1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 5.0:
6 * New native configurations
8 Alpha FreeBSD alpha*-*-freebsd*
9 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
13 * OBSOLETE configurations
15 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
17 * Deleted configurations
21 * All MIPS configurations are multi-arched.
23 Multi-arch support is enabled for all MIPS configurations.
27 GUD support is now a standard part of the EMACS distribution.
29 *** Changes in GDB 5.0:
31 * Improved support for debugging FP programs on x86 targets
33 Unified and much-improved support for debugging floating-point
34 programs on all x86 targets. In particular, ``info float'' now
35 displays the FP registers in the same format on all x86 targets, with
36 greater level of detail.
38 * Improvements and bugfixes in hardware-assisted watchpoints
40 It is now possible to watch array elements, struct members, and
41 bitfields with hardware-assisted watchpoints. Data-read watchpoints
42 on x86 targets no longer erroneously trigger when the address is
45 * Improvements in the native DJGPP version of GDB
47 The distribution now includes all the scripts and auxiliary files
48 necessary to build the native DJGPP version on MS-DOS/MS-Windows
49 machines ``out of the box''.
51 The DJGPP version can now debug programs that use signals. It is
52 possible to catch signals that happened in the debuggee, deliver
53 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
54 would kill the program being debugged.) Programs that hook hardware
55 interrupts (keyboard, timer, etc.) can also be debugged.
57 It is now possible to debug DJGPP programs that redirect their
58 standard handles or switch them to raw (as opposed to cooked) mode, or
59 even close them. The command ``run < foo > bar'' works as expected,
60 and ``info terminal'' reports useful information about the debuggee's
61 terminal, including raw/cooked mode, redirection, etc.
63 The DJGPP version now uses termios functions for console I/O, which
64 enables debugging graphics programs. Interrupting GDB with Ctrl-C
67 DOS-style file names with drive letters are now fully supported by
70 It is now possible to debug DJGPP programs that switch their working
71 directory. It is also possible to rerun the debuggee any number of
72 times without restarting GDB; thus, you can use the same setup,
73 breakpoints, etc. for many debugging sessions.
75 * New native configurations
77 ARM GNU/Linux arm*-*-linux*
78 PowerPC GNU/Linux powerpc-*-linux*
82 Motorola MCore mcore-*-*
83 x86 VxWorks i[3456]86-*-vxworks*
84 PowerPC VxWorks powerpc-*-vxworks*
85 TI TMS320C80 tic80-*-*
87 * OBSOLETE configurations
89 Altos 3068 m68*-altos-*
92 ARM RISCix arm-*-* (as host)
95 Configurations that have been declared obsolete will be commented out,
96 but the code will be left in place. If there is no activity to revive
97 these configurations before the next release of GDB, the sources will
98 be permanently REMOVED.
100 * Gould support removed
102 Support for the Gould PowerNode and NP1 has been removed.
104 * New features for SVR4
106 On SVR4 native platforms (such as Solaris), if you attach to a process
107 without first loading a symbol file, GDB will now attempt to locate and
108 load symbols from the running process's executable file.
110 * Many C++ enhancements
112 C++ support has been greatly improved. Overload resolution now works properly
113 in almost all cases. RTTI support is on the way.
115 * Remote targets can connect to a sub-program
117 A popen(3) style serial-device has been added. This device starts a
118 sub-process (such as a stand-alone simulator) and then communicates
119 with that. The sub-program to run is specified using the syntax
120 ``|<program> <args>'' vis:
122 (gdb) set remotedebug 1
123 (gdb) target extended-remote |mn10300-elf-sim program-args
125 * MIPS 64 remote protocol
127 A long standing bug in the mips64 remote protocol where by GDB
128 expected certain 32 bit registers (ex SR) to be transfered as 32
129 instead of 64 bits has been fixed.
131 The command ``set remote-mips64-transfers-32bit-regs on'' has been
132 added to provide backward compatibility with older versions of GDB.
134 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
136 The command ``set remotebinarydownload'' command has been replaced by
137 ``set remote X-packet''. Other commands in ``set remote'' family
138 include ``set remote P-packet''.
140 * Breakpoint commands accept ranges.
142 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
143 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
144 ``tracepoint passcount'' also accepts a range of tracepoints.
146 * ``apropos'' command added.
148 The ``apropos'' command searches through command names and
149 documentation strings, printing out matches, making it much easier to
150 try to find a command that does what you are looking for.
154 A new machine oriented interface (MI) has been added to GDB. This
155 interface is designed for debug environments running GDB as a separate
156 process. This is part of the long term libGDB project. See the
157 "GDB/MI" chapter of the GDB manual for further information. It can be
158 enabled by configuring with:
160 .../configure --enable-gdbmi
162 *** Changes in GDB-4.18:
164 * New native configurations
166 HP-UX 10.20 hppa*-*-hpux10.20
167 HP-UX 11.x hppa*-*-hpux11.0*
168 M68K Linux m68*-*-linux*
172 Fujitsu FR30 fr30-*-elf*
173 Intel StrongARM strongarm-*-*
174 Mitsubishi D30V d30v-*-*
176 * OBSOLETE configurations
178 Gould PowerNode, NP1 np1-*-*, pn-*-*
180 Configurations that have been declared obsolete will be commented out,
181 but the code will be left in place. If there is no activity to revive
182 these configurations before the next release of GDB, the sources will
183 be permanently REMOVED.
187 As a compatibility experiment, GDB's source files buildsym.h and
188 buildsym.c have been converted to pure standard C, no longer
189 containing any K&R compatibility code. We believe that all systems in
190 use today either come with a standard C compiler, or have a GCC port
191 available. If this is not true, please report the affected
192 configuration to bug-gdb@gnu.org immediately. See the README file for
193 information about getting a standard C compiler if you don't have one
198 GDB now uses readline 2.2.
200 * set extension-language
202 You can now control the mapping between filename extensions and source
203 languages by using the `set extension-language' command. For instance,
204 you can ask GDB to treat .c files as C++ by saying
205 set extension-language .c c++
206 The command `info extensions' lists all of the recognized extensions
207 and their associated languages.
209 * Setting processor type for PowerPC and RS/6000
211 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
212 you can use the `set processor' command to specify what variant of the
213 PowerPC family you are debugging. The command
217 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
218 following PowerPC and RS6000 variants:
220 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
221 rs6000 IBM RS6000 ("POWER") architecture, user-level view
223 403GC IBM PowerPC 403GC
224 505 Motorola PowerPC 505
225 860 Motorola PowerPC 860 or 850
226 601 Motorola PowerPC 601
227 602 Motorola PowerPC 602
228 603 Motorola/IBM PowerPC 603 or 603e
229 604 Motorola PowerPC 604 or 604e
230 750 Motorola/IBM PowerPC 750 or 750
232 At the moment, this command just tells GDB what to name the
233 special-purpose processor registers. Since almost all the affected
234 registers are inaccessible to user-level programs, this command is
235 only useful for remote debugging in its present form.
239 Thanks to a major code donation from Hewlett-Packard, GDB now has much
240 more extensive support for HP-UX. Added features include shared
241 library support, kernel threads and hardware watchpoints for 11.00,
242 support for HP's ANSI C and C++ compilers, and a compatibility mode
243 for xdb and dbx commands.
247 HP's donation includes the new concept of catchpoints, which is a
248 generalization of the old catch command. On HP-UX, it is now possible
249 to catch exec, fork, and vfork, as well as library loading.
251 This means that the existing catch command has changed; its first
252 argument now specifies the type of catch to be set up. See the
253 output of "help catch" for a list of catchpoint types.
255 * Debugging across forks
257 On HP-UX, you can choose which process to debug when a fork() happens
262 HP has donated a curses-based terminal user interface (TUI). To get
263 it, build with --enable-tui. Although this can be enabled for any
264 configuration, at present it only works for native HP debugging.
266 * GDB remote protocol additions
268 A new protocol packet 'X' that writes binary data is now available.
269 Default behavior is to try 'X', then drop back to 'M' if the stub
270 fails to respond. The settable variable `remotebinarydownload'
271 allows explicit control over the use of 'X'.
273 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
274 full 64-bit address. The command
276 set remoteaddresssize 32
278 can be used to revert to the old behaviour. For existing remote stubs
279 the change should not be noticed, as the additional address information
282 In order to assist in debugging stubs, you may use the maintenance
283 command `packet' to send any text string to the stub. For instance,
285 maint packet heythere
287 sends the packet "$heythere#<checksum>". Note that it is very easy to
288 disrupt a debugging session by sending the wrong packet at the wrong
291 The compare-sections command allows you to compare section data on the
292 target to what is in the executable file without uploading or
293 downloading, by comparing CRC checksums.
295 * Tracing can collect general expressions
297 You may now collect general expressions at tracepoints. This requires
298 further additions to the target-side stub; see tracepoint.c and
299 doc/agentexpr.texi for further details.
301 * mask-address variable for Mips
303 For Mips targets, you may control the zeroing of the upper 32 bits of
304 a 64-bit address by entering `set mask-address on'. This is mainly
305 of interest to users of embedded R4xxx and R5xxx processors.
307 * Higher serial baud rates
309 GDB's serial code now allows you to specify baud rates 57600, 115200,
310 230400, and 460800 baud. (Note that your host system may not be able
311 to achieve all of these rates.)
315 The i960 configuration now includes an initial implementation of a
316 builtin simulator, contributed by Jim Wilson.
319 *** Changes in GDB-4.17:
321 * New native configurations
323 Alpha GNU/Linux alpha*-*-linux*
324 Unixware 2.x i[3456]86-unixware2*
325 Irix 6.x mips*-sgi-irix6*
326 PowerPC GNU/Linux powerpc-*-linux*
327 PowerPC Solaris powerpcle-*-solaris*
328 Sparc GNU/Linux sparc-*-linux*
329 Motorola sysV68 R3V7.1 m68k-motorola-sysv
333 Argonaut Risc Chip (ARC) arc-*-*
334 Hitachi H8/300S h8300*-*-*
335 Matsushita MN10200 w/simulator mn10200-*-*
336 Matsushita MN10300 w/simulator mn10300-*-*
337 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
338 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
339 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
340 Mitsubishi D10V w/simulator d10v-*-*
341 Mitsubishi M32R/D w/simulator m32r-*-elf*
342 Tsqware Sparclet sparclet-*-*
343 NEC V850 w/simulator v850-*-*
345 * New debugging protocols
347 ARM with RDI protocol arm*-*-*
348 M68K with dBUG monitor m68*-*-{aout,coff,elf}
349 DDB and LSI variants of PMON protocol mips*-*-*
350 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
351 PowerPC with SDS protocol powerpc{,le}-*-eabi
352 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
356 All configurations can now understand and use the DWARF 2 debugging
357 format. The choice is automatic, if the symbol file contains DWARF 2
362 GDB now includes basic Java language support. This support is
363 only useful with Java compilers that produce native machine code.
365 * solib-absolute-prefix and solib-search-path
367 For SunOS and SVR4 shared libraries, you may now set the prefix for
368 loading absolute shared library symbol files, and the search path for
369 locating non-absolute shared library symbol files.
371 * Live range splitting
373 GDB can now effectively debug code for which GCC has performed live
374 range splitting as part of its optimization. See gdb/doc/LRS for
375 more details on the expected format of the stabs information.
379 GDB's support for the GNU Hurd, including thread debugging, has been
380 updated to work with current versions of the Hurd.
384 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
385 instruction set. ARM GDB automatically detects when Thumb
386 instructions are in use, and adjusts disassembly and backtracing
391 GDB's MIPS target configurations now handle the MIP16 16-bit
396 GDB now includes support for overlays; if an executable has been
397 linked such that multiple sections are based at the same address, GDB
398 will decide which section to use for symbolic info. You can choose to
399 control the decision manually, using overlay commands, or implement
400 additional target-side support and use "overlay load-target" to bring
401 in the overlay mapping. Do "help overlay" for more detail.
405 The command "info symbol <address>" displays information about
406 the symbol at the specified address.
410 The standard remote protocol now includes an extension that allows
411 asynchronous collection and display of trace data. This requires
412 extensive support in the target-side debugging stub. Tracing mode
413 includes a new interaction mode in GDB and new commands: see the
414 file tracepoint.c for more details.
418 Configurations for embedded MIPS now include a simulator contributed
419 by Cygnus Solutions. The simulator supports the instruction sets
420 of most MIPS variants.
424 Sparc configurations may now include the ERC32 simulator contributed
425 by the European Space Agency. The simulator is not built into
426 Sparc targets by default; configure with --enable-sim to include it.
430 For target configurations that may include multiple variants of a
431 basic architecture (such as MIPS and SH), you may now set the
432 architecture explicitly. "set arch" sets, "info arch" lists
433 the possible architectures.
435 *** Changes in GDB-4.16:
437 * New native configurations
439 Windows 95, x86 Windows NT i[345]86-*-cygwin32
440 M68K NetBSD m68k-*-netbsd*
441 PowerPC AIX 4.x powerpc-*-aix*
442 PowerPC MacOS powerpc-*-macos*
443 PowerPC Windows NT powerpcle-*-cygwin32
444 RS/6000 AIX 4.x rs6000-*-aix4*
448 ARM with RDP protocol arm-*-*
449 I960 with MON960 i960-*-coff
450 MIPS VxWorks mips*-*-vxworks*
451 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
452 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
454 Matra Sparclet sparclet-*-*
458 The powerpc-eabi configuration now includes the PSIM simulator,
459 contributed by Andrew Cagney, with assistance from Mike Meissner.
460 PSIM is a very elaborate model of the PowerPC, including not only
461 basic instruction set execution, but also details of execution unit
462 performance and I/O hardware. See sim/ppc/README for more details.
466 GDB now works with Solaris 2.5.
468 * Windows 95/NT native
470 GDB will now work as a native debugger on Windows 95 and Windows NT.
471 To build it from source, you must use the "gnu-win32" environment,
472 which uses a DLL to emulate enough of Unix to run the GNU tools.
473 Further information, binaries, and sources are available at
474 ftp.cygnus.com, under pub/gnu-win32.
476 * dont-repeat command
478 If a user-defined command includes the command `dont-repeat', then the
479 command will not be repeated if the user just types return. This is
480 useful if the command is time-consuming to run, so that accidental
481 extra keystrokes don't run the same command many times.
483 * Send break instead of ^C
485 The standard remote protocol now includes an option to send a break
486 rather than a ^C to the target in order to interrupt it. By default,
487 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
489 * Remote protocol timeout
491 The standard remote protocol includes a new variable `remotetimeout'
492 that allows you to set the number of seconds before GDB gives up trying
493 to read from the target. The default value is 2.
495 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
497 By default GDB will automatically keep track of objects as they are
498 loaded and unloaded by the dynamic linker. By using the command `set
499 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
500 when shared library events occur, thus allowing you to set breakpoints
501 in shared libraries which are explicitly loaded by the inferior.
503 Note this feature does not work on hpux8. On hpux9 you must link
504 /usr/lib/end.o into your program. This feature should work
505 automatically on hpux10.
507 * Irix 5.x hardware watchpoint support
509 Irix 5 configurations now support the use of hardware watchpoints.
511 * Mips protocol "SYN garbage limit"
513 When debugging a Mips target using the `target mips' protocol, you
514 may set the number of characters that GDB will ignore by setting
515 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
516 every character. The default value is 1050.
518 * Recording and replaying remote debug sessions
520 If you set `remotelogfile' to the name of a file, gdb will write to it
521 a recording of a remote debug session. This recording may then be
522 replayed back to gdb using "gdbreplay". See gdbserver/README for
523 details. This is useful when you have a problem with GDB while doing
524 remote debugging; you can make a recording of the session and send it
525 to someone else, who can then recreate the problem.
527 * Speedups for remote debugging
529 GDB includes speedups for downloading and stepping MIPS systems using
530 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
531 and more efficient S-record downloading.
533 * Memory use reductions and statistics collection
535 GDB now uses less memory and reports statistics about memory usage.
536 Try the `maint print statistics' command, for example.
538 *** Changes in GDB-4.15:
542 The symbol reader for AIX GDB now uses partial symbol tables. This
543 can greatly improve startup time, especially for large executables.
545 * Remote targets use caching
547 Remote targets now use a data cache to speed up communication with the
548 remote side. The data cache could lead to incorrect results because
549 it doesn't know about volatile variables, thus making it impossible to
550 debug targets which use memory mapped I/O devices. `set remotecache
551 off' turns the the data cache off.
553 * Remote targets may have threads
555 The standard remote protocol now includes support for multiple threads
556 in the target system, using new protocol commands 'H' and 'T'. See
557 gdb/remote.c for details.
561 If GDB is configured with `--enable-netrom', then it will include
562 support for the NetROM ROM emulator from XLNT Designs. The NetROM
563 acts as though it is a bank of ROM on the target board, but you can
564 write into it over the network. GDB's support consists only of
565 support for fast loading into the emulated ROM; to debug, you must use
566 another protocol, such as standard remote protocol. The usual
567 sequence is something like
569 target nrom <netrom-hostname>
571 target remote <netrom-hostname>:1235
575 GDB now includes support for the Apple Macintosh, as a host only. It
576 may be run as either an MPW tool or as a standalone application, and
577 it can debug through the serial port. All the usual GDB commands are
578 available, but to the target command, you must supply "serial" as the
579 device type instead of "/dev/ttyXX". See mpw-README in the main
580 directory for more information on how to build. The MPW configuration
581 scripts */mpw-config.in support only a few targets, and only the
582 mips-idt-ecoff target has been tested.
586 GDB configuration now uses autoconf. This is not user-visible,
587 but does simplify configuration and building.
591 GDB now supports hpux10.
593 *** Changes in GDB-4.14:
595 * New native configurations
597 x86 FreeBSD i[345]86-*-freebsd
598 x86 NetBSD i[345]86-*-netbsd
599 NS32k NetBSD ns32k-*-netbsd
600 Sparc NetBSD sparc-*-netbsd
604 A29K VxWorks a29k-*-vxworks
605 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
606 CPU32 EST-300 emulator m68*-*-est*
607 PowerPC ELF powerpc-*-elf
610 * Alpha OSF/1 support for procfs
612 GDB now supports procfs under OSF/1-2.x and higher, which makes it
613 possible to attach to running processes. As the mounting of the /proc
614 filesystem is optional on the Alpha, GDB automatically determines
615 the availability of /proc during startup. This can lead to problems
616 if /proc is unmounted after GDB has been started.
618 * Arguments to user-defined commands
620 User commands may accept up to 10 arguments separated by whitespace.
621 Arguments are accessed within the user command via $arg0..$arg9. A
624 print $arg0 + $arg1 + $arg2
626 To execute the command use:
629 Defines the command "adder" which prints the sum of its three arguments.
630 Note the arguments are text substitutions, so they may reference variables,
631 use complex expressions, or even perform inferior function calls.
633 * New `if' and `while' commands
635 This makes it possible to write more sophisticated user-defined
636 commands. Both commands take a single argument, which is the
637 expression to evaluate, and must be followed by the commands to
638 execute, one per line, if the expression is nonzero, the list being
639 terminated by the word `end'. The `if' command list may include an
640 `else' word, which causes the following commands to be executed only
641 if the expression is zero.
643 * Fortran source language mode
645 GDB now includes partial support for Fortran 77. It will recognize
646 Fortran programs and can evaluate a subset of Fortran expressions, but
647 variables and functions may not be handled correctly. GDB will work
648 with G77, but does not yet know much about symbols emitted by other
651 * Better HPUX support
653 Most debugging facilities now work on dynamic executables for HPPAs
654 running hpux9 or later. You can attach to running dynamically linked
655 processes, but by default the dynamic libraries will be read-only, so
656 for instance you won't be able to put breakpoints in them. To change
657 that behavior do the following before running the program:
663 This will cause the libraries to be mapped private and read-write.
664 To revert to the normal behavior, do this:
670 You cannot set breakpoints or examine data in the library until after
671 the library is loaded if the function/data symbols do not have
674 GDB can now also read debug symbols produced by the HP C compiler on
675 HPPAs (sorry, no C++, Fortran or 68k support).
677 * Target byte order now dynamically selectable
679 You can choose which byte order to use with a target system, via the
680 commands "set endian big" and "set endian little", and you can see the
681 current setting by using "show endian". You can also give the command
682 "set endian auto", in which case GDB will use the byte order
683 associated with the executable. Currently, only embedded MIPS
684 configurations support dynamic selection of target byte order.
686 * New DOS host serial code
688 This version uses DPMI interrupts to handle buffered I/O, so you
689 no longer need to run asynctsr when debugging boards connected to
692 *** Changes in GDB-4.13:
694 * New "complete" command
696 This lists all the possible completions for the rest of the line, if it
697 were to be given as a command itself. This is intended for use by emacs.
699 * Trailing space optional in prompt
701 "set prompt" no longer adds a space for you after the prompt you set. This
702 allows you to set a prompt which ends in a space or one that does not.
704 * Breakpoint hit counts
706 "info break" now displays a count of the number of times the breakpoint
707 has been hit. This is especially useful in conjunction with "ignore"; you
708 can ignore a large number of breakpoint hits, look at the breakpoint info
709 to see how many times the breakpoint was hit, then run again, ignoring one
710 less than that number, and this will get you quickly to the last hit of
713 * Ability to stop printing at NULL character
715 "set print null-stop" will cause GDB to stop printing the characters of
716 an array when the first NULL is encountered. This is useful when large
717 arrays actually contain only short strings.
719 * Shared library breakpoints
721 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
722 breakpoints in shared libraries before the executable is run.
724 * Hardware watchpoints
726 There is a new hardware breakpoint for the watch command for sparclite
727 targets. See gdb/sparclite/hw_breakpoint.note.
729 Hardware watchpoints are also now supported under Linux.
733 Annotations have been added. These are for use with graphical interfaces,
734 and are still experimental. Currently only gdba.el uses these.
736 * Improved Irix 5 support
738 GDB now works properly with Irix 5.2.
740 * Improved HPPA support
742 GDB now works properly with the latest GCC and GAS.
744 * New native configurations
746 Sequent PTX4 i[34]86-sequent-ptx4
747 HPPA running OSF/1 hppa*-*-osf*
748 Atari TT running SVR4 m68*-*-sysv4*
749 RS/6000 LynxOS rs6000-*-lynxos*
753 OS/9000 i[34]86-*-os9k
754 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
757 * Hitachi SH7000 and E7000-PC ICE support
759 There is now support for communicating with the Hitachi E7000-PC ICE.
760 This is available automatically when GDB is configured for the SH.
764 As usual, a variety of small fixes and improvements, both generic
765 and configuration-specific. See the ChangeLog for more detail.
767 *** Changes in GDB-4.12:
769 * Irix 5 is now supported
773 GDB-4.12 on the HPPA has a number of changes which make it unable
774 to debug the output from the currently released versions of GCC and
775 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
776 of GCC and GAS, versions of these tools designed to work with GDB-4.12
777 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
780 *** Changes in GDB-4.11:
782 * User visible changes:
786 The "set remotedebug" option is now consistent between the mips remote
787 target, remote targets using the gdb-specific protocol, UDI (AMD's
788 debug protocol for the 29k) and the 88k bug monitor. It is now an
789 integer specifying a debug level (normally 0 or 1, but 2 means more
790 debugging info for the mips target).
792 * DEC Alpha native support
794 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
795 debug info, but GDB works fairly well with the DEC compiler and should
796 work with a future GCC release. See the README file for a few
797 Alpha-specific notes.
799 * Preliminary thread implementation
801 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
803 * LynxOS native and target support for 386
805 This release has been hosted on LynxOS 2.2, and also can be configured
806 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
809 * Improvements in C++ mangling/demangling.
811 This release has much better g++ debugging, specifically in name
812 mangling/demangling, virtual function calls, print virtual table,
813 call methods, ...etc.
815 *** Changes in GDB-4.10:
817 * User visible changes:
819 Remote debugging using the GDB-specific (`target remote') protocol now
820 supports the `load' command. This is only useful if you have some
821 other way of getting the stub to the target system, and you can put it
822 somewhere in memory where it won't get clobbered by the download.
824 Filename completion now works.
826 When run under emacs mode, the "info line" command now causes the
827 arrow to point to the line specified. Also, "info line" prints
828 addresses in symbolic form (as well as hex).
830 All vxworks based targets now support a user settable option, called
831 vxworks-timeout. This option represents the number of seconds gdb
832 should wait for responses to rpc's. You might want to use this if
833 your vxworks target is, perhaps, a slow software simulator or happens
834 to be on the far side of a thin network line.
838 This release contains support for using a DEC alpha as a GDB host for
839 cross debugging. Native alpha debugging is not supported yet.
842 *** Changes in GDB-4.9:
846 This is the first GDB release which is accompanied by a matching testsuite.
847 The testsuite requires installation of dejagnu, which should be available
848 via ftp from most sites that carry GNU software.
852 'Cfront' style demangling has had its name changed to 'ARM' style, to
853 emphasize that it was written from the specifications in the C++ Annotated
854 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
855 disclaimers, it still generated too much confusion with users attempting to
856 use gdb with AT&T cfront.
860 GDB now uses a standard remote interface to a simulator library.
861 So far, the library contains simulators for the Zilog Z8001/2, the
862 Hitachi H8/300, H8/500 and Super-H.
864 * New targets supported
866 H8/300 simulator h8300-hitachi-hms or h8300hms
867 H8/500 simulator h8500-hitachi-hms or h8500hms
868 SH simulator sh-hitachi-hms or sh
869 Z8000 simulator z8k-zilog-none or z8ksim
870 IDT MIPS board over serial line mips-idt-ecoff
872 Cross-debugging to GO32 targets is supported. It requires a custom
873 version of the i386-stub.c module which is integrated with the
874 GO32 memory extender.
876 * New remote protocols
878 MIPS remote debugging protocol.
880 * New source languages supported
882 This version includes preliminary support for Chill, a Pascal like language
883 used by telecommunications companies. Chill support is also being integrated
884 into the GNU compiler, but we don't know when it will be publically available.
887 *** Changes in GDB-4.8:
889 * HP Precision Architecture supported
891 GDB now supports HP PA-RISC machines running HPUX. A preliminary
892 version of this support was available as a set of patches from the
893 University of Utah. GDB does not support debugging of programs
894 compiled with the HP compiler, because HP will not document their file
895 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
896 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
898 Many problems in the preliminary version have been fixed.
900 * Faster and better demangling
902 We have improved template demangling and fixed numerous bugs in the GNU style
903 demangler. It can now handle type modifiers such as `static' or `const'. Wide
904 character types (wchar_t) are now supported. Demangling of each symbol is now
905 only done once, and is cached when the symbol table for a file is read in.
906 This results in a small increase in memory usage for C programs, a moderate
907 increase in memory usage for C++ programs, and a fantastic speedup in
910 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
911 from the specifications in the Annotated Reference Manual, which AT&T's
912 compiler does not actually implement.
914 * G++ multiple inheritance compiler problem
916 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
917 inheritance lattices was reworked to properly discover ambiguities. We
918 recently found an example which causes this new algorithm to fail in a
919 very subtle way, producing bad debug information for those classes.
920 The file 'gcc.patch' (in this directory) can be applied to gcc to
921 circumvent the problem. A future GCC release will contain a complete
924 The previous G++ debug info problem (mentioned below for the gdb-4.7
925 release) is fixed in gcc version 2.3.2.
927 * Improved configure script
929 The `configure' script will now attempt to guess your system type if
930 you don't supply a host system type. The old scheme of supplying a
931 host system triplet is preferable over using this. All the magic is
932 done in the new `config.guess' script. Examine it for details.
934 We have also brought our configure script much more in line with the FSF's
935 version. It now supports the --with-xxx options. In particular,
936 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
937 The resulting GDB will not be able to read arbitrary object file formats --
938 only the format ``expected'' to be used on the configured target system.
939 We hope to make this the default in a future release.
941 * Documentation improvements
943 There's new internal documentation on how to modify GDB, and how to
944 produce clean changes to the code. We implore people to read it
945 before submitting changes.
947 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
948 M4 macros. The new texinfo.tex is provided in this release. Pre-built
949 `info' files are also provided. To build `info' files from scratch,
950 you will need the latest `makeinfo' release, which will be available in
951 a future texinfo-X.Y release.
953 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
954 We're not sure exactly which versions have this problem, but it has
955 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
956 or better. If that isn't possible, there is a patch in
957 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
962 GDB now supports array constants that can be used in expressions typed in by
963 the user. The syntax is `{element, element, ...}'. Ie: you can now type
964 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
967 The new directory `gdb/sparclite' contains a program that demonstrates
968 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
970 * New native hosts supported
972 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
973 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
975 * New targets supported
977 AMD 29k family via UDI a29k-amd-udi or udi29k
979 * New file formats supported
981 BFD now supports reading HP/PA-RISC executables (SOM file format?),
982 HPUX core files, and SCO 3.2v2 core files.
986 Attaching to processes now works again; thanks for the many bug reports.
988 We have also stomped on a bunch of core dumps caused by
989 printf_filtered("%s") problems.
991 We eliminated a copyright problem on the rpc and ptrace header files
992 for VxWorks, which was discovered at the last minute during the 4.7
993 release. You should now be able to build a VxWorks GDB.
995 You can now interrupt gdb while an attached process is running. This
996 will cause the attached process to stop, and give control back to GDB.
998 We fixed problems caused by using too many file descriptors
999 for reading symbols from object files and libraries. This was
1000 especially a problem for programs that used many (~100) shared
1003 The `step' command now only enters a subroutine if there is line number
1004 information for the subroutine. Otherwise it acts like the `next'
1005 command. Previously, `step' would enter subroutines if there was
1006 any debugging information about the routine. This avoids problems
1007 when using `cc -g1' on MIPS machines.
1009 * Internal improvements
1011 GDB's internal interfaces have been improved to make it easier to support
1012 debugging of multiple languages in the future.
1014 GDB now uses a common structure for symbol information internally.
1015 Minimal symbols (derived from linkage symbols in object files), partial
1016 symbols (from a quick scan of debug information), and full symbols
1017 contain a common subset of information, making it easier to write
1018 shared code that handles any of them.
1020 * New command line options
1022 We now accept --silent as an alias for --quiet.
1026 The memory-mapped-malloc library is now licensed under the GNU Library
1027 General Public License.
1029 *** Changes in GDB-4.7:
1031 * Host/native/target split
1033 GDB has had some major internal surgery to untangle the support for
1034 hosts and remote targets. Now, when you configure GDB for a remote
1035 target, it will no longer load in all of the support for debugging
1036 local programs on the host. When fully completed and tested, this will
1037 ensure that arbitrary host/target combinations are possible.
1039 The primary conceptual shift is to separate the non-portable code in
1040 GDB into three categories. Host specific code is required any time GDB
1041 is compiled on that host, regardless of the target. Target specific
1042 code relates to the peculiarities of the target, but can be compiled on
1043 any host. Native specific code is everything else: it can only be
1044 built when the host and target are the same system. Child process
1045 handling and core file support are two common `native' examples.
1047 GDB's use of /proc for controlling Unix child processes is now cleaner.
1048 It has been split out into a single module under the `target_ops' vector,
1049 plus two native-dependent functions for each system that uses /proc.
1051 * New hosts supported
1053 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1054 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1055 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1057 * New targets supported
1059 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1060 68030 and CPU32 m68030-*-*, m68332-*-*
1062 * New native hosts supported
1064 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1065 (386bsd is not well tested yet)
1066 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1068 * New file formats supported
1070 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1071 supports reading of `a.out.adobe' object files, which are an a.out
1072 format extended with minimal information about multiple sections.
1076 `show copying' is the same as the old `info copying'.
1077 `show warranty' is the same as `info warrantee'.
1078 These were renamed for consistency. The old commands continue to work.
1080 `info handle' is a new alias for `info signals'.
1082 You can now define pre-command hooks, which attach arbitrary command
1083 scripts to any command. The commands in the hook will be executed
1084 prior to the user's command. You can also create a hook which will be
1085 executed whenever the program stops. See gdb.texinfo.
1089 We now deal with Cfront style name mangling, and can even extract type
1090 info from mangled symbols. GDB can automatically figure out which
1091 symbol mangling style your C++ compiler uses.
1093 Calling of methods and virtual functions has been improved as well.
1097 The crash that occured when debugging Sun Ansi-C compiled binaries is
1098 fixed. This was due to mishandling of the extra N_SO stabs output
1101 We also finally got Ultrix 4.2 running in house, and fixed core file
1102 support, with help from a dozen people on the net.
1104 John M. Farrell discovered that the reason that single-stepping was so
1105 slow on all of the Mips based platforms (primarily SGI and DEC) was
1106 that we were trying to demangle and lookup a symbol used for internal
1107 purposes on every instruction that was being stepped through. Changing
1108 the name of that symbol so that it couldn't be mistaken for a C++
1109 mangled symbol sped things up a great deal.
1111 Rich Pixley sped up symbol lookups in general by getting much smarter
1112 about when C++ symbol mangling is necessary. This should make symbol
1113 completion (TAB on the command line) much faster. It's not as fast as
1114 we'd like, but it's significantly faster than gdb-4.6.
1118 A new user controllable variable 'call_scratch_address' can
1119 specify the location of a scratch area to be used when GDB
1120 calls a function in the target. This is necessary because the
1121 usual method of putting the scratch area on the stack does not work
1122 in systems that have separate instruction and data spaces.
1124 We integrated changes to support the 29k UDI (Universal Debugger
1125 Interface), but discovered at the last minute that we didn't have all
1126 of the appropriate copyright paperwork. We are working with AMD to
1127 resolve this, and hope to have it available soon.
1131 We have sped up the remote serial line protocol, especially for targets
1132 with lots of registers. It now supports a new `expedited status' ('T')
1133 message which can be used in place of the existing 'S' status message.
1134 This allows the remote stub to send only the registers that GDB
1135 needs to make a quick decision about single-stepping or conditional
1136 breakpoints, eliminating the need to fetch the entire register set for
1137 each instruction being stepped through.
1139 The GDB remote serial protocol now implements a write-through cache for
1140 registers, only re-reading the registers if the target has run.
1142 There is also a new remote serial stub for SPARC processors. You can
1143 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1144 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1145 processor with a serial port.
1149 Configure.in files have become much easier to read and modify. A new
1150 `table driven' format makes it more obvious what configurations are
1151 supported, and what files each one uses.
1155 There is a new opcodes library which will eventually contain all of the
1156 disassembly routines and opcode tables. At present, it only contains
1157 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1158 disassembler (binutils/objdump) to share these routines.
1160 The libiberty library is now copylefted under the GNU Library General
1161 Public License. This allows more liberal use, and was done so libg++
1162 can use it. This makes no difference to GDB, since the Library License
1163 grants all the rights from the General Public License.
1167 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1168 reference to the stabs symbol info used by the debugger. It is (as far
1169 as we know) the only published document on this fascinating topic. We
1170 encourage you to read it, compare it to the stabs information on your
1171 system, and send improvements on the document in general (to
1172 bug-gdb@prep.ai.mit.edu).
1174 And, of course, many bugs have been fixed.
1177 *** Changes in GDB-4.6:
1179 * Better support for C++ function names
1181 GDB now accepts as input the "demangled form" of C++ overloaded function
1182 names and member function names, and can do command completion on such names
1183 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1184 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1185 Make use of command completion, it is your friend.
1187 GDB also now accepts a variety of C++ mangled symbol formats. They are
1188 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1189 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1190 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1191 for the list of formats.
1193 * G++ symbol mangling problem
1195 Recent versions of gcc have a bug in how they emit debugging information for
1196 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1197 directory) can be applied to gcc to fix the problem. Alternatively, if you
1198 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1199 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1200 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1203 * New 'maintenance' command
1205 All of the commands related to hacking GDB internals have been moved out of
1206 the main command set, and now live behind the 'maintenance' command. This
1207 can also be abbreviated as 'mt'. The following changes were made:
1209 dump-me -> maintenance dump-me
1210 info all-breakpoints -> maintenance info breakpoints
1211 printmsyms -> maintenance print msyms
1212 printobjfiles -> maintenance print objfiles
1213 printpsyms -> maintenance print psymbols
1214 printsyms -> maintenance print symbols
1216 The following commands are new:
1218 maintenance demangle Call internal GDB demangler routine to
1219 demangle a C++ link name and prints the result.
1220 maintenance print type Print a type chain for a given symbol
1222 * Change to .gdbinit file processing
1224 We now read the $HOME/.gdbinit file before processing the argv arguments
1225 (e.g. reading symbol files or core files). This allows global parameters to
1226 be set, which will apply during the symbol reading. The ./.gdbinit is still
1227 read after argv processing.
1229 * New hosts supported
1231 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1233 Linux support i386-unknown-linux or linux
1235 We are also including code to support the HP/PA running BSD and HPUX. This
1236 is almost guaranteed not to work, as we didn't have time to test or build it
1237 for this release. We are including it so that the more adventurous (or
1238 masochistic) of you can play with it. We also had major problems with the
1239 fact that the compiler that we got from HP doesn't support the -g option.
1242 * New targets supported
1244 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1246 * More smarts about finding #include files
1248 GDB now remembers the compilation directory for all include files, and for
1249 all files from which C is generated (like yacc and lex sources). This
1250 greatly improves GDB's ability to find yacc/lex sources, and include files,
1251 especially if you are debugging your program from a directory different from
1252 the one that contains your sources.
1254 We also fixed a bug which caused difficulty with listing and setting
1255 breakpoints in include files which contain C code. (In the past, you had to
1256 try twice in order to list an include file that you hadn't looked at before.)
1258 * Interesting infernals change
1260 GDB now deals with arbitrary numbers of sections, where the symbols for each
1261 section must be relocated relative to that section's landing place in the
1262 target's address space. This work was needed to support ELF with embedded
1263 stabs used by Solaris-2.0.
1265 * Bug fixes (of course!)
1267 There have been loads of fixes for the following things:
1268 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1269 i960, stabs, DOS(GO32), procfs, etc...
1271 See the ChangeLog for details.
1273 *** Changes in GDB-4.5:
1275 * New machines supported (host and target)
1277 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1279 SGI Irix-4.x mips-sgi-irix4 or iris4
1281 * New malloc package
1283 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1284 Mmalloc is capable of handling mutiple heaps of memory. It is also
1285 capable of saving a heap to a file, and then mapping it back in later.
1286 This can be used to greatly speedup the startup of GDB by using a
1287 pre-parsed symbol table which lives in a mmalloc managed heap. For
1288 more details, please read mmalloc/mmalloc.texi.
1292 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1293 'help info proc' for details.
1295 * MIPS ecoff symbol table format
1297 The code that reads MIPS symbol table format is now supported on all hosts.
1298 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1301 * File name changes for MS-DOS
1303 Many files in the config directories have been renamed to make it easier to
1304 support GDB on MS-DOSe systems (which have very restrictive file name
1305 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1306 environment) is close to working but has some remaining problems. Note
1307 that debugging of DOS programs is not supported, due to limitations
1308 in the ``operating system'', but it can be used to host cross-debugging.
1310 * Cross byte order fixes
1312 Many fixes have been made to support cross debugging of Sparc and MIPS
1313 targets from hosts whose byte order differs.
1315 * New -mapped and -readnow options
1317 If memory-mapped files are available on your system through the 'mmap'
1318 system call, you can use the -mapped option on the `file' or
1319 `symbol-file' commands to cause GDB to write the symbols from your
1320 program into a reusable file. If the program you are debugging is
1321 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1322 Future GDB debugging sessions will notice the presence of this file,
1323 and will quickly map in symbol information from it, rather than reading
1324 the symbol table from the executable program. Using the '-mapped'
1325 option in a GDB `file' or `symbol-file' command has the same effect as
1326 starting GDB with the '-mapped' command-line option.
1328 You can cause GDB to read the entire symbol table immediately by using
1329 the '-readnow' option with any of the commands that load symbol table
1330 information (or on the GDB command line). This makes the command
1331 slower, but makes future operations faster.
1333 The -mapped and -readnow options are typically combined in order to
1334 build a `fred.syms' file that contains complete symbol information.
1335 A simple GDB invocation to do nothing but build a `.syms' file for future
1338 gdb -batch -nx -mapped -readnow programname
1340 The `.syms' file is specific to the host machine on which GDB is run.
1341 It holds an exact image of GDB's internal symbol table. It cannot be
1342 shared across multiple host platforms.
1344 * longjmp() handling
1346 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1347 siglongjmp() without losing control. This feature has not yet been ported to
1348 all systems. It currently works on many 386 platforms, all MIPS-based
1349 platforms (SGI, DECstation, etc), and Sun3/4.
1353 Preliminary work has been put in to support the new Solaris OS from Sun. At
1354 this time, it can control and debug processes, but it is not capable of
1359 As always, many many bug fixes. The major areas were with g++, and mipsread.
1360 People using the MIPS-based platforms should experience fewer mysterious
1361 crashes and trashed symbol tables.
1363 *** Changes in GDB-4.4:
1365 * New machines supported (host and target)
1367 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1369 BSD Reno on Vax vax-dec-bsd
1370 Ultrix on Vax vax-dec-ultrix
1372 * New machines supported (target)
1374 AMD 29000 embedded, using EBMON a29k-none-none
1378 GDB continues to improve its handling of C++. `References' work better.
1379 The demangler has also been improved, and now deals with symbols mangled as
1380 per the Annotated C++ Reference Guide.
1382 GDB also now handles `stabs' symbol information embedded in MIPS
1383 `ecoff' symbol tables. Since the ecoff format was not easily
1384 extensible to handle new languages such as C++, this appeared to be a
1385 good way to put C++ debugging info into MIPS binaries. This option
1386 will be supported in the GNU C compiler, version 2, when it is
1389 * New features for SVR4
1391 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1392 shared libraries. Debugging dynamically linked programs should present
1393 only minor differences from debugging statically linked programs.
1395 The `info proc' command will print out information about any process
1396 on an SVR4 system (including the one you are debugging). At the moment,
1397 it prints the address mappings of the process.
1399 If you bring up GDB on another SVR4 system, please send mail to
1400 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1402 * Better dynamic linking support in SunOS
1404 Reading symbols from shared libraries which contain debugging symbols
1405 now works properly. However, there remain issues such as automatic
1406 skipping of `transfer vector' code during function calls, which
1407 make it harder to debug code in a shared library, than to debug the
1408 same code linked statically.
1412 GDB is now using the latest `getopt' routines from the FSF. This
1413 version accepts the -- prefix for options with long names. GDB will
1414 continue to accept the old forms (-option and +option) as well.
1415 Various single letter abbreviations for options have been explicity
1416 added to the option table so that they won't get overshadowed in the
1417 future by other options that begin with the same letter.
1421 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1422 Many assorted bugs have been handled. Many more remain to be handled.
1423 See the various ChangeLog files (primarily in gdb and bfd) for details.
1426 *** Changes in GDB-4.3:
1428 * New machines supported (host and target)
1430 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1431 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1432 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1434 * Almost SCO Unix support
1436 We had hoped to support:
1437 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1438 (except for core file support), but we discovered very late in the release
1439 that it has problems with process groups that render gdb unusable. Sorry
1440 about that. I encourage people to fix it and post the fixes.
1442 * Preliminary ELF and DWARF support
1444 GDB can read ELF object files on System V Release 4, and can handle
1445 debugging records for C, in DWARF format, in ELF files. This support
1446 is preliminary. If you bring up GDB on another SVR4 system, please
1447 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1452 GDB now uses the latest `readline' library. One user-visible change
1453 is that two tabs will list possible command completions, which previously
1454 required typing M-? (meta-question mark, or ESC ?).
1458 The `stepi' bug that many of you noticed has been squashed.
1459 Many bugs in C++ have been handled. Many more remain to be handled.
1460 See the various ChangeLog files (primarily in gdb and bfd) for details.
1462 * State of the MIPS world (in case you wondered):
1464 GDB can understand the symbol tables emitted by the compilers
1465 supplied by most vendors of MIPS-based machines, including DEC. These
1466 symbol tables are in a format that essentially nobody else uses.
1468 Some versions of gcc come with an assembler post-processor called
1469 mips-tfile. This program is required if you want to do source-level
1470 debugging of gcc-compiled programs. I believe FSF does not ship
1471 mips-tfile with gcc version 1, but it will eventually come with gcc
1474 Debugging of g++ output remains a problem. g++ version 1.xx does not
1475 really support it at all. (If you're lucky, you should be able to get
1476 line numbers and stack traces to work, but no parameters or local
1477 variables.) With some work it should be possible to improve the
1480 When gcc version 2 is released, you will have somewhat better luck.
1481 However, even then you will get confusing results for inheritance and
1484 We will eventually provide full debugging of g++ output on
1485 DECstations. This will probably involve some kind of stabs-in-ecoff
1486 encapulation, but the details have not been worked out yet.
1489 *** Changes in GDB-4.2:
1491 * Improved configuration
1493 Only one copy of `configure' exists now, and it is not self-modifying.
1494 Porting BFD is simpler.
1498 The `step' and `next' commands now only stop at the first instruction
1499 of a source line. This prevents the multiple stops that used to occur
1500 in switch statements, for-loops, etc. `Step' continues to stop if a
1501 function that has debugging information is called within the line.
1505 Lots of small bugs fixed. More remain.
1507 * New host supported (not target)
1509 Intel 386 PC clone running Mach i386-none-mach
1512 *** Changes in GDB-4.1:
1514 * Multiple source language support
1516 GDB now has internal scaffolding to handle several source languages.
1517 It determines the type of each source file from its filename extension,
1518 and will switch expression parsing and number formatting to match the
1519 language of the function in the currently selected stack frame.
1520 You can also specifically set the language to be used, with
1521 `set language c' or `set language modula-2'.
1525 GDB now has preliminary support for the GNU Modula-2 compiler,
1526 currently under development at the State University of New York at
1527 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1528 continue through the fall of 1991 and into 1992.
1530 Other Modula-2 compilers are currently not supported, and attempting to
1531 debug programs compiled with them will likely result in an error as the
1532 symbol table is read. Feel free to work on it, though!
1534 There are hooks in GDB for strict type checking and range checking,
1535 in the `Modula-2 philosophy', but they do not currently work.
1539 GDB can now write to executable and core files (e.g. patch
1540 a variable's value). You must turn this switch on, specify
1541 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1542 by assigning a new value to a variable. Modifications take
1545 * Automatic SunOS shared library reading
1547 When you run your program, GDB automatically determines where its
1548 shared libraries (if any) have been loaded, and reads their symbols.
1549 The `share' command is no longer needed. This also works when
1550 examining core files.
1554 You can specify the number of lines that the `list' command shows.
1557 * New machines supported (host and target)
1559 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1560 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1561 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1563 * New hosts supported (not targets)
1565 IBM RT/PC: romp-ibm-aix or rtpc
1567 * New targets supported (not hosts)
1569 AMD 29000 embedded with COFF a29k-none-coff
1570 AMD 29000 embedded with a.out a29k-none-aout
1571 Ultracomputer remote kernel debug a29k-nyu-kern
1573 * New remote interfaces
1579 *** Changes in GDB-4.0:
1583 Wide output is wrapped at good places to make the output more readable.
1585 Gdb now supports cross-debugging from a host machine of one type to a
1586 target machine of another type. Communication with the target system
1587 is over serial lines. The ``target'' command handles connecting to the
1588 remote system; the ``load'' command will download a program into the
1589 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1590 also supports debugging of realtime processes running under VxWorks,
1591 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1592 stub on the target system.
1594 New CPUs supported include the AMD 29000 and Intel 960.
1596 GDB now reads object files and symbol tables via a ``binary file''
1597 library, which allows a single copy of GDB to debug programs of multiple
1598 object file types such as a.out and coff.
1600 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1601 refcard.dvi and refcard.ps are available to format it).
1604 * Control-Variable user interface simplified
1606 All variables that control the operation of the debugger can be set
1607 by the ``set'' command, and displayed by the ``show'' command.
1609 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1610 ``Show prompt'' produces the response:
1611 Gdb's prompt is new-gdb=>.
1613 What follows are the NEW set commands. The command ``help set'' will
1614 print a complete list of old and new set commands. ``help set FOO''
1615 will give a longer description of the variable FOO. ``show'' will show
1616 all of the variable descriptions and their current settings.
1618 confirm on/off: Enables warning questions for operations that are
1619 hard to recover from, e.g. rerunning the program while
1620 it is already running. Default is ON.
1622 editing on/off: Enables EMACS style command line editing
1623 of input. Previous lines can be recalled with
1624 control-P, the current line can be edited with control-B,
1625 you can search for commands with control-R, etc.
1628 history filename NAME: NAME is where the gdb command history
1629 will be stored. The default is .gdb_history,
1630 or the value of the environment variable
1633 history size N: The size, in commands, of the command history. The
1634 default is 256, or the value of the environment variable
1637 history save on/off: If this value is set to ON, the history file will
1638 be saved after exiting gdb. If set to OFF, the
1639 file will not be saved. The default is OFF.
1641 history expansion on/off: If this value is set to ON, then csh-like
1642 history expansion will be performed on
1643 command line input. The default is OFF.
1645 radix N: Sets the default radix for input and output. It can be set
1646 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1647 in the current radix, so "set radix 10" is always a no-op.
1649 height N: This integer value is the number of lines on a page. Default
1650 is 24, the current `stty rows'' setting, or the ``li#''
1651 setting from the termcap entry matching the environment
1654 width N: This integer value is the number of characters on a line.
1655 Default is 80, the current `stty cols'' setting, or the ``co#''
1656 setting from the termcap entry matching the environment
1659 Note: ``set screensize'' is obsolete. Use ``set height'' and
1660 ``set width'' instead.
1662 print address on/off: Print memory addresses in various command displays,
1663 such as stack traces and structure values. Gdb looks
1664 more ``symbolic'' if you turn this off; it looks more
1665 ``machine level'' with it on. Default is ON.
1667 print array on/off: Prettyprint arrays. New convenient format! Default
1670 print demangle on/off: Print C++ symbols in "source" form if on,
1673 print asm-demangle on/off: Same, for assembler level printouts
1676 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1679 * Support for Epoch Environment.
1681 The epoch environment is a version of Emacs v18 with windowing. One
1682 new command, ``inspect'', is identical to ``print'', except that if you
1683 are running in the epoch environment, the value is printed in its own
1687 * Support for Shared Libraries
1689 GDB can now debug programs and core files that use SunOS shared libraries.
1690 Symbols from a shared library cannot be referenced
1691 before the shared library has been linked with the program (this
1692 happens after you type ``run'' and before the function main() is entered).
1693 At any time after this linking (including when examining core files
1694 from dynamically linked programs), gdb reads the symbols from each
1695 shared library when you type the ``sharedlibrary'' command.
1696 It can be abbreviated ``share''.
1698 sharedlibrary REGEXP: Load shared object library symbols for files
1699 matching a unix regular expression. No argument
1700 indicates to load symbols for all shared libraries.
1702 info sharedlibrary: Status of loaded shared libraries.
1707 A watchpoint stops execution of a program whenever the value of an
1708 expression changes. Checking for this slows down execution
1709 tremendously whenever you are in the scope of the expression, but is
1710 quite useful for catching tough ``bit-spreader'' or pointer misuse
1711 problems. Some machines such as the 386 have hardware for doing this
1712 more quickly, and future versions of gdb will use this hardware.
1714 watch EXP: Set a watchpoint (breakpoint) for an expression.
1716 info watchpoints: Information about your watchpoints.
1718 delete N: Deletes watchpoint number N (same as breakpoints).
1719 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1720 enable N: Re-enables watchpoint number N (same as breakpoints).
1723 * C++ multiple inheritance
1725 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1728 * C++ exception handling
1730 Gdb now supports limited C++ exception handling. Besides the existing
1731 ability to breakpoint on an exception handler, gdb can breakpoint on
1732 the raising of an exception (before the stack is peeled back to the
1735 catch FOO: If there is a FOO exception handler in the dynamic scope,
1736 set a breakpoint to catch exceptions which may be raised there.
1737 Multiple exceptions (``catch foo bar baz'') may be caught.
1739 info catch: Lists all exceptions which may be caught in the
1740 current stack frame.
1743 * Minor command changes
1745 The command ``call func (arg, arg, ...)'' now acts like the print
1746 command, except it does not print or save a value if the function's result
1747 is void. This is similar to dbx usage.
1749 The ``up'' and ``down'' commands now always print the frame they end up
1750 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1751 frames without printing.
1753 * New directory command
1755 'dir' now adds directories to the FRONT of the source search path.
1756 The path starts off empty. Source files that contain debug information
1757 about the directory in which they were compiled can be found even
1758 with an empty path; Sun CC and GCC include this information. If GDB can't
1759 find your source file in the current directory, type "dir .".
1761 * Configuring GDB for compilation
1763 For normal use, type ``./configure host''. See README or gdb.texinfo
1766 GDB now handles cross debugging. If you are remotely debugging between
1767 two different machines, type ``./configure host -target=targ''.
1768 Host is the machine where GDB will run; targ is the machine
1769 where the program that you are debugging will run.