1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB-4.15:
6 * New native configurations
8 Windows 95, Windows NT i[345]86-*-win32
12 ARM via RDP protocol arm-*-*
13 PowerPC via PPCBUG monitor powerpc{,le}-*-eabi*
14 PowerPC simulator powerpc{,le}-*-eabi if building with GCC
16 * Send break instead of ^C
18 The standard remote protocol now includes an option to send a break
19 rather than a ^C to the target in order to interrupt it. By default,
20 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
22 * Automatic tracking of dynamic object loading (HPUX only at the moment).
24 By default GDB will automatically keep track of objects as they are
25 loaded and unloaded by the dynamic linker. By using the command
26 "set stop-on-solib-events 1" you can arrange for GDB to stop the
27 inferior when shared library events occur, thus allowing you to
28 set breakpoints in shared libraries which are explicitly loaded by
31 Note this feature does not work on hpux8. On hpux9 you must link
32 /usr/lib/end.o into your program. This feature should work automatically
35 *** Changes in GDB-4.15:
39 The symbol reader for AIX GDB now uses partial symbol tables. This
40 can greatly improve startup time, especially for large executables.
42 * Remote targets use caching
44 Remote targets now use a data cache to speed up communication with the
45 remote side. The data cache could lead to incorrect results because
46 it doesn't know about volatile variables, thus making it impossible to
47 debug targets which use memory mapped I/O devices. `set remotecache
48 off' turns the the data cache off.
50 * Remote targets may have threads
52 The standard remote protocol now includes support for multiple threads
53 in the target system, using new protocol commands 'H' and 'T'. See
54 gdb/remote.c for details.
58 If GDB is configured with `--enable-netrom', then it will include
59 support for the NetROM ROM emulator from XLNT Designs. The NetROM
60 acts as though it is a bank of ROM on the target board, but you can
61 write into it over the network. GDB's support consists only of
62 support for fast loading into the emulated ROM; to debug, you must use
63 another protocol, such as standard remote protocol. The usual
64 sequence is something like
66 target nrom <netrom-hostname>
68 target remote <netrom-hostname>:1235
72 GDB now includes support for the Apple Macintosh, as a host only. It
73 may be run as either an MPW tool or as a standalone application, and
74 it can debug through the serial port. All the usual GDB commands are
75 available, but to the target command, you must supply "serial" as the
76 device type instead of "/dev/ttyXX". See mpw-README in the main
77 directory for more information on how to build. The MPW configuration
78 scripts */mpw-config.in support only a few targets, and only the
79 mips-idt-ecoff target has been tested.
83 GDB configuration now uses autoconf. This is not user-visible,
84 but does simplify configuration and building.
88 GDB now supports hpux10.
90 *** Changes in GDB-4.14:
92 * New native configurations
94 x86 FreeBSD i[345]86-*-freebsd
95 x86 NetBSD i[345]86-*-netbsd
96 NS32k NetBSD ns32k-*-netbsd
97 Sparc NetBSD sparc-*-netbsd
101 A29K VxWorks a29k-*-vxworks
102 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
103 CPU32 EST-300 emulator m68*-*-est*
104 PowerPC ELF powerpc-*-elf
107 * Alpha OSF/1 support for procfs
109 GDB now supports procfs under OSF/1-2.x and higher, which makes it
110 possible to attach to running processes. As the mounting of the /proc
111 filesystem is optional on the Alpha, GDB automatically determines
112 the availability of /proc during startup. This can lead to problems
113 if /proc is unmounted after GDB has been started.
115 * Arguments to user-defined commands
117 User commands may accept up to 10 arguments separated by whitespace.
118 Arguments are accessed within the user command via $arg0..$arg9. A
121 print $arg0 + $arg1 + $arg2
123 To execute the command use:
126 Defines the command "adder" which prints the sum of its three arguments.
127 Note the arguments are text substitutions, so they may reference variables,
128 use complex expressions, or even perform inferior function calls.
130 * New `if' and `while' commands
132 This makes it possible to write more sophisticated user-defined
133 commands. Both commands take a single argument, which is the
134 expression to evaluate, and must be followed by the commands to
135 execute, one per line, if the expression is nonzero, the list being
136 terminated by the word `end'. The `if' command list may include an
137 `else' word, which causes the following commands to be executed only
138 if the expression is zero.
140 * Fortran source language mode
142 GDB now includes partial support for Fortran 77. It will recognize
143 Fortran programs and can evaluate a subset of Fortran expressions, but
144 variables and functions may not be handled correctly. GDB will work
145 with G77, but does not yet know much about symbols emitted by other
148 * Better HPUX support
150 Most debugging facilities now work on dynamic executables for HPPAs
151 running hpux9 or later. You can attach to running dynamically linked
152 processes, but by default the dynamic libraries will be read-only, so
153 for instance you won't be able to put breakpoints in them. To change
154 that behavior do the following before running the program:
160 This will cause the libraries to be mapped private and read-write.
161 To revert to the normal behavior, do this:
167 You cannot set breakpoints or examine data in the library until after
168 the library is loaded if the function/data symbols do not have
171 GDB can now also read debug symbols produced by the HP C compiler on
172 HPPAs (sorry, no C++, Fortran or 68k support).
174 * Target byte order now dynamically selectable
176 You can choose which byte order to use with a target system, via the
177 commands "set endian big" and "set endian little", and you can see the
178 current setting by using "show endian". You can also give the command
179 "set endian auto", in which case GDB will use the byte order
180 associated with the executable. Currently, only embedded MIPS
181 configurations support dynamic selection of target byte order.
183 * New DOS host serial code
185 This version uses DPMI interrupts to handle buffered I/O, so you
186 no longer need to run asynctsr when debugging boards connected to
189 *** Changes in GDB-4.13:
191 * New "complete" command
193 This lists all the possible completions for the rest of the line, if it
194 were to be given as a command itself. This is intended for use by emacs.
196 * Trailing space optional in prompt
198 "set prompt" no longer adds a space for you after the prompt you set. This
199 allows you to set a prompt which ends in a space or one that does not.
201 * Breakpoint hit counts
203 "info break" now displays a count of the number of times the breakpoint
204 has been hit. This is especially useful in conjunction with "ignore"; you
205 can ignore a large number of breakpoint hits, look at the breakpoint info
206 to see how many times the breakpoint was hit, then run again, ignoring one
207 less than that number, and this will get you quickly to the last hit of
210 * Ability to stop printing at NULL character
212 "set print null-stop" will cause GDB to stop printing the characters of
213 an array when the first NULL is encountered. This is useful when large
214 arrays actually contain only short strings.
216 * Shared library breakpoints
218 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
219 breakpoints in shared libraries before the executable is run.
221 * Hardware watchpoints
223 There is a new hardware breakpoint for the watch command for sparclite
224 targets. See gdb/sparclite/hw_breakpoint.note.
226 Hardware watchpoints are also now supported under Linux.
230 Annotations have been added. These are for use with graphical interfaces,
231 and are still experimental. Currently only gdba.el uses these.
233 * Improved Irix 5 support
235 GDB now works properly with Irix 5.2.
237 * Improved HPPA support
239 GDB now works properly with the latest GCC and GAS.
241 * New native configurations
243 Sequent PTX4 i[34]86-sequent-ptx4
244 HPPA running OSF/1 hppa*-*-osf*
245 Atari TT running SVR4 m68*-*-sysv4*
246 RS/6000 LynxOS rs6000-*-lynxos*
250 OS/9000 i[34]86-*-os9k
251 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
254 * Hitachi SH7000 and E7000-PC ICE support
256 There is now support for communicating with the Hitachi E7000-PC ICE.
257 This is available automatically when GDB is configured for the SH.
261 As usual, a variety of small fixes and improvements, both generic
262 and configuration-specific. See the ChangeLog for more detail.
264 *** Changes in GDB-4.12:
266 * Irix 5 is now supported
270 GDB-4.12 on the HPPA has a number of changes which make it unable
271 to debug the output from the currently released versions of GCC and
272 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
273 of GCC and GAS, versions of these tools designed to work with GDB-4.12
274 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
277 *** Changes in GDB-4.11:
279 * User visible changes:
283 The "set remotedebug" option is now consistent between the mips remote
284 target, remote targets using the gdb-specific protocol, UDI (AMD's
285 debug protocol for the 29k) and the 88k bug monitor. It is now an
286 integer specifying a debug level (normally 0 or 1, but 2 means more
287 debugging info for the mips target).
289 * DEC Alpha native support
291 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
292 debug info, but GDB works fairly well with the DEC compiler and should
293 work with a future GCC release. See the README file for a few
294 Alpha-specific notes.
296 * Preliminary thread implementation
298 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
300 * LynxOS native and target support for 386
302 This release has been hosted on LynxOS 2.2, and also can be configured
303 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
306 * Improvements in C++ mangling/demangling.
308 This release has much better g++ debugging, specifically in name
309 mangling/demangling, virtual function calls, print virtual table,
310 call methods, ...etc.
312 *** Changes in GDB-4.10:
314 * User visible changes:
316 Remote debugging using the GDB-specific (`target remote') protocol now
317 supports the `load' command. This is only useful if you have some
318 other way of getting the stub to the target system, and you can put it
319 somewhere in memory where it won't get clobbered by the download.
321 Filename completion now works.
323 When run under emacs mode, the "info line" command now causes the
324 arrow to point to the line specified. Also, "info line" prints
325 addresses in symbolic form (as well as hex).
327 All vxworks based targets now support a user settable option, called
328 vxworks-timeout. This option represents the number of seconds gdb
329 should wait for responses to rpc's. You might want to use this if
330 your vxworks target is, perhaps, a slow software simulator or happens
331 to be on the far side of a thin network line.
335 This release contains support for using a DEC alpha as a GDB host for
336 cross debugging. Native alpha debugging is not supported yet.
339 *** Changes in GDB-4.9:
343 This is the first GDB release which is accompanied by a matching testsuite.
344 The testsuite requires installation of dejagnu, which should be available
345 via ftp from most sites that carry GNU software.
349 'Cfront' style demangling has had its name changed to 'ARM' style, to
350 emphasize that it was written from the specifications in the C++ Annotated
351 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
352 disclaimers, it still generated too much confusion with users attempting to
353 use gdb with AT&T cfront.
357 GDB now uses a standard remote interface to a simulator library.
358 So far, the library contains simulators for the Zilog Z8001/2, the
359 Hitachi H8/300, H8/500 and Super-H.
361 * New targets supported
363 H8/300 simulator h8300-hitachi-hms or h8300hms
364 H8/500 simulator h8500-hitachi-hms or h8500hms
365 SH simulator sh-hitachi-hms or sh
366 Z8000 simulator z8k-zilog-none or z8ksim
367 IDT MIPS board over serial line mips-idt-ecoff
369 Cross-debugging to GO32 targets is supported. It requires a custom
370 version of the i386-stub.c module which is integrated with the
371 GO32 memory extender.
373 * New remote protocols
375 MIPS remote debugging protocol.
377 * New source languages supported
379 This version includes preliminary support for Chill, a Pascal like language
380 used by telecommunications companies. Chill support is also being integrated
381 into the GNU compiler, but we don't know when it will be publically available.
384 *** Changes in GDB-4.8:
386 * HP Precision Architecture supported
388 GDB now supports HP PA-RISC machines running HPUX. A preliminary
389 version of this support was available as a set of patches from the
390 University of Utah. GDB does not support debugging of programs
391 compiled with the HP compiler, because HP will not document their file
392 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
393 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
395 Many problems in the preliminary version have been fixed.
397 * Faster and better demangling
399 We have improved template demangling and fixed numerous bugs in the GNU style
400 demangler. It can now handle type modifiers such as `static' or `const'. Wide
401 character types (wchar_t) are now supported. Demangling of each symbol is now
402 only done once, and is cached when the symbol table for a file is read in.
403 This results in a small increase in memory usage for C programs, a moderate
404 increase in memory usage for C++ programs, and a fantastic speedup in
407 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
408 from the specifications in the Annotated Reference Manual, which AT&T's
409 compiler does not actually implement.
411 * G++ multiple inheritance compiler problem
413 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
414 inheritance lattices was reworked to properly discover ambiguities. We
415 recently found an example which causes this new algorithm to fail in a
416 very subtle way, producing bad debug information for those classes.
417 The file 'gcc.patch' (in this directory) can be applied to gcc to
418 circumvent the problem. A future GCC release will contain a complete
421 The previous G++ debug info problem (mentioned below for the gdb-4.7
422 release) is fixed in gcc version 2.3.2.
424 * Improved configure script
426 The `configure' script will now attempt to guess your system type if
427 you don't supply a host system type. The old scheme of supplying a
428 host system triplet is preferable over using this. All the magic is
429 done in the new `config.guess' script. Examine it for details.
431 We have also brought our configure script much more in line with the FSF's
432 version. It now supports the --with-xxx options. In particular,
433 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
434 The resulting GDB will not be able to read arbitrary object file formats --
435 only the format ``expected'' to be used on the configured target system.
436 We hope to make this the default in a future release.
438 * Documentation improvements
440 There's new internal documentation on how to modify GDB, and how to
441 produce clean changes to the code. We implore people to read it
442 before submitting changes.
444 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
445 M4 macros. The new texinfo.tex is provided in this release. Pre-built
446 `info' files are also provided. To build `info' files from scratch,
447 you will need the latest `makeinfo' release, which will be available in
448 a future texinfo-X.Y release.
450 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
451 We're not sure exactly which versions have this problem, but it has
452 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
453 or better. If that isn't possible, there is a patch in
454 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
459 GDB now supports array constants that can be used in expressions typed in by
460 the user. The syntax is `{element, element, ...}'. Ie: you can now type
461 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
464 The new directory `gdb/sparclite' contains a program that demonstrates
465 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
467 * New native hosts supported
469 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
470 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
472 * New targets supported
474 AMD 29k family via UDI a29k-amd-udi or udi29k
476 * New file formats supported
478 BFD now supports reading HP/PA-RISC executables (SOM file format?),
479 HPUX core files, and SCO 3.2v2 core files.
483 Attaching to processes now works again; thanks for the many bug reports.
485 We have also stomped on a bunch of core dumps caused by
486 printf_filtered("%s") problems.
488 We eliminated a copyright problem on the rpc and ptrace header files
489 for VxWorks, which was discovered at the last minute during the 4.7
490 release. You should now be able to build a VxWorks GDB.
492 You can now interrupt gdb while an attached process is running. This
493 will cause the attached process to stop, and give control back to GDB.
495 We fixed problems caused by using too many file descriptors
496 for reading symbols from object files and libraries. This was
497 especially a problem for programs that used many (~100) shared
500 The `step' command now only enters a subroutine if there is line number
501 information for the subroutine. Otherwise it acts like the `next'
502 command. Previously, `step' would enter subroutines if there was
503 any debugging information about the routine. This avoids problems
504 when using `cc -g1' on MIPS machines.
506 * Internal improvements
508 GDB's internal interfaces have been improved to make it easier to support
509 debugging of multiple languages in the future.
511 GDB now uses a common structure for symbol information internally.
512 Minimal symbols (derived from linkage symbols in object files), partial
513 symbols (from a quick scan of debug information), and full symbols
514 contain a common subset of information, making it easier to write
515 shared code that handles any of them.
517 * New command line options
519 We now accept --silent as an alias for --quiet.
523 The memory-mapped-malloc library is now licensed under the GNU Library
524 General Public License.
526 *** Changes in GDB-4.7:
528 * Host/native/target split
530 GDB has had some major internal surgery to untangle the support for
531 hosts and remote targets. Now, when you configure GDB for a remote
532 target, it will no longer load in all of the support for debugging
533 local programs on the host. When fully completed and tested, this will
534 ensure that arbitrary host/target combinations are possible.
536 The primary conceptual shift is to separate the non-portable code in
537 GDB into three categories. Host specific code is required any time GDB
538 is compiled on that host, regardless of the target. Target specific
539 code relates to the peculiarities of the target, but can be compiled on
540 any host. Native specific code is everything else: it can only be
541 built when the host and target are the same system. Child process
542 handling and core file support are two common `native' examples.
544 GDB's use of /proc for controlling Unix child processes is now cleaner.
545 It has been split out into a single module under the `target_ops' vector,
546 plus two native-dependent functions for each system that uses /proc.
548 * New hosts supported
550 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
551 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
552 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
554 * New targets supported
556 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
557 68030 and CPU32 m68030-*-*, m68332-*-*
559 * New native hosts supported
561 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
562 (386bsd is not well tested yet)
563 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
565 * New file formats supported
567 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
568 supports reading of `a.out.adobe' object files, which are an a.out
569 format extended with minimal information about multiple sections.
573 `show copying' is the same as the old `info copying'.
574 `show warranty' is the same as `info warrantee'.
575 These were renamed for consistency. The old commands continue to work.
577 `info handle' is a new alias for `info signals'.
579 You can now define pre-command hooks, which attach arbitrary command
580 scripts to any command. The commands in the hook will be executed
581 prior to the user's command. You can also create a hook which will be
582 executed whenever the program stops. See gdb.texinfo.
586 We now deal with Cfront style name mangling, and can even extract type
587 info from mangled symbols. GDB can automatically figure out which
588 symbol mangling style your C++ compiler uses.
590 Calling of methods and virtual functions has been improved as well.
594 The crash that occured when debugging Sun Ansi-C compiled binaries is
595 fixed. This was due to mishandling of the extra N_SO stabs output
598 We also finally got Ultrix 4.2 running in house, and fixed core file
599 support, with help from a dozen people on the net.
601 John M. Farrell discovered that the reason that single-stepping was so
602 slow on all of the Mips based platforms (primarily SGI and DEC) was
603 that we were trying to demangle and lookup a symbol used for internal
604 purposes on every instruction that was being stepped through. Changing
605 the name of that symbol so that it couldn't be mistaken for a C++
606 mangled symbol sped things up a great deal.
608 Rich Pixley sped up symbol lookups in general by getting much smarter
609 about when C++ symbol mangling is necessary. This should make symbol
610 completion (TAB on the command line) much faster. It's not as fast as
611 we'd like, but it's significantly faster than gdb-4.6.
615 A new user controllable variable 'call_scratch_address' can
616 specify the location of a scratch area to be used when GDB
617 calls a function in the target. This is necessary because the
618 usual method of putting the scratch area on the stack does not work
619 in systems that have separate instruction and data spaces.
621 We integrated changes to support the 29k UDI (Universal Debugger
622 Interface), but discovered at the last minute that we didn't have all
623 of the appropriate copyright paperwork. We are working with AMD to
624 resolve this, and hope to have it available soon.
628 We have sped up the remote serial line protocol, especially for targets
629 with lots of registers. It now supports a new `expedited status' ('T')
630 message which can be used in place of the existing 'S' status message.
631 This allows the remote stub to send only the registers that GDB
632 needs to make a quick decision about single-stepping or conditional
633 breakpoints, eliminating the need to fetch the entire register set for
634 each instruction being stepped through.
636 The GDB remote serial protocol now implements a write-through cache for
637 registers, only re-reading the registers if the target has run.
639 There is also a new remote serial stub for SPARC processors. You can
640 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
641 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
642 processor with a serial port.
646 Configure.in files have become much easier to read and modify. A new
647 `table driven' format makes it more obvious what configurations are
648 supported, and what files each one uses.
652 There is a new opcodes library which will eventually contain all of the
653 disassembly routines and opcode tables. At present, it only contains
654 Sparc and Z8000 routines. This will allow the assembler, debugger, and
655 disassembler (binutils/objdump) to share these routines.
657 The libiberty library is now copylefted under the GNU Library General
658 Public License. This allows more liberal use, and was done so libg++
659 can use it. This makes no difference to GDB, since the Library License
660 grants all the rights from the General Public License.
664 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
665 reference to the stabs symbol info used by the debugger. It is (as far
666 as we know) the only published document on this fascinating topic. We
667 encourage you to read it, compare it to the stabs information on your
668 system, and send improvements on the document in general (to
669 bug-gdb@prep.ai.mit.edu).
671 And, of course, many bugs have been fixed.
674 *** Changes in GDB-4.6:
676 * Better support for C++ function names
678 GDB now accepts as input the "demangled form" of C++ overloaded function
679 names and member function names, and can do command completion on such names
680 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
681 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
682 Make use of command completion, it is your friend.
684 GDB also now accepts a variety of C++ mangled symbol formats. They are
685 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
686 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
687 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
688 for the list of formats.
690 * G++ symbol mangling problem
692 Recent versions of gcc have a bug in how they emit debugging information for
693 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
694 directory) can be applied to gcc to fix the problem. Alternatively, if you
695 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
696 usual symptom is difficulty with setting breakpoints on methods. GDB complains
697 about the method being non-existent. (We believe that version 2.2.2 of GCC has
700 * New 'maintenance' command
702 All of the commands related to hacking GDB internals have been moved out of
703 the main command set, and now live behind the 'maintenance' command. This
704 can also be abbreviated as 'mt'. The following changes were made:
706 dump-me -> maintenance dump-me
707 info all-breakpoints -> maintenance info breakpoints
708 printmsyms -> maintenance print msyms
709 printobjfiles -> maintenance print objfiles
710 printpsyms -> maintenance print psymbols
711 printsyms -> maintenance print symbols
713 The following commands are new:
715 maintenance demangle Call internal GDB demangler routine to
716 demangle a C++ link name and prints the result.
717 maintenance print type Print a type chain for a given symbol
719 * Change to .gdbinit file processing
721 We now read the $HOME/.gdbinit file before processing the argv arguments
722 (e.g. reading symbol files or core files). This allows global parameters to
723 be set, which will apply during the symbol reading. The ./.gdbinit is still
724 read after argv processing.
726 * New hosts supported
728 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
730 Linux support i386-unknown-linux or linux
732 We are also including code to support the HP/PA running BSD and HPUX. This
733 is almost guaranteed not to work, as we didn't have time to test or build it
734 for this release. We are including it so that the more adventurous (or
735 masochistic) of you can play with it. We also had major problems with the
736 fact that the compiler that we got from HP doesn't support the -g option.
739 * New targets supported
741 Hitachi H8/300 h8300-hitachi-hms or h8300hms
743 * More smarts about finding #include files
745 GDB now remembers the compilation directory for all include files, and for
746 all files from which C is generated (like yacc and lex sources). This
747 greatly improves GDB's ability to find yacc/lex sources, and include files,
748 especially if you are debugging your program from a directory different from
749 the one that contains your sources.
751 We also fixed a bug which caused difficulty with listing and setting
752 breakpoints in include files which contain C code. (In the past, you had to
753 try twice in order to list an include file that you hadn't looked at before.)
755 * Interesting infernals change
757 GDB now deals with arbitrary numbers of sections, where the symbols for each
758 section must be relocated relative to that section's landing place in the
759 target's address space. This work was needed to support ELF with embedded
760 stabs used by Solaris-2.0.
762 * Bug fixes (of course!)
764 There have been loads of fixes for the following things:
765 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
766 i960, stabs, DOS(GO32), procfs, etc...
768 See the ChangeLog for details.
770 *** Changes in GDB-4.5:
772 * New machines supported (host and target)
774 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
776 SGI Irix-4.x mips-sgi-irix4 or iris4
780 GDB now uses a new memory manager called mmalloc, based on gmalloc.
781 Mmalloc is capable of handling mutiple heaps of memory. It is also
782 capable of saving a heap to a file, and then mapping it back in later.
783 This can be used to greatly speedup the startup of GDB by using a
784 pre-parsed symbol table which lives in a mmalloc managed heap. For
785 more details, please read mmalloc/mmalloc.texi.
789 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
790 'help info proc' for details.
792 * MIPS ecoff symbol table format
794 The code that reads MIPS symbol table format is now supported on all hosts.
795 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
798 * File name changes for MS-DOS
800 Many files in the config directories have been renamed to make it easier to
801 support GDB on MS-DOSe systems (which have very restrictive file name
802 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
803 environment) is close to working but has some remaining problems. Note
804 that debugging of DOS programs is not supported, due to limitations
805 in the ``operating system'', but it can be used to host cross-debugging.
807 * Cross byte order fixes
809 Many fixes have been made to support cross debugging of Sparc and MIPS
810 targets from hosts whose byte order differs.
812 * New -mapped and -readnow options
814 If memory-mapped files are available on your system through the 'mmap'
815 system call, you can use the -mapped option on the `file' or
816 `symbol-file' commands to cause GDB to write the symbols from your
817 program into a reusable file. If the program you are debugging is
818 called `/path/fred', the mapped symbol file will be `./fred.syms'.
819 Future GDB debugging sessions will notice the presence of this file,
820 and will quickly map in symbol information from it, rather than reading
821 the symbol table from the executable program. Using the '-mapped'
822 option in a GDB `file' or `symbol-file' command has the same effect as
823 starting GDB with the '-mapped' command-line option.
825 You can cause GDB to read the entire symbol table immediately by using
826 the '-readnow' option with any of the commands that load symbol table
827 information (or on the GDB command line). This makes the command
828 slower, but makes future operations faster.
830 The -mapped and -readnow options are typically combined in order to
831 build a `fred.syms' file that contains complete symbol information.
832 A simple GDB invocation to do nothing but build a `.syms' file for future
835 gdb -batch -nx -mapped -readnow programname
837 The `.syms' file is specific to the host machine on which GDB is run.
838 It holds an exact image of GDB's internal symbol table. It cannot be
839 shared across multiple host platforms.
843 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
844 siglongjmp() without losing control. This feature has not yet been ported to
845 all systems. It currently works on many 386 platforms, all MIPS-based
846 platforms (SGI, DECstation, etc), and Sun3/4.
850 Preliminary work has been put in to support the new Solaris OS from Sun. At
851 this time, it can control and debug processes, but it is not capable of
856 As always, many many bug fixes. The major areas were with g++, and mipsread.
857 People using the MIPS-based platforms should experience fewer mysterious
858 crashes and trashed symbol tables.
860 *** Changes in GDB-4.4:
862 * New machines supported (host and target)
864 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
866 BSD Reno on Vax vax-dec-bsd
867 Ultrix on Vax vax-dec-ultrix
869 * New machines supported (target)
871 AMD 29000 embedded, using EBMON a29k-none-none
875 GDB continues to improve its handling of C++. `References' work better.
876 The demangler has also been improved, and now deals with symbols mangled as
877 per the Annotated C++ Reference Guide.
879 GDB also now handles `stabs' symbol information embedded in MIPS
880 `ecoff' symbol tables. Since the ecoff format was not easily
881 extensible to handle new languages such as C++, this appeared to be a
882 good way to put C++ debugging info into MIPS binaries. This option
883 will be supported in the GNU C compiler, version 2, when it is
886 * New features for SVR4
888 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
889 shared libraries. Debugging dynamically linked programs should present
890 only minor differences from debugging statically linked programs.
892 The `info proc' command will print out information about any process
893 on an SVR4 system (including the one you are debugging). At the moment,
894 it prints the address mappings of the process.
896 If you bring up GDB on another SVR4 system, please send mail to
897 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
899 * Better dynamic linking support in SunOS
901 Reading symbols from shared libraries which contain debugging symbols
902 now works properly. However, there remain issues such as automatic
903 skipping of `transfer vector' code during function calls, which
904 make it harder to debug code in a shared library, than to debug the
905 same code linked statically.
909 GDB is now using the latest `getopt' routines from the FSF. This
910 version accepts the -- prefix for options with long names. GDB will
911 continue to accept the old forms (-option and +option) as well.
912 Various single letter abbreviations for options have been explicity
913 added to the option table so that they won't get overshadowed in the
914 future by other options that begin with the same letter.
918 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
919 Many assorted bugs have been handled. Many more remain to be handled.
920 See the various ChangeLog files (primarily in gdb and bfd) for details.
923 *** Changes in GDB-4.3:
925 * New machines supported (host and target)
927 Amiga 3000 running Amix m68k-cbm-svr4 or amix
928 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
929 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
931 * Almost SCO Unix support
933 We had hoped to support:
934 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
935 (except for core file support), but we discovered very late in the release
936 that it has problems with process groups that render gdb unusable. Sorry
937 about that. I encourage people to fix it and post the fixes.
939 * Preliminary ELF and DWARF support
941 GDB can read ELF object files on System V Release 4, and can handle
942 debugging records for C, in DWARF format, in ELF files. This support
943 is preliminary. If you bring up GDB on another SVR4 system, please
944 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
949 GDB now uses the latest `readline' library. One user-visible change
950 is that two tabs will list possible command completions, which previously
951 required typing M-? (meta-question mark, or ESC ?).
955 The `stepi' bug that many of you noticed has been squashed.
956 Many bugs in C++ have been handled. Many more remain to be handled.
957 See the various ChangeLog files (primarily in gdb and bfd) for details.
959 * State of the MIPS world (in case you wondered):
961 GDB can understand the symbol tables emitted by the compilers
962 supplied by most vendors of MIPS-based machines, including DEC. These
963 symbol tables are in a format that essentially nobody else uses.
965 Some versions of gcc come with an assembler post-processor called
966 mips-tfile. This program is required if you want to do source-level
967 debugging of gcc-compiled programs. I believe FSF does not ship
968 mips-tfile with gcc version 1, but it will eventually come with gcc
971 Debugging of g++ output remains a problem. g++ version 1.xx does not
972 really support it at all. (If you're lucky, you should be able to get
973 line numbers and stack traces to work, but no parameters or local
974 variables.) With some work it should be possible to improve the
977 When gcc version 2 is released, you will have somewhat better luck.
978 However, even then you will get confusing results for inheritance and
981 We will eventually provide full debugging of g++ output on
982 DECstations. This will probably involve some kind of stabs-in-ecoff
983 encapulation, but the details have not been worked out yet.
986 *** Changes in GDB-4.2:
988 * Improved configuration
990 Only one copy of `configure' exists now, and it is not self-modifying.
991 Porting BFD is simpler.
995 The `step' and `next' commands now only stop at the first instruction
996 of a source line. This prevents the multiple stops that used to occur
997 in switch statements, for-loops, etc. `Step' continues to stop if a
998 function that has debugging information is called within the line.
1002 Lots of small bugs fixed. More remain.
1004 * New host supported (not target)
1006 Intel 386 PC clone running Mach i386-none-mach
1009 *** Changes in GDB-4.1:
1011 * Multiple source language support
1013 GDB now has internal scaffolding to handle several source languages.
1014 It determines the type of each source file from its filename extension,
1015 and will switch expression parsing and number formatting to match the
1016 language of the function in the currently selected stack frame.
1017 You can also specifically set the language to be used, with
1018 `set language c' or `set language modula-2'.
1022 GDB now has preliminary support for the GNU Modula-2 compiler,
1023 currently under development at the State University of New York at
1024 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1025 continue through the fall of 1991 and into 1992.
1027 Other Modula-2 compilers are currently not supported, and attempting to
1028 debug programs compiled with them will likely result in an error as the
1029 symbol table is read. Feel free to work on it, though!
1031 There are hooks in GDB for strict type checking and range checking,
1032 in the `Modula-2 philosophy', but they do not currently work.
1036 GDB can now write to executable and core files (e.g. patch
1037 a variable's value). You must turn this switch on, specify
1038 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1039 by assigning a new value to a variable. Modifications take
1042 * Automatic SunOS shared library reading
1044 When you run your program, GDB automatically determines where its
1045 shared libraries (if any) have been loaded, and reads their symbols.
1046 The `share' command is no longer needed. This also works when
1047 examining core files.
1051 You can specify the number of lines that the `list' command shows.
1054 * New machines supported (host and target)
1056 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1057 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1058 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1060 * New hosts supported (not targets)
1062 IBM RT/PC: romp-ibm-aix or rtpc
1064 * New targets supported (not hosts)
1066 AMD 29000 embedded with COFF a29k-none-coff
1067 AMD 29000 embedded with a.out a29k-none-aout
1068 Ultracomputer remote kernel debug a29k-nyu-kern
1070 * New remote interfaces
1076 *** Changes in GDB-4.0:
1080 Wide output is wrapped at good places to make the output more readable.
1082 Gdb now supports cross-debugging from a host machine of one type to a
1083 target machine of another type. Communication with the target system
1084 is over serial lines. The ``target'' command handles connecting to the
1085 remote system; the ``load'' command will download a program into the
1086 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1087 also supports debugging of realtime processes running under VxWorks,
1088 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1089 stub on the target system.
1091 New CPUs supported include the AMD 29000 and Intel 960.
1093 GDB now reads object files and symbol tables via a ``binary file''
1094 library, which allows a single copy of GDB to debug programs of multiple
1095 object file types such as a.out and coff.
1097 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1098 refcard.dvi and refcard.ps are available to format it).
1101 * Control-Variable user interface simplified
1103 All variables that control the operation of the debugger can be set
1104 by the ``set'' command, and displayed by the ``show'' command.
1106 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1107 ``Show prompt'' produces the response:
1108 Gdb's prompt is new-gdb=>.
1110 What follows are the NEW set commands. The command ``help set'' will
1111 print a complete list of old and new set commands. ``help set FOO''
1112 will give a longer description of the variable FOO. ``show'' will show
1113 all of the variable descriptions and their current settings.
1115 confirm on/off: Enables warning questions for operations that are
1116 hard to recover from, e.g. rerunning the program while
1117 it is already running. Default is ON.
1119 editing on/off: Enables EMACS style command line editing
1120 of input. Previous lines can be recalled with
1121 control-P, the current line can be edited with control-B,
1122 you can search for commands with control-R, etc.
1125 history filename NAME: NAME is where the gdb command history
1126 will be stored. The default is .gdb_history,
1127 or the value of the environment variable
1130 history size N: The size, in commands, of the command history. The
1131 default is 256, or the value of the environment variable
1134 history save on/off: If this value is set to ON, the history file will
1135 be saved after exiting gdb. If set to OFF, the
1136 file will not be saved. The default is OFF.
1138 history expansion on/off: If this value is set to ON, then csh-like
1139 history expansion will be performed on
1140 command line input. The default is OFF.
1142 radix N: Sets the default radix for input and output. It can be set
1143 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1144 in the current radix, so "set radix 10" is always a no-op.
1146 height N: This integer value is the number of lines on a page. Default
1147 is 24, the current `stty rows'' setting, or the ``li#''
1148 setting from the termcap entry matching the environment
1151 width N: This integer value is the number of characters on a line.
1152 Default is 80, the current `stty cols'' setting, or the ``co#''
1153 setting from the termcap entry matching the environment
1156 Note: ``set screensize'' is obsolete. Use ``set height'' and
1157 ``set width'' instead.
1159 print address on/off: Print memory addresses in various command displays,
1160 such as stack traces and structure values. Gdb looks
1161 more ``symbolic'' if you turn this off; it looks more
1162 ``machine level'' with it on. Default is ON.
1164 print array on/off: Prettyprint arrays. New convenient format! Default
1167 print demangle on/off: Print C++ symbols in "source" form if on,
1170 print asm-demangle on/off: Same, for assembler level printouts
1173 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1176 * Support for Epoch Environment.
1178 The epoch environment is a version of Emacs v18 with windowing. One
1179 new command, ``inspect'', is identical to ``print'', except that if you
1180 are running in the epoch environment, the value is printed in its own
1184 * Support for Shared Libraries
1186 GDB can now debug programs and core files that use SunOS shared libraries.
1187 Symbols from a shared library cannot be referenced
1188 before the shared library has been linked with the program (this
1189 happens after you type ``run'' and before the function main() is entered).
1190 At any time after this linking (including when examining core files
1191 from dynamically linked programs), gdb reads the symbols from each
1192 shared library when you type the ``sharedlibrary'' command.
1193 It can be abbreviated ``share''.
1195 sharedlibrary REGEXP: Load shared object library symbols for files
1196 matching a unix regular expression. No argument
1197 indicates to load symbols for all shared libraries.
1199 info sharedlibrary: Status of loaded shared libraries.
1204 A watchpoint stops execution of a program whenever the value of an
1205 expression changes. Checking for this slows down execution
1206 tremendously whenever you are in the scope of the expression, but is
1207 quite useful for catching tough ``bit-spreader'' or pointer misuse
1208 problems. Some machines such as the 386 have hardware for doing this
1209 more quickly, and future versions of gdb will use this hardware.
1211 watch EXP: Set a watchpoint (breakpoint) for an expression.
1213 info watchpoints: Information about your watchpoints.
1215 delete N: Deletes watchpoint number N (same as breakpoints).
1216 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1217 enable N: Re-enables watchpoint number N (same as breakpoints).
1220 * C++ multiple inheritance
1222 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1225 * C++ exception handling
1227 Gdb now supports limited C++ exception handling. Besides the existing
1228 ability to breakpoint on an exception handler, gdb can breakpoint on
1229 the raising of an exception (before the stack is peeled back to the
1232 catch FOO: If there is a FOO exception handler in the dynamic scope,
1233 set a breakpoint to catch exceptions which may be raised there.
1234 Multiple exceptions (``catch foo bar baz'') may be caught.
1236 info catch: Lists all exceptions which may be caught in the
1237 current stack frame.
1240 * Minor command changes
1242 The command ``call func (arg, arg, ...)'' now acts like the print
1243 command, except it does not print or save a value if the function's result
1244 is void. This is similar to dbx usage.
1246 The ``up'' and ``down'' commands now always print the frame they end up
1247 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1248 frames without printing.
1250 * New directory command
1252 'dir' now adds directories to the FRONT of the source search path.
1253 The path starts off empty. Source files that contain debug information
1254 about the directory in which they were compiled can be found even
1255 with an empty path; Sun CC and GCC include this information. If GDB can't
1256 find your source file in the current directory, type "dir .".
1258 * Configuring GDB for compilation
1260 For normal use, type ``./configure host''. See README or gdb.texinfo
1263 GDB now handles cross debugging. If you are remotely debugging between
1264 two different machines, type ``./configure host -target=targ''.
1265 Host is the machine where GDB will run; targ is the machine
1266 where the program that you are debugging will run.
projects / external / binutils.git / blob