1 What has changed since GDB-3.5?
2 (Organized release by release)
4 *** Changes in GDB-4.9:
6 (This is a prototype to remind us of things that should be announced
7 in the next release...)
9 'Cfront' style demangling has had its name changed to 'ARM' style, to
10 emphasize that it was written from the specifications in the Annotated
11 Reference Manual, not to be compatible with AT&T cfront. Despite disclaimers,
12 it still generated too much confusion with users attempting to use gdb with
17 GDB now uses a standard remote interface to a simulator library.
18 So far, the library contains simulators for the Zilog Z8001/2, the
19 Hitachi H8/300, H8/500 and Super-H.
21 * New targets supported
23 H8/300 simulator h8300-hitachi-hms or h8300hms
24 H8/500 simulator h8500-hitachi-hms or h8500hms
25 SH simulator sh-hitachi-hms or sh
26 Z8000 simulator z8k-zilog-none or z8ksim
30 Cross-debugging to GO32 targets is supported. It requires a custom
31 version of the i386-stub.c module which is integrated with the
32 GO32 memory extender. Msg follows:
35 Date: Tue, 16 Feb 93 02:34:20 EST
36 From: "Mark W. Eichin" <eichin@cygnus.com>
37 Message-Id: <9302160734.AA09302@tweedledumb.cygnus.com>
39 Cc: ian@cygnus.com, gnu@cygnus.com, gumby@cygnus.com, gdb@cygnus.com
40 In-Reply-To: gnu@cygnus.com's message of Mon, 15 Feb 93 22:30:09 -0800 <9302160630.AA00786@cygnus.com>
41 Subject: GO32 debugging in devo/gdb
43 SUB: GO32 debugging in devo/gdb
44 SUM: <gnu>, gnu->eichin, ian, gnu, gumby, gdb
46 My impression is that devo/gdb supports remote debugging of GO32 programs.
49 Yes. I think that even the 4.7 release had everything needed.
51 What does a user have to have in the GO32 environment in order to do this?
52 (My guess: our custom-modified GO32. Did we send the changes back to
53 DJ and did they ever get integrated into the standard GO32?)
55 I asked DJ if he wanted the changes; at the time, he was very busy
56 having a daughter. He's back on the net now, I'll give him another
57 try. My changes are to GO32 1.07 and the entire source (and an
58 executable) are checked in to cvs; the current GO32 is 1.08, I haven't
59 tried updating the changes.
61 What does a user have to actually do in GO32 in order for this to work?
62 E.g. there seems to be no user-level documentation for this feature.
64 GO32 includes "go32.exe" and "debug32.exe"; my version is
65 "dser32.exe". With a serial link on com1 to the host, use the mode
66 command on the target to set the baud rate, then "dser32 a.out" and
67 start up gdb (configured -target go32), target remote /dev/ttya.
68 Shoudl just work from there.
70 I'm wondering if we can announce this as part of what's supported in
73 The hard part is the extender itself -- it needs to be built with a
74 native 16-bit compiler (such as Turbo C with Turbo Assembler -- about
75 $300 in software, which I do own -- and the assembly code uses enough
76 high level features (like structs) that it isn't portable to other
77 assemblers.) We have no way to build it with any free tools. I think
78 we can ship (or at least make available) the executable for the DOS
79 side, I don't think Turbo C has any runtime restrictions.
83 *** Changes in GDB-4.8:
85 * HP Precision Architecture supported
87 GDB now supports HP PA-RISC machines running HPUX. A preliminary
88 version of this support was available as a set of patches from the
89 University of Utah. GDB does not support debugging of programs
90 compiled with the HP compiler, because HP will not document their file
91 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
92 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
94 Many problems in the preliminary version have been fixed.
96 * Faster and better demangling
98 We have improved template demangling and fixed numerous bugs in the GNU style
99 demangler. It can now handle type modifiers such as `static' or `const'. Wide
100 character types (wchar_t) are now supported. Demangling of each symbol is now
101 only done once, and is cached when the symbol table for a file is read in.
102 This results in a small increase in memory usage for C programs, a moderate
103 increase in memory usage for C++ programs, and a fantastic speedup in
106 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
107 from the specifications in the Annotated Reference Manual, which AT&T's
108 compiler does not actually implement.
110 * G++ multiple inheritance compiler problem
112 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
113 inheritance lattices was reworked to properly discover ambiguities. We
114 recently found an example which causes this new algorithm to fail in a
115 very subtle way, producing bad debug information for those classes.
116 The file 'gcc.patch' (in this directory) can be applied to gcc to
117 circumvent the problem. A future GCC release will contain a complete
120 The previous G++ debug info problem (mentioned below for the gdb-4.7
121 release) is fixed in gcc version 2.3.2.
123 * Improved configure script
125 The `configure' script will now attempt to guess your system type if
126 you don't supply a host system type. The old scheme of supplying a
127 host system triplet is preferable over using this. All the magic is
128 done in the new `config.guess' script. Examine it for details.
130 We have also brought our configure script much more in line with the FSF's
131 version. It now supports the --with-xxx options. In particular,
132 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
133 The resulting GDB will not be able to read arbitrary object file formats --
134 only the format ``expected'' to be used on the configured target system.
135 We hope to make this the default in a future release.
137 * Documentation improvements
139 There's new internal documentation on how to modify GDB, and how to
140 produce clean changes to the code. We implore people to read it
141 before submitting changes.
143 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
144 M4 macros. The new texinfo.tex is provided in this release. Pre-built
145 `info' files are also provided. To build `info' files from scratch,
146 you will need the latest `makeinfo' release, which will be available in
147 a future texinfo-X.Y release.
149 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
150 We're not sure exactly which versions have this problem, but it has
151 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
152 or better. If that isn't possible, there is a patch in
153 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
158 GDB now supports array constants that can be used in expressions typed in by
159 the user. The syntax is `{element, element, ...}'. Ie: you can now type
160 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
163 The new directory `gdb/sparclite' contains a program that demonstrates
164 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
166 * New native hosts supported
168 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
169 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
171 * New targets supported
173 AMD 29k family via UDI a29k-amd-udi or udi29k
175 * New file formats supported
177 BFD now supports reading HP/PA-RISC executables (SOM file format?),
178 HPUX core files, and SCO 3.2v2 core files.
182 Attaching to processes now works again; thanks for the many bug reports.
184 We have also stomped on a bunch of core dumps caused by
185 printf_filtered("%s") problems.
187 We eliminated a copyright problem on the rpc and ptrace header files
188 for VxWorks, which was discovered at the last minute during the 4.7
189 release. You should now be able to build a VxWorks GDB.
191 You can now interrupt gdb while an attached process is running. This
192 will cause the attached process to stop, and give control back to GDB.
194 We fixed problems caused by using too many file descriptors
195 for reading symbols from object files and libraries. This was
196 especially a problem for programs that used many (~100) shared
199 The `step' command now only enters a subroutine if there is line number
200 information for the subroutine. Otherwise it acts like the `next'
201 command. Previously, `step' would enter subroutines if there was
202 any debugging information about the routine. This avoids problems
203 when using `cc -g1' on MIPS machines.
205 * Internal improvements
207 GDB's internal interfaces have been improved to make it easier to support
208 debugging of multiple languages in the future.
210 GDB now uses a common structure for symbol information internally.
211 Minimal symbols (derived from linkage symbols in object files), partial
212 symbols (from a quick scan of debug information), and full symbols
213 contain a common subset of information, making it easier to write
214 shared code that handles any of them.
216 * New command line options
218 We now accept --silent as an alias for --quiet.
222 The memory-mapped-malloc library is now licensed under the GNU Library
223 General Public License.
225 *** Changes in GDB-4.7:
227 * Host/native/target split
229 GDB has had some major internal surgery to untangle the support for
230 hosts and remote targets. Now, when you configure GDB for a remote
231 target, it will no longer load in all of the support for debugging
232 local programs on the host. When fully completed and tested, this will
233 ensure that arbitrary host/target combinations are possible.
235 The primary conceptual shift is to separate the non-portable code in
236 GDB into three categories. Host specific code is required any time GDB
237 is compiled on that host, regardless of the target. Target specific
238 code relates to the peculiarities of the target, but can be compiled on
239 any host. Native specific code is everything else: it can only be
240 built when the host and target are the same system. Child process
241 handling and core file support are two common `native' examples.
243 GDB's use of /proc for controlling Unix child processes is now cleaner.
244 It has been split out into a single module under the `target_ops' vector,
245 plus two native-dependent functions for each system that uses /proc.
247 * New hosts supported
249 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
250 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
251 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
253 * New targets supported
255 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
256 68030 and CPU32 m68030-*-*, m68332-*-*
258 * New native hosts supported
260 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
261 (386bsd is not well tested yet)
262 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
264 * New file formats supported
266 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
267 supports reading of `a.out.adobe' object files, which are an a.out
268 format extended with minimal information about multiple sections.
272 `show copying' is the same as the old `info copying'.
273 `show warranty' is the same as `info warrantee'.
274 These were renamed for consistency. The old commands continue to work.
276 `info handle' is a new alias for `info signals'.
278 You can now define pre-command hooks, which attach arbitrary command
279 scripts to any command. The commands in the hook will be executed
280 prior to the user's command. You can also create a hook which will be
281 executed whenever the program stops. See gdb.texinfo.
285 We now deal with Cfront style name mangling, and can even extract type
286 info from mangled symbols. GDB can automatically figure out which
287 symbol mangling style your C++ compiler uses.
289 Calling of methods and virtual functions has been improved as well.
293 The crash that occured when debugging Sun Ansi-C compiled binaries is
294 fixed. This was due to mishandling of the extra N_SO stabs output
297 We also finally got Ultrix 4.2 running in house, and fixed core file
298 support, with help from a dozen people on the net.
300 John M. Farrell discovered that the reason that single-stepping was so
301 slow on all of the Mips based platforms (primarily SGI and DEC) was
302 that we were trying to demangle and lookup a symbol used for internal
303 purposes on every instruction that was being stepped through. Changing
304 the name of that symbol so that it couldn't be mistaken for a C++
305 mangled symbol sped things up a great deal.
307 Rich Pixley sped up symbol lookups in general by getting much smarter
308 about when C++ symbol mangling is necessary. This should make symbol
309 completion (TAB on the command line) much faster. It's not as fast as
310 we'd like, but it's significantly faster than gdb-4.6.
314 A new user controllable variable 'call_scratch_address' can
315 specify the location of a scratch area to be used when GDB
316 calls a function in the target. This is necessary because the
317 usual method of putting the scratch area on the stack does not work
318 in systems that have separate instruction and data spaces.
320 We integrated changes to support the 29k UDI (Universal Debugger
321 Interface), but discovered at the last minute that we didn't have all
322 of the appropriate copyright paperwork. We are working with AMD to
323 resolve this, and hope to have it available soon.
327 We have sped up the remote serial line protocol, especially for targets
328 with lots of registers. It now supports a new `expedited status' ('T')
329 message which can be used in place of the existing 'S' status message.
330 This allows the remote stub to send only the registers that GDB
331 needs to make a quick decision about single-stepping or conditional
332 breakpoints, eliminating the need to fetch the entire register set for
333 each instruction being stepped through.
335 The GDB remote serial protocol now implements a write-through cache for
336 registers, only re-reading the registers if the target has run.
338 There is also a new remote serial stub for SPARC processors. You can
339 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
340 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
341 processor with a serial port.
345 Configure.in files have become much easier to read and modify. A new
346 `table driven' format makes it more obvious what configurations are
347 supported, and what files each one uses.
351 There is a new opcodes library which will eventually contain all of the
352 disassembly routines and opcode tables. At present, it only contains
353 Sparc and Z8000 routines. This will allow the assembler, debugger, and
354 disassembler (binutils/objdump) to share these routines.
356 The libiberty library is now copylefted under the GNU Library General
357 Public License. This allows more liberal use, and was done so libg++
358 can use it. This makes no difference to GDB, since the Library License
359 grants all the rights from the General Public License.
363 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
364 reference to the stabs symbol info used by the debugger. It is (as far
365 as we know) the only published document on this fascinating topic. We
366 encourage you to read it, compare it to the stabs information on your
367 system, and send improvements on the document in general (to
368 bug-gdb@prep.ai.mit.edu).
370 And, of course, many bugs have been fixed.
373 *** Changes in GDB-4.6:
375 * Better support for C++ function names
377 GDB now accepts as input the "demangled form" of C++ overloaded function
378 names and member function names, and can do command completion on such names
379 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
380 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
381 Make use of command completion, it is your friend.
383 GDB also now accepts a variety of C++ mangled symbol formats. They are
384 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
385 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
386 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
387 for the list of formats.
389 * G++ symbol mangling problem
391 Recent versions of gcc have a bug in how they emit debugging information for
392 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
393 directory) can be applied to gcc to fix the problem. Alternatively, if you
394 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
395 usual symptom is difficulty with setting breakpoints on methods. GDB complains
396 about the method being non-existent. (We believe that version 2.2.2 of GCC has
399 * New 'maintenance' command
401 All of the commands related to hacking GDB internals have been moved out of
402 the main command set, and now live behind the 'maintenance' command. This
403 can also be abbreviated as 'mt'. The following changes were made:
405 dump-me -> maintenance dump-me
406 info all-breakpoints -> maintenance info breakpoints
407 printmsyms -> maintenance print msyms
408 printobjfiles -> maintenance print objfiles
409 printpsyms -> maintenance print psymbols
410 printsyms -> maintenance print symbols
412 The following commands are new:
414 maintenance demangle Call internal GDB demangler routine to
415 demangle a C++ link name and prints the result.
416 maintenance print type Print a type chain for a given symbol
418 * Change to .gdbinit file processing
420 We now read the $HOME/.gdbinit file before processing the argv arguments
421 (e.g. reading symbol files or core files). This allows global parameters to
422 be set, which will apply during the symbol reading. The ./.gdbinit is still
423 read after argv processing.
425 * New hosts supported
427 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
429 Linux support i386-unknown-linux or linux
431 We are also including code to support the HP/PA running BSD and HPUX. This
432 is almost guaranteed not to work, as we didn't have time to test or build it
433 for this release. We are including it so that the more adventurous (or
434 masochistic) of you can play with it. We also had major problems with the
435 fact that the compiler that we got from HP doesn't support the -g option.
438 * New targets supported
440 Hitachi H8/300 h8300-hitachi-hms or h8300hms
442 * More smarts about finding #include files
444 GDB now remembers the compilation directory for all include files, and for
445 all files from which C is generated (like yacc and lex sources). This
446 greatly improves GDB's ability to find yacc/lex sources, and include files,
447 especially if you are debugging your program from a directory different from
448 the one that contains your sources.
450 We also fixed a bug which caused difficulty with listing and setting
451 breakpoints in include files which contain C code. (In the past, you had to
452 try twice in order to list an include file that you hadn't looked at before.)
454 * Interesting infernals change
456 GDB now deals with arbitrary numbers of sections, where the symbols for each
457 section must be relocated relative to that section's landing place in the
458 target's address space. This work was needed to support ELF with embedded
459 stabs used by Solaris-2.0.
461 * Bug fixes (of course!)
463 There have been loads of fixes for the following things:
464 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
465 i960, stabs, DOS(GO32), procfs, etc...
467 See the ChangeLog for details.
469 *** Changes in GDB-4.5:
471 * New machines supported (host and target)
473 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
475 SGI Irix-4.x mips-sgi-irix4 or iris4
479 GDB now uses a new memory manager called mmalloc, based on gmalloc.
480 Mmalloc is capable of handling mutiple heaps of memory. It is also
481 capable of saving a heap to a file, and then mapping it back in later.
482 This can be used to greatly speedup the startup of GDB by using a
483 pre-parsed symbol table which lives in a mmalloc managed heap. For
484 more details, please read mmalloc/mmalloc.texi.
488 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
489 'help info proc' for details.
491 * MIPS ecoff symbol table format
493 The code that reads MIPS symbol table format is now supported on all hosts.
494 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
497 * File name changes for MS-DOS
499 Many files in the config directories have been renamed to make it easier to
500 support GDB on MS-DOSe systems (which have very restrictive file name
501 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
502 environment) is close to working but has some remaining problems. Note
503 that debugging of DOS programs is not supported, due to limitations
504 in the ``operating system'', but it can be used to host cross-debugging.
506 * Cross byte order fixes
508 Many fixes have been made to support cross debugging of Sparc and MIPS
509 targets from hosts whose byte order differs.
511 * New -mapped and -readnow options
513 If memory-mapped files are available on your system through the 'mmap'
514 system call, you can use the -mapped option on the `file' or
515 `symbol-file' commands to cause GDB to write the symbols from your
516 program into a reusable file. If the program you are debugging is
517 called `/path/fred', the mapped symbol file will be `./fred.syms'.
518 Future GDB debugging sessions will notice the presence of this file,
519 and will quickly map in symbol information from it, rather than reading
520 the symbol table from the executable program. Using the '-mapped'
521 option in a GDB `file' or `symbol-file' command has the same effect as
522 starting GDB with the '-mapped' command-line option.
524 You can cause GDB to read the entire symbol table immediately by using
525 the '-readnow' option with any of the commands that load symbol table
526 information (or on the GDB command line). This makes the command
527 slower, but makes future operations faster.
529 The -mapped and -readnow options are typically combined in order to
530 build a `fred.syms' file that contains complete symbol information.
531 A simple GDB invocation to do nothing but build a `.syms' file for future
534 gdb -batch -nx -mapped -readnow programname
536 The `.syms' file is specific to the host machine on which GDB is run.
537 It holds an exact image of GDB's internal symbol table. It cannot be
538 shared across multiple host platforms.
542 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
543 siglongjmp() without losing control. This feature has not yet been ported to
544 all systems. It currently works on many 386 platforms, all MIPS-based
545 platforms (SGI, DECstation, etc), and Sun3/4.
549 Preliminary work has been put in to support the new Solaris OS from Sun. At
550 this time, it can control and debug processes, but it is not capable of
555 As always, many many bug fixes. The major areas were with g++, and mipsread.
556 People using the MIPS-based platforms should experience fewer mysterious
557 crashes and trashed symbol tables.
559 *** Changes in GDB-4.4:
561 * New machines supported (host and target)
563 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
565 BSD Reno on Vax vax-dec-bsd
566 Ultrix on Vax vax-dec-ultrix
568 * New machines supported (target)
570 AMD 29000 embedded, using EBMON a29k-none-none
574 GDB continues to improve its handling of C++. `References' work better.
575 The demangler has also been improved, and now deals with symbols mangled as
576 per the Annotated C++ Reference Guide.
578 GDB also now handles `stabs' symbol information embedded in MIPS
579 `ecoff' symbol tables. Since the ecoff format was not easily
580 extensible to handle new languages such as C++, this appeared to be a
581 good way to put C++ debugging info into MIPS binaries. This option
582 will be supported in the GNU C compiler, version 2, when it is
585 * New features for SVR4
587 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
588 shared libraries. Debugging dynamically linked programs should present
589 only minor differences from debugging statically linked programs.
591 The `info proc' command will print out information about any process
592 on an SVR4 system (including the one you are debugging). At the moment,
593 it prints the address mappings of the process.
595 If you bring up GDB on another SVR4 system, please send mail to
596 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
598 * Better dynamic linking support in SunOS
600 Reading symbols from shared libraries which contain debugging symbols
601 now works properly. However, there remain issues such as automatic
602 skipping of `transfer vector' code during function calls, which
603 make it harder to debug code in a shared library, than to debug the
604 same code linked statically.
608 GDB is now using the latest `getopt' routines from the FSF. This
609 version accepts the -- prefix for options with long names. GDB will
610 continue to accept the old forms (-option and +option) as well.
611 Various single letter abbreviations for options have been explicity
612 added to the option table so that they won't get overshadowed in the
613 future by other options that begin with the same letter.
617 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
618 Many assorted bugs have been handled. Many more remain to be handled.
619 See the various ChangeLog files (primarily in gdb and bfd) for details.
622 *** Changes in GDB-4.3:
624 * New machines supported (host and target)
626 Amiga 3000 running Amix m68k-cbm-svr4 or amix
627 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
628 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
630 * Almost SCO Unix support
632 We had hoped to support:
633 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
634 (except for core file support), but we discovered very late in the release
635 that it has problems with process groups that render gdb unusable. Sorry
636 about that. I encourage people to fix it and post the fixes.
638 * Preliminary ELF and DWARF support
640 GDB can read ELF object files on System V Release 4, and can handle
641 debugging records for C, in DWARF format, in ELF files. This support
642 is preliminary. If you bring up GDB on another SVR4 system, please
643 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
648 GDB now uses the latest `readline' library. One user-visible change
649 is that two tabs will list possible command completions, which previously
650 required typing M-? (meta-question mark, or ESC ?).
654 The `stepi' bug that many of you noticed has been squashed.
655 Many bugs in C++ have been handled. Many more remain to be handled.
656 See the various ChangeLog files (primarily in gdb and bfd) for details.
658 * State of the MIPS world (in case you wondered):
660 GDB can understand the symbol tables emitted by the compilers
661 supplied by most vendors of MIPS-based machines, including DEC. These
662 symbol tables are in a format that essentially nobody else uses.
664 Some versions of gcc come with an assembler post-processor called
665 mips-tfile. This program is required if you want to do source-level
666 debugging of gcc-compiled programs. I believe FSF does not ship
667 mips-tfile with gcc version 1, but it will eventually come with gcc
670 Debugging of g++ output remains a problem. g++ version 1.xx does not
671 really support it at all. (If you're lucky, you should be able to get
672 line numbers and stack traces to work, but no parameters or local
673 variables.) With some work it should be possible to improve the
676 When gcc version 2 is released, you will have somewhat better luck.
677 However, even then you will get confusing results for inheritance and
680 We will eventually provide full debugging of g++ output on
681 DECstations. This will probably involve some kind of stabs-in-ecoff
682 encapulation, but the details have not been worked out yet.
685 *** Changes in GDB-4.2:
687 * Improved configuration
689 Only one copy of `configure' exists now, and it is not self-modifying.
690 Porting BFD is simpler.
694 The `step' and `next' commands now only stop at the first instruction
695 of a source line. This prevents the multiple stops that used to occur
696 in switch statements, for-loops, etc. `Step' continues to stop if a
697 function that has debugging information is called within the line.
701 Lots of small bugs fixed. More remain.
703 * New host supported (not target)
705 Intel 386 PC clone running Mach i386-none-mach
708 *** Changes in GDB-4.1:
710 * Multiple source language support
712 GDB now has internal scaffolding to handle several source languages.
713 It determines the type of each source file from its filename extension,
714 and will switch expression parsing and number formatting to match the
715 language of the function in the currently selected stack frame.
716 You can also specifically set the language to be used, with
717 `set language c' or `set language modula-2'.
721 GDB now has preliminary support for the GNU Modula-2 compiler,
722 currently under development at the State University of New York at
723 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
724 continue through the fall of 1991 and into 1992.
726 Other Modula-2 compilers are currently not supported, and attempting to
727 debug programs compiled with them will likely result in an error as the
728 symbol table is read. Feel free to work on it, though!
730 There are hooks in GDB for strict type checking and range checking,
731 in the `Modula-2 philosophy', but they do not currently work.
735 GDB can now write to executable and core files (e.g. patch
736 a variable's value). You must turn this switch on, specify
737 the file ("exec foo" or "core foo"), *then* modify it, e.g.
738 by assigning a new value to a variable. Modifications take
741 * Automatic SunOS shared library reading
743 When you run your program, GDB automatically determines where its
744 shared libraries (if any) have been loaded, and reads their symbols.
745 The `share' command is no longer needed. This also works when
746 examining core files.
750 You can specify the number of lines that the `list' command shows.
753 * New machines supported (host and target)
755 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
756 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
757 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
759 * New hosts supported (not targets)
761 IBM RT/PC: romp-ibm-aix or rtpc
763 * New targets supported (not hosts)
765 AMD 29000 embedded with COFF a29k-none-coff
766 AMD 29000 embedded with a.out a29k-none-aout
767 Ultracomputer remote kernel debug a29k-nyu-kern
769 * New remote interfaces
775 *** Changes in GDB-4.0:
779 Wide output is wrapped at good places to make the output more readable.
781 Gdb now supports cross-debugging from a host machine of one type to a
782 target machine of another type. Communication with the target system
783 is over serial lines. The ``target'' command handles connecting to the
784 remote system; the ``load'' command will download a program into the
785 remote system. Serial stubs for the m68k and i386 are provided. Gdb
786 also supports debugging of realtime processes running under VxWorks,
787 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
788 stub on the target system.
790 New CPUs supported include the AMD 29000 and Intel 960.
792 GDB now reads object files and symbol tables via a ``binary file''
793 library, which allows a single copy of GDB to debug programs of multiple
794 object file types such as a.out and coff.
796 There is now a GDB reference card in "doc/refcard.tex". (Make targets
797 refcard.dvi and refcard.ps are available to format it).
800 * Control-Variable user interface simplified
802 All variables that control the operation of the debugger can be set
803 by the ``set'' command, and displayed by the ``show'' command.
805 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
806 ``Show prompt'' produces the response:
807 Gdb's prompt is new-gdb=>.
809 What follows are the NEW set commands. The command ``help set'' will
810 print a complete list of old and new set commands. ``help set FOO''
811 will give a longer description of the variable FOO. ``show'' will show
812 all of the variable descriptions and their current settings.
814 confirm on/off: Enables warning questions for operations that are
815 hard to recover from, e.g. rerunning the program while
816 it is already running. Default is ON.
818 editing on/off: Enables EMACS style command line editing
819 of input. Previous lines can be recalled with
820 control-P, the current line can be edited with control-B,
821 you can search for commands with control-R, etc.
824 history filename NAME: NAME is where the gdb command history
825 will be stored. The default is .gdb_history,
826 or the value of the environment variable
829 history size N: The size, in commands, of the command history. The
830 default is 256, or the value of the environment variable
833 history save on/off: If this value is set to ON, the history file will
834 be saved after exiting gdb. If set to OFF, the
835 file will not be saved. The default is OFF.
837 history expansion on/off: If this value is set to ON, then csh-like
838 history expansion will be performed on
839 command line input. The default is OFF.
841 radix N: Sets the default radix for input and output. It can be set
842 to 8, 10, or 16. Note that the argument to "radix" is interpreted
843 in the current radix, so "set radix 10" is always a no-op.
845 height N: This integer value is the number of lines on a page. Default
846 is 24, the current `stty rows'' setting, or the ``li#''
847 setting from the termcap entry matching the environment
850 width N: This integer value is the number of characters on a line.
851 Default is 80, the current `stty cols'' setting, or the ``co#''
852 setting from the termcap entry matching the environment
855 Note: ``set screensize'' is obsolete. Use ``set height'' and
856 ``set width'' instead.
858 print address on/off: Print memory addresses in various command displays,
859 such as stack traces and structure values. Gdb looks
860 more ``symbolic'' if you turn this off; it looks more
861 ``machine level'' with it on. Default is ON.
863 print array on/off: Prettyprint arrays. New convenient format! Default
866 print demangle on/off: Print C++ symbols in "source" form if on,
869 print asm-demangle on/off: Same, for assembler level printouts
872 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
875 * Support for Epoch Environment.
877 The epoch environment is a version of Emacs v18 with windowing. One
878 new command, ``inspect'', is identical to ``print'', except that if you
879 are running in the epoch environment, the value is printed in its own
883 * Support for Shared Libraries
885 GDB can now debug programs and core files that use SunOS shared libraries.
886 Symbols from a shared library cannot be referenced
887 before the shared library has been linked with the program (this
888 happens after you type ``run'' and before the function main() is entered).
889 At any time after this linking (including when examining core files
890 from dynamically linked programs), gdb reads the symbols from each
891 shared library when you type the ``sharedlibrary'' command.
892 It can be abbreviated ``share''.
894 sharedlibrary REGEXP: Load shared object library symbols for files
895 matching a unix regular expression. No argument
896 indicates to load symbols for all shared libraries.
898 info sharedlibrary: Status of loaded shared libraries.
903 A watchpoint stops execution of a program whenever the value of an
904 expression changes. Checking for this slows down execution
905 tremendously whenever you are in the scope of the expression, but is
906 quite useful for catching tough ``bit-spreader'' or pointer misuse
907 problems. Some machines such as the 386 have hardware for doing this
908 more quickly, and future versions of gdb will use this hardware.
910 watch EXP: Set a watchpoint (breakpoint) for an expression.
912 info watchpoints: Information about your watchpoints.
914 delete N: Deletes watchpoint number N (same as breakpoints).
915 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
916 enable N: Re-enables watchpoint number N (same as breakpoints).
919 * C++ multiple inheritance
921 When used with a GCC version 2 compiler, GDB supports multiple inheritance
924 * C++ exception handling
926 Gdb now supports limited C++ exception handling. Besides the existing
927 ability to breakpoint on an exception handler, gdb can breakpoint on
928 the raising of an exception (before the stack is peeled back to the
931 catch FOO: If there is a FOO exception handler in the dynamic scope,
932 set a breakpoint to catch exceptions which may be raised there.
933 Multiple exceptions (``catch foo bar baz'') may be caught.
935 info catch: Lists all exceptions which may be caught in the
939 * Minor command changes
941 The command ``call func (arg, arg, ...)'' now acts like the print
942 command, except it does not print or save a value if the function's result
943 is void. This is similar to dbx usage.
945 The ``up'' and ``down'' commands now always print the frame they end up
946 at; ``up-silently'' and `down-silently'' can be used in scripts to change
947 frames without printing.
949 * New directory command
951 'dir' now adds directories to the FRONT of the source search path.
952 The path starts off empty. Source files that contain debug information
953 about the directory in which they were compiled can be found even
954 with an empty path; Sun CC and GCC include this information. If GDB can't
955 find your source file in the current directory, type "dir .".
957 * Configuring GDB for compilation
959 For normal use, type ``./configure host''. See README or gdb.texinfo
962 GDB now handles cross debugging. If you are remotely debugging between
963 two different machines, type ``./configure host -target=targ''.
964 Host is the machine where GDB will run; targ is the machine
965 where the program that you are debugging will run.
projects / binutils-gdb.git / blob