1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB-4.18:
8 On SVR4 native platforms (such as Solaris), if you attach to a process
9 without first loading a symbol file, GDB will now attempt to locate and
10 load symbols from the running process's executable file.
14 Motorola MCore mcore-*-*
15 x86 VxWorks i[3456]86-*-vxworks*
16 PowerPC VxWorks powerpc-*-vxworks*
17 TI TMS320C80 tic80-*-*
19 * OBSOLETE configurations
21 Altos 3068 m68*-altos-*
26 * Remote targets can connect to a sub-program
28 A popen(3) style serial-device has been added. This device starts a
29 sub-process (such as a stand-alone simulator) and then communicates
30 with that. The sub-program to run is specified using the syntax
31 ``|<program> <args>'' vis:
33 (gdb) set remotedebug 1
34 (gdb) target extended-remote |mn10300-elf-sim program-args
36 * MIPS 64 remote protocol
38 A long standing bug in the mips64 remote protocol where by GDB
39 expected certain 32 bit registers (ex SR) to be transfered as 32
40 instead of 64 bits has been fixed.
42 The command ``set remote-mips64-transfers-32bit-regs on'' has been
43 added to provide backward compatibility with older versions of GDB.
45 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
47 The command ``set remotebinarydownload'' command has been replaced by
48 ``set remote X-packet''. Other commands in ``set remote'' family
49 include ``set remote P-packet''.
51 *** Changes in GDB-4.18:
53 * New native configurations
55 HP-UX 10.20 hppa*-*-hpux10.20
56 HP-UX 11.x hppa*-*-hpux11.0*
57 M68K Linux m68*-*-linux*
61 Fujitsu FR30 fr30-*-elf*
62 Intel StrongARM strongarm-*-*
63 Mitsubishi D30V d30v-*-*
65 * OBSOLETE configurations
67 Gould PowerNode, NP1 np1-*-*, pn-*-*
69 Configurations that have been declared obsolete will be commented out,
70 but the code will be left in place. If there is no activity to revive
71 these configurations before the next release of GDB, the sources will
72 be permanently REMOVED.
76 As a compatibility experiment, GDB's source files buildsym.h and
77 buildsym.c have been converted to pure standard C, no longer
78 containing any K&R compatibility code. We believe that all systems in
79 use today either come with a standard C compiler, or have a GCC port
80 available. If this is not true, please report the affected
81 configuration to bug-gdb@gnu.org immediately. See the README file for
82 information about getting a standard C compiler if you don't have one
87 GDB now uses readline 2.2.
89 * set extension-language
91 You can now control the mapping between filename extensions and source
92 languages by using the `set extension-language' command. For instance,
93 you can ask GDB to treat .c files as C++ by saying
94 set extension-language .c c++
95 The command `info extensions' lists all of the recognized extensions
96 and their associated languages.
98 * Setting processor type for PowerPC and RS/6000
100 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
101 you can use the `set processor' command to specify what variant of the
102 PowerPC family you are debugging. The command
106 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
107 following PowerPC and RS6000 variants:
109 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
110 rs6000 IBM RS6000 ("POWER") architecture, user-level view
112 403GC IBM PowerPC 403GC
113 505 Motorola PowerPC 505
114 860 Motorola PowerPC 860 or 850
115 601 Motorola PowerPC 601
116 602 Motorola PowerPC 602
117 603 Motorola/IBM PowerPC 603 or 603e
118 604 Motorola PowerPC 604 or 604e
119 750 Motorola/IBM PowerPC 750 or 750
121 At the moment, this command just tells GDB what to name the
122 special-purpose processor registers. Since almost all the affected
123 registers are inaccessible to user-level programs, this command is
124 only useful for remote debugging in its present form.
128 Thanks to a major code donation from Hewlett-Packard, GDB now has much
129 more extensive support for HP-UX. Added features include shared
130 library support, kernel threads and hardware watchpoints for 11.00,
131 support for HP's ANSI C and C++ compilers, and a compatibility mode
132 for xdb and dbx commands.
136 HP's donation includes the new concept of catchpoints, which is a
137 generalization of the old catch command. On HP-UX, it is now possible
138 to catch exec, fork, and vfork, as well as library loading.
140 This means that the existing catch command has changed; its first
141 argument now specifies the type of catch to be set up. See the
142 output of "help catch" for a list of catchpoint types.
144 * Debugging across forks
146 On HP-UX, you can choose which process to debug when a fork() happens
151 HP has donated a curses-based terminal user interface (TUI). To get
152 it, build with --enable-tui. Although this can be enabled for any
153 configuration, at present it only works for native HP debugging.
155 * GDB remote protocol additions
157 A new protocol packet 'X' that writes binary data is now available.
158 Default behavior is to try 'X', then drop back to 'M' if the stub
159 fails to respond. The settable variable `remotebinarydownload'
160 allows explicit control over the use of 'X'.
162 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
163 full 64-bit address. The command
165 set remoteaddresssize 32
167 can be used to revert to the old behaviour. For existing remote stubs
168 the change should not be noticed, as the additional address information
171 In order to assist in debugging stubs, you may use the maintenance
172 command `packet' to send any text string to the stub. For instance,
174 maint packet heythere
176 sends the packet "$heythere#<checksum>". Note that it is very easy to
177 disrupt a debugging session by sending the wrong packet at the wrong
180 The compare-sections command allows you to compare section data on the
181 target to what is in the executable file without uploading or
182 downloading, by comparing CRC checksums.
184 * Tracing can collect general expressions
186 You may now collect general expressions at tracepoints. This requires
187 further additions to the target-side stub; see tracepoint.c and
188 doc/agentexpr.texi for further details.
190 * mask-address variable for Mips
192 For Mips targets, you may control the zeroing of the upper 32 bits of
193 a 64-bit address by entering `set mask-address on'. This is mainly
194 of interest to users of embedded R4xxx and R5xxx processors.
196 * Higher serial baud rates
198 GDB's serial code now allows you to specify baud rates 57600, 115200,
199 230400, and 460800 baud. (Note that your host system may not be able
200 to achieve all of these rates.)
204 The i960 configuration now includes an initial implementation of a
205 builtin simulator, contributed by Jim Wilson.
208 *** Changes in GDB-4.17:
210 * New native configurations
212 Alpha GNU/Linux alpha*-*-linux*
213 Unixware 2.x i[3456]86-unixware2*
214 Irix 6.x mips*-sgi-irix6*
215 PowerPC GNU/Linux powerpc-*-linux*
216 PowerPC Solaris powerpcle-*-solaris*
217 Sparc GNU/Linux sparc-*-linux*
218 Motorola sysV68 R3V7.1 m68k-motorola-sysv
222 Argonaut Risc Chip (ARC) arc-*-*
223 Hitachi H8/300S h8300*-*-*
224 Matsushita MN10200 w/simulator mn10200-*-*
225 Matsushita MN10300 w/simulator mn10300-*-*
226 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
227 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
228 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
229 Mitsubishi D10V w/simulator d10v-*-*
230 Mitsubishi M32R/D w/simulator m32r-*-elf*
231 Tsqware Sparclet sparclet-*-*
232 NEC V850 w/simulator v850-*-*
234 * New debugging protocols
236 ARM with RDI protocol arm*-*-*
237 M68K with dBUG monitor m68*-*-{aout,coff,elf}
238 DDB and LSI variants of PMON protocol mips*-*-*
239 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
240 PowerPC with SDS protocol powerpc{,le}-*-eabi
241 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
245 All configurations can now understand and use the DWARF 2 debugging
246 format. The choice is automatic, if the symbol file contains DWARF 2
251 GDB now includes basic Java language support. This support is
252 only useful with Java compilers that produce native machine code.
254 * solib-absolute-prefix and solib-search-path
256 For SunOS and SVR4 shared libraries, you may now set the prefix for
257 loading absolute shared library symbol files, and the search path for
258 locating non-absolute shared library symbol files.
260 * Live range splitting
262 GDB can now effectively debug code for which GCC has performed live
263 range splitting as part of its optimization. See gdb/doc/LRS for
264 more details on the expected format of the stabs information.
268 GDB's support for the GNU Hurd, including thread debugging, has been
269 updated to work with current versions of the Hurd.
273 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
274 instruction set. ARM GDB automatically detects when Thumb
275 instructions are in use, and adjusts disassembly and backtracing
280 GDB's MIPS target configurations now handle the MIP16 16-bit
285 GDB now includes support for overlays; if an executable has been
286 linked such that multiple sections are based at the same address, GDB
287 will decide which section to use for symbolic info. You can choose to
288 control the decision manually, using overlay commands, or implement
289 additional target-side support and use "overlay load-target" to bring
290 in the overlay mapping. Do "help overlay" for more detail.
294 The command "info symbol <address>" displays information about
295 the symbol at the specified address.
299 The standard remote protocol now includes an extension that allows
300 asynchronous collection and display of trace data. This requires
301 extensive support in the target-side debugging stub. Tracing mode
302 includes a new interaction mode in GDB and new commands: see the
303 file tracepoint.c for more details.
307 Configurations for embedded MIPS now include a simulator contributed
308 by Cygnus Solutions. The simulator supports the instruction sets
309 of most MIPS variants.
313 Sparc configurations may now include the ERC32 simulator contributed
314 by the European Space Agency. The simulator is not built into
315 Sparc targets by default; configure with --enable-sim to include it.
319 For target configurations that may include multiple variants of a
320 basic architecture (such as MIPS and SH), you may now set the
321 architecture explicitly. "set arch" sets, "info arch" lists
322 the possible architectures.
324 *** Changes in GDB-4.16:
326 * New native configurations
328 Windows 95, x86 Windows NT i[345]86-*-cygwin32
329 M68K NetBSD m68k-*-netbsd*
330 PowerPC AIX 4.x powerpc-*-aix*
331 PowerPC MacOS powerpc-*-macos*
332 PowerPC Windows NT powerpcle-*-cygwin32
333 RS/6000 AIX 4.x rs6000-*-aix4*
337 ARM with RDP protocol arm-*-*
338 I960 with MON960 i960-*-coff
339 MIPS VxWorks mips*-*-vxworks*
340 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
341 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
343 Matra Sparclet sparclet-*-*
347 The powerpc-eabi configuration now includes the PSIM simulator,
348 contributed by Andrew Cagney, with assistance from Mike Meissner.
349 PSIM is a very elaborate model of the PowerPC, including not only
350 basic instruction set execution, but also details of execution unit
351 performance and I/O hardware. See sim/ppc/README for more details.
355 GDB now works with Solaris 2.5.
357 * Windows 95/NT native
359 GDB will now work as a native debugger on Windows 95 and Windows NT.
360 To build it from source, you must use the "gnu-win32" environment,
361 which uses a DLL to emulate enough of Unix to run the GNU tools.
362 Further information, binaries, and sources are available at
363 ftp.cygnus.com, under pub/gnu-win32.
365 * dont-repeat command
367 If a user-defined command includes the command `dont-repeat', then the
368 command will not be repeated if the user just types return. This is
369 useful if the command is time-consuming to run, so that accidental
370 extra keystrokes don't run the same command many times.
372 * Send break instead of ^C
374 The standard remote protocol now includes an option to send a break
375 rather than a ^C to the target in order to interrupt it. By default,
376 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
378 * Remote protocol timeout
380 The standard remote protocol includes a new variable `remotetimeout'
381 that allows you to set the number of seconds before GDB gives up trying
382 to read from the target. The default value is 2.
384 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
386 By default GDB will automatically keep track of objects as they are
387 loaded and unloaded by the dynamic linker. By using the command `set
388 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
389 when shared library events occur, thus allowing you to set breakpoints
390 in shared libraries which are explicitly loaded by the inferior.
392 Note this feature does not work on hpux8. On hpux9 you must link
393 /usr/lib/end.o into your program. This feature should work
394 automatically on hpux10.
396 * Irix 5.x hardware watchpoint support
398 Irix 5 configurations now support the use of hardware watchpoints.
400 * Mips protocol "SYN garbage limit"
402 When debugging a Mips target using the `target mips' protocol, you
403 may set the number of characters that GDB will ignore by setting
404 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
405 every character. The default value is 1050.
407 * Recording and replaying remote debug sessions
409 If you set `remotelogfile' to the name of a file, gdb will write to it
410 a recording of a remote debug session. This recording may then be
411 replayed back to gdb using "gdbreplay". See gdbserver/README for
412 details. This is useful when you have a problem with GDB while doing
413 remote debugging; you can make a recording of the session and send it
414 to someone else, who can then recreate the problem.
416 * Speedups for remote debugging
418 GDB includes speedups for downloading and stepping MIPS systems using
419 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
420 and more efficient S-record downloading.
422 * Memory use reductions and statistics collection
424 GDB now uses less memory and reports statistics about memory usage.
425 Try the `maint print statistics' command, for example.
427 *** Changes in GDB-4.15:
431 The symbol reader for AIX GDB now uses partial symbol tables. This
432 can greatly improve startup time, especially for large executables.
434 * Remote targets use caching
436 Remote targets now use a data cache to speed up communication with the
437 remote side. The data cache could lead to incorrect results because
438 it doesn't know about volatile variables, thus making it impossible to
439 debug targets which use memory mapped I/O devices. `set remotecache
440 off' turns the the data cache off.
442 * Remote targets may have threads
444 The standard remote protocol now includes support for multiple threads
445 in the target system, using new protocol commands 'H' and 'T'. See
446 gdb/remote.c for details.
450 If GDB is configured with `--enable-netrom', then it will include
451 support for the NetROM ROM emulator from XLNT Designs. The NetROM
452 acts as though it is a bank of ROM on the target board, but you can
453 write into it over the network. GDB's support consists only of
454 support for fast loading into the emulated ROM; to debug, you must use
455 another protocol, such as standard remote protocol. The usual
456 sequence is something like
458 target nrom <netrom-hostname>
460 target remote <netrom-hostname>:1235
464 GDB now includes support for the Apple Macintosh, as a host only. It
465 may be run as either an MPW tool or as a standalone application, and
466 it can debug through the serial port. All the usual GDB commands are
467 available, but to the target command, you must supply "serial" as the
468 device type instead of "/dev/ttyXX". See mpw-README in the main
469 directory for more information on how to build. The MPW configuration
470 scripts */mpw-config.in support only a few targets, and only the
471 mips-idt-ecoff target has been tested.
475 GDB configuration now uses autoconf. This is not user-visible,
476 but does simplify configuration and building.
480 GDB now supports hpux10.
482 *** Changes in GDB-4.14:
484 * New native configurations
486 x86 FreeBSD i[345]86-*-freebsd
487 x86 NetBSD i[345]86-*-netbsd
488 NS32k NetBSD ns32k-*-netbsd
489 Sparc NetBSD sparc-*-netbsd
493 A29K VxWorks a29k-*-vxworks
494 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
495 CPU32 EST-300 emulator m68*-*-est*
496 PowerPC ELF powerpc-*-elf
499 * Alpha OSF/1 support for procfs
501 GDB now supports procfs under OSF/1-2.x and higher, which makes it
502 possible to attach to running processes. As the mounting of the /proc
503 filesystem is optional on the Alpha, GDB automatically determines
504 the availability of /proc during startup. This can lead to problems
505 if /proc is unmounted after GDB has been started.
507 * Arguments to user-defined commands
509 User commands may accept up to 10 arguments separated by whitespace.
510 Arguments are accessed within the user command via $arg0..$arg9. A
513 print $arg0 + $arg1 + $arg2
515 To execute the command use:
518 Defines the command "adder" which prints the sum of its three arguments.
519 Note the arguments are text substitutions, so they may reference variables,
520 use complex expressions, or even perform inferior function calls.
522 * New `if' and `while' commands
524 This makes it possible to write more sophisticated user-defined
525 commands. Both commands take a single argument, which is the
526 expression to evaluate, and must be followed by the commands to
527 execute, one per line, if the expression is nonzero, the list being
528 terminated by the word `end'. The `if' command list may include an
529 `else' word, which causes the following commands to be executed only
530 if the expression is zero.
532 * Fortran source language mode
534 GDB now includes partial support for Fortran 77. It will recognize
535 Fortran programs and can evaluate a subset of Fortran expressions, but
536 variables and functions may not be handled correctly. GDB will work
537 with G77, but does not yet know much about symbols emitted by other
540 * Better HPUX support
542 Most debugging facilities now work on dynamic executables for HPPAs
543 running hpux9 or later. You can attach to running dynamically linked
544 processes, but by default the dynamic libraries will be read-only, so
545 for instance you won't be able to put breakpoints in them. To change
546 that behavior do the following before running the program:
552 This will cause the libraries to be mapped private and read-write.
553 To revert to the normal behavior, do this:
559 You cannot set breakpoints or examine data in the library until after
560 the library is loaded if the function/data symbols do not have
563 GDB can now also read debug symbols produced by the HP C compiler on
564 HPPAs (sorry, no C++, Fortran or 68k support).
566 * Target byte order now dynamically selectable
568 You can choose which byte order to use with a target system, via the
569 commands "set endian big" and "set endian little", and you can see the
570 current setting by using "show endian". You can also give the command
571 "set endian auto", in which case GDB will use the byte order
572 associated with the executable. Currently, only embedded MIPS
573 configurations support dynamic selection of target byte order.
575 * New DOS host serial code
577 This version uses DPMI interrupts to handle buffered I/O, so you
578 no longer need to run asynctsr when debugging boards connected to
581 *** Changes in GDB-4.13:
583 * New "complete" command
585 This lists all the possible completions for the rest of the line, if it
586 were to be given as a command itself. This is intended for use by emacs.
588 * Trailing space optional in prompt
590 "set prompt" no longer adds a space for you after the prompt you set. This
591 allows you to set a prompt which ends in a space or one that does not.
593 * Breakpoint hit counts
595 "info break" now displays a count of the number of times the breakpoint
596 has been hit. This is especially useful in conjunction with "ignore"; you
597 can ignore a large number of breakpoint hits, look at the breakpoint info
598 to see how many times the breakpoint was hit, then run again, ignoring one
599 less than that number, and this will get you quickly to the last hit of
602 * Ability to stop printing at NULL character
604 "set print null-stop" will cause GDB to stop printing the characters of
605 an array when the first NULL is encountered. This is useful when large
606 arrays actually contain only short strings.
608 * Shared library breakpoints
610 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
611 breakpoints in shared libraries before the executable is run.
613 * Hardware watchpoints
615 There is a new hardware breakpoint for the watch command for sparclite
616 targets. See gdb/sparclite/hw_breakpoint.note.
618 Hardware watchpoints are also now supported under Linux.
622 Annotations have been added. These are for use with graphical interfaces,
623 and are still experimental. Currently only gdba.el uses these.
625 * Improved Irix 5 support
627 GDB now works properly with Irix 5.2.
629 * Improved HPPA support
631 GDB now works properly with the latest GCC and GAS.
633 * New native configurations
635 Sequent PTX4 i[34]86-sequent-ptx4
636 HPPA running OSF/1 hppa*-*-osf*
637 Atari TT running SVR4 m68*-*-sysv4*
638 RS/6000 LynxOS rs6000-*-lynxos*
642 OS/9000 i[34]86-*-os9k
643 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
646 * Hitachi SH7000 and E7000-PC ICE support
648 There is now support for communicating with the Hitachi E7000-PC ICE.
649 This is available automatically when GDB is configured for the SH.
653 As usual, a variety of small fixes and improvements, both generic
654 and configuration-specific. See the ChangeLog for more detail.
656 *** Changes in GDB-4.12:
658 * Irix 5 is now supported
662 GDB-4.12 on the HPPA has a number of changes which make it unable
663 to debug the output from the currently released versions of GCC and
664 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
665 of GCC and GAS, versions of these tools designed to work with GDB-4.12
666 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
669 *** Changes in GDB-4.11:
671 * User visible changes:
675 The "set remotedebug" option is now consistent between the mips remote
676 target, remote targets using the gdb-specific protocol, UDI (AMD's
677 debug protocol for the 29k) and the 88k bug monitor. It is now an
678 integer specifying a debug level (normally 0 or 1, but 2 means more
679 debugging info for the mips target).
681 * DEC Alpha native support
683 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
684 debug info, but GDB works fairly well with the DEC compiler and should
685 work with a future GCC release. See the README file for a few
686 Alpha-specific notes.
688 * Preliminary thread implementation
690 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
692 * LynxOS native and target support for 386
694 This release has been hosted on LynxOS 2.2, and also can be configured
695 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
698 * Improvements in C++ mangling/demangling.
700 This release has much better g++ debugging, specifically in name
701 mangling/demangling, virtual function calls, print virtual table,
702 call methods, ...etc.
704 *** Changes in GDB-4.10:
706 * User visible changes:
708 Remote debugging using the GDB-specific (`target remote') protocol now
709 supports the `load' command. This is only useful if you have some
710 other way of getting the stub to the target system, and you can put it
711 somewhere in memory where it won't get clobbered by the download.
713 Filename completion now works.
715 When run under emacs mode, the "info line" command now causes the
716 arrow to point to the line specified. Also, "info line" prints
717 addresses in symbolic form (as well as hex).
719 All vxworks based targets now support a user settable option, called
720 vxworks-timeout. This option represents the number of seconds gdb
721 should wait for responses to rpc's. You might want to use this if
722 your vxworks target is, perhaps, a slow software simulator or happens
723 to be on the far side of a thin network line.
727 This release contains support for using a DEC alpha as a GDB host for
728 cross debugging. Native alpha debugging is not supported yet.
731 *** Changes in GDB-4.9:
735 This is the first GDB release which is accompanied by a matching testsuite.
736 The testsuite requires installation of dejagnu, which should be available
737 via ftp from most sites that carry GNU software.
741 'Cfront' style demangling has had its name changed to 'ARM' style, to
742 emphasize that it was written from the specifications in the C++ Annotated
743 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
744 disclaimers, it still generated too much confusion with users attempting to
745 use gdb with AT&T cfront.
749 GDB now uses a standard remote interface to a simulator library.
750 So far, the library contains simulators for the Zilog Z8001/2, the
751 Hitachi H8/300, H8/500 and Super-H.
753 * New targets supported
755 H8/300 simulator h8300-hitachi-hms or h8300hms
756 H8/500 simulator h8500-hitachi-hms or h8500hms
757 SH simulator sh-hitachi-hms or sh
758 Z8000 simulator z8k-zilog-none or z8ksim
759 IDT MIPS board over serial line mips-idt-ecoff
761 Cross-debugging to GO32 targets is supported. It requires a custom
762 version of the i386-stub.c module which is integrated with the
763 GO32 memory extender.
765 * New remote protocols
767 MIPS remote debugging protocol.
769 * New source languages supported
771 This version includes preliminary support for Chill, a Pascal like language
772 used by telecommunications companies. Chill support is also being integrated
773 into the GNU compiler, but we don't know when it will be publically available.
776 *** Changes in GDB-4.8:
778 * HP Precision Architecture supported
780 GDB now supports HP PA-RISC machines running HPUX. A preliminary
781 version of this support was available as a set of patches from the
782 University of Utah. GDB does not support debugging of programs
783 compiled with the HP compiler, because HP will not document their file
784 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
785 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
787 Many problems in the preliminary version have been fixed.
789 * Faster and better demangling
791 We have improved template demangling and fixed numerous bugs in the GNU style
792 demangler. It can now handle type modifiers such as `static' or `const'. Wide
793 character types (wchar_t) are now supported. Demangling of each symbol is now
794 only done once, and is cached when the symbol table for a file is read in.
795 This results in a small increase in memory usage for C programs, a moderate
796 increase in memory usage for C++ programs, and a fantastic speedup in
799 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
800 from the specifications in the Annotated Reference Manual, which AT&T's
801 compiler does not actually implement.
803 * G++ multiple inheritance compiler problem
805 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
806 inheritance lattices was reworked to properly discover ambiguities. We
807 recently found an example which causes this new algorithm to fail in a
808 very subtle way, producing bad debug information for those classes.
809 The file 'gcc.patch' (in this directory) can be applied to gcc to
810 circumvent the problem. A future GCC release will contain a complete
813 The previous G++ debug info problem (mentioned below for the gdb-4.7
814 release) is fixed in gcc version 2.3.2.
816 * Improved configure script
818 The `configure' script will now attempt to guess your system type if
819 you don't supply a host system type. The old scheme of supplying a
820 host system triplet is preferable over using this. All the magic is
821 done in the new `config.guess' script. Examine it for details.
823 We have also brought our configure script much more in line with the FSF's
824 version. It now supports the --with-xxx options. In particular,
825 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
826 The resulting GDB will not be able to read arbitrary object file formats --
827 only the format ``expected'' to be used on the configured target system.
828 We hope to make this the default in a future release.
830 * Documentation improvements
832 There's new internal documentation on how to modify GDB, and how to
833 produce clean changes to the code. We implore people to read it
834 before submitting changes.
836 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
837 M4 macros. The new texinfo.tex is provided in this release. Pre-built
838 `info' files are also provided. To build `info' files from scratch,
839 you will need the latest `makeinfo' release, which will be available in
840 a future texinfo-X.Y release.
842 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
843 We're not sure exactly which versions have this problem, but it has
844 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
845 or better. If that isn't possible, there is a patch in
846 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
851 GDB now supports array constants that can be used in expressions typed in by
852 the user. The syntax is `{element, element, ...}'. Ie: you can now type
853 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
856 The new directory `gdb/sparclite' contains a program that demonstrates
857 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
859 * New native hosts supported
861 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
862 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
864 * New targets supported
866 AMD 29k family via UDI a29k-amd-udi or udi29k
868 * New file formats supported
870 BFD now supports reading HP/PA-RISC executables (SOM file format?),
871 HPUX core files, and SCO 3.2v2 core files.
875 Attaching to processes now works again; thanks for the many bug reports.
877 We have also stomped on a bunch of core dumps caused by
878 printf_filtered("%s") problems.
880 We eliminated a copyright problem on the rpc and ptrace header files
881 for VxWorks, which was discovered at the last minute during the 4.7
882 release. You should now be able to build a VxWorks GDB.
884 You can now interrupt gdb while an attached process is running. This
885 will cause the attached process to stop, and give control back to GDB.
887 We fixed problems caused by using too many file descriptors
888 for reading symbols from object files and libraries. This was
889 especially a problem for programs that used many (~100) shared
892 The `step' command now only enters a subroutine if there is line number
893 information for the subroutine. Otherwise it acts like the `next'
894 command. Previously, `step' would enter subroutines if there was
895 any debugging information about the routine. This avoids problems
896 when using `cc -g1' on MIPS machines.
898 * Internal improvements
900 GDB's internal interfaces have been improved to make it easier to support
901 debugging of multiple languages in the future.
903 GDB now uses a common structure for symbol information internally.
904 Minimal symbols (derived from linkage symbols in object files), partial
905 symbols (from a quick scan of debug information), and full symbols
906 contain a common subset of information, making it easier to write
907 shared code that handles any of them.
909 * New command line options
911 We now accept --silent as an alias for --quiet.
915 The memory-mapped-malloc library is now licensed under the GNU Library
916 General Public License.
918 *** Changes in GDB-4.7:
920 * Host/native/target split
922 GDB has had some major internal surgery to untangle the support for
923 hosts and remote targets. Now, when you configure GDB for a remote
924 target, it will no longer load in all of the support for debugging
925 local programs on the host. When fully completed and tested, this will
926 ensure that arbitrary host/target combinations are possible.
928 The primary conceptual shift is to separate the non-portable code in
929 GDB into three categories. Host specific code is required any time GDB
930 is compiled on that host, regardless of the target. Target specific
931 code relates to the peculiarities of the target, but can be compiled on
932 any host. Native specific code is everything else: it can only be
933 built when the host and target are the same system. Child process
934 handling and core file support are two common `native' examples.
936 GDB's use of /proc for controlling Unix child processes is now cleaner.
937 It has been split out into a single module under the `target_ops' vector,
938 plus two native-dependent functions for each system that uses /proc.
940 * New hosts supported
942 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
943 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
944 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
946 * New targets supported
948 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
949 68030 and CPU32 m68030-*-*, m68332-*-*
951 * New native hosts supported
953 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
954 (386bsd is not well tested yet)
955 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
957 * New file formats supported
959 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
960 supports reading of `a.out.adobe' object files, which are an a.out
961 format extended with minimal information about multiple sections.
965 `show copying' is the same as the old `info copying'.
966 `show warranty' is the same as `info warrantee'.
967 These were renamed for consistency. The old commands continue to work.
969 `info handle' is a new alias for `info signals'.
971 You can now define pre-command hooks, which attach arbitrary command
972 scripts to any command. The commands in the hook will be executed
973 prior to the user's command. You can also create a hook which will be
974 executed whenever the program stops. See gdb.texinfo.
978 We now deal with Cfront style name mangling, and can even extract type
979 info from mangled symbols. GDB can automatically figure out which
980 symbol mangling style your C++ compiler uses.
982 Calling of methods and virtual functions has been improved as well.
986 The crash that occured when debugging Sun Ansi-C compiled binaries is
987 fixed. This was due to mishandling of the extra N_SO stabs output
990 We also finally got Ultrix 4.2 running in house, and fixed core file
991 support, with help from a dozen people on the net.
993 John M. Farrell discovered that the reason that single-stepping was so
994 slow on all of the Mips based platforms (primarily SGI and DEC) was
995 that we were trying to demangle and lookup a symbol used for internal
996 purposes on every instruction that was being stepped through. Changing
997 the name of that symbol so that it couldn't be mistaken for a C++
998 mangled symbol sped things up a great deal.
1000 Rich Pixley sped up symbol lookups in general by getting much smarter
1001 about when C++ symbol mangling is necessary. This should make symbol
1002 completion (TAB on the command line) much faster. It's not as fast as
1003 we'd like, but it's significantly faster than gdb-4.6.
1007 A new user controllable variable 'call_scratch_address' can
1008 specify the location of a scratch area to be used when GDB
1009 calls a function in the target. This is necessary because the
1010 usual method of putting the scratch area on the stack does not work
1011 in systems that have separate instruction and data spaces.
1013 We integrated changes to support the 29k UDI (Universal Debugger
1014 Interface), but discovered at the last minute that we didn't have all
1015 of the appropriate copyright paperwork. We are working with AMD to
1016 resolve this, and hope to have it available soon.
1020 We have sped up the remote serial line protocol, especially for targets
1021 with lots of registers. It now supports a new `expedited status' ('T')
1022 message which can be used in place of the existing 'S' status message.
1023 This allows the remote stub to send only the registers that GDB
1024 needs to make a quick decision about single-stepping or conditional
1025 breakpoints, eliminating the need to fetch the entire register set for
1026 each instruction being stepped through.
1028 The GDB remote serial protocol now implements a write-through cache for
1029 registers, only re-reading the registers if the target has run.
1031 There is also a new remote serial stub for SPARC processors. You can
1032 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1033 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1034 processor with a serial port.
1038 Configure.in files have become much easier to read and modify. A new
1039 `table driven' format makes it more obvious what configurations are
1040 supported, and what files each one uses.
1044 There is a new opcodes library which will eventually contain all of the
1045 disassembly routines and opcode tables. At present, it only contains
1046 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1047 disassembler (binutils/objdump) to share these routines.
1049 The libiberty library is now copylefted under the GNU Library General
1050 Public License. This allows more liberal use, and was done so libg++
1051 can use it. This makes no difference to GDB, since the Library License
1052 grants all the rights from the General Public License.
1056 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1057 reference to the stabs symbol info used by the debugger. It is (as far
1058 as we know) the only published document on this fascinating topic. We
1059 encourage you to read it, compare it to the stabs information on your
1060 system, and send improvements on the document in general (to
1061 bug-gdb@prep.ai.mit.edu).
1063 And, of course, many bugs have been fixed.
1066 *** Changes in GDB-4.6:
1068 * Better support for C++ function names
1070 GDB now accepts as input the "demangled form" of C++ overloaded function
1071 names and member function names, and can do command completion on such names
1072 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1073 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1074 Make use of command completion, it is your friend.
1076 GDB also now accepts a variety of C++ mangled symbol formats. They are
1077 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1078 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1079 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1080 for the list of formats.
1082 * G++ symbol mangling problem
1084 Recent versions of gcc have a bug in how they emit debugging information for
1085 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1086 directory) can be applied to gcc to fix the problem. Alternatively, if you
1087 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1088 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1089 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1092 * New 'maintenance' command
1094 All of the commands related to hacking GDB internals have been moved out of
1095 the main command set, and now live behind the 'maintenance' command. This
1096 can also be abbreviated as 'mt'. The following changes were made:
1098 dump-me -> maintenance dump-me
1099 info all-breakpoints -> maintenance info breakpoints
1100 printmsyms -> maintenance print msyms
1101 printobjfiles -> maintenance print objfiles
1102 printpsyms -> maintenance print psymbols
1103 printsyms -> maintenance print symbols
1105 The following commands are new:
1107 maintenance demangle Call internal GDB demangler routine to
1108 demangle a C++ link name and prints the result.
1109 maintenance print type Print a type chain for a given symbol
1111 * Change to .gdbinit file processing
1113 We now read the $HOME/.gdbinit file before processing the argv arguments
1114 (e.g. reading symbol files or core files). This allows global parameters to
1115 be set, which will apply during the symbol reading. The ./.gdbinit is still
1116 read after argv processing.
1118 * New hosts supported
1120 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1122 Linux support i386-unknown-linux or linux
1124 We are also including code to support the HP/PA running BSD and HPUX. This
1125 is almost guaranteed not to work, as we didn't have time to test or build it
1126 for this release. We are including it so that the more adventurous (or
1127 masochistic) of you can play with it. We also had major problems with the
1128 fact that the compiler that we got from HP doesn't support the -g option.
1131 * New targets supported
1133 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1135 * More smarts about finding #include files
1137 GDB now remembers the compilation directory for all include files, and for
1138 all files from which C is generated (like yacc and lex sources). This
1139 greatly improves GDB's ability to find yacc/lex sources, and include files,
1140 especially if you are debugging your program from a directory different from
1141 the one that contains your sources.
1143 We also fixed a bug which caused difficulty with listing and setting
1144 breakpoints in include files which contain C code. (In the past, you had to
1145 try twice in order to list an include file that you hadn't looked at before.)
1147 * Interesting infernals change
1149 GDB now deals with arbitrary numbers of sections, where the symbols for each
1150 section must be relocated relative to that section's landing place in the
1151 target's address space. This work was needed to support ELF with embedded
1152 stabs used by Solaris-2.0.
1154 * Bug fixes (of course!)
1156 There have been loads of fixes for the following things:
1157 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1158 i960, stabs, DOS(GO32), procfs, etc...
1160 See the ChangeLog for details.
1162 *** Changes in GDB-4.5:
1164 * New machines supported (host and target)
1166 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1168 SGI Irix-4.x mips-sgi-irix4 or iris4
1170 * New malloc package
1172 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1173 Mmalloc is capable of handling mutiple heaps of memory. It is also
1174 capable of saving a heap to a file, and then mapping it back in later.
1175 This can be used to greatly speedup the startup of GDB by using a
1176 pre-parsed symbol table which lives in a mmalloc managed heap. For
1177 more details, please read mmalloc/mmalloc.texi.
1181 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1182 'help info proc' for details.
1184 * MIPS ecoff symbol table format
1186 The code that reads MIPS symbol table format is now supported on all hosts.
1187 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1190 * File name changes for MS-DOS
1192 Many files in the config directories have been renamed to make it easier to
1193 support GDB on MS-DOSe systems (which have very restrictive file name
1194 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1195 environment) is close to working but has some remaining problems. Note
1196 that debugging of DOS programs is not supported, due to limitations
1197 in the ``operating system'', but it can be used to host cross-debugging.
1199 * Cross byte order fixes
1201 Many fixes have been made to support cross debugging of Sparc and MIPS
1202 targets from hosts whose byte order differs.
1204 * New -mapped and -readnow options
1206 If memory-mapped files are available on your system through the 'mmap'
1207 system call, you can use the -mapped option on the `file' or
1208 `symbol-file' commands to cause GDB to write the symbols from your
1209 program into a reusable file. If the program you are debugging is
1210 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1211 Future GDB debugging sessions will notice the presence of this file,
1212 and will quickly map in symbol information from it, rather than reading
1213 the symbol table from the executable program. Using the '-mapped'
1214 option in a GDB `file' or `symbol-file' command has the same effect as
1215 starting GDB with the '-mapped' command-line option.
1217 You can cause GDB to read the entire symbol table immediately by using
1218 the '-readnow' option with any of the commands that load symbol table
1219 information (or on the GDB command line). This makes the command
1220 slower, but makes future operations faster.
1222 The -mapped and -readnow options are typically combined in order to
1223 build a `fred.syms' file that contains complete symbol information.
1224 A simple GDB invocation to do nothing but build a `.syms' file for future
1227 gdb -batch -nx -mapped -readnow programname
1229 The `.syms' file is specific to the host machine on which GDB is run.
1230 It holds an exact image of GDB's internal symbol table. It cannot be
1231 shared across multiple host platforms.
1233 * longjmp() handling
1235 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1236 siglongjmp() without losing control. This feature has not yet been ported to
1237 all systems. It currently works on many 386 platforms, all MIPS-based
1238 platforms (SGI, DECstation, etc), and Sun3/4.
1242 Preliminary work has been put in to support the new Solaris OS from Sun. At
1243 this time, it can control and debug processes, but it is not capable of
1248 As always, many many bug fixes. The major areas were with g++, and mipsread.
1249 People using the MIPS-based platforms should experience fewer mysterious
1250 crashes and trashed symbol tables.
1252 *** Changes in GDB-4.4:
1254 * New machines supported (host and target)
1256 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1258 BSD Reno on Vax vax-dec-bsd
1259 Ultrix on Vax vax-dec-ultrix
1261 * New machines supported (target)
1263 AMD 29000 embedded, using EBMON a29k-none-none
1267 GDB continues to improve its handling of C++. `References' work better.
1268 The demangler has also been improved, and now deals with symbols mangled as
1269 per the Annotated C++ Reference Guide.
1271 GDB also now handles `stabs' symbol information embedded in MIPS
1272 `ecoff' symbol tables. Since the ecoff format was not easily
1273 extensible to handle new languages such as C++, this appeared to be a
1274 good way to put C++ debugging info into MIPS binaries. This option
1275 will be supported in the GNU C compiler, version 2, when it is
1278 * New features for SVR4
1280 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1281 shared libraries. Debugging dynamically linked programs should present
1282 only minor differences from debugging statically linked programs.
1284 The `info proc' command will print out information about any process
1285 on an SVR4 system (including the one you are debugging). At the moment,
1286 it prints the address mappings of the process.
1288 If you bring up GDB on another SVR4 system, please send mail to
1289 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1291 * Better dynamic linking support in SunOS
1293 Reading symbols from shared libraries which contain debugging symbols
1294 now works properly. However, there remain issues such as automatic
1295 skipping of `transfer vector' code during function calls, which
1296 make it harder to debug code in a shared library, than to debug the
1297 same code linked statically.
1301 GDB is now using the latest `getopt' routines from the FSF. This
1302 version accepts the -- prefix for options with long names. GDB will
1303 continue to accept the old forms (-option and +option) as well.
1304 Various single letter abbreviations for options have been explicity
1305 added to the option table so that they won't get overshadowed in the
1306 future by other options that begin with the same letter.
1310 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1311 Many assorted bugs have been handled. Many more remain to be handled.
1312 See the various ChangeLog files (primarily in gdb and bfd) for details.
1315 *** Changes in GDB-4.3:
1317 * New machines supported (host and target)
1319 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1320 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1321 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1323 * Almost SCO Unix support
1325 We had hoped to support:
1326 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1327 (except for core file support), but we discovered very late in the release
1328 that it has problems with process groups that render gdb unusable. Sorry
1329 about that. I encourage people to fix it and post the fixes.
1331 * Preliminary ELF and DWARF support
1333 GDB can read ELF object files on System V Release 4, and can handle
1334 debugging records for C, in DWARF format, in ELF files. This support
1335 is preliminary. If you bring up GDB on another SVR4 system, please
1336 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1341 GDB now uses the latest `readline' library. One user-visible change
1342 is that two tabs will list possible command completions, which previously
1343 required typing M-? (meta-question mark, or ESC ?).
1347 The `stepi' bug that many of you noticed has been squashed.
1348 Many bugs in C++ have been handled. Many more remain to be handled.
1349 See the various ChangeLog files (primarily in gdb and bfd) for details.
1351 * State of the MIPS world (in case you wondered):
1353 GDB can understand the symbol tables emitted by the compilers
1354 supplied by most vendors of MIPS-based machines, including DEC. These
1355 symbol tables are in a format that essentially nobody else uses.
1357 Some versions of gcc come with an assembler post-processor called
1358 mips-tfile. This program is required if you want to do source-level
1359 debugging of gcc-compiled programs. I believe FSF does not ship
1360 mips-tfile with gcc version 1, but it will eventually come with gcc
1363 Debugging of g++ output remains a problem. g++ version 1.xx does not
1364 really support it at all. (If you're lucky, you should be able to get
1365 line numbers and stack traces to work, but no parameters or local
1366 variables.) With some work it should be possible to improve the
1369 When gcc version 2 is released, you will have somewhat better luck.
1370 However, even then you will get confusing results for inheritance and
1373 We will eventually provide full debugging of g++ output on
1374 DECstations. This will probably involve some kind of stabs-in-ecoff
1375 encapulation, but the details have not been worked out yet.
1378 *** Changes in GDB-4.2:
1380 * Improved configuration
1382 Only one copy of `configure' exists now, and it is not self-modifying.
1383 Porting BFD is simpler.
1387 The `step' and `next' commands now only stop at the first instruction
1388 of a source line. This prevents the multiple stops that used to occur
1389 in switch statements, for-loops, etc. `Step' continues to stop if a
1390 function that has debugging information is called within the line.
1394 Lots of small bugs fixed. More remain.
1396 * New host supported (not target)
1398 Intel 386 PC clone running Mach i386-none-mach
1401 *** Changes in GDB-4.1:
1403 * Multiple source language support
1405 GDB now has internal scaffolding to handle several source languages.
1406 It determines the type of each source file from its filename extension,
1407 and will switch expression parsing and number formatting to match the
1408 language of the function in the currently selected stack frame.
1409 You can also specifically set the language to be used, with
1410 `set language c' or `set language modula-2'.
1414 GDB now has preliminary support for the GNU Modula-2 compiler,
1415 currently under development at the State University of New York at
1416 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1417 continue through the fall of 1991 and into 1992.
1419 Other Modula-2 compilers are currently not supported, and attempting to
1420 debug programs compiled with them will likely result in an error as the
1421 symbol table is read. Feel free to work on it, though!
1423 There are hooks in GDB for strict type checking and range checking,
1424 in the `Modula-2 philosophy', but they do not currently work.
1428 GDB can now write to executable and core files (e.g. patch
1429 a variable's value). You must turn this switch on, specify
1430 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1431 by assigning a new value to a variable. Modifications take
1434 * Automatic SunOS shared library reading
1436 When you run your program, GDB automatically determines where its
1437 shared libraries (if any) have been loaded, and reads their symbols.
1438 The `share' command is no longer needed. This also works when
1439 examining core files.
1443 You can specify the number of lines that the `list' command shows.
1446 * New machines supported (host and target)
1448 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1449 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1450 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1452 * New hosts supported (not targets)
1454 IBM RT/PC: romp-ibm-aix or rtpc
1456 * New targets supported (not hosts)
1458 AMD 29000 embedded with COFF a29k-none-coff
1459 AMD 29000 embedded with a.out a29k-none-aout
1460 Ultracomputer remote kernel debug a29k-nyu-kern
1462 * New remote interfaces
1468 *** Changes in GDB-4.0:
1472 Wide output is wrapped at good places to make the output more readable.
1474 Gdb now supports cross-debugging from a host machine of one type to a
1475 target machine of another type. Communication with the target system
1476 is over serial lines. The ``target'' command handles connecting to the
1477 remote system; the ``load'' command will download a program into the
1478 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1479 also supports debugging of realtime processes running under VxWorks,
1480 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1481 stub on the target system.
1483 New CPUs supported include the AMD 29000 and Intel 960.
1485 GDB now reads object files and symbol tables via a ``binary file''
1486 library, which allows a single copy of GDB to debug programs of multiple
1487 object file types such as a.out and coff.
1489 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1490 refcard.dvi and refcard.ps are available to format it).
1493 * Control-Variable user interface simplified
1495 All variables that control the operation of the debugger can be set
1496 by the ``set'' command, and displayed by the ``show'' command.
1498 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1499 ``Show prompt'' produces the response:
1500 Gdb's prompt is new-gdb=>.
1502 What follows are the NEW set commands. The command ``help set'' will
1503 print a complete list of old and new set commands. ``help set FOO''
1504 will give a longer description of the variable FOO. ``show'' will show
1505 all of the variable descriptions and their current settings.
1507 confirm on/off: Enables warning questions for operations that are
1508 hard to recover from, e.g. rerunning the program while
1509 it is already running. Default is ON.
1511 editing on/off: Enables EMACS style command line editing
1512 of input. Previous lines can be recalled with
1513 control-P, the current line can be edited with control-B,
1514 you can search for commands with control-R, etc.
1517 history filename NAME: NAME is where the gdb command history
1518 will be stored. The default is .gdb_history,
1519 or the value of the environment variable
1522 history size N: The size, in commands, of the command history. The
1523 default is 256, or the value of the environment variable
1526 history save on/off: If this value is set to ON, the history file will
1527 be saved after exiting gdb. If set to OFF, the
1528 file will not be saved. The default is OFF.
1530 history expansion on/off: If this value is set to ON, then csh-like
1531 history expansion will be performed on
1532 command line input. The default is OFF.
1534 radix N: Sets the default radix for input and output. It can be set
1535 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1536 in the current radix, so "set radix 10" is always a no-op.
1538 height N: This integer value is the number of lines on a page. Default
1539 is 24, the current `stty rows'' setting, or the ``li#''
1540 setting from the termcap entry matching the environment
1543 width N: This integer value is the number of characters on a line.
1544 Default is 80, the current `stty cols'' setting, or the ``co#''
1545 setting from the termcap entry matching the environment
1548 Note: ``set screensize'' is obsolete. Use ``set height'' and
1549 ``set width'' instead.
1551 print address on/off: Print memory addresses in various command displays,
1552 such as stack traces and structure values. Gdb looks
1553 more ``symbolic'' if you turn this off; it looks more
1554 ``machine level'' with it on. Default is ON.
1556 print array on/off: Prettyprint arrays. New convenient format! Default
1559 print demangle on/off: Print C++ symbols in "source" form if on,
1562 print asm-demangle on/off: Same, for assembler level printouts
1565 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1568 * Support for Epoch Environment.
1570 The epoch environment is a version of Emacs v18 with windowing. One
1571 new command, ``inspect'', is identical to ``print'', except that if you
1572 are running in the epoch environment, the value is printed in its own
1576 * Support for Shared Libraries
1578 GDB can now debug programs and core files that use SunOS shared libraries.
1579 Symbols from a shared library cannot be referenced
1580 before the shared library has been linked with the program (this
1581 happens after you type ``run'' and before the function main() is entered).
1582 At any time after this linking (including when examining core files
1583 from dynamically linked programs), gdb reads the symbols from each
1584 shared library when you type the ``sharedlibrary'' command.
1585 It can be abbreviated ``share''.
1587 sharedlibrary REGEXP: Load shared object library symbols for files
1588 matching a unix regular expression. No argument
1589 indicates to load symbols for all shared libraries.
1591 info sharedlibrary: Status of loaded shared libraries.
1596 A watchpoint stops execution of a program whenever the value of an
1597 expression changes. Checking for this slows down execution
1598 tremendously whenever you are in the scope of the expression, but is
1599 quite useful for catching tough ``bit-spreader'' or pointer misuse
1600 problems. Some machines such as the 386 have hardware for doing this
1601 more quickly, and future versions of gdb will use this hardware.
1603 watch EXP: Set a watchpoint (breakpoint) for an expression.
1605 info watchpoints: Information about your watchpoints.
1607 delete N: Deletes watchpoint number N (same as breakpoints).
1608 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1609 enable N: Re-enables watchpoint number N (same as breakpoints).
1612 * C++ multiple inheritance
1614 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1617 * C++ exception handling
1619 Gdb now supports limited C++ exception handling. Besides the existing
1620 ability to breakpoint on an exception handler, gdb can breakpoint on
1621 the raising of an exception (before the stack is peeled back to the
1624 catch FOO: If there is a FOO exception handler in the dynamic scope,
1625 set a breakpoint to catch exceptions which may be raised there.
1626 Multiple exceptions (``catch foo bar baz'') may be caught.
1628 info catch: Lists all exceptions which may be caught in the
1629 current stack frame.
1632 * Minor command changes
1634 The command ``call func (arg, arg, ...)'' now acts like the print
1635 command, except it does not print or save a value if the function's result
1636 is void. This is similar to dbx usage.
1638 The ``up'' and ``down'' commands now always print the frame they end up
1639 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1640 frames without printing.
1642 * New directory command
1644 'dir' now adds directories to the FRONT of the source search path.
1645 The path starts off empty. Source files that contain debug information
1646 about the directory in which they were compiled can be found even
1647 with an empty path; Sun CC and GCC include this information. If GDB can't
1648 find your source file in the current directory, type "dir .".
1650 * Configuring GDB for compilation
1652 For normal use, type ``./configure host''. See README or gdb.texinfo
1655 GDB now handles cross debugging. If you are remotely debugging between
1656 two different machines, type ``./configure host -target=targ''.
1657 Host is the machine where GDB will run; targ is the machine
1658 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob