1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 6.0:
6 * New debugging protocols
8 M32R with SDI protocol m32r-*-elf*
10 * "set prompt-escape-char" command deleted.
12 The command "set prompt-escape-char" has been deleted. This command,
13 and its very obscure effet on GDB's prompt, was never documented,
14 tested, nor mentioned in the NEWS file.
16 * REMOVED configurations and files
18 SGI Irix-4.x mips-sgi-irix4 or iris4
19 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
20 Z8000 simulator z8k-zilog-none or z8ksim
21 Matsushita MN10200 w/simulator mn10200-*-*
22 H8/500 simulator h8500-hitachi-hms or h8500hms
23 HP/PA running BSD hppa*-*-bsd*
24 HP/PA running OSF/1 hppa*-*-osf*
25 HP/PA Pro target hppa*-*-pro*
26 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
27 Sequent family i[3456]86-sequent-sysv4*
28 i[3456]86-sequent-sysv*
29 i[3456]86-sequent-bsd*
30 Tsqware Sparclet sparclet-*-*
31 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
33 *** Changes in GDB 6.0:
37 Support for debugging the Objective-C programming language has been
40 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
42 DWARF 2's Call Frame Information makes available compiler generated
43 information that more exactly describes the program's run-time stack.
44 By using this information, GDB is able to provide more robust stack
47 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
48 have been updated to use a new backtrace mechanism which includes
53 GDB's remote protocol has been extended to include support for hosted
54 file I/O (where the remote target uses GDB's file system). See GDB's
55 remote protocol documentation for details.
57 * All targets using the new architecture framework.
59 All of GDB's targets have been updated to use the new internal
60 architecture framework. The way is now open for future GDB releases
61 to include cross-architecture native debugging support (i386 on amd64,
64 * GNU/Linux's Thread Local Storage (TLS)
66 GDB now includes support for for the GNU/Linux implementation of
69 * GNU/Linux's Native POSIX Thread Library (NPTL)
71 GDB's thread code has been updated to work with either the new
72 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
74 * Separate debug info.
76 GDB, in conjunction with BINUTILS, now supports a mechanism for
77 automatically loading debug information from a separate file. Instead
78 of shipping full debug and non-debug versions of system libraries,
79 system integrators can now instead ship just the stripped libraries
80 and optional debug files.
82 * DWARF 2 Location Expressions
84 DWARF 2 Location Expressions allow the compiler to more completely
85 describe the location of variables (even in optimized code) to the
88 GDB now includes preliminary support for location expressions (support
89 for DW_OP_piece is still missing).
93 A number of long standing bugs that caused GDB to die while starting a
94 Java application have been fixed. GDB's Java support is now
97 * GNU/Linux support for fork, vfork, and exec.
99 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
100 commands are now implemented for GNU/Linux. They require a 2.5.x or later
103 * GDB supports logging output to a file
105 There are two new commands, "set logging" and "show logging", which can be
106 used to capture GDB's output to a file.
108 * The meaning of "detach" has changed for gdbserver
110 The "detach" command will now resume the application, as documented. To
111 disconnect from gdbserver and leave it stopped, use the new "disconnect"
114 * d10v, m68hc11 `regs' command deprecated
116 The `info registers' command has been updated so that it displays the
117 registers using a format identical to the old `regs' command.
121 A new command, "maint set profile on/off", has been added. This command can
122 be used to enable or disable profiling while running GDB, to profile a
123 session or a set of commands. In addition there is a new configure switch,
124 "--enable-profiling", which will cause GDB to be compiled with profiling
125 data, for more informative profiling results.
127 * Default MI syntax changed to "mi2".
129 The default MI (machine interface) syntax, enabled by the command line
130 option "-i=mi", has been changed to "mi2". The previous MI syntax,
131 "mi1", can be enabled by specifying the option "-i=mi1".
133 Support for the original "mi0" syntax (included in GDB 5.0) has been
136 Fix for gdb/192: removed extraneous space when displaying frame level.
137 Fix for gdb/672: update changelist is now output in mi list format.
138 Fix for gdb/702: a -var-assign that updates the value now shows up
139 in a subsequent -var-update.
141 * New native configurations.
143 FreeBSD/amd64 x86_64-*-freebsd*
145 * Multi-arched targets.
147 HP/PA HPUX11 hppa*-*-hpux*
148 Renesas M32R/D w/simulator m32r-*-elf*
150 * OBSOLETE configurations and files
152 Configurations that have been declared obsolete in this release have
153 been commented out. Unless there is activity to revive these
154 configurations, the next release of GDB will have their sources
157 Z8000 simulator z8k-zilog-none or z8ksim
158 Matsushita MN10200 w/simulator mn10200-*-*
159 H8/500 simulator h8500-hitachi-hms or h8500hms
160 HP/PA running BSD hppa*-*-bsd*
161 HP/PA running OSF/1 hppa*-*-osf*
162 HP/PA Pro target hppa*-*-pro*
163 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
164 Sequent family i[3456]86-sequent-sysv4*
165 i[3456]86-sequent-sysv*
166 i[3456]86-sequent-bsd*
167 Tsqware Sparclet sparclet-*-*
168 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
170 * REMOVED configurations and files
173 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
174 IBM AIX PS/2 i[3456]86-*-aix
175 i386 running Mach 3.0 i[3456]86-*-mach3*
176 i386 running Mach i[3456]86-*-mach*
177 i386 running OSF/1 i[3456]86-*osf1mk*
178 HP/Apollo 68k Family m68*-apollo*-sysv*,
180 m68*-hp-bsd*, m68*-hp-hpux*
181 Argonaut Risc Chip (ARC) arc-*-*
182 Mitsubishi D30V d30v-*-*
183 Fujitsu FR30 fr30-*-elf*
184 OS/9000 i[34]86-*-os9k
185 I960 with MON960 i960-*-coff
187 * MIPS $fp behavior changed
189 The convenience variable $fp, for the MIPS, now consistently returns
190 the address of the current frame's base. Previously, depending on the
191 context, $fp could refer to either $sp or the current frame's base
192 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
193 The GNU Source-Level Debugger''.
195 *** Changes in GDB 5.3:
197 * GNU/Linux shared library multi-threaded performance improved.
199 When debugging a multi-threaded application on GNU/Linux, GDB now uses
200 `/proc', in preference to `ptrace' for memory reads. This may result
201 in an improvement in the start-up time of multi-threaded, shared
202 library applications when run under GDB. One GDB user writes: ``loads
203 shared libs like mad''.
205 * ``gdbserver'' now supports multi-threaded applications on some targets
207 Support for debugging multi-threaded applications which use
208 the GNU/Linux LinuxThreads package has been added for
209 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
210 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
212 * GDB now supports C/C++ preprocessor macros.
214 GDB now expands preprocessor macro invocations in C/C++ expressions,
215 and provides various commands for showing macro definitions and how
218 The new command `macro expand EXPRESSION' expands any macro
219 invocations in expression, and shows the result.
221 The new command `show macro MACRO-NAME' shows the definition of the
222 macro named MACRO-NAME, and where it was defined.
224 Most compilers don't include information about macros in the debugging
225 information by default. In GCC 3.1, for example, you need to compile
226 your program with the options `-gdwarf-2 -g3'. If the macro
227 information is present in the executable, GDB will read it.
229 * Multi-arched targets.
231 DEC Alpha (partial) alpha*-*-*
232 DEC VAX (partial) vax-*-*
234 National Semiconductor NS32000 (partial) ns32k-*-*
235 Motorola 68000 (partial) m68k-*-*
236 Motorola MCORE mcore-*-*
240 Fujitsu FRV architecture added by Red Hat frv*-*-*
243 * New native configurations
245 Alpha NetBSD alpha*-*-netbsd*
246 SH NetBSD sh*-*-netbsdelf*
247 MIPS NetBSD mips*-*-netbsd*
248 UltraSPARC NetBSD sparc64-*-netbsd*
250 * OBSOLETE configurations and files
252 Configurations that have been declared obsolete in this release have
253 been commented out. Unless there is activity to revive these
254 configurations, the next release of GDB will have their sources
257 Mitsubishi D30V d30v-*-*
258 OS/9000 i[34]86-*-os9k
259 IBM AIX PS/2 i[3456]86-*-aix
260 Fujitsu FR30 fr30-*-elf*
261 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
262 Argonaut Risc Chip (ARC) arc-*-*
263 i386 running Mach 3.0 i[3456]86-*-mach3*
264 i386 running Mach i[3456]86-*-mach*
265 i386 running OSF/1 i[3456]86-*osf1mk*
266 HP/Apollo 68k Family m68*-apollo*-sysv*,
268 m68*-hp-bsd*, m68*-hp-hpux*
269 I960 with MON960 i960-*-coff
273 CHILL, a Pascal like language used by telecommunications companies.
275 * REMOVED configurations and files
277 AMD 29k family via UDI a29k-amd-udi, udi29k
278 A29K VxWorks a29k-*-vxworks
279 AMD 29000 embedded, using EBMON a29k-none-none
280 AMD 29000 embedded with COFF a29k-none-coff
281 AMD 29000 embedded with a.out a29k-none-aout
283 testsuite/gdb.hp/gdb.threads-hp/ directory
285 * New command "set max-user-call-depth <nnn>"
287 This command allows the user to limit the call depth of user-defined
288 commands. The default is 1024.
290 * Changes in FreeBSD/i386 native debugging.
292 Support for the "generate-core-file" has been added.
294 * New commands "dump", "append", and "restore".
296 These commands allow data to be copied from target memory
297 to a bfd-format or binary file (dump and append), and back
298 from a file into memory (restore).
300 * Improved "next/step" support on multi-processor Alpha Tru64.
302 The previous single-step mechanism could cause unpredictable problems,
303 including the random appearance of SIGSEGV or SIGTRAP signals. The use
304 of a software single-step mechanism prevents this.
306 *** Changes in GDB 5.2.1:
314 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
315 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
316 Fix, by Joel Brobecker imported from mainline.
318 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
319 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
320 Fix, by Fred Fish, imported from mainline.
322 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
323 Surprisingly enough, it works now.
324 By Michal Ludvig, imported from mainline.
326 i386 hardware watchpoint support:
327 avoid misses on second run for some targets.
328 By Pierre Muller, imported from mainline.
330 *** Changes in GDB 5.2:
332 * New command "set trust-readonly-sections on[off]".
334 This command is a hint that tells gdb that read-only sections
335 really are read-only (ie. that their contents will not change).
336 In this mode, gdb will go to the object file rather than the
337 target to read memory from read-only sections (such as ".text").
338 This can be a significant performance improvement on some
339 (notably embedded) targets.
341 * New command "generate-core-file" (or "gcore").
343 This new gdb command allows the user to drop a core file of the child
344 process state at any time. So far it's been implemented only for
345 GNU/Linux and Solaris, but should be relatively easily ported to other
346 hosts. Argument is core file name (defaults to core.<pid>).
348 * New command line option
350 GDB now accepts --pid or -p followed by a process id.
352 * Change in command line behavior -- corefiles vs. process ids.
354 There is a subtle behavior in the way in which GDB handles
355 command line arguments. The first non-flag argument is always
356 a program to debug, but the second non-flag argument may either
357 be a corefile or a process id. Previously, GDB would attempt to
358 open the second argument as a corefile, and if that failed, would
359 issue a superfluous error message and then attempt to attach it as
360 a process. Now, if the second argument begins with a non-digit,
361 it will be treated as a corefile. If it begins with a digit,
362 GDB will attempt to attach it as a process, and if no such process
363 is found, will then attempt to open it as a corefile.
365 * Changes in ARM configurations.
367 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
368 configuration is fully multi-arch.
370 * New native configurations
372 ARM NetBSD arm*-*-netbsd*
373 x86 OpenBSD i[3456]86-*-openbsd*
374 AMD x86-64 running GNU/Linux x86_64-*-linux-*
375 Sparc64 running FreeBSD sparc64-*-freebsd*
379 Sanyo XStormy16 xstormy16-elf
381 * OBSOLETE configurations and files
383 Configurations that have been declared obsolete in this release have
384 been commented out. Unless there is activity to revive these
385 configurations, the next release of GDB will have their sources
388 AMD 29k family via UDI a29k-amd-udi, udi29k
389 A29K VxWorks a29k-*-vxworks
390 AMD 29000 embedded, using EBMON a29k-none-none
391 AMD 29000 embedded with COFF a29k-none-coff
392 AMD 29000 embedded with a.out a29k-none-aout
394 testsuite/gdb.hp/gdb.threads-hp/ directory
396 * REMOVED configurations and files
398 TI TMS320C80 tic80-*-*
400 PowerPC Solaris powerpcle-*-solaris*
401 PowerPC Windows NT powerpcle-*-cygwin32
402 PowerPC Netware powerpc-*-netware*
403 Harris/CXUX m88k m88*-harris-cxux*
404 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
405 ns32k-utek-sysv* ns32k-utek-*
406 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
407 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
408 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
409 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
410 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
412 * Changes to command line processing
414 The new `--args' feature can be used to specify command-line arguments
415 for the inferior from gdb's command line.
417 * Changes to key bindings
419 There is a new `operate-and-get-next' function bound to `C-o'.
421 *** Changes in GDB 5.1.1
423 Fix compile problem on DJGPP.
425 Fix a problem with floating-point registers on the i386 being
428 Fix to stop GDB crashing on .debug_str debug info.
430 Numerous documentation fixes.
432 Numerous testsuite fixes.
434 *** Changes in GDB 5.1:
436 * New native configurations
438 Alpha FreeBSD alpha*-*-freebsd*
439 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
440 MIPS GNU/Linux mips*-*-linux*
441 MIPS SGI Irix 6.x mips*-sgi-irix6*
443 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
447 Motorola 68HC11 and 68HC12 m68hc11-elf
449 UltraSparc running GNU/Linux sparc64-*-linux*
451 * OBSOLETE configurations and files
453 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
454 Harris/CXUX m88k m88*-harris-cxux*
455 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
456 ns32k-utek-sysv* ns32k-utek-*
457 TI TMS320C80 tic80-*-*
459 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
460 PowerPC Solaris powerpcle-*-solaris*
461 PowerPC Windows NT powerpcle-*-cygwin32
462 PowerPC Netware powerpc-*-netware*
463 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
464 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
465 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
466 Apple Macintosh (MPW) host N/A
468 stuff.c (Program to stuff files into a specially prepared space in kdb)
469 kdb-start.c (Main loop for the standalone kernel debugger)
471 Configurations that have been declared obsolete in this release have
472 been commented out. Unless there is activity to revive these
473 configurations, the next release of GDB will have their sources
476 * REMOVED configurations and files
478 Altos 3068 m68*-altos-*
479 Convex c1-*-*, c2-*-*
481 ARM RISCix arm-*-* (as host)
485 * GDB has been converted to ISO C.
487 GDB's source code has been converted to ISO C. In particular, the
488 sources are fully protoized, and rely on standard headers being
493 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
495 * The MI enabled by default.
497 The new machine oriented interface (MI) introduced in GDB 5.0 has been
498 revised and enabled by default. Packages which use GDB as a debugging
499 engine behind a UI or another front end are encouraged to switch to
500 using the GDB/MI interface, instead of the old annotations interface
501 which is now deprecated.
503 * Support for debugging Pascal programs.
505 GDB now includes support for debugging Pascal programs. The following
506 main features are supported:
508 - Pascal-specific data types such as sets;
510 - automatic recognition of Pascal sources based on file-name
513 - Pascal-style display of data types, variables, and functions;
515 - a Pascal expression parser.
517 However, some important features are not yet supported.
519 - Pascal string operations are not supported at all;
521 - there are some problems with boolean types;
523 - Pascal type hexadecimal constants are not supported
524 because they conflict with the internal variables format;
526 - support for Pascal objects and classes is not full yet;
528 - unlike Pascal, GDB is case-sensitive for symbol names.
530 * Changes in completion.
532 Commands such as `shell', `run' and `set args', which pass arguments
533 to inferior programs, now complete on file names, similar to what
534 users expect at the shell prompt.
536 Commands which accept locations, such as `disassemble', `print',
537 `breakpoint', `until', etc. now complete on filenames as well as
538 program symbols. Thus, if you type "break foob TAB", and the source
539 files linked into the programs include `foobar.c', that file name will
540 be one of the candidates for completion. However, file names are not
541 considered for completion after you typed a colon that delimits a file
542 name from a name of a function in that file, as in "break foo.c:bar".
544 `set demangle-style' completes on available demangling styles.
546 * New platform-independent commands:
548 It is now possible to define a post-hook for a command as well as a
549 hook that runs before the command. For more details, see the
550 documentation of `hookpost' in the GDB manual.
552 * Changes in GNU/Linux native debugging.
554 Support for debugging multi-threaded programs has been completely
555 revised for all platforms except m68k and sparc. You can now debug as
556 many threads as your system allows you to have.
558 Attach/detach is supported for multi-threaded programs.
560 Support for SSE registers was added for x86. This doesn't work for
561 multi-threaded programs though.
563 * Changes in MIPS configurations.
565 Multi-arch support is enabled for all MIPS configurations.
567 GDB can now be built as native debugger on SGI Irix 6.x systems for
568 debugging n32 executables. (Debugging 64-bit executables is not yet
571 * Unified support for hardware watchpoints in all x86 configurations.
573 Most (if not all) native x86 configurations support hardware-assisted
574 breakpoints and watchpoints in a unified manner. This support
575 implements debug register sharing between watchpoints, which allows to
576 put a virtually infinite number of watchpoints on the same address,
577 and also supports watching regions up to 16 bytes with several debug
580 The new maintenance command `maintenance show-debug-regs' toggles
581 debugging print-outs in functions that insert, remove, and test
582 watchpoints and hardware breakpoints.
584 * Changes in the DJGPP native configuration.
586 New command ``info dos sysinfo'' displays assorted information about
587 the CPU, OS, memory, and DPMI server.
589 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
590 display information about segment descriptors stored in GDT, LDT, and
593 New commands ``info dos pde'' and ``info dos pte'' display entries
594 from Page Directory and Page Tables (for now works with CWSDPMI only).
595 New command ``info dos address-pte'' displays the Page Table entry for
596 a given linear address.
598 GDB can now pass command lines longer than 126 characters to the
599 program being debugged (requires an update to the libdbg.a library
600 which is part of the DJGPP development kit).
602 DWARF2 debug info is now supported.
604 It is now possible to `step' and `next' through calls to `longjmp'.
606 * Changes in documentation.
608 All GDB documentation was converted to GFDL, the GNU Free
609 Documentation License.
611 Tracepoints-related commands are now fully documented in the GDB
614 TUI, the Text-mode User Interface, is now documented in the manual.
616 Tracepoints-related commands are now fully documented in the GDB
619 The "GDB Internals" manual now has an index. It also includes
620 documentation of `ui_out' functions, GDB coding standards, x86
621 hardware watchpoints, and memory region attributes.
623 * GDB's version number moved to ``version.in''
625 The Makefile variable VERSION has been replaced by the file
626 ``version.in''. People creating GDB distributions should update the
627 contents of this file.
631 GUD support is now a standard part of the EMACS distribution.
633 *** Changes in GDB 5.0:
635 * Improved support for debugging FP programs on x86 targets
637 Unified and much-improved support for debugging floating-point
638 programs on all x86 targets. In particular, ``info float'' now
639 displays the FP registers in the same format on all x86 targets, with
640 greater level of detail.
642 * Improvements and bugfixes in hardware-assisted watchpoints
644 It is now possible to watch array elements, struct members, and
645 bitfields with hardware-assisted watchpoints. Data-read watchpoints
646 on x86 targets no longer erroneously trigger when the address is
649 * Improvements in the native DJGPP version of GDB
651 The distribution now includes all the scripts and auxiliary files
652 necessary to build the native DJGPP version on MS-DOS/MS-Windows
653 machines ``out of the box''.
655 The DJGPP version can now debug programs that use signals. It is
656 possible to catch signals that happened in the debuggee, deliver
657 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
658 would kill the program being debugged.) Programs that hook hardware
659 interrupts (keyboard, timer, etc.) can also be debugged.
661 It is now possible to debug DJGPP programs that redirect their
662 standard handles or switch them to raw (as opposed to cooked) mode, or
663 even close them. The command ``run < foo > bar'' works as expected,
664 and ``info terminal'' reports useful information about the debuggee's
665 terminal, including raw/cooked mode, redirection, etc.
667 The DJGPP version now uses termios functions for console I/O, which
668 enables debugging graphics programs. Interrupting GDB with Ctrl-C
671 DOS-style file names with drive letters are now fully supported by
674 It is now possible to debug DJGPP programs that switch their working
675 directory. It is also possible to rerun the debuggee any number of
676 times without restarting GDB; thus, you can use the same setup,
677 breakpoints, etc. for many debugging sessions.
679 * New native configurations
681 ARM GNU/Linux arm*-*-linux*
682 PowerPC GNU/Linux powerpc-*-linux*
686 Motorola MCore mcore-*-*
687 x86 VxWorks i[3456]86-*-vxworks*
688 PowerPC VxWorks powerpc-*-vxworks*
689 TI TMS320C80 tic80-*-*
691 * OBSOLETE configurations
693 Altos 3068 m68*-altos-*
694 Convex c1-*-*, c2-*-*
696 ARM RISCix arm-*-* (as host)
699 Configurations that have been declared obsolete will be commented out,
700 but the code will be left in place. If there is no activity to revive
701 these configurations before the next release of GDB, the sources will
702 be permanently REMOVED.
704 * Gould support removed
706 Support for the Gould PowerNode and NP1 has been removed.
708 * New features for SVR4
710 On SVR4 native platforms (such as Solaris), if you attach to a process
711 without first loading a symbol file, GDB will now attempt to locate and
712 load symbols from the running process's executable file.
714 * Many C++ enhancements
716 C++ support has been greatly improved. Overload resolution now works properly
717 in almost all cases. RTTI support is on the way.
719 * Remote targets can connect to a sub-program
721 A popen(3) style serial-device has been added. This device starts a
722 sub-process (such as a stand-alone simulator) and then communicates
723 with that. The sub-program to run is specified using the syntax
724 ``|<program> <args>'' vis:
726 (gdb) set remotedebug 1
727 (gdb) target extended-remote |mn10300-elf-sim program-args
729 * MIPS 64 remote protocol
731 A long standing bug in the mips64 remote protocol where by GDB
732 expected certain 32 bit registers (ex SR) to be transfered as 32
733 instead of 64 bits has been fixed.
735 The command ``set remote-mips64-transfers-32bit-regs on'' has been
736 added to provide backward compatibility with older versions of GDB.
738 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
740 The command ``set remotebinarydownload'' command has been replaced by
741 ``set remote X-packet''. Other commands in ``set remote'' family
742 include ``set remote P-packet''.
744 * Breakpoint commands accept ranges.
746 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
747 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
748 ``tracepoint passcount'' also accepts a range of tracepoints.
750 * ``apropos'' command added.
752 The ``apropos'' command searches through command names and
753 documentation strings, printing out matches, making it much easier to
754 try to find a command that does what you are looking for.
758 A new machine oriented interface (MI) has been added to GDB. This
759 interface is designed for debug environments running GDB as a separate
760 process. This is part of the long term libGDB project. See the
761 "GDB/MI" chapter of the GDB manual for further information. It can be
762 enabled by configuring with:
764 .../configure --enable-gdbmi
766 *** Changes in GDB-4.18:
768 * New native configurations
770 HP-UX 10.20 hppa*-*-hpux10.20
771 HP-UX 11.x hppa*-*-hpux11.0*
772 M68K GNU/Linux m68*-*-linux*
776 Fujitsu FR30 fr30-*-elf*
777 Intel StrongARM strongarm-*-*
778 Mitsubishi D30V d30v-*-*
780 * OBSOLETE configurations
782 Gould PowerNode, NP1 np1-*-*, pn-*-*
784 Configurations that have been declared obsolete will be commented out,
785 but the code will be left in place. If there is no activity to revive
786 these configurations before the next release of GDB, the sources will
787 be permanently REMOVED.
791 As a compatibility experiment, GDB's source files buildsym.h and
792 buildsym.c have been converted to pure standard C, no longer
793 containing any K&R compatibility code. We believe that all systems in
794 use today either come with a standard C compiler, or have a GCC port
795 available. If this is not true, please report the affected
796 configuration to bug-gdb@gnu.org immediately. See the README file for
797 information about getting a standard C compiler if you don't have one
802 GDB now uses readline 2.2.
804 * set extension-language
806 You can now control the mapping between filename extensions and source
807 languages by using the `set extension-language' command. For instance,
808 you can ask GDB to treat .c files as C++ by saying
809 set extension-language .c c++
810 The command `info extensions' lists all of the recognized extensions
811 and their associated languages.
813 * Setting processor type for PowerPC and RS/6000
815 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
816 you can use the `set processor' command to specify what variant of the
817 PowerPC family you are debugging. The command
821 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
822 following PowerPC and RS6000 variants:
824 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
825 rs6000 IBM RS6000 ("POWER") architecture, user-level view
827 403GC IBM PowerPC 403GC
828 505 Motorola PowerPC 505
829 860 Motorola PowerPC 860 or 850
830 601 Motorola PowerPC 601
831 602 Motorola PowerPC 602
832 603 Motorola/IBM PowerPC 603 or 603e
833 604 Motorola PowerPC 604 or 604e
834 750 Motorola/IBM PowerPC 750 or 750
836 At the moment, this command just tells GDB what to name the
837 special-purpose processor registers. Since almost all the affected
838 registers are inaccessible to user-level programs, this command is
839 only useful for remote debugging in its present form.
843 Thanks to a major code donation from Hewlett-Packard, GDB now has much
844 more extensive support for HP-UX. Added features include shared
845 library support, kernel threads and hardware watchpoints for 11.00,
846 support for HP's ANSI C and C++ compilers, and a compatibility mode
847 for xdb and dbx commands.
851 HP's donation includes the new concept of catchpoints, which is a
852 generalization of the old catch command. On HP-UX, it is now possible
853 to catch exec, fork, and vfork, as well as library loading.
855 This means that the existing catch command has changed; its first
856 argument now specifies the type of catch to be set up. See the
857 output of "help catch" for a list of catchpoint types.
859 * Debugging across forks
861 On HP-UX, you can choose which process to debug when a fork() happens
866 HP has donated a curses-based terminal user interface (TUI). To get
867 it, build with --enable-tui. Although this can be enabled for any
868 configuration, at present it only works for native HP debugging.
870 * GDB remote protocol additions
872 A new protocol packet 'X' that writes binary data is now available.
873 Default behavior is to try 'X', then drop back to 'M' if the stub
874 fails to respond. The settable variable `remotebinarydownload'
875 allows explicit control over the use of 'X'.
877 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
878 full 64-bit address. The command
880 set remoteaddresssize 32
882 can be used to revert to the old behaviour. For existing remote stubs
883 the change should not be noticed, as the additional address information
886 In order to assist in debugging stubs, you may use the maintenance
887 command `packet' to send any text string to the stub. For instance,
889 maint packet heythere
891 sends the packet "$heythere#<checksum>". Note that it is very easy to
892 disrupt a debugging session by sending the wrong packet at the wrong
895 The compare-sections command allows you to compare section data on the
896 target to what is in the executable file without uploading or
897 downloading, by comparing CRC checksums.
899 * Tracing can collect general expressions
901 You may now collect general expressions at tracepoints. This requires
902 further additions to the target-side stub; see tracepoint.c and
903 doc/agentexpr.texi for further details.
905 * mask-address variable for Mips
907 For Mips targets, you may control the zeroing of the upper 32 bits of
908 a 64-bit address by entering `set mask-address on'. This is mainly
909 of interest to users of embedded R4xxx and R5xxx processors.
911 * Higher serial baud rates
913 GDB's serial code now allows you to specify baud rates 57600, 115200,
914 230400, and 460800 baud. (Note that your host system may not be able
915 to achieve all of these rates.)
919 The i960 configuration now includes an initial implementation of a
920 builtin simulator, contributed by Jim Wilson.
923 *** Changes in GDB-4.17:
925 * New native configurations
927 Alpha GNU/Linux alpha*-*-linux*
928 Unixware 2.x i[3456]86-unixware2*
929 Irix 6.x mips*-sgi-irix6*
930 PowerPC GNU/Linux powerpc-*-linux*
931 PowerPC Solaris powerpcle-*-solaris*
932 Sparc GNU/Linux sparc-*-linux*
933 Motorola sysV68 R3V7.1 m68k-motorola-sysv
937 Argonaut Risc Chip (ARC) arc-*-*
938 Hitachi H8/300S h8300*-*-*
939 Matsushita MN10200 w/simulator mn10200-*-*
940 Matsushita MN10300 w/simulator mn10300-*-*
941 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
942 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
943 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
944 Mitsubishi D10V w/simulator d10v-*-*
945 Mitsubishi M32R/D w/simulator m32r-*-elf*
946 Tsqware Sparclet sparclet-*-*
947 NEC V850 w/simulator v850-*-*
949 * New debugging protocols
951 ARM with RDI protocol arm*-*-*
952 M68K with dBUG monitor m68*-*-{aout,coff,elf}
953 DDB and LSI variants of PMON protocol mips*-*-*
954 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
955 PowerPC with SDS protocol powerpc{,le}-*-eabi
956 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
960 All configurations can now understand and use the DWARF 2 debugging
961 format. The choice is automatic, if the symbol file contains DWARF 2
966 GDB now includes basic Java language support. This support is
967 only useful with Java compilers that produce native machine code.
969 * solib-absolute-prefix and solib-search-path
971 For SunOS and SVR4 shared libraries, you may now set the prefix for
972 loading absolute shared library symbol files, and the search path for
973 locating non-absolute shared library symbol files.
975 * Live range splitting
977 GDB can now effectively debug code for which GCC has performed live
978 range splitting as part of its optimization. See gdb/doc/LRS for
979 more details on the expected format of the stabs information.
983 GDB's support for the GNU Hurd, including thread debugging, has been
984 updated to work with current versions of the Hurd.
988 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
989 instruction set. ARM GDB automatically detects when Thumb
990 instructions are in use, and adjusts disassembly and backtracing
995 GDB's MIPS target configurations now handle the MIP16 16-bit
1000 GDB now includes support for overlays; if an executable has been
1001 linked such that multiple sections are based at the same address, GDB
1002 will decide which section to use for symbolic info. You can choose to
1003 control the decision manually, using overlay commands, or implement
1004 additional target-side support and use "overlay load-target" to bring
1005 in the overlay mapping. Do "help overlay" for more detail.
1009 The command "info symbol <address>" displays information about
1010 the symbol at the specified address.
1014 The standard remote protocol now includes an extension that allows
1015 asynchronous collection and display of trace data. This requires
1016 extensive support in the target-side debugging stub. Tracing mode
1017 includes a new interaction mode in GDB and new commands: see the
1018 file tracepoint.c for more details.
1022 Configurations for embedded MIPS now include a simulator contributed
1023 by Cygnus Solutions. The simulator supports the instruction sets
1024 of most MIPS variants.
1028 Sparc configurations may now include the ERC32 simulator contributed
1029 by the European Space Agency. The simulator is not built into
1030 Sparc targets by default; configure with --enable-sim to include it.
1034 For target configurations that may include multiple variants of a
1035 basic architecture (such as MIPS and SH), you may now set the
1036 architecture explicitly. "set arch" sets, "info arch" lists
1037 the possible architectures.
1039 *** Changes in GDB-4.16:
1041 * New native configurations
1043 Windows 95, x86 Windows NT i[345]86-*-cygwin32
1044 M68K NetBSD m68k-*-netbsd*
1045 PowerPC AIX 4.x powerpc-*-aix*
1046 PowerPC MacOS powerpc-*-macos*
1047 PowerPC Windows NT powerpcle-*-cygwin32
1048 RS/6000 AIX 4.x rs6000-*-aix4*
1052 ARM with RDP protocol arm-*-*
1053 I960 with MON960 i960-*-coff
1054 MIPS VxWorks mips*-*-vxworks*
1055 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
1056 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
1058 Matra Sparclet sparclet-*-*
1062 The powerpc-eabi configuration now includes the PSIM simulator,
1063 contributed by Andrew Cagney, with assistance from Mike Meissner.
1064 PSIM is a very elaborate model of the PowerPC, including not only
1065 basic instruction set execution, but also details of execution unit
1066 performance and I/O hardware. See sim/ppc/README for more details.
1070 GDB now works with Solaris 2.5.
1072 * Windows 95/NT native
1074 GDB will now work as a native debugger on Windows 95 and Windows NT.
1075 To build it from source, you must use the "gnu-win32" environment,
1076 which uses a DLL to emulate enough of Unix to run the GNU tools.
1077 Further information, binaries, and sources are available at
1078 ftp.cygnus.com, under pub/gnu-win32.
1080 * dont-repeat command
1082 If a user-defined command includes the command `dont-repeat', then the
1083 command will not be repeated if the user just types return. This is
1084 useful if the command is time-consuming to run, so that accidental
1085 extra keystrokes don't run the same command many times.
1087 * Send break instead of ^C
1089 The standard remote protocol now includes an option to send a break
1090 rather than a ^C to the target in order to interrupt it. By default,
1091 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
1093 * Remote protocol timeout
1095 The standard remote protocol includes a new variable `remotetimeout'
1096 that allows you to set the number of seconds before GDB gives up trying
1097 to read from the target. The default value is 2.
1099 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
1101 By default GDB will automatically keep track of objects as they are
1102 loaded and unloaded by the dynamic linker. By using the command `set
1103 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
1104 when shared library events occur, thus allowing you to set breakpoints
1105 in shared libraries which are explicitly loaded by the inferior.
1107 Note this feature does not work on hpux8. On hpux9 you must link
1108 /usr/lib/end.o into your program. This feature should work
1109 automatically on hpux10.
1111 * Irix 5.x hardware watchpoint support
1113 Irix 5 configurations now support the use of hardware watchpoints.
1115 * Mips protocol "SYN garbage limit"
1117 When debugging a Mips target using the `target mips' protocol, you
1118 may set the number of characters that GDB will ignore by setting
1119 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
1120 every character. The default value is 1050.
1122 * Recording and replaying remote debug sessions
1124 If you set `remotelogfile' to the name of a file, gdb will write to it
1125 a recording of a remote debug session. This recording may then be
1126 replayed back to gdb using "gdbreplay". See gdbserver/README for
1127 details. This is useful when you have a problem with GDB while doing
1128 remote debugging; you can make a recording of the session and send it
1129 to someone else, who can then recreate the problem.
1131 * Speedups for remote debugging
1133 GDB includes speedups for downloading and stepping MIPS systems using
1134 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
1135 and more efficient S-record downloading.
1137 * Memory use reductions and statistics collection
1139 GDB now uses less memory and reports statistics about memory usage.
1140 Try the `maint print statistics' command, for example.
1142 *** Changes in GDB-4.15:
1144 * Psymtabs for XCOFF
1146 The symbol reader for AIX GDB now uses partial symbol tables. This
1147 can greatly improve startup time, especially for large executables.
1149 * Remote targets use caching
1151 Remote targets now use a data cache to speed up communication with the
1152 remote side. The data cache could lead to incorrect results because
1153 it doesn't know about volatile variables, thus making it impossible to
1154 debug targets which use memory mapped I/O devices. `set remotecache
1155 off' turns the the data cache off.
1157 * Remote targets may have threads
1159 The standard remote protocol now includes support for multiple threads
1160 in the target system, using new protocol commands 'H' and 'T'. See
1161 gdb/remote.c for details.
1165 If GDB is configured with `--enable-netrom', then it will include
1166 support for the NetROM ROM emulator from XLNT Designs. The NetROM
1167 acts as though it is a bank of ROM on the target board, but you can
1168 write into it over the network. GDB's support consists only of
1169 support for fast loading into the emulated ROM; to debug, you must use
1170 another protocol, such as standard remote protocol. The usual
1171 sequence is something like
1173 target nrom <netrom-hostname>
1175 target remote <netrom-hostname>:1235
1179 GDB now includes support for the Apple Macintosh, as a host only. It
1180 may be run as either an MPW tool or as a standalone application, and
1181 it can debug through the serial port. All the usual GDB commands are
1182 available, but to the target command, you must supply "serial" as the
1183 device type instead of "/dev/ttyXX". See mpw-README in the main
1184 directory for more information on how to build. The MPW configuration
1185 scripts */mpw-config.in support only a few targets, and only the
1186 mips-idt-ecoff target has been tested.
1190 GDB configuration now uses autoconf. This is not user-visible,
1191 but does simplify configuration and building.
1195 GDB now supports hpux10.
1197 *** Changes in GDB-4.14:
1199 * New native configurations
1201 x86 FreeBSD i[345]86-*-freebsd
1202 x86 NetBSD i[345]86-*-netbsd
1203 NS32k NetBSD ns32k-*-netbsd
1204 Sparc NetBSD sparc-*-netbsd
1208 A29K VxWorks a29k-*-vxworks
1209 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
1210 CPU32 EST-300 emulator m68*-*-est*
1211 PowerPC ELF powerpc-*-elf
1214 * Alpha OSF/1 support for procfs
1216 GDB now supports procfs under OSF/1-2.x and higher, which makes it
1217 possible to attach to running processes. As the mounting of the /proc
1218 filesystem is optional on the Alpha, GDB automatically determines
1219 the availability of /proc during startup. This can lead to problems
1220 if /proc is unmounted after GDB has been started.
1222 * Arguments to user-defined commands
1224 User commands may accept up to 10 arguments separated by whitespace.
1225 Arguments are accessed within the user command via $arg0..$arg9. A
1228 print $arg0 + $arg1 + $arg2
1230 To execute the command use:
1233 Defines the command "adder" which prints the sum of its three arguments.
1234 Note the arguments are text substitutions, so they may reference variables,
1235 use complex expressions, or even perform inferior function calls.
1237 * New `if' and `while' commands
1239 This makes it possible to write more sophisticated user-defined
1240 commands. Both commands take a single argument, which is the
1241 expression to evaluate, and must be followed by the commands to
1242 execute, one per line, if the expression is nonzero, the list being
1243 terminated by the word `end'. The `if' command list may include an
1244 `else' word, which causes the following commands to be executed only
1245 if the expression is zero.
1247 * Fortran source language mode
1249 GDB now includes partial support for Fortran 77. It will recognize
1250 Fortran programs and can evaluate a subset of Fortran expressions, but
1251 variables and functions may not be handled correctly. GDB will work
1252 with G77, but does not yet know much about symbols emitted by other
1255 * Better HPUX support
1257 Most debugging facilities now work on dynamic executables for HPPAs
1258 running hpux9 or later. You can attach to running dynamically linked
1259 processes, but by default the dynamic libraries will be read-only, so
1260 for instance you won't be able to put breakpoints in them. To change
1261 that behavior do the following before running the program:
1267 This will cause the libraries to be mapped private and read-write.
1268 To revert to the normal behavior, do this:
1274 You cannot set breakpoints or examine data in the library until after
1275 the library is loaded if the function/data symbols do not have
1278 GDB can now also read debug symbols produced by the HP C compiler on
1279 HPPAs (sorry, no C++, Fortran or 68k support).
1281 * Target byte order now dynamically selectable
1283 You can choose which byte order to use with a target system, via the
1284 commands "set endian big" and "set endian little", and you can see the
1285 current setting by using "show endian". You can also give the command
1286 "set endian auto", in which case GDB will use the byte order
1287 associated with the executable. Currently, only embedded MIPS
1288 configurations support dynamic selection of target byte order.
1290 * New DOS host serial code
1292 This version uses DPMI interrupts to handle buffered I/O, so you
1293 no longer need to run asynctsr when debugging boards connected to
1296 *** Changes in GDB-4.13:
1298 * New "complete" command
1300 This lists all the possible completions for the rest of the line, if it
1301 were to be given as a command itself. This is intended for use by emacs.
1303 * Trailing space optional in prompt
1305 "set prompt" no longer adds a space for you after the prompt you set. This
1306 allows you to set a prompt which ends in a space or one that does not.
1308 * Breakpoint hit counts
1310 "info break" now displays a count of the number of times the breakpoint
1311 has been hit. This is especially useful in conjunction with "ignore"; you
1312 can ignore a large number of breakpoint hits, look at the breakpoint info
1313 to see how many times the breakpoint was hit, then run again, ignoring one
1314 less than that number, and this will get you quickly to the last hit of
1317 * Ability to stop printing at NULL character
1319 "set print null-stop" will cause GDB to stop printing the characters of
1320 an array when the first NULL is encountered. This is useful when large
1321 arrays actually contain only short strings.
1323 * Shared library breakpoints
1325 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
1326 breakpoints in shared libraries before the executable is run.
1328 * Hardware watchpoints
1330 There is a new hardware breakpoint for the watch command for sparclite
1331 targets. See gdb/sparclite/hw_breakpoint.note.
1333 Hardware watchpoints are also now supported under GNU/Linux.
1337 Annotations have been added. These are for use with graphical interfaces,
1338 and are still experimental. Currently only gdba.el uses these.
1340 * Improved Irix 5 support
1342 GDB now works properly with Irix 5.2.
1344 * Improved HPPA support
1346 GDB now works properly with the latest GCC and GAS.
1348 * New native configurations
1350 Sequent PTX4 i[34]86-sequent-ptx4
1351 HPPA running OSF/1 hppa*-*-osf*
1352 Atari TT running SVR4 m68*-*-sysv4*
1353 RS/6000 LynxOS rs6000-*-lynxos*
1357 OS/9000 i[34]86-*-os9k
1358 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
1361 * Hitachi SH7000 and E7000-PC ICE support
1363 There is now support for communicating with the Hitachi E7000-PC ICE.
1364 This is available automatically when GDB is configured for the SH.
1368 As usual, a variety of small fixes and improvements, both generic
1369 and configuration-specific. See the ChangeLog for more detail.
1371 *** Changes in GDB-4.12:
1373 * Irix 5 is now supported
1377 GDB-4.12 on the HPPA has a number of changes which make it unable
1378 to debug the output from the currently released versions of GCC and
1379 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
1380 of GCC and GAS, versions of these tools designed to work with GDB-4.12
1381 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
1384 *** Changes in GDB-4.11:
1386 * User visible changes:
1390 The "set remotedebug" option is now consistent between the mips remote
1391 target, remote targets using the gdb-specific protocol, UDI (AMD's
1392 debug protocol for the 29k) and the 88k bug monitor. It is now an
1393 integer specifying a debug level (normally 0 or 1, but 2 means more
1394 debugging info for the mips target).
1396 * DEC Alpha native support
1398 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
1399 debug info, but GDB works fairly well with the DEC compiler and should
1400 work with a future GCC release. See the README file for a few
1401 Alpha-specific notes.
1403 * Preliminary thread implementation
1405 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
1407 * LynxOS native and target support for 386
1409 This release has been hosted on LynxOS 2.2, and also can be configured
1410 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
1413 * Improvements in C++ mangling/demangling.
1415 This release has much better g++ debugging, specifically in name
1416 mangling/demangling, virtual function calls, print virtual table,
1417 call methods, ...etc.
1419 *** Changes in GDB-4.10:
1421 * User visible changes:
1423 Remote debugging using the GDB-specific (`target remote') protocol now
1424 supports the `load' command. This is only useful if you have some
1425 other way of getting the stub to the target system, and you can put it
1426 somewhere in memory where it won't get clobbered by the download.
1428 Filename completion now works.
1430 When run under emacs mode, the "info line" command now causes the
1431 arrow to point to the line specified. Also, "info line" prints
1432 addresses in symbolic form (as well as hex).
1434 All vxworks based targets now support a user settable option, called
1435 vxworks-timeout. This option represents the number of seconds gdb
1436 should wait for responses to rpc's. You might want to use this if
1437 your vxworks target is, perhaps, a slow software simulator or happens
1438 to be on the far side of a thin network line.
1442 This release contains support for using a DEC alpha as a GDB host for
1443 cross debugging. Native alpha debugging is not supported yet.
1446 *** Changes in GDB-4.9:
1450 This is the first GDB release which is accompanied by a matching testsuite.
1451 The testsuite requires installation of dejagnu, which should be available
1452 via ftp from most sites that carry GNU software.
1456 'Cfront' style demangling has had its name changed to 'ARM' style, to
1457 emphasize that it was written from the specifications in the C++ Annotated
1458 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
1459 disclaimers, it still generated too much confusion with users attempting to
1460 use gdb with AT&T cfront.
1464 GDB now uses a standard remote interface to a simulator library.
1465 So far, the library contains simulators for the Zilog Z8001/2, the
1466 Hitachi H8/300, H8/500 and Super-H.
1468 * New targets supported
1470 H8/300 simulator h8300-hitachi-hms or h8300hms
1471 H8/500 simulator h8500-hitachi-hms or h8500hms
1472 SH simulator sh-hitachi-hms or sh
1473 Z8000 simulator z8k-zilog-none or z8ksim
1474 IDT MIPS board over serial line mips-idt-ecoff
1476 Cross-debugging to GO32 targets is supported. It requires a custom
1477 version of the i386-stub.c module which is integrated with the
1478 GO32 memory extender.
1480 * New remote protocols
1482 MIPS remote debugging protocol.
1484 * New source languages supported
1486 This version includes preliminary support for Chill, a Pascal like language
1487 used by telecommunications companies. Chill support is also being integrated
1488 into the GNU compiler, but we don't know when it will be publically available.
1491 *** Changes in GDB-4.8:
1493 * HP Precision Architecture supported
1495 GDB now supports HP PA-RISC machines running HPUX. A preliminary
1496 version of this support was available as a set of patches from the
1497 University of Utah. GDB does not support debugging of programs
1498 compiled with the HP compiler, because HP will not document their file
1499 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
1500 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
1502 Many problems in the preliminary version have been fixed.
1504 * Faster and better demangling
1506 We have improved template demangling and fixed numerous bugs in the GNU style
1507 demangler. It can now handle type modifiers such as `static' or `const'. Wide
1508 character types (wchar_t) are now supported. Demangling of each symbol is now
1509 only done once, and is cached when the symbol table for a file is read in.
1510 This results in a small increase in memory usage for C programs, a moderate
1511 increase in memory usage for C++ programs, and a fantastic speedup in
1514 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
1515 from the specifications in the Annotated Reference Manual, which AT&T's
1516 compiler does not actually implement.
1518 * G++ multiple inheritance compiler problem
1520 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
1521 inheritance lattices was reworked to properly discover ambiguities. We
1522 recently found an example which causes this new algorithm to fail in a
1523 very subtle way, producing bad debug information for those classes.
1524 The file 'gcc.patch' (in this directory) can be applied to gcc to
1525 circumvent the problem. A future GCC release will contain a complete
1528 The previous G++ debug info problem (mentioned below for the gdb-4.7
1529 release) is fixed in gcc version 2.3.2.
1531 * Improved configure script
1533 The `configure' script will now attempt to guess your system type if
1534 you don't supply a host system type. The old scheme of supplying a
1535 host system triplet is preferable over using this. All the magic is
1536 done in the new `config.guess' script. Examine it for details.
1538 We have also brought our configure script much more in line with the FSF's
1539 version. It now supports the --with-xxx options. In particular,
1540 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
1541 The resulting GDB will not be able to read arbitrary object file formats --
1542 only the format ``expected'' to be used on the configured target system.
1543 We hope to make this the default in a future release.
1545 * Documentation improvements
1547 There's new internal documentation on how to modify GDB, and how to
1548 produce clean changes to the code. We implore people to read it
1549 before submitting changes.
1551 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
1552 M4 macros. The new texinfo.tex is provided in this release. Pre-built
1553 `info' files are also provided. To build `info' files from scratch,
1554 you will need the latest `makeinfo' release, which will be available in
1555 a future texinfo-X.Y release.
1557 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
1558 We're not sure exactly which versions have this problem, but it has
1559 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
1560 or better. If that isn't possible, there is a patch in
1561 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
1562 around this problem.
1566 GDB now supports array constants that can be used in expressions typed in by
1567 the user. The syntax is `{element, element, ...}'. Ie: you can now type
1568 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
1571 The new directory `gdb/sparclite' contains a program that demonstrates
1572 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
1574 * New native hosts supported
1576 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
1577 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
1579 * New targets supported
1581 AMD 29k family via UDI a29k-amd-udi or udi29k
1583 * New file formats supported
1585 BFD now supports reading HP/PA-RISC executables (SOM file format?),
1586 HPUX core files, and SCO 3.2v2 core files.
1590 Attaching to processes now works again; thanks for the many bug reports.
1592 We have also stomped on a bunch of core dumps caused by
1593 printf_filtered("%s") problems.
1595 We eliminated a copyright problem on the rpc and ptrace header files
1596 for VxWorks, which was discovered at the last minute during the 4.7
1597 release. You should now be able to build a VxWorks GDB.
1599 You can now interrupt gdb while an attached process is running. This
1600 will cause the attached process to stop, and give control back to GDB.
1602 We fixed problems caused by using too many file descriptors
1603 for reading symbols from object files and libraries. This was
1604 especially a problem for programs that used many (~100) shared
1607 The `step' command now only enters a subroutine if there is line number
1608 information for the subroutine. Otherwise it acts like the `next'
1609 command. Previously, `step' would enter subroutines if there was
1610 any debugging information about the routine. This avoids problems
1611 when using `cc -g1' on MIPS machines.
1613 * Internal improvements
1615 GDB's internal interfaces have been improved to make it easier to support
1616 debugging of multiple languages in the future.
1618 GDB now uses a common structure for symbol information internally.
1619 Minimal symbols (derived from linkage symbols in object files), partial
1620 symbols (from a quick scan of debug information), and full symbols
1621 contain a common subset of information, making it easier to write
1622 shared code that handles any of them.
1624 * New command line options
1626 We now accept --silent as an alias for --quiet.
1630 The memory-mapped-malloc library is now licensed under the GNU Library
1631 General Public License.
1633 *** Changes in GDB-4.7:
1635 * Host/native/target split
1637 GDB has had some major internal surgery to untangle the support for
1638 hosts and remote targets. Now, when you configure GDB for a remote
1639 target, it will no longer load in all of the support for debugging
1640 local programs on the host. When fully completed and tested, this will
1641 ensure that arbitrary host/target combinations are possible.
1643 The primary conceptual shift is to separate the non-portable code in
1644 GDB into three categories. Host specific code is required any time GDB
1645 is compiled on that host, regardless of the target. Target specific
1646 code relates to the peculiarities of the target, but can be compiled on
1647 any host. Native specific code is everything else: it can only be
1648 built when the host and target are the same system. Child process
1649 handling and core file support are two common `native' examples.
1651 GDB's use of /proc for controlling Unix child processes is now cleaner.
1652 It has been split out into a single module under the `target_ops' vector,
1653 plus two native-dependent functions for each system that uses /proc.
1655 * New hosts supported
1657 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1658 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1659 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1661 * New targets supported
1663 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1664 68030 and CPU32 m68030-*-*, m68332-*-*
1666 * New native hosts supported
1668 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1669 (386bsd is not well tested yet)
1670 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1672 * New file formats supported
1674 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1675 supports reading of `a.out.adobe' object files, which are an a.out
1676 format extended with minimal information about multiple sections.
1680 `show copying' is the same as the old `info copying'.
1681 `show warranty' is the same as `info warrantee'.
1682 These were renamed for consistency. The old commands continue to work.
1684 `info handle' is a new alias for `info signals'.
1686 You can now define pre-command hooks, which attach arbitrary command
1687 scripts to any command. The commands in the hook will be executed
1688 prior to the user's command. You can also create a hook which will be
1689 executed whenever the program stops. See gdb.texinfo.
1693 We now deal with Cfront style name mangling, and can even extract type
1694 info from mangled symbols. GDB can automatically figure out which
1695 symbol mangling style your C++ compiler uses.
1697 Calling of methods and virtual functions has been improved as well.
1701 The crash that occured when debugging Sun Ansi-C compiled binaries is
1702 fixed. This was due to mishandling of the extra N_SO stabs output
1705 We also finally got Ultrix 4.2 running in house, and fixed core file
1706 support, with help from a dozen people on the net.
1708 John M. Farrell discovered that the reason that single-stepping was so
1709 slow on all of the Mips based platforms (primarily SGI and DEC) was
1710 that we were trying to demangle and lookup a symbol used for internal
1711 purposes on every instruction that was being stepped through. Changing
1712 the name of that symbol so that it couldn't be mistaken for a C++
1713 mangled symbol sped things up a great deal.
1715 Rich Pixley sped up symbol lookups in general by getting much smarter
1716 about when C++ symbol mangling is necessary. This should make symbol
1717 completion (TAB on the command line) much faster. It's not as fast as
1718 we'd like, but it's significantly faster than gdb-4.6.
1722 A new user controllable variable 'call_scratch_address' can
1723 specify the location of a scratch area to be used when GDB
1724 calls a function in the target. This is necessary because the
1725 usual method of putting the scratch area on the stack does not work
1726 in systems that have separate instruction and data spaces.
1728 We integrated changes to support the 29k UDI (Universal Debugger
1729 Interface), but discovered at the last minute that we didn't have all
1730 of the appropriate copyright paperwork. We are working with AMD to
1731 resolve this, and hope to have it available soon.
1735 We have sped up the remote serial line protocol, especially for targets
1736 with lots of registers. It now supports a new `expedited status' ('T')
1737 message which can be used in place of the existing 'S' status message.
1738 This allows the remote stub to send only the registers that GDB
1739 needs to make a quick decision about single-stepping or conditional
1740 breakpoints, eliminating the need to fetch the entire register set for
1741 each instruction being stepped through.
1743 The GDB remote serial protocol now implements a write-through cache for
1744 registers, only re-reading the registers if the target has run.
1746 There is also a new remote serial stub for SPARC processors. You can
1747 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1748 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1749 processor with a serial port.
1753 Configure.in files have become much easier to read and modify. A new
1754 `table driven' format makes it more obvious what configurations are
1755 supported, and what files each one uses.
1759 There is a new opcodes library which will eventually contain all of the
1760 disassembly routines and opcode tables. At present, it only contains
1761 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1762 disassembler (binutils/objdump) to share these routines.
1764 The libiberty library is now copylefted under the GNU Library General
1765 Public License. This allows more liberal use, and was done so libg++
1766 can use it. This makes no difference to GDB, since the Library License
1767 grants all the rights from the General Public License.
1771 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1772 reference to the stabs symbol info used by the debugger. It is (as far
1773 as we know) the only published document on this fascinating topic. We
1774 encourage you to read it, compare it to the stabs information on your
1775 system, and send improvements on the document in general (to
1776 bug-gdb@prep.ai.mit.edu).
1778 And, of course, many bugs have been fixed.
1781 *** Changes in GDB-4.6:
1783 * Better support for C++ function names
1785 GDB now accepts as input the "demangled form" of C++ overloaded function
1786 names and member function names, and can do command completion on such names
1787 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1788 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1789 Make use of command completion, it is your friend.
1791 GDB also now accepts a variety of C++ mangled symbol formats. They are
1792 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1793 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1794 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1795 for the list of formats.
1797 * G++ symbol mangling problem
1799 Recent versions of gcc have a bug in how they emit debugging information for
1800 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1801 directory) can be applied to gcc to fix the problem. Alternatively, if you
1802 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1803 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1804 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1807 * New 'maintenance' command
1809 All of the commands related to hacking GDB internals have been moved out of
1810 the main command set, and now live behind the 'maintenance' command. This
1811 can also be abbreviated as 'mt'. The following changes were made:
1813 dump-me -> maintenance dump-me
1814 info all-breakpoints -> maintenance info breakpoints
1815 printmsyms -> maintenance print msyms
1816 printobjfiles -> maintenance print objfiles
1817 printpsyms -> maintenance print psymbols
1818 printsyms -> maintenance print symbols
1820 The following commands are new:
1822 maintenance demangle Call internal GDB demangler routine to
1823 demangle a C++ link name and prints the result.
1824 maintenance print type Print a type chain for a given symbol
1826 * Change to .gdbinit file processing
1828 We now read the $HOME/.gdbinit file before processing the argv arguments
1829 (e.g. reading symbol files or core files). This allows global parameters to
1830 be set, which will apply during the symbol reading. The ./.gdbinit is still
1831 read after argv processing.
1833 * New hosts supported
1835 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1837 GNU/Linux support i386-unknown-linux or linux
1839 We are also including code to support the HP/PA running BSD and HPUX. This
1840 is almost guaranteed not to work, as we didn't have time to test or build it
1841 for this release. We are including it so that the more adventurous (or
1842 masochistic) of you can play with it. We also had major problems with the
1843 fact that the compiler that we got from HP doesn't support the -g option.
1846 * New targets supported
1848 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1850 * More smarts about finding #include files
1852 GDB now remembers the compilation directory for all include files, and for
1853 all files from which C is generated (like yacc and lex sources). This
1854 greatly improves GDB's ability to find yacc/lex sources, and include files,
1855 especially if you are debugging your program from a directory different from
1856 the one that contains your sources.
1858 We also fixed a bug which caused difficulty with listing and setting
1859 breakpoints in include files which contain C code. (In the past, you had to
1860 try twice in order to list an include file that you hadn't looked at before.)
1862 * Interesting infernals change
1864 GDB now deals with arbitrary numbers of sections, where the symbols for each
1865 section must be relocated relative to that section's landing place in the
1866 target's address space. This work was needed to support ELF with embedded
1867 stabs used by Solaris-2.0.
1869 * Bug fixes (of course!)
1871 There have been loads of fixes for the following things:
1872 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1873 i960, stabs, DOS(GO32), procfs, etc...
1875 See the ChangeLog for details.
1877 *** Changes in GDB-4.5:
1879 * New machines supported (host and target)
1881 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1883 SGI Irix-4.x mips-sgi-irix4 or iris4
1885 * New malloc package
1887 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1888 Mmalloc is capable of handling mutiple heaps of memory. It is also
1889 capable of saving a heap to a file, and then mapping it back in later.
1890 This can be used to greatly speedup the startup of GDB by using a
1891 pre-parsed symbol table which lives in a mmalloc managed heap. For
1892 more details, please read mmalloc/mmalloc.texi.
1896 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1897 'help info proc' for details.
1899 * MIPS ecoff symbol table format
1901 The code that reads MIPS symbol table format is now supported on all hosts.
1902 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1905 * File name changes for MS-DOS
1907 Many files in the config directories have been renamed to make it easier to
1908 support GDB on MS-DOSe systems (which have very restrictive file name
1909 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1910 environment) is close to working but has some remaining problems. Note
1911 that debugging of DOS programs is not supported, due to limitations
1912 in the ``operating system'', but it can be used to host cross-debugging.
1914 * Cross byte order fixes
1916 Many fixes have been made to support cross debugging of Sparc and MIPS
1917 targets from hosts whose byte order differs.
1919 * New -mapped and -readnow options
1921 If memory-mapped files are available on your system through the 'mmap'
1922 system call, you can use the -mapped option on the `file' or
1923 `symbol-file' commands to cause GDB to write the symbols from your
1924 program into a reusable file. If the program you are debugging is
1925 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1926 Future GDB debugging sessions will notice the presence of this file,
1927 and will quickly map in symbol information from it, rather than reading
1928 the symbol table from the executable program. Using the '-mapped'
1929 option in a GDB `file' or `symbol-file' command has the same effect as
1930 starting GDB with the '-mapped' command-line option.
1932 You can cause GDB to read the entire symbol table immediately by using
1933 the '-readnow' option with any of the commands that load symbol table
1934 information (or on the GDB command line). This makes the command
1935 slower, but makes future operations faster.
1937 The -mapped and -readnow options are typically combined in order to
1938 build a `fred.syms' file that contains complete symbol information.
1939 A simple GDB invocation to do nothing but build a `.syms' file for future
1942 gdb -batch -nx -mapped -readnow programname
1944 The `.syms' file is specific to the host machine on which GDB is run.
1945 It holds an exact image of GDB's internal symbol table. It cannot be
1946 shared across multiple host platforms.
1948 * longjmp() handling
1950 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1951 siglongjmp() without losing control. This feature has not yet been ported to
1952 all systems. It currently works on many 386 platforms, all MIPS-based
1953 platforms (SGI, DECstation, etc), and Sun3/4.
1957 Preliminary work has been put in to support the new Solaris OS from Sun. At
1958 this time, it can control and debug processes, but it is not capable of
1963 As always, many many bug fixes. The major areas were with g++, and mipsread.
1964 People using the MIPS-based platforms should experience fewer mysterious
1965 crashes and trashed symbol tables.
1967 *** Changes in GDB-4.4:
1969 * New machines supported (host and target)
1971 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1973 BSD Reno on Vax vax-dec-bsd
1974 Ultrix on Vax vax-dec-ultrix
1976 * New machines supported (target)
1978 AMD 29000 embedded, using EBMON a29k-none-none
1982 GDB continues to improve its handling of C++. `References' work better.
1983 The demangler has also been improved, and now deals with symbols mangled as
1984 per the Annotated C++ Reference Guide.
1986 GDB also now handles `stabs' symbol information embedded in MIPS
1987 `ecoff' symbol tables. Since the ecoff format was not easily
1988 extensible to handle new languages such as C++, this appeared to be a
1989 good way to put C++ debugging info into MIPS binaries. This option
1990 will be supported in the GNU C compiler, version 2, when it is
1993 * New features for SVR4
1995 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1996 shared libraries. Debugging dynamically linked programs should present
1997 only minor differences from debugging statically linked programs.
1999 The `info proc' command will print out information about any process
2000 on an SVR4 system (including the one you are debugging). At the moment,
2001 it prints the address mappings of the process.
2003 If you bring up GDB on another SVR4 system, please send mail to
2004 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
2006 * Better dynamic linking support in SunOS
2008 Reading symbols from shared libraries which contain debugging symbols
2009 now works properly. However, there remain issues such as automatic
2010 skipping of `transfer vector' code during function calls, which
2011 make it harder to debug code in a shared library, than to debug the
2012 same code linked statically.
2016 GDB is now using the latest `getopt' routines from the FSF. This
2017 version accepts the -- prefix for options with long names. GDB will
2018 continue to accept the old forms (-option and +option) as well.
2019 Various single letter abbreviations for options have been explicity
2020 added to the option table so that they won't get overshadowed in the
2021 future by other options that begin with the same letter.
2025 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
2026 Many assorted bugs have been handled. Many more remain to be handled.
2027 See the various ChangeLog files (primarily in gdb and bfd) for details.
2030 *** Changes in GDB-4.3:
2032 * New machines supported (host and target)
2034 Amiga 3000 running Amix m68k-cbm-svr4 or amix
2035 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
2036 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2038 * Almost SCO Unix support
2040 We had hoped to support:
2041 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
2042 (except for core file support), but we discovered very late in the release
2043 that it has problems with process groups that render gdb unusable. Sorry
2044 about that. I encourage people to fix it and post the fixes.
2046 * Preliminary ELF and DWARF support
2048 GDB can read ELF object files on System V Release 4, and can handle
2049 debugging records for C, in DWARF format, in ELF files. This support
2050 is preliminary. If you bring up GDB on another SVR4 system, please
2051 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
2056 GDB now uses the latest `readline' library. One user-visible change
2057 is that two tabs will list possible command completions, which previously
2058 required typing M-? (meta-question mark, or ESC ?).
2062 The `stepi' bug that many of you noticed has been squashed.
2063 Many bugs in C++ have been handled. Many more remain to be handled.
2064 See the various ChangeLog files (primarily in gdb and bfd) for details.
2066 * State of the MIPS world (in case you wondered):
2068 GDB can understand the symbol tables emitted by the compilers
2069 supplied by most vendors of MIPS-based machines, including DEC. These
2070 symbol tables are in a format that essentially nobody else uses.
2072 Some versions of gcc come with an assembler post-processor called
2073 mips-tfile. This program is required if you want to do source-level
2074 debugging of gcc-compiled programs. I believe FSF does not ship
2075 mips-tfile with gcc version 1, but it will eventually come with gcc
2078 Debugging of g++ output remains a problem. g++ version 1.xx does not
2079 really support it at all. (If you're lucky, you should be able to get
2080 line numbers and stack traces to work, but no parameters or local
2081 variables.) With some work it should be possible to improve the
2084 When gcc version 2 is released, you will have somewhat better luck.
2085 However, even then you will get confusing results for inheritance and
2088 We will eventually provide full debugging of g++ output on
2089 DECstations. This will probably involve some kind of stabs-in-ecoff
2090 encapulation, but the details have not been worked out yet.
2093 *** Changes in GDB-4.2:
2095 * Improved configuration
2097 Only one copy of `configure' exists now, and it is not self-modifying.
2098 Porting BFD is simpler.
2102 The `step' and `next' commands now only stop at the first instruction
2103 of a source line. This prevents the multiple stops that used to occur
2104 in switch statements, for-loops, etc. `Step' continues to stop if a
2105 function that has debugging information is called within the line.
2109 Lots of small bugs fixed. More remain.
2111 * New host supported (not target)
2113 Intel 386 PC clone running Mach i386-none-mach
2116 *** Changes in GDB-4.1:
2118 * Multiple source language support
2120 GDB now has internal scaffolding to handle several source languages.
2121 It determines the type of each source file from its filename extension,
2122 and will switch expression parsing and number formatting to match the
2123 language of the function in the currently selected stack frame.
2124 You can also specifically set the language to be used, with
2125 `set language c' or `set language modula-2'.
2129 GDB now has preliminary support for the GNU Modula-2 compiler,
2130 currently under development at the State University of New York at
2131 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
2132 continue through the fall of 1991 and into 1992.
2134 Other Modula-2 compilers are currently not supported, and attempting to
2135 debug programs compiled with them will likely result in an error as the
2136 symbol table is read. Feel free to work on it, though!
2138 There are hooks in GDB for strict type checking and range checking,
2139 in the `Modula-2 philosophy', but they do not currently work.
2143 GDB can now write to executable and core files (e.g. patch
2144 a variable's value). You must turn this switch on, specify
2145 the file ("exec foo" or "core foo"), *then* modify it, e.g.
2146 by assigning a new value to a variable. Modifications take
2149 * Automatic SunOS shared library reading
2151 When you run your program, GDB automatically determines where its
2152 shared libraries (if any) have been loaded, and reads their symbols.
2153 The `share' command is no longer needed. This also works when
2154 examining core files.
2158 You can specify the number of lines that the `list' command shows.
2161 * New machines supported (host and target)
2163 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2164 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
2165 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
2167 * New hosts supported (not targets)
2169 IBM RT/PC: romp-ibm-aix or rtpc
2171 * New targets supported (not hosts)
2173 AMD 29000 embedded with COFF a29k-none-coff
2174 AMD 29000 embedded with a.out a29k-none-aout
2175 Ultracomputer remote kernel debug a29k-nyu-kern
2177 * New remote interfaces
2183 *** Changes in GDB-4.0:
2187 Wide output is wrapped at good places to make the output more readable.
2189 Gdb now supports cross-debugging from a host machine of one type to a
2190 target machine of another type. Communication with the target system
2191 is over serial lines. The ``target'' command handles connecting to the
2192 remote system; the ``load'' command will download a program into the
2193 remote system. Serial stubs for the m68k and i386 are provided. Gdb
2194 also supports debugging of realtime processes running under VxWorks,
2195 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
2196 stub on the target system.
2198 New CPUs supported include the AMD 29000 and Intel 960.
2200 GDB now reads object files and symbol tables via a ``binary file''
2201 library, which allows a single copy of GDB to debug programs of multiple
2202 object file types such as a.out and coff.
2204 There is now a GDB reference card in "doc/refcard.tex". (Make targets
2205 refcard.dvi and refcard.ps are available to format it).
2208 * Control-Variable user interface simplified
2210 All variables that control the operation of the debugger can be set
2211 by the ``set'' command, and displayed by the ``show'' command.
2213 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
2214 ``Show prompt'' produces the response:
2215 Gdb's prompt is new-gdb=>.
2217 What follows are the NEW set commands. The command ``help set'' will
2218 print a complete list of old and new set commands. ``help set FOO''
2219 will give a longer description of the variable FOO. ``show'' will show
2220 all of the variable descriptions and their current settings.
2222 confirm on/off: Enables warning questions for operations that are
2223 hard to recover from, e.g. rerunning the program while
2224 it is already running. Default is ON.
2226 editing on/off: Enables EMACS style command line editing
2227 of input. Previous lines can be recalled with
2228 control-P, the current line can be edited with control-B,
2229 you can search for commands with control-R, etc.
2232 history filename NAME: NAME is where the gdb command history
2233 will be stored. The default is .gdb_history,
2234 or the value of the environment variable
2237 history size N: The size, in commands, of the command history. The
2238 default is 256, or the value of the environment variable
2241 history save on/off: If this value is set to ON, the history file will
2242 be saved after exiting gdb. If set to OFF, the
2243 file will not be saved. The default is OFF.
2245 history expansion on/off: If this value is set to ON, then csh-like
2246 history expansion will be performed on
2247 command line input. The default is OFF.
2249 radix N: Sets the default radix for input and output. It can be set
2250 to 8, 10, or 16. Note that the argument to "radix" is interpreted
2251 in the current radix, so "set radix 10" is always a no-op.
2253 height N: This integer value is the number of lines on a page. Default
2254 is 24, the current `stty rows'' setting, or the ``li#''
2255 setting from the termcap entry matching the environment
2258 width N: This integer value is the number of characters on a line.
2259 Default is 80, the current `stty cols'' setting, or the ``co#''
2260 setting from the termcap entry matching the environment
2263 Note: ``set screensize'' is obsolete. Use ``set height'' and
2264 ``set width'' instead.
2266 print address on/off: Print memory addresses in various command displays,
2267 such as stack traces and structure values. Gdb looks
2268 more ``symbolic'' if you turn this off; it looks more
2269 ``machine level'' with it on. Default is ON.
2271 print array on/off: Prettyprint arrays. New convenient format! Default
2274 print demangle on/off: Print C++ symbols in "source" form if on,
2277 print asm-demangle on/off: Same, for assembler level printouts
2280 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
2283 * Support for Epoch Environment.
2285 The epoch environment is a version of Emacs v18 with windowing. One
2286 new command, ``inspect'', is identical to ``print'', except that if you
2287 are running in the epoch environment, the value is printed in its own
2291 * Support for Shared Libraries
2293 GDB can now debug programs and core files that use SunOS shared libraries.
2294 Symbols from a shared library cannot be referenced
2295 before the shared library has been linked with the program (this
2296 happens after you type ``run'' and before the function main() is entered).
2297 At any time after this linking (including when examining core files
2298 from dynamically linked programs), gdb reads the symbols from each
2299 shared library when you type the ``sharedlibrary'' command.
2300 It can be abbreviated ``share''.
2302 sharedlibrary REGEXP: Load shared object library symbols for files
2303 matching a unix regular expression. No argument
2304 indicates to load symbols for all shared libraries.
2306 info sharedlibrary: Status of loaded shared libraries.
2311 A watchpoint stops execution of a program whenever the value of an
2312 expression changes. Checking for this slows down execution
2313 tremendously whenever you are in the scope of the expression, but is
2314 quite useful for catching tough ``bit-spreader'' or pointer misuse
2315 problems. Some machines such as the 386 have hardware for doing this
2316 more quickly, and future versions of gdb will use this hardware.
2318 watch EXP: Set a watchpoint (breakpoint) for an expression.
2320 info watchpoints: Information about your watchpoints.
2322 delete N: Deletes watchpoint number N (same as breakpoints).
2323 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
2324 enable N: Re-enables watchpoint number N (same as breakpoints).
2327 * C++ multiple inheritance
2329 When used with a GCC version 2 compiler, GDB supports multiple inheritance
2332 * C++ exception handling
2334 Gdb now supports limited C++ exception handling. Besides the existing
2335 ability to breakpoint on an exception handler, gdb can breakpoint on
2336 the raising of an exception (before the stack is peeled back to the
2339 catch FOO: If there is a FOO exception handler in the dynamic scope,
2340 set a breakpoint to catch exceptions which may be raised there.
2341 Multiple exceptions (``catch foo bar baz'') may be caught.
2343 info catch: Lists all exceptions which may be caught in the
2344 current stack frame.
2347 * Minor command changes
2349 The command ``call func (arg, arg, ...)'' now acts like the print
2350 command, except it does not print or save a value if the function's result
2351 is void. This is similar to dbx usage.
2353 The ``up'' and ``down'' commands now always print the frame they end up
2354 at; ``up-silently'' and `down-silently'' can be used in scripts to change
2355 frames without printing.
2357 * New directory command
2359 'dir' now adds directories to the FRONT of the source search path.
2360 The path starts off empty. Source files that contain debug information
2361 about the directory in which they were compiled can be found even
2362 with an empty path; Sun CC and GCC include this information. If GDB can't
2363 find your source file in the current directory, type "dir .".
2365 * Configuring GDB for compilation
2367 For normal use, type ``./configure host''. See README or gdb.texinfo
2370 GDB now handles cross debugging. If you are remotely debugging between
2371 two different machines, type ``./configure host -target=targ''.
2372 Host is the machine where GDB will run; targ is the machine
2373 where the program that you are debugging will run.