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...)
11 This is the first GDB release which is accompanied by a matching testsuite.
12 The testsuite requires installation of dejagnu, which should be available
13 via ftp from most sites that carry GNU software.
17 'Cfront' style demangling has had its name changed to 'ARM' style, to
18 emphasize that it was written from the specifications in the Annotated
19 Reference Manual, not to be compatible with AT&T cfront. Despite disclaimers,
20 it still generated too much confusion with users attempting to use gdb with
25 GDB now uses a standard remote interface to a simulator library.
26 So far, the library contains simulators for the Zilog Z8001/2, the
27 Hitachi H8/300, H8/500 and Super-H.
29 * New targets supported
31 H8/300 simulator h8300-hitachi-hms or h8300hms
32 H8/500 simulator h8500-hitachi-hms or h8500hms
33 SH simulator sh-hitachi-hms or sh
34 Z8000 simulator z8k-zilog-none or z8ksim
35 IDT MIPS board over serial line mips-idt-ecoff
38 Cross-debugging to GO32 targets is supported. It requires a custom
39 version of the i386-stub.c module which is integrated with the
40 GO32 memory extender. Msg follows:
43 Date: Tue, 16 Feb 93 02:34:20 EST
44 From: "Mark W. Eichin" <eichin@cygnus.com>
45 Message-Id: <9302160734.AA09302@tweedledumb.cygnus.com>
47 Cc: ian@cygnus.com, gnu@cygnus.com, gumby@cygnus.com, gdb@cygnus.com
48 In-Reply-To: gnu@cygnus.com's message of Mon, 15 Feb 93 22:30:09 -0800 <9302160630.AA00786@cygnus.com>
49 Subject: GO32 debugging in devo/gdb
51 SUB: GO32 debugging in devo/gdb
52 SUM: <gnu>, gnu->eichin, ian, gnu, gumby, gdb
54 My impression is that devo/gdb supports remote debugging of GO32 programs.
57 Yes. I think that even the 4.7 release had everything needed.
59 What does a user have to have in the GO32 environment in order to do this?
60 (My guess: our custom-modified GO32. Did we send the changes back to
61 DJ and did they ever get integrated into the standard GO32?)
63 I asked DJ if he wanted the changes; at the time, he was very busy
64 having a daughter. He's back on the net now, I'll give him another
65 try. My changes are to GO32 1.07 and the entire source (and an
66 executable) are checked in to cvs; the current GO32 is 1.08, I haven't
67 tried updating the changes.
69 What does a user have to actually do in GO32 in order for this to work?
70 E.g. there seems to be no user-level documentation for this feature.
72 GO32 includes "go32.exe" and "debug32.exe"; my version is
73 "dser32.exe". With a serial link on com1 to the host, use the mode
74 command on the target to set the baud rate, then "dser32 a.out" and
75 start up gdb (configured -target go32), target remote /dev/ttya.
76 Shoudl just work from there.
78 I'm wondering if we can announce this as part of what's supported in
81 The hard part is the extender itself -- it needs to be built with a
82 native 16-bit compiler (such as Turbo C with Turbo Assembler -- about
83 $300 in software, which I do own -- and the assembly code uses enough
84 high level features (like structs) that it isn't portable to other
85 assemblers.) We have no way to build it with any free tools. I think
86 we can ship (or at least make available) the executable for the DOS
87 side, I don't think Turbo C has any runtime restrictions.
91 *** Changes in GDB-4.8:
93 * HP Precision Architecture supported
95 GDB now supports HP PA-RISC machines running HPUX. A preliminary
96 version of this support was available as a set of patches from the
97 University of Utah. GDB does not support debugging of programs
98 compiled with the HP compiler, because HP will not document their file
99 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
100 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
102 Many problems in the preliminary version have been fixed.
104 * Faster and better demangling
106 We have improved template demangling and fixed numerous bugs in the GNU style
107 demangler. It can now handle type modifiers such as `static' or `const'. Wide
108 character types (wchar_t) are now supported. Demangling of each symbol is now
109 only done once, and is cached when the symbol table for a file is read in.
110 This results in a small increase in memory usage for C programs, a moderate
111 increase in memory usage for C++ programs, and a fantastic speedup in
114 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
115 from the specifications in the Annotated Reference Manual, which AT&T's
116 compiler does not actually implement.
118 * G++ multiple inheritance compiler problem
120 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
121 inheritance lattices was reworked to properly discover ambiguities. We
122 recently found an example which causes this new algorithm to fail in a
123 very subtle way, producing bad debug information for those classes.
124 The file 'gcc.patch' (in this directory) can be applied to gcc to
125 circumvent the problem. A future GCC release will contain a complete
128 The previous G++ debug info problem (mentioned below for the gdb-4.7
129 release) is fixed in gcc version 2.3.2.
131 * Improved configure script
133 The `configure' script will now attempt to guess your system type if
134 you don't supply a host system type. The old scheme of supplying a
135 host system triplet is preferable over using this. All the magic is
136 done in the new `config.guess' script. Examine it for details.
138 We have also brought our configure script much more in line with the FSF's
139 version. It now supports the --with-xxx options. In particular,
140 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
141 The resulting GDB will not be able to read arbitrary object file formats --
142 only the format ``expected'' to be used on the configured target system.
143 We hope to make this the default in a future release.
145 * Documentation improvements
147 There's new internal documentation on how to modify GDB, and how to
148 produce clean changes to the code. We implore people to read it
149 before submitting changes.
151 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
152 M4 macros. The new texinfo.tex is provided in this release. Pre-built
153 `info' files are also provided. To build `info' files from scratch,
154 you will need the latest `makeinfo' release, which will be available in
155 a future texinfo-X.Y release.
157 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
158 We're not sure exactly which versions have this problem, but it has
159 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
160 or better. If that isn't possible, there is a patch in
161 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
166 GDB now supports array constants that can be used in expressions typed in by
167 the user. The syntax is `{element, element, ...}'. Ie: you can now type
168 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
171 The new directory `gdb/sparclite' contains a program that demonstrates
172 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
174 * New native hosts supported
176 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
177 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
179 * New targets supported
181 AMD 29k family via UDI a29k-amd-udi or udi29k
183 * New file formats supported
185 BFD now supports reading HP/PA-RISC executables (SOM file format?),
186 HPUX core files, and SCO 3.2v2 core files.
190 Attaching to processes now works again; thanks for the many bug reports.
192 We have also stomped on a bunch of core dumps caused by
193 printf_filtered("%s") problems.
195 We eliminated a copyright problem on the rpc and ptrace header files
196 for VxWorks, which was discovered at the last minute during the 4.7
197 release. You should now be able to build a VxWorks GDB.
199 You can now interrupt gdb while an attached process is running. This
200 will cause the attached process to stop, and give control back to GDB.
202 We fixed problems caused by using too many file descriptors
203 for reading symbols from object files and libraries. This was
204 especially a problem for programs that used many (~100) shared
207 The `step' command now only enters a subroutine if there is line number
208 information for the subroutine. Otherwise it acts like the `next'
209 command. Previously, `step' would enter subroutines if there was
210 any debugging information about the routine. This avoids problems
211 when using `cc -g1' on MIPS machines.
213 * Internal improvements
215 GDB's internal interfaces have been improved to make it easier to support
216 debugging of multiple languages in the future.
218 GDB now uses a common structure for symbol information internally.
219 Minimal symbols (derived from linkage symbols in object files), partial
220 symbols (from a quick scan of debug information), and full symbols
221 contain a common subset of information, making it easier to write
222 shared code that handles any of them.
224 * New command line options
226 We now accept --silent as an alias for --quiet.
230 The memory-mapped-malloc library is now licensed under the GNU Library
231 General Public License.
233 *** Changes in GDB-4.7:
235 * Host/native/target split
237 GDB has had some major internal surgery to untangle the support for
238 hosts and remote targets. Now, when you configure GDB for a remote
239 target, it will no longer load in all of the support for debugging
240 local programs on the host. When fully completed and tested, this will
241 ensure that arbitrary host/target combinations are possible.
243 The primary conceptual shift is to separate the non-portable code in
244 GDB into three categories. Host specific code is required any time GDB
245 is compiled on that host, regardless of the target. Target specific
246 code relates to the peculiarities of the target, but can be compiled on
247 any host. Native specific code is everything else: it can only be
248 built when the host and target are the same system. Child process
249 handling and core file support are two common `native' examples.
251 GDB's use of /proc for controlling Unix child processes is now cleaner.
252 It has been split out into a single module under the `target_ops' vector,
253 plus two native-dependent functions for each system that uses /proc.
255 * New hosts supported
257 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
258 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
259 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
261 * New targets supported
263 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
264 68030 and CPU32 m68030-*-*, m68332-*-*
266 * New native hosts supported
268 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
269 (386bsd is not well tested yet)
270 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
272 * New file formats supported
274 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
275 supports reading of `a.out.adobe' object files, which are an a.out
276 format extended with minimal information about multiple sections.
280 `show copying' is the same as the old `info copying'.
281 `show warranty' is the same as `info warrantee'.
282 These were renamed for consistency. The old commands continue to work.
284 `info handle' is a new alias for `info signals'.
286 You can now define pre-command hooks, which attach arbitrary command
287 scripts to any command. The commands in the hook will be executed
288 prior to the user's command. You can also create a hook which will be
289 executed whenever the program stops. See gdb.texinfo.
293 We now deal with Cfront style name mangling, and can even extract type
294 info from mangled symbols. GDB can automatically figure out which
295 symbol mangling style your C++ compiler uses.
297 Calling of methods and virtual functions has been improved as well.
301 The crash that occured when debugging Sun Ansi-C compiled binaries is
302 fixed. This was due to mishandling of the extra N_SO stabs output
305 We also finally got Ultrix 4.2 running in house, and fixed core file
306 support, with help from a dozen people on the net.
308 John M. Farrell discovered that the reason that single-stepping was so
309 slow on all of the Mips based platforms (primarily SGI and DEC) was
310 that we were trying to demangle and lookup a symbol used for internal
311 purposes on every instruction that was being stepped through. Changing
312 the name of that symbol so that it couldn't be mistaken for a C++
313 mangled symbol sped things up a great deal.
315 Rich Pixley sped up symbol lookups in general by getting much smarter
316 about when C++ symbol mangling is necessary. This should make symbol
317 completion (TAB on the command line) much faster. It's not as fast as
318 we'd like, but it's significantly faster than gdb-4.6.
322 A new user controllable variable 'call_scratch_address' can
323 specify the location of a scratch area to be used when GDB
324 calls a function in the target. This is necessary because the
325 usual method of putting the scratch area on the stack does not work
326 in systems that have separate instruction and data spaces.
328 We integrated changes to support the 29k UDI (Universal Debugger
329 Interface), but discovered at the last minute that we didn't have all
330 of the appropriate copyright paperwork. We are working with AMD to
331 resolve this, and hope to have it available soon.
335 We have sped up the remote serial line protocol, especially for targets
336 with lots of registers. It now supports a new `expedited status' ('T')
337 message which can be used in place of the existing 'S' status message.
338 This allows the remote stub to send only the registers that GDB
339 needs to make a quick decision about single-stepping or conditional
340 breakpoints, eliminating the need to fetch the entire register set for
341 each instruction being stepped through.
343 The GDB remote serial protocol now implements a write-through cache for
344 registers, only re-reading the registers if the target has run.
346 There is also a new remote serial stub for SPARC processors. You can
347 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
348 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
349 processor with a serial port.
353 Configure.in files have become much easier to read and modify. A new
354 `table driven' format makes it more obvious what configurations are
355 supported, and what files each one uses.
359 There is a new opcodes library which will eventually contain all of the
360 disassembly routines and opcode tables. At present, it only contains
361 Sparc and Z8000 routines. This will allow the assembler, debugger, and
362 disassembler (binutils/objdump) to share these routines.
364 The libiberty library is now copylefted under the GNU Library General
365 Public License. This allows more liberal use, and was done so libg++
366 can use it. This makes no difference to GDB, since the Library License
367 grants all the rights from the General Public License.
371 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
372 reference to the stabs symbol info used by the debugger. It is (as far
373 as we know) the only published document on this fascinating topic. We
374 encourage you to read it, compare it to the stabs information on your
375 system, and send improvements on the document in general (to
376 bug-gdb@prep.ai.mit.edu).
378 And, of course, many bugs have been fixed.
381 *** Changes in GDB-4.6:
383 * Better support for C++ function names
385 GDB now accepts as input the "demangled form" of C++ overloaded function
386 names and member function names, and can do command completion on such names
387 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
388 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
389 Make use of command completion, it is your friend.
391 GDB also now accepts a variety of C++ mangled symbol formats. They are
392 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
393 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
394 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
395 for the list of formats.
397 * G++ symbol mangling problem
399 Recent versions of gcc have a bug in how they emit debugging information for
400 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
401 directory) can be applied to gcc to fix the problem. Alternatively, if you
402 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
403 usual symptom is difficulty with setting breakpoints on methods. GDB complains
404 about the method being non-existent. (We believe that version 2.2.2 of GCC has
407 * New 'maintenance' command
409 All of the commands related to hacking GDB internals have been moved out of
410 the main command set, and now live behind the 'maintenance' command. This
411 can also be abbreviated as 'mt'. The following changes were made:
413 dump-me -> maintenance dump-me
414 info all-breakpoints -> maintenance info breakpoints
415 printmsyms -> maintenance print msyms
416 printobjfiles -> maintenance print objfiles
417 printpsyms -> maintenance print psymbols
418 printsyms -> maintenance print symbols
420 The following commands are new:
422 maintenance demangle Call internal GDB demangler routine to
423 demangle a C++ link name and prints the result.
424 maintenance print type Print a type chain for a given symbol
426 * Change to .gdbinit file processing
428 We now read the $HOME/.gdbinit file before processing the argv arguments
429 (e.g. reading symbol files or core files). This allows global parameters to
430 be set, which will apply during the symbol reading. The ./.gdbinit is still
431 read after argv processing.
433 * New hosts supported
435 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
437 Linux support i386-unknown-linux or linux
439 We are also including code to support the HP/PA running BSD and HPUX. This
440 is almost guaranteed not to work, as we didn't have time to test or build it
441 for this release. We are including it so that the more adventurous (or
442 masochistic) of you can play with it. We also had major problems with the
443 fact that the compiler that we got from HP doesn't support the -g option.
446 * New targets supported
448 Hitachi H8/300 h8300-hitachi-hms or h8300hms
450 * More smarts about finding #include files
452 GDB now remembers the compilation directory for all include files, and for
453 all files from which C is generated (like yacc and lex sources). This
454 greatly improves GDB's ability to find yacc/lex sources, and include files,
455 especially if you are debugging your program from a directory different from
456 the one that contains your sources.
458 We also fixed a bug which caused difficulty with listing and setting
459 breakpoints in include files which contain C code. (In the past, you had to
460 try twice in order to list an include file that you hadn't looked at before.)
462 * Interesting infernals change
464 GDB now deals with arbitrary numbers of sections, where the symbols for each
465 section must be relocated relative to that section's landing place in the
466 target's address space. This work was needed to support ELF with embedded
467 stabs used by Solaris-2.0.
469 * Bug fixes (of course!)
471 There have been loads of fixes for the following things:
472 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
473 i960, stabs, DOS(GO32), procfs, etc...
475 See the ChangeLog for details.
477 *** Changes in GDB-4.5:
479 * New machines supported (host and target)
481 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
483 SGI Irix-4.x mips-sgi-irix4 or iris4
487 GDB now uses a new memory manager called mmalloc, based on gmalloc.
488 Mmalloc is capable of handling mutiple heaps of memory. It is also
489 capable of saving a heap to a file, and then mapping it back in later.
490 This can be used to greatly speedup the startup of GDB by using a
491 pre-parsed symbol table which lives in a mmalloc managed heap. For
492 more details, please read mmalloc/mmalloc.texi.
496 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
497 'help info proc' for details.
499 * MIPS ecoff symbol table format
501 The code that reads MIPS symbol table format is now supported on all hosts.
502 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
505 * File name changes for MS-DOS
507 Many files in the config directories have been renamed to make it easier to
508 support GDB on MS-DOSe systems (which have very restrictive file name
509 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
510 environment) is close to working but has some remaining problems. Note
511 that debugging of DOS programs is not supported, due to limitations
512 in the ``operating system'', but it can be used to host cross-debugging.
514 * Cross byte order fixes
516 Many fixes have been made to support cross debugging of Sparc and MIPS
517 targets from hosts whose byte order differs.
519 * New -mapped and -readnow options
521 If memory-mapped files are available on your system through the 'mmap'
522 system call, you can use the -mapped option on the `file' or
523 `symbol-file' commands to cause GDB to write the symbols from your
524 program into a reusable file. If the program you are debugging is
525 called `/path/fred', the mapped symbol file will be `./fred.syms'.
526 Future GDB debugging sessions will notice the presence of this file,
527 and will quickly map in symbol information from it, rather than reading
528 the symbol table from the executable program. Using the '-mapped'
529 option in a GDB `file' or `symbol-file' command has the same effect as
530 starting GDB with the '-mapped' command-line option.
532 You can cause GDB to read the entire symbol table immediately by using
533 the '-readnow' option with any of the commands that load symbol table
534 information (or on the GDB command line). This makes the command
535 slower, but makes future operations faster.
537 The -mapped and -readnow options are typically combined in order to
538 build a `fred.syms' file that contains complete symbol information.
539 A simple GDB invocation to do nothing but build a `.syms' file for future
542 gdb -batch -nx -mapped -readnow programname
544 The `.syms' file is specific to the host machine on which GDB is run.
545 It holds an exact image of GDB's internal symbol table. It cannot be
546 shared across multiple host platforms.
550 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
551 siglongjmp() without losing control. This feature has not yet been ported to
552 all systems. It currently works on many 386 platforms, all MIPS-based
553 platforms (SGI, DECstation, etc), and Sun3/4.
557 Preliminary work has been put in to support the new Solaris OS from Sun. At
558 this time, it can control and debug processes, but it is not capable of
563 As always, many many bug fixes. The major areas were with g++, and mipsread.
564 People using the MIPS-based platforms should experience fewer mysterious
565 crashes and trashed symbol tables.
567 *** Changes in GDB-4.4:
569 * New machines supported (host and target)
571 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
573 BSD Reno on Vax vax-dec-bsd
574 Ultrix on Vax vax-dec-ultrix
576 * New machines supported (target)
578 AMD 29000 embedded, using EBMON a29k-none-none
582 GDB continues to improve its handling of C++. `References' work better.
583 The demangler has also been improved, and now deals with symbols mangled as
584 per the Annotated C++ Reference Guide.
586 GDB also now handles `stabs' symbol information embedded in MIPS
587 `ecoff' symbol tables. Since the ecoff format was not easily
588 extensible to handle new languages such as C++, this appeared to be a
589 good way to put C++ debugging info into MIPS binaries. This option
590 will be supported in the GNU C compiler, version 2, when it is
593 * New features for SVR4
595 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
596 shared libraries. Debugging dynamically linked programs should present
597 only minor differences from debugging statically linked programs.
599 The `info proc' command will print out information about any process
600 on an SVR4 system (including the one you are debugging). At the moment,
601 it prints the address mappings of the process.
603 If you bring up GDB on another SVR4 system, please send mail to
604 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
606 * Better dynamic linking support in SunOS
608 Reading symbols from shared libraries which contain debugging symbols
609 now works properly. However, there remain issues such as automatic
610 skipping of `transfer vector' code during function calls, which
611 make it harder to debug code in a shared library, than to debug the
612 same code linked statically.
616 GDB is now using the latest `getopt' routines from the FSF. This
617 version accepts the -- prefix for options with long names. GDB will
618 continue to accept the old forms (-option and +option) as well.
619 Various single letter abbreviations for options have been explicity
620 added to the option table so that they won't get overshadowed in the
621 future by other options that begin with the same letter.
625 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
626 Many assorted bugs have been handled. Many more remain to be handled.
627 See the various ChangeLog files (primarily in gdb and bfd) for details.
630 *** Changes in GDB-4.3:
632 * New machines supported (host and target)
634 Amiga 3000 running Amix m68k-cbm-svr4 or amix
635 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
636 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
638 * Almost SCO Unix support
640 We had hoped to support:
641 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
642 (except for core file support), but we discovered very late in the release
643 that it has problems with process groups that render gdb unusable. Sorry
644 about that. I encourage people to fix it and post the fixes.
646 * Preliminary ELF and DWARF support
648 GDB can read ELF object files on System V Release 4, and can handle
649 debugging records for C, in DWARF format, in ELF files. This support
650 is preliminary. If you bring up GDB on another SVR4 system, please
651 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
656 GDB now uses the latest `readline' library. One user-visible change
657 is that two tabs will list possible command completions, which previously
658 required typing M-? (meta-question mark, or ESC ?).
662 The `stepi' bug that many of you noticed has been squashed.
663 Many bugs in C++ have been handled. Many more remain to be handled.
664 See the various ChangeLog files (primarily in gdb and bfd) for details.
666 * State of the MIPS world (in case you wondered):
668 GDB can understand the symbol tables emitted by the compilers
669 supplied by most vendors of MIPS-based machines, including DEC. These
670 symbol tables are in a format that essentially nobody else uses.
672 Some versions of gcc come with an assembler post-processor called
673 mips-tfile. This program is required if you want to do source-level
674 debugging of gcc-compiled programs. I believe FSF does not ship
675 mips-tfile with gcc version 1, but it will eventually come with gcc
678 Debugging of g++ output remains a problem. g++ version 1.xx does not
679 really support it at all. (If you're lucky, you should be able to get
680 line numbers and stack traces to work, but no parameters or local
681 variables.) With some work it should be possible to improve the
684 When gcc version 2 is released, you will have somewhat better luck.
685 However, even then you will get confusing results for inheritance and
688 We will eventually provide full debugging of g++ output on
689 DECstations. This will probably involve some kind of stabs-in-ecoff
690 encapulation, but the details have not been worked out yet.
693 *** Changes in GDB-4.2:
695 * Improved configuration
697 Only one copy of `configure' exists now, and it is not self-modifying.
698 Porting BFD is simpler.
702 The `step' and `next' commands now only stop at the first instruction
703 of a source line. This prevents the multiple stops that used to occur
704 in switch statements, for-loops, etc. `Step' continues to stop if a
705 function that has debugging information is called within the line.
709 Lots of small bugs fixed. More remain.
711 * New host supported (not target)
713 Intel 386 PC clone running Mach i386-none-mach
716 *** Changes in GDB-4.1:
718 * Multiple source language support
720 GDB now has internal scaffolding to handle several source languages.
721 It determines the type of each source file from its filename extension,
722 and will switch expression parsing and number formatting to match the
723 language of the function in the currently selected stack frame.
724 You can also specifically set the language to be used, with
725 `set language c' or `set language modula-2'.
729 GDB now has preliminary support for the GNU Modula-2 compiler,
730 currently under development at the State University of New York at
731 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
732 continue through the fall of 1991 and into 1992.
734 Other Modula-2 compilers are currently not supported, and attempting to
735 debug programs compiled with them will likely result in an error as the
736 symbol table is read. Feel free to work on it, though!
738 There are hooks in GDB for strict type checking and range checking,
739 in the `Modula-2 philosophy', but they do not currently work.
743 GDB can now write to executable and core files (e.g. patch
744 a variable's value). You must turn this switch on, specify
745 the file ("exec foo" or "core foo"), *then* modify it, e.g.
746 by assigning a new value to a variable. Modifications take
749 * Automatic SunOS shared library reading
751 When you run your program, GDB automatically determines where its
752 shared libraries (if any) have been loaded, and reads their symbols.
753 The `share' command is no longer needed. This also works when
754 examining core files.
758 You can specify the number of lines that the `list' command shows.
761 * New machines supported (host and target)
763 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
764 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
765 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
767 * New hosts supported (not targets)
769 IBM RT/PC: romp-ibm-aix or rtpc
771 * New targets supported (not hosts)
773 AMD 29000 embedded with COFF a29k-none-coff
774 AMD 29000 embedded with a.out a29k-none-aout
775 Ultracomputer remote kernel debug a29k-nyu-kern
777 * New remote interfaces
783 *** Changes in GDB-4.0:
787 Wide output is wrapped at good places to make the output more readable.
789 Gdb now supports cross-debugging from a host machine of one type to a
790 target machine of another type. Communication with the target system
791 is over serial lines. The ``target'' command handles connecting to the
792 remote system; the ``load'' command will download a program into the
793 remote system. Serial stubs for the m68k and i386 are provided. Gdb
794 also supports debugging of realtime processes running under VxWorks,
795 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
796 stub on the target system.
798 New CPUs supported include the AMD 29000 and Intel 960.
800 GDB now reads object files and symbol tables via a ``binary file''
801 library, which allows a single copy of GDB to debug programs of multiple
802 object file types such as a.out and coff.
804 There is now a GDB reference card in "doc/refcard.tex". (Make targets
805 refcard.dvi and refcard.ps are available to format it).
808 * Control-Variable user interface simplified
810 All variables that control the operation of the debugger can be set
811 by the ``set'' command, and displayed by the ``show'' command.
813 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
814 ``Show prompt'' produces the response:
815 Gdb's prompt is new-gdb=>.
817 What follows are the NEW set commands. The command ``help set'' will
818 print a complete list of old and new set commands. ``help set FOO''
819 will give a longer description of the variable FOO. ``show'' will show
820 all of the variable descriptions and their current settings.
822 confirm on/off: Enables warning questions for operations that are
823 hard to recover from, e.g. rerunning the program while
824 it is already running. Default is ON.
826 editing on/off: Enables EMACS style command line editing
827 of input. Previous lines can be recalled with
828 control-P, the current line can be edited with control-B,
829 you can search for commands with control-R, etc.
832 history filename NAME: NAME is where the gdb command history
833 will be stored. The default is .gdb_history,
834 or the value of the environment variable
837 history size N: The size, in commands, of the command history. The
838 default is 256, or the value of the environment variable
841 history save on/off: If this value is set to ON, the history file will
842 be saved after exiting gdb. If set to OFF, the
843 file will not be saved. The default is OFF.
845 history expansion on/off: If this value is set to ON, then csh-like
846 history expansion will be performed on
847 command line input. The default is OFF.
849 radix N: Sets the default radix for input and output. It can be set
850 to 8, 10, or 16. Note that the argument to "radix" is interpreted
851 in the current radix, so "set radix 10" is always a no-op.
853 height N: This integer value is the number of lines on a page. Default
854 is 24, the current `stty rows'' setting, or the ``li#''
855 setting from the termcap entry matching the environment
858 width N: This integer value is the number of characters on a line.
859 Default is 80, the current `stty cols'' setting, or the ``co#''
860 setting from the termcap entry matching the environment
863 Note: ``set screensize'' is obsolete. Use ``set height'' and
864 ``set width'' instead.
866 print address on/off: Print memory addresses in various command displays,
867 such as stack traces and structure values. Gdb looks
868 more ``symbolic'' if you turn this off; it looks more
869 ``machine level'' with it on. Default is ON.
871 print array on/off: Prettyprint arrays. New convenient format! Default
874 print demangle on/off: Print C++ symbols in "source" form if on,
877 print asm-demangle on/off: Same, for assembler level printouts
880 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
883 * Support for Epoch Environment.
885 The epoch environment is a version of Emacs v18 with windowing. One
886 new command, ``inspect'', is identical to ``print'', except that if you
887 are running in the epoch environment, the value is printed in its own
891 * Support for Shared Libraries
893 GDB can now debug programs and core files that use SunOS shared libraries.
894 Symbols from a shared library cannot be referenced
895 before the shared library has been linked with the program (this
896 happens after you type ``run'' and before the function main() is entered).
897 At any time after this linking (including when examining core files
898 from dynamically linked programs), gdb reads the symbols from each
899 shared library when you type the ``sharedlibrary'' command.
900 It can be abbreviated ``share''.
902 sharedlibrary REGEXP: Load shared object library symbols for files
903 matching a unix regular expression. No argument
904 indicates to load symbols for all shared libraries.
906 info sharedlibrary: Status of loaded shared libraries.
911 A watchpoint stops execution of a program whenever the value of an
912 expression changes. Checking for this slows down execution
913 tremendously whenever you are in the scope of the expression, but is
914 quite useful for catching tough ``bit-spreader'' or pointer misuse
915 problems. Some machines such as the 386 have hardware for doing this
916 more quickly, and future versions of gdb will use this hardware.
918 watch EXP: Set a watchpoint (breakpoint) for an expression.
920 info watchpoints: Information about your watchpoints.
922 delete N: Deletes watchpoint number N (same as breakpoints).
923 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
924 enable N: Re-enables watchpoint number N (same as breakpoints).
927 * C++ multiple inheritance
929 When used with a GCC version 2 compiler, GDB supports multiple inheritance
932 * C++ exception handling
934 Gdb now supports limited C++ exception handling. Besides the existing
935 ability to breakpoint on an exception handler, gdb can breakpoint on
936 the raising of an exception (before the stack is peeled back to the
939 catch FOO: If there is a FOO exception handler in the dynamic scope,
940 set a breakpoint to catch exceptions which may be raised there.
941 Multiple exceptions (``catch foo bar baz'') may be caught.
943 info catch: Lists all exceptions which may be caught in the
947 * Minor command changes
949 The command ``call func (arg, arg, ...)'' now acts like the print
950 command, except it does not print or save a value if the function's result
951 is void. This is similar to dbx usage.
953 The ``up'' and ``down'' commands now always print the frame they end up
954 at; ``up-silently'' and `down-silently'' can be used in scripts to change
955 frames without printing.
957 * New directory command
959 'dir' now adds directories to the FRONT of the source search path.
960 The path starts off empty. Source files that contain debug information
961 about the directory in which they were compiled can be found even
962 with an empty path; Sun CC and GCC include this information. If GDB can't
963 find your source file in the current directory, type "dir .".
965 * Configuring GDB for compilation
967 For normal use, type ``./configure host''. See README or gdb.texinfo
970 GDB now handles cross debugging. If you are remotely debugging between
971 two different machines, type ``./configure host -target=targ''.
972 Host is the machine where GDB will run; targ is the machine
973 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob