front end are encouraged to switch to
504 using the GDB/MI interface, instead of the old annotations interface
505 which is now deprecated.
507 * Support for debugging Pascal programs.
509 GDB now includes support for debugging Pascal programs. The following
510 main features are supported:
512 - Pascal-specific data types such as sets;
514 - automatic recognition of Pascal sources based on file-name
517 - Pascal-style display of data types, variables, and functions;
519 - a Pascal expression parser.
521 However, some important features are not yet supported.
523 - Pascal string operations are not supported at all;
525 - there are some problems with boolean types;
527 - Pascal type hexadecimal constants are not supported
528 because they conflict with the internal variables format;
530 - support for Pascal objects and classes is not full yet;
532 - unlike Pascal, GDB is case-sensitive for symbol names.
534 * Changes in completion.
536 Commands such as `shell', `run' and `set args', which pass arguments
537 to inferior programs, now complete on file names, similar to what
538 users expect at the shell prompt.
540 Commands which accept locations, such as `disassemble', `print',
541 `breakpoint', `until', etc. now complete on filenames as well as
542 program symbols. Thus, if you type "break foob TAB", and the source
543 files linked into the programs include `foobar.c', that file name will
544 be one of the candidates for completion. However, file names are not
545 considered for completion after you typed a colon that delimits a file
546 name from a name of a function in that file, as in "break foo.c:bar".
548 `set demangle-style' completes on available demangling styles.
550 * New platform-independent commands:
552 It is now possible to define a post-hook for a command as well as a
553 hook that runs before the command. For more details, see the
554 documentation of `hookpost' in the GDB manual.
556 * Changes in GNU/Linux native debugging.
558 Support for debugging multi-threaded programs has been completely
559 revised for all platforms except m68k and sparc. You can now debug as
560 many threads as your system allows you to have.
562 Attach/detach is supported for multi-threaded programs.
564 Support for SSE registers was added for x86. This doesn't work for
565 multi-threaded programs though.
567 * Changes in MIPS configurations.
569 Multi-arch support is enabled for all MIPS configurations.
571 GDB can now be built as native debugger on SGI Irix 6.x systems for
572 debugging n32 executables. (Debugging 64-bit executables is not yet
575 * Unified support for hardware watchpoints in all x86 configurations.
577 Most (if not all) native x86 configurations support hardware-assisted
578 breakpoints and watchpoints in a unified manner. This support
579 implements debug register sharing between watchpoints, which allows to
580 put a virtually infinite number of watchpoints on the same address,
581 and also supports watching regions up to 16 bytes with several debug
584 The new maintenance command `maintenance show-debug-regs' toggles
585 debugging print-outs in functions that insert, remove, and test
586 watchpoints and hardware breakpoints.
588 * Changes in the DJGPP native configuration.
590 New command ``info dos sysinfo'' displays assorted information about
591 the CPU, OS, memory, and DPMI server.
593 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
594 display information about segment descriptors stored in GDT, LDT, and
597 New commands ``info dos pde'' and ``info dos pte'' display entries
598 from Page Directory and Page Tables (for now works with CWSDPMI only).
599 New command ``info dos address-pte'' displays the Page Table entry for
600 a given linear address.
602 GDB can now pass command lines longer than 126 characters to the
603 program being debugged (requires an update to the libdbg.a library
604 which is part of the DJGPP development kit).
606 DWARF2 debug info is now supported.
608 It is now possible to `step' and `next' through calls to `longjmp'.
610 * Changes in documentation.
612 All GDB documentation was converted to GFDL, the GNU Free
613 Documentation License.
615 Tracepoints-related commands are now fully documented in the GDB
618 TUI, the Text-mode User Interface, is now documented in the manual.
620 Tracepoints-related commands are now fully documented in the GDB
623 The "GDB Internals" manual now has an index. It also includes
624 documentation of `ui_out' functions, GDB coding standards, x86
625 hardware watchpoints, and memory region attributes.
627 * GDB's version number moved to ``version.in''
629 The Makefile variable VERSION has been replaced by the file
630 ``version.in''. People creating GDB distributions should update the
631 contents of this file.
635 GUD support is now a standard part of the EMACS distribution.
637 *** Changes in GDB 5.0:
639 * Improved support for debugging FP programs on x86 targets
641 Unified and much-improved support for debugging floating-point
642 programs on all x86 targets. In particular, ``info float'' now
643 displays the FP registers in the same format on all x86 targets, with
644 greater level of detail.
646 * Improvements and bugfixes in hardware-assisted watchpoints
648 It is now possible to watch array elements, struct members, and
649 bitfields with hardware-assisted watchpoints. Data-read watchpoints
650 on x86 targets no longer erroneously trigger when the address is
653 * Improvements in the native DJGPP version of GDB
655 The distribution now includes all the scripts and auxiliary files
656 necessary to build the native DJGPP version on MS-DOS/MS-Windows
657 machines ``out of the box''.
659 The DJGPP version can now debug programs that use signals. It is
660 possible to catch signals that happened in the debuggee, deliver
661 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
662 would kill the program being debugged.) Programs that hook hardware
663 interrupts (keyboard, timer, etc.) can also be debugged.
665 It is now possible to debug DJGPP programs that redirect their
666 standard handles or switch them to raw (as opposed to cooked) mode, or
667 even close them. The command ``run < foo > bar'' works as expected,
668 and ``info terminal'' reports useful information about the debuggee's
669 terminal, including raw/cooked mode, redirection, etc.
671 The DJGPP version now uses termios functions for console I/O, which
672 enables debugging graphics programs. Interrupting GDB with Ctrl-C
675 DOS-style file names with drive letters are now fully supported by
678 It is now possible to debug DJGPP programs that switch their working
679 directory. It is also possible to rerun the debuggee any number of
680 times without restarting GDB; thus, you can use the same setup,
681 breakpoints, etc. for many debugging sessions.
683 * New native configurations
685 ARM GNU/Linux arm*-*-linux*
686 PowerPC GNU/Linux powerpc-*-linux*
690 Motorola MCore mcore-*-*
691 x86 VxWorks i[3456]86-*-vxworks*
692 PowerPC VxWorks powerpc-*-vxworks*
693 TI TMS320C80 tic80-*-*
695 * OBSOLETE configurations
697 Altos 3068 m68*-altos-*
698 Convex c1-*-*, c2-*-*
700 ARM RISCix arm-*-* (as host)
703 Configurations that have been declared obsolete will be commented out,
704 but the code will be left in place. If there is no activity to revive
705 these configurations before the next release of GDB, the sources will
706 be permanently REMOVED.
708 * Gould support removed
710 Support for the Gould PowerNode and NP1 has been removed.
712 * New features for SVR4
714 On SVR4 native platforms (such as Solaris), if you attach to a process
715 without first loading a symbol file, GDB will now attempt to locate and
716 load symbols from the running process's executable file.
718 * Many C++ enhancements
720 C++ support has been greatly improved. Overload resolution now works properly
721 in almost all cases. RTTI support is on the way.
723 * Remote targets can connect to a sub-program
725 A popen(3) style serial-device has been added. This device starts a
726 sub-process (such as a stand-alone simulator) and then communicates
727 with that. The sub-program to run is specified using the syntax
728 ``|<program> <args>'' vis:
730 (gdb) set remotedebug 1
731 (gdb) target extended-remote |mn10300-elf-sim program-args
733 * MIPS 64 remote protocol
735 A long standing bug in the mips64 remote protocol where by GDB
736 expected certain 32 bit registers (ex SR) to be transfered as 32
737 instead of 64 bits has been fixed.
739 The command ``set remote-mips64-transfers-32bit-regs on'' has been
740 added to provide backward compatibility with older versions of GDB.
742 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
744 The command ``set remotebinarydownload'' command has been replaced by
745 ``set remote X-packet''. Other commands in ``set remote'' family
746 include ``set remote P-packet''.
748 * Breakpoint commands accept ranges.
750 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
751 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
752 ``tracepoint passcount'' also accepts a range of tracepoints.
754 * ``apropos'' command added.
756 The ``apropos'' command searches through command names and
757 documentation strings, printing out matches, making it much easier to
758 try to find a command that does what you are looking for.
762 A new machine oriented interface (MI) has been added to GDB. This
763 interface is designed for debug environments running GDB as a separate
764 process. This is part of the long term libGDB project. See the
765 "GDB/MI" chapter of the GDB manual for further information. It can be
766 enabled by configuring with:
768 .../configure --enable-gdbmi
770 *** Changes in GDB-4.18:
772 * New native configurations
774 HP-UX 10.20 hppa*-*-hpux10.20
775 HP-UX 11.x hppa*-*-hpux11.0*
776 M68K GNU/Linux m68*-*-linux*
780 Fujitsu FR30 fr30-*-elf*
781 Intel StrongARM strongarm-*-*
782 Mitsubishi D30V d30v-*-*
784 * OBSOLETE configurations
786 Gould PowerNode, NP1 np1-*-*, pn-*-*
788 Configurations that have been declared obsolete will be commented out,
789 but the code will be left in place. If there is no activity to revive
790 these configurations before the next release of GDB, the sources will
791 be permanently REMOVED.
795 As a compatibility experiment, GDB's source files buildsym.h and
796 buildsym.c have been converted to pure standard C, no longer
797 containing any K&R compatibility code. We believe that all systems in
798 use today either come with a standard C compiler, or have a GCC port
799 available. If this is not true, please report the affected
800 configuration to bug-gdb@gnu.org immediately. See the README file for
801 information about getting a standard C compiler if you don't have one
806 GDB now uses readline 2.2.
808 * set extension-language
810 You can now control the mapping between filename extensions and source
811 languages by using the `set extension-language' command. For instance,
812 you can ask GDB to treat .c files as C++ by saying
813 set extension-language .c c++
814 The command `info extensions' lists all of the recognized extensions
815 and their associated languages.
817 * Setting processor type for PowerPC and RS/6000
819 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
820 you can use the `set processor' command to specify what variant of the
821 PowerPC family you are debugging. The command
825 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
826 following PowerPC and RS6000 variants:
828 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
829 rs6000 IBM RS6000 ("POWER") architecture, user-level view
831 403GC IBM PowerPC 403GC
832 505 Motorola PowerPC 505
833 860 Motorola PowerPC 860 or 850
834 601 Motorola PowerPC 601
835 602 Motorola PowerPC 602
836 603 Motorola/IBM PowerPC 603 or 603e
837 604 Motorola PowerPC 604 or 604e
838 750 Motorola/IBM PowerPC 750 or 750
840 At the moment, this command just tells GDB what to name the
841 special-purpose processor registers. Since almost all the affected
842 registers are inaccessible to user-level programs, this command is
843 only useful for remote debugging in its present form.
847 Thanks to a major code donation from Hewlett-Packard, GDB now has much
848 more extensive support for HP-UX. Added features include shared
849 library support, kernel threads and hardware watchpoints for 11.00,
850 support for HP's ANSI C and C++ compilers, and a compatibility mode
851 for xdb and dbx commands.
855 HP's donation includes the new concept of catchpoints, which is a
856 generalization of the old catch command. On HP-UX, it is now possible
857 to catch exec, fork, and vfork, as well as library loading.
859 This means that the existing catch command has changed; its first
860 argument now specifies the type of catch to be set up. See the
861 output of "help catch" for a list of catchpoint types.
863 * Debugging across forks
865 On HP-UX, you can choose which process to debug when a fork() happens
870 HP has donated a curses-based terminal user interface (TUI). To get
871 it, build with --enable-tui. Although this can be enabled for any
872 configuration, at present it only works for native HP debugging.
874 * GDB remote protocol additions
876 A new protocol packet 'X' that writes binary data is now available.
877 Default behavior is to try 'X', then drop back to 'M' if the stub
878 fails to respond. The settable variable `remotebinarydownload'
879 allows explicit control over the use of 'X'.
881 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
882 full 64-bit address. The command
884 set remoteaddresssize 32
886 can be used to revert to the old behaviour. For existing remote stubs
887 the change should not be noticed, as the additional address information
890 In order to assist in debugging stubs, you may use the maintenance
891 command `packet' to send any text string to the stub. For instance,
893 maint packet heythere
895 sends the packet "$heythere#<checksum>". Note that it is very easy to
896 disrupt a debugging session by sending the wrong packet at the wrong
899 The compare-sections command allows you to compare section data on the
900 target to what is in the executable file without uploading or
901 downloading, by comparing CRC checksums.
903 * Tracing can collect general expressions
905 You may now collect general expressions at tracepoints. This requires
906 further additions to the target-side stub; see tracepoint.c and
907 doc/agentexpr.texi for further details.
909 * mask-address variable for Mips
911 For Mips targets, you may control the zeroing of the upper 32 bits of
912 a 64-bit address by entering `set mask-address on'. This is mainly
913 of interest to users of embedded R4xxx and R5xxx processors.
915 * Higher serial baud rates
917 GDB's serial code now allows you to specify baud rates 57600, 115200,
918 230400, and 460800 baud. (Note that your host system may not be able
919 to achieve all of these rates.)
923 The i960 configuration now includes an initial implementation of a
924 builtin simulator, contributed by Jim Wilson.
927 *** Changes in GDB-4.17:
929 * New native configurations
931 Alpha GNU/Linux alpha*-*-linux*
932 Unixware 2.x i[3456]86-unixware2*
933 Irix 6.x mips*-sgi-irix6*
934 PowerPC GNU/Linux powerpc-*-linux*
935 PowerPC Solaris powerpcle-*-solaris*
936 Sparc GNU/Linux sparc-*-linux*
937 Motorola sysV68 R3V7.1 m68k-motorola-sysv
941 Argonaut Risc Chip (ARC) arc-*-*
942 Hitachi H8/300S h8300*-*-*
943 Matsushita MN10200 w/simulator mn10200-*-*
944 Matsushita MN10300 w/simulator mn10300-*-*
945 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
946 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
947 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
948 Mitsubishi D10V w/simulator d10v-*-*
949 Mitsubishi M32R/D w/simulator m32r-*-elf*
950 Tsqware Sparclet sparclet-*-*
951 NEC V850 w/simulator v850-*-*
953 * New debugging protocols
955 ARM with RDI protocol arm*-*-*
956 M68K with dBUG monitor m68*-*-{aout,coff,elf}
957 DDB and LSI variants of PMON protocol mips*-*-*
958 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
959 PowerPC with SDS protocol powerpc{,le}-*-eabi
960 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
964 All configurations can now understand and use the DWARF 2 debugging
965 format. The choice is automatic, if the symbol file contains DWARF 2
970 GDB now includes basic Java language support. This support is
971 only useful with Java compilers that produce native machine code.
973 * solib-absolute-prefix and solib-search-path
975 For SunOS and SVR4 shared libraries, you may now set the prefix for
976 loading absolute shared library symbol files, and the search path for
977 locating non-absolute shared library symbol files.
979 * Live range splitting
981 GDB can now effectively debug code for which GCC has performed live
982 range splitting as part of its optimization. See gdb/doc/LRS for
983 more details on the expected format of the stabs information.
987 GDB's support for the GNU Hurd, including thread debugging, has been
988 updated to work with current versions of the Hurd.
992 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
993 instruction set. ARM GDB automatically detects when Thumb
994 instructions are in use, and adjusts disassembly and backtracing
999 GDB's MIPS target configurations now handle the MIP16 16-bit
1004 GDB now includes support for overlays; if an executable has been
1005 linked such that multiple sections are based at the same address, GDB
1006 will decide which section to use for symbolic info. You can choose to
1007 control the decision manually, using overlay commands, or implement
1008 additional target-side support and use "overlay load-target" to bring
1009 in the overlay mapping. Do "help overlay" for more detail.
1013 The command "info symbol <address>" displays information about
1014 the symbol at the specified address.
1018 The standard remote protocol now includes an extension that allows
1019 asynchronous collection and display of trace data. This requires
1020 extensive support in the target-side debugging stub. Tracing mode
1021 includes a new interaction mode in GDB and new commands: see the
1022 file tracepoint.c for more details.
1026 Configurations for embedded MIPS now include a simulator contributed
1027 by Cygnus Solutions. The simulator supports the instruction sets
1028 of most MIPS variants.
1032 Sparc configurations may now include the ERC32 simulator contributed
1033 by the European Space Agency. The simulator is not built into
1034 Sparc targets by default; configure with --enable-sim to include it.
1038 For target configurations that may include multiple variants of a
1039 basic architecture (such as MIPS and SH), you may now set the
1040 architecture explicitly. "set arch" sets, "info arch" lists
1041 the possible architectures.
1043 *** Changes in GDB-4.16:
1045 * New native configurations
1047 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1048 M68K NetBSD m68k-*-netbsd*
1049 PowerPC AIX 4.x powerpc-*-aix*
1050 PowerPC MacOS powerpc-*-macos*
1051 PowerPC Windows NT powerpcle-*-cygwin32
1052 RS/6000 AIX 4.x rs6000-*-aix4*
1056 ARM with RDP protocol arm-*-*
1057 I960 with MON960 i960-*-coff
1058 MIPS VxWorks mips*-*-vxworks*
1059 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1060 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1062 Matra Sparclet sparclet-*-*
1066 The powerpc-eabi configuration now includes the PSIM simulator,
1067 contributed by Andrew Cagney, with assistance from Mike Meissner.
1068 PSIM is a very elaborate model of the PowerPC, including not only
1069 basic instruction set execution, but also details of execution unit
1070 performance and I/O hardware. See sim/ppc/README for more details.
1074 GDB now works with Solaris 2.5.
1076 * Windows 95/NT native
1078 GDB will now work as a native debugger on Windows 95 and Windows NT.
1079 To build it from source, you must use the "gnu-win32" environment,
1080 which uses a DLL to emulate enough of Unix to run the GNU tools.
1081 Further information, binaries, and sources are available at
1082 ftp.cygnus.com, under pub/gnu-win32.
1084 * dont-repeat command
1086 If a user-defined command includes the command `dont-repeat', then the
1087 command will not be repeated if the user just types return. This is
1088 useful if the command is time-consuming to run, so that accidental
1089 extra keystrokes don't run the same command many times.
1091 * Send break instead of ^C
1093 The standard remote protocol now includes an option to send a break
1094 rather than a ^C to the target in order to interrupt it. By default,
1095 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1097 * Remote protocol timeout
1099 The standard remote protocol includes a new variable `remotetimeout'
1100 that allows you to set the number of seconds before GDB gives up trying
1101 to read from the target. The default value is 2.
1103 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1105 By default GDB will automatically keep track of objects as they are
1106 loaded and unloaded by the dynamic linker. By using the command `set
1107 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1108 when shared library events occur, thus allowing you to set breakpoints
1109 in shared libraries which are explicitly loaded by the inferior.
1111 Note this feature does not work on hpux8. On hpux9 you must link
1112 /usr/lib/end.o into your program. This feature should work
1113 automatically on hpux10.
1115 * Irix 5.x hardware watchpoint support
1117 Irix 5 configurations now support the use of hardware watchpoints.
1119 * Mips protocol "SYN garbage limit"
1121 When debugging a Mips target using the `target mips' protocol, you
1122 may set the number of characters that GDB will ignore by setting
1123 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1124 every character. The default value is 1050.
1126 * Recording and replaying remote debug sessions
1128 If you set `remotelogfile' to the name of a file, gdb will write to it
1129 a recording of a remote debug session. This recording may then be
1130 replayed back to gdb using "gdbreplay". See gdbserver/README for
1131 details. This is useful when you have a problem with GDB while doing
1132 remote debugging; you can make a recording of the session and send it
1133 to someone else, who can then recreate the problem.
1135 * Speedups for remote debugging
1137 GDB includes speedups for downloading and stepping MIPS systems using
1138 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1139 and more efficient S-record downloading.
1141 * Memory use reductions and statistics collection
1143 GDB now uses less memory and reports statistics about memory usage.
1144 Try the `maint print statistics' command, for example.
1146 *** Changes in GDB-4.15:
1148 * Psymtabs for XCOFF
1150 The symbol reader for AIX GDB now uses partial symbol tables. This
1151 can greatly improve startup time, especially for large executables.
1153 * Remote targets use caching
1155 Remote targets now use a data cache to speed up communication with the
1156 remote side. The data cache could lead to incorrect results because
1157 it doesn't know about volatile variables, thus making it impossible to
1158 debug targets which use memory mapped I/O devices. `set remotecache
1159 off' turns the the data cache off.
1161 * Remote targets may have threads
1163 The standard remote protocol now includes support for multiple threads
1164 in the target system, using new protocol commands 'H' and 'T'. See
1165 gdb/remote.c for details.
1169 If GDB is configured with `--enable-netrom', then it will include
1170 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1171 acts as though it is a bank of ROM on the target board, but you can
1172 write into it over the network. GDB's support consists only of
1173 support for fast loading into the emulated ROM; to debug, you must use
1174 another protocol, such as standard remote protocol. The usual
1175 sequence is something like
1177 target nrom <netrom-hostname>
1179 target remote <netrom-hostname>:1235
1183 GDB now includes support for the Apple Macintosh, as a host only. It
1184 may be run as either an MPW tool or as a standalone application, and
1185 it can debug through the serial port. All the usual GDB commands are
1186 available, but to the target command, you must supply "serial" as the
1187 device type instead of "/dev/ttyXX". See mpw-README in the main
1188 directory for more information on how to build. The MPW configuration
1189 scripts */mpw-config.in support only a few targets, and only the
1190 mips-idt-ecoff target has been tested.
1194 GDB configuration now uses autoconf. This is not user-visible,
1195 but does simplify configuration and building.
1199 GDB now supports hpux10.
1201 *** Changes in GDB-4.14:
1203 * New native configurations
1205 x86 FreeBSD i[345]86-*-freebsd
1206 x86 NetBSD i[345]86-*-netbsd
1207 NS32k NetBSD ns32k-*-netbsd
1208 Sparc NetBSD sparc-*-netbsd
1212 A29K VxWorks a29k-*-vxworks
1213 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1214 CPU32 EST-300 emulator m68*-*-est*
1215 PowerPC ELF powerpc-*-elf
1218 * Alpha OSF/1 support for procfs
1220 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1221 possible to attach to running processes. As the mounting of the /proc
1222 filesystem is optional on the Alpha, GDB automatically determines
1223 the availability of /proc during startup. This can lead to problems
1224 if /proc is unmounted after GDB has been started.
1226 * Arguments to user-defined commands
1228 User commands may accept up to 10 arguments separated by whitespace.
1229 Arguments are accessed within the user command via $arg0..$arg9. A
1232 print $arg0 + $arg1 + $arg2
1234 To execute the command use:
1237 Defines the command "adder" which prints the sum of its three arguments.
1238 Note the arguments are text substitutions, so they may reference variables,
1239 use complex expressions, or even perform inferior function calls.
1241 * New `if' and `while' commands
1243 This makes it possible to write more sophisticated user-defined
1244 commands. Both commands take a single argument, which is the
1245 expression to evaluate, and must be followed by the commands to
1246 execute, one per line, if the expression is nonzero, the list being
1247 terminated by the word `end'. The `if' command list may include an
1248 `else' word, which causes the following commands to be executed only
1249 if the expression is zero.
1251 * Fortran source language mode
1253 GDB now includes partial support for Fortran 77. It will recognize
1254 Fortran programs and can evaluate a subset of Fortran expressions, but
1255 variables and functions may not be handled correctly. GDB will work
1256 with G77, but does not yet know much about symbols emitted by other
1259 * Better HPUX support
1261 Most debugging facilities now work on dynamic executables for HPPAs
1262 running hpux9 or later. You can attach to running dynamically linked
1263 processes, but by default the dynamic libraries will be read-only, so
1264 for instance you won't be able to put breakpoints in them. To change
1265 that behavior do the following before running the program:
1271 This will cause the libraries to be mapped private and read-write.
1272 To revert to the normal behavior, do this:
1278 You cannot set breakpoints or examine data in the library until after
1279 the library is loaded if the function/data symbols do not have
1282 GDB can now also read debug symbols produced by the HP C compiler on
1283 HPPAs (sorry, no C++, Fortran or 68k support).
1285 * Target byte order now dynamically selectable
1287 You can choose which byte order to use with a target system, via the
1288 commands "set endian big" and "set endian little", and you can see the
1289 current setting by using "show endian". You can also give the command
1290 "set endian auto", in which case GDB will use the byte order
1291 associated with the executable. Currently, only embedded MIPS
1292 configurations support dynamic selection of target byte order.
1294 * New DOS host serial code
1296 This version uses DPMI interrupts to handle buffered I/O, so you
1297 no longer need to run asynctsr when debugging boards connected to
1300 *** Changes in GDB-4.13:
1302 * New "complete" command
1304 This lists all the possible completions for the rest of the line, if it
1305 were to be given as a command itself. This is intended for use by emacs.
1307 * Trailing space optional in prompt
1309 "set prompt" no longer adds a space for you after the prompt you set. This
1310 allows you to set a prompt which ends in a space or one that does not.
1312 * Breakpoint hit counts
1314 "info break" now displays a count of the number of times the breakpoint
1315 has been hit. This is especially useful in conjunction with "ignore"; you
1316 can ignore a large number of breakpoint hits, look at the breakpoint info
1317 to see how many times the breakpoint was hit, then run again, ignoring one
1318 less than that number, and this will get you quickly to the last hit of
1321 * Ability to stop printing at NULL character
1323 "set print null-stop" will cause GDB to stop printing the characters of
1324 an array when the first NULL is encountered. This is useful when large
1325 arrays actually contain only short strings.
1327 * Shared library breakpoints
1329 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1330 breakpoints in shared libraries before the executable is run.
1332 * Hardware watchpoints
1334 There is a new hardware breakpoint for the watch command for sparclite
1335 targets. See gdb/sparclite/hw_breakpoint.note.
1337 Hardware watchpoints are also now supported under GNU/Linux.
1341 Annotations have been added. These are for use with graphical interfaces,
1342 and are still experimental. Currently only gdba.el uses these.
1344 * Improved Irix 5 support
1346 GDB now works properly with Irix 5.2.
1348 * Improved HPPA support
1350 GDB now works properly with the latest GCC and GAS.
1352 * New native configurations
1354 Sequent PTX4 i[34]86-sequent-ptx4
1355 HPPA running OSF/1 hppa*-*-osf*
1356 Atari TT running SVR4 m68*-*-sysv4*
1357 RS/6000 LynxOS rs6000-*-lynxos*
1361 OS/9000 i[34]86-*-os9k
1362 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1365 * Hitachi SH7000 and E7000-PC ICE support
1367 There is now support for communicating with the Hitachi E7000-PC ICE.
1368 This is available automatically when GDB is configured for the SH.
1372 As usual, a variety of small fixes and improvements, both generic
1373 and configuration-specific. See the ChangeLog for more detail.
1375 *** Changes in GDB-4.12:
1377 * Irix 5 is now supported
1381 GDB-4.12 on the HPPA has a number of changes which make it unable
1382 to debug the output from the currently released versions of GCC and
1383 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1384 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1385 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1388 *** Changes in GDB-4.11:
1390 * User visible changes:
1394 The "set remotedebug" option is now consistent between the mips remote
1395 target, remote targets using the gdb-specific protocol, UDI (AMD's
1396 debug protocol for the 29k) and the 88k bug monitor. It is now an
1397 integer specifying a debug level (normally 0 or 1, but 2 means more
1398 debugging info for the mips target).
1400 * DEC Alpha native support
1402 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1403 debug info, but GDB works fairly well with the DEC compiler and should
1404 work with a future GCC release. See the README file for a few
1405 Alpha-specific notes.
1407 * Preliminary thread implementation
1409 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1411 * LynxOS native and target support for 386
1413 This release has been hosted on LynxOS 2.2, and also can be configured
1414 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1417 * Improvements in C++ mangling/demangling.
1419 This release has much better g++ debugging, specifically in name
1420 mangling/demangling, virtual function calls, print virtual table,
1421 call methods, ...etc.
1423 *** Changes in GDB-4.10:
1425 * User visible changes:
1427 Remote debugging using the GDB-specific (`target remote') protocol now
1428 supports the `load' command. This is only useful if you have some
1429 other way of getting the stub to the target system, and you can put it
1430 somewhere in memory where it won't get clobbered by the download.
1432 Filename completion now works.
1434 When run under emacs mode, the "info line" command now causes the
1435 arrow to point to the line specified. Also, "info line" prints
1436 addresses in symbolic form (as well as hex).
1438 All vxworks based targets now support a user settable option, called
1439 vxworks-timeout. This option represents the number of seconds gdb
1440 should wait for responses to rpc's. You might want to use this if
1441 your vxworks target is, perhaps, a slow software simulator or happens
1442 to be on the far side of a thin network line.
1446 This release contains support for using a DEC alpha as a GDB host for
1447 cross debugging. Native alpha debugging is not supported yet.
1450 *** Changes in GDB-4.9:
1454 This is the first GDB release which is accompanied by a matching testsuite.
1455 The testsuite requires installation of dejagnu, which should be available
1456 via ftp from most sites that carry GNU software.
1460 'Cfront' style demangling has had its name changed to 'ARM' style, to
1461 emphasize that it was written from the specifications in the C++ Annotated
1462 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1463 disclaimers, it still generated too much confusion with users attempting to
1464 use gdb with AT&T cfront.
1468 GDB now uses a standard remote interface to a simulator library.
1469 So far, the library contains simulators for the Zilog Z8001/2, the
1470 Hitachi H8/300, H8/500 and Super-H.
1472 * New targets supported
1474 H8/300 simulator h8300-hitachi-hms or h8300hms
1475 H8/500 simulator h8500-hitachi-hms or h8500hms
1476 SH simulator sh-hitachi-hms or sh
1477 Z8000 simulator z8k-zilog-none or z8ksim
1478 IDT MIPS board over serial line mips-idt-ecoff
1480 Cross-debugging to GO32 targets is supported. It requires a custom
1481 version of the i386-stub.c module which is integrated with the
1482 GO32 memory extender.
1484 * New remote protocols
1486 MIPS remote debugging protocol.
1488 * New source languages supported
1490 This version includes preliminary support for Chill, a Pascal like language
1491 used by telecommunications companies. Chill support is also being integrated
1492 into the GNU compiler, but we don't know when it will be publically available.
1495 *** Changes in GDB-4.8:
1497 * HP Precision Architecture supported
1499 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1500 version of this support was available as a set of patches from the
1501 University of Utah. GDB does not support debugging of programs
1502 compiled with the HP compiler, because HP will not document their file
1503 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1504 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1506 Many problems in the preliminary version have been fixed.
1508 * Faster and better demangling
1510 We have improved template demangling and fixed numerous bugs in the GNU style
1511 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1512 character types (wchar_t) are now supported. Demangling of each symbol is now
1513 only done once, and is cached when the symbol table for a file is read in.
1514 This results in a small increase in memory usage for C programs, a moderate
1515 increase in memory usage for C++ programs, and a fantastic speedup in
1518 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1519 from the specifications in the Annotated Reference Manual, which AT&T's
1520 compiler does not actually implement.
1522 * G++ multiple inheritance compiler problem
1524 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1525 inheritance lattices was reworked to properly discover ambiguities. We
1526 recently found an example which causes this new algorithm to fail in a
1527 very subtle way, producing bad debug information for those classes.
1528 The file 'gcc.patch' (in this directory) can be applied to gcc to
1529 circumvent the problem. A future GCC release will contain a complete
1532 The previous G++ debug info problem (mentioned below for the gdb-4.7
1533 release) is fixed in gcc version 2.3.2.
1535 * Improved configure script
1537 The `configure' script will now attempt to guess your system type if
1538 you don't supply a host system type. The old scheme of supplying a
1539 host system triplet is preferable over using this. All the magic is
1540 done in the new `config.guess' script. Examine it for details.
1542 We have also brought our configure script much more in line with the FSF's
1543 version. It now supports the --with-xxx options. In particular,
1544 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1545 The resulting GDB will not be able to read arbitrary object file formats --
1546 only the format ``expected'' to be used on the configured target system.
1547 We hope to make this the default in a future release.
1549 * Documentation improvements
1551 There's new internal documentation on how to modify GDB, and how to
1552 produce clean changes to the code. We implore people to read it
1553 before submitting changes.
1555 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1556 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1557 `info' files are also provided. To build `info' files from scratch,
1558 you will need the latest `makeinfo' release, which will be available in
1559 a future texinfo-X.Y release.
1561 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1562 We're not sure exactly which versions have this problem, but it has
1563 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1564 or better. If that isn't possible, there is a patch in
1565 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1566 around this problem.
1570 GDB now supports array constants that can be used in expressions typed in by
1571 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1572 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1575 The new directory `gdb/sparclite' contains a program that demonstrates
1576 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1578 * New native hosts supported
1580 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1581 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1583 * New targets supported
1585 AMD 29k family via UDI a29k-amd-udi or udi29k
1587 * New file formats supported
1589 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1590 HPUX core files, and SCO 3.2v2 core files.
1594 Attaching to processes now works again; thanks for the many bug reports.
1596 We have also stomped on a bunch of core dumps caused by
1597 printf_filtered("%s") problems.
1599 We eliminated a copyright problem on the rpc and ptrace header files
1600 for VxWorks, which was discovered at the last minute during the 4.7
1601 release. You should now be able to build a VxWorks GDB.
1603 You can now interrupt gdb while an attached process is running. This
1604 will cause the attached process to stop, and give control back to GDB.
1606 We fixed problems caused by using too many file descriptors
1607 for reading symbols from object files and libraries. This was
1608 especially a problem for programs that used many (~100) shared
1611 The `step' command now only enters a subroutine if there is line number
1612 information for the subroutine. Otherwise it acts like the `next'
1613 command. Previously, `step' would enter subroutines if there was
1614 any debugging information about the routine. This avoids problems
1615 when using `cc -g1' on MIPS machines.
1617 * Internal improvements
1619 GDB's internal interfaces have been improved to make it easier to support
1620 debugging of multiple languages in the future.
1622 GDB now uses a common structure for symbol information internally.
1623 Minimal symbols (derived from linkage symbols in object files), partial
1624 symbols (from a quick scan of debug information), and full symbols
1625 contain a common subset of information, making it easier to write
1626 shared code that handles any of them.
1628 * New command line options
1630 We now accept --silent as an alias for --quiet.
1634 The memory-mapped-malloc library is now licensed under the GNU Library
1635 General Public License.
1637 *** Changes in GDB-4.7:
1639 * Host/native/target split
1641 GDB has had some major internal surgery to untangle the support for
1642 hosts and remote targets. Now, when you configure GDB for a remote
1643 target, it will no longer load in all of the support for debugging
1644 local programs on the host. When fully completed and tested, this will
1645 ensure that arbitrary host/target combinations are possible.
1647 The primary conceptual shift is to separate the non-portable code in
1648 GDB into three categories. Host specific code is required any time GDB
1649 is compiled on that host, regardless of the target. Target specific
1650 code relates to the peculiarities of the target, but can be compiled on
1651 any host. Native specific code is everything else: it can only be
1652 built when the host and target are the same system. Child process
1653 handling and core file support are two common `native' examples.
1655 GDB's use of /proc for controlling Unix child processes is now cleaner.
1656 It has been split out into a single module under the `target_ops' vector,
1657 plus two native-dependent functions for each system that uses /proc.
1659 * New hosts supported
1661 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1662 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1663 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1665 * New targets supported
1667 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1668 68030 and CPU32 m68030-*-*, m68332-*-*
1670 * New native hosts supported
1672 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1673 (386bsd is not well tested yet)
1674 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1676 * New file formats supported
1678 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1679 supports reading of `a.out.adobe' object files, which are an a.out
1680 format extended with minimal information about multiple sections.
1684 `show copying' is the same as the old `info copying'.
1685 `show warranty' is the same as `info warrantee'.
1686 These were renamed for consistency. The old commands continue to work.
1688 `info handle' is a new alias for `info signals'.
1690 You can now define pre-command hooks, which attach arbitrary command
1691 scripts to any command. The commands in the hook will be executed
1692 prior to the user's command. You can also create a hook which will be
1693 executed whenever the program stops. See gdb.texinfo.
1697 We now deal with Cfront style name mangling, and can even extract type
1698 info from mangled symbols. GDB can automatically figure out which
1699 symbol mangling style your C++ compiler uses.
1701 Calling of methods and virtual functions has been improved as well.
1705 The crash that occured when debugging Sun Ansi-C compiled binaries is
1706 fixed. This was due to mishandling of the extra N_SO stabs output
1709 We also finally got Ultrix 4.2 running in house, and fixed core file
1710 support, with help from a dozen people on the net.
1712 John M. Farrell discovered that the reason that single-stepping was so
1713 slow on all of the Mips based platforms (primarily SGI and DEC) was
1714 that we were trying to demangle and lookup a symbol used for internal
1715 purposes on every instruction that was being stepped through. Changing
1716 the name of that symbol so that it couldn't be mistaken for a C++
1717 mangled symbol sped things up a great deal.
1719 Rich Pixley sped up symbol lookups in general by getting much smarter
1720 about when C++ symbol mangling is necessary. This should make symbol
1721 completion (TAB on the command line) much faster. It's not as fast as
1722 we'd like, but it's significantly faster than gdb-4.6.
1726 A new user controllable variable 'call_scratch_address' can
1727 specify the location of a scratch area to be used when GDB
1728 calls a function in the target. This is necessary because the
1729 usual method of putting the scratch area on the stack does not work
1730 in systems that have separate instruction and data spaces.
1732 We integrated changes to support the 29k UDI (Universal Debugger
1733 Interface), but discovered at the last minute that we didn't have all
1734 of the appropriate copyright paperwork. We are working with AMD to
1735 resolve this, and hope to have it available soon.
1739 We have sped up the remote serial line protocol, especially for targets
1740 with lots of registers. It now supports a new `expedited status' ('T')
1741 message which can be used in place of the existing 'S' status message.
1742 This allows the remote stub to send only the registers that GDB
1743 needs to make a quick decision about single-stepping or conditional
1744 breakpoints, eliminating the need to fetch the entire register set for
1745 each instruction being stepped through.
1747 The GDB remote serial protocol now implements a write-through cache for
1748 registers, only re-reading the registers if the target has run.
1750 There is also a new remote serial stub for SPARC processors. You can
1751 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1752 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1753 processor with a serial port.
1757 Configure.in files have become much easier to read and modify. A new
1758 `table driven' format makes it more obvious what configurations are
1759 supported, and what files each one uses.
1763 There is a new opcodes library which will eventually contain all of the
1764 disassembly routines and opcode tables. At present, it only contains
1765 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1766 disassembler (binutils/objdump) to share these routines.
1768 The libiberty library is now copylefted under the GNU Library General
1769 Public License. This allows more liberal use, and was done so libg++
1770 can use it. This makes no difference to GDB, since the Library License
1771 grants all the rights from the General Public License.
1775 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1776 reference to the stabs symbol info used by the debugger. It is (as far
1777 as we know) the only published document on this fascinating topic. We
1778 encourage you to read it, compare it to the stabs information on your
1779 system, and send improvements on the document in general (to
1780 bug-gdb@prep.ai.mit.edu).
1782 And, of course, many bugs have been fixed.
1785 *** Changes in GDB-4.6:
1787 * Better support for C++ function names
1789 GDB now accepts as input the "demangled form" of C++ overloaded function
1790 names and member function names, and can do command completion on such names
1791 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1792 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1793 Make use of command completion, it is your friend.
1795 GDB also now accepts a variety of C++ mangled symbol formats. They are
1796 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1797 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1798 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1799 for the list of formats.
1801 * G++ symbol mangling problem
1803 Recent versions of gcc have a bug in how they emit debugging information for
1804 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1805 directory) can be applied to gcc to fix the problem. Alternatively, if you
1806 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1807 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1808 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1811 * New 'maintenance' command
1813 All of the commands related to hacking GDB internals have been moved out of
1814 the main command set, and now live behind the 'maintenance' command. This
1815 can also be abbreviated as 'mt'. The following changes were made:
1817 dump-me -> maintenance dump-me
1818 info all-breakpoints -> maintenance info breakpoints
1819 printmsyms -> maintenance print msyms
1820 printobjfiles -> maintenance print objfiles
1821 printpsyms -> maintenance print psymbols
1822 printsyms -> maintenance print symbols
1824 The following commands are new:
1826 maintenance demangle Call internal GDB demangler routine to
1827 demangle a C++ link name and prints the result.
1828 maintenance print type Print a type chain for a given symbol
1830 * Change to .gdbinit file processing
1832 We now read the $HOME/.gdbinit file before processing the argv arguments
1833 (e.g. reading symbol files or core files). This allows global parameters to
1834 be set, which will apply during the symbol reading. The ./.gdbinit is still
1835 read after argv processing.
1837 * New hosts supported
1839 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1841 GNU/Linux support i386-unknown-linux or linux
1843 We are also including code to support the HP/PA running BSD and HPUX. This
1844 is almost guaranteed not to work, as we didn't have time to test or build it
1845 for this release. We are including it so that the more adventurous (or
1846 masochistic) of you can play with it. We also had major problems with the
1847 fact that the compiler that we got from HP doesn't support the -g option.
1850 * New targets supported
1852 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1854 * More smarts about finding #include files
1856 GDB now remembers the compilation directory for all include files, and for
1857 all files from which C is generated (like yacc and lex sources). This
1858 greatly improves GDB's ability to find yacc/lex sources, and include files,
1859 especially if you are debugging your program from a directory different from
1860 the one that contains your sources.
1862 We also fixed a bug which caused difficulty with listing and setting
1863 breakpoints in include files which contain C code. (In the past, you had to
1864 try twice in order to list an include file that you hadn't looked at before.)
1866 * Interesting infernals change
1868 GDB now deals with arbitrary numbers of sections, where the symbols for each
1869 section must be relocated relative to that section's landing place in the
1870 target's address space. This work was needed to support ELF with embedded
1871 stabs used by Solaris-2.0.
1873 * Bug fixes (of course!)
1875 There have been loads of fixes for the following things:
1876 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1877 i960, stabs, DOS(GO32), procfs, etc...
1879 See the ChangeLog for details.
1881 *** Changes in GDB-4.5:
1883 * New machines supported (host and target)
1885 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1887 SGI Irix-4.x mips-sgi-irix4 or iris4
1889 * New malloc package
1891 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1892 Mmalloc is capable of handling mutiple heaps of memory. It is also
1893 capable of saving a heap to a file, and then mapping it back in later.
1894 This can be used to greatly speedup the startup of GDB by using a
1895 pre-parsed symbol table which lives in a mmalloc managed heap. For
1896 more details, please read mmalloc/mmalloc.texi.
1900 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1901 'help info proc' for details.
1903 * MIPS ecoff symbol table format
1905 The code that reads MIPS symbol table format is now supported on all hosts.
1906 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1909 * File name changes for MS-DOS
1911 Many files in the config directories have been renamed to make it easier to
1912 support GDB on MS-DOSe systems (which have very restrictive file name
1913 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1914 environment) is close to working but has some remaining problems. Note
1915 that debugging of DOS programs is not supported, due to limitations
1916 in the ``operating system'', but it can be used to host cross-debugging.
1918 * Cross byte order fixes
1920 Many fixes have been made to support cross debugging of Sparc and MIPS
1921 targets from hosts whose byte order differs.
1923 * New -mapped and -readnow options
1925 If memory-mapped files are available on your system through the 'mmap'
1926 system call, you can use the -mapped option on the `file' or
1927 `symbol-file' commands to cause GDB to write the symbols from your
1928 program into a reusable file. If the program you are debugging is
1929 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1930 Future GDB debugging sessions will notice the presence of this file,
1931 and will quickly map in symbol information from it, rather than reading
1932 the symbol table from the executable program. Using the '-mapped'
1933 option in a GDB `file' or `symbol-file' command has the same effect as
1934 starting GDB with the '-mapped' command-line option.
1936 You can cause GDB to read the entire symbol table immediately by using
1937 the '-readnow' option with any of the commands that load symbol table
1938 information (or on the GDB command line). This makes the command
1939 slower, but makes future operations faster.
1941 The -mapped and -readnow options are typically combined in order to
1942 build a `fred.syms' file that contains complete symbol information.
1943 A simple GDB invocation to do nothing but build a `.syms' file for future
1946 gdb -batch -nx -mapped -readnow programname
1948 The `.syms' file is specific to the host machine on which GDB is run.
1949 It holds an exact image of GDB's internal symbol table. It cannot be
1950 shared across multiple host platforms.
1952 * longjmp() handling
1954 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1955 siglongjmp() without losing control. This feature has not yet been ported to
1956 all systems. It currently works on many 386 platforms, all MIPS-based
1957 platforms (SGI, DECstation, etc), and Sun3/4.
1961 Preliminary work has been put in to support the new Solaris OS from Sun. At
1962 this time, it can control and debug processes, but it is not capable of
1967 As always, many many bug fixes. The major areas were with g++, and mipsread.
1968 People using the MIPS-based platforms should experience fewer mysterious
1969 crashes and trashed symbol tables.
1971 *** Changes in GDB-4.4:
1973 * New machines supported (host and target)
1975 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1977 BSD Reno on Vax vax-dec-bsd
1978 Ultrix on Vax vax-dec-ultrix
1980 * New machines supported (target)
1982 AMD 29000 embedded, using EBMON a29k-none-none
1986 GDB continues to improve its handling of C++. `References' work better.
1987 The demangler has also been improved, and now deals with symbols mangled as
1988 per the Annotated C++ Reference Guide.
1990 GDB also now handles `stabs' symbol information embedded in MIPS
1991 `ecoff' symbol tables. Since the ecoff format was not easily
1992 extensible to handle new languages such as C++, this appeared to be a
1993 good way to put C++ debugging info into MIPS binaries. This option
1994 will be supported in the GNU C compiler, version 2, when it is
1997 * New features for SVR4
1999 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
2000 shared libraries. Debugging dynamically linked programs should present
2001 only minor differences from debugging statically linked programs.
2003 The `info proc' command will print out information about any process
2004 on an SVR4 system (including the one you are debugging). At the moment,
2005 it prints the address mappings of the process.
2007 If you bring up GDB on another SVR4 system, please send mail to
2008 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2010 * Better dynamic linking support in SunOS
2012 Reading symbols from shared libraries which contain debugging symbols
2013 now works properly. However, there remain issues such as automatic
2014 skipping of `transfer vector' code during function calls, which
2015 make it harder to debug code in a shared library, than to debug the
2016 same code linked statically.
2020 GDB is now using the latest `getopt' routines from the FSF. This
2021 version accepts the -- prefix for options with long names. GDB will
2022 continue to accept the old forms (-option and +option) as well.
2023 Various single letter abbreviations for options have been explicity
2024 added to the option table so that they won't get overshadowed in the
2025 future by other options that begin with the same letter.
2029 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2030 Many assorted bugs have been handled. Many more remain to be handled.
2031 See the various ChangeLog files (primarily in gdb and bfd) for details.
2034 *** Changes in GDB-4.3:
2036 * New machines supported (host and target)
2038 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2039 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2040 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2042 * Almost SCO Unix support
2044 We had hoped to support:
2045 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2046 (except for core file support), but we discovered very late in the release
2047 that it has problems with process groups that render gdb unusable. Sorry
2048 about that. I encourage people to fix it and post the fixes.
2050 * Preliminary ELF and DWARF support
2052 GDB can read ELF object files on System V Release 4, and can handle
2053 debugging records for C, in DWARF format, in ELF files. This support
2054 is preliminary. If you bring up GDB on another SVR4 system, please
2055 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2060 GDB now uses the latest `readline' library. One user-visible change
2061 is that two tabs will list possible command completions, which previously
2062 required typing M-? (meta-question mark, or ESC ?).
2066 The `stepi' bug that many of you noticed has been squashed.
2067 Many bugs in C++ have been handled. Many more remain to be handled.
2068 See the various ChangeLog files (primarily in gdb and bfd) for details.
2070 * State of the MIPS world (in case you wondered):
2072 GDB can understand the symbol tables emitted by the compilers
2073 supplied by most vendors of MIPS-based machines, including DEC. These
2074 symbol tables are in a format that essentially nobody else uses.
2076 Some versions of gcc come with an assembler post-processor called
2077 mips-tfile. This program is required if you want to do source-level
2078 debugging of gcc-compiled programs. I believe FSF does not ship
2079 mips-tfile with gcc version 1, but it will eventually come with gcc
2082 Debugging of g++ output remains a problem. g++ version 1.xx does not
2083 really support it at all. (If you're lucky, you should be able to get
2084 line numbers and stack traces to work, but no parameters or local
2085 variables.) With some work it should be possible to improve the
2088 When gcc version 2 is released, you will have somewhat better luck.
2089 However, even then you will get confusing results for inheritance and
2092 We will eventually provide full debugging of g++ output on
2093 DECstations. This will probably involve some kind of stabs-in-ecoff
2094 encapulation, but the details have not been worked out yet.
2097 *** Changes in GDB-4.2:
2099 * Improved configuration
2101 Only one copy of `configure' exists now, and it is not self-modifying.
2102 Porting BFD is simpler.
2106 The `step' and `next' commands now only stop at the first instruction
2107 of a source line. This prevents the multiple stops that used to occur
2108 in switch statements, for-loops, etc. `Step' continues to stop if a
2109 function that has debugging information is called within the line.
2113 Lots of small bugs fixed. More remain.
2115 * New host supported (not target)
2117 Intel 386 PC clone running Mach i386-none-mach
2120 *** Changes in GDB-4.1:
2122 * Multiple source language support
2124 GDB now has internal scaffolding to handle several source languages.
2125 It determines the type of each source file from its filename extension,
2126 and will switch expression parsing and number formatting to match the
2127 language of the function in the currently selected stack frame.
2128 You can also specifically set the language to be used, with
2129 `set language c' or `set language modula-2'.
2133 GDB now has preliminary support for the GNU Modula-2 compiler,
2134 currently under development at the State University of New York at
2135 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2136 continue through the fall of 1991 and into 1992.
2138 Other Modula-2 compilers are currently not supported, and attempting to
2139 debug programs compiled with them will likely result in an error as the
2140 symbol table is read. Feel free to work on it, though!
2142 There are hooks in GDB for strict type checking and range checking,
2143 in the `Modula-2 philosophy', but they do not currently work.
2147 GDB can now write to executable and core files (e.g. patch
2148 a variable's value). You must turn this switch on, specify
2149 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2150 by assigning a new value to a variable. Modifications take
2153 * Automatic SunOS shared library reading
2155 When you run your program, GDB automatically determines where its
2156 shared libraries (if any) have been loaded, and reads their symbols.
2157 The `share' command is no longer needed. This also works when
2158 examining core files.
2162 You can specify the number of lines that the `list' command shows.
2165 * New machines supported (host and target)
2167 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2168 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2169 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2171 * New hosts supported (not targets)
2173 IBM RT/PC: romp-ibm-aix or rtpc
2175 * New targets supported (not hosts)
2177 AMD 29000 embedded with COFF a29k-none-coff
2178 AMD 29000 embedded with a.out a29k-none-aout
2179 Ultracomputer remote kernel debug a29k-nyu-kern
2181 * New remote interfaces
2187 *** Changes in GDB-4.0:
2191 Wide output is wrapped at good places to make the output more readable.
2193 Gdb now supports cross-debugging from a host machine of one type to a
2194 target machine of another type. Communication with the target system
2195 is over serial lines. The ``target'' command handles connecting to the
2196 remote system; the ``load'' command will download a program into the
2197 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2198 also supports debugging of realtime processes running under VxWorks,
2199 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2200 stub on the target system.
2202 New CPUs supported include the AMD 29000 and Intel 960.
2204 GDB now reads object files and symbol tables via a ``binary file''
2205 library, which allows a single copy of GDB to debug programs of multiple
2206 object file types such as a.out and coff.
2208 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2209 refcard.dvi and refcard.ps are available to format it).
2212 * Control-Variable user interface simplified
2214 All variables that control the operation of the debugger can be set
2215 by the ``set'' command, and displayed by the ``show'' command.
2217 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2218 ``Show prompt'' produces the response:
2219 Gdb's prompt is new-gdb=>.
2221 What follows are the NEW set commands. The command ``help set'' will
2222 print a complete list of old and new set commands. ``help set FOO''
2223 will give a longer description of the variable FOO. ``show'' will show
2224 all of the variable descriptions and their current settings.
2226 confirm on/off: Enables warning questions for operations that are
2227 hard to recover from, e.g. rerunning the program while
2228 it is already running. Default is ON.
2230 editing on/off: Enables EMACS style command line editing
2231 of input. Previous lines can be recalled with
2232 control-P, the current line can be edited with control-B,
2233 you can search for commands with control-R, etc.
2236 history filename NAME: NAME is where the gdb command history
2237 will be stored. The default is .gdb_history,
2238 or the value of the environment variable
2241 history size N: The size, in commands, of the command history. The
2242 default is 256, or the value of the environment variable
2245 history save on/off: If this value is set to ON, the history file will
2246 be saved after exiting gdb. If set to OFF, the
2247 file will not be saved. The default is OFF.
2249 history expansion on/off: If this value is set to ON, then csh-like
2250 history expansion will be performed on
2251 command line input. The default is OFF.
2253 radix N: Sets the default radix for input and output. It can be set
2254 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2255 in the current radix, so "set radix 10" is always a no-op.
2257 height N: This integer value is the number of lines on a page. Default
2258 is 24, the current `stty rows'' setting, or the ``li#''
2259 setting from the termcap entry matching the environment
2262 width N: This integer value is the number of characters on a line.
2263 Default is 80, the current `stty cols'' setting, or the ``co#''
2264 setting from the termcap entry matching the environment
2267 Note: ``set screensize'' is obsolete. Use ``set height'' and
2268 ``set width'' instead.
2270 print address on/off: Print memory addresses in various command displays,
2271 such as stack traces and structure values. Gdb looks
2272 more ``symbolic'' if you turn this off; it looks more
2273 ``machine level'' with it on. Default is ON.
2275 print array on/off: Prettyprint arrays. New convenient format! Default
2278 print demangle on/off: Print C++ symbols in "source" form if on,
2281 print asm-demangle on/off: Same, for assembler level printouts
2284 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2287 * Support for Epoch Environment.
2289 The epoch environment is a version of Emacs v18 with windowing. One
2290 new command, ``inspect'', is identical to ``print'', except that if you
2291 are running in the epoch environment, the value is printed in its own
2295 * Support for Shared Libraries
2297 GDB can now debug programs and core files that use SunOS shared libraries.
2298 Symbols from a shared library cannot be referenced
2299 before the shared library has been linked with the program (this
2300 happens after you type ``run'' and before the function main() is entered).
2301 At any time after this linking (including when examining core files
2302 from dynamically linked programs), gdb reads the symbols from each
2303 shared library when you type the ``sharedlibrary'' command.
2304 It can be abbreviated ``share''.
2306 sharedlibrary REGEXP: Load shared object library symbols for files
2307 matching a unix regular expression. No argument
2308 indicates to load symbols for all shared libraries.
2310 info sharedlibrary: Status of loaded shared libraries.
2315 A watchpoint stops execution of a program whenever the value of an
2316 expression changes. Checking for this slows down execution
2317 tremendously whenever you are in the scope of the expression, but is
2318 quite useful for catching tough ``bit-spreader'' or pointer misuse
2319 problems. Some machines such as the 386 have hardware for doing this
2320 more quickly, and future versions of gdb will use this hardware.
2322 watch EXP: Set a watchpoint (breakpoint) for an expression.
2324 info watchpoints: Information about your watchpoints.
2326 delete N: Deletes watchpoint number N (same as breakpoints).
2327 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2328 enable N: Re-enables watchpoint number N (same as breakpoints).
2331 * C++ multiple inheritance
2333 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2336 * C++ exception handling
2338 Gdb now supports limited C++ exception handling. Besides the existing
2339 ability to breakpoint on an exception handler, gdb can breakpoint on
2340 the raising of an exception (before the stack is peeled back to the
2343 catch FOO: If there is a FOO exception handler in the dynamic scope,
2344 set a breakpoint to catch exceptions which may be raised there.
2345 Multiple exceptions (``catch foo bar baz'') may be caught.
2347 info catch: Lists all exceptions which may be caught in the
2348 current stack frame.
2351 * Minor command changes
2353 The command ``call func (arg, arg, ...)'' now acts like the print
2354 command, except it does not print or save a value if the function's result
2355 is void. This is similar to dbx usage.
2357 The ``up'' and ``down'' commands now always print the frame they end up
2358 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2359 frames without printing.
2361 * New directory command
2363 'dir' now adds directories to the FRONT of the source search path.
2364 The path starts off empty. Source files that contain debug information
2365 about the directory in which they were compiled can be found even
2366 with an empty path; Sun CC and GCC include this information. If GDB can't
2367 find your source file in the current directory, type "dir .".
2369 * Configuring GDB for compilation
2371 For normal use, type ``./configure host''. See README or gdb.texinfo
2374 GDB now handles cross debugging. If you are remotely debugging between
2375 two different machines, type ``./configure host -target=targ''.
2376 Host is the machine where GDB will run; targ is the machine
2377 where the program that you are debugging will run.