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-*-*
14 *** Changes in GDB-4.15:
18 The symbol reader for AIX GDB now uses partial symbol tables. This
19 can greatly improve startup time, especially for large executables.
21 * Remote targets use caching
23 Remote targets now use a data cache to speed up communication with the
24 remote side. The data cache could lead to incorrect results because
25 it doesn't know about volatile variables, thus making it impossible to
26 debug targets which use memory mapped I/O devices. `set remotecache
27 off' turns the the data cache off.
29 * Remote targets may have threads
31 The standard remote protocol now includes support for multiple threads
32 in the target system, using new protocol commands 'H' and 'T'. See
33 gdb/remote.c for details.
37 If GDB is configured with `--enable-netrom', then it will include
38 support for the NetROM ROM emulator from XLNT Designs. The NetROM
39 acts as though it is a bank of ROM on the target board, but you can
40 write into it over the network. GDB's support consists only of
41 support for fast loading into the emulated ROM; to debug, you must use
42 another protocol, such as standard remote protocol. The usual
43 sequence is something like
45 target nrom <netrom-hostname>
47 target remote <netrom-hostname>:1235
51 GDB now includes support for the Apple Macintosh, as a host only. It
52 may be run as either an MPW tool or as a standalone application, and
53 it can debug through the serial port. All the usual GDB commands are
54 available, but to the target command, you must supply "serial" as the
55 device type instead of "/dev/ttyXX". See mpw-README in the main
56 directory for more information on how to build. The MPW configuration
57 scripts */mpw-config.in support only a few targets, and only the
58 mips-idt-ecoff target has been tested.
62 GDB configuration now uses autoconf. This is not user-visible,
63 but does simplify configuration and building.
67 GDB now supports hpux10.
69 *** Changes in GDB-4.14:
71 * New native configurations
73 x86 FreeBSD i[345]86-*-freebsd
74 x86 NetBSD i[345]86-*-netbsd
75 NS32k NetBSD ns32k-*-netbsd
76 Sparc NetBSD sparc-*-netbsd
80 A29K VxWorks a29k-*-vxworks
81 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
82 CPU32 EST-300 emulator m68*-*-est*
83 PowerPC ELF powerpc-*-elf
86 * Alpha OSF/1 support for procfs
88 GDB now supports procfs under OSF/1-2.x and higher, which makes it
89 possible to attach to running processes. As the mounting of the /proc
90 filesystem is optional on the Alpha, GDB automatically determines
91 the availability of /proc during startup. This can lead to problems
92 if /proc is unmounted after GDB has been started.
94 * Arguments to user-defined commands
96 User commands may accept up to 10 arguments separated by whitespace.
97 Arguments are accessed within the user command via $arg0..$arg9. A
100 print $arg0 + $arg1 + $arg2
102 To execute the command use:
105 Defines the command "adder" which prints the sum of its three arguments.
106 Note the arguments are text substitutions, so they may reference variables,
107 use complex expressions, or even perform inferior function calls.
109 * New `if' and `while' commands
111 This makes it possible to write more sophisticated user-defined
112 commands. Both commands take a single argument, which is the
113 expression to evaluate, and must be followed by the commands to
114 execute, one per line, if the expression is nonzero, the list being
115 terminated by the word `end'. The `if' command list may include an
116 `else' word, which causes the following commands to be executed only
117 if the expression is zero.
119 * Fortran source language mode
121 GDB now includes partial support for Fortran 77. It will recognize
122 Fortran programs and can evaluate a subset of Fortran expressions, but
123 variables and functions may not be handled correctly. GDB will work
124 with G77, but does not yet know much about symbols emitted by other
127 * Better HPUX support
129 Most debugging facilities now work on dynamic executables for HPPAs
130 running hpux9 or later. You can attach to running dynamically linked
131 processes, but by default the dynamic libraries will be read-only, so
132 for instance you won't be able to put breakpoints in them. To change
133 that behavior do the following before running the program:
139 This will cause the libraries to be mapped private and read-write.
140 To revert to the normal behavior, do this:
146 You cannot set breakpoints or examine data in the library until after
147 the library is loaded if the function/data symbols do not have
150 GDB can now also read debug symbols produced by the HP C compiler on
151 HPPAs (sorry, no C++, Fortran or 68k support).
153 * Target byte order now dynamically selectable
155 You can choose which byte order to use with a target system, via the
156 commands "set endian big" and "set endian little", and you can see the
157 current setting by using "show endian". You can also give the command
158 "set endian auto", in which case GDB will use the byte order
159 associated with the executable. Currently, only embedded MIPS
160 configurations support dynamic selection of target byte order.
162 * New DOS host serial code
164 This version uses DPMI interrupts to handle buffered I/O, so you
165 no longer need to run asynctsr when debugging boards connected to
168 *** Changes in GDB-4.13:
170 * New "complete" command
172 This lists all the possible completions for the rest of the line, if it
173 were to be given as a command itself. This is intended for use by emacs.
175 * Trailing space optional in prompt
177 "set prompt" no longer adds a space for you after the prompt you set. This
178 allows you to set a prompt which ends in a space or one that does not.
180 * Breakpoint hit counts
182 "info break" now displays a count of the number of times the breakpoint
183 has been hit. This is especially useful in conjunction with "ignore"; you
184 can ignore a large number of breakpoint hits, look at the breakpoint info
185 to see how many times the breakpoint was hit, then run again, ignoring one
186 less than that number, and this will get you quickly to the last hit of
189 * Ability to stop printing at NULL character
191 "set print null-stop" will cause GDB to stop printing the characters of
192 an array when the first NULL is encountered. This is useful when large
193 arrays actually contain only short strings.
195 * Shared library breakpoints
197 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
198 breakpoints in shared libraries before the executable is run.
200 * Hardware watchpoints
202 There is a new hardware breakpoint for the watch command for sparclite
203 targets. See gdb/sparclite/hw_breakpoint.note.
205 Hardware watchpoints are also now supported under Linux.
209 Annotations have been added. These are for use with graphical interfaces,
210 and are still experimental. Currently only gdba.el uses these.
212 * Improved Irix 5 support
214 GDB now works properly with Irix 5.2.
216 * Improved HPPA support
218 GDB now works properly with the latest GCC and GAS.
220 * New native configurations
222 Sequent PTX4 i[34]86-sequent-ptx4
223 HPPA running OSF/1 hppa*-*-osf*
224 Atari TT running SVR4 m68*-*-sysv4*
225 RS/6000 LynxOS rs6000-*-lynxos*
229 OS/9000 i[34]86-*-os9k
230 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
233 * Hitachi SH7000 and E7000-PC ICE support
235 There is now support for communicating with the Hitachi E7000-PC ICE.
236 This is available automatically when GDB is configured for the SH.
240 As usual, a variety of small fixes and improvements, both generic
241 and configuration-specific. See the ChangeLog for more detail.
243 *** Changes in GDB-4.12:
245 * Irix 5 is now supported
249 GDB-4.12 on the HPPA has a number of changes which make it unable
250 to debug the output from the currently released versions of GCC and
251 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
252 of GCC and GAS, versions of these tools designed to work with GDB-4.12
253 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
256 *** Changes in GDB-4.11:
258 * User visible changes:
262 The "set remotedebug" option is now consistent between the mips remote
263 target, remote targets using the gdb-specific protocol, UDI (AMD's
264 debug protocol for the 29k) and the 88k bug monitor. It is now an
265 integer specifying a debug level (normally 0 or 1, but 2 means more
266 debugging info for the mips target).
268 * DEC Alpha native support
270 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
271 debug info, but GDB works fairly well with the DEC compiler and should
272 work with a future GCC release. See the README file for a few
273 Alpha-specific notes.
275 * Preliminary thread implementation
277 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
279 * LynxOS native and target support for 386
281 This release has been hosted on LynxOS 2.2, and also can be configured
282 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
285 * Improvements in C++ mangling/demangling.
287 This release has much better g++ debugging, specifically in name
288 mangling/demangling, virtual function calls, print virtual table,
289 call methods, ...etc.
291 *** Changes in GDB-4.10:
293 * User visible changes:
295 Remote debugging using the GDB-specific (`target remote') protocol now
296 supports the `load' command. This is only useful if you have some
297 other way of getting the stub to the target system, and you can put it
298 somewhere in memory where it won't get clobbered by the download.
300 Filename completion now works.
302 When run under emacs mode, the "info line" command now causes the
303 arrow to point to the line specified. Also, "info line" prints
304 addresses in symbolic form (as well as hex).
306 All vxworks based targets now support a user settable option, called
307 vxworks-timeout. This option represents the number of seconds gdb
308 should wait for responses to rpc's. You might want to use this if
309 your vxworks target is, perhaps, a slow software simulator or happens
310 to be on the far side of a thin network line.
314 This release contains support for using a DEC alpha as a GDB host for
315 cross debugging. Native alpha debugging is not supported yet.
318 *** Changes in GDB-4.9:
322 This is the first GDB release which is accompanied by a matching testsuite.
323 The testsuite requires installation of dejagnu, which should be available
324 via ftp from most sites that carry GNU software.
328 'Cfront' style demangling has had its name changed to 'ARM' style, to
329 emphasize that it was written from the specifications in the C++ Annotated
330 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
331 disclaimers, it still generated too much confusion with users attempting to
332 use gdb with AT&T cfront.
336 GDB now uses a standard remote interface to a simulator library.
337 So far, the library contains simulators for the Zilog Z8001/2, the
338 Hitachi H8/300, H8/500 and Super-H.
340 * New targets supported
342 H8/300 simulator h8300-hitachi-hms or h8300hms
343 H8/500 simulator h8500-hitachi-hms or h8500hms
344 SH simulator sh-hitachi-hms or sh
345 Z8000 simulator z8k-zilog-none or z8ksim
346 IDT MIPS board over serial line mips-idt-ecoff
348 Cross-debugging to GO32 targets is supported. It requires a custom
349 version of the i386-stub.c module which is integrated with the
350 GO32 memory extender.
352 * New remote protocols
354 MIPS remote debugging protocol.
356 * New source languages supported
358 This version includes preliminary support for Chill, a Pascal like language
359 used by telecommunications companies. Chill support is also being integrated
360 into the GNU compiler, but we don't know when it will be publically available.
363 *** Changes in GDB-4.8:
365 * HP Precision Architecture supported
367 GDB now supports HP PA-RISC machines running HPUX. A preliminary
368 version of this support was available as a set of patches from the
369 University of Utah. GDB does not support debugging of programs
370 compiled with the HP compiler, because HP will not document their file
371 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
372 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
374 Many problems in the preliminary version have been fixed.
376 * Faster and better demangling
378 We have improved template demangling and fixed numerous bugs in the GNU style
379 demangler. It can now handle type modifiers such as `static' or `const'. Wide
380 character types (wchar_t) are now supported. Demangling of each symbol is now
381 only done once, and is cached when the symbol table for a file is read in.
382 This results in a small increase in memory usage for C programs, a moderate
383 increase in memory usage for C++ programs, and a fantastic speedup in
386 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
387 from the specifications in the Annotated Reference Manual, which AT&T's
388 compiler does not actually implement.
390 * G++ multiple inheritance compiler problem
392 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
393 inheritance lattices was reworked to properly discover ambiguities. We
394 recently found an example which causes this new algorithm to fail in a
395 very subtle way, producing bad debug information for those classes.
396 The file 'gcc.patch' (in this directory) can be applied to gcc to
397 circumvent the problem. A future GCC release will contain a complete
400 The previous G++ debug info problem (mentioned below for the gdb-4.7
401 release) is fixed in gcc version 2.3.2.
403 * Improved configure script
405 The `configure' script will now attempt to guess your system type if
406 you don't supply a host system type. The old scheme of supplying a
407 host system triplet is preferable over using this. All the magic is
408 done in the new `config.guess' script. Examine it for details.
410 We have also brought our configure script much more in line with the FSF's
411 version. It now supports the --with-xxx options. In particular,
412 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
413 The resulting GDB will not be able to read arbitrary object file formats --
414 only the format ``expected'' to be used on the configured target system.
415 We hope to make this the default in a future release.
417 * Documentation improvements
419 There's new internal documentation on how to modify GDB, and how to
420 produce clean changes to the code. We implore people to read it
421 before submitting changes.
423 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
424 M4 macros. The new texinfo.tex is provided in this release. Pre-built
425 `info' files are also provided. To build `info' files from scratch,
426 you will need the latest `makeinfo' release, which will be available in
427 a future texinfo-X.Y release.
429 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
430 We're not sure exactly which versions have this problem, but it has
431 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
432 or better. If that isn't possible, there is a patch in
433 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
438 GDB now supports array constants that can be used in expressions typed in by
439 the user. The syntax is `{element, element, ...}'. Ie: you can now type
440 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
443 The new directory `gdb/sparclite' contains a program that demonstrates
444 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
446 * New native hosts supported
448 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
449 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
451 * New targets supported
453 AMD 29k family via UDI a29k-amd-udi or udi29k
455 * New file formats supported
457 BFD now supports reading HP/PA-RISC executables (SOM file format?),
458 HPUX core files, and SCO 3.2v2 core files.
462 Attaching to processes now works again; thanks for the many bug reports.
464 We have also stomped on a bunch of core dumps caused by
465 printf_filtered("%s") problems.
467 We eliminated a copyright problem on the rpc and ptrace header files
468 for VxWorks, which was discovered at the last minute during the 4.7
469 release. You should now be able to build a VxWorks GDB.
471 You can now interrupt gdb while an attached process is running. This
472 will cause the attached process to stop, and give control back to GDB.
474 We fixed problems caused by using too many file descriptors
475 for reading symbols from object files and libraries. This was
476 especially a problem for programs that used many (~100) shared
479 The `step' command now only enters a subroutine if there is line number
480 information for the subroutine. Otherwise it acts like the `next'
481 command. Previously, `step' would enter subroutines if there was
482 any debugging information about the routine. This avoids problems
483 when using `cc -g1' on MIPS machines.
485 * Internal improvements
487 GDB's internal interfaces have been improved to make it easier to support
488 debugging of multiple languages in the future.
490 GDB now uses a common structure for symbol information internally.
491 Minimal symbols (derived from linkage symbols in object files), partial
492 symbols (from a quick scan of debug information), and full symbols
493 contain a common subset of information, making it easier to write
494 shared code that handles any of them.
496 * New command line options
498 We now accept --silent as an alias for --quiet.
502 The memory-mapped-malloc library is now licensed under the GNU Library
503 General Public License.
505 *** Changes in GDB-4.7:
507 * Host/native/target split
509 GDB has had some major internal surgery to untangle the support for
510 hosts and remote targets. Now, when you configure GDB for a remote
511 target, it will no longer load in all of the support for debugging
512 local programs on the host. When fully completed and tested, this will
513 ensure that arbitrary host/target combinations are possible.
515 The primary conceptual shift is to separate the non-portable code in
516 GDB into three categories. Host specific code is required any time GDB
517 is compiled on that host, regardless of the target. Target specific
518 code relates to the peculiarities of the target, but can be compiled on
519 any host. Native specific code is everything else: it can only be
520 built when the host and target are the same system. Child process
521 handling and core file support are two common `native' examples.
523 GDB's use of /proc for controlling Unix child processes is now cleaner.
524 It has been split out into a single module under the `target_ops' vector,
525 plus two native-dependent functions for each system that uses /proc.
527 * New hosts supported
529 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
530 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
531 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
533 * New targets supported
535 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
536 68030 and CPU32 m68030-*-*, m68332-*-*
538 * New native hosts supported
540 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
541 (386bsd is not well tested yet)
542 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
544 * New file formats supported
546 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
547 supports reading of `a.out.adobe' object files, which are an a.out
548 format extended with minimal information about multiple sections.
552 `show copying' is the same as the old `info copying'.
553 `show warranty' is the same as `info warrantee'.
554 These were renamed for consistency. The old commands continue to work.
556 `info handle' is a new alias for `info signals'.
558 You can now define pre-command hooks, which attach arbitrary command
559 scripts to any command. The commands in the hook will be executed
560 prior to the user's command. You can also create a hook which will be
561 executed whenever the program stops. See gdb.texinfo.
565 We now deal with Cfront style name mangling, and can even extract type
566 info from mangled symbols. GDB can automatically figure out which
567 symbol mangling style your C++ compiler uses.
569 Calling of methods and virtual functions has been improved as well.
573 The crash that occured when debugging Sun Ansi-C compiled binaries is
574 fixed. This was due to mishandling of the extra N_SO stabs output
577 We also finally got Ultrix 4.2 running in house, and fixed core file
578 support, with help from a dozen people on the net.
580 John M. Farrell discovered that the reason that single-stepping was so
581 slow on all of the Mips based platforms (primarily SGI and DEC) was
582 that we were trying to demangle and lookup a symbol used for internal
583 purposes on every instruction that was being stepped through. Changing
584 the name of that symbol so that it couldn't be mistaken for a C++
585 mangled symbol sped things up a great deal.
587 Rich Pixley sped up symbol lookups in general by getting much smarter
588 about when C++ symbol mangling is necessary. This should make symbol
589 completion (TAB on the command line) much faster. It's not as fast as
590 we'd like, but it's significantly faster than gdb-4.6.
594 A new user controllable variable 'call_scratch_address' can
595 specify the location of a scratch area to be used when GDB
596 calls a function in the target. This is necessary because the
597 usual method of putting the scratch area on the stack does not work
598 in systems that have separate instruction and data spaces.
600 We integrated changes to support the 29k UDI (Universal Debugger
601 Interface), but discovered at the last minute that we didn't have all
602 of the appropriate copyright paperwork. We are working with AMD to
603 resolve this, and hope to have it available soon.
607 We have sped up the remote serial line protocol, especially for targets
608 with lots of registers. It now supports a new `expedited status' ('T')
609 message which can be used in place of the existing 'S' status message.
610 This allows the remote stub to send only the registers that GDB
611 needs to make a quick decision about single-stepping or conditional
612 breakpoints, eliminating the need to fetch the entire register set for
613 each instruction being stepped through.
615 The GDB remote serial protocol now implements a write-through cache for
616 registers, only re-reading the registers if the target has run.
618 There is also a new remote serial stub for SPARC processors. You can
619 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
620 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
621 processor with a serial port.
625 Configure.in files have become much easier to read and modify. A new
626 `table driven' format makes it more obvious what configurations are
627 supported, and what files each one uses.
631 There is a new opcodes library which will eventually contain all of the
632 disassembly routines and opcode tables. At present, it only contains
633 Sparc and Z8000 routines. This will allow the assembler, debugger, and
634 disassembler (binutils/objdump) to share these routines.
636 The libiberty library is now copylefted under the GNU Library General
637 Public License. This allows more liberal use, and was done so libg++
638 can use it. This makes no difference to GDB, since the Library License
639 grants all the rights from the General Public License.
643 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
644 reference to the stabs symbol info used by the debugger. It is (as far
645 as we know) the only published document on this fascinating topic. We
646 encourage you to read it, compare it to the stabs information on your
647 system, and send improvements on the document in general (to
648 bug-gdb@prep.ai.mit.edu).
650 And, of course, many bugs have been fixed.
653 *** Changes in GDB-4.6:
655 * Better support for C++ function names
657 GDB now accepts as input the "demangled form" of C++ overloaded function
658 names and member function names, and can do command completion on such names
659 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
660 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
661 Make use of command completion, it is your friend.
663 GDB also now accepts a variety of C++ mangled symbol formats. They are
664 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
665 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
666 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
667 for the list of formats.
669 * G++ symbol mangling problem
671 Recent versions of gcc have a bug in how they emit debugging information for
672 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
673 directory) can be applied to gcc to fix the problem. Alternatively, if you
674 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
675 usual symptom is difficulty with setting breakpoints on methods. GDB complains
676 about the method being non-existent. (We believe that version 2.2.2 of GCC has
679 * New 'maintenance' command
681 All of the commands related to hacking GDB internals have been moved out of
682 the main command set, and now live behind the 'maintenance' command. This
683 can also be abbreviated as 'mt'. The following changes were made:
685 dump-me -> maintenance dump-me
686 info all-breakpoints -> maintenance info breakpoints
687 printmsyms -> maintenance print msyms
688 printobjfiles -> maintenance print objfiles
689 printpsyms -> maintenance print psymbols
690 printsyms -> maintenance print symbols
692 The following commands are new:
694 maintenance demangle Call internal GDB demangler routine to
695 demangle a C++ link name and prints the result.
696 maintenance print type Print a type chain for a given symbol
698 * Change to .gdbinit file processing
700 We now read the $HOME/.gdbinit file before processing the argv arguments
701 (e.g. reading symbol files or core files). This allows global parameters to
702 be set, which will apply during the symbol reading. The ./.gdbinit is still
703 read after argv processing.
705 * New hosts supported
707 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
709 Linux support i386-unknown-linux or linux
711 We are also including code to support the HP/PA running BSD and HPUX. This
712 is almost guaranteed not to work, as we didn't have time to test or build it
713 for this release. We are including it so that the more adventurous (or
714 masochistic) of you can play with it. We also had major problems with the
715 fact that the compiler that we got from HP doesn't support the -g option.
718 * New targets supported
720 Hitachi H8/300 h8300-hitachi-hms or h8300hms
722 * More smarts about finding #include files
724 GDB now remembers the compilation directory for all include files, and for
725 all files from which C is generated (like yacc and lex sources). This
726 greatly improves GDB's ability to find yacc/lex sources, and include files,
727 especially if you are debugging your program from a directory different from
728 the one that contains your sources.
730 We also fixed a bug which caused difficulty with listing and setting
731 breakpoints in include files which contain C code. (In the past, you had to
732 try twice in order to list an include file that you hadn't looked at before.)
734 * Interesting infernals change
736 GDB now deals with arbitrary numbers of sections, where the symbols for each
737 section must be relocated relative to that section's landing place in the
738 target's address space. This work was needed to support ELF with embedded
739 stabs used by Solaris-2.0.
741 * Bug fixes (of course!)
743 There have been loads of fixes for the following things:
744 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
745 i960, stabs, DOS(GO32), procfs, etc...
747 See the ChangeLog for details.
749 *** Changes in GDB-4.5:
751 * New machines supported (host and target)
753 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
755 SGI Irix-4.x mips-sgi-irix4 or iris4
759 GDB now uses a new memory manager called mmalloc, based on gmalloc.
760 Mmalloc is capable of handling mutiple heaps of memory. It is also
761 capable of saving a heap to a file, and then mapping it back in later.
762 This can be used to greatly speedup the startup of GDB by using a
763 pre-parsed symbol table which lives in a mmalloc managed heap. For
764 more details, please read mmalloc/mmalloc.texi.
768 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
769 'help info proc' for details.
771 * MIPS ecoff symbol table format
773 The code that reads MIPS symbol table format is now supported on all hosts.
774 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
777 * File name changes for MS-DOS
779 Many files in the config directories have been renamed to make it easier to
780 support GDB on MS-DOSe systems (which have very restrictive file name
781 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
782 environment) is close to working but has some remaining problems. Note
783 that debugging of DOS programs is not supported, due to limitations
784 in the ``operating system'', but it can be used to host cross-debugging.
786 * Cross byte order fixes
788 Many fixes have been made to support cross debugging of Sparc and MIPS
789 targets from hosts whose byte order differs.
791 * New -mapped and -readnow options
793 If memory-mapped files are available on your system through the 'mmap'
794 system call, you can use the -mapped option on the `file' or
795 `symbol-file' commands to cause GDB to write the symbols from your
796 program into a reusable file. If the program you are debugging is
797 called `/path/fred', the mapped symbol file will be `./fred.syms'.
798 Future GDB debugging sessions will notice the presence of this file,
799 and will quickly map in symbol information from it, rather than reading
800 the symbol table from the executable program. Using the '-mapped'
801 option in a GDB `file' or `symbol-file' command has the same effect as
802 starting GDB with the '-mapped' command-line option.
804 You can cause GDB to read the entire symbol table immediately by using
805 the '-readnow' option with any of the commands that load symbol table
806 information (or on the GDB command line). This makes the command
807 slower, but makes future operations faster.
809 The -mapped and -readnow options are typically combined in order to
810 build a `fred.syms' file that contains complete symbol information.
811 A simple GDB invocation to do nothing but build a `.syms' file for future
814 gdb -batch -nx -mapped -readnow programname
816 The `.syms' file is specific to the host machine on which GDB is run.
817 It holds an exact image of GDB's internal symbol table. It cannot be
818 shared across multiple host platforms.
822 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
823 siglongjmp() without losing control. This feature has not yet been ported to
824 all systems. It currently works on many 386 platforms, all MIPS-based
825 platforms (SGI, DECstation, etc), and Sun3/4.
829 Preliminary work has been put in to support the new Solaris OS from Sun. At
830 this time, it can control and debug processes, but it is not capable of
835 As always, many many bug fixes. The major areas were with g++, and mipsread.
836 People using the MIPS-based platforms should experience fewer mysterious
837 crashes and trashed symbol tables.
839 *** Changes in GDB-4.4:
841 * New machines supported (host and target)
843 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
845 BSD Reno on Vax vax-dec-bsd
846 Ultrix on Vax vax-dec-ultrix
848 * New machines supported (target)
850 AMD 29000 embedded, using EBMON a29k-none-none
854 GDB continues to improve its handling of C++. `References' work better.
855 The demangler has also been improved, and now deals with symbols mangled as
856 per the Annotated C++ Reference Guide.
858 GDB also now handles `stabs' symbol information embedded in MIPS
859 `ecoff' symbol tables. Since the ecoff format was not easily
860 extensible to handle new languages such as C++, this appeared to be a
861 good way to put C++ debugging info into MIPS binaries. This option
862 will be supported in the GNU C compiler, version 2, when it is
865 * New features for SVR4
867 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
868 shared libraries. Debugging dynamically linked programs should present
869 only minor differences from debugging statically linked programs.
871 The `info proc' command will print out information about any process
872 on an SVR4 system (including the one you are debugging). At the moment,
873 it prints the address mappings of the process.
875 If you bring up GDB on another SVR4 system, please send mail to
876 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
878 * Better dynamic linking support in SunOS
880 Reading symbols from shared libraries which contain debugging symbols
881 now works properly. However, there remain issues such as automatic
882 skipping of `transfer vector' code during function calls, which
883 make it harder to debug code in a shared library, than to debug the
884 same code linked statically.
888 GDB is now using the latest `getopt' routines from the FSF. This
889 version accepts the -- prefix for options with long names. GDB will
890 continue to accept the old forms (-option and +option) as well.
891 Various single letter abbreviations for options have been explicity
892 added to the option table so that they won't get overshadowed in the
893 future by other options that begin with the same letter.
897 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
898 Many assorted bugs have been handled. Many more remain to be handled.
899 See the various ChangeLog files (primarily in gdb and bfd) for details.
902 *** Changes in GDB-4.3:
904 * New machines supported (host and target)
906 Amiga 3000 running Amix m68k-cbm-svr4 or amix
907 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
908 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
910 * Almost SCO Unix support
912 We had hoped to support:
913 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
914 (except for core file support), but we discovered very late in the release
915 that it has problems with process groups that render gdb unusable. Sorry
916 about that. I encourage people to fix it and post the fixes.
918 * Preliminary ELF and DWARF support
920 GDB can read ELF object files on System V Release 4, and can handle
921 debugging records for C, in DWARF format, in ELF files. This support
922 is preliminary. If you bring up GDB on another SVR4 system, please
923 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
928 GDB now uses the latest `readline' library. One user-visible change
929 is that two tabs will list possible command completions, which previously
930 required typing M-? (meta-question mark, or ESC ?).
934 The `stepi' bug that many of you noticed has been squashed.
935 Many bugs in C++ have been handled. Many more remain to be handled.
936 See the various ChangeLog files (primarily in gdb and bfd) for details.
938 * State of the MIPS world (in case you wondered):
940 GDB can understand the symbol tables emitted by the compilers
941 supplied by most vendors of MIPS-based machines, including DEC. These
942 symbol tables are in a format that essentially nobody else uses.
944 Some versions of gcc come with an assembler post-processor called
945 mips-tfile. This program is required if you want to do source-level
946 debugging of gcc-compiled programs. I believe FSF does not ship
947 mips-tfile with gcc version 1, but it will eventually come with gcc
950 Debugging of g++ output remains a problem. g++ version 1.xx does not
951 really support it at all. (If you're lucky, you should be able to get
952 line numbers and stack traces to work, but no parameters or local
953 variables.) With some work it should be possible to improve the
956 When gcc version 2 is released, you will have somewhat better luck.
957 However, even then you will get confusing results for inheritance and
960 We will eventually provide full debugging of g++ output on
961 DECstations. This will probably involve some kind of stabs-in-ecoff
962 encapulation, but the details have not been worked out yet.
965 *** Changes in GDB-4.2:
967 * Improved configuration
969 Only one copy of `configure' exists now, and it is not self-modifying.
970 Porting BFD is simpler.
974 The `step' and `next' commands now only stop at the first instruction
975 of a source line. This prevents the multiple stops that used to occur
976 in switch statements, for-loops, etc. `Step' continues to stop if a
977 function that has debugging information is called within the line.
981 Lots of small bugs fixed. More remain.
983 * New host supported (not target)
985 Intel 386 PC clone running Mach i386-none-mach
988 *** Changes in GDB-4.1:
990 * Multiple source language support
992 GDB now has internal scaffolding to handle several source languages.
993 It determines the type of each source file from its filename extension,
994 and will switch expression parsing and number formatting to match the
995 language of the function in the currently selected stack frame.
996 You can also specifically set the language to be used, with
997 `set language c' or `set language modula-2'.
1001 GDB now has preliminary support for the GNU Modula-2 compiler,
1002 currently under development at the State University of New York at
1003 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
1004 continue through the fall of 1991 and into 1992.
1006 Other Modula-2 compilers are currently not supported, and attempting to
1007 debug programs compiled with them will likely result in an error as the
1008 symbol table is read. Feel free to work on it, though!
1010 There are hooks in GDB for strict type checking and range checking,
1011 in the `Modula-2 philosophy', but they do not currently work.
1015 GDB can now write to executable and core files (e.g. patch
1016 a variable's value). You must turn this switch on, specify
1017 the file ("exec foo" or "core foo"), *then* modify it, e.g.
1018 by assigning a new value to a variable. Modifications take
1021 * Automatic SunOS shared library reading
1023 When you run your program, GDB automatically determines where its
1024 shared libraries (if any) have been loaded, and reads their symbols.
1025 The `share' command is no longer needed. This also works when
1026 examining core files.
1030 You can specify the number of lines that the `list' command shows.
1033 * New machines supported (host and target)
1035 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
1036 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
1037 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
1039 * New hosts supported (not targets)
1041 IBM RT/PC: romp-ibm-aix or rtpc
1043 * New targets supported (not hosts)
1045 AMD 29000 embedded with COFF a29k-none-coff
1046 AMD 29000 embedded with a.out a29k-none-aout
1047 Ultracomputer remote kernel debug a29k-nyu-kern
1049 * New remote interfaces
1055 *** Changes in GDB-4.0:
1059 Wide output is wrapped at good places to make the output more readable.
1061 Gdb now supports cross-debugging from a host machine of one type to a
1062 target machine of another type. Communication with the target system
1063 is over serial lines. The ``target'' command handles connecting to the
1064 remote system; the ``load'' command will download a program into the
1065 remote system. Serial stubs for the m68k and i386 are provided. Gdb
1066 also supports debugging of realtime processes running under VxWorks,
1067 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
1068 stub on the target system.
1070 New CPUs supported include the AMD 29000 and Intel 960.
1072 GDB now reads object files and symbol tables via a ``binary file''
1073 library, which allows a single copy of GDB to debug programs of multiple
1074 object file types such as a.out and coff.
1076 There is now a GDB reference card in "doc/refcard.tex". (Make targets
1077 refcard.dvi and refcard.ps are available to format it).
1080 * Control-Variable user interface simplified
1082 All variables that control the operation of the debugger can be set
1083 by the ``set'' command, and displayed by the ``show'' command.
1085 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
1086 ``Show prompt'' produces the response:
1087 Gdb's prompt is new-gdb=>.
1089 What follows are the NEW set commands. The command ``help set'' will
1090 print a complete list of old and new set commands. ``help set FOO''
1091 will give a longer description of the variable FOO. ``show'' will show
1092 all of the variable descriptions and their current settings.
1094 confirm on/off: Enables warning questions for operations that are
1095 hard to recover from, e.g. rerunning the program while
1096 it is already running. Default is ON.
1098 editing on/off: Enables EMACS style command line editing
1099 of input. Previous lines can be recalled with
1100 control-P, the current line can be edited with control-B,
1101 you can search for commands with control-R, etc.
1104 history filename NAME: NAME is where the gdb command history
1105 will be stored. The default is .gdb_history,
1106 or the value of the environment variable
1109 history size N: The size, in commands, of the command history. The
1110 default is 256, or the value of the environment variable
1113 history save on/off: If this value is set to ON, the history file will
1114 be saved after exiting gdb. If set to OFF, the
1115 file will not be saved. The default is OFF.
1117 history expansion on/off: If this value is set to ON, then csh-like
1118 history expansion will be performed on
1119 command line input. The default is OFF.
1121 radix N: Sets the default radix for input and output. It can be set
1122 to 8, 10, or 16. Note that the argument to "radix" is interpreted
1123 in the current radix, so "set radix 10" is always a no-op.
1125 height N: This integer value is the number of lines on a page. Default
1126 is 24, the current `stty rows'' setting, or the ``li#''
1127 setting from the termcap entry matching the environment
1130 width N: This integer value is the number of characters on a line.
1131 Default is 80, the current `stty cols'' setting, or the ``co#''
1132 setting from the termcap entry matching the environment
1135 Note: ``set screensize'' is obsolete. Use ``set height'' and
1136 ``set width'' instead.
1138 print address on/off: Print memory addresses in various command displays,
1139 such as stack traces and structure values. Gdb looks
1140 more ``symbolic'' if you turn this off; it looks more
1141 ``machine level'' with it on. Default is ON.
1143 print array on/off: Prettyprint arrays. New convenient format! Default
1146 print demangle on/off: Print C++ symbols in "source" form if on,
1149 print asm-demangle on/off: Same, for assembler level printouts
1152 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
1155 * Support for Epoch Environment.
1157 The epoch environment is a version of Emacs v18 with windowing. One
1158 new command, ``inspect'', is identical to ``print'', except that if you
1159 are running in the epoch environment, the value is printed in its own
1163 * Support for Shared Libraries
1165 GDB can now debug programs and core files that use SunOS shared libraries.
1166 Symbols from a shared library cannot be referenced
1167 before the shared library has been linked with the program (this
1168 happens after you type ``run'' and before the function main() is entered).
1169 At any time after this linking (including when examining core files
1170 from dynamically linked programs), gdb reads the symbols from each
1171 shared library when you type the ``sharedlibrary'' command.
1172 It can be abbreviated ``share''.
1174 sharedlibrary REGEXP: Load shared object library symbols for files
1175 matching a unix regular expression. No argument
1176 indicates to load symbols for all shared libraries.
1178 info sharedlibrary: Status of loaded shared libraries.
1183 A watchpoint stops execution of a program whenever the value of an
1184 expression changes. Checking for this slows down execution
1185 tremendously whenever you are in the scope of the expression, but is
1186 quite useful for catching tough ``bit-spreader'' or pointer misuse
1187 problems. Some machines such as the 386 have hardware for doing this
1188 more quickly, and future versions of gdb will use this hardware.
1190 watch EXP: Set a watchpoint (breakpoint) for an expression.
1192 info watchpoints: Information about your watchpoints.
1194 delete N: Deletes watchpoint number N (same as breakpoints).
1195 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
1196 enable N: Re-enables watchpoint number N (same as breakpoints).
1199 * C++ multiple inheritance
1201 When used with a GCC version 2 compiler, GDB supports multiple inheritance
1204 * C++ exception handling
1206 Gdb now supports limited C++ exception handling. Besides the existing
1207 ability to breakpoint on an exception handler, gdb can breakpoint on
1208 the raising of an exception (before the stack is peeled back to the
1211 catch FOO: If there is a FOO exception handler in the dynamic scope,
1212 set a breakpoint to catch exceptions which may be raised there.
1213 Multiple exceptions (``catch foo bar baz'') may be caught.
1215 info catch: Lists all exceptions which may be caught in the
1216 current stack frame.
1219 * Minor command changes
1221 The command ``call func (arg, arg, ...)'' now acts like the print
1222 command, except it does not print or save a value if the function's result
1223 is void. This is similar to dbx usage.
1225 The ``up'' and ``down'' commands now always print the frame they end up
1226 at; ``up-silently'' and `down-silently'' can be used in scripts to change
1227 frames without printing.
1229 * New directory command
1231 'dir' now adds directories to the FRONT of the source search path.
1232 The path starts off empty. Source files that contain debug information
1233 about the directory in which they were compiled can be found even
1234 with an empty path; Sun CC and GCC include this information. If GDB can't
1235 find your source file in the current directory, type "dir .".
1237 * Configuring GDB for compilation
1239 For normal use, type ``./configure host''. See README or gdb.texinfo
1242 GDB now handles cross debugging. If you are remotely debugging between
1243 two different machines, type ``./configure host -target=targ''.
1244 Host is the machine where GDB will run; targ is the machine
1245 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob