1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes in GDB 5.0:
6 * Improved support for debugging FP programs on x86 targets
8 Unified and much-improved support for debugging floating-point
9 programs on all x86 targets. In particular, ``info float'' now
10 displays the FP registers in the same format on all x86 targets, with
11 greater level of detail.
13 * Improvements and bugfixes in hardware-assisted watchpoints
15 It is now possible to watch array elements, struct members, and
16 bitfields with hardware-assisted watchpoints. Data-read watchpoints
17 on x86 targets no longer erroneously trigger when the address is
20 * Improvements in the native DJGPP version of GDB
22 The distribution now includes all the scripts and auxiliary files
23 necessary to build the native DJGPP version on MS-DOS/MS-Windows
24 machines ``out of the box''.
26 The DJGPP version can now debug programs that use signals. It is
27 possible to catch signals that happened in the debuggee, deliver
28 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
29 would kill the program being debugged.) Programs that hook hardware
30 interrupts (keyboard, timer, etc.) can also be debugged.
32 It is now possible to debug DJGPP programs that redirect their
33 standard handles or switch them to raw (as opposed to cooked) mode, or
34 even close them. The command ``run < foo > bar'' works as expected,
35 and ``info terminal'' reports useful information about the debuggee's
36 terminal, including raw/cooked mode, redirection, etc.
38 The DJGPP version now uses termios functions for console I/O, which
39 enables debugging graphics programs. Interrupting GDB with Ctrl-C
42 DOS-style file names with drive letters are now fully supported by
45 It is now possible to debug DJGPP programs that switch their working
46 directory. It is also possible to rerun the debuggee any number of
47 times without restarting GDB; thus, you can use the same setup,
48 breakpoints, etc. for many debugging sessions.
50 * New native configurations
52 ARM GNU/Linux arm*-*-linux*
53 PowerPC GNU/Linux powerpc-*-linux*
57 Motorola MCore mcore-*-*
58 x86 VxWorks i[3456]86-*-vxworks*
59 PowerPC VxWorks powerpc-*-vxworks*
60 TI TMS320C80 tic80-*-*
62 * OBSOLETE configurations
64 Altos 3068 m68*-altos-*
67 ARM RISCix arm-*-* (as host)
70 Configurations that have been declared obsolete will be commented out,
71 but the code will be left in place. If there is no activity to revive
72 these configurations before the next release of GDB, the sources will
73 be permanently REMOVED.
75 * New features for SVR4
77 On SVR4 native platforms (such as Solaris), if you attach to a process
78 without first loading a symbol file, GDB will now attempt to locate and
79 load symbols from the running process's executable file.
81 * Many C++ enhancements
83 C++ support has been greatly improved. Overload resolution now works properly
84 in almost all cases. RTTI support is on the way.
86 * Remote targets can connect to a sub-program
88 A popen(3) style serial-device has been added. This device starts a
89 sub-process (such as a stand-alone simulator) and then communicates
90 with that. The sub-program to run is specified using the syntax
91 ``|<program> <args>'' vis:
93 (gdb) set remotedebug 1
94 (gdb) target extended-remote |mn10300-elf-sim program-args
96 * MIPS 64 remote protocol
98 A long standing bug in the mips64 remote protocol where by GDB
99 expected certain 32 bit registers (ex SR) to be transfered as 32
100 instead of 64 bits has been fixed.
102 The command ``set remote-mips64-transfers-32bit-regs on'' has been
103 added to provide backward compatibility with older versions of GDB.
105 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
107 The command ``set remotebinarydownload'' command has been replaced by
108 ``set remote X-packet''. Other commands in ``set remote'' family
109 include ``set remote P-packet''.
111 * Breakpoint commands accept ranges.
113 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
114 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
115 ``tracepoint passcount'' also accepts a range of tracepoints.
117 * ``apropos'' command added.
119 The ``apropos'' command searches through command names and
120 documentation strings, printing out matches, making it much easier to
121 try to find a command that does what you are looking for.
125 A new machine oriented interface (MI) has been added to GDB. This
126 interface is designed for debug environments running GDB as a separate
127 process. This is part of the long term libGDB project. See
128 gdb/mi/gdbmi.texinfo for further information. It can be enabled by
131 .../configure --enable-gdbmi
133 *** Changes in GDB-4.18:
135 * New native configurations
137 HP-UX 10.20 hppa*-*-hpux10.20
138 HP-UX 11.x hppa*-*-hpux11.0*
139 M68K Linux m68*-*-linux*
143 Fujitsu FR30 fr30-*-elf*
144 Intel StrongARM strongarm-*-*
145 Mitsubishi D30V d30v-*-*
147 * OBSOLETE configurations
149 Gould PowerNode, NP1 np1-*-*, pn-*-*
151 Configurations that have been declared obsolete will be commented out,
152 but the code will be left in place. If there is no activity to revive
153 these configurations before the next release of GDB, the sources will
154 be permanently REMOVED.
158 As a compatibility experiment, GDB's source files buildsym.h and
159 buildsym.c have been converted to pure standard C, no longer
160 containing any K&R compatibility code. We believe that all systems in
161 use today either come with a standard C compiler, or have a GCC port
162 available. If this is not true, please report the affected
163 configuration to bug-gdb@gnu.org immediately. See the README file for
164 information about getting a standard C compiler if you don't have one
169 GDB now uses readline 2.2.
171 * set extension-language
173 You can now control the mapping between filename extensions and source
174 languages by using the `set extension-language' command. For instance,
175 you can ask GDB to treat .c files as C++ by saying
176 set extension-language .c c++
177 The command `info extensions' lists all of the recognized extensions
178 and their associated languages.
180 * Setting processor type for PowerPC and RS/6000
182 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
183 you can use the `set processor' command to specify what variant of the
184 PowerPC family you are debugging. The command
188 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
189 following PowerPC and RS6000 variants:
191 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
192 rs6000 IBM RS6000 ("POWER") architecture, user-level view
194 403GC IBM PowerPC 403GC
195 505 Motorola PowerPC 505
196 860 Motorola PowerPC 860 or 850
197 601 Motorola PowerPC 601
198 602 Motorola PowerPC 602
199 603 Motorola/IBM PowerPC 603 or 603e
200 604 Motorola PowerPC 604 or 604e
201 750 Motorola/IBM PowerPC 750 or 750
203 At the moment, this command just tells GDB what to name the
204 special-purpose processor registers. Since almost all the affected
205 registers are inaccessible to user-level programs, this command is
206 only useful for remote debugging in its present form.
210 Thanks to a major code donation from Hewlett-Packard, GDB now has much
211 more extensive support for HP-UX. Added features include shared
212 library support, kernel threads and hardware watchpoints for 11.00,
213 support for HP's ANSI C and C++ compilers, and a compatibility mode
214 for xdb and dbx commands.
218 HP's donation includes the new concept of catchpoints, which is a
219 generalization of the old catch command. On HP-UX, it is now possible
220 to catch exec, fork, and vfork, as well as library loading.
222 This means that the existing catch command has changed; its first
223 argument now specifies the type of catch to be set up. See the
224 output of "help catch" for a list of catchpoint types.
226 * Debugging across forks
228 On HP-UX, you can choose which process to debug when a fork() happens
233 HP has donated a curses-based terminal user interface (TUI). To get
234 it, build with --enable-tui. Although this can be enabled for any
235 configuration, at present it only works for native HP debugging.
237 * GDB remote protocol additions
239 A new protocol packet 'X' that writes binary data is now available.
240 Default behavior is to try 'X', then drop back to 'M' if the stub
241 fails to respond. The settable variable `remotebinarydownload'
242 allows explicit control over the use of 'X'.
244 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
245 full 64-bit address. The command
247 set remoteaddresssize 32
249 can be used to revert to the old behaviour. For existing remote stubs
250 the change should not be noticed, as the additional address information
253 In order to assist in debugging stubs, you may use the maintenance
254 command `packet' to send any text string to the stub. For instance,
256 maint packet heythere
258 sends the packet "$heythere#<checksum>". Note that it is very easy to
259 disrupt a debugging session by sending the wrong packet at the wrong
262 The compare-sections command allows you to compare section data on the
263 target to what is in the executable file without uploading or
264 downloading, by comparing CRC checksums.
266 * Tracing can collect general expressions
268 You may now collect general expressions at tracepoints. This requires
269 further additions to the target-side stub; see tracepoint.c and
270 doc/agentexpr.texi for further details.
272 * mask-address variable for Mips
274 For Mips targets, you may control the zeroing of the upper 32 bits of
275 a 64-bit address by entering `set mask-address on'. This is mainly
276 of interest to users of embedded R4xxx and R5xxx processors.
278 * Higher serial baud rates
280 GDB's serial code now allows you to specify baud rates 57600, 115200,
281 230400, and 460800 baud. (Note that your host system may not be able
282 to achieve all of these rates.)
286 The i960 configuration now includes an initial implementation of a
287 builtin simulator, contributed by Jim Wilson.
290 *** Changes in GDB-4.17:
292 * New native configurations
294 Alpha GNU/Linux alpha*-*-linux*
295 Unixware 2.x i[3456]86-unixware2*
296 Irix 6.x mips*-sgi-irix6*
297 PowerPC GNU/Linux powerpc-*-linux*
298 PowerPC Solaris powerpcle-*-solaris*
299 Sparc GNU/Linux sparc-*-linux*
300 Motorola sysV68 R3V7.1 m68k-motorola-sysv
304 Argonaut Risc Chip (ARC) arc-*-*
305 Hitachi H8/300S h8300*-*-*
306 Matsushita MN10200 w/simulator mn10200-*-*
307 Matsushita MN10300 w/simulator mn10300-*-*
308 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
309 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
310 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
311 Mitsubishi D10V w/simulator d10v-*-*
312 Mitsubishi M32R/D w/simulator m32r-*-elf*
313 Tsqware Sparclet sparclet-*-*
314 NEC V850 w/simulator v850-*-*
316 * New debugging protocols
318 ARM with RDI protocol arm*-*-*
319 M68K with dBUG monitor m68*-*-{aout,coff,elf}
320 DDB and LSI variants of PMON protocol mips*-*-*
321 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
322 PowerPC with SDS protocol powerpc{,le}-*-eabi
323 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
327 All configurations can now understand and use the DWARF 2 debugging
328 format. The choice is automatic, if the symbol file contains DWARF 2
333 GDB now includes basic Java language support. This support is
334 only useful with Java compilers that produce native machine code.
336 * solib-absolute-prefix and solib-search-path
338 For SunOS and SVR4 shared libraries, you may now set the prefix for
339 loading absolute shared library symbol files, and the search path for
340 locating non-absolute shared library symbol files.
342 * Live range splitting
344 GDB can now effectively debug code for which GCC has performed live
345 range splitting as part of its optimization. See gdb/doc/LRS for
346 more details on the expected format of the stabs information.
350 GDB's support for the GNU Hurd, including thread debugging, has been
351 updated to work with current versions of the Hurd.
355 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
356 instruction set. ARM GDB automatically detects when Thumb
357 instructions are in use, and adjusts disassembly and backtracing
362 GDB's MIPS target configurations now handle the MIP16 16-bit
367 GDB now includes support for overlays; if an executable has been
368 linked such that multiple sections are based at the same address, GDB
369 will decide which section to use for symbolic info. You can choose to
370 control the decision manually, using overlay commands, or implement
371 additional target-side support and use "overlay load-target" to bring
372 in the overlay mapping. Do "help overlay" for more detail.
376 The command "info symbol <address>" displays information about
377 the symbol at the specified address.
381 The standard remote protocol now includes an extension that allows
382 asynchronous collection and display of trace data. This requires
383 extensive support in the target-side debugging stub. Tracing mode
384 includes a new interaction mode in GDB and new commands: see the
385 file tracepoint.c for more details.
389 Configurations for embedded MIPS now include a simulator contributed
390 by Cygnus Solutions. The simulator supports the instruction sets
391 of most MIPS variants.
395 Sparc configurations may now include the ERC32 simulator contributed
396 by the European Space Agency. The simulator is not built into
397 Sparc targets by default; configure with --enable-sim to include it.
401 For target configurations that may include multiple variants of a
402 basic architecture (such as MIPS and SH), you may now set the
403 architecture explicitly. "set arch" sets, "info arch" lists
404 the possible architectures.
406 *** Changes in GDB-4.16:
408 * New native configurations
410 Windows 95, x86 Windows NT i[345]86-*-cygwin32
411 M68K NetBSD m68k-*-netbsd*
412 PowerPC AIX 4.x powerpc-*-aix*
413 PowerPC MacOS powerpc-*-macos*
414 PowerPC Windows NT powerpcle-*-cygwin32
415 RS/6000 AIX 4.x rs6000-*-aix4*
419 ARM with RDP protocol arm-*-*
420 I960 with MON960 i960-*-coff
421 MIPS VxWorks mips*-*-vxworks*
422 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
423 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
425 Matra Sparclet sparclet-*-*
429 The powerpc-eabi configuration now includes the PSIM simulator,
430 contributed by Andrew Cagney, with assistance from Mike Meissner.
431 PSIM is a very elaborate model of the PowerPC, including not only
432 basic instruction set execution, but also details of execution unit
433 performance and I/O hardware. See sim/ppc/README for more details.
437 GDB now works with Solaris 2.5.
439 * Windows 95/NT native
441 GDB will now work as a native debugger on Windows 95 and Windows NT.
442 To build it from source, you must use the "gnu-win32" environment,
443 which uses a DLL to emulate enough of Unix to run the GNU tools.
444 Further information, binaries, and sources are available at
445 ftp.cygnus.com, under pub/gnu-win32.
447 * dont-repeat command
449 If a user-defined command includes the command `dont-repeat', then the
450 command will not be repeated if the user just types return. This is
451 useful if the command is time-consuming to run, so that accidental
452 extra keystrokes don't run the same command many times.
454 * Send break instead of ^C
456 The standard remote protocol now includes an option to send a break
457 rather than a ^C to the target in order to interrupt it. By default,
458 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
460 * Remote protocol timeout
462 The standard remote protocol includes a new variable `remotetimeout'
463 that allows you to set the number of seconds before GDB gives up trying
464 to read from the target. The default value is 2.
466 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
468 By default GDB will automatically keep track of objects as they are
469 loaded and unloaded by the dynamic linker. By using the command `set
470 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
471 when shared library events occur, thus allowing you to set breakpoints
472 in shared libraries which are explicitly loaded by the inferior.
474 Note this feature does not work on hpux8. On hpux9 you must link
475 /usr/lib/end.o into your program. This feature should work
476 automatically on hpux10.
478 * Irix 5.x hardware watchpoint support
480 Irix 5 configurations now support the use of hardware watchpoints.
482 * Mips protocol "SYN garbage limit"
484 When debugging a Mips target using the `target mips' protocol, you
485 may set the number of characters that GDB will ignore by setting
486 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
487 every character. The default value is 1050.
489 * Recording and replaying remote debug sessions
491 If you set `remotelogfile' to the name of a file, gdb will write to it
492 a recording of a remote debug session. This recording may then be
493 replayed back to gdb using "gdbreplay". See gdbserver/README for
494 details. This is useful when you have a problem with GDB while doing
495 remote debugging; you can make a recording of the session and send it
496 to someone else, who can then recreate the problem.
498 * Speedups for remote debugging
500 GDB includes speedups for downloading and stepping MIPS systems using
501 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
502 and more efficient S-record downloading.
504 * Memory use reductions and statistics collection
506 GDB now uses less memory and reports statistics about memory usage.
507 Try the `maint print statistics' command, for example.
509 *** Changes in GDB-4.15:
513 The symbol reader for AIX GDB now uses partial symbol tables. This
514 can greatly improve startup time, especially for large executables.
516 * Remote targets use caching
518 Remote targets now use a data cache to speed up communication with the
519 remote side. The data cache could lead to incorrect results because
520 it doesn't know about volatile variables, thus making it impossible to
521 debug targets which use memory mapped I/O devices. `set remotecache
522 off' turns the the data cache off.
524 * Remote targets may have threads
526 The standard remote protocol now includes support for multiple threads
527 in the target system, using new protocol commands 'H' and 'T'. See
528 gdb/remote.c for details.
532 If GDB is configured with `--enable-netrom', then it will include
533 support for the NetROM ROM emulator from XLNT Designs. The NetROM
534 acts as though it is a bank of ROM on the target board, but you can
535 write into it over the network. GDB's support consists only of
536 support for fast loading into the emulated ROM; to debug, you must use
537 another protocol, such as standard remote protocol. The usual
538 sequence is something like
540 target nrom <netrom-hostname>
542 target remote <netrom-hostname>:1235
546 GDB now includes support for the Apple Macintosh, as a host only. It
547 may be run as either an MPW tool or as a standalone application, and
548 it can debug through the serial port. All the usual GDB commands are
549 available, but to the target command, you must supply "serial" as the
550 device type instead of "/dev/ttyXX". See mpw-README in the main
551 directory for more information on how to build. The MPW configuration
552 scripts */mpw-config.in support only a few targets, and only the
553 mips-idt-ecoff target has been tested.
557 GDB configuration now uses autoconf. This is not user-visible,
558 but does simplify configuration and building.
562 GDB now supports hpux10.
564 *** Changes in GDB-4.14:
566 * New native configurations
568 x86 FreeBSD i[345]86-*-freebsd
569 x86 NetBSD i[345]86-*-netbsd
570 NS32k NetBSD ns32k-*-netbsd
571 Sparc NetBSD sparc-*-netbsd
575 A29K VxWorks a29k-*-vxworks
576 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
577 CPU32 EST-300 emulator m68*-*-est*
578 PowerPC ELF powerpc-*-elf
581 * Alpha OSF/1 support for procfs
583 GDB now supports procfs under OSF/1-2.x and higher, which makes it
584 possible to attach to running processes. As the mounting of the /proc
585 filesystem is optional on the Alpha, GDB automatically determines
586 the availability of /proc during startup. This can lead to problems
587 if /proc is unmounted after GDB has been started.
589 * Arguments to user-defined commands
591 User commands may accept up to 10 arguments separated by whitespace.
592 Arguments are accessed within the user command via $arg0..$arg9. A
595 print $arg0 + $arg1 + $arg2
597 To execute the command use:
600 Defines the command "adder" which prints the sum of its three arguments.
601 Note the arguments are text substitutions, so they may reference variables,
602 use complex expressions, or even perform inferior function calls.
604 * New `if' and `while' commands
606 This makes it possible to write more sophisticated user-defined
607 commands. Both commands take a single argument, which is the
608 expression to evaluate, and must be followed by the commands to
609 execute, one per line, if the expression is nonzero, the list being
610 terminated by the word `end'. The `if' command list may include an
611 `else' word, which causes the following commands to be executed only
612 if the expression is zero.
614 * Fortran source language mode
616 GDB now includes partial support for Fortran 77. It will recognize
617 Fortran programs and can evaluate a subset of Fortran expressions, but
618 variables and functions may not be handled correctly. GDB will work
619 with G77, but does not yet know much about symbols emitted by other
622 * Better HPUX support
624 Most debugging facilities now work on dynamic executables for HPPAs
625 running hpux9 or later. You can attach to running dynamically linked
626 processes, but by default the dynamic libraries will be read-only, so
627 for instance you won't be able to put breakpoints in them. To change
628 that behavior do the following before running the program:
634 This will cause the libraries to be mapped private and read-write.
635 To revert to the normal behavior, do this:
641 You cannot set breakpoints or examine data in the library until after
642 the library is loaded if the function/data symbols do not have
645 GDB can now also read debug symbols produced by the HP C compiler on
646 HPPAs (sorry, no C++, Fortran or 68k support).
648 * Target byte order now dynamically selectable
650 You can choose which byte order to use with a target system, via the
651 commands "set endian big" and "set endian little", and you can see the
652 current setting by using "show endian". You can also give the command
653 "set endian auto", in which case GDB will use the byte order
654 associated with the executable. Currently, only embedded MIPS
655 configurations support dynamic selection of target byte order.
657 * New DOS host serial code
659 This version uses DPMI interrupts to handle buffered I/O, so you
660 no longer need to run asynctsr when debugging boards connected to
663 *** Changes in GDB-4.13:
665 * New "complete" command
667 This lists all the possible completions for the rest of the line, if it
668 were to be given as a command itself. This is intended for use by emacs.
670 * Trailing space optional in prompt
672 "set prompt" no longer adds a space for you after the prompt you set. This
673 allows you to set a prompt which ends in a space or one that does not.
675 * Breakpoint hit counts
677 "info break" now displays a count of the number of times the breakpoint
678 has been hit. This is especially useful in conjunction with "ignore"; you
679 can ignore a large number of breakpoint hits, look at the breakpoint info
680 to see how many times the breakpoint was hit, then run again, ignoring one
681 less than that number, and this will get you quickly to the last hit of
684 * Ability to stop printing at NULL character
686 "set print null-stop" will cause GDB to stop printing the characters of
687 an array when the first NULL is encountered. This is useful when large
688 arrays actually contain only short strings.
690 * Shared library breakpoints
692 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
693 breakpoints in shared libraries before the executable is run.
695 * Hardware watchpoints
697 There is a new hardware breakpoint for the watch command for sparclite
698 targets. See gdb/sparclite/hw_breakpoint.note.
700 Hardware watchpoints are also now supported under Linux.
704 Annotations have been added. These are for use with graphical interfaces,
705 and are still experimental. Currently only gdba.el uses these.
707 * Improved Irix 5 support
709 GDB now works properly with Irix 5.2.
711 * Improved HPPA support
713 GDB now works properly with the latest GCC and GAS.
715 * New native configurations
717 Sequent PTX4 i[34]86-sequent-ptx4
718 HPPA running OSF/1 hppa*-*-osf*
719 Atari TT running SVR4 m68*-*-sysv4*
720 RS/6000 LynxOS rs6000-*-lynxos*
724 OS/9000 i[34]86-*-os9k
725 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
728 * Hitachi SH7000 and E7000-PC ICE support
730 There is now support for communicating with the Hitachi E7000-PC ICE.
731 This is available automatically when GDB is configured for the SH.
735 As usual, a variety of small fixes and improvements, both generic
736 and configuration-specific. See the ChangeLog for more detail.
738 *** Changes in GDB-4.12:
740 * Irix 5 is now supported
744 GDB-4.12 on the HPPA has a number of changes which make it unable
745 to debug the output from the currently released versions of GCC and
746 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
747 of GCC and GAS, versions of these tools designed to work with GDB-4.12
748 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
751 *** Changes in GDB-4.11:
753 * User visible changes:
757 The "set remotedebug" option is now consistent between the mips remote
758 target, remote targets using the gdb-specific protocol, UDI (AMD's
759 debug protocol for the 29k) and the 88k bug monitor. It is now an
760 integer specifying a debug level (normally 0 or 1, but 2 means more
761 debugging info for the mips target).
763 * DEC Alpha native support
765 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
766 debug info, but GDB works fairly well with the DEC compiler and should
767 work with a future GCC release. See the README file for a few
768 Alpha-specific notes.
770 * Preliminary thread implementation
772 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
774 * LynxOS native and target support for 386
776 This release has been hosted on LynxOS 2.2, and also can be configured
777 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
780 * Improvements in C++ mangling/demangling.
782 This release has much better g++ debugging, specifically in name
783 mangling/demangling, virtual function calls, print virtual table,
784 call methods, ...etc.
786 *** Changes in GDB-4.10:
788 * User visible changes:
790 Remote debugging using the GDB-specific (`target remote') protocol now
791 supports the `load' command. This is only useful if you have some
792 other way of getting the stub to the target system, and you can put it
793 somewhere in memory where it won't get clobbered by the download.
795 Filename completion now works.
797 When run under emacs mode, the "info line" command now causes the
798 arrow to point to the line specified. Also, "info line" prints
799 addresses in symbolic form (as well as hex).
801 All vxworks based targets now support a user settable option, called
802 vxworks-timeout. This option represents the number of seconds gdb
803 should wait for responses to rpc's. You might want to use this if
804 your vxworks target is, perhaps, a slow software simulator or happens
805 to be on the far side of a thin network line.
809 This release contains support for using a DEC alpha as a GDB host for
810 cross debugging. Native alpha debugging is not supported yet.
813 *** Changes in GDB-4.9:
817 This is the first GDB release which is accompanied by a matching testsuite.
818 The testsuite requires installation of dejagnu, which should be available
819 via ftp from most sites that carry GNU software.
823 'Cfront' style demangling has had its name changed to 'ARM' style, to
824 emphasize that it was written from the specifications in the C++ Annotated
825 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
826 disclaimers, it still generated too much confusion with users attempting to
827 use gdb with AT&T cfront.
831 GDB now uses a standard remote interface to a simulator library.
832 So far, the library contains simulators for the Zilog Z8001/2, the
833 Hitachi H8/300, H8/500 and Super-H.
835 * New targets supported
837 H8/300 simulator h8300-hitachi-hms or h8300hms
838 H8/500 simulator h8500-hitachi-hms or h8500hms
839 SH simulator sh-hitachi-hms or sh
840 Z8000 simulator z8k-zilog-none or z8ksim
841 IDT MIPS board over serial line mips-idt-ecoff
843 Cross-debugging to GO32 targets is supported. It requires a custom
844 version of the i386-stub.c module which is integrated with the
845 GO32 memory extender.
847 * New remote protocols
849 MIPS remote debugging protocol.
851 * New source languages supported
853 This version includes preliminary support for Chill, a Pascal like language
854 used by telecommunications companies. Chill support is also being integrated
855 into the GNU compiler, but we don't know when it will be publically available.
858 *** Changes in GDB-4.8:
860 * HP Precision Architecture supported
862 GDB now supports HP PA-RISC machines running HPUX. A preliminary
863 version of this support was available as a set of patches from the
864 University of Utah. GDB does not support debugging of programs
865 compiled with the HP compiler, because HP will not document their file
866 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
867 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
869 Many problems in the preliminary version have been fixed.
871 * Faster and better demangling
873 We have improved template demangling and fixed numerous bugs in the GNU style
874 demangler. It can now handle type modifiers such as `static' or `const'. Wide
875 character types (wchar_t) are now supported. Demangling of each symbol is now
876 only done once, and is cached when the symbol table for a file is read in.
877 This results in a small increase in memory usage for C programs, a moderate
878 increase in memory usage for C++ programs, and a fantastic speedup in
881 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
882 from the specifications in the Annotated Reference Manual, which AT&T's
883 compiler does not actually implement.
885 * G++ multiple inheritance compiler problem
887 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
888 inheritance lattices was reworked to properly discover ambiguities. We
889 recently found an example which causes this new algorithm to fail in a
890 very subtle way, producing bad debug information for those classes.
891 The file 'gcc.patch' (in this directory) can be applied to gcc to
892 circumvent the problem. A future GCC release will contain a complete
895 The previous G++ debug info problem (mentioned below for the gdb-4.7
896 release) is fixed in gcc version 2.3.2.
898 * Improved configure script
900 The `configure' script will now attempt to guess your system type if
901 you don't supply a host system type. The old scheme of supplying a
902 host system triplet is preferable over using this. All the magic is
903 done in the new `config.guess' script. Examine it for details.
905 We have also brought our configure script much more in line with the FSF's
906 version. It now supports the --with-xxx options. In particular,
907 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
908 The resulting GDB will not be able to read arbitrary object file formats --
909 only the format ``expected'' to be used on the configured target system.
910 We hope to make this the default in a future release.
912 * Documentation improvements
914 There's new internal documentation on how to modify GDB, and how to
915 produce clean changes to the code. We implore people to read it
916 before submitting changes.
918 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
919 M4 macros. The new texinfo.tex is provided in this release. Pre-built
920 `info' files are also provided. To build `info' files from scratch,
921 you will need the latest `makeinfo' release, which will be available in
922 a future texinfo-X.Y release.
924 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
925 We're not sure exactly which versions have this problem, but it has
926 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
927 or better. If that isn't possible, there is a patch in
928 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
933 GDB now supports array constants that can be used in expressions typed in by
934 the user. The syntax is `{element, element, ...}'. Ie: you can now type
935 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
938 The new directory `gdb/sparclite' contains a program that demonstrates
939 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
941 * New native hosts supported
943 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
944 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
946 * New targets supported
948 AMD 29k family via UDI a29k-amd-udi or udi29k
950 * New file formats supported
952 BFD now supports reading HP/PA-RISC executables (SOM file format?),
953 HPUX core files, and SCO 3.2v2 core files.
957 Attaching to processes now works again; thanks for the many bug reports.
959 We have also stomped on a bunch of core dumps caused by
960 printf_filtered("%s") problems.
962 We eliminated a copyright problem on the rpc and ptrace header files
963 for VxWorks, which was discovered at the last minute during the 4.7
964 release. You should now be able to build a VxWorks GDB.
966 You can now interrupt gdb while an attached process is running. This
967 will cause the attached process to stop, and give control back to GDB.
969 We fixed problems caused by using too many file descriptors
970 for reading symbols from object files and libraries. This was
971 especially a problem for programs that used many (~100) shared
974 The `step' command now only enters a subroutine if there is line number
975 information for the subroutine. Otherwise it acts like the `next'
976 command. Previously, `step' would enter subroutines if there was
977 any debugging information about the routine. This avoids problems
978 when using `cc -g1' on MIPS machines.
980 * Internal improvements
982 GDB's internal interfaces have been improved to make it easier to support
983 debugging of multiple languages in the future.
985 GDB now uses a common structure for symbol information internally.
986 Minimal symbols (derived from linkage symbols in object files), partial
987 symbols (from a quick scan of debug information), and full symbols
988 contain a common subset of information, making it easier to write
989 shared code that handles any of them.
991 * New command line options
993 We now accept --silent as an alias for --quiet.
997 The memory-mapped-malloc library is now licensed under the GNU Library
998 General Public License.
1000 *** Changes in GDB-4.7:
1002 * Host/native/target split
1004 GDB has had some major internal surgery to untangle the support for
1005 hosts and remote targets. Now, when you configure GDB for a remote
1006 target, it will no longer load in all of the support for debugging
1007 local programs on the host. When fully completed and tested, this will
1008 ensure that arbitrary host/target combinations are possible.
1010 The primary conceptual shift is to separate the non-portable code in
1011 GDB into three categories. Host specific code is required any time GDB
1012 is compiled on that host, regardless of the target. Target specific
1013 code relates to the peculiarities of the target, but can be compiled on
1014 any host. Native specific code is everything else: it can only be
1015 built when the host and target are the same system. Child process
1016 handling and core file support are two common `native' examples.
1018 GDB's use of /proc for controlling Unix child processes is now cleaner.
1019 It has been split out into a single module under the `target_ops' vector,
1020 plus two native-dependent functions for each system that uses /proc.
1022 * New hosts supported
1024 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
1025 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1026 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
1028 * New targets supported
1030 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
1031 68030 and CPU32 m68030-*-*, m68332-*-*
1033 * New native hosts supported
1035 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
1036 (386bsd is not well tested yet)
1037 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
1039 * New file formats supported
1041 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
1042 supports reading of `a.out.adobe' object files, which are an a.out
1043 format extended with minimal information about multiple sections.
1047 `show copying' is the same as the old `info copying'.
1048 `show warranty' is the same as `info warrantee'.
1049 These were renamed for consistency. The old commands continue to work.
1051 `info handle' is a new alias for `info signals'.
1053 You can now define pre-command hooks, which attach arbitrary command
1054 scripts to any command. The commands in the hook will be executed
1055 prior to the user's command. You can also create a hook which will be
1056 executed whenever the program stops. See gdb.texinfo.
1060 We now deal with Cfront style name mangling, and can even extract type
1061 info from mangled symbols. GDB can automatically figure out which
1062 symbol mangling style your C++ compiler uses.
1064 Calling of methods and virtual functions has been improved as well.
1068 The crash that occured when debugging Sun Ansi-C compiled binaries is
1069 fixed. This was due to mishandling of the extra N_SO stabs output
1072 We also finally got Ultrix 4.2 running in house, and fixed core file
1073 support, with help from a dozen people on the net.
1075 John M. Farrell discovered that the reason that single-stepping was so
1076 slow on all of the Mips based platforms (primarily SGI and DEC) was
1077 that we were trying to demangle and lookup a symbol used for internal
1078 purposes on every instruction that was being stepped through. Changing
1079 the name of that symbol so that it couldn't be mistaken for a C++
1080 mangled symbol sped things up a great deal.
1082 Rich Pixley sped up symbol lookups in general by getting much smarter
1083 about when C++ symbol mangling is necessary. This should make symbol
1084 completion (TAB on the command line) much faster. It's not as fast as
1085 we'd like, but it's significantly faster than gdb-4.6.
1089 A new user controllable variable 'call_scratch_address' can
1090 specify the location of a scratch area to be used when GDB
1091 calls a function in the target. This is necessary because the
1092 usual method of putting the scratch area on the stack does not work
1093 in systems that have separate instruction and data spaces.
1095 We integrated changes to support the 29k UDI (Universal Debugger
1096 Interface), but discovered at the last minute that we didn't have all
1097 of the appropriate copyright paperwork. We are working with AMD to
1098 resolve this, and hope to have it available soon.
1102 We have sped up the remote serial line protocol, especially for targets
1103 with lots of registers. It now supports a new `expedited status' ('T')
1104 message which can be used in place of the existing 'S' status message.
1105 This allows the remote stub to send only the registers that GDB
1106 needs to make a quick decision about single-stepping or conditional
1107 breakpoints, eliminating the need to fetch the entire register set for
1108 each instruction being stepped through.
1110 The GDB remote serial protocol now implements a write-through cache for
1111 registers, only re-reading the registers if the target has run.
1113 There is also a new remote serial stub for SPARC processors. You can
1114 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
1115 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
1116 processor with a serial port.
1120 Configure.in files have become much easier to read and modify. A new
1121 `table driven' format makes it more obvious what configurations are
1122 supported, and what files each one uses.
1126 There is a new opcodes library which will eventually contain all of the
1127 disassembly routines and opcode tables. At present, it only contains
1128 Sparc and Z8000 routines. This will allow the assembler, debugger, and
1129 disassembler (binutils/objdump) to share these routines.
1131 The libiberty library is now copylefted under the GNU Library General
1132 Public License. This allows more liberal use, and was done so libg++
1133 can use it. This makes no difference to GDB, since the Library License
1134 grants all the rights from the General Public License.
1138 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
1139 reference to the stabs symbol info used by the debugger. It is (as far
1140 as we know) the only published document on this fascinating topic. We
1141 encourage you to read it, compare it to the stabs information on your
1142 system, and send improvements on the document in general (to
1143 bug-gdb@prep.ai.mit.edu).
1145 And, of course, many bugs have been fixed.
1148 *** Changes in GDB-4.6:
1150 * Better support for C++ function names
1152 GDB now accepts as input the "demangled form" of C++ overloaded function
1153 names and member function names, and can do command completion on such names
1154 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
1155 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
1156 Make use of command completion, it is your friend.
1158 GDB also now accepts a variety of C++ mangled symbol formats. They are
1159 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
1160 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
1161 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
1162 for the list of formats.
1164 * G++ symbol mangling problem
1166 Recent versions of gcc have a bug in how they emit debugging information for
1167 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
1168 directory) can be applied to gcc to fix the problem. Alternatively, if you
1169 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
1170 usual symptom is difficulty with setting breakpoints on methods. GDB complains
1171 about the method being non-existent. (We believe that version 2.2.2 of GCC has
1174 * New 'maintenance' command
1176 All of the commands related to hacking GDB internals have been moved out of
1177 the main command set, and now live behind the 'maintenance' command. This
1178 can also be abbreviated as 'mt'. The following changes were made:
1180 dump-me -> maintenance dump-me
1181 info all-breakpoints -> maintenance info breakpoints
1182 printmsyms -> maintenance print msyms
1183 printobjfiles -> maintenance print objfiles
1184 printpsyms -> maintenance print psymbols
1185 printsyms -> maintenance print symbols
1187 The following commands are new:
1189 maintenance demangle Call internal GDB demangler routine to
1190 demangle a C++ link name and prints the result.
1191 maintenance print type Print a type chain for a given symbol
1193 * Change to .gdbinit file processing
1195 We now read the $HOME/.gdbinit file before processing the argv arguments
1196 (e.g. reading symbol files or core files). This allows global parameters to
1197 be set, which will apply during the symbol reading. The ./.gdbinit is still
1198 read after argv processing.
1200 * New hosts supported
1202 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
1204 Linux support i386-unknown-linux or linux
1206 We are also including code to support the HP/PA running BSD and HPUX. This
1207 is almost guaranteed not to work, as we didn't have time to test or build it
1208 for this release. We are including it so that the more adventurous (or
1209 masochistic) of you can play with it. We also had major problems with the
1210 fact that the compiler that we got from HP doesn't support the -g option.
1213 * New targets supported
1215 Hitachi H8/300 h8300-hitachi-hms or h8300hms
1217 * More smarts about finding #include files
1219 GDB now remembers the compilation directory for all include files, and for
1220 all files from which C is generated (like yacc and lex sources). This
1221 greatly improves GDB's ability to find yacc/lex sources, and include files,
1222 especially if you are debugging your program from a directory different from
1223 the one that contains your sources.
1225 We also fixed a bug which caused difficulty with listing and setting
1226 breakpoints in include files which contain C code. (In the past, you had to
1227 try twice in order to list an include file that you hadn't looked at before.)
1229 * Interesting infernals change
1231 GDB now deals with arbitrary numbers of sections, where the symbols for each
1232 section must be relocated relative to that section's landing place in the
1233 target's address space. This work was needed to support ELF with embedded
1234 stabs used by Solaris-2.0.
1236 * Bug fixes (of course!)
1238 There have been loads of fixes for the following things:
1239 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
1240 i960, stabs, DOS(GO32), procfs, etc...
1242 See the ChangeLog for details.
1244 *** Changes in GDB-4.5:
1246 * New machines supported (host and target)
1248 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
1250 SGI Irix-4.x mips-sgi-irix4 or iris4
1252 * New malloc package
1254 GDB now uses a new memory manager called mmalloc, based on gmalloc.
1255 Mmalloc is capable of handling mutiple heaps of memory. It is also
1256 capable of saving a heap to a file, and then mapping it back in later.
1257 This can be used to greatly speedup the startup of GDB by using a
1258 pre-parsed symbol table which lives in a mmalloc managed heap. For
1259 more details, please read mmalloc/mmalloc.texi.
1263 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
1264 'help info proc' for details.
1266 * MIPS ecoff symbol table format
1268 The code that reads MIPS symbol table format is now supported on all hosts.
1269 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
1272 * File name changes for MS-DOS
1274 Many files in the config directories have been renamed to make it easier to
1275 support GDB on MS-DOSe systems (which have very restrictive file name
1276 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
1277 environment) is close to working but has some remaining problems. Note
1278 that debugging of DOS programs is not supported, due to limitations
1279 in the ``operating system'', but it can be used to host cross-debugging.
1281 * Cross byte order fixes
1283 Many fixes have been made to support cross debugging of Sparc and MIPS
1284 targets from hosts whose byte order differs.
1286 * New -mapped and -readnow options
1288 If memory-mapped files are available on your system through the 'mmap'
1289 system call, you can use the -mapped option on the `file' or
1290 `symbol-file' commands to cause GDB to write the symbols from your
1291 program into a reusable file. If the program you are debugging is
1292 called `/path/fred', the mapped symbol file will be `./fred.syms'.
1293 Future GDB debugging sessions will notice the presence of this file,
1294 and will quickly map in symbol information from it, rather than reading
1295 the symbol table from the executable program. Using the '-mapped'
1296 option in a GDB `file' or `symbol-file' command has the same effect as
1297 starting GDB with the '-mapped' command-line option.
1299 You can cause GDB to read the entire symbol table immediately by using
1300 the '-readnow' option with any of the commands that load symbol table
1301 information (or on the GDB command line). This makes the command
1302 slower, but makes future operations faster.
1304 The -mapped and -readnow options are typically combined in order to
1305 build a `fred.syms' file that contains complete symbol information.
1306 A simple GDB invocation to do nothing but build a `.syms' file for future
1309 gdb -batch -nx -mapped -readnow programname
1311 The `.syms' file is specific to the host machine on which GDB is run.
1312 It holds an exact image of GDB's internal symbol table. It cannot be
1313 shared across multiple host platforms.
1315 * longjmp() handling
1317 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
1318 siglongjmp() without losing control. This feature has not yet been ported to
1319 all systems. It currently works on many 386 platforms, all MIPS-based
1320 platforms (SGI, DECstation, etc), and Sun3/4.
1324 Preliminary work has been put in to support the new Solaris OS from Sun. At
1325 this time, it can control and debug processes, but it is not capable of
1330 As always, many many bug fixes. The major areas were with g++, and mipsread.
1331 People using the MIPS-based platforms should experience fewer mysterious
1332 crashes and trashed symbol tables.
1334 *** Changes in GDB-4.4:
1336 * New machines supported (host and target)
1338 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1340 BSD Reno on Vax vax-dec-bsd
1341 Ultrix on Vax vax-dec-ultrix
1343 * New machines supported (target)
1345 AMD 29000 embedded, using EBMON a29k-none-none
1349 GDB continues to improve its handling of C++. `References' work better.
1350 The demangler has also been improved, and now deals with symbols mangled as
1351 per the Annotated C++ Reference Guide.
1353 GDB also now handles `stabs' symbol information embedded in MIPS
1354 `ecoff' symbol tables. Since the ecoff format was not easily
1355 extensible to handle new languages such as C++, this appeared to be a
1356 good way to put C++ debugging info into MIPS binaries. This option
1357 will be supported in the GNU C compiler, version 2, when it is
1360 * New features for SVR4
1362 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
1363 shared libraries. Debugging dynamically linked programs should present
1364 only minor differences from debugging statically linked programs.
1366 The `info proc' command will print out information about any process
1367 on an SVR4 system (including the one you are debugging). At the moment,
1368 it prints the address mappings of the process.
1370 If you bring up GDB on another SVR4 system, please send mail to
1371 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
1373 * Better dynamic linking support in SunOS
1375 Reading symbols from shared libraries which contain debugging symbols
1376 now works properly. However, there remain issues such as automatic
1377 skipping of `transfer vector' code during function calls, which
1378 make it harder to debug code in a shared library, than to debug the
1379 same code linked statically.
1383 GDB is now using the latest `getopt' routines from the FSF. This
1384 version accepts the -- prefix for options with long names. GDB will
1385 continue to accept the old forms (-option and +option) as well.
1386 Various single letter abbreviations for options have been explicity
1387 added to the option table so that they won't get overshadowed in the
1388 future by other options that begin with the same letter.
1392 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
1393 Many assorted bugs have been handled. Many more remain to be handled.
1394 See the various ChangeLog files (primarily in gdb and bfd) for details.
1397 *** Changes in GDB-4.3:
1399 * New machines supported (host and target)
1401 Amiga 3000 running Amix m68k-cbm-svr4 or amix
1402 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
1403 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
1405 * Almost SCO Unix support
1407 We had hoped to support:
1408 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
1409 (except for core file support), but we discovered very late in the release
1410 that it has problems with process groups that render gdb unusable. Sorry
1411 about that. I encourage people to fix it and post the fixes.
1413 * Preliminary ELF and DWARF support
1415 GDB can read ELF object files on System V Release 4, and can handle
1416 debugging records for C, in DWARF format, in ELF files. This support
1417 is preliminary. If you bring up GDB on another SVR4 system, please
1418 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
1423 GDB now uses the latest `readline' library. One user-visible change
1424 is that two tabs will list possible command completions, which previously
1425 required typing M-? (meta-question mark, or ESC ?).
1429 The `stepi' bug that many of you noticed has been squashed.
1430 Many bugs in C++ have been handled. Many more remain to be handled.
1431 See the various ChangeLog files (primarily in gdb and bfd) for details.
1433 * State of the MIPS world (in case you wondered):
1435 GDB can understand the symbol tables emitted by the compilers
1436 supplied by most vendors of MIPS-based machines, including DEC. These
1437 symbol tables are in a format that essentially nobody else uses.
1439 Some versions of gcc come with an assembler post-processor called
1440 mips-tfile. This program is required if you want to do source-level
1441 debugging of gcc-compiled programs. I believe FSF does not ship
1442 mips-tfile with gcc version 1, but it will eventually come with gcc
1445 Debugging of g++ output remains a problem. g++ version 1.xx does not
1446 really support it at all. (If you're lucky, you should be able to get
1447 line numbers and stack traces to work, but no parameters or local
1448 variables.) With some work it should be possible to improve the
1451 When gcc version 2 is released, you will have somewhat better luck.
1452 However, even then you will get confusing results for inheritance and
1455 We will eventually provide full debugging of g++ output on
1456 DECstations. This will probably involve some kind of stabs-in-ecoff
1457 encapulation, but the details have not been worked out yet.
1460 *** Changes in GDB-4.2:
1462 * Improved configuration
1464 Only one copy of `configure' exists now, and it is not self-modifying.
1465 Porting BFD is simpler.
1469 The `step' and `next' commands now only stop at the first instruction
1470 of a source line. This prevents the multiple stops that used to occur
1471 in switch statements, for-loops, etc. `Step' continues to stop if a
1472 function that has debugging information is called within the line.
1476 Lots of small bugs fixed. More remain.
1478 * New host supported (not target)
1480 Intel 386 PC clone running Mach i386-none-mach
1483 *** Changes in GDB-4.1:
1485 * Multiple source language support
1487 GDB now has internal scaffolding to handle several source languages.
1488 It determines the type of each source file from its filename extension,
1489 and will switch expression parsing and number formatting to match the
1490 language of the function in the currently selected stack frame.
1491 You can also specifically set the language to be used, with
1492 `set language c' or `set language modula-2'.
1496 GDB now has preliminary support for the GNU Modula-2 compiler,
1497 currently under development at the State University of New York at
1498 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1499 continue through the fall of 1991 and into 1992.
1501 Other Modula-2 compilers are currently not supported, and attempting to
1502 debug programs compiled with them will likely result in an error as the
1503 symbol table is read. Feel free to work on it, though!
1505 There are hooks in GDB for strict type checking and range checking,
1506 in the `Modula-2 philosophy', but they do not currently work.
1510 GDB can now write to executable and core files (e.g. patch
1511 a variable's value). You must turn this switch on, specify
1512 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1513 by assigning a new value to a variable. Modifications take
1516 * Automatic SunOS shared library reading
1518 When you run your program, GDB automatically determines where its
1519 shared libraries (if any) have been loaded, and reads their symbols.
1520 The `share' command is no longer needed. This also works when
1521 examining core files.
1525 You can specify the number of lines that the `list' command shows.
1528 * New machines supported (host and target)
1530 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1531 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1532 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1534 * New hosts supported (not targets)
1536 IBM RT/PC: romp-ibm-aix or rtpc
1538 * New targets supported (not hosts)
1540 AMD 29000 embedded with COFF a29k-none-coff
1541 AMD 29000 embedded with a.out a29k-none-aout
1542 Ultracomputer remote kernel debug a29k-nyu-kern
1544 * New remote interfaces
1550 *** Changes in GDB-4.0:
1554 Wide output is wrapped at good places to make the output more readable.
1556 Gdb now supports cross-debugging from a host machine of one type to a
1557 target machine of another type. Communication with the target system
1558 is over serial lines. The ``target'' command handles connecting to the
1559 remote system; the ``load'' command will download a program into the
1560 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1561 also supports debugging of realtime processes running under VxWorks,
1562 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1563 stub on the target system.
1565 New CPUs supported include the AMD 29000 and Intel 960.
1567 GDB now reads object files and symbol tables via a ``binary file''
1568 library, which allows a single copy of GDB to debug programs of multiple
1569 object file types such as a.out and coff.
1571 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1572 refcard.dvi and refcard.ps are available to format it).
1575 * Control-Variable user interface simplified
1577 All variables that control the operation of the debugger can be set
1578 by the ``set'' command, and displayed by the ``show'' command.
1580 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1581 ``Show prompt'' produces the response:
1582 Gdb's prompt is new-gdb=>.
1584 What follows are the NEW set commands. The command ``help set'' will
1585 print a complete list of old and new set commands. ``help set FOO''
1586 will give a longer description of the variable FOO. ``show'' will show
1587 all of the variable descriptions and their current settings.
1589 confirm on/off: Enables warning questions for operations that are
1590 hard to recover from, e.g. rerunning the program while
1591 it is already running. Default is ON.
1593 editing on/off: Enables EMACS style command line editing
1594 of input. Previous lines can be recalled with
1595 control-P, the current line can be edited with control-B,
1596 you can search for commands with control-R, etc.
1599 history filename NAME: NAME is where the gdb command history
1600 will be stored. The default is .gdb_history,
1601 or the value of the environment variable
1604 history size N: The size, in commands, of the command history. The
1605 default is 256, or the value of the environment variable
1608 history save on/off: If this value is set to ON, the history file will
1609 be saved after exiting gdb. If set to OFF, the
1610 file will not be saved. The default is OFF.
1612 history expansion on/off: If this value is set to ON, then csh-like
1613 history expansion will be performed on
1614 command line input. The default is OFF.
1616 radix N: Sets the default radix for input and output. It can be set
1617 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1618 in the current radix, so "set radix 10" is always a no-op.
1620 height N: This integer value is the number of lines on a page. Default
1621 is 24, the current `stty rows'' setting, or the ``li#''
1622 setting from the termcap entry matching the environment
1625 width N: This integer value is the number of characters on a line.
1626 Default is 80, the current `stty cols'' setting, or the ``co#''
1627 setting from the termcap entry matching the environment
1630 Note: ``set screensize'' is obsolete. Use ``set height'' and
1631 ``set width'' instead.
1633 print address on/off: Print memory addresses in various command displays,
1634 such as stack traces and structure values. Gdb looks
1635 more ``symbolic'' if you turn this off; it looks more
1636 ``machine level'' with it on. Default is ON.
1638 print array on/off: Prettyprint arrays. New convenient format! Default
1641 print demangle on/off: Print C++ symbols in "source" form if on,
1644 print asm-demangle on/off: Same, for assembler level printouts
1647 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1650 * Support for Epoch Environment.
1652 The epoch environment is a version of Emacs v18 with windowing. One
1653 new command, ``inspect'', is identical to ``print'', except that if you
1654 are running in the epoch environment, the value is printed in its own
1658 * Support for Shared Libraries
1660 GDB can now debug programs and core files that use SunOS shared libraries.
1661 Symbols from a shared library cannot be referenced
1662 before the shared library has been linked with the program (this
1663 happens after you type ``run'' and before the function main() is entered).
1664 At any time after this linking (including when examining core files
1665 from dynamically linked programs), gdb reads the symbols from each
1666 shared library when you type the ``sharedlibrary'' command.
1667 It can be abbreviated ``share''.
1669 sharedlibrary REGEXP: Load shared object library symbols for files
1670 matching a unix regular expression. No argument
1671 indicates to load symbols for all shared libraries.
1673 info sharedlibrary: Status of loaded shared libraries.
1678 A watchpoint stops execution of a program whenever the value of an
1679 expression changes. Checking for this slows down execution
1680 tremendously whenever you are in the scope of the expression, but is
1681 quite useful for catching tough ``bit-spreader'' or pointer misuse
1682 problems. Some machines such as the 386 have hardware for doing this
1683 more quickly, and future versions of gdb will use this hardware.
1685 watch EXP: Set a watchpoint (breakpoint) for an expression.
1687 info watchpoints: Information about your watchpoints.
1689 delete N: Deletes watchpoint number N (same as breakpoints).
1690 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1691 enable N: Re-enables watchpoint number N (same as breakpoints).
1694 * C++ multiple inheritance
1696 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1699 * C++ exception handling
1701 Gdb now supports limited C++ exception handling. Besides the existing
1702 ability to breakpoint on an exception handler, gdb can breakpoint on
1703 the raising of an exception (before the stack is peeled back to the
1706 catch FOO: If there is a FOO exception handler in the dynamic scope,
1707 set a breakpoint to catch exceptions which may be raised there.
1708 Multiple exceptions (``catch foo bar baz'') may be caught.
1710 info catch: Lists all exceptions which may be caught in the
1711 current stack frame.
1714 * Minor command changes
1716 The command ``call func (arg, arg, ...)'' now acts like the print
1717 command, except it does not print or save a value if the function's result
1718 is void. This is similar to dbx usage.
1720 The ``up'' and ``down'' commands now always print the frame they end up
1721 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1722 frames without printing.
1724 * New directory command
1726 'dir' now adds directories to the FRONT of the source search path.
1727 The path starts off empty. Source files that contain debug information
1728 about the directory in which they were compiled can be found even
1729 with an empty path; Sun CC and GCC include this information. If GDB can't
1730 find your source file in the current directory, type "dir .".
1732 * Configuring GDB for compilation
1734 For normal use, type ``./configure host''. See README or gdb.texinfo
1737 GDB now handles cross debugging. If you are remotely debugging between
1738 two different machines, type ``./configure host -target=targ''.
1739 Host is the machine where GDB will run; targ is the machine
1740 where the program that you are debugging will run.