1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB-4.18:
6 * New native configurations
8 ARM GNU/Linux arm*-*-linux*
9 PowerPC GNU/Linux powerpc-*-linux*
13 Motorola MCore mcore-*-*
14 x86 VxWorks i[3456]86-*-vxworks*
15 PowerPC VxWorks powerpc-*-vxworks*
16 TI TMS320C80 tic80-*-*
18 * OBSOLETE configurations
20 Altos 3068 m68*-altos-*
23 ARM RISCix arm-*-* (as host)
26 * New features for SVR4
28 On SVR4 native platforms (such as Solaris), if you attach to a process
29 without first loading a symbol file, GDB will now attempt to locate and
30 load symbols from the running process's executable file.
32 * Many C++ enhancements
34 C++ support has been greatly improved. Overload resolution now works properly
35 in almost all cases. RTTI support is on the way.
37 * Remote targets can connect to a sub-program
39 A popen(3) style serial-device has been added. This device starts a
40 sub-process (such as a stand-alone simulator) and then communicates
41 with that. The sub-program to run is specified using the syntax
42 ``|<program> <args>'' vis:
44 (gdb) set remotedebug 1
45 (gdb) target extended-remote |mn10300-elf-sim program-args
47 * MIPS 64 remote protocol
49 A long standing bug in the mips64 remote protocol where by GDB
50 expected certain 32 bit registers (ex SR) to be transfered as 32
51 instead of 64 bits has been fixed.
53 The command ``set remote-mips64-transfers-32bit-regs on'' has been
54 added to provide backward compatibility with older versions of GDB.
56 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
58 The command ``set remotebinarydownload'' command has been replaced by
59 ``set remote X-packet''. Other commands in ``set remote'' family
60 include ``set remote P-packet''.
62 * Breakpoint commands accept ranges.
64 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
65 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
66 ``tracepoint passcount'' also accepts a range of tracepoints.
68 * ``apropos'' command added.
70 The ``apropos'' command searches through command names and
71 documentation strings, printing out matches, making it much easier to
72 try to find a command that does what you are looking for.
76 A new machine oriented interface (MI) has been added to GDB. This
77 interface is designed for debug environments running GDB as a separate
78 process. This is part of the long term libGDB project. See
79 gdb/mi/gdbmi.texinfo for further information. It can be enabled by
82 .../configure --enable-gdbmi
84 *** Changes in GDB-4.18:
86 * New native configurations
88 HP-UX 10.20 hppa*-*-hpux10.20
89 HP-UX 11.x hppa*-*-hpux11.0*
90 M68K Linux m68*-*-linux*
94 Fujitsu FR30 fr30-*-elf*
95 Intel StrongARM strongarm-*-*
96 Mitsubishi D30V d30v-*-*
98 * OBSOLETE configurations
100 Gould PowerNode, NP1 np1-*-*, pn-*-*
102 Configurations that have been declared obsolete will be commented out,
103 but the code will be left in place. If there is no activity to revive
104 these configurations before the next release of GDB, the sources will
105 be permanently REMOVED.
109 As a compatibility experiment, GDB's source files buildsym.h and
110 buildsym.c have been converted to pure standard C, no longer
111 containing any K&R compatibility code. We believe that all systems in
112 use today either come with a standard C compiler, or have a GCC port
113 available. If this is not true, please report the affected
114 configuration to bug-gdb@gnu.org immediately. See the README file for
115 information about getting a standard C compiler if you don't have one
120 GDB now uses readline 2.2.
122 * set extension-language
124 You can now control the mapping between filename extensions and source
125 languages by using the `set extension-language' command. For instance,
126 you can ask GDB to treat .c files as C++ by saying
127 set extension-language .c c++
128 The command `info extensions' lists all of the recognized extensions
129 and their associated languages.
131 * Setting processor type for PowerPC and RS/6000
133 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
134 you can use the `set processor' command to specify what variant of the
135 PowerPC family you are debugging. The command
139 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
140 following PowerPC and RS6000 variants:
142 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
143 rs6000 IBM RS6000 ("POWER") architecture, user-level view
145 403GC IBM PowerPC 403GC
146 505 Motorola PowerPC 505
147 860 Motorola PowerPC 860 or 850
148 601 Motorola PowerPC 601
149 602 Motorola PowerPC 602
150 603 Motorola/IBM PowerPC 603 or 603e
151 604 Motorola PowerPC 604 or 604e
152 750 Motorola/IBM PowerPC 750 or 750
154 At the moment, this command just tells GDB what to name the
155 special-purpose processor registers. Since almost all the affected
156 registers are inaccessible to user-level programs, this command is
157 only useful for remote debugging in its present form.
161 Thanks to a major code donation from Hewlett-Packard, GDB now has much
162 more extensive support for HP-UX. Added features include shared
163 library support, kernel threads and hardware watchpoints for 11.00,
164 support for HP's ANSI C and C++ compilers, and a compatibility mode
165 for xdb and dbx commands.
169 HP's donation includes the new concept of catchpoints, which is a
170 generalization of the old catch command. On HP-UX, it is now possible
171 to catch exec, fork, and vfork, as well as library loading.
173 This means that the existing catch command has changed; its first
174 argument now specifies the type of catch to be set up. See the
175 output of "help catch" for a list of catchpoint types.
177 * Debugging across forks
179 On HP-UX, you can choose which process to debug when a fork() happens
184 HP has donated a curses-based terminal user interface (TUI). To get
185 it, build with --enable-tui. Although this can be enabled for any
186 configuration, at present it only works for native HP debugging.
188 * GDB remote protocol additions
190 A new protocol packet 'X' that writes binary data is now available.
191 Default behavior is to try 'X', then drop back to 'M' if the stub
192 fails to respond. The settable variable `remotebinarydownload'
193 allows explicit control over the use of 'X'.
195 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
196 full 64-bit address. The command
198 set remoteaddresssize 32
200 can be used to revert to the old behaviour. For existing remote stubs
201 the change should not be noticed, as the additional address information
204 In order to assist in debugging stubs, you may use the maintenance
205 command `packet' to send any text string to the stub. For instance,
207 maint packet heythere
209 sends the packet "$heythere#<checksum>". Note that it is very easy to
210 disrupt a debugging session by sending the wrong packet at the wrong
213 The compare-sections command allows you to compare section data on the
214 target to what is in the executable file without uploading or
215 downloading, by comparing CRC checksums.
217 * Tracing can collect general expressions
219 You may now collect general expressions at tracepoints. This requires
220 further additions to the target-side stub; see tracepoint.c and
221 doc/agentexpr.texi for further details.
223 * mask-address variable for Mips
225 For Mips targets, you may control the zeroing of the upper 32 bits of
226 a 64-bit address by entering `set mask-address on'. This is mainly
227 of interest to users of embedded R4xxx and R5xxx processors.
229 * Higher serial baud rates
231 GDB's serial code now allows you to specify baud rates 57600, 115200,
232 230400, and 460800 baud. (Note that your host system may not be able
233 to achieve all of these rates.)
237 The i960 configuration now includes an initial implementation of a
238 builtin simulator, contributed by Jim Wilson.
241 *** Changes in GDB-4.17:
243 * New native configurations
245 Alpha GNU/Linux alpha*-*-linux*
246 Unixware 2.x i[3456]86-unixware2*
247 Irix 6.x mips*-sgi-irix6*
248 PowerPC GNU/Linux powerpc-*-linux*
249 PowerPC Solaris powerpcle-*-solaris*
250 Sparc GNU/Linux sparc-*-linux*
251 Motorola sysV68 R3V7.1 m68k-motorola-sysv
255 Argonaut Risc Chip (ARC) arc-*-*
256 Hitachi H8/300S h8300*-*-*
257 Matsushita MN10200 w/simulator mn10200-*-*
258 Matsushita MN10300 w/simulator mn10300-*-*
259 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
260 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
261 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
262 Mitsubishi D10V w/simulator d10v-*-*
263 Mitsubishi M32R/D w/simulator m32r-*-elf*
264 Tsqware Sparclet sparclet-*-*
265 NEC V850 w/simulator v850-*-*
267 * New debugging protocols
269 ARM with RDI protocol arm*-*-*
270 M68K with dBUG monitor m68*-*-{aout,coff,elf}
271 DDB and LSI variants of PMON protocol mips*-*-*
272 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
273 PowerPC with SDS protocol powerpc{,le}-*-eabi
274 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
278 All configurations can now understand and use the DWARF 2 debugging
279 format. The choice is automatic, if the symbol file contains DWARF 2
284 GDB now includes basic Java language support. This support is
285 only useful with Java compilers that produce native machine code.
287 * solib-absolute-prefix and solib-search-path
289 For SunOS and SVR4 shared libraries, you may now set the prefix for
290 loading absolute shared library symbol files, and the search path for
291 locating non-absolute shared library symbol files.
293 * Live range splitting
295 GDB can now effectively debug code for which GCC has performed live
296 range splitting as part of its optimization. See gdb/doc/LRS for
297 more details on the expected format of the stabs information.
301 GDB's support for the GNU Hurd, including thread debugging, has been
302 updated to work with current versions of the Hurd.
306 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
307 instruction set. ARM GDB automatically detects when Thumb
308 instructions are in use, and adjusts disassembly and backtracing
313 GDB's MIPS target configurations now handle the MIP16 16-bit
318 GDB now includes support for overlays; if an executable has been
319 linked such that multiple sections are based at the same address, GDB
320 will decide which section to use for symbolic info. You can choose to
321 control the decision manually, using overlay commands, or implement
322 additional target-side support and use "overlay load-target" to bring
323 in the overlay mapping. Do "help overlay" for more detail.
327 The command "info symbol <address>" displays information about
328 the symbol at the specified address.
332 The standard remote protocol now includes an extension that allows
333 asynchronous collection and display of trace data. This requires
334 extensive support in the target-side debugging stub. Tracing mode
335 includes a new interaction mode in GDB and new commands: see the
336 file tracepoint.c for more details.
340 Configurations for embedded MIPS now include a simulator contributed
341 by Cygnus Solutions. The simulator supports the instruction sets
342 of most MIPS variants.
346 Sparc configurations may now include the ERC32 simulator contributed
347 by the European Space Agency. The simulator is not built into
348 Sparc targets by default; configure with --enable-sim to include it.
352 For target configurations that may include multiple variants of a
353 basic architecture (such as MIPS and SH), you may now set the
354 architecture explicitly. "set arch" sets, "info arch" lists
355 the possible architectures.
357 *** Changes in GDB-4.16:
359 * New native configurations
361 Windows 95, x86 Windows NT i[345]86-*-cygwin32
362 M68K NetBSD m68k-*-netbsd*
363 PowerPC AIX 4.x powerpc-*-aix*
364 PowerPC MacOS powerpc-*-macos*
365 PowerPC Windows NT powerpcle-*-cygwin32
366 RS/6000 AIX 4.x rs6000-*-aix4*
370 ARM with RDP protocol arm-*-*
371 I960 with MON960 i960-*-coff
372 MIPS VxWorks mips*-*-vxworks*
373 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
374 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
376 Matra Sparclet sparclet-*-*
380 The powerpc-eabi configuration now includes the PSIM simulator,
381 contributed by Andrew Cagney, with assistance from Mike Meissner.
382 PSIM is a very elaborate model of the PowerPC, including not only
383 basic instruction set execution, but also details of execution unit
384 performance and I/O hardware. See sim/ppc/README for more details.
388 GDB now works with Solaris 2.5.
390 * Windows 95/NT native
392 GDB will now work as a native debugger on Windows 95 and Windows NT.
393 To build it from source, you must use the "gnu-win32" environment,
394 which uses a DLL to emulate enough of Unix to run the GNU tools.
395 Further information, binaries, and sources are available at
396 ftp.cygnus.com, under pub/gnu-win32.
398 * dont-repeat command
400 If a user-defined command includes the command `dont-repeat', then the
401 command will not be repeated if the user just types return. This is
402 useful if the command is time-consuming to run, so that accidental
403 extra keystrokes don't run the same command many times.
405 * Send break instead of ^C
407 The standard remote protocol now includes an option to send a break
408 rather than a ^C to the target in order to interrupt it. By default,
409 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
411 * Remote protocol timeout
413 The standard remote protocol includes a new variable `remotetimeout'
414 that allows you to set the number of seconds before GDB gives up trying
415 to read from the target. The default value is 2.
417 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
419 By default GDB will automatically keep track of objects as they are
420 loaded and unloaded by the dynamic linker. By using the command `set
421 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
422 when shared library events occur, thus allowing you to set breakpoints
423 in shared libraries which are explicitly loaded by the inferior.
425 Note this feature does not work on hpux8. On hpux9 you must link
426 /usr/lib/end.o into your program. This feature should work
427 automatically on hpux10.
429 * Irix 5.x hardware watchpoint support
431 Irix 5 configurations now support the use of hardware watchpoints.
433 * Mips protocol "SYN garbage limit"
435 When debugging a Mips target using the `target mips' protocol, you
436 may set the number of characters that GDB will ignore by setting
437 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
438 every character. The default value is 1050.
440 * Recording and replaying remote debug sessions
442 If you set `remotelogfile' to the name of a file, gdb will write to it
443 a recording of a remote debug session. This recording may then be
444 replayed back to gdb using "gdbreplay". See gdbserver/README for
445 details. This is useful when you have a problem with GDB while doing
446 remote debugging; you can make a recording of the session and send it
447 to someone else, who can then recreate the problem.
449 * Speedups for remote debugging
451 GDB includes speedups for downloading and stepping MIPS systems using
452 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
453 and more efficient S-record downloading.
455 * Memory use reductions and statistics collection
457 GDB now uses less memory and reports statistics about memory usage.
458 Try the `maint print statistics' command, for example.
460 *** Changes in GDB-4.15:
464 The symbol reader for AIX GDB now uses partial symbol tables. This
465 can greatly improve startup time, especially for large executables.
467 * Remote targets use caching
469 Remote targets now use a data cache to speed up communication with the
470 remote side. The data cache could lead to incorrect results because
471 it doesn't know about volatile variables, thus making it impossible to
472 debug targets which use memory mapped I/O devices. `set remotecache
473 off' turns the the data cache off.
475 * Remote targets may have threads
477 The standard remote protocol now includes support for multiple threads
478 in the target system, using new protocol commands 'H' and 'T'. See
479 gdb/remote.c for details.
483 If GDB is configured with `--enable-netrom', then it will include
484 support for the NetROM ROM emulator from XLNT Designs. The NetROM
485 acts as though it is a bank of ROM on the target board, but you can
486 write into it over the network. GDB's support consists only of
487 support for fast loading into the emulated ROM; to debug, you must use
488 another protocol, such as standard remote protocol. The usual
489 sequence is something like
491 target nrom <netrom-hostname>
493 target remote <netrom-hostname>:1235
497 GDB now includes support for the Apple Macintosh, as a host only. It
498 may be run as either an MPW tool or as a standalone application, and
499 it can debug through the serial port. All the usual GDB commands are
500 available, but to the target command, you must supply "serial" as the
501 device type instead of "/dev/ttyXX". See mpw-README in the main
502 directory for more information on how to build. The MPW configuration
503 scripts */mpw-config.in support only a few targets, and only the
504 mips-idt-ecoff target has been tested.
508 GDB configuration now uses autoconf. This is not user-visible,
509 but does simplify configuration and building.
513 GDB now supports hpux10.
515 *** Changes in GDB-4.14:
517 * New native configurations
519 x86 FreeBSD i[345]86-*-freebsd
520 x86 NetBSD i[345]86-*-netbsd
521 NS32k NetBSD ns32k-*-netbsd
522 Sparc NetBSD sparc-*-netbsd
526 A29K VxWorks a29k-*-vxworks
527 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
528 CPU32 EST-300 emulator m68*-*-est*
529 PowerPC ELF powerpc-*-elf
532 * Alpha OSF/1 support for procfs
534 GDB now supports procfs under OSF/1-2.x and higher, which makes it
535 possible to attach to running processes. As the mounting of the /proc
536 filesystem is optional on the Alpha, GDB automatically determines
537 the availability of /proc during startup. This can lead to problems
538 if /proc is unmounted after GDB has been started.
540 * Arguments to user-defined commands
542 User commands may accept up to 10 arguments separated by whitespace.
543 Arguments are accessed within the user command via $arg0..$arg9. A
546 print $arg0 + $arg1 + $arg2
548 To execute the command use:
551 Defines the command "adder" which prints the sum of its three arguments.
552 Note the arguments are text substitutions, so they may reference variables,
553 use complex expressions, or even perform inferior function calls.
555 * New `if' and `while' commands
557 This makes it possible to write more sophisticated user-defined
558 commands. Both commands take a single argument, which is the
559 expression to evaluate, and must be followed by the commands to
560 execute, one per line, if the expression is nonzero, the list being
561 terminated by the word `end'. The `if' command list may include an
562 `else' word, which causes the following commands to be executed only
563 if the expression is zero.
565 * Fortran source language mode
567 GDB now includes partial support for Fortran 77. It will recognize
568 Fortran programs and can evaluate a subset of Fortran expressions, but
569 variables and functions may not be handled correctly. GDB will work
570 with G77, but does not yet know much about symbols emitted by other
573 * Better HPUX support
575 Most debugging facilities now work on dynamic executables for HPPAs
576 running hpux9 or later. You can attach to running dynamically linked
577 processes, but by default the dynamic libraries will be read-only, so
578 for instance you won't be able to put breakpoints in them. To change
579 that behavior do the following before running the program:
585 This will cause the libraries to be mapped private and read-write.
586 To revert to the normal behavior, do this:
592 You cannot set breakpoints or examine data in the library until after
593 the library is loaded if the function/data symbols do not have
596 GDB can now also read debug symbols produced by the HP C compiler on
597 HPPAs (sorry, no C++, Fortran or 68k support).
599 * Target byte order now dynamically selectable
601 You can choose which byte order to use with a target system, via the
602 commands "set endian big" and "set endian little", and you can see the
603 current setting by using "show endian". You can also give the command
604 "set endian auto", in which case GDB will use the byte order
605 associated with the executable. Currently, only embedded MIPS
606 configurations support dynamic selection of target byte order.
608 * New DOS host serial code
610 This version uses DPMI interrupts to handle buffered I/O, so you
611 no longer need to run asynctsr when debugging boards connected to
614 *** Changes in GDB-4.13:
616 * New "complete" command
618 This lists all the possible completions for the rest of the line, if it
619 were to be given as a command itself. This is intended for use by emacs.
621 * Trailing space optional in prompt
623 "set prompt" no longer adds a space for you after the prompt you set. This
624 allows you to set a prompt which ends in a space or one that does not.
626 * Breakpoint hit counts
628 "info break" now displays a count of the number of times the breakpoint
629 has been hit. This is especially useful in conjunction with "ignore"; you
630 can ignore a large number of breakpoint hits, look at the breakpoint info
631 to see how many times the breakpoint was hit, then run again, ignoring one
632 less than that number, and this will get you quickly to the last hit of
635 * Ability to stop printing at NULL character
637 "set print null-stop" will cause GDB to stop printing the characters of
638 an array when the first NULL is encountered. This is useful when large
639 arrays actually contain only short strings.
641 * Shared library breakpoints
643 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
644 breakpoints in shared libraries before the executable is run.
646 * Hardware watchpoints
648 There is a new hardware breakpoint for the watch command for sparclite
649 targets. See gdb/sparclite/hw_breakpoint.note.
651 Hardware watchpoints are also now supported under Linux.
655 Annotations have been added. These are for use with graphical interfaces,
656 and are still experimental. Currently only gdba.el uses these.
658 * Improved Irix 5 support
660 GDB now works properly with Irix 5.2.
662 * Improved HPPA support
664 GDB now works properly with the latest GCC and GAS.
666 * New native configurations
668 Sequent PTX4 i[34]86-sequent-ptx4
669 HPPA running OSF/1 hppa*-*-osf*
670 Atari TT running SVR4 m68*-*-sysv4*
671 RS/6000 LynxOS rs6000-*-lynxos*
675 OS/9000 i[34]86-*-os9k
676 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
679 * Hitachi SH7000 and E7000-PC ICE support
681 There is now support for communicating with the Hitachi E7000-PC ICE.
682 This is available automatically when GDB is configured for the SH.
686 As usual, a variety of small fixes and improvements, both generic
687 and configuration-specific. See the ChangeLog for more detail.
689 *** Changes in GDB-4.12:
691 * Irix 5 is now supported
695 GDB-4.12 on the HPPA has a number of changes which make it unable
696 to debug the output from the currently released versions of GCC and
697 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
698 of GCC and GAS, versions of these tools designed to work with GDB-4.12
699 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
702 *** Changes in GDB-4.11:
704 * User visible changes:
708 The "set remotedebug" option is now consistent between the mips remote
709 target, remote targets using the gdb-specific protocol, UDI (AMD's
710 debug protocol for the 29k) and the 88k bug monitor. It is now an
711 integer specifying a debug level (normally 0 or 1, but 2 means more
712 debugging info for the mips target).
714 * DEC Alpha native support
716 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
717 debug info, but GDB works fairly well with the DEC compiler and should
718 work with a future GCC release. See the README file for a few
719 Alpha-specific notes.
721 * Preliminary thread implementation
723 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
725 * LynxOS native and target support for 386
727 This release has been hosted on LynxOS 2.2, and also can be configured
728 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
731 * Improvements in C++ mangling/demangling.
733 This release has much better g++ debugging, specifically in name
734 mangling/demangling, virtual function calls, print virtual table,
735 call methods, ...etc.
737 *** Changes in GDB-4.10:
739 * User visible changes:
741 Remote debugging using the GDB-specific (`target remote') protocol now
742 supports the `load' command. This is only useful if you have some
743 other way of getting the stub to the target system, and you can put it
744 somewhere in memory where it won't get clobbered by the download.
746 Filename completion now works.
748 When run under emacs mode, the "info line" command now causes the
749 arrow to point to the line specified. Also, "info line" prints
750 addresses in symbolic form (as well as hex).
752 All vxworks based targets now support a user settable option, called
753 vxworks-timeout. This option represents the number of seconds gdb
754 should wait for responses to rpc's. You might want to use this if
755 your vxworks target is, perhaps, a slow software simulator or happens
756 to be on the far side of a thin network line.
760 This release contains support for using a DEC alpha as a GDB host for
761 cross debugging. Native alpha debugging is not supported yet.
764 *** Changes in GDB-4.9:
768 This is the first GDB release which is accompanied by a matching testsuite.
769 The testsuite requires installation of dejagnu, which should be available
770 via ftp from most sites that carry GNU software.
774 'Cfront' style demangling has had its name changed to 'ARM' style, to
775 emphasize that it was written from the specifications in the C++ Annotated
776 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
777 disclaimers, it still generated too much confusion with users attempting to
778 use gdb with AT&T cfront.
782 GDB now uses a standard remote interface to a simulator library.
783 So far, the library contains simulators for the Zilog Z8001/2, the
784 Hitachi H8/300, H8/500 and Super-H.
786 * New targets supported
788 H8/300 simulator h8300-hitachi-hms or h8300hms
789 H8/500 simulator h8500-hitachi-hms or h8500hms
790 SH simulator sh-hitachi-hms or sh
791 Z8000 simulator z8k-zilog-none or z8ksim
792 IDT MIPS board over serial line mips-idt-ecoff
794 Cross-debugging to GO32 targets is supported. It requires a custom
795 version of the i386-stub.c module which is integrated with the
796 GO32 memory extender.
798 * New remote protocols
800 MIPS remote debugging protocol.
802 * New source languages supported
804 This version includes preliminary support for Chill, a Pascal like language
805 used by telecommunications companies. Chill support is also being integrated
806 into the GNU compiler, but we don't know when it will be publically available.
809 *** Changes in GDB-4.8:
811 * HP Precision Architecture supported
813 GDB now supports HP PA-RISC machines running HPUX. A preliminary
814 version of this support was available as a set of patches from the
815 University of Utah. GDB does not support debugging of programs
816 compiled with the HP compiler, because HP will not document their file
817 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
818 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
820 Many problems in the preliminary version have been fixed.
822 * Faster and better demangling
824 We have improved template demangling and fixed numerous bugs in the GNU style
825 demangler. It can now handle type modifiers such as `static' or `const'. Wide
826 character types (wchar_t) are now supported. Demangling of each symbol is now
827 only done once, and is cached when the symbol table for a file is read in.
828 This results in a small increase in memory usage for C programs, a moderate
829 increase in memory usage for C++ programs, and a fantastic speedup in
832 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
833 from the specifications in the Annotated Reference Manual, which AT&T's
834 compiler does not actually implement.
836 * G++ multiple inheritance compiler problem
838 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
839 inheritance lattices was reworked to properly discover ambiguities. We
840 recently found an example which causes this new algorithm to fail in a
841 very subtle way, producing bad debug information for those classes.
842 The file 'gcc.patch' (in this directory) can be applied to gcc to
843 circumvent the problem. A future GCC release will contain a complete
846 The previous G++ debug info problem (mentioned below for the gdb-4.7
847 release) is fixed in gcc version 2.3.2.
849 * Improved configure script
851 The `configure' script will now attempt to guess your system type if
852 you don't supply a host system type. The old scheme of supplying a
853 host system triplet is preferable over using this. All the magic is
854 done in the new `config.guess' script. Examine it for details.
856 We have also brought our configure script much more in line with the FSF's
857 version. It now supports the --with-xxx options. In particular,
858 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
859 The resulting GDB will not be able to read arbitrary object file formats --
860 only the format ``expected'' to be used on the configured target system.
861 We hope to make this the default in a future release.
863 * Documentation improvements
865 There's new internal documentation on how to modify GDB, and how to
866 produce clean changes to the code. We implore people to read it
867 before submitting changes.
869 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
870 M4 macros. The new texinfo.tex is provided in this release. Pre-built
871 `info' files are also provided. To build `info' files from scratch,
872 you will need the latest `makeinfo' release, which will be available in
873 a future texinfo-X.Y release.
875 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
876 We're not sure exactly which versions have this problem, but it has
877 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
878 or better. If that isn't possible, there is a patch in
879 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
884 GDB now supports array constants that can be used in expressions typed in by
885 the user. The syntax is `{element, element, ...}'. Ie: you can now type
886 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
889 The new directory `gdb/sparclite' contains a program that demonstrates
890 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
892 * New native hosts supported
894 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
895 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
897 * New targets supported
899 AMD 29k family via UDI a29k-amd-udi or udi29k
901 * New file formats supported
903 BFD now supports reading HP/PA-RISC executables (SOM file format?),
904 HPUX core files, and SCO 3.2v2 core files.
908 Attaching to processes now works again; thanks for the many bug reports.
910 We have also stomped on a bunch of core dumps caused by
911 printf_filtered("%s") problems.
913 We eliminated a copyright problem on the rpc and ptrace header files
914 for VxWorks, which was discovered at the last minute during the 4.7
915 release. You should now be able to build a VxWorks GDB.
917 You can now interrupt gdb while an attached process is running. This
918 will cause the attached process to stop, and give control back to GDB.
920 We fixed problems caused by using too many file descriptors
921 for reading symbols from object files and libraries. This was
922 especially a problem for programs that used many (~100) shared
925 The `step' command now only enters a subroutine if there is line number
926 information for the subroutine. Otherwise it acts like the `next'
927 command. Previously, `step' would enter subroutines if there was
928 any debugging information about the routine. This avoids problems
929 when using `cc -g1' on MIPS machines.
931 * Internal improvements
933 GDB's internal interfaces have been improved to make it easier to support
934 debugging of multiple languages in the future.
936 GDB now uses a common structure for symbol information internally.
937 Minimal symbols (derived from linkage symbols in object files), partial
938 symbols (from a quick scan of debug information), and full symbols
939 contain a common subset of information, making it easier to write
940 shared code that handles any of them.
942 * New command line options
944 We now accept --silent as an alias for --quiet.
948 The memory-mapped-malloc library is now licensed under the GNU Library
949 General Public License.
951 *** Changes in GDB-4.7:
953 * Host/native/target split
955 GDB has had some major internal surgery to untangle the support for
956 hosts and remote targets. Now, when you configure GDB for a remote
957 target, it will no longer load in all of the support for debugging
958 local programs on the host. When fully completed and tested, this will
959 ensure that arbitrary host/target combinations are possible.
961 The primary conceptual shift is to separate the non-portable code in
962 GDB into three categories. Host specific code is required any time GDB
963 is compiled on that host, regardless of the target. Target specific
964 code relates to the peculiarities of the target, but can be compiled on
965 any host. Native specific code is everything else: it can only be
966 built when the host and target are the same system. Child process
967 handling and core file support are two common `native' examples.
969 GDB's use of /proc for controlling Unix child processes is now cleaner.
970 It has been split out into a single module under the `target_ops' vector,
971 plus two native-dependent functions for each system that uses /proc.
973 * New hosts supported
975 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
976 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
977 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
979 * New targets supported
981 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
982 68030 and CPU32 m68030-*-*, m68332-*-*
984 * New native hosts supported
986 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
987 (386bsd is not well tested yet)
988 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
990 * New file formats supported
992 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
993 supports reading of `a.out.adobe' object files, which are an a.out
994 format extended with minimal information about multiple sections.
998 `show copying' is the same as the old `info copying'.
999 `show warranty' is the same as `info warrantee'.
1000 These were renamed for consistency. The old commands continue to work.
1002 `info handle' is a new alias for `info signals'.
1004 You can now define pre-command hooks, which attach arbitrary command
1005 scripts to any command. The commands in the hook will be executed
1006 prior to the user's command. You can also create a hook which will be
1007 executed whenever the program stops. See gdb.texinfo.
1011 We now deal with Cfront style name mangling, and can even extract type
1012 info from mangled symbols. GDB can automatically figure out which
1013 symbol mangling style your C++ compiler uses.
1015 Calling of methods and virtual functions has been improved as well.
1019 The crash that occured when debugging Sun Ansi-C compiled binaries is
1020 fixed. This was due to mishandling of the extra N_SO stabs output
1023 We also finally got Ultrix 4.2 running in house, and fixed core file
1024 support, with help from a dozen people on the net.
1026 John M. Farrell discovered that the reason that single-stepping was so
1027 slow on all of the Mips based platforms (primarily SGI and DEC) was
1028 that we were trying to demangle and lookup a symbol used for internal
1029 purposes on every instruction that was being stepped through. Changing
1030 the name of that symbol so that it couldn't be mistaken for a C++
1031 mangled symbol sped things up a great deal.
1033 Rich Pixley sped up symbol lookups in general by getting much smarter
1034 about when C++ symbol mangling is necessary. This should make symbol
1035 completion (TAB on the command line) much faster. It's not as fast as
1036 we'd like, but it's significantly faster than gdb-4.6.
1040 A new user controllable variable 'call_scratch_address' can
1041 specify the location of a scratch area to be used when GDB
1042 calls a function in the target. This is necessary because the
1043 usual method of putting the scratch area on the stack does not work
1044 in systems that have separate instruction and data spaces.
1046 We integrated changes to support the 29k UDI (Universal Debugger
1047 Interface), but discovered at the last minute that we didn't have all
1048 of the appropriate copyright paperwork. We are working with AMD to
1049 resolve this, and hope to have it available soon.
1053 We have sped up the remote serial line protocol, especially for targets
1054 with lots of registers. It now supports a new `expedited status' ('T')
1055 message which can be used in place of the existing 'S' status message.
1056 This allows the remote stub to send only the registers that GDB
1057 needs to make a quick decision about single-stepping or conditional
1058 breakpoints, eliminating the need to fetch the entire register set for
1059 each instruction being stepped through.
1061 The GDB remote serial protocol now implements a write-through cache for
1062 registers, only re-reading the registers if the target has run.
1064 There is also a new remote serial stub for SPARC processors. You can
1065 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1066 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1067 processor with a serial port.
1071 Configure.in files have become much easier to read and modify. A new
1072 `table driven' format makes it more obvious what configurations are
1073 supported, and what files each one uses.
1077 There is a new opcodes library which will eventually contain all of the
1078 disassembly routines and opcode tables. At present, it only contains
1079 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1080 disassembler (binutils/objdump) to share these routines.
1082 The libiberty library is now copylefted under the GNU Library General
1083 Public License. This allows more liberal use, and was done so libg++
1084 can use it. This makes no difference to GDB, since the Library License
1085 grants all the rights from the General Public License.
1089 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1090 reference to the stabs symbol info used by the debugger. It is (as far
1091 as we know) the only published document on this fascinating topic. We
1092 encourage you to read it, compare it to the stabs information on your
1093 system, and send improvements on the document in general (to
1094 bug-gdb@prep.ai.mit.edu).
1096 And, of course, many bugs have been fixed.
1099 *** Changes in GDB-4.6:
1101 * Better support for C++ function names
1103 GDB now accepts as input the "demangled form" of C++ overloaded function
1104 names and member function names, and can do command completion on such names
1105 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1106 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1107 Make use of command completion, it is your friend.
1109 GDB also now accepts a variety of C++ mangled symbol formats. They are
1110 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1111 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1112 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1113 for the list of formats.
1115 * G++ symbol mangling problem
1117 Recent versions of gcc have a bug in how they emit debugging information for
1118 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1119 directory) can be applied to gcc to fix the problem. Alternatively, if you
1120 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1121 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1122 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1125 * New 'maintenance' command
1127 All of the commands related to hacking GDB internals have been moved out of
1128 the main command set, and now live behind the 'maintenance' command. This
1129 can also be abbreviated as 'mt'. The following changes were made:
1131 dump-me -> maintenance dump-me
1132 info all-breakpoints -> maintenance info breakpoints
1133 printmsyms -> maintenance print msyms
1134 printobjfiles -> maintenance print objfiles
1135 printpsyms -> maintenance print psymbols
1136 printsyms -> maintenance print symbols
1138 The following commands are new:
1140 maintenance demangle Call internal GDB demangler routine to
1141 demangle a C++ link name and prints the result.
1142 maintenance print type Print a type chain for a given symbol
1144 * Change to .gdbinit file processing
1146 We now read the $HOME/.gdbinit file before processing the argv arguments
1147 (e.g. reading symbol files or core files). This allows global parameters to
1148 be set, which will apply during the symbol reading. The ./.gdbinit is still
1149 read after argv processing.
1151 * New hosts supported
1153 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1155 Linux support i386-unknown-linux or linux
1157 We are also including code to support the HP/PA running BSD and HPUX. This
1158 is almost guaranteed not to work, as we didn't have time to test or build it
1159 for this release. We are including it so that the more adventurous (or
1160 masochistic) of you can play with it. We also had major problems with the
1161 fact that the compiler that we got from HP doesn't support the -g option.
1164 * New targets supported
1166 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1168 * More smarts about finding #include files
1170 GDB now remembers the compilation directory for all include files, and for
1171 all files from which C is generated (like yacc and lex sources). This
1172 greatly improves GDB's ability to find yacc/lex sources, and include files,
1173 especially if you are debugging your program from a directory different from
1174 the one that contains your sources.
1176 We also fixed a bug which caused difficulty with listing and setting
1177 breakpoints in include files which contain C code. (In the past, you had to
1178 try twice in order to list an include file that you hadn't looked at before.)
1180 * Interesting infernals change
1182 GDB now deals with arbitrary numbers of sections, where the symbols for each
1183 section must be relocated relative to that section's landing place in the
1184 target's address space. This work was needed to support ELF with embedded
1185 stabs used by Solaris-2.0.
1187 * Bug fixes (of course!)
1189 There have been loads of fixes for the following things:
1190 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1191 i960, stabs, DOS(GO32), procfs, etc...
1193 See the ChangeLog for details.
1195 *** Changes in GDB-4.5:
1197 * New machines supported (host and target)
1199 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1201 SGI Irix-4.x mips-sgi-irix4 or iris4
1203 * New malloc package
1205 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1206 Mmalloc is capable of handling mutiple heaps of memory. It is also
1207 capable of saving a heap to a file, and then mapping it back in later.
1208 This can be used to greatly speedup the startup of GDB by using a
1209 pre-parsed symbol table which lives in a mmalloc managed heap. For
1210 more details, please read mmalloc/mmalloc.texi.
1214 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1215 'help info proc' for details.
1217 * MIPS ecoff symbol table format
1219 The code that reads MIPS symbol table format is now supported on all hosts.
1220 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1223 * File name changes for MS-DOS
1225 Many files in the config directories have been renamed to make it easier to
1226 support GDB on MS-DOSe systems (which have very restrictive file name
1227 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1228 environment) is close to working but has some remaining problems. Note
1229 that debugging of DOS programs is not supported, due to limitations
1230 in the ``operating system'', but it can be used to host cross-debugging.
1232 * Cross byte order fixes
1234 Many fixes have been made to support cross debugging of Sparc and MIPS
1235 targets from hosts whose byte order differs.
1237 * New -mapped and -readnow options
1239 If memory-mapped files are available on your system through the 'mmap'
1240 system call, you can use the -mapped option on the `file' or
1241 `symbol-file' commands to cause GDB to write the symbols from your
1242 program into a reusable file. If the program you are debugging is
1243 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1244 Future GDB debugging sessions will notice the presence of this file,
1245 and will quickly map in symbol information from it, rather than reading
1246 the symbol table from the executable program. Using the '-mapped'
1247 option in a GDB `file' or `symbol-file' command has the same effect as
1248 starting GDB with the '-mapped' command-line option.
1250 You can cause GDB to read the entire symbol table immediately by using
1251 the '-readnow' option with any of the commands that load symbol table
1252 information (or on the GDB command line). This makes the command
1253 slower, but makes future operations faster.
1255 The -mapped and -readnow options are typically combined in order to
1256 build a `fred.syms' file that contains complete symbol information.
1257 A simple GDB invocation to do nothing but build a `.syms' file for future
1260 gdb -batch -nx -mapped -readnow programname
1262 The `.syms' file is specific to the host machine on which GDB is run.
1263 It holds an exact image of GDB's internal symbol table. It cannot be
1264 shared across multiple host platforms.
1266 * longjmp() handling
1268 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1269 siglongjmp() without losing control. This feature has not yet been ported to
1270 all systems. It currently works on many 386 platforms, all MIPS-based
1271 platforms (SGI, DECstation, etc), and Sun3/4.
1275 Preliminary work has been put in to support the new Solaris OS from Sun. At
1276 this time, it can control and debug processes, but it is not capable of
1281 As always, many many bug fixes. The major areas were with g++, and mipsread.
1282 People using the MIPS-based platforms should experience fewer mysterious
1283 crashes and trashed symbol tables.
1285 *** Changes in GDB-4.4:
1287 * New machines supported (host and target)
1289 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1291 BSD Reno on Vax vax-dec-bsd
1292 Ultrix on Vax vax-dec-ultrix
1294 * New machines supported (target)
1296 AMD 29000 embedded, using EBMON a29k-none-none
1300 GDB continues to improve its handling of C++. `References' work better.
1301 The demangler has also been improved, and now deals with symbols mangled as
1302 per the Annotated C++ Reference Guide.
1304 GDB also now handles `stabs' symbol information embedded in MIPS
1305 `ecoff' symbol tables. Since the ecoff format was not easily
1306 extensible to handle new languages such as C++, this appeared to be a
1307 good way to put C++ debugging info into MIPS binaries. This option
1308 will be supported in the GNU C compiler, version 2, when it is
1311 * New features for SVR4
1313 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1314 shared libraries. Debugging dynamically linked programs should present
1315 only minor differences from debugging statically linked programs.
1317 The `info proc' command will print out information about any process
1318 on an SVR4 system (including the one you are debugging). At the moment,
1319 it prints the address mappings of the process.
1321 If you bring up GDB on another SVR4 system, please send mail to
1322 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1324 * Better dynamic linking support in SunOS
1326 Reading symbols from shared libraries which contain debugging symbols
1327 now works properly. However, there remain issues such as automatic
1328 skipping of `transfer vector' code during function calls, which
1329 make it harder to debug code in a shared library, than to debug the
1330 same code linked statically.
1334 GDB is now using the latest `getopt' routines from the FSF. This
1335 version accepts the -- prefix for options with long names. GDB will
1336 continue to accept the old forms (-option and +option) as well.
1337 Various single letter abbreviations for options have been explicity
1338 added to the option table so that they won't get overshadowed in the
1339 future by other options that begin with the same letter.
1343 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1344 Many assorted bugs have been handled. Many more remain to be handled.
1345 See the various ChangeLog files (primarily in gdb and bfd) for details.
1348 *** Changes in GDB-4.3:
1350 * New machines supported (host and target)
1352 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1353 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1354 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1356 * Almost SCO Unix support
1358 We had hoped to support:
1359 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1360 (except for core file support), but we discovered very late in the release
1361 that it has problems with process groups that render gdb unusable. Sorry
1362 about that. I encourage people to fix it and post the fixes.
1364 * Preliminary ELF and DWARF support
1366 GDB can read ELF object files on System V Release 4, and can handle
1367 debugging records for C, in DWARF format, in ELF files. This support
1368 is preliminary. If you bring up GDB on another SVR4 system, please
1369 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1374 GDB now uses the latest `readline' library. One user-visible change
1375 is that two tabs will list possible command completions, which previously
1376 required typing M-? (meta-question mark, or ESC ?).
1380 The `stepi' bug that many of you noticed has been squashed.
1381 Many bugs in C++ have been handled. Many more remain to be handled.
1382 See the various ChangeLog files (primarily in gdb and bfd) for details.
1384 * State of the MIPS world (in case you wondered):
1386 GDB can understand the symbol tables emitted by the compilers
1387 supplied by most vendors of MIPS-based machines, including DEC. These
1388 symbol tables are in a format that essentially nobody else uses.
1390 Some versions of gcc come with an assembler post-processor called
1391 mips-tfile. This program is required if you want to do source-level
1392 debugging of gcc-compiled programs. I believe FSF does not ship
1393 mips-tfile with gcc version 1, but it will eventually come with gcc
1396 Debugging of g++ output remains a problem. g++ version 1.xx does not
1397 really support it at all. (If you're lucky, you should be able to get
1398 line numbers and stack traces to work, but no parameters or local
1399 variables.) With some work it should be possible to improve the
1402 When gcc version 2 is released, you will have somewhat better luck.
1403 However, even then you will get confusing results for inheritance and
1406 We will eventually provide full debugging of g++ output on
1407 DECstations. This will probably involve some kind of stabs-in-ecoff
1408 encapulation, but the details have not been worked out yet.
1411 *** Changes in GDB-4.2:
1413 * Improved configuration
1415 Only one copy of `configure' exists now, and it is not self-modifying.
1416 Porting BFD is simpler.
1420 The `step' and `next' commands now only stop at the first instruction
1421 of a source line. This prevents the multiple stops that used to occur
1422 in switch statements, for-loops, etc. `Step' continues to stop if a
1423 function that has debugging information is called within the line.
1427 Lots of small bugs fixed. More remain.
1429 * New host supported (not target)
1431 Intel 386 PC clone running Mach i386-none-mach
1434 *** Changes in GDB-4.1:
1436 * Multiple source language support
1438 GDB now has internal scaffolding to handle several source languages.
1439 It determines the type of each source file from its filename extension,
1440 and will switch expression parsing and number formatting to match the
1441 language of the function in the currently selected stack frame.
1442 You can also specifically set the language to be used, with
1443 `set language c' or `set language modula-2'.
1447 GDB now has preliminary support for the GNU Modula-2 compiler,
1448 currently under development at the State University of New York at
1449 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1450 continue through the fall of 1991 and into 1992.
1452 Other Modula-2 compilers are currently not supported, and attempting to
1453 debug programs compiled with them will likely result in an error as the
1454 symbol table is read. Feel free to work on it, though!
1456 There are hooks in GDB for strict type checking and range checking,
1457 in the `Modula-2 philosophy', but they do not currently work.
1461 GDB can now write to executable and core files (e.g. patch
1462 a variable's value). You must turn this switch on, specify
1463 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1464 by assigning a new value to a variable. Modifications take
1467 * Automatic SunOS shared library reading
1469 When you run your program, GDB automatically determines where its
1470 shared libraries (if any) have been loaded, and reads their symbols.
1471 The `share' command is no longer needed. This also works when
1472 examining core files.
1476 You can specify the number of lines that the `list' command shows.
1479 * New machines supported (host and target)
1481 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1482 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1483 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1485 * New hosts supported (not targets)
1487 IBM RT/PC: romp-ibm-aix or rtpc
1489 * New targets supported (not hosts)
1491 AMD 29000 embedded with COFF a29k-none-coff
1492 AMD 29000 embedded with a.out a29k-none-aout
1493 Ultracomputer remote kernel debug a29k-nyu-kern
1495 * New remote interfaces
1501 *** Changes in GDB-4.0:
1505 Wide output is wrapped at good places to make the output more readable.
1507 Gdb now supports cross-debugging from a host machine of one type to a
1508 target machine of another type. Communication with the target system
1509 is over serial lines. The ``target'' command handles connecting to the
1510 remote system; the ``load'' command will download a program into the
1511 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1512 also supports debugging of realtime processes running under VxWorks,
1513 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1514 stub on the target system.
1516 New CPUs supported include the AMD 29000 and Intel 960.
1518 GDB now reads object files and symbol tables via a ``binary file''
1519 library, which allows a single copy of GDB to debug programs of multiple
1520 object file types such as a.out and coff.
1522 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1523 refcard.dvi and refcard.ps are available to format it).
1526 * Control-Variable user interface simplified
1528 All variables that control the operation of the debugger can be set
1529 by the ``set'' command, and displayed by the ``show'' command.
1531 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1532 ``Show prompt'' produces the response:
1533 Gdb's prompt is new-gdb=>.
1535 What follows are the NEW set commands. The command ``help set'' will
1536 print a complete list of old and new set commands. ``help set FOO''
1537 will give a longer description of the variable FOO. ``show'' will show
1538 all of the variable descriptions and their current settings.
1540 confirm on/off: Enables warning questions for operations that are
1541 hard to recover from, e.g. rerunning the program while
1542 it is already running. Default is ON.
1544 editing on/off: Enables EMACS style command line editing
1545 of input. Previous lines can be recalled with
1546 control-P, the current line can be edited with control-B,
1547 you can search for commands with control-R, etc.
1550 history filename NAME: NAME is where the gdb command history
1551 will be stored. The default is .gdb_history,
1552 or the value of the environment variable
1555 history size N: The size, in commands, of the command history. The
1556 default is 256, or the value of the environment variable
1559 history save on/off: If this value is set to ON, the history file will
1560 be saved after exiting gdb. If set to OFF, the
1561 file will not be saved. The default is OFF.
1563 history expansion on/off: If this value is set to ON, then csh-like
1564 history expansion will be performed on
1565 command line input. The default is OFF.
1567 radix N: Sets the default radix for input and output. It can be set
1568 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1569 in the current radix, so "set radix 10" is always a no-op.
1571 height N: This integer value is the number of lines on a page. Default
1572 is 24, the current `stty rows'' setting, or the ``li#''
1573 setting from the termcap entry matching the environment
1576 width N: This integer value is the number of characters on a line.
1577 Default is 80, the current `stty cols'' setting, or the ``co#''
1578 setting from the termcap entry matching the environment
1581 Note: ``set screensize'' is obsolete. Use ``set height'' and
1582 ``set width'' instead.
1584 print address on/off: Print memory addresses in various command displays,
1585 such as stack traces and structure values. Gdb looks
1586 more ``symbolic'' if you turn this off; it looks more
1587 ``machine level'' with it on. Default is ON.
1589 print array on/off: Prettyprint arrays. New convenient format! Default
1592 print demangle on/off: Print C++ symbols in "source" form if on,
1595 print asm-demangle on/off: Same, for assembler level printouts
1598 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1601 * Support for Epoch Environment.
1603 The epoch environment is a version of Emacs v18 with windowing. One
1604 new command, ``inspect'', is identical to ``print'', except that if you
1605 are running in the epoch environment, the value is printed in its own
1609 * Support for Shared Libraries
1611 GDB can now debug programs and core files that use SunOS shared libraries.
1612 Symbols from a shared library cannot be referenced
1613 before the shared library has been linked with the program (this
1614 happens after you type ``run'' and before the function main() is entered).
1615 At any time after this linking (including when examining core files
1616 from dynamically linked programs), gdb reads the symbols from each
1617 shared library when you type the ``sharedlibrary'' command.
1618 It can be abbreviated ``share''.
1620 sharedlibrary REGEXP: Load shared object library symbols for files
1621 matching a unix regular expression. No argument
1622 indicates to load symbols for all shared libraries.
1624 info sharedlibrary: Status of loaded shared libraries.
1629 A watchpoint stops execution of a program whenever the value of an
1630 expression changes. Checking for this slows down execution
1631 tremendously whenever you are in the scope of the expression, but is
1632 quite useful for catching tough ``bit-spreader'' or pointer misuse
1633 problems. Some machines such as the 386 have hardware for doing this
1634 more quickly, and future versions of gdb will use this hardware.
1636 watch EXP: Set a watchpoint (breakpoint) for an expression.
1638 info watchpoints: Information about your watchpoints.
1640 delete N: Deletes watchpoint number N (same as breakpoints).
1641 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1642 enable N: Re-enables watchpoint number N (same as breakpoints).
1645 * C++ multiple inheritance
1647 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1650 * C++ exception handling
1652 Gdb now supports limited C++ exception handling. Besides the existing
1653 ability to breakpoint on an exception handler, gdb can breakpoint on
1654 the raising of an exception (before the stack is peeled back to the
1657 catch FOO: If there is a FOO exception handler in the dynamic scope,
1658 set a breakpoint to catch exceptions which may be raised there.
1659 Multiple exceptions (``catch foo bar baz'') may be caught.
1661 info catch: Lists all exceptions which may be caught in the
1662 current stack frame.
1665 * Minor command changes
1667 The command ``call func (arg, arg, ...)'' now acts like the print
1668 command, except it does not print or save a value if the function's result
1669 is void. This is similar to dbx usage.
1671 The ``up'' and ``down'' commands now always print the frame they end up
1672 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1673 frames without printing.
1675 * New directory command
1677 'dir' now adds directories to the FRONT of the source search path.
1678 The path starts off empty. Source files that contain debug information
1679 about the directory in which they were compiled can be found even
1680 with an empty path; Sun CC and GCC include this information. If GDB can't
1681 find your source file in the current directory, type "dir .".
1683 * Configuring GDB for compilation
1685 For normal use, type ``./configure host''. See README or gdb.texinfo
1688 GDB now handles cross debugging. If you are remotely debugging between
1689 two different machines, type ``./configure host -target=targ''.
1690 Host is the machine where GDB will run; targ is the machine
1691 where the program that you are debugging will run.
projects / binutils-gdb.git / blob