1 What has changed since GDB-3.5?
2 (Organized release by release)
4 *** Changes in GDB-???:
6 * User visible changes:
8 All vxworks based targets now support a user settable option, called
9 vxworks-timeout. This option represents the number of seconds gdb
10 should wait for responses to rpc's. You might want to use this if
11 your vxworks target is, perhaps, a slow software simulator or happens
12 to be on the far side of a thin network line.
14 *** Changes in GDB-4.9:
18 This is the first GDB release which is accompanied by a matching testsuite.
19 The testsuite requires installation of dejagnu, which should be available
20 via ftp from most sites that carry GNU software.
24 'Cfront' style demangling has had its name changed to 'ARM' style, to
25 emphasize that it was written from the specifications in the C++ Annotated
26 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
27 disclaimers, it still generated too much confusion with users attempting to
28 use gdb with AT&T cfront.
32 GDB now uses a standard remote interface to a simulator library.
33 So far, the library contains simulators for the Zilog Z8001/2, the
34 Hitachi H8/300, H8/500 and Super-H.
36 * New targets supported
38 H8/300 simulator h8300-hitachi-hms or h8300hms
39 H8/500 simulator h8500-hitachi-hms or h8500hms
40 SH simulator sh-hitachi-hms or sh
41 Z8000 simulator z8k-zilog-none or z8ksim
42 IDT MIPS board over serial line mips-idt-ecoff
44 Cross-debugging to GO32 targets is supported. It requires a custom
45 version of the i386-stub.c module which is integrated with the
48 * New remote protocols
50 MIPS remote debugging protocol.
52 * New source languages supported
54 This version includes preliminary support for Chill, a Pascal like language
55 used by telecommunications companies. Chill support is also being integrated
56 into the GNU compiler, but we don't know when it will be publically available.
59 *** Changes in GDB-4.8:
61 * HP Precision Architecture supported
63 GDB now supports HP PA-RISC machines running HPUX. A preliminary
64 version of this support was available as a set of patches from the
65 University of Utah. GDB does not support debugging of programs
66 compiled with the HP compiler, because HP will not document their file
67 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
68 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
70 Many problems in the preliminary version have been fixed.
72 * Faster and better demangling
74 We have improved template demangling and fixed numerous bugs in the GNU style
75 demangler. It can now handle type modifiers such as `static' or `const'. Wide
76 character types (wchar_t) are now supported. Demangling of each symbol is now
77 only done once, and is cached when the symbol table for a file is read in.
78 This results in a small increase in memory usage for C programs, a moderate
79 increase in memory usage for C++ programs, and a fantastic speedup in
82 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
83 from the specifications in the Annotated Reference Manual, which AT&T's
84 compiler does not actually implement.
86 * G++ multiple inheritance compiler problem
88 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
89 inheritance lattices was reworked to properly discover ambiguities. We
90 recently found an example which causes this new algorithm to fail in a
91 very subtle way, producing bad debug information for those classes.
92 The file 'gcc.patch' (in this directory) can be applied to gcc to
93 circumvent the problem. A future GCC release will contain a complete
96 The previous G++ debug info problem (mentioned below for the gdb-4.7
97 release) is fixed in gcc version 2.3.2.
99 * Improved configure script
101 The `configure' script will now attempt to guess your system type if
102 you don't supply a host system type. The old scheme of supplying a
103 host system triplet is preferable over using this. All the magic is
104 done in the new `config.guess' script. Examine it for details.
106 We have also brought our configure script much more in line with the FSF's
107 version. It now supports the --with-xxx options. In particular,
108 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
109 The resulting GDB will not be able to read arbitrary object file formats --
110 only the format ``expected'' to be used on the configured target system.
111 We hope to make this the default in a future release.
113 * Documentation improvements
115 There's new internal documentation on how to modify GDB, and how to
116 produce clean changes to the code. We implore people to read it
117 before submitting changes.
119 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
120 M4 macros. The new texinfo.tex is provided in this release. Pre-built
121 `info' files are also provided. To build `info' files from scratch,
122 you will need the latest `makeinfo' release, which will be available in
123 a future texinfo-X.Y release.
125 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
126 We're not sure exactly which versions have this problem, but it has
127 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
128 or better. If that isn't possible, there is a patch in
129 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
134 GDB now supports array constants that can be used in expressions typed in by
135 the user. The syntax is `{element, element, ...}'. Ie: you can now type
136 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
139 The new directory `gdb/sparclite' contains a program that demonstrates
140 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
142 * New native hosts supported
144 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
145 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
147 * New targets supported
149 AMD 29k family via UDI a29k-amd-udi or udi29k
151 * New file formats supported
153 BFD now supports reading HP/PA-RISC executables (SOM file format?),
154 HPUX core files, and SCO 3.2v2 core files.
158 Attaching to processes now works again; thanks for the many bug reports.
160 We have also stomped on a bunch of core dumps caused by
161 printf_filtered("%s") problems.
163 We eliminated a copyright problem on the rpc and ptrace header files
164 for VxWorks, which was discovered at the last minute during the 4.7
165 release. You should now be able to build a VxWorks GDB.
167 You can now interrupt gdb while an attached process is running. This
168 will cause the attached process to stop, and give control back to GDB.
170 We fixed problems caused by using too many file descriptors
171 for reading symbols from object files and libraries. This was
172 especially a problem for programs that used many (~100) shared
175 The `step' command now only enters a subroutine if there is line number
176 information for the subroutine. Otherwise it acts like the `next'
177 command. Previously, `step' would enter subroutines if there was
178 any debugging information about the routine. This avoids problems
179 when using `cc -g1' on MIPS machines.
181 * Internal improvements
183 GDB's internal interfaces have been improved to make it easier to support
184 debugging of multiple languages in the future.
186 GDB now uses a common structure for symbol information internally.
187 Minimal symbols (derived from linkage symbols in object files), partial
188 symbols (from a quick scan of debug information), and full symbols
189 contain a common subset of information, making it easier to write
190 shared code that handles any of them.
192 * New command line options
194 We now accept --silent as an alias for --quiet.
198 The memory-mapped-malloc library is now licensed under the GNU Library
199 General Public License.
201 *** Changes in GDB-4.7:
203 * Host/native/target split
205 GDB has had some major internal surgery to untangle the support for
206 hosts and remote targets. Now, when you configure GDB for a remote
207 target, it will no longer load in all of the support for debugging
208 local programs on the host. When fully completed and tested, this will
209 ensure that arbitrary host/target combinations are possible.
211 The primary conceptual shift is to separate the non-portable code in
212 GDB into three categories. Host specific code is required any time GDB
213 is compiled on that host, regardless of the target. Target specific
214 code relates to the peculiarities of the target, but can be compiled on
215 any host. Native specific code is everything else: it can only be
216 built when the host and target are the same system. Child process
217 handling and core file support are two common `native' examples.
219 GDB's use of /proc for controlling Unix child processes is now cleaner.
220 It has been split out into a single module under the `target_ops' vector,
221 plus two native-dependent functions for each system that uses /proc.
223 * New hosts supported
225 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
226 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
227 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
229 * New targets supported
231 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
232 68030 and CPU32 m68030-*-*, m68332-*-*
234 * New native hosts supported
236 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
237 (386bsd is not well tested yet)
238 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
240 * New file formats supported
242 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
243 supports reading of `a.out.adobe' object files, which are an a.out
244 format extended with minimal information about multiple sections.
248 `show copying' is the same as the old `info copying'.
249 `show warranty' is the same as `info warrantee'.
250 These were renamed for consistency. The old commands continue to work.
252 `info handle' is a new alias for `info signals'.
254 You can now define pre-command hooks, which attach arbitrary command
255 scripts to any command. The commands in the hook will be executed
256 prior to the user's command. You can also create a hook which will be
257 executed whenever the program stops. See gdb.texinfo.
261 We now deal with Cfront style name mangling, and can even extract type
262 info from mangled symbols. GDB can automatically figure out which
263 symbol mangling style your C++ compiler uses.
265 Calling of methods and virtual functions has been improved as well.
269 The crash that occured when debugging Sun Ansi-C compiled binaries is
270 fixed. This was due to mishandling of the extra N_SO stabs output
273 We also finally got Ultrix 4.2 running in house, and fixed core file
274 support, with help from a dozen people on the net.
276 John M. Farrell discovered that the reason that single-stepping was so
277 slow on all of the Mips based platforms (primarily SGI and DEC) was
278 that we were trying to demangle and lookup a symbol used for internal
279 purposes on every instruction that was being stepped through. Changing
280 the name of that symbol so that it couldn't be mistaken for a C++
281 mangled symbol sped things up a great deal.
283 Rich Pixley sped up symbol lookups in general by getting much smarter
284 about when C++ symbol mangling is necessary. This should make symbol
285 completion (TAB on the command line) much faster. It's not as fast as
286 we'd like, but it's significantly faster than gdb-4.6.
290 A new user controllable variable 'call_scratch_address' can
291 specify the location of a scratch area to be used when GDB
292 calls a function in the target. This is necessary because the
293 usual method of putting the scratch area on the stack does not work
294 in systems that have separate instruction and data spaces.
296 We integrated changes to support the 29k UDI (Universal Debugger
297 Interface), but discovered at the last minute that we didn't have all
298 of the appropriate copyright paperwork. We are working with AMD to
299 resolve this, and hope to have it available soon.
303 We have sped up the remote serial line protocol, especially for targets
304 with lots of registers. It now supports a new `expedited status' ('T')
305 message which can be used in place of the existing 'S' status message.
306 This allows the remote stub to send only the registers that GDB
307 needs to make a quick decision about single-stepping or conditional
308 breakpoints, eliminating the need to fetch the entire register set for
309 each instruction being stepped through.
311 The GDB remote serial protocol now implements a write-through cache for
312 registers, only re-reading the registers if the target has run.
314 There is also a new remote serial stub for SPARC processors. You can
315 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
316 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
317 processor with a serial port.
321 Configure.in files have become much easier to read and modify. A new
322 `table driven' format makes it more obvious what configurations are
323 supported, and what files each one uses.
327 There is a new opcodes library which will eventually contain all of the
328 disassembly routines and opcode tables. At present, it only contains
329 Sparc and Z8000 routines. This will allow the assembler, debugger, and
330 disassembler (binutils/objdump) to share these routines.
332 The libiberty library is now copylefted under the GNU Library General
333 Public License. This allows more liberal use, and was done so libg++
334 can use it. This makes no difference to GDB, since the Library License
335 grants all the rights from the General Public License.
339 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
340 reference to the stabs symbol info used by the debugger. It is (as far
341 as we know) the only published document on this fascinating topic. We
342 encourage you to read it, compare it to the stabs information on your
343 system, and send improvements on the document in general (to
344 bug-gdb@prep.ai.mit.edu).
346 And, of course, many bugs have been fixed.
349 *** Changes in GDB-4.6:
351 * Better support for C++ function names
353 GDB now accepts as input the "demangled form" of C++ overloaded function
354 names and member function names, and can do command completion on such names
355 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
356 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
357 Make use of command completion, it is your friend.
359 GDB also now accepts a variety of C++ mangled symbol formats. They are
360 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
361 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
362 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
363 for the list of formats.
365 * G++ symbol mangling problem
367 Recent versions of gcc have a bug in how they emit debugging information for
368 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
369 directory) can be applied to gcc to fix the problem. Alternatively, if you
370 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
371 usual symptom is difficulty with setting breakpoints on methods. GDB complains
372 about the method being non-existent. (We believe that version 2.2.2 of GCC has
375 * New 'maintenance' command
377 All of the commands related to hacking GDB internals have been moved out of
378 the main command set, and now live behind the 'maintenance' command. This
379 can also be abbreviated as 'mt'. The following changes were made:
381 dump-me -> maintenance dump-me
382 info all-breakpoints -> maintenance info breakpoints
383 printmsyms -> maintenance print msyms
384 printobjfiles -> maintenance print objfiles
385 printpsyms -> maintenance print psymbols
386 printsyms -> maintenance print symbols
388 The following commands are new:
390 maintenance demangle Call internal GDB demangler routine to
391 demangle a C++ link name and prints the result.
392 maintenance print type Print a type chain for a given symbol
394 * Change to .gdbinit file processing
396 We now read the $HOME/.gdbinit file before processing the argv arguments
397 (e.g. reading symbol files or core files). This allows global parameters to
398 be set, which will apply during the symbol reading. The ./.gdbinit is still
399 read after argv processing.
401 * New hosts supported
403 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
405 Linux support i386-unknown-linux or linux
407 We are also including code to support the HP/PA running BSD and HPUX. This
408 is almost guaranteed not to work, as we didn't have time to test or build it
409 for this release. We are including it so that the more adventurous (or
410 masochistic) of you can play with it. We also had major problems with the
411 fact that the compiler that we got from HP doesn't support the -g option.
414 * New targets supported
416 Hitachi H8/300 h8300-hitachi-hms or h8300hms
418 * More smarts about finding #include files
420 GDB now remembers the compilation directory for all include files, and for
421 all files from which C is generated (like yacc and lex sources). This
422 greatly improves GDB's ability to find yacc/lex sources, and include files,
423 especially if you are debugging your program from a directory different from
424 the one that contains your sources.
426 We also fixed a bug which caused difficulty with listing and setting
427 breakpoints in include files which contain C code. (In the past, you had to
428 try twice in order to list an include file that you hadn't looked at before.)
430 * Interesting infernals change
432 GDB now deals with arbitrary numbers of sections, where the symbols for each
433 section must be relocated relative to that section's landing place in the
434 target's address space. This work was needed to support ELF with embedded
435 stabs used by Solaris-2.0.
437 * Bug fixes (of course!)
439 There have been loads of fixes for the following things:
440 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
441 i960, stabs, DOS(GO32), procfs, etc...
443 See the ChangeLog for details.
445 *** Changes in GDB-4.5:
447 * New machines supported (host and target)
449 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
451 SGI Irix-4.x mips-sgi-irix4 or iris4
455 GDB now uses a new memory manager called mmalloc, based on gmalloc.
456 Mmalloc is capable of handling mutiple heaps of memory. It is also
457 capable of saving a heap to a file, and then mapping it back in later.
458 This can be used to greatly speedup the startup of GDB by using a
459 pre-parsed symbol table which lives in a mmalloc managed heap. For
460 more details, please read mmalloc/mmalloc.texi.
464 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
465 'help info proc' for details.
467 * MIPS ecoff symbol table format
469 The code that reads MIPS symbol table format is now supported on all hosts.
470 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
473 * File name changes for MS-DOS
475 Many files in the config directories have been renamed to make it easier to
476 support GDB on MS-DOSe systems (which have very restrictive file name
477 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
478 environment) is close to working but has some remaining problems. Note
479 that debugging of DOS programs is not supported, due to limitations
480 in the ``operating system'', but it can be used to host cross-debugging.
482 * Cross byte order fixes
484 Many fixes have been made to support cross debugging of Sparc and MIPS
485 targets from hosts whose byte order differs.
487 * New -mapped and -readnow options
489 If memory-mapped files are available on your system through the 'mmap'
490 system call, you can use the -mapped option on the `file' or
491 `symbol-file' commands to cause GDB to write the symbols from your
492 program into a reusable file. If the program you are debugging is
493 called `/path/fred', the mapped symbol file will be `./fred.syms'.
494 Future GDB debugging sessions will notice the presence of this file,
495 and will quickly map in symbol information from it, rather than reading
496 the symbol table from the executable program. Using the '-mapped'
497 option in a GDB `file' or `symbol-file' command has the same effect as
498 starting GDB with the '-mapped' command-line option.
500 You can cause GDB to read the entire symbol table immediately by using
501 the '-readnow' option with any of the commands that load symbol table
502 information (or on the GDB command line). This makes the command
503 slower, but makes future operations faster.
505 The -mapped and -readnow options are typically combined in order to
506 build a `fred.syms' file that contains complete symbol information.
507 A simple GDB invocation to do nothing but build a `.syms' file for future
510 gdb -batch -nx -mapped -readnow programname
512 The `.syms' file is specific to the host machine on which GDB is run.
513 It holds an exact image of GDB's internal symbol table. It cannot be
514 shared across multiple host platforms.
518 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
519 siglongjmp() without losing control. This feature has not yet been ported to
520 all systems. It currently works on many 386 platforms, all MIPS-based
521 platforms (SGI, DECstation, etc), and Sun3/4.
525 Preliminary work has been put in to support the new Solaris OS from Sun. At
526 this time, it can control and debug processes, but it is not capable of
531 As always, many many bug fixes. The major areas were with g++, and mipsread.
532 People using the MIPS-based platforms should experience fewer mysterious
533 crashes and trashed symbol tables.
535 *** Changes in GDB-4.4:
537 * New machines supported (host and target)
539 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
541 BSD Reno on Vax vax-dec-bsd
542 Ultrix on Vax vax-dec-ultrix
544 * New machines supported (target)
546 AMD 29000 embedded, using EBMON a29k-none-none
550 GDB continues to improve its handling of C++. `References' work better.
551 The demangler has also been improved, and now deals with symbols mangled as
552 per the Annotated C++ Reference Guide.
554 GDB also now handles `stabs' symbol information embedded in MIPS
555 `ecoff' symbol tables. Since the ecoff format was not easily
556 extensible to handle new languages such as C++, this appeared to be a
557 good way to put C++ debugging info into MIPS binaries. This option
558 will be supported in the GNU C compiler, version 2, when it is
561 * New features for SVR4
563 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
564 shared libraries. Debugging dynamically linked programs should present
565 only minor differences from debugging statically linked programs.
567 The `info proc' command will print out information about any process
568 on an SVR4 system (including the one you are debugging). At the moment,
569 it prints the address mappings of the process.
571 If you bring up GDB on another SVR4 system, please send mail to
572 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
574 * Better dynamic linking support in SunOS
576 Reading symbols from shared libraries which contain debugging symbols
577 now works properly. However, there remain issues such as automatic
578 skipping of `transfer vector' code during function calls, which
579 make it harder to debug code in a shared library, than to debug the
580 same code linked statically.
584 GDB is now using the latest `getopt' routines from the FSF. This
585 version accepts the -- prefix for options with long names. GDB will
586 continue to accept the old forms (-option and +option) as well.
587 Various single letter abbreviations for options have been explicity
588 added to the option table so that they won't get overshadowed in the
589 future by other options that begin with the same letter.
593 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
594 Many assorted bugs have been handled. Many more remain to be handled.
595 See the various ChangeLog files (primarily in gdb and bfd) for details.
598 *** Changes in GDB-4.3:
600 * New machines supported (host and target)
602 Amiga 3000 running Amix m68k-cbm-svr4 or amix
603 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
604 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
606 * Almost SCO Unix support
608 We had hoped to support:
609 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
610 (except for core file support), but we discovered very late in the release
611 that it has problems with process groups that render gdb unusable. Sorry
612 about that. I encourage people to fix it and post the fixes.
614 * Preliminary ELF and DWARF support
616 GDB can read ELF object files on System V Release 4, and can handle
617 debugging records for C, in DWARF format, in ELF files. This support
618 is preliminary. If you bring up GDB on another SVR4 system, please
619 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
624 GDB now uses the latest `readline' library. One user-visible change
625 is that two tabs will list possible command completions, which previously
626 required typing M-? (meta-question mark, or ESC ?).
630 The `stepi' bug that many of you noticed has been squashed.
631 Many bugs in C++ have been handled. Many more remain to be handled.
632 See the various ChangeLog files (primarily in gdb and bfd) for details.
634 * State of the MIPS world (in case you wondered):
636 GDB can understand the symbol tables emitted by the compilers
637 supplied by most vendors of MIPS-based machines, including DEC. These
638 symbol tables are in a format that essentially nobody else uses.
640 Some versions of gcc come with an assembler post-processor called
641 mips-tfile. This program is required if you want to do source-level
642 debugging of gcc-compiled programs. I believe FSF does not ship
643 mips-tfile with gcc version 1, but it will eventually come with gcc
646 Debugging of g++ output remains a problem. g++ version 1.xx does not
647 really support it at all. (If you're lucky, you should be able to get
648 line numbers and stack traces to work, but no parameters or local
649 variables.) With some work it should be possible to improve the
652 When gcc version 2 is released, you will have somewhat better luck.
653 However, even then you will get confusing results for inheritance and
656 We will eventually provide full debugging of g++ output on
657 DECstations. This will probably involve some kind of stabs-in-ecoff
658 encapulation, but the details have not been worked out yet.
661 *** Changes in GDB-4.2:
663 * Improved configuration
665 Only one copy of `configure' exists now, and it is not self-modifying.
666 Porting BFD is simpler.
670 The `step' and `next' commands now only stop at the first instruction
671 of a source line. This prevents the multiple stops that used to occur
672 in switch statements, for-loops, etc. `Step' continues to stop if a
673 function that has debugging information is called within the line.
677 Lots of small bugs fixed. More remain.
679 * New host supported (not target)
681 Intel 386 PC clone running Mach i386-none-mach
684 *** Changes in GDB-4.1:
686 * Multiple source language support
688 GDB now has internal scaffolding to handle several source languages.
689 It determines the type of each source file from its filename extension,
690 and will switch expression parsing and number formatting to match the
691 language of the function in the currently selected stack frame.
692 You can also specifically set the language to be used, with
693 `set language c' or `set language modula-2'.
697 GDB now has preliminary support for the GNU Modula-2 compiler,
698 currently under development at the State University of New York at
699 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
700 continue through the fall of 1991 and into 1992.
702 Other Modula-2 compilers are currently not supported, and attempting to
703 debug programs compiled with them will likely result in an error as the
704 symbol table is read. Feel free to work on it, though!
706 There are hooks in GDB for strict type checking and range checking,
707 in the `Modula-2 philosophy', but they do not currently work.
711 GDB can now write to executable and core files (e.g. patch
712 a variable's value). You must turn this switch on, specify
713 the file ("exec foo" or "core foo"), *then* modify it, e.g.
714 by assigning a new value to a variable. Modifications take
717 * Automatic SunOS shared library reading
719 When you run your program, GDB automatically determines where its
720 shared libraries (if any) have been loaded, and reads their symbols.
721 The `share' command is no longer needed. This also works when
722 examining core files.
726 You can specify the number of lines that the `list' command shows.
729 * New machines supported (host and target)
731 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
732 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
733 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
735 * New hosts supported (not targets)
737 IBM RT/PC: romp-ibm-aix or rtpc
739 * New targets supported (not hosts)
741 AMD 29000 embedded with COFF a29k-none-coff
742 AMD 29000 embedded with a.out a29k-none-aout
743 Ultracomputer remote kernel debug a29k-nyu-kern
745 * New remote interfaces
751 *** Changes in GDB-4.0:
755 Wide output is wrapped at good places to make the output more readable.
757 Gdb now supports cross-debugging from a host machine of one type to a
758 target machine of another type. Communication with the target system
759 is over serial lines. The ``target'' command handles connecting to the
760 remote system; the ``load'' command will download a program into the
761 remote system. Serial stubs for the m68k and i386 are provided. Gdb
762 also supports debugging of realtime processes running under VxWorks,
763 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
764 stub on the target system.
766 New CPUs supported include the AMD 29000 and Intel 960.
768 GDB now reads object files and symbol tables via a ``binary file''
769 library, which allows a single copy of GDB to debug programs of multiple
770 object file types such as a.out and coff.
772 There is now a GDB reference card in "doc/refcard.tex". (Make targets
773 refcard.dvi and refcard.ps are available to format it).
776 * Control-Variable user interface simplified
778 All variables that control the operation of the debugger can be set
779 by the ``set'' command, and displayed by the ``show'' command.
781 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
782 ``Show prompt'' produces the response:
783 Gdb's prompt is new-gdb=>.
785 What follows are the NEW set commands. The command ``help set'' will
786 print a complete list of old and new set commands. ``help set FOO''
787 will give a longer description of the variable FOO. ``show'' will show
788 all of the variable descriptions and their current settings.
790 confirm on/off: Enables warning questions for operations that are
791 hard to recover from, e.g. rerunning the program while
792 it is already running. Default is ON.
794 editing on/off: Enables EMACS style command line editing
795 of input. Previous lines can be recalled with
796 control-P, the current line can be edited with control-B,
797 you can search for commands with control-R, etc.
800 history filename NAME: NAME is where the gdb command history
801 will be stored. The default is .gdb_history,
802 or the value of the environment variable
805 history size N: The size, in commands, of the command history. The
806 default is 256, or the value of the environment variable
809 history save on/off: If this value is set to ON, the history file will
810 be saved after exiting gdb. If set to OFF, the
811 file will not be saved. The default is OFF.
813 history expansion on/off: If this value is set to ON, then csh-like
814 history expansion will be performed on
815 command line input. The default is OFF.
817 radix N: Sets the default radix for input and output. It can be set
818 to 8, 10, or 16. Note that the argument to "radix" is interpreted
819 in the current radix, so "set radix 10" is always a no-op.
821 height N: This integer value is the number of lines on a page. Default
822 is 24, the current `stty rows'' setting, or the ``li#''
823 setting from the termcap entry matching the environment
826 width N: This integer value is the number of characters on a line.
827 Default is 80, the current `stty cols'' setting, or the ``co#''
828 setting from the termcap entry matching the environment
831 Note: ``set screensize'' is obsolete. Use ``set height'' and
832 ``set width'' instead.
834 print address on/off: Print memory addresses in various command displays,
835 such as stack traces and structure values. Gdb looks
836 more ``symbolic'' if you turn this off; it looks more
837 ``machine level'' with it on. Default is ON.
839 print array on/off: Prettyprint arrays. New convenient format! Default
842 print demangle on/off: Print C++ symbols in "source" form if on,
845 print asm-demangle on/off: Same, for assembler level printouts
848 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
851 * Support for Epoch Environment.
853 The epoch environment is a version of Emacs v18 with windowing. One
854 new command, ``inspect'', is identical to ``print'', except that if you
855 are running in the epoch environment, the value is printed in its own
859 * Support for Shared Libraries
861 GDB can now debug programs and core files that use SunOS shared libraries.
862 Symbols from a shared library cannot be referenced
863 before the shared library has been linked with the program (this
864 happens after you type ``run'' and before the function main() is entered).
865 At any time after this linking (including when examining core files
866 from dynamically linked programs), gdb reads the symbols from each
867 shared library when you type the ``sharedlibrary'' command.
868 It can be abbreviated ``share''.
870 sharedlibrary REGEXP: Load shared object library symbols for files
871 matching a unix regular expression. No argument
872 indicates to load symbols for all shared libraries.
874 info sharedlibrary: Status of loaded shared libraries.
879 A watchpoint stops execution of a program whenever the value of an
880 expression changes. Checking for this slows down execution
881 tremendously whenever you are in the scope of the expression, but is
882 quite useful for catching tough ``bit-spreader'' or pointer misuse
883 problems. Some machines such as the 386 have hardware for doing this
884 more quickly, and future versions of gdb will use this hardware.
886 watch EXP: Set a watchpoint (breakpoint) for an expression.
888 info watchpoints: Information about your watchpoints.
890 delete N: Deletes watchpoint number N (same as breakpoints).
891 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
892 enable N: Re-enables watchpoint number N (same as breakpoints).
895 * C++ multiple inheritance
897 When used with a GCC version 2 compiler, GDB supports multiple inheritance
900 * C++ exception handling
902 Gdb now supports limited C++ exception handling. Besides the existing
903 ability to breakpoint on an exception handler, gdb can breakpoint on
904 the raising of an exception (before the stack is peeled back to the
907 catch FOO: If there is a FOO exception handler in the dynamic scope,
908 set a breakpoint to catch exceptions which may be raised there.
909 Multiple exceptions (``catch foo bar baz'') may be caught.
911 info catch: Lists all exceptions which may be caught in the
915 * Minor command changes
917 The command ``call func (arg, arg, ...)'' now acts like the print
918 command, except it does not print or save a value if the function's result
919 is void. This is similar to dbx usage.
921 The ``up'' and ``down'' commands now always print the frame they end up
922 at; ``up-silently'' and `down-silently'' can be used in scripts to change
923 frames without printing.
925 * New directory command
927 'dir' now adds directories to the FRONT of the source search path.
928 The path starts off empty. Source files that contain debug information
929 about the directory in which they were compiled can be found even
930 with an empty path; Sun CC and GCC include this information. If GDB can't
931 find your source file in the current directory, type "dir .".
933 * Configuring GDB for compilation
935 For normal use, type ``./configure host''. See README or gdb.texinfo
938 GDB now handles cross debugging. If you are remotely debugging between
939 two different machines, type ``./configure host -target=targ''.
940 Host is the machine where GDB will run; targ is the machine
941 where the program that you are debugging will run.
projects / deliverable / binutils-gdb.git / blob